JPH078654A - Cloth feeder for sewing machine - Google Patents

Abstract

PURPOSE:To provide a cloth feeder for a sewing machine which can feed accurately even the cloth having stages. CONSTITUTION:A cloth feeding roller 10 provided behind a pressure metal is divided into a first roller 10a and second roller 10b. The roller shafts 12a, 12b of the respective rollers 10a, 10b are supported by a pair or roller arms 6a, 6b supported swingingly and pressed downward by a spring. One roller shaft 12a is rotated by a predetermined angle in one direction by the upper shaft of a sewing machine as a drive shaft to rotate the first roller 12a and the rotation of the first roller 10a is transmitted through a slide type universal joint 30 to the second roller 10b. When the cloth has stages, one of the first and second rollers 10a, 10b is shifted upward to the other and the relative shift of both roller 10a, 10b is absorbed by the universal joint 30 so that the first and second rollers 10a, 10b make contact respectively with the cloth.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cloth feeding device for a sewing machine.

[0002]

2. Description of the Related Art A cloth feeding device in which a cloth feeding roller is provided on the back of a presser foot in a sewing machine and the cloth feeding roller is intermittently rotated in one direction to feed the cloth is disclosed in Japanese Patent Publication No. 1-295.
No. 94 publication.

[0003]

By the way, in the conventionally known cloth feeding device, since the cloth for sewing is fed by contact with a single cloth feeding roller, the cloth is fed to the sewing position of the cloth. When there is a step, the cloth feed roller comes into contact with only the upper part of the cloth to feed the cloth. Therefore, there is a problem that the contact between the roller and the cloth is small and the cloth cannot be fed with high accuracy.

An object of the present invention is to provide a cloth feeding device which can feed cloth with a step difference with extremely high accuracy.

[0005]

In order to solve the above-mentioned problems, according to the present invention, a cloth feed roller provided at the back of a presser foot is intermittently rotated by a predetermined angle in one direction with the upper shaft of a sewing machine as a drive shaft. In the cloth feeding device of the sewing machine, the cloth feeding roller is divided into a first roller and a second roller,
A roller shaft that supports each roller is supported by a roller arm that is swingably supported, and each roller arm is pressed downward by a spring, and the first roller and the second roller are connected by a slide-type universal joint. The adopted configuration was adopted.

Here, as the slide type universal joint, a pair of cylinders mounted in the shaft insertion holes of the first roller and the second roller, a pair of pieces slidably assembled in the respective cylinders, and a pair thereof. And a pair of pieces having the same shape as the inner surface of the cylindrical body, and each of the outer peripheral surfaces of the piece having an arc surface centered on the central axis of the piece. It is possible to adopt the above-mentioned configuration.

[0007]

With the above structure, the rotation of one of the first roller and the second roller can be transmitted to the other roller via the universal joint.
The cloth can be fed by the contact between the roller and the second roller. If there is a step in the sewn part of the cloth, the first roller and the second roller
The roller moves up and down relatively by an amount corresponding to the step of the sewn portion. At this time, the transmission shaft of the universal joint is tilted to absorb the relative movement of the first roller and the second roller, and each roller is held in line contact with the cloth. Can be sent.

[0008]

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

As shown in FIGS. 1 to 3, a pair of bearings 3, 3 provided on an upper portion of a bracket 2 is attached to a support shaft 1 attached to a sewing machine arm. Bracket 2
Has a bearing block 4 at the bottom, and the bearing block 4
An arm support shaft 5 parallel to the support shaft 1 is supported on the.

The arm support shaft 5 penetrates through the bearing block 4, and one end of each of the pair of roller arms 6a and 6b is rotatably supported by both ends of the bearing block 4 located outward from both side surfaces of the bearing block 4. There is.

A spring bearing 7 is attached to the upper surfaces of the roller arms 6a and 6b, and the roller arms 6a and 6b are provided between the spring bearing 7 and the adjusting screw cylinder 8 screwed into the bearing portion 3 of the bracket 2. A spring 9 for pressing downward is incorporated.

A cloth feed roller 10 is incorporated between the other ends of the roller arms 6a and 6b. This cloth feed roller 1
0 is arranged on the back of the presser foot A as shown in FIG.

As shown in FIGS. 3 and 4, the cloth feed roller 10 is divided into a first roller 10a and a second roller 10b. Each roller 10a, 10b has a shaft insertion hole 1
1, the first roller shaft 12a and the second roller shaft 12b have one ends inserted into the shaft insertion holes 11 and are fixed by tightening the screws 13.

A sleeve 1 is provided outside the first roller shaft 12a.
4 is attached, and its sleeve 14 is inserted through an insertion hole 15 formed at the other end of one roller arm 6a.

On the other hand, the second roller shaft 12b is inserted into an insertion hole 16 formed at the other end of the other roller arm 6b.

A drive cylinder 17 is provided at the end of the sleeve 14, and a rod 19 is connected to a connecting piece 18 provided on the drive cylinder 17.

Although not shown in the drawing, the rod 19 is driven by transmitting the rotation of the upper shaft of the sewing machine to the drive cylinder 17 like the cloth feeding device for the sewing machine described in Japanese Patent Publication No. 29594/1989. The cylinder 17 is rotated in the forward and reverse directions by a predetermined angle.

A one-way clutch 20 is incorporated between the drive cylinder 17 and the sleeve 14. One-way clutch 2
6, a plurality of cam surfaces 22 forming a wedge-shaped space with the outer circumference of the sleeve 14 are formed on the inner circumference of the outer ring 21 fixed to the drive cylinder 17 at equal intervals in the circumferential direction, as shown in FIG. Then
A roller 23 is provided between each cam surface 22 and the outer peripheral surface of the sleeve 14.
And an elastic member 24 that presses the roller 23 toward a narrow portion of the wedge-shaped space. The one-way clutch 20 is a drive cylinder 17 shown in FIG.
Only the rotation in the direction indicated by the arrow is transmitted to the first roller shaft 12a via the sleeve 14.

As shown in FIG. 4, a slide type universal joint 30 for transmitting the rotation of the first roller 10a to the second roller 10b is provided between the first roller 10a and the second roller 10b. .

The universal joint 30 has shaft insertion holes 11, 11 for the first roller 10a and the second roller 10b.
A pair of cylindrical bodies 31, 31 inserted into the
It is composed of a pair of pieces 32, 32 slidably assembled inside each tubular body 31, and a transmission shaft 33 connecting the pair of pieces 32, 32.

The inner surfaces of the cylindrical members 31, 31 are shown in FIGS.
On the other hand, the piece 32 has the same shape as the inner surface shape of the tubular body 31, and each outer peripheral surface of the piece 32 is an arc surface 34 having its center on the central axis of the piece 32. ing.

As shown in FIG. 4, between the sleeve 14 and the roller arm 6a and between the second roller shaft 12b and the roller arm 6b, the first roller shaft 12a rotates in the direction of the arrow shown in FIG. And a detent mechanism 40 that prevents the rotation in the opposite direction.

Here, the sleeve 14 and the roller arm 6a
The rotation preventing mechanism 40 and the second roller shaft 1 incorporated between
Since the detent mechanism 40 incorporated between the roller arm 2b and the roller arm 6b has the same structure, one detent mechanism 4
Only 0 will be described below, and description of the other detent mechanism 40 will be omitted.

The rotation stopping mechanism 40, as shown in FIG.
A plurality of cam surfaces 42 forming a wedge-shaped space with the outer circumference of the sleeve 14 are formed at equal intervals in the circumferential direction on the inner circumference of the outer ring 41 inserted into the insertion hole 15 of the roller arm 6a and prevented from rotating. The roller 4 is attached to the cam surface 42 and the outer peripheral surface of the sleeve 14.
3 and the elastic member 44 that presses the roller 43 toward the narrow portion of the wedge-shaped space, the roller 43 is provided with the cam surface 4
2 and the outer peripheral surface of the sleeve 14 prevent the first roller shaft 12a from rotating in the direction of the arrow in FIG.

Now, when the drive cylinder 17 rotates in the forward and reverse directions by a predetermined angle, the rotation of the drive cylinder 17 in the direction shown by the arrow in FIG. 6 is transmitted to the sleeve 14 and the first roller shaft 12a via the one-way clutch 20. Then, the first roller 10a rotates.

The rotation of the first roller 10a is transmitted to the second roller 10b via the universal joint 30.

Therefore, the first roller 10a and the second roller 10b rotate in the direction of the arrow in FIG. 5, and the cloth is sent toward the rear of the presser foot A by the contact with the first roller 10a and the second roller 10b. be able to.

First roller 10a and second roller 10b
When the cloth B sent by the contact with is folded back and has a step as shown in FIG. 9 and the high step faces the first roller 10a, the first roller 10a moves by an amount corresponding to the step of the cloth B. The two rollers 10b move upward.

At this time, the transmission shaft 33 of the universal joint 30 is inclined, and the piece 32 slides along the inner surface of the cylindrical body 31 to move the first roller 10a and the second roller 1a.
Absorb relative movement with 0b. Therefore, the first roller 10a and the second roller 10b are held in linear contact with the cloth B, and the cloth B is fed in one direction by the rotation of the rollers 10a and 10b.

[0030]

As described above, in the cloth feed device for the sewing machine according to the present invention, the cloth feed roller is divided into the first roller and the second roller, and the first roller and the second roller are slidable. Because it was connected with the universal joint of
Each of the first roller and the second roller can be surely brought into contact with the stepped cloth, and the cloth can be fed with extremely high accuracy.

Further, since the first roller and the second roller are connected by the universal joint, the rotation of one roller can be transmitted to the other roller, and each roller is independently driven. The roller driving mechanism can be simplified as compared with the case of performing it.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a cloth feeding device for a sewing machine according to the present invention.

FIG. 2 is a partially cutaway side view of the above.

FIG. 3 is a partially cutaway plan view of the above.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

5 is a sectional view taken along line VV of FIG.

6 is a sectional view taken along line VI-VI in FIG.

FIG. 7 is a sectional view taken along line VII-VII of FIG.

FIG. 8 is an exploded perspective view showing a cylinder and a piece of the universal joint of the same.

FIG. 9 is a cross-sectional view showing a feeding state of cloth.

[Explanation of symbols]

 A Foot 6a, 6b Roller arm 9 Spring 10 Cloth feed roller 10a 1st roller 10b 2nd roller 12a 1st roller shaft 12b 2nd roller shaft 30 Universal joint 31 Cylindrical body 32 Piece 33 Transmission shaft 34 Arc surface

Claims (2)

[Claims] 1. A cloth feeding device of a sewing machine, wherein a cloth feeding roller provided on a back portion of a presser foot is intermittently rotated by a predetermined angle in one direction with an upper shaft of a sewing machine as a drive shaft. It is divided into two rollers, and a roller shaft for supporting each roller is supported by a roller arm that is swingably supported, and each roller arm is pressed downward by a spring so that the first roller and the second roller A cloth feed device for sewing machines, characterized in that they are connected by a slide type universal joint. 2. The cloth feed device for a sewing machine according to claim 1, wherein the universal joint is slidable in each of the pair of cylinders attached to the shaft insertion holes of the first roller and the second roller. It consists of a pair of built-in pieces and a transmission shaft connecting the pair of pieces, and the inner surface of the cylindrical body is rectangular, the pair of pieces has the same shape as the inner surface shape of the cylindrical body, and each outer peripheral surface of the piece is A cloth feed device for a sewing machine, which has an arcuate surface having a center on the center axis of the piece.