JPH03215285A - Cloth feed adjuster of sewing machine - Google Patents

Abstract

PURPOSE:To prevent timing from getting in disorder due to positional deviation and parts from damages by changing a position of the swing center of a first link as an immovable point with an adjusting dial to adjust cloth feed. CONSTITUTION:When an adjusting dial 14 shows the scale O, an adjusting arm 12 and drive arm 8 held respectively nearly horizontally in the longitudinal direction have a pivotal point C at the highest position and are located in positions on nearly longitudinal extension of a horizontal feed rod 9. When a spindle 2 is rotated under such condition, an eccentric cam rod 7 fitted on a horizontal feed cam section 52 of an eccentric cam body 5 has its pivotal point A regulated by the drive arm 8 to move pivotably the horizontal feed cam section 52 while reciprocating (AB-A'B'). Her, when the dial 14 is rotated from the scale 0 to the maximum scale 5, the adjusting arm 12 is pivoted to set the pivotal point C to the lowest position and locate it at a position nearly vertical to the longitudinal direction of the horizontal feed rod 9. When the spindle 2 is rotated under such condition, the pivotal point A of the eccentric cam rod 7 and drive arm 8 reciprocate nearly horizontally (A-A').

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a cloth feed amount adjusting device for an overlock sewing machine, and more particularly to a simple cloth feed amount adjusting device with a mechanism that can be adjusted with a one-touch operation.

[Prior art and inventions or problems to be solved] Generally, the amount of cloth feed in a sewing machine is determined by the horizontal movement of the feed dog, and this horizontal movement of the feed dog is converted into horizontal swing by an eccentric cam fixed to the main shaft. This is achieved by transmitting this horizontal rocking motion to the feed dog via a horizontal feed rod, a horizontal feed drive arm, a feed base, etc.

Conventionally, a mechanism has been proposed to vary the amount of eccentricity of an eccentric cam as an adjustment mechanism for cloth feed in overlock sewing machines (Japanese Patent Publication No. 55-35154, Japanese Patent Application Laid-Open No. 62-1).
70288, Utility Model Publication No. 57-7430).

However, the mechanism like the second one had the disadvantage that it was complicated in structure and difficult to operate.

On the other hand, by changing the pivot point of the horizontal feed rod that swings horizontally to the horizontal drive arm and varying the length of the horizontal feed drive arm, the amount of swing of the horizontal feed drive arm is changed to adjust the amount of cloth feed. Mechanism (Japanese Unexamined Patent Publication No. 1982-192194)
, a mechanism that adjusts the amount of cloth feed by changing the inclination of this adjustment groove, in which the support arm for transmitting the swinging motion of the horizontal feed rod to the horizontal feed shaft is provided with an adjustment groove in combination with a square piece. 189194) has been proposed.

However, the former mechanism was adopted as a sub-feed mechanism for overlock sewing machines with sub-feed teeth, and the main feed is performed by changing the amount of eccentricity of the eccentric cam. Not suitable. The latter mechanism is either an adjustment mechanism for the main feed of Oharron Cumin with a sub-feed Fa groove, or like the former, it is a mechanism combined with a sub-feed mechanism, so it is difficult to determine whether the mechanism as a whole is combined or not. When making adjustments, it was necessary to change part of the sewing machine's power transmission system, so it was necessary to stop the sewing machine and operate it. For example, after operating the push button at one point in one rotation of the sewing machine and unlocking the adjustment mechanism, it is necessary to operate the handwheel, knob, etc. to complete the feed cycle, and the push button does not return to the safe position. There have been cases where the sewing machine has been rotated and the timing of the feed mechanism has been misaligned, making it impossible to sew, or the sewing machine has malfunctioned in order to avoid damaging parts.

In addition, these conventional cloth feed amount adjustment mechanisms generally require a combination of two or three operations, such as loosening a fixing screw, adjusting with an adjustment knob, adjustment lever, etc., and then tightening the screw again, and cannot be adjusted by one-touch operation. Ta.

[Object of the Invention] The present invention solves these conventional problems and provides a new method that can convert the horizontal momentum of the feed dog by moving the position of the fixed point that does not move in the power transmission system. To provide a cloth feed adjustment device which can be operated without stopping a sewing machine and eliminates failures due to erroneous operation.

A further object of the present invention is to provide an easy-to-operate feed decoy adjustment device that allows the feed amount to be easily set with a one-touch operation by adjusting the feed adjustment dial according to the displayed feed scale.

U Means for Solving the Problems The cloth feed amount adjusting device of the present invention that achieves the above object includes a horizontal feed cam portion fixed to the main shaft and eccentric from the main shaft, and a horizontal feed cam portion that is rotatable to the horizontal feed cam portion. a fitting member that is fitted into the horizontal feed cam portion and swings as the horizontal feed cam portion rotates; and a fitting member that is connected to a portion of the fitting member at a first connection point and swings as the fitting member swings. a second link member that is connected to a second connection point of the first link member and that horizontally reciprocates as the first link member swings;
The first link member includes a feed arm that swings in accordance with the horizontal reciprocating motion of the second link member, and a feed base that has a feed tooth that swings in response to the swing of the feed arm, and the first link member The third link member is connected to one end side at a connecting point and is swingable about the third connecting point, and the third link member has an adjustment dial fixed to the other end side and is connected to one end side of the third link member. By rotating the third link member using the adjustment dial and moving the position of the center of swing of the first link member, the swing of the first link member can be adjusted. The feed amount of the feed base can be adjusted by changing the moving direction.

[Operation] When the main shaft rotates, the rotational motion is converted by the horizontal feed cam fixed to the main shaft, and the fitting member that fits into the horizontal feed cam and the first link member pivotally attached to a part of the fitting member are swung. make it move. This oscillating movement of the first link member is transmitted to the second link member and further transmitted via the horizontal feed arm to the feed base provided with the feed dog.

Here, the first link member is pivotally connected to the third link member at its third connection point, and swings about the pivot point. The direction in which the first link member swings around this pivot point changes as the position of the pivot point with respect to the horizontal feed cam changes. That is, when the position of the pivot point changes, the swinging direction of the connection point between the first link member and the second link member also changes, thereby changing the amount of swing of the second link member in the horizontal direction. Therefore, when the swing center (pivot point with the third link member) is located so that the first link member swings in a substantially vertical direction, the second link member has a horizontal direction. No rocking motion is given and the feed arm is not rocked. Therefore, the amount of rocking of the feed base becomes minimum (zero). Furthermore, when the first link member is positioned such that the center of swing is located so that the first link member swings in a substantially horizontal direction, the second link member swings in accordance with the swing of the first link member, and the second link member swings in accordance with the swing of the first link member. Motion 1 is maximum. Therefore, the amount of swing of the feed base that swings via the feed arm becomes maximum.

By selecting the feed scale with the feed dial, the third link member rotates as the feed dial rotates, and the pivot point between the third link member and the first link member, that is, the pivot point of the first link member, is rotated. The pivot center is moved and positioned. As a result, the amount of momentum of the swinging feed base can be adjusted via the second link member and the feed arm.

Here, since the pivot point between the first link member and the third link member is a fixed point on which the power transmission system does not act, the position of this fixed point can be moved without stopping the sewing machine (power transmission system). It can be carried out.

[Example] Hereinafter, the cloth feed amount adjusting device for a sewing machine according to the present invention will be described based on an example.

FIG. 1 is an overall view of a small overlock sewing machine to which the fabric feed rate adjusting device of the present invention is applied. A feed mechanism and a feed adjustment mechanism for driving are attached.

FIG. 2 shows an exploded perspective view of these feed mechanisms and feed adjustment mechanisms.

The feed mechanism mainly includes an eccentric cam body 5 fixed to the main shaft 2, a vertical feed link 6 that fits into a vertical feed cam portion 51 of the eccentric cam body 5, and a fitting link that fits into a horizontal feed cam portion 52 of the cam body 5. The eccentric cam rod 7 which is a member, the drive arm 8 which is a first link member, the horizontal feed rod 9 which is a second link member, and one end 101 is connected to the horizontal feed rod 9 and swings around the axis 1. It consists of a horizontal feed arm 10 and a feed upper table 4 connected to the other end 102 of the feed arm 10.

The feed adjustment mechanism mainly uses the horizontal feed cam portion 52 of the cam body 5.
an eccentric cam rod 7 that fits into the eccentric cam rod 7; and first and second connecting portions 8 on each of the eccentric cam rod 7 and the horizontal feed rod 9;
1 and 82 (pivot points A, B), and the drive arm 8 is connected to the third connection part 83 (pivot point C), and the pivot point C, which is the center of swing, It consists of an adjustment arm 12 as a third link member for changing the position, and an adjustment dial 14 fixed to a pin 122, which is the center of rotation of the adjustment arm 12.

The eccentric cam body 5 has a vertical feed cam part 51 and a horizontal feed cam part 52 integrally molded, and is screwed and fixed to one end of the main shaft 2. The vertical feed cam section 51 is eccentric with respect to the king shaft 2 and converts the rotational motion of the main shaft 2 into vertical swinging motion, and the horizontal feed cam section 52 is eccentric with respect to the main shaft 2 and converts the rotational motion of the main shaft 2 into horizontal swinging motion. Convert to dynamic motion.

A portion of the vertical feed link 6 is rotatably connected to the vertical drive unit 41 of the upper feed table 4 by an eccentric pusher 13.
The vertical swing motion converted by the vertical feed cam portion 51 is transmitted to the feed base 4. Incidentally, the eccentric push 13 can adjust the vertical position of the feed dog 3.

The eccentric cam rod 7 is rotatably fitted into the horizontal feed cam portion 52 and is held down by the thrust receiver 15 so as not to come off from the horizontal feed cam portion 52. The signal is transmitted to the drive arm 8. The thrust receiver 15 is screwed to the horizontal feed cam portion 52. Further, a drive arm 8 is pivotally attached to a portion 71 of the eccentric cam rod 7 by a shaft 16.

The drive arm 8, which is the first link member, includes an eccentric cam rod 7,
First, second and third connecting portions 81, 82, 83 for connecting to the horizontal feed rod 9 and the adjusting arm 12, respectively
As already mentioned, the connecting part 81 is pivotally connected to the eccentric cam rotor 7, and the connecting part 82 closer to this connecting part 81 has horizontal feed points. The rond 9 is pivotally mounted by a stepped screw 17. The connecting portion 83 has an adjusting arm 12 (to be described later) or a pin 12 provided vertically on the adjusting arm 12.
connected by 1. A pivot point C, which is the center of this connecting portion 83, becomes the center of swing of the drive arm 8.

The horizontal feed rod 9, which is a second link member, has one end connected to the lower end 101 of the horizontal feed arm 10 by a connecting pin 18, and moves horizontally reciprocating in response to the swinging of the drive arm 8, and swings to the horizontal feed arm 10. Give exercise.

The horizontal feed arm 10 is swingably supported on the sewing machine body by a shaft 11, and the horizontal drive portion 42 of the feed base 4 is connected to the upper end side 102 via a shaft 19. Its lower end side 10
1 is swung by the horizontal feed rod 9, the upper end side 102
are interlocked and oscillate to give the feed base 4 a oscillating motion in the horizontal direction.

The feed base 4 performs an elliptical movement as a result of the vertical movement imparted to its vertical drive 41 by the vertical feed link 6 and the horizontal movement imparted to its horizontal drive 42 by the horizontal feed arm 10.

Next, the adjusting arm 12 which is the third link member has two bins 121 and 122 erected in opposite directions on both ends thereof, and the bin 121 on one end side is connected to the connecting part 8 of the drive arm 8.
3 (pivot point C). Further, the pin 122 at the other end is pivotally supported by the sewing machine body, and the hinge arm 12 rotates around this pin 122. The adjustment dial 14 is connected to the wave washer 20 on the part of the pin 122 that protrudes outside the sewing machine body.
has been fixed through. Furthermore, the adjustment arm 12 is provided with a notch 123 having a size corresponding to the scale width of the adjustment dial 14 at its upper end. A stopper 21 fixed to the sewing machine body engages with this notch 123 to limit the operating range of the adjustment dial 14, that is, the rotation range of the adjustment arm 12.

The operation of the feed mechanism and the feed adjustment mechanism in the above configuration will be explained.

First, when the adjustment dial 14 is at 0, the longitudinal direction of the adjustment arm 12 and the drive arm 8 is approximately horizontal (Fig. 3), and the pivot point C of the adjustment arm 12 and the drive arm 8 is Located in the highest position. Here, when the scale is sequentially rotated from the scale O to the maximum scale 5, for example, the pin 122 of the adjustment arm 12 fixed to the adjustment dial 14 rotates at the same time, causing the adjustment arm 12 to rotate. This rotation moves the pin 121 downward, and moves the position of the pivot point C between the adjusting arm 12 and the driving arm 8. This movement of the adjustment dial 14 is stopped by a stopper 21 at the maximum scale 5 (FIG. 5).

When the adjustment dial 14 is at scale O, as shown in FIG. is positioned. When the main shaft 2 rotates in this state, the horizontal feed cam portion 52 of the eccentric cam body 5 moves eccentrically, but the pivot point A of the eccentric cam rod 7 fitted to the horizontal feed cam portion 52 is aligned with the drive arm 8. 5, the horizontal feed cam section 52 freely rotates and performs a reciprocating motion (AB-A''B'') as shown in FIG. Here, drive arm 8
Since the pivot point C, which is the pivot point, is positioned at a high position approximately horizontal to the pivot point A by the adjustment arm 12,
Swing motion of pivot point A and pivot point B (A-A', B-B'
) are performed in the substantially vertical direction.

As a result, the horizontal feed rod 9 swings at the pivot point B, but does not move at the connecting portion 101 (point D) with the feed arm 10.

Therefore, since the feed arm 10 also does not move, no horizontal movement is applied to the feed base 4, and the cloth feed amount becomes zero.

Next, when the adjustment dial 14 is at its maximum scale, the pivot point C between the adjustment arm 12 and the drive arm 8 is at the lowest position relative to the longitudinal direction of the horizontal feed rod 9, as shown in FIG. It is positioned in a substantially vertical position. When the main shaft 2 rotates in this state and the eccentric cam rod 7 fitted to the horizontal feed cam portion 52 moves, the pivot point A between the eccentric cam rod 7 and the drive arm 8 will move approximately as shown in FIG. Make a horizontal reciprocating motion (A-A'). That is, the pivot point B between the drive arm 8 and the horizontal feed rod 9 also swings in the substantially horizontal direction, so that the horizontal feed rod 9 performs the maximum swing movement (D-D') in the substantially horizontal direction. do. The feed arm 10 swings around point E, giving the feed base 4 the maximum horizontal movement 1 (F-F').
give.

[Effects of the Invention] As is clear from the above embodiments, according to the cloth feed device of the sewing machine of the present invention, the eccentric cam rod extracts the horizontal movement from the horizontal eccentric cam, and the horizontal First and second links are provided between the feed arm and the position of the swing center of the first link, which is a fixed point, is changed using an adjustment dial, and the feed amount is adjusted by this, so the sewing machine is stopped. Even if the sewing machine (main shaft) rotates during operation by mistake, the feed mechanism will not be misaligned, and the timing will be off due to misalignment, making it impossible to sew or damaging parts. Accidents can be prevented.

Furthermore, according to the fabric feed adjustment device for a sewing machine of the present invention, the feed can be adjusted with one touch by simply adjusting the adjustment dial according to the displayed scale, and even beginners can operate it extremely easily.

[Brief explanation of drawings]

Fig. 1 is an overall perspective view of a small overlock sewing machine to which the fabric feed amount adjustment device of the sewing machine of the present invention is applied, Fig. 2 is an exploded perspective view showing the feed reduction node tlhlll, and Figs. 3 and 4 are respectively Side views of the feed adjustment device in different adjustment positions, FIGS. 5 and 6, each showing the operation of the feed mechanism in different adjustment positions. 2...Main shaft 3...Feed dog 4...Feed base 5...Eccentric cam body 52...Horizontal feed cam section 6... Vertical feed link 7... Eccentric cam rod (tT: joining part) 8.
...... Drive arm (first link member) 81, 82,
83 ・・・・・・First, second, third connection point・・・・・・
・Water sheep feeder (second link member) 0...Feeding arm 2...Adjustment arm (third link member) 4...
adjustment dial

Claims (1)

[Claims] a horizontal feed cam portion fixed to the main shaft and eccentric from the main shaft; a fitting member that rotatably fits into the horizontal feed cam portion and swings as the horizontal feed cam portion rotates; and the fitting member a first link member connected to a part of the fitting member at a first connection point and swings as the fitting member swings; and a first link member connected to a second connection point of the first link member and said first link member. a second link member that horizontally reciprocates as the link member swings; a feed arm that swings as the second link member swings horizontally; and a feed arm that swings as the feed arm swings. a feed base having a feed dog; the first link member is connected to one end side of the third link member at a third connection point thereof and is swingable about the third connection point; The third link member has an adjustment dial fixed to its other end and is rotatable around the other end, and when the third link member is rotated by the adjustment dial, the adjustment dial is fixed to the other end. A fabric feed amount adjusting device for a sewing machine, characterized in that the feed amount of the feed base can be adjusted by changing the swing direction of the first link member by moving the position of the swing center of the member.