JPH06367U - Thread tension drive for sewing machine - Google Patents

Abstract

(57) [Abstract] [Objective] It is possible to reduce the load on the automatic presser foot lifting device 27, reduce the size of the device, and reduce power consumption without complicating the structure. [Structure] In synchronization with the vertical movement of the presser foot by the automatic presser lifting device 27, the presser foot side drive mechanisms 31, 3 of the thread tension adjuster 34.
2, 33, 36 and the thread cutting side drive mechanism 37 are driven,
The dish-shaped plate 34a of the thread tension device 34 is attached to the presser side driving mechanism 3
The control system is configured to be moved by both 1, 32, 33, 36 and the thread cutting side drive mechanism 37.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a thread tension meter for a sewing machine in which a thread tension device that applies a predetermined tension to a sewing thread supplied to a needle is automatically driven according to the situation to appropriately adjust the pinching force of the thread tension device. Device drive device.

[0002]

[Prior art]

 Generally, a sewing thread used in a sewing machine is guided to a sewing needle after a predetermined tension is applied through a thread tension device. The thread tension regulator has a pair of dish-shaped plates that sandwich the sewing thread, and one of the pair of dish-shaped plates is pressed to the other side by the biasing force from the coil spring to apply tension to the sewing thread. ing. By the way, in recent sewing machines, the dish-shaped plate of the thread tension device is drive-controlled in association with various mechanisms, and the tension of the sewing thread is automatically adjusted. Examples of various mechanisms with which the thread tension regulator is interlocked include an automatic presser foot lifting device that moves a cloth presser up and down, and an automatic thread trimming device that drives a thread cutting device for sewing thread.

The work clamp is vertically movable so as to hold down the material to be sewn near the needle drop point of the sewing needle, and is connected to the drive motor of the automatic presser lifting device via a predetermined link mechanism. Has been done. As shown in FIG. 4, the cloth presser drive signal S1 sent from the CPU (central processing unit) 1 constituting the control system through the driver circuit 2 is supplied to the drive motor 3 of the automatic presser lifting device. When applied, electric power is supplied from the power source VDD by the above-mentioned cloth presser drive signal S1 and the cloth clamp is moved up and down. At this time, the above-mentioned presser foot is connected to the dish-shaped plate of the thread tension regulator via the presser foot side drive mechanism including a predetermined cam mechanism and link mechanism, and the above-mentioned vertical movement of the presser foot is It is transmitted to the thread tension regulator via the drive mechanism, whereby the dish-shaped plate of the thread tension regulator is moved in synchronization with the vertical movement of the presser foot.

Further, the thread cutting means for cutting the sewing thread is operated by a thread cutting solenoid provided in the automatic thread cutting device, and as shown in FIG. 4, the CPU 1 sends the thread through the driver circuit 4. The thread cutting drive signal S2 is applied to the thread cutting solenoid 5 of the automatic thread cutting device. At this time, the thread cutting drive signal S2 is simultaneously applied to the plate floating solenoid 6 which constitutes the thread cutting side drive mechanism of the thread tension regulator, and is the same as the operation of the thread cutting means by the thread cutting solenoid described above. At this time, the dish floating solenoid 6 moves the dish-shaped plate of the thread tension regulator so that the tension of the sewing thread is automatically adjusted.

[0005]

[Problems to be solved by the device]

 However, as described above, in the conventional device, when the cloth presser is moved up and down, only the driving force of the drive motor 3 of the automatic presser lifting device causes the cloth presser to move up and down and the disc tension plate to move. Since both the movement and the movement are performed at the same time, the load on the drive motor 2 of the automatic lifting device is large. Therefore, in the past, there has been a problem that the automatic presser lifting device has become large in size and the power consumption of the automatic presser lifting device is large.

In view of the above, the present invention is capable of reducing the load on the automatic presser foot lifting device without complicating the structure, reducing the size of the device, and reducing power consumption. An object is to provide a drive device.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, a thread tension device control device of a sewing machine according to the present invention is an automatic presser foot lifter for holding a thread tension device that holds a sewing thread and applies a predetermined tension to the sewing thread. There are a mechanism for driving the thread retainer on the presser foot side, which is driven in tandem with the device, and a mechanism for driving the thread tensioner on the thread trimmer side, which drives the thread tensioner in conjunction with the drive device of the automatic thread trimming device for sewing threads. Each of them is drive-controlled based on the presser foot drive signal and the thread trimming drive signal, and both the presser foot side drive mechanism and the thread trimmer side drive mechanism of the thread tensioner are controlled based on the cloth presser drive signal. , It has a structure with a control system that drives simultaneously.

[0008]

[Action]

 In the thread tension regulator driving device of the sewing machine having such a configuration, in addition to the drive mechanism of the thread tension device on the pressure foot side being driven in synchronization with the vertical movement of the pressure foot by the automatic presser lifting device, The cutting side drive mechanism is simultaneously driven, and the dish-shaped plate of the thread tension regulator is moved by both the presser side drive mechanism and the thread cutting side drive mechanism. Therefore, the drive load of the automatic lifting device is reduced while maintaining the same structure as the conventional one.

[0009]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, as shown in FIG. 2, the presser bar 12 and a needle bar (not shown) are provided on the arm part 11a of the sewing machine 11 so as to project from the lower end of the arm part 11a so as to be vertically movable. Has been. The presser bar 12 and the needle bar are hung toward the sewing machine head 13 arranged in the lower part, and a sewing needle (not shown) is attached to the lower end part of the needle bar. A cloth presser 14 for pressing the material to be sewn near the needle drop point is attached to the lower end of the.

Further, as shown in FIG. 3, the presser bar dash 12 a provided at the upper end portion of the presser bar 12 is formed into a substantially L-shape via the knee raising bar 15. One end of the first knee lift link 16 is connected. The first knee lift link 16 is rotatably supported by a pin 17, and receives a downward biasing force from a coil spring 18 so as to press the knee lift bar 15 downward. . Further, the other end of the first knee raising link 16 is connected via a lateral raising rod 19 to one end of a second knee raising link 21 formed in a substantially L shape. The second knee-raising link 21 is rotatably supported by a pin 22, and the other end of the second knee-raising link 21 is formed in a substantially L-shape via a horizontal raising vertical bar 23. It is connected to one end of the third knee lift link 24. The third knee raising link 24 is rotatably supported by a pin 25, and the other end of the third knee raising link 24 is connected to a drive motor 27 via a worm gear 26. The presser bar 12 and the cloth presser 14 are moved up and down by the driving force from the drive motor 27 in the automatic presser lifting device having such a structure.

More specifically, as shown in FIG. 3, the presser bar tray 12a provided on the presser bar 12 is provided with a plate floating cam so as to constitute a cloth presser side drive mechanism of the thread tension regulator. 31 is fixed, and one end of the plate floating bar 32 is in contact with the inclined cam surface 31a of the plate floating cam 31. That is, when the presser bar 12 is moved up and down, the plate floating bar 32 is reciprocated substantially horizontally by the inclined cam surface 31a of the plate floating cam 31. The other end of the plate floating bar 32 is in contact with the middle portion of the thread loosening plate 33 from the left side in the drawing, and the plate floating bar 32 is reciprocally moved in a substantially horizontal direction as described above. Thus, the distance between the pair of dish-shaped plates 34a, 34a forming the thread tension regulator 34 is appropriately adjusted as described later.

The pair of dish-shaped plates 34 a, 34 a forming the thread tension device 34 sandwich the sewing thread 38 and apply a predetermined tension to the spindle 34 b fixed to the main body frame 35. Is inserted coaxially. A coil spring 34c mounted on the support shaft 34b is pressed against the outer plate-shaped plate 34a of the pair of plate-shaped plates 34a, 34a (on the right side in the drawing). The coil spring 34c is urged by the coil spring 34c. Thus, the dish-shaped plates 34a, 34a are arranged so as to be in a pressed state. Further, a dish floating pin 36 is slidably inserted from the inner side (left side in the figure) into the support shaft 34b, and a front end portion (right side end in the figure) of the dish floating pin 36 is connected to the outer side (right side in the figure). ) Is in contact with the plate-shaped plate 34a. The rear end portion (the left end portion in the drawing) of the plate floating pin 36 is in contact with the middle portion of the above-described yarn loosening plate 33 from the right side in the drawing.

The thread loosening plate 33 is composed of a flat plate-like member extending obliquely in the vertical direction, and the upper end portion of the thread loosening plate 33 is rotatably attached to the body frame 35 via a fulcrum pin 33a. In addition, the lower end portion is slidably attached to the output shaft of the disc floating solenoid 37 that constitutes the thread trimmer side driving mechanism of the thread tension regulator 34. As described above, the thread loosening plate 33 itself is rotatably mounted around the upper end portion, and the thread loosening plate 33 is attached to the thread loosening plate 33 from the plate floating pin 36 in the leftward direction in the drawing. That is, the urging force toward the plate floating bar 32 side is applied. The urging force presses the middle portion of the thread loosening plate 33 against the leading end of the dish floating bar 32, and the lower end of the thread loosening plate 33 causes the tip of the output shaft of the dish floating solenoid 37. It is pressed against the side of the stopper 37a provided on the. A large stopper 37b is provided in the middle of the output shaft of the plate floating solenoid 37. The yarn loosening plate 33 is rotated between these stoppers 37a, 37b. It is configured.

The dish floating solenoid 37 that constitutes the thread cutting side drive mechanism is operated in conjunction with an automatic thread trimming device (not shown), and outputs when the dish floating solenoid 37 is turned on. The axis is retracted. As a result, the thread loosening plate 33 is rotated toward the right side in the figure, and the space between the dish-shaped plates 34a, 34a of the thread tension regulator 34 is enlarged via the plate floating pin 36, as a result. The tension of the sewing thread 38 is designed to be weakened. On the other hand, when the dish floating solenoid 37 is turned off, the output shaft is pulled out as shown in FIG. 3, and the thread loosening plate 33 is rotated to the left side in the drawing. As a result, the distance between the dish-shaped plates 34a, 34a of the thread tension regulator 34 is reduced, and the tension of the sewing thread 38 is increased. In the normal sewing state, the dish floating solenoid 37 is maintained in the off state.

On the other hand, the automatic thread cutting device is provided with a thread cutting means (not shown) including a fixed knife and a moving knife, and a thread cutting solenoid for driving the thread cutting means. Drive control of the thread trimming solenoid of such an automatic thread trimming device, the plate floating solenoid 37 constituting the thread trimming side drive mechanism of the above-described thread tension device 34, and the drive motor 27 of the automatic presser lifting device The control system to be used will be described below.

As shown in FIG. 1, a CPU (central processing unit) 41 constituting a control system sends a cloth presser drive signal S 41 through driver circuits 42 and 45, and a driver circuit 44. , 45, the thread cutting drive signal S42 is sent out. The presser foot drive signal S41 sent through the driver circuit 42 is applied to the drive motor 27 of the above-described automatic presser foot lifting device. The cloth presser drive signal S41 supplies electric power from the power source VDD to move the cloth presser 14 up and down. Movement is taking place. At this time, as described above, the presser foot 14 is connected to the dish-shaped plate 34a of the thread tension regulator 34 via the presser foot side drive mechanisms 31, 32, 33, 36. Therefore, the above-described vertical movement of the cloth presser 14 is transmitted to the thread tension adjuster 34 via the above-mentioned cloth presser side drive mechanisms 31, 32, 33, 36, and the dish-shaped plate 34a of the thread tension adjuster 34 causes the cloth presser 14 to move. It is designed to be moved in synchronization with the vertical movement of the.

That is, when the presser foot 14 is lowered in the sewing state, the distance between the dish-shaped plates 34a, 34a of the thread tension regulator 34 is reduced, and the tension of the sewing thread 38 is reduced. Although it is strengthened, when the work clamp 14 is lifted after the sewing work is completed, the dish-shaped plates 34a, 34a of the thread tension regulator 34 are urged by the work clamp side drive mechanisms 31, 32, 33, 36 as described above. The space between them is increased and the tension 38 of the suture thread is reduced.

Further, the cloth presser drive signal S41 is applied to the drive motor 27 of the automatic presser lifting device, and at the same time, through the driver circuit 45, the dish floating solenoid which constitutes the thread cutting side drive mechanism of the thread tension regulator 34. It is also applied to the 37 side so that the dish floating solenoid 37 is turned on. Therefore, when the presser foot 14 is lifted after the sewing state is finished, as described above, the presser foot side drive mechanisms 31, 32, 33, 35 cause the tensioner 34 to move between the dish-shaped plates 34a, 34a. In addition to the increase in the distance, the disc floating solenoid 37, which constitutes the thread cutting side driving mechanism of the thread tension regulator 34, allows the spacing between the dish-shaped plates 34a, 34a of the thread tension regulator 34 to be increased. It is controlled to be enlarged.

On the other hand, the thread trimming drive signal S42 sent from the CPU 41 through the driver circuit 44 is applied to the thread trimming solenoid 43 of the automatic thread trimming device, and power is supplied from the power source VDD by this thread trimming drive signal S42. The thread trimmer (moving knife) of the automatic thread trimmer is configured to be activated.

As described above, at the same time as the thread cutting drive signal S 42 is applied to the thread cutting solenoid 43 of the automatic thread cutting device, the dish floating solenoid 37 which constitutes the thread cutting side driving mechanism of the thread tension controller 34 is connected to the disk floating solenoid 37. Again, the thread trimming drive signal S42 is applied through the driver circuit 45. As a result, the dish-shaped plate 34a of the thread adjuster 34 is moved in synchronization with the operation of the thread trimming means (moving knife) described above, and the tension of the sewing thread 38 is automatically adjusted. That is, when the sewing is finished and thread cutting is performed, the space between the dish-shaped plates 34a, 34a of the thread tension regulator 34 is enlarged by turning on the dish floating solenoid 37, and the tension of the sewing thread 38 is weakened. Is configured.

As described above, in this embodiment, the presser foot side drive mechanisms 31, 32, 33, 36 of the thread tension regulator 34 are operated in synchronization with the vertical movement of the presser foot 14 by the automatic presser lifting device. In addition to this, the dish floating solenoid 37 that constitutes the thread cutting side drive mechanism of the thread tension regulator 34 is turned on, and the dish-shaped plate 34a of the thread tension regulator 34 is moved to the presser foot side drive mechanisms 31, 32, 33, 36 and It is moved by both driving forces of the thread cutting side drive mechanism 37. Therefore, while maintaining the same hardware structure as the conventional one, the drive load of the automatic lifter is reduced.

[0022]

[Effect of device]

 As described above, the thread tension device drive device of the sewing machine according to the present invention drives the presser foot side drive mechanism and the thread trimmer side drive mechanism of the thread tensioner in synchronization with the vertical movement of the presser foot by the automatic presser lifting device. The control system is configured to move the dish-shaped plate of the thread tension regulator by both the presser foot side drive mechanism and the thread trimmer side drive mechanism.Therefore, the automatic presser foot without complicating the structure is used. The load on the lifting device can be reduced, the size of the device can be reduced and the power consumption can be reduced, and the reliability of the sewing machine can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control system of a sewing machine to which the present invention is applied.

FIG. 2 is a side view showing an outline of an automatic presser foot lifting device for a sewing machine.

FIG. 3 is a front explanatory view showing an outline of a cloth pressing side drive mechanism and a thread cutting side drive mechanism attached to a thread tension regulator of the sewing machine.

FIG. 4 is a block diagram showing a control system of a conventional sewing machine.

[Explanation of symbols]

 14 Cloth presser 31, 32, 33, 36 Cloth presser side drive mechanism 37 Disc floater solenoid (thread cutting side drive mechanism) 34 Thread tension device 34a Plate plate

Claims (1)

[Scope of utility model registration request] 1. A thread tension device comprising a pair of dish-shaped plates for sandwiching a sewing thread and applying a predetermined tension, an automatic presser lifting device for vertically moving a cloth presser that abuts on a material to be sewn, and the automatic presser lifting device. Drive mechanism of the thread retainer that adjusts the tension of the sewing thread by moving the dish-shaped plate of the thread tension regulator in conjunction with the drive of the thread tension regulator, and an automatic thread trimming device that activates the thread trimming means that cuts the sewing thread. And a thread trimmer side drive mechanism that adjusts the tension of the sewing thread by moving the dish-shaped plate of the thread tension device in conjunction with the drive device of this automatic thread trimming device, and when the fabric presser moves up and down. And, based on the presser foot drive signal and the thread trimming drive signal sent when the thread trimming means operates,
In a thread tensioner drive device of a sewing machine, which includes a control system for driving and controlling each of the presser foot side drive mechanism and the thread trimmer side drive mechanism of the thread tensioner, the control system sends out when the cloth presser moves up and down. The cloth presser drive signal is simultaneously applied to the thread trimmer side drive mechanism of the thread tension regulator, and the cloth presser side drive mechanism and the thread trimmer side drive mechanism are simultaneously driven and controlled based on the cloth presser drive signal. A thread tension device driving device for a sewing machine, which is configured as described above.