JPH11309681A - Dust prevention mechanism of hydraulic breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the invasion of dust inside the blow mechanism of a hydraulic breaker and also lengthen the life of the dust prevention mechanism without the deterioration of an environment and save the labour of maintenance, under the environment with lots of muddy water, earth and sand and dust such as tunnel excavation. SOLUTION: In this hydraulic breaker, a blow piston is slided in a cylinder movably forward/backward and a graver 6 is inserted in a front cap 4 fixed in front of the cylinder slidably in front/back sides by a prescribed distance. A dust cap 5 is mounted on the tip of the front cap 4 and a dust sleeve 10 is loosely fitted on the inscribed surface with the graver 6 in the dust cap 5 and in the dust sleeve 10, lubricant grooves 11, 12 for lubricant sump are formed on the inscribed surface with the graver 6 and a lubricant sump 13 blocked by the dust seals 14, 15 is provided between the dust cap 5 and dust sleeve 10 and the communication routes 11a, 12a for communicating the lubricant grooves 11, 12 with the lubricant sump 13 are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dustproof mechanism for a hydraulic breaker used for crushing rocks, concrete and the like.

[0002]

2. Description of the Related Art Conventionally, a hydraulic breaker for crushing rocks, concrete, etc. is sometimes used in an environment where there is a lot of muddy water, earth and sand, and dust. Muddy water, earth and sand, dust, etc. sometimes entered from between. In particular, in tunnel construction using a hydraulic breaker horizontally or upward, such a phenomenon is remarkable, and various attempts have been made to take countermeasures. For example, Japanese Utility Model Laid-Open No. 6-42082 discloses a hydraulic breaker in which a striking piston is slidably fitted in a cylinder so as to be able to move forward and backward, and a chisel is slidably inserted into a front head fixed to the front of the cylinder so as to be able to slide forward and backward by a predetermined distance. A bearing portion for holding the chisel on the same axis as the striking piston is provided on the front head, and packings are provided at two locations in front of the bearing portion so as to be separated from each other by a distance equal to or greater than a sliding distance of the chisel. Discloses a dustproof mechanism of a hydraulic breaker, wherein a lubricating space is formed between both packings and an injection hole for injecting a lubricant is provided in the lubricating space.

[0003] Japanese Utility Model Publication No. Hei 7-23177 discloses a dust seal for sealing a gap between a chisel and the bush by pressing the bush in which the chisel is inserted into a part of the outer peripheral surface of the chisel over substantially the entire circumference thereof. And a pressing means for pressing the dust seal concentrically and pressing the dust seal against the chisel are disclosed.

Further, Japanese Utility Model Publication No. Hei 7-23178 discloses that both ends of each pin hole provided in a front cap having a through hole formed in a vertically penetrating shape and communicated with the through hole are closed at both ends. Each of the closing plugs to be fitted is inserted into a bush in which a chisel is inserted by being inserted into a tip of the through hole, and is elastically deformable and circumscribes the chisel to seal a gap between the chisel and the bush. A dust seal is attached, and an air supply hole is provided near the base end of the front cap and communicated with an internal air chamber near the base end, and an air filter disposed at a position distant from the air supply hole and the breaker body. And a check valve for unidirectionally flowing air, which has been filtered by the air filter and introduced into the air supply line, into the air chamber, is provided in the middle of the air supply line connecting the air supply line. Dustproof device is disclosed in the hydraulic breaker.

[0005]

However, the above-mentioned dust-proof structure of the conventional hydraulic breaker has the following problems. In the hydraulic breaker disclosed in Japanese Utility Model Application Laid-Open No. 6-42082, the packing for dust prevention is always in contact with the chisel, so that there is a problem that the packing is easily worn or damaged due to the reciprocating operation or the twisting operation of the chisel. Also, the hydraulic breaker described in Japanese Utility Model Publication No. 7-23177 has an excellent dust-proof function, but it is necessary to press the chisel when the dust seal is worn. There is a problem that the property is poor and it takes time. Furthermore, 7-2
The hydraulic breaker in No. 3178 blows out air from the tip of the front cap, causing dust to fly up. In the case of construction inside a tunnel, the work environment is degraded and a compressor for blowing air is required. There was a problem that it was not suitable for use within.

The present invention has been made in view of the above-mentioned problem of the conventional hydraulic breaker. In an environment where there is a lot of muddy water, earth and sand, and dust, such as in tunnel excavation, dust and the like enter the inside of the hitting mechanism of the hydraulic breaker. The present invention is to provide a dustproof mechanism of a hydraulic breaker that prevents dust, does not deteriorate the environment, and has a long life span of the dustproof mechanism and requires no maintenance.

[0007]

According to the present invention, in order to solve such a problem, a striking piston is slidably fitted in a cylinder so as to be able to move forward and backward, and is hung in a front cap fixedly provided in front of the cylinder. In a hydraulic breaker fitted with a slidable back and forth for a predetermined distance, a dust cap is mounted in front of the front cap, and a recess is formed in an inscribed surface of the dust cap with the chisel to play the dust sleeve. Fit
In the dust sleeve, a lubricating oil groove for a lubricating oil reservoir is formed on an inscribed surface with the chisel, and a lubricating oil reservoir closed with a dust seal is provided between the dust cap and the dust sleeve, A communication passage is formed to communicate the lubricating oil groove with the lubricating oil reservoir. A grease nipple for supplying lubricating oil to the lubricating oil reservoir is attached to the dust cap.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a front portion of a hydraulic breaker showing a dustproof mechanism of the hydraulic breaker according to the present invention, and FIG.
FIG. 3 is an enlarged sectional view of a main part showing a dustproof mechanism of the hydraulic breaker of FIG.
FIG. 4 is an enlarged sectional view of a main part of the hydraulic breaker of FIG. 1 showing a twisted state of a chisel, and FIG. 4 is an exploded perspective view of a main part of the hydraulic breaker of FIG.

As shown in FIG. 1, in a hydraulic breaker A according to the present invention, a hitting piston 2 is slidably fitted in a cylinder 1 to constitute a known hydraulic hitting mechanism. When the pressure oil is supplied to the cylinder 1, the striking piston 2 can move back and forth. A front cap 4 is attached to the front of the cylinder 1, and a dust cap 5 is attached to the front end of the front cap 4. It is inserted in.

A front bush 7 is fitted in front of the inner peripheral surface of the front cap 4, and a shank bush 8 is fitted in the rear.
And the striking piston 2 is protected from reaction force and impact from the chisel 6. Further, a concave portion 5a is formed on an inscribed surface of the dust cap 5 with the chisel 6.
Is formed, and a dust sleeve 10 is fitted into the concave portion 5a. Grease G as a lubricating oil is interposed between the dust sleeve 10 and the chisel 6, and the grease G is also interposed between the dust cap 5 and the dust sleeve 10 to constitute a dustproof mechanism.

As shown in FIG. 2, the dustproof mechanism has two lubricating oil grooves 11 and 12 on the inner peripheral surface of the dust sleeve 10.
The lubricating oil grooves 11 and 12 communicate with a lubricating oil reservoir 13 provided between the dust sleeve 10 and the dust cap 5 through communication passages 11a and 12a, respectively. The lubricating oil reservoir 13 is a space formed by being closed by two dust seals 14 and 15. These lubricating oil grooves 11 and 12 and the lubricating oil pool 1
3 is filled with grease G to prevent intrusion of earth and sand, muddy water and dust from the outside.

The dust sleeve 10 has an appropriate gap between the chisel 6 and the dust cap 5 so that the dust sleeve 10 can be moved back and forth, right and left, respectively, as shown in FIG. For example, even if the chisel 6 is twisted in the direction of the arrow, the dust sleeve 10 does not directly interfere with the dust cap 5. Further, as shown in FIG. 2, the positional relationship between the dust sleeve 10 and the chisel 6 is such that the chisel 6 moves by the movement amount L, and this movement causes the chisel 6 to slide with the front bush 7. The sliding part 6a that is worn can be advanced to the position X2 at maximum, but the position X2 is
The dust sleeve 10 is set so as to be at the tip of the lubricating oil groove 11 of the dust sleeve 10, and the non-sliding portion 6 b where the chisel 6 does not slide on the front bush 7 always overlaps with the dust sleeve 10. It has a great positional relationship.

As shown in FIG. 4, the dust sleeve 10 of the dustproof mechanism is formed of an annular member, and the dust sleeve 10 is moved between the inner diameter of the dust sleeve 10 and the outer diameter of the flap 6. An appropriate gap is provided to allow the grease G to intervene in this gap,
Wear is reduced. Around the dust sleeve 10, there are provided a plurality of communication paths 11a and 12a that communicate the lubricating oil grooves 11, 12 and the lubricating oil reservoir 13.

A grease nipple 9 for supplying grease G to the lubricating oil reservoir 13 is attached to the dust cap 5. The grease nipple 9 communicates with the lubricating oil sump 13, supplies grease G to the lubricating oil sump 13, and also supplies grease G to the lubricating oil grooves 11, 12 via the communication passages 11 a, 12 a. Things. Grease G is periodically supplied to the grease nipple 9 by a grease pump or the like.

In the dustproof mechanism of the hydraulic breaker A thus configured, grease G is interposed between the dust sleeve 6 and the dust sleeve 10 or between the dust sleeve 10 and the dust cap 5. It lubricates between the sleeves 10 and prevents intrusion of dust, muddy water, earth and sand from the outside. Also, even if the chisel 6 is twisted, the dust sleeve 10 can move back and forth and left and right, and the dust cap 5
Since the grease G is interposed between the dust sleeve 1 and the dust sleeve 10, no external force is directly applied to the dust sleeve 10.
Zero wear is minimized. Further, since the chisel 6 is held by the front bush 7 and the shank bush 8 mounted in the front cap 4, the sliding portion 6a on which the chisel 6 and the front bush 7 slide is worn. Since the position of the dust sleeve 10 is located at a portion where the chisel 6 also overlaps with the non-sliding portion 6b which does not slide with the front bush 7, even if the sliding portion 6a is worn, the dust sleeve 10 has a dustproof function. It does not affect.

[0016]

As described above, according to the present invention, the striking piston is slidably fitted in the cylinder so as to be able to move forward and backward, and the chisel can be slid forward and backward within a front cap fixed to the front of the cylinder. In the fitted hydraulic breaker, a dust cap is mounted in front of the front cap, a concave portion is formed in an inscribed surface of the dust cap with a chisel, and a dust sleeve is loosely fitted. A lubricating oil groove for a lubricating oil reservoir is formed on the inscribed surface with the chisel, and a lubricating oil reservoir closed with a dust seal is provided between the dust cap and the dust sleeve. Due to the formation of a communication passage that communicates with the lubricating oil reservoir, muddy water, sediment, dust, etc. can penetrate into the impact mechanism of the hydraulic breaker even in an environment with lots of muddy water, earth and sand, such as tunnel excavation. In which an excellent effect of being able to prevent.

Further, in order to prevent intrusion of dust and the like,
Since compressed air is not used, dust does not soar at a work site such as a tunnel excavation, the working environment is not deteriorated, and equipment such as a compressor for generating compressed air is not required. In addition, the dust cap is provided with a grease nipple for supplying lubricating oil to the lubricant reservoir, so that the lubricant reservoir and the lubricating oil can be supplied only by periodically supplying lubricating oil to the grease nipple with a grease pump or the like. The groove is filled with the lubricating oil, so that there is an effect that the life of the dustproof mechanism can be extended without the need for maintenance.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a front portion of a hydraulic breaker showing a dustproof mechanism of the hydraulic breaker according to the present invention.

FIG. 2 is an enlarged sectional view of a main part showing a dustproof mechanism of the hydraulic breaker of FIG.

FIG. 3 is an enlarged sectional view of a main part of the hydraulic breaker of FIG.

FIG. 4 is an exploded perspective view of a main part of the hydraulic breaker of FIG.

[Explanation of symbols]

 Reference Signs List A Hydraulic breaker G Grease 1 Cylinder 2 Striking piston 4 Front cap 5 Dust cap 5a Concave part 6 Ledge 6a Sliding part 6b Non-sliding part 7 Front bush 8 Shank bush 9 Grease nipple 10 Dust sleeve 11 Lubricating oil groove 11a Communication passage 12 lubricating oil groove 12a communication passage 13 lubricating oil reservoir 14 dust seal 15 dust seal

Claims (2)

[Claims] 1. A hydraulic breaker in which a striking piston is slidably fitted in a cylinder so as to be able to move forward and backward, and a beam is fitted in a front cap fixedly provided in front of the cylinder so as to be slidable forward and backward by a predetermined distance. A dust cap is attached to the front of the cap, a recess is formed on the inscribed surface of the dust cap with the chisel, and the dust sleeve is loosely fitted, and the dust sleeve is fitted on the inscribed surface with the chisel. Forming a lubricating oil groove for a lubricating oil reservoir, and providing a lubricating oil reservoir closed by a dust seal between the dust cap and the dust sleeve;
A dustproof mechanism for a hydraulic breaker, wherein a communication passage communicating the lubricating oil groove and the lubricating oil reservoir is formed. 2. A dustproof mechanism for a hydraulic breaker according to claim 1, wherein a grease nipple for supplying lubricating oil to said lubricating oil reservoir is attached to said dust cap.