JPH07289767A - Sewing machine driving device - Google Patents

Abstract

PURPOSE:To prevent to propagate the shock by rotation inertia of a clutch disc by rapid braking to the rotation transmission part from a sub-motor, and to prevent to propagate play etc., of a rotation transmission part on the sub- motor in stopping rotation as the motor pulley rotation direction play. CONSTITUTION:By operating a motor lever 62, a clutch disc 61 mounted on a motor shaft 58 is pressed to a fly wheel 55 mounted on a rotor 52 of a main motor or a rotation member 65, to which rotation from a sub-motor 75 freely rotatable centering on the motor shaft 58 is transmitted, to enable to transmit rotation of a motor pulley 59 mounted on the outer edge of the motor shaft 58 to the sewing machine main shaft via a belt. The driving equipment of a sewing machine constructed as above is provided with a sub-braking device 81 to enable to stop the machine directly braking the rotation member 65.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device for a sewing machine, and more particularly to a layout of auxiliary brakes in a so-called clutch motor for automatically stopping a needle bar at a predetermined position.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a so-called clutch motor CM as a drive device for a conventional sewing machine. The structure of a rotor R portion of a main motor MM, a clutch plate CP, a motor shaft S, and a motor pulley P is as follows. It is the same as a general clutch motor.

In this clutch motor CM, a brake plate B is rotatable with respect to a motor shaft S and a motor frame, and a helical gear G is provided on the outer circumference of the brake plate B. Further, the worm W is provided on the auxiliary motor shaft SS having the auxiliary motor SM for low speed rotation provided at one end and the magnet brake MB provided at the other end. The worm W meshes with the helical gear G.

According to this clutch motor CM, when the motor lever L is pushed down, the clutch plate CP is pressed against the flywheel F to rotate the motor shaft S and the motor pulley P at high speed, as in a general clutch motor.

On the contrary, when the motor lever L is pushed up, the clutch plate CP is brought into pressure contact with the brake plate B provided with the helical gear G. At this time, the magnet brake MB is released by a low speed signal or a needle bar fixed position signal from the outside,
Although the auxiliary motor SM rotates, the rotation of the auxiliary motor SM causes the brake plate B to rotate by the meshing of the worm W and the helical gear G. That is, the pressed clutch plate C
P, the motor shaft S, and the motor pulley P are rotated at a low speed.

Next, the signal to the auxiliary motor SM is turned off by the turning off of the low speed signal or the stop signal, and the low speed rotation of the motor pulley P is stopped by operating the magnet brake MB.

Further, a needle bar fixed position stopping device of a sewing machine using a general clutch motor is actually opened.
It is disclosed in Japanese Patent Publication No. 8 and its configuration is shown in FIG.

In FIG. 5, 1 is a sewing machine head, 19 is a general clutch motor, 14 is a low-speed rotation auxiliary motor for stopping at a fixed position, 7 is a coupling unit having a one-way rotation clutch, and 22 is a clutch motor. An actuator for moving the motor lever 20 of 19 to a position where the clutch plate does not come into contact with either the rotor side or the brake side, and 26 is a switch unit for issuing a top dead center stop command and a bottom dead center stop command signal of the needle bar. Is. Further, FIG. 6 shows the details of the actuator 22 part, and FIG. 7 shows the details of the switch unit 26 part.

Here, the auxiliary motor 14 is connected to the upper shaft 2 of the sewing machine head 1 via the coupling unit 7, and the one-way rotation clutch in the coupling unit 7 rotates in the reverse rotation direction of the sewing machine. It is composed freely.
Further, the rotation of the clutch motor 19 is transmitted to the upper shaft 2 via the flywheel 4 and the belt 37, and the pedal 36 and the motor lever 20 relay the switch unit 26 and are connected by the connecting rods 25 and 29. Switch unit 2
6 includes a top dead center stop position switch 27 and a bottom dead center stop position switch 28, and a lever 32 fixed to a connecting rod 29.
By moving up and down, the switches 27 and 28 are operated.

According to the needle bar fixed position stopping device described above, FIG.
The connecting rod 29 is also pulled down by stepping on the pedal 36 of the compression spring 34 of FIG.
Is set to be weaker than the return spring of the motor lever 20, so first, while compressing the compression spring 34, the connecting rod 2
9 and the lever 32 are lowered to turn on the switch 28. Although the connecting rod 29 is further lowered, the thrust collar 30 fixed to the connecting rod 29 hits the bracket of the switch unit 26.

When the pedal 36 is further stepped forward, the connecting rod 29, the switch unit 26 and the connecting rod 25 fixed to the bracket are integrally pulled down, and the thrust collar 24 fixed to the connecting rod 25 is moved to the position shown in FIG. At, the motor lever 20 is pushed down against its return spring, and finally the clutch plate in the clutch motor 19 is brought into pressure contact with the rotor to give the sewing machine a high-speed rotation. At this time, the rotation of the clutch motor 19 is transmitted to the upper shaft 2 via the belt 37 and the flywheel 4, but is not transmitted to the auxiliary motor 14 by the one-way rotating clutch in the coupling unit 7.

Next, when the pedal 36 is returned to the initial position, the series of movements described above proceeds in reverse, and finally the lever 32 fixed to the connecting rod 29 is operated by the switch 28 by the returning force of the compression spring 34. Then, the switch 28 is turned off. A command to stop the needle bar bottom dead center position is issued to the control box 35 by the ON → OFF signal of the switch 28.
As a result, first, the actuator 22 of FIG. 6 operates.

Since the actuator 22 main body is fixed to the motor lever 20 and the push-side plunger 38 is in contact with the motor frame, the actuator 22 is actuated to push down the motor lever 20. Since the pressing amount of the motor lever 20 is set to a position where the clutch plate in the clutch motor 19 does not come into contact with either the rotor side or the brake side, that is, the operation of the actuator 22 causes the motor shaft of the clutch motor 19 to move. Free to rotate.

Next, the auxiliary motor 14 is rotated to rotate the upper shaft 2 via the one-way rotating clutch in the coupling unit 7. When the upper shaft 2 continues to rotate and the bottom dead center position signal provided on the flywheel 4 or the coupling unit 7 is received, the rotation of the auxiliary motor 14 is stopped and the actuator 22 is turned off. By returning by the return spring force, the clutch plate in the clutch motor 19 is pressed against the brake plate, and the sewing machine is stopped by the brake force.

When the pedal 36 is further depressed, the connecting rod 25 and the switch unit 2 fixed to the connecting rod 25.
Since the bracket 6 is restricted from moving upward by the connecting rod 25 and the motor frame, the connecting rod 29 and the lever 32 fixed to the connecting rod 29 are compressed by the compression spring 33.
When the switch 27 is turned on, the thrust collar 31 fixed to the connecting rod 29 hits the switch bracket and is pushed up, that is, the rear depression of the pedal 36 is stopped.

When the switch 27 is turned on, a needle bar top dead center position stop command is issued to the control box 35. As a result, similarly to the bottom dead center position stopping operation described above, the actuator 22 and the auxiliary motor 14 are operated, and the top dead center position signal provided in the flywheel 4 or the coupling unit 7 is received, whereby the bottom dead center position is received. It operates in the same way as the stop operation and stops the sewing machine.

[0017]

However, the conventional clutch motor CM shown in FIG. 4 has the following problems.

When abrupt braking is performed, the inertia force due to the rotation of the clutch plate CP is the helical gear G and the worm W.
It will be applied to the meshing part of and will easily become an impact force.

Since the brake is engaged with the helical gear G and the worm W, at least the helical gear G is used.
The backlash of the worm W has a play in the rotation direction of the motor pulley P.

When the magnet brake MB becomes defective and the brake does not work, the rotation of the motor pulley P cannot be stopped. If the magnet brake MB is removed for replacement or repair, it cannot be used as a normal clutch motor.

Further, the conventional needle bar fixed position stopping device shown in FIGS. 5 to 7 has the following problems.

When stopping the top dead center and the bottom dead center, first, the motor lever 20 must be first pushed down to a position where the clutch plate does not come into contact with either the rotor side or the brake side, and then the auxiliary motor 14 must be operated. However, the operation becomes gradual, a series of fixed-position stop operations require time, and the cycle time is long.

In contrast to the conventional clutch motor, in addition to the two positions on the rotation side and the stop side, a neutral position which does not contact with either of them is used, so that the section must be sufficiently secured, and the pedal 36 It is not possible to extremely reduce the front stroke of the. If the stroke is to be reduced, the motor lever 2 by the actuator 22
The accuracy of the movement amount of 0 must be extremely increased.

Due to wear of the clutch plate and the brake plate,
Alternatively, since the position of the motor lever 20 changes due to replacement of parts due to the abrasion, the position adjustment of the actuator 22 with respect to the motor lever 20 is required.

If the return spring pressure of the motor lever 20 is adjusted to be extremely strong, the operation of the actuator 22 becomes insufficient, so that the clutch plate cannot be completely separated from the brake plate, and the motor shaft 14 is overloaded by the brake. In order to rotate the auxiliary motor 14 under
The one-way rotating clutch in the auxiliary motor 14 or the coupling unit 7 is damaged.

Therefore, an object of the present invention is to prevent an impact force due to the rotational inertial force of the clutch plate in a sudden braking from being applied to the rotation transmitting portion from the auxiliary motor, and to transmit the rotation from the auxiliary motor in the stopped rotation. It is an object of the present invention to provide a driving device for a sewing machine in which rattling of a portion is prevented from being transmitted as rattling in the rotation direction of a motor pulley.

[0027]

In order to solve the above problems, the present invention provides a main motor, an auxiliary motor, a motor shaft, a flywheel integrally provided on a rotor of the main motor, and the flywheel. A clutch plate that is integrally provided on the motor shaft so as to face the motor shaft, a rotary member that is rotatable about the motor shaft on the side opposite to the flywheel with the clutch plate sandwiched between the rotary plate, and the auxiliary motor. A rotation transmission device that transmits rotation from the motor shaft, a motor pulley provided at an outer end portion of the motor shaft, and a motor lever that allows the motor shaft to be moved and operated. In a drive device for a sewing machine, which is brought into pressure contact with a flywheel or the rotating member to transmit the rotation of the motor pulley to a sewing machine main shaft via a belt. It is characterized in configuration with an auxiliary braking device to be stopped by braking the rotary member directly.

The auxiliary brake device may be, for example,
It has a spring for holding the rotating member in a braking state.

The rotation transmission device is, for example, a gear mechanism provided between the auxiliary motor shaft and the rotating member.

The rotation transmission device is, for example, a timing belt device provided between the auxiliary motor shaft and the rotating member.

[0031]

According to the present invention, the rotating member, which is free to rotate about the motor shaft and to which the rotation from the auxiliary motor is transmitted, is directly braked by the auxiliary braking device to stop, so that it is possible to assist the sudden braking. No impact force due to the rotational inertia of the clutch plate is applied to the rotation transmission part from the motor to the rotating member, and the rattling of the rotation transmission part from the auxiliary motor to the rotating member when rotation is stopped is the play in the rotation direction of the motor pulley. I can't get it.

Since the motor shaft is not freely rotatable by setting the motor lever to the neutral position,
Regardless of the amount of movement of the motor lever and the return spring force of the motor lever, it is possible to stably and freely rotate a motor shaft provided with a flywheel provided on the rotor of the main motor or a clutch plate that is brought into pressure contact with a rotating member.

If the auxiliary brake device is provided with a spring that holds the rotating member in a braking state, the braking performance can be maintained by the spring force of the auxiliary brake spring even if the actuator fails.

Further, if a gear mechanism is used as a rotation transmission device from the auxiliary motor to the rotating member, an impact force due to the rotational inertia of the clutch plate is not applied to the gear meshing portion against a sudden brake, and the rotation is prevented. The backlash at the gear meshing part when stopped is not transmitted as backlash in the rotation direction of the motor pulley.

Alternatively, if a timing belt device is used as a rotation transmission device from the auxiliary motor to the rotating member, an impact force due to the rotational inertia force of the clutch plate is applied to the meshing portion of the timing pulley and the timing belt against a sudden brake. Moreover, the play of the meshing portion between the timing pulley and the timing belt when the rotation is stopped and the deflection of the timing belt are not transmitted as the play in the rotation direction of the motor pulley.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a driving device for a sewing machine according to the present invention will be described below with reference to FIGS.

First, FIG. 1 shows a clutch motor portion as an example to which a driving device for a sewing machine according to the present invention is applied, showing a first embodiment, 50 is a clutch motor, 51 is a motor frame, and 52 is a motor frame. Is the rotor of the main motor,
55 is a flywheel, 56 is a slide sleeve, 58
Is a motor shaft, 59 is a motor pulley, 61 is a clutch plate,
62 is a motor lever, 64 is a motor lever return spring, 6
5 is a rotating member, 66 is a helical gear, 67 is a brake plate,
71 is a worm, 72 is an auxiliary motor shaft, 74 is a rotation transmission device, 75 is an auxiliary motor, 81 is an auxiliary braking device, 8
2 is an auxiliary brake pad, 84 is an auxiliary brake spring, 8
7 is an actuator.

As shown in the figure, the clutch motor 50 accommodates a rotor 52 of a main motor in a motor frame 51, and a rotor shaft 53 thereof is rotatably supported by bearings 54, 54. A flywheel 55 is integrally provided at the right end of the rotor shaft 53 in the figure. A slide sleeve 56 is slidably incorporated in the right end portion of the motor frame 51 in the figure, and a motor shaft 58 is rotatably supported in the slide sleeve 56 via bearings 57, 57. The motor shaft 58 and the rotor shaft 53 are arranged on the same axis.

The motor shaft 58 is connected to the motor frame 51.
A motor pulley 59 is integrally provided at an outer end portion projecting from the outside, and a clutch plate 61 is integrally provided at an inner end portion projecting into the motor frame 51. The clutch plate 61 faces a position facing the flywheel 55.
A belt (not shown) is hung on the motor pulley 59, and the belt is also hung on a pulley provided on the upper shaft of the sewing machine head as is well known (not shown).

A motor lever 62 is connected to the slide sleeve 56. This motor lever 6
2 is swingable around a pin 63 that supports a motor lever 62 on a motor frame 51. The connecting portion of the motor lever 62 with the slide sleeve 56 and the pin 6
3, one end of a motor lever return spring 64 by a tension coil spring for biasing the slide sleeve 56 to the right in the figure is locked. The other end of the motor lever return spring 64 is locked to the right side of the motor frame 51 in the figure.

On the shaft of the motor shaft 58 between the slide sleeve 56 and the clutch plate 61,
The rotating member 65 is assembled to be freely rotatable (rotatably). This rotating member 65 has a helical gear 66 on the left side of the drawing.
And a brake plate 67 is integrally formed on the right side of each. The rotating member 65 is rotatably supported by the motor frame 51 via a bearing 68 at the right end in the figure.

Further, a worm 71 which is orthogonal to the helical gear 66 and meshes with the helical gear 66 is arranged.
1 is provided integrally with the auxiliary motor shaft 72. The auxiliary motor shaft 72 has a bearing 73 on the outer peripheral portion of the motor frame 51.
It is rotatably supported via. This auxiliary motor shaft 7
The auxiliary motor 75 having the number 2 is fixed to the outer peripheral surface of the motor frame 51 via a motor cover 76. Thus, in order to transmit the rotation from the auxiliary motor 75 to the rotating member 65, the worm 71 of the auxiliary motor shaft 72 and the rotation transmission device 74 including the helical gear 66 are provided.

An auxiliary braking device 81 for braking the brake plate 67 is also provided. The auxiliary brake device 81 is provided with an auxiliary brake pad 82, which comes into pressure contact with the outer peripheral surface of the brake plate 67, integrally with a rod 83, and the auxiliary brake pad 82 is wound around the rod 83 so that the auxiliary brake pad 82 is provided on the outer periphery of the brake plate 67. An auxiliary brake spring 84, which is a compression coil spring for urging the surface in a pressure contact direction,
It is interposed between the auxiliary brake pad 82 and the outer peripheral portion of the motor frame 51.

The left end of the link 85 in the figure is connected to the outer end of the rod 83 projecting from the outer periphery of the motor frame 51. The link 85 includes a pin 86 that supports the motor frame 51 at substantially the center of the link 85.
It can freely swing around. An operating rod 88 of an actuator 87 fixedly provided on the outer peripheral surface of the motor frame 51 is connected to the right end portion of the link 85 in the figure. The actuator 87 is any one of a solenoid, an air cylinder, and a hydraulic cylinder, and may be any other drive source.

The clutch motor 5 having the above structure
The operation of 0 will be described below.

First, the rotor 52 of the main motor is rotating at high speed, and the auxiliary motor 75 is in a stopped state. Further, at this time, the actuator 87 of the auxiliary brake device 81 is in a non-actuated state, and therefore the auxiliary brake pad 82 is
The compression spring force of the auxiliary brake spring 84 maintains the pressure contact with the outer peripheral surface of the brake plate 67. That is, the rotating member 65 having the helical gear 66 is directly braked by the auxiliary brake device 81 to be in a stopped state.

In the above state, the motor lever 62 is moved to the pin 6
The slide sleeve 56 is moved to the left side in the drawing against the tension spring force of the motor lever return spring 64, and the motor shaft 58 is also moved integrally with the motor shaft 58. The integral clutch plate 61 is brought into pressure contact with the flywheel 55 integral with the rotor 52 of the main motor.
Therefore, the rotor 52 of the main motor and the motor shaft 58 are directly connected, that is, the motor pulley 59 integrated with the motor shaft 58 is in a high-speed rotation state.

When a low speed rotation is applied, such as when the needle bar (not shown) is stopped at the top / bottom dead center position, the motor lever 62 is oscillated in the opposite direction to pull the motor lever return spring 64. With the spring force, the clutch plate 61 is pressed against the side surface of the helical gear 66 of the rotating member 65. At this time, the auxiliary brake device 81 is released by the low speed signal or the needle bar fixed position signal from the outside, and the auxiliary motor 75 is rotated.

That is, the actuator 87 is actuated, and the actuating rod 88 is retracted and moved downward, and the pin 8 of the link 85 is moved.
After swinging about 6 times and moving the rod 83 upward, the auxiliary brake pad 82 is separated from the outer peripheral surface of the brake plate 67 against the compression spring force of the auxiliary brake spring 84, and the rotating member 65 is freely rotated. To do. Subsequently, the auxiliary motor 75 starts driving, and the worm 71 provided on the auxiliary motor shaft 72 meshes with the helical gear 66, so that the rotating member 65 rotates at a low speed.

Therefore, since the clutch plate 61 is pressed against the side surface of the helical gear 66 of the rotating member 65 as described above, the rotating member 65 and the clutch plate 61 are directly connected, that is, the motor shaft. The motor pulley 59, which is integral with 58, is in a low speed rotation state.

Then, the driving of the auxiliary motor 75 is stopped by the OFF of the low speed signal or the stop signal, and the rotating member 65 is directly braked and stopped again by the operation of the auxiliary brake device 81. Therefore, the low speed rotation of the motor pulley 59 is stopped.

Next, a second embodiment of the present invention shown in FIG. 2 will be described. In the second embodiment, only the constructions of the auxiliary motor 95 and its rotation transmitting device 94 are different from those of the first embodiment. Therefore, the same members as those in the first embodiment are designated by the same reference numerals and their description is omitted. Will be omitted and only differences from the first embodiment will be described below.

In the second embodiment, as shown in the figure, on the left side of the rotary member 65 in the figure, instead of the helical gear 66,
The timing pulley 69, which is a toothed pulley, is integrally formed. A timing belt 91, which is a toothed belt, is hung on and meshed with the timing pulley 69. The timing belt 91 is also engaged with and meshed with a gear 92.

The gear 92 is provided integrally with the auxiliary motor shaft 93. The auxiliary motor 95 having the auxiliary motor shaft 93 is fixed to the outer peripheral surface of the motor frame 51 via a motor cover 96. Thus, in order to transmit the rotation from the auxiliary motor 95 to the rotating member 65, the gear 92 of the auxiliary motor shaft 93 and the timing belt 91
And a rotation transmission device 94 including a timing pulley 69.

The rotation transmission device 94 of the second embodiment as described above.
Also, by driving the auxiliary motor 95, the timing belt 91 is moved from the gear 92 provided on the auxiliary motor shaft 93.
The low speed rotation can be transmitted to the rotating member 65 via the timing pulley 69. The other operations and the like are the same as those described in the first embodiment.

According to the sewing machine drive apparatus described in the first and second embodiments, the following effects can be obtained.

In contrast to the problem with the conventional clutch motor shown in FIG. 4, since the auxiliary braking device 81 directly applies the braking force to the helical gear 66 or the timing pulley 69, it is possible to prevent sudden braking. As a result, no impact force due to the rotational inertia force of the clutch plate 61 is applied to the meshing portion of the helical gear 66 and the worm 71 or the timing pulley 69 and the timing belt 91.
Further, the backlash of the helical gear 66 and the worm 71, the flexure of the timing belt 91, and the like when the rotation is stopped are not transmitted as a play in the rotation direction of the motor pulley 59.

In contrast to the problems associated with the conventional needle bar fixed position stopping device shown in FIGS. 5 to 7, the motor shaft 58 is not freely rotatable by setting the motor lever 62 to the neutral position. Therefore, regardless of the movement amount of the motor lever 62, that is, the movement amount of the clutch plate 61 and the return spring force of the motor lever 62, the motor shaft 58 can be stably rotated freely.

In contrast to the problem with the conventional clutch motor shown in FIG. 4, even if the actuator 87 fails, the braking force is maintained by the spring force of the auxiliary brake spring 84. Therefore, even if the actuator 87 is removed for replacement or repair, the function as the clutch motor 50 remains.

Next, a third embodiment of the present invention shown in FIG. 3 will be described. In the third embodiment, only the structure of the auxiliary brake device 81 is different from that of the first embodiment, and therefore, the same members as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. Then, only the differences from the first embodiment will be described.

In the third embodiment, as shown in the figure, the auxiliary brake device 81 for braking the brake plate 67 has an auxiliary brake pad 8 which is in pressure contact with the outer peripheral surface of the brake plate 67.
The left end portion of the bell crank 185 in the figure is connected to the outer end portion of the rod 83 integrally provided with 2 protruding from the outer peripheral portion of the motor frame 51. An auxiliary brake spring, which is a compression coil spring for urging the auxiliary brake pad 82 in a direction away from the outer peripheral surface of the brake plate 67 by winding the rod 83 around the portion protruding from the outer peripheral portion of the motor frame 51. 184 is interposed between the outer peripheral portion of the motor frame 51 and the illustrated left end portion of the bell crank 185.

The bell crank 185 is swingable around a pin 186 which supports the motor frame 51 at substantially the center of the bell crank 185. An actuating rod 188 of an actuator 187 is connected to the upper end of the bell crank 185 in the figure. The actuator 187 is fixedly provided on the outer peripheral surface of the motor frame 51 via a bracket 189. The actuator 187 is also a solenoid, an air cylinder, or a hydraulic cylinder, as in the first embodiment, and may be any other drive source.

In the auxiliary brake device 81 of the third embodiment as described above, the forward / backward movement of the operating rod 188 of the actuator 187 is opposite to that of the first embodiment. That is, when the actuator 187 of the auxiliary brake device 81 is actuated, the actuating rod 188 is pulled and moves leftward, and the bell crank 185 swings around the pin 186 and the compression spring force of the auxiliary brake spring 184 of the rod 83 is lowered. After the movement, the auxiliary brake pad 82 is brought into pressure contact with the outer peripheral surface of the brake plate 67, and the rotating member 65 having the helical gear 66 is directly braked to be in a stopped state.

When the auxiliary brake device 81 is released, the actuator 187 is deactivated, the actuation rod 188 advances and moves right, and the pin 1 of the bell crank 185 is released.
After the swing around 86 and the upward movement of the rod 83, the auxiliary brake pad 82 is also assisted by the compression spring force of the auxiliary brake spring 184 and is separated from the outer peripheral surface of the brake plate 67, and the rotating member 65 is freely rotatable. become. The other operations and the like are the same as those described in the first embodiment.

As described above, the structure of the auxiliary brake device 81 described in the third embodiment can be applied to that of the second embodiment.

Auxiliary brake device 81 of the above third embodiment
Even with the clutch motor 50 including the above, among the effects obtained by the driving device of the sewing machine described in the first embodiment and the second embodiment, except for the above effect,
The effect of is obtained.

In the above embodiments, the driving device for the sewing machine is the clutch motor. However, the present invention is not limited to this, and the driving device for the sewing machine may be another clutch or motor. Good. Further, it is needless to say that the model of the sewing machine to which the present invention is applied is arbitrary, and other specific detailed structures can be appropriately changed.

[0068]

As described above, according to the driving device for a sewing machine of the present invention, the auxiliary brake that directly brakes and stops the rotating member which is rotatable about the motor shaft and to which the rotation from the auxiliary motor is transmitted. Since the device is used, no impact force due to the rotational inertia of the clutch plate is applied to the rotation transmission part from the auxiliary motor to the rotating member against sudden braking, and the rotation from the auxiliary motor to the rotating member is stopped while the rotation is stopped. It is possible to prevent the play of the transmission portion from being transmitted as play in the rotation direction of the motor pulley.

Since the motor shaft is not freely rotatable by setting the motor lever to the neutral position,
Regardless of the amount of movement of the motor lever and the return spring force of the motor lever, the flywheel provided on the rotor of the main motor or the motor shaft provided with a clutch plate that is brought into pressure contact with the rotating member can be stably rotated freely.

According to the second aspect of the invention, by providing the auxiliary brake device having the spring for holding the rotating member in the braking state, for example, even when a malfunction occurs in the actuator, the spring force of the auxiliary brake spring is applied. Braking performance can be maintained. Therefore, for example, even when the actuator is removed for replacement or repair, the function as the clutch motor can be retained.

Further, when the gear mechanism is used as the rotation transmission device from the auxiliary motor to the rotating member as described in claim 3, the impact force due to the rotational inertia force of the clutch plate is applied to the gear meshing portion against a sudden brake. In addition, the backlash of the gear meshing portion when the rotation is stopped is not transmitted as backlash in the rotation direction of the motor pulley.

Alternatively, in the case where the timing belt device is used as the rotation transmission device from the auxiliary motor to the rotating member as described in claim 4, the clutch plate is provided at the meshing portion of the timing pulley and the timing belt against a sudden brake. The impact force due to the rotational inertia force is not applied,
Further, the play of the meshing portion between the timing pulley and the timing belt while the rotation is stopped and the deflection of the timing belt are not transmitted as the play in the rotation direction of the motor pulley.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view showing a first embodiment of a clutch motor portion to which a driving device for a sewing machine according to the present invention is applied.

FIG. 2 is a schematic vertical sectional view showing a clutch motor portion of a second embodiment to which the invention is applied.

FIG. 3 is a schematic vertical sectional view showing a clutch motor portion of a third embodiment to which the present invention is applied.

FIG. 4 is a schematic vertical cross-sectional view showing an example of a so-called clutch motor as a conventional sewing machine drive device.

FIG. 5 is a schematic front view showing an example of a conventional needle bar fixed position stopping device of a sewing machine.

FIG. 6 is an enlarged view showing details of an actuator section of the stop device shown in FIG.

FIG. 7 is an enlarged view showing details of a switch unit portion of the stop device shown in FIG.

[Explanation of symbols]

 50 clutch motor 51 motor frame 52 main motor rotor 55 flywheel 56 slide sleeve 58 motor shaft 59 motor pulley 61 clutch plate 62 motor lever 64 motor lever return spring 65 rotating member 66 helical gear 67 brake plate 69 timing pulley 71 worm 72 Auxiliary motor shaft 74 Rotation transmission device 75 Auxiliary motor 81 Auxiliary brake device 82 Auxiliary brake pad 84 Auxiliary brake spring 87 Actuator 91 Timing belt 92 Gears 93 Auxiliary motor shaft 94 Rotation transmission device 95 Auxiliary motor 184 Auxiliary brake spring 187 Actuator

Claims (4)

[Claims] 1. A main motor, an auxiliary motor, a motor shaft, a flywheel integrally provided on a rotor of the main motor, and a clutch plate integrally provided on the motor shaft so as to face the flywheel. A rotary member that is free to rotate around the motor shaft on the side opposite to the flywheel with the clutch plate interposed therebetween; a rotation transmission device that transmits the rotation from the auxiliary motor to the rotation member; A motor pulley provided on an outer end portion and a motor lever for moving and operating the motor shaft are provided, and the operation of the motor lever brings the clutch plate into pressure contact with the flywheel or the rotating member to rotate the motor pulley. In a drive device for a sewing machine, which transmits the torque to the main shaft of the sewing machine via a belt, an auxiliary device that directly stops the rotating member to stop the rotation member. Sewing machine drive apparatus comprising the rake device. 2. The driving device for a sewing machine according to claim 1, wherein the auxiliary braking device has a spring that holds the rotating member in a braking state. 3. The drive device for a sewing machine according to claim 1, wherein the rotation transmission device is a gear mechanism interposed between the auxiliary motor shaft and the rotating member. 4. The drive device for the sewing machine according to claim 1, wherein the rotation transmission device is a timing belt device interposed between the auxiliary motor shaft and the rotating member.