JPS5843234B2 - Nailer bumper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a screwdriver, which is a nailing member that is slidably and tightly fitted into a main cylinder built into a tool body and is integrally connected, as a nailing part that protrudes from the main body. This relates to a bumper device for a nail gun, which is arranged to receive the main piston at the bottom dead center position of the main piston to operate the main piston vigorously within the driver guide hole formed through the nose of the nail gun. be.

As shown in Fig. 1, this type of nailing machine operates by applying fluid pressure such as compressed air pressure to the main piston A to cause the main piston A to rapidly lower in the main cylinder B. Hit the head E' of the nail E that has been preloaded into the driver guide hole V of the nose D with the tip C' of the driver C integrally arranged in the axial direction of the nose D, and drive the nail E from the nose tip D''. It is known that the nails are constructed so that the nailing work can be easily performed by hammering out the nails one by one.

That is, when driving a single nail, fluid pressure is introduced into the piston upper chamber B1 of the main cylinder B, and residual air in the piston lower chamber B2 is released to the atmosphere to drive the main piston A. It is rapidly moved forward from the top dead center toward the bottom dead center, and after the nailing is completed, return fluid pressure (spring pressure, etc. can be used in some cases) is applied to the main piston lower chamber B2 at the bottom dead center position. The upper chamber B1 of the main piston is opened to the atmosphere, and the main piston is moved back from the bottom dead center position toward the top dead center.

Then, the main piston A is at the bottom dead center position,
The receiver is designed to be stopped by a bumper member F made of a hard rubber material, etc., but this bumper member F is designed to be strong enough to withstand the extremely large impact force of the main piston A directly. Therefore, it is formed as an integral piece in the shape of a thick block.

Therefore, when this bumper member F is formed from a rubber material or the like, variations in the molding structure are likely to occur between the inner wall center area and the outer periphery area, making it difficult to create a bumper with uniform properties as a whole. Met.

In addition, since this type of nailing machine is used to drive a large number of nails continuously and rapidly, the collision between the main piston A and the bumper member F occurs repeatedly, and at extremely high speeds. Since the bumper member F is heated rapidly, there is a risk that the bumper member F will be seized.

Particularly in the case of a bumper with a large mass, it is difficult for heat to be released from the central part due to the characteristics of the rubber.

In addition, as mentioned above, if there is variation in properties between the center of the wall thickness and the outer surface, the bumper member F will be subject to severe wear and tear, making it impossible to use it continuously for a long time, and requiring frequent maintenance and inspection. .

The present invention has been proposed in view of such conventional circumstances, and aims to provide a highly reliable bumper for stopping the main piston of a nailer at the bottom dead center. .

Furthermore, it is an object of the present invention to form a bumper with less variation in properties as a whole.

Another object of the present invention is to sufficiently prevent the bumper from rising during nail driving operations.

Furthermore, another object of the present invention is to provide a bumper device in which the bumper can be easily and accurately assembled near the lower end of the main cylinder, and the assembled state is stable.

Furthermore, the present invention aims to provide a bumper that is easy to manufacture and process and has excellent mass productivity.

A further object of the present invention is to provide a bumper that can release the back pressure during nail driving, that is, when the main piston moves forward, that is, can smoothly exhaust the lower chamber of the main piston.

The bumper device of the present invention includes a bumper that is disposed at the lower end of a main cylinder built into the main body of the nailer, and that receives and holds the main piston, which is slidably and tightly fitted into the main cylinder, at the bottom dead center position. , separated into a block group consisting of several blocks that are independent of each other through a gap that penetrates at least in the axial direction of the bumper, and these blocks have a driver through hole near the center and a main cylinder at the outermost periphery. It is characterized in that it is held at the lower end.

Embodiments of the present invention shown in the drawings will be described below.

2 and 3 illustrate a first embodiment of the present invention, and each of these figures shows a vertical cross-section of the main part of a nailing machine with a bumper installed.

In the figure, 1 is a bumper, and in this example, two independent annular blocks, an outer ring block 11 which is the outer bumper part and an inner ring block 12 which is the inner bumper part, are divided into two in the radial direction. I try to assemble and use it.

Reference numeral 2 denotes a nailing machine main body, which has a main cylinder 3 built therein and a nose 4 disposed at its lower end.

That is, the diameter of the vicinity of the lower end 2a of the main body 2 is reduced, and the lower end 31 of the main cylinder 3 is tightly fitted and held therein, and furthermore, the lower end is provided with a connecting portion provided at the base end of the nose 4 (upper end side in the figure). 41 are integrally connected.

As a result, the nose 4 has a driver guide hole 42 formed through the nose 4 in its axial direction and protrudes coaxially with the lower ends of the main body 2 and the main cylinder 3.

The inner wall of the connecting part 41 of the nose 4 has a flat part 41b inside the annular inclined surface 41a on the outer circumferential side, and further has a stepped part 42 in which the driver guide 5 is fitted and held.
is formed, and the iron part 42 has a driver insertion hole 51 in the center.
A driver guide 5 having a diameter is loosely fitted therein.

A flange portion 52 is formed at the upper end of the driver guide 5 in the figure, and its surface 52a serves as a receiving portion for the seating portion 12b of the inner block 12, and further between the flange portion periphery 52a' and the stepped portion peripheral wall 42a. The gap 8 is maintained.

The connecting portion 41 also includes a corner portion 4 of the stepped portion 42.
An opening 43 is provided that communicates 2b with the outside.

6 is a main piston, and an O-ring 6 is installed in the main cylinder 3 so that it can move freely in the vertical direction in the figure.
1 and are tightly fitted.

A female threaded hole 62 for connecting a driver is formed in the direction of the solid axis of the piston 6, and a male threaded part 71 formed at the base end of the driver 7 is screwed into this part 62.
are combined into one.

A large diameter portion 3C forming a bumper holding portion is formed on the inner circumferential wall of the lower end portion 31 of the main cylinder 3 and has a slightly larger diameter than the cylinder main diameter portion 3a from the step portion 3b. There is.

The outer ring block 11 of the bumper 1 has a piston contact surface 11a annularly abutting against the lower surface 6a of the piston 6 on the upper end surface in the axial direction, and further has the nose on the lower end surface in the axial direction and the outer periphery on the lower end side. A seating part 11b is formed for the inclined surface 41a and the flat part 41b of the connecting part 41, and furthermore, the outer circumferential wall bulges out most outwardly in the middle part in the height direction, and becomes an outwardly bulging part 11c, and furthermore, An upper tapered portion 11d and a lower tapered portion 11e are continuously formed, the diameter of which gradually decreases toward the upper and lower ends in the axial direction.

Note that the vicinity of the outwardly bulging portion 11C is fitted into the large diameter portion 3C of the main cylinder 3, and is locked by the step portion 3b.

In addition, the inner through-hole peripheral wall 11' is provided with an inward bulge 11f so as to have a minimum diameter at a slightly upper position in the middle, and from this bulge 11f to each of the upper and lower end surfaces in the axial direction. An upper tapered portion 11g and a lower tapered portion 11h, which face each other and gradually expand in diameter, are continuously formed.

Further, the inner ring block 12 has a driver insertion hole 13 formed in the center thereof so as to pass through it in the vertical direction, and an annular main piston contact surface 12a is formed in the upper end surface in the axial direction. The driver guide 5 is attached to the end surface.
An upper seating portion 12b is formed.

Although the diameter of the driver insertion hole 13 is slightly longer than the shaft diameter of the driver 7, the difference in diameter is small.

Further, upper and lower opening ends in the axial direction of the driver insertion hole 13 are formed with an upper tapered hole portion 12c and a lower tapered hole portion 12d whose diameters increase toward the end surface side, and of these, the upper tapered hole portion 12c is the main hole portion 12c. The base flange portion 7 of the driver 7 connected to the piston 6 when in contact with the piston 6
1' can be supported from below in the figure.

Furthermore, the outer circumferential wall 12' of the inner ring block 12 has an outwardly bulging portion 12 which has its maximum diameter at a position slightly lower than the midway point in the axial direction.
e, and an upper tapered portion 12f and a lower tapered portion 12g are continuously formed from the iron portion 12C to the upper and lower ends, the diameter of which gradually decreases.

The inner diameter of the inward bulging portion 11f, which is the smallest diameter portion of the inner through hole 13A of the outer ring block 11, is greater than the outer diameter of the outer bulging portion 12e of the outer peripheral wall 12' of the inner ring block 12. Short and through hole 13 of outer ring block 11
What is the inner peripheral wall surface of the downwardly tapered hole portion 11h extending from the inwardly bulging portion 11f of the B inner peripheral wall 11′ toward the lower end, and the outer peripheral wall surface of the upper tapering portion 12f extending from the outwardly bulging portion 12e of the inner block 12 toward the upper end? The angles of inclination are such that they are parallel to each other, and sometimes the inner peripheral wall surface 11' and the outer peripheral wall surface 12' are assembled.
A small gap is maintained between them.

Further, the heights of the outer ring block 11 and the inner ring block 12 are the same, so that each piston contact surface 11
a and 12a are flush with each other.

Furthermore, the upper and lower sides of the bumper 1 in the axial direction, that is, the upper and lower sides in FIG. The inner ring block 12 is in communication in the vertical direction through the driver insertion hole 13A of the inner ring block 12.

In the above configuration, the bumper 1 is located at the stepped portion 3 of the main cylinder 3 at the outwardly bulging portion 11c on the outer periphery of the outer ring block 11.
b, and furthermore, the inner ring block 12 has an upper tapered part 12f upward from its outward bulging part 12e, and the upper tapered part 12f engages with the outer ring block 1.
1, the inwardly bulging portion 11f of the main cylinder 3 is relatively engaged with the lower tapered portion 11h of the lower part, and the main cylinder 3 is prevented from falling upward in FIG.
A stable installation condition can be obtained at the lower end of the

This means that a stable installation condition can be obtained even when the nailer is used for ceiling driving, that is, when the nose 7 is directed upward and the nail is driven from below onto the surface to be nailed (not shown). become.

In addition, in the bumper 1, a gap is maintained between the outer ring block 11 and the inner ring block 12 that can penetrate vertically in the axial direction. Air flows through the gap together with the driver insertion hole 13A of the outer ring block 12 and the inner ring block 12, that is, after the entire outer circumferential surface of the outer ring block 11 and the entire outer circumferential surface of the inner ring block 12 are sufficiently contacted with air, the air flows outside through the opening 43. By exhausting the air, it is possible to very effectively suppress the rise in temperature of the bumper 1 due to the heat of compression.

In addition, the bumper 1 has outer ring and inner ring blocks 11°12
Since the blocks 11 and 12 can be separately formed and assembled together for use, the mass of each block 11 and 12 can be reduced compared to the case where the entire bumper 1 is integrally molded during molding, and the properties can be made uniform. The heat of compression can be dissipated extremely effectively.

Further, as in the above embodiment, the lower end seating portion 11b of the outer ring block 11 and the lower end seating portion 12 of the inner ring block 12 are provided.
Since it is extremely easy to design the space between the outer periphery 51b of the flange portion of the driver guide 5 and the peripheral wall 42a of the stepped portion 42 as shown in FIG. Damage caused by biting of the bumper 1 in the above-mentioned space due to the rattling of the driver guide 5 can be easily avoided.

In addition, when assembling the bumper 1, before assembling the nose 4, first fit the outer ring block 11 from the lower end side of the open main cylinder 3 in FIG. The inner ring block 12 is fitted into the internal hole of the nose 4, and then the nose 4 can be assembled together with the driver guide 5 so as to close the lid.

In this case, if the bumper 1 is integrally formed as a whole, it is extremely difficult for an operator to bend it by hand, so there is a drawback that fitting the bumper 1 into the lower end of the main cylinder 3 becomes complicated.

However, in the present invention, the outer ring block 11 is formed in an annular shape independent of the inner ring block 12, and a large through hole is formed in the central portion, so it is easy to bend, and therefore it is extremely easy to assemble. The attached person can perform the work.

Also, when removing the bumper 1 for repairs etc., it is easy to remove the driver guide 5 together with the nose 4, first remove the inner ring block 12 from the outer ring block 11, and then remove the outer ring block 11. Can be removed.

Particularly when the bumper 1 is slightly deformed after being used for a long period of time, each block 11, 12 is bent individually, which is a great effect.

Further, FIGS. 4 and 5 show another embodiment of the present invention in which a part of the embodiment described above is modified.

In these drawings, the same reference numerals as in FIGS. 2 and 3 designate the same members, and therefore, explanations of the common parts will be omitted.

Therefore, in the case of this embodiment, the gap between the outer ring block 11 and the inner ring block 12 is maintained wider than that of the previous embodiment, and in this example, the outer peripheral wall surface of the inner ring block 12 is A large number of protrusions 10 extending in the axial direction and having a semicircular cross section are arranged in parallel and distributed in a circumferentially spaced manner.

Then, when the inner ring block 12 is fitted into the inner through hole 13B of the outer ring block 11, each top of each of the protrusions 10 expands at least inwardly on the inner peripheral wall 11' of the outer ring block 11. Tapered portion 11h extending from the exit portion 11f toward the lower end in the axial direction
It is in contact with.

As a result, between the outer ring and inner ring hook blocks it, 12, there are protrusions 10. A large number of voids are formed which are surrounded by the bumper 1 and communicate with each other in the vertical direction in the axial direction of the bumper 1.

In this example, the gap between the outer ring and inner ring hook blocks 11 and 12 is maintained at a sufficiently wide width, and the inner ring block 12 is accurately inserted into the through hole 13B of the outer ring block 11 by each protrusion 10. It is installed in a positioned state.

Note that the protruding portion 10 is formed in the through hole 1 of the outer ring block 11.
3B on the inner peripheral wall 11', or on the inner ring block 12
It may be arranged on both the outer peripheral wall 12' of the outer ring block 11 and the inner peripheral wall 11' of the outer ring block 11.

Furthermore, the same effect can be obtained even if a large number of protrusions are provided in place of the protrusion 10.

Also in this embodiment, the same effects as in the previous embodiment can be achieved.

As is clear from the above-mentioned embodiments, the present invention can sufficiently achieve the intended purpose.

It should be noted that the present invention is not limited to the structures shown in each of the above embodiments, but includes the structures shown in the claims, and also includes various other modifications.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view schematically showing the structure of a conventional nailing machine equipped with a bumper. FIG. 2 and FIG. 3 are diagrams showing one embodiment of the present invention,
FIG. 2 is a longitudinal cross-sectional view of a main part, and FIG. 3 is a cross-sectional view taken along the line II in FIG. 2. 4 and 5 are views showing other embodiments of the present invention, in which FIG. 4 is a longitudinal cross-sectional view of a main part, and FIG. 5 is a cross-sectional view taken along the line V--V in FIG. 4. 1... Banha, 2... Nailer body, 3
...Main cylinder, 4...Nose,
6...Main piston, 7...Driver, 10...Protrusion, 11...Outer ring block, 12...Inner ring Block, 13A...
...Driver insertion hole, 13B...Through hole in outer ring block, 14...Gap between each block.

Claims (1)

[Scope of Claims] 1. A bumper that is disposed at the lower end of a main cylinder built into the nailing machine body and that receives and stops the main piston, which is slidably and tightly fitted into the main cylinder, at the bottom dead center position. , are formed separately as a block group consisting of several blocks that are independent from each other through a gap that penetrates at least in the axial direction of the bumper, and these block groups have a driver insertion hole penetratingly formed near the center part, and a driver insertion hole is formed in the outermost peripheral part of the block group. A bumper device for a nail gun, characterized in that it is held at the lower end of a main cylinder. 2. A bumper that is disposed at the lower end of the main cylinder built into the nailer body and that receives and stops the main piston, which is slidably and tightly fitted into the main cylinder, at the bottom dead center position, and the bumper has an outer circumferential portion. The main cylinder has an outer bumper part formed in an annular shape and held at the lower end of the main cylinder, and an inner bumper part disposed inside the outer bumper part and having a driver insertion hole in the center. In addition to being formed as independent blocks, there is a gap between each of the blocks that penetrates in the axial direction at least under normal conditions, and between each adjacent block, it is possible to prevent the inner block from being pulled out and falling toward the main piston side. A bumper for a nail gun, characterized in that a relative engagement means is arranged. 3. Separate at least in the circumferential direction a bumper that is disposed at the lower end of the main cylinder built into the nailer body and that receives and holds the main piston, which is slidably and tightly fitted into the main cylinder at the bottom dead center position. When the inner block is assembled into several blocks that are independently formed, the inner circumferential wall of the outer block of the adjacent block tanks has an inclined wall that tapers toward the main piston. and the outer peripheral wall surface of the inner block has an inclined outer wall portion that tapers in the direction of the main piston, and the maximum diameter portion of this outer peripheral side wall has a longer diameter than the minimum diameter portion of the hole when the inner block is assembled. A bumper for a nail gun characterized by the following features: 4. Separate at least in the circumferential direction a bumper that is disposed at the lower end of the main cylinder built into the nailer body and that receives the main piston, which is slidably and tightly fitted into the main cylinder, at the bottom dead center position. The independent form is applied to several blocks,
The outer periphery of these blocks is held at the lower end of the main cylinder, and the inner periphery is provided with a driver insertion hole that penetrates in the vertical direction, and each adjacent block has communication in the vertical direction at least under normal conditions. 1. A bumper for a nailing machine, characterized in that a bumper for a nailing machine is provided with relative engagement means capable of retaining a possible gap and preventing each block from being pulled out and falling in the direction of a main piston.