JP3496535B2 - Link mechanism for transmitting the driving force of the sewing machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force transmission link mechanism for a sewing machine, and more particularly, to a shaft member to which a link member is fixed, and a connecting pin member for connecting the link member and the connecting rod so as to be relatively rotatable. The present invention relates to a driving force transmitting link mechanism in which the lever length between the two is adjustable by rotating the adjusting member to move the connecting pin member.

[0002]

2. Description of the Related Art Conventionally, as a drive mechanism provided in a sewing machine, a needle bar feed drive mechanism (needle bar front-back swing mechanism) that drives (swings) a needle bar back and forth, and a needle bar swings left and right. There is a needle bar left and right swing mechanism, a needle bar up and down drive mechanism that drives the needle bar up and down, a feed dog feed drive mechanism that feeds the feed dog forward and backward, and the like.The drive mechanism driven by the sewing machine motor includes: In many cases, a driving force transmission link mechanism is provided in order to transmit the driving force to the driving portion (needle bar, feed dog, etc.).

Generally, a driving force transmitting link mechanism such as a needle bar front-back swing mechanism has a link member fixed to a shaft member capable of reciprocating rotation, and one end of the link member is rotatable relative to a tip end portion of the link member. The connecting rod is connected, and when the link member is reciprocally rotated together with the shaft member, the connecting rod is swung and the driving force is transmitted. When the cloth to be sewn is a thick cloth or a plurality of superposed cloths, the needle bar back-and-forth swinging mechanism allows the cloth to be fed in order to ensure the feeding of the cloth. It is a mechanism for sending.

In the needle bar back-and-forth swinging mechanism that the applicant of the present invention has put into practical use, the shaft member (horizontal feed shaft) is arranged in the bed portion, and the other end portion (upper end portion) of the connecting rod is the arm portion. When the horizontal feed shaft is reciprocally rotated in conjunction with the main shaft that is rotationally driven by the sewing machine motor, the horizontal feed shaft is rotatably connected to the distal end of the needle feed link member that is fixed to the needle feed shaft that is arranged in The connecting rod is oscillated, the needle feed shaft is reciprocally rotated together with the needle feed link member, and the needle bar is oscillated back and forth together with the needle bar base.

By the way, when it is desired to adjust the drive amount (oscillation amount, feed amount, etc.) of the drive portion (needle bar, feed dog, etc.) of the drive mechanism, the adjustment is performed by lever length between the shaft member and the connecting pin member ( That is, the link mechanism for driving force transmission, which can be performed by adjusting the swing amount of the connecting rod, has been put to practical use. In this type of link mechanism, a long hole is formed in the lever portion of the link member,
A pivot hole corresponding to the elongated hole is formed at one end of the connecting rod, and the link member and the connecting rod are rotatably connected to each other by a connecting pin member inserted into the elongated hole and the pivot hole. .

The connecting pin member is, for example, a stepped screw, and the pin portion of the connecting pin member is inserted into the pivotal support hole of the connecting rod.
The connecting pin member is releasably fixed to the link member by the nut member screwed to the step portion and the screw portion of the connecting pin member. Then, the nut member is loosened to release the fixing of the connecting pin member to the link member, and the operator directly moves the connecting pin member along the long hole of the link member, so that between the shaft member and the connecting pin member. The lever length (the amount of swing of the connecting rod) can be adjusted.

[0007]

In the conventional drive force transmitting link mechanism, when adjusting the lever length between the shaft member and the connecting pin member, the operator directly holds the connecting rod or the like by hand and connects the connecting pin. The member must be moved along the elongated hole of the link member, and at this time, since the connecting pin member is inserted into the elongated hole in a fitting manner, the link member is connected to both ends of the connecting rod. When the connection pin member is rotated, it is difficult to smoothly move the connecting pin member along the long hole.

Further, when the connecting rod swings and the connecting pin member is easy to move after adjusting the lever length, the operator holds the connecting rod or the like by hand to hold the adjusted state, and Since it is necessary to tighten the member and fix the connecting pin member to the link member, the work of adjusting the lever length becomes very difficult. As described above, the conventional driving force transmitting link mechanism has a problem that the work of adjusting the lever length cannot be easily performed.

In addition, when adjusting the drive amount (oscillation amount, feed amount, etc.) of the drive unit (needle bar, feed dog, etc.), the operator has to make a connecting pin member for the long hole because the size of the slot is relatively short. There is a problem that it is very difficult to accurately adjust the drive amount (lever length) to be adjusted even if the lever length is sensuously adjusted by observing the position. An object of the present invention is to facilitate the work of adjusting the lever length between the shaft member and the connecting pin member, and also to drive the driving portion (lever length) desired to be adjusted.
A link mechanism for driving force transmission of a sewing machine that can be accurately adjusted.

[0010]

According to a first aspect of the present invention, there is provided a link mechanism for driving force transmission of a sewing machine, the link member having a lever portion fixed to a shaft member of the sewing machine capable of reciprocating rotation, and having a lever portion. Drive having a connecting rod having a pivot hole corresponding to the long hole formed at one end, and a connecting pin member inserted into the long hole and the pivot hole and connecting the link member and the connecting rod relatively rotatably In the force-transmitting link mechanism, the connecting pin member is rotatably supported by the shaft member and is rotated to move the connecting pin member along the elongated hole of the link member. And a fixing mechanism for fixing the link member and the adjusting member in a releasable manner.

The driving force transmitting link mechanism is a needle bar front-back swing mechanism that drives the needle bar to swing (feed) back and forth driven by a sewing machine motor, and a left and right needle bar that swings the needle bar left and right. Swing mechanism, needle bar vertical drive mechanism for vertically driving the needle bar,
The present invention can be applied to various drive mechanisms such as a feed dog feed drive mechanism that drives the feed dog forward and backward. By fixing the link member and the adjusting member with the fixing mechanism, the position of the connecting pin member can be fixed with respect to the long hole of the link member. In this state, the link member (and the adjusting member) is When reciprocally rotated (when the connecting rod is swung), the connecting rod is swung (the shaft member is reciprocally rotated together with the link member), and the driving force is transmitted.

When adjusting the lever length between the shaft member and the connecting pin member, the fixing of the link member and the adjusting member by the fixing mechanism is released, and the connecting pin member can be moved along the elongated hole of the link member. In this state, the adjusting member pivotally supported by the shaft member is rotated. Then, the rotating adjusting member moves the connecting pin member along the elongated hole of the link member, and the lever length (the swing amount of the connecting rod) is adjusted. That is, the drive amount (oscillation amount, feed amount, etc.) of the drive unit (needle bar, feed dog, etc.) of the drive mechanism is adjusted.

According to this driving force transmitting link mechanism, the connecting pin member can be easily moved along the elongated hole of the link member by rotating the adjusting member. Even when the link members are connected to both ends, the connection pin members can be moved smoothly even when the link members are rotated. After adjusting the lever length,
Even when the connecting rod swings and the connecting pin member easily moves, the adjusted state can be easily held by not rotating the adjusting member, and in this state, the link member and the adjusting member are fixed by the fixing mechanism. And can be easily fixed, and as a result, the work of adjusting the lever length can be easily performed.

According to a second aspect of the present invention, there is provided a driving force transmitting link mechanism according to the first aspect of the invention, in which the reciprocal rotation of the horizontal feed shaft driven by the sewing machine motor is converted into a longitudinal movement of the needle bar. It is characterized in that it is provided in the swing mechanism. Therefore, the adjustment work for adjusting the back-and-forth swing amount of the needle bar driven by the needle-bar back-and-forth swing mechanism can be easily performed by rotating the adjustment member. In addition, the same operation as in claim 1 is achieved.

According to a third aspect of the present invention, in the link mechanism for driving force transmission of a sewing machine according to the first or second aspect, the adjusting member has a curved elongated hole into which a connecting pin member is inserted and is slidably guided. It is characterized by having. Therefore, by rotating the adjusting member, the connecting pin member can be guided by the elongated hole of the adjusting member and reliably and smoothly moved along the elongated hole of the link member.

Further, in the long hole of the slot and the adjusting member of the link member, a direction of each guide the coupling pin member portion connecting pin member is in contact is not related engages the relative position of the link member and the adjustment member It will always cross, so
When the link member and the adjusting member are fixed, the connecting pin member can be locked and securely fixed.

A link mechanism for driving force transmission of a sewing machine according to a fourth aspect is the link mechanism according to the third aspect, wherein the connecting pin member is
A first pin portion that is inserted into the pivotal hole of the connecting rod, and a second pin that is smaller in diameter than the first pin portion and that is inserted into the long hole of the link member and the long hole of the adjusting member and that has a threaded portion formed at the tip portion. The fixing mechanism is characterized in that the link member and the adjusting member are sandwiched by a nut member screwed to the stepped portion of the first pin portion and the screw portion of the second pin portion. .

That is, by the nut member screwed to the stepped portion of the first pin portion and the screw portion of the second pin portion of the connecting pin member,
The link member and the adjusting member can be securely sandwiched and fixed in a releasable manner, whereby the connecting pin member can be releasably fixed in (the elongated hole of) the link member, and the connection can be made. Even when the pin member is fixed to the link member, the link member and the connecting rod can be relatively rotatably connected to each other.

According to a fifth aspect of the present invention, there is provided a driving force transmission link mechanism according to any one of the first to fourth aspects, wherein the adjusting member is instructed by an instruction portion formed on the link member. It is characterized in that an indicator scale for indicating a relative rotational position between the link member and the adjusting member is provided.

The relative rotational position between the link member and the adjusting member can be indicated by the indication scale of the adjusting member indicated by the indicating portion of the link member. When the adjusting member is rotated, the relative rotational position between the link member and the adjusting member changes,
Depending on the relative rotational position, the lever length changes and the drive amount (oscillation amount or feed amount) of the drive unit (needle bar, feed dog, etc.) changes, but the relative rotational position with respect to the drive amount of the drive unit changes. By recognizing it, it becomes possible to accurately adjust the drive amount ( lever length) of the drive unit to be adjusted.

[0021]

[0022]

[0023]

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The present embodiment applies the present invention to a driving force transmission link mechanism provided in a needle bar longitudinal swing mechanism that converts the reciprocal rotation of a horizontal feed shaft driven by a sewing machine motor into the longitudinal swing of a needle bar. This is an example of the case.

As shown in FIG. 1, the sewing machine M includes a bed portion 1, a pedestal portion 2 erected on the right end portion of the bed portion 1,
It has an arm portion 3 that extends leftward from the upper end portion of the pedestal portion 2 so as to face the bed portion 1 and a head portion 4 provided at the left end portion of the arm portion 3, and the head portion 4 includes a pivot member. 5a is provided with a needle bar base 5 pivotally supported so as to be swingable back and forth.
A needle bar 6 having a sewing needle 6a attached to its lower end is supported so as to be vertically movable.

A left-right direction main shaft 7 is rotatably arranged on the arm part 3, and a left-right direction horizontal feed shaft 8 (corresponding to a shaft member) is rotatably arranged on the bed part 1. When the main shaft 7 is rotationally driven by a sewing machine motor (not shown),
The horizontal feed shaft 8 is reciprocally rotated in conjunction with the main shaft 7 by an operating mechanism (not shown) including a cam mechanism and the like. A needle bar vertical drive mechanism 15 that has a needle bar crank 16, a crank arm 17, and the like and that reciprocally drives the needle bar 6 up and down in conjunction with the main shaft 7 is provided near the head 4.

The needle bar back-and-forth swing mechanism 9 is a mechanism for converting the reciprocating rotation of the horizontal feed shaft 8 into the back-and-forth swing of the needle bar 6 (needle bar base 5). Of the driving force transmission link mechanism 10 (hereinafter referred to as the link mechanism), the needle feed shaft 11 and the needle feed shaft 11 which are arranged in the left-right direction on the rear side of the main shaft 7 in the arm portion 3. It comprises a needle feed arm 12 provided at the left end, a needle feed link 13 for operatively connecting the needle feed arm 12 and the needle bar base 5, and the like.
The reciprocal rotation of the horizontal feed shaft 8 is converted into the reciprocal rotation of the needle feed shaft 11 by the link mechanism 10, and when the needle feed shaft 11 is reciprocally rotated, the needle feed arm 12 and the needle feed link 13 are used. The needle bar base 5 pivotally supported by the pivot member 5a is swung back and forth together with the needle bar 6.

The link mechanism 10 will be described in detail. As shown in FIGS. 1 to 5, the link mechanism 10 is provided on the right side of the link member 20 and a link member 20 having a lever portion 21 externally fitted and fixed to the horizontal feed shaft 8 and having a long hole 22 formed therein. A link rod 25 having a pivot hole 26 corresponding to the elongated hole 22 formed at the lower end portion is inserted into the elongated hole 22 and the pivot hole 26, and the link member 20 and the link rod 25 are rotatably connected to each other. A connection pin member 30 and a link member 35, which is externally fitted and fixed to the needle feed shaft 11 and whose tip portion is rotatably connected to the upper end portion of the connecting rod 25, are provided.

Further, the link mechanism 10 includes a link member 20.
Is rotatably supported on the horizontal feed shaft 8 on the left side of the link pin 2 by rotating the horizontal feed shaft 8.
The adjusting member 40 that can be moved along the long hole 22 of 0 to adjust the lever length (the swing amount of the connecting rod 25) between the horizontal feed shaft 8 and the connecting pin member 30, the link member 20, and the adjusting member 4.
The fixing mechanism 45 (refer to FIG. 4) for fixing 0 and 0 in a releasable manner is provided.

The link member 20 has a base end portion which is externally fitted and fixed to the horizontal feed shaft 8 so as to extend in a direction orthogonal to the horizontal feed shaft 8 in a block shape, and an elongated hole 22 formed in the link member 20. Is a long hole extending linearly in the direction orthogonal to the axis from the substantially central portion of the link member 20 to the vicinity of the tip. The lower end of the connecting rod 25 is the link member 2
It is arranged in the up-down direction so as to be in contact with the right surface of 0.

The connecting pin member 30 is a pivotal support hole 2 of the connecting rod 25.
6, a head portion 31 having a diameter larger than 6, a short first pin portion 32 that is inserted into the pivot hole 26 of the connecting rod 25, and a long hole 22 of the link member 20 having a diameter smaller than the first pin portion 32. The second pin portion 33 is configured as a stepped screw in which a long second pin portion 33 that is inserted into the long hole 42 of the member 40 is integrally formed in series.
A threaded portion 34 to which the nut member 46 of the fixing mechanism 45 is screwed is formed at the tip of the.

The adjusting member 40 is pivotally supported on the horizontal feed shaft 8 so as to be in contact with the left surface of the link member 20 in an externally fitted manner, and the arc outer peripheral surface 4 of about 40 degrees centering on the horizontal feed shaft 8 in a side view.
1 is formed in a substantially fan shape, and is formed from the substantially central portion to the vicinity of the end portion in the clockwise direction in a right side view of the arc outer peripheral portion 41, and the second pin portion 33 of the connecting pin member 30 is inserted therethrough. It has a curved long hole 42 which is slidably guided.

Here, with respect to the horizontal feed shaft 8, the long hole 22
And the maximum distance to the long hole 22 is set to be substantially the same as the maximum distance to the long hole 42. Furthermore, the minimum distance to the long hole 42 is set to be substantially the same as the maximum distance to the long hole 42. In the above, the direction in which the connecting pin member 30 contacts the connecting pin member 30 always intersects regardless of the relative position of the link member 20 and the adjusting member 40.

As shown in FIG. 4, the fixing mechanism 45 includes a step portion 32a of the first pin portion 32 of the connecting pin member 30, a second pin portion 33, and a second pin projecting to the left of the adjusting member 40. It has a threaded portion 34 of the portion 33 and a nut member 46 to be screwed into the threaded portion 34. When the nut member 46 is tightened, the nut member 46 and the step portion 32 a form the link member 20 and the adjustment member 4.
When 0 is sandwiched and fixed, and the nut member 46 is loosened,
The link member 20 and the adjusting member 40 are configured to be unlocked.

By fixing the link member 20 and the adjusting member 40 with the fixing mechanism 45, the position of the connecting pin member 30 can be fixed with respect to the long hole 22 of the link member 20, and in this state, the horizontal feed is performed. When the link member 20 (and the adjusting member 40) is reciprocally rotated together with the shaft 8, the connecting rod 2
5, the needle feed shaft 11 is reciprocally rotated together with the link member 35 connected to the upper end of the connecting rod 25.

When adjusting the lever length between the horizontal feed shaft 8 and the connecting pin member 30, the fixing of the link member 20 and the adjusting member 40 by the fixing mechanism 45 is performed, and the connecting pin member 30 of the link member 20 is released. The adjustment member 40, which is rotatably supported by the horizontal feed shaft 8, is rotated so as to be movable along the long hole 22. Then, the rotating adjustment member 40
However, the long hole 42 guides the connecting pin member 30 to move it along the long hole 22 of the link member 20, and the lever length (the swing amount of the connecting rod 25) is adjusted. That is, the back-and-forth swing amount of the needle bar 6 driven by the needle-bar back-and-forth swing mechanism 9 is adjusted.

When the adjusting member 40 is rotated in the direction of arrow a, the second pin portion 33 is formed on the inner end surface of the elongated hole 42 of the adjusting member 40.
Is pushed, the connecting pin member 30 moves forward along the elongated hole 22 of the link member 20, the lever length (the amount of forward and backward swing of the needle bar 6) increases, and the adjusting member 40 moves in the direction opposite to the arrow a. When it is rotated to, the second pin portion 33 is pushed by the inner end surface of the elongated hole 42 of the adjusting member 40, the connecting pin member 30 moves rearward along the elongated hole 22 of the link member 20, and the lever length is increased. (Forward and backward swinging amount of the needle bar 6) becomes small.

As shown in FIG. 3, the adjusting member 40 is moved to the arrow a.
When it is rotated to the maximum in the opposite direction, the connecting pin member 30
The second pin portion 33 of the link member 20 and the adjusting member 40.
Engaging with the inner ends of the long holes 22 and 42 of the
1, and as shown in FIG. 5, when the adjusting member 40 is rotated to the maximum in the direction of arrow a, the second pin portion 33 of the connecting pin member 30 causes the link member 20 and the adjusting member 40 to move, as shown in FIG. It engages with the inner ends of the long holes 22 and 42 of the member 40, and the lever length becomes L2 (> L1). That is, the lever length can be adjusted between L1 and L2.

By the way, a pointing portion 50 which is a notch groove is formed on the tip end surface of the link member 20, and the circular arc outer peripheral surface 41 of the adjusting member 40 is pointed by the pointing portion 50 of the link member 20. Three indicating scales 51a to 51c indicating the relative rotational positions of the link member 20 and the adjusting member 40.
However, for example, black paint is attached. When the adjusting member 40 is rotated, the relative rotational position between the link member 20 and the adjusting member 40 changes, and the lever length changes according to the relative rotational position, which changes the back-and-forth swing amount of the needle bar 6. By recognizing the back-and-forth swing amount of the needle bar 6 with respect to the relative rotational position, it becomes possible to accurately adjust the back-and-forth swing amount of the needle bar 6 to be adjusted.

In the case of the present embodiment, the lever length becomes L1 when the link member 20 and the adjusting member 40 are in the relative rotational position when the instruction section 50 indicates the instruction scale 51a (see FIGS. 2 and 3). The front-back swing amount of the needle bar 6 is the reference swing amount of the needle bar 6 and the relative rotation position of the link member 20 and the adjusting member 40 when the indicating unit 50 indicates the indication scale 51b (not shown). Swing amount is 110% of the standard swing amount
When the pointing unit 50 points the pointing scale 51c (see FIG. 5), when the link member 20 and the adjusting member 40 are in the relative rotational position, the lever length becomes L2, and the back-and-forth swing amount of the needle bar 6 becomes It is 120% of the standard swing amount.

According to this link mechanism 10, the adjusting member 4
By rotating 0, the connecting pin member 30 can be easily moved along the long hole 22 of the link member 20, and at this time, the link members 20, 3 are attached to both ends of the connecting rod 25.
Although 5 is connected, they are rotated, but the connecting pin member 30 can be moved smoothly.

Further, even after the lever length is adjusted, even if the connecting rod 25 is swung and the connecting pin member 30 is likely to move, the adjustment member 40 is not rotated so that the adjusted state can be easily maintained. In this state, the linking member 20 and the adjusting member 40 can be easily fixed by the fixing mechanism 45, and as a result, the work of adjusting the lever length can be easily performed. That is, it is possible to easily perform the adjustment work for adjusting the back-and-forth swing amount of the needle bar 6 driven by the needle-bar back-and-forth swing mechanism 9.

The adjusting member 40 has a curved elongated hole 42 into which the connecting pin member 30 is inserted and is slidably guided. Therefore, by rotating the adjusting member 40, the connecting pin member 30 is adjusted. The long hole 42 of the guide member 40 can be used to guide and smoothly and smoothly move along the long hole 22 of the link member 20.

The long hole 22 of the link member 20 and the adjusting member 40
In the elongated hole 42, the directions in which the connecting pin members 30 contact the connecting pin members 30 are always intersected with the relative positions of the link member 20 and the adjusting member 40 regardless of the position, Therefore, when the link member 20 and the adjusting member 40 are fixed, the connecting pin member 30 can be locked and reliably fixed.

The connecting pin member 30 is a pivotal support hole 2 of the connecting rod 25.
6 and the elongated holes 22 and 4 of the link member 20 and the adjusting member 40 having a diameter smaller than that of the first pin portion 32.
2 which is inserted in 2 and has a threaded portion 34 formed at the tip
Since the fixing mechanism 45 has the pin portion 33 and the link member 20 and the adjusting member 40 are sandwiched by the nut member 46 screwed to the step portion 32a of the first pin portion 32 and the screw portion 34, the link member 20 is fixed. The adjustment member 40 and the adjustment member 40 can be reliably fixed to each other so that the connection pin member 30 can be fixed to (the long hole 22 of) the link member 20 in a non-fixable manner. Link member 2 to member 30
Even in the state of being fixed to 0, the link member 20 and the connecting rod 25 can be connected so as to be relatively rotatable.

When the adjusting member 40 is instructed by the instructing portion 50 formed on the link member 20, the link member 20
Since the indicator scales 51a to 51c for instructing the relative rotation positions of the adjustment member 40 and the adjustment member 40 are provided, when the adjustment member 40 is rotated, the relative rotation positions of the link member 20 and the adjustment member 40 change, and the relative rotation thereof. Depending on the position, the lever length changes and the back-and-forth swing amount of the needle bar 6 changes, but the relative rotational position with respect to the back-and-forth swing amount of the needle bar 6 is indicated by the instruction scale 51.
By recognizing the symbols a to 51c, it becomes possible to accurately adjust the longitudinal swing amount of the needle bar 6 to be adjusted. still,
The indicating section 50 and the indicating scales 51a to 51c constitute the displaying means of claim 6.

The driving force transmitting link mechanism 10 of the above embodiment is applied to the needle bar front-back swing mechanism 9, but in addition, the needle bar left-right swing mechanism for swinging the needle bar left and right. The present invention can be applied to various drive mechanisms such as a needle bar up-and-down drive mechanism that drives the needle bar up and down, and a feed dog feed drive mechanism that drives the feed dog forward and backward. The link mechanism for driving force transmission of the sewing machine of the above embodiment is merely an example, and various modifications are added without departing from the scope of the present invention.
It goes without saying that the present invention can be applied to the driving force transmission link mechanism of various sewing machines.

[0048]

According to the driving force transmitting link mechanism of the sewing machine of claim 1, the connecting pin member can be easily moved along the elongated hole of the link member by rotating the adjusting member. At this time, the connecting pin member can be moved smoothly even when the link members are connected to both ends of the connecting rod even when the link members are rotated. Further, even if the connecting rod swings and the connecting pin member easily moves after adjusting the lever length, it is possible to easily maintain the adjusted state by not rotating the adjusting member. Thus, the link member and the adjusting member can be easily fixed by the fixing mechanism, and as a result, the work of adjusting the lever length can be easily performed.

According to the driving force transmitting link mechanism of the second aspect of the present invention, the same effect as that of the first aspect is obtained, but the reciprocating rotation of the horizontal feed shaft driven by the sewing machine motor causes the needle bar to swing back and forth. Since it is provided in the needle bar back-and-forth swing mechanism for converting to, the adjustment work for adjusting the back-and-forth swing amount of the needle bar driven by the needle bar back-and-forth swing mechanism can be easily performed by rotating the adjusting member. You can

According to the driving force transmitting link mechanism of the sewing machine of the third aspect, the same effect as that of the first or second aspect can be obtained.
Since the adjusting member has a curved elongated hole through which the connecting pin member is inserted and is slidably guided, the connecting pin member is guided by the elongated hole of the adjusting member by rotating the adjusting member to form a link. A direction in which the connecting pin member can be reliably and smoothly moved along the elongated hole of the member and guides the connecting pin member in the portion where the connecting pin member is in contact with the elongated hole of the link member and the adjusting member. However, the relative position of the link member and the adjusting member always intersects regardless of the position. Therefore, when the link member and the adjusting member are fixed, the connecting pin member can be locked and securely fixed.

According to the driving force transmission link mechanism of the fourth aspect of the present invention, the same effect as in the third aspect is obtained, but the connecting pin member includes the first pin portion which is inserted into the pivotal support hole of the connecting rod, First
The fixing mechanism has a second pin portion that has a diameter smaller than that of the pin portion and that is inserted into the long hole of the link member and the long hole of the adjusting member and has a screw portion formed at the tip portion. Since the link member and the adjusting member are sandwiched by the nut member screwed to the threaded portion of the second pin portion, the link member and the adjusting member can be reliably fixedly released so that the connecting pin can be released. The member can be releasably fixed to the link member (the long hole thereof), and even when the connecting pin member is fixed to the link member, the link member and the connecting rod can be connected relatively rotatably. it can.

According to the driving force transmitting link mechanism of the sewing machine of the fifth aspect, the same effect as that of any one of the first to fourth aspects can be obtained, but the adjusting member has the pointing portion formed on the link member. By giving an instruction scale that indicates the relative rotational position of the link member and the adjusting member by instructing, when the adjusting member is rotated, the relative rotational position of the link member and the adjusting member changes, and the relative rotation Depending on the position, the lever length changes and the drive amount (oscillation amount and feed amount) of the drive unit (needle bar, feed dog, etc.) changes, but by recognizing the relative rotational position with respect to the drive amount of the drive unit. By setting it, it becomes possible to accurately adjust the drive amount (lever length) of the drive unit to be adjusted.
Further, it is possible to easily recognize which position the current adjustment position is.

[0053]

[Brief description of drawings]

FIG. 1 is a perspective view of the inside of a sewing machine including a link mechanism according to an embodiment of the present invention.

FIG. 2 The link mechanism (state adjusted to the minimum swing amount)
FIG.

FIG. 3 is a right side view of the link mechanism of FIG.

4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a right side view of the link mechanism (state adjusted to the maximum swing amount).

[Explanation of symbols]

M sewing machine 6 needle bars 8 Horizontal feed axis 9 Needle bar front-back swing mechanism 10 Drive force transmission link mechanism 20 Link member 21 Lever part 22 long hole 25 consecutive rods 26 Pivot 30 Connection pin member 32 1st pin part 33 Second pin part 34 screw part 40 Adjustment member 42 long hole 45 fixing mechanism 46 Nut member 50 Indicator 51a to 51c Indicator scale

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) D05B 1/00-97/12

Claims (5)

(57) [Claims] 1. A link member having a lever portion fixed to a reciprocally rotatable shaft member of a sewing machine and having a long hole formed therein, and a connecting rod having a pivot hole corresponding to the long hole formed at one end. ,
In a driving force transmitting link mechanism having a connecting pin member that is inserted into the long hole and the pivotally supporting hole and relatively rotatably connects the link member and the connecting rod, the driving force transmitting link mechanism is rotatably supported by the shaft member. By rotating the connecting pin member to move along the elongated hole of the link member, an adjusting member capable of adjusting the lever length between the shaft member and the connecting pin member, and the link member and the adjusting member are provided. A link mechanism for driving force transmission of a sewing machine, comprising: a fixing mechanism for fixing the lock so that it can be released. 2. The sewing machine according to claim 1, wherein the sewing machine is provided with a needle bar back-and-forth rocking mechanism for converting reciprocal rotation of a horizontal feed shaft driven by a sewing machine motor into a back-and-forth rocking of the needle bar. Link mechanism for driving force transmission. 3. The link for driving force transmission of a sewing machine according to claim 1, wherein the adjusting member has a curved elongated hole into which a connecting pin member is inserted and which is slidably guided. mechanism. 4. The connecting pin member has a first pin portion that is inserted into a pivotal support hole of the connecting rod, and a tip that is smaller than the first pin portion and that is inserted into the long hole of the link member and the long hole of the adjusting member. A second pin portion having a screw portion formed on the portion, and the fixing mechanism includes the first pin portion.
The link mechanism for driving force transmission of a sewing machine according to claim 3, wherein the link member and the adjusting member are sandwiched by a nut member screwed to the stepped portion of the pin portion and the screw portion of the second pin portion. 5. The adjusting member is provided with an instruction scale for indicating a relative rotational position between the link member and the adjusting member by giving an instruction with an instruction portion formed on the link member. The link mechanism for driving force transmission of the sewing machine according to any one of 1 to 4.