JPH068157A - Pneumatic type fixture driving machine - Google Patents

Abstract

PURPOSE:To provide a fixture driving machine which can shorten extremely the axial length of a main valve and a main cylinder. CONSTITUTION:A main valve 15 consists of a seal portion 29 that extends to a narrow opening between the upper end portion of a main cylinder 10 and the inner surface of a housing 2 and butts against the housing surface; a slide portion 30 that extends from the seal portion 29 to the outer periphery of the main cylinder 10 and slides the outer periphery of the main cylinder 10 in its axial direction; and the pressure receiving portion 31 of a large diameter which is formed by the slide portion 30 and arranged at a control chamber 32 that receives control air from a trigger valve 16. At each main cylinder 10, an exhaust passage 35 that passes the lower part side surface from the upper end portion and passes through the exhaust hole 36 of the housing 2, is formed, and the inlet of the exhaust passage 35 at the upper end portion of each main cylinder is sealed by means of the seal portion 29 of each main valve 15 when each main valve 15 is in a discharge position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic fastener-driving machine such as a nail driver, and more particularly to a pneumatic fastener-driving machine capable of nailing a narrow portion such as a Japanese-style ceiling.

[0002]

2. Description of the Related Art Pneumatic fixing tool driving machine for driving a striking member such as a blade by a piston / cylinder device to drive a fixing tool such as a nail to a driving target such as wood by using pressurized air. Is extremely well known. A typical structure of this pneumatic fastener driving machine is a housing that stores pressurized air, a main cylinder in the housing, a reciprocating movement in the main cylinder, and a fixed lower nose. A main piston to which a driving member for striking the tool is connected, a stationary position provided above the main cylinder to prevent the supply of pressurized air to the main cylinder, and a cylinder chamber above the main piston from the upper part of the main cylinder. A main valve that moves between a firing position that supplies pressurized air and a main valve that moves the main valve to the rest position when not pushed and the main valve to the firing position when pushed. And a trigger device for controlling the.

In the fastener driving machine having such a structure, by pushing the trigger valve of the trigger device, the main valve in the stationary position is moved to the firing position to rapidly move the main piston to the lower nose side. Next, by returning the trigger valve, the main valve that was in the firing position was moved to the rest position to stop the supply of pressurized air to the cylinder chamber above the main piston, and to restore between the main cylinder and the housing. Pressurized air is supplied from the pressurized air reservoir to the cylinder chamber below the main piston to return the main piston.At the time of this return, the air in the cylinder chamber above the main piston is exhausted to the outside of the housing. At that time, I am sending the next fixture to the nose.

Since such a fastener driving machine is convenient and convenient, it is widely used in construction sites. By the way, at a construction site, using these fastener driving machines, in order to be able to drive fasteners such as nails into a target to be driven such as wood in a desired position and posture, Need space for hands and bodies to hold. In the case of walls, etc., it is often possible to secure a sufficient space, but for example, the space above the ceiling, and especially the part with the pillar of the rim where the end of the Japanese style ceiling plate is placed in the Japanese style ceiling by modern construction method It is extremely narrow, and none of the fastener driving machines to date are small enough to drive in that space. In particular, the conventional fastener driving machine requires a certain length in the axial direction of the main cylinder, and the length in this direction cannot be shortened. Therefore, there is an inconvenience that the driving machine cannot be used.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a fastener driving machine in which the length of the main cylinder in the axial direction can be extremely shortened to shorten the length of the driving machine body.

[0006]

In order to achieve the above object, according to the present invention, in the above-mentioned conventional pneumatic fastener driving machine, the main valve includes an upper end portion of the main cylinder and an inner surface of the housing. A seal portion extending in a narrow gap between the main cylinder and the housing surface, and a slide portion extending from the seal portion to the outer circumference of the main cylinder to slide the outer circumference of the main cylinder in the axial direction. And a large-diameter pressure receiving portion arranged in a control chamber that receives control air from the trigger valve, and an exhaust passage is formed in the main cylinder from the upper end portion through the lower side surface to the exhaust hole of the housing. The inlet of the exhaust passage at the upper end of the main cylinder can be sealed by the sealing part of the main valve when the main valve is in the firing position. Pneumatic fastener driving machine, characterized in that provided in the position is provided. Due to this feature, most of the main valve is now provided on the outer circumference of the main cylinder, so the main valve portion that has greatly extended in the length direction in the conventional driving machine is almost eliminated, and the main piston and blade are made in Japanese style. The length of the main cylinder in the axial direction can be extremely shortened by shortening it according to the length of a fixture such as a nail used on the ceiling or the like, and the entire nose can be made extremely short by shortening the nose.

Further, according to the present invention, in the fastener driving machine having the above-mentioned structure, the upper end of the safety arm for enabling the operation of the trigger device by pressing it against the object to be driven and the trigger lever of the trigger device. A pin is provided on the housing that extends to prevent upward movement of the arm between the trip lever for enabling movement, which pin is normally in the retracted position and is located in the main piston. A pneumatic fastener driving machine is provided which is extended so as to be engaged with a safety arm by an exhaust pressure of an exhaust passage of a main cylinder at the time of returning to prevent upward movement of the safety arm. . This driving machine uses exhaust gas from the main cylinder to prevent double hitting of a fixture such as a nail.

Furthermore, according to the present invention, the main valve is
It is provided between the main cylinder and the trigger valve so that it can move substantially parallel to the main piston, and an air communication passage is formed between the upper surface of the main valve and the upper surface of the main cylinder. A sealing portion on the upper surface side for sealing the compressed air of the housing so as not to flow into the communication passage when in the stationary position, a large diameter pressure receiving portion arranged in the control chamber for receiving the control air from the trigger valve, and the upper surface From the side to the lower surface side and sends the air from the air communication passage to the exhaust hole of the housing, and when the main valve is in the stationary position, the air in the cylinder chamber above the main piston is The lower surface of the main valve is connected to the outside of the housing through the air communication passage and the through hole, and when the main valve is in the firing position. Fastener driving machine, characterized in that contact with the through hole is sealed to the face is provided.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a nailing machine 1 as a pneumatic fastener driving machine has a housing 2 for storing pressurized air. The housing 2 includes a body portion 3 (left side portion in the drawing) on which a piston / cylinder device is provided, and a trigger device 4.
And a handle portion 5 (the right side portion in the figure) provided with a nose 7 for driving a nail as a fixture is integrally provided on the lower portion of the main body portion 3. Further, the nose 7 is provided with a nail feeding portion 8 on the right side of the drawing, and a nail (one not shown) is fed to the nose 7 one by one from a magazine (not shown) for winding and accommodating a continuous body of nails in a coil shape. It will be sent.

In the main body portion 3 of the housing 2, a main cylinder 10 and a main piston 10 which is arranged so as to reciprocate in the main cylinder and to which a blade 11 as a driving member for hitting a nail in the nose 7 is connected. And 12 are provided. A main valve 15 according to the present invention is provided between the main cylinder 10 and a pressurized air chamber 13 formed in the housing 2, and controls supply and stop of pressurized air to the main cylinder 10. To be done. For such control, the main valve 15 has a stationary position (position in FIG. 1) that blocks the supply of pressurized air to the main cylinder 10,
Firing position (position in FIG. 2) for supplying pressurized air from the upper part of the main cylinder to the cylinder chamber above the main piston 12.
Move between and. The main valve 15 is controlled by the trigger valve 16 of the trigger device 4.

The trigger valve 16 is a valve cylinder 17
And a valve piston 18, and the valve piston 18
Is a firing position (position in FIG. 2) in which a lower position is lowered (position in FIG. 1) and a lower end thereof is pushed up by a trigger lever 19 and a trip lever 20 pivotally supported by a tip of the trigger lever. It can be moved between and. In a normal state, that is, when the valve piston 18 is not pushed, the valve piston 18 is in a rest position in which the valve piston 18 is lowered, and the pressurized air in the pressurized air chamber 13 is discharged from the hole 22 at the upper end of the valve cylinder 17 into a gap between the valve piston 18 and the valve cylinder 17. Through the passage 23. When the valve piston 18 is pushed up to the firing position, that is, to the upper position, the hole 22 passes through the passage 23.
The supply of the pressurized air to the air is stopped, and the air in the passage 23 is released to the atmosphere through the second hole 24 in the lower portion of the valve cylinder 17 (see FIG. 2).

The main valve 15 is controlled by the operation of the trigger valve 16. That is, when the trigger valve 16 is in the resting state (resting position state) in FIG. 1, the main valve 15 is in the resting position, and when the trigger valve 16 is pushed next, the main valve 15 in the resting position is Main piston 1 moved to the firing position
The blade 11 connected to 2 is rapidly moved to the lower nose side and the nail in the nose 7 is driven into the driving target. Then, as shown in FIG. 3, by returning the trigger valve 16, the main valve 15 in the firing position is returned to the rest position in FIG. The more detailed structure and operation of the main valve 15 will be described later.

The trip lever 20, which is pivotally supported on the tip of the trigger lever 19 of the trigger device 4, is in an invalid position away from the lower end of the trigger valve piston 18 when the tip is in a lowered state (see FIG. 1). Therefore, even if the trigger lever 19 is pulled up by a finger or the like, the trigger valve piston 18 is not pushed up. This trip lever 20
It is the safety arm 26 that extends from the lower end of the nose 7 toward the trip lever 20 that brings the to the effective position. When the lower end of the nose 7 is pressed against the object to be driven, the safety arm 26 translates upward from the state of FIG. 1 as shown in FIG. 2, and its upper end portion 27 abuts on the tip of the trip lever 20. Touch and push up. As a result, the safety arm 26
Functions as a safety device that operates the trigger valve only when the nose is pressed against the driving target and invalidates the trigger operation when the nose is not pressed against the driving target.

In the present invention, the main valve 15 is
A seal portion 29 extending into a narrow gap between the upper end of the main cylinder 10 and the inner surface of the housing 2 and abutting the housing surface, and the seal portion 29 to the main cylinder 10
The slide portion 30 extends to the outer periphery of the main cylinder and slides the outer periphery of the main cylinder in the axial direction, and a large-diameter pressure receiving portion 31 formed on the lower side of the slide portion 30. The pressure receiving portion 31 is arranged in a control chamber 32 that communicates with the passage 23 so as to receive the pressurized air controlled by the trigger valve 16. The diameter of the pressure receiving portion 31 is formed larger than the diameter of the sealing portion 29, and the pressure receiving area of the pressure receiving portion is wider than that of the sealing portion 29. Therefore, when the pressurized air is supplied from the trigger valve 16 to the pressure receiving portion 31 in the control chamber 32 and the pressurized air in the housing is also applied to the seal portion 29, the pressure receiving portion 31 is strongly pushed up,
The state of FIG. 1 is maintained. The spring 33 provided to push up the pressure receiving portion 31 is weak enough to prevent the main valve 15 from rattling when there is no pressurized air in the housing 2, and is not essential.

In the present invention, the main valve 15 is provided not on the upper side of the main cylinder but on the outer peripheral side of the main cylinder to shorten the axial length of the main body portion 3. Further, the main cylinder 10 also has a short axial length according to the length of the nail to be used, and the blade 11 connected to the main piston is also short. Furthermore, the nose 7 is also shortened according to the length of the nail used,
As a result, the entire nail driver is made extremely small.
In the present invention, the main cylinder 10 has
An exhaust passage 35 for exhausting the cylinder chamber above the piston when the main piston 12 returns is formed from the upper end portion toward the lower side surface, and the exhaust passage 35 communicates with an exhaust hole 36 formed on the side surface of the housing 2. ing. The upper end (inlet) of the exhaust passage 35 is sealed by the sealing portion 29 of the main valve 15 (see FIG. 2).

In the illustrated example, two exhaust passages 35 are formed in the main cylinder 10, but one exhaust passage 35 is sufficient. Further, as in the example shown on the right side of the drawing, the exhaust gas discharged from the exhaust passage 35 can be further utilized through the exhaust hole 36 of the housing 2. That is, the exhaust hole 36
The upper part 2 of the safety arm 26 on the outer part of the housing of
7 and the trip lever 20 there is provided a pin 38 which extends so as to prevent upward movement of the arm, which pin is normally biased by a spring 39 so that it is in the retracted position. ing. An air passage 40 communicating with the exhaust passage 35 extends at the rear end (left end in the figure) of the pin 38, and the pin 38 is extended by the exhaust pressure. In addition, the tip portion 2 of the safety arm 26
A notch 41 that receives the tip of the pin 38 is formed in the pin 7. A throttle valve 42 may be provided on the lower end side of the air passage 40 to adjust the air pressure applied to the pin 38.

Inside the lower portion of the main body portion 3 of the housing 2, a return pressurized air reservoir 4 is provided between the main cylinder 3 and the main cylinder 10.
4 are formed. In the air reservoir 44, air is stored in a compressed state when the main piston 12 descends,
When the main piston returns to the rest position, the pressurized air in the cylinder chamber above the piston is discharged to the outside of the housing. Therefore, compressed air is supplied from the hole 45 to the cylinder chamber below the main piston to return the main piston 12 upward. . In this return, a cylindrical projecting portion 47 is formed on the inner surface of the upper part of the housing so that the inner surface of the housing will not be damaged even if the main piston 12 impacts the upper surface of the housing 2, and the surface of the cylindrical projecting part 47 is formed. A cushion 48 is provided.

Further, the sealing portion 29 of the main valve 15
Is formed with a ring-shaped protruding portion 50 with respect to the inner surface of the housing above it, and the protruding portion 5 is also formed on the inner surface of the housing.
A ring-shaped projecting portion 51 that closely contacts the side surface of 0.
Are formed. These protruding portions 50 and 51 are
When the main valve 15 is in the state shown in FIG. 1, the pressurized air in the housing is prevented from leaking to the main cylinder 10. When the main valve 15 moves from the position shown in FIG. 1 to the position shown in FIG. 2, both ring shapes are formed until the sealing portion 29 of the main valve 15 seals the inlet of the exhaust passage 35 at the upper end of the main cylinder 10. Protruding part 50
The tightness or seal of 51 and 51 is maintained.

In the operation of the nailing machine 1 having such a configuration, in the stationary state of FIG. 1, the pressurized air supplied to the inside of the housing 2 passes through the trigger valve 16 of the trigger device 4 from the passage 23 to the control chamber 32. Supplied and main valve 15
Push up the pressure receiving portion 31 of. As a result, the supply of pressurized air to the main cylinder 10 is blocked, and the pressure of the pressurized air does not act on the upper surface of the main piston 12. Therefore,
The main piston 12 and the blade 11 are maintained in the state of FIG.

Next, the firing state will be described with reference to FIG. The lower end of the nose 7 is pressed against the driving target to push up the safety arm 26 so that the upper end portion 27 pushes up the tip of the trip lever 20 of the trigger device 4 to the effective position. When the trigger lever 19 is pulled in this state, the lower end of the valve piston 18 is pushed up, the supply of pressurized air to the valve cylinder is stopped, and the air in the control chamber 32 passes from the passage 23 through the trigger valve 16 to the atmosphere through the hole 24. Exhausted to.
As a result, the pushing force of the pressurized air on the pressure receiving portion 31 of the main valve 15 disappears, while the sealing portion 29
Since the pressurized air to the main valve 15 is still added, the main valve 15 is lowered downward, the seal between the seal portion 29 and the inner surface of the housing 2 is released, and the pressurized air is rapidly supplied to the upper portion of the main cylinder 10. Then, the main piston 12 and the blade 11 are rapidly pushed down, and the nail in the nose 7 is driven into the object. At the time of this driving, the air below the main piston 12 is sent to the return pressurized air reservoir 44 from the holes 45 and 53, and further, after the main piston 12 reaches the bottom dead center, the air in the housing 2 passes through the hole 53. The pressurized air inside is supplied to the return pressurized air reservoir 44. The pressurized air in the reservoir 44 is the O-ring 5 as a check valve.
4 does not leak from the hole 53.

When the nose 7 is separated from the object to be driven and the trigger lever 19 is released, the state returns to the return state shown in FIG. Depending on whether the safety arm 26 is lowered or the trigger lever 19 is released, the trip lever 20 lowers and the valve piston 18 lowers, so that the pressurized air inside the housing 2 passes through the valve cylinder 17 and the passage 23 to the main valve 15 of the main valve 15. Pressurized air is supplied to the pressure receiving portion 31. As a result, the main valve pushing force applied to the pressure receiving portion 31 becomes larger than the main valve pushing force exerted on the seal portion 29 of the main valve 15, pushing up the main valve 15 and the seal portion 29 is placed on the inner surface of the housing 2. The supply of pressurized air to the main cylinder 10 is shut off in close contact. At the same time, the seal portion 29 of the main valve 15 opens the inlet of the exhaust passage 35 of the main cylinder 10 to communicate the upper cylinder chamber of the main piston 12 with the atmosphere. On the other hand, since pressurized air is supplied from the return pressurized air reservoir 44 through the hole 45 to the cylinder chamber on the lower surface side of the main piston 12,
The main piston 12 rises. At this time, the air in the cylinder chamber on the upper side of the main piston 12 is exhausted through the exhaust passage 35. This exhaust gas also passes through the air passage 40, and the pressure thereof causes the pin 38 to extend toward the upper end portion 27 of the safety arm 26 and enter the notch 41 to prevent the arm tip portion 27 from contacting the trip lever 20. Prevents double impact due to recoil. Further, the main piston 12 that returns to the ascending position has the cushion 4 at the top dead center.
The shock is softened by 8 and the state returns to the stationary state shown in FIG.

When the main valve 15 moves from the rest position shown in FIG. 1 to the firing position shown in FIG.
The ring-shaped protruding portion 50 is in close contact with the side surface of the ring-shaped protruding portion 51 of the housing 2 to maintain the sealing until the seal portion 29 of 5 seals the inlet of the exhaust passage 35 at the upper end of the main cylinder 10. Therefore, the loss of pressurized air when transitioning from the stationary state to the firing state is minimized.

4 and 5 show a nailing machine 60 according to a second embodiment of the present invention. In the nailing machine 60, a main valve 61 is provided at a position between a main cylinder 62 and a trigger valve 63 so that the main valve 61 can move substantially parallel to the main piston 64. It is basically the same as the nailing machine 1 of the first embodiment except that it is exhausted through 61.

That is, the main valve 61 of the nail driver 60
Is provided at the tip of the handle, and the main valve 61 is connected to the main cylinder 62 at the tip of the handle.
The main piston 6 at an intermediate position between the trigger valve 63 and
The housing 67 is integrally assembled to form a part of the housing 67 so as to have an axis 66 that is substantially parallel to the axis 65 of No. 4. The blade 68 attached to the main piston is slightly displaced to the left side of the figure from the main piston axis 65 so that a narrow portion such as a corner can be driven. Further, a cushion material 69 is preferably provided on the upper surface of the main piston 64. Furthermore, nail driver 6
At 0, an air communication passage 70 is formed in the portion of the housing 67 between the upper surface of the main valve 61 and the upper surface of the main cylinder 62.

When the main valve 61 is in the rest position shown in FIG. 4, the main valve 61 seals the compressed air from the compressed air chamber 72 in the housing 67 so as not to flow into the air communication passage 70.
Therefore, the main valve 61 is provided with a seal portion, that is, a sealing O-ring 73 on the upper surface side thereof.
Further, the main valve 61 is provided with a pressure receiving portion 75 arranged in an intermediate position in a control chamber 74 that receives control air from the trigger valve 63, and the pressure receiving area of this pressure receiving portion 75 is larger than the pressure receiving area of the valve upper surface. When the pressurized air from the pressurized air chamber 72 is applied to the pressure receiving portion and the valve upper surface, the main valve 61 is pushed upward, that is, to the rest position in FIG. When there is no pressurized air in the control chamber 74, the pressurized air applied to the upper surface of the main valve pushes it down to the firing position of FIG. Further, the main valve 61 is formed with a through hole 76 penetrating from the upper surface side to the lower surface side. The through hole 76 communicates the main cylinder 62 with the exhaust hole 77 of the housing 67 through the air communication passage 70, and exhausts air from the cylinder chamber above the main piston to the atmosphere.

The housing 6 on the lower surface side of the main valve 61
Sealing material 79 is provided on the surface of No. 7, and when the main valve 61 is in the firing position in FIG. 5, the lower surface of the main valve abuts the sealing material 79 on the housing surface to seal the through hole 76. The main valve 61 and the housing 6
A spring 80 is provided in the control chamber 74 between 7 and 7 so as to push up the pressure receiving portion 75, but it is weak enough to prevent the main valve 61 from rattling in the absence of pressurized air. It is not mandatory. Further, it is convenient that the main valve 61 and the housing and the control chamber 74 around the main valve 61 are configured as one unit and can be attached to and removed from the nailing machine 60 as a unit.

In the operation of the nail driver 60, when the nose 82 is pressed against the object to be driven and the safety arm (not shown) is pushed up, the trigger valve 63 is pulled from the rest position in FIG. 4 to the firing position. The supply of the pressurized air from the control chamber 74 to the control chamber 74 is stopped, and the pressurized air in the control chamber 74 is exhausted from the trigger valve 63, so that the main valve 61
The pushing force of the pressurized air to the pressure receiving portion 75 of the above is lost. On the other hand, since pressurized air is still being applied to the upper surface side of the main valve 61, the main valve 61 is lowered downward, the sealing O-ring 73 is separated from the valve seat surface of the housing 67, and the seal is released. The lower surface of the main valve 61 is in close contact with the sealing material 79 and the through hole 76
To prevent the pressurized air from coming out from the exhaust hole 77. As a result, pressurized air is supplied to the air communication passage 70 from the pressurized air chamber 72, and the pressure of the pressurized air acts on the upper surface of the main piston 64 to rapidly push down the main piston 64 and the blade 68, and the nose. The nail at 82 is driven into the object. At this time, the air in the cylinder chamber below the main piston 64 and the pressurized air in the cylinder chamber above the main piston are accumulated in the return pressurized air reservoir 83.

When the nose 82 is separated from the object to be driven and the trigger valve 63 is returned, the stationary state shown in FIG. 4 is restored. That is, when the pressurized air is supplied to the control chamber 74, the main valve pushing force applied to the pressure receiving portion 75 becomes larger than the main valve pushing force acting on the upper surface side of the main valve 61, and the main valve 61 is turned on. When pushed up, the O-ring 73 comes into close contact with the valve seat surface of the housing 67 to shut off the supply of pressurized air to the main cylinder 62. At the same time, the lower surface of the main valve separates from the sealing material 79 and allows the through hole 76 to communicate with the exhaust hole 77, so that the air in the cylinder chamber on the upper side of the main piston 64 passes through the air communication passage 70 and the through hole 76 and the housing. Exhausted to the outside. The shock of the main piston 64 returning to the ascending position is softened by the cushion 69 at the top dead center, and the main piston 64 returns to the stationary state shown in FIG.

[0029]

According to the present invention, most of the main valves can be installed on the outer peripheral side of the main cylinder, and the exhaust passage is formed in the main cylinder. Therefore, in the conventional fastener driving machine, the main valve extends greatly in the longitudinal direction. The main valve part has almost disappeared, and the length of the fastener driving machine can be greatly shortened.
By shortening the main cylinder and the blade, the axial length of the piston / cylinder device can be shortened, and by shortening the nose, the entire driving tool can be made extremely short. Therefore, the driving operation can be easily performed even in a narrow space such as a Japanese-style ceiling. Further, according to the present invention, since the exhaust hole is provided on the outer peripheral side of the main cylinder, the setting of the exhaust passage is facilitated, and the pin is provided in the exhaust hole portion on the side surface of the housing communicating with the exhaust passage of the main cylinder. Provided, the exhaust pressure can be used to project the pin so as to prevent upward movement of the arm between the upper end of the safety arm and the trip lever that enables the operation of the trigger device, thereby allowing the fixture to It is possible to prevent double hitting. In addition, a ring-shaped protruding portion is formed on the seal portion of the main valve and the inner surface of the housing above it that are in close contact with each other on both sides, preventing pressurized air in the housing from leaking to the main cylinder when in the stationary position. Therefore, even when the main cylinder moves from the stationary position to the firing position, loss of pressurized air can be prevented.

Further, according to the present invention, the main valve is
Fixing tool is installed between the main cylinder and the trigger valve so that it can move almost parallel to the main piston, and the air from the cylinder chamber above the main cylinder piston can be exhausted through the main valve. According to this driving machine, the main cylinder portion can be made shorter and thinner, and the main valve portion that has greatly extended in the length direction in the conventional fastener driving machine is further shortened and thinner. Yes, if the nose is shortened, the entire driving tool can be made extremely short. Therefore, the driving operation can be easily performed even in a narrow space such as a Japanese-style ceiling.

[Brief description of drawings]

FIG. 1 is a sectional front view of a nailing machine as a fixture driving machine according to the present invention in a stationary position.

FIG. 2 is a sectional front view of a firing position of a nail driving machine as a fastener driving machine according to the present invention.

FIG. 3 is a cross-sectional front view of the nail driving machine as the fastener driving machine according to the present invention at the time of returning.

FIG. 4 is a sectional front view of a nail driving machine as a fixture driving machine according to a second embodiment of the present invention in a stationary position.

FIG. 5 is a sectional front view of a firing position of a nail driving machine as a fastener driving machine according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nail driver 2 Housing 3 Main body part 4 Trigger device 5 Handle part 7 Nose 8 Nail feeding part 10 Main cylinder 11 Blade 12 Main piston 13 Pressurized air chamber 15 Main valve 16 Trigger valve 17 Valve cylinder 18 Valve piston 19 Trigger lever 20 Trip lever 23 Passage 26 Safety arm 27 Arm tip part 29 Seal part 30 Sliding part 31 Pressure receiving part 32 Control chamber 35 Exhaust passage 36 Exhaust hole 38 Pin 40 Air passage 44 Pressurized air reservoir for return 50, 51 Ring-shaped protruding part 60 Nailing machine of the second embodiment 61 Main valve 62 Main cylinder 63 Trigger valve 64 Main piston 70 Air communication passage 73 Sealing O-ring 74 Control chamber 75 Pressure receiving portion 76 Through hole 77 Exhaust hole 79 Sealing material

Claims (3)

[Claims] 1. A housing for storing pressurized air, a main cylinder in the housing, and a driving member which is arranged so as to reciprocate in the main cylinder and which strikes a fixing tool in a lower nose are connected. Do not push the main piston and the main valve that moves between the rest position that blocks the supply of pressurized air to the main cylinder and the firing position that supplies pressurized air from the upper part of the main cylinder to the cylinder chamber above the main piston. And a trigger valve for controlling the pressurized air to the main valve so that the main valve is located at the rest position when pushed, and the main valve is located at the firing position when pushed. Move the main valve that was there to the firing position and move the main piston rapidly to the lower nose side,
Next, by returning the trigger valve, the main valve that was in the firing position was moved to the rest position to stop the supply of pressurized air to the cylinder chamber above the main piston, and to restore between the main cylinder and the housing. Pneumatic fixture that supplies pressurized air from the pressurized air reservoir to the cylinder chamber below the main piston to return the main piston, and at the time of this return, exhausts the air in the cylinder chamber above the main piston to the outside of the housing. In the driving machine, the main valve extends into a narrow gap between an upper end of the main cylinder and an inner surface of the housing, and a seal portion that abuts the housing surface, and extends from the seal portion to an outer circumference of the main cylinder. A slide part that slides on the outer circumference of the main cylinder in the axial direction and a trigger bar formed on this slide part. And a large-diameter pressure receiving portion arranged in a control chamber that receives control air from the valve, and the main cylinder has an exhaust passage formed from the upper end through the lower side surface to the exhaust hole of the housing. The pneumatic fastener driving machine is characterized in that the inlet of the exhaust passage at the upper end of the cylinder is provided at a position where it can be sealed by the seal portion of the main valve when the main valve is in the firing position. 2. A trigger device for pushing and returning a trigger valve, wherein a trigger lever that can be pulled with a finger or the like is effective, and it is effective to push up the trigger valve piston by the pulling operation of the trigger lever. And a safety arm that extends from the tip of the nose toward the trip lever and that abuts the trip lever so as to operate the trigger valve only when the nose is pressed against an object to be driven. Between the upper end of the safety arm and the trip lever, a pin is provided on the housing that extends so as to prevent the arm from moving upwards, which pin is normally in the retracted position and the main piston At the time of the return of the safety cylinder, the exhaust pressure flowing into the exhaust passage of the main cylinder extends and engages with the safety arm to extend the safety. The fastener driving machine according to claim 1, wherein the arm is prevented from moving upward. 3. A housing for storing pressurized air, a main cylinder in the housing, and a driving member arranged so as to reciprocate in the main cylinder and striking a fixing tool in a lower nose are connected. Do not push the main piston and the main valve that moves between the rest position that blocks the supply of pressurized air to the main cylinder and the firing position that supplies pressurized air from the upper part of the main cylinder to the cylinder chamber above the main piston. Sometimes the main valve is located in the rest position, and when it is pushed, it is equipped with a trigger valve that controls the pressurized air to the main valve so that the main valve is located in the firing position. Move the main valve to the firing position, move the main piston abruptly to the lower nose side, and then move the trigger bar. By returning the lube, the main valve that was in the firing position was moved to the rest position to stop the supply of pressurized air to the cylinder chamber above the main piston, and the pressurized air reservoir for return between the main cylinder and the housing In the pneumatic fastener driving machine, which supplies compressed air to the cylinder chamber below the main piston to return the main piston, and at the time of this return, exhausts the air in the cylinder chamber above the main piston to the outside of the housing. The main valve is provided between the main cylinder and the trigger valve so as to be movable substantially parallel to the main piston, and an air communication path is formed between the main valve upper surface and the main cylinder upper surface. Has been done,
The main valve has a large diameter disposed in a control chamber that receives control air from a trigger valve and a sealing portion on an upper surface side that seals the pressurized air of the housing so as not to flow into the communication passage when in the stationary position. And a through hole penetrating from the upper surface side to the lower surface side to send the air from the air communication passage to the exhaust hole of the housing. The air in the cylinder chamber communicates with the outside of the housing through the air communication passage and the through hole.When the main valve is in the firing position, the lower surface of the main valve comes into contact with the housing surface to seal the through hole. A fastener driving machine characterized by being installed.