JPS6114364Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a feed rate adjusting device for a sewing machine.

The conversion mechanism that operates the sewing machine's feed amount adjustment device to convert the sewing machine's feed dog to reverse feed prevents the vibration of the sewing machine's feed dog from being directly transmitted to the feed conversion mechanism, so when the feed amount adjustment device is not operated, the conversion mechanism It is configured so that it is not connected to

For this reason, even if the feed amount is changed, the feed conversion mechanism always returns to the same position, and the operation of the feed conversion mechanism from when the feed conversion mechanism is operated at a different feed amount until the feed dog is activated is necessary. The feed amount changes in response to changes in the feed amount, resulting in an inconsistent operating feel of the feed converting mechanism, which significantly impairs operability.

This invention was created by focusing on these shortcomings, and it is a sewing machine feed that improves operability by ensuring that the amount of operation of the feed conversion mechanism is always a constant amount even when the feed amount changes. The purpose is to provide a conversion mechanism.

An embodiment of this invention will be described below based on the drawings.

In Figure 1, 1 is the machine frame of the sewing machine, 2 is the main shaft that rotates in conjunction with the motor, and 3 is one end of the main shaft 2.
It is a horizontal rod connected to the

4 is a rotating arm rotatably supported on a shaft 5 fixed to the machine frame; 6 is a link rotatably supported on a support shaft 7 provided at the tip of the rotating arm 4; The link 6 constitutes a feed conversion mechanism 8.

The other end of the horizontal rod 3 is rotatably supported on a shaft 8b supported at one end of the link 6.

Reference numeral 9 denotes a horizontal feed shaft that operates in conjunction with a feed dog (not shown) to horizontally move the feed dog, and this horizontal feed shaft 9 is connected to a shaft 8b via a connecting link 10.

Reference numeral 11 denotes a cam body rotatably supported around a shaft 11P supported on the machine frame, and the cam surfaces 11A and 11B are chime-shaped with two curved surfaces.

Reference numeral 12 denotes an operating rod having one end rotatably connected to the support shaft 7 constituting the feed amount conversion mechanism 8 and the other end rotatably connected to the cam body 11.
It is now possible to move between two positions as if moving.

13 is a bulge protruding from the middle of the operating rod 12;
4 is a first spring interposed between the operating rod 12 and the machine frame 1, which pulls the operating rod 12 upward, and the cam body 11
acts to rotate counterclockwise.

Reference numeral 15 denotes a feed converting mechanism rotatably supported on a shaft 16 supported on the machine frame 1, the tip of which protrudes from the machine frame 1, and a second spring 17 interposed between the machine frame and the other end to change the feed. It acts to rotate the conversion mechanism clockwise.

The feed converting mechanism 15 has an arm 18 formed in the middle thereof, the tip of which is opposed to the bulge 13 at a distance.

19 is a feed amount setting dial screwed into the machine frame 1, and the tip portion 19a of this feed amount setting dial 19
are opposed to the cam surfaces 11A and 11B of the cam body 11, the head 16A is exposed outside the machine frame 1, and a slope cam 20 is formed on the back surface of the head 19A.

21 is the screw portion 16B of the feed rate setting dial 16
The pin rod is loosely fitted into the machine frame 1 so as to be movable in parallel with the pin rod, and is arranged so that its left end is in contact with the inclined cam 20.

Reference numeral 22 denotes an adjustment arm rotatably supported on a shaft 23 supported on the machine frame 1, and is formed so that one end is in contact with the right end of the pin rod 21 and the other end is in contact with the top surface of the tip 18a of the arm 18. be.

Therefore, when the dial 16 is rotated and moved in the direction of the screw axis, the pin rod 21 is also moved by the inclined cam 20, and the adjusting arm 20 comes to rotate. The inclined cam 20 is formed so that the distance between the bulge 13 and the tip 18a of the arm 18 is always constant.

Next, the operation of this invention will be explained.

FIG. 1 shows the state of normal feeding.

In this state, the tip 16a of the feed amount adjustment dial 16 is in contact with the cam surface 11A of the cam body 11. To change the feed amount of the feed dog in the normal feed state, the adjustment dial 16 is rotated so that its tip 16a contacts within the range of the cam surface 11A. As a result, the cam body 11 rotates, the operating rod 12 moves in the vertical direction, and the rotating arm 4 is adjusted to rotate around the shaft 5, and serves as a swinging fulcrum for the horizontal rod 3 of the link 6 and the connecting link 10. By adjusting the rotational position of the support shaft 7, the amount of swing of the horizontal feed shaft 9 is changed, and the horizontal momentum of the feed dog is adjusted.

When the adjustment dial 16 is rotated clockwise, the tip 16a moves to the left, and the cam body rotates counterclockwise. As a result, the operating rod 12 moves upward, approaching the bulge 13 and the tip 18a of the arm 18, changing the distance L between the bulge 13 and the tip 18a of the arm 18.

This interval L is determined by the feed conversion mechanism 15 as described later.
Corresponds to the amount of play when operating the feed amount, and if this amount of play changes, the amount of operation of the feed conversion mechanism from when the feed conversion mechanism is operated until the reverse feed is activated will change each time the feed amount is changed. As a result, the operational feel of the feed conversion mechanism is significantly impaired.

However, as described above, when the adjustment dial 16 is rotated clockwise, the cam surface 2 of the adjustment dial 16
0 causes the pin rod 21 to move in the left-right direction, which also causes the adjusting arm 22 to rotate counterclockwise, causing the arm 18 to rotate clockwise and the feed conversion mechanism 15 to also rotate clockwise. .

When the adjustment dial 16 is rotated in this way to change the feed amount, the arm 18 of the feed conversion mechanism 15 also rotates, so the distance L between the bulge 13 and the tip 18a of the arm 18 is kept constant. .

Next, to reverse feed the feed dog, feed conversion mechanism 15
Press down on the tip. Then, the feed conversion mechanism 15 rotates counterclockwise about the shaft 16 against the elastic force of the second spring 17. As a result, the arm 18 also rotates counterclockwise about the shaft 16, and the arm 1
The tip end 18a of the actuating rod 12 contacts and presses the bulging portion 13 of the actuating rod 12, thereby pushing the actuating rod 12 down against the first spring 14. When the operating rod 12 is pushed down, the cam body 11 rotates clockwise about the shaft 11P, and then rotates until the cam surface 11B contacts the tip 16a of the feed amount adjustment dial 16, and then stops. Then, the support shaft 7 provided at the tip of the rotary arm 4 changes its position around the shaft 5 to the reverse feed position.

When the feed amount adjusting dial 16 is rotated to change the amount, the operating rod 12 moves and the bulge 13 and arm 18 are moved.
However, when the feed amount is changed, the arm 18 rotates so that the distance L becomes constant as described above, so the amount of play in the feed conversion mechanism 15 is always constant. The operation feeling of the maintained feed conversion mechanism 15 is not impaired and the operation becomes easier.

FIG. 2 shows another embodiment of this invention, in which an inclined cam 20 is formed in place of the structure in which the adjusting arm 22 is rotated by the inclined cam 20 of the adjusting dial 19 and the pin rod 21 in the previous embodiment. Directly touch the upper end of the adjustment arm 22 to the tip of the threaded part 16B of the adjustment dial 19' that is not connected to the adjustment dial 19'.
The adjustment arm 22 is configured so that the rotation of the arm 9' directly rotates the adjustment arm 22, and even with this configuration, the effects of the above-described embodiment can be obtained.

Note that the configurations of the feed amount conversion mechanism 8 and the feed amount setting dial 19 are not limited to those of the above-mentioned embodiments, and for example, a feed amount conversion mechanism and a feed amount setting dial having a structure as shown in Japanese Utility Model Application Publication No. 51-53160 may be used. In this case as well, the gap between the interlocking body as the operating rod and the second operating body as the feed conversion mechanism is constant according to the movement of the first operating body as the feed amount setting dial. The first operating body and the second operating body may be interlocked via the adjusting arm so that the following is achieved.

As described above, according to this invention, the operating rod that changes the swing fulcrum of the feed amount conversion mechanism in conjunction with the feed rate setting dial is always separated from the operating rod and comes into contact with the operating rod by moving in one direction. A feed conversion mechanism that moves the operating rod and changes the swinging branch of the feed amount conversion mechanism so that the feed dog reversely feeds, and an adjustment arm whose one end is linked to the movement of the feed amount setting dial and whose other end is in contact with the feed conversion mechanism. , so even if the operating rod moves in response to changes in the feed amount of the feed dog using the feed amount setting dial, the adjustment arm will also move a certain distance away from the operating rod according to the amount of movement of the operating rod. It becomes like this.

Therefore, the amount of play in the feed converting mechanism is always a constant amount even if the feed amount of the feed dog is changed, and the operability of the feed converting mechanism is significantly improved, and it is possible to respond to fine sewing operations.

[Brief explanation of the drawing]

FIG. 2 is a sectional view of an embodiment of this invention, and FIG. 2 is a sectional view of another embodiment of this invention. 8...Feed rate conversion mechanism, 9...Horizontal feed axis, 12...
Operating rod, 15...feed conversion mechanism, 19...feed amount setting dial, 22...adjustment arm.

Claims (1)

[Scope of claim for utility model registration] A feed rate setting dial movably supported on the machine frame, a feed rate conversion mechanism that moves to change the feed rate of the feed dog, and a feed rate conversion mechanism that is separated so that the feed rate conversion mechanism can be moved. The actuating rod is always moved between two positions by elastic force, and the actuating rod is always moved to a position corresponding to the movement adjustment of the feed amount setting dial. a feed conversion mechanism that moves against the movement of the feed amount setting dial; A feed amount adjustment device for a sewing machine consisting of an adjustment arm with the other end in contact with a feed conversion mechanism.