JPH05138548A - Automatic repeating device for driving machine - Google Patents

Abstract

PURPOSE:To increase the driving speed and the driving force of a stopping piece of a driving machine by utilizing the effect that the compressed air do not flow into a main valve chamber when a main valve is moving backward and the action of the main valve becomes rapid. CONSTITUTION:When a trigger is drawn in driving a stopping piece 27, a stem 48 moves backward, and a valve part communicates the first pilot air chamber with the atmosphere. A pilot valve 47 is moved forward by the air pressure exerted on the third piston part 56, and communicates a main valve chamber 41 with the atmosphere to open a main valve 35. The compressed air flows into a cylinder 21a to move a piston 23 forward, and a driver 22 drives the stopping piece 27. Then, the compressed air forward of the piston flows into a returning air chamber 29, pushes a piston part 54 from inside the second pilot air chamber 50 to move the pilot valve backward, and the compressed air is sent to the main valve chamber. The main valve closes the cylinder and discharges the compressed air from the rear end part of the cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic repeater for a driving machine.

[0002]

2. Description of the Related Art An automatic repeater for a driving machine disclosed in Japanese Patent Laid-Open No. 2-172682 has a structure as shown in FIG. In the device, the forward movement of the main valve 1 during the repeated driving operation guides the compressed air in the air chamber 5 to the main valve chamber 4 through the passage 2 provided in the housing and the passage 3 provided in the main valve 1. Done by.
As a result, the introduction of compressed air into the cylinder 6 is cut off. The rearward movement of the main valve 1 is performed by pulling the trigger 7 to release the compressed air in the main valve chamber 4 from the passage 8 into the atmosphere and reduce the pressure. As a result, compressed air is introduced into the cylinder 6, and the piston advances and drives.

The device structure disclosed in Japanese Patent Publication No. 58-50833 is as shown in FIG. In this device, when the trigger 9 is pulled, the trigger valve stem 10 retracts, the O-ring 11 comes into close contact with the front end surface of the pilot valve stem 12, and when the trigger 9 is further pulled and operated, the O-ring 13 moves from the intermediate step portion. Located remotely in the pilot air chamber. As a result, the working air in the pilot air chamber is discharged into the atmosphere through the gap between the stem and the opening, and the pilot valve stem 12
The pressure of the working air acting on the front end face of the pilot valve stem 12 disappears, the pressure of the working air acting on the rear end face of the pilot valve stem 12 becomes relatively large, and the pilot valve stem 12 moves forward by this pressure. As a result, the communication hole 14
And the exhaust passage 15 are connected by the small diameter portion of the pilot valve stem 12, the operating air in the air passage 16 and the main valve chamber is discharged into the atmosphere through the communication hole 14 and the exhaust passage 15, and the main valve acts on the front end face. It moves backward by operating air pressure from the main air chamber 17. As a result, working air flows into the main cylinder and advances the piston.

[0004]

However, the above-described conventional automatic repeater for a driving machine is disclosed in the former Japanese Patent Laid-Open No. 2-172.
In the 682 publication, the compressed air in the air chamber 5 continues to flow into the main valve chamber 4 through the passages 2 and 3 even when the main valve 4 is retracted. For this reason, the decompression speed of the main valve chamber 4 is slowed down, the retreat speed of the main valve 1 is slowed down, and an instantaneous large amount of compressed air in the air chamber 5 is prevented from flowing into the piston upper chamber 18. In addition, since the pressure of the compressed air in the air chamber 5 is also reduced, the driving force is reduced.

Further, since the passages 2 and 3 cannot be made too large for the above reason, the inflow of compressed air into the main valve chamber 4 is restricted even when the main valve 1 moves forward, and the forward speed of the main valve 1 slows down. There is. Therefore, it has a drawback that the main valve 1 moves back and forth slowly and the repetitive driving speed is slow. Moreover, since the repetitive valve 19 is provided independently, the structure is complicated.

The latter Japanese Patent Publication No. 58-50833 has a drawback that only a single shot is possible and continuous shots are not possible. The present invention aims to solve such problems.

[0007]

To achieve the above object, the present invention selects a cylinder accommodating a piston for holding a driver, and a rear end portion of the cylinder to either the atmosphere or the compressed air supply chamber side. Driven with a main valve for electrically reciprocally moving the piston to reciprocate, and a trigger valve for switching supply and discharge of compressed air for opening and closing the main valve to and from a main valve chamber for operating the main valve In the automatic repeater of a machine, the trigger valve is the same as the trigger valve cylinder having a through hole communicating from the trigger side to the compressed air supply chamber side, and the through hole slidably inserted in the trigger valve cylinder. A pilot valve having a directional through hole, and inserted across the through hole of the trigger valve cylinder and the through hole of the pilot valve,
The front part has a stem protruding toward the trigger, and the trigger valve cylinder is connected to the first pilot air chamber and the return air chamber of the cylinder from the front part to the rear part in the through hole. A second pilot air chamber, a communication hole to the atmosphere, and a communication hole connected to the main valve chamber are sequentially formed, and the pilot valve corresponds to the first pilot air chamber from its front part to its rear part. The first piston portion, the second piston portion corresponding to the second pilot air chamber, and the pilot hole when the pilot valve advances, the communication hole is conducted to the conduction hole through the communication hole of the trigger valve cylinder, and compressed when retracted. A valve portion that is electrically connected to the air supply chamber and a third piston portion that has a smaller diameter than the first piston portion that is exposed to the compressed air supply chamber side are sequentially formed. , The first pilot air chamber is connected to the compressed air supply chamber through the through hole of the pilot valve when the stem moves forward to the trigger side, and the first pilot air chamber moves when the backward movement is caused by the trigger pulling. A structure is provided in which a valve portion is provided which is electrically connected to the atmosphere through the through hole of the trigger valve cylinder.

[0008]

First, when the trigger is not pulled yet, the stem is in the forward position and the valve portion of the stem shuts off the connection between the first pilot air chamber and the atmosphere. Compressed air enters the first pilot air chamber through the through hole of the pilot valve. Since the first piston portion has a larger diameter than the third piston portion, the pilot valve retracts. Therefore, the valve portion of the pilot valve connects the communication hole to the compressed air supply chamber, the compressed air enters the main valve chamber and presses the main valve 5 against the cylinder end, and shuts off between the compressed air chamber and the cylinder ( (Fig. 1).

When the trigger is pulled when driving a nail or the like, the stem retracts, and the valve portion of the stem causes the inside of the first pilot air chamber to communicate with the atmosphere through the through hole of the trigger valve cylinder. Therefore, the compressed air in the first pilot air chamber flows out into the atmosphere, and the pilot valve advances due to the compressed air pressure applied to the third piston portion. As the pilot valve moves forward, its valve portion brings the communication hole into conduction through the through hole of the trigger valve cylinder. Therefore, the compressed air in the main valve chamber flows into the atmosphere through the communication hole and the communication hole, and the main valve opens the cylinder. Compressed air flows into the cylinder and drives the piston. The piston moves forward with the driver, and the driver drives out a nail or the like (FIGS. 3 and 5).

As the piston advances, the compressed air in front of the piston flows into the return air chamber. The air pressure acts on the second piston portion of the pilot valve from within the second pilot air chamber of the trigger valve. Therefore, the pilot valve retracts, and the communication hole is connected to the compressed air supply chamber. The compressed air flows into the main valve chamber through the communication hole and moves the main valve to the cylinder side (Fig. 7). The movement of the main valve causes the rear end of the cylinder to communicate with the atmosphere, and the compressed air is discharged from the rear end of the cylinder (FIG. 9). Therefore, the piston returns to the rear by the compressed air in front of it.

With the return of the piston, the compressed air in front of the piston expands, the pressure decreases, and the compressed air flows out through the gap on the driver side into the atmosphere. Therefore, the pressure in the second pilot air chamber also drops, and the pilot valve advances due to the pressure of the compressed air applied to the third piston portion thereof. Then, the same operation as described above is repeated, and the stopper is driven into the driven material.

When the trigger is released, the stem moves forward and returns with the compressed air pressure introduced through the through hole of the pilot valve. The valve portion switches the first pilot air chamber from the atmosphere to the compressed air chamber side as the stem moves back. Therefore, compressed air flows into the first pilot air chamber, and the pilot valve is retracted. Therefore, compressed air enters the main valve chamber and the main valve closes the rear end of the cylinder to stop the repetition of the driving operation.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of an automatic repeater for a driving machine according to the present invention will be described below with reference to the drawings.

As shown in FIG. 11, this driving machine is
It has a hollow housing 20 as its main body.
A cylinder 21 is housed in the housing 20, and a piston 23 holding a driving driver 22 is housed in the cylinder 21 so as to be movable back and forth.

A guide cylinder 25 which serves as a passage for the driver 22 is connected to a front end plate 24 which closes the front end of the housing 20. The stopper supply unit 2 is provided in the middle of the guide tube 25.
6 is connected, and the guide cylinder 25 also serves as a passage for guiding the stopper 27 sent from the stopper supply portion 26.

An empty space is provided between the housing 20 and the cylinder 21, and the empty space is divided into front and rear by a partition wall 28. The front room is used as a return air room 29, and the rear room is a compressed air supply chamber 3 for supplying compressed air.
It is 0. The return air chamber 29 communicates with the inside of the cylinder 21 via a rear ventilation hole 31 and a front ventilation hole 32 that penetrate the cylinder wall at the rear and front portions. A check valve 33 that prevents the backflow of air into the cylinder 21 is provided in the rear vent hole 31. The compressed air supply chamber 30 extends into the handle portion 34 provided on the lower side of the housing 20, and the compressed air is supplied from this vacant chamber.

The rear end of the housing 20 and the cylinder 21
A main valve 35 for selectively reciprocating the interior of the rear portion of the cylinder 21 between the compressed air supply chamber 30 and the atmosphere to reciprocate the piston 23 is interposed between the rear end and the rear end. On the other hand, at the rear end of the housing 20, tubular guides 36a and 36b for guiding the reciprocating motion of the main valve 35 and the main valve 35 are provided.
And a compression coil spring 37 for urging the valve toward the cylinder 21 side.

The main valve 35 has a large diameter portion 35a and a small diameter portion 35.
and a seal 38 is attached to the front edge of the large diameter portion 35a to open and close the valve seat at the rear edge of the cylinder 21, and the rear portion of the small diameter portion 35b. Is a valve portion 40 that seals the inside of the cylinder 21 or connects to the atmosphere by contacting with and separating from the valve seat 39 attached to the housing 20 side.

The guides 36a and 36b are provided with a large diameter portion 36a and a small diameter portion 36b corresponding to the large diameter portion 35a and the small diameter portion 35b of the main valve 35, respectively.
Between the large diameter portion 35a and the small diameter portion 35b of the main valve chamber 41
Is formed.

A trigger 42 and a trigger valve 43 for switching the supply and discharge of the main valve opening / closing compressed air to / from the main valve chamber 41 are provided near the base of the handle portion 34 of the housing 20. ..

Main valve chamber 41 and compressed air supply chamber 30
An air passage 44 is connected to the air passage 44, and the air passage 44 is selectively connected to the inside of the compressed air supply chamber 30 or the atmosphere by operating the trigger valve 43.

That is, the trigger valve 43 is arranged in the ventilation passage 4
4 operates in the atmosphere, the inside of the main valve chamber 41 becomes the same as the atmospheric pressure, and the main valve 35 resists the compression coil spring 37 by the compressed air in the compressed air supply chamber 30 applied to the front edge thereof. And then separated from the cylinder 21. As a result, the main valve 35 opens the cylinder 21 and shuts off the inside of the cylinder 21 from the atmosphere, and the piston 23 inside the cylinder 21 receives the supply of compressed air and moves from the rear to the front.

On the contrary, when the trigger valve 43 operates so that the ventilation passage 44 is connected to the compressed air supply chamber 30 side, the compressed air flows into the main valve chamber 41 and the compression coil spring 37 and the main valve 35 are connected to the cylinder 21 side. Move to. As a result, the main valve 35 closes the cylinder 21 and connects the inside of the cylinder 21 to the atmosphere. As a result of the supply of compressed air being cut off, the piston 23 in the cylinder 21 returns from the front to the rear by the force of the compressed air in the return air chamber 29.

As shown in FIGS. 1 to 10, the trigger valve 43 is provided with the compressed air supply chamber 30 from the trigger 42 side.
Trigger valve cylinder 45 having a through hole leading to the inside
a, 45b, a pilot valve 47 having a through hole 46 slidably inserted into the trigger valve cylinders 45a, 45b and having the same direction as the through hole, and a through hole of the trigger valve cylinder 45a and a through hole of the pilot valve 47. The stem 48 is inserted across the hole 46 and has a front portion projecting toward the trigger 42.

The trigger valve cylinders 45a and 45b are provided with a first pilot air chamber 49 and a return air chamber 29 having a diameter larger than that of the first pilot air chamber 49 from the front to the rear in the through holes. A second pilot air chamber 50 connected via a passage 65, a through hole 51 to the atmosphere, and the main valve chamber 4 via the air passage 44.
The communication hole 52 connected to 1 is sequentially formed.

The pilot valve 47 has a first piston portion 53 corresponding to the first pilot air chamber 49 and a second piston portion 54 corresponding to the second pilot air chamber 50 from the front portion to the rear portion thereof. A valve portion 55 and a compressed air supply chamber 30 side that communicate the communication hole 52 with the conduction hole 51 through the through holes of the trigger valve cylinders 45a and 45b when the pilot valve 47 moves forward and with the compressed air supply chamber 30 side when the pilot valve 47 moves backward. A third piston portion 56 having a diameter smaller than that of the first piston portion 53 exposed to the outside is sequentially formed.

The valve portion 55 of the pilot valve 47 has a second
Has an annular recess 57 corresponding to the communication hole 52 formed between the piston part 54 and the third piston part 56,
O-rings 58 and 59 are fitted on both sides thereof, respectively. A valve seat is provided in the through hole of the trigger valve cylinder 45b corresponding to each O-ring 58,59. When the pilot valve 47 moves forward, the rear O-ring 59 blocks the communication hole 52 from the compressed air supply chamber 30 side, and the front O-ring 58 connects the communication hole 52 to the communication hole 5.
When the pilot valve 47 is retracted, the rear O-ring 59 conducts the communication hole 52 to the compressed air supply chamber 30 side, and the front O-ring 58 connects the communication hole 52 to the communication hole 5.
It will be cut off from 1.

When the stem 48 advances toward the trigger 42 side, the first pilot air chamber 49 is electrically connected to the compressed air supply chamber 30 through the through hole 46 of the pilot valve 47, and the trigger 42 is pulled. A valve portion 60 is provided for connecting the first pilot air chamber 49 to the atmosphere through the through hole of the trigger valve cylinder 45a when retracting.

This valve portion 60 is provided in the trigger valve cylinder 4
The O-ring 61 for opening and closing the inside of the through hole of 5a and the first pilot air chamber 49, and the pilot valve 4
7 through hole 46 and first pilot air chamber 49
And an O-ring 62 that opens and closes between and.

The stem 48 is the pilot valve 4
Compression coil spring 6 inserted in through hole 46
It is always urged forward by 3. Due to the urging force, the front portion of the stem 48 causes the trigger valve cylinder 45a.
It projects from its through hole in front of.

A trigger 42 for pushing the stem 48 backward is in contact with the front portion of the stem 48. The trigger 42 is pivotally supported by a pin 64 on the front side of the portion of the housing 20 where the trigger valve 43 is located, and is rotated downward.

Next, a series of operations of the driving tool of the above embodiment will be described. First, as shown in FIGS. 1 and 2, when the trigger 42 is not yet being pulled, the stem 48 is located at the front end, and the O-ring 61 on the front side thereof is in close contact with the inner surface of the through hole of the trigger valve cylinder 45a. First
The pilot air chamber 49 is shut off from the atmosphere. On the other hand, the compressed air from the compressed air supply chamber 30 is flowing into the first pilot air chamber 49 through the through hole 46 of the pilot valve 47, and the pressure thereof is the first.
Acting on the piston portion 53 of the. Since the diameter of the first piston portion 53 is larger than the diameter of the third piston portion 56, the pilot valve 47 is located at the rear end. Therefore, the front O-ring 58 of the valve portion 55 of the pilot valve 47 blocks the communication hole 52 from the communication hole 51, and the rear O-ring 59 makes the communication hole 52 conductive to the compressed air supply chamber 30. The chamber 41 is filled with compressed air.
As a result, the main valve 35 closes the rear portion of the cylinder 21 and disconnects the compressed air supply chamber 30 from the inside of the cylinder 21.

Next, as shown in FIGS. 3 and 4, when the trigger 42 is pulled, the stem 48 is retracted, and the rear O-ring 62 of the valve portion 60 of the stem 48 is inserted into the through hole 46 of the pilot valve 47. The front O-ring 61 comes into contact with the inner surface and separates from the inner surface of the through hole of the trigger valve cylinder 45a.
Therefore, the compressed air in the first pilot air chamber 49 passes through the gap between the inner surface of the through hole of the trigger valve cylinder 45a and the stem 48 and is discharged into the atmosphere. Then, the pilot valve 47 advances due to the pressure applied to the third piston portion 56.

As a result, as shown in FIGS. 5 and 6, the rear O-ring 5 of the valve portion 55 of the pilot valve 47.
9 closely adheres to the inner surface of the through hole of the trigger valve cylinder 45b and shuts off the communication hole 52 from the compressed air supply chamber 30. At the same time, the front O-ring 58 of the valve portion 55 of the pilot valve 47 connects the communication hole 52 to the conduction hole 51. For this reason,
The compressed air in the main valve chamber 41 is discharged to the atmosphere through the passage 44, the communication hole 52, and the conduction hole 51. As a result, the main valve 35 separates rearward from the rear end portion of the cylinder 21 due to the air pressure in the compressed air supply chamber 30 acting on the left end surface thereof,
Compressed air flows into the piston rear cylinder chamber 21a in the cylinder 21 through the gap. The piston 23 is rapidly advanced by the compressed air, and the driver 22 drives the stopper 27 into the driven material 66.

Then, as shown in FIGS. 7 and 8,
When the piston 23 passes through the communication passage 31, the compressed air in the piston rear cylinder chamber 21 a flows from the communication passage 31 into the return air chamber 29. On the other hand, the second of the trigger valve 43
Since the pilot air chamber 50 of No. 2 communicates with the piston front cylinder chamber 21b and the return air chamber 29 via the passage 65, the pilot valve 47 retracts due to the increase in the pressure of the return air chamber 29, and the front O-ring of the valve portion 55. 58 blocks the communication hole 52 from the conduction hole 51, and the rear O-ring 59
Separates from the inner surface of the through hole of the trigger valve cylinder 45b and guides the compressed air in the compressed air supply chamber 30 to the main valve chamber 41 through the communication hole 52 and the passage 44. When the pressure in the main valve chamber 41 rises, as shown in FIGS. 9 and 10,
The main valve 35 moves forward to shut off between the compressed air supply chamber 30 and the piston rear cylinder chamber 21a, and the valve portion 40
Open. Therefore, the piston rear cylinder chamber 21a
The compressed air inside is discharged to the atmosphere from between the valve portion 40 and the valve seat 39. Therefore, the piston 23 is returned to the rear end by the compressed air in the piston front cylinder chamber 21b. With the return of the piston 23, the compressed air in the piston front cylinder chamber 21b expands, the pressure becomes lower, and the compressed air is released to the atmosphere from the gap between the driver 22 integrally attached to the piston 23 and the guide cylinder 25. Therefore, the pressure in the second pilot air chamber 50 also decreases, and the pilot valve 47
Is the compressed air supply chamber 3 added to the third piston portion 56.
It moves forward by the pressure of the compressed air of 0, and the fastener 27 is driven into the driven material 66 in the same manner as described above.

When the trigger 42 is released, as shown in FIGS. 1 and 2, the stem 48 is moved back by the compressed air introduced into the through hole 46 of the pilot valve 47 and the spring 63. As the stem 48 returns, the front O-ring 61 of the valve portion 60 of the stem 48 moves toward the trigger valve cylinder 45.
The rear O-ring 62 comes into close contact with the inner surface of the through hole of a and the rear O-ring 62 separates from the inner surface of the through hole 47 of the pilot valve 47, and guides the compressed air in the compressed air supply chamber 30 into the first bilot air chamber 49. As a result, the pilot valve 47 retracts to the right end, guides the compressed air in the compressed air supply chamber 30 into the main valve chamber 41, moves the main valve 35 forward, and stops the repetition of the driving operation.

[0037]

Since the present invention has the above-described structure, compressed air does not flow into the main valve chamber during the retreat of the main valve. Therefore, the decompression speed of the main valve chamber is increased, It speeds up the operation of the main valve and allows a momentary large amount of compressed air to flow into the cylinder chamber behind the piston.
The driving speed and driving force of the stopper can be increased.

Further, unlike the conventional case, since it is not necessary to provide the repetitive valve independently, the structure can be simplified accordingly.

[Brief description of drawings]

FIG. 1 is a partially cutaway vertical cross-sectional view of a driving tool equipped with an automatic repeater according to the present invention in a state in which a trigger is not pulled.

FIG. 2 is an enlarged cross-sectional view of a main part in FIG.

FIG. 3 is a partial cutaway vertical sectional view immediately after pulling a trigger of the driving tool.

FIG. 4 is an enlarged sectional view of a main part in FIG.

FIG. 5 is a partial cutaway vertical cross-sectional view in a state where the trigger of the driving tool is pulled to drive the hammer.

FIG. 6 is an enlarged cross-sectional view of a main part in FIG.

FIG. 7 is a partial cutaway vertical sectional view immediately before a piston returning operation of the driving tool.

FIG. 8 is an enlarged cross-sectional view of a main part in FIG.

FIG. 9 is a partial cutaway vertical sectional view during a piston returning operation of the driving machine.

10 is an enlarged cross-sectional view of a main part in FIG.

FIG. 11 is a vertical sectional view of the entire driving tool.

FIG. 12 is a vertical sectional view of a main part of a conventional driving machine.

FIG. 13 is a vertical sectional view of an essential part of another conventional driving machine.

[Explanation of symbols]

 21 ... Cylinder 22 ... Driver 23 ... Piston 29 ... Return air chamber 30 ... Compressed air supply chamber 35 ... Main valve 41 ... Main valve chamber 42 ... Trigger 43 ... Trigger valve 45a, 45b ... Trigger valve cylinder 46 ... Through hole 47 ... Pilot Valve 48 ... Stem 49 ... First pilot air chamber 50 ... Second pilot air chamber 51 ... Conduction hole 52 ... Communication hole 53 ... First piston part 54 ... Second piston part 55 ... Valve part 56 ... Third Piston part

Claims (1)

[Claims] 1. A cylinder containing a piston for holding a driver, and a main valve for reciprocating the piston by selectively connecting a rear end portion of the cylinder with the atmosphere or the compressed air supply chamber side to reciprocate the piston. In an automatic repeater of a driving machine, comprising: a trigger valve for switching supply and discharge of compressed air for opening and closing the main valve to a main valve chamber for operating the main valve, wherein the trigger valve is provided from a trigger side. A trigger valve cylinder having a through hole communicating with the inside of the compressed air supply chamber, a pilot valve having a through hole in the same direction as the through hole slidably inserted into the trigger valve cylinder, and the trigger valve cylinder Inserted across the through hole and the through hole of the pilot valve,
The front part has a stem protruding toward the trigger, and the trigger valve cylinder is connected to the first pilot air chamber and the return air chamber of the cylinder from the front part to the rear part in the through hole. A second pilot air chamber, a communication hole to the atmosphere, and a communication hole connected to the main valve chamber are sequentially formed, and the pilot valve corresponds to the first pilot air chamber from its front part to its rear part. The first piston portion, the second piston portion corresponding to the second pilot air chamber, and the pilot hole when the pilot valve advances, the communication hole is conducted to the conduction hole through the communication hole of the trigger valve cylinder, and compressed when retracted. A valve portion that is electrically connected to the air supply chamber and a third piston portion that has a smaller diameter than the first piston portion that is exposed to the compressed air supply chamber side are sequentially formed. , The first pilot air chamber is connected to the compressed air supply chamber through the through hole of the pilot valve when the stem moves forward to the trigger side, and the first pilot air chamber moves when the backward movement is caused by the trigger pulling. An automatic repeater for a driving machine, characterized in that a valve section is provided for conducting to the atmosphere through a through hole of a trigger valve cylinder.