JPS6365891A - Method and apparatus for feeding cloth of sewing machine - Google Patents

Abstract

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

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention has a front feed table and a rear feed table that support the lower feed dog of a sewing machine and swing along a substantially elliptical trajectory, which are linked to the main shaft of the sewing machine. By supporting the lower feed dog with two fulcrums that move up and down, the effective feed amount in the horizontal direction of the lower feed dog is increased, preventing uneven fabric feed and unstable fabric feed, and ensuring uniform and good sewing. At the same time, the present invention provides a method and a device based on the phenomenon of the lower feed dog falling downward (which makes it possible to prevent poor digging into the fabric).

``Prior Art'' Conventionally, in this type of sewing machine, the rear part of the feed table is a fulcrum that is fixedly supported and cannot move up and down, and the feed table can only move up and down at the middle part of the feed table. Since it is supported, if one of the two fulcrums is fixed, the elliptical trajectory of the lower feed dog that moves accordingly has a small horizontal effective feed amount, If the fabric becomes uneven, the fabric progresses inconsistently, and it is difficult to sew evenly and well, or if the lower feed dog falls forward during sewing and the fabric does not dig into the fabric,
This has various drawbacks, such as the fact that adjustments cannot be made without stopping the operation of the sewing machine and removing the cover and related parts.

"Problems to be Solved by the Invention" When the lower feed dog moves along an elliptical locus of a sewing machine that feeds fabric using a seesaw, if the effective feed amount in the horizontal direction of the lower feed dog is small, the fabric will dig into the fabric. It is an object of the present invention to provide a method and a device that eliminates the disadvantages of conventional sewing machines such as poor fabric feeding, uneven fabric feeding, and unstable fabric advancement, and enables operation of the lower feed dog that can feed the fabric stably and uniformly. This is the purpose of

``Means for Solving the Problems'' In order to achieve the above object, the present invention provides a front feed table and a rear feed table which are linked to a feed shaft that performs a swinging motion in synchronization with the rotation of the sewing machine. The lower feed dog is supported at two fulcrums at the bottom, and both fulcrums move up and down, making it possible to increase the effective feed amount of the lower feed dog in the horizontal direction. It is possible to adjust the poor biting of the lower feed dog at any time and easily using the long leg adjustment pin provided.

"Example and operation" 1 is a feed shaft upper arm, and one end thereof is tightened to a feed shaft 23 which is connected to an eccentric shaft 25 linked to a known main shaft of the sewing machine by a connecting rod 26 so as to swing. are connected by screws 2, and are oscillated by the oscillating motion of the feed shaft 23.

Reference numeral 5 denotes a feed upper arm link, the lower end of which is pivotally attached to the tip of the upper arm 1 of the feed vertical shaft with a link pin 3.

The tip of the upper arm 6 of the upper and lower feed shaft is pivotally attached to the upper end of the upper upper arm link 5 with a link pin 3. 6 is a feed vertical shaft arm that transmits vertical movement to the rear corner piece 13 via the square piece shaft 12, and 8 is a feed guide push, which is fixed on the machine frame. 9 is a fixing screw for fixing the feed guide eccentric 10. 10 is a feed guide eccentric having an eccentric through hole 10a;
It is rotatably supported through the through hole 10b of the nif feed guide push. 12 is a square piece shaft, and the middle 12a is an eccentric through hole 10 of the feed guide eccentric 10.
a, the base end 12b is exposed outside the through hole 10a,
The upper arm 6 of the feed vertical shaft is fastened to the tip thereof with a screw 7 in a fixed manner. Reference numeral 11 denotes a long leg adjustment pin, which is screwed into the outer ring of the feed guide eccentric 10 so that the degree of eccentricity can be easily adjusted from the outside. 12G is the tip of the corner piece shaft 12, which is exposed at the end of the feed guide eccentric 10, is pivoted cautiously in the through hole 24 of the rear corner piece 13, and gives rise and fall movement of the rear corner piece 12 by axial movement. 17 is the advance table;
On the 1st, there is a gap 17a across the rear ends of both feed tables 1718, and the rear corner piece 13 is fitted into the gap 14. 14 is the square piece cover, and with the set screw 15, attach the rear corner piece 1.
3 to adjust the gap in the sliding direction of the rear corner piece 13. 18a is the lower gap, and the front feed table 1
7. Continuously installed on the intermediate lower surface across the rear feed table 18, and the front corner piece 1G
Insert. Reference numeral 28 denotes a through hole of the front corner piece 16, which passes through the eccentric shaft 25. The eccentric shaft is configured to be interlocked with the main shaft. 19 is the front feed dog, and the front feed table 17
It is connected to the tip of the screw 20 with a set screw 20, and 21 is a rear feed dog.
It is connected to the rear feed table 1 with a set screw 20a, and 22 is a small feed dog, which is connected to the rear feed dog 21 with a set screw 20b.

In addition, 26 is a known connecting rod connected to the main shaft,
This is a device for transmitting swing motion to the feed shaft 23.

The present invention has the above-described structure, and includes not only the front corner piece but also
The rear corner piece is also not fixed, but moves up and down, and while both the front and back corner pieces move up and down, they move along an elliptical trajectory in combination with the horizontal movement of the horizontal movement device. Since both fulcrums move horizontally while moving up and down, the front and rear feed tables, lower feed dog, etc. that are supported and interlocked increase the effective feed amount in the horizontal direction, and if the forward downward movement of the feed dog occurs. However, this phenomenon can be adjusted from outside the cover using the long leg adjustment pin.

``Effects of the Invention'' As described above, the present invention is supported by two front and rear supports that move up and down, and increases the horizontal feed amount of the lower feed dog through compound movement with the horizontal movement device, thereby reducing fabric feeding unevenness. This has the effect of preventing unstable fabric feeding and enabling uniform and good sewing, and the long leg adjustment pin allows you to adjust the knitting degree of the feed guide eccentric, and the lower feed dog can be adjusted at any time. Since the front drooping phenomenon is corrected and the material is made to bite into the fabric well, it is possible to achieve uniform and good sewing due to the even and good penetration of the fabric.

[Brief explanation of drawings]

The attached drawings show an example of the implementation of the present invention. Fig. 1 is a perspective view of the main part, Fig. 2 is an exploded perspective view of the main part, and Fig. 3 is the lower feed dog of the conventional machine and the lower feed of the present invention. FIG. 4, which is a comparison diagram of the movement locus with the teeth, is a schematic diagram of the movement of the feed table from the feed shaft. 1-Upper-feed axis upper arm, 2-Tighten with screw, 3-link pin, 4-set screw, 5-~feed upper arm link, 6
- Upper arm of feed vertical axis, 7-- Tighten with screw, 8-- Feeding guide push, 9-- Feeding guide eccentric fixing screw, 10-- Feeding guide eccentric, 1Qa- Eccentric through hole , I Ob--through hole, 11--long leg adjustment pin, 12--square piece axis, 12a--square piece axis intermediate, 1
2b -- Square piece shaft base end, 12 C- Square piece shaft tip, 13-
・-Rear corner piece, 14- Square piece cover, 15-- Set screw, 16-
Front corner piece, 17-front feed stand, 18-rear feed stand, 19-・front feed dog, 20.20a, 20b-・set screw, 21-
・-Rear feed dog, 22--Small feed dog, 23-Feed shaft, 2
4.--Through hole, 25-Eccentric shaft, 26.--Continuous rod, 2
7--horizontal movement device, 28-through hole. Applicant Yamato Sewing Machine Manufacturing Co., Ltd. (2 idiots) Figure 3 Figure 4

Claims (1)

[Claims] 1. A front feed table that supports the lower feed dog of the seesaw fabric feed sewing machine and swings along a substantially elliptical trajectory; and 2. A rear feed table that moves up and down in conjunction with the main shaft of the sewing machine. A seesaw material feeding method for a sewing machine characterized by supporting the material using individual fulcrums. 2. Insert a rear corner piece into the rear of the front feed table and rear feed table, which support the lower feed dog of the seesaw fabric feed sewing machine and swing it along an approximately oval trajectory, and flatten the rear corner piece. The eccentric shaft is fixed to the tip of the mandrel, and the eccentric shaft is fixed to a feed guide eccentric having an eccentric through hole in such a manner that the eccentricity can be adjusted, and the feed guide eccentric is fixed to a stationary feed guide eccentric. A feed vertical shaft upper arm is rotatably inserted into the push shaft and is connected to the base of the eccentric shaft to transmit the swinging motion of the feed shaft via a link device, and the feed shaft is connected to the main shaft. A front corner piece is fixed to the main shaft in an eccentric manner, and the front corner piece is inserted into the intermediate portion of the front feed table and the rear feed table, and The feed table is supported by two supporting points on the rear corner piece and the front corner piece, which move up and down as the sewing machine operates, and the lower feed dog moves along a nearly elliptical trajectory until the lower feed dog reaches the highest position. A seesaw fabric feeding device for a sewing machine, characterized in that the effective feed amount in the horizontal direction is increased. 3. Insert a rear corner piece into the rear part of the front feed table and rear feed table, which support the lower feed dog of the seesaw fabric feed sewing machine and swing it along an approximately oval trajectory, and flatten the rear corner piece. It is fixed to the tip of the center shaft, and the eccentric shaft is passed through a feed guide eccentric having an eccentric through hole through which the eccentricity can be arbitrarily adjusted and fixed with a long leg adjustment pin. A guide eccentric is rotatably inserted through a stationary feed guide push, and a feed vertical shaft upper arm is connected to the base of the eccentric shaft via a link device so as to transmit the swinging motion of the feed shaft. , the feed shaft is connected to a main shaft for synchronized rocking movement, a front corner piece is fixed to the main shaft in an eccentric manner, and the front corner piece is fitted into an intermediate portion of the front feed table and the rear feed table. The lower feed dog is moved along a substantially elliptical trajectory while the rear feed table and the front feed table are supported by two supporting points of a rear corner piece and a front corner piece, which respectively move up and down as the sewing machine is operated;
A seesaw fabric feeding device for a sewing machine characterized by increasing the effective feed amount in the horizontal direction until the lower feed dog reaches the highest position.