JP2833685B2 - Sewing machine thread remover - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thread wiper (wiper).
The present invention relates to a thread removing device for a sewing machine, which is configured to perform a thread removing operation by swinging the thread.

[0002]

2. Description of the Related Art In various sewing machines, after a sewing operation is completed and a thread is trimmed, a structure in which a thread wiper is swung to perform a thread sweeping operation is often employed. The thread wiper is generally linked so as to interlock with a presser lifting mechanism for moving the presser foot up and down, and when the driving means of the presser lifting mechanism is operated, the presser foot is moved up and down. In addition, the thread wiper is configured to swing.

[0003]

However, in such a thread wiper having a structure interlocked with the conventional presser lifting mechanism, the presser lifting mechanism must always be operated when the thread wiper operation is performed. Depending on the mode, the presser foot may perform meaningless operation. And that may reduce the efficiency of sewing work,
It has traditionally been a problem.

[0004] For example, a sewing machine with a lockstitch button is used in FIG.
When sewing the four-hole button 1 as shown in FIG.
As shown in FIG. 4 (a), four holes 3, 3 and 4, 4 are continuously sewn via the transition thread 2 without thread trimming during one cycle from the start of sewing to the end of sewing. As shown in FIG. 14 (b), the sewing mode with a crossover thread and one cycle from the start of sewing to the end of sewing are halved,
Thread trimming is performed once at the end of the half-split cycle sewing on the three holes 3, 3, and then thread trimming is performed again after performing the half-split cycle sewing on the latter two holes 4, 4. There is a sewing mode without thread crossing.

However, as shown in FIG.
In the case of performing the sewing mode without the crossover thread, the conventional thread wiper performs the thread sweeping operation after the first thread trimming. The sewing operation takes time. In this case, it is conceivable to completely separate the presser lifting mechanism for moving the presser foot up and down and the operation mechanism of the thread wiper, but such a configuration leads to a complicated mechanism. In addition, when both mechanisms must be driven by a solenoid or the like at the same time, a large drive current is required, which is expensive in an electric control system.

Accordingly, the present invention provides a thread remover for a sewing machine which has a simple configuration and does not cause the presser foot to perform meaningless operations, and can efficiently execute various sewing modes. The purpose is to do.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a press-up mechanism for moving a presser foot up and down, and a press-up mechanism connected to the press-up mechanism via a predetermined link mechanism. And a thread wiper that performs a thread wiper operation, wherein the thread wiper performs a threading operation independently of the interlocking operation from the presser lifting mechanism. a drive means, a first sewing mode to operate the thread wiper strip in conjunction with the lifter mechanism, press
A second sewing mode in which the thread wiper is independently operated by the thread wiper driving means without interlocking with the lifting mechanism ;
And a mode determination control means for selecting and executing the program.

[0008]

In the apparatus having the above-described structure, when performing the thread-wiping operation after performing the thread trimming, in the case of the second sewing mode in which the raising operation of the presser foot is not required, the thread-wiping driving means is provided. In the first sewing mode , in which the thread wiper is operated separately from the operation of the presser lifting mechanism and both the thread wiper operation and the lifting operation of the work clamp are required, the operation of the presser lifting mechanism is performed. The thread wiper is operated in conjunction with the operation.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a cycle sewing machine with a lockstitch button will be described below in detail with reference to the drawings.
First, as shown in FIG. 1, a driving force from a driving motor 13 is transmitted to a sewing machine main body 12 mounted on an operation console 11. The drive motor 13 includes a servomotor or an electromotor electrically controlled by a sewing machine controller (motor sewing machine controller) 14, and the stop control is performed by a fixed number of stitches or a detection signal from a sensor. Therefore, the machine main body 12 does not include a speed increasing / decreasing device, a cutoff frame, and the like. The start and stop of the sewing machine main body 12 by the drive motor 13 are configured to be performed by a command from the foot pedal 15. Reference numeral 16 in the figure denotes a transition thread presence / absence switch for switching between the presence and absence of transition threads in a four-hole sewing mode described later.

Next, as shown in FIGS. 2 and 3, a main shaft 21 is disposed on the sewing machine main body 12 so as to extend substantially horizontally above the sewing machine. Are screwed and fixed so that the drive pulley 22 rotates integrally. The drive motor 13 described above is disposed immediately below the drive pulley 22, and the output shaft of the drive motor 13 is connected to the drive pulley 2.
2, a transmission belt 23 made of a V belt or the like is stretched.

A needle bar 25 is attached to the opposite end of the main shaft 21 via a predetermined crank transmission mechanism 24, and a sewing needle 26 attached to a lower end of the needle bar 25 is provided.
Are arranged so as to approach / separate from the rotary hook 27 disposed immediately below the needle plate. The rotary kettle 27
The driving force from the main shaft 21 is transmitted to a lower shaft 28 connected to the lower shaft 28 via a predetermined crank transmission mechanism 29.

A cam shaft 32 is disposed substantially vertically in the middle of the main shaft 21 via a worm gear mechanism 31, and a lower end of the cam shaft 32 is provided with a cloth feed cam 33.
Further, the thread trimming control cam 34 is fixed so as to be vertically overlapped. The worm gear mechanism 31 has a reduction ratio at which the cam shaft 32 makes one rotation with a predetermined number of stitches corresponding to one cycle from the start of sewing to the end of sewing.
The cloth feed cam 33 reciprocates a button and a cloth feed mechanism (described later) for gripping a workpiece in two orthogonal X and Y directions. The thread trimming mechanism described above is operated.

A thread trimming cam 35 formed in a predetermined outer peripheral shape is screwed and fixed to the main shaft 21. A thread trimming cam constituting a thread trimming control mechanism is provided near the thread trimming cam 35. An arm 36 is swingably provided on the machine frame of the sewing machine arm with a pin 37. Thread cutting cam arm 36
Are three arms 3 extending radially from the pin 37.
6A, 36B and 36C. A roller 36a is rotatably provided at the distal end of the first arm 36A that extends diagonally upward toward the thread cutting cam 35.
The roller 36 a is arranged at a position where the roller 36 a can be pressed against the cam surface of the thread cutting cam 35. On the outer peripheral surface of the thread cutting cam 35, a cam surface for performing a predetermined thread cutting operation on the thread cutting cam arm 36 is formed.

The remaining two second arm 36B and third arm 36C of the thread cutting cam arm 36 are connected to the pin 37
A roller 36b is rotatably provided at a tip of a second arm 36B extending to a position substantially directly below the thread cutting cam 35 from the left and right sides. The roller 36b is configured so that a swinging end portion of a cam arm return arm 38 described later is pressed and separated from the roller 36b. Still another third arm 36C extends rearward away from the thread cutting cam 35, and a roller 36c is rotatably provided at the tip of the third arm 36C. The upper end of the cutting connecting rod 39 is rotatably attached.

The thread cutting connecting rod 39 is connected to the thread cutting cam arm 3.
6 extends downward so as to hang downward, and the lower end thereof is rotatably connected to a thread cutting link 41 having a substantially “L” shape. The thread cutting link 41 is connected to the main shaft 2.
The thread cutting connection rod 39 is fixed to a shaft 42 rotatably supported by the machine frame so as to extend in a direction perpendicular to the direction 1 and pushes the thread cutting connecting rod 39 upward at one end of the thread cutting link 41. The tension spring 43 is stretched between the frame and the frame. The other end of the thread cutting link 41 is rotatably connected to a thread cutting connecting rod 44 extending toward a thread cutting mechanism (not shown). That is, the thread cutting operation transmitted through the thread cutting cam 35, the thread cutting cam arm 36, and the thread cutting connecting rod 39 is transmitted to the thread cutting mechanism by the thread cutting link 41.

The cam arm return arm 38 is formed of a plate member having a substantially "C" shape in front of which is swung by the thread trimming control cam 34, and the thread trimming cam arm 36 is provided on the cam surface of the thread trimming cam 35.
Are rotatably mounted by a pin 40 so as to abut and separate from each other. One end (upper end) of the cam arm return arm 38 is connected to the roller 36b of the thread trimming cam arm 36 as described above.
The cam arm return arm 38 is disposed so as to be separated from the roller 36b of the thread cutting cam arm 36 by the upward pulling force of a tension spring 45 connected to the other end of the cam arm return arm 38. It is being rushed. Also this cam arm return arm 38
The lower end of the connecting link 46 is connected to the other end (lower end) of the thread. The lower end of the connecting link 46 is pivoted by the thread cutting control arm 48B fixed to one end of the horizontal shaft 47. It is connected to the end. Further, on the other end side of the horizontal shaft 47,
The thread trimming control arm 48A is fixed.
A thread cutting control lever 51 is connected to the swinging end of 8A via a connecting link 50.

The thread trimming control lever 51 is pivotally supported by a vertical shaft 52 in a substantially horizontal plane. One end of the thread trimming control lever 51, which is formed in a substantially U-shape in a plane, is provided. The connecting link 50 on the cam arm return arm 38 side described above.
It is connected to. The roller 53 rotatably provided at the other end of the thread trimming control lever 51 is pressed against the outer peripheral cam surface of the thread trimming control cam 34 by the above-described tensioning biasing force of the tension spring 45. It is configured to:

The thread trimming control cam 34 is supported substantially horizontally, and is rotated once during one cycle of sewing operation in conjunction with the main shaft 21 as described above. The outer peripheral cam surface of the thread trimming control cam 34 has a non-operation surface 34a and a non-operation surface 34a.
And two operating surfaces 34b, 34b recessed in a part of the. Each of the operation surfaces 34b, 34b is formed to have a concave groove shape, and is disposed at a position substantially point-symmetric about the rotation shaft 32. As described later, the roller 5 of the thread trimming control lever 51 is provided in the operation surface 34b.
When the thread 3 is dropped, the roller 36a of the thread cutting cam arm 36 in the thread cutting control mechanism is pressed against the outer peripheral cam surface of the thread cutting cam 35, and the roller 53 of the thread cutting control lever 51 is controlled by the thread cutting control. When maintained on the non-operating surface 34a of the cam 34, the roller 36a of the thread cutting arm 36 is configured to be separated from the cam surface of the thread cutting cam 35.

Further, the third arm 3 of the thread trimming cam arm 36
Above 6C, a thread trimming auxiliary cam 55 constituting thread trimming inhibiting means is rotatably provided. This thread cutting auxiliary cam 5
Reference numeral 5 has a substantially fan-shaped outer peripheral cam surface, and the fan-shaped outer peripheral cam surface is configured to abut and separate from the roller 36c of the thread cutting cam arm 36. Further, from the rotation center of the thread trimming assist cam 55, the operation arm 55a is
A tension spring 56 extends in a direction away from the thread cutting cam 35 and is hooked on an intermediate portion of the operation arm 55a.
By the downward pulling force, the cam surface of the thread trimming auxiliary cam 55 is urged to be separated from the roller 36c of the thread trimming cam arm 36.

Further, an output shaft of a thread cutting inhibiting solenoid 57 as thread cutting inhibiting means is connected to the extending end of the operating arm 55a from below. The output shaft of the thread cutting prohibition solenoid 57 is connected to the thread cutting prohibition solenoid 57.
When it is turned on, it is provided so as to rotate the thread cutting auxiliary cam 55 against the urging force of the tension spring 56. By the operation of the thread trimming prohibiting solenoid 57, the cam surface of the thread trimming auxiliary cam 55 is pressed against the roller 36c of the thread trimming cam arm 36, and the roller provided on the first arm 36A of the thread trimming cam arm 36 at that time. 36a is held in a state separated from the cam surface of the thread cutting cam 35.

Next, the presser lifting mechanism and the thread removing mechanism will be described. As shown in FIG.
The presser arm 81a of the presser foot 81 which is moved up and down is attached such that a base 81b on the back side thereof can open and close and turn the presser arm 81a in the vertical direction, and the distal end of the presser arm 81a. Is provided with a pair of cloth presser feet 81c for holding the sewing object together with the feed plate 81d. The cloth presser foot 81c is configured to be vertically rotated together with the presser arm 81a. Further, on the upper surface side of the presser arm 81a of the cloth presser 81, a connecting operation plate 8 is provided.
1d is mounted so as to protrude upward, and a rotating force from a press-up mechanism 80 described below is applied to the connecting operation plate 81d as a vertical opening / closing force.

In the presser-lifting mechanism 80, a presser-lifting driving means 80a comprising a solenoid, a motor or the like is used.
Is connected to one end of a substantially L-shaped press-up lever 80d via a predetermined vertical link plate 80c, and the other end extending above the press-up lever 80d has , One end of the horizontal link plate 80e is connected. The presser lifting lever 80d is swingably held by a support shaft 80f fixed to the machine frame of the sewing machine arm, and one end of a coil spring 80g that resists the downward tension output of the presser lifting driving means 80a is hooked. By being stopped, the presser lifting lever 80d is urged so as to be jumped upward.

Further, the distal end of the horizontal link plate 80e is connected to the illustrated lower swing end of the first push-up arm 80h. The boss portion of the first push-up arm 80h is fixed to a rotation shaft 80j rotatably held on the machine frame of the sewing machine arm, and is configured to swing with the rotation of the rotation shaft 80j. I have. Further, a second push-up arm 80k is fixed to the rotation shaft 80j. A pin 80m is projected from the lower swinging end of the second push-up arm 80k in the drawing, and the pin 80m comes into contact with and engages with the edge of the connection operating plate 81d in the cloth presser 81 described above. ing. The swinging motion of the second push-up arm 80k allows the presser foot 81 to be opened upward through the connection operation plate 81d of the presser foot 81.

On the other hand, one end of an upper link 82a extending in a substantially horizontal direction so as to constitute a thread removing mechanism 82 is rotatably connected to the swinging end side of the first push-up arm 80h. The other end of the upper link 82a is connected to the first wiper arm 82
b is rotatably connected to the swing arm side. As shown in FIG. 5, the base side of the first wiper arm 82b is rotatably attached to a support shaft 82c fixed to the machine frame of the sewing machine arm. In addition, this first wiper arm 8
An upper engagement piece 82d extends substantially horizontally from the base of 2b. The upper engagement piece 82d is bent to form a key shape, and has an L-shape substantially orthogonal to the swing arm side to which the upper link 82a is connected. At this time, the swing arm side of the first wiper arm 82b is pulled in the direction of arrow B in FIG. 5 by the urging force of the coil spring 80g of the press-up mechanism 80 described above. It is pushed down in the direction of arrow C on the lower side.

Further, a base side of a second wiper arm 82e is rotatably attached to the support shaft 82c. The second wiper arm 82e is arranged in a substantially horizontal direction,
The first wiper arm 82b is disposed so as to be substantially orthogonal to the swing arm side. One end of a link plate 82f is rotatably connected to the tip of the swing arm extending rightward in FIG. 5 of the second wiper arm 82e. A lower engagement piece 82g extending in a substantially horizontal direction toward the opposite side of the swing arm of the second wiper arm 82e is disposed immediately below the upper engagement piece 82d of the first wiper arm 82b. The key-shaped tip of the upper engagement piece 82d of the first wiper arm 82b is pressed against the lower engagement piece 82g of the second wiper arm 82e from above. Therefore, the first wiper arm 82b
Of the second engaging piece 82d (arrow C).
The lower engaging piece 82g of the wiper arm 82e is also pushed down in the drawing, whereby a swinging force of the second wiper arm 82e in the direction of arrow D is applied to the swing arm.

Further, a link plate 82f connected to the swing arm side of the second wiper arm 82e extends in a substantially vertical direction, and a lower end of the link plate 82f is used as a thread wiper (wiper). It is rotatably connected to the base-side arm portion 82j at 82h. Threading piece 82h
Is a mounting plate 82k screwed to the machine frame of the sewing machine arm.
The end of a swing arm arranged so as to hang downward from the base side arm portion 82j side swings, so that a predetermined thread sweeping operation is performed. It is configured to be. As described above, the thread lifting piece 82h is attached to the presser lifting mechanism 8 described above.
A thread sweeping mechanism 82 that is linked to 0 is additionally provided.

The thread scraper 82h is provided with thread scraper driving means 83 for independently operating the thread scraper 82h independently of the operation of the presser lifting mechanism 80 described above.
The thread wiping drive means 83 includes a rotary solenoid 83
The swing arm of the drive arm 83c fixed to the rotary output shaft 83b of the rotary solenoid 83a is rotatably mounted on the middle of the swing arm of the thread wiper 82h via the link plate 83d. Are linked. That is, the threading piece 82h independently performs the threading swinging operation by the rotational drive of the rotary solenoid 83a.

Next, an example of a control system in the thread trimming control device used in the cycle sewing machine with a button having the above-described configuration will be described. The sewing machine control device (motor sewing machine controller) 14 has an arithmetic processing device (CPU) 61 as shown in FIG. 9, and a read-only memory (RO) is provided to the arithmetic processing device 61.
M) 62, a random access memory (RAM) 63, an input / output device (I / O), and the like. The motor control means 64 provided in the arithmetic processing unit 61
A detection signal from a motor speed detector (encoder) 65 attached to a motor rotation shaft is applied to the input side of the motor so as to detect the rotation speed of the sewing machine drive motor 13. The input side of the sewing machine control means 66 is provided with a detection signal from a sewing needle position detector 67 incorporated in the pulley so as to detect the position of the sewing needle 26, and a cycle origin detector 68 for notifying the timing of the start of sewing. , An operation signal from a pedal sensor 69 for notifying a command from the foot pedal 15, a setting signal from the jumper presence / absence switch 16, and the like.

The sewing machine control means 66 is provided with a mode determination means 66a for selecting a sewing mode based on the input signals described above.
Each sewing mode command such as the sewing mode with four hole jumping threads (first sewing mode) and the sewing mode without four hole jumping threads (second sewing mode) selected by
It is configured to be output to. On the other hand, the output side of the motor control means 64 is connected to the sewing machine drive motor 13 via a sewing machine motor driver circuit 71, and the output side of the sewing machine control means 66 is connected to the output side of the sewing machine through a wiper solenoid driver circuit 74. The wiper solenoid 83a is connected, and a presser foot driving means, for example, a presser foot solenoid 80a, is connected via a presser foot solenoid driver circuit 72.

In the embodiment apparatus having such a configuration, first, as shown in FIG. 10, the system is initialized immediately after the power is turned on (step 1). It is checked whether or not is turned on (step 2). Jumping thread existence switch 1
If No. 6 is in the on state (Yes), the four-hole crossover threadless sewing mode is set (step 3), and if the crossover thread presence / absence switch 16 is off (No), 4
The sewing mode without the crossover thread is cleared (step 4). At this time, it is checked whether or not the start position of the cloth feed cam 33 is at the origin of the cycle (step 5).
If it is not the cycle origin, error processing is performed (step 6). Whether or not the foot pedal 15 is depressed is checked by turning on / off the pedal sensor 69 (step 7). If the foot pedal 15 is depressed and the pedal sensor 69 is turned on, the work clamp After the sewing machine 81 is lowered (step 8), a cycle operation as described below is executed (step 9).
1 is raised again (step 10).

In the cycle operation of the step 9, as shown in FIG. 11, after the stitch number counter in the RAM 63 is cleared (step 11),
The motor rotation command is output to the motor control means 64 in the arithmetic processing unit 61 (step 12). The motor control means 64 receives the command from the sewing machine control means 66, determines the content of the command, and drives the motor driver circuit 71 so that the detection signal from the motor speed detector (encoder) 65 matches the command signal. A signal is provided.
As a result, the sewing machine drive motor 13 is rotated and the main shaft 21 is rotated.
Is rotated.

When the main shaft 21 is driven to rotate, the upper end position of the sewing needle 26 is set to 1 by the sewing machine needle position detector 67.
It is detected for each rotation (step 13), and a pulse-like needle-on signal as shown in FIGS. 12 (b) and 13 (b) is obtained. Then, each time the needle up signal from the sewing machine needle position detector 67 rises, the stitch number counter is counted up (step 14 in FIG. 11). At this time, when the sewing mode without the four-over-crossing thread is checked (step 15 in FIG. 11), it is determined that the sewing mode without the four-over-the-over-thread is not the sewing mode with four-over-the-over-thread, that is, the sewing is started. In the case of the first sewing mode in which the sewing is continuously performed without the thread trimming operation for one cycle from the first sewing to the end of the sewing (in the case of FIG. 12), first, the thread trimming prohibiting solenoid 57 is turned on in FIG.
Is maintained in a non-operating state. At the start of the operation, the roller 53 of the thread trimming control lever 51 as shown in FIG.
Is on the non-operation surface 34a of the thread trimming control cam 34, so that the cam arm returning arm 38 is moved to the thread trimming cam arm 36 as shown in FIG.
Is maintained in a position where the roller 36a of the thread cutting cam arm 36 is separated from the cam surface of the thread cutting cam 35. Therefore, thread trimming cam 3
Sewing is started without transmitting the thread cutting information from the sewing machine 5.

At a predetermined timing immediately before the end of the first half cycle, for example, when the number of stitches counter is (n / 2)
When -3 (n is the number of cycle stitches) is reached (step 16 in FIG. 11), the thread trimming inhibition solenoid 57 is switched to the operating state as shown in FIG. 8 (step 1 in FIG. 11).
7). As a result, the thread trimming auxiliary cam 55 rotates so as to be pressed against the roller 36c of the thread trimming cam arm 36, and the roller 36a of the thread trimming cam arm 36 is moved by the binding force of the thread trimming auxiliary cam 55.
The thread trimming cam 35 is held at a position separated from the cam surface. Accordingly, as shown in FIG. 7B, the roller 53 of the thread trimming control lever 51 on the non-operation surface 34a of the thread trimming control cam 34.
However, as shown in FIG. 6B, the operating surface 34 of the thread trimming control cam 34
6 (a), the cam arm return arm 38 moves from the position where the thread cutting cam arm 36 is separated from the cam surface of the thread cutting cam 35, which is the position shown in FIG. 7 (a). 8), the thread cutting cam arm 36 is moved to a position where the thread cutting cam arm 36 comes into contact with the cam surface of the thread cutting cam 35 as shown in FIG.
The roller 36a is held at a position separated from the cam surface of the thread cutting cam 35. Therefore, the sewing is continued without transmitting the thread trimming information from the thread trimming cam 35, and the thread trimming operation at the end point of the half-split cycle is avoided. At this time, press
The lifting solenoid 80a of the lifting mechanism 80 is inactive.
Linked to the presser lifting mechanism 80
The related thread wiper 82h is also kept in the inactive state.

Thereafter, at a predetermined timing, for example, when the number of stitches counter reaches (n / 2) +2 (step 18 in FIG. 11), the thread trimming inhibition solenoid 57 is again turned on as shown in FIG.
(Step 19 in FIG. 11), but at this time, the roller 5 of the thread trimming control lever 51 is turned off.
7 is pressed against the non-operation surface 34a of the thread cutting control cam 34, the cam arm returning arm 38 separates the thread cutting cam arm 36 from the cam surface of the thread cutting cam 35 as shown in FIG. It is maintained in the position to let. Accordingly, the sewing without thread trimming as shown in FIG. 12A is continued over one cycle without transmitting the thread trimming information from the thread trimming cam 35.

Then, the sewing is continued and the stitch number counter is checked (step 23 in FIG. 11). If the stitch number counter matches the cycle stitch number n, a stop command is issued to the sewing machine drive motor 13. (Step 24 in FIG. 11), the motor is stopped (see FIG. 12A). Also at this time, the thread trimming prohibiting solenoid 57 is maintained in a non-operating state, and the thread trimming assist cam 55 for the thread trimming cam arm 36 is held.
Has been released. Therefore, as shown in FIG. 7B, the thread trimming control lever 51 on the non-operation surface 34a of the thread trimming control cam 34 is moved to the thread trimming control cam 3 as shown in FIG.
4, when it moves so as to fall into the operating surface 34b,
The position shown in FIG. 6A, ie, the cam of the thread cutting cam 35, from the position where the cam arm return arm 38 separates the thread cutting cam arm 36 from the cam surface of the thread cutting cam 35, ie, the position of FIG. The thread cutting cam arm 36 moves to a position where the thread cutting cam arm 36 comes in contact with the surface, and as a result, the thread cutting cam arm 36 performs a predetermined swinging operation along the cam surface of the thread cutting cam 35, and The thread trimming operation is performed at the exit timing.

After such a thread trimming operation is performed, the presser lifting solenoid 80a is operated, and the presser foot 81 is opened upward through the presser lifting mechanism 80. In conjunction with the operation of the presser lifting mechanism 80, the thread wiper 82
h is oscillated, thereby executing the thread wiping operation after thread trimming. If the swinging of the thread scraper 82h is performed in conjunction with the presser lifting mechanism 80 as in the first sewing mode , the entire mechanism is simplified, and both operations are performed with a relatively small drive current. It has become.

On the other hand, when it is determined in step 15 in FIG. 11 that the sewing mode is "four-hole crossover thread-less sewing mode" (Yes), one cycle from the start of sewing to the end of sewing is divided in half, and At the end of the half-split cycle, thread trimming is performed and the sewing is temporarily terminated. In the second sewing mode, when the number of stitches reaches n / 2 and the sewing of two holes is completed (step 20 in FIG. 11), the sewing machine drive motor 13 is temporarily stopped. (Step 21 in FIG. 11), the sewing operation is temporarily terminated (FIG. 13 (a)).
reference). At this time, the thread cutting prohibition solenoid 57 is maintained in a non-operating state, and the restraining force of the thread cutting assist cam 55 on the thread cutting cam arm 36 is released. Accordingly, as shown in FIG. 7B, the thread trimming control lever 51 on the non-operating surface 34a of the thread trimming control cam 34 is moved into the operating surface 34b of the thread trimming control cam 34 as shown in FIG. When the cam arm return arm 38 is moved downward, the cam arm return arm 38 moves from the position shown in FIG. 7A, that is, the position where the thread cutting cam arm 36 is separated from the cam surface of the thread cutting cam 35, as shown in FIG. The thread cutting cam arm 36 is moved to the position (a), that is, a position where the thread cutting cam arm 36 comes into contact with the cam surface of the thread cutting cam 35, and as a result, the thread cutting cam arm 36 The swinging operation is performed, and the thread cutting operation is performed by the cooperation of the movable blade and the fixed blade at the timing when the needle comes off.

Then, following this thread cutting operation, the wiper solenoid 83a of the thread wiper driving means 83 is turned on (FIG. 1).
In step 22 of 1), the thread scraper 82h is swung to execute the thread scraping operation after thread trimming. At this time, the presser-lifting solenoid 80a of the presser-lifting mechanism 80 is kept in the off state, and therefore, the presser-lifting mechanism 80 is kept in the inactive state, and the cloth presser 81 is kept at the closed position. This is because the sewing of the remaining two button holes is subsequently performed, and there is no need to open the cloth presser 81 and take out the sewing object. In this way, the unnecessary lifting operation of the work clamp 81 is omitted, and the sewing operation can be performed efficiently.

Then, the sewing of the remaining two button holes is continued, the number of stitches is checked (step 23 in FIG. 11), and if the number of stitches matches the number of cycle stitches n, the sewing machine drive motor 13 Is issued (step 24 in FIG. 11), and the motor is stopped again (see FIG. 13A). At this time, the same thread trimming operation and thread wiping operation as described above are executed. That is, after the predetermined thread trimming operation is performed, when the presser lifting solenoid 80a of the presser lifting mechanism 80 is operated, and the cloth presser 81 is opened upward through the presser lifting mechanism 80, the operation of the presser lifting mechanism 80 is interlocked. Then, the thread scraper 82h is swung, and the thread scraping operation after thread trimming is executed. By swinging the thread scraper 82h in conjunction with the presser lifting mechanism 80 in this manner, the entire mechanism is simplified and a predetermined operation is performed with a relatively small drive current.

As described above, in the present embodiment, the second sewing mode
For example, in the case of finishing the sewing of two holes in the first half and performing the thread trimming operation after performing the thread trimming operation as in the "sewing mode without thread passing through four holes", the lifting operation of the presser foot 81 is performed. Is unnecessary, the wiper solenoid 83a as a thread sweeping driving means causes the thread sweeping piece 82h to perform the thread sweeping operation independently and independently of the operation of the presser lifting mechanism 80, and the thread sweeping operation and the work clamp When both the lifting operation and the lifting operation are necessary, the thread
Is made to perform a thread sweeping operation. Therefore, the lifting operation of the cloth presser 81 which is originally unnecessary is omitted, and the sewing operation is efficiently performed. At the same time, when the raising operation of the cloth presser 81 is required, the swing of the thread wiper 82h is raised. Mechanism 8
By performing the operation in conjunction with 0, the mechanism can be simplified and the driving current can be saved.

Although the invention made by the inventor has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say. For example, in the above-described embodiment, the “sewing mode without four hole jumping threads” and the “sewing mode with four hole jumping threads” are determined. However, in the present invention, the button sewing mode with various numbers of holes is determined. Is similarly possible, and the present invention is not limited to the cycle sewing machine, but is applicable to sewing machines having various configurations.

[0042]

As described above, the thread wiper of the sewing machine according to the present invention uses the thread wiper driving means in the sewing mode in which the lifting operation of the presser foot is unnecessary when performing the thread wiper operation. When the thread wiper performs the thread sweeping operation separately and independently of the operation of the presser lifting mechanism, and when both the thread sweeping operation and the lifting operation of the work clamp are necessary, the operation of the presser lifting mechanism is performed. The thread wiper is operated in conjunction with the thread wiper to perform the thread wiper operation.This eliminates the unnecessary unnecessary lifting operation of the presser foot, efficiently performing the sewing operation, and raising the presser foot. When operation is required, the thread wiper is swung in conjunction with the presser foot lifting mechanism, which simplifies the mechanism and saves drive current. Various sewing modes can be efficiently performed without performing complicated operations It can be executed.

[Brief description of the drawings]

FIG. 1 is an external perspective explanatory view showing an entire structure of a button-attached cycle sewing machine according to an embodiment of the present invention.

FIG. 2 is an explanatory perspective view of a main part showing an internal structure of the sewing machine main body shown in FIG. 1;

FIG. 3 is an explanatory diagram viewed from an arrow A showing an internal structure of the sewing machine main body shown in FIG. 2;

FIG. 4 is an explanatory perspective view of a main part showing a presser lifting mechanism and a thread removing mechanism provided in the sewing machine main body shown in FIG. 1;

FIG. 5 is an explanatory view, taken in the direction of an arrow A ′, showing an internal structure of the sewing machine main body shown in FIG. 4;

FIG. 6 is an explanatory view showing a structure of a thread cutting mechanism, and FIG.
FIG. 3 is a front view of a thread cutting cam mechanism, and FIG. 3B is a plan view of a thread cutting control cam mechanism.

FIGS. 7A and 7B are explanatory views showing a moving state of the structure of the thread cutting mechanism, wherein FIG. 7A is a front explanatory view of the thread cutting cam mechanism, and FIG. 7B is a plan explanatory view of the control cam mechanism.

FIG. 8 is an explanatory front view showing an operation state of a thread trimming prohibiting actuator with respect to a thread trimming mechanism.

FIG. 9 is a block diagram showing an example of a control system of the thread removing device of the sewing machine according to the present invention.

FIG. 10 is a flowchart showing an outline of an example of a control procedure of the thread removing device of the sewing machine according to the present invention.

FIG. 11 is a flowchart showing a cycle sewing operation in an example of a control procedure of the thread removing device of the sewing machine according to the present invention.

FIG. 12 is a timing chart showing a sewing mode with four crossover threads in an example of a control procedure of the thread removing device of the sewing machine according to the present invention.

FIG. 13 is a timing chart showing a four-crossover threadless mode in an example of a control procedure of the thread removing device of the sewing machine according to the present invention.

FIG. 14 shows four-hole buttons, and (a)
FIG. 4 is a plan view showing a sewing state in a sewing mode with four hole jumping threads, and FIG. 4B is a plan view showing a sewing state in a mode without four hole jumping threads.

[Explanation of symbols]

 13 Sewing Machine Drive Motor 14 Sewing Machine Control Device (Motor Sewing Machine Controller) 15 Foot Pedal 16 Transition Thread Presence Switch 21 Spindle 35 Thread Cutting Cam 57 Thread Cutting Prohibiting Solenoid 80 Presser Lifting Mechanism 81 Cloth Presser 82h Threader 83a Wiper Solenoid (Threading drive means)

Claims (1)

(57) [Claims] 1. A presser-lifting mechanism for moving a presser foot up and down, and a thread wiper connected to the presser-lift mechanism via a predetermined link mechanism and performing a thread-wiping operation in conjunction with the presser-lifting mechanism. A thread wiper driving means for performing a threading operation independently of the thread wiper separately from an interlocking operation from the presser lifting mechanism; and a thread wiper interlocking with the presser lifting mechanism. Actuating piece first
Mode determination control means for selecting and executing a sewing mode and a second sewing mode in which the thread wiper is independently operated by the thread wiper driving means without interlocking with the presser lifting mechanism. Sewing machine of the sewing machine.