JP2001321588A - Drive device for sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive device for a sewing machine, which can change only timing of feeding as timing of the needle and the shuttle is fixed. SOLUTION: This drive device for a sewing machine is equipped with an upper shaft 2 rotated by a motor to vertically move the needlebar, a vertical feeding shaft 4 to give the feed dog movement in the vertical direction, a horizontal feeding shaft 6 to give the feed dog movement in the horizontal direction, a first connecting members 28, 32 to connect the vertical feeding shaft 4 and the horizontal feeding shaft 6, a shuttle shaft 8 to be synchronized with the needle bar to rotate the shuttle, and transmitting means 14, 16 50, 60 with transmitting members 50, 52, 60 equipped on the vertical shaft to transmit the rotation of the upper shaft to the vertical shaft, second connecting members 34, 38, 64 to connect the transmitting members to the shuttle shaft, and coupling members 56, 62 to enable the transmitting members and the vertical shaft to be connected with or cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a driving device for a sewing machine.

[0002]

2. Description of the Related Art FIG. 5 is a view of a conventional feed driving device for a sewing machine viewed from the bottom side of the sewing machine. The upper shaft 2 is rotated by the drive of a sewing machine motor (not shown) to move the needle bar up and down via a drive mechanism (not shown). Reference numeral 4 denotes an up-down feed shaft which applies a vertical movement to a feed dog (not shown). Reference numeral 6 denotes a horizontal feed shaft for imparting a horizontal movement to the feed dog. Reference numeral 8 denotes a shuttle shaft, which rotates a shuttle (not shown) in synchronization with the needle bar.

[0003] Sprockets 14, 16 are fixed to the upper shaft 2 and the upper and lower feed shafts 4 by set screws 10, 12, respectively.
The rotation of the upper shaft 2 is transmitted to the vertical feed shaft 4 via a timing belt 18 meshing with these two sprockets. The vertical feed shaft 4 includes a bearing 2 mounted on a frame 20.
2 rotatably supported.

[0004] A horizontal feed cam 24 is fixed to the vertical feed shaft 4 by a set screw 26, and a vertical feed cam is fixed by a set screw to a distal end (not shown) (not shown). The horizontal feed cam 24 drives the horizontal feed shaft 6 via a rod 28, a feed adjuster 30, and a feed arm 32. A gear 34 is fixed to the vertical feed shaft 4 by a set screw 36, and the shuttle shaft 8 is rotated by a gear 38 meshing with the gear 34. A thread trimmer cam and a shuttle (not shown) are fixed to the shuttle shaft 8 with set screws.

With the above construction, the rotation of the upper shaft 2 is transmitted to the needle bar (not shown), the vertical feed shaft 4, the horizontal feed shaft 6, and the shuttle shaft 8, respectively.

Since the gears 34 and 38, the horizontal feed cam 24, the feed adjuster 30, and the like all have sliding parts that move at high speed, they need to be lubricated. Therefore, a closed space 40 surrounded by the frames 20, 20A, 20B and a bottom cover (not shown) is formed, and each component and lubricating oil are accommodated in the closed space 40.

[0007]

As is well known, in a sewing machine, a shuttle, a feeder and a thread trimming cam are configured to move at a predetermined timing based on the movement of a needle. . However, when the sewing conditions change, only the timing of the feed movement with respect to the movement of the needle is sometimes changed. At this time, it is almost always better not to change the timing of the shuttle and the thread trimming cam with respect to the needle. is there.
However, in the configuration of the conventional driving device, the feed timing is changed by loosening the set screw 12 of the sprocket 16 and shifting the relative position between the vertical feed shaft 4 and the sprocket 16. The timing of the shuttle shaft 8 connected to the shaft 4 is also shifted at the same time. For this reason, it is necessary to readjust the timing of the shuttle and the thread cutting cam fixed to the shuttle shaft 8 to the original state.

As another method of shifting the feed timing with respect to the needle, the set screw 26 of the horizontal feed cam 24 and the set screw of the vertical feed cam (not shown) can be loosened and shifted. It is necessary to make the shift amount the same, it is troublesome, and the horizontal feed cam 2
Since 4 is housed in the closed space 40 for lubrication, it is necessary to remove the bottom cover in order to loosen the set screw 26, and the timing cannot be easily shifted.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a drive device for a sewing machine which can change only the timing of feeding while keeping the timing of the needle and the shuttle constant.

[0010]

According to the present invention, there is provided, in accordance with the present invention, an upper shaft which rotates by driving a sewing machine motor to vertically move a needle bar, and imparts a vertical movement to a feed dog. A vertical feed shaft, a horizontal feed shaft for imparting horizontal movement to the feed dog, first connecting means for connecting the vertical feed shaft and the horizontal feed shaft, and a shuttle shaft for rotating the shuttle in synchronization with the needle bar A transmission means for transmitting the rotation of the upper shaft to the vertical feed shaft, a second connecting means for connecting the transmission member to the shuttle shaft, A driving member for the sewing machine, comprising: a coupling member capable of connecting or disconnecting the upper and lower feed shafts.

For example, the transmission means has a hollow shaft capable of loosely fitting a vertical feed shaft on an inner peripheral portion thereof and connecting the shuttle shaft to an outer peripheral portion, one end of which is fixed to the hollow shaft, and the other end of which has the above-mentioned end portion. And a sprocket that is linked to the vertical feed shaft by a coupling member.

[0012] Alternatively, the transmission means may include a hollow shaft capable of inserting a vertical feed shaft into an inner peripheral portion thereof and connecting the shuttle shaft to an outer peripheral portion, one end of which is integrally connected to the hollow shaft, And a sprocket connected to the vertical feed shaft by the coupling member. Preferably,
The coupling member is disposed outside the sealed lubrication chamber.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a sewing machine driving device according to the present invention will be described with reference to FIGS. This drive device is different from the drive device of the conventional sewing machine in that the shape of a sprocket 50 constituting a transmission member attached to the vertical feed shaft 4 and a transmission means between the sprocket 50 and the vertical feed shaft 4 are provided. The difference is that the hollow shaft 52 is provided and the arrangement of gears (second connecting means) 34 and 38 for connecting the vertical feed shaft 4 and the shuttle shaft 8 is different.

First, the parts denoted by the same reference numerals as those in FIG. 5 are the same or equivalent parts as those in the conventional example. Therefore, in brief, the upper shaft 2 is provided with a needle bar driven by a sewing machine motor (not shown). Move up and down. The vertical feed shaft 4 applies vertical motion to a feed dog (not shown). The horizontal feed shaft 6 imparts horizontal motion to the feed dog. The shuttle shaft 8 rotates the shuttle in synchronization with the needle bar. The rod 28 and the feed arm 32
The vertical feed shaft 4 and the horizontal feed shaft 6 are connected. Sprockets 14 and 16 are fixed to the upper shaft 2 and the vertical feed shaft 4, respectively, and the rotation of the upper shaft 2 can be transmitted to the vertical feed shaft 4 by a timing belt 18. This sprayet 1
4, 16 and the timing belt 18 constitute a first connecting means. The rotation of the vertical feed shaft 4 is transmitted to the shuttle shaft 8 by the gears 34 and 38. A thread trimmer cam and a shuttle (not shown) are fixed to the shuttle shaft 8 with set screws. Frame 20,
Lubricating oil is stored in a hermetically sealed lubrication chamber 40 surrounded by 20A, 20B and a bottom cover (not shown). ing.

Next, a characteristic portion of this embodiment will be described. The sprocket 50 has a hole 5 into which a hollow shaft 52 is inserted.
0A and holes 50B having a smaller diameter than the holes 50A and into which the vertical feed shaft 4 is inserted are formed, and screw holes 54A and 56A for the set screws 54 and 56 are formed in the respective holes. . The inner diameter of the hollow shaft 52 is slightly larger than the outer diameter of the vertical feed shaft 4, and the vertical feed shaft 4 is loosely fitted so that the vertical feed shaft 4 can rotate smoothly.

The sprocket 50 is fixed to the hollow shaft 52 by a set screw 54, and the gear 34 meshing with the gear 38 is fixed to the outer peripheral portion 52 B of the hollow shaft 52 by a set screw 64. Further, the sprocket 50 is fixed to the vertical feed shaft 4 by a set screw 56 constituting a connecting member. As in the conventional example, a horizontal feed cam 24 is fixed to the vertical feed shaft 4 by a set screw 26, and a vertical feed cam is fixed to a distal end (not shown in the drawing) (not shown) by a set screw.

The above four set screws 26, 54, 56,
Out of 64, a set screw 56 for fixing the sprocket 50 and the vertical feed shaft 4 and a set screw 54 for fixing the sprocket 50 and the hollow shaft 52 are arranged outside the lubrication chamber 40, and the other set screws 26, 64. Are disposed inside the lubrication chamber 40.

In the above construction, when only the timing of the feed movement is changed with respect to the movement of the needle, the set screw 56 which fixes the sprocket 50 and the vertical feed shaft 4 is loosened, and the vertical feed with respect to the sprocket 50 is performed. The shaft 4 may be shifted in the rotational direction by a required amount and then fixed again. At this time, since the sprocket 50 and the hollow shaft 52 have been fixed by the set screw 54, the hollow shaft 52 is set by the set screw 64.
The timing of the rotation of the hook shaft 8 via the gear 34 fixed to the shaft is not changed. Therefore, there is no need to readjust the timing of the thread trimming cam fixed to the shuttle shaft 8 and the shuttle, and the operation can be greatly reduced. Even if the timing of the shuttle is slightly deviated from the predetermined timing, the quality of sewing will be affected. However, it is not necessary to re-adjust the timing, so that the state before the change operation can be reliably maintained.

If it is necessary to change the timing of the shuttle and the thread cutting in response to the movement of the needle bar, the set screw 54 may be loosened and the hollow shaft 52 may be shifted by a required amount in the rotation direction and then fixed again.

Next, a second embodiment of the sewing machine driving apparatus according to the present invention will be described with reference to FIGS. This driving device is different from the first embodiment in that the hollow shaft 5 shown in FIG.
2 is formed integrally with the sprocket 60 attached to the vertical feed shaft 4 and the set screw 54 for fixing the hollow shaft 52 of the first embodiment is unnecessary. Therefore, only one hole 62A for a set screw is formed, and the other points are the same. The vertical feed shaft 4 is inserted into the inner peripheral portion 60A of the sprocket 60 and fixed by a set screw 62 through a hole 62A, and the gear 34 is fixed to the outer peripheral portion 60B by a set screw 64 constituting a connecting member. .

In the present embodiment, of the three set screws 26, 62, 64, the set screw 62 for fixing the sprocket 50 and the vertical feed shaft 4 is disposed outside the lubrication chamber 40, and the other set screws are provided. The screws 26 and 64 are arranged inside the lubrication chamber 40.

In the above configuration, when only the timing of the feed movement is changed with respect to the movement of the needle, the set screw 62 fixing the vertical feed shaft 4 to the sprocket 60 is loosened, and the vertical feed The shaft 4 may be shifted in the rotational direction by a required amount and then fixed again. At this time, since the sprocket 60 and the gear 34 remain fixed by the set screw 64, the shuttle shaft 8
The timing of the rotation of is not changed. Therefore, as in the case of the first embodiment, there is no need to readjust the timing of the thread trimming cam fixed to the shuttle shaft 8 and the shuttle, and the operation can be greatly reduced. Even if the timing of the shuttle is slightly deviated from the predetermined timing, the sewing quality is affected. Therefore, it is not necessary to re-adjust the sewing timing, so that the state before the change operation can be reliably maintained.

This embodiment has an advantage that the number of parts is smaller than that of the first embodiment. In addition, in the case of this embodiment, the shuttle,
When changing the thread trimming timing, it is necessary to loosen the set screw 64 in the lubrication chamber 40 and shift the gear 34 in the rotational direction by a required amount and fix it. It is unlikely that the timing will be changed by the same amount at the same time, so there is no substantial disadvantage.

Although the present invention has been described based on the embodiments shown in the drawings, the present invention is not limited to these embodiments and can be variously modified.

[0025]

The driving device for a sewing machine according to the present invention is provided on a first connecting member for connecting the vertical feed shaft and the horizontal feed shaft, a shuttle shaft for rotating the shuttle in synchronization with the needle bar, and a vertical feed shaft. A transmission means having a transmission member for transmitting rotation of the upper shaft to the vertical feed shaft, a second connection member for connecting the transmission member and the shuttle shaft, and connecting or blocking the transmission member and the vertical feed shaft. And a connecting member.

Since the connecting member is provided independently of the second connecting member, the transmitting member and the vertical feed shaft are connected by the connecting member while the interlocking of the transmitting member and the shuttle shaft by the second connecting member is maintained. Can be connected or cut off. To change only the timing of the feed movement with respect to the movement of the needle, the fixing to the vertical feed shaft may be released by a connecting member, and the vertical feed shaft may be shifted by a required amount in the rotational direction and fixed. At this time, since the vertical feed shaft and the gear remain integral, the timing of rotation of the shuttle shaft via this gear is not changed. Therefore, there is no need to readjust the timing of the thread trimming cam fixed to the shuttle shaft or the shuttle, and the operation can be greatly reduced. Further, if the timing of the shuttle is slightly deviated from the predetermined timing, the sewing quality is affected. Therefore, it is not necessary to adjust the sewing quality, and the state before the change operation can be reliably maintained.

When the coupling member is provided outside the sealed lubrication chamber, it is not necessary to open the sealed lubrication chamber to release the fixing of the coupling member to the vertical feed shaft. It is greatly improved.

[Brief description of the drawings]

FIG. 1 is a bottom view of a first embodiment of a driving device for a sewing machine according to the present invention.

FIG. 2 is a perspective view of a sprocket and a hollow shaft according to the first embodiment.

FIG. 3 is a bottom view of a second embodiment of the driving device of the sewing machine according to the present invention.

FIG. 4 is a perspective view of a sprocket integrally formed with a hollow shaft according to a second embodiment.

FIG. 5 is a bottom view of a driving device for a sewing machine according to a conventional example.

[Explanation of symbols]

2. Upper shaft 4. Vertical feed shaft 6. Horizontal feed shaft 8. Hook shaft 14, 18, 50, 52, 60 ... Transmission member 2.
8, 32 ... first connecting member 34, 38, 64 ... second connecting member 40 ... lubrication chamber 52, 60C ... hollow member 56, 62 ... connecting member

Claims (4)

[Claims] 1. An upper shaft that rotates a needle bar up and down by driving a sewing machine motor, a vertical feed shaft that imparts vertical motion to a feed dog, and a horizontal feed that imparts horizontal motion to a feed dog. A first connecting means for connecting the vertical feed shaft and the horizontal feed shaft; a shuttle shaft for rotating the shuttle in synchronization with a needle bar; and a transmission member provided on the vertical feed shaft. Transmitting means for transmitting the rotation of the shaft to the vertical feed shaft; second connecting means for connecting the transmitting member and the shuttle shaft; and a connecting member capable of connecting or blocking the transmitting member and the vertical feed shaft. A driving device for a sewing machine, comprising: 2. A driving device for a sewing machine according to claim 1, wherein said transmission means has a hollow shaft capable of loosely fitting a vertical feed shaft to an inner peripheral portion and connecting said shuttle shaft to an outer peripheral portion. A driving device for a sewing machine, comprising: a sprocket fixed to the hollow shaft and having the other end linked to the vertical feed shaft by the coupling member. 3. The driving device for a sewing machine according to claim 1, wherein the transmission means includes a hollow shaft capable of inserting a vertical feed shaft into an inner peripheral portion and connecting the shuttle shaft to an outer peripheral portion; A driving device for a sewing machine, comprising a sprocket integrally connected to a hollow shaft and having the other end connected to the vertical feed shaft by the coupling member. 4. The driving device for a sewing machine according to claim 1, wherein the coupling member is disposed outside a sealed lubrication chamber.