Impact tool

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to an impact tool that is driven by an electric motor and performs operations such as impact crushing, and more particularly to an impact tool that has low vibration, low noise, and a long life.

【0002】

[Conventional technology]

Impact tools that perform work such as impact crushing have a large amount of vibration and noise during work, causing various diseases due to vibration transmission to the human body, noise pollution to workers and their surroundings, fatigue destruction of various parts due to vibration, etc. .. As a countermeasure against such a problem, for example, by arranging an elastic member such as rubber between the grasping portion and the main body, vibration transmission to the operator is reduced. Further, as another example of countermeasures, there is an example in which an elastic member is arranged in the reciprocating direction of the meson or the tip tool to buffer the impact in the reciprocating direction.

【0003】

[Problems to be Solved by the Invention]

In the case of the above-mentioned conventional technique, it is possible to reduce the vibration of the gripping portion by, for example, performing vibration insulation of the gripping portion, but in the case of normal work, the operator holds the gripping portion with one hand and the other hand. In many cases, the side handle attached near the cylinder case of the main body is gripped or the main body is directly gripped to perform the work, and the vibration of the main body is directly transmitted to the operator.

【0004】

Further, in the case of the shock buffer in the reciprocating direction of the intermediate and the tip tool described above, the vibration transmitted in the reciprocating direction can be reduced, but the vibration generated by the collision of the work material, the tip tool, the intermediate, the striking element, etc. is the tip. There is a problem that vibration and noise cannot be transmitted to the tool holding member and the cylinder in the radial direction, and then vibration and noise are transmitted to each part via the casing.

【0005】

An object of the present invention is to effectively insulate the radial transmission of vibration generated by a collision of a work material, a tip tool, an intermediate, a striking element, etc. in the vicinity of a vibration source, thereby vibrating the entire product. The purpose is to provide impact tools that reduce noise, reduce fatigue, and prevent fatigue damage of parts.

【0006】

[Means for solving problems]

In order to achieve the above object, the invention of claim 1 reciprocates by a piston driven by an electric motor and reciprocating in a cylinder via a crankshaft and a fluctuation in air pressure in an air chamber provided between the piston and a striking element. An impact tool that reciprocates a driving striker, an intermediate that collides with the striker, and a tip tool attached to the tip tool holding member due to the collision of the intermediate to perform work such as crushing concrete, and holds the tip tool. It is characterized in that at least a part of the tip tool holding portion of the member is composed of a steel material layer and an elastic member layer in the radial direction.

【0007】

The invention of claim 2 is the invention of claim 1, wherein at least a part of the tip tool holding portion of the tip tool holding member is composed of a steel material layer on the outer peripheral portion and the inner peripheral portion in contact with the tip tool. It is characterized in that an elastic member layer is arranged between the two.

【0008】

In the invention of claim 3, in the invention of claim 1, at least a part of the meson is formed of a steel material layer on the outer peripheral portion and the inner peripheral portion where at least a part of the meson comes into contact with the tip tool, and an elastic member layer is arranged between the steel material layers. It is characterized by being done.

【0009】

The invention of claim 4 is a piston that is driven by an electric motor and reciprocates in a cylinder via a crankshaft, a striking element that is reciprocated by fluctuations in air pressure in an air chamber provided between the piston and the striking element, and the striking element. An impact tool that reciprocates the intermediate that collides with the child and the tip tool attached to the tip tool holding member due to the collision of the intermediate to perform work such as crushing concrete, and at least the tip tool holding portion of the tip tool holding member. The outer peripheral portion and the inner peripheral portion in contact with the tip tool are partially composed of a steel material layer, an elastic member layer is arranged between the steel material layers, and at least a part of the intermediate element is the outer peripheral portion and the tip tool. The inner peripheral portion in contact with the steel material layer is composed of a steel material layer, and an elastic member layer is arranged between the steel material layers.

【0010】

BEST MODE FOR CARRYING OUT THE INVENTION

Examples of the impact tool according to the present invention will be described. FIG. 1 is a cross-sectional view of an impact tool showing an embodiment of the present invention, and FIG. 2 is a partial cross-sectional view showing the vicinity of the tip tool holding portion and the tip tool holding portion of the meson. The basic operation of the impact tool and the details of the invention will be described with reference to FIG.

【0011】

The rotation of the electric motor 9 causes the drive shaft 8 fixed to the electric motor 9 to rotate, and the crankshaft 5 to which the gear 6 is attached rotates via a pinion 7 arranged at one end of the drive shaft 8. To do. The rotation of the crankshaft 5 causes the piston 4 to reciprocate in the cylinder 15 via the connecting rod 11 and the piston pin 12 attached to the crankshaft 5. Due to the reciprocating movement of the piston 4, the air pressure of the air chamber 19 composed of the piston 4, the striking element 3, and the cylinder 15 fluctuates, and the striking element 3 reciprocates due to the air pressure fluctuation.

【0012】

The striking element 3 collides with a meson 2 arranged in the cylinder 15 for the purpose of oil sealing or the like, and the meson 2 collides with a tip tool 16, and the tip tool 16 crushes a work material such as concrete. And so on. Reference numeral 1 is a tip tool holding member for holding the tip tool 16, 13 is a cylinder case for storing a cylinder 15 and the like, 14 is a crankcase for storing a gear 6 and a crankshaft 5 and the like, and 10 is a housing for storing an electric motor 9 and the like. is there. Further, reference numeral 17 is a grasping portion, and a vibration isolator member 18 for vibration insulation to the grasping portion 17 is arranged between the crankcase 14 to which the grasping portion 17 is attached and the housing 10. ..

【0013】

The tip tool holding portion of the tip tool holding member 1 is an elastic member between the inner peripheral steel layer 1a that comes into direct contact with the tip tool 16, the outer peripheral steel layer 1c, the inner peripheral steel layer 1a, and the outer peripheral steel layer 1c. Layer 1b is disposed. Further, also in the tip tool holding portion of the meson 2, the meson inner peripheral steel layer 2a in direct contact with the tip tool 16, the meson outer peripheral steel layer 2c in contact with the cylinder 15, the meson inner peripheral steel layer 2a, and the meson outer periphery A meson elastic member layer 2b is arranged between the steel layer 2c.

【0014】

With the above configuration, the vibration generated by the collision between the striking element 3 and the meson 2, the collision between the meson 2 and the tip tool 16, and the collision between the tip tool 16 and a work material such as concrete (not shown) is generated by the tip tool 16, When transmitting from the meson 2 etc. to the tip tool holding member 1, cylinder 15 etc., it is damped by the elastic member layer 1b and the meson elastic member layer 2b, effectively reducing the vibration of the entire product, so it is transmitted to the operator. It is possible to suppress the vibration caused by the vibration, the noise caused by the vibration of various parts, and the damage of the parts.

【0015】

In the configuration of this embodiment, the elastic member layer 1b and the meson elastic member layer 2b of the tip tool holding member 1 and the meson 2 do not need to be arranged at the same time, and each of them has an effect individually. For example, in the case of this embodiment, when a urethane rubber layer having a thickness of 1 mm is arranged only for the tip tool holding member 1, the noise at a distance of 1 m during crushing work is reduced by about 3 dB, and the vibration value of 13 parts of the cylinder case is 1. It became about / 3. Further, when a urethane rubber layer having a thickness of 1 mm is arranged only for the meson 2, the noise is reduced by about 3.5 dB, and the vibration of the cylinder case 13 part is reduced to about 1/2. Furthermore, the most effective case is when a urethane rubber layer with a thickness of 1 mm is arranged on both the tip tool holding member 1 and the meson 2, the noise is reduced by about 4 dB, and the vibration of 13 parts of the cylinder case is reduced to about 1/5. It was.

【0016】

As the material of the elastic member layer 1b and the meson elastic member layer 2b, the effect is large when an elastic member such as urethane rubber or rubber is used, but the material having lower rigidity than the steel material such as resin is effective. The thickness and length of the elastic member layer 1b and the meson elastic member layer 2b are also effective as they are thicker and longer, but they may be determined according to the dimensions of the product.

【0017】

The method of attaching the elastic member layer 1b to the tip tool holding member 1 may be determined in consideration of assembling property and the like because the attachment method does not affect noise and vibration. For example, in the configuration shown in FIG. 1, since the entire tip tool holding portion has a three-layer structure, it is necessary to perform a process such as baking between the steel layer and the elastic member as a measure to prevent each part from falling off. Select a method that prevents it from falling off, such as inserting a retaining pin. The method of attaching the elastic member layer 2b to the meson 2 is the same. For example, in FIG. 1, a ring of an elastic material may be inserted, but if the meson is manufactured by baking, there is no concern that the elastic member layer 1b will fall off.

【0018】

In this embodiment, in the tip tool holding member 1, the inner peripheral steel layer 1a and the outer peripheral steel layer 1c are completely separated by the elastic member layer 1b, but in the meson 2, the meson inner peripheral steel layer 1a and the meson Since the outer peripheral steel layer 1c is configured as the same member, some vibration transmission from the meson inner peripheral steel layer 2a to the meson outer peripheral steel layer 2c is unavoidable. That is, the above-mentioned configuration of the tip tool holding member 1 has a greater effect of vibration insulation and vibration damping than the configuration of the meson 2. However, since the main object of the present invention is vibration insulation to the casing of vibration, the form of the meson 2 configured to insulate the vibration transmitted in the radial direction from the tip tool 16 is also sufficiently effective.

【0019】

FIG. 3 is a partial cross-sectional view showing the vicinity of the tip tool 16 showing another embodiment of the impact tool according to the present invention. The tip tool holding member 30 has a three-layer structure of an inner peripheral steel layer 30a, an elastic member layer 30b, and an outer peripheral steel layer 30c, as in the embodiment of FIG. At one end of the outer peripheral steel layer in the axial direction, a curved portion 30d is provided so as to prevent the elastic member layer 30b and the inner steel layer 30a from coming off. Further, at the end opposite to the curved portion 30d, a retaining member 31 is press-fitted into the inner peripheral portion of the outer peripheral steel material layer 30c to prevent the elastic member layer 30b and the inner peripheral steel material layer 30a from falling off. ..

【0020】

With the above configuration, it is not necessary to bond the elastic member layer 30b, the outer peripheral steel layer 30c, and the inner peripheral steel layer 30a, and the elastic member layer 30b only needs to insert a ring-shaped member.

【0021】

The curved portion 30d of the outer peripheral steel layer 30c and the inner diameter portion of the retaining member 31 each have the function of preventing the elastic member layer 30b and the inner peripheral steel layer 30a from coming into direct contact with the tip tool 16. It is composed of various dimensions. That is, since only the inner peripheral steel layer 30a is in direct contact with the tip tool 16, it has the same vibration insulation effect as the tip tool holding member 1 shown in FIG.

【0022】

Further, as shown in FIG. 4, the structure may be such that the inner peripheral steel layer 40a and the outer peripheral steel layer 40c are made of the same member, and the rear retaining member 41 in which the elastic member layer 40b is arranged is press-fitted.

【0023】

Further, as shown in FIG. 5, when the tip tool holding member 50 has a two-layer structure of an elastic member layer 50b and an outer peripheral steel material layer 50c, the effect of reducing vibration and noise is large. However, in the case of the above configuration, since the elastic member layer 50b slides directly with the tip tool 16, it is necessary to pay sufficient attention to the material and the lubrication method of the elastic member layer 50b.

【0024】

Needless to say, all of the above-described embodiments of FIGS. 3, 4, and 5 can be applied to the meson 2.

【0025】

[Effect of the invention]

According to the present invention, the radial transmission of vibration generated by the impact of an impact tool such as a hammer, intermediate element, tip tool, work material, etc., which is driven by an electric motor and performs operations such as impact crushing, is transmitted in the vicinity of the vibration source. By effectively insulating the product, the transmission of vibration to the entire product can be reduced and suppressed, and low vibration, low noise, and long life can be achieved.

[Simple explanation of drawings]

[Figure 1]

It is sectional drawing which shows the Example of the impact tool which concerns on this invention.

[Figure 2]

It is a partial cross-sectional view which showed the vicinity of the tip tool holding part of FIG. 1 and the tip tool holding part of a meson.

[Fig. 3]

It is a partial cross-sectional view around the tip tool part which shows the other embodiment of the impact tool which concerns on this invention.

[Fig. 4]

It is a partial cross-sectional view around the tip tool part which shows still another Example of the impact tool which concerns on this invention.

[Fig. 5]

It is a partial cross-sectional view around the tip tool part which shows still another Example of the impact tool which concerns on this invention.

[Explanation of symbols]

1 ... Tip tool holding member, 1a ... Inner circumference steel layer, 1b ... Elastic member layer, 1c ... Outer circumference steel layer, 2 ... Meson, 2a ... Meson inner circumference Steel layer, 2b ... meson elastic member layer, 2c ... meson outer circumference steel layer, 3 ... hammer, 4 ... piston, 5 ... crank shaft, 6 ... gear, 7. .. Pinion, 8 ... Drive shaft, 9 ... Electric, 10 ... Housing, 11 ... Connecting rod, 12 ... Piston pin, 13 ... Cylinder case, 14 ... Crank case , 15 ... Cylinder, 16 ... Tip tool, 17 ... Grasping part, 18 ... Anti-vibration member, 19 ... Air chamber.