JPS6215028Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a knee operating device for a sewing machine.

BACKGROUND ART Conventionally, in sewing machines, knee operating devices have been used for various purposes such as raising and lowering the presser foot, changing the feed amount during sewing, and changing the needle stop position.

Generally, as shown in FIG. 4, the knee operating device has a support leg b protruding from the lower surface of an oil pan a attached to a sewing machine table.
A support shaft c is rotatably supported around a horizontal axis, and a rod e is attached to this support shaft c via a mounting body d.
was fixed, and a knee rest g was fixed to this rod e via a mounting body f.

Therefore, when the knee rest g is operated by the worker's knee, the central part of the knee rest g moves along the locus A-A, which is a circular arc centered on the support axis c; The worker's knee part, which is opposite to the center part of the knee pad g, follows an approximate trajectory B- with the foot as the center.
It moves along a large circular arc as shown by line B. Therefore, when the knee pad g is operated, there is a difference of distance h between the two trajectories, and a relative movement occurs between the worker's knee and the knee pad g by the amount of the difference, and the worker's knee This resulted in defects such as causing discomfort to workers, causing damage to workers' pants and knee pads due to continuous work over a long period of time, and even causing scratches to workers' own knees. .

Purpose Therefore, in the present invention, when the worker operates the knee pad, the difference between the trajectory of the knee part of the worker and the trajectory of the knee pad facing the knee part is small, so that the above-mentioned inconvenience occurs. The purpose of this invention is to provide a knee operating device for a sewing machine that does not have a conventional sewing machine.

Solution In order to achieve the above purpose, in this invention,
A pair of links are provided on the sewing machine table, the upper ends of which are rotatably supported around axes that are spaced apart from each other and parallel to each other, and the lower ends of the pair of links are each rotatable. Connecting links are provided, the distances between mutually opposing rotation supports of the four-joint rotation mechanism constituted by these links are set to be approximately equal, and furthermore, knee pads are attached to the connecting links or the members fixed thereto. .

Embodiment An embodiment embodying the present invention will be described with reference to the drawings.

An oil pan 1 is attached to a sewing machine table (not shown), and a sewing machine head (not shown) is placed on the oil pan 1.

A presser foot 2 is supported on the frame of the sewing machine head so as to be movable up and down, a presser foot holder 3 is fixed to the intermediate portion, and a cloth presser foot 4 is attached to the lower end. A downward pressing force is applied to the presser bar 2 by a cloth presser spring 6 located between the presser bar holder 3 and a presser foot pressure adjustment screw 5 screwed into the frame. Reference numeral 7 designates a first bell crank lever whose intermediate portion is rotatably supported by the frame, one arm 7a facing below the presser bar holder 3, and the other arm 7b extending from the second bell crank lever via a connecting rod 8. The bell crank lever 9 is connected to one arm 9a of the bell crank lever 9. The middle portion of the second bell crank lever 9 is also rotatably supported by the frame, and the upper end of the knee raiser bar 10 is connected to the other arm 9b. Further, reference numeral 11 denotes a push rod supported by the oil pan 1 so as to be movable up and down, and the enlarged diameter portion at the upper end faces the lower end of the knee raiser rod 10.

The operating shaft 12 is rotatably supported by a support leg 1a protruding from the oil pan 1 about a horizontal axis. The operating shaft 12 has an intermediate portion of an operating lever 14 fixed to one end by a set screw 13, and a first swing link 15 attached to the other end by a set screw 13.
It is fixed by 6.

One arm of the operating lever 14 extends to face the lower end of the push rod 11, and moves the push rod 11 upward when the operating shaft 12 is rotated counterclockwise in FIG. In addition, the operating lever 14
Each arm has a stopper screw 17,
18 is screwed in so as to be adjustable up and down, and engages with the lower surface of the oil pan 1 to set the clockwise and counterclockwise rotation amounts of the operating lever 14 and the operating shaft 12 to appropriate amounts.

A coil spring 19 is wound around the operating shaft 12 and is locked between the operating lever 14 and the lower surface of the oil pan 1.
2 in the counterclockwise direction in FIG. 1, and the knee rest, which will be described later, is placed in an inactive position.

The support shaft 20 is rotatably supported by a support leg 1b protruding from the oil pan 1 so that it is parallel to and at the same height as the operating shaft 12.

A second swing link 21 is fixed to one end of the support shaft 20 facing the first swing link 15 with a set screw 22 .

The first and second swing links 15 and 21 have exactly the same structure, and each includes U-shaped frames 23 and 24, boss portions 25 and 26 fixed to their upper ends, and frames 23 and 24, respectively. It is composed of two prongs 27 and 28 formed by cutting out a part of the lower ends of 23 and 24.

The first and second swing links are fixed to the operating shaft 12 and the support shaft 20 at the boss portions 25 and 26, respectively, by the set screws 13 and 22 as described above. In addition, a pair of small holes are formed through each of the two prongs 27 and 28, and the first and second swing links 15 and 21 are rotatably connected and a four-bar rotation mechanism is provided. A connecting link 31 for configuring the pin 3 is fitted and supported in the pair of small holes and is prevented from moving in the axial direction.
2,33.

The distance between the axes of the pins 32 and 33 that rotatably support the connecting link 31 is set equal to the distance between the axes of the operating shaft 12 and the support shaft 20. Regardless of the rotation of the first and second swing links 15 and 21, the connecting link 31 is always supported horizontally.

The connecting link 31 has an inverted T-shape in the center with a support arm 31a that protrudes forward and upward, and an arm 34a extending in the left-right direction of a rod 34 bent into an L-shape is slidably inserted into the upper end of the support arm 31a and fixed in place by a set screw 35.

The movable body 36 includes a support part 36a that is fitted into the arm part 34b of the rod 34 that extends in the vertical direction so as to be movable in the vertical direction and rotational direction, and a vertical knee that is made of a soft material such as sponge or rubber. A disc-shaped portion 36b covered by a knee pad 37 having a contact surface 37a is movably inserted into the arm portion 34b of the rod 34 and fixed by a set screw 38. The vertical position of the movable body 36 is determined by the hooking body 39 .

In the above-mentioned embodiment, since it has the above-mentioned configuration, the knee pad 37 is now placed on the worker's knee.
When is operated to the right, the connecting link 31 is moved to the right while remaining horizontal, and the first swing link 15 is moved to the right while remaining parallel to the second swing link 21, and the coil spring 19 is moved to the right. The actuating shaft 12 resists the action of
At the same time, the actuating lever 14 is rotated counterclockwise in FIGS. 1 and 2, and the push rod 1 is rotated.
1. The knee raiser bar 10 is pushed up, and the first bell crank lever 7 is rotated clockwise in FIG. 1 via the second bell crank lever 9 and the connecting rod 8.
The presser bar 2 and the presser foot 3 are raised against the action of the presser spring 6.

At this time, the knee pad 37 moves along the locus C--C while the knee pad surface 37a is kept vertical, as shown in FIG. Incidentally, the arc B-B line in the figure is the locus when the worker's knee moves centering on the foot, and within the operation range of the knee pad 37, the arc B-B line and C
-The difference from line C is slight.

Effects In the present invention, a pair of links are rotatably supported around an axis parallel to each other at a distance from a mounting member fixed to the sewing machine table, and a connecting link rotatably connects the lower ends of the links. and
The distances between the mutually opposing rotation supports of the four-joint rotation mechanism constituted by these are set approximately equal, and knee pads are attached to the connecting link or the member fixed thereto, so that the worker's knee is centered around the foot. There is almost no difference between the trajectory of the knee pad and the trajectory of the knee pad, and the knee pad is always held at a constant angle, so the operator does not feel uncomfortable when operating the knee pad. No inconvenience will occur even if the work is performed continuously for a long time without giving any stress.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is an overall mechanical diagram, FIG. 2 is a front view showing the main parts, and FIG. 3 is a D--D in FIG. It is a sectional view taken along the D line. Further, FIG. 4 is an explanatory diagram showing the prior art. In the figure, 1 is an oil pan, 1a and 1b are support legs constituting a mounting body, 12 is an operating shaft, 15 and 2
1 is a first and second swing link constituting a pair of links, 31 is a connecting link, 34 is a rod, 37
is a knee pad.

Claims (1)

[Scope of claim for utility model registration] Mounting body 1a, 1 fixed to sewing machine table
axes 12, 20 spaced apart and parallel to b;
A pair of links 15, 21 whose upper ends are rotatably supported around the pair of links 15, 21, and a connecting link 31 which is rotatably connected to the lower ends of the pair of links 15, 21, forming a four-bar rotation mechanism. The distances between mutually opposing rotation supports of the four-joint rotation mechanism are set to be approximately equal; The knee rest 37 is attached to the connecting link 31 or a member 34 fixed thereto; The four-joint rotation mechanism A knee operating device for a sewing machine, characterized in that it is provided with a motion transmitting means (12, etc.) operatively connected to one element constituting the sewing machine, and operating at least one of various mechanisms of the sewing machine.