JPS5836998B2 - Sewing machine basting device - Google Patents

Description

[Detailed Description of the Invention] The present invention makes it extremely easy to perform tacking stitches, so-called lash stitches, in advance in the middle of the parts to be sewn as a preliminary preparation in order to prevent the fabrics from shifting when they are sewn together on top of each other in a sewing machine. The objective is to provide a new device that can

Conventional Shige-stitching involves overlapping the fabric to be sewn, ensuring that the fabric does not shift, determining the needle position for the fabric, stepping on the controller,
Lower the upper shaft of the sewing machine one rotation, and while stopping the needle above the throat plate, tie the fabric to the edge using both the upper and lower threads, release the controller, and then move the fabric by feeding the sewing machine to prevent it from shifting. Instead, a method is used in which the fabric is temporarily fastened by repeatedly overlapping operations such as manually feeding the fabric, positioning the needle on the fabric again, and stepping on the controller.

However, such a sewing example includes two states: sewing work and feeding the cloth by hand.

For this reason, when using conventional sewing machines to perform lash stitches, the thread tension is adjusted to an extremely low value so that it is easy to feed the fabric by hand, and the presser foot pressure is similarly set to an extremely low value. Then adjust the presser foot with a special presser foot called a lashing attachment (with a built-in spring so that pressure is generated when the presser foot moves downward). Alternatively, it was necessary to switch the l section of the motor control circuit so that when the controller is stepped on, the sewing machine rotates once and stops at a position above the needle.

In other words, in order to do shitsuge stitching, you need at least Doki 4.
The following steps are required as pre-operations (reverse operations are also required as post-operations).

The present invention does not require any pre-operation as described above, and is automatically ready by simply pressing the button provided on the surface of the sewing machine frame.After that, each time the controller is pressed, the sewing machine sews one needle in a good and reliable manner. It was designed so that the following was carried out.

Embodiments of the present invention will be described below with reference to the drawings.

First, as shown in FIGS. 4 and 6, the sewing machine according to the present invention stores sewing pattern signals in a semiconductor electronic storage device ROM and outputs the sewing pattern signals from a pulse generator attached to the upper shaft of the sewing machine. This is an electronic sewing machine with a built-in microcomputer in which the pattern memory is sequentially recalled and inputted to a pulse motor for generating width and feed by pulse signals generated in synchronization with shaft rotation.

As shown in FIGS. 1 to 4, the sewing machine of the present invention is equipped with an electric presser foot pressure adjusting device, an electric thread tensioner, an electric feed dog lowering device, and an upper shaft fixed position stopping device.

Briefly describing each device of the present invention below, the presser foot pressure adjusting device fixes a needle bar holder 3 to the middle part of a presser bar 2 having a presser foot 1 at its lower end, and connects the needle bar holder 3 and a spring presser piece above it. A presser foot pressure generating spring 15 is arranged between the spring presser piece 4 and the worm wheel 5, which has a lead cam portion b on its lower surface and a lead cam portion C facing the lead cam portion b. The upper limit is imposed by the metal 6 that is firmly attached to the sewing machine.

The worm wheel 5 is a reversible motor (servo motor)
It meshes with the worm 7 attached to the shaft of 8.

A potentiometer 11 is attached to the reversible motor 8 and is gear reduced.

Further, another potentiometer 13 that is moved by the presser foot pressure dial 12 is disposed on the sewing machine frame.

In addition, in FIG. 6, 60 is a pattern selection panel, which includes the potentiometer 13.

The presser foot pressure adjusting device having the above structure can be adjusted by setting the dial 12 exposed on the surface of the sewing machine frame as appropriate.
The signal read into the microcontroller through the D converter 61 is
/A converter 80K is output, resulting in potentiometer 13, reversible motor 8 and potentiometer 11 as shown in FIG.
The spring presser piece 4 is moved in the axial direction of the presser rod 2 by a servo system, and the pressure of the cloth presser is adjusted in accordance with the setting of the dial 12.

Next, to explain the thread tension device, there are two thread tension discs 20.
The plunger boss 22 that holds the plunger 21 is the plunger 2.
3, and the coil 2 in the solenoid machine frame 24
The supporting pressure between the two plates is changed depending on the magnitude of the current value.

When the thread tension dial 26, which is exposed on the sewing machine frame and has a potentiometer 27 included in the pattern selection panel 60 at the other end, is set appropriately, the potentiometer 27
The value is read into the microcomputer through the A/D converter 61, and a value corresponding to the value is outputted as a digital value to the thread tension device D/A converter 90.

The analog output that has passed through this D/A converter 90 is sent to an amplifier 9.
An example of an upper position stop device for a 6-order sewing machine in which current is passed through coil 25 through coil 25 and has a thread tension function is shown in Fig. 4. 30 is stopped at a fixed position by the engagement of the groove d of the disc 30 with the rotary member 32 by activation of an upper position stopping solenoid 31 provided on the sewing machine frame.

That is, in the process of rotating the sewing machine at low speed by operating the foot controller 70, the solenoid 31 is energized by the solenoid energization designation as a sewing machine stop designation signal, and the solenoid 31 is electrically operated to designate a stop, and the sewing machine is attached to the upper shaft of the sewing machine. The rotary member 32 engages with the cutout groove d of the disc 30, and the sewing machine is mechanically stopped at a fixed position.

Next, to explain the feed dog sinking device, the pulley/actuator 41 attached to the feed control pulse motor shaft 40K rotates the feed adjuster (not shown) to change the feed amount, and at the same time operates the solenoid 42. This makes it possible to engage with the L-shaped link 43 and give movement to the L-shaped link 43.

This movement of the L-shaped link 43 is magnified by the intermediate link 44 and gives movement to the lever 45 for sinking the L-shaped feed dog, and this movement causes the members 46, 4T to cancel the vertical component of the feed dog movement on the bottom surface of the sewing machine bed. give movement.

The pulse generator is composed of, for example, a set of LEDs 50 and transistors 51 and a shielding plate 52 (FIG. 6) attached to the upper shaft of the sewing machine, and generates pulses by shielding the upper shaft at a specific phase.

The present invention has the above-described configuration, and with reference to the control flowchart shown in FIG. 7 below, the program starts (S
TART), the initial routine etc. omitted with dashed lines are executed, and the key reading (Key Rea) for each switch operation including pattern selection etc. is executed.
d) is done.

When lash stitching is not specified, the presser foot pressure dial 12 and thread tension dial 26 are activated for normal sewing.

The routines for normal sewing when the release of basting is designated in the basting state are omitted and are shown by chain lines.

When the basting button 62 in the pattern panel 60 provided on the surface of the sewing machine frame is pressed, it is read that basting has been specified.

When it is determined that it is basting stitching, the feed dog sinking renoid 42 is first excited in process A according to the program (
Although the details are not described in the program, this excitation is executed only once for each new designation of the lash stitch.)
, the feed pulse motor 40 is rotated to lower the feed dog 48, and then in process B the sewing machine motor is set to low speed by the low/high speed switching circuit 110.

When the foot switch 71 in the controller 70, which specifies the operation and stop of the sewing machine motor, is OFF, the presser foot pressure and thread tension are released in process C. When the foot switch 71 is turned ON, that is, the controller is depressed, in process C', The presser foot pressure is automatically set to the appropriate value for binding as shown below, regardless of the value of L/12 (presser foot pressure diagram).

That is, the digital signal stored (or calculated) in the microcomputer as one corresponding to the appropriate value is output to the D/A converter 80, and becomes an input signal to the amplifier 810 as an analog quantity.

The amplifier 81 compares the input signal with a signal from a potentiometer 11 attached to the shaft of the reversible motor 8, and rotates the reversible motor 8 so that both values match. 5 to drive the spring presser piece 4 in the direction of the presser bar 2 to bring the presser pressure to the appropriate value.

Next, the thread tension device is also output from the microcomputer to the thread tension device D/A converter 90 so that it has an appropriate value regardless of the setting of the diamond/I/26, and the thread tension solenoid 25 is energized through the amplifier 91.

Subsequently, in process D, the sewing machine motor is started by applying an invalid signal to the motor stop circuit 110,
After waiting for the needle to move below the throat plate, when the needle reaches a predetermined lower phase, the pulse generators 50 and 51.52K output a pulse signal. ) The stop solenoid 31 is energized.

After the timer is activated in process F and a certain period of time limited by the timer operation (i.e., a time sufficient to always reach the stop phase even when the sewing machine rotates at a low speed) has elapsed, in process G the stop circuit 100 of the sewing machine motor is enabled. The sewing machine stops at the needle up position.

The upper stop solenoid 31 is turned off.

Subsequently, when the sewing machine is stopped, the 5VC presser foot pressure and thread tension regulator are released so that the cloth can be easily moved.

Thereafter, when the foot switch 71 is turned off, the program returns to IsTARTJ, and the sewing machine remains stopped with the presser foot pressure and thread tension released.

Furthermore, as can be seen from the flowchart in Fig. 7, unless the foot switch 71 is turned ON again after each one-stitch stitch, the handwheel can be turned by hand (the soil stop solenoid 31
is turned OFF), and the feed dog has sunk, and the presser foot pressure and thread tension device are not released, so it is advantageous to move the fabric by hand to determine the next needle position on the fabric.

As described above, in the basting sewing device of the present invention, since the sewing machine is in an appropriate sewing state when sewing the basting area, there are no sewing problems such as skipped stitches or thread breaks, and when the sewing machine is used to sew the basting area by hand, the sewing machine is in the proper sewing state. Regardless of whether the foot switch is in the ON or OFF state, the presser foot pressure and the thread tension device are released, so there are effects such as making it easier to feed the cloth by hand.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the vicinity of the presser foot of the sewing machine according to the present invention, Fig. 2 is a detailed view of a portion of Fig. 1, Fig. 3 is a detailed view of the thread tension regulator of Fig. 1, and Fig. 4 is a detailed view of the sewing machine. FIG. 5 is a perspective view of the width and feed generation mechanism of the sewing machine, FIG. 6 is a block diagram of the control circuit of the sewing machine, and FIG. 7 is a flowchart showing the binding stitch system. In the figure, reference numerals 8, 11, and 13 denote a reversible motor and a potentiometer, which are the main elements of the presser foot pressure adjustment device; 23, 25, a plunger and a coil, which are the main elements of the thread tension regulator; 30, 31, .
32 is a disc, solenoid and rotating member which are the main elements of the upper position stop device of the sewing machine; 41 to 44 are the pulley and operator, solenoid and link which are the main elements of the feed dog sinking device; 62 is a shishike button , 70 is a controller 7, 51 is a pulse generator, and in each process in FIG.
1 is a feed dog sinking control means, c and c' are presser foot pressure/thread tension control means, B and D are low speed rotation control means, E is an upper position stop control means, and F is a timer.

Claims (1)

[Scope of Claims] 1. In an electronic sewing machine that stores seam control signals in an electronic storage device to control seam coordinates, a binding stitch that is disposed in the sewing machine frame and that specifies a binding stitch by operation is provided. a button, an electric feed dog lowering device that lowers the feed dog to a state in which cloth feeding is disabled according to the basting designation, an electric presser foot pressure adjustment device that adjusts the presser foot pressure, and an upper thread tension adjustment device. An electrically operated thread tension controller for adjustment, a pulse generator that generates a pulse signal at a specific rotational phase of the upper shaft of the sewing machine, and a rotating machine that receives the sewing machine stop designation signal and operates electrically to designate a stop. an upper position stop device that forcibly stops the sewing machine at a predetermined needle top phase; a controller that controls the speed of the sewing machine including designation of operation and stop of the sewing machine motor; a feed dog sinking control means for controlling the sinking of the feed dog, and a feed dog sinking control means that releases the presser foot pressure of the presser foot pressure adjusting device and the thread tension of the thread tension device when the controller is designated to stop when lash stitching has been specified, and the operation is designated. a presser foot pressure/thread tension control means for electrically controlling the presser foot pressure and thread tension to a predetermined constant value when the sewing machine is in the sewing machine; a low-speed rotation control means for rotating the sewing machine at a constant low speed; and a low-speed rotation control means for causing the sewing machine to rotate at a constant low speed when receiving a designation for lash stitching; an upper position stop control means for performing the electric specified operation; and an upper position stop control means for controlling the sewing machine motor to operate in response to a pulse signal from the pulse generator when lash stitching is specified, and to stop the sewing machine motor after a predetermined time has elapsed; A basting device for a sewing machine, comprising a timer for designating electrical control of the presser foot pressure/thread tension control means and a timer for canceling and designating the electric specified operation of the upper position stop control means.