JP2576575Y2 - Nail driver shock absorber - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber for a nailing machine for driving a nail by the impact of a driving piston.

[0002]

2. Description of the Related Art In general, a nail driving machine which drives a driving piston with compressed air and hits and drives a nail with a driver connected to the driven driving piston has a shock absorber for absorbing the impact of the driving piston. Is provided. This type of shock absorber is constituted by a cylindrical bumper.

In recent years, regulations on air pressure have been greatly eased, and high-pressure compressed air of up to 50 kgf / cm ² has been used. This has made it possible to design a small, high-power nailing machine. Became.

However, since the outer diameter of the driving piston cannot be increased in order to keep the nailing machine small, the outer diameter of the bumper that receives the lower surface of the driving piston cannot be increased. On the other hand, when high-pressure compressed air is used, the impact force of the drive piston becomes large, so that it is necessary to increase the overall volume of the bumper and increase the mass of the bumper. When the mass of the bumper is increased, the outer diameter is limited, so that it is necessary to increase the height of the bumper.

However, in a structure in which the bumper is simply raised, when the impact of the drive piston is received, the impact force of the drive piston is transmitted only to the upper portion of the bumper and is hardly transmitted downward. Thus, the impact load of the drive piston is biased only to the upper part of the bumper, only the upper part is largely bent, and the upper edge of the bumper that has been deformed and expanded at that time is sandwiched between the inner surface of the cylinder and the outer peripheral surface of the drive piston. Therefore, there is a problem that chipping cracks occur in this portion within a short period of time and durability is impaired.

[0006]

The object of the present invention is to solve the above-mentioned drawbacks, and to effectively absorb the impact of the driving piston without increasing the outer diameter of the bumper, particularly by a structure that uniformly absorbs the impact of the driving piston throughout the bumper. It is another object of the present invention to provide a shock absorber for a nailing machine which can prevent the durability of a bumper from being impaired.

[0007]

In order to achieve the above object, a shock absorber for a nailing machine according to the present invention has a driving piston slidably housed in a driving cylinder and a driver provided on a lower surface of the driving piston. In a nailing machine, the driving piston is driven by compressed air to drive the nail supplied to the injection portion at the tip of the nailing machine body by a driver.
Between the drive cylinder and the injection portion, a housing portion of the bumper that receives the lower surface of the drive piston is formed in a vertically long shape , and an upper outer peripheral surface of a vertically long cylindrical bumper housed in the housing portion is defined as a housing portion. while guided by the inner surface, the drive pin
Inner peripheral surface of bumper when stone hits upper surface of bumper
And a sufficient gap between the outer peripheral surface of the driver and
Characterized in that the formation of the air gap between the lower outer peripheral surface and the housing portion of the inner surface of only deformable manner vans <br/> path in the thin lower bumper.

[0008]

According to the above construction, the volume of the bumper is increased as a whole by making the bumper vertically long, so that the impact of the driving piston driven at a high pressure can be effectively absorbed.

Further, when the bumper is compressed and deformed by receiving the impact load of the driving piston, the upper outer peripheral surface of the bumper is guided by the inner surface of the accommodating portion, so that it cannot be deformed outward but deformed inward and downward. And A gap is formed between the outer peripheral surface of the lower part of the bumper and the inner surface of the storage part, so that the deformation of the compressed bumper can escape. Also, the lower part of the bumper is thin and easy to deform
Is formed. For this reason, the upper part of the bumper is
Is compressed and deformed inward by the direct impact of
The lower part of the pad is easy to deform, and the gap where the deformation escapes
Voids are inside and outside. For this reason, the upper and lower portions of the bumper are entirely deformed. Since only the upper end of the bumper is not greatly deformed as in the related art, chipping cracks are effectively prevented, and durability is not impaired even when high-pressure compressed air is used.

Therefore, according to the present invention, a shock absorber suitable for a high-pressure and small-sized nailing machine can be obtained.

[0011]

FIG. 1 shows a pneumatically driven nail driver.
In this nailing machine, a driving piston 2 is slidably housed in a driving cylinder 1, a driver 3 is integrally connected to a lower surface of the driving piston 2, and the driving piston 2 is driven to nail the driver 3. The nail is supplied to the injection section 5 at the tip of the machine body 4. An air chamber 7 for storing compressed air supplied from a compressed air supply source (air compressor) 6 via a grip portion is formed in the nailer body 4, and the compressed air in the air chamber 7 is operated by a trigger. Drive cylinder 1 according to opening and closing of main valve 8
The driving piston 2 is supplied to the upper surface of the driving piston 2 inside, thereby driving the driving piston 2. When the drive piston 2 is driven downward, the lower air in the drive cylinder 1 is compressed. Therefore, the compressed air flows from the communication hole 9 formed in the lower portion of the drive cylinder 1 into the blowback chamber 10. And stored. When the drive piston 2 reaches the bottom dead center, the upper surface of the drive piston 2 communicates with the atmosphere through an exhaust hole (not shown) to reduce the pressure. 2 acts on the lower surface of the drive piston 2 by the pressure difference between the upper and lower surfaces.
Moves upward and returns to top dead center.

As shown in FIG. 2, a housing 12 for a bumper 11 is formed between the drive cylinder 1 and the injection section 5, and the bumper 11 housed in the housing 12 is a lower surface of the drive piston 2. As a result, the impact force of the drive piston 2 is absorbed.

The accommodation portion 12 of the bumper 11 is formed to be vertically long, and the upper portion is formed to have the same diameter, but the lower portion swells outward and the inner diameter is formed to be large. A through hole 14 for the driver 3 is formed in the lower surface of the housing portion 12 and communicates with the emission portion 5. Further, the driving piston hits the upper surface of the bumper 11.
The inner peripheral surface of the bumper 11 and the outer peripheral surface of the driver 3
Are formed between them.

The bumper 11 has a vertically long cylindrical shape in accordance with the shape of the accommodating portion 12, and has an insertion hole 15 formed therein for allowing the driver 3 of the drive piston 2 to pass therethrough. Bumper 1
The upper part 11 a of the first part 11 is thick and has an outer diameter substantially equal to the inner diameter of the housing part 12. On the other hand, the intermediate part 11
b swells along the inner surface of the swelling at the lower part of the housing portion 12,
The lower part 11c is dented and formed to be thin. As a result, the overall volume of the bumper 11 increases in the vertical direction, and a gap S is formed between the outer peripheral surface of the lower portion 11c and the inner surface of the housing portion 12. Further, the upper end of the bumper 11 is formed to be substantially the same as the lower end of the communication hole 9 of the drive cylinder 1 in a state of being housed in the housing portion 12. The bumper 11 may be made of low nitrile rubber or NBR resin.

According to the above configuration, the lower surface of the actuated drive piston 2 is impacted against the upper surface of the bumper 11. The bumper 11 receives the impact load of the driving piston 2 and is compressed and deformed. At this time, since the outer peripheral surface of the upper part 11a of the bumper 11 is guided by the inner surface of the housing part 12, the bumper 11 cannot be deformed outward, but tends to be bent inward and downward. The lower portion 11c of the bumper 11 is thin and easily deformed, and is formed with the inner peripheral surface of the bumper 11.
A sufficient gap is formed between the outer peripheral surface of the driver 3 and
A gap S is provided between the outer peripheral surface of the lower portion and the inner surface of the accommodation portion 12.
Are formed so that the deformation of the compressed bumper 11 escapes to the inside and outside . As described above, since the lower portion 11c of the bumper 11 is formed so as to be easily deformed with respect to the upper portion 11a, as shown in FIG.
Is deformed as a whole without being biased upward or downward . Since only the upper end of the bumper is not greatly deformed as in the related art, chipping cracks are effectively prevented, and durability is not impaired even when high-pressure compressed air is used.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a nailing machine according to the present invention.

FIG. 2 is a sectional view of the shock absorber according to the present invention.

FIG. 3 is an explanatory diagram of an operation state of the shock absorber.

[Explanation of symbols]

 S Air gap 1 Drive cylinder 2 Drive piston 3 Driver 4 Nailer body 5 Injection unit 11 Bumper 12 Housing

Claims (1)

(57) [Scope of request for utility model registration] A driving piston is slidably housed in a driving cylinder, a driver is integrally connected to a lower surface of the driving piston, the driving piston is driven by compressed air, and the driver is driven by a driver at a tip end of the nailing machine main body. vertical in nailing machines come up supplied to the injection unit nail, between the drive cylinder and the injection unit, the housing portion of the bumper for receiving a lower surface of the drive piston is vertically long form, it is accommodated in the housing section while guided by the inner surface of the housing portion of the upper outer peripheral surface of the long cylindrical bumper direction, the drive pin
Inner peripheral surface of bumper when stone hits upper surface of bumper
And a sufficient gap between the outer peripheral surface of the driver and
Damping device of the nailing machine, characterized in that the formation of the air gap between the lower outer peripheral surface and the housing portion of the inner surface of the bun <br/> path in the thin so that only the easily deformed bottom of the bumper.