WO2006046816A1

WO2006046816A1 - Breaker piston and rod apparatus for a excavator

Info

Publication number: WO2006046816A1
Application number: PCT/KR2005/003542
Authority: WO
Inventors: Kim Sang Gyu; Choi Ouk Ha
Original assignee: Jisan Heavy Industry Co., Ltd.
Priority date: 2004-10-28
Filing date: 2005-10-24
Publication date: 2006-05-04
Also published as: JP4551927B2; JP2007536094A

Abstract

The invention relates to a sturcture of a pistion of a hydraulic breaker for an excavator, which is able to adjust the weight of a piston and percussion energy according to the performance of an excavator, not only by possessing a means able to adjust the weight of a piston, not offering troubles in performance of noise offset of an absorber and making noise offset from a piston and a rod which are the origin of noise, but also by no making vibration and noise transmitted outwardly. The invention relates to a structure of a piston of a breaker for an excavator demolishing by means of percussion of a rod (3) with a piston (2) of a cylinder (l), wherein a space part(3a) is formed in the internal portion of a rod(3); in the space part(3a), the space part (3) is equipped with a hammering noise absorber (3b) which is comparatively low in degree of hardness and heavier special gravity than a rod material and noise is offset by the absorption of vibration and impact and by repressing the echo of a cylinder (l) following percussion.

Description

BREAKER PISTON AND ROD APPARATUS FOR A

EXCAVATOR

Technical Field

[1] The invention relates to a structure of a piston and a rod of a hydraulic breaker for an excavator. In more details, it relates to the structure of the piston and the rod of the hydraulic breaker for the excavator to adjust the weight of the piston and percussion energy according to excavator's performance, by possessing the device able to adjust the weight, especially not giving difficulty in the performance of noise reduction on an absorber, not giving noise pollution to people who reside around buildings when breaking roads and buildings in making use of the hydraulic breaker in downtown, by making a percussion noise originated from the hydraulic breaker absorbed and reduced by the absorber of the inside of the piston and the rod. Background Art

[2] Generally a hydraulic breaker attached to an excavator is used as an additional device in an excavating machine or other basic machine for purposes of breaking rock, concrete, or some other relatively hard material.

[3] A hydraulic breaker consists of a piston and a cylinder operated by means of hydraulic pressure and a rod used when breaking objects is attached to the front part of the cylinder. The piston makes a reciprocating movement by the impact of hydraulic pressure and delivers strokes to the upper part of the rod. Simultaneouly when delivering strokes with the piston, the rod is pressed against the material to be broken, whereby the rod penetrates into the objects by the impact of the strokes and the pressing and causes the objects to break.

[4] However, the percussion noise which the piston percusses the rod and the de¬ struction noise originated when the rod demolishes the objects happens while the breaker operates, and it is well known by experience that these noises are very offensive to the ear.

[5] Especially when digging roads and demolishing buildings in downtown area noises may bring popular complaints. In these cases, there have been a lot of troubles which construction time is delayed as the construction work stops. Otherwise, the building is demolished by other means or construction work may not but proceed only little by little.

[6] The structure reducing the noise of the hydraulic breaker is known from Patent

Abstracts of Japan vol.3059016. Howerver, because the cylinder is completely wrapped with a soundproof material and the heat of operation generated from the inside of the cylinder is not easily radiated out, the hydraulic fluid is carbonized and easily exhausted and the lack of hydraulic fluid causes the life time of the cylinder to shorten. And as the bracket wrapping the cylinder does not take the structure possible to be dismantled there is a disadvantage in checking or replacing the rod and the tool pin, especially there is a problem very difficult to detach the sound proofing material fixed to the outside of the cylinder. Not only as the structure wrapping the cylinder above its necessity the soundproofing material is much more needed, but also as the bracket should grow large in size there is a weak point difficult to handle by making the total weight of the breaker increase and by making the material costs rise up. Disclosure of Invention Technical Problem

[7] Taking it into consideration, the inventor has obtained the R.O.K

Patent(vol.435827) for the hydraulic breaker, which noise is reduced with a filler by absorbing, extincting and blocking the percussion noise originated when the piston percusses the rod, by injecting a filler into the inside and sealing up it after getting wholly the origin of noise of the hydraulic breaker wrapped and sealed up tight; hydrualic breaker is used for purposes of breaking rock, concrete, building and other hard meterial.

[8] This invention relates to the improvement of the registered patent, and it is the purpose of the invention to present the structure of the piston and the rod of the hydraulic breaker for an excavator, which is able to adjust the weight of the piston and the percussion energy according to an excavator's performance, possessing a means able to adjust the weight of the piston without having difficulty in the performance of noise reduction, by also getting noise absorbed from the piston and the rod that are the origin of noise and by getting the percussion noise generated when the piston percusses the rod absorbed by the internal absorber of the piston and the rod and making no the vibration and vibrating noise transmitted outside. Technical Solution

[9] The invention to accomplish the above purpose relates to the structure of the piston of the hydraulic breaker for an excavator, which the piston of the cylinder percusses the rod for demolishion, wherein the part of space is formed in the inside of the piston; the part of space is filled with a percussion noise absorber, which is greater specific gravity than the material of the piston and comparatively lower degree of hardness in order to reduce noise by repressing the vibration of the cylinder and absorbing the vibration and impact according to percussion.

Advantageous Effects

[10] The invention has the effect able to shorten the term of the construction work as the work can be done in the day time in the downtown and such noise as the breakage noise generated in breaking or the percussion nosie of both the piston and the rod is totally reduced by stopping the claim of public complaints against the noise pollution and making the absorber of the percussion noise in the piston and the rod fill in order to absorb and reduce the percussion noise after completely wrapping the origin of noise of pneumatic or hydraulic breaker used in construction sites.

[11] The invention also has the effect able to reduce the noise with no efficency of the reciprocating movement of the piston and the percussio energy dropped, coping with not only positively the change of the hydraulic fluid which makes the piston operate, but also the excavator performance, additionally possessing the abosorber adjusting means able to effectively adjust the weight of the percussion noise absorber of the piston. Brief Description of the Drawings

[12] Fig.l is a schematic perspective view of a hydraulic breaker of the invention.

[13] Fig.2 is a schematic devided view of a hydraulic breaker of the invention.

[14] Fig.3 is a schematic front sectional view of a hydraulic breaker of the invention.

[15] Fig.4 is a schematic sectional view of the piston of the invention.

[16] Fig.5 is a schematic sectional view showing another applied example

[17] of the piston of the invention.

[18] Fig.6 is a schematic sectional view showing another applied example of the piston of the invention.

[19] Fig.7 is a schematic sectional view of a rod of a hydraulic breaker of the invention.

Best Mode for Carrying Out the Invention

[20] Fig.1 is a perspective view of the hydraulic breaker of the invention and Fig.2 is a devided sectional view of the hydraulic breaker of the invention. The hydraulic breaker of the invention consists of the cylinder(l) and the piston (2) operated by pneumatic or hydraulic pressure and the rod percussed by the piston(2) is attached to the front side of the cylinder(l). The rod is sharp-pointed to demolish or break rock, concrete, building or other hard material.

[21] The bracket(4) to be connected with the arm of an excavator in the front and the rear of the cylinder(l) is comprised and the bracket(4) and the cylinder are fixed with numbers of the side bolt(14) between the set plate(5).

[22] The invention consists of the sealed means(8) to wrap and close the origin of noise of the cylinder(l), and the soundproof means (9) to absorb and block noise.

[23] The sealed means(8) consists of the side plate(l 1) to block the both left and right parts of the cylinder(l), the upper plate(12) to block the upper part of the cylinder(l) and the lower plate(13) to block the lower part of the cylinder(l) and the side plate(l 1) and the upper plate(12) is set at a right angle together. The ends of the side plate(l 1) and the lower plate(13) is touched each other, and the front and back parts of the side plate(l 1) is contacted with the inside part of the bracket(4).

[24] The outside parts of the cylinder(l) is wrapped with the side plate(l 1), the upper plate(12) and the lower plate, and the front and back parts of the cylinder is blocked with the bracket(4), accordingly all sides is closed. Under the condition contacted with the set plate, the side plate(l 1) is connected and fixed by the bolt(18).

[25] The soundproof means(9) is for closing the outside of the cylinder(l) wrapped by the sealing means(8) and the sound absorption plate(16) is used. The sound absorption plate(16) is made of rubber material, which has a greater specific gravity than iron, and it is formed with porosity and has the performance of sound absorption.

[26] The sound absorption plate(16) is about 10mm in thickness and it fills up the space between the sealing means(8) and the cylinder(l), putting it in several folds. Ac¬ cordingly as the noise originated from the cylinder(l) is either absorbed by the sound absorption plate(16) or collided against the sealing means (8) and is soundproofed the noise is effectively reduced.

[27] As the rod is connected with the tool pin(6) and the shank(7) not to take away from the cylinder(l) the noise is effectively absorbed and soundproofed by the sealing means(8) and the soundproof means(9) even though it is transmitted to the outside of the cylinder(l) through the surface of the shank(6).

[28] The auxiliary cover(15) wrapping the rod(3) is arranged in the the lower part of the cylinder(l). The auxiliary cover penetrates the lower plate and holds the rod(3) and in the inner part, the sound absorption plate for sound absorption and the packings for sealing are arranged in several folds. Therefore the noise leaked out of the cylinder(l) through the rod(3) is filtered and reduced by the auxiliary cover(15).

[29] Fig.3 and Fig.4 show the structure of the piston of the invention. As shown in the drawings the space(17a) is formed in the Piston(2) and it is filled with the percussion noise absorber by size fully plugging this space(17). As the percussion noise absorber(17) has a greater special gravity than iron and such materials as lead, tin and copper comparatively lower in hardness are used the vibration and the noise is offset when percussing. And owing to making the piston(2) heavierly the percussion performance is improved when the piston(2) percusses the rod(3).

[30] As the hydraulic fluid film is formed at an interval of 0.25mm between the piston(2)and the cylinder(l) it is natural that the percussion sound happened from the piston(2) is transmitted through the oil film. Accordingly the percussion noise happened when the piston(2) percusses the rod(3) is the epicenter of the main noise happened from the hydraulic breaker.

[31] According to the invention, as the inside of the pis ton (2) is equipped with the percussion noise absorber(17) the percussion noise happened when the piston(2) percusses the rod(3) is absorbed and extincted, and as the vibration and the echo do not happen the noise and the echo phenomenon transmitted to the cylinder through the hydraulic fluid film is reduced. The absorber(17) is fixed by joining the plug(17b) with the function of the nut on the upper part of the piston (2).

[32] The undescribed number 10 shows the rubber pad with cushion equipped between the set plate(5) and the bracket(4) and the number 19 shows the bracket pin to connect it with an excavator.

[33] In accordance with the invention, the assembly is shown like Fig.3 and Fig.4. The percussion noise absorber is by force pressed into the space(17a) of the piston(2) and it makes no gap between the absorber(17) and the space(17a). In case that any gap exists, as the part acts as a resonator and part of the absorber(17) and the piston(2) may be damaged the absorber(17) and the piston(2) must carefully be assembled. The bottom part of the space(17a) is machined in shape of concave circular arcs with no angles in order not to have a phenomenon inclining towards one side. The absorber(17) is sealed and fixed to the inside of the piston(2) by the plug(17b) and the absorber(17) and the piston(2) is united.

[34] The invention describes that the cylinder(l) is fixed in the bracket(4) when putting the rubber pad(lθ) with cushion between the bracket(4) and the set plate(5) and joining in use of the side bolt(14). And the sound absorbering plate(16) is layed between the front and rear braket to get the outer sides of the cylinder(l) wrapped and the steel cover(l 1) is assembled to fasten to the set plate(5) with the bolt(18), so the opened left side and right side of the cylinder(l) is veilded by the steel cover(l 1) and the sound absorbing plate(16). At this time, as the upper plate(12) on the upper part of the steel cover(l 1) is unitedly equipped the origin part of the noise of the cylinder(l) is wrapped except the lower part of the cylinder(l).

[35] The lower plate(13) is put into the lower part of the cylinder(l) and the outer side of the lower plater(13) is touched with the inner side of the bracket(4). The origin part of the noise is totally veiled and closedly assembled to insert the auxiliary cover(15) into the rod(3) and fix it to the lower plate(13).

[36] While the breaker is operated the hammering noise happens as the piston(2) re¬ ciprocates and percusses the rod(3). As the percussion noise happened at this time is mostly absorbed by the percussion noise absorber(17) equipped in the piston(2) the noise below 70dB(the living noise regulation of the Ministery of Environment, R.O.K.) only happens. The rest of the noise comes out through the outside of the tool pin(6) to hold the rod(3) and at this time, as it is absorbed and soundproofed by the absorber(lβ), the steel cover(l 1), the upper part of the steel cover(12) and the lower plate(13) the noise is effectively reduced. [37] As the noise leaked out through the rod(3) is too absorbed and reduced by the auxili ary cover of the front head and the outer packing the percussion noise of the breaker can be diminished.

[38] Fig.5 is a sectional view showing the another example of the breaker piston of the invention. Another example shows that the absorber adjusting means able to adjust the weight not having troubles in performance of the noise reduction equipped internally into the piston(2) is formed. The absorber adjusting means is to make the percussion energy and the weight of the piston(2) adjust effectively according to the performance of an excavator. In case of a large excavator because the operating pressure is high to activate the piston(2) the piston can be operated without any troubles even if the weight of the piston(2) changes, but in case of a small excavator, according to the change of the weight of the piston because the reciprocation efficiency of the piston can be changed and becomes worse the breaker performance is not fully displayed.

[39] Therefore, the absorber adjusting means (19) is formed to adjust the weight of the hammer noise absorber(17) equipped in the pistion able to reduce the noise not showing a big change in the percussion energy which the piston of the hydraulic breaker percusses the rod.

[40] The absorber adjusting measure(19) of the invention is equipped with a pipe(19a) penetrating vertically the inside of the hole to make the weight of the absorber(17) reduce and the absorber(19b) is filled to reduce the phenonmenon of echo inside the pipe(19a). The absorber is made of mixed rubber and urethane and it is used at the middle of specific gravity between the piston(2) and the absorber(17).

[41] The another example of embodiment of the invention can positively cope with the change in required oil flow to operate the pistion and an excavator erformance, and protect the reciprocation effiency of the pistion from declining as vertical penetation through the inside of the heavier asborber than the piston can reduce the weight of the pistion.

[42] As the invention makes the inside of the absorber(17) a hole, vibration may be further increased instead due to the reason why the phenomenon of echo happens. To clear it, the penetrated part of the hole in the absorber(17) is filled with the sound absorber(19b) of the absorber adjusting means(19). It protects against vibration and sound propagation because it can get rid of the phenomenon of echo.

[43] Fig.6 is a sectional drawing showing another applicable example of the the piston of hydraulic breaker of the invention and it has the same formation with another applicable example of Fig.5. There is only difference from the substance materials to be filled in the absorber adjusting means(19). The substance material to be filled in the absorber adjusting means(19) consists of vibrationproof material(19c), which protects against vibration. [44] Such particles as sand and iron powder, and fluid as grease are applied to the vibration-proof material. It protects from vibration happened while the piston percusses the rod.

[45] Fig.7 is a sectional drawing of the breaker rod of the invention and it has the same principle with the piston sturcture of the invention. It is additionally equipped with apparatus only to protect the upper part of the rod from breakage by impact happened while the piston percusses the rod and to reinforce the tip of the lower part of the rod.

[46] The rod of the invention forms the hole(3a) to be equipped with the percussion noise absorber(3b) and as the percussion noise absorber(3a) has a greater specific gravity than the material of the rod and consists of lead, tin and copper which are com¬ paratively low in degree of hardness, vibration and echo are offset while the piston(2) percusses the rod.

[47] The cap(3c) is covered in the upper part of the rod(3). As the cap(3c) slopes in shape of taper towards the joint part of the rod and the center of the cap(3c) and the rod(3) is exactly fitted exactly. They are fixed by welding or heat insertion.

[48] The tip(3d) of comparatively higher alloyed steel in strength and wear resistance than the rod(3) is arranged in the lower part of the rod(3). The tip(3d) also slopes in shape of taper towards the joint part of the rod and they are fixed by welding or heat insertion.

[49] As the rod of the invention formed as above is equipped with the absorber(3b) the percussion noise and echo of vibration happened while the piston(2) percusses the rod is offset. Especially as the piston(2) is also equipped with the absorber(17) the in¬ teraction of these absorbers(17),(3b) has an effect on reducing the percussion noise, and as in the upper part of the rod(3) the cap(3c) to protect the against the breakage of the rod according to percussion of the piston(2) is formed the trustability of the product get improved. And the changeable tip(3d) is formed in the lower part of the rod(3). If the tip is only replaced the rod can continue to use, so replacement expenses can be cut down.

Claims

[1] A structure of the piston of the hydraulic breaker for an excavator comprising that the noise is reduced by repressing the echo of the cylinder(l) and absorbing the vibration and impact according to percussion equipped with the percussion noise absorber(17), which is heavier than the piston(2) and comparatively low in degree of hardness in the space part, which is formed inside of the piston in the piston structure of the hydraulic breaker for excavator demolishing by percussion of the rod(3) with the piston(2) of the cylinder(l).

[2] A structure of the piston of the hydraulic breaker for an excavator according to claim 1, wherein the percussion noise absorber(17) is made of one of lead or tin.

[3] A structure of the piston of the hydraulic breaker for an excavator according to claim 1, wherein the percussion noise absorber(17) does not offer troubles in the performance of the noise offset, but is equipped with the absorber adjusting means(19) able to adjust the weight.

[4] A structure of the pistion of the hydraulic breaker for an excavator according to claim 3, wherein the absorber adjusting means(19) is equipped with the pipi(19a) penetrating the absorber(17) into the space part of the hole; in the pipe(19a), the pipe(19a) is filled with one of either the sound absorption material(19b) reducing the vibration noise according to echo or the vibrationproof material(19c) protecting vibration according to echo.

[5] A structure of the rod of the hydraulic breaker for an excavator demolishing by means of percussion of the rod(3) with the piston(2) of the cylinder(l), wherein the space part(3a) is formed in the internal portion of the rod(3); in the space part(3a), the space part(3) is equipped with the percussion noise absorber(3b) which is comparatively low in degree of hardness and heavier special gravity than the rod material and the noise is offset by the absorption of vibration and impact and by repressing the echo of the cylinder(l) following percussion.

[6] A structure of the rod of the hydraulic breaker for an excavator according to claim 5, wherein the upper part of the rod(3) is joined with the cap(3c) which seals the percussion noise absorber(3b) to protect it from breakage according to percussion of the piston and the lower part of the rod(3) is joined with the re¬ placeable tip(3d) which is high in strength and abrasion resistance.