JPH063272U - Automatic presser lifting device - Google Patents

Abstract

(57) [Summary] [Purpose] To be able to change the amount of lifting of the work clamp according to the upper and lower stop positions of the needle bar. [Structure] A stopper 6 is provided for limiting the movement of a presser foot lifting solenoid 2 when the sewing machine is stopped under the sewing machine in conjunction with the rotation of the sewing machine.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sewing machine, and more particularly to an automatic presser lifting device that automatically raises a work clamp when a needle bar of an automatic thread trimming sewing machine is stopped.

[0002]

[Prior art]

 Generally, the lifting and lowering of the presser foot of the sewing machine is performed by raising the knee, but instead of this, an actuator such as an electromagnetic solenoid or an air cylinder is automatically used.

[0003]

[Problems to be solved by the device]

 Unlike the conventional method of automatically raising the presser foot using an actuator, it is impossible to finely adjust the amount of increase, unlike the raising of the presser foot caused by a human knee raising operation. In an automatic thread trimmer sewing machine, the needle bar stops at two positions: an upper stop position where the cloth can be put in and taken out under the presser foot and a lower stop position where the sewing material can be rotated around the needle as a fulcrum. , When the needle bar is stopped downward, the needle bar is in the lower position, so the work clamp raised by the operation of the automatic presser lifting device interferes with the needle bar and the needle bar thread hook. In order to prevent this, it is necessary to adjust the lift amount of the work clamp, but as described above, in the conventional device, the lift amount cannot be changed depending on the upper stop position and the lower stop position.

An object of the present invention is to provide an automatic presser lifting device capable of changing the amount of lift of the presser foot corresponding to the upper stop position and the lower stop position of the needle bar.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the automatic presser lifting device of the present invention is provided with a stopper that limits the movement of the presser lifting solenoid when the sewing machine is stopped under the condition of interlocking with the rotation of the sewing machine.

[0006]

[Work]

 In the automatic presser lifting device configured as described above, the maximum amount of lift of the work clamp corresponding to the movement stroke of the presser foot lifting solenoid is achieved when the sewing machine is stopped, and when the sewing machine is stopped, it is restricted by the stopper. A small amount of lifting of the work clamp corresponding to the movement stroke of the presser foot lifting solenoid is performed.

[0007]

【Example】

 An embodiment of the present invention will be described with reference to FIGS. 1 to 5 by taking an automatic presser lifting device of a type in which a presser lifting solenoid 2 is attached to a window plate 1 at the rear of a sewing machine.

This automatic lifting device is roughly composed of a solenoid arm 3 which is rotated by an electromagnetic solenoid 2 fixed to the outside of a window plate 1 at the rear of the sewing machine, a topper 4 fixed to the solenoid arm 3, and an upper part. It is composed of a stopper arm 6 fixed to the shaft 5 and a presser bar 8 having a cloth presser 7 connected to the solenoid arm 3 via a plurality of members such as links.

As shown in FIG. 4, the solenoid arm 3 is fixed to one end of a rotating shaft 9 supported by a frame, and the other end of the rotating shaft 9 has a rod 1 of the electromagnetic solenoid 2 at its other end. The other end of the lever 11 pivotally attached to the bifurcated part of 0 is fixed. Therefore, when the electromagnetic solenoid 2 is actuated to extend the rod 10, the solenoid arm 3 is rotated clockwise through the lever 11 and the rotation shaft 9.

The stopper 4 is made of a plate body bent in an L shape, and is provided on the right side of the vicinity of the turning end of the solenoid arm 3 so as to project as shown in FIG.

The stopper arm 6 has an arm 6 a protruding in one direction, and is fixed to the rear of the feed cam 12 fixed to the upper shaft 5. The arm 6a is set to face the window plate 1 when the sewing machine is stopped below.

A solenoid link 13 is rotatably connected to the solenoid arm 3, and a long hole 13 a at the other end of the solenoid link 13 projects from a knee lift link 15 rotatably supported by a support shaft 14. The pin 16 provided is inserted. One end of a knee-raising connecting rod 17 is rotatably connected to the pin 16, and the other end of the knee-raising connecting rod 17 is L-shaped and rotatably supported by a fulcrum 18 of the frame. One arm 20 of the link 19 is rotatably connected. A lifting plate 22 is attached to the other arm 21 of the link 19. On the other hand, the presser bar hanger 23 is fixed to the presser bar 8 which is constantly urged downward by the spring 24, and the hook portion of the pull-up plate 22 has a function of the presser bar hanger 23 when the presser bar 8 is descending. Looking down in a non-contact state.

In the automatic presser lifting device configured as described above, when the sewing machine is in the upper stop position, that is, when the needle bar is in the upper stop position, the stopper arm 6 of the stopper arm 6 is rotated as the upper shaft 5 rotates. The arm portion 6a faces the direction opposite to the window plate 1 and is stopped. That is, the arm portion 6a of the stopper arm 6 is located outside the range of motion of the solenoid arm 3 having the stopper 4, and in this state, the motion of the solenoid arm 3 is not restricted at all. Therefore, when the plunger of the electromagnetic solenoid 2 is attracted, the solenoid arm 3 rotates clockwise by the stroke, and the solenoid link 13 is pulled to the right. Thereby, the pin 16 and the above-knee bar connecting rod 17 connected thereto are pulled, the pull-up link 19 is rotated clockwise, and the presser bar 8 and the cloth presser bar are pushed through the pull-up plate 22 and the presser bar hanger 23. 7 rises to the maximum against the force of the spring 24. As shown in FIG. 5, since the needle bar 25 and the needle bar thread hook 26 at this time are stopped at the upper position shown by the dotted line, the cloth presser 7 and the needle bar 25 and the needle bar thread hook 26 which are elevated to the dotted line position. Does not interfere with.

When the sewing machine stops downward, that is, when the needle bar is in the downward stop position, the arm portion 6a of the stopper arm 6 is rotated by the window plate as shown in FIG. 1 as the upper shaft 5 rotates. It has stopped in the direction of 1. That is, the arm portion 6a of the stopper arm 6 is located at a position where the stopper 4 collides when the solenoid arm 3 moves, whereby the movement of the solenoid arm 3 is restricted. Therefore, when the plunger of the electromagnetic solenoid 2 is attracted, the solenoid arm 3 rotates clockwise, but its movement is limited by the stopper 4 hitting the arm portion 6a of the stopper arm 6, and It will be forcibly stopped before rotating by the stroke of. Therefore, the amount of lifting of the presser bar 8 and the cloth presser 7 through the solenoid link 13, the knee-raising connecting rod 17, the pulling-up link 19, the lifting plate 22 and the like is smaller than that at the time of the upper stop. That is, as shown in FIG. 5, the work clamp 7 stops at the solid line position where it does not interfere with the needle bar 25 and the needle bar thread hook 26 which are stopped at the lower position shown by the dotted line.

Instead of adopting the stopper arm 6 as described above, another solenoid is provided which is activated by the signals of the upper and lower stop of the sewing machine, and when the solenoid stops downward, the electromagnetic A similar effect can be obtained by causing a stopper to appear on the locus of movement of the solenoid 2 or the solenoid arm 3 and withdrawing the stopper when the sewing machine stops above.

[0016]

[Effect of device]

 Since the present invention is configured as described above, it has the following effects.

That is, since the movement of the presser foot lifting solenoid is restricted when the sewing machine is stopped under the sewing machine, the cloth presser is placed at the upper stop position and the lower stop position of the needle bar so as not to interfere with the needle bar and the needle bar thread hook. It can be raised to the corresponding position. Therefore, the presser foot can be widened when the sewn product is taken in and out with respect to the presser foot of any shape or the sewing machine of the needle bar, and there is no problem even when the direction of the sewn product is changed. In addition, the amount of lifting of the work clamp when the machine is stopped under the sewing machine is smaller than that of the conventional one, so the time required for lifting and lowering it is shortened and the working time is shortened.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of an automatic presser lifting device according to the present invention.

FIG. 2 is a front view of the main part of the automatic presser lifting device of the present invention.

FIG. 3 is a front view of the vicinity of a presser bar of the automatic presser lifting device of the present invention (however, the direction of the presser foot is shown rotated by 90 °).

FIG. 4 is a perspective view showing a relationship between a presser foot lifting solenoid and a solenoid arm.

FIG. 5 is a side view of a sewing machine provided with the automatic presser lifting device of the present invention.

[Explanation of symbols]

 2 Solenoid for lifting the presser foot 3 Solenoid arm 4 Stopper 5 Upper shaft 6 Stopper arm 7 Cloth presser foot 8 Presser bar

Claims (1)

[Scope of utility model registration request] 1. An automatic presser foot lifting device provided with a stopper for restricting movement of a presser foot lifting solenoid when the bottom of the sewing machine is stopped in conjunction with rotation of the sewing machine.