JPH105463A - Structure of needle falling adjusting device in zigzag sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate needle falling adjusting operation, and simplify a structure by arranging a long hole fitted to and installed in a small shaft on the other end of an amplitude rod whose one end is engaged with a zigzag generating device arranged in a sewing machine frame, and arranging an end surface coming into contact with a contact surface of an adjusting element. SOLUTION: An adjustable lock nut 14 of an adjusting element 11 can be moved on a contact surface of an end part only by directly rotating a screw 13 since the screw 13 is installed in an installing part 10 by being energized by a spring. Therefore, since a contact surface of the adjusting element 11 is always pressed against an end surface 12 of an amplitude rod 7 by spring pressure, a needle falling position supported by a needle bar support body 2 is finely adjusted in either left or right direction. Since the screw 13 is energized by the spring by the adjustable lock nut 14, the adjusting element 11 is fixed without fixing the screw 13 over again, and an optimal needle falling condition can be held only by simple screw operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a needle drop adjusting device for a zigzag sewing machine.

[0002]

2. Description of the Related Art The structure of a needle drop adjusting device in a conventional zigzag sewing machine is apparent from FIGS.
An eccentric pin 24 is attached to a connecting portion between a needle bar support 22 that swings and supports the needle bar 21 and an amplitude rod 23 that transmits an amplitude motion generated by a zigzag generating mechanism, and the eccentric pin is rotated as appropriate. The needle drop position is finely adjusted by the operation to optimize the thread loop capture state. However, the eccentric pin is fixed with the screw 25 so that the eccentric pin does not move during operation. However, when the eccentric pin is fixed with a screw, the needle drop is likely to be out of order in the above-described structure, so that the adjustment may need to be performed again, and the speed is lacking.

[0003]

SUMMARY OF THE INVENTION According to the present invention, a zigzag sewing machine transmits a needle bar support for supporting a needle bar so as to be able to swing laterally and slidably in a vertical direction, and an amplitude motion generated by a zigzag generator. An object of the present invention is to develop and provide a needle drop adjusting device in which the structure of the connecting portion to be connected to the amplitude rod is easy to adjust the needle drop and has a simple structure.

[0004]

SUMMARY OF THE INVENTION The present invention enables a small shaft provided on a swingable needle bar support pivotally attached to a part of a machine frame to be moved into an elongated hole provided at an end of an amplitude rod. The structure is such that the abutment surface of the adjustable adjustment element provided on the needle bar support is pressed against the end of the amplitude rod by a spring action so that the needle drop adjustment is easy and the structure is simple. The present invention provides a needle drop adjusting device for a zigzag sewing machine.

[0005]

According to the present invention, the needle bar is pivotally attached to a part of the frame of the sewing machine and is supported on the swingable needle bar support so as to be able to move up and down. The adjusting element is provided in the section, a zigzag generator provided inside the sewing machine frame is provided with a long hole to be fitted to the small shaft at the other end of the amplitude rod engaging one end, and a contact surface of the adjusting element is provided. By providing an end face which abuts on the zigzag sewing machine, the needle drop adjustment operation of the zigzag sewing machine can be performed accurately and easily, and the structure of the adjustment device can be simplified.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of one embodiment of the present invention will be described below with reference to FIGS.

A mechanism base 1 fixed to a part of a machine frame (not shown) of the zigzag sewing machine is pivotally pivotally mounted by a support shaft 3 fitted in a hole formed at an upper end of a needle bar support 2. Have been.

The needle bar support 2 is made of sheet metal, and holes are formed in the horizontal portions 4, 4 which are bent at right angles at appropriate two places, and are vertically penetrated on one axis. The needle bar 5 is fitted in the hole so as to be slidable in the axial direction.

A needle bar dowel 13 is fixed to an appropriate position on the needle bar, and a drive shaft supported by the sewing machine frame via the needle bar doki and other needle bar cranks (both not shown). The needle bar 5 is moved up and down by the rotation of a needle bar (not shown).

A small shaft 6 is provided at an appropriate position on a vertical portion of the side surface of the needle bar support 2, and a long hole 8 provided at an end of an amplitude rod 7 swings on the small shaft. The small shaft is fitted so that it can move in the direction, and the fitted state is maintained by the retaining ring 9 attached to the small shaft.

At an appropriate position of the needle bar support 2, there is provided a vertically bent adjusting element mounting portion 10, which is provided with a screw hole. An adjusting element 11 comprising an adjustable lock nut 14 is mounted.

The amplitude rod 7 is a member for transmitting a swinging motion generated by a zigzag generator provided in the sewing machine frame. One end is connected to a part of the zigzag generator and the other end is connected to the zigzag generator. The needle bar support 2 is connected to the needle bar support 2 via the elongated hole 8 and the small shaft 6 as described above, and is attached to the needle bar support 2 by the action of a spring (not shown) mounted on the needle bar support 2. The contact surface of the adjusting element 11 is pressed against an end surface 12 formed on the other end of the amplitude rod 7 so as to be parallel to the needle bar through hole of the needle bar support.

Accordingly, the zigzag motion generated by the zigzag generator in association with the rotation of the drive shaft is transmitted to the needle bar support 2 via the amplitude rod 7, and causes the needle bar 5 to continuously perform amplitude motion.

Since the embodiment of the present invention has the structure as described above, the needle bar 5 is moved up and down by rotating the drive shaft, and is oscillated in synchronization with the up and down movement. Can be

A sewing needle is attached to the lower end of the needle bar 5, and when the needle bar descends, it cooperates with a thread wheel catching device provided in a lower sewing machine frame and is passed through the sewing needle. A stitch can be formed by the upper thread and the lower thread in the thread catching device. However, a stitch cannot be formed unless the needle is properly dropped with respect to the thread catching device.

In such a situation, the position of the needle in the lateral (left and right) direction can be adjusted by operating the adjusting element 11 to move the needle to an appropriate position on the left and right.

That is, since the adjustable lock nut 14 of the adjusting element 11 is mounted on the mounting portion 10 by applying a spring bias to the screw 13, the end of the adjustable lock nut 14 is directly rotated only by directly turning the screw 13. Since the contact surface can be moved and the contact surface of the adjusting element 11 is always pressed against the end surface 12 of the amplitude rod 7 by spring pressure, the falling position of the needle supported by the needle bar support 2 is Fine adjustment is made in either the left or right direction, and the screw 13 is spring-biased by the adjustable lock nut 14, so the adjustment element 11 is fixed without fixing the screw 13 again, so it is optimal with only simple screw operation The needle drop state is maintained.

[0018]

Since the structure and operation of the embodiment of the present invention are as described above, an appropriate position of the needle bar support contacting an end surface formed at one end of the amplitude rod engaging one end with the zigzag generator. The needle drop position of the needle can be easily adjusted only by operating the screw of the adjustment element attached to the sewing machine, so that the assembly adjustment of the sewing machine can be performed in a short time, and the structure of the adjustment position is simple, so the production is easy. In particular, in the structure of the present invention, since the needle bar support can be made of sheet metal, it is easier to manufacture as compared with conventional die-cast or cast iron products and an assembly that can have a ripple effect that can reduce the weight. This is a great effect on work and production.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing a state where the present invention is mounted,

FIG. 2 is a side view of a main part showing a state where the present invention is mounted;

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a side view of a conventional embodiment.

FIG. 5 is a sectional view taken along line BB in FIG. 4;

[Explanation of symbols]

 2 Needle bar support 5 Needle bar 6 Small axis 7 Amplitude rod 8 Long hole 10 Mounting part 11 Adjustment element

Claims (1)

[Claims] A small shaft is provided on a side portion of the needle bar support that is swingably supported by a part of the sewing machine frame and supports the needle bar so that the needle bar can be moved up and down, and an adjusting element is attached to a mounting portion provided at an appropriate position,
It is preferable that a long hole to be fitted to the small shaft is provided at the other end of the amplitude rod that engages one end with the zigzag generator provided in the sewing machine frame, and that an end surface that comes into contact with the contact surface of the adjustment element is provided. Characteristic structure of needle drop adjustment device in zigzag sewing machine.