JPH09254054A - Grip part structure for impact tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grip part structure for an impact tool which improves operability further with vibroisolation surely capable. SOLUTION: This impact tool is constituted by providing a group part 3 in one end of a cylinder casing 2, arranging an impact position 1 in the cylinder casing 2, forming a first/second air chamber 21, 22 in both sides of the impact piston 1, alternately supplying a fluid of compressed air or the like to the first/ second air chamber 21, 22, reciprocating the impact piston 1, protruding a tip end of a pick hammer 6 from the cylinder casing 2 and striking a base end part of the pick hammer 6 so as to impact-crush a hard surface of concrete or the like, Here, the grip part 3 is mounted turnably around a support shaft 8, also an elastic unit is interposed between this support shaft 8 and the grip part 3, vibration from the impact position 1 and the pick hammer 6 is constituted to be made absorbable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripping structure for a hand-held hammering tool such as a concrete breaker for crushing, drilling or drilling a hard surface such as concrete or rock.

[0002]

2. Description of the Related Art Hand-held concrete breakers are often used as impact tools for crushing, drilling and drilling hard surfaces such as concrete and rocks in civil engineering construction sites, on-site construction and underground construction. ing.

Such concrete breakers are generally
A striking piston is arranged in a cylinder casing having a grip portion at one end, and compressed air is alternately supplied to the first and second air chambers formed on both sides of the striking piston to reciprocate the striking piston. It is configured to hit the base end of a pick hammer whose tip projects from the cylinder casing.

The gripping structure of the concrete breaker has not been subjected to any anti-vibration treatment as shown in FIG.

That is, in the structure of the grip portion of the concrete breaker X described above, the head body 200 serving as a grip portion is continuously connected to the upper end of the cylinder casing 100 having a long cylindrical body in which the cylinder chamber 110 is formed by a bolt or the like. The head body 200 is integrally provided with left and right handles 210, 210. 220 is a soft handle cover.

In FIG. 4, 300 is the head body 200.
Is an automatic valve that is installed between the air supply unit 230 and the cylinder chamber 110 that are connected to the valve chest.
310, a valve body 320 mounted on the valve chest 310 so as to be movable up and down, a valve cover 330 disposed on the valve body 320, and the like.

A valve ball 400 automatically closes an air supply hole 240 provided on the upstream side of the automatic valve 300 by the force of compressed air.

With the above structure, when the lever 500 provided on the upper end of the head body 200 is operated, the valve ball 400 is pushed through the push rod 410 to open the air supply hole 240, and the compressed air is supplied from a compressed air supply source (not shown). Air is alternately supplied to the first air chamber 120 and the second air chamber (not shown) of the cylinder chamber 110 through the automatic valve 300,
A striking piston (not shown) reciprocally slides in the cylinder chamber 110 to strike and drive the base end of a pick hammer (not shown) whose tip projects from the cylinder casing 100.

[0009]

However, since the conventional concrete breaker X is not subjected to any anti-vibration treatment as described above, vibration caused by the violent reciprocating motion of the striking piston and the pick hammer, especially when the pick hammer is on the concrete surface or the like. Vibration due to impact when crushing the
It will be transmitted to.

Therefore, an intense vibration is transmitted to the operator who is directly gripping the handles 210, 210, and the operator is forced to suffer vibration fatigue. If such an operation takes a long time,
There was a risk of causing nerve damage and causing white wax.

Therefore, various attempts have been made to reduce the vibration, such as incorporating an air cushion or an O-ring type elastic body, but none of them have achieved a satisfactory effect.

It is an object of the present invention to provide a gripping part structure of a striking tool which can solve the above problems.

[0013]

According to the present invention, a striking piston is arranged in a cylinder casing having a grip portion at one end, and compressed air is provided in first and second air chambers formed on both sides of the striking piston. In a striking tool for striking and crushing a hard surface such as concrete by striking the base end portion of a hammer body having a tip protruding from the cylinder casing by reciprocating the striking piston by alternately supplying fluids such as The grip part is attached rotatably around the support shaft, and an elastic body is interposed between the support shaft and the grip part so that vibrations from the striking piston and the hammer body can be absorbed. The present invention relates to a structure of a grip portion of a striking tool.

Further, according to the present invention, the above-mentioned gripping portion is composed of left and right grips provided in an opposed state, and a vibration absorbing body is provided with a cylindrical elastic body in a connecting hole formed at a base end of each grip. The unit was press-fitted, and each handle was attached rotatably around the spindle through the vibration absorbing unit. Furthermore, the vibration absorbing unit was non-rotatably attached to the cylinder casing side and part of the spindle was attached. And an inner metal cylinder that constitutes the inner metal cylinder, and an outer metal cylinder that is concentrically arranged outside the inner metal cylinder and is press-fitted into the connection hole of each handle, and a cylindrical rubber body fixed between both metal cylinders. It also has features.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a striking piston is arranged in a cylinder casing having a grip portion at one end, and compressed air or the like is stored in first and second air chambers formed on both sides of the striking piston. In a striking tool for striking and crushing a hard surface such as concrete by striking the base end portion of a hammer body such as a pick hammer whose tip is projected from the cylinder casing by reciprocating the striking piston by alternately supplying a fluid, The gripping part is attached rotatably around a support shaft, and an elastic body is interposed between the support shaft and the gripping part so that vibrations from the striking piston and the hammer body can be absorbed.

The impact tool can be suitably used for a concrete breaker driven by compressed air, and by significantly reducing vibration, it is possible to significantly reduce the burden on the operator.

That is, the gripping portion is composed of left and right grips provided facing each other, and a vibration absorbing unit having a cylindrical elastic body is press-fitted into a connecting hole formed at the base end of each grip. The respective handles are attached rotatably around the support shaft through the vibration absorbing unit.

Therefore, since it is possible to crush the concrete surface and the like while holding the grips with the right and left hands and holding the hammering tool in a state of being pressed downward, the hammering tool is easy to handle and the workability is good. .

Further, the vibration absorbing unit is arranged non-rotatably on the cylinder casing side and constitutes an inner metal cylinder forming a part of the support shaft, and is concentrically arranged on the outer side of the inner metal cylinder, and each handle is provided. It can be composed of an outer metal cylinder press-fitted into the connecting hole and a cylindrical rubber body fixed between both metal cylinders.

With this construction, the vertical vibration of the cylinder casing is greatly reduced because the handle can be rotated around the support shaft, and the elastic body of the vibration absorbing unit interposed between the support shaft and the handle, That is, the twisting of the cylindrical rubber body absorbs the vibration from the cylinder casing.

As described above, for a person who works by directly gripping the left and right grips, the vibration transmitted to the hand is greatly reduced, so that vibration fatigue is eliminated and it is possible to prevent the occurrence of nerve damage, white wax, and the like. it can.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an entire concrete breaker A as a striking tool having a grip portion structure according to the present invention.
An enlarged view of a main part is shown in FIG. 1. First, the overall configuration of the concrete breaker A in this embodiment will be described.

As shown in FIG. 1, the concrete breaker A is provided with a back head 4 having a grip portion 3 at the upper end of a cylinder casing 2 having a cylinder chamber 20 in which a striking piston 1 is arranged, and a cylinder casing. A cylindrical front head 5 is continuously provided at the lower end of 2, and a pick hammer 6 as a hammer body is slidably attached to the front head 5 with its tip protruding.

Reference numeral 24 is a discharge port provided in the cylinder casing 2, which communicates the cylinder chamber 20 with the atmosphere. Also,
40 is a bolt connecting the cylinder casing 2 and the back head 4, 61 is a hammer holding metal fitting, and 62 is a spring for urging the holding metal fitting 61.

The cylinder chamber 20 has a first air chamber 21 and a second air chamber 22 formed on both sides of the striking piston 1.

The back head 4 has an air supply unit 41.
Is connected to an unillustrated compressed air supply source (compressor or the like), and the compressed air is an automatic valve provided on the downstream side of the air supply unit 41. It is possible to alternately communicate with the first air chamber 21 and the second air chamber 22 through the V and the air flow path 23 formed in the peripheral wall of the cylinder casing 2.

In addition, an air supply hole is provided in the middle of the flow path connecting the opening of the air supply portion 41 with the automatic valve V.
42 is formed (see FIG. 2), and a valve ball 43 is arranged so as to open and close the supply hole 42.

The operating lever 7 is attached to the back head 4 via the push rod 44 so as to push the valve ball 43 to open the air supply hole 42. Reference numeral 45 is a spring for urging the valve ball 43, and 46 is a connecting tube connected to the air supply unit 41.

The automatic valve V is built in between the cylinder casing 2 and the back head 4, and a bellmouth-shaped valve main body 12 is vertically movably mounted in an annular valve chest 11. A valve cover 13 is provided above the main body 12 with a slight gap therebetween. Reference numeral 14 is a disc spring that biases the valve cover 13 downward.

With the above structure, when the operating lever 7 is operated, the valve ball 43 is pushed through the push rod 44 and the air supply hole 42 is opened.

The compressed air from the compressed air supply source is
Valve body 12 and valve cover of automatic valve V
The air is exhausted from the cylinder chamber 20 through the discharge port 24 through the gap with the valve 13, and the valve body 12 is raised due to the difference in the vertical pressure receiving area of the valve body 12.

When the valve body 12 rises, the compressed air becomes
It passes through the gap between the valve body 12 and the valve chest 11 and further through the air flow path 23 to reach the second air chamber 22, which acts on the lower surface of the striking piston 1 to raise it.

When the striking piston 1 rises and passes through the discharge port 24, the compressed air in the second air chamber 22 is discharged to the atmosphere, the second air chamber 22 becomes atmospheric pressure, and the valve body 12
Since the compressed air always acts on the upper surface of the valve body 12, the valve body 12 descends.

When the valve body 12 descends, the compressed air becomes
From the gap between the valve body 12 and the valve cover 13 to the first air chamber
It flows into the inside 21, pressurizes the upper surface of the striking piston 1, and the piston 1 accelerates and descends.

At this time, the striking rod 1a connected to the lower end of the striking piston 1 strongly strikes the upper end of the pick hammer 6.

By repeating this action, compressed air is alternately supplied to the first air chamber 21 and the second air chamber 22, the striking piston 1 slides back and forth in the cylinder chamber 20, and the pick hammer 6
Can be driven to crush the surface of concrete or the like.

In the concrete breaker A having the above-mentioned structure, the gist of the present invention is that the grip portion 3 is rotatably mounted around the support shaft 8 and the support shaft 8 and the grip portion 3 are provided.
This is because an elastic body is provided between and to absorb vibrations from the striking piston 1 and the pick hammer 6.

In this embodiment, the grip portion 3 is composed of the left and right grips 30, 30 provided in an opposed state. As shown in FIGS. 2 and 3, the connection formed at the base end of each grip 30. A vibration absorbing unit U having a cylindrical elastic body is press-fitted into the hole 31, and each handle is inserted through the vibration absorbing unit U.
30 can be rotated around the support shaft 8. 30a and 30a are handles
It is a soft grip cover that covers 30,30.

The vibration absorbing unit U is disposed on the cylinder casing side in a non-rotatable manner, and has an inner metal cylinder 91 which constitutes a part of a support shaft, and is arranged concentrically outside the inner metal cylinder 91. An outer metal cylinder 92 is press-fitted into the connection hole 31 of each handle 30, and a cylindrical rubber body 9 is baked and fixed between the metal cylinders 91 and 92.

Specifically, the two handles 30, 30 are, respectively,
Connecting ears formed on the back head 4 in a U-shape in plan view
The base is rotatably supported between 47 and 47.

That is, a connecting hole provided at the base of each handle 30.
The inner metal cylinder 91 of the vibration absorbing unit U press-fitted in 31 is provided with the engaging portion 91a, and the engaging portion 91a is engaged with the engaging step portions 48, 48 provided on the connecting ears 47, 47 to prevent rotation. And
A spring pin 80 constituting the support shaft 8 is press-fitted through an inner hole of the inner metal cylinder 91 and a pin insertion hole 49 provided in the connecting ears 47, 47.

Therefore, substantially, the support shaft 8 is constituted by the inner metal cylinder 91 of the vibration absorbing unit U and the spring pin 80, and the handle 30 surrounds the outer metal cylinder 92 and the rubber body 9 is attached. It will rotate by the amount of twist.

Such twisting absorbs the vibration transmitted from the cylinder casing 2 to the handle 30, that is, the grip portion 3, and the vibration transmitted to the hand of the operator who directly grips the left and right handles 30, 30 is greatly reduced. The vibration fatigue given to the operator can be remarkably reduced, and the occurrence of nerve damage, white wax, etc. can be prevented.

Moreover, the vibration absorbing unit U has a simple structure and can be manufactured at a low cost, but can sufficiently fulfill the function of absorbing vibration.

In this embodiment, the operation lever 7 is rotatably connected around the vibration absorbing unit U described above.

That is, as shown in FIGS. 2 and 3, a slit portion 32 is provided on the base side of the right handle 30 (left side in the drawing), and the operating lever 7 is provided in the slit portion 32.
The vibration absorbing unit U
It is loosely fitted in the outer metal tube 92 of.

The mounting base 70 has a pressing portion 71 for pressing the push rod 44 toward the valve ball 43. Reference numeral 72 is a lever return spring, and 73 is a lever stopper.

With this structure, in the concrete breaker A, the operating lever 7 can be easily operated while the grips 30, 30 are surely gripped by the left and right hands.

Moreover, the grips 30 and 30 are the vibration absorbing unit U.
Since it is rotatably supported via the
The concrete breaker A can be crushed while holding the concrete breaker A firmly pressed downward through the handles 30 and 30, so that the concrete breaker A can be easily handled and the workability is improved.

Here, the other structure of the concrete breaker A according to this embodiment will be described. In FIGS. 1 and 2, reference numeral 51 denotes a lubricating oil chamber provided in the back head 4, and the upper surface of the lubricating oil chamber 51. Is covered with a lid 52.

The lubricating oil chamber 51 and the location of the automatic valve V are connected by a lubricating oil passage 53, and an oil control section 54 filled with felt is provided in the middle of the lubricating oil passage 53. An appropriate amount of lubricating oil can be supplied to each operating portion of the automatic valve V.

The supply of the lubricating oil to the lubricating oil chamber 51 can be performed by removing the plug 55 provided on the lid 52.

[0054]

EFFECTS OF THE INVENTION A striking piston is arranged in a cylinder casing having a grip portion at one end, and a fluid such as compressed air is alternately supplied to first and second air chambers formed on both sides of the striking piston. In a striking tool for striking and crushing a hard surface such as concrete by striking the base end of a hammer body whose tip projects from the cylinder casing, the gripping portion is rotated around a spindle. In addition to being movably mounted, an elastic body is interposed between the support shaft and the grip to absorb vibrations from the striking piston and hammer body, which greatly reduces the vibration transmitted to the hands of workers. The vibration fatigue given to the operator can be remarkably reduced, and it is possible to prevent the occurrence of nerve damage, white wax disease and the like.

The gripping part is composed of left and right grips provided facing each other, and a vibration absorbing unit having a cylindrical elastic body is press-fitted into a connecting hole formed at the base end of each grip. By attaching each handle rotatably around the support shaft via the vibration absorbing unit, you can grasp the handle securely with your left and right hands and crush the concrete surface while holding the impact tool downward. Since the work can be performed, the impact tool can be easily handled and the workability is improved.

The vibration absorbing unit is non-rotatably attached to the cylinder casing side and constitutes an inner metal cylinder forming a part of the support shaft, and is concentrically arranged outside the inner metal cylinder.
The outer metal cylinder press-fitted into the connecting hole of each handle and the cylindrical rubber body fixed between both metal cylinders make it possible to manufacture with a simple structure at low cost, but with the function of absorbing vibration. It can be fully fulfilled.

[Brief description of drawings]

FIG. 1 is an overall explanatory view of a striking tool including a grip structure according to the present invention.

FIG. 2 is an enlarged view of a main part showing the structure of the grip portion.

FIG. 3 is a partial cross-sectional explanatory view of the same grip portion structure in plan view.

FIG. 4 is an explanatory view showing a grip portion structure of a concrete breaker as a conventional striking tool.

[Explanation of symbols]

 A Concrete breaker U Vibration absorption unit V Automatic valve 1 Strike piston 2 Cylinder casing 3 Grip section 4 Back head 5 Front head 6 Hammer body (pick hammer) 7 Operating lever 8 Spindle 9 Rubber body 30 Handle 91 Inner metal tube 92 Outer metal tube

Claims (3)

[Claims] 1. A first and a second air formed on both sides of a striking piston (1) in a cylinder casing (2) having a gripping portion (3) at one end thereof. Chamber (21), (22)
Fluid such as compressed air is alternately supplied to the striking piston (1)
In a striking tool for striking and crushing a hard surface such as concrete by striking the base end of a hammer body (6) whose tip projects from the cylinder casing (2), the gripping portion (3) Is attached so as to be rotatable around the support shaft (8), and an elastic body is provided between the support shaft (8) and the gripping part (3) so that the impact piston (1) and hammer body (6) The structure of a gripping part of a striking tool, which is configured to be capable of absorbing the vibration of the. 2. The gripping part (3) is composed of left and right handles (30), (30) provided facing each other, and in a connecting hole (31) formed at the base end of each handle (30), The vibration absorption unit (U) equipped with a cylindrical elastic body is press-fitted to the same vibration absorption unit.
2. The gripping part structure for a striking tool according to claim 1, wherein each grip (30) is rotatably mounted around the support shaft (8) via the (U). 3. The vibration absorbing unit (U) includes an inner metal cylinder (91) which is non-rotatably attached to the cylinder casing (2) side and constitutes a part of a support shaft (8), and an inner metal cylinder (91). The outer metal cylinder (92), which is concentrically arranged outside of (91) and is press-fitted into the connecting hole (31) of each handle (30), and the cylindrical shape fixed between both metal cylinders (91), (92). The grip part structure of the impact tool according to claim 2, wherein the grip part structure is composed of the rubber body (9).