JPH03186290A - Sewing device for forming stitch onto cantilever supported work - Google Patents

Abstract

PURPOSE:To obtain a sewing device not to generate sewing deviation even onto a cantilever supported work by changing the feeding amount of a needle feeding mechanism provided in a sewing machine corresponding to the moving velocity of the sewing machine or the work and the sewing velocity of the sewing machine. CONSTITUTION:A microcomputer for sewing machine control controls the rotation of a main shaft rotation motor and a needle feeding amount control motor, calculates the optimum needle feeding amount and outputs the calculated amount to the sewing machine. The command of sewing, the moving velocity data of the sewing machine and sewing velocity data are outputted from an articulated robot controller to the microcomputer for sewing machine control. By integrating these data, the microcomputer for sewing machine control calculates needle feeding amount data based on the moving velocity data of the sewing machine and the sewing velocity data to be sent from the articulated robot controller and controls the needle feeding amount control motor. Then, sewing is executed with the optimum needle feeding amount at all times and the sewing deviation can be prevented.

Description

[Detailed Description of the Invention] A1 Objective of the Invention [Field of Industrial Application] This invention provides a sewing machine that does not have an internal cloth feeding mechanism and a work piece that moves continuously relative to each other at a constant speed. The present invention relates to a sewing device such as a three-dimensional sewing device that forms seams on a workpiece that is held and supported.

[Conventional technology]

2. Description of the Related Art Hitherto, as a sewing method using a three-dimensional sewing device, there are two known methods: a method in which a workpiece is fixed and sewing is performed by moving a sewing machine, and a method in which a sewing machine is fixed and sewing is performed by moving a workpiece. Although there is a difference in whether the sewing machine or the workpiece is moved, both methods have in common that the seams are formed by relative movement between the sewing machine and the workpiece.

With such sewing devices, it is difficult to control the fabric intermittently using the internal feed dog, which is done in existing sewing machines, due to machine control considerations such as moment of inertia and vibration. This is not adopted, and instead a method is adopted in which either the sewing machine or the workpiece is moved continuously at a constant speed to sew.

[Problem to be solved by the invention]

In a conventional three-dimensional sewing device, the seam allowance of the armhole of the workpiece protrudes from the supporting portion of the workpiece and is supported on a cantilever. Therefore, during sewing, the gap between the presser foot and the throat plate is set to be slightly larger than the thickness of the fabric, and the workpiece is sewn floating between the presser foot and the throat plate, so the upper thread is tightened by tension. is pulled in the same direction as the feeding direction,
There is a problem that sewing errors occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sewing device that does not cause any seams even when the sewing device forms seams on a cantilevered workpiece.

1. Structure of the Invention [Means for Solving the Problem] In order to achieve the above object, the sewing device of the present invention for forming a seam on a cantilever-supported workpiece is a sewing machine that does not have an internal cloth feeding mechanism. A device that moves one of the workpieces relative to another continuously at a constant speed, and the sewing machine is equipped with a needle feed mechanism so that the amount of feed can be changed according to the movement speed of the sewing machine or workpiece and the sewing speed of the sewing machine. It is something.

[For production]

A sewing device that forms a seam on a cantilever-supported workpiece configured as described above calculates needle feed amount data based on movement speed data and sewing speed data of the sewing machine or workpiece, and adjusts the needle feed amount accordingly. Quantity is controlled.

〔Example〕

This will be explained with reference to the figures.

With reference to FIG. 1, the three-dimensional automatic sleeve attaching system will be explained as an example in which the workpiece side is fixed and the sewing machine side is moved.

A body 3 and sleeves 4 are three-dimensionally supported on the support body 1 while being turned inside out. A compact sewing machine 6 is installed at the tip of the articulated robot 5, and the sewing machine 6 goes around the armhole to attach sleeves. When the sewing of one arm is completed, the table 2 rotates to attach the other sleeve.

The three-dimensional automatic armhole attaching system is characterized in that the part of the armhole to be sewn protrudes from the support 1 and is supported in a cantilevered manner, which is different from workpiece support in normal sewing. In addition, shirring is sometimes performed near the shoulder of the oil-side armhole, which tends to cause misalignment when sewing this area.

Here, as a means to prevent such misalignment,
Employs needle feed.

The needle feed mechanism is shown in FIGS. 2-4. In connection with this, the drive path from the upper shaft to the needle swing section will be explained.

An eccentric cam 8 is fixed to the upper shaft 7, and the prongs of the trifurcated arm 9 engage with the eccentric cam 8. One end of the trifurcated arm 9 is then attached to the square piece 10 of the needle oscillation adjuster 11 for sliding guidance. The base end of the trifurcated arm 9 is connected to the swinging arm 15 . The swinging arm 15 is fixed to a swinging shaft 16, and another swinging arm 17 is fixed to the swinging shaft 16. Swinging arm 17
is connected via a connecting link 18 to a needle bar stand 19 to which a needle bar 20 is fixed.

When the upper shaft 7 is driven and the eccentric cam 8 rotates, the forked arm 9
swings, and the movement is transmitted to the swinging arm 15. As a result, the swing arm 17 also swings via the swing shaft 16, and the swing is transmitted from the connection link 18 to the needle bar stand 19.

The needle bar stand 19, that is, the needle bar 20 is connected to the upper shaft 2I.
It swings back and forth in the sewing direction indicated by the arrow in FIG.

This swing amount, that is, the needle feed amount can be adjusted by changing the inclination angle of the needle swing adjuster ll. The angle of inclination of the needle swing adjuster 11 is changed by rotating the needle feed amount control motor 13 via a gear.

An origin detection plate 12 is fixed to the shaft of the needle feed amount control motor I3, and the needle feed control origin switch 14 cooperates with this to detect the needle feed control origin, that is, the position of the needle bar 20 in the sewing direction. The point where the amount of oscillation becomes zero is detected.

This will be further explained with reference to the control block diagram in FIG.

The sewing machine control microcomputer controls the rotation of the main shaft rotation motor and the needle feed amount control motor 13, calculates the optimum needle feed amount, and outputs it to the sewing machine.

The articulated robot controller outputs sewing commands, movement speed data of the sewing machine 6, and sewing speed data to the sewing machine control microcomputer.

Putting these together, the sewing machine control microcomputer calculates needle feed amount data based on the sewing machine movement speed data and sewing speed data sent from the articulated robot controller, controls the needle feed amount control motor, The sewing machine always sews at the optimum needle feed rate to prevent sewing errors.

That is, the faster the moving speed is relative to the sewing speed of the sewing machine 6, the thicker the needle feed amount, in other words, the amount of swing of the needle bar 20 in the sewing direction. This is because the longer the needle thread is, the greater the amount of tension caused by tightening the upper thread in the sewing direction, so the needle feed amount must be increased to counteract this.

Further, when sewing is completed and the needle feed control origin signal is sent to the needle feed control motor controller, the needle feed control motor rotates to detect the origin and the needle feed amount becomes zero. Since thread trimming is performed in this state, the reliability of thread trimming is not reduced.

Although the above embodiment describes a three-dimensional sewing device, the field of application of the present invention is not limited to this. It is configured like this, so
This produces the effects described below.

In other words, it is possible to sew a cantilever-supported work piece such as a three-dimensional sewing machine in good condition without causing any seam deviations, just like normal sewing in which the work piece is supported on a table. can. Therefore, the quality of sewn products is improved.

[Brief explanation of drawings]

Figure 1 is a front view of the three-dimensional automatic sleeve attaching system as an example of fixing the workpiece and moving the sewing machine, Figure 2 is a front sectional view of the needle feed mechanism, and Figure 3 is the same as Figure 2. A ZZ sectional view, FIG. 4 is a diagram of a needle feed adjuster in the needle feed mechanism, and FIG. 5 is a control block diagram. l - Support body, 6 - Sewing machine, 7 - Upper shaft, 8 Eccentric cam, 9 - Forked arm, 11 - Needle feed adjuster, I2 Detection plate, I3 - Needle feed amount control motor, 14 Needle feed control Origin switch, 15. 17-- = swinging arm, 16 swinging axis, 19 - needle bar stand, 20- Needle Bar Industrial Technology Agency Director Ken Sugiyu

Claims (1)

[Claims] 1. A sewing machine that does not have an internal cloth feeding mechanism and a workpiece are moved continuously relative to each other at a constant speed. A sewing device that forms seams on a cantilever-supported workpiece that can be changed according to the sewing speed of the sewing machine.