JPS6140298Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to an air valve operating device for a sewing machine.

BACKGROUND OF THE INVENTION For example, an overlock sewing machine is provided with a clutch for transmitting and disconnecting the power of a motor disposed below a sewing machine table to a sewing machine pulley, and a clutch lever 1 for actuating this clutch, as shown in FIG.

One end of a first connecting rod 2 is rotatably supported on the clutch lever 1, and a mounting base 3 is attached to the first connecting rod 2 so as to be movable up and down.

The upper end of a second connecting rod 4 is further fixed to the mounting base 3, and the lower end of the second connecting rod 4 is supported by a starting pedal 5.

6 is an air valve fixed to the mounting base 3, and the push button 6A of the air valve 6 is normally connected to the air outlet 6a by a spring built into the valve 6.
The push button 6A is pushed down in a direction that blocks air from being ejected from the air outlet 6a, and the push button 6A is pushed up against the spring, thereby ejecting air from the air outlet 6a. Note that 6b is a supply port from an air supply source (not shown) to the air valve 6.

Reference numeral 7 denotes an actuating plate whose one end is screwed to the first connecting rod 2 and whose other end extends in a direction facing the push button 6A of the air valve 6.

Then, when the starting pedal 5 is depressed, the second connecting rod 4 is lowered, thereby lowering the mounting base 3 and the air valve 6. When the air valve 6 descends and the push button 6A comes into contact with the operating plate 7, the push button 6A moves upward against the spring and air is blown out from the air outlet 6a. It communicates with the air inlet and is used to remove empty rings.

Then, when the push button 6A is raised to its highest position and the air valve 6 is fully opened, the first connecting rod 2 begins to lower via the actuating plate 7 in conjunction with the lowering of the second connecting rod 4, thereby causing the clutch to close. When the lever 1 is lowered, the clutch which was in the cut-off state is engaged and transmits the rotational force of the sewing machine motor to the sewing machine pulley, thereby starting the sewing machine.

However, in the case of the air valve of such a sewing machine, the elastic force of the spring built into the air valve 6 is normally sufficient to prevent the air valve 6 from descending due to the weight of the second connecting rod 4 and the pedal, and air is not blown out. It has been strengthened. For this reason, if you want to reduce the feed speed of the sewing machine by leaving the clutch in a half-clutch state, the sewing machine will start before the air valve 6 is fully opened, which will weaken the suction force of the empty ring, resulting in the disadvantage that the empty ring cannot be fully discharged. Ta.

Purpose of the invention This invention was made in view of these drawbacks, and relates to an air valve for a sewing machine that operates satisfactorily even when the clutch is in a half-clutch state.

Embodiment Hereinafter, an embodiment of this invention will be described based on the drawings.

In Fig. 2, 10 is a sewing machine table, 11
12 is the sewing machine motor fixed to the bottom surface of the sewing machine table 10, and 12 is the sewing machine motor 10 and the clutch part 13.
14 is a clutch lever for disconnecting and connecting the clutch portion 13;
Normally, the spring 14S acts on the clutch portion 13 to interrupt the interlocking movement between the sewing machine motor 10 and the drive pulley 12.

15 is a first connecting rod whose upper end is supported by the clutch lever 14 and whose free end hangs downward; 16 is a fixed arm whose one end is fixed with a screw 17 and whose other end extends horizontally; and 18 is a first connecting rod at one end. This is a movable arm that engages two connecting rods 19 and has its other end rotatably supported by a fixed arm around a shaft P. 19A is a fixing member fixed to the upper end of the second connecting rod 19.

20 is a pedal supported on the second connecting rod 19; 21
is an air valve fixed to the middle part of the fixed arm 16, and the push button B is always in the upper position by a spring built into the air valve, and the air supplied from the air supply port 21b is ejected from the air jet port 21a. I am blocking it to prevent it from happening. When the push button B moves to the lower position against the spring, air is ejected from the air ejection port 21a.

Incidentally, reference numeral 22 denotes a press piece integrally formed on the movable arm 18 so as to face the push button B of the air valve 21.

Further, 23 is a holding base which is loosely fitted into the first connecting rod 15 and fixed to the second connecting rod 19.
5. The second connecting rod 19 is held in parallel.

Next, the operation of this invention will be explained.

When the pedal 20 is depressed, the second connecting rod 19 first moves downward, thereby also lowering the fixing member 19A. The lower part of the fixed member 19A contacts the right end of the movable arm 18, and the movable arm 18 rotates clockwise as a "lever" with the axis P as a fulcrum, and the press piece 22 of the movable arm 18 presses the push button of the air valve 21. In order to push B against the spring, air starts to be ejected from the air ejection port 21a. Then, when the push button B is pushed to the lowest position, the fixed arm 16 is now pressed by the movable arm 18 and begins to fall.

In conjunction with the lowering of the fixed arm 16, the first connecting rod 1
5 is lowered, whereby the clutch lever 14 is lowered, the clutch portion 13 is connected to the sewing machine motor 11, the drive pulley 12 is rotated, and the sewing machine is started.

In this way, the push button B of the air valve 21 is pressed by the "lever" action of the moving arm 18 with the shaft P as the fulcrum and the push piece 22 as the point of action, so the push button B is pressed with a stronger force than before. can do.

Note that the air valve 21 may be attached to the movable arm 18 side with the push button B facing downward.

As described above, according to this invention, since the air valve is actuated by the "lever" action of the movable arm, the acting force for pressing the air valve can be increased compared to the prior art. Therefore, even if the clutch is in the half-clutch state, the air outlet can be fully opened by overcoming the elastic force of the spring built into the air valve, and sufficient suction force can be obtained even when the sewing machine is started with the clutch in the half-clutch state. This has the effect that empty rings etc. can be completely removed.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional device, and FIG. 2 is a perspective view of an embodiment of the device. 15...First connecting rod, 16...Fixed arm, 18...
...Moving arm, 19...Second connecting rod, 20...Pedal, 21...Air valve.

Claims (1)

[Claims for Utility Model Registration] The first part supported on the clutch lever of the sewing machine motor
a connecting rod; a fixed arm having one end fixed to the first connecting rod; a movable arm having one end rotatably supported by the fixed arm and the other end engaging a second connecting rod; and a movable arm supported by the second connecting rod. An air valve is fixed to either the pedal, the movable arm, or the fixed arm, and is normally closed due to elastic force, and when the movable arm moves due to the operation of the pedal, the air valve opens against the elastic force. An air valve actuating device for a sewing machine, which is also characterized by the following features: