JPS6244954B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a differential feed mechanism for a sewing machine, and more particularly to a differential feed mechanism for a sewing machine in which the height of one feed dog can be changed relative to the height of the other feed dog. It is.

In a differential feed mechanism in which a pair of feed tables each having a feed dog mounted on the front end are arranged side by side so as to be relatively displaceable in the front-back direction, the height of one feed dog cannot be changed relative to that of the other. requested. In order to meet such demands, conventionally, one feed dog and
Although a spacer was interposed between the feed dog and the front end of the feed base on which the feed dog was mounted, the spacer had to be replaced every time the height was changed, which was unbearable. Further, the height and change could only be changed in stages.

An object of the present invention is to provide a differential feed mechanism that eliminates such problems, and its main purpose is to slidably fit a shaft into an elongated hole formed in one feed base, and A differential feed mechanism of the sewing machine is constructed by connecting an eccentric bush rotatably fitted into a hole formed in a feed table and rotatably connected to the shaft.

Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. 1 to 6, a differential feed mechanism 10 of a sewing machine includes a pair of feed tables 1 arranged in parallel.
1 and 12. A feed dog 14 is fixed to the front end 11a of the feed base 11 by a screw 13, and a screw 1 is fixed to the front end 12a of the feed base 12.
5, the feed dog 16 is fixed. A slot 17 that opens downward is formed in the rear end 11b of the feed base 11, and a hole 1 is formed in the slot 17.
A cam ring member 19 having a cam ring 8 is fitted therein. A first eccentric cam 20 is rotatably fitted into the hole 18, and when the first eccentric cam 20 rotates, the cam ring member 19 reciprocates back and forth while sliding up and down within the slot 17. It is becoming more and more common. In this way, the feed base 11 is reciprocated in the front and rear direction by the rotation of the first eccentric cam 20.

The rear end portion of the feed table 12 has a first part 12b and a second part 1.
2c, and both are fixed with screws 21. A slot 22 that opens rearward is formed in the first part 12b.
A cam ring member 24 having a hole 23 is fitted into the hole 2 . A second eccentric cam 25 is rotatably fitted into the hole 23, and when the second eccentric cam 25 rotates, the cam ring member 24 slides back and forth within the slot 22 and reciprocates up and down. It is becoming more and more like this. Further, a slot 26 opening downward is formed in the second portion 12c, and a cam ring member 28 with a hole 27 is formed in the slot 26.
are fitted. Therefore, a third eccentric cam 29 is rotatably fitted into the hole 27, and the rotation of the third eccentric cam 29 causes the cam ring member 28 to reciprocate in the longitudinal direction while reciprocatingly sliding in the vertical direction within the slot 26. It is becoming more and more common. In this way, the feed base 12 is simultaneously reciprocated in the front-rear direction and the up-down direction, making an elliptical motion as a whole.

Elongated holes 30 and 31 corresponding to each other are formed in the feed tables 11 and 12, respectively.
Square pieces 32 and 33 are fitted into and 31, respectively. Holes 34 and 35 are formed in the square pieces 32 and 33, respectively, and the square pieces 32 and 33 are fitted into the elongated holes 30 and 31, respectively. Thus, holes 34 and 35 are formed in the square pieces 32 and 33, respectively, and a shaft portion 38b of an eccentric pin 38 rotatably supported by the wall portion 37 of the bed 36 is rotatably inserted into the holes 34 and 35. It is fitted. The shaft portion 38b of the eccentric pin 38 is eccentric from the head 38a, and the distance between the feed dogs 14 and 16 and the throat plate 39 is adjusted by rotating the head 38a. Also, feed stand 1
When 1 reciprocates in the front-rear direction, its elongated hole 30 is guided by a square piece 32, and when the feed base 12 also reciprocates in the front-rear direction, its elongated hole 31 is guided by a square piece 33. You are becoming guided. Therefore, the first eccentric cam 20 and the third eccentric cam 2
By varying the amount of eccentricity of the feeders 9, the stroke of the feeder 11 in the longitudinal direction relative to the feeder 12 can be changed. That is, the feed tables 11 and 12 can be relatively displaced in the front-back direction. Furthermore, when the feed table 12 is reciprocated in the vertical direction by the second eccentric cam 25, the feed table 11 is also reciprocated in the vertical direction via the eccentric pin 39 and the square piece 32, and this vertical direction The reciprocating motion of the feed table 11 is combined with the reciprocating motion of the
The whole body also moves in an elliptical motion.

In addition to the elongated hole 30, another elongated hole 40 is formed on the front end side of the feed base 11, and a shaft member 41 is fitted into the elongated hole 40 so as to be slidable in the front-rear direction. That is, the shaft member 41 consists of a head 41a, a corner 41b, a shaft 41c, and a threaded portion 41d, and the corner 41b is slidably engaged with the elongated hole 40. A hole 42 corresponding to the elongated hole 40 is formed in the feed base 12, and an eccentric bush 43 is rotatably fitted into this hole 42. The shaft body 41c and threaded portion 41d of the shaft member 41 are inserted into the hole 44 of the eccentric bush 43, and the threaded portion 41d is screwed into the nut 45. In this way, the eccentric bushing 43 and the shaft member 41 are connected, but when the nut 45 is loosened and the eccentric bushing 43 is rotated with respect to the shaft body 41c, the feed base 12 is rotated about the eccentric pin 39, so that the feed The height of the tooth 16 can be changed relative to that of the feed dog 14.

The first eccentric cam 20, the second eccentric cam 25, and the third eccentric cam 29 are fixed to the lower shaft 50, and the first eccentric cam 20 and the second eccentric cam 25 are connected. That is, a square bridge flange 51 is formed at the right end of the first eccentric cam 20, and a hole 52 that is eccentric to the first eccentric cam 20 is provided through the first eccentric cam 20 and the square flange 51. . A flange 53 is formed at the left end of the second eccentric cam 25, and the second eccentric cam 25 and the flange 53 are provided with a flange 53 so as to be concentric with the hole 52.
A hole 54 is provided through the hole 54 so as to be eccentric to the hole 5 . A groove 55 is formed in the flange 53.
A square flange 51 is fitted into the square flange 51 . A screw 57 is screwed into a screw hole 56 formed in the flange 53, and the collar 5
7a engages with a notch 51a of the square flange 51. The first eccentric cam 20 has a screw hole 38, the second eccentric cam 25 has a screw hole 58, and the flange 53
Screw holes 60 are respectively provided in the radial direction, and screws 61, 62 and 63 are screwed therein.
is fixed to a lower shaft 50 passing through holes 52 and 53. The third eccentric cam 29 is also fixed to the lower shaft 50 with a screw (not shown).

To describe the operation in the above configuration, the lower shaft 50
When rotates, the first eccentric cam 20, the second eccentric cam 25, and the third eccentric cam 29 rotate, and the cam ring members 19, 24, and 28 slide back and forth in the vertical direction within the slot 17, respectively. , while reciprocatingly sliding in the slot 22 in the front-rear direction, and reciprocating in the front-rear direction while sliding reciprocatingly in the slot 26 in the up-and-down direction. Then, the feed table 12 is simultaneously driven in the vertical direction and the front-back direction, and the feed table 11 is driven in the front-back direction, and the reciprocating motion of the feed table 11 in the vertical direction is transmitted via the eccentric pin 38, and the feed table 11 and 12 makes an elliptical motion as a whole. Therefore, the feed dogs 14 and 16 mounted on the front ends 11a and 12a of the feed tables 11 and 12, respectively, move in an elliptical manner and move in and out of the throat plate 39. If a difference is provided between the forward and backward strokes of the feed bars 11 and 12, the eccentric amount of the first eccentric cam 20 with respect to the lower shaft 50 and the eccentric amount of the second eccentric cam 25 with respect to the lower shaft 50 may be adjusted appropriately. Just adjust it. Further, when the eccentric bush 43 is rotated, the feed bar 12 is rotated about the eccentric pin 38, so that the height of the feed dog 16 relative to the feed dog 14 can be adjusted.

As described above, the present invention provides long holes that respectively correspond to the first and second feed tables having the feed dog mounted on the front end thereof, and pin means fixed to the bed to the first and second feed tables. In a differential feed mechanism of a sewing machine in which a first feed table and a second feed table are arranged side by side so as to be relatively displaceable in the front and rear direction by being inserted into a long hole in the feed table, the first feed table is formed in the first feed table. The differential feed of the sewing machine is configured such that the shaft is slidably fitted into another elongated hole, and the eccentric bush fitted into the hole formed in the second feed base is connected to the shaft so as to be relatively rotatable. Since the mechanism is configured, the height of one feed dog can be adjusted with respect to that of the other, which has a great effect.

[Brief explanation of the drawing]

1 is a bottom view of an embodiment of the differential feed mechanism of the sewing machine according to the present invention, FIG. 2 is a side view of the differential feed mechanism of the sewing machine of FIG. 1, and FIG. 3 is a view of the differential feed mechanism of the sewing machine of FIG. 1. FIG. 4 is an exploded perspective view of the differential feed mechanism, FIG. 4 is an exploded perspective view illustrating how the feed dog is attached to the feed base, and FIG. 5 is an exploded perspective view showing how the first eccentric cam and second eccentric cam are attached. A perspective view, and FIG. 6 is a view taken in the direction of arrow A in FIG. 11, 12: Feed base, 14, 16: Feed dog, 3
0, 31: Long hole, 38: Eccentric pin, 40: Long hole,
41: Axis, 42: Hole, 43: Eccentric bush.

Claims (1)

[Claims] 1 The first and second feed dogs are mounted on the front end.
Corresponding long holes are formed in each of the feed tables, and pin means fixed to the bed is inserted into the long holes of the first and second feed tables, so that the first feed table and the second feed table are moved relative to each other in the front-rear direction. In a differential feed mechanism of sewing machines arranged in parallel so as to be displaceable, a shaft is slidably fitted into another elongated hole formed in the first feed table, and a hole formed in the second feed table is provided. A differential feed mechanism for a sewing machine, characterized in that an eccentric bush fitted into the shaft is connected to the shaft so as to be rotatable relative to the shaft.