JP4451561B2 - Sewing machine with differential - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sewing machine with a differential device that is preferably used for performing, for example, a sewing operation or an embroidery operation, and more particularly to a sewing machine with a differential device that can improve the quality of a sewing product, an embroidery pattern, or the like.
[0002]
[Prior art]
In general, an embroidery machine as a sewing machine used for performing a sewing operation or an embroidery operation is provided on a base, and has a head portion that moves a sewing needle by rotating a main shaft, and is positioned below the head portion. The frame includes a holding frame such as an embroidery frame that is provided on the base and holds a cloth to be embroidered in a stretched state, a frame moving mechanism that moves the holding frame on the base, and the like.
[0003]
In this type of prior art embroidery machine, on the head portion side of the sewing machine, a balance that feeds and tightens an upper thread that is driven according to the rotation of the main shaft and becomes an embroidery thread, and an upper according to the rotation of the main shaft, There is provided a needle bar which is reciprocated downward to drive the sewing needle.
[0004]
Further, on the base side, there is provided a rotary hook for forming a so-called “seam” by entwining the upper thread and the lower thread in accordance with the movement of the sewing needle. The rotary hook is driven in accordance with the rotation of the main shaft, and rotates twice while the main shaft makes one rotation, an outer hook rotating integrally with the hook shaft, and relatively rotatable within the outer hook. It is generally constituted by an inner hook that is disposed and accommodates a bobbin for a bobbin thread (for example, JP-A-11-226284).
[0005]
Here, the balance provided on the head side of the sewing machine is driven up and down with respect to the rotation angle θ of the main shaft as indicated by a characteristic line St shown in FIG. 28, and the needle bar has a characteristic with respect to the rotation angle θ of the main shaft. Driven along line Sh. The hook shaft of the rotary hook is rotated so that its sword tip moves up and down along the characteristic line Sk, and this hook shaft rotates twice while the main shaft makes one rotation.
[0006]
When the rotation angle θ at which the needle bar reaches the top dead center is defined as the needle top dead center θ0 (for example, θ0 = 0 °), the needle bar has a needle bottom dead center θc (for example, θc = 180) along the characteristic line Sh. ), And then reaches the top dead center again at an angle θi (for example, θi = 360 °).
[0007]
Further, the sewing machine needle moved up and down by the needle bar is driven along the characteristic line Sh in the same manner as the needle bar, and the needle tip moves down through the needle plate at the needle entry point θb (for example, θb = 115 °). After entering the yarn side, the needle tip comes out upward from the needle plate at a needle removal point θe (for example, θe = 250 °).
[0008]
On the other hand, the balance is driven along the characteristic line St. For example, when the rotation angle θ of the main shaft is about 60 °, the balance becomes the top dead center θa, and when the rotation angle θ is about 290 °, the balance becomes the bottom dead center θf. To reach.
[0009]
Further, the hook shaft on the lower thread side rotates so that the sword tip moves up and down along the characteristic line Sk. When the hook point reaches the thread hooking point θd (for example, θd = 200 °), the sword hook hooks the upper thread and the rotary hook is rotated. Then, the upper thread reaches the thread removal point θg (for example, θg = 315 °) where the upper thread ends entangled with the lower thread by the rotary hook, and the upper thread is removed from the rotary hook at the hook removal point θh (for example, θh = 358 °). It will come out completely.
[0010]
[Problems to be solved by the invention]
By the way, in the above-described conventional embroidery machine, the balance on the head side, the needle bar, and the shuttle shaft on the lower thread side are mechanically connected to the main shaft using a cam mechanism, a crank mechanism, a gear mechanism, and the like. Since the structure is driven by the rotation of the main shaft with the characteristics illustrated in FIG. 28, the following unsolved problems occur.
[0011]
That is, the sewing tone of the embroidery machine can be changed according to the operation characteristics from the thread threading point θd of the upper thread by the rotary hook to the hook removal point θh. However, as long as the rotary hook shaft is driven along the characteristic line Sk shown in FIG. 28, the relative operating characteristics of the hook shaft, the needle bar, and the balance cannot be changed, and it is difficult to improve the embroidery quality. There is a problem.
[0012]
In this case, in the embroidery machine according to the prior art, as shown in FIG. 28, before reaching the thread drop point θg and the hook drop point θh, for example, to start pulling the thread with the balance as indicated by the characteristic line St, If the thread tension of about 100 to 150 g is not given, the upper thread will be pulled out excessively, resulting in embroidery without thread tightening, or a lump of thread (spider web) on the back of the cloth. There is.
[0013]
Also, if the upper thread is forcibly pulled up by increasing the thread tension, the thread will be tightened too much, resulting in a hard and dull embroidery, or thread breaks will occur frequently, reducing work efficiency. Therefore, the lifting timing of the balance must be slow and slow, and if the embroidery pattern has a large sewing width or swing width, there is a restriction that the sewing needle cannot be moved at high speed.
[0014]
Thus, if the timing of pulling the upper thread with the balance is delayed and the upper thread is pulled slowly, the occurrence of thread breakage is reduced and the embroidery stitches are also beautiful. However, for this purpose, it is necessary to slow down the movement of the balance by lowering the rotation speed of the main shaft, and there is a problem that the embroidery speed is sacrificed, the workability is lowered, and the production efficiency is deteriorated.
[0015]
Also, when forming a seam with a large swing width, it is necessary to increase the frame movement amount by accelerating the frame movement of the embroidery frame, so that the upper thread is pulled before the hook shaft reaches the thread removal point θg. As a result, there is a problem in that there is no room for slack in the upper thread, thread breakage occurs, or the seam is too tight and the quality of the embroidery deteriorates.
[0016]
On the other hand, when the rotational phase of the shuttle shaft is set to be accelerated as a whole, as indicated by a characteristic line Sk ′ indicated by a two-dot chain line in FIG. 28, the thread dropout point θg ′ can be accelerated. Since the point θd 'also becomes faster, for example, when the rotation speed of the main spindle is increased, the upper thread may not be able to be removed with the sword tip of the rotary hook, making the thread hooking itself impossible and causing skipping (blank stitching) There is a problem that it is easy to do.
[0017]
The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to change the rotation phase of the hook shaft and the like in one cycle of rotation of the main shaft so that the main shaft, the balance, the hook shaft, etc. It is an object to provide a sewing machine with a differential device that can improve the embroidery quality and the like by changing the operation characteristics of the sewing machine so that the seam can be finely finished.
[0018]
[Means for Solving the Problems]
  In order to solve the above-described problems, the invention of claim 1 is directed to a main shaft of a sewing machine, a balance that is driven according to the rotation of the main shaft to feed and tighten the upper thread, and is reciprocated according to the rotation of the main shaft. A needle bar for moving the needle, a hook shaft on the lower thread side driven in accordance with the rotation of the main shaft in order to entangle the upper thread and the lower thread in accordance with the needle movement of the sewing machine needle, the needle bar, the balance and the hook shaft A differential device that rotates at least the shuttle shaft in a phase different from that of the main shaft, the differential device being a casing serving as an outer shell, and an input rotatably provided on the casing and rotated by the main shaft. A shaft, an output shaft rotatably provided on the casing and transmitting rotational output to at least the shuttle shaft, and an output provided between the input shaft and the output shaft for transmitting rotation of the input shaft to the output shaft. The rotational phase of the shaft Changing relative fill force axis constituted by the phase difference generating mechanismThe phase difference generating mechanism is provided between the input shaft and the output shaft, and the intermediate shaft provided in the casing and radially spaced from the input shaft and the output shaft. The first and second helical gears for transmitting the first and second helical gears and differential cam means for relatively moving the first and second helical gears in the axial direction according to the rotation of the input shaft, , The second helical gear is provided between at least any two of the input shaft, the intermediate shaft, and the output shaft, and the differential cam means includes a cam wheel that rotates according to the input shaft, A cam follower provided on the casing side so as to be engaged with the cam wheel and displacing the first or second helical gear in the axial direction according to the rotation of the cam wheel.ing.
[0020]
According to a second aspect of the present invention, the differential device changes the rotational phase of the hook shaft from the position where the needle bar is at the bottom dead center, so that the upper thread is rotated by the rotary hook along with the rotation of the hook shaft. And the lower thread are entangled to change the timing at which the upper thread is removed from the rotary hook.
[0022]
  The invention of claim 3Is,A main shaft of the sewing machine, a balance that is driven according to the rotation of the main shaft and feeds and tightens the upper thread, a needle bar that is reciprocated according to the rotation of the main shaft, and moves the sewing needle. A difference in which at least one of the needle bar, the balance and the hook shaft rotates at a phase different from that of the main shaft, and the lower shaft on the lower thread side driven according to the rotation of the main shaft to entangle the yarn and the lower thread. The differential device includes a casing as an outer shell, an input shaft that is rotatably provided on the casing and rotated by the main shaft, and a rotary shaft that is rotatably provided on the casing. An output shaft for transmitting a rotational output, and a phase difference generation provided between the input shaft and the output shaft for transmitting the rotation of the input shaft to the output shaft, and changing the rotational phase of the output shaft with respect to the input shaft With mechanism Configured, theThe phase difference generation mechanism isAn intermediate shaft provided in the casing spaced radially from the input shaft and the output shaft;First and second helical gears provided between an input shaft and an output shaft and meshing with each other to transmit a rotational force, and the first and second helical gears according to the rotation of the input shaft. Differential cam means for relative movement in the direction.The first and second helical gears are provided between at least two of the input shaft, the intermediate shaft and the output shaft, and the differential cam means includes the first helical gear. A first cam wheel that rotates integrally with the gear, a second cam wheel that rotates integrally with the second helical gear, and a first cam wheel provided on the casing side, between the first and second cam wheels. The rotating body is configured to be rotatable about a fulcrum that is positioned, and first and second cam followers that are respectively provided on the rotating body and engage with the first and second cam wheels.ing.
[0030]
  Claims4According to the invention, the first and second cam followers are attached to the rotating body so as to be adjustable in position, and the rotating body is spaced from the first and second cam followers and the fulcrum.(L1, L2)Is variably adjusted.
[0032]
  Claims5According to the invention, the first and second cam wheels have cam grooves of different shapes, and the first and second cam followers are engaged with the cam grooves of the first and second cam wheels. Have.
[0033]
  Meanwhile, claims6According to the invention, a plurality of output shafts are provided in the casing, and a phase difference generating mechanism is provided between each output shaft and the input shaft..
[0034]
  Claims7According to the invention, the plurality of output shafts are configured to transmit rotational outputs having different phases to the balance and the shuttle shaft, respectively..
[0035]
  And claims8According to the invention, between the main shaft motor that drives the main shaft and the drive unit of the needle bar, another differential device that drives the drive unit of the needle bar at a rotational phase different from that of the main shaft motor is provided. Have.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a case where the sewing machine with a differential according to an embodiment of the present invention is applied to a multicolor embroidery machine having a plurality of (for example, 15) sewing needles will be described as an example and described in detail with reference to the accompanying drawings. .
[0037]
Here, FIG. 1 to FIG. 10 show a first embodiment of the present invention. In the figure, reference numeral 1 denotes an embroidery machine. The embroidery machine 1 includes a base 2, left and right side frames 3 and 4 erected on the base 2, and upper sides of the side frames 3 and 4. The head support 5 fixed to the head support 5 and moved to the left and right (in the directions of arrows a and b in FIG. 1) with respect to the head support 5 provided on the front side of the head support 5 The head portion 6 that has become possible, a spindle motor (not shown) that rotationally drives the spindle 7 of the sewing machine, and the like are configured.
[0038]
Further, the embroidery machine 1 is provided with a cheese case (none of which is shown) which is located on the rear side of the head support 5 and accommodates a total of 15 colors of embroidery threads (upper threads) together with respective upper thread bobbins. The embroidery machine 1 constitutes a multicolor embroidery machine that performs embroidery work using these embroidery threads.
[0039]
In addition, the head portion 6 of the embroidery machine 1 is provided with a total of 15 thread hooks 8, 8,... On the upper end side, and a total of 15 thread hooks 8 and a balance 10 described later. Are provided. The upper thread as an embroidery thread drawn from each cheese case is guided to each thread tension 9 via a thread hook 8, and the upper thread is directed toward the balance 10 by the thread tension 9 so as to reduce friction. The yarn is to be fed.
[0040]
The thread tension 9 applies a tension of, for example, about 20 to 50 g, preferably about 30 to 40 g to the upper thread, and when the upper thread is pulled beyond this tension by a sewing needle 12 described later, The upper thread is allowed to be fed toward the head.
[0041]
10, 10,... Represent, for example, a total of 15 balances arranged on the front surface side of the head unit 6, and each of the balances 10 is driven by a balance driving unit (not shown) provided in the head unit 6. 7 is driven up and down as indicated by the characteristic line St in FIG. When the balance 10 is driven downward, it gives a slight slack to the upper thread with the sewing needle 12 and feeds the upper thread to the sewing needle 12 side.
[0042]
Further, when the balance 10 is driven upward, the upper thread is pulled up between a stitch (not shown) formed on an embroidery cloth 13 described later by the sewing needle 12 and the thread tension 9 or the like. Thus, tension is applied to the upper thread, and the seam is tightened and the upper thread is fed out.
[0043]
.. Are, for example, 15 needle bars provided on the lower end side of the head portion 6, and a sewing needle 12 is detachably attached to the lower end side of each needle bar 11. The needle bar 11 and the sewing needle 12 are driven up and down as indicated by a characteristic line Sh in FIG. 9 according to the rotation of the main shaft 7 by a needle drive unit (not shown) provided in the head unit 6. Is.
[0044]
Here, an embroidery cloth 13 as an embroidery object is disposed between the sewing needle 12 on the head portion 6 side and a hook holder 24 described later, as shown by a two-dot chain line in FIG. Is held in a stretched state using a holding frame (not shown) such as an embroidery frame. The embroidery cloth 13 is moved together with the holding frame to the front, rear, left, and right in the horizontal direction. At this time, the sewing needle 12 is moved, so that the embroidery pattern 13 corresponds to the embroidery data. Is realized.
[0045]
Reference numeral 14 denotes a rotation transmission mechanism provided on the side frame 3 of the embroidery machine 1. The rotation transmission mechanism 14 is rotatably provided on the side frame 3 and is connected to the main shaft 7 via a joint 15. A rotating shaft 16, a drive-side pulley 17 that is fixed to the rotating shaft 16 and rotates integrally with the rotating shaft 16, and is positioned below the pulley 17 and can be rotated together with the rotating shaft 18 on the side frame 3. And a timing belt 20 wound between the pulleys 17 and 19.
[0046]
The driven rotary shaft 18 is connected to an input shaft 42 of a differential device 40, which will be described later, via a joint 21. The input shaft 42 transmits the rotation of the main shaft 7 using the rotation transmission mechanism 14. The main shaft 7 is rotated at the same rotational phase.
[0047]
Further, in the differential device 40, an output shaft 44 described later is connected to another rotating shaft 23 via the joint 22, and the rotating shaft 23 is connected to a shuttle shaft 29 of the rotating shuttle 25 described later with a bevel gear (not shown). ) Etc. to transmit the rotational force. The shuttle shaft 29 is configured to rotate twice while the rotating shaft 23 rotates once by these bevel gears and the like.
[0048]
Reference numeral 24 is a hook holder provided on the base 2 below the head portion 6, and 25 is a rotary hook rotatably mounted in the hook holder 24. The rotary hook 25 is shown in FIGS. 5, an outer hook 26 having a boss portion 26A to which a hook shaft 29 described later is attached, and a bobbin (not shown) for lower thread disposed in the outer hook 26 so as to be relatively rotatable. The hook 27 and the bobbin case 28 that holds the bobbin for the lower thread in the inner hook 27 are generally configured.
[0049]
Here, the inner hook 27 has a support shaft 27A on the center side, and a bobbin for lower thread is rotatably mounted on the support shaft 27A together with the bobbin case 28. A needle hole 27B is formed on the outer peripheral side of the inner hook 27, and the sewing needle 12 is inserted into the needle hole 27B with an upper thread.
[0050]
On the other hand, the outer hook 26 is provided with a sword tip 26B as shown in FIG. The sword tip 26B rotates in the direction indicated by the arrow M together with the outer hook 26, thereby hooking the upper thread inserted by the needle point of the sewing needle 12 into the needle hole 27B of the inner hook 27 (the thread hooking point θd1 in FIG. 9). ) The upper thread is taken into the rotary hook 25.
[0051]
As a result, the upper thread forms a so-called “seam”, so that the upper thread becomes entangled with the lower thread in the inner hook 27 as the outer hook 26 rotates (the thread dropout point θg1 in FIG. 9). The upper thread completely comes out of the rotary hook 25 at the hook removal point θh1.
[0052]
Reference numeral 29 denotes a hook shaft constituting a part of the rotary hook 25. The hook shaft 29 is fitted in the boss portion 26A of the outer hook 26 as shown in FIG. 4, and can be attached to and detached from the outer hook 26 using a screw 30 or the like. It is fixed to. The shuttle shaft 29 rotates twice while the rotary shaft 23 shown in FIG. 2 makes one rotation, as described above, and rotationally drives the outer shuttle 26 in the direction indicated by the arrow M in FIGS.
[0053]
Here, the hook shaft 29 is positioned with the screw 30 or the like with respect to the boss portion 26A of the outer hook 26 so that the rotational phase of the rotary hook 25 changes starting from the needle bottom dead center θc shown in FIG. Accordingly, the outer hook 26 is rotationally driven so that the sword tip 26B moves up and down along the characteristic line Sk1 shown in FIGS.
[0054]
Next, the differential device 40 employed in the present embodiment will be described in detail with reference to FIGS. 2 and 6 to 8. In this case, the differential device 40 is installed on the base 2 of the embroidery machine 1 as shown in FIG. 2, and changes the rotational phase between the rotary shafts 18 and 23 as described later.
[0055]
41 is a casing that forms the outer shell of the differential device 40, and the casing 41 includes a bottom plate portion 41A that is fixed on the base 2 of the embroidery machine 1, as shown in FIGS. The bottom plate portion 41A is composed of front and rear side plate portions 41B and 41C and left and right side plate portions 41D and 41E which are erected upward from the upper surface of the bottom plate portion 41A, and is formed as a bottomed rectangular tube as a whole. .
[0056]
An input shaft 42 is rotatably provided on the casing 41. The input shaft 42 is supported on the left side plate portion 41D via a bearing case 43 and the like, and is also rotatable with respect to an intermediate bearing case 46 described later. Installed on. The projecting end side of the input shaft 42 projecting out of the casing 41 is connected to the rotary shaft 18 via the joint 21 as shown in FIG. 2, and the main shaft 7 is operated at a substantially constant speed as indicated by the arrow A in FIG. It is rotated at a constant speed in the direction.
[0057]
Reference numeral 44 denotes an output shaft that is axially spaced from the input shaft 42 and is rotatably provided in the casing 41. The output shaft 44 is supported by the right side plate portion 41E via a bearing case 45 and the like, The bearing case 46 is also rotatably attached.
[0058]
The output shaft 44 is disposed at a position that is substantially coaxial with the input shaft 42 via the intermediate bearing case 46, and the projecting end side that projects out of the casing 41 is a rotating shaft via the joint 22 as shown in FIG. 23 is connected.
[0059]
An intermediate bearing case 46 is disposed between the input shaft 42 and the output shaft 44 and is disposed in the casing 41. The intermediate bearing case 46 is formed as a stepped cylindrical body as shown in FIGS. The outer peripheral side is fixed to the side plate portion 41B or 41C of the casing 41 via a bracket (not shown) or the like. The intermediate bearing case 46 supports the input shaft 42 and the output shaft 44 located on both sides in the axial direction so as to be relatively rotatable via bearings.
[0060]
Reference numeral 47 indicates a phase difference generating mechanism disposed between the input shaft 42 and the output shaft 44. The phase difference generating mechanism 47 includes an intermediate shaft 48, helical gears 49 and 51, a cam device 55, and the like which will be described later. It is comprised by.
[0061]
An intermediate shaft 48 is provided in the casing 41 so as to be radially separated from the input shaft 42 and the output shaft 44. The intermediate shaft 48 is fixed to the left and right side plate portions 41D and 41E on the left and right ends, and will be described later. The helical gear 51, the spur gear 52 and the cam wheel 56 are supported so as to be rotatable and slidable in the axial direction.
[0062]
Reference numeral 49 denotes a first helical gear which is located in the casing 41 and is provided on the input shaft 42. The helical gear 49 has a stopper cylinder 49A, which is connected to the input shaft 42 by the stopper cylinder 49A. It is fixed integrally. The first helical gear 49 meshes with the second helical gear 51 that is the counterpart, and both are formed with the same number of teeth, pitch circle diameter D, helix angle β, and the like.
[0063]
Reference numeral 50 denotes a cylinder that is located between the helical gear 49 and the intermediate bearing case 46 and is fitted on the outer peripheral side of the input shaft 42, and the cylindrical body 50 is in contact with the end face of the helical gear 49. This restricts the input shaft 42 and the helical gear 49 and the like from being displaced in the axial direction within the casing 41.
[0064]
A second helical gear 51 is slidably fitted with the cam wheel 56 on the outer peripheral side of the intermediate shaft 48, and the second helical gear 51 meshes with the first helical gear 49. Then, the first helical gear 49 rotates in the opposite direction (the direction indicated by the arrow B in FIG. 6). And these helical gears 49 and 51 rotate with mutually different rotational phases within the range of the maximum phase angle ψ as shown in the following formula 1 by changing the meshing position between the tooth surfaces. .
[0065]
[Expression 1]
ψ = S × tan β × 360 / (π × D)
However, D: Pitch circle diameter of helical gear
β: Helix angle of helical gear
S: Cam wheel offset
[0066]
52 is a spur gear as a gear member slidably fitted together with a helical gear 51 and a cam wheel 56 on the outer peripheral side of the intermediate shaft 48. The spur gear 52 meshes with a spur gear 53 to be described later. The spur gears 52 and 53 rotate in opposite directions with the same rotational phase.
[0067]
53 is another spur gear as a gear member which is located in the casing 41 and provided on the output shaft 44. The spur gear 53 has the same gear shape as the spur gear 52 on the intermediate shaft 48 side. 52. The spur gear 53 has a stopper cylinder 53A, and is fixed integrally to the output shaft 44 by the stopper cylinder 53A. The spur gear 53 rotates integrally with the output shaft 44.
[0068]
Reference numeral 54 denotes another cylindrical body that is located between the intermediate bearing case 46 and the spur gear 53 and is fitted on the outer peripheral side of the output shaft 44, and the cylindrical body 54 abuts against an end surface of the spur gear 53. Thus, the displacement of the output shaft 44 and the spur gear 53 in the axial direction in the casing 41 is restricted.
[0069]
Reference numeral 55 denotes a cam device as differential cam means constituting a part of the phase difference generating mechanism 47, and the cam device 55 includes a cam wheel 56 and a cam follower 57 which will be described later.
[0070]
A cam wheel 56 is slidably fitted together with the helical gear 51 and the spur gear 52 on the outer peripheral side of the intermediate shaft 48. The cam wheel 56 is arranged between the helical gear 51 and the spur gear 52. A cam groove 56A extending obliquely according to a sine curve having an offset amount S as shown in FIG.
[0071]
The cam wheel 56 is slidably displaced in the directions indicated by arrows C and C ′ in FIG. 6 according to the rotation of the input shaft 42 by engaging the cam groove 56A with the cam follower 57 as shown in FIG. .
[0072]
Reference numeral 57 denotes a cam follower provided on the side plate portion 41C on the rear side of the casing 41 via a cylindrical holder 58. The cam follower 57 is composed of a rotatable roller or the like and is always engaged with a cam groove 56A of the cam wheel 56. ing. Then, the cam follower 57 converts the rotation of the cam wheel 56 into an axial sliding displacement according to the shape of the cam groove 56A, and the cam wheel 56 together with the helical gear 51 and the spur gear 52 in FIG. It is slid and displaced in the directions of arrows C and C ′.
[0073]
The embroidery machine 1 including the differential device 40 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.
[0074]
First, when the main shaft 7 is rotationally driven by the main shaft motor of the embroidery machine 1, the rotation of the main shaft 7 is transmitted to the balance 10 via the balance driving section in the head section 6, and the balance 10 is represented by the characteristic line St shown in FIG. It is driven to move up and down along.
[0075]
When the balance 10 is driven downward (between the top dead center θa of the balance and the bottom dead center θf of the balance in FIG. 9), the upper thread is slightly slackened with the sewing machine needle 12. Thus, the upper thread is fed to the sewing needle 12 side.
[0076]
When the balance 10 is driven upward (between the bottom dead center θf of the balance in FIG. 9 and the next top dead center θa of the balance), the stitches and threads formed on the embroidery cloth 13 by the sewing needle 12 are used. A tension is applied to the upper thread so as to pull the upper thread between the tension 9 and the like, and the balance 10 tightens the seam and feeds the upper thread.
[0077]
At this time, on the lower end side of the head part 6, the needle bar 11 is reciprocated up and down as indicated by the characteristic line Sh in FIG. The sewing needle 12 is moved with respect to the embroidery cloth 13.
[0078]
That is, the needle bar 11 is moved from the position of the needle top dead center θ0 (for example, θ0 = 0 °) to the needle bottom dead center θc (for example, θc = 180 °) with respect to the rotational angle θ of the main shaft 7 together with the sewing needle 12. It is driven downward to the position, and thereafter it is driven upward from the position of the needle bottom dead center θc to the position of the angle θi (for example, θi = 360 °) to reach the needle top dead center again.
[0079]
The sewing needle 12 moved up and down by the needle bar 11 is driven along the characteristic line Sh in the same manner as the needle bar 11, and the needle tip is embroidered at the needle entry point θb (for example, θb = 115 °). The cloth 13 passes through the cloth 13 and enters the rotary hook 25 (the needle hole 27B of the inner hook 27). Thereafter, the needle tip comes out of the embroidery cloth 13 at the needle removal point θe (for example, θe = 250 °). Is.
[0080]
Then, while the sewing needle 12 is positioned above the embroidery cloth 13 (while reaching the needle entry point θb from the needle top dead center θ0 in FIG. 9 and the needle top dead center next to the angle θi from the needle withdrawal point θe. The embroidery cloth 13 is moved to the front, rear, left, and right in the horizontal direction together with the holding frame, so that the embroidery cloth 13 is moved in accordance with the movement of the sewing needle 12. An embroidery pattern is created.
[0081]
At this time, the rotation of the main shaft 7 is transmitted to the differential device 40 through the rotation transmission mechanism 14, and a phase difference is generated between the input shaft 42 and the output shaft 44 of the differential device 40 as described later. The rotation having this phase difference is transmitted to the hook shaft 29 of the rotary hook 25 via the rotary shaft 23, so that the rotational phase of the hook shaft 29 is appropriately adjusted with respect to the main shaft 7 as described later. It is possible to finish the seam beautifully.
[0082]
Therefore, the operation of the differential device 40 will be described with reference to FIGS. 6 to 8. First, when the input shaft 42 is rotationally driven in the direction of arrow A in FIG. The helical gear 49 rotates as a unit, and this rotation is transmitted to the opposite helical gear 51 as a rotation in the opposite direction (arrow B direction).
[0083]
At this time, since the cam wheel 56 rotates integrally with the helical gear 51, the rotation of the cam wheel 56 is converted into an axial displacement by the cam follower 57 engaged with the cam groove 56A. Together with the gear 51 and the spur gear 52, they are slid and displaced in the directions indicated by arrows C and C 'in FIG.
[0084]
As a result, the helical gears 49 and 51 meshing with each other change the meshing position between the two gears according to the axial displacement of the helical gear 51. For example, the helical gear 51 is indicated by an arrow C in FIG. When displaced in the direction, the helical gear 51 rotates relative to the helical gear 49 so as to advance the rotational phase, and a phase difference in the leading direction is generated between the helical gears 49 and 51.
[0085]
When the helical gear 51 is displaced together with the cam wheel 56 in the direction of the arrow C ′ in FIG. 6, the helical gear 51 rotates relative to the helical gear 49 so as to delay the rotational phase. A phase difference in the slow direction occurs between the helical gears 49 and 51. During this time, since the spur gear 52 and the spur gear 53 continue to mesh with each other at the same rotational phase, the output shaft 44 rotates with respect to the input shaft 42 with the same phase difference as between the helical gears 49 and 51. become.
[0086]
As a result, when the input shaft 42 rotates at a substantially constant speed (for example, 360 degrees in 4 t seconds) along the characteristic line 60 shown by a solid line in FIG. 8, the output shaft 44 is shown by a two-dot chain line in FIG. Rotate at a non-uniform speed so as to draw a curved curve along the characteristic line 61 shown in FIG.
[0087]
When the rotational phase of the input shaft 42 and the output shaft 44 are substantially the same at the positions of 0 degrees, 180 degrees, and 360 degrees, the rotational phase of the input shaft 42 reaches 90 degrees at time t seconds. The rotational phase of the output shaft 44 advances by an angle substantially corresponding to the maximum phase angle ψ. Further, when the rotational phase of the input shaft 42 reaches 270 degrees at the time of 3 tsec, the rotational phase of the output shaft 44 is delayed by an angle substantially corresponding to the maximum phase angle ψ.
[0088]
That is, while the cam wheel 56 is displaced in the arrow C direction from the initial position shown in FIG. 6 (for example, in the range of the rotation phase 0 to 180 degrees shown in FIG. 8), the input shaft 42 and the output shaft 44 During which the cam wheel 56 is displaced from the position shown in FIG. 6 in the direction indicated by the arrow C ′ (for example, a rotational phase range of 180 to 360 degrees shown in FIG. 8). ), A phase difference in the slow direction occurs between the input shaft 42 and the output shaft 44.
[0089]
Here, the output shaft 44 of the differential device 40 is connected to the rotary shaft 23 via the joint 22 as shown in FIG. 2, and the rotary shaft 23 is connected to the shuttle shaft 29 of the rotary shuttle 25 via a bevel gear or the like. As a result, the rotary shaft 29 rotates twice while the rotary shaft 23 makes one rotation.
[0090]
Then, when the rotational phase of the input shaft 42 (main shaft 7) illustrated in FIG. 8 is 270 degrees, that is, when the cam wheel 56 shown in FIG. 6 is displaced maximum in the arrow C ′ direction, FIG. For example, the rotary shaft 18 and the input shaft 42 are connected by the joint 21 so that the needle bar 11 (sewing needle 12) shown in FIG. 9 reaches the bottom dead center position (needle bottom dead center θc in FIG. 9). In this case, the main shaft 7 and the rotary shaft 16 may be connected by the joint 15 so as to satisfy the above-described conditions.
[0091]
As a result, the output shaft 44 of the differential device 40 is adjusted so that the rotational phase is advanced with respect to the input shaft 42. Since the input shaft 42 rotates with the same rotational phase as the main shaft 7, the input shaft 42 rotates along the characteristic line Sh of the needle bar 11 indicated by a solid line in FIG. 10, and the output shaft 44 in FIG. It rotates along the characteristic line Sh1 indicated by a two-dot chain line.
[0092]
Also, the output shaft 44 and the rotary shaft 23 shown in FIG. 2 are connected by the joint 22 with their rotational positions adjusted, and the hook shaft 29 and the boss portion 26A of the outer hook 26 shown in FIG. In the meantime, they are connected using screws 30 or the like with their rotational positions properly adjusted.
[0093]
As a result, the hook shaft 29 is positioned with the screw 30 or the like with respect to the boss portion 26A of the outer hook 26 so that the rotational phase of the rotary hook 25 changes, for example, starting from the needle bottom dead center θc shown in FIG. The outer hook 26 is rotationally driven so that the sword tip 26B moves up and down along a characteristic line Sk1 indicated by a solid line in FIGS.
[0094]
The rotational phase of the hook shaft 29 realized by using the differential device 40 is obtained by setting the needle bottom dead center θc to the characteristic line Sk of the conventional hook shaft illustrated by the one-dot chain line in FIGS. 9 and 10. The rotation phase of the rotary hook 25 is adjusted as a starting point. The phase of the characteristic line Sk1 and the characteristic line Sk coincide at the position of the needle bottom dead center θc, but at the rotational position before and after, the hook shaft 29 The rotational phase is relatively advanced.
[0095]
Thus, according to the present embodiment, when the hook shaft 29 is rotated along the characteristic line Sk1 shown in FIGS. 9 and 10, the thread hook point θd1 (for example, θd1 = 202 °) is reached. The upper thread can be hooked and taken into the rotary hook 25 by the sword tip 26B of 26, and then the thread hook point θg1 (for example, θg1 = 303 °) at which the upper thread ends entangled with the lower thread is reached by the rotary hook 25, The upper thread can be completely removed from the rotary hook 25 at the point θh1 (for example, θh1 = 342 °).
[0096]
When the characteristic line Sk1 according to the present embodiment is compared with the characteristic line Sk of the prior art, the phase difference ψ1 (for example, as shown in FIG. The leading phase can be set by ψ1 = about 12 °), and the hook phase θh1 can also be set to the phase advanced by phase difference ψ2 (for example, ψ2 = about 16 °) compared to the conventional hook point θh. Can do.
[0097]
As a result, the sewing tone of the embroidery cloth 13 by the embroidery machine 1 can be changed according to the operating characteristics from the thread threading point θd1 of the upper thread by the rotary hook 25 to the hook removal point θh1, and the hook shaft 29 and the balance 10, The embroidery quality can be improved by optimizing the relative operation characteristics with the needle bar 11.
[0098]
Further, as indicated by the characteristic line Sk1 shown in FIGS. 9 and 10, the timing from the thread removal point θg1 to the hook removal point θh1 is set to a lead phase, so that the timing at which the upper thread is pulled up by the balance 10 is relatively delayed. Thus, the upper thread can be pulled up relatively slowly, reducing the possibility of thread breakage, improving thread tightening and the like, and making the embroidery stitches beautiful.
[0099]
In this case, it is possible to relatively slow the timing at which the upper thread is pulled up by the balance 10 without lowering the rotational speed of the main shaft 7, so that the embroidery work can be executed while keeping the embroidery speed fast, and the workability is improved. This can improve the production efficiency.
[0100]
Further, when forming a seam having a large swing width, even if the frame movement amount is increased by accelerating the frame movement by the holding frame of the embroidery cloth 13, the hook shaft 29 is moved up before reaching the thread removal point θg1. The possibility that the thread will be pulled can be reduced, and the slack of the upper thread can be afforded, and problems such as thread breakage and excessive deterioration of the embroidery quality due to excessive seam tightening can be solved. Can do.
[0101]
Therefore, according to the present embodiment, by incorporating the differential device 40 between the main shaft 7 and the shuttle shaft 29 of the embroidery machine 1, the rotational phase of the shuttle shaft 29 relative to the main shaft 7 can be changed, and the embroidery cloth The 13 stitches can be finished beautifully and the embroidery quality can be effectively improved.
[0102]
Further, according to the present embodiment, by providing the differential device 40 in the embroidery machine 1, the timing of thread removal and hook removal can be advanced, and the upper thread can be pulled up with the balance 10 without difficulty. For example, even if the embroidery pattern has a large sewing width or swinging width, it can prevent the upper thread from being pulled out excessively, and can reduce the thread tension by 30 to 40 g (100 to 150 g in the prior art). The sewing needle 12 can be moved at high speed.
[0103]
Then, by speeding up the rotation phase of the rotary hook 25 and relatively slowing the timing of the balance 10, the yarn tension can be reduced and the frictional resistance of the upper yarn generated in the middle of the yarn path can be reduced. The needle can be moved without damaging it, and it is possible to realize high-quality embroidery and sewing with high speed at a high speed with moderate thread tightening and without thread breakage.
[0104]
Further, when sewing thick cloth or leather, or embroidery, the thread tension is usually increased because a thick thread is used. However, in the present embodiment, by providing the differential device 40, the thread tension is increased. It is possible to reduce the wear of the rotary hook 25 and the like and to realize a high-speed hand movement.
[0105]
Further, according to the present embodiment, the phase difference generating mechanism 47 is provided between the input shaft 42 and the output shaft 44 in the casing 41 of the differential device 40, and the phase difference generating mechanism 47 is connected to the input shaft 42, An intermediate shaft 48 provided in the casing 41 in a radial direction away from the output shaft 44, helical gears 49 and 51 provided between the input shaft 42 and the intermediate shaft 48, and meshed with each other; The helical gear 51 and the spur gear 52 are connected to the intermediate shaft 48 by engaging the spur gears 52 and 53 provided between the output shaft 44 and the cam follower 57 on the casing 41 side. The cam wheel 56 is slidably displaced in the axial direction.
[0106]
Therefore, when the input shaft 42 is rotationally driven by the main shaft 7 via the rotation transmission mechanism 14 or the like in the direction of arrow A in FIG. 6, the rotation of the helical gear 49 is opposite to the helical gear 51 ( By rotating the cam wheel 56 integrally with the helical gear 51, the rotation of the cam wheel 56 can be converted into an axial displacement by using the cam follower 57. Along with the helical gear 51 and the spur gear 52, they can be slidably displaced in the directions indicated by arrows C and C 'in FIG.
[0107]
As a result, the meshing position between the helical gears 49 and 51 can be changed according to the axial displacement of the helical gear 51. For example, the helical gear 51 is displaced in the direction indicated by the arrow C in FIG. Sometimes, the helical gear 51 can be rotated relative to the helical gear 49 so as to advance the rotational phase, thereby generating a phase difference in the leading direction between the helical gears 49 and 51. it can.
[0108]
When the helical gear 51 is displaced together with the cam wheel 56 in the direction of the arrow C ′ in FIG. 6, the helical gear 51 is rotated relative to the helical gear 49 so that the rotational phase is delayed. In addition, a phase difference in the slow direction can be generated between the helical gears 49 and 51. During this time, since the spur gear 52 and the spur gear 53 continue to mesh with each other at the same rotational phase, the output shaft 44 is rotated relative to the input shaft 42 with the same phase difference as between the helical gears 49, 51. Can do.
[0109]
As described above, the differential device 40 according to the present embodiment changes the rotation phase of the output shaft 44 with respect to the input shaft 42, and causes the rotation of the input shaft 42 that rotates at a constant speed to be nonuniform at the output shaft 44 side. It can be converted to rotation and output. Then, by using the phase difference generating mechanism 47 including the helical gears 49, 51, etc., the structure of the differential device 40 can be simplified, and the size and weight can be reduced.
[0110]
Further, an intermediate shaft 48 is interposed between the input shaft 42 and the output shaft 44, so that the output shaft 44 can be rotated in the same direction as the input shaft 42. 2 can be smoothly changed according to the meshing position of the helical gears 49 and 51. And the rotational phase of the output shaft 44 can be changed stably, the differential characteristics and reliability can be improved reliably, and the occurrence of abnormal noise or the like can be suppressed to a small level.
[0111]
Next, FIG. 11 and FIG. 12 show a second embodiment of the present invention. In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. It shall be. However, a feature of the present embodiment is that a third helical gear 71 and a fourth helical gear 72 are provided as a pair of gear members between the intermediate shaft 48 and the output shaft 44. It is in.
[0112]
Here, the third and fourth helical gears 71 and 72 are used in place of the spur gears 52 and 53 described in the first embodiment. These helical gears 71 and 72 are configured in the same manner as the first and second helical gears 49 and 51, and have the same number of teeth, pitch circle diameter D, helix angle β, and the like. ing.
[0113]
And these helical gears 71 and 72, as well as the helical gears 49 and 51, change the meshing position between the tooth surfaces according to the axial displacement of the cam wheel 56. They rotate with different rotational phases within the range of the phase angle ψ.
[0114]
The helical gear 72 has a stopper cylinder 72A, and is fixed integrally to the output shaft 44 by the stopper cylinder 72A. A cylindrical body 73 is inserted between the helical gear 72 and the intermediate bearing case 46 on the outer peripheral side of the output shaft 44, and the cylindrical body 73 contacts the end face of the helical gear 72. By contact, the output shaft 44 and the helical gear 72 are restricted from being displaced in the axial direction in the casing 41.
[0115]
Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment. In particular, in the present embodiment, the first and second phase difference generating mechanisms 47 are the first and the second. Since the second helical gears 49, 51 and the third and fourth helical gears 71, 72 are used, the input shaft 42, the output shaft 44, and the like, as indicated by the characteristic line 74 shown in FIG. The phase difference can be enlarged almost twice.
[0116]
That is, while the cam wheel 56 is displaced in the direction indicated by the arrow C from the initial position shown in FIG. 11 (for example, in the range of the rotation phase 0 to 180 degrees shown in FIG. 12), the helical gears 71 and 72 are As with the helical gears 49 and 51, the meshing position between the tooth surfaces changes according to the axial displacement of the cam wheel 56, so that a phase difference in the fast direction can be generated between the helical gears 49 and 51. Furthermore, a phase difference in the phase advance direction can also be generated between the helical gears 71 and 72.
[0117]
Further, while the cam wheel 56 is displaced in the direction indicated by the arrow C ′ from the initial position shown in FIG. 11 (for example, in the range of the rotational phase of 180 to 360 degrees shown in FIG. 12), the helical gears 71 and 72. Since the meshing position between the helical gears 49 and 51 changes the meshing position between the tooth surfaces according to the axial displacement of the cam wheel 56, the phase difference in the slow direction is established between the helical gears 49 and 51. Furthermore, a phase difference in the slow direction can also be generated between the helical gears 71 and 72.
[0118]
As a result, when the input shaft 42 rotates at a substantially constant speed (for example, 360 degrees in 4 t seconds) along the characteristic line 60 indicated by a solid line in FIG. 12, the output shaft 44 is indicated by a two-dot chain line in FIG. Rotate at a non-uniform speed so as to draw a curved curve along the characteristic line 74 shown in FIG.
[0119]
The input shaft 42 and the output shaft 44 have substantially the same rotational phase at positions of 0 degrees, 180 degrees, and 360 degrees, but the rotational phase of the input shaft 42 becomes 90 degrees at time t seconds. In this case, the rotational phase of the output shaft 44 can be advanced by an angle (2ψ) substantially corresponding to twice the maximum phase angle ψ.
[0120]
Further, when the rotational phase of the input shaft 42 reaches 270 degrees at the time of 3 tsec, the rotational phase of the output shaft 44 can be delayed by an angle (2ψ) that substantially corresponds to twice the maximum phase angle ψ. .
[0121]
Therefore, in the present embodiment, the rotational phase of the hook shaft 29 can be changed more greatly than in the first embodiment, and the phase differences ψ1, ψ2, etc. illustrated in FIG. By doing so, the embroidery quality can be improved.
[0122]
In the second embodiment, the third and fourth helical gears 71 and 72 are formed with the same twist angle β as that of the first and second helical gears 49 and 51. As described above, instead of this, the torsion angles of the first and second helical gears 49 and 51 and the third and fourth helical gears 71 and 72 are set to, for example, half the torsion angle β. If (β / 2) is set, the same phase difference as that according to the first embodiment can be obtained.
[0123]
Also, the twist angle of the first and second helical gears 49 and 51 or the third and fourth helical gears 71 and 72 is set to an angle (β / 2) that is half of the twist angle β. For example, a phase difference of 1.5 times can be generated as compared with the first embodiment.
[0124]
Next, FIG. 13 to FIG. 23 show a third embodiment of the present invention. The feature of this embodiment is that the differential cam means of the differential device is connected to the first and second helical gears. The first and second cam wheels that rotate integrally, and a rotating body that is provided with first and second cam followers and that rotates about a fulcrum located between the first and second cam wheels. It is in the configuration.
[0125]
In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
[0126]
In the figure, 80 is a differential device employed in the present embodiment, 81 is a casing forming the outer shell of the differential device 80, and the casing 81 is substantially the same as the casing 41 described in the first embodiment. And has a bottom plate portion 81A, front and rear side plate portions 81B and 81C, left and right side plate portions 81D and 81E, and the like.
[0127]
An input shaft 82 is rotatably provided on the casing 81. The input shaft 82 is supported by left and right side plate portions 81D and 81E via bearing cases 83 and 83, and the left and right end portions 82A thereof. , 82B protrudes outside the casing 81.
[0128]
The input shaft 82 is connected to the rotary shaft 18 illustrated in FIG. 2 through the joint 21 or the like at one end portion 82A projecting out of the casing 81, and is indicated by the arrow in FIG. It is rotated at a constant speed in the A direction. Further, a cam wheel 96 described later is fixedly provided on the other end 82B side of the input shaft 82.
[0129]
84 is a stopper cylinder provided on the outer peripheral side of the input shaft 82. The stopper cylinder 84 is positioned in the casing 81 and fixed to the input shaft 82, and is a bearing cylinder provided in the right bearing case 83 shown in FIG. It is in contact with the inner ring. The stopper cylinder 84 regulates the displacement of the input shaft 82 in the axial direction within the casing 81 together with a stopper cylinder 91A described later.
[0130]
Reference numeral 85 denotes an output shaft that is radially spaced from the input shaft 82 and is rotatably provided on the casing 81. The output shaft 85 has left and right ends on the left and right side plate portions 81D and 81E and a bearing case 86, 86 or the like.
[0131]
The projecting end side of the output shaft 85 projecting outside the casing 81 is connected to the rotary shaft 23 illustrated in FIG. 2 via the joint 22 and the like, and is driven to rotate in the same direction as the input shaft 82 (arrow A direction). Is.
[0132]
Reference numeral 87 denotes a stopper cylinder provided on the outer peripheral side of the output shaft 85. The stopper cylinder 87 is positioned in the casing 81 and fixed to the output shaft 85, and is a bearing cylinder provided in the left bearing case 86 shown in FIG. It is in contact with the inner ring. The stopper cylinder 87 regulates the displacement of the output shaft 85 in the axial direction within the casing 81 together with a stopper cylinder 94A described later.
[0133]
Reference numeral 88 denotes a phase difference generating mechanism disposed between the input shaft 82 and the output shaft 85. The phase difference generating mechanism 88 includes an intermediate shaft 89, helical gears 91 and 92, spur gears 93, which will be described later. 94, a cam device 95, and the like.
[0134]
89 is an intermediate shaft provided in the casing 81 so as to be radially separated from the input shaft 82 and the output shaft 85. The intermediate shaft 89 is provided on the left and right side plate portions 81D and 81E via a cylindrical bush 90 or the like. The left and right end portions 89 </ b> A and 89 </ b> B project outside the casing 81.
[0135]
A helical gear 92 and a spur gear 93, which will be described later, are fixedly provided on the intermediate shaft 89. The intermediate shaft 89 rotates integrally with the helical gear 92 and the spur gear 93 in the arrow B direction. Slidably displaced in the axial direction (indicated by arrows K1 and K2). Further, a cam wheel 97 described later is fixedly provided on the end 89B side of the intermediate shaft 89 protruding outside the casing 81.
[0136]
91 is a first helical gear provided in the input shaft 82 and located in the casing 81. The helical gear 91 has a stopper cylinder 91A. It is fixed integrally. The first helical gear 91 meshes with the second helical gear 92 that is the counterpart, and both of them have the same number of teeth as the helical gears 49 and 51 described in the first embodiment. It is formed with a pitch circle diameter and a twist angle.
[0137]
Reference numeral 92 denotes a second helical gear fixedly provided on the outer peripheral side of the intermediate shaft 89. The second helical gear 92 meshes with the first helical gear 91, and the first helical gear 91 It rotates in a direction opposite to the helical gear 91 (in the direction of arrow B in FIG. 13). These helical gears 91 and 92 rotate different from each other within the range of the maximum phase angle ψ which is substantially the same as that of the above equation 1 by changing the meshing position between the tooth surfaces by a cam device 95 described later. It rotates with phase.
[0138]
Reference numeral 93 denotes a spur gear as a gear member which is spaced apart from the helical gear 92 in the axial direction and fixed to the outer peripheral side of the intermediate shaft 89. The spur gear 93 meshes with a spur gear 94 which will be described later. Reference numerals 93 and 94 rotate in opposite directions at the same rotational phase.
[0139]
94 is another spur gear as a gear member provided in the output shaft 85 and located in the casing 81. The spur gear 94 has substantially the same gear shape as the spur gear 93 on the intermediate shaft 89 side. The gear 93 is engaged. The spur gear 94 has a stopper cylinder 94A, and is integrally fixed to the output shaft 85 by the stopper cylinder 94A. The spur gear 94 rotates integrally with the output shaft 85.
[0140]
Reference numeral 95 denotes a cam device as differential cam means constituting a part of the phase difference generating mechanism 88. The cam device 95 includes cam wheels 96 and 97, a support block 98, a follower support 104, and cam followers 109 and 110, which will be described later. Etc.
[0141]
Reference numeral 96 denotes a first cam wheel fixedly provided on the end portion 82B side of the input shaft 82. The cam wheel 96 is fixed to the end portion 82B of the input shaft 82 so as to rotate integrally with the helical gear 91. A cam groove 96A extending obliquely according to a sine curve of the offset amount S is formed on the outer peripheral side as shown in FIG. In this case, the offset amount S of the cam groove 96A is preferably set to about S = 10 mm, for example.
[0142]
The cam wheel 96 rotates the follower support 104 in the directions indicated by arrows J1 and J2 according to the rotation of the input shaft 82 by engaging the cam groove 96A with the cam follower 109 as shown in FIG.
[0143]
Reference numeral 97 denotes a second cam wheel fixedly provided on the end 89B side of the intermediate shaft 89. The cam wheel 97 is connected to the end of the intermediate shaft 89 so as to rotate integrally with the helical gear 92 and the spur gear 93. An annular groove 97A serving as a cam groove extending in the circumferential direction of the intermediate shaft 89 is formed on the outer peripheral side of the portion 89B.
[0144]
Then, a cam follower 110 (described later) is engaged with the annular groove 97A of the cam wheel 97 as shown in FIG. 16, so that the cam wheel 97 is integrated with the intermediate shaft 89 in the axial direction (arrows K1, K2 in FIG. 13). Direction).
[0145]
Reference numeral 98 denotes a support block disposed on the rear side of the cam wheels 96, 97. The support block 98 is provided on the bottom plate portion 81A of the casing 81 through a pedestal 99 or the like as shown in FIGS. A follower support 104 or the like is rotatably supported via a support shaft 102 described later. Further, as shown in FIG. 15, the support block 98 is formed with a long hole-like mounting hole 98A extending in the upward and downward directions.
[0146]
Reference numeral 100 denotes a slide plate mounted in the mounting hole 98A of the support block 98 using a fixing screw 101. The slide plate 100 is slidably arranged in the mounting hole 98A upward and downward (in the directions of arrows H1 and H2). And is fixed to the support block 98 using the fixing screw 101 together with the support shaft 102.
[0147]
Here, when the slide plate 100 is raised in the direction of the arrow H1 in the mounting hole 98A, the relative position of the support shaft 102 with respect to the cam followers 109 and 110 described later changes, and the support shaft 102 and the cam follower 110 shown in FIG. The distance L1 between the support shaft 102 and the cam follower 109 is adjusted to be relatively large (L2> L1).
[0148]
When the slide plate 100 is lowered in the direction indicated by the arrow H2 in the mounting hole 98A, the distance L1 between the support shaft 102 and the cam follower 110 shown in FIG. Is adjusted so as to be relatively small (L2 <L1).
[0149]
Reference numeral 102 denotes a support shaft fixed to the slide plate 100 by means such as press-fitting. The support shaft 102 is disposed at a position approximately in the middle of the cam wheels 96 and 97 as shown in FIG. 104 rotational fulcrums are configured. The support shaft 102 has a large-diameter head portion 102 </ b> A on the distal end side, and a nut 103 is screwed to a portion of the support shaft 102 in the longitudinal direction.
[0150]
The nut 103 is attached to the support shaft 102 so as to sandwich the follower support 104 with the head portion 102A, whereby the support shaft 102 rotates the follower support 104 with respect to the support block 98 (slide plate 100). It is supported movably.
[0151]
Reference numeral 104 denotes a follower support as a rotating body that converts the rotation of the cam wheel 96 into an axial displacement of the cam wheel 97. The follower support 104 includes a cam follower plate 105, a pair of holding plates 106 and 106, and a fastening bolt 108, which will be described later. It is comprised by.
[0152]
Reference numeral 105 denotes a cam follower plate to which cam followers 109 and 110 are attached. The cam follower plate 105 is provided with cylindrical attachment portions 105A and 105B spaced apart from each other upward and downward as shown in FIGS. Cam followers 109 and 110 are attached to the attachment portions 105A and 105B, respectively.
[0153]
Further, the cam follower plate 105 is formed with a long hole 105C which is positioned between the mounting portions 105A and 105B and extends upward and downward, and a spacer 107 and the like which will be described later are relative to the long hole 105C in the upward and downward directions. It is movably inserted.
[0154]
Further, the cam follower plate 105 is formed with a total of four other elongated holes 105D, 105D,... Spaced apart on both the left and right sides of the mounting portions 105A, 105B, and fastening bolts described later are formed in these elongated holes 105D. 108 is inserted so as to be relatively movable upward and downward.
[0155]
106 and 106 are a pair of holding plates for holding the cam follower plate 105 so as to be sandwiched from the front and the rear. Each holding plate 106 is formed of a substantially rectangular flat plate as shown in FIGS. A support shaft 102 is rotatably mounted using a bearing or the like.
[0156]
A cylindrical spacer 107 is disposed between the holding plates 106 and 106 on the outer peripheral side of the support shaft 102, and a thickness T of the cam follower plate 105 is provided between the holding plates 106 and 106 by the spacer 107. A gap corresponding to is formed.
[0157]
Further, the holding plate 106 is formed with notches 106A and 106B which are spaced apart above and below the support shaft 102 to form a substantially U-shape, and the mounting portion 105A of the cam follower plate 105 is formed in the notches 106A and 106B. , 105B are inserted so as to be relatively movable upward and downward.
[0158]
Further, a total of four screw holes 106C, 106C,... Are formed in the holding plate 106 on the left and right sides of the notches 106A, 106B, and fastening bolts 108 are screwed into the screw holes 106C, respectively. Is.
[0159]
108, 108,... Are fastening bolts for fixing the cam follower plate 105 between the holding plates 106, 106. Each fastening bolt 108 is a state in which the cam follower plate 105 is disposed between the holding plates 106, 106 as shown in FIG. Thus, the cam follower plate 105 is held between the holding plates 106 and 106 by being screwed into the screw holes 106C of the holding plate 106, respectively.
[0160]
Further, in a state where each fastening bolt 108 is loosened, the cam follower plate 105 can be relatively moved between the holding plates 106 and 106 along the elongated holes 105C and 105D shown in FIG. In this state, the slide plate 100 is moved up and down in the mounting hole 98A of the support block 98, so that the relative position between the support shaft 102 and the cam followers 109 and 110 (intervals L1 and L2 shown in FIG. 16). It can be variably adjusted.
[0161]
Reference numeral 109 denotes a first cam follower provided on the mounting portion 105A of the cam follower plate 105 via a nut 109A or the like. The cam follower 109 is composed of a rotatable roller or the like, and is always engaged with the cam groove 96A of the cam wheel 96. Yes. The cam follower 109 converts the rotation of the cam wheel 96 into a rotational displacement of the follower support 104 in the directions indicated by arrows J1 and J2 in accordance with the shape of the cam groove 96A.
[0162]
Reference numeral 110 denotes a second cam follower provided on the mounting portion 105B of the cam follower plate 105 via a nut 110A or the like. The cam follower 110 is also composed of a rotatable roller or the like, and is always engaged with the annular groove 97A of the cam wheel 97. Yes. The cam follower 110 converts the rotational displacement of the follower support 104 in the directions indicated by arrows J1 and J2 shown in FIG. 13 into the axial displacement of the intermediate shaft 89 (directions indicated by arrows K1 and K2 in FIG. 13). .
[0163]
Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment. For example, the cam groove 96A of the cam wheel 96 is offset by, for example, about S = 10 mm. When the amount S is set, the rotational phase of the output shaft 85 can be changed with respect to the input shaft 82 (characteristic line 60) as indicated by the characteristic line 111 shown in FIG.
[0164]
That is, in the present embodiment, when the cam wheel 96 is rotated in the direction of arrow A by the input shaft 82, the follower support 104 rotates in the direction of arrow J1 around the support shaft 102 from the initial position shown in FIG. Moved. When the follower support 104 rotates in the arrow J1 direction, the cam wheel 97 is pushed through the cam follower 110 in the arrow K1 direction in FIG.
[0165]
As a result, the intermediate shaft 89 is slidably displaced in the direction of the arrow K1 in FIG. 13 together with the helical gear 92 and the spur gear 93, and the meshing position between the helical gears 91 and 92 changes. The helical gear 92 can be rotated relative to the helical gear 91 so as to delay the rotational phase, and the intermediate shaft 89 is displaced from the initial position shown in FIG. 13 in the direction of the arrow K1 (for example, in FIG. 23). In the range of 0 to 180 degrees of the rotation phase shown in FIG.
[0166]
In this case, when the follower support 104 rotates in the arrow J1 direction, the cam wheel 97 is pushed in the arrow K1 direction in FIG. 13 via the cam follower 110. When the offset amount S of the groove 96A is S = 10 mm, the rotational phase of the output shaft 85 is delayed by an angle substantially corresponding to the maximum phase angle ψ when the rotational phase of the input shaft 82 reaches 90 degrees, for example. can do.
[0167]
When the rotational phase of the input shaft 82 exceeds 180 degrees, the follower support 104 rotates in the direction indicated by the arrow J2. At this time, the cam wheel 97 passes through the cam follower 110 in the direction indicated by the arrow K2 in FIG. Is pushed. In this case, the helical gear 92 can be rotated relative to the helical gear 91 so as to advance the rotational phase.
[0168]
While the intermediate shaft 89 is displaced in the direction indicated by the arrow K2 from the initial position shown in FIG. 13 (for example, in the range of the rotation phase of 180 to 360 degrees shown in FIG. 23), When the rotational phase of the input shaft 82 reaches, for example, 270 degrees, the rotational phase of the output shaft 85 can be advanced by an angle substantially corresponding to the maximum phase angle ψ. it can.
[0169]
In this way, the follower support 104 rotates in the directions indicated by arrows J1 and J2 along the shape of the cam groove 96A of the cam wheel 96, and the helical gear 92 is axially displaced together with the intermediate shaft 89, thereby allowing the input. A phase difference can be generated in the rotational phase between the shaft 82 and the output shaft 85, and a phase characteristic different from that of the above embodiment can be realized.
[0170]
On the other hand, with the fastening bolt 108 shown in FIG. 17 loosened, the cam follower plate 105 is relatively moved between the holding plates 106 and 106 along the long holes 105C and 105D shown in FIGS. 18 and 19, and the slide plate 100 is moved. When the support block 98 is moved up and down in the mounting hole 98A, the relative positions of the support shaft 102 and the cam followers 109 and 110 (intervals L1 and L2 shown in FIG. 16) can be variably adjusted.
[0171]
Then, the slide plate 100 is raised in the direction indicated by the arrow H1 in the mounting hole 98A, the interval L1 between the support shaft 102 and the cam follower 110 is reduced, and the interval L2 between the support shaft 102 and the cam follower 109 is increased (L2> L1). In this case, the phase difference between the input shaft 82 and the output shaft 85 can be changed so as to be reduced by a ratio (L1 / L2).
[0172]
Further, the slide plate 100 is lowered in the direction indicated by the arrow H2 in the mounting hole 98A, the interval L1 between the support shaft 102 and the cam follower 110 is increased, and the interval L2 between the support shaft 102 and the cam follower 109 is decreased (L2 <L1). In this case, the phase difference between the input shaft 82 and the output shaft 85 can be changed so as to increase by the ratio (L1 / L2).
[0173]
An arbitrary phase characteristic can be obtained by appropriately changing the total length (L1 + L2) of the intervals L1 and L2, the inclination of the cam groove 96A (offset amount S), the pitch circle diameter of the cam wheel 96, and the like. Can do.
[0174]
When the offset amount S of the cam groove 96A is larger than S = 10 mm, for example, about S = 20 mm, the position is closer to 60 degrees (300 degrees) than the position of 90 degrees (270 degrees) described above. Thus, the phase difference between the input shaft 82 and the output shaft 85 can be maximized.
[0175]
In this case, the angle at which the outer periphery of the cam follower 109 hits the peripheral wall of the cam groove 96A of the cam wheel 96 gradually changes according to the gradient (lift) of the cam groove 96A, and as described in the above embodiment, the input shaft 82 and the output shaft When the phase difference of 85 is 90 degrees and 270 degrees, the maximum phase difference cannot be obtained. For example, the maximum phase difference can be obtained at positions of about 60 degrees and 300 degrees.
[0176]
Next, FIGS. 24 to 26 show a fourth embodiment of the present invention. The feature of the present embodiment is that an intermediate shaft is provided between one input shaft and two output shafts, respectively. The rotation of the input shaft is transmitted to each intermediate shaft via a pair of gear members, and the rotation of each intermediate shaft is transmitted to each output shaft via the first and second helical gears. There is.
[0177]
In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
[0178]
In the figure, 120 is a differential device adopted in the present embodiment, 121 is a casing forming the outer shell of the differential device 120, and the casing 121 is substantially the same as the casing 41 described in the first embodiment. And has a bottom plate portion 121A, front and rear side plate portions 121B and 121C, left and right side plate portions 121D and 121E, and the like.
[0179]
An input shaft 122 is rotatably provided on the casing 121. The input shaft 122 is supported on left and right side plate portions 121D and 121E via bearing cases 123 and 123, etc. on both left and right ends. The projecting end side of the input shaft 122 projecting outside the casing 121 is connected to the main shaft 7 via a rotation transmission mechanism (not shown) or the like, for example, and the main shaft 7 indicates an arrow A in FIG. It is rotated at a constant speed in the direction.
[0180]
Reference numeral 124 denotes a stopper cylinder provided on the outer peripheral side of the input shaft 122. The stopper cylinder 124 is located in the casing 121 and fixed to the input shaft 122, and is a bearing cylinder provided in the left bearing case 123 shown in FIG. It is in contact with the inner ring. The stopper cylinder 124 restricts the axial displacement of the input shaft 122 in the casing 121 together with a stopper cylinder 134A described later.
[0181]
Reference numerals 125 and 126 denote output shafts that are spaced from the input shaft 122 in the radial direction and are rotatably provided on the casing 121. The output shafts 125 and 126 have left and right side plate portions 121D and 121E on the left and right ends, respectively. Are supported via bearing cases 127, 127,.
[0182]
The output shafts 125 and 126 are connected to the external drive object, for example, the drive shaft (not shown) of the balance 10, the rotary shaft 23 (the shuttle shaft 29) illustrated in FIG. Are separately connected to each other, and are rotationally driven in the same direction as the input shaft 122 (in the direction of arrow A).
[0183]
Reference numerals 128 and 128 denote stopper cylinders provided on the outer peripheral sides of the output shafts 125 and 126. The stopper cylinders 128 are positioned in the casing 121 and fixed to the output shafts 125 and 126, and the right bearing case shown in FIG. 127 is in contact with an inner ring of a bearing provided in 127. Each stopper cylinder 128 regulates axial displacement of the output shafts 125 and 126 in the casing 121 together with stopper cylinders 139A and 140A described later.
[0184]
Reference numerals 129 and 130 denote phase difference generating mechanisms disposed between the input shaft 122 and the output shafts 125 and 126. The phase difference generating mechanisms 129 and 130 include intermediate shafts 131 and 132, spur gears 134, 135, 136, helical gears 137, 138, 139, 140, cam devices 141, 142, and the like.
[0185]
131 and 132 are intermediate shafts provided in the casing 121 so as to be radially separated between the input shaft 122 and the output shafts 125 and 126. The intermediate shafts 131 and 132 are left and right side plates on both left and right ends. The parts 121D and 121E are attached via a cap 133 and the like.
[0186]
The intermediate shafts 131 and 132 support spur gears 135 and 136, helical gears 137 and 138, and cam wheels 143 and 144, which will be described later, in the casing 121 so as to be rotatable and slidable in the axial direction. Is.
[0187]
Reference numeral 134 denotes a spur gear as a gear member provided in the input shaft 122 located in the casing 121. The spur gear 134 meshes with spur gears 135 and 136 described later, and the spur gear 134 and the spur gears 135 and 136 are connected to each other. Are rotating in opposite directions with the same rotational phase. The spur gear 134 has a stopper cylinder 134A, and is fixed integrally to the input shaft 122 by the stopper cylinder 134A.
[0188]
Reference numerals 135 and 136 denote other spur gears as gear members provided in the intermediate shafts 131 and 132 located in the casing 121. The spur gears 135 and 136 are substantially the same as the spur gear 134 on the input shaft 122 side. Each has a shape and meshes with a spur gear 134. The spur gears 135 and 136 rotate integrally with the intermediate shafts 131 and 132, respectively.
[0189]
Reference numerals 137 and 138 denote first helical gears which are slidably fitted together with the cam wheels 143 and 144 on the outer peripheral side of the intermediate shafts 131 and 132. The first helical gears 137 and 138 will be described later. The second helical gears 139 and 140 mesh with each other and rotate in a direction opposite to the second helical gears 139 and 140 (in the direction indicated by an arrow B in FIG. 24).
[0190]
Reference numerals 139 and 140 denote second helical gears located in the casing 121 and provided on the output shafts 125 and 126. The helical gears 139 and 140 have stopper cylinders 139A and 140A, respectively. 139A and 140A are integrally fixed to the output shafts 125 and 126.
[0191]
The second helical gears 139 and 140 mesh with the first helical gears 137 and 138 which are counterparts, and these helical gears 137 and 139 (138 and 140) mesh with each other. By changing the position, the rotation is performed with different rotational phases within the range of the maximum phase angle ψ as shown in the equation (1).
[0192]
Here, the helical gears 137, 139 (138, 140) are formed with the same number of teeth, pitch circle diameter, etc., as in the helical gears 49, 51 described in the first embodiment. ing.
[0193]
However, the helical gears 137 and 139 and the helical gears 138 and 140 have different torsion angles, for example, so that the rotational phase of the helical gear 140 is different from that of the helical gear 139 as described later. Is possible.
[0194]
141 and 142 are cam devices as differential cam means constituting a part of the phase difference generating mechanisms 129 and 130. The cam devices 141 and 142 include cam wheels 143 and 144 and cam followers 145 and 146, which will be described later. Has been.
[0195]
143 and 144 are cam wheels slidably fitted together with spur gears 135 and 136 and helical gears 137 and 138 on the outer peripheral side of the intermediate shafts 131 and 132. The cam wheels 143 and 144 are spur gears 135, 136 and helical gears 137 and 138 are arranged, and cam grooves 143A and 144A extending obliquely with an offset amount S are formed on the outer peripheral side thereof as illustrated in FIG.
[0196]
However, since the cam wheels 143 and 144 have different cam grooves 143A and 144A, the rotational phases of the output shafts 125 and 126 (helical gears 139 and 140) can be made different from each other as will be described later. It becomes.
[0197]
The cam wheels 143 and 144 are slidably displaced in the directions indicated by arrows C and C ′, respectively, according to the rotation of the input shaft 122 by engaging the cam grooves 143A and 144A with the cam followers 145 and 146, respectively. .
[0198]
Reference numerals 145 and 146 denote cam followers provided on the side plate 121C on the rear side of the casing 121 via a cylindrical holder 147 and the like. The cam followers 145 and 146 are composed of rotatable rollers or the like, and cams of the cam wheels 143 and 144 are provided. The grooves 143A and 144A are always engaged.
[0199]
The cam followers 145 and 146 convert the rotation of the cam wheels 143 and 144 into sliding displacements in the axial direction in accordance with the shapes of the cam grooves 143A and 144A, and the cam wheels 143 and 144 are rotated by the spur gears 135 and 136. The gears 137 and 138 are slidably displaced in the directions indicated by arrows C and C ′ in FIG.
[0200]
Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In particular, in the present embodiment, the rotation of the input shaft 122 is caused by the phase difference including the intermediate shafts 131 and 132, the spur gears 134, 135, and 136, the helical gears 137, 138, 139, and 140, the cam devices 141 and 142, and the like. The generating mechanisms 129 and 130 transmit to the output shafts 125 and 126, respectively.
[0201]
Therefore, for example, by making the torsion angles of the helical gears 137 and 139 different from the helical gears 138 and 140, the output shafts 125 and 126 can be rotated with different phase differences from the input shaft 122, and the output shaft The outputs of the rotational phases different from each other can be taken out from 125 and 126.
[0202]
The output shaft 125 is connected to the drive shaft of the balance 10 so that the balance 10 can be driven up and down along the characteristic line St1 shown by a solid line in FIG. On the other hand, for example, the phase can be advanced in a range from the thread drop point θg1 to the hook drop point θh1.
[0203]
In this case, the drive shaft of the balance 10 is connected to the output shaft 125 so that the position near the yarn hooking point θd1 (for example, the position where the rotation angle θ of the main shaft 7 is about 200 degrees) is the starting point, and the thread is removed. The phase is set to advance about 10 degrees, for example, in the range from the point θg1 to the hook removal point θh1.
[0204]
The other output shaft 126 is connected to the rotary shaft 23 on the side of the shuttle shaft 29, etc., in substantially the same manner as in the first embodiment. The outer hook 26 can be driven to rotate so as to move the sword tip 26B up and down.
[0205]
As a result, the operating characteristics of the upper hook from the thread hooking point θd1 to the hook pull-out point θh1 by the rotary hook 25 can be changed, and the speed at which the balance 10 pulls the upper thread during this time can be adjusted to increase the hook shaft 29. The embroidery quality can be improved by optimizing the relative motion characteristics of the balance 10 and the needle bar 11.
[0206]
Further, as shown by the characteristic line Sk1 shown in FIG. 26, the timing from the thread removal point θg1 of the rotary hook 25 to the hook removal point θh1 is set to the advanced phase, and the timing at which the upper thread is pulled up by the balance 10 as shown by the characteristic line St1. Since the speed can be increased and the pulling speed can be increased, it is possible to increase the speed when moving the holding frame of the embroidery cloth 13 and the like, and the workability can be improved by increasing the embroidery speed.
[0207]
In addition, when forming a seam with a large swing width, even if the amount of movement of the holding frame or the like is increased, it is possible to provide a slack in the upper thread and prevent occurrence of thread breakage, The seam tightening can be optimized to improve the quality of the embroidery, and the stitching of the embroidery can be made beautiful.
[0208]
In addition, such effects can be obtained by making the cam grooves 143A, 144A of the cam wheels 143, 144 different from each other, and making the starting positions of the rotational positions of the cam wheels 143, 144 different from each other. Outputs having different rotational phases can be taken from the output shafts 125 and 126.
[0209]
Furthermore, since the differential device 120 is used to change not only the rotational phase of the rotary hook 25 (hook shaft 29) but also the phase of the balance 10, the phases of the balance 10 and the hook shaft 29 relative to the main shaft 7 are changed. The timing can be adjusted optimally, for example, the phase of the rotary hook 25 can be advanced, and the timing of the balance 10 can be relatively delayed.
[0210]
As a result, the thread tension can be reduced to reduce the frictional resistance of the upper thread that occurs in the middle of the yarn path, so that the needle can be moved without damaging the upper thread, with proper thread tightening, without thread breakage, Glossy high quality embroidery and sewing can be realized at high speed.
[0211]
Further, when sewing thick cloth or leather, or embroidery, the thread tension is usually increased because a thick thread is used. However, in the present embodiment, by providing the differential device 120, the thread tension is increased. It is possible to reduce the wear of the rotary hook 25 and the like and to realize a high-speed hand movement.
[0212]
Next, FIG. 27 shows a fifth embodiment of the present invention. In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. To do. However, the present embodiment is characterized in that a differential device 153 is provided between the spindle motor 151 and the needle drive unit 152, and the needle drive unit 152 is driven at a rotational phase different from that of the spindle motor 151 by the differential device 153. It is in the configuration to do.
[0213]
Here, the main shaft motor 151 drives a main shaft (not shown) similar to the main shaft 7 described in the first embodiment, and transmits the rotation of the main shaft to the needle driving unit 152 (the needle bar driving unit). Thus, the needle drive unit 152 reciprocates the needle bar 11 together with the sewing needle 12 up and down.
[0214]
In addition, another differential device 154 is provided on the output side of the differential device 153, and the differential device 154 has one input shaft as in the differential device 120 described in the fourth embodiment. In contrast, two output shafts (both not shown) are provided. The differential device 154 has an input shaft connected to the output side of the differential device 153, and the two output shafts are connected to the drive unit of the balance 10 and the drive unit of the shuttle shaft 29 as in the fourth embodiment. It is connected to.
[0215]
Thus, also in the present embodiment configured as described above, the relative operation characteristics of the shuttle shaft 29 and the balance 10 can be optimized by using the differential device 154, and the operation is almost the same as that of the fourth embodiment. An effect can be obtained.
[0216]
  In the present embodiment, the differential drive unit 153 provided between the spindle motor 151 and the needle drive unit 152 is configured to drive the needle drive unit 152 at a rotational phase different from that of the spindle motor 151. The needle entry point illustrated in 9θNeedle removal point from bθThe operating characteristic of the needle bar 11 can be changed so that the interval until e is shortened without changing the needle stroke and the time during which the sewing needle 12 is positioned above the embroidery cloth 13 is lengthened.
[0217]
As a result, while the sewing needle 12 is pulled upward from the embroidery cloth 13, it is possible to take a longer time to move the embroidery cloth 13 together with the holding frame to the front, back, left and right. Even for a wide embroidery pattern or the like, the timing of frame movement can be secured sufficiently to improve the embroidery quality.
[0218]
Further, when forming a seam having a large swing width, even if the amount of movement of the holding frame or the like is increased, it is possible to provide an allowance for the slack of the upper thread, thereby preventing occurrence of thread breakage. At the same time, it is possible to improve the quality of the embroidery by optimizing the seam tightness and to make the embroidery stitches beautiful.
[0219]
In the fifth embodiment, the case where the differential device 153 and the differential device 154 are separate devices has been described as an example. However, the present invention is not limited to this, and for example, in FIG. The differential unit 153 and the differential unit 154 may be incorporated in a single differential unit 161 indicated by a two-dot chain line. In this case, the differential unit 161 has one input − What is necessary is just to comprise as a differential device of 3 outputs.
[0220]
In the first embodiment, the case where the input shaft 42 and the output shaft 44 are arranged coaxially using the intermediate bearing case 46 has been described as an example. However, the present invention is not limited to this, For example, the input shaft 42 and the output shaft 44 may be arranged on different axes using two intermediate bearing cases or the like. This also applies to the other embodiments.
[0221]
Further, in the third embodiment, as illustrated in FIG. 13, the cam device 95 is provided at a position outside the side plate portion 81 </ b> E of the casing 81. Such a cam device 95 can be configured such that the entire cam device 95 can be replaced by, for example, a configuration in which the cam wheels 96 and 97 are detachably attached to the input shaft 82 and the intermediate shaft 89.
[0222]
Further, by changing the shape of the cam groove 96A (annular groove 97A as the cam groove) of the cam wheel 96 (97) or changing the torsion angle β of the helical gears 91 and 92, the input shaft and the output The rotational phase with the shaft can be increased or decreased. This also applies to the other embodiments.
[0223]
In addition, the helical gear, the spur gear, and the cam device described in each of the embodiments can be appropriately changed in combination, and various differential devices can be realized according to each combination. . In particular, by providing a cam device outside the casing, the cam device can be exchanged as a unit, and a differential device having an arbitrary phase difference can be realized.
[0224]
On the other hand, as described in the fourth embodiment, two or more output shafts may be provided for the input shaft, and the two or more output shafts are different from each other for the input shaft. It is good also as a structure which rotationally drives with a rotation phase. Further, by connecting the differential devices in a plurality of sets serially, it is possible to obtain a cooperative characteristic by changing the phase sequentially.
[0225]
Further, in the third embodiment, the total length (L1 + L2) of the above-described distances L1 and L2, the inclination of the cam groove 96A (offset amount S), the pitch circle diameter of the cam wheel 96, etc. are appropriately set. By changing to, an arbitrary phase characteristic can be obtained.
[0226]
Further, in each of the above-described embodiments, the case where the sewing machine with a differential device is applied to the embroidery machine 1 has been described as an example. However, the present invention is not limited to this, and may be applied to, for example, industrial sewing machines, household sewing machines, etc. It can be widely applied.
[0227]
【The invention's effect】
  As described in detail above, the invention described in claim 1 is directed to a differential device that rotates at least the shuttle shaft in a phase different from that of the main shaft among the needle bar, the balance, and the shuttle shaft, the casing, the input shaft, the output shaft, and the position. It consists of a phase difference generation mechanism.The phase difference generating mechanism is provided between the input shaft and the output shaft, and the intermediate shaft provided in the casing and radially spaced from the input shaft and the output shaft. The first and second helical gears for transmitting the first and second helical gears and differential cam means for relatively moving the first and second helical gears in the axial direction according to the rotation of the input shaft, , The second helical gear is provided between at least any two of the input shaft, the intermediate shaft, and the output shaft, and the differential cam means includes a cam wheel that rotates according to the input shaft, A cam follower that is provided on the casing side so as to engage with a cam wheel and that displaces the first or second helical gear in the axial direction according to the rotation of the cam wheel.Therefore, while rotating the input shaft of the differential gear according to the rotation of the main shaft, the rotation phase of the output shaft is changed with respect to the input shaft by the phase difference generation mechanism, and the rotation with the phase difference is lowered from the output shaft This can be transmitted to the hook shaft on the yarn side, and the rotation phase of the hook shaft can be changed with respect to the main shaft.
  In this case, the phase difference generating mechanism includes the first and second helical gears and differential cam means for relatively moving the first and second helical gears in the axial direction according to the rotation of the input shaft. Therefore, if the differential cam means is operated according to the rotation of the input shaft, the first and second helical gears move relative to each other in the axial direction, and the meshing position of the two changes accordingly. The rotational phase of the second helical gear can be advanced or delayed relative to the first helical gear, and the rotational phase of the output shaft can be easily changed with respect to the input shaft. Further, a helical gear can be used for the phase difference generating mechanism to simplify the structure, and the entire apparatus can be reduced in size and weight. Moreover, by interposing an intermediate shaft between the input shaft and the output shaft, the output shaft can be rotated in the same direction as the input shaft, and the rotational phases of the two shafts are changed to the first and second helical gears. Can be changed according to the meshing position.
  The differential cam means includes a cam wheel that rotates in accordance with an input shaft, and a first or second helical gear that is provided on the casing side so as to engage with the cam wheel and that rotates according to the rotation of the cam wheel. The cam follower engaged with the cam wheel can convert the rotation of the cam wheel into an axial displacement. At this time, the first helical gear or the second helical gear can be converted. By displacing the helical gear in the axial direction, the meshing position of both gears can be changed and the rotational phase can be changed smoothly.
[0228]
  Therefore, by changing the rotation phase of the shuttle shaft with respect to the main shaft, the seam can be finely finished, and the embroidery quality and the like can be improved.In addition, because the timing of thread pull-out and hook pull-out can be advanced by the differential, and the upper thread can be pulled up without difficulty by the balance, the thread tension due to the thread tension can be lowered as compared with the prior art, and the upper thread is excessive. The sewing needle can be moved at a high speed even when the handle has a large sewing width or swing width and can be prevented from being pulled out. And, since the thread tension can be reduced to reduce the frictional resistance of the upper thread that occurs in the middle of the yarn path, the needle can be moved without damaging the upper thread, with proper thread tightening, no thread breakage, and gloss High quality embroidery and sewing can be realized at high speed.
[0229]
According to the second aspect of the present invention, the differential device changes the rotation phase of the hook shaft from the position where the needle bar is at the bottom dead center, so that the rotary hook rotates with the rotation of the hook shaft. Since the upper thread and bobbin thread are entangled to change the timing at which the upper thread is removed from the rotary hook, the relative operating characteristics of the hook shaft, needle bar, and balance can be changed. After the thread is hooked and taken into the rotary hook, the upper thread and the lower thread are entangled with the rotary hook, and the timing until the upper thread is completely removed from the rotary hook can be relatively advanced. Therefore, it is possible to optimize the relative operating characteristics of the hook shaft, the balance and the needle bar, reduce the possibility of thread breakage, improve thread tightening, etc., and make the embroidery stitches beautiful. Can do.
[0233]
  Claims3The differential cam means includes a first cam wheel that rotates integrally with the first helical gear, a second cam wheel that rotates integrally with the second helical gear, A rotating body provided on the casing side and rotatable about a fulcrum located between the first and second cam wheels, and the first and second cam wheels respectively provided on the rotating body. Since it is constituted by the first and second cam followers to be engaged,The first cam follower engaged with the first cam wheel can be converted into a rotational displacement of a rotating body around a fulcrum, for example, when the first cam wheel rotates integrally with the input shaft, At this time, the second cam follower is rotationally displaced together with the rotational body. For this reason,The rotation of the first cam wheel by the first cam followerSaidThe rotation displacement of the rotating body around the fulcrum can be converted. At this time, the second cam follower is rotationally displaced together with the rotating body, and the second helical wheel is connected via the second cam wheel. While the gears are displaced in the axial direction, the meshing positions of the first and second helical gears can be changed, whereby the rotational phases of both gears can be changed stably.
[0234]
  Claims4According to the present invention, the first and second cam followers are attached to the rotating body so that the position thereof can be adjusted, and the rotating body is spaced from the first and second cam followers and the fulcrum.(L1, L2)Is variably adjusted so that the distance between the first and second cam followers and the fulcrum(L1, L2)The phase difference between the input shaft and output shaft can be separated by adjusting(L1, L2)Can be changed according to the ratio (L1 / L2), and the rotation phase can be easily changed.
[0235]
  Claims5According to the present invention, the first and second cam wheels have cam grooves having different shapes, and the first and second cam followers engage with the cam grooves of the first and second cam wheels. Since the configuration is adopted, the rotational phases of the input shaft and the output shaft can be appropriately changed according to the cam shapes of the first and second cam wheels.
[0236]
  Claims6In the invention described in the above, a plurality of output shafts are provided in the casing, and a phase difference generating mechanism is provided between each output shaft and the input shaft. Therefore, the rotation of the input shaft is controlled by each output shaft. It can be transmitted through the phase difference generation mechanism, and outputs having different rotational phases can be individually taken out from a plurality of output shafts with respect to a single input shaft.
[0237]
  Claims7According to the invention described in the above, since the plurality of output shafts are configured to transmit the rotational outputs having different phases to the balance and the hook shaft, the rotational outputs having different phases are transmitted from the respective output shafts to the balance and the hook shaft. It is possible to optimize the relative operating characteristics of the hook shaft and the balance, prevent the occurrence of thread breakage, and improve the seam tightness to finish embroidery products, sewing products, etc. neatly.
[0238]
  And claims8According to the invention described in the above, another differential device for driving the needle bar drive unit at a rotational phase different from that of the main shaft motor is provided between the main shaft motor for driving the main shaft and the drive unit for the needle bar. BecauseThe phase of the needle bar can be changed with respect to the rotational phase of the main shaft motor, and the balance and the shuttle shaft can also be rotated with different phases with respect to the main shaft motor. ThisThe operating characteristics of the needle bar can be changed so that the time for which the sewing needle is positioned above the needle plate (embroidery cloth, etc.) can be changed. It takes a long time to move. Further, when forming a seam having a large swing width, even if the amount of movement of the holding frame or the like is increased, it is possible to provide an allowance for the slack of the upper thread, thereby preventing occurrence of thread breakage. At the same time, it is possible to improve the quality of embroidery and the like by optimizing the tightness of the seams and to make the stitches beautiful.
[Brief description of the drawings]
FIG. 1 is a front view showing a sewing machine with a differential device according to a first embodiment of the present invention.
2 is an enlarged front view showing a differential, a hook holder, a rotary hook and the like in FIG. 1. FIG.
FIG. 3 is an external view showing the rotary hook in FIG. 2 as a single unit.
4 is a longitudinal sectional view of the rotary hook as seen from the direction of arrows IV-IV in FIG. 3 with the bobbin case removed.
5 is a plan view of the rotary hook shown in FIG. 4. FIG.
6 is an enlarged longitudinal sectional view showing the differential device in FIG. 1. FIG.
7 is a cross-sectional view of the differential device as seen from the direction of arrows VII-VII in FIG. 6;
8 is a characteristic diagram showing rotational phases of an input shaft and an output shaft in FIG.
FIG. 9 is a characteristic diagram showing the operating characteristics of the balance, needle bar and shuttle shaft with respect to the rotation angle of the main shaft.
FIG. 10 is an enlarged characteristic diagram showing the operating characteristics of the needle bar and shuttle shaft in FIG. 9;
FIG. 11 is a longitudinal sectional view showing a differential device according to a second embodiment.
12 is a characteristic diagram showing rotational phases of an input shaft and an output shaft in FIG.
FIG. 13 is a longitudinal sectional view showing a differential device according to a third embodiment.
14 is a right side view of the differential device showing the cam device and the like in FIG. 13;
15 is a cross-sectional view of the support block, slide plate, follower support, and the like of the cam device as seen from the direction of arrows XV-XV in FIG.
16 is a sectional view showing the cam device in an enlarged manner from the direction of arrows XVI-XVI in FIG.
17 is a cross-sectional view showing the cam device in an enlarged manner from the direction of arrows XVII-XVII in FIG.
18 is a cross-sectional view showing the follower support of the cam device in an enlarged manner from the XVIII-XVIII direction in FIG. 16;
19 is a front view showing the cam follower plate in FIG. 18 together with first and second cam followers. FIG.
20 is a sectional view showing the cam follower plate and the first and second cam followers from the direction of arrows XX-XX in FIG.
FIG. 21 is a front view showing the holding plate in FIG. 18 together with the support shaft.
22 is a cross-sectional view showing the holding plate and the support shaft from the direction of arrows XXII-XXII in FIG. 21. FIG.
FIG. 23 is a characteristic diagram showing rotational phases of the input shaft and the output shaft in FIG.
FIG. 24 is a longitudinal sectional view showing a differential device according to a fourth embodiment.
25 is a plan view of the differential device shown in FIG. 24. FIG.
FIG. 26 is a characteristic diagram showing operating characteristics of the balance and the shuttle shaft with respect to the rotation angle of the main shaft.
FIG. 27 is a configuration diagram of a sewing machine with a differential device according to a fifth embodiment;
FIG. 28 is a characteristic diagram showing operating characteristics of a balance, a needle bar and a hook shaft according to the prior art.
[Explanation of symbols]
1 Embroidery machine (sewing machine)
2 base
6 Head
7 Spindle
8 Thread hook
9 Thread tension
10 Balance
11 Needle bar
12 Sewing needle
13 Embroidery cloth
24 hook holder
25 Rotary pot
26 Outer pot
26B sword tip
27 Nakagama
29 Hook shaft
40, 80, 120, 153, 154 Differential device
41, 81, 121 casing
42, 82, 122 Input shaft
44, 85, 125, 126 Output shaft
47, 88, 129, 130 Phase difference generation mechanism
48, 89, 131, 132 Intermediate shaft
49, 91, 137, 138 First helical gear
51, 92, 139, 140 Second helical gear
52, 53, 93, 94, 134, 135, 136 spur gear (gear member)
55, 95, 141, 142 Cam device (differential cam means)
56, 143, 144 Cam wheel
56A, 96A, 143A, 144A Cam groove
57,145,146 Cam Follower
71 Third helical gear
72 4th helical gear
96 First cam wheel
97 Second cam wheel
102 Spindle (fulcrum)
104 Follower support (rotating body)
109 First cam follower
110 Second cam follower
151 Spindle motor
152 Needle drive (needle bar drive)

Claims (8)

A main shaft of the sewing machine, a balance that is driven according to the rotation of the main shaft and feeds and tightens the upper thread, a needle bar that is reciprocated according to the rotation of the main shaft, and moves the sewing needle. A difference in which at least one of the needle bar, the balance and the hook shaft rotates at a phase different from that of the main shaft, and the lower shaft side driven by the rotation of the main shaft in order to entangle the yarn and the lower thread Moving device,
The differential device includes a casing as an outer shell, an input shaft that is rotatably provided on the casing and rotated by the main shaft, and an output shaft that is rotatably provided on the casing and transmits a rotation output to at least the shuttle shaft. And a phase difference generating mechanism provided between the input shaft and the output shaft to transmit the rotation of the input shaft to the output shaft and changing the rotational phase of the output shaft with respect to the input shaft ,
The phase difference generating mechanism is provided between the input shaft and the output shaft, and an intermediate shaft provided in the casing and radially spaced from the input shaft and the output shaft. The first and second helical gears for transmission and differential cam means for relatively moving the first and second helical gears in the axial direction according to the rotation of the input shaft;
The first and second helical gears are provided between at least any two of the input shaft, the intermediate shaft, and the output shaft,
The differential cam means includes a cam wheel that rotates according to the input shaft, and the first or second helical gear that is provided on the casing side so as to be engaged with the cam wheel, according to the rotation of the cam wheel. A sewing machine with a differential device comprising a cam follower displaced in the axial direction .   The differential device changes the rotation phase of the shuttle shaft from the position where the needle bar is at the bottom dead center, whereby the upper thread and the lower thread are entangled with the rotary hook as the shuttle shaft rotates. The sewing machine with a differential device according to claim 1, wherein the timing at which the upper thread is removed from the hook is changed. A main shaft of the sewing machine, a balance that is driven according to the rotation of the main shaft and feeds and tightens the upper thread, a needle bar that is reciprocated according to the rotation of the main shaft, and moves the sewing needle. A difference in which at least one of the needle bar, the balance and the hook shaft rotates at a phase different from that of the main shaft, and the lower shaft side driven by the rotation of the main shaft in order to entangle the yarn and the lower thread Moving device,
The differential device includes a casing as an outer shell, an input shaft that is rotatably provided on the casing and rotated by the main shaft, and an output shaft that is rotatably provided on the casing and transmits a rotation output to at least the shuttle shaft. And a phase difference generating mechanism provided between the input shaft and the output shaft to transmit the rotation of the input shaft to the output shaft and changing the rotational phase of the output shaft with respect to the input shaft,
The phase difference generating mechanism is provided between the input shaft and the output shaft, and an intermediate shaft provided in the casing and radially spaced from the input shaft and the output shaft. first, second is given a helical gear, the first according to the rotation of the input shaft, the second is given constituted by a differential cam means for relatively moving the helical gear in the axial direction to convey,
The first and second helical gears are provided between at least any two of the input shaft, the intermediate shaft, and the output shaft,
The differential cam means includes a first cam wheel that rotates integrally with the first helical gear, a second cam wheel that rotates integrally with the second helical gear, and the casing side. And a rotating body that is rotatable about a fulcrum located between the first and second cam wheels, and engages with the first and second cam wheels respectively provided on the rotating body. first, second differential device with a sewing machine ing constituted by a cam follower. The first and second cam followers are attached to the rotating body so that the position can be adjusted, and the rotating body variably adjusts the distances ( L1, L2 ) between the first and second cam followers and the fulcrum. The sewing machine with a differential device according to claim 3 , which is configured. The first and second cam wheels have cam grooves of different shapes, and the first and second cam followers are configured to engage with the cam grooves of the first and second cam wheels. The sewing machine with a differential device according to 3 or 4 . The differential according to claim 1, 2, 3, 4 or 5 , wherein the casing is provided with a plurality of output shafts, and the phase difference generating mechanism is provided between each output shaft and the input shaft. Sewing machine with device. The sewing machine with a differential device according to claim 6 , wherein the plurality of output shafts are configured to transmit rotational outputs of different phases to the balance and the shuttle shaft. The main shaft motor for driving the main shaft and a driving unit for the needle bar are provided with another differential device for driving the needle bar driving unit at a rotational phase different from that of the main shaft motor. The sewing machine with a differential device according to 1, 2, 3, 4, 5, 6 or 7 .

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