JPH0634946Y2 - Pneumatic nailer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention uses a compressed air as a driving source to reciprocate a striking piston slidably fitted in a striking cylinder, and integrally connects to the striking piston. The present invention relates to a pneumatic nailing machine in which a nail is driven into a driven member, which is an object, by the hammer driver.

(Prior Art) Usually, a nailing machine driven by compressed air includes a striking cylinder, a striking piston accommodated in the striking cylinder so as to be reciprocally movable, and a cylinder of a nailing machine body that accommodates the striking piston. A nose forming a nail injection hole formed in a lower portion, a striking driver which is integrally coupled to a lower surface of the striking piston and is slidable in the ejection hole, and further, a main air inside the upper end side of the striking cylinder. It is composed of a chamber and a head valve that is selectively connected to the atmosphere. A nail supply opening for continuously supplying nails connected to the injection hole is formed on a side surface of the nose, and the nails connected to each other are continuously supplied to the injection hole through the opening. A nail supply mechanism is located near the opening.

In the conventional nail driving machine, the striking piston normally waits at the top dead center position of the striking cylinder, and the downward direction is caused by the compressed air pressure introduced into the striking cylinder based on the operation of the start valve that operates the head valve. The hammer is driven into the injection hole and is driven into the driven member by a hammer driver fixed to the lower surface of the hammer piston. Then, after the striking piston reaches the bottom dead center, the striking piston receives the pressure of the compressed air accumulated in the return air chamber on its lower surface side during its driving and automatically returns to the top dead center. Here, in the nails, adjacent nails are connected to each other by a plastic band or a wire, and the nails are guided and supplied along a nail supply guide which is continuously provided at one side edge of the nail supply opening to be injected into the injection hole. Are sequentially supplied to. As the nail supply mechanism, for example, a nail supply cylinder arranged along the nail supply guide, a nail supply piston housed in the cylinder, and a nail supply cylinder further attached to the tip end portion of the piston rod, A nail feed claw member engageable with the shaft of the connected nail, and is automatically supplied into the injection hole by the claw member reciprocally moved in association with the operation of the striking piston. There is.

By the way, recently, it has been demanded to carry out the construction of a roofing material called a color vest (trade name) with the above-mentioned nailing machine in order to improve work efficiency. This kind of material has a brittle property, and when it is nailed to a certain value, it breaks and a hole for nailing is formed in advance.

(Problems to be solved by the invention) However, in the structure of such a conventional nailing machine, the nails supplied into the injection hole are located inside the injection hole while being held by the connecting member. , Normally, it does not project from the tip of the nose, and the nail hole of the roof material is hidden by the lower end surface of the nose, so it is impossible to aim the nail hole accurately, so nailing it accurately into the nail hole. There was a problem that construction could not be performed.

Therefore, the present invention has been made to solve the above-mentioned problems of the prior art. The purpose of the present invention is to make the tip of the nail project from the tip of the nose for a predetermined length and drive the tip of the nail to be driven. An object of the present invention is to provide a pneumatic nailing machine that can be easily inserted into a nail hole of a member to position the nailing machine main body.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, the injection hole in the nose projecting from the nailing machine main body is reciprocated and supplied into the injection hole. A hammer driver that drives a nail from the tip of the nose, a hammer piston that integrally connects this driver, and a hammer cylinder that tightly fits the hammer piston.
A main air chamber connected to an air pressure source, and a head valve for switching between a piston upper chamber of the striking cylinder and the main air chamber or an exhaust hole,
A pneumatic nail having a trigger valve for sending an operation signal to the head valve, and nail supply means connected to each other into the injection hole through an opening formed in a side surface of the nose to continuously supply the nail. The hammer includes a cylinder mechanism that disengages the nail supplied into the injection hole from the connected state and moves the nail toward the tip of the nose, and the cylinder mechanism operates along the nail driving axis in the nose. Of the push piston, a push cylinder slidably accommodating the push piston, an extruding cylinder formed at the piston rod tip portion of the push piston, and an extruding piston slidably accommodated in the extruding cylinder. The push sill is formed at one end and includes an extruding member that can be projected and retracted in the radial direction on the nail driving axis in the nose. The inside of the binder and the inside of the extrusion cylinder are communicated with each other through a communication hole formed by penetrating the piston rod, and the push piston and the extrusion member operate in an interlocking manner. And a chuck mechanism for holding the nail moved to the tip of the nose such that the tip of the nail projects.

(Operation) In the present invention having the above-mentioned configuration, since the inside of the push cylinder and the inside of the extrusion cylinder are communicated with each other through the communication hole formed through the piston rod,
The air supplied into the push cylinder to operate the push piston is supplied into the extrusion cylinder through the communication hole, and the air pressure causes the extrusion member to project radially from the nail driving axis. Therefore, as long as the air in the pushing cylinder is not exhausted, the pushing member will be in a protruding state, so that the pushing member engages the head of the nail until after the nail is supplied by the striking driver until just before the nail is hit by the striking driver. The tip of the nail can be held so as to project, and the tip of the nail will not be pushed into the nose even if it comes into contact with the mating member when searching for the nail hole of the mating member for nailing. Therefore, the nailing position can be surely aligned, and since the nailing is performed with the nail inserted in the nail hole, the displacement between the nail and the nail hole can be prevented.

(Example) Below, this invention is demonstrated based on the Example shown in figure. First
FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of a pneumatic nailing machine of the present invention, showing a state where a striking piston is located at a top dead center. As shown in the figure, a striking cylinder 3 is provided inside the nailing machine body 1.
A striking piston 4 is slidably and tightly fitted inside the.
A striking driver 5 as a nail striking member is integrally connected to the lower surface side of the striking piston 4. Nailing machine body 1
A nose 6 is projected at the lower end of the nose 6
An injection hole 6a for guiding the hitting driver 5 is formed in the inside thereof coaxially with the hitting cylinder 3. The driving air for driving the striking piston 4 is supplied from the main air chamber 8 provided at the grip portion 7 of the nailing machine body 1 and the peripheral portion of the striking cylinder 3.

An annular head valve 9 is arranged at the upper end portion of the striking cylinder 3. The head valve 9 is a head valve piston that is slidable inside a head valve cylinder 10 that is formed in a circular shape at the upper end of the nailing machine body 1.
11 is tightly fitted. A piston stop 15 made of an elastic member is disposed further inside the head valve 9 and holds the striking piston 4 in a state where rebound is reliably prevented when the striking piston 4 returns to the top dead center.
The piston stop 15 has an overhanging portion that overhangs in the outer circumferential direction.
15a is integrally formed with the head valve piston 11 and moves up and down with the inner peripheral wall of the piston 11 to open and close with the atmosphere.

The head valve piston 11 has an opening / closing piston portion 12 for opening / closing between the main air chamber 8 and the striking piston upper chamber 4A at the lower end portion, and an operating large-diameter piston portion 13 at the upper end portion. When the head valve piston 11 is at the bottom dead center (the opening / closing piston portion 12 is in contact with the upper end edge of the striking cylinder 3 via the O-ring 14, the opening / closing piston portion 12 is located in the main air chamber 8). And the striking piston upper chamber 4A are closed, and when the inner peripheral wall communicates with the atmosphere and at the top dead center, the main air chamber 8 communicates with the striking piston upper chamber 4A. I am letting you.
A compression spring 16 is interposed between the piston stop 15 and the opening / closing piston portion 12 of the head valve piston 11, and constantly urges the head valve piston 11 toward the bottom dead center. A large number of small holes 17 are bored in the radial direction in the axially intermediate portion of the striking cylinder 3, and the check valve 19 is formed by the small holes 17 and the return air chamber 18 formed on the outer peripheral side of the striking cylinder 3. Through the.

Reference numeral 20 denotes a trigger valve provided inside the base end portion of the grip portion 7 for sending an operation signal to the head valve 9, and the passages A and B formed around the main air chamber 8 and the striking cylinder 3. A housing 21 in which a communication hole 22 that communicates with the housing 21 is formed, a pilot valve 23 attached to the housing 21 so as to be vertically movable, and a pilot valve 23.
A trigger valve stem 25 is attached to the cap 24 so as to be retractable from the inside, and a compression spring 26 that is interposed between the pilot valve 23 and the trigger valve stem 25 and biases the trigger valve stem 25 in the protruding direction. It is configured. In the initial state, a gap is formed between the housing 21 and the O-ring 29 of the pilot valve 23, and the air introduced into the main air chamber 8 by an air pressure source such as a compressor (not shown) allows the communication hole 22 from the gap. And is supplied to the passages A and B via a door valve described later.
On the other hand, when the trigger valve stem 25 is operated by pulling the trigger lever 28 upward, the pilot valve 23 is lowered and O
The ring 29 closes the gap, and the passages A and B are opened to the atmosphere through a passage 27 as an exhaust hole formed between the housing 21 and the cap 24 through the communication passage 22.

In FIG. 2, reference numeral 30 denotes a door valve connected to the trigger valve 20, which is composed of a sleeve 31 and a door valve stem 33 which is constantly urged downward by a spring 32 in the sleeve 31. A small diameter portion 33a is formed on the stem 33. By closing the opening / closing door 34, the door valve stem 33 is pushed upward to communicate with the passages A and B from the communication hole 22 of the trigger valve 20 through the small diameter portion 33a.

FIG. 3 shows a cylinder mechanism CL that dissociates the nail supplied from the injection hole 6a from the connected state and moves it toward the tip of the nose 6.
40 is a push cylinder integrally formed around the striking cylinder 3. A push piston 41 is tightly fitted in the push cylinder 40, and a push stem 42 as a piston rod is fitted in the push piston 41. Is screwed on. The push stem 42 has a hollow cylindrical shape, and a push housing 43 as an extruding cylinder is attached to the lower end of the push stem 42. This push housing 43
A push-out piston 43a is slidably accommodated therein, and a push rod 45 as a push-out member is urged in a pull-in direction by a spring 44 formed at one end of the push-out piston 43a.
Is provided. Then, the inside of the push cylinder 40 and the inside of the push housing 43 are communicated with each other through a conduit 42a as a communication hole formed through the push stem 42,
The push piston 41 and the push lot 45 are designed to work together. Further, the passage B communicates with the upper chamber 46 through a small hole 48a formed in the peripheral wall of the push cylinder 40 and further through a small hole 41a of the push piston 41 narrower than the small hole 48a. When there is no air connection, that is, when the driving air is not supplied to the passage B, the push piston 41 is biased upward by the compression spring 47 and is located at the top dead center in the push cylinder 40. The push lot 45 is retracted by the biasing force of the spring 44. The push lot 45 is configured to be capable of projecting and retracting from the radial direction on the nail driving axis in the injection hole 6a through the notch groove 6b formed in the nose 6 in the axial direction. On the other hand, when the air connection is established, the passage B is passed through the trigger valve 2020.
Drive air is supplied to the push stem 40, and passes through the first outer peripheral chamber 40a of the push cylinder 40, the small hole 48a, and the conduit in the push stem 42.
It flows into the push housing 43 through 42a, and the air pressure thereof causes the push lot 45 to project from the radial direction onto the nail driving axis in the injection hole 6a of the nose 6 through the pushing piston 43a. Then, with the air supplied to the push piston upper chamber 46 through the small hole 41a, the push piston
When 41 moves down to the position of small hole 48b, small hole 4
Air from 8b is added to lower the push piston 41. By the lowering operation of the push piston 41, the push lot 45 pushes the head of the nail N supplied into the injection hole 6a and disengages the nail from the connected state, whereby the vertical guides 50 and 51 are released.
The nail N is made to project from the tip end of the above for a predetermined length and stopped. In this case, the head of the nail N is pressed by the push lot 45. Since the small hole 48a is formed to have a larger diameter than the small hole 41a, a large amount of driving air is supplied from the push piston upper chamber 46 to the conduit 42a in the push stem 42, Since the air is supplied into the push housing 43, the push lot 45 is projected from the radial direction onto the nail driving axis in the nose 6 faster than the push piston 41 descends.

As described above, by projecting the tip of the nail N from the vertical guides 50, 51 of a predetermined length, the nail N can position the members to be driven. Further, since the nail N can be directly inserted into the nail driving hole, the nail hole can be aimed accurately. Further, since the nail is driven while being inserted into the nail hole, the nail is not displaced with respect to the nail hole.

Then, the inside of the push cylinder 40 and the push housing 43
Since the interior is communicated with via the conduit 42a of the push stem 42, the drive air supplied into the push cylinder 40 to operate the push piston 41 is supplied into the push housing 43 via the conduit 42a. Since the push lot 45 is projected radially from the nail driving axis by the air pressure, the push lot 45 is in the projected state unless the air in the push housing 43 is exhausted.
Therefore, after the supply of the nail N by the push lot 45, until the nail N is struck by the hammer driver 5, the nail N is struck.
Of the nail N can be held so as to project from the head of the nail N, and the tip of the nail N contacts the mating member when searching for the nail hole of the mating member for nailing. Nose 6
Since it is not pushed in, the nailing position can be more reliably aligned.

The vertical guides 50 and 51 have pins 52 and 52 as shown in FIG. 4 (a).
It is attached to the tip of the nose 6 so that it can be opened outward with respect to the center, and is biased in the closing direction by a torsion coil spring 53 shown in FIG. Further, a vertical guide retainer 49 as a holding means is provided on the nose 6 side of the push housing 43, and the vertical guide retainer 49 serves as a chuck mechanism as the push piston 41 descends.
Since the vertical guides 50 and 51 are prevented from rotating in the opening direction by entering the closing position of the 50 and 51, the nail N is restricted from moving in the orthogonal direction and can be firmly held. it can. Thereby, the members to be driven can be accurately positioned.

The push lot 45 has a function of protruding into the nose 6 to push down and hold the nail N when the trigger lever 28 is off, and a vertical guide hold 49 has a function of firmly holding the nail N. And push lot 45 and vertical guide retainer 49
When the trigger lever 28 is turned on, the push rod 45 and the vertical guides 50, 51 are lowered by lowering the impact driver 5 unless the impact driver 5 is retracted from inside the nose 6 and the holding of the vertical guides 50, 51 is not released before lowering. Therefore, in this embodiment, as shown in FIG. 3, a timing valve 60 as a control mechanism is integrally provided around the striking cylinder 3 in order to damage the cylinder. That is, when the trigger lever 28 is pulled,
First, the air in the push cylinder 40 is exhausted from the passage B through the trigger valve 20, and along with this, the push piston
Since 41 is moved upward by the compression spring 47, and the air in the push housing 43 is also exhausted through the conduit 42a of the push stem 42, the push lot 45 is pulled in from the inside of the nose 6 by the spring 44. The outer peripheral chamber 65 of the timing valve 60 communicating with the second outer peripheral chamber 40b of the push cylinder 40 through the communication passage 62 becomes atmospheric pressure, but the lower chamber 63 of the timing valve 60 has the outer peripheral chamber 65 and the small hole 66. As a result, the air in the lower chamber 63 is gradually discharged, so that the timing valve stem 64 descends later than the operation of the push lot 45. This lowering of the stem 64 connects the upper chamber of the head valve 9 to the passage A, and the air in the upper chamber of the head valve 9 passes through the trigger valve 20 and is exhausted. Then, the head valve piston 11 is moved upward, whereby the driving air in the main air chamber 8 is introduced into the striking cylinder 4 and the striking piston 4 moves downward to drive the nail.

By providing the timing valve 60 as described above, the pushlot 45 and the vertical guide retainer 49 are released before the impact driver 5 is lowered, so that the pushlot 45 and the vertical guides 50, 51 are prevented from being damaged by the impact driver 5. can do.

As shown in FIG. 1, the striking driver 5 is made of metal and has a small diameter shaft 5a, a plastic cylindrical body 5b fitted to the outer peripheral side of the shaft 5a, and a cylindrical body 5b. It is composed of a metallic nut 5c for screwing onto the shaft 5a.
As a material of the shaft 5a, a metal having a high toughness, a high tenacity and a high tensile strength, such as iron, is selected. Further, as the material of the cylindrical body 5b, a material that is rich in moisturizing activity and has a small linear expansion coefficient, such as PA, POM, or engineering plastic, is selected. As a result, the impact driver 5 can be reduced in weight, the driving force, the recoil and the durability are equal to those of a normal solid metal driver, and the cost can be significantly reduced as compared with a driver having a half-moon-shaped cross section. .

70 is a contact arm, and this contact arm 70
Is mechanically linked with the trigger lever 28 and has a nose 6
It is installed so that it can be reciprocated in the axial direction of, and is always urged so as to protrude from the tip of the vertical guides 50, 51. By pressing the tip against the driven member, the trigger lever It functions as a kind of safety device that allows 28 pulling operations.

On the side of the nose 6 for the striking driver 5 to eject the nail N, nails as nail supply means for supplying the connecting nails stored in the magazine one by one through the opening 100 into the injection hole 6a. A feeding mechanism 80 is provided. As shown in FIG. 5 (a), the nail feeding mechanism 80 is provided with a feed piston 82 which is movable in a feed piston cylinder 81. The feed piston 82 is always leftward by springs 83 and 84. Being energized. Reference numeral 85 denotes a spring guide for guiding the springs 83 and 84, which is attached to the spring collar 86. 87 is a feed pawl attached to the feed piston 82, and is for feeding the nail N into the injection hole 6a.
90 is a magazine for storing connecting nails. Further, the front chamber 88 of the feed piston cylinder 81 communicates with the return air chamber 18 through a communication passage 89.

Since the nail feeding mechanism 80 is configured as described above, the following operation is performed. In the normal state shown in FIG. 5 (a) (when the striking piston 4 is on the top dead center side), the inside of the return air chamber 18 is communicated with the atmosphere through the communication hole 6c formed in the nose 6, and Thus, the front chamber 88 of the feed piston cylinder 81 communicating with the return air chamber 18 is at atmospheric pressure. Therefore, the feed piston 82 is in the front position by the biasing force of the springs 83 and 84.
In this state, the feed claw 87 pushes the shaft of the second nail to move the leading nail into the nose 6. Thereafter, while the striking piston 4 is driven to reach the bottom dead center side or after that, a part of the compressed air flowing into the return air chamber 18 is transferred to the feed piston cylinder 81 as shown in FIG. Introduced into the front chamber 88. As a result, the feed piston 82 retracts rearward against the biasing force of the springs 83, 84,
The feed pawl 87 engages with the shaft of the next nail. Further, after the striking piston 4 has returned to the ascending position, the inside of the return air chamber 18 becomes the atmospheric pressure again, so that the front chamber 88 of the feed piston cylinder 81 also becomes the atmospheric pressure, and the springs 83 and 84 are attached as in the normal state. The leading nail is sent into the injection hole 6a in the nose 6 by the power.

By the way, in order to describe a series of operations of the nailing machine main body 1 in the present embodiment, in the initial state in which the nailing machine main body 1 is connected to an air supply source (not shown) such as a compressor,
Driving air is introduced from the air supply source into the main air chamber 8 as shown in FIGS. 2, 2 and 6, and the driving air passes through the trigger valve 20 and the door valve 30 and passes through the passage.
It is supplied to both A and B. This passage A leads to the timing valve 60. Further, the air in the passage B moves the push piston 41 and the push lot 45 in the protruding direction, as shown in FIG. Where push piston 41
A part of the air descending is supplied to the lower chamber 63 of the timing valve 60 via the communication passage 62. This air causes the timing valve stem 63 of the timing valve 60 to be positioned above. This timing valve stem
At the position 63, the air from the main air chamber 8 is supplied to the upper chamber 9a of the head valve 9 to close the main valve 9. That is, the head valve piston 11 is joined to the upper end of the striking piston 4.

Next, when the trigger lever 28 is pulled up, the trigger valve stem 25 moves to the housing 21 as shown in FIG.
The pilot valve 23 descends as soon as
27 and the passages A and B are in communication with each other and open to the atmosphere.
As a result, the air in the push piston upper chamber 46 is forced to flow through the small holes 41a,
The gas is exhausted from the passage 27 of the trigger valve 20 through the small hole 48a and the passage B. As a result, the push piston 41
The push lot 45 is retracted to the upper position and the retracted position by the urging force of the springs 47 and 44, respectively. Further, the timing valve 60 communicating with the outer peripheral chamber 40a of the push cylinder 40 through the communication passage 62 has its outer peripheral chamber 65 at atmospheric pressure, but the lower chamber 63 of the timing valve 60 communicates with the outer peripheral chamber 65 and the small hole 66. As the air inside the lower chamber 63 is gradually exhausted through the small holes 66, the timing valve stem 64 descends after the operation of the push lot 45. That is, the timing valve stem 64 is stopped at that position until the inside of the lower chamber 63 reaches a predetermined pressure. Thus, the push piston 41 has a kind of timer function for delaying the time until it is returned to the top dead center. During this time, the air in the main air chamber 8 is supplied to the upper chamber 9a of the head valve 9 via the timing valve 60 to hold the head valve 9 in the closed position.

Further, when the air pressure in the lower chamber 63 of the timing valve 60 drops sufficiently, as shown in FIG.
64 is operated downward by the urging force of the spring 67. By operating this timing valve stem 64, the head valve 9
The upper chamber 9a is connected to the passage A, and the air in the upper chamber 9a is exhausted through the trigger valve 20. Then, the head valve 9 is moved upward by receiving the air pressure in the main air chamber 8, whereby the driving air in the main air chamber 8 is introduced into the striking cylinder 3 and the striking piston 4 moves downward. The nails are prepared. Then, during the downward movement of the striking piston 4, part of the pressure air enters the return air chamber 18 formed around the striking cylinder 3 and accumulates this pressure air. Here, a part of the air accumulated in the return air chamber 18 is part of the nail feeding mechanism 80 described above.
Is introduced into the feed piston cylinder 81, and the feed piston 82 is actuated in the return direction to wait for the feed pawl 87 to engage with the shaft portion of the next nail.

Next, when the trigger valve stem 25 of the trigger valve 20 is opened, air is supplied to the passages A and B as in the above-mentioned initial state. Then, as shown in FIG. 8, the air supplied to the passage A is introduced into the upper chamber 9a of the head valve 9 via the timing valve 60 to move the head valve 9 downward (close it). Then, the engagement between the inner peripheral wall of the head valve piston 11 and the overhanging portion 15a of the piston stop 15 is released,
When the upper part of the striking piston 4 is opened to the atmosphere, the air accumulated in the return air chamber 18 acts on the lower surface of the striking piston 4 to return the striking piston 4 to the top dead center. On the other hand, the air supplied from the passage B is introduced above the push piston 41, and this air is supplied into the push housing 43 through the conduit 42 a of the push piston 41 and the push stem 42 and is supplied to the push piston 43.
The pushlot 45 is actuated in the protruding direction via a.
At this time, since air enters the upper chamber 46 of the push piston 41 through the small hole 41a, the pressure is not sufficiently high, and there is a pressure to push the push piston 41 against the urging force of the compression spring 47. Absent.

Then, as the air pressure in the upper chamber 46 of the push piston 41 becomes sufficiently high, the push piston 41 moves downward as shown in FIG. 9, and the nail supplied to the injection hole 6a of the nose 6 is removed from the connecting member. The nail N is held in a state where it is dissociated and the tip of the nail N is projected for a predetermined length. Further, when the push piston 41 moves downward, the air introduced into the outer peripheral chamber 40b of the push 40 is supplied to the lower chamber 63 of the timing valve 60 through the communication passage 62, and the timing valve stem 64 is operated upward.
By the operation of the timing valve 60, the air supplied to the head valve 9 is switched from the passage A to the main air chamber 8. The above operation is instantaneously executed to perform the nail driving operation.

Next, the operating state of the door valve 30 will be described. First, with the opening / closing door 34 opened for loading nails,
As shown in Fig. 10 (a), the door valve stem 33 is replaced by the spring 32.
The passage B is opened to the atmosphere by being operated downward by. Then, the upper chamber 46 of the push piston 41 becomes the atmospheric pressure, so that the push piston 41 and the push lot 45 are brought into the retracted state by the action of the springs as described above. Therefore, by connecting the second outer peripheral chamber 40b of the push cylinder 40 to the atmosphere, the timing valve stem 64 of the timing valve 60 moves downward. The air supplied to the head valve 9 is switched from the main air chamber 8 to the passage A by the operation of the timing valve 60, but this does not affect the operation of the head valve 9. Then, when the opening / closing door 34 is closed after loading the nails, FIG.
As shown in, the door valve 30 returns to the initial state and the passage A,
Introduce air to B. Further, the push piston 41 and the push lot 45 operate to the initial position by the same operation as when the trigger valve 20 is opened, and the loaded leading nail is moved to the nose 6
Hold at the tip of the extrusion. In this case, the timing valve
60 also operates in the same way as when trigger valve 20 is opened.

That is, first, when the opening / closing door 34 is opened for loading nails, the door valve stem 33 is moved downward by the spring 32, whereby the passage B is opened to the atmosphere and the air in the upper chamber of the push piston 41 is released to the atmosphere. Exhaust. Then the push piston
41 moves upward and push lot 45 retracts.
At this time, the timing valve stem of the timing valve 60 64
Moves downward, but since the air passage of the trigger valve 20 is not open and air is supplied to the passage A, the head valve 9 does not operate. Although the air passage from the main air chamber 8 to the head valve 9 is closed, the door valve stem 33 has moved downward, so that the trigger valve 20 communicates with the main air chamber 8 to prevent air leakage. The outburst of is gone. When the nail N is loaded into the nose 6 in this state and the opening / closing door 34 is closed, the door valve stem 33 moves upward and air is supplied from the trigger valve 20 to the upper chamber 46 of the push piston 40.
At this time, as described above, the air passes through the conduit 42a in the push stem 42 to cause the push lot 45 to project radially from the nail driving axis in the nose 6, and then the push piston
41 is lowered and the nail N is projected from the tip of the vertical guides 50 and 51. At about the same time, the timing valve stem 64 moves upward and the nail is ready to be driven.

Therefore, when the nail is loaded with the nailing machine body 1 connected to the air supply source, the bottom dead center of the push piston 41, the push lot 45, is projected from the radial direction on the nail driving axis in the nose 6, If a nail is supplied into the nose 6 in this state, the first one is not held by the vertical guides 50 and 51, so that it must be run dry. However, as in the present embodiment, the door valve whose command is the opening / closing door 34 is used. By providing 30 and controlling the operation of the push piston 41 and the push lot 45 based on the loading of the nail, it is possible to prepare from the first one to the injection port when loading the nail.
In FIGS. 10A and 10B, 75 is a nail guide member formed integrally with the nose 6, and 76 is a nail connecting band made of plastic or the like.

By the way, in the above-described embodiment, the chuck mechanism for projecting and holding the nail from the tip portion of the nose 6 by a predetermined length is configured to fix the vertical guide to the closed position according to the downward movement of the push piston. However, the present invention is not limited to the above-mentioned embodiment, and for example, the vertical guides may be connected by a spring or the like to urge them in the closing direction. In short, it suffices to have a configuration capable of holding the protruding nail.

(Effect of the Invention) As described above, according to the present invention, since the inside of the WP push cylinder and the inside of the extrusion cylinder are communicated via the communication hole formed through the piston rod, The air supplied into the push cylinder to operate the piston is supplied into the extrusion cylinder through the communication hole, and the air pressure causes the extrusion member to project radially from the nail driving axis. Therefore, as long as the air in the pushing cylinder is not exhausted, the pushing member will be in a protruding state, so that the pushing member engages the head of the nail until after the nail is supplied by the striking driver until just before the nail is hit by the striking driver. The tip of the nail can be held so as to project, and the tip of the nail will not be pushed into the nose even if it comes into contact with the mating member when searching for the nail hole of the mating member for nailing. Therefore, the nailing position can be surely aligned, and since the nailing is performed while the nail is inserted in the nail hole, the displacement between the nail and the nail hole can be prevented, the workability is improved, and the driving accuracy is high. Has the effect of becoming.

Furthermore, since the nail is moved to the tip of the nose by the cylinder mechanism, it is possible to reliably dissociate and move even a connected nail that is firmly connected by a metal wire or a plastic material.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a pneumatic nailing machine according to the present invention, FIG. 2 is a longitudinal sectional view of a trigger valve and a door valve in the embodiment, and FIG. 3 is an embodiment thereof. 4 is a vertical sectional view showing a communication state between the push cylinder and each valve, FIGS. 4 (a) and 4 (b) are partial sectional views showing a chuck mechanism in the same embodiment, a plan view, and FIGS. b)
Is a longitudinal sectional view showing the nail feeding mechanism in the embodiment,
FIG. 7, FIG. 8, FIG. 8 and FIG. 9 are vertical sectional views showing the operation of each valve of the same embodiment, and FIGS. 10 (a) and 10 (b) are vertical sectional views showing the operation of the door valve in the same embodiment. It is a side view. Explanation of symbols 1 ... Nail driver main body, 3 ... Impact cylinder 4 ... Impact piston, 5 ... Impact driver 5a ... Shaft, 5b ... Cylindrical body 6 ... Nose, 6a ... Injection hole 8 ... Main air chamber 9 ... Head valve, 20 ... Trigger valve 27 ... Passage (exhaust hole), 28 ... Trigger lever 30 ... Door valve 33 ... Door valve stem 40 ... Push cylinder 41 ... Push piston 42 ... … Push stem (piston rod) 42a …… Pipe line (communication hole) 43 …… Push housing (extrusion cylinder) 43a …… Extrusion piston 45 …… Push lot (extrusion member) 49 …… Vertical guide retainer (holding means) 50 , 51 …… Vertical guide (chuck mechanism) 60 …… Timing valve (control mechanism) 62 …… Communication passage, 66 …… Small hole 70 …… Contact arm 80 …… Nail feed mechanism (Nail supply means) 87 …… Feed Nail, 100 ... opening

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideki Okushima 6-6 Nihonbashi Hakozakicho, Chuo-ku, Tokyo Max Co., Ltd. (72) Inventor Michiaki Adachi 6-6 Nihonbashi Hakozaki-cho, Chuo-ku, Tokyo Max Co., Ltd. (72) Inventor Koichi Tsukakoshi 6-6 Nihonbashi Hakozakicho, Chuo-ku, Tokyo Max Co., Ltd. (72) Inventor Koji Tanaka 6-6 Nihonbashi Hakozaki-cho, Chuo-ku, Tokyo Max Co., Ltd. (56) Bibliography Shou 48-107174 (JP, U) JP 56-20153 (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. A striking driver for reciprocating an injection hole in a nose provided on a main body of a nailing machine to eject a nail supplied into the injection hole from a tip portion of the nose, and a striking piston integrally connecting the driver. And a striking cylinder in which the striking piston is slidably tightly fitted, a main air chamber connected to an air pressure source, and a piston upper chamber of the striking cylinder and the main air chamber or an exhaust hole. A head valve for switching operation, a trigger valve for sending an operation signal to the head valve, and a nail supply for continuously supplying nails connected to each other into the injection hole through an opening formed on a side surface of the nose. And a cylinder mechanism for disengaging the nail supplied into the injection hole from the connected state and moving the nail toward the tip of the nose. And a push cylinder that operates along a nail driving axis in the nose, a push cylinder that slidably accommodates the push piston, and an extruding cylinder formed at a tip end portion of a piston rod of the push piston. The push cylinder is formed at one end of a push piston slidably accommodated in the push cylinder, and includes a push member that can be projected and retracted radially from the nail driving axis in the nose. The inside is communicated through a communication hole formed through the piston rod so that the push piston and the pushing member operate in an interlocking manner, and the pushing member is moved to the tip of the nose. And a chuck mechanism for holding the fixed nail so that the tip of the nail protrudes. Hammering machine.