JPH07194883A - Driving device of sewing machine - Google Patents

Abstract

PURPOSE:To set the main spindle of a sewing machine to a proper rotating speed according to a sewing work by changing the rotating speed of an auxiliary motor for rotating the main spindle of the sewing machine at low speed according to a change of the pulley diameter in a clutch motor for rotating the main spindle of the sewing machine at high speed. CONSTITUTION:In a driving device of sewing machine, the driving shafts of a clutch motor for rotating the main spindle of a sewing machine at high speed and an auxiliary motor for similarly rotating it at low speed are mutually interlocked and connected. The CPU 801 of a control circuit 800 outputs a control signal to a motor driver 802 for driving the auxiliary motor while it inputs the detection signal from an auxiliary motor starting switch 401. The control circuit 800 has a means for changing the rotation of the auxiliary motor. According to the pulley diameter in the clutch motor, the rotating speed of the auxiliary motor is changed. The rotation changing means may be formed by a dip switch 805. Further, it may be formed by the control by program of the CPU 801.

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 an improvement of a driving device for a sewing machine in which a clutch motor rotates a sewing machine at a high speed and an auxiliary motor rotates a sewing machine at a low speed.

[0002]

2. Description of the Related Art Conventionally, a driving device for this type of sewing machine is disclosed in Japanese Utility Model Laid-Open No. 53-17468. In this sewing machine drive, the auxiliary motor is connected to the main shaft of the sewing machine.

[0003]

However, in the above-mentioned prior art, since the auxiliary motor is connected to the main shaft of the sewing machine, the sewing machine has to be remodeled significantly. Therefore, it is preferable to connect the auxiliary motor to the clutch motor.

An object of the present invention is to provide a driving device for a sewing machine in which the drive shaft of the auxiliary motor is connected to the drive shaft of the clutch motor when the diameter of, for example, a pulley attached to the drive shaft of the clutch motor changes. The reason is that the rotation of the auxiliary motor is changed accordingly.

[0005]

In order to achieve the above object, the present invention is such that the rotation changing means is connected to the auxiliary motor.

[0006]

The rotation changing means changes the rotation of the auxiliary motor.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings.

Referring to FIGS. 1 and 2, there is shown a driving device for a sewing machine according to the present invention. This sewing machine drive device includes a clutch motor 1 and an auxiliary motor 2. The clutch motor 1 rotates the main shaft 4 of the sewing machine 3 at a high speed for normal sewing work, and the auxiliary motor 2 stops the sewing machine needle (not shown) of the sewing machine 3 at an appropriate position. The main spindle 4 is rotated at a low speed.

The clutch motor 1 is attached to the frame means 10, and this frame means is fixed to the lower surface of the table 11 of the sewing machine 3 by any means such as bolts 12 (see FIG. 1).

What should be noted here is that the auxiliary motor 2 is installed separately from the sewing machine 3 or the main shaft 4 of the sewing machine. In the illustrated embodiment, the auxiliary motor 2 is mounted on the casing 20 of the clutch motor 1.
More specifically, for example, a mounting plate 20a is mounted on the casing 20 of the clutch motor, and the mounting plate is fixed to the casing 20 by a screw 20b screwed into a screw hole for a pulley cover of the clutch motor. The clutch motor 1 and the auxiliary motor casing are provided with mounting bolt holes and flanges for mounting these motors at arbitrary positions at the product stage. The motor 2 is fixed to the clutch motor 1. This is convenient because existing holes can be used without special processing of both motors for attaching the auxiliary motor to the clutch motor 1.

The clutch motor 1 is, as shown in FIG.
The rotor 30 serving as a driving body of the motor, the brake shoe 31 fixed in the casing 20 of the clutch motor, and the rotor 30 and the brake shoe 31 are disposed between the rotor 30 and the brake shoe and selectively engage the rotor 30 and the brake shoe 31, respectively. And a clutch plate 32 arranged so as to be compatible with each other. The clutch motor 1 includes a drive device in which the clutch plate 32 engages with the rotor 30, a stop position in which the clutch plate engages with the brake shoe 31, and a neutral position in which the clutch plate does not engage with either the rotor 30 or the brake shoe. Have and. One end of a clutch shaft 33 serving as a drive shaft of the clutch motor is fixed to the clutch plate. The intermediate portion of the clutch shaft rotates with respect to the carrier 34 but does not move in the axial direction.
It is supported on the carrier 34 by 5, 35 '. As shown in FIG. 5, this carrier has a casing 20 of the clutch motor so that the clutch shaft 33 moves in the axial direction thereof to take three positions in the clutch motor, that is, the drive position, the neutral position and the stop position. 5 is supported by a bearing portion 35 provided on the above so as to be slidable in the left-right direction as seen in FIG.

The other end of the clutch shaft 33 projects from the carrier 34. A drive pulley 40 is supported adjacent to the carrier 34 at the other end of the clutch shaft, and adjacent to the drive pulley. A driven sprocket 41 is supported by a one-way clutch 42.

The drive pulley 40 is connected to a driven pulley 43 fixed to the main shaft 4 of the sewing machine via a belt 44. These driving pulley 40 and driven pulley 43
Comprises a V-pulley in the illustrated embodiment, and thus the belt 44 comprises a V-belt.

The driven sprocket 41 is the auxiliary motor 2
Is connected to a drive sprocket 51 fixed to the drive shaft 50, preferably via a timing belt 52. In the illustrated embodiment, the effective diameter of the driven sprocket 41 is set larger than the effective diameter of the driving sprocket 51. This makes it possible to increase the driving torque of the clutch shaft of the auxiliary motor, which is advantageous in terms of cost.

Therefore, when the clutch motor 1 is in the drive position, that is, when the clutch plate 32 is engaged with the rotor 30, the clutch shaft 33 rotates in either direction, and the sewing machine moves through the drive pulley 40 and the belt 44. The spindle 4 of is rotated.

On the other hand, the rotation of the auxiliary motor 2 causes the clutch shaft 33 to rotate in either direction via the drive sprocket 51, the timing belt 52, the driven sprocket 41, and the one-way clutch 42, and the rotation of the clutch shaft 33 is prevented. The main shaft 4 of the sewing machine is rotated via the drive pulley 40, the belt 44, and the driven pulley 43.

Here, it should be noted that the clutch motor 1
Is that the rotation from is not transmitted to the driven sprocket 41 by the one-way clutch 42.

The one-way clutch 42 thus has a function of not transmitting the rotation of the clutch motor 1 to the auxiliary motor side. For example, the bush 60 fitted to the clutch shaft 33 and the outer periphery of the bush 60. And an outer cylinder 61 rotatably fitted in. A driven sprocket 41 is fitted on the outer periphery of the outer cylinder, and both are fixed by appropriate means. As shown in FIG. 6B, a plurality of triangular notch portions 62 arranged at intervals in the circumferential direction are provided on the outer periphery of the bush 60. Therefore, a triangular space including the narrow space 70 and the wide space 71 is formed between the inner circumference of the outer cylinder and the outer circumference of the bush. Rollers 63 are arranged in this space, and each roller is pressed by a spring 64 as shown in FIG. 6B.

It should be noted here that the drive pulley 40, the one-way clutch 42 and the drive sprocket 41 can be attached to the clutch shaft 33 without machining the clutch shaft. Conventionally, the key means 42a is provided on the clutch shaft.
Only the drive pulley was fitted by, and this drive pulley was fixed to the clutch shaft by a nut 42c screwed into a screw 42b provided at the end of the clutch shaft.
In the present invention, the space of the drive pulley 40, the key means, and the screw of the clutch shaft into which the nut is screwed are used (see FIG. 7).

That is, the drive pulley is formed by denting the outer surface of the drive pulley inward to secure a space, and is fitted into the conventional key means of the clutch shaft so as to insert the bush into the recess of the drive pulley. Insert the bush into the clutch shaft. Next, a nut is inserted into the inner hole of the bush, and then the nut is screwed into the screw of the clutch shaft. This nut has a hexagonal head 42d for turning this nut.
Is provided.

In this one-way clutch, as shown in FIG. 6B, when the driven sprocket 41 is rotated by the auxiliary motor 2 in the direction of the arrow D shown by the broken line, the outer cylinder 61 is also rotated in the same direction, and the roller 63 is rotated. Is located in the triangular narrow space 70 shown in FIG. 6B, and therefore rotates the bush 60 together with the outer cylinder 61 in the same direction. This is to rotate the clutch shaft 33 keyed to the bush 60 together with the bush. In conclusion, the rotation of the driven sprocket 41 in the direction of arrow D is to rotate the clutch shaft 33 in the same direction (the direction indicated by the broken line).

In other words, the clutch motor 1
When the clutch shaft 33 is rotated in the direction shown by the broken line in FIG. 6B by the rotation of the bush 6, the bush 60 rotates together with the clutch shaft 33.
3 is located in the wide space 71 against the spring 64, and the rotation of this bush is not transmitted to the outer cylinder 61.

Therefore, the rotation of the clutch motor 1 is not transmitted to the driven sprocket 41.

The auxiliary motor 2 will be described in detail later.
When the clutch rotates, the clutch motor 1 is in the neutral position, that is, the clutch plate 32 is not engaged with either the rotor 30 or the flexure 31.

A clutch lever 100 is provided for moving the clutch plate 32, and thus the carrier 34, such that the clutch motor assumes the drive, neutral and stop positions.

As shown in FIGS. 2 and 5, the clutch lever 100 has a substantially L-shaped configuration as viewed in these figures, that is, a vertical portion 101 and a horizontal portion 102 extending from the vertical portion.
It consists of and. As shown in FIG. 5, the intermediate portion of the vertical portion 101 is connected to the casing 20 of the clutch motor 1 by the shaft 103.
It is rotatably attached to. This clutch motor 1
At one end of the vertical portion 101, for example, the end of the vertical portion 101,
4 is attached. This connecting pin has a head portion 105, which is smoothly fitted into a hole 34a provided in the carrier 34. Therefore, when the other end of the clutch lever 100, that is, the end of the horizontal portion 102 is moved in the direction of the arrow 106 shown by the solid line in FIG. 5, the carrier 34 and the clutch shaft 33 move leftward as viewed in FIG. The plate 32 is moved toward the rotor 30. On the contrary,
When the end of the horizontal portion 102 is moved in the direction of the arrow 107 shown by the broken line in FIG. 5, the carrier 34 and the clutch shaft 33 move to the right as viewed in FIG. 5, and the clutch plate 32 moves toward the brake shoe 31. . FIG. 5 shows a state where the clutch plate 32 is engaged with the brake shoe 31.

Reference numeral 108 denotes a clutch lever return spring, which is attached to rotate the clutch lever 100 so that the clutch lever 100 always engages the clutch plate 32 with the brake shoe 31. It is a force.

A control means is connected to the clutch lever. This control means performs and controls various operations of the sewing machine by selectively rotating either the clutch motor 1 or the auxiliary motor 2 as a whole.

In the illustrated embodiment, this control means has a transmission means 200 connected to the clutch lever and an actuator 201 connected to this transmission means. The actuator 201 comprises a pedal in the illustrated embodiment. As usual, this pedal is rotatably supported by a shaft 201a on, for example, a leg portion of a sewing machine table, and a plurality of front stepped positions, neutral (released) positions and a plurality of forward stepped positions are operated by an operator's foot operation. It is configured so as to take a rear stepping position. In addition, the front stepping means the shaft 201a which is a rotation fulcrum.
It is to step further forward, and to step backward is to step behind the shaft 201a. By pedaling forward or backward, the pedal moves as shown by the broken line in FIG. 2 or as shown by the arrow in FIG.

The transmission means 200 is connected, for example, to a first actuating lever 301 connected to a pedal 201, which is an actuator, via a first connecting rod 300, and to this first operating lever via a connecting lever 302. And a second connecting rod 304 that connects the second operating lever and the clutch lever 100.

It should be noted here that the transmission means 200 is attached to one side surface of one attachment plate 305. This mounting plate is fixed to the casing of the clutch motor 1, for example.

As shown in FIG. 3, the first operating lever 30
One end of No. 1 is rotatably supported on a mounting plate 305 by a shaft 306 serving as a rotation fulcrum, and the other end of the first actuating lever is connected to a pedal 201 via a first connecting rod 300. A shaft 307 is fixed to an intermediate portion of the first actuating lever, specifically, a portion near the other end, and this shaft is fitted in an arcuate slot 308 formed in the mounting plate 305 (FIG. 4). reference). The second operating lever 303 is arranged substantially parallel to the first operating lever 301, and one end of the second operating lever 303 is rotatably supported by a mounting plate 305 by a shaft 309 serving as a rotation fulcrum. This second actuating lever also
A shaft 310 is attached to an intermediate portion thereof, specifically, a portion near the other end, and this shaft is fitted in an arcuate slot 311 formed in a mounting plate 305 (see FIG. 4). Therefore, the first and second actuating levers are rotatable about the respective shafts 306 and 309 in the directions shown by the arrows in FIG. 3 in response to the rotation of the pedals in the directions shown by the arrows in FIG. Is. The first actuating lever and the second actuating lever are connected by a connecting mechanism so that they can move relative to each other by a certain distance. This connecting mechanism is, for example, the connecting lever 30.
One end of 2 is rotatably attached to the second actuating lever 303 by a shaft 312, and a slot 313 extending along the longitudinal direction of the connecting lever is formed at the other end of the connecting lever, and the first lever is provided in the slot. It is formed by fitting a pin 314 fixed to the actuating lever 301. As shown in FIGS. 2 and 3, the first actuating lever 301 and the second actuating lever 303 are made of an elastic material such as a tension spring 315.
Are linked by. One end of the second connecting rod 304 is connected to the other end of the second actuating lever 303,
The other end is connected to the horizontal portion 102 of the clutch lever 100.

As shown in FIG. 2, when the pin 314 is located under the slot 313 of the connecting lever 302, the pedal 210 is stepped forward, that is, the first connecting rod 3
When 00 is pushed down, the first actuating lever 301 pivots downward as seen in FIGS. 2 and 3, and the connecting lever 302
2 is moved downward as viewed in FIG. 2, so that the second actuating lever 303 is rotated downward. The downward rotation of the second operating lever moves the second connecting rod 304 downward, moving the horizontal portion 102 of the clutch lever 100 in the direction indicated by the solid line in FIGS. 2 and 5. As a result, the clutch plate 32 is moved from the position shown in FIG.
Strictly speaking, it means moving toward the neutral position. As shown in FIG. 1, a cover 350 that covers the various components mounted on the mounting plate 305 is fixed to the mounting plate.

The detailed operation of the above apparatus will be described later.

The control means also includes auxiliary motor switching means 400 for starting the auxiliary motor 2 and clutch motor switching means 500 for starting the clutch motor 1.
A needle position setting means 600 for setting the sewing needle at an arbitrary position, a thread trimming starting means 700, and a control rotation 80.
0 (FIG. 7).

The auxiliary motor switching means 400 includes an auxiliary motor starting switch 401 in the illustrated embodiment. As shown in FIGS. 2 and 3, the tip of the movable contact piece 401a of the auxiliary motor starting switch 401 is turned on or off according to the movement of the first operating lever 301.
Are arranged to be done. The auxiliary motor starting switch 401 is fixed to the mounting plate 305.

The clutch motor switching means 500 includes a synchronizer 501, which is provided on the main shaft 4 of the sewing machine adjacent to the driven pulley 43, as shown in FIG. This synchronizer can detect the speed and needle position of the sewing machine.

As shown in FIGS. 2 to 4, the needle position setting means 600 includes a neutral actuator 601 and a first needle position switch 602, and the thread trimming activation means 700 includes a second needle position switch 603. And the safety actuator 60
4 and. These neutral actuators 601,
As shown in FIG. 4, the first and second needle position switches 602 and 603 and the safety actuator 604 are fixed to the surface of the mounting plate 305 opposite to the transmission means 200.

Drive shaft 601 of neutral actuator 601
One end of a neutral lever 605 is attached to a, and the other end of the neutral lever penetrates a hole 606 provided in the attachment plate and is arranged to face the upper edge 607 of the second actuating lever (Fig. 3 and FIG. 4). The neutral lever 605 is rotatably supported by the mounting plate 305 via a shaft 608. When this neutral actuator is activated, that is, when its drive shaft 601a is contracted from the state shown in FIG. 4,
The other end of the neutral lever rotates so that the second actuating lever 303 is pushed downward. The reference numeral 609 indicates the shaft 608.
Shows the return spring mounted on. The tip of the movable contact piece 602a of the first needle position switch 602 is arranged to face the upper edge of the first actuating lever 301 as shown in FIG.

The safety actuator 604 is provided with a safety pin 610 fixed to the tip of the drive shaft 604a so as to extend in a direction substantially perpendicular to the longitudinal direction of the drive shaft. One end of the safety pin 610 has a mounting plate 305.
It is arranged so that it can be located on the lower surface of the projecting piece 612 provided in the intermediate portion of the first actuating lever 301 by penetrating the elongated hole 611. Therefore, the safety actuator 6
When 04 has its drive shaft 604a retracted from the extended position shown in FIG. 4 to the retracted position, the safety pin 610 is placed on the lower surface of the projecting piece 612 of the first actuating lever 301, the first actuating lever 301 at this time. Is restricted from rotating downward.

Reference numeral 613 indicates the safety actuator 60.
4 shows a return spring provided on the No. 4 drive shaft 604a. The thread cutting means 700 has a thread cutting solenoid 700a (FIG. 7) and a thread cutting click 701. The thread cutting solenoid has the usual form of operating a thread cutting cutter. As shown in FIG. 4, the thread trimming click 701 has a substantially U-shaped lever 703 rotatably attached to a mounting plate 305 by a shaft 702, and one end of this lever is a hole provided in the mounting plate 305. A first arm 70 extending through 704
5, the tip of this arm has a first actuating lever 301
Is disposed so as to face the upper edge (see FIG. 3). Lever 70
3 also has a second arm 706, which faces the movable contact 707 of the second needle position switch 602.

A block diagram of the control circuit 800 is shown in FIG. This control circuit includes a CPU 801, a motor driver 802 connected to the CPU, and a CPU.
And a solenoid driver 803 connected to the. The motor driver 802 controls the auxiliary motor 2, and the solenoid driver 803 restricts the thread cutting solenoid.

CPU 801, auxiliary motor starting switch 401, first and second needle position switches 602, 60
The connection state with 3 and the like is as shown in FIG.

It should be noted that the rotation changing means 805 for changing the rotation of the auxiliary motor is provided. In a sewing machine using a clutch motor, when changing the rotation of the main shaft of the sewing machine depending on the sewing purpose, the diameter of the pulley of the clutch motor is usually changed. As a result, when the drive of the auxiliary motor is transmitted to the drive shaft of the clutch motor, the rotation of the main shaft of the sewing machine by the auxiliary motor changes. Therefore, the purpose of the rotation changing means is to electrically control the rotation of the auxiliary motor in accordance with the conversion of the pulley of the clutch motor. Although this rotation changing means is composed of the DIP switch 806 in the illustrated embodiment, it is shown in FIG. 8 but can be controlled by the program of the CPU 801.

The operation of the sewing machine drive device will be described below for each working mode of the sewing machine according to the pedal operation.

First Pedaling of Pedal From the state shown in FIG. 2 and FIG. 5, when the pedal is firstly depressed, that is, when the pedal is slightly depressed from the neutral position of the pedal, the transmission means 200 is actuated. As described above, the first operating lever 301 is pivoted downward via the first connecting rod 300, and the clutch lever 100 is moved via the connecting lever 302, the second operating lever 303, and the second connecting rod 304. The horizontal part 102 is moved downward (in the direction of the arrow indicated by the solid line in FIG. 5). Therefore, the clutch plate 32 changes from the stop position shown in FIG. 5 to the neutral position (half clutch). At this time, the main shaft 4 of the sewing machine is manually rotatable. In this case, the auxiliary motor starting switch 401 has not been turned on yet.

Second front depression of the pedal When the pedal is further forward depressed from the first front depression of the pedal, the auxiliary motor starting switch 401 is turned on, the auxiliary motor 2 rotates, and the main shaft of the sewing machine rotates at a low speed.

FIG. 9 shows a flow chart for low speed sewing.

When the third front depressing of the pedal is further performed from the second front depressing to the third front depressing, the transmission means 200 further operates in the direction described in the first front depressing, and the clutch plate 32 is a drive position, that is, the rotor 3
It moves so that it is pressed against 0. Therefore, the rotation of the clutch motor is transmitted to the main shaft 4 of the sewing machine via the clutch shaft 33, the driving pulley 40, the belt 44 and the driven pulley 43, and the sewing machine rotates at high speed. This high-speed rotation of the sewing machine is used for performing a normal sewing operation of the sewing machine.

When the high-speed rotation of the sewing machine exceeds a predetermined speed, this is detected by the synchronizer 501 and the rotation of the auxiliary motor is stopped. The auxiliary motor sets the speed of the spindle at a predetermined speed or more, for example, about 300 RPM or less, for example, about 170 RPM. This can reduce the power consumption of the auxiliary motor and increase its life.

When the rear pedal is depressed from the third front pedal to the rear position to move the pedal to the neutral position (release position), the first connecting rod 300 moves upward and the first actuating lever 301 rotates upward. Move.
At this time, the upward rotation of the first operating lever is not immediately transmitted to the second operating lever 303. This is due to the slot 313 provided at the other end of the connecting lever 302. That is, the second actuating lever 303 is lifted upward only when the upward movement of the first actuating lever 301 exceeds the length of the slot 313. The tension spring 315 is tensioned as the first actuating lever is moving within the slot of the continuous lever.

When the second actuating lever 303 moves upward, the second connecting rod 304 moves upward, and the horizontal portion 102 of the clutch lever 100 moves upward when viewed in FIG. Accordingly, the clutch plate 32 moves to the right in FIG. 5 due to the biasing force of the clutch lever return spring 108, and this clutch plate 32 is moved to the brake shoe 3
1 (press position of the clutch motor), and the clutch motor 1 is stopped.

In this state, the sewing needle takes an unstable stop position.

When the pedal is first depressed from the neutral position to the first depressed state, the first connecting rod 300 moves upward, and accordingly,
The first operating lever 301 rotates upward. As a result, the upper edge of the first actuating lever 301 is connected to the movable contact piece 602a of the first needle position switch 602, and this switch is turned on. At this time, the synchronizer 501 confirms the needle position, and when it is not under the needle, the neutral actuator 601 is activated. More specifically, when the drive shaft 601a of the neutral actuator 601 is contracted, the neutral lever 605 is actuated, and the second actuating lever 303 is rotated downward (pushed down). In this case, the second actuating lever 303
The downward rotation of
Is not transmitted to the first actuating lever 301. The downward rotation of this second actuating lever 303 pushes down on the second connecting rod 304, and thus the clutch lever 10
The horizontal part 102 of 0 is pushed down, the clutch plate 32 is moved to the left from the state shown in FIG. 5, and the clutch motor is set to the neutral position.

When the clutch motor is in the neutral position,
The auxiliary motor 2 is rotated to rotate the main shaft 4 of the sewing machine at a low speed. Next, the synchronizer 501 detects the needle position and generates a needle down signal when the needle reaches the needle down position. This needle down signal makes the neutral actuator 601 and the auxiliary motor 2 inoperative (OFF). Then, the neutral lever 605 is returned to the original position by the return spring 609 and does not restrain the second actuating lever 303, so that the second actuating lever 303 is rotated upward by the tension spring 315.
As a result, the second connecting rod 304 is moved upward and the horizontal portion 102 of the clutch lever 100 is pushed up.
Therefore, the clutch plate 32 is moved to the right as viewed in FIG. 5, and this clutch plate is pressed against the brake shoe 31. In this way, the clutch plate 32 is pressed against the brake shoe 31 and stopped by utilizing the acting force of the clutch lever return spring 108 and the tension spring 315. The clutch lever return spring 10 is used to press the clutch plate against the brake shoe.
It should be noted that the acting force of the No. 8 and the tension spring 315 is applied. In such a state, the clutch shaft 33 is fixed, and the rotation of the main shaft of the sewing machine and the auxiliary motor 2 is stopped.

In this way, in the first rear depression of this pedal, the main shaft of the sewing machine is rotated at a low speed by the auxiliary motor, and the auxiliary motor is stopped at the needle down position of the sewing machine needle. Can be stopped at. Further, the sewing machine needle can be stopped at the needle up position as described above by the vertical position selection switch 806 shown in FIG.

Pedal second rear depressing When the pedal is depressed to the second stage from the pedal third depressing state (high-speed rotation of the sewing machine) to the pedal second rear depressing state,
The first actuating lever 30 via the first connecting rod 300.
1 is turned up, the first needle position switch 602 is turned on, and the first arm 705 of the thread trimming click 701 is lifted up. This means that the second arm 706 of the thread trimming click 701 is pushed downward (see FIG. 4) to move the movable contact 70 of the second needle position switch 602.
7 is pressed and this second needle position switch is turned on.
Let

It should be noted that the control circuit 800 activates the safety actuator 604, that is, causes the drive shaft 604a of the safety actuator to contract against the return spring 613, and the safety pin 610 causes the first actuating lever 301 to move. Is provided on the lower surface of the protruding piece 612. As a result,
The downward rotation of the first operating lever is blocked. In other words, the first actuating lever is prevented from being pushed down by the inadvertent forward depression of the pedal, and the pedal returns to maintain a certain acting force on the elastic body 315. Thus, the clutch plate can be pressed against the brake shoe.

When the safety actuator 604 is activated, the synchronizer 501 generates a needle down signal. When the needle down signal is generated, first, the neutral actuator 601 is activated, that is, the drive shaft 60 of the neutral actuator 601 is activated.
When 1a is contracted, the neutral lever 605 is actuated and the end thereof is rotated so as to push down the second actuating lever 303. In this case, the downward rotation of the second operating lever 303 is not transmitted to the first operating lever 301 by the slot 313 of the connecting lever 302. The downward rotation of the second actuating lever 303 pushes down the second connecting rod 304, and thus pushes down the horizontal portion 102 of the clutch lever 100 to move the clutch plate 32 to the left from the state shown in FIG. , Set the clutch motor 1 to the neutral position.

When the clutch motor 1 is in the neutral position, the auxiliary motor 2 is rotated and the main shaft 4 of the sewing machine is rotated at a low speed. Next, the synchronizer 501 detects the needle position and generates a needle down signal when the needle takes the needle down position.
The control circuit activates the thread cutting solenoid by the generation of the needle down signal and causes the thread cutting cutter to cut the thread. Therefore, thread cutting can be performed while the sewing machine is rotating at a low speed. After the thread cutting, the synchronizer 501 detects the needle up position of the needle and generates the needle up signal. In response to the generation of the needle up signal, the control circuit firstly stops the main shaft of the sewing machine in the needle up state, and secondly, inactivates (turns off) the thread cutting solenoid, for example, after 20 mSEC (timer). State), and thirdly, the safety actuator 604, for example, after 60 mSEC (timer),
Disable it.

The details of stopping the main shaft of the first sewing machine in the needle up state are as follows.

When the needle up signal is issued, the neutral actuator 601 and the auxiliary motor 2 are inoperative, that is, the drive shaft 601a of the neutral actuator is extended by the return spring 609, and as a result, the neutral lever 605 has the second end at the second end. Is rotated away from the operating lever 303.
Then, the second operating lever 303 causes the tension spring 315 to move.
Of the clutch lever 100 is lifted upward by the force of the second coupling rod 304, and thus the clutch plate 32 is moved to the right as viewed in FIG. 5, as described above. The brake shoe 31 with pressure. The pressure force of the clutch lever return spring 108 and the tension spring 315 is applied to the pressure contact of the brake shoe of the clutch plate. As a result, the auxiliary motor is stopped and the sewing machine can be stopped on the needle. Next, by returning the pedal to the neutral position, the first operating lever 301 rotates downward, and the thread trimming click 701 returns to the original position.

FIG. 10 shows a flowchart for stopping the needle at the upper and lower positions, and FIG. 11 shows a flowchart for performing thread cutting.

FIG. 12 shows a second embodiment of the present invention, and FIG.
3 shows the third embodiment of the present invention, and FIGS. 14 and 15 show the fourth embodiment of the present invention. In these drawings, parts similar to those of the above-described first embodiment of the present invention are indicated by like reference numerals with dashes.

In the second embodiment shown in FIG. 12, as compared with the first embodiment, the first operating lever 301 is located below the second operating lever 303 'and the elastic body 315' is arranged on the rod 9 side.
00, the rod has its lower end fixed to the upper edge of the first actuating lever 301 'and its upper end loosely fitted into a hole 901 provided in the lower edge of the second actuating lever 303'. It is different in that it is done.

In the second embodiment shown in FIG. 13, as compared with the first embodiment, the first operating lever 301 'and the second operating lever 303' are combined together by one supporting shaft 902 serving as one supporting point. They differ in that they are rotatably supported.

In the fourth embodiment shown in FIGS. 14 and 15, as compared with the first embodiment, the first operating lever 301 'and the second operating lever 303' are moved vertically as shown in FIG. One support lever 903 that is arranged in an overlapping manner and that these first and second actuating levers are arranged in a substantially horizontal direction.
It is different in that it is supported at one end.

The other end of the support lever 903 is rotatably attached to the attachment plate 305 by a shaft 904.

An upper slot 905 and a lower slot 906 are provided at both ends of the first actuating lever 301 '.

The lower end of the second actuating lever 303 'has a hole 907 facing the lower slot 906 of the first actuating lever.
Is provided. Also, this second actuating lever has a hole 9
A slot 908 is provided above 07 and opposite the upper slot 905 of the first actuating lever. A first bolt 909 is inserted into the upper slot 905 of the first actuating lever and the slot 908 of the second actuating lever, and into the lower slot 906 of the first actuating lever and the hole 907 of the second actuating lever. Has a second bolt 910 inserted therein.

These first and second bolts 909, 9
Nuts 911 and 912 are respectively screwed into 10 to hold the first and second actuating levers in a state in which they are movably overlapped with each other, as shown in FIG.

A tension spring 315 'is attached to the first and second bolts 909 and 910 to connect them.

These second to fourth embodiments also operate in the same manner as the first embodiment.

It should be noted that the present invention is not limited to the above-mentioned first to fourth embodiments, and various modifications can be made.

In the present invention, the driving force of the clutch motor is transmitted to the main shaft of the sewing machine by the pulley assembly, and the driving force of the auxiliary motor is transmitted to the main shaft of the sewing machine by the sprocket assembly. It should be noted that the present invention is not limited to the sprocket assembly and other means such as a gear assembly can be used instead.

[0076]

According to the present invention, since the rotation changing means of the auxiliary motor is provided, the rotation speed of the auxiliary motor can be changed in accordance with the change in the pulley diameter of the clutch motor. There is a real advantage that it can be set to an appropriate number of rotations according to the sewing work.

[Brief description of drawings]

FIG. 1 is a perspective view of a sewing machine to which an embodiment of a driving device for a sewing machine according to the present invention is applied.

FIG. 2 is a schematic partial cross-sectional view of a driving device for a sewing machine according to the present invention.

FIG. 3 is a perspective view mainly showing a transmission means from one side of a driving device for a sewing machine according to the present invention.

FIG. 4 is a perspective view similar to FIG. 3, showing the transmission means from the other side.

FIG. 5 is a side view showing a part of a clutch motor and an auxiliary motor in partial cross section.

FIG. 6A is a front view showing a connected state of a clutch motor and an auxiliary motor, and FIG. 6B is a partially enlarged view of a one-way clutch motor.

FIG. 7 is an enlarged cross-sectional view of a unidirectional clutch portion.

FIG. 8 is a block diagram showing a connection state between a control unit and an auxiliary motor or the like.

FIG. 9 is a flowchart when low-speed sewing is performed by the sewing machine drive device of the present invention.

FIG. 10 is a flow chart in the case where the sewing machine driving device according to the present invention stops the sewing machine needle in the vertical position.

FIG. 11 is a flowchart when thread cutting is performed by the sewing machine driving device of the present invention.

FIG. 12 is a perspective view similar to FIG. 3, showing a second embodiment of the present invention.

FIG. 13 is a perspective view similar to FIG. 3, showing a third embodiment of the present invention.

FIG. 14 is a perspective view similar to FIG. 3, showing a fourth embodiment of the present invention.

15 is a cross-sectional view showing a connected state of the first and second actuating levers of FIG.

[Explanation of symbols]

 1: Clutch motor 2: Auxiliary motor 4: Main shaft of sewing machine 20: Casing of clutch motor 30: Rotor 31: Brake shoe 32: Clutch plate 33: Clutch shaft 34: Carrier 40: Drive pulley 41: Driven sprocket 42: One direction Clutch 43: Driven pulley 51: Drive sprocket 100: Clutch lever 200: Transmission means 201: Actuator (pedal) 301: First operating lever 303: Second operating lever 305: Mounting plate 400: Auxiliary motor switching means 500: Clutch motor switching means 600: Needle position setting means 700: Thread trimming activation means 800: Control circuit

Claims (3)

[Claims] 1. A sewing machine drive device in which a drive shaft of a clutch motor for rotating the sewing machine at a high speed and a drive shaft of an auxiliary motor for rotating the sewing machine at a low speed are operatively connected to each other, and rotation changing means for changing the rotation of the auxiliary motor. A drive device for a sewing machine, characterized by being provided with. 2. The driving device for a sewing machine according to claim 1, wherein the rotation changing means comprises a DIP switch connected to an auxiliary motor. 3. The driving device for the sewing machine according to claim 1, wherein the rotation changing means comprises a CPU connected to an auxiliary motor.