JPH0717481U - Nailer shock absorber - Google Patents

Abstract

(57) [Summary] [Structure] A housing portion 12 of a bumper 11 for receiving the lower surface of the drive piston 2 is formed vertically between the drive cylinder 1 and the injection portion 5, and a bumper housed in the housing portion 12 is formed. The upper outer peripheral surface of 11 is guided by the inner surface of the housing portion 12, and a space S is formed between the lower outer peripheral surface of the bumper 11 and the inner surface of the housing portion 12. [Effect] Since the volume of the bumper 11 is increased, the impact of the drive piston 2 can be effectively absorbed. When the bumper 11 is deformed, its upper outer peripheral surface is guided by the inner surface of the accommodating portion 12 and cannot be deformed, and tends to deform inward and downward. A space S is formed in the lower portion of the bumper 11 so that the compressed deformation of the bumper 11 can escape. Therefore, the upper portion of the bumper 11 is less likely to be deformed and the lower portion is likely to be deformed, so that the bumper 11 is entirely deformed and durability is not impaired.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a shock absorber for a nail driving machine that drives a nail by the impact of a drive piston.

[0002]

[Prior art]

 Generally, a nailing machine in which compressed air is used to drive a drive piston and a driver connected to the driven drive piston strikes a nail to drive the nail is provided with a shock absorber for absorbing the impact of the drive piston. ing. This type of shock absorber is composed of a tubular bumper.

By the way, recently, restrictions on the air pressure used have been greatly relaxed, and compressed air with a high pressure up to 50 Kgf / cm ² can be used. With this, the design of a compact and high-power nailing machine has been advanced. Became possible.

However, since the outer diameter of the drive piston cannot be increased in order to keep the nailer compact, the outer diameter of the bumper that receives the lower surface of the drive piston cannot be increased. On the other hand, in order to use high-pressure compressed air, the impact force of the drive piston becomes large, so it is necessary to increase the overall volume of the bumper and increase the mass of the bumper. When increasing the mass of the bumper, there is a limit to the outer diameter, so it is unavoidable to increase the height.

However, in the 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 concentratedly transmitted only to the upper portion of the bumper and is difficult to be transmitted downward. In this way, 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 deformed and extended 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 purpose of the device]

 The present invention eliminates the above-mentioned drawbacks, and in particular, the structure that uniformly absorbs the impact of the drive piston in the entire bumper effectively absorbs the impact of the drive piston without increasing the outer diameter of the bumper and makes the bumper durable. It is an object of the present invention to provide a cushioning device for a nail driver that can prevent the deterioration of the property.

[0007]

[Means for achieving the purpose]

 To achieve the above object, a shock absorber for a nailing machine according to the present invention accommodates a drive piston slidably in a drive cylinder and integrally connects a driver to a lower surface of the drive piston to provide compressed air. In the nailing machine that drives the drive piston by the driver to drive out the nails supplied to the injection section at the tip of the nailing machine main body, the bumper is received between the drive cylinder and the injection section to receive the lower surface of the drive piston. The upper part of the bumper housed in the housing part is guided by the inner surface of the housing part, and a gap is formed between the lower outer surface of the bumper and the inner surface of the housing part. Is characterized by.

[0008]

[Function and effect of the device]

 According to the above construction, the volume of the bumper is increased as a whole by making the bumper vertically long, so that it is possible to effectively absorb the impact of the drive piston driven at high pressure.

Further, when the bumper is compressed and deformed by the impact load of the drive piston, the outer peripheral surface of the upper part of the bumper is guided by the inner surface of the accommodating portion, so that the bumper cannot be deformed to the outside, and can be deformed inward and downward. And A space is formed between the outer peripheral surface of the lower part of the bumper and the inner surface of the accommodating portion so that the compressed deformation of the bumper can escape. In this way, the bumper is formed so that the upper portion is not easily deformed and the lower portion is easily deformed, so that the bumper is deformed as a whole. Unlike the conventional case, only the upper end of the bumper is not greatly deformed, so 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]

【Example】

 FIG. 1 shows a pneumatically driven nail driving machine. This nailing machine accommodates a drive piston 2 in a drive cylinder 1 slidably, and a driver 3 is integrally formed on a lower surface of the drive piston 2. , And drives the drive piston 2 to drive out the nail supplied by the driver 3 to the injection portion 5 at the tip of the nailer main 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 nailing machine body 4, and the compressed air in the air chamber 7 is triggered. It is supplied to the upper surface of the drive piston 2 in the drive cylinder 1 in response to the opening and closing of the main valve 8 which is operated by, and the drive piston 2 is driven by this. 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 part of the drive cylinder 1 into the blowback chamber 10. Is pumped to and stored. When the drive piston 2 reaches the bottom dead center, the upper surface of the drive piston 2 is communicated with the atmosphere through an exhaust hole (not shown) to reduce the pressure, so that the compressed air in the blowback chamber 10 is driven from the communication hole 9 through the communication hole 9. Acting on the lower surface of the stone 2, the drive piston 2 moves upward due to the pressure difference between the upper and lower surfaces, and returns to the top dead center.

As shown in FIG. 2, an accommodating portion 12 of the bumper 11 is formed between the drive cylinder 1 and the injection portion 5, and the bumper 11 accommodated in the accommodating portion 12 has a lower surface of the drive piston 2. Accordingly, the impact force of the drive piston 2 is absorbed.

The accommodating portion 12 of the bumper 11 is formed in a vertically long shape, and the upper portion has the same diameter, but the lower portion bulges outward and the inner diameter has a large diameter. A through hole 14 for the driver 3 which communicates with the injection part 5 is formed on the lower surface of the housing part 12.

The bumper 11 has a vertically long tubular shape according to the shape of the housing portion 12, and has an insertion hole 15 formed therein for inserting the driver 3 of the drive piston 2. The upper portion 11a of the bumper 11 is thick, and its outer diameter is formed to be substantially the same as the inner diameter of the housing portion 12. On the other hand, the intermediate portion 11b bulges along the bulging inner surface of the lower portion of the accommodating portion 12, and the lower portion 11c is dented and thinly formed. As a result, the volume of the entire bumper 11 increases in the vertical direction, and a space S is formed between the outer peripheral surface of the lower portion 11c and the inner surface of the accommodating portion 12. Further, the upper end of the bumper 11 in the state of being accommodated in the accommodating portion 12 is formed to the same extent as the lower end of the communication hole 9 of the drive cylinder 1. 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 impacts the upper surface of the bumper 11 in an impact. The bumper 11 receives the impact load of the drive piston 2 and is compressed and deformed. At this time, since the outer peripheral surface of the upper portion 11a of the bumper 11 is guided by the inner surface of the accommodating portion 12, the bumper 11 cannot be deformed to the outside, and tends to be deformed by bending inward and downward. The lower portion 11c of the bumper 11 is thin and is easily deformed, and a gap S is formed between the outer peripheral surface of the lower portion and the inner surface of the accommodating portion 12 so that the deformed portion of the compressed bumper 11 escapes. Is formed. As described above, since the upper portion 11a of the bumper 11 is not easily deformed and the lower portion 11c is easily deformed, the deformation of the bumper 11 is entirely deformed as shown in FIG. . Unlike the conventional case, only the upper end of the bumper is not significantly deformed, so chipping cracks are effectively prevented, and durability is not impaired even when high-pressure compressed air is used.

[Brief description of drawings]

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

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

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

[Explanation of symbols]

 S Air gap 1 Drive cylinder 2 Drive piston 3 Driver 4 Nail driver main body 5 Injection part 11 Bumper 12 Storage part

Claims (1)

[Scope of utility model registration request] 1. A drive piston is slidably accommodated in a drive cylinder, a driver is integrally connected to the lower surface of the drive piston, and the drive piston is driven by compressed air to drive the drive piston at the tip of the nailing machine main body. In a nail driving machine for driving a nail supplied to an injection portion, a bumper housing portion for receiving a lower surface of a drive piston is formed vertically between the drive cylinder and the injection portion, and a bumper housed in the housing portion is formed. A shock absorber for a nailing machine, characterized in that the upper outer peripheral surface of the above is guided by the inner surface of the accommodating portion, and a gap is formed between the lower outer peripheral surface of the bumper and the inner surface of the accommodating portion.