WO2007000899A1

WO2007000899A1 - Breaker

Info

Publication number: WO2007000899A1
Application number: PCT/JP2006/312005
Authority: WO
Inventors: Shigeru Miyakawa
Original assignee: Yamada Machinery Industrial Co., Ltd.
Priority date: 2005-06-28
Filing date: 2006-06-15
Publication date: 2007-01-04
Also published as: JP2007007738A

Abstract

A breaker (1), comprising a cylinder (8) reciprocatingly driven in a body (2) and having a lower opening and a piston (12) movable in the cylinder (8) and having a hammering bar (13) projected from the opening of the cylinder (8). A hammering tool support part (26) and a hammering tool (18) detachable from the support part (26) are fitted to the lower part of the body (2). The hammering tool (18) comprises an upper shank part (18a), an intermediate flange (18b), and a lower working part (18c). The support part (26) comprises a guide part (31) holding a part of the shank part (18a) and a cup part (29a) put on the upper end of the shank part (18a) and receiving a hammering by the hammering bar (13). A vertically movable intermediate member (29) is installed in the body (2). A stopper (33) allowed to select the state of being interfered with the flange or the state of being not interfered with the flange is fitted to the lower side of the intermediate flange (18b).

Description

Specification

Breaker

Technical field

TECHNICAL FIELD [0001] The present invention relates to a breaker used for crushing solid materials such as concrete or hardened phenolate at road construction sites or construction sites.

Background art

[0002] A breaker of the above type usually has a striking tool supported at the lower part of the main body so as to be reciprocally movable in the vertical direction. An impact force is applied to the hitting tool by hitting the head of the hitting tool with a hammer that is driven back and forth by a mechanical reciprocating drive mechanism or the like. For example, in the breaker described in Patent Document 1 below, the movable cylinder is reciprocated by a crank mechanism that does not directly reciprocate the hammer body. A free piston is inserted into the movable cylinder, and a function as a hammer body for hitting a striking tool supported by the free piston at the lower part of the machine body is provided. The free piston divides the internal space of the movable cylinder into an upper pneumatic chamber and a lower pneumatic chamber, and has a striking rod integrally formed so as to protrude below the lower opening force of the movable cylinder. .

[0003] When the movable cylinder is reciprocated, the free piston is reciprocated so as to alternately compress the lower air pressure chamber and the upper air pressure chamber by inertial force. As the speed of the reciprocating motion of the movable cylinder increases, the lower air pressure chamber and the upper air pressure chamber are compressed more greatly. When the movable piston attempts to move down through top dead center, the upper pressure chamber is compressed most. The compressed pneumatic chamber expands like an air panel and tries to lower the free piston at high speed. The free piston moves at a very high speed due to the synergism between the downward movement of the movable cylinder and the expansion of the upper air pressure chamber. By hitting the hitting tool against the head of the hitting tool before the movable cylinder reaches the bottom dead center and compression of the lower pneumatic chamber starts, the hitting rod of the free piston moves down the hitting tool at a very high speed. You can hit it.

[0004] On the other hand, such a breaker reduces weight and outer dimensions while maintaining a certain level of performance. The power to do is required. The breaker described in Patent Document 1 is provided with a dedicated hitting tool to reduce the vertical height of the entire device.

[0005] However, the hitting tool is a consumable product, and its tip is worn or damaged by relatively short-term use. Therefore, it is disadvantageous for the user in terms of availability or cost to require a dedicated tool for hitting.

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 64-2878

Disclosure of the invention

[0007] The present invention has been conceived under the above circumstances, and makes it possible to use an easily available commercially available hitting tool while maintaining the crushing performance of the breaker. It is an object of the present invention to provide a breaker that can be easily replaced.

[0008] In order to solve the above problems, the present invention employs the following technical means.

[0009] That is, the breaker of the present invention is reciprocally driven in the vertical direction inside the main body, and has a movable cylinder having a lower opening, and is inserted into the movable cylinder so as to be movable in the vertical direction. A breaker comprising a free piston having a striking rod projecting from the opening at the bottom, a striking tool support provided at the bottom of the main body, and a striking tool removably supported by the striking tool support. The hitting tool includes an upper shank portion, an intermediate flange, and a lower working portion, and the hitting tool support portion holds a part of the upper shank portion of the hitting tool in the axial direction. A guide part and a cup part that covers the upper end of the upper shank part of the hitting tool and has an upper surface that receives a hit by the hitting rod of the free piston and the inside of the main body The intermediate member that is guided so as to be movable in the up-and-down direction, and the state that does not interfere with the state that interferes with the intermediate flange and the intermediate flange that moves downward from the intermediate flange of the hitting tool. And a stagger that can be selected.

[0010] The hitting tool has its upper shank portion supported by the guide portion and the intermediate member placed on the upper shank portion so as to be stably movable in the vertical direction. The striking force from the striking rod of the free piston is transmitted to the striking tool via the intermediate member. By forming this intermediate part by selecting a material that can withstand the impact of the free piston force, even if a commercially available hitting tool is used, the upper shank part of the hitting tool is protected and Life can be extended. The hitting tool can be easily replaced by operating the stopper.

Preferably, the intermediate member has an outward flange portion at a lower end of the cup portion, and an outer periphery of the outward flange portion is guided in the vertical direction by the inner wall of the main body. Further, a lower end of a coil panel for biasing the intermediate member downward is brought into contact with an upper surface of the outward flange portion of the intermediate member.

[0012] With this configuration, even when the hitting tool is urged downward by the coil spring via the intermediate member, the vertical dimension of the device is suppressed as much as possible. can do.

[0013] Preferably, an elastic member supported by the main body is disposed below the outward flange portion of the intermediate member.

[0014] By configuring in this way, it is possible to absorb the impact conveniently and prevent damage to the apparatus even in the idle driving state.

[0015] Preferably, the stopper is configured to be operated by a lever.

[0016] By configuring in this way, the hammering tool can be replaced more easily.

[0017] Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

Brief Description of Drawings

FIG. 1 is a longitudinal sectional view of an embodiment of a breaker of the present invention.

FIG. 2 is an enlarged view of the main part of FIG.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

[0020] As shown in Fig. 1, the breaker 1 of the present embodiment is a so-called portable engine breaker equipped with a small gasoline engine. A gasoline engine 3 is installed. A fixed cylinder cylinder 5 is inserted inside the cylindrical outer shell 4 constituting the upper part of the cylindrical main body 2 so as to be double with respect to the cylindrical outer shell 4. Is a cylinder that is continuous with the upper crank chamber 6 Space 7 is formed.

[0021] A movable cylinder 8 is fitted in the fixed cylinder cylinder 5 so as to be slidable up and down in the axial direction of the main body 2. The bracket 8 is assembled in the crank chamber 6. The rotating disc 9 is connected to the crank mechanism 11 which is connected to a connecting rod 10 whose upper end is connected to an eccentric position of the rotating disc 9. Therefore, when the rotary disk 9 is driven to rotate, the movable cylinder 8 is driven back and forth up and down. For example, the rotating disk 9 is driven to rotate at, for example, about 1, OOOrpm by an engine output obtained by reducing the rotation of the output shaft of the engine 3 by a reduction mechanism (not shown). Further, at the lower end of the movable cylinder 8, there is provided an opening 14 through which a striking rod 13 formed at the lower portion of the free piston 12 fitted inside can be projected, as will be described later.

The free piston 12 that can freely move up and down in the axial direction of the main body 2 with respect to the movable cylinder 8 is fitted into the movable cylinder 8. A hitting rod 13 is formed at the lower part of the free piston 12 so that the hitting rod 13 protrudes from the lower opening 14 of the movable cylinder 8 when the free piston 12 moves downward, and an intermediate member described later. Hit the head of the hitting tool 18 through 29. Between the outer periphery of the free piston 12 and the inner peripheral surface of the movable cylinder 8, airtightness is secured by an O-ring 19 fitted on the outer periphery of the free piston 12, and the lower opening 14 of the movable cylinder 8 is hit. Airtightness is secured between the rod 13 and an O-ring 20 fitted in the inner periphery of the lower opening 14. Therefore, the inside of the movable cylinder 8 is divided into an upper air pressure chamber 21 and a lower air pressure chamber 22 by the free piston 12. These pneumatic chambers 21 and 22 are alternately compressed by the movement of the free piston 12 as the movable cylinder 8 moves up and down (the movement of the free piston 12 is accompanied by a delay due to inertia). The free piston 12 is accelerated by the elastic expansion of the compressed air. In this embodiment, an appropriate number of through holes 23 are provided in the side wall of the movable cylinder 8, and when the free piston 12 moves downward, the upper air pressure chamber 21 communicates with the outside, so that the upper air pressure chamber 21 is negative. This prevents the downward acceleration of the free piston 12 from being obstructed, and the lower air pressure chamber 22 becomes negative pressure by allowing the lower air pressure chamber 22 to communicate with the outside when the free piston 12 moves upward. This prevents the upward acceleration of the free piston 12 from being obstructed.

Furthermore, the lower ends of the cylindrical outer shell 4 and the fixed cylinder cylinder 5 are well shown in FIG. In this manner, the lower case 25 is connected, and the striking tool support portion 26 is formed so as to be attached to the lower case 25 or attached to the lower case 25. The hitting tool support portion 26 can appropriately support the hitting tool 18 on the market by being configured as described below. As shown in FIG. 2, the hitting tool 18 has an upper shank part 18a, an intermediate flange 18b, and a lower working part 18c. The lower working portion 18c has a pointed shape so as to give a strong impact to the solid object and effectively crush it.

[0024] The lower case 25 includes an upper portion 25a having substantially the same outer diameter as that of the tubular outer shell 4, and a cylindrical lower portion 25b having a smaller diameter than the upper portion 25a and having a constant inner diameter opened at the lower end. The inner diameter of the cylindrical lower portion 25b is set to be slightly larger than the outer diameter of the intermediate flange 18b of the hitting tool 18. A step portion 25 c is formed at a boundary portion between the upper portion 25 a and the cylindrical lower portion 25 b of the lower case 25.

[0025] A cylindrical guide 28 is provided inside the upper portion 25a of the lower case 25 with an annular space 27 interposed. The cylindrical guide 28 is assembled by an outward flange 28a formed at the upper end of the cylindrical guide 28 being sandwiched between connecting portions of the cylindrical outer shell 4 and the lower case 25. Inside the lower case 25 are also an intermediate member 29 that is placed on the upper end of the upper shank 18a of the hitting tool 18, and a donut-shaped rubber damper 30 that is placed in such a manner as to be placed on the step 25c. A bush 31 is provided as a guide portion, which is press-fitted into the cylindrical lower portion 25b of the lower case 25 so as to guide and insert the upper shank portion 18a in the axial direction thereof.

[0026] The intermediate member 29 is placed on the upper end of the upper shank portion 18a and slidably contacts the inner periphery of the cylindrical guide 28, and the outward flange portion formed at the lower end of the cup portion 29a. 29b. The outward flange portion 29b is in sliding contact with the inner wall of the upper portion 25a of the lower case 25. In this way, the intermediate member 29 is guided in the vertical direction. Further, the lower end of the compression coil panel 32 loaded in the annular space 27 is brought into elastic contact with the upper surface of the outward flange portion 29b of the intermediate member 29. As a result, the intermediate member 29 or the striking tool 18 on which the intermediate member 29 is covered is urged downward. The damper 30 is disposed between the outward flange 29b of the intermediate member 29 and the step 25c of the lower case 25. It is. As will be described later, the damper 30 elastically supports the lower surface of the outward flange portion 29b of the intermediate member 29 in the idle driving state, and prevents an impact from being directly transmitted to the lower case 25.

[0027] At the lower end of the cylindrical lower portion 25b of the lower case 25, a stopper 33 for preventing the hitting tool 18 from coming off is provided. In this embodiment, the stopper 33 includes a stopper lever 35 that can rotate around a shaft 34. This stopper lever 35 is provided with a lever portion 35a and a stopper portion 35b.When the lever portion 35a takes a rotating position where it abuts against the side surface of the cylindrical lower portion 25b as shown by a solid line in FIG. When projecting from the inner wall of the cylindrical lower portion 25b so as to interfere with the intermediate flange portion 18b of the hitting tool 18 in the vertical direction, when the lever portion 35a takes the rotation position indicated by the phantom line in FIG. It is formed so as to be retracted into the inner wall of the cylindrical lower part 25b. When the stopper lever 35 takes the rotation position shown by the solid line in FIG. 2, the hitting tool 18 is prevented from coming off, and when the stopper lever 35 takes the turning position shown by the phantom line in FIG. Therefore, the hitting tool 18 can be easily replaced by operating the stopper lever 35.

Next, the operation of the breaker 1 having the above configuration will be described.

[0029] The hitting tool 18 has a cylindrical shape because its upper shank portion 18a is inserted and supported by the bush 31, and an intermediate member 29 that covers the upper end of the upper shank portion 18a is guided to the inner wall of the lower case 25. It is stably supported so as to be movable back and forth along the axial direction of the outer shell 4 and along its own axial direction.

[0030] In the work, the worker holds the hitting tool 18 against the hit target. At this time, the apparatus is subjected to weight and pressing force by the operator, and the compression coil panel 32 is somewhat compressed. That is, the apparatus main body 2 is in a floating state with respect to the striking tool 18 via the compression coil spring 32. When the engine speed is increased by operating the throttle lever (not shown), the movable cylinder 8 is driven back and forth. At this time, the lower air pressure chamber 22 and the upper air pressure chamber 21 are alternately compressed by the inertial force of the free piston 12. More specifically, the lower air pressure chamber 22 is compressed to the maximum when the movable cylinder 8 moves from the lowering process through the bottom dead center to the ascending process, and the elastic expansion of the lower air pressure room 22 automatically The movable cylinder 8 continues to rise while accelerating the piston 12 upward. The movable cylinder 8 eventually passes through the top dead center and begins to descend.The free piston 12 that has been raised by the elastic expansion of the lower air pressure chamber 22 will continue to rise due to the inertial force. Therefore, the upper air pressure chamber 21 is greatly compressed. Thus, as the movable cylinder 8 descends, the free piston 12 is accelerated downward by elastic expansion of the upper air pressure chamber 21 compressed to the maximum. The striking rod 13 of the free piston 12 thus accelerated to the maximum hits the intermediate member 29 placed on the upper end of the striking tool 18 and gives the striking tool 18 an extremely strong impact force downward. In this way, the impact force applied to the striking tool 18 by the free piston 12 accelerated without mechanical restraint in the axial direction of the device is repeatedly applied with such a large impact. Tool 18 can effectively crush objects. Thus, in the operating state, as described above, the apparatus main body 2 is in a floating state with respect to the striking tool 18 and the free piston 12 that is not mechanically restrained in the vertical direction impacts the striking tool 18. As a result, the device body 2 is less susceptible to impact reaction. Therefore, the required strength of the constituent members that can never be damaged when the device body 2 is damaged by the impact is relatively small. As a result, the weight of the entire apparatus can be reduced.

[0031] On the other hand, in the idle driving state, that is, in the state where the hitting tool 18 is not abutted against the object, the hitting bar 13 of the free piston 12 hits the intermediate member 29. Absorbed by 30. Moreover, since the damper 30 receives a relatively large area, that is, the lower surface of the outward flange portion 29b of the intermediate member 29, the impact absorbing effect on the device or the lower case 25b is great. As described above, the breaker 1 of this embodiment also has a complete countermeasure in the idle driving state.

[0032] As described above, in this embodiment, the intermediate member 29 has the cup portion 29a that covers the upper end of the upper shank portion 18a of the batting tool 18, and the outward flange portion 29b at the lower end of the cup portion 29a. It is supposed to provide. Therefore, as described above, the expansion of the vertical dimension of the device is minimized even though the compression coil spring 32 is loaded to float the device main body 2 with respect to the striking tool 18 in the operating state. It is suppressed to. Also, since this intermediate member 29 is used, the material of this intermediate member 29 is If it is possible to withstand the strong impact of the hitting rod 13 of the free piston 12, there is no problem in using a commercially available hitting tool 18.

[0033] Further, as described above, the replacement of the commercially available hitting tool 18 can be performed very easily.

[0034] Of course, the scope of the present invention is not limited to the above-described embodiments, and all modifications within the scope described in each claim are included in the scope of the present invention.

Claims

The scope of the claims

[1] The main body,

A movable cylinder having a lower opening that is reciprocated in the vertical direction inside the main body;

A free piston fitted in the movable cylinder so as to be movable in the vertical direction and having a hitting rod at the lower part protruding from the lower opening of the movable cylinder;

The hitting tool support provided at the lower part of the main body,

A hitting tool that is detachably supported by the hitting tool support, and a breaker comprising:

The hitting tool includes an upper shank part, an intermediate flange, and a lower working part, and the hitting tool support part includes a guide part for holding a part of the upper shank part of the hitting tool in the axial direction; An intermediate member which is placed on the upper end of the upper shank portion of the hitting tool and whose upper surface has a cup portion which is hit by the hitting rod of the free piston and which is guided to be movable in the vertical direction inside the main body, and the hitting tool A breaker, comprising: a stagger that can select a state in which the intermediate flange interferes with the intermediate flange in a vertical direction and a state in which the intermediate flange does not interfere with the intermediate flange.

[2] The intermediate member according to claim 1, wherein the intermediate member has an outward flange portion at a lower end of the cup portion, and an outer periphery of the outward flange portion is vertically guided by an inner wall of the main body. breaker.

[3] The breaker according to claim 2, wherein a lower end of a coil panel for urging the intermediate member downward is brought into contact with an upper surface of the outward flange portion of the intermediate member.

[4] The breaker according to claim 3, wherein an elastic member supported by the main body is disposed below the outward flange portion of the intermediate member.

[5] The breaker according to any one of claims 1 to 4, wherein the stopper is operated by a lever.