JP2000225280A - Feed dog adjusting mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism which can easily and moreover finely adjust the height of a feed dog. SOLUTION: The mechanism is provided with the feed dog 8 given four feeding movement by a horizontal feeding axis 2 and a vertical feeding axis 4 linked with the main axis of a sewing machine, a feed bar having a horizontal part and supporting the feed dog at the horizontal part, a first connecting member 54 connected to the vertically feeding axis, a second connecting member 56b whose one end is connected to the first connecting member through an eccentric member 58 and the other end of which is connected to the horizontal part of the feed bar. By rotating the eccentric member, the height of the feed dog can be adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a feed dog height adjusting mechanism for a sewing machine.

[0002]

2. Description of the Related Art FIG. 6 shows a feed dog mechanism of a conventional sewing machine. The feed dog mechanism 1 is for a two-needle horizontal hook sewing machine. In the figure, a feed dog mechanism 1 includes a horizontal feed shaft 2,
It has a vertical feed shaft 4 and a feed base 6. Both the horizontal feed shaft 2 and the vertical feed shaft 4 are rotatable in conjunction with a main shaft (not shown) of the sewing machine. The feed base 6 has a horizontal portion 6a extending in the horizontal direction and a vertical portion 6b extending in the vertical direction.
The feed dog 8 is supported by a.

The horizontal portion 6a of the feed bar 6 is provided with a horizontal feed shaft 10
By being connected to the horizontal feed shaft 2 via the horizontal feed arm 12, the feed base 6 moves in the horizontal direction with the rotation of the horizontal feed shaft 2. On the other hand, the vertical portion 6b of the feed base 6 is connected to the vertical feed shaft 4 via the vertical feed arm 14 and the vertical feed cam 16, so that the feed base 6
It moves up and down with the rotation of. Thus, the feed dog 8 moves vertically and horizontally while drawing an elliptical locus.

The upper and lower feed arms 14 have a groove 14a formed in a connection portion with the vertical portion 6b of the feed base 6, and this groove 14a is formed.
The vertical portion 6b of the feed base 6 is fitted into the position a, and the feed base 6 and the upper and lower feed arms 14 are connected and fixed by the screws 18.

FIGS. 8 and 9 show the feed dog mechanism 1 of FIG.
It is a figure for roughly showing the position where it is installed in the sewing machine of this needle horizontal shuttle when it is installed. FIG. 8 is a front view, in which the feed dog mechanism 1 is viewed from the direction of arrow A in FIG. 6, and FIG. 9 is a bottom view. In this case, the feed dog mechanism 1 is viewed from the direction of arrow B in FIG. This is the view you saw. Two shuttle shaft heads 20 are fixed to the sewing machine and are juxtaposed as shown. A shuttle shaft 22 is rotatably attached to each shuttle shaft stand 20, and a horizontal shuttle 24 is mounted on an upper end of each shuttle shaft 22.
A hook shaft gear 26 is fixed to each hook shaft 22. Also,
A lubricating oil tube 27 for supplying lubricating oil to the horizontal hook 24 via a lubricating oil path (not shown) in the hook shaft 22 is connected to the shuttle shaft stand 20. This shuttle shaft stand 20, shuttle shaft 22,
The horizontal hook 24, the hook shaft gear 26, the lubricating oil tube 27, and other components (not shown) constitute a hook shaft unit 28.

FIG. 10 is a view showing an example of the feed dog mechanism 31 of the lockstitch sewing machine. Horizontal feed shaft 32 and vertical feed shaft 34
Rotate together with the main shaft of the sewing machine (not shown). A feed base 36 supporting a feed dog 38 at the center is connected at one end to the horizontal feed shaft 32 via the horizontal feed shaft 10 and the horizontal feed arm 40, and at the other end to the vertical feed shaft 11 and the vertical feed arm 42. Is connected to the vertical feed shaft 34 via
As described above, the vertical feed arm 42 connecting the vertical feed shaft 34 and the feed base 36 or the horizontal feed arm 40 connecting the horizontal feed shaft 32 and the feed base 36 are both extremely long with respect to the length of the feed base 36. It is usually short.

[0007]

It is sometimes necessary to adjust the height of the feed dog 8 in accordance with the type of the material to be sewn. In particular, in the case of a thin and soft sewn material such as underwear or the like, slippage easily occurs when the cloth is fed by the feed dog 8, so that it is often necessary to finely adjust the height of the feed dog 8.

The feed dog mechanism 1 shown in FIG. 6 can adjust the height of the feed dog 8 due to its configuration. That is, the feeder 6
The height of the feed dog 8 is determined by loosening the screw 18 connecting the vertical feed arm 14 and the vertical portion 6b in the groove 14a of the vertical feed arm 14 up and down, and tightening the screw 18 again. The height of the feed dog 8 can be adjusted. However, as shown in FIGS. 8 and 9, both the vertical portion 6b that needs to be slid and the screw 18 that needs to be tightened and loosened are located between the two shuttle shaft head units 28, and two Since it is necessary to perform the adjustment work at the place where each part of the headstock unit 28 is intricate, the adjustment work is very difficult. For this reason, it was practically impossible to adjust by such a method. Further, in the method in which the vertical portion 6b of the feed dog mechanism 1 is slid, the height of the feed dog 8 cannot be finely adjusted.

For this reason, as shown in FIG. 7, the height of the feed dog 8 is adjusted by interposing a sheet 30 of an appropriate thickness, for example, paper, between the feed dog 8 and the feed table 6.

An object of the present invention is to provide a mechanism capable of easily adjusting the height of the feed dog. Still another object of the present invention is to provide a mechanism capable of finely adjusting the height of the feed dog. Still other objects of the present invention will become apparent from the following description.

[0011]

According to the present invention, a feed dog provided with four feed motions by a horizontal feed shaft and a vertical feed shaft interlocking with a main shaft of a sewing machine is provided. A feed base having the feed dog at a horizontal portion thereof, a first connecting member connected to the vertical feed shaft,
One end is connected to the first connection member via an eccentric member,
A second connecting member having the other end connected to the horizontal portion of the feed table, wherein the height of the feed dog can be adjusted by rotating the eccentric member. An adjustment mechanism is provided.

The second connecting member is, for example, a vertical portion fixed to the feed base. Preferably, the horizontal part of the feed base supports the feed dog near the connection with the vertical part. Further, for example, the sewing machine is a two-needle horizontal shuttle sewing machine, and the feed dog height adjusting mechanism is disposed between the two shuttle shaft head units. Preferably, the eccentric member is located near the lower ends of the two shuttle shaft head units.

[0013]

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

FIG. 1 shows a feed dog mechanism having a feed dog height adjusting mechanism of the sewing machine according to the present embodiment, and FIG. 2 is a simplified diagram for explaining the principle of adjusting the feed dog height in the mechanism of FIG. FIGS. 3, 3 and 4 are views for schematically showing a position where the feed dog mechanism of FIG. 1 is incorporated into the two-needle horizontal shuttle sewing machine, and FIG. 3 is a front view. FIG. 4 is a bottom view, and the feed dog mechanism in this case is a view seen from the direction of arrow B in FIG.

In these figures, the feed dog mechanism 51 has a horizontal feed shaft 2, a vertical feed shaft 4, and a feed base 56. Both the horizontal feed shaft 2 and the vertical feed shaft 4 are rotatable in conjunction with a main shaft (not shown) of the sewing machine. The feed base 56 has a horizontal portion 56a extending in the horizontal direction and a vertical portion 56b extending in the vertical direction.
(Second connecting member), and the horizontal portion 56a supports the feed dog 8 near the connection portion with the vertical portion 56b. The vertical portion 56b extends vertically downward while slightly bending.

The horizontal portion 56a of the feed bar 56 is connected to the horizontal feed shaft 2 via the horizontal feed bar shaft 10 and the horizontal feed arm 12, whereby the feed bar 56 moves in the horizontal direction with the rotation of the horizontal feed shaft 2. Exercise. Vertical part 56b of feed bar 56
Is connected to a vertical feed arm 54 (first connecting member) via an eccentric shaft 58 that supports the both ends, and the vertical feed arm 54 is connected to the vertical feed shaft 4 via a vertical feed cam 16, whereby The feed table 56 moves up and down with the rotation of the vertical feed shaft 4.

In this manner, a four-feed motion of the feed dog is provided. The four-feed motion of the feed dog is a motion in which the feed dog 8 comes out on the upper surface of the needle plate (not shown) while drawing an elliptical locus, advances on the upper surface of the needle plate, sinks on the lower surface of the needle plate, and retracts on the lower surface of the needle plate.

The eccentric shaft 58 is fastened and fixed to the upper and lower feed arms 54 by screws 60. When adjusting the height of the feed dog 8, the screw 60 is loosened, a screwdriver is inserted into a groove (not shown) provided in the head of the eccentric shaft 58, rotated by an appropriate angle, and then the screw 60 is tightened again. FIG.
When the eccentric shaft 58 is rotated so that the eccentric portion is located at the lowermost position as shown in FIG. 7A, and the eccentric shaft 58 is tightened and fixed to the upper and lower feed arms 54 with the screw 60, the height of the feed dog 8 is also adjusted to the lowermost position. Is done. On the other hand, when the eccentric part of the eccentric shaft 58 is adjusted to be located at the uppermost position as shown in FIG. 2B, the height of the feed dog 8 is also adjusted to the uppermost position.

As described above, according to the feed dog height adjusting mechanism of the present embodiment, the feed dog height can be adjusted by a simple operation. Since the amount of eccentricity is adjusted by rotating the eccentric shaft 58, fine adjustment is possible as compared with the conventional slide method.

The shuttle shaft stand 20, the shuttle shaft 22 of FIGS.
The arrangement of the hook shaft unit 28 having the horizontal hook 24, the hook shaft gear 26 and the lubricating oil tube 27 is the same as that in FIGS. 8 and 9, but the screw 60 of the feed dog mechanism of the present embodiment is used.
The eccentric shaft 58 is located near the lower end of the shuttle shaft stand unit 28, and the operating portion (head) side of the screw 60 is directed to the side slightly protruding from between the two shuttle shaft stand units 28, so that it is loosened. Easy to tighten and tighten. Furthermore,
The eccentric shaft 58 is located at a position where it is easy to operate similarly to the screw 60, and unlike the conventional slide method of FIGS. 6 to 9, it is sufficient to simply rotate the eccentric shaft 58. Adjustment work can be performed.

In order to adjust the height of the feed dog 8, when the relative positional relationship between the vertical portion 56b, the connecting portion (eccentric shaft 58) of the vertical feed arm 54 and the vertical feed shaft 4 is changed, the feed dog 8 Also changes. For example, in the stationary state of the sewing machine, as a result of changing the direction and the amount of eccentricity of the eccentric shaft 58,
Assuming that the upper and lower feed arms 54 rotate around the vertical feed shaft 4 by θ degrees, as a result of this rotation, the feed locus of the feed dog 8 changes during the operation of the sewing machine. As a matter of course, the degree of the change increases as the angle θ increases.

For example, a feed dog mechanism 31 as shown in FIG.
When the position of the vertical feed shaft 11 is changed up and down to change the relative positional relationship between the vertical feed shaft 34 and the vertical feed shaft 11, the vertical feed arm 42
Rotate α degrees around 4. In this case, since the length of the upper and lower feed arms 42 is short, the above-mentioned angle α becomes large, and the feed dog 3
8 is easy to change greatly.

However, in the feed dog height adjusting mechanism of the feed dog mechanism 51 according to the present embodiment, the distance between the vertical feed shaft 4 and the eccentric shaft 58 is relatively long, so that the length of the vertical feed arm 54 is long. Therefore, a change in the rotation angle θ of the upper and lower feed arms 54 with respect to the direction of the eccentric shaft 58 and the magnitude of the amount of eccentricity is reduced. As a result, the change of the feed locus of the feed dog 8 becomes small.

FIG. 5 is a diagram for explaining the magnitude of the change in the height of the feed dog 8 when the amount of eccentricity by the eccentric shaft 58 is changed by the feed dog height adjusting mechanism of the present embodiment. In the figure, the vertical feed arm 5 by the rotation of the eccentric shaft 58 is shown.
X, the vertical displacement of the feed dog 8 is y, the horizontal distance between the eccentric shaft 58 and the center of the horizontal feed shaft 10 is L1, the feed dog 8 Assuming that the horizontal distance between the horizontal feeder shaft 10 and the center is L2, y
= XL2 / L1. Therefore, by making L1 closer to L2, the value of y for a certain x can be increased.

In the feed dog height adjusting mechanism according to the present embodiment, the feed base 56 is formed of a horizontal portion 56a and a vertical portion 56b integrally fixed to the horizontal portion 56a. Since the feed dog 8 is supported near the connection with the portion 56b, it is possible to bring L1 closer to L2. It should be noted that L1 can be made closer to L2 by reducing the curvature of the vertical portion 56b to make it more linear.

In the case of the feed dog mechanism 31 of the lockstitch sewing machine shown in FIG. 10, the change in the height of the feed dog 38 when the height of the upper and lower feed shafts 11 is changed by x by any method is represented by y. , The distance between the horizontal feed shaft 10 and the vertical feed shaft 11 is L1, and the distance between the feed dog 38 and the horizontal feed shaft 10 is L2.
Then, similarly to the above, y = xL2 / L1. In the case of the illustrated feed dog mechanism 31, since L2 is about の of L1, y is also about の of x.

Further, in the mechanism shown in FIG. 10, when the height of the vertical feed shaft 11 is changed, the movement of the feed dog 8 is changed not only in the vertical direction but also in the horizontal direction. In the case of the feed dog height adjusting mechanism according to the present embodiment, the upper and lower feed arms 5
4 is transmitted to the feed base 56 via the vertical portion 56b, so that even if the height of the eccentric shaft 58 is adjusted, the movement of the feed dog 8 hardly changes in the horizontal direction.

[0028]

According to the feed dog height adjusting mechanism of the present invention,
A feed base having a horizontal portion and supporting the feed dog at the horizontal portion, a first connecting member connected to the vertical feed shaft, and one end connected to the first connecting member via an eccentric member; A second connecting member whose end is connected to the horizontal portion of the feed table, and the height of the feed dog can be adjusted by rotating the eccentric member. Can be adjusted, and fine adjustment is possible.

Further, in the feed dog height adjusting mechanism according to the present invention, since the feed base is formed of a horizontal part and a vertical part fixed to the horizontal part, the feed base is formed from a connection point between the horizontal feed arm and the feed base. The horizontal distance to the eccentric shaft can be made closer to the horizontal distance between the feed dog and the horizontal feed base shaft, so that the ratio of the height adjustment amount of the feed dog to the eccentric amount by the eccentric member can be increased. .

Furthermore, the horizontal portion of the feed base supports the feed dog near the connection with the vertical portion, thereby determining the horizontal distance from the connection point between the horizontal feed arm and the feed base to the eccentric shaft and the feed dog and the horizontal position. It is possible to further approach the horizontal distance between the feed shaft and the feed shaft, so that the ratio of the height adjustment amount of the feed dog to the eccentric amount by the eccentric member can be further increased.

When the feed dog height adjusting mechanism of the present invention is incorporated into a two-needle horizontal hook sewing machine, and the feed dog height adjusting mechanism is disposed between the two hook shaft head units, the eccentric member is moved to the first position.
The fixing means and the fixing means for fixing to the connecting member can be arranged near the lower end portions of the two shuttle shaft head units, so that the fixing means and the eccentric member are located at positions that are easy to operate, and unlike the conventional slide method, Since the eccentric member only needs to be rotated, the adjusting operation can be easily performed even in a narrow place.

[Brief description of the drawings]

FIG. 1 is a diagram showing a feed dog mechanism having a feed dog height adjusting mechanism according to an embodiment of the present invention.

FIG. 2 is a simplified diagram for explaining the principle of adjusting the height of a feed dog in the mechanism of FIG.

FIG. 3 is a front view schematically showing a position where the feed dog mechanism of FIG. 1 is incorporated into the two-needle horizontal shuttle sewing machine.

FIG. 4 is a side view schematically showing a position where the feed dog mechanism of FIG. 1 is incorporated into the two-needle horizontal shuttle sewing machine.

5 is a diagram for explaining the magnitude of change in the height of the feed dog when the amount of eccentricity by the eccentric shaft is changed by the feed dog height adjusting mechanism in FIG. 1;

FIG. 6 is a view showing a feed dog mechanism according to a conventional example.

7 is a diagram showing a method of adjusting the height of a feed dog in the mechanism of FIG.

FIG. 8 is a front view schematically showing a position where the feed dog mechanism of FIG. 6 is incorporated when the feed dog mechanism is incorporated into a sewing machine of a two-needle horizontal shuttle.

FIG. 9 is a bottom view for schematically showing a position where the feed dog mechanism of FIG. 6 is incorporated into a two-needle horizontal shuttle in a sewing machine.

FIG. 10 is a diagram illustrating an example of a feed dog mechanism of the lockstitch sewing machine.

[Explanation of symbols]

1 feed dog mechanism 2 horizontal feed shaft 4
Vertical feed shaft 6 Feed stand 6a Horizontal part 6
b Vertical part 8 Feed dog 10 Horizontal feed shaft 1
DESCRIPTION OF SYMBOLS 1 Vertical feed stand axis 12 Horizontal feed arm 14 Vertical feed arm 1
4a Groove 16 Vertical feed cam 18 Screw 2
0 Hook shaft 22 Hook shaft 24 Horizontal hook 2
6 Hook shaft gear 27 Lubricating oil tube 28 Hook shaft base unit 3
0 sheet piece 31 feed dog mechanism 32 horizontal feed shaft 3
4 vertical feed shaft 36 feed base 38 feed dog 4
0 horizontal feed arm 42 vertical feed arm 51 feed dog mechanism 54 vertical feed arm (first connecting member) 5
6 feed base 56a horizontal part 56b vertical part (second connecting member) 58 eccentric shaft 60 screw

Claims (5)

[Claims] A feed dog provided with four feed motions by a horizontal feed shaft and a vertical feed shaft interlocked with a main shaft of a sewing machine; a feed base having a horizontal portion and supporting the feed dog at the horizontal portion; A first connecting member connected to the vertical feed shaft; one end connected to the first connecting member via an eccentric member;
A second connecting member having the other end connected to the horizontal portion of the feed table, wherein the height of the feed dog can be adjusted by rotating the eccentric member. Adjustment mechanism. 2. The feed dog height adjusting mechanism according to claim 1, wherein said second connecting member is a vertical portion fixed to said feed table. 3. The feed dog height adjusting mechanism according to claim 1, wherein the horizontal portion of the feed base supports the feed dog near a connection with a vertical portion. Adjustment mechanism. 4. The feed dog height adjusting mechanism according to claim 1, wherein said sewing machine is a two-needle horizontal hook sewing machine, and said feed dog height adjusting mechanism comprises two hooks. A feed dog height adjusting mechanism, which is arranged between the headstock units. 5. The feed dog height adjusting mechanism according to claim 4, wherein said eccentric member is arranged near a lower end of said two hook shaft head units. .