JP3019178U - Chisel for hydraulic breaker - Google Patents

Abstract

(57) [Summary] [Object] With regard to a hydraulic breaker chisel, an object thereof is to provide a chisel for a hydraulic breaker capable of reducing noise and having a long life. [Structure] An elastic body 3 and a cover 4 for tightening the elastic body 3 are provided around a portion of a chisel main body 2 located near the breaker body 1 when the elastic body 3 is mounted on the breaker body 1.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a hydraulic breaker chisel, and more particularly to a hydraulic breaker chisel that can reduce noise emission and have a long life.

[0002]

[Prior art]

 Nowadays, when social demands for pollution prevention are becoming stronger, noise is regarded as the most common pollution, and it is required to constantly reduce noise from the viewpoint of pollution prevention. Therefore, it is desirable to reduce noise.

In the civil engineering and crushing industries, hydraulic breakers have been widely used instead of air hammer type breakers from the viewpoint of preventing pollution and improving working environment. However, it is still required to reduce noise even when using a hydraulic breaker. There have been no studies or proposals to reduce the noise of hydraulic breakers.For example, the sources of noise associated with breaker work are roughly divided into breaker bodies, brackets, chisels, and crushed objects. Among them, it is known that the noise from the chisel occupies as much weight as the noise from the bracket and also contains a high frequency component that is offensive to the ears.

Further, as a means for reducing the noise from the chisel, it has been proposed to add a device to the structure of the breaker body, as shown in Japanese Utility Model Publication No. 63-205 52, for example. However, in this type of proposal, the structure of the breaker body is more or less complicated, and the weight is often heavy. Therefore, the workability is often deteriorated. Another means to reduce the noise from the chisel is to add some innovation to the chisel structure. For example, as disclosed in Japanese Utility Model Publication No. 56-23019, a chisel in which almost the entire portion of the chisel protruding from the breaker body is covered with an elastic body and a steel cover (hereinafter referred to as Conventional Example 1). For example, as disclosed in Japanese Patent Publication No. 55-4555, a chisel (hereinafter referred to as Conventional Example 2) covered with a metal having a large transmission loss, such as lead, and a metal having abrasion resistance (hereinafter referred to as Conventional Example 2). Take as an example.

[0005]

[Problems to be solved by the device]

 However, in the above-mentioned conventional example 1, since the entire chisel portion projecting from the breaker body is covered with the elastic body and the steel cover, it is difficult to use because it has a large restriction on the work. Also, if the parts protruding from these are worn out, they will reach the end of their life, so they must be replaced in a short time, which is not practical in view of the cost of construction.

Further, also in the above-mentioned conventional example 2, the portion of the chisel covered with a metal having a large transmission loss and a metal having wear resistance must be made considerably large, which results in a very high cost and a damping effect. Is small, and if the drill rock at the tip wears out, it will reach the end of its life. Therefore, it must be replaced in a short time, which is not practical in consideration of construction cost.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a chisel for a hydraulic breaker that can reduce noise emission and have a long life.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the chisel of the present invention is provided with an elastic body and a cover for tightening the elastic body around the part of the chisel body located near the breaker body when mounted on the hydraulic breaker body. It is characterized by

[0009]

[Action]

 In the present invention, the elastic body is not limited as long as it has elasticity, and examples thereof include steel, metal such as phosphor bronze, and natural or synthetic rubber. Among these, absorption of high-frequency vibration is mentioned. It is preferable to use a rubber having a high ability. The elastic body may have any shape as long as it surrounds the chisel, and may be continuous in the entire circumferential direction or divided in the circumferential direction. Also, the shape of the inner peripheral surface of the elastic body does not have to correspond to the outer peripheral surface of the chisel, but in order to increase the vibration transmission area and evenly transmit the vibration over the entire circumference, It is preferable to correspond to the outer peripheral surface. Further, the outer peripheral surface of the elastic body may be a cylindrical peripheral surface having an equal diameter, or a cylindrical peripheral surface having a different diameter such as a one-flow tapered peripheral surface or a double-flow tapered peripheral surface.

The elastic body may be fixed to the chisel by adhesion such as vulcanization adhesion, fusion, welding, or the like, but it can be fixed to the chisel by a frictional force generated as a result of tightening by the cover. The cover may be configured so that the elastic body is fastened to the chisel. For example, the cover is formed into a ring shape having a central hole smaller than the outer diameter of the elastic body in a natural state, and the elastic body fitted to the chisel in the central hole. The elastic body can be configured to be fastened to the chisel by pushing the into the central hole.

The cover may be configured to locally tighten the elastic body, but in order to eliminate local fatigue of the elastic body due to stress concentration, the cover is configured to be uniformly tightened over the entire circumference. Preferably. In the present invention, by tightening the elastic body on the chisel, the vibration of the chisel is absorbed by the elastic body and a part of the vibration is transmitted to the cover to vibrate the cover. The energy of the vibration is attenuated by interfering with the vibration of the cover and the vibration of the chisel, and the elastic body and the cover act as a dynamic damper (dynamic damper) to suppress the vibration of the chisel.

Also, in the present invention, the elastic body and the cover are provided around the portion located near the breaker body when mounted on the hydraulic breaker body, so that the wear of the chisel reaches until the vicinity of the breaker body. You can continue to use the book chisel. In the present invention, in particular, when a pressing board that is inserted between the breaker body and the cover and has elasticity longer than the distance between the breaker body and the cover in a free state is provided, use a long pressing board. Since the elastic body is compressed in the axial direction by pressing the chisel while sandwiching it, the radial tightening force of the chisel by the elastic body is further strengthened, and the damping effect is increased.

Further, the damping effect of the chisel can be maintained for a long period of time by exchanging the pressing board as needed. The movement of the chisel with respect to the breaker body is elastically limited by the elastic force of the pressing board, and the generation of unnecessary vibration of the chisel is suppressed.

[0014]

【Example】

 The present invention will be described in detail below based on specific embodiments shown in the accompanying drawings. As shown in the partially cutaway front view of FIG. 1, the chisel body 2 attached to the lower part of the breaker body 1 has an elastic body 3 around the portion located near the breaker body 1 when the body is attached to the breaker body 1. And a cover 4 for tightening the elastic body 3.

In order to limit the movement of the elastic body 3 and the cover 4 to the tip end side of the chisel body 2, the chisel body 2 is provided with an inner peripheral portion of the elastic body 3 at a predetermined height as necessary. A brim 5 is formed to be received from below. The elastic body 3 may be made of an elastic material, and may be made of steel, a metal such as phosphor bronze, or a natural or synthetic rubber. In this embodiment, the elastic coefficient is adjusted. The urethane rubber is used because it can be easily adjusted by adjusting the degree of polymerization and the degree of absorption of high frequency vibrations. The length of the elastic body 3 is about 1.5 to 2.5 times the diameter of the chisel body 2 for effective damping.

Further, the elastic body 3 may have any shape as long as it surrounds the periphery of the chisel body 2, and may be divided into a plurality of pieces in the circumferential direction. However, in this embodiment, the number of parts is minimized. In order to reduce the number, as shown in the cross-sectional view of FIG. 2, it is formed into a single cylindrical shape that is continuous in the entire circumferential direction. Further, the shape of the inner peripheral surface of the elastic body 3 does not have to correspond to the outer peripheral surface of the chisel body 2, but the vibration transmission area is increased and the chisel body 2 and the elastic body 3 are evenly distributed over the entire circumference. The outer surface of the chisel main body 2 is made to correspond to the transmission of vibrations to and from the chisel body 3.

In addition, the outer peripheral surface of the elastic body 3 may be a cylindrical peripheral surface having a different diameter, such as a single-flow tapered peripheral surface or a double-flow tapered peripheral surface. In order to improve the workability, it is formed on the cylindrical surface of equal diameter. The elastic body 3 may be fixed to the chisel body 2 by, for example, adhesion such as vulcanization adhesion, fusion bonding, welding, etc. However, since the number of processing steps is minimized to reduce the processing cost, this In the embodiment, the elastic body 3 is tightened by the cover 4 to be described later, or the elastic body 3 is tightened by the elastic force of the elastic body 3 in addition to the tightening of the cover 4 by the frictional force. Is fixed to the chisel body 2.

The cover 4 needs to be configured so as to exert the action of fastening the elastic body 3 to the chisel body 2, and is made of, for example, iron, steel, copper, aluminum, lead, or a main component thereof. It is made of a material having higher rigidity than the elastic body 3, such as an alloy. The cover 4 may be configured so that the elastic body 3 is fastened to the chisel body 2. In this embodiment, the cover 4 has a ring shape having a central hole 6 smaller than the outer diameter of the elastic body 3 in a natural state. The elastic body 3 is formed, and the elastic body 3 fitted onto the chisel body 2 is pushed into the center hole 6 so that the elastic body 3 is fastened to the chisel body 2.

Further, the cover 4 may be configured to locally tighten the elastic body 3 to the chisel main body 2 by forming irregularities on the peripheral surface of the center hole 6, for example, but in this embodiment, In order to eliminate the local fatigue of the elastic body 3 due to the stress concentration on the tightened portion, the elastic body 3 is configured to be uniformly tightened over the entire circumference. In addition, an inner flange 7 that is received on the upper surface of the elastic body 3 is provided above the cover 4 so that the elastic body 3 and the cover 4 can be easily pushed.

In the present embodiment, by tightening the elastic body 3 on the chisel body 2, vibration of the chisel body 2, particularly high-frequency vibration that causes annoying noise is absorbed by the elastic body 3 and the elastic body 3 is absorbed. 3 and the cover 4 act as a dynamic damper. That is, a part of the vibration mainly consisting of low-frequency vibration is transmitted to the cover 4 and the cover vibrates, and the vibration of the cover 4 and the vibration of the chisel body 2 interfere with each other to attenuate the vibration energy and It reduces the dissipation of vibrations from the body 2.

The high-frequency vibration absorbing action of the elastic body 3 and the dynamic damper action of the elastic body 3 and the cover 4 are combined to reduce the work noise by about 2 to 3 dB more than the noise countermeasure of the bracket alone. It was possible to achieve noise reduction of about 11 to 15 dB. Further, in this embodiment, since the elastic body 3 and the cover 4 are provided around the portion located near the breaker body 1 when the elastic body 3 and the cover 4 are mounted on the breaker body 1, the life of the chisel body 2 is extended and the chisel body 2 is extended. One chisel body 2 can be used continuously until the wear of the body 2 reaches the vicinity of the breaker body 1.

In the above-described embodiment, the cover 4 is integrally formed. However, as shown in the cross-sectional view of FIG. 3, the cover 4 is divided into a plurality of pieces (here, two pieces) in the circumferential direction. It does not prevent the parts of the structure from being deformed to be connected by bolts 8. In the case where the cover 4 is divided and formed so as to be fastened by the bolts 8, the elastic coefficient of the elastic body 3 is adjusted to the optimum value that can reduce the noise most depending on the tightening condition of the bolts 8. be able to.

Further, in the above-described embodiment, the elastic body 3 is formed in a cylindrical shape. However, as shown in the half sectional view of FIG. 4, the elastic body 3 has the chisel body 2 on the inner peripheral portion thereof. It has a bulged portion 10 and a recessed groove 11 formed at a certain pitch in the axial direction, and a recessed groove 12 is formed in the outer peripheral portion at a portion corresponding to the bulged portion 10 in the inner peripheral portion. By forming the bellows tube shape having the bulged portions 13 at the portions corresponding to the recessed grooves 11 in the peripheral portion, the vibration absorbing ability of the elastic body 3, especially the high frequency vibration absorbing ability can be enhanced.

Further, in the above-described embodiment, as shown in the half sectional view of FIG. 5, for example, a small diameter portion 9 is formed in a part of the chisel body 2 on the upper side of the collar 5, and the inner peripheral portion of the elastic body 3 is formed. It is also possible to receive the upper edge on the stepped-down surface of the small-diameter portion 9. When forming the small-diameter portion 9 as described above, the elastic body 3 is not prevented from being formed as an integrally continuous body in the circumferential direction, but in order to facilitate the assembly of the elastic body 3, for example, as shown in FIG. It is advantageous to divide and form a plurality of elastic bodies 3 (two here) in the circumferential direction, as shown in the respective cross-sectional plan views.

Further, in this case, the cover 3 is divided into a plurality of pieces (here, two pieces) in the circumferential direction as shown in FIG. 7, even if the cover 3 is an integrally formed article continuous in the circumferential direction as shown in FIG. They may be formed and connected by the bolt 8. When the small diameter portion 9 is formed on the chisel body 2 as described above, the elastic body 3 and the cover 4 can be made small in diameter to reduce the size and weight of the chisel body 2 as a whole.

In a chisel for a hydraulic breaker according to another embodiment of the present invention, as shown in the half sectional view of FIG. 8, for example, in the above embodiment, a free state is provided between the cover 4 and the breaker body 1. Then, the pressing plate 14 having elasticity longer than the distance between the breaker body 1 and the cover 4 is inserted. As a result, the movement of the chisel with respect to the breaker body is elastically limited by the resilience of the pressing board 14, so that unnecessary vibration of the chisel body 2 itself is suppressed, and the noise level of the breaker work is reduced to the above-mentioned one embodiment. It was possible to further reduce the noise by about 1 dB, and it was possible to reduce noise by about 15 to 16 dB. In addition, since the elastic body is axially compressed by pressing the chisel with a long pressing board sandwiched between them, the radial tightening force of the chisel by the elastic body is further strengthened, and the vibration damping effect is increased.

Further, in FIG. 9, the collar 5 of the chisel body 2 is omitted, a small-diameter portion 9 is formed in the chisel body 2, and the elastic body 3 is fitted into the small-diameter portion 9, whereby the axial center of the elastic body 3 is reduced. I try to decide the position in the direction. Other structures, operations and effects of this embodiment are essentially the same as those of the above-mentioned one embodiment or its modification, and therefore their explanation is omitted to avoid duplication.

In yet another embodiment of the present invention shown in the front view, which is a half section of FIG. 10, the outer peripheral surface of the elastic body 3 and the corresponding inner peripheral surface of the center hole 6 of the cover 4 are tapered peripheral surfaces which spread downward. It is formed in. In this case, the elastic body 3 can be easily pushed into the cover 4, and the elastic body 4 can be more strongly pressed against the chisel body 2 and the elastic coefficient of the elastic body 3 can be increased. It can absorb energy.

Other configurations, operations and effects of this embodiment are the same as those of the above-mentioned one embodiment, and therefore their explanations are omitted to avoid duplication. In this embodiment, a small diameter portion 9 is formed in the chisel body 2 in place of the collar 5 as shown in each of the half cut front views of FIG. 11 or 13, or, for example, the half cut front view of FIG. As shown in, there is no hindrance to inserting the pressing plate 14 between the breaker body 1 and the cover 4.

In still another embodiment of the present invention shown in the partially cutaway front view of FIG. 14, the collar 5 of the chisel body 2 and the inner collar 7 of the cover 4 of each of the above embodiments are omitted and the cover 4 is contacted. The elastic body 3 is fastened to the chisel body 2 by externally fitting the elastic body 3 in the fitted state and pressing the cover 4 in the radial direction by a press to reduce the diameter. In this embodiment, the displacement of the elastic body 3 is prevented exclusively by the frictional force between the chisel body 2 and the elastic body 3, and the displacement of the cover 4 is exclusively prevented by the frictional force between the elastic body 3 and the cover 4. To be prevented.

In this embodiment, since the shapes of all the parts are simplified, the manufacturing cost thereof can be reduced, and the elastic coefficient of the elastic body 3 can be increased by tightening the press. Therefore, the elastic body 3 can absorb large vibration energy. Other configurations, operations and effects of this embodiment are the same as those of the above-mentioned one embodiment, and therefore their explanation is omitted to avoid duplication.

Also in this embodiment, for example, as shown in the partially cut front view of FIG. 15, a small-diameter portion 9 is formed in the chisel body 2, and the elastic body 3 is fitted into the small-diameter portion 9. It does not hinder the shaping or inserting the pressing board 14 between the breaker body 1 and the cover 4 as shown in the front view of FIG. Further, by providing a detent for preventing relative displacement between the elastic body and the cover and between the elastic body and the chisel, wear of the elastic body due to microvibration can be prevented and durability is improved.

[0033]

[Effect of device]

 As described above, according to the present invention, the elastic body and the cover for tightening the elastic body are provided around the portion of the chisel body located near the breaker body when mounted on the breaker body. While part of the vibration is absorbed by the elastic body, the vibration of the chisel body is damped by the dynamic damper action of the elastic body and the cover, and the noise of the breaker work is further reduced by 2-3 dB compared to the noise countermeasure of the bracket only. Therefore, it can be reduced by about 11 to 15 dB.

Further, since the elastic body and the cover are provided around the portion of the chisel body located near the breaker body when mounted on the breaker body, until the abrasion of the chisel body reaches near the elastic body and the cover. You can continue to use one chisel body, and the life of the chisel body will be longer than in the conventional example. Further, in the present invention, the chisel is not covered with the elastic body and the steel cover almost entirely, and the base end side of the chisel may be attached with an elastic body having a diameter of 1.5 to 2.5 times. There are few restrictions on the above.

In the present invention, in particular, when a pressing board which is inserted between the breaker body and the cover and has elasticity longer than the distance between the breaker body and the cover in the free state is provided, the breaker of the chisel is used. Since the movement of the main body is elastically limited by the elastic force of the pressing board, and the generation of unnecessary vibration of the chisel itself is suppressed, the noise level of the breaker work is reduced by 11 to 15 dB by adding the pressing board, and it is further reduced by 1 dB. It can be reduced by about 12 to 16 dB. Since the elastic body is axially compressed by pressing the chisel while sandwiching a long pressing plate, the radial tightening force of the chisel by the elastic body is further strengthened, and the vibration damping effect is increased.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of an embodiment of the present invention.

FIG. 2 is a cross-sectional plan view taken along the line AA of FIG.

FIG. 3 is a cross-sectional plan view showing a modification of the cover according to the embodiment of the present invention.

FIG. 4 is a semi-sectional front view showing a modified example of the elastic body of the embodiment of the present invention.

FIG. 5 is a front view, partially cut away, showing a modification of the chisel body according to the embodiment of the present invention.

FIG. 6 is a cross-sectional plan view showing another modification of the elastic body according to the embodiment of the present invention.

FIG. 7 is a cross-sectional plan view of another modification of the embodiment of the present invention.

FIG. 8 is a partially cutaway front view of another embodiment of the present invention.

FIG. 9 is a partially cutaway front view of another embodiment of the present invention.

FIG. 10 is a partially cutaway front view of another embodiment of the present invention.

FIG. 11 is a partially cutaway front view of a modified example of still another embodiment of the present invention.

FIG. 12 is a partially cutaway front view of another modification of the other embodiment of the present invention.

FIG. 13 is a semi-sectional front view of still another modification of the other embodiment of the present invention.

FIG. 14 is a partially cutaway front view of still another embodiment of the present invention.

FIG. 15 is a partially cutaway front view of a modified example of still another embodiment of the present invention.

FIG. 16 is a semi-sectional front view of another modification of yet another embodiment of the present invention.

[Explanation of symbols]

 1 ... Breaker body 2 ... Chisel body 3 ... Elastic body 4 ... Cover 14 ... Pressing board

Claims (2)

[Scope of utility model registration request] 1. A chisel for a hydraulic breaker, characterized in that an elastic body and a cover for tightening the elastic body are provided around a portion of the chisel body located near the breaker body when mounted on the breaker body. 2. The chisel for a hydraulic breaker according to claim 1, further comprising a pressing plate which is inserted between the breaker body and the cover and has elasticity longer than a distance between the breaker body and the cover in a free state. .