JPH0214765Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a means for preventing workpiece cloth from shifting in a cloth holding device in a button sewing machine.

[Prior Art] FIG. 4 shows a side view of a main part of an example of a cloth holding device in a conventional neck wrapping button sewing machine of this type.

As is well known, this type of sewing machine is configured to sew buttons onto a workpiece cloth by transferring needles between two upper and lower needle bars.
The work cloth is held by the illustrated work cloth holding mechanism 40, and is moved to a button holding mechanism (not shown) while being moved in a predetermined manner by an X-Y direction drive device (only the X direction moving table 37 is shown). Sew the attached button.

Since the conventional example 40 shown in FIG. 4 is well known, only the outline of the configuration will be described. 41 is the X direction moving table 37
A base 42 fixed on the top is a first moving body that can be moved on the base 41 by each roller 43, and a cloth holding plate 45 having a U-shaped notch 44 at the tip is provided on the top. Fixed. The first moving body 42 is biased to the right in the figure by a compression coil spring 46.

Further, 47 is a second moving body disposed on the upper surface of the base 41 in front of the first moving body 42, and each roller 4
8, the fabric clamping plate 50 is movable on the base 41, and has a cloth clamping plate 50 fixed at its tip, which has a notch 49 that corresponds to the notch 44 at the tip of the cloth holding plate 45. The movement range of the second movable body 47 is restricted by a lower notch 51 and a stopper 52, and is biased away from a chuck mechanism (not shown) by a compression coil spring 54. In addition, in the figure, 55 is a locking arm, and 57 is an operating arm.

The work cloth to be buttoned is held between the tip notch 44 of the cloth holding plate 45 and the notch 49 of the cloth pincer plate 50, and the button sewing part is projected/exposed to the upper right of the holding part. In this state, the cloth holding plate 45 was folded back to the left side in the figure so as to be held between the upper and lower sides.

[Problems to be solved by the invention] However, in the conventional work cloth holding device as described above, a predetermined gap is set between the tip of the cloth holding plate 45 and the cloth sandwiching plate 50. , and the abutting parts between the two are relatively smooth, so no positive holding force can be obtained.
If only the pressing force of the spring 46 or the like is used, there is a possibility that the work cloth will be displaced due to movement and feeding in the X-Y direction during the button attaching process. When sewing decorative button parts, etc., the folding position from the clamping part is quite far away, so the body fabric cannot be sufficiently clamped.
The lining fabric and the outer fabric may overlap, causing problems in stitching around the neck of buttons, stitching with a stay stitch, etc., and potentially impairing the quality of the sewing product.

This invention was devised in view of the problems of the prior art as described above, and aims to provide a cloth holding device of this type that forcibly holds a workpiece cloth to prevent the cloth from shifting.

[Means for Solving the Problems] Therefore, in this invention, the cloth holding member of the work cloth holding device has a protrusion protruding from the tip cloth holding portion at least during button sewing work to hold the work cloth. The above objective is achieved by configuring the device to be forcibly restrained.

[Function] With the above configuration, it is possible to prevent the front/lining of the work cloth from shifting when attaching buttons, and to ensure the quality of the sewing product.

[Example] This invention will be explained below based on an example.

FIGS. 1a and 1b are a side view and a top view of a main part of an embodiment of a cloth holding member of a cloth holding device according to this invention.

(Structure) The cloth holding member of this embodiment is composed of two pieces of tongues F1 and F2 at the tip and the base.
1 is designed to be able to rotate approximately 90 degrees with respect to the tongue R2 around the pin 3 between the workpiece cloth holding state and the workpiece removal state position (shown by the solid line in Figure A). A bifurcated bracket 2a is fixed to the top of the tongue R2 on the base side, and the tongue F on the tip side
The pin joint portions 1 are assembled so as to be sandwiched between the forked portions 2a, and are mutually pivotally supported by pins 3.

On the other hand, two stepped holes 1a are bored in the main body of the tongue F1 in the longitudinal direction, and each rod 5 is disposed inside each hole so as to be slidable in the axial direction. The tip of the rod 5 forms a protrusion 5a, and a cylindrical block 5b is fixed to the base, and a bracket of the tongue R2 is inserted into the large diameter part of the stepped hole via a compression coil spring 6. It is elastically brought into contact with the surface of the bifurcated portion of 2a.

The block abutting surface of the bracket 2a is approximately
They intersect at an angle of 90 degrees, and the intersection angle part is formed into a smooth continuous curve 2b, and the distance (radius) of each contact surface from the center of pin R
are set as f and r, respectively, and f>r.

(Operation) As is obvious in Figure 1 a and b, the tongue F
1 is holding the work cloth at its tip, each rod 5 is pushed up as the block 5b comes into contact with the bifurcated abutment surface having a radius f, and the tip protrusion 5a of the rod 5 The dimensions are selected so that it protrudes by approximately (fr).

When setting the work cloth prior to the button attaching process and when removing the work cloth from the holding device after the button attaching process, the tongue F1 is manually set in the first position.
When rotated to the almost right angle position shown by the dotted line in figure a,
The block 5b of each rod 5 slides on the bifurcated contact surface, and the tip protrusion 5a of the rod 5 is (fr)
Tongue F so that it will not get in the way.
It automatically immerses from the tip of 1.

Since the block contact surfaces at each of the above two positions are planar, at both fixed positions,
The posture is stabilized by the detent action of the spring 4, and when rotating, the curved portion 2b allows smooth and easy operation.

As a result of the above, when attaching buttons, the tongue F
The protrusion 5a of No. 1 is attached to a cloth clip plate (not shown in Fig. 4).
0), the outer material and the lining will not be misaligned due to movement in the X-Y direction, even in relatively thick body materials such as formal wear. It does not impair the operation of attaching and detaching the cloth.

(Other Examples) Note that the protrusion 5 of the rod 5 in the tongue F1
In the above embodiment, the tongue R2
The radius difference (f
-r), but this retracting means is not limited to this, for example, as shown in FIGS. 2 and 3, side views of the main parts during sewing work and during removal, respectively. , eccentric pin E, and other means may also be used. 2 and 3 only explain the principle of the eccentric pin E, and the details are omitted. In the diagram,
The same (equivalent) components as in FIG. 1 are represented by the same symbols. Also, W is work cloth, B is button, N
indicates a needle, T indicates a thread, 20 indicates a neck wrapping portion, and 21 indicates a fabric presser.

Moreover, in this invention, it is of course possible to achieve the original purpose without employing a bending mechanism.

[Effects of the invention] As explained above, according to this invention, at least during button sewing work, since the protrusion is configured to protrude from the tip of the cloth holding member, there is no possibility of cloth shifting during the workpiece work. It is now possible to prevent this and ensure the quality of sewing products.

[Brief explanation of the drawing]

FIGS. 1a and 1b are a side view and a top view of essential parts of one embodiment of the cloth holding member according to this invention, respectively, and FIGS. 2 and 3 show the working state and workpiece removal state of another embodiment. FIG. 4 is a side view of the main parts of an example of a conventional cloth holding device. 1/2...Tang F/R, 3...Pin, 5...
Rod, 5a... protrusion.

Claims (1)

[Scope of utility model registration request] In a button sewing machine, needles are transferred between two needle bars that move up and down close to and apart from each other, and a button is sewn onto a workpiece fabric held by a workpiece fabric holding device placed between the needle bars. A cloth holding device for a button sewing machine, characterized in that a protrusion is made to protrude from the tip of a cloth holding member of the cloth holding device at least during button sewing work.