JPH0516162U - Shock absorber for nailer - Google Patents

Abstract

(57) [Summary] [Structure] Lower surface a of the bumper 5 on the nose portion 4
Is formed in a flat shape, a tapered receiving surface b is continuously formed outside the flat receiving surface a, and the lower end outer peripheral portion of the bumper 5 is supported by the tapered receiving surface b. A support was provided with a gap between the lower surface and the flat receiving surface a. [Effect] When the lower surface of the striking piston 2 is received by the bumper 5 and stops, the bumper 5 that has received an impact causes a slip between the impact receiving piston 2 and the tapered receiving surface b and moves while deforming inward to provide an initial cushion. Then, the flat cushioning surface ab is brought into contact with the flat receiving surface ab to be deformed downward to perform secondary cushioning. 2 above
Since the amount of deformation of the bumper 5 is increased by the step buffer, the impact noise is reduced. Moreover, since the amount of deformation in the vertical direction is small, the driving force is stably maintained.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock-cushioning device for a nailing machine that shocks when a striking piston is driven to reduce shock noise.

[0002]

[Prior art]

 In general, a bumper that cushions the impact of the impact piston of the nail driver is arranged below the impact cylinder. The bumper is usually made of hard rubber in order to determine the stopping position of the striking piston, and its lower surface is supported by a flat surface.

By the way, when the striking piston collides with the bumper, an excessive impact force of the striking piston into which the nail is driven is shock-propagated to the machine body of the nailing machine through the bumper, and an impact sound is generated. The volume of the bumper should be increased to suppress such impact noise. However, in order to increase the volume of the bumper, it is necessary to increase the storage space of the bumper, which inevitably causes the nailing machine to become large in size, which causes a problem that the weight also increases. On the other hand, instead of increasing the volume of the bumper, it is possible to increase the amount of deformation of the bumper to cause the striking piston to strike the stroke with a long stroke. Since the amount of deformation of the bumper slightly changes with each impact, the stop position of the impact piston is not fixed, and the nail driving force (driving depth) becomes unstable.

[0004]

[The purpose of the device]

 SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks and to provide an impact shock absorbing device for a nailing machine, which can reduce the impact noise without increasing the volume of the bumper or the deformation amount in the impact direction. .

[0005]

In order to achieve the above object, an impact shock absorber for a nailing machine according to the present invention is a striking cylinder that slidably accommodates a striking piston for striking a nail, and the striking cylinder. Has a nose portion which extends downwardly of the nose portion for accommodating the nail and which guides the sliding movement of a driver integrally connected to the impact piston, and the upper end of the nose portion receives the impact piston at the time of impact. In a nailing machine in which a bumper is arranged, a receiving surface for receiving the lower surface of the bumper is formed into a flat shape, a tapered receiving surface is continuously formed outside the flat receiving surface, and the outer peripheral portion of the lower end of the bumper is formed into a flat shape. It is characterized in that it is supported by a tapered receiving surface, and is supported with a gap between the lower surface of the bumper and the flat receiving surface. It is preferable that a protrusion is formed so as to project from the lower surface of the bumper, and the protrusion is brought into contact with the flat receiving surface to support the bumper.

[0006]

[Function and effect of the device]

 According to the above configuration, when the striking piston is driven, the lower surface of the striking piston is received by the bumper and stops. At this time, the bumper that receives the impact of the striking piston slides against the taper receiving surface of the nose member and moves while deforming inward, during which part of the impact force of the striking piston is absorbed. Is absorbed by the elastic deformation and slip resistance of the bumper, and the initial cushioning is performed, and immediately after that, the lower surface of the bumper abuts the flat bearing surface, and this deformation absorbs the rest of the impact force of the striking piston, which is the same as in normal times. Secondary buffering is performed. In this way, the impact of the striking piston by the bumper is performed in two steps, and the amount of deformation of the bumper for cushioning is longer than in the conventional case, so the impact noise is reduced. Moreover, the deformation due to the initial buffering is the deformation along the taper receiving surface, which means that the damper is deformed inward, and the amount of vertical deformation is small. Therefore, the piston stop position by the bumper is almost the same as the conventional one, and the driving force is stably maintained.

If the bumper is supported by the protrusion protruding from the lower surface of the bumper, the bumper can be returned and moved after being buffered with a simple structure.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a main part of a nailing machine. The nailing machine is slidably housed in an impact cylinder 1 and inside thereof. The striking piston 2 and the nail striking driver 3 extending below the striking cylinder 1 and integrally connected to the striking piston 2 are guided, and the nails supplied from the nail supply mechanism are accommodated. And a compressed air is supplied to and discharged from the striking cylinder 1 by the opening / closing operation of a head valve (not shown) provided above the striking cylinder 1. It is driven to hit the nail in the nose portion 4 to drive it out.

A housing portion 6 for a bumper 5 that receives the striking piston 2 at the time of striking is formed at the upper end of the nose portion 4, and the bumper 5 is arranged in the housing portion 6. The receiving surface of the bumper 5 in the housing portion 6 is formed such that the receiving surface a for receiving the lower surface of the bumper 5 is flat and the receiving surface b continuous to the outside is tapered. The receiving surface c that receives the side surface of the bumper 5 at the upper part of the tapered receiving surface b is connected to the lower end of the striking cylinder 1 via the step portion 7, so that the bumper 5 is engaged with the step portion 7. It is designed so that it does not jump out of the storage section 6.

On the other hand, the bumper 5 is formed of an elastic synthetic rubber, synthetic resin, or the like in an annular shape, and a bulging projection 5 a is formed on the outer peripheral surface so as to engage with the step 7. . In addition, the outer peripheral portion of the lower end of the bumper 5 is supported by the tapered receiving surface b, and the projection 5b is formed on the lower surface of the bumper 5, and the projection 5b is brought into contact with the flat receiving surface a. The bumper 5 is supported with a gap S between it and the flat receiving surface a. A spring (not shown) may be arranged below the bumper 5 instead of the protrusion 5b, but the structure is slightly complicated.

In the above structure, when the striking piston 2 is driven, the lower surface of the striking piston 2 is received by the bumper 5 and stops. At this time, as shown in FIG. 2, first, the outer peripheral edge of the lower end of the bumper 5 whose upper end surface receives the surplus impact force of the hammering impact piston 2 becomes the tapered receiving surface b of the nose portion 4 material. The entire bumper 5 is moved downward while the lower end of the cylindrical bumper 5 is deformed inward by sliding between them, during which part of the impact force of the striking piston 2 is absorbed by slip resistance and deformation. Initial buffering is performed. By the above initial cushioning, the lower end of the bumper 5 is deformed so as to come into front contact with the flat receiving surface a of the nose. Further, the bumper 5 receives a compressive force from the upper end by the surplus impact force of the striking piston 2, It is elastically deformed in the same manner as at the time to absorb the impact force of the striking piston 2 and stop the striking piston 2.

After the striking piston 2 moves up, the bumper 5 returns to its original position again due to the elastic restoring force of the projection 5b and the bumper 5 itself.

As described above, the impact piston 2 is cushioned by the bumper 5 in two stages, and the amount of deformation of the bumper 5 for cushioning is longer than in the conventional case, so that the impact noise is reduced. According to the experiment, it was confirmed that the impact noise was reduced by about 5%. In order to achieve the same level of sound reduction effect with the conventional structure, a bumper with double the volume is required. However, the deformation due to the initial buffering is the deformation along the tapered receiving surface b, which means that the bumper is deformed inward, and the amount of deformation in the vertical direction is small. Therefore, the stop position of the piston 2 by the bumper 5 is almost the same as the conventional one, and the driving force is stably maintained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an essential part of a shock absorbing device for a nailing machine according to the present invention.

FIG. 2 is an explanatory view of a shock absorbing mode by the shock absorbing device.

FIG. 3 is an explanatory view of a shock absorbing mode by the shock absorbing device.

[Explanation of symbols]

 a flat receiving surface b tapered receiving surface 1 striking cylinder 2 striking piston 4 nose portion 5 bumper 5b protrusion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Yasuhiro Naito 6-6 Hakozakicho, Nihombashi, Chuo-ku, Tokyo Max Co., Ltd.

Claims (2)

[Scope of utility model registration request] 1. A striking cylinder slidably accommodating a striking piston for striking a nail, and guiding the sliding of a driver extending below the striking cylinder and integrally connected to the striking piston, and the nail. And a nose portion that accommodates a bumper that receives a striking piston at the time of striking at the upper end of the nose portion, wherein the receiving surface that receives the lower surface of the bumper is formed into a flat shape, A tapered receiving surface is continuously formed outside the receiving surface, the lower end outer peripheral portion of the bumper is supported by the tapered receiving surface, and a gap is provided between the lower surface of the bumper and the flat receiving surface. A shock absorber for a nailer characterized by being supported. 2. The impact of a nailing machine according to claim 1, wherein a projection protruding from a lower surface of the bumper is formed, and the projection is brought into contact with the flat receiving surface to support the bumper. Shock absorber.