JPH0630377Y2 - Nail ejector of nail driver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention is designed to project a part of the nail supplied into the nail injection hole of the nose from the tip of a nail chuck provided at the tip of the nose before driving the nail. The present invention relates to a nail projecting device of a nail driver equipped with a pulling device.

<Prior Art> As shown in Japanese Utility Model Laid-Open No. 64-71076, a pneumatic type is conventionally driven by compressed air to keep the tip of the nail protruding from the nail chuck at the tip of the nose before nailing. The nailing machine has a nail striking mechanism, a nail projecting device, and a control mechanism that pneumatically controls the sequence of these operations.

The nail striking mechanism is a striking cylinder, a striking piston disposed in the striking cylinder, a nose having a nail ejection hole that projects from one end of the striking cylinder coaxially with the striking cylinder and extends coaxially with the striking cylinder. And a driver that is integrally connected to the striking piston as a piston rod and reciprocates in the nail injection hole to slam the head of the nail in the forward nail striking stroke.

The nail projecting device includes a nail push cylinder installed inside the nailing machine main body in parallel with the striking cylinder, a nail push piston arranged reciprocally in the nail push cylinder with a constant stroke, and a nail push piston. A nail pusher connecting rod integrally connected as a piston rod and a fixed stroke reciprocating movement along the nose, and in the forward nail pushing stroke, it was previously supplied into the nail injection hole of the nose by the nail feeding device. A nail pusher that abuts on the head of the nail at the leading position of the connecting nail and separates the nail from the other portion of the connecting nail and pushes it toward the tip of the nose, and is provided at the tip of the nose. A nail chuck fixedly holds a part of the nail body in a protruding state that can be visually recognized by an operator from the tip surface.

The control mechanism is connected to the trigger lever manually operated by an operator, the trigger valve operated by the trigger lever, and the trigger valve, and is provided between the main air chamber and the impact cylinder upper chamber in the nail driving machine main body and the impact cylinder. Connected to the head valve that opens and closes between the cylinder upper chamber and the atmosphere, and the trigger valve, and after the return stroke of the nail projecting device is completed,
An air timer that sets the timing such that the head valve opens after a period of time and the driver's nailing stroke begins.

<Problems to be Solved by the Invention> According to the nail projecting device disclosed in Japanese Utility Model Laid-Open No. 64-7107, since the nail pushing stroke of the nail push piston is constant, when the length of the nail to be used is different. However, the length of the nail protruding from the tip surface of the nail chuck is not constant, which causes a problem in the nail driving operation. For example, in the case of a connecting nail composed of short nails, the tip of each nail may not project from the tip of the nail chuck, and the protruding length of each nail is insufficient to bond a plurality of materials to be fixed. It may not be possible to insert the tip of each nail into the nail hole of the binding metal fitting.

On the other hand, in the case of a connecting nail composed of long nails, the tip surface of the nail chuck cannot contact the surface of the fixed material, so the contact member as a safety device does not rise with respect to the nose, and the trigger Since the lever cannot be pulled, the trigger valve also does not issue the nailing command air pressure signal. Even with a tool that does not have such a contact member, in the case of connecting nails of short nails and connecting nails of long nails, the protruding length of the nails, that is, from the surface of the fixed material to the tip of the nail chuck Due to the different distances, the impact force of the driver applied to the heads of the two types of nails is different, which makes it impossible to make the nail driving depth constant.

Therefore, an object of the present invention is to change the bottom dead center position of the nail pushing stroke of the nail push piston so as to make the nail protruding length from the nail chuck tip constant in a nailing machine using nails of different lengths. It is an object of the present invention to provide a nail projecting device for a nailing machine.

<Means for Solving the Problems> The present invention is capable of reciprocating in the axial direction of the nail chuck provided at the tip of the nose and the nail injection hole of the nose, and at the bottom dead center of the nail injection hole. A nail pusher that abuts the head of the nail and projects the tip of the nail and a part of the nail barrel from the tip of the nail chuck, and the nail pusher interlocks with the nail pusher in the axial direction of the nail injection hole, and nails in the axial direction of the nail injection hole. The nail push piston that reciprocates the pusher, the nail push cylinder that incorporates the nail push piston and extends almost parallel to the axis of the nail injection hole, and the nail push piston that is arranged in the lower end of the nail push cylinder and its bottom dead center A nailing machine having a nail push piston stop for stopping contact with the nail push piston stop, wherein an annular handle portion is integrally formed at a lower end portion through a plurality of locking portions extending in a radial direction. An adjuster is provided, and an opening formed of a guide portion extending in the axial direction and a plurality of circumferential locking grooves continuous with the guide portion is formed on a peripheral wall of an adjuster guide provided below the nail push cylinder and extending in the axial direction. However, by selectively engaging the engaging portion of the adjuster with the engaging groove of the adjuster guide, the position of the piston stop can be set at at least two different positions in the axial direction of the nail push cylinder. It is a feature.

<Operation> By setting the stop position of the nail push piston stop according to the length of the nail to be used, the nail push piston stop is stopped at at least two different positions in the axial direction,
Since the bottom dead center position of the nail push piston is changed, the bottom dead center position of the nail pusher with respect to the axial direction of the nail injection hole is changed, and the position of the head of the nail with which the nail pusher abuts is changed. Therefore, even when several kinds of connecting nails having different nail lengths are used, the protruding length of the nail from the tip of the nail chuck is kept constant. Therefore, the distance between the tip of the nail chuck and the surface of the fixed material is constant regardless of the nail length, the impact force of the driver is constant, and the nail driving depth is constant.

<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a main part of a pneumatic nailing machine equipped with a nail projecting device of the present invention, showing a state in which a striking piston is stationary at top dead center.

As shown in FIG. 1, a striking cylinder 2 is arranged inside the nailing machine body 1, and a striking piston 3 is reciprocally arranged inside the striking cylinder 2. At the lower end of the nailing machine body 1, there is provided a nose 5 having a nail injection hole 4 which projects from one end of the striking cylinder 2 coaxially with the striking cylinder 2 and extends coaxially with the striking cylinder 2. On the lower surface side of the striking piston 3, a driver 6 that strikes the head of the nail as a piston rod is integrally connected to the striking piston 3. The driver 6 reciprocates in the nail injection hole 4 of the nose 5.

In the striking cylinder 2, compressed air for reciprocating the striking piston 3 is supplied inside the nailing machine body 1 from a main air chamber 7 formed around the striking cylinder 2. The main air chamber 7 is connected to a compressed air source (not shown) existing outside the nail driver, and the compressed air is replenished from the compressed air source.

An annular head valve 8 is arranged on the outer circumference of the upper end of the striking cylinder 2. Head valve 8
Is an upper head valve cylinder element 10 constituted by a part of the cap 9 of the nailing machine body 1 and the cap 9
In a substantially annular head valve bore 12 formed by upper and lower head valve cylinder elements 10 and 11 interposed between and fixed to the impact cylinder 2. A head valve body 13 arranged so as to reciprocate in the axial direction of the striking cylinder 2 and an upper head valve cylinder element 1
0 and a valve spring 12a arranged inside. In the cap 9 of the nailing machine body 1, a piston stop 1 made of an elastic material is provided at a portion facing the upper end surface of the striking cylinder 2.
4 is fixed. The striking piston stop 14 holds the striking piston 3 in a state of preventing the rebound of the striking piston 3 when the striking piston 3 returns to the top dead center.

The head valve body 13 has a main opening / closing valve portion 15 which opens and closes between the main air chamber 7 and the striking piston upper chamber 2a of the striking cylinder 2 at the lower part thereof, and the striking piston upper chamber 2a and the atmosphere inside the middle portion. Has an annular exhaust valve portion 16 that opens and closes between, and an annular control portion 18 that receives a nailing command air pressure signal and a nailing end air pressure signal from the trigger valve 17 on the outside of the intermediate portion, and has an upper portion on the upper side. A head valve body 1 is slidably engaged with the head valve cylinder element 10.
It has a guide portion 19 in the form of a short cylinder that guides the axial movement of 3.

A plurality of slits 20 are provided at the lower end of the main opening / closing valve section 15 so as to be distributed in the circumferential direction of the main opening / closing valve section 15. Further, a plurality of grooves 21 are provided on the upper surface of the exhaust valve portion 16 so as to be dispersed in the circumferential direction of the exhaust valve portion 16.

When the head valve body 13 is stationary at the bottom dead center, the inner peripheral wall of the main opening / closing valve portion 15 is fitted to the lower end outer peripheral surface of the lower head valve cylinder element 11 at a position above the slit 20. It contacts the ring 22 and closes between the main air chamber 7 and the striking piston upper chamber 2a. Further, the exhaust valve portion 16 has O
The striking piston upper chamber 2a is opened to the atmosphere by coming into contact with the O-ring 23 fitted above the ring 22 and on the outer peripheral surface of the lower head valve cylinder element 11.

On the other hand, when the head valve body 13 is stationary at the top dead center, the inner peripheral wall of the main opening / closing valve portion comes into contact with the O-ring 22 at the portion having the slit 20, and the main air chamber 7 and the striking piston upper chamber 2a. Open up between and. Further, the exhaust valve portion 16 comes into contact with the O-ring 23 at a position lower than the groove 21 and closes between the striking piston upper chamber 2a and the atmosphere.

A large number of small holes 24 are distributed in the circumferential direction of the striking cylinder 2 in the axial direction of the circumferential wall of the striking cylinder 2, approximately in the middle.
Is provided. These small holes 24 communicate with a return air chamber 26 formed on the outer periphery of the lower portion of the striking cylinder 2 via a check valve 25 such as a rubber band fitted to the outer surface of the striking cylinder 2. . Striking cylinder 2
A communication hole 2c that constantly connects the return air chamber 26 and the striking piston lower chamber 2b is provided on the peripheral wall of the lower portion of the above.

A trigger valve 17 for issuing a nailing command air pressure signal and a nailing end air pressure signal is provided at the base end portion (the left end of the grip portion 27 in FIG. 1) of the grip portion 27 of the nailing machine body 1. A trigger 28 is provided on the lower outer surface of the nailing machine body 1 so as to face the trigger valve 17.

The trigger valve 17 is inserted into a hole 27a formed in the base end portion of the grip portion 27, and is fixed to a cap 30 fitted in a lower end opening of a substantially cylindrical trigger valve housing 29, and a trigger. A substantially cylindrical trigger valve piston 31 slidably arranged in a chamber formed by the valve housing 29 and the cap 30, and a chamber formed by the cap 30 and the trigger valve piston 31 , A trigger valve stem 32 whose lower end projects toward the trigger 28.

A plurality of communication holes 33 are provided in an approximately middle portion of the peripheral wall of the trigger valve housing 29 so as to be distributed in the circumferential direction of the trigger valve housing 29. The communication hole 33 is
It is connected to an air passage 34 extending through the lower portion of the nailing machine body 1 and the nose 5. The air passage 34 is shown in FIG.
As shown in FIG. 6, it is connected to the inside of the lock cylinder 105 of the nail holder lock piston / cylinder mechanism 101 of the nail chuck 35.

The communication hole 33 extends into the upper portion of the nailing machine body 1 and finally the upper head valve cylinder element 1 of the head valve 8.
It is connected to an air passage 38 which is connected to a control chamber 40 formed in the zero. The air passage 38 is connected to the control chamber 40 via a check valve 41, a timing valve 42, and an air passage 39 provided at the upper end of the front of the nailing machine body 1.

Between the cap 30 and the trigger valve housing 29, there is always provided an exhaust passage 43 open to the atmosphere.

The trigger valve piston 31 is located above and below the communication hole 33 in the intake valve portion 31a and the exhaust valve portion 31 respectively.
b. The air supply valve portion 31a has an O-ring 44 on its outer peripheral surface, and the O-ring 44 opens and closes between the main air chamber 7 and the inside of the trigger valve housing 29. The exhaust valve portion 31b has an O-ring 45 on its outer circumference, and opens and closes the inside of the trigger valve housing 29 (that is, the communication hole 33) and the exhaust passage 43. When the trigger valve piston 31 is stationary at the top dead center, the O-ring 44 is separated from the hole wall surface of the trigger valve housing 29 and allows the main air chamber 7 and the communication hole 33 to communicate with each other. At this time, the O-ring 45 is in close contact with the hole wall surface of the trigger valve housing 29, and the communication hole 33 is formed.
The exhaust passage 43 is closed. On the other hand, when the trigger valve piston 31 is stationary at the bottom dead center, the O-ring 44 closes between the main air chamber 7 and the communication hole 33. At this time, the O-ring 45 separates from the wall surface of the hole of the trigger valve housing 29 and opens the communication hole 33 to the atmosphere via the exhaust passage 43.

A communication hole 46 that always communicates between the main air chamber 7 and the inside of the trigger valve piston 31 is provided in the central shaft portion of the air supply valve portion 31a. A return spring 47 for urging the trigger valve stem 32 toward the trigger 28 is provided inside the trigger valve piston 31.

In the trigger valve stem 32, O-rings 49 and 50 are fitted in a portion that slides on the wall surface of the hole 48 provided in the cap 30. As shown in FIG. 1, when the trigger valve stem 32 is stationary at the bottom dead center, the O-rings 49 and 50 are brought into close contact with the wall surface of the hole 48, and the trigger valve stem 32 and the cap 30. Close the gap (not shown) with the trigger valve piston 31
When the inside of the valve is cut off from the atmosphere and is pushed up to the top dead center by the trigger lever 51 of the trigger 28, the O-rings 49 and 50 are separated from the wall surface of the hole 48, and the trigger valve stem 32 and the cap. The gap with 30 is opened, and the inside of the trigger valve piston 31 is opened to the atmosphere. When the main air chamber 7 in the nailer body 1 is connected to the compressed air source, the trigger valve 17 allows the compressed air in the main air chamber 7 to pass below the trigger valve piston 31 via the communication hole 46. Is supplied to the inside of the cap 30 formed in the above, and the trigger valve piston 31 operates so as to stand still at the top dead center by the pressure of the compressed air inside the cap 30. The O-ring 49 is located at a position where the trigger valve stem 32 is moved upward, and the communication hole 46 of the trigger valve piston 31.
To close the communication between the lower chamber of the trigger valve piston 31 and the main air chamber 7.

The trigger 28 is composed of a trigger lever 51 and a trigger lock 52 as a safety device. The trigger lever 51 is pivotally supported by the nailing machine body 1 at one end 51a, and a latch claw 55 is provided on a part of the outer circumference of the one end 51a. The trigger lever 51 has an opening 53 in the vicinity of the one end 51 a, and the trigger lever 5 has a larger opening than the opening 53.
There is a trigger lever stop 54 on the side closer to the free end of 1.

The trigger lock 52 includes a support frame 56 fixed to the nailing machine body 1, a trigger lock lever 58 pivotally supported by the support frame 56 via a pivot shaft 57, and a trigger lock lever 58 which is a counterclockwise watch in FIG. Compression spring 5 that biases in the direction
9, and is supported by the support frame 56 via a pivot 57,
It has an L-shaped trigger latch lever 60 which is separate from the trigger lock lever 58, and a torsion coil spring 61 which biases the trigger latch lever 60 counterclockwise in FIG.

The trigger lock lever 58 has a spring receiving piece 58a at a portion extending below the pivot 57. Compression spring 59
Is interposed between the spring receiving piece 58a and the support frame 56, and always urges the trigger lock lever 58 counterclockwise in FIG. The upper end of the trigger lock lever 58 penetrates through the opening 53 of the trigger lever 51 and is located above the trigger lever 51. At the upper end of the trigger lock lever 58, a trigger lock claw 63 that engages and disengages with the upper surface of the trigger lever 51 in the vicinity of the one end 51a of the trigger lever 51.
Is provided. A trigger lock operating lever 5 provided with a finger hook 58b arranged near the trigger lever 51
8c is rotatably provided on the support frame 56 by a pivot 58d. The trigger lock operation lever 58c is formed with an operation end 58f that engages with a protruding end of a pin 58e supported on the upper end of the trigger lock lever 58. An operator pushes the pin 58e to the right in FIG. 2 through the operation end 58f by rotating the trigger lock operating lever 58c counterclockwise in FIG. 2 to move the trigger locking lever 58 in FIG. Rotate clockwise. Even if only the trigger lever 51 is pulled from the state shown in FIG. 1, the trigger lock claw 63 engages with the upper surface of the trigger lever 51 and locks the trigger lever 51.
The trigger lever 51 cannot be pulled. In order to switch the trigger valve 17 to generate the nailing command air pressure signal, first, the finger hook portion 58b of the trigger lock operating lever 58c is operated, whereby the trigger lock lever 58 is rotated clockwise in FIG. Move the trigger lever 5
1, the trigger lever 51 is pulled, and the trigger valve stem 32 is pushed up to the top dead center. During this time, the latch claw 55 of the trigger valve 51 contacts the upper end surface of the trigger latch lever 60 to rotate the trigger latch lever 60 counterclockwise, and then the torsion coil spring 61.
With the force of, the latch claw 55 and the free end of the trigger latch lever 60 are latched. Therefore, when the trigger valve stem 32 is once pushed up to the top dead center and is returned to the bottom dead center, the operator releases the finger from the finger hook portion 58b of the trigger lock operating lever 58c to release the trigger lock operating lever. 58c is released, whereby the trigger lock lever 58 is rotated counterclockwise by the biasing force of the compression spring 59 to release the latched state of the latch claw and the trigger latch lever 60, and then the finger is released from the trigger lever 51. There must be.

The air passage 38 connected to the communication hole 33 of the trigger valve housing 29 is provided in a magazine 64 for loading connecting nails (not shown), and the nail injection hole 4 of the nose 5 and the magazine 6 are provided.
When a connecting nail is loaded between the nail push piston upper chamber 73a and the nail push piston 73 in the nail push cylinder 73 of the device 71, the air passage 38 is projected by the opening / closing operation of the door (not shown) opened and closed by the operator. Door valve 6 that opens and closes against
5 is connected inside. The door valve 65 is arranged between the upper annular air passage 85 and the air passage 38,
In order to return the nail push piston 67 to the top dead center when the door is opened for the connection nail loading operation or the like, the nail push piston 67 is disconnected from the upper annular air passage 85 and the air passage 38 and is simultaneously connected to the atmosphere. On the other hand, the door valve 65 connects the upper annular air passage 85 to the air passage 38 when the door is closed. When the door is closed before the nailing work (that is, when the compressed air is supplied to the main air chamber 7 but the trigger lever 51 is not pulled), the compressed air pressure supplied through the door valve 65 causes The nail push piston 67 moves the piston rod 68 and the nail pusher 69 in the direction of the bottom dead center, advances the nail pusher 69 into the nail injection hole 4, and is loaded into the nail injection hole 4 of the nose 5 of the connecting nails. The other nail is cut off from the other part of the connecting nail and chucked by the nail chuck 35. During this time, the nail pusher 69 abuts on the nail head in the nail ejection hole 4. Magazine 6
A nail feeding device 70 driven by a nail feeding piston / cylinder mechanism (not shown) is provided between the No. 4 and the nose 5.

The nail projecting device 71 is fitted into the nail projecting device housing 72 and a substantially cylindrical nail projecting device housing 72 that is provided in the front part of the nailing machine body 1 so as to be inclined with respect to the axis of the striking cylinder 2. A nail push cylinder 73
In the nail projecting device housing 72, projecting from a position below the nail push cylinder 73 toward the nose 5, and
A fixed cylindrical adjuster guide 74 and at least two types of connecting nails that are internally mounted in the adjuster guide 74 and that are movable in the axial direction and the circumferential direction with respect to the adjuster guide 74 and have different nail lengths. The nail projecting amount adjuster 75 that adjusts the amount of nail projecting from the nail chuck 35 to any of the connecting nails so that the nail projecting device 71 can cope with it, and the nail installed in the nail push cylinder 73. A push piston 67, a compression spring 67a that returns the nail push piston 67 to the top dead center, a piston rod 68 integrally connected to the nail push piston 67, and a connector 76 that connects the lower end of the piston rod 68 and the nail pusher 69. , The nose 5 is attached to the nose 5 so as to be slidable with respect to the nose 5.
Nail pusher 6 that moves in and out of the nail injection hole 4 of
9 and a nail chuck 35 provided at the tip of the nose 5.

The upper end surface of the nail push cylinder 73 is the nailer body 1
The cap 9 is in contact with the spacer 80 arranged at the position where the timing valve 42 is inserted.
Further, on the outer periphery of the upper end of the nail push cylinder 73, an annular outward flange 84 that is in sealing contact with the inner wall surface of the nail projecting device housing 72 is provided. A short cylindrical bush 77 is provided on the inner circumference of the upper end of the nail push cylinder 73.
a is fitted. A plurality of grooves 77b and 77c penetrating the peripheral wall of the bush 77a are provided at the upper end and the lower end of the bush 77a. The bush 77a includes a small diameter portion 77d having an outer diameter smaller than the inner diameter of the nail push cylinder 73 and the nail push cylinder 73.
Has an outer diameter equal to the inner diameter of the large diameter portion 77f into which the O-ring 77e is fitted.

In the vicinity of the upper end of the nail push cylinder 73, communication holes 77, 78 and 79 are provided in order from top to bottom. At the portion of the nail push cylinder 73 where the communication holes 78 and 79 are provided, annular rubber bands 78a and 7 are provided.
9a is fitted and constitutes a check valve capable of only compressed air outflow from the inside of the nail push cylinder 73 to the outside. The communication holes 77 and 78 are connected to the gap between the small diameter portion 77d of the bush 77a and the nail push cylinder 73, and the communication hole 79 is connected to the inside of the bush 77a via the groove 77 of the bush 77a. A cylindrical outward flange 81 that is in contact with the inner wall surface of the nail projecting device housing 72 in a sealed manner is provided slightly below the intermediate height position of the nail push cylinder 73. At the lower end of the nail push cylinder 73, a cylindrical outward flange 82 that comes into contact with the inner wall surface of the nail projecting device housing 72 is also provided. A plurality of grooves 83 are formed so as to radially penetrate the lower surface of the outward flange 82 and the peripheral wall of the nail push cylinder 73.

As can be understood from the above description, in the nail projecting device housing 72, an upper annular air passage 85 surrounding the upper portion of the nail push cylinder 73 is formed between the outward flanges 84 and 81, and the upper annular air passage 85 is formed. Is
It is connected to the air passage 38 via the door valve 65 described above. On the other hand, a lower annular air passage 86 surrounding the lower portion of the nail push cylinder 73 is connected to the main air chamber 7 between the outward flanges 81 and 82.

The nail push piston 67 has a two-stage piston shape, and has a small diameter piston 87 on the upper side and a large diameter piston 88 on the lower side. As shown in FIG. 1, when the nail push piston 67 is stationary at the top dead center, the small-diameter piston 87 is engaged with the bush 77a and the large-diameter piston 88 is the lower surface of the bush 77a. In position, it engages the nail push cylinder 73.

As shown in FIG. 8, the adjuster guide 74 is provided at its upper portion with an outward flange 74a that comes into contact with and engages with an inward flange 72a provided at the lower end of the nail projecting device housing 72. Also, the adjuster guide 7
The peripheral wall of No. 4 is provided with a substantially U-shaped opening 74b. The opening 74b includes an axial guide portion 74c extending in the axial direction of the adjuster guide 74, a long nail locking groove 74d connected to the upper end of the axial guide portion 74c and extending in the circumferential direction of the adjuster guide 74, and a shaft. It is composed of a short nail locking groove 74e which is connected to the lower end of the direction guiding portion 74c and extends parallel to the long nail locking groove 74d but is displaced in the circumferential direction. The groove lower end surface 74g of the long nail locking groove 74d and the axial guide portion 74c
A rectangular adjuster stop 74f projecting upward with respect to the groove lower end surface 74g is formed at a connection portion with. The short nail locking groove 74e has a groove lower end surface 74h and is connected to a guide opening 74i that extends to the lower end of the adjuster guide 74 in the axial direction of the adjuster guide 74.

On the other hand, the adjuster 75 includes a cylindrical nail push piston stop 75a and the nail push piston stop 75a.
At the lower end of a, a locking portion 75d protruding in the radial direction of the nail push piston stop 75a, and an annular handle portion 75c integrally connected to the nail push piston stop 75a via the locking portion 75b. . Handle 75c
A knurl is engraved on the outer peripheral surface of the.

As can be seen from FIG. 8, when the pneumatic nailing machine uses short nails, the locking portion 75b of the adjuster 75 has the groove lower end surface 74h of the short nail locking groove 74e of the adjuster guide 74.
Engage with. On the other hand, when the pneumatic nailer uses long nails, the locking portion 75b of the adjuster 75 engages with the groove lower end surface 74g of the long nail locking groove 74d.

FIG. 1 shows that when the pneumatic nailer uses short nails, the engaging portion 75b of the adjuster 75 has the engaging groove 74 for short nails.
It shows a state of engaging with the groove lower end surface 74h of e, and the upper end surface 75d of the nail push piston stop 75a of the adjuster 75 is located on the lower side. Although not shown in FIG. 1, when the pneumatic nailer uses long nails, the upper end surface 75 of the nail push piston stop 75a is
It will be located on the higher side of d.

As shown in FIGS. 1 and 32, the connector 7
6 is a nail push piston 67 and a piston rod 6
When 8 moves between the top dead center and the bottom dead center, in order to compensate for the lower end of the piston rod 68 inclined with respect to the axis of the striking cylinder 2 to move away from or close to the nose 5, A bolt 90 with a screw is loosely fitted in a long hole 89 extending substantially in the direction of the horizontal axis with respect to the second axis.

As shown in FIG. 3, the bolt 90 has a nose 5
It is screwed onto a slider 92 which is slidably mounted in an axial groove 91 provided on the outer surface of the. Slider 92
Is held by a slider retainer 94 fixed to the nose 5 by a pin 93 so as not to come off the groove 91.

As shown in FIG. 4, a lever-shaped nail pusher 69 is pivotally supported on the slider 92 via a pivot 95. The tip surface of the free end of the nail pusher 69 forms a nail head contact surface 69a that contacts the upper surface of the nail head. At the pivot end of the nail pusher 69, a nail pusher stop 92a formed on the slider 92 is engaged so that the nail head contact surface 69a overlaps with the upper surface of the nail head in the nail injection hole 4 of the nose 5. As described above, the stop contact surface 69b is formed so as to maintain the posture of the nail pusher 69 (see a portion indicated by a chain double-dashed line in FIG. 4). The nail pusher 69 is
In FIG. 4, in the counterclockwise direction (from the nail injection hole 4 to the nail pusher 69
Is always urged). As shown in FIG. 4, when the slider 92 is stationary at the top dead center, the nail pusher 69 hits the protrusion 97 protruding downward from the upper end of the nose 5 to allow the nail pusher 69 to move from the inside of the nail injection hole 4. It is forcibly evacuated.

As shown in FIGS. 1 and 4 to 6, the nail chuck 35 is rotatable back and forth by a pair of pivot pins 98 provided at the front and rear of the nose 5 at the tip of the nose 5. The nail holders 99 and 100, and the nail holders 99 and 100 and the nail pusher 69 hold the nails coaxially with the axis of the nose 5.
9 and 100 for locking the nail holder locking piston and cylinder mechanism 101.

The pair of nail holders 99 and 100 forms a tapered hole 102 that is continuous with the nail injection hole 4 in the closed state. The inclined wall surface of the tapered hole 102 abuts the side surface of the nail body. Lock operation ends 99a and 100a for engaging and disengaging the piston rods 103 and 104 of the nail holder lock piston / cylinder mechanism 101 are provided at the upper ends of the nail holders 99 and 100, respectively.

The nail holder lock piston / cylinder mechanism 101 is
As shown in FIG. 3, a lock cylinder 105 having a bore 105a extending in a direction perpendicular to the axis of the nose 5 and integrally formed with the nose 5, and a lock cylinder 10
5, a pair of lock pistons 106 and 10
7 and the piston rods 103 and 1 projecting from the lock pistons 106 and 107 toward the locking operation ends 99a and 100a of the nail holders 99 and 100, respectively.
04 and a pair of cylinder caps 1 fixed to the lock cylinder 105 by a step and a snap ring 108.
09. Although not shown in FIGS. 5 and 6, the lock pistons 106 and 107 are not shown.
Has an O-ring. Cylinder cap 109
Has an annular slide guide portion for guiding the movement of the piston rods 103 and 104.

The air passage 34 opens inside the lock cylinder 105 at an intermediate position in the lengthwise direction of the lock cylinder 105, and the air pressure in the air passage 34 is controlled by the rear surface of the front lock piston 106 and the rear lock piston 106. It acts on the front surface of 107. As shown in FIG. 4, the air passage 3
4 is supplied with compressed air, the lock pistons 106 and 107 are advanced to the positions where they abut the front and rear cylinder caps 109, respectively, and the tips of the piston rods 103 and 104 of the nail holders 99 and 100 respectively. It is pressed against the lock operation ends 99a and 100a. This allows the nail holders 99 and 100
Contact each other, and cooperate with the nail pusher 69 to fix the nail coaxially with the nail injection hole 4 with the wall surface of the tapered hole 102 pressed against the head and the body of the nail.

The timing valve 42 is provided above the nail push cylinder 73 in the cap 9 of the nailing machine body 1. The timing valve 42 includes a timing valve cylinder 110 and a timing valve cylinder 11
0, which projects from the lower end and has an axial through hole 112.
And a valve spring 113 for urging the timing valve stem 111 toward the bottom dead center. Timing valve cylinder 1
10 has a communication hole 114 connected to the air passage 38 and a communication hole 115 connected to the air passage 39. The lower end of the timing valve stem 111 engages and disengages with the upper surface of the nail push piston 67 (the upper end surface of the piston rod 68 in the case of FIG. 1). As shown in FIG. 1, when the nail push piston 67 is stationary at the top dead center, the lower end of the timing valve stem 111 abuts the upper surface of the nail push piston 67, and the timing valve stem 111
Has been pushed to top dead center. At this time, the O-ring 116 fitted in the large-diameter portion 117 of the timing valve stem 111 is separated from the inner wall surface of the timing valve cylinder 110, and the communication holes 114 and 115 are connected to each other. 38 and 39 are connected. While the nail push piston 67 is moving from the top dead center to the bottom dead center, the timing valve stem 111 is also moved in the direction from the top dead center to the bottom dead center by the valve spring 13. When the timing valve stem 111 reaches the bottom dead center, the O-ring 116 moves to the timing valve cylinder 11
It is pressed against the wall surface of No. 0 and closes between the communication holes 114 and 115. As a result, the space between the air passages 38 and 39 is closed. In this way, the timing valve stem 111
Is operated by the contact and separation relationship with the nail push piston 67, so that the sequence in which the head valve 8 is opened is secured after the nail push piston 67 reaches the top dead center.

The check valve 41 is arranged in parallel with the timing valve 42 with respect to the air passages 38 and 39. Check valve 4
1 is a bore 12 formed in the cap 9 of the nailing machine body 1.
The check valve cylinder 118 is inserted in the No. 2 and the check valve body 119 having a rubber band shape. Check valve cylinder 118
Has a bottomed cylindrical shape and has a diameter portion 123 having an outer diameter smaller than the diameter of the bore 112. The check valve cylinder 118 is
Communication holes 120 and 121 are provided at upper and lower positions of the peripheral wall. The communication hole 120 is provided in the small diameter portion 123,
It can be connected to the air passage 39 via a check valve body 119 fitted to the outer circumference of the small diameter portion 123. The communication hole 121 is for maintaining the air passage 38 in an open state. Therefore, if the shape of the check valve cylinder is changed as shown in FIG. 7, it becomes unnecessary. The check valve 41 is connected to the air passage 3 in order regardless of opening / closing of the timing valve 42.
8, the communication hole 121, the inside of the check valve cylinder 118, the communication hole 120, and the air passage 39 to form a one-way compressed air passage from the trigger valve 17 to the control chamber 40 of the head valve 8, and conversely the head valve 8 It functions to prevent the formation of the compressed air passage from the control chamber 40 to the trigger valve 17.

Hereinafter, a series of operations of the pneumatic nailer will be described.
First, depending on the length of the nail to be used, the main air chamber 7 in the nailing machine main body 1 in which the adjuster 75 is manually operated to set the nail push piston stop 75a at a predetermined stop position.
Is connected to a compressed air source, a connecting nail is loaded between the magazine 64 and the nail injection hole 4 of the nose 5, and before the nailing operation with the door closed, the trigger valve stem 32 of the trigger valve 17 is It is stationary at the bottom dead center, and the trigger valve piston 31 is stationary at the top dead center by the compressed air pressure introduced into the cap 30. Therefore, the air passage 3
Compressed air in the main air chamber 7 is supplied to 4 and 38. Therefore, the nail in the nail injection hole 4 is separated from the other part of the connecting nail by the movement of the nail push piston 67 to the bottom dead center, and the nail pusher 69 and the nail chuck 35 cause the nail in the axis of the nail injection hole 4 to move. The nail holders 99 and 100 of the nail chuck 35, which are held coaxially, are locked by a nail holder lock piston / cylinder mechanism 101.

The nail push piston 67 comes into contact with the upper end surface 75d of the nail push piston stop 75a, and the nail is held in a state in which the tip thereof protrudes from the nail chuck 35 by a predetermined length.

On the other hand, the timing valve stem 111 of the timing valve 42 is at the bottom dead center, and the space between the communication holes 114 and 115 is closed. Therefore, the air passages 38 and 39 are
Although connected via the check valve 41, compressed air is supplied from the trigger valve 17 to the head valve 8, but compressed air escapes from the head valve 8 to the trigger valve 17. It has been blocked. Therefore, unless the nail push piston 67 returns to the top dead center, even if the trigger lever 51 is pulled, the compressed air does not escape from the control chamber 40 of the head valve 8 and the head valve 8 does not open.

When the trigger lever 51 is pulled from this state, the trigger valve stem 32 moves from the bottom dead center to the top dead center, and the compressed air in the air passages 34 and 38 passes through the exhaust passage 43 of the trigger valve 17 into the atmosphere. Is released. For this reason, the lock action of the lock pistons 106 and 107 of the nail holder lock piston / cylinder mechanism 101 is released, the compressed air in the nail push piston upper chamber in the nail push cylinder 73 is also released into the atmosphere, and the nail push piston 67 is released. ,
After returning from the bottom dead center to the top dead center, the timing valve 111 is pushed up to the top dead center at the top dead center. Therefore, the communication hole 114
And 115 are connected, and the compressed air in the control chamber 40 of the head valve 8 is discharged into the atmosphere through the air passage 39, the communication hole 114, the inside of the timing valve 42, the communication hole 115 and the air passage 38. As a result, the head valve 8
Open, the striking piston 3 descends, and the tip of the driver 6 drives the nail into the driven material.

Then, when the trigger lever 51 is released, the trigger valve stem 32 moves from the top dead center to the bottom dead center, issues a nailing end compressed air pressure signal, and closes the communication hole 33 to the exhaust passage 43. At the same time, it is connected to the main air chamber 7. Therefore, compressed air is supplied to the air passages 34 and 38, and the head valve 8 shuts off the striking piston upper chamber 2a from the main air chamber 7 and at the same time opens it to the atmosphere, so that the striking piston 3 returns to the top dead center. The nail push piston 67 is returned from the top dead center by returning the compressed air in the chamber 26 to the nail push piston stop 7
5a is moved to the bottom dead center set by the upper end surface 75d of the nail 5a, and in the process, the nail pusher 69 moves the leading nail of the connecting nail fed into the nail injection hole 4 of the nose 5 by the nail feeding device 70. Separated from the other parts, and push until the nail body is held by the nail chuck 35. After this, the lock piston 10 of the nail holder lock piston / cylinder mechanism 101
6 and 107 advance to the front and back respectively, and the nail holder 9
Locked 9 and 100. Therefore, the nail is fixedly held by the nail holders 99 and 100 and the nail pusher 69 so as to project from the tip of the nail chuck 35 of a constant length for the next nailing operation.

<Effect of the Invention> According to the present invention, the nail protruding length from the nail chuck tip can be made constant even if the nail length is different. In, the distance between the tip of the nail chuck and the surface of the fixed material is constant, the impact force of the driver is constant, and the nail driving depth is constant.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a pneumatic nailer equipped with a nail ejecting device of the present invention, FIG. 2 is an external side view of the nailer, and FIG. 3 is a III-III line in FIG. Sectional view, FIG.
Fig. 5 is a sectional view taken along line IV-IV in Fig. 5, and Fig. 5 is a sectional view taken along line VV in Fig. 4, showing a state in which the nail chuck is unlocked, and Fig. 6 is the same as Fig. 5. FIG. 7 is a cross-sectional view showing a state in which the nail chuck is locked, and FIG. 7 is an enlarged view of the vicinity of the timing valve in FIG. 1, but a part of the check valve is changed in design. FIG. 8 is an exploded perspective view of the adjuster and the adjuster guide. 4 ... Nail injection hole, 5 ... Nose, 35 ... Nail chuck, 67 ... Nail push piston, 69 ... Nail pusher, 71 ... Nail protrusion device, 73 ... Nail push cylinder, 74 ... Adjuster guide , 75 ... Adjuster, 75a ... Nail push piston stop.

Claims (1)

[Scope of utility model registration request] 1. A nail chuck provided at the tip of the nose,
Reciprocable in the axial direction of the nail injection hole of the nose, and
A nail pusher that abuts the head of the nail in the nail injection hole at the bottom dead center and projects the nail tip and part of the nail barrel from the nail chuck tip, and interlocks with the nail pusher in the axial direction of the nail injection hole. A nail push piston that reciprocates the nail pusher in the axial direction of the nail injection hole, a nail push cylinder that incorporates a nail push piston and extends almost parallel to the axis of the nail injection hole, and a nail that is arranged in the lower end of the nail push cylinder. A nailing machine having a push piston and a nail push piston stop that abuts and stops at its bottom dead center, including a nail push piston stop, and an annular shape through a plurality of locking portions extending in a radial direction at a lower end portion. An adjuster having a handle portion integrally formed is provided, and a guide portion extending in the axial direction and a guide portion extending in the axial direction are provided on a peripheral wall of an adjuster guide provided below the nail push cylinder and extending in the axial direction. An opening formed of a plurality of circumferential engagement grooves continuous with each other, and the engagement portion of the adjuster is selectively engaged with the engagement groove of the adjuster guide, whereby the position of the piston stop is pushed by a nail. At least two different cylinder axial directions
A nail projecting device for a nailing machine, which can be set at any location.