JP2659443B2 - Middle presser drive for sewing machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a middle press driving device of a sewing machine, and more particularly to a middle press driving device of a sewing machine capable of adjusting a height of a middle press with respect to a needle plate.

[Conventional technology]

Conventionally, as this kind of intermediate presser driving device, the one shown in FIG. 3 is known. In the intermediate presser driving device, when the upper shaft 1 rotates, this rotation is transmitted to the needle bar 6 as a vertical movement via the counterweight 2, the crank rod 3, the connecting shaft 4, and the needle bar holder 5, and the needle bar 6 is moved. It is guided by the needle bar upper metal 8 and the needle bar lower metal 9 fixed to the machine frame 7, and moves up and down together with the needle 10 attached to the lower end thereof.

An eccentric cam 11 provided on the upper shaft 1 causes the eccentric cam holder 12, the shaft 13, and the oscillating lever 14 to rotate the rotating shaft 15, and the oscillating lever connected to the tip of the rotating shaft 15. 16 is rocking.

Further, the long hole at the tip end of the swing lever 16 is swingably loosely fitted to a shaft 18 fixed to the vertical shaft 17, and the vertical shaft 17 is connected to the middle presser bar upper metal 19 fixed to the machine frame 7. It is guided by the presser bar lower metal 20, and moves up and down together with the middle presser piece 21 attached to the lower end thereof.

[Problems to be solved by the invention]

In such a conventional intermediate presser driving device, the intermediate presser
The structure for moving the 21 up and down is complicated, the mass becomes large, and there are drawbacks such as the large number of swinging parts and the large vibration of the sewing machine.

In the case of the conventional intermediate presser driving device, when the thickness of the cloth changes or when sewing a cloth having a step portion, the intermediate presser
It is necessary to change the mounting position of 21.Each time, it is necessary to adjust the mounting position of the intermediate presser piece 21 by stopping the sewing machine and loosening the screw 22 that fixes the intermediate presser piece 21 to the vertical shaft 17. It was troublesome.

 The present invention has been made to eliminate the above disadvantages.

[Means for solving the problem]

An intermediate presser driving device for a sewing machine according to the present invention comprises an eccentric cam for moving a horizontal shaft rotated by an upper shaft, a first sprocket connected to the horizontal shaft, and an upper and lower shaft connected to the intermediate presser to a needle plate up and down. A second sprocket connected to the shaft of the eccentric cam, a timing belt suspended between the first and second sprockets, and a mechanism for vertically moving the second sprocket relative to the needle plate. It is characterized by comprising.

(Operation)

In the center press driving device of the sewing machine of the present invention, the center press piece is moved up and down via the timing belt and the eccentric cam by the rotation of the upper shaft, and the middle press piece is moved relative to the needle plate together with the vertical shaft by turning the adjustment knob. It can be moved up and down.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the present invention, as shown in FIG.
The horizontal axis 25 which makes the rotation of 1 perpendicular to 1 on the upper axis via gears 23 and 24
And the first sprocket is attached to one end of the horizontal shaft 25.
While fixing 26, the cam receiver 27 is fixed to the vertical shaft 17,
The cam shaft 29 of the eccentric cam 28 engaged with the cam receiver 27
Is fixed, and the timing belt 31 is suspended on the first and second sprockets 26, 30.

An upper and lower fixing portion 33 is provided at a substantially intermediate portion of a sprocket mounting plate 32 which rotatably supports the horizontal shaft 25 and the cam shaft 29 at both ends thereof, and a screw mounting plate 34 is provided on the machine frame 7. The lower part of the upper and lower screw 35 which is rotatably supported through is screwed into the upper and lower fixing part 33, and the upper part of the upper and lower screw 35 is provided with an adjusting knob 36.
To fix.

Further, a handle 38 is connected to the other end of the horizontal shaft 25 via a one-way clutch 37.

Since the intermediate press drive device of the present invention has the above-described configuration, the rotation of the upper shaft 1 is performed by the gears 23 and 24, the horizontal shaft 25, the first sprocket 26, the timing belt 31, the second sprocket 30, and the cam. The power is transmitted to the eccentric cam 28 via the shaft 29, whereby the vertical shaft 17 is moved up and down via the cam receiver 27.

In the intermediate presser drive device of the present invention, when it is desired to move the sewing machine by hand, if the sewing machine is stopped and the handle 38 is rotated, the vertical shaft 17 can be moved up and down. In the case of changing the thickness, for example, by turning the adjustment knob 36, the sprocket mounting plate 32 moves up and down about the horizontal shaft 25 via the upper and lower screws 35 and the upper and lower fixing portions 33, and the second sprocket 3
The intermediate presser 21 moves up and down relative to a needle plate (not shown) together with the vertical shaft 17 via the camshaft 29, the eccentric cam 28, and the cam receiver 27 without changing the rotational phase of the eccentric cam 28. The vertical position of the middle presser piece 21 with respect to the needle plate can be adjusted.

Incidentally, in the intermediate presser driving device of the present invention, a pulse motor 39 is used as the adjustment knob 36 as shown in FIG.
If the pulse motor 39 is driven according to a program, the position of the middle presser piece 21 can be automatically controlled.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to the intermediate press drive device of the present invention, as described above, there are few swinging parts, so that there is little vibration, and there is a great advantage that the initial position and the vertical position of the intermediate press piece can be easily adjusted. .

[Brief description of the drawings]

FIG. 1 is a perspective view of an intermediate press drive device of the sewing machine of the present invention, FIG. 2 is a perspective view of a main part in another embodiment of the present invention, and FIG.
FIG. 1 is a perspective view of a conventional intermediate press driving device of a sewing machine. 1 ... upper shaft, 2 ... counterweight, 3 ... crank rod, 4
... Connecting shaft, 5 ... Needle bar holding, 6 ... Needle bar, 7 ... Machine frame, 8 ... Needle bar upper metal, 9 ... Needle bar lower metal, 10 ...
Needle, 11 eccentric cam, 12 eccentric cam holder, 13 shaft
14… swing lever, 15… rotating shaft, 16… swing lever,
17… vertical axis, 18… axis, 19… metal on middle presser bar, 20
…… Metal presser bar lower metal, 21 …… Medium presser piece, 23,24 …… Gear, 25 …… Horizontal axis, 26 …… First sprocket, 27 …… Cam receiver, 28 …… Eccentric cam, 29… ... Cam shaft, 30 ... Second sprocket, 31 ... Timing belt, 32 ... Sprocket mounting plate, 33 ... Vertical fixing part, 34 ... Screw mounting plate,
35: Vertical screw, 36: Adjustment knob, 37: One-way clutch, 38: Handle, 39: Pulse motor.

Claims (4)

(57) [Claims] An eccentric cam for moving a horizontal shaft rotated by an upper shaft, a first sprocket connected to the horizontal shaft, an upper and lower shaft connected to an intermediate presser up and down with respect to a needle plate, and an eccentric cam. A second sprocket connected to a cam shaft; a timing belt suspended between the first and second sprockets; and a mechanism for vertically moving the second sprocket relative to a needle plate. Presser drive for the sewing machine. 2. The intermediate presser driving device according to claim 1, further comprising a manual rotating mechanism connected to the horizontal axis via a one-way clutch. 3. The intermediate press drive device according to claim 1, wherein the vertical movement mechanism of the second sprocket is an adjustment knob that is manually operated. 4. The intermediate presser driving device according to claim 1, wherein the vertical movement mechanism of the second sprocket is a pulse motor driven in accordance with a program.