JP2006051169A - Material displacement preventive feeder for flat stitch sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material displacement preventive feeder for a flat stitch sewing machine suitably used for sewing material using a composite material such as a thin stretch material in particular by ensuring material feed in front and in the rear of a stitch forming position. <P>SOLUTION: A flat stitch sewing machine having a throat plate 1 and a material presser foot 2 arranged to face in a vertical direction across the front and rear of the stitch forming position A, is provided with front upper and lower feed dogs 3, 4 arranged to face in the front upper and lower sides of the stitch forming position A, and a rear lower feed dog 5 arranged at the rear lower part of the stitch forming position A so as to face the front material presser foot 2. The rear upper part of the stitch forming position A is provided with rear upper feed dog 6 facing the rear lower feed dog 5, and the material B immediately after stitched is held and carried backward from the stitch forming position A by the rear upper feed dog 6 and the rear lower feed teeth 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is configured by using two or more threads of a needle thread that penetrates the fabric and a thread that forms a loop or a decoration on the upper and lower surfaces of the fabric. The present invention relates to a fabric misalignment prevention feed device for a flat stitch sewing machine capable of simultaneously performing the above.

This type of flat stitch sewing machine is widely used for sewing or edge stitching of knitted fabrics and knitted fabrics because it can produce reliable seams with excellent elasticity and excellent strength.
As a cloth feed device in this flat stitch sewing machine, a feed dog is arranged on the lower side before and after the needle drop position (seam configuration position) of the sewing needle, a cloth presser is arranged on the upper side, and a feed dog on the lower side. Is moved forward by the feed mechanism in the cylinder bed, moved backward while being lowered at the forward end, moved forward again while being lifted at the backward end, and thereafter driven to repeat this substantially rectangular motion. The upper and lower fabric pressers can be reciprocated in the front-rear direction by the vertical movement of the presser bar on the sewing machine arm and the operating mechanism at the lower end of the presser bar. The fabric before and after the needle drop position is clamped from the top and bottom, fed forward, released and returned backwards in conjunction with the up and down motion of the sewing needle (stitch configuration motion) and the fabric intermittently forward What It is known that as issued Ri (see Patent Document 1).

Further, conventionally, a feeding device in which a cloth presser and an upper feed dog (provided on the front side of the needle drop position) on the upper side is also known (see Patent Document 2).
JP-A-10-305183 JP-A-10-156077

  However, in the conventional feeders of Patent Documents 1 and 2, when used for sewing a fabric made of a composite material such as a thin stretch material, before and after the stitch configuration position, in particular, the fabric on the rear side of the stitch configuration position. The feed is likely to be uncertain. For this reason, for example, since it is difficult for the cloth to come out from the state where the cloth is placed on the throat plate nail, there is a problem that troubles such as sewing spots, clogging, and cloth displacement occur. In particular, recently, due to the upsurge and diversification of fashion, there is a tendency for products with specifications using composite materials such as thin stretch materials to increase, and the above problem has become prominent.

  The present invention provides a fabric feed prevention device for a flat stitch sewing machine that is suitable for sewing a fabric using a composite material such as a thin stretch material, which ensures fabric feed before and after the stitch configuration position. It is an object.

In order to achieve the above object, the present invention has a needle plate and a fabric presser arranged vertically opposite to each other across the front and back of the stitch configuration position, and the front upper and lower sides arranged opposite to the front and top of the stitch configuration position. In a flat stitch sewing machine provided with a rear lower feed dog disposed opposite to the cloth presser at the lower rear portion of the feed dog and the stitch configuration position,
A rear upper feed dog that opposes the rear lower feed dog is provided at the rear upper portion of the stitch configuration position, and the fabric immediately after the stitch configuration is formed by the rear upper feed dog and the rear lower feed dog is the stitch configuration position. It is characterized in that it is configured to be nipped and conveyed backward.

According to the above configuration, it is possible to ensure the feeding of the fabric before and after the stitch configuration position. In particular, if the thin stretch fabric is sandwiched between the upper and lower feed dogs before the stitch and is scraped, Since the material fabric is not easily pulled out from the state, the material fabric is squeezed with the feed teeth on the back and up after the stitches are formed, and the material fabric is intruded. Sewing without spots can be performed.
The rear upper feed dog is attached to an upper feed rod to which the front upper feed dog is attached.

According to the above configuration, there is no need to newly provide an upper feed mechanism for the rear upper feed dog, and the configuration can be simplified and can be easily implemented.
Further, the cloth presser is provided with a slit or a hollow portion in which the rear upper feed dog protrudes and protrudes toward the needle plate side.
According to the above configuration, the rear upper feed dog can be installed at an appropriate position in the upper rear portion of the stitch configuration position without changing the length and width of the fabric presser, and the fabric just after the stitch configuration is sewn. It can be securely held and conveyed to the rear of the eye configuration position.

  According to the present invention, a fabric feed prevention device for a flat stitch sewing machine that is suitable for sewing fabrics that use a composite material such as a thin stretch material is ensured to ensure fabric feed before and after the stitch configuration position. can do.

Hereinafter, embodiments of the apparatus of the present invention will be described based on the drawings.
FIG. 1 is a schematic side view of an essential part of the device of the present invention. In FIG. 1, a needle plate 1 and a fabric presser 2 which are vertically opposed to each other across the stitch configuration position A are shown. Front feed upper and lower feed dogs 3 and 4 disposed opposite to the front and upper sides of the configuration position A, and a rear lower feed dog 5 disposed to face the cloth presser 2 at the lower rear of the stitch configuration position A, and A rear upper feed dog 6 facing the rear lower feed dog 5 is provided at the rear upper part of the stitch configuration position A, and a seam is formed immediately after the rear upper feed dog 6 and the rear lower feed dog 5 are stitched. The fabric B is configured to be nipped and conveyed to the rear of the stitch configuration position A.

  As shown in FIG. 2, the stitch construction position A is a position where the sewing needle 7 moves up and down and cooperates with a looper (not shown) or the like installed in the lower portion of the needle plate 1 to constitute a stitch. It becomes. The needle plate 1 is installed on the upper surface of a sewing machine bed (not shown), and has a needle drop hole 8 of the sewing needle 7 and a slit 9 in which the front and rear lower feed dogs 4 and 5 appear and disappear. The sewing needle 7 is installed at the lower end of a needle bar (not shown), and this needle bar is arranged in the tip of a sewing machine arm (not shown). The sewing machine arm is cantilevered substantially horizontally on the sewing machine bed by a column portion at the base end.

The dough presser 2 is attached to the lower end of a presser bar 10 (see FIG. 2) that can be moved up and down within the tip of the sewing machine arm via a mounting arm 11. A slit 13 in which the upper feed dogs 3 and 6 appear and disappear is formed.
The front upper and lower feed dogs 3 and 4 are arranged to oppose the upper and lower sides of the stitch configuration position A, and sandwich and convey the fabric B on the needle plate 1 toward the stitch configuration position A. For this purpose, the front upper feed dog 3 is attached to the lower end of an upper feed bar 14 (see FIG. 2) which is disposed in a front and rear front and rear direction in a substantially rectangular motion via a top feed mechanism (not shown) in the tip of the sewing machine arm. It is attached via the arm 15. Further, the front lower feed dog 4 is disposed in the sewing machine bed below the needle plate 1 through a lower feed mechanism (not shown) so as to move in a substantially rectangular manner up and down. These feed mechanisms of the upper and lower feed dogs 3 and 4 are configured to synchronize with each other, and these motions are configured to synchronize with a drive mechanism (not shown) of the sewing needle 7. The amount of movement in the front-rear direction by the feed mechanism of these front and lower feed dogs 3 and 4 can be changed and adjusted within a predetermined range.

The rear lower feed dog 5 is arranged in the sewing machine bed below the needle plate 1 on the rear side of the stitch configuration position A so as to be able to move in a substantially rectangular manner up and down and front and rear via a lower feed mechanism (not shown). This lower lower feed dog 5 lower feed mechanism is configured to feed the fabric B to the rear side of the stitch configuration position A by an amount corresponding to the stitch pitch (adjustable setting). 3 and 4 and the drive mechanism of the sewing needle 7 are configured to be synchronized with each other.
The rear upper feed dog 6 is opposed to the rear lower feed dog 5 and is arranged on the upper rear side of the stitch configuration position A so as to be able to move in a substantially rectangular manner in the vertical direction and in synchronization with the front upper feed dog 3. is there. Although the feed mechanism of the rear upper feed dog 6 can be provided separately in the sewing machine arm, in this embodiment, the upper feed bar 14 is used in order to use the same feed mechanism as the front upper feed dog 3. It is made to attach to the lower end of (refer FIG. 2) via the attachment arm 16. FIG.

The embodiment of the apparatus of the present invention has the above configuration, and the operation will be described next.
When the fabric B is set and sewing is started, the sewing needle 7 moves up and down, and in conjunction with this, the upper and lower feed dogs 3 and 4 on the front side (left side in FIG. 1) of the seam configuration position A are approximately. A rectangular motion is performed, and the fabric B is nipped and conveyed toward the stitch configuration position A. The looper at the lower part of the needle plate 1 receives the thread that the sewing needle 7 has passed through the fabric B and constitutes a stitch, and while the sewing needle 7 returns, the front, rear, upper and lower feed dogs 3, 4, and 5, 6 However, the fabric B is clamped before and after the stitch construction position A, and is normally fed to the right side of FIG. 1 by the stitch pitch. Thereafter, this operation is repeated to perform flat stitching. In particular, in the device according to the present invention, the fabric B before the stitch configuration in front of the stitch configuration position A (left side in FIG. 1) is nipped and conveyed by the upper and lower feed dogs 3 and 4, and the stitch configuration position A The fabric B immediately after the seam configuration at the rear (right side in FIG. 1) is also conveyed by being sandwiched by the upper and lower feed dogs 5 and 6, so that the fabric B can be fed out before and after the seam configuration position A. Become. Now, for example, if the feeding of the fabric B behind the stitch configuration position A (the right side in FIG. 1) is uncertain, the fabric B stays irregularly at the stitch configuration position A and “intrusion” In this state, if the stitches are formed by the sewing needle 7 and the looper, the stitch pitch is disturbed, stitch spots are formed, and the fabric B is displaced. This tendency is particularly noticeable in thin knit fabrics and stretch fabrics. However, in the device according to the present invention, the fabric B is held at the stitch configuration position A even after the stitch configuration position A by sandwiching the fabric B with the upper and lower feed dogs 5 and 6 and reliably transporting it. No irregular stagnation occurs, and sewing can be performed with no disturbance in the stitch pitch, no stitching spots, and no fabric shift.

  The configuration and operation of the embodiment of the apparatus of the present invention are as described above. However, the present invention is not limited to this embodiment, and is appropriately modified within the meaning and scope described in the claims. May be. Further, although only one sewing needle 7 is illustrated, flat sewing can be performed by using two or more sewing needles.

It is a side view which shows the principal part outline of this invention apparatus. It is a disassembled perspective view which shows the principal part outline of this invention apparatus.

Explanation of symbols

A stitch configuration position B fabric 1 throat plate 2 fabric retainer 3 front upper feed dog 4 front lower feed dog 5 rear lower feed dog 6 rear upper feed dog 7 sewing needle 8 needle drop hole 9 slit 10 presser bar 11 attachment arm 12 sewing machine Needle passage hole 13 Slit 14 Upper feed bar 15 Mounting arm 16 Mounting arm

Claims (3)

It has a throat plate and a fabric presser that are opposed to each other in the vertical direction across the stitch configuration position, and the front and upper feed dogs that are arranged to be opposed to the front and top of the stitch configuration position and the rear of the stitch configuration position. In a flat stitch sewing machine having a rear lower feed dog arranged at the lower part facing the fabric presser,
A rear upper feed dog that opposes the rear lower feed dog is provided at the rear upper portion of the stitch configuration position, and the fabric immediately after the stitch configuration is formed by the rear upper feed dog and the rear lower feed dog is the stitch configuration position. A fabric misalignment prevention feed device for a flat stitch sewing machine, characterized in that it is nipped and conveyed to the rear of the machine.   2. The apparatus for preventing cloth slippage of a flat stitch sewing machine according to claim 1, wherein the rear upper feed dog is attached to an upper feed bar to which the front upper feed dog is attached. 3. The cloth slip prevention feed device for a flat stitch sewing machine according to claim 1, wherein the cloth presser is provided with a slit or a hollow part in which the rear upper feed dog protrudes and protrudes toward the needle plate side. 4. .

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