Sewing machine

Abstract

To make it easy to retrofit and remove a thread take-up lever suspension device to and from a conventional sewing machine head and maintain the thread take-up lever suspension device by downsizing the thread take-up lever suspension device and reducing change of a thread take-up lever drive mechanism from a conventional mechanism.SOLUTION: A thread take-up lever drive mechanism 27 comprises: a cam 21 having a cam groove 22 rotating with a main axis 3; and a thread take-up lever drive lever 24 having a cam follower 25 to be fitted in the cam groove and an action part 26 acting on a thread take-up lever 12. A thread take-up lever suspension device 30 comprises: a slide guide 31 provided on the thread take-up lever drive lever; a follower axis 32 that is provided so as to be slidable in a cam direction and a counter-cam direction in the slide guide and has the cam follower on a tip thereof; suspension means 33 to pull the follower axis in the counter-cam direction and pull out the cam follower from the cam groove; and suspension release means 35 to fit the cam follower in the cam groove by pushing the follow axis in the cam direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a sewing machine having multiple sewing heads. [Background technology]

[0002] In a sewing machine equipped with multiple sewing machine heads, the needle bars and thread take-up levers of all the sewing machine heads are normally driven by the rotation of a main shaft, which is a common drive source that passes through all the sewing machine heads. However, there are cases where some of the sewing machine heads are stopped and used. Generally, in the sewing machine heads that are stopped, the edge between the main shaft and the needle bar is cut off, and the drive of the needle bar is stopped so that sewing is not performed, but the thread take-up lever continues to be driven and swing.

[0003] As shown in Figure 8, the thread take-up drive mechanism 50 is composed of a cam 51 having a cam groove 52 that rotates together with a main shaft 53, a cam follower 55 that engages with the cam groove 52, and a thread take-up drive lever 54 that has an acting portion 56 that acts on a thread take-up 57. The cam follower 55 rolls within the grooved cam 52, and the thread take-up drive lever 54 swings due to its output displacement, thereby transmitting the power generated by the rotation of the cam 51 to the thread take-up 57. The thread take-up 57 repeatedly swings between the top dead center position shown in Figure 8(b) and the bottom dead center position shown in Figure 8(c) at the same frequency as the mechanical operation (for example, 200 to 300 times per minute) that causes the needle to drop into the fabric.

[0004] As a result, the thread take-up 57 continues to squeeze the same part of the thread that is not being fed because sewing is not being performed, causing damage to the thread or causing the thread to break. If the thread breaks, it is necessary to stop the machine and re-tie the thread, which leads to a decrease in production efficiency. Therefore, it has been considered to stop the oscillation of the take-up lever when the sewing machine head is stopped.

[0005] Patent Document 1 discloses a balance stopping device that controls an axis moving mechanism that rotates an eccentric shaft to move the eccentric shaft portion toward or away from the balance, and while engaging the driven portion of the drive arm with the cam groove of the drive cam, disengages the drive portion of the drive arm from the driven portion of the balance to stop the swinging of the balance, and holds the balance in a position approximately at top dead center by the holding action of a balance holding mechanism.

[0006] Patent Document 2 discloses a balance resting device in which the balance drive lever is divided into a first lever having a cam follower engaged with a cam groove, a second lever engaged with the balance, and a connecting lever having one end journaled on the second lever and the other end connected to the first lever so as to be freely engageable and detachable, and the connecting lever is detached from the first lever when the balance is at rest.

[0007] With these take-up lever pausing devices, when the take-up lever is at rest, the drive arm in Patent Document 1 and the first lever in Patent Document 2 continue to swing while connected to the drive cam (i.e., few parts are paused), so the swinging generates vibration and noise and leads to a shortened lifespan of the parts. Also, because it is necessary to change the take-up drive mechanism from the conventional mechanism many times, it is difficult to retrofit these take-up lever pausing devices to the conventional sewing machine head or to remove them after retrofitting, which is also disadvantageous in terms of maintenance.

[0008] Furthermore, Patent Document 3 discloses a balance rest device in which a swinging member (balance drive lever) is attached to a movable shaft so that it can move axially together with the movable shaft, and the movement is controlled by an electromagnetic solenoid, thereby moving the cam follower together with the balance drive lever and causing it to escape from the cam groove of the cam.

[0009] With this take-up lever pause device, the swinging of the take-up lever drive lever also stops when the take-up lever is at rest, reducing vibration and noise and preventing the life of parts from being shortened. However, because the entire take-up lever drive lever must be moved to release the cam follower from the cam groove, a large-capacity, large-scale electromagnetic solenoid is required, and the take-up drive mechanism must be significantly modified from the conventional mechanism, for example by making the shaft of the take-up lever a movable shaft. Therefore, it is difficult to retrofit this take-up lever pause device to a conventional sewing machine head or to remove it after retrofitting, and it is also disadvantageous in terms of maintenance. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Publication No. 9-75569 [Patent Document 2] Japanese Patent Application Publication No. 10-57651 [Patent Document 3] Japanese Patent Application Publication No. 2-23988 Summary of the Invention [Problem to be solved by the invention]

[0011] Therefore, the object of the present invention is not only to reduce the generation of vibrations and noise when the thread take-up lever is at rest and to extend the life of the parts, but also to make the thread take-up lever rest device smaller and to reduce the changes required to the thread take-up lever drive mechanism from the conventional mechanism, thereby facilitating the retrofitting, removal and maintenance of the thread take-up lever rest device to conventional sewing machine heads. [Means for solving the problem]

[0012] [1] In a sewing machine having a plurality of sewing machine heads, when the operation of some of the sewing machine heads is stopped, the drive of the needle bar and thread take-up of the sewing machine heads is stopped, the balance drive mechanism includes a cam having a cam groove that rotates together with the main shaft, and a balance drive lever having a cam follower that engages with the cam groove and an acting portion that engages with the balance; A sewing machine characterized in that the thread take-up pause device includes a slide guide provided on the thread take-up drive lever, a follower shaft provided within the slide guide so as to be slidable in the cam direction and the counter-cam direction and having a cam follower provided at its tip, pause means for pulling the follower shaft in the counter-cam direction to pull the cam follower out of the cam groove, and pause release means for pushing the follower shaft in the cam direction to engage the cam follower into the cam groove.

[0013] (action) When the cam follower is pulled out of the cam groove by the balance stop device, the swing of the balance drive lever stops along with the balance, thereby suppressing the generation of vibration and noise and improving the lifespan of the parts. Furthermore, since a slide guide is provided on the balance drive lever and the follower shaft is slidably arranged within the slide guide, the balance pause device can be made smaller and there is no need to make major changes to the balance drive mechanism from the conventional mechanism, such as making the shaft of the oscillating member a movable shaft, as in Patent Document 3.

[0014] [2] The sewing machine according to [1], wherein the resting means is a rear portion of the follower shaft for manually pulling the follower shaft.

[0015] [3] The sewing machine according to [1], wherein the pause means is an electromagnetic force device or a fluid pressure device having an engaging portion that engages with the rear portion of the follower shaft to pull the follower shaft by electromagnetic force or fluid pressure.

[0016] [4] The sewing machine according to [3], wherein the engaging portion engages with the rear portion of the follower shaft when the follower shaft is displaced in the output displacement direction of the cam groove.

[0017] [5] The sewing machine according to any one of [1] to [4], wherein the pause release member is a spring.

[0018] [6] A sewing machine according to any one of [1] to [5], wherein the thread take-up pause device includes a stopper member that prevents the follower shaft from shifting in the output displacement direction of the cam groove and in the opposite direction when the follower shaft is pulled. [Effects of the Invention]

[0019] According to the present invention, not only can the generation of vibrations and noise when the thread take-up lever is at rest be suppressed and the life of parts be extended, but the thread take-up lever pause device can also be made smaller and the changes required to the thread take-up lever drive mechanism from the conventional mechanism can be reduced, making it easier to retrofit, remove and maintain the thread take-up lever pause device on conventional sewing machine heads. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a front view of a sewing machine according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the sewing machine. [Figure 3] FIG. 3 shows the thread take-up of the sewing machine in operation, with (a) being a perspective view, (b) being a cross-sectional view, and (c) being a side view. [Figure 4] Figure 4 shows the thread take-up of the sewing machine at rest, (a) being a perspective view, (b) being a cross-sectional view, and (c) being a side view. [Figure 5] FIG. 5 is a perspective view of the pause means of the thread take-up pause device in the sewing machine of the second embodiment. [Figure 6] FIG. 6 shows the operation of the thread take-up lever of the sewing machine, where (a) is a perspective view and (b) is a cross-sectional view. [Figure 7] FIG. 7 shows the sewing machine when the thread take-up lever is at rest, (a) being a perspective view and (b) being a cross-sectional view. [Figure 8] FIG. 8 shows the thread take-up of a conventional sewing machine when it is in operation, where (a) is a perspective view, (b) is a side view when the thread take-up is at the top dead center position, and (c) is a side view when the thread take-up is at the bottom dead center position. DETAILED DESCRIPTION OF THE INVENTION

[0021] 1. Balance drive lever Although there are no particular limitations on the balance drive lever, it is preferable that it does not move in the axial direction of the lever shaft, which is the center of its swing, in order to reduce the number of changes required from the conventional balance drive mechanism. The balance drive lever is not particularly limited, but is preferably one that is not divided into two or more parts that perform different movements, i.e., a balance drive lever that performs one movement as a whole, because this reduces the number of parts.

[0022] 2. Slide guide The slide guide is provided on the balance drive lever and moves together with the swing of the balance drive lever. The method of attaching the slide guide to the balance drive lever is not particularly limited, but examples include integral formation and attachment. The slide guide is not particularly limited, but examples thereof include a tube, a groove, and an opposing wall.

[0023] 3. Pausing means (rear of the follower shaft for manually pulling the follower shaft) The rear part of the follower shaft is not particularly limited as long as it can be grasped with fingers, but examples include a rear part of the follower shaft that is simply extended, a rear part of the follower shaft with an uneven surface to prevent fingers from slipping, and a rear part of the follower shaft with an enlarged knob or hook to allow fingers to hook onto it.

[0024] 4. Pausing means (an electromagnetic force device or fluid pressure device having an engaging portion that engages with the rear portion of the follower shaft to pull the follower shaft by electromagnetic force or fluid pressure) As described above, it is preferable that the engaging portion engages with the rear portion of the follower shaft when the follower shaft is displaced in the output displacement direction of the cam groove. Examples of the electromagnetic device include an electromagnetic solenoid and a motor. An example of the fluid pressure device is a fluid pressure cylinder.

[0025] 5. Pause release means The pause canceling means is not particularly limited, but examples include a spring, an electromagnetic force (electromagnetic solenoid, motor, etc.), a fluid pressure (fluid pressure cylinder, etc.), etc. A spring is preferable because it is energy-efficient and has a simple structure.

[0026] 6.Slip prevention means The slippage prevention means is not particularly limited, but examples thereof include a slippage prevention member that mechanically locks the rear portion of the follower shaft, and a slippage prevention device that attracts the rear portion of the follower shaft with electromagnetic force. [Example]

[0027] The following describes embodiments of the present invention with reference to the drawings. Note that the structures, materials, numerical values, shapes, and dimensions described in the embodiments are merely examples and can be modified as appropriate without departing from the scope of the invention.

[0028] [Example 1] The sewing machine of Example 1 shown in Figures 1 to 4 includes a machine frame 1, a plurality of sewing machine heads 2 arranged side by side at intervals in the horizontal direction on the machine frame 1, a main shaft 3 passing through the plurality of sewing machine heads 2, a motor 4 for driving the main shaft 3, and a plurality of beds 5 arranged side by side so as to be located below each sewing machine head 2. The bed 5 includes a needle plate 6 and a shuttle 7. The needles 17 of the sewing machine heads 2 cooperate with the shuttle 7 of the bed 5 to sew fabric.

[0029] As shown in FIGS. 1 and 2, the sewing machine head 2 is composed of an arm portion 20 fixed to the machine frame 1, and a slide portion 10 supported on the front portion of the arm portion 20 so as to be slidable laterally.

[0030] A balance shaft 11 extending in the horizontal direction is installed above the slide section 10. The balance shaft 11 supports balances 12 in a swingable manner at a midpoint in the length direction thereof, so that eight balances 12 are arranged side by side at intervals in the horizontal direction. The thread take-up 12 has a notch 13 formed at the base end, a slit 14 formed at the bottom, and a threading hole 15 formed at the tip.

[0031] Eight needle bars 16 are arranged in parallel at intervals in the horizontal direction below the slide portion 10, and a needle 17 is attached to the lower end of each needle bar 16. Eight tension regulators 18 are provided on the front surface of the slide portion 10. Eight upper threads (not shown) are supplied from a bobbin (not shown) to the needle 17 via the threading holes 15 of the thread take-up lever 12 and the tension regulators 18.

[0032] Then, by sliding the slide portion 10 sideways using a color change device (not shown), only one set of needle bar 16 and thread take-up lever 12 is selectively indexed to the sewing position, i.e., the position of bed 5, thereby allowing the color of eight upper threads to be changed.

[0033] 2 and 3, the main shaft 3 passes through the arm portion 20, and a cam 21 that rotates together with the main shaft 3 is contained within the arm portion 20. The cam 21 has an endless cam groove 22 that has a predetermined output displacement. A lever shaft 23 extending laterally is installed above the main shaft 3 of the arm portion 20. A thread take-up drive lever 24 is supported midway along its length by the lever shaft 23 and is swingable. The thread take-up drive lever 24 moves in one movement as a whole and is, for example, V-shaped. The thread take-up drive lever 24 does not move in the axial direction of the lever shaft 23, which is the center of its swing. The lever shaft 23 also does not move in the axial direction. These points are the same as those of conventional sewing machines.

[0034] 3 and 4, the thread take-up drive lever 24 has a cam follower 25 (for example, a rotatable roller) at its base end that engages with the cam groove 22, and an acting portion 26 (for example, a rotatable roller) at its tip end that engages with the notch 13 of the thread take-up 12. The cam 21 and the thread take-up drive lever 24 form a thread take-up drive mechanism 27 that transmits the power of the main shaft 3 to one thread take-up 12 that is selectively indexed to the sewing position.

[0035] A balance stop device 30 is provided on the base end side of the balance drive lever 24, which pulls the cam follower 25 out of the cam groove 22 to stop the balance 12. The balance stop device 30 is A slide guide 31 provided on the balance drive lever 24; A follower shaft 32 is provided in the slide guide 31 so as to be slidable in the cam direction and the counter-cam direction, and has a cam follower 25 provided at its tip end; A stopping means 33 that pulls the follower shaft 32 in the direction opposite to the cam to remove the cam follower 25 from the cam groove 22; a displacement prevention means 34 for preventing the follower shaft 32 from shifting in the output displacement direction of the cam groove 22 when the follower shaft 32 is pulled; The cam follower shaft 32 is pushed in the cam direction to cause the cam follower 25 to engage with the cam groove 22.

[0036] The slide guide 31 consists of a cylinder integrally formed with or attached to the base end side of the balance drive lever 24, and the hole in the cylinder also passes through the balance drive lever 24. The cylinder has a base wall with a reduced diameter hole that is smaller than the inner diameter of the cylinder hole.

[0037] The follower shaft 32 includes a thick front portion that slides within the slide guide 31 and a thin rear portion that slides within the reduced diameter hole of the slide guide 31, with a step between the front and rear portions. The rear portion can protrude outside the slide guide 31. The cam follower 25 can enter the slide guide 31 when pulled.

[0038] The pause means 33 is a rear portion of the follower shaft 32 for manually pulling the follower shaft 32, and more specifically, a knob (33) at the rear portion of the follower shaft 32 that is enlarged in diameter so that a finger can hook onto it. When the knob (33) is pinched with fingers and the follower shaft 32 is manually pulled in the direction opposite to the cam against the elastic force of the pause release means 35, the cam follower 25 is pulled out of the cam groove 22. With the cam follower 25 pulled out, even if the main shaft 3 and cam 21 rotate, power is not transmitted to the balance drive lever 24, and the balance 12 comes to a pause (Fig. 4).

[0039] The slippage prevention means 34 is a fork-shaped member provided around the position where the knob (33) is pulled, which pinches and stops the cam follower 25 so that it does not slip in the output displacement direction of the cam groove 22 or in the opposite direction. A stopper (not shown) is also provided to prevent the knob (33) from returning in the cam direction from the pulled position.

[0040] The pause release means 35 is a coil spring that is fitted onto the follower shaft 32 and mounted in a compressed state between the stepped portion of the follower shaft 32 and the base wall of the slide guide 31. The resilient force of the spring of this pause release means 35 urges the follower shaft 32 in the cam direction, and the cam follower 25 engages with the cam groove 22 (Fig. 3). When the cam follower 25 engages, power is transmitted to the balance drive lever 24 by the rotation of the main shaft 3 and cam 21, and the balance 12 swings.

[0041] 2, a take-up lever retaining plate 36 protrudes from the arm portion 20 toward the bottom of the take-up lever 12. The tip of the take-up lever retaining plate 36 engages with the slit 14 of the take-up lever 12 when it is not in the sewing position to hold the take-up lever 12 at the top dead center position, and does not engage with the slit 14 of the take-up lever 12 when it is in the sewing position to allow the take-up lever 12 to swing.

[0042] The drive mechanism for needle bar 16 is well known. Cam 21 is provided with an eccentric portion (not shown), which is connected to needle bar 16 via a crank mechanism and a needle bar striker (neither of which are shown). The needle bar striker is supported on arm 20 by vertical shaft 37 so that it can move up and down. The eccentric portion of cam 21, the crank mechanism, and the needle bar striker transmit the power of main shaft 3 to needle bar 16 at the sewing position, thereby driving needle bar 16. The resting device for needle bar 16 is a well-known jump mechanism (not shown), which stops the power of main shaft 3 from being transmitted to needle bar 16 at the sewing position, thereby putting needle bar 16 into a resting state.

[0043] The sewing machine of the first embodiment configured as above can be used as follows. (When all machine heads 2 are in operation) 3, the spring of the pause release means 35 biases the follower shaft 32, maintaining the state in which the cam follower 25 is engaged with the cam groove 22, causing the thread take-up lever 12 to swing between the top dead center position and the bottom dead center position as described above. The needle bar 16 is also driven by the drive mechanism.

[0044] (When stopping operation of some machine heads 2) 4, when an operator pinches the knob 33 at the rear of the follower shaft 32 with his / her fingers and manually pulls the follower shaft 32 in the direction opposite to the cam against the elastic force of the pause release means 35, the cam follower 25 is pulled out of the cam groove 22, and the oscillation of the thread take-up drive lever 24 and the thread take-up 12 is stopped as described above. The needle bar 16 is also stopped by the pause device. In this way, the swinging of the balance drive lever 24 as well as the balance 12 is stopped, so that the generation of vibration and noise is suppressed and the life of the parts is improved. Furthermore, since the slide guide 31 is provided on the balance drive lever 24 and the follower shaft 32 is slidably provided within the slide guide 31, the balance stop device 30 can be made smaller and there is no need to significantly modify the balance drive mechanism 27 from the conventional mechanism (such as by making the shaft of the oscillating member a movable shaft as in Patent Document 3).

[0045] (When the suspension is lifted) During the pause, the anti-slip means 34 clamps and stops the cam follower 25 so that it does not shift in the output displacement direction of the cam groove 22 or in the opposite direction, so that to release the pause, the operator simply presses the knob 33 at the rear of the follower shaft 32 in the cam direction, and together with the elastic force of the spring of the pause release means 35, the cam follower 25 can be smoothly engaged into the cam groove 22. In this way, the state shown in Figure 3 can be restored.

[0046] [Example 2] 5 to 7 differs from Example 1 only in that the pause means 40 is an electromagnetic force device having an engaging portion 43 that engages with the rear portion of the follower shaft 32 to pull the follower shaft 32 by electromagnetic force. Other features of Example 2 are the same as those of Example 1, and the rear portion of the follower shaft 32 is provided with a knob 33 with an enlarged diameter.

[0047] As shown in Figure 5, the electromagnetic force device of the pause means 40 is composed of a bracket 41 attached to the arm portion 20 of the sewing machine head 2, an electromagnetic solenoid 42 (pull solenoid) attached to the bracket 41, and an engagement portion 43 attached to the tip of the movable iron core of the electromagnetic solenoid 42.

[0048] The engagement portion 43 is a T-groove laid on its side, and at one open end in the groove length direction, the groove width is larger than the outer diameter of the knob 33 so that the knob 33 can fit into the T-groove, and at the center in the groove length direction, the groove width is approximately the outer diameter of the knob 33 so that the knob 33 can engage with the T-groove. This change in groove width is due to the inclination of the groove sidewalls. The center in the groove length direction is located on an extension of the follower shaft 32 displaced in the output displacement direction of the cam groove 22, so that the follower shaft 32 engages with the knob 33 when displaced in the output displacement direction of the cam groove 22.

[0049] In addition, fork-shaped anti-slip means 34 is attached to the bracket 41 to pinch and stop the cam follower 25 so that it does not slip in the output displacement direction of the cam groove 22 or in the opposite direction. The anti-slip means 34 is attached so as to be positioned around the position where the knob 33 is pulled.

[0050] The sewing machine of the second embodiment configured as above can be used as follows. (When all machine heads 2 are in operation) 6, the spring of the pause release means 35 biases the follower shaft 32, maintaining the state in which the cam follower 25 is engaged with the cam groove 22, causing the thread take-up 12 to swing as described above. The needle bar 16 is also driven by the drive mechanism.

[0051] (When stopping operation of some machine heads 2) 7, when the electromagnetic solenoid 42 is energized and the follower shaft 32 engaged with the engaging portion 43 is pulled in the direction opposite to the cam against the resilient force of the pause release means 35, the cam follower 25 is pulled out of the cam groove 22, and the oscillation of the thread take-up drive lever 24 and the thread take-up 12 is stopped as described above. The needle bar 16 is also stopped by the pause device. Therefore, it is possible to obtain the same effects as in embodiment 1. Since the electromagnetic solenoid 42 only pulls the follower shaft 32 and the cam follower 25, it is sufficient to have a small capacity and a small size, and the stopping means 40 can be made small in size.

[0052] (When the suspension is lifted) During the pause, the anti-slip means 34 clamps and stops the cam follower 25 so that it does not shift in the output displacement direction of the cam groove 22 or in the opposite direction, so that when the pause is to be released, the electromagnetic solenoid 42 is energized and the spring of the electromagnetic solenoid 42 pushes the knob 33 in the cam direction, and together with the elastic force of the spring of the pause release means 35, the cam follower 25 can be smoothly engaged into the cam groove 22. In this way, the state shown in FIG. 6 can be restored.

[0053] The present invention is not limited to the above-described embodiments, and can be embodied by making appropriate modifications without departing from the spirit of the invention. [Explanation of symbols]

[0054] 2 sewing machine head 3 main axis 10 Slide section 11 Balance axis 12 Balance 13 Notch 16 Needle bar 17 needles 20 Arm section 21 Cam 22 Cam groove 23 Lever shaft 24 Balance drive lever 25 Cam follower 26 Acting part 27 Balance drive mechanism 30 Balance stop device 31 Slide Guide 32 Follower shaft 33 Pause means (pick) 34 Anti-slip means 35 Pause release means (spring) 40 Stopping means (electromagnetic force device) 41 Placket 42 Electromagnetic solenoid 43 Engagement part

Claims

1. In a sewing machine having a plurality of sewing machine heads (2), when the operation of some of the sewing machine heads is stopped, the driving of the needle bar (16) and the thread take-up lever (12) of the sewing machine heads is stopped, The balance drive mechanism (27) includes a cam (21) having a cam groove (22) that rotates together with the main shaft (3), a cam follower (25) that engages with the cam groove, and a balance drive lever (24) that has an acting portion (26) that acts on the balance, A sewing machine characterized in that the thread take-up pause device (30) comprises: a slide guide (31) provided on the thread take-up drive lever; a follower shaft (32) provided within the slide guide so as to be slidable in the cam direction and the counter-cam direction and having a cam follower provided at its tip; pause means (33, 40) for pulling the follower shaft in the counter-cam direction to extract the cam follower from the cam groove; and pause release means (35) for pushing the follower shaft in the cam direction to engage the cam follower into the cam groove.

2. 2. A sewing machine according to claim 1, wherein the rest means (33) is a rear portion of the follower shaft (32) for manually pulling the follower shaft.

3. 2. The sewing machine according to claim 1, wherein the stopping means (40) is an electromagnetic force device or a fluid pressure device having an engaging portion (43) that engages with the rear portion of the follower shaft (32) to pull the follower shaft (32) by electromagnetic force or fluid pressure.

4. 4. The sewing machine according to claim 3, wherein the engaging portion (43) engages with the rear portion of the follower shaft (32) when the follower shaft (32) is displaced in the output displacement direction of the cam groove (22).

5. The sewing machine according to any one of claims 1 to 4, wherein the pause release means (35) is a spring.

6. The sewing machine according to any one of claims 1 to 4, wherein the thread take-up pause device (30) includes a slippage prevention means (34) that prevents the follower shaft (32) from slipping in the output displacement direction of the cam groove (22) and in the opposite direction when the follower shaft (32) is pulled.

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