JPH0753901Y2 - Operating mode switching mechanism for driving machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Utilization of the Invention] The present invention relates to an operation mode switching mechanism of a pneumatic driven driving machine such as a nail driving machine.

[Background of the invention]

The driving machine has a continuous type in which the push lever can be operated to drive the stopper while the trigger is pulled, and the next stopper must be driven if the trigger is not released each time one stopper is driven. There is a one-shot type that can not be crowded.

In the continuous type driving machine, the machine body or the material to be driven may vibrate due to the recoil of driving, and the push lever may be operated, so that the fastener may be continuously driven. Therefore, it may be necessary to make a single shot even in the continuous type.

Further, in the single-shot type driving machine, it may be necessary to drive the stopper continuously.

For this reason, an operation mode switching mechanism capable of selecting continuous or single-shot driving according to the work is proposed by, for example, Japanese Utility Model Laid-Open No. 61-172783. This is because the base end of a plate-like engaging member that changes the bottom dead center position of the contact lever (trigger arm) pushed up by the push lever and the trigger is rotatably supported by the rotation shaft of the trigger, and the operation knob is The operation mode is switched by operating the tip of the engaging member to stand up or down.

However, because of such a configuration, two members of the rotation support shaft and the engagement member are required to raise or lower the plate-like engagement member, and a structure for connecting the rotation support shaft and the engagement member is required. There is a problem that it becomes complicated and assembly becomes difficult.

[Purpose of device]

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and provide an operation mode switching mechanism having a simple structure and easy to assemble.

[Outline of device]

According to the present invention, the rotary shaft of the operation mode switching lever is also used as the rotary shaft of the trigger, a part of the rotary shaft is cut out to form the eccentric cam portion, and the shaft end has a large diameter to form the operation knob portion. This is a switching lever in which the operation knob portion, the rotating shaft, and the eccentric cam portion are integrally formed. In addition, a steel ball that is pressed by the spring toward the machine body is built into the operation knob of the switching lever, and at least two recesses into which the steel ball is inserted are provided in the machine body so that the operation position of the switching lever can be fixed. It was done.

[Example of device]

 The present invention will be described below with reference to the accompanying drawings.

FIG. 4 is a partial sectional side view of the driving tool of the present invention. The driving tool 1 includes a piston 4 to which a striking rod 2 is integrally connected, which reciprocally slides in a cylinder 3, a cylinder valve 5 that opens and closes an upper surface of the cylinder 3 to operate the piston 4, and a cylinder via an air passage 13. Cylinder valve 5 that communicates with the upper surface of valve 5
The trigger valve 6, the push lever 7 and the trigger 8 for operating the trigger valve 6, the return air chamber 14 for returning the piston 4, and the cylinder 3 for supplying compressed air into the return air chamber 14. It is composed of a hole 15 and the like provided in the.

FIG. 1 is a side sectional view of the trigger valve 6 when the push lever 7 and the trigger 8 are operated. The plunger 10 is pushed up by the trigger arm 9 to shut off the accumulator chamber 11,
The cylinder valve 5 communicates with the atmosphere. At this time, the cylinder valve 5 is opened and the piston 4 is in a lowered state.

2 shows the trigger valve 6 when only the push lever 7 is returned after the switching lever 12 is in the continuous position and is operated as shown in FIG. 1 to lower the piston 4 to strike the stopper.
Indicates. At this time, since the switching lever 12 is in the continuous position, the plunger 10 returns, shuts off the atmosphere, and the cylinder valve 5 and the pressure accumulating chamber 11 communicate with each other. At this time, the cylinder valve 5 is closed and the piston 4 is in a state of returning.

3 shows that when the switching lever 12 is in the single-shot position, it is operated as shown in FIG. 1 to lower the piston 4 and hit the stopper,
The trigger valve 6 when only the push lever 7 is returned is shown. At this time, since the switching lever 12 is in the single-shot position, the trigger arm 9 and the plunger 10 are not completely returned, and the cylinder valve 5, the atmosphere and the pressure accumulating chamber 11 are shut off. At this time, the cylinder valve 5 remains open and the piston 4 is in the lowered state.

FIG. 5 shows a part of the rotary shaft 16 of the trigger 8 inside the trigger 8 which is cut away to form an eccentric cam portion, and the shaft end protruding to the eighth floor of the trigger is formed as a large-diameter operation knob portion to form a switching lever 12. It is sectional drawing which shows what was said. A spring 17 and a steel ball 18 pressed by the spring 17 toward the machine body 19 are built in the operation knob portion of the switching lever 12, and the steel ball 18 enters at least two recesses provided in the machine body 19 and switches. The lever 12 is fixed in its operating position.

One impact cycle will be described with reference to FIGS. 1 to 4. By operating the push lever 7 and the trigger 8 in the driving machine 1, the plunger 10 is pushed up via the trigger arm 9 in the trigger 8. As a result, the air passage
Compressed air on the upper surface of the cylinder valve 5 communicating with the trigger valve 6 via 13 is discharged to open the cylinder valve 5. Therefore, the compressed air in the pressure accumulating chamber 11 flows into the cylinder 3, and the piston 4 descends to strike the stopper.

Compressed air is also accumulated in the return air chamber 14 via the hole 15.

When the switching lever 12 is in the continuous position shown in FIG. 2, the plunger 10 returns even if the trigger 8 for returning the push lever 7 is pulled, and the compressed air in the pressure accumulating chamber 11 flows into the upper surface of the cylinder valve 5 and the cylinder valve 5 And the piston 4 returns by the compressed air accumulated in the return air chamber 14.

When the switching lever 12 is in the single-shot position shown in FIG. 3, the trigger 8
When pulling, the plunger 10 is returned only part way by the trigger arm 9 even if the push lever 7 is returned, and the piston 4 is maintained in the lowered state. When the trigger 8 is released, the plunger 10 returns and the piston 4 returns.

[Effect of device]

As described above, according to the present invention, the rotary shaft, the eccentric cam part, and the operating part are formed by notching a part of the trigger rotary shaft to form the eccentric cam part and forming the operation knob part with a large diameter at the shaft end. It is possible to provide an operation mode switching lever in which the knob portion is integrally formed, and it is possible to provide an operation mode switching mechanism having a simple configuration and easy assembly. Also, since the switch lever can be fixed in its operating position, there is no risk of the switch lever moving due to vibrations during driving, etc.
The switching operation can be reliably performed, and the operational effects such as improved safety can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention. FIGS. 1 to 3 are sectional side views showing the periphery of a trigger valve which constitutes an operation mode switching mechanism of the present invention, and FIG. FIG. 5 is a partial cross-sectional side view showing an essential part of the driving tool of the present invention, and FIG. 5 is a cross-sectional view showing the periphery of the switching lever. In the figure, 1 is a driving tool, 2 is a striking rod, 3 is a cylinder,
4 is a piston, 5 is a cylinder valve, 6 is a trigger valve, 7 is a push lever, 8 is a trigger, 9 is a trigger arm, 10 is a plunger, 11 is a pressure accumulating chamber, 12 is a switching lever, 13
Is an air passage, 14 is a return air chamber, 15 is a hole, 16 is an eccentric cam,
17 is a spring, 18 is a steel ball, and 19 is an airframe.

Claims (2)

[Scope of utility model registration request] Claim: What is claimed is: 1. A piston, which is integrally connected to a striking rod that strikes a fastener such as a nail, and is slidably accommodated in a cylinder, a cylinder valve that connects a pressure accumulating chamber in the body to the inside of the cylinder, and the cylinder. A trigger valve having a plunger that opens and closes between the valve and the atmosphere or between the cylinder valve and the accumulator, a push lever whose lower end is movable up and down around the injection port where the stopper is driven, and a trigger valve provided near the trigger valve. , A trigger operated by an operator, a trigger arm provided in the trigger and pushed up when the trigger and the push lever are operated to push up the plunger, and a trigger arm provided near the free end of the trigger arm to rotate the trigger. A driving machine having a trigger rotation shaft movably supported, wherein a part of the trigger rotation shaft located inside the trigger is partially cut away An eccentric cam portion that changes the bottom dead center position of the trigger arm is formed, an operation knob portion is formed with a shaft end protruding outside the trigger having a large diameter, and the trigger rotation shaft is an operation mode switching lever. Operating mode switching mechanism for embedded machines. 2. A steel ball which is pressed against the machine body by a spring is built in a portion of the operation knob portion of the trigger rotary shaft facing the machine body, and a recess portion into which at least two steel balls are inserted is provided in the machine body. 2. An operating mode switching mechanism for a driving machine according to claim 1, wherein the switching lever is fixed to its operating position by the recess and the steel ball.