JPH0221834B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a cycle sewing machine that uses a cam plate according to the sewing pattern to repeatedly execute the same sewing pattern. This relates to a stopping device.

[Prior Art] FIGS. 4 to 6 are diagrams showing a conventional cycle sewing machine and a drive stop device built therein.

In the figure, 1 is a motor as a driving means,
The driving force is transmitted to the drive pulley 4 via the motor pulley 2 and the V-belt 3. Further, the drive pulley 4 is movable in the left and right direction,
When moving to the left, it is connected to the drive clutch 5,
An upper shaft 6 fixed to the center of this drive clutch 5
The driving force from the motor is transmitted to the motor. A cam plate 7 is connected to the upper shaft 6 through gears 8, 9, 10 and a drive shaft 11. A cam groove 7a is formed on the upper surface of the cam plate 7, and a flat low-speed notch 12 and an end portion are formed on the lower surface of the cam plate. A blocking notch 13 having an inclined stepped portion 13a is provided in a protruding manner. 1
Reference numeral 4 denotes a fabric conveyance member that moves over the sewing machine bed MB along the cam groove 7a of the cam plate 7, and conveys the fabric while pressing it with a presser foot (not shown) provided at the tip. 15 is a control device consisting of a CPU 15a and a ROM 16b, and switches S ₁ and S ₂ are ON and OFF.
In the case of , motor 1 is driven at high speed, switches S ₁ and S ₂
is OFF, low speed drive when ON, switch S ₁ ,
It is designed to stop when S ₂ is OFF or OFF. Reference numeral 16 denotes a starting switch that is turned ON and OFF by pressing and releasing the foot pedal 17, and the CPU 15a activates the starting magnet 18 according to the output signal of the switch.
The rod 18a is raised and lowered.
19 is a starting lever connected to the rod 18a of the starting magnet 18 via a chain 20;
It is normally biased counterclockwise in FIG. 4 by the spring 21, and rotates clockwise against the spring 20 as the rod 18a descends. Reference numeral 22 denotes a cutoff frame which is rotatably held on the side of the sewing machine main body M, and is always biased clockwise in FIG. 4 by a spring 23. A locking portion 22a that engages with a groove formed on the side surface of the drive clutch 5.
are formed, and step-like locking steps 22b ₁ and 22b ₂ are formed at the lower end. 24 is a switch operating plate protruding from the cutoff frame 22;
The movement of the cutoff frame 21 activates the microswitches S ₁ and S ₂ . 25 is a clutch lifter that rotates together with the cutoff frame 22 and brings the drive pulley 4 into and out of contact with the drive clutch 5;
6 to the blocking frame 22.
Reference numeral 27 denotes a hook release lever as a locking member rotatably supported by the sewing machine main body M, and is urged counterclockwise in FIG. 4 by a spring 28 so that one end 27a comes into contact with the lower surface of the cam plate 7. A locking pawl 27b that engages with the locking step portion 21b ₁ or 21b ₂ is provided at the other end of the lever 27. In addition, 29 is a knife that cuts the thread at the end of sewing.

The conventional cycle sewing machine and its drive device are constructed as described above, and in the initial state when the power is turned on, the starting switch 16 is OFF, so the rod 18a of the starting magnet 18 is turned off.
is on the rise. For this reason, the blocking frame 22
The upper shaft 6 is rotated counterclockwise by the spring 21, and its upper end 22a is engaged with the drive clutch 5 to fix the rotational position of the upper shaft 6. At this time, the motor 1 is being driven at low speed because the switch operating plate 24 presses S ₁ to turn it on, but the clutch lifter 25 rotates to the left together with the cutoff frame 22 to move the drive pulley 3 away from the drive clutch 5. Since they are separated, the driving force of the motor 1 is not transmitted to the upper shaft.
Therefore, the cam plate 7 is held at the sewing starting position, and in this state, one end 27a of the hook release lever 27 is in contact with the rear end of the inclined stepped portion 13a of the cutoff notch 13.

Now, when the foot pedal 17 is depressed and the starting magnet 18 is turned on, the rod 18a of the starting magnet 18 descends, the starting link 19 rotates clockwise, and the cutoff frame 22 rotates counterclockwise. As a result, the upper end 27a of the cutoff frame 22 is separated from the drive clutch 5, and the micro switches S ₁ and S ₂ are activated by the switch actuating plate 24.
The motor 1 is turned on and off to drive the motor 1 at high speed, and the clutch lifter 25 connects the drive pulley 3 and the drive clutch 5, causing the upper shaft 6 to rotate and the cam plate 7 to rotate in the direction of arrow a. When the cam plate 7 starts rotating, one end 27 of the hook release lever 27
a comes off from the blocking notch 13 and comes into contact with the lower surface of the cam plate 7, and the locking pawl descends and moves to the first stage,
It engages with the locking stepped portion _21b1 of the cutoff frame 22 to hold the cutoff frame 22 against the spring 23 (see FIG. 6a). Therefore, even if the pressure on the pedal 17 is released and the activation lever 19 is returned to the initial position, the cutoff frame 22 does not change from the first position. In addition, the rotation of the cam plate 7 causes the cloth conveying member 1 to
4 moves along the groove 7a of the cam plate 7 and conveys the cloth, and stitches are formed by the needle moved up and down by the upper shaft 6.

When the end of one sewing cycle approaches, the hook release lever 2 that was in contact with the lower surface of the cam plate 7 is released.
7 rides on the low speed notch 12 and moves to the second stage (see Figure 6b). As a result, the locking claw 27b
rises and disengages from the locking step 12b ₁ , the blocking frame 22 is slightly rotated counterclockwise by the spring 23, and the locking step _21b2 engages with the locking pawl 27. This slight rotation of the cutoff frame 22 turns the microswitches S ₁ and S ₂ OFF and OFF, and the motor 1 is driven at a low speed. Thereafter, due to the rotation of the cam plate 7, the one end 27a of the hook release lever 27 rides on the inclined stepped part 13a from the flat plate part 13b of the blocking notch 13, and the locking pawl 27b further rises and moves to the third stage (the third stage). (see Fig. 6c), it comes off the inclined step part 13. As a result, the cutoff frame 22 is rotated clockwise by the spring 23, and the microswitches S ₁ and S ₂
turns OFF and ON, and motor 1 stops driving. At the same time, the drive pulley 4 separates from the drive clutch 5, cutting off the transmission of the driving force to the upper shaft 6, and the upper end 22a of the cutoff frame 22 fits into the groove of the drive clutch 5, causing the upper shaft 6 in place.

With the above steps, one cycle of sewing operation is completed.

[Problems to be Solved by the Invention] As described above, in the conventional cycle sewing machine, when the pedal 17 is operated normally, that is, when the pedal 17 is immediately released after being depressed, the motor 1 is Since the stop occurs after going from a high speed stage to a low speed stage, the upper end 22a of the cutoff frame 22 and the drive clutch 5 can be fitted together with almost no impact. It is easy to make operational errors such as depressing the pedal 17 again during the sewing process or forgetting to release the pedal 17 after it has been pressed, and in such cases, the pedal 17 is often released in a hurry just before the end of the sewing operation.

If such an operation error occurs, the locking pawl 27b of the hook release lever 27 has moved upward to the third stage due to contact between the one end 27a and the inclined stepped portion 13a. Due to the release, the cutoff frame 22 fits into the groove of the drive clutch 5 rotating at high speed, and when fitted, both members 2
An extremely large load was applied to 2 and 5 and surrounding members, causing problems such as damage to the device.

This invention was made by focusing on the above-mentioned problem, and even if the operator makes a mistake in pedal operation, the drive will definitely be in a low-speed drive state before the drive stops, and a large load will be applied when the upper shaft is stopped by the cutoff frame. An object of the present invention is to provide a drive stop device for a cycle sewing machine that can prevent the above.

[Means for Solving the Problems] The present invention provides a pedal that is held detachably from the upper shaft, is always biased to engage with the upper shaft, and is pressed when a pedal that supports stopping the driving of the sewing machine is pressed. A blocking frame that moves to a non-engaging position with the upper shaft; and a cam plate that rotates together with the upper shaft sequentially moves to first, second, and third stages during one sewing cycle according to the rotational position of the cam plate that rotates with the upper shaft; 1. A control means for holding the cutoff frame at a different non-engaging position with the upper shaft in a second stage and stopping driving of the driving means in a third stage, and moving in three stages together with the locking member. It is possible and
a second locking member that locks the cutoff frame together with the locking member in the first and second stages; a second locking member that is movable in response to pressing and releasing the pedal; The second located in the stage
and a holding member that engages with the engaging member and maintains their positions with respect to each other.

[Function] In this invention, when the operator performs a normal pedal operation, the holding member moves as the pedal is pressed, but since the locking member locks the cutoff frame in the first stage, It returns to its original position simultaneously with the release of the pedal without engaging the locking member.
Thereafter, the locking member moves to the second stage as the cam rotates, and the blocking frame also moves accordingly. This causes the motor to drive at low speed and then stop.
The cutoff frame can stop the upper shaft with almost no load on surrounding members.

In addition, if the operator makes a mistake in operation and presses the pedal until just before the end of sewing, the holding member will remain moved from the initial position during that time, and the second locking member will move from the first stage. When it moves to the second stage, it engages with the holding member and mutually maintains its position. Therefore, even if the pedal is subsequently released just before the end of sewing, the second locking member will keep the cutoff frame in the second position. It is held in the locked position and the motor is driven at low speed. Therefore, after this, if the engagement between the second locking member and the holding member is released as appropriate, the cutoff frame will fit quietly into the upper shaft, and no excessive load will be applied.

[Embodiment of the Invention] An embodiment of the invention will be described below with reference to FIGS. 1 to 3.
This will be explained based on the diagram. Note that the same or equivalent parts as in the conventional example are given the same reference numerals, and detailed explanation thereof will be omitted.

In the figure, 30 is a safety lever as a second locking member connected to the side surface of the hook release lever 27 (first locking member) so as to be rotatable about a fulcrum 30c. Long hole 30 forming a shape
a is formed, and a locking screw 31 protruding from the hook release lever 27 is inserted into the elongated hole 30a. Further, a spring 32 is installed between the safety lever 30 and the hook release lever 27, and this spring 32 causes the safety lever 30 to
is biased in the direction of arrow e (see FIG. 1) and is always held at a position where the lower end of the elongated hole 30a abuts against the locking screw 31.

Reference numeral 33 denotes a release lever rotatably connected to the other side of the hook release lever 27 about a fulcrum 34, whose tip end 33a is always in contact with the activation lever 19 due to its own weight, and whose rear end is in contact with the activation lever 19. By pressing the provided operating part 33b downward, the other end 33a moves upward, and the locking end 30b of the safety lever 30 is pushed upward. 35 is a stepped portion 1 formed on the activation lever 19
The safety arm 35 is rotatably inserted through the outer periphery of the safety arm 9A, and the safety arm 35 is biased in the direction of arrow b in FIG. 1 by a coiled spring 36.

37 is a movable arm rotatably inserted through the outer periphery of the stepped portion 19A, and this movable arm 37 is connected to the coil spring 3.
8 in the direction opposite to the safety arm 35 (in the direction of arrow c), and the bent portion 37a is in contact with one side of the safety arm 35. Further, one end of the coil spring 38 is hooked to a pin 39 fixed to the activation lever 27, so that the movable arm 37 rotates via the coil spring 38 as the activation lever 19 rotates. It's summery. When the rod 18a of the starting magnet 18 is raised, the force applied to the safety arm 35 by the coiled spring 36 is greater than the force applied to the movable arm 37 by the coiled spring 38. Note that the other configurations are the same as those of the conventional example.

Based on the above configuration, the operation will be explained next.

When the pedal 17 is depressed and the start switch 16 is actuated, the start lever 19 is rotated in the direction of arrow d by the rod 18a of the start magnet 18, as in the conventional case, and the cutoff frame 22 is rotated. At the same time as the fitting is released, the motor 1 is driven at high speed, and the driving force is transmitted to the upper shaft 6 to rotate the cam plate 7.

At this time, the rotation of the starting lever 19 causes the pin 3 to
The biasing force of the coiled spring 38 locked to 9 increases,
The movable arm 37, together with the safety arm 35 in contact with it, is rotating in the direction of arrow c against the coil spring 36 (see FIG. 3a).

During normal operation of the pedal 17, the pressure on the pedal 17 is released at the same time as the drive of the motor 1 starts, so the movable arm 37 and the safety arm 35 are moved to the activation lever 1.
9, rotates in the b direction and returns to the initial position.

When the sewing operation approaches the end, the hook release lever 27 is moved to the second and third stages by the low speed notch 12 and cutoff notch 12 of the cam plate 7.
Accordingly, the cutoff frame 22 sequentially moves to drive the motor 1 at a low speed and then stop it. At this time, the safety lever 30 is moved together with the hook release lever 27 by the locking screw 31 and the spring 32.
In the first and second stages, the hook portion 30c
together with the locking pawl 27b of the release lever 27, are sequentially engaged with the locking step portions 21b ₁ and 21b ₂ .

In addition, the operator presses the pedal 1 until just before the end of the sewing operation.
7 continues to be pressed, the motor 1 continues to drive at high speed because the cutoff frame 22 is rotated and held in the direction of the arrow f by the activation lever 19 during that time. Further, by pressing the pedal 17, the safety arm 35 and the movable arm 37 are held while being rotated in the direction of arrow c together with the activation lever 19.

Then, when the cam plate 7 rotates and the sewing operation approaches the end, the hook release lever 27 and the safety lever 30 move from the first stage to the second stage, and the safety lever 30 comes into contact with the lower surface of the safety arm 35. contact,
Both parts 30, 35 maintain their position relative to each other by contact friction (see FIG. 3b). In addition, in this state, the safety lever 30 and the hook release lever 27 are
are not engaged with the locking steps 21b ₁ and 21b ₂ of the cutoff frame 22.

After that, when the one end 17a of the hook release lever 27 rides on the inclined part 13b of the cutoff notch 13,
The locking pawl 27b rises and moves to the third stage.

At this time, since one cycle of sewing operation is completed, the worker realizes that he had forgotten to release the pedal until then, and releases the pedal 17 in a hurry. In this case, in the conventional device, the cutoff frame 2
Since the locking pawl 27b that locks the clutch 2 has moved to the third stage, the cutoff frame 22 is returned to its initial position by the spring 23, and is engaged with the drive clutch 5 that was rotating at high speed, thereby shutting down the device. This resulted in an overload.

but. In this embodiment, even if the locking pawl 27b moves to the third stage, the safety lever 30 abuts the safety arm 35 and is held at the second stage, so the spring 23 The cutoff frame 22 that moves toward the position touches the safety lever 3 on the way.
It is locked at 0. For this reason, the micro switch
S ₁ and S ₂ are turned OFF and OFF, and the motor 1 is switched from high-speed drive to low-speed drive, and thereafter, the second sewing cycle is performed at low-speed drive. After this, when the operator pushes the operation part 33b of the release lever 33 downward, the tip 33a of the release lever 33 pushes up the safety lever 30, so the engagement state between the safety lever 30 and the safety arm 35 is released, and the safety arm 35
is returned to its initial position by the coiled spring 36, and the safety lever 30 moves upward together with the unhooking lever 27. As a result, the isolation frame 22
3 to the initial position, and is engaged with the drive clutch 5 rotating at a low speed to hold the upper shaft 6 at the initial position.

In this way, the cutoff frame 22 is fitted into the drive clutch 5 rotating at a low speed, so that no large load is applied during the fitting.

In addition, in the above embodiment, the release lever 23
The engagement between the safety lever 30 and the safety arm 35 is released by manually operating the safety lever 30, but the cam plate 7 is provided with a notch for disengaging the engagement, and the release lever 33 is automatically operated. It is also possible to do so.

[Effects of the Invention] As explained above, according to the present invention, in any case, the sewing machine can be stopped after passing through the low-speed driving state, so that a large load is applied when the cutoff frame and the upper shaft are fitted together. Without a doubt,
This has the effect of significantly improving the lifespan and safety of the device.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is an exploded perspective view of a main part of the device shown in Fig. 1, and Figs. 3 a, b, and c are operating states of the device shown in Fig. 1. 4 is a side view showing a conventional cycle sewing machine and its drive stop device, FIG. 5 is a perspective view of the main part of the machine shown in FIG. 4, and FIGS. 6 a, b,
FIG. 5c is a side view showing the engaged state of the hook release lever and the locking stepped portion shown in FIG. 5; 1...Motor (driving means), 6...Upper shaft, 7...
...Cam plate, 14...Fabric conveyance member, 15...Control device (control means), 17...Pedal, 27...Hook release lever (first locking member), 30...Safety lever (second locking member), 35...safety arm (holding member).

Claims (1)

[Scope of Claims] 1. A cloth conveyance member is moved along a groove formed in a cam plate that rotates in conjunction with the upper shaft, and a predetermined sewing pattern is formed by the needle that moves up and down by the upper shaft. A drive stop device for a cycle sewing machine configured to drive and stop the drive means by pressing and releasing a predetermined pedal, and to lock the upper shaft at a predetermined position when the drive means is stopped. a cutoff frame that is held detachably from the upper shaft, is normally biased to engage the upper shaft, and moves to a position in which the upper shaft is not engaged when the pedal is pressed; , The cam plate sequentially moves to three stages, first, second, and third, during one sewing cycle according to the rotational position of the cam plate, and in the first and second stages, the cutoff frame is moved to a position different from the upper shaft. While holding in the engaged position, the third
a first locking member that releases the holding state of the cutoff frame in the step; and changing the driving speed of the drive means from high speed to low speed according to the position of the cutoff frame held by the first locking member. and a control means for stopping the driving of the driving means in the third stage;
and a second locking member that locks the cutoff frame together with the first locking member in the first and second stages; A drive stop device for a cycle sewing machine, comprising a holding member that engages with the second engaging member located at the second stage and maintains that position.