JPS6068892A - Drive apparatus of automatic sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides an automatic sewing machine that moves a presser foot that holds a workpiece in a fixed shape using a memory element such as a FROM, and obtains seams of a fixed shape. Regarding the drive device.

In particular, the present invention relates to a drive device for an automatic sewing machine that can suppress vibrations of a presser foot device in an automatic cloth feeding sewing machine.

[Prior art]

An example of a drive device of a conventional automatic sewing machine is shown in FIG. 1 and will be explained. In the figure, 1 is the head of the sewing machine that forms the stitches, 2 rotates together with the upper shaft of the head 1 of this sewing machine,
A detector that generates a specific number of pulses and needle up and needle down position signals. 3 is a sewing machine motor that rotates the sewing machine; 4 is a sewing machine driver that drives this sewing machine motor 3; these constitute a driving device that drives the sewing machine.

5.6 is a pulse motor that drives a presser device (not shown) that clamps the workpiece in each of the orthogonal x and y directions;
These constitute the XY drive mechanism section 1. 8.9 is a pulse motor driver that drives the pulse motors 5 and 6, respectively; 10 is a sending pulse train generation circuit that supplies pulses corresponding to the pulse motors 5 and 6; these constitute a positioning drive device together with the pulse smoke 5 and 6. .

11 is a sewing machine start switch (sewing machine switch), 1
2 is a switch that moves the presser foot up and down, and 13 is a central processing unit (hereinafter referred to as CP) that controls each part.

), 14.15 is the data input/output capo), 1
6i1 system control memory, 17 data temporary memory, 1B pattern data memory, 19 data bus, 2 (H-t address bus, 21 inputs the output of the pulse train generation circuit 10 and the output of the input/output board 15)
, 21a, and is an AND gate that performs the logical product of these two forces and passes the pulse train.

The sewing machine 1 that forms the stitches, the drive device that drives the sewing machine 1, the positioning device that positions the presser foot device that clamps the workpiece based on pre-programmed data, and the control that controls each of these devices. Device (CPU)
The presser foot device is configured to intermittently drive the presser foot through the data in synchronization with the rotation of the sewing machine 1.

The operation of the drive device of the automatic sewing machine configured as described above will be explained.

First, when the presser foot switch 12 is stepped on, the presser foot lowers, and the workpiece to be sewn is clamped by the presser foot. And the sewing machine switch (sewing machine start switch)
11, the sewing machine driver 4 is driven through the input/output boat 14, whereby the sewing machine motor 3 starts rotating and the sewing machine 1 starts rotating. At the same time,
The CPU 13 reads fabric feed data for one stitch in synchronization with the needle down position signal of the sewing machine from the pattern data memory 18 into which the sewing pattern data is input, and sends the data to the feed pulse generation circuit 10 through the input/output boat 14. Output.

Next, from this feed pulse train generation circuit 10, pulses corresponding to the amount of cloth feed synchronized with the rotation of the sewing machine are sent to the AND gate 2.
Output to 10 input 21b. At this time, input/output boat 1
5 outputs the input 21aK' high level of the AND gate 21, and outputs the pulse train from the above-mentioned pulse train generation circuit 10 to the pulse motor driver 8.9, which drives the pulse motors 5, 6 of each of the X and Y axes. are respectively driven to move the distribution presser by a predetermined feed amount.

The above operation will be explained with reference to FIG. 2, which is a time chart showing the operation timing of each part. In Fig. 2, (a) shows the needle bar motion of the Ifi sewing machine, (b) shows the needle down position signal obtained by the detector 2, and (C) and (d) show the needle bar motion of the Ifi sewing machine. input 21
a and input 21b% (e) indicate the vibration of the presser foot device. In (,), (a) indicates the needle bar of the sewing machine, (b) indicates the throat plate surface, (c) in (d) indicates the cloth feeding period, and (b) indicates the cloth feeding stop period.

The needle down position signal shown in FIG. 2(b) for the needle bar motion of the sewing machine shown in FIG. 2(-) and the input 21b of the AND gate 21 shown in FIG. Input 21 from input/output boat 15 to AND gate 21. The relationship (see FIG. 2(c)) is shown in FIG. 2 as described above. Part 1. The feed pulse train from the pulse train generation circuit 10 is transmitted to the pulse motor driver 8.9.
When input to
) to move (see (c)). When the feed pulse train input is completed, the presser foot repeats undershoot and overshoot as shown in Fig. 2(e).
Attenuates and converges to a predetermined position.

However, in the drive device of such an automatic sewing machine, the presser foot and the workpiece are still vibrating even when the feed pulse train is completed and the sewing machine needle enters the workpiece (workpiece). There were disadvantages in that the stitch length became unstable, the stitching quality deteriorated, and the quality of the workpiece to be sewn was significantly degraded.

[Summary of the invention]

In view of the above points, the present invention has been made in order to solve such problems and eliminate such drawbacks, and its purpose is to provide a presser foot and a workpiece, which is a sewn product, held by the presser foot with a simple structure. To provide a drive device for an automatic sewing machine capable of eliminating instability of stitch length and deterioration of sewing condition caused by vibrations and preventing deterioration in quality of a workpiece caused by vibrations of a presser foot.

In order to achieve such an object, the present invention includes a means for suppressing damped vibrations that is activated when the positioning drive of the presser foot device is stopped, and suppresses damped vibrations that occur when the positioning drive of the presser foot device is stopped due to intermittent driving. It was designed to suppress it.

[Embodiments of the invention]

FIG. 3 is a block diagram showing an embodiment of a drive device for an automatic sewing machine according to the present invention, and only the parts necessary for explanation are shown.

In FIG. 3, the same symbols as in FIG. 1 indicate corresponding parts, 22 is an inverter that inverts the polarity of the output of the input/output port 15, and 23 is an electromagnetic brake driver that receives the inverted output of this inverter 22. , 24 are electromagnetic brakes driven by the output of this driver 23.

The electromagnetic brake 24 is attached to the shaft of a pulse motor that drives the presser foot, and is actuated when the positioning drive of the presser foot is stopped to suppress and control damped vibrations.

Next, the operation of the embodiment shown in FIG. 3 will be explained with reference to FIGS. 4 and 5.

FIG. 4 shows a time chart for explaining the operation of FIG. 3, and FIG. 5 shows a final diagram of an embodiment showing the relationship between the pulse motor and the electromagnetic brake. - And in FIG. 4, (a) is the needle bar motion of the sewing machine, (b) is the needle down position signal obtained by the detector 2, (c) is the input 21a of the AND gate 21, (d)
is the output 22. of the inverter 22. , (e) shows the input 2tb of the AND gate 21, (r) shows the vibration of the presser foot, (,
), (a) is the needle bar of the sewing machine, (b) is the throat plate surface, (
In d), (c) is the on period of the electromagnetic brake 240, in) is the off period of the electromagnetic brake 24, and (e) in (e) is the cloth feeding period.

(f) indicates the cloth feeding stop period. In Figure 5, 5a
is the shaft of the pulse motor 5, 25 is a sleeve fixed to this shaft 5a, 26 is a leaf spring fixed to this sleeve 25, 27 is an armature fixed to this leaf spring 26, 2
8 is a magnet, 29 is a magnet coil, 38 is a brake shoe, 311d pulse motor 5 and magnet 2B
This bracket 31 is attached to the xygeffi structure T (see FIG. 3) of the main body of the F5F3 sewing machine.

First, since the functions of each of the 09 components of the sewing machine 1 to the AND gate 21 are the same as those of the device shown in FIG. 1 described above, the explanation thereof will be omitted here. When the feed pulse train corresponding to the stitch pitch is input to the pulse motor drivers 8 and 9 through the AND gate 21, the AND gate 2
The input 21g of the AND gate 21 becomes a high level, and when the supply of the transmission pulse train is completed, the input 21aF of the AND gate 21 becomes the high level.
In the current state, pulses to the pulse motor driver 8.9 are no longer supplied.

At this time, the input 2111 of the AND gate 21 is input to the inverter 22, its inverted level is output from the output terminal, and this output is input to the driver 23 of the electromagnetic brake 24. This driver 23 operates the electromagnetic brake 24 when a high level is input, and deactivates the electromagnetic brake 24 when a low level is input.

Next, as mentioned above, FIG. 5 shows the relationship between the pulse motor 5 and the electromagnetic brake 24. When a high level is input to the driver 23 of the electromagnetic brake 24 shown in FIG. Excited, armature 2T
is attracted to the coil side through the bending of the leaf spring 2G, comes into contact with the brake shoe 30, and causes an action that prevents the rotation of the pulse motor 5.

This operation will be explained with reference to FIG. Here, this fourth
Sewing machine needle bar motion shown in (,) in the figure.

The needle down position signal shown in (b), the input 21a of the AND gate 21 shown in (C), and the AND gate 21 shown in (e)
The relationship of the input 21b is similar to that of the device shown in FIG.
(See Figure 2).

Since the input 21a of the AND gate 21 passes through the inverter 22 and the inverted level of the input 21a is input to the electromagnetic brake driver 23, the electromagnetic If the brake 24 does not operate (see (c) in FIG. 4(d)),
In order to suppress the vibration of the pulse motor 5, the vibration of the presser foot, which is mechanically connected to the pulse motor shaft 5a shown in FIG. 5, is also suppressed from undershoot and overshoot, as shown in FIG. 4(f)K. That will happen.

In this way, by activating the electromagnetic brake 24 attached to the movable part of the positioning drive device that drives the presser foot device when the drive of the presser foot device is stopped, the positioning drive of the presser foot device that occurs due to intermittent operation can be stopped. It is possible to suppress the damped vibration at the time.

In addition, in the above embodiment, the case where an electromagnetic brake is used as a vibration suppressing means is explained as an example, but the present invention is not limited to this, and other brakes such as a band brake, an axial pressure brake, a block brake, etc. A stopping device for a brake device or a shock absorbing device such as a damper can be used in the same way, and damped vibrations when the positioning drive of the cloth presser device is stopped can be suppressed.

〔Effect of the invention〕

As described above, according to the present invention, the vibration of the sewing product caused by the intermittent drive of the presser foot during sewing is suppressed by the means for suppressing damped vibration, which is activated when the positioning drive of the presser foot device is stopped. This solves the problem of unstable stitch length and deterioration of stitching tension caused by vibrations of the presser foot and the sewing material held by it, and prevents deterioration in the quality of the material being sewn. The practical effect is extremely good as a beautiful and high quality sewn product can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a drive device for a conventional automatic stitching machine, FIG. 2 is a time chart for explaining the operation of FIG. 1, and FIG. 3 is an embodiment of a drive device for an automatic stitching machine according to the present invention. FIG. 4 is a block diagram showing an example. FIG. 4 is a time chart for explaining the operation of FIG. 3. FIG. 5 is a block diagram of the embodiment showing extracted parts related to the pulse motor, lightning, and magnetic brake. 1. Fist sewing machine, 2. Yu/m heavy equipment, 3-... Sewing machine motor, 4... Sewing machine driver, 5.6...
・Pulse motor, 8, 9...Pulse motor driver, 10''...Transmission pulse train generation circuit, 11...
Sewing machine switch, 12φ... Fabric presser switch, 13.
...CPU (control device), 23...electromagnetic brake driver, 24@-...electromagnetic brake. Agent Masuo Oiwa

Claims (1)

[Claims] α) A sewing machine that forms stitches, a drive device that drives this sewing machine, a positioning drive device that positions a presser foot device that clamps a workpiece according to preprogrammed data, and each of these devices. A control device that controls the device, and an automatic sewing machine that drives the presser foot device intermittently to communicate the data in synchronization with the rotation of the sewing machine, operates when the positioning drive of the presser foot device is stopped to control damped vibration. A drive device for an automatic sewing machine, characterized in that it is equipped with a means for (2) The drive device for an automatic sewing machine as set forth in claim 1, wherein the means for suppressing damped vibration, which is activated when the positioning drive of the presser foot device is stopped, is attached to a movable part of the positioning drive device.