TW201325837A - Air hammer tool, and method of adjusting impact force of the air hammer tool - Google Patents

Abstract

To provide an air hammer tool which largely reduces transmission of vibration to a worker, has a simple and light-weight structure, can be manufactured at a low cost and can be easily maintained. An air hammer tool(1A) has a single coil spring(9) (elastic body) externally fitted on the outer periphery of a cylinder portion(11) of sliding body(8), the coil spring(9) as a compression spring is interposed between a spring stop member(16) which is fixed to the front end portion of a main body portion(3b) and a front end face(10a) of the sliding body(8), when a trigger(4a) is operated, the sliding body(8) obtains a state where it is pushed forward by compressed air to elastically contract the coil spring(9), and the sliding body(8) obtains a rearward urged state.

Description

Air hammer tool and striking force adjustment method of the air hammer tool

The invention relates, for example, to a drill (chisel) rock machine, a concrete hole puncher (crusher), a crusher, a nailing machine, a rivet gun (machine), a pile driver, a grader, a hammer drill, a ram ( Boiler tools, crowbars (cookers), road rollers, asphalt or concrete leveling machines, so-called air drills (chiseling), etc. These are hammer tools.

Conventionally, there have been various proposals for the above-described air hammer tools (refer to Japanese Patent Literatures 1 to 4). In addition, the configuration in which the shock generated by the reciprocation of the piston loaded in the hammer tool is not transmitted to the operator's vibration isolating device has been disclosed (see Patent Document 5). For example, in the structure disclosed in Patent Document 5, a buffer chamber filled with a buffer liquid and a buffer cylinder for inserting a buffer sliding body are provided at a rear end portion of the hammer body, and a buffer chamber and a buffer are disposed. A buffer mechanism formed by a communication hole of a buffer air cylinder that communicates inside the air cylinder.

[Previous Technical Literature]

[Patent Document 1] Japanese Patent No. 4340881

[Patent Document 2] Japanese Patent No. 3825802

[Patent Document 3] Japanese Patent No. 2746712

[Patent Document 4] Japanese Patent Laid-Open No. Hei 8-197458

[Patent Document 5] Japanese Patent Laid-Open Publication No. Hei 9-11156

However, the configurations of the above-described Patent Documents 1 to 4 are configured such that the tip end of the drill or the like which obtains the kinetic energy by the impact of the hammer strongly vibrates the tool body, and therefore the tool body also strongly vibrates due to the rebound caused by the vibration. Therefore, in order to prevent the hammer tool from jumping, or the tip end is displaced from the position of the target to be crushed or the like, or to effectively transmit the force generated by the vibration of the tip tool to the target, the operator must keep the work. When the main body of the tool is pressed against strong vibrations, it is transmitted to the operator due to strong vibration, and the long-term use of the operator is highly likely to cause a major problem such as ash. Further, the noise at the time of the operation of the front end member or the collision between the tip end and the hammer causes difficulty in hearing for the operator or the person around the work site.

In the configuration of the above-described Patent Document 5, the above-mentioned problem may be solved. However, in order to fill the tool body with a cushioning liquid capable of sufficiently obtaining a cushioning effect, the buffer chamber must be enlarged, and the weight of the air hammer as a whole is increased. As a result of the increase in weight, there is a problem that the operation is extremely difficult for the operator. Further, since it is necessary to prevent the buffer liquid filled in the air hammer body from leaking out, the internal structure is required to be highly precise and complicated, and there is a problem that the manufacturing cost is high. Furthermore, the number of components of the air hammer tool is also increased, so the disassembly and cleaning is extremely troublesome, so that it cannot be easily produced. Maintenance problems. Therefore, for the reasons described above, the structure disclosed in Patent Document 5 is extremely lacking in practicality, and is not currently manufactured.

Here, the present invention provides an air hammer tool that can greatly reduce the vibration and noise transmitted to an operator, has a simple structure and is lightweight, can be manufactured at low cost, and can be easily maintained, and a striking force adjustment method of the air hammer tool. for purpose.

The present invention is an air hammer tool characterized in that it is provided with a cover body and a front end piece projecting forward from the cover body, and the impact object is pressed into the cover body via the front end piece. The air hammer tool of the striking force of the gas, the cover body has an inner hollow portion formed along the front-rear direction, and a gas pressure that presses the gas forward to the inner hollow portion is formed on the peripheral wall of the cover body a sliding portion that is slidable back and forth, and an elastic body interposed between an outer circumferential surface of the sliding body and an inner circumferential surface of the casing, and the sliding body has a sliding body And a cylindrical air cylinder portion that is provided to protrude forward from the cover body at a front end portion of the slider body, and a gas that is pressed into the cover body is introduced into the air cylinder portion on a peripheral wall of the air cylinder portion. a gas introduction portion is provided with a hammer that can slide back and forth in the gas cylinder portion, and a rear end portion of the front end member that hits the hammer is fixed to a front end opening portion of the gas cylinder portion, and the gas is pressed in through the gas pressing portion. In the aforementioned cover The sliding body advances while elastically deforming the elastic body in the cover body by the pressure of the gas, and the gas is introduced into the gas cylinder portion through the gas introduction portion, and the hammer reciprocates back and forth in the gas cylinder portion. The rear end portion of the front end tool is repeatedly struck to obtain the aforementioned striking force.

As described above, the air hammer tool of the present invention is characterized in that the cover body and the sliding body in which the hammer striking the front end member are inserted are separated, and the elastic body is sandwiched between the cover body and the sliding body. between. In the related structure, the hammer generated in the sliding body and the impact generated when the front end has an impact, or the inertia of the hammer that reciprocates, is absorbed by the elastic body, so that large vibration is not easily transmitted to the operation of holding the cover. By.

Further, in the air hammer tool of the present invention, the first feature point is added, and the second feature point is that the air cylinder portion and the front end member are fixed so that the front end member cannot move relative to the air cylinder portion. In the related configuration, when the hitting force is applied to the work, the front end tool is brought into contact with the hitting target and the hammer tool is actuated. In this way, when the hammer in the air cylinder portion hits the front end, the front end functions as a so-called drill, and the striker is applied to the target by the strike force generated by the inertia of the hammer. Therefore, the conventional structure that gives the striking target striking force by the vibration of the front end itself does not strongly vibrate compared to the air hammer tool, and the noise generated by the vibration of the front end itself does not occur. Therefore, in combination with the advantages of the first feature point described above, it is possible to provide a hammer tool that greatly reduces the vibration and noise transmitted to the operator and fully considers the operator and the like.

Further, in the above-described air hammer tool of the present invention, the third characteristic point is that the front end has a forward position at the front end by the gas being pushed into the sliding body, and the gas pressure is interrupted during the interruption. At the time of entry, the restoring force of the elastic body returns to the original position, and the front end has a retracted position. That is, when the work is interrupted, usually, the operator has to perform the gas injection of the stop gas and the front end tool should be removed from the impact object itself. The action of hitting the object. However, in the present invention, even if the operation of the hammer tool itself is not intentionally moved away from the target, the front end itself can be retracted away from the target. Therefore, for example, when many operations (strikes) are sequentially performed using the air hammer tool of the present invention, it is not necessary to perform the operation of moving the air hammer tool itself away from the striking object every time the work is interrupted, and the front end can be exchanged each time the object is hit. Hit the object.

In the above configuration, the structure is such that the elastic body is a coil spring, and the coil spring is interposed between the front end surface of the sliding body and the inner peripheral surface of the cover body in a state of being aligned in the front-rear direction, and the gas is interposed therebetween. When the gas press-fitting portion is press-fitted into the cover body to advance the slider, the coil spring is biased rearward to load the slider.

When the sliding body advances, the coil spring that is biased rearward to load the sliding body has both the function of absorbing the hammer generated in the sliding body and the impact generated when the front end member collides, or the inertia of the hammer reciprocating, and interrupting the operation. The function of returning the sliding body to the original position when the gas is pressed in is stopped. Further, the air hammer tool of the related structure is an elastic body made of a solid material that does not use a buffer liquid, and it is not necessary to add a large-sized mechanism other than the coil spring, so that it is an extremely simple internal structure. Therefore, the increase in the overall weight can be suppressed, and the entire tool becomes compact and compact. Thereby, workability is good and maintenance convenience is excellent.

Here, in the configuration in which the coil spring interposed between the front end surface of the sliding body and the inner circumferential surface of the cover body is attached, the absorption function of the coil spring or the like is greatly increased. Reduce the vibration transmitted to the operator, but also take into account the rebound force of the coil spring due to use. When the sliding body is loaded rearward, the pressing force of the target of the tip end is reduced, and the overall striking force is weakened, or when the supply of the injecting gas for extruding the sliding body to the front is unstable. The sliding body jumps in the cover body and cannot obtain a stable striking force. Here, further improvements are required, and the following structures are proposed.

That is, the structure is such that the coil spring as the elastic body is also aligned in the front-rear direction, and the state of the contraction is interposed between the rear end surface of the sliding body and the inner peripheral surface of the cover body, the coil spring, in the gas The sliding body is loaded forward in a state in which the sliding body advances in a state in which the gas pressing portion is press-fitted into the cover.

In the above configuration, when the slider advances, the coil spring that is biased toward the front is loaded, and the slider is appropriately biased to appropriately bias the tip end to the target, and the slider can be prevented from jumping. Thereby, a stable striking force can be obtained.

Furthermore, the present invention provides a method for adjusting a striking force of an air hammer tool, characterized in that a coil spring interposed between a front end surface of the sliding body and an inner circumferential surface of the cover body is a first coil spring, The coil spring interposed between the rear end surface of the slider and the inner peripheral surface of the cover is a second coil spring, and the striking force is adjusted by changing the biasing force of the slider of the second coil spring.

For example, if the biasing force of the aforementioned sliding body of the second coil spring is increased, the striking force is increased, and for these, the striking force is reduced if the loading force is weakened. With the related structure, it is possible to easily adjust the striking force of the hammer tool while preventing large vibrations from being transmitted to the operator.

Moreover, the following structures may also be used. In other words, the air control body that supplies the gas from the outside is disposed in the rear of the cover, and is introduced from the outside by the operation of the switch of the air control switch unit provided on the air control unit. The gas press-in portion provided in the cover body is configured to have a tubular grip mounted on the outer circumference of the cover body and/or the outer periphery of the air control body in the front-rear direction via the elastic member body.

The aforementioned holding body, the opposite cover, or the air control body is attached via the elastic member. Therefore, when the operator holds the gripping body, the elastic member absorbs the front and rear vibrations generated in the air cylinder portion, and the vibration transmitted to the operator can be greatly suppressed. For example, by the operator holding the grip body mounted on the cover body with one hand and holding the grip portion mounted on the air control body with the other hand, the work can be greatly reduced due to vibration. burden.

The air hammer tool of the present invention has the effects of greatly reducing the vibration and noise transmitted to the operator, and is easy to manufacture at a low cost because of its simple structure and light weight, and can be easily maintained. Further, the striking force adjusting method of the air hammer tool of the present invention has an effect of being able to easily finely adjust the striking force.

1A to 1C‧‧‧Air Hammer Tools

2‧‧‧ Cover

2a‧‧‧Internal Department

3a‧‧‧Hands

3b‧‧‧ Body Department

4a‧‧‧ trigger

4b‧‧‧ gas supply port

5‧‧‧ Valve

6a‧‧‧Gas press-in department

6b‧‧‧Exhaust port

6c‧‧‧Air tube extension hole

7‧‧‧Compressed air inflow room

8‧‧‧Sliding body

8a‧‧‧ front opening

9, 91, 92‧‧‧Helical springs (elastomers)

10‧‧‧Sliding body

10a‧‧‧ front face

11‧‧‧Air tube department

11a‧‧‧Outer tube

12‧‧‧O type washer

13‧‧‧ gas discharge transfer

14a‧‧‧Gas introduction department

14c‧‧‧Gas supply and discharge switching valve

15‧‧‧ card specific

16‧‧‧Spring fixed part

16a‧‧‧ (spring fixed part) rear end face

16b‧‧‧ end face

17‧‧‧ bearing parts

20‧‧‧ front end

20a‧‧‧Chisel Department

20b‧‧‧Clamping Department

20c‧‧‧The rear end of the front end

30‧‧‧ Hammer

50‧‧‧Air control body

52‧‧‧Air control switch

74‧‧‧ Front side control body

75, 85‧‧‧O type washer

78a, 78b, 94‧‧‧Helical springs (elastic parts)

84‧‧‧ Back side control

Fig. 1 is a longitudinal sectional view showing an air hammer tool.

Fig. 2 is a longitudinal sectional view showing another state of the hammer tool.

Fig. 3 is a cross-sectional view taken along line A-A of Fig. 1;

Fig. 4 is a longitudinal sectional view showing an enlarged portion of the inside of the gas cylinder portion.

Fig. 5 is a graph showing the comparison between the hammer tool and the conventional product relating to the vibration absorbing performance, (a) showing the average value, and (b) showing the change in the performance of the product of the present invention over time, (c) ) indicates the performance change of the past product over time.

Fig. 6 is a conceptual diagram showing a measurement state.

Fig. 7 is a longitudinal sectional view showing an air hammer tool of another form.

Fig. 8 is a longitudinal sectional view showing an air hammer tool of another form.

An embodiment of the air hammer tool of the present invention will be described with reference to the drawings.

For convenience of explanation, the front end direction of the air hammer tool is the front side and the base end direction is the rear side, but it is not excluded to use the air hammer tool up or down. Further, the air hammer tool of the present invention is not limited to the embodiment described below, and may be appropriately designed and changed without departing from the critical scope of the invention.

As shown in Fig. 1, the air hammer tool 1A is a tool that uses compressed air (gas), and includes a cover 2 that presses the compressed air from the outside, and a front end 20 that protrudes forward from the cover 2 .

The cover body 2 is made of a metal material, and has a handle 3a that is held by an operator during work, and a substantially cylindrical body portion 3b that is connected to the upper portion of the handle portion 3a in the front-rear direction. .

A trigger portion 4a is disposed at a front portion of the handle portion 3a. By operating the trigger portion 4a, the supply of compressed air to the hammer tool 1a can be controlled. Further, at the lower end of the handle portion 3a, an air supply port 4b for introducing compressed air from the outside is provided.

And introducing compressed air from the outside to the cover 2, and by the foregoing The trigger portion 4a is free to control the inflowing compressed air introduction mechanism of the compressed air, and a well-known mechanism is used.

The main body portion 3b has an inner hollow portion 2a formed along the front-rear direction. Further, a gas pressing portion 6a for pressing compressed air into the inner hollow portion 2a is provided on the peripheral wall of the rear end of the main body portion 3b. Further, a valve 5 is housed in the gas pressing portion 6a. The compressed air introduced from the handle portion 3a flows into the inner hollow portion 2a of the main body portion 3b via the valve 5. Further, the peripheral wall of the front end of the main body portion 3b is provided with an exhaust portion 6b, and the compressed air introduced into the main body portion 3b can be discharged to the outside.

Further, a sliding body 8 slidable in the front-rear direction is loaded in the inner hollow portion 2a of the main body portion 3b. The slider 8 is made of a metal material, as shown in Fig. 1, having a cylindrical body portion 10 having a larger diameter and extending forward from the center of the front end face 10a of the slider body portion 10. A cylindrical air cylinder portion 11 is formed. Further, the air cylinder portion 11 projects from the cover body 2 through the air cylinder portion projecting hole 6c opened at the front end of the main body portion 3b. The bearing member 17 is slidably supported by the bearing member 17 in the inner edge of the gas cylinder portion extending hole 6c.

Further, a plurality of O-rings 12 are fitted to the outer peripheral surface of the slider main body portion 10. The O-ring 12 is in close contact with the inner circumferential surface of the main body portion 3b. Further, in the inner hollow portion 2a of the main body portion 3b, a rear end surface of the sliding body 8 and an inner peripheral surface of the main body portion 3b facing the rear end surface are formed with a highly airtight compressed air inflow. Room 7.

Further, in the slider main body portion 10, as shown in Figs. 3 and 4, a plurality of gas flow paths are bored. Moreover, these multiple strips of gas flow Among the roads, the gas flow path that connects the compressed air inflow chamber 7 and the exhaust portion 6b of the main body portion 3b constitutes the exhaust intermediate portion 13, and is connected to the gas flowing into the chamber 7 and the gas cylinder portion 11 by the compressed air. The flow path constitutes the gas introduction portion 14a.

Further, as shown in Fig. 4, the air cylinder portion 11 of the slider 8 has an outer tubular portion 11a. Further, a gas supply/discharge switching valve 14c is provided at the proximal end portion of the outer tubular portion 11a. In addition, the front opening portion 8a of the outer tubular portion 11a is formed with a mounting portion 18 formed by a thickness of the inner peripheral wall of the front opening portion 8a. The mounting portion 18 is fixed to the opposite portion of the air cylinder portion 11 The aforementioned front end has 20.

As shown in Fig. 4, the front end tool 20 is made of a metal material, has a front end body 22, and has a pile-like chisel portion 20a attached to the front end of the front end body 22, and is formed at the front end. The disc-shaped holding portion 20b at the intermediate portion of the main body 22 and the rear end portion 20c projecting rearward from the center of the nip portion 20b. The rear end portion 20c of the distal end member 20 is inserted into the attachment portion 18 from the front opening portion 8a of the distal end outer tubular portion 11a and protrudes into the air cylinder portion 11, and the surface of the clamping portion 20b abuts The front end surface of the outer tubular portion 11a. Further, at the abutting portion, the cap-shaped card body 15 having the center of the insertion insertion hole 15a at the distal end of the insertion insertion end piece 20 is covered. In a state in which the card body 15 is covered, the nip portion 20b is sandwiched by the inner surface of the card body 15 and the front end surface of the outer tube portion 11a, and is interposed by an O-ring attached to the outer circumference of the mounting portion 18. 15b, the card specific portion 15 is screwed to the front end portion of the air cylinder portion 11. Thereby, the tip end tool 20 does not fall off from the air cylinder portion 11, and can be firmly fixed. Further, the card specific portion 15 is detachable from the air cylinder portion, Thus the front end 20 can be replaced.

Next, the structure of the above-described front end tool 20 will be described in detail.

As shown in Fig. 4, a shaft portion 20e is connected to the base end portion of the chisel portion 20a, and an O-ring 20f is attached to the shaft portion 20e. Further, the shaft portion 20e is fitted and fixed to the front end of the front end body 22. Further, the chisel portion 20a can be appropriately replaced by pulling out the shaft portion 20e with respect to the front end body 22.

Further, as shown in FIG. 4, the nip portion 20b of the distal end main body 22 is formed in a tubular shape further forward. Further, a cushioning material 21 made of a fiber material such as a felt (needle-punched nonwoven fabric) composed of polyester fibers is filled in the front end main body 22, and noise reduction is achieved by the fiber material. Further, in the peripheral wall of the distal end main body 22, a plurality of heat dissipation holes 20d for preventing the thermal energy of the cushioning material 21 from increasing and increasing the temperature are formed in the portion where the cushioning material 21 is filled.

Next, the above-described gas cylinder portion 11 will be described in detail.

A hammer 30 made of a slidable metal material is loaded into the outer tubular portion 11a of the gas cylinder portion 11. The appropriate size or weight of the hammer 30 can be appropriately set.

Further, as shown in Fig. 1 and the like, a single coil spring 9 (elastic body) is externally fitted to the outer circumference of the air cylinder portion 11. As will be described in more detail, the cover body 2 has an annular spring fixing portion 16 provided at a front end portion of the main body portion 3b, and the coil spring 9 is attached to the annular spring in a state of being aligned in the front-rear direction. The rear end surface 16a of the portion 16 and the front end surface 10a of the slider body portion 10 function as a compression spring.

In the case of using the above-described air hammer tool 1A, the front end of the front end tool 20 is placed on a striking object (not shown) such as a rock or a concrete block, and the trigger 4a is actuated. In this way, the compressed air is prevented from flowing back to the air supply port 4b through the gas press-fitting portion 6a of the main body portion 3b by the valve 5, thereby being continuously pressed into the compressed air inflow chamber 7. Further, the compressed air flows into the pressure in the chamber 7, and the sliding body 8 is extruded forward. When the sliding body 8 is extruded forward, as shown in Fig. 2, the volume of the compressed air inflow chamber is expanded, and the coil spring 9 is contracted between the spring fixing portion 16 and the slider body portion 10. The state in which the slider 8 is loaded rearward is obtained.

Then, the compressed air that has been pressed into the main body portion 3b is discharged from the exhaust portion 6b to the outside of the cover 2 via the exhaust intermediate portion 13 formed in the slider body portion 10. At the same time, the compressed air that has been pressed into the main body portion 3b is introduced into the gas cylinder portion 11 through the gas introduction portion 14a of the slider body portion 10, and the flow direction is appropriately controlled by the gas supply/discharge switching valve 14c. The hammer 30 is reciprocated in the front-rear direction. Further, the reciprocating hammer 30 repeatedly hits the rear end portion 20c of the front end tool 20. Thereby, the striking force is continuously applied to the striking target via the distal end tool 20. Further, the mechanism for reciprocating the hammer 30 in the air cylinder portion 11 can be a well-known mechanism. For example, a known mechanism disclosed in Japanese Laid-Open Patent Publication No. Hei 9-11156 is applicable to the hammer tool 1A.

In the above configuration, the cover 2 held by the operator by hand and the slider 8 in which the hammer 30 striking the front end 20 are inserted are separate bodies, and the cover 2 and the slider are sandwiched by the coil spring 9. Between 8, so by the foregoing The coil spring 9 can absorb the impact that occurs when the hammer 30 and the front end 20 collide, or the inertia of the hammer 30 that reciprocates. Therefore, it is possible to effectively suppress the vibration from being transmitted to the operator who uses the hammer tool 1A.

Further, the distal end tool 20 and the slider 8 are integrally formed, and the striking force generated when the hammer 30 collides is transmitted to the target, whereby a large vibration is not transmitted to the handle portion 3a of the cover 2. Therefore, the hammer tool 1A has a very slight vibration compared with the hammer tool of the conventional structure having a vibration at the front end, and as a result, it is possible to suppress ash or hearing which occurs in the operator due to the use of the hammer tool of the conventional structure. Major problems such as difficult obstacles occur.

Further, the hammer tool 1A has a simple internal structure and a small number of parts, and can be made compact and lightweight. Therefore, the manufacturing cost can be reduced. Moreover, the decomposition is also easy and has the advantage of being easy to maintain.

Further, in the hammer tool 1A, the front end tool 20 is in a forward protruding position (see FIG. 1), and the pressure is released from the pressure of the compressed air when the operation trigger 4a is interrupted, and the coil spring is used. The loading force of 9 returns the slider 8 to the original position, and the tip end 20 becomes the retracted position (refer to Fig. 2). That is, in the air hammer tool 1A, if the compressed air is stopped by the interruption of the operation, the front end 20 itself is to be avoided at the rear and leaves the striking object. Therefore, for example, when a lot of work (battering target) is sequentially performed, it is not necessary to perform the operation of moving the hammer tool 1A itself away from the hitting target every time the work is interrupted. Thereby, for example, the strike target can be sequentially exchanged in cooperation with the front end tool 20 retreat timing.

For reference, the noise measured by the test piece corresponding to the above structure, The noise measured by the conventional general-purpose product which does not have the above-mentioned coil spring 9 is about 95 dB (a noise meter used: Model SL-310 Multi Meter Sales Co., Ltd.).

Further, referring to Fig. 5, there is shown a comparison between the hammer tool and the conventional product (without the coil spring 9) according to the present invention regarding the vibration absorbing performance. As for the measurement of the vibration, as shown in Fig. 6, the vibration of the three axes (front and rear, up and down, left and right) in the rear end portion of the tool body was measured using a commercially available three-axis vibrometer. The compressed air pressure used was 0.25 MPa. The measurement time was 10 seconds (T). The shape of the front end 20 is a brush shape. A vibrating meter (model: UV0) manufactured by Rion Corporation was used as the vibrating meter. A measuring instrument (Model: DL750) manufactured by Yokogawa Electric Corporation was used as the measuring instrument. A piezoelectric speed sensor is manufactured by Rion Co., Ltd. (model: PV-97C). A vibration corrector (model: VE-10) manufactured by Rion Corporation was used as the vibration corrector.

As shown in Fig. 5a, it was confirmed from the results of the measurement that the product of the present invention is excellent in vibration absorption performance of the three axes as compared with the conventional product. Especially in front and rear vibration, an attenuation of about 92% can be obtained. Further, as shown in Figs. 5b and c, the measured value measured by the above-described three-axis vibrometer is obtained as a stable value in the measurement time. Thus, the vibration absorption performance of the air hammer tool related to the present invention can be determined, which is remarkably improved according to objective measurement.

[Example 2]

In the following, the air hammer tool 1B according to the second embodiment will be described. The same reference numerals are given to the same points as those in the first embodiment, and the same reference numerals are used in the drawings.

As shown in Fig. 7, the hammer tool 1B includes a first coil spring 91 and a second coil spring 92. The first coil spring 91 is in the front and rear direction The aligned state is interposed between the front end surface 10a of the slider body portion 10 in the slider 8 and the front inner peripheral end surface 25a of the cover body 2. The second coil spring 92 is attached to the rear end surface 10b of the slider main body portion 10 of the slider body 8 in a state of being aligned in the front-rear direction, and an end surface 16b formed on the inner peripheral surface of the main body portion 3b located behind the rear end surface 10b. between. Further, in these mounted states, the second coil spring 92 is in a contracted state, and the slider 8 is loaded forward.

Further, a support body 40 composed of a well-known bearing member is disposed in the cover body 2, and the support body 40 contacts the side surface portion of the slider body 8 and moves back and forth to freely support the slider body 8, thereby preventing the The sliding of the slider 8 is performed.

When the hammer tool 1B of the above configuration is used, the trigger 4a is continuously pushed into the compressed air inflow chamber 7 to press the compressed air. In this way, the compressed air flows into the pressure in the chamber 7, and the slider 8 is pushed forward while being supported by the support 40. In a state in which the slider 8 is pushed forward, the first coil spring 91 is in a contracted state and the slider 8 is loaded rearward, and the second coil spring 92 is loaded forward in the state in which the slider 8 is loaded. Further, in this state, the reciprocating motion of the hammer 30 in the air cylinder portion 11 repeatedly hits the front end tool 20, so that the striking force is continuously applied to the striking object via the front end tool 20.

In these configurations, the vibration absorbing effect and the noise suppressing effect can be obtained by the first coil spring 91 on the front side. Further, by the second coil spring 92 on the rear side, it is possible to obtain an effect of appropriately compressing the sliding body 8 by the pressure of the compressed air to stabilize the striking force forward.

For reference, it is determined by the test piece corresponding to the above-mentioned Example 2. The striking force is increased by about 20 to 30% as compared with the striking force of the trial work of the first embodiment which does not have the second coil spring 92. For the measurement of the striking force, the exercise energy transmitted from the tip end tool 20 is measured by a measuring device that is numerically based on acceleration.

Here, by appropriately setting the spring constant of the second coil spring 92, the most suitable vibration absorbing effect and noise suppressing effect can be maintained, and the striking force to which the target is applied can be adjusted.

For example, when it is desired to enhance the striking force, the spring constant of the second coil spring 92 is changed to increase the biasing force of the slider 8 toward the front. In this manner, the sliding body 8 is appropriately biased forward, and the distal end device 20 is appropriately biased against the target, and the sliding of the sliding body 8 in the inner hollow portion 2a is prevented, so that the striking force is enhanced. On the other hand, when it is desired to weaken the striking force, the spring constant of the second coil spring 92 is changed to weaken the biasing force of the slider 8 toward the front. As a result, the striking force is weakened based on the opposite principle described above.

[Example 3]

Further, another form of the air hammer tool 1C having the above structure is proposed. The points common to the first and second embodiments are abbreviated or omitted, and the same reference numerals are used in the drawings.

As shown in Fig. 8, an air control body 50 is disposed behind the cover 2. The air control body 50 is provided with an air control body 51. A gas flow path 55 in the front-rear direction is formed in the inside of the air control body 51 in a through shape.

Further, an air control switch unit 52 is provided outside the air control body 51. The air control switch unit 52 includes an operation unit 52A and an operation unit 52B. The operation portion 52A is composed of an elongated plate member, and its base end portion is supported It is supported on the side wall of the air control body 51. Further, the actuating portion 52B is formed of a bar projecting outward from the inside of the air control body 51, and its distal end abuts against the rear surface of the distal end operating portion 52A. Further, when the operation portion 52A is operated, the actuation portion 52B moves up and down along the axial direction thereof. Further, an opening and closing valve 54 built in the air control body 51 is connected to the starting portion 52B. When the operation unit 52A is operated, the opening and closing valve 54 is actuated in conjunction with the actuation unit 52B, and the gas flow path 55 is appropriately opened and closed. The mechanism of the opening and closing valve 54 can be applied to a well-known technique. For example, the well-known mechanism disclosed in Japanese Utility Model Registration No. 3153805 can be applied to the hammer tool 1C.

Further, between the air control body 50 and the cover 2, the gas press-fitting portion 6a of the cover 2 and the gas flow path 55 in the air control body 50 are formed in an airtight manner.

Further, on the outer circumference of the cover 2 described above, a cylindrical front side holding body 74 is externally fitted via elastic members O-shaped washers 75, 75. In this state, the O-rings 75, 75 are sandwiched between the cover 2 and the front side holding body 74 to be in close contact with each other.

Further, coil springs 78a, 78b as elastic members are interposed in front of and behind the front side holding body 74. Specifically, a flange-shaped spring fixing portion 76a is provided around the front end portion of the cover body 2, and the cover portion 2 is disposed between the spring fixing portion 76a and the front end surface of the front side grip portion 74. Coil spring 78a. On the other hand, a flange-shaped spring fixing portion 76b is provided on the rear end portion of the cover body 2, and the cover body 2 is covered between the spring fixing portion 76b and the rear end surface of the front side grip portion 74. The coil spring 78b is disposed. The O-ring 75 has a vibration absorbing function that allows the left and right vibrations generated in the cover 2 to be hardly transmitted to the front grip portion 74. Further, the coil springs 78a and 78b have a vibration absorbing function that makes it difficult for the front and rear vibrations generated in the cover body 2 to be transmitted to the front side grip portion 74.

Further, a rear side grip body 84 is attached to the rear portion of the air control body 50 described above. The rear side holding body 84 is composed of a bottomed cylindrical member. Further, the rear side holding body 84 is externally attached to the air control body 50 via O-rings 85, 85 as elastic members. Further, coil springs 94, 94 as elastic members are interposed between the rear end surface of the air control body 50 and the bottom portion of the rear side holding body 84, that is, the rear end portion. The O-ring 85 has a vibration absorbing function that allows the left and right vibrations transmitted to the air control body 50 to be easily transmitted to the rear side holding body 84. Further, the coil spring 94 has a vibration absorbing function that makes it difficult for the front and rear vibrations transmitted to the air control body 50 to be transmitted to the rear side holding body 84.

Further, a bulging portion 58 having a large diameter is provided at a rear end portion of the air control body 51. Further, an annular braking portion 86 is fixed to the front end of the rear side holding body 84 by a bolt 88. In the related configuration, it is assumed that even if the rear side holding body 84 is to be detached rearward from the air control body 51, the braking portion 86 and the bulging portion 58 can be buckled to prevent falling off.

Further, a compressed air introduction portion 96 is disposed on the rear end surface of the rear side holding body 84. The compressed air introduced from the outside through the compressed air introduction portion 96 passes through the air flow path 89 in the rear side holding body 84, and then is guided to the gas flow path 55 in the air control body 50.

In the above configuration, when the air control switch unit 52 of the air control unit 50 is operated by a switch, the compressed air is first supplied from the outside to the gas flow path 55 of the air control unit 50 via the compressed air introduction unit 96, and then The gas press-fitting portion 6a of the cover 2 is guided into the cover 2. Thereby, the hammer 30 is rocked back and forth.

Here, since the front side grip body 74 is provided around the cover body 2, and the rear side grip body 84 is provided in the vicinity of the air control switch unit 52, the operator can hold the front side grip portion 74 with one hand, and the other The hand grips the rear side grip body 84 to perform work. With the related configuration, even for the hand that operates the air control switch unit 52, the hand that supports the entire hammer tool 1C is hard to be transmitted due to vibration, so that the vibration absorbing performance is extremely good.

In the other aspect of the invention, the cover 2 or the distal end member 20 may be made of other materials. For example, the handle portion 3a of the first embodiment may be made of an elastic material such as rubber which is easy to hold. Further, the material of the hammer 30 may be appropriately selected from known materials, and may also be composed of a core material and an outer casing covering the core material. Further, the hammer 30 may be subjected to an appropriate surface treatment. Further, a plurality of blocks may be coupled to each other to constitute the hammer 30, and the strike force or weight composition of the hammer 30 may be adjusted in accordance with the number of the blocks. Further, an elastic body made of a fibrous material may be filled in a necessary portion. As the fiber material, a felt (needle-punched nonwoven fabric) made of a polyester fiber or the like can be used. Further, oil may be impregnated into the aforementioned fibrous material to achieve an improvement in durability of the fibrous material. Furthermore, the front end tool 20 is, for example, a drill (chisel) rock machine or a concrete hole puncher (crusher), and the crusher can be a drill bit, a nailing machine or a rivet gun (machine) or a pile driver. For nails or rivets or piles, is a grader or impact drill Or a ram (a bauxware) or a crowbar (cooker) or a roller or a flat machine can be used to flatten the metal plate on the ground, and if it is an air drill (chisel), it can be a needle bundle or the like. Further, the gas pressed into the hammer tools 1A to 1C is not limited to compressed air, and may be a gas such as an inert gas.

1A‧‧‧Air hammer tool

2‧‧‧ Cover

2a‧‧‧Internal Department

3a‧‧‧Hands

3b‧‧‧ Body Department

4a‧‧‧ trigger

4b‧‧‧ gas supply port

5‧‧‧ Valve

6a‧‧‧Gas press-in department

6b‧‧‧Exhaust port

6c‧‧‧Air tube extension hole

7‧‧‧Compressed air inflow room

8‧‧‧Sliding body

9‧‧‧Helical spring (elastomer)

10‧‧‧Sliding body

10a‧‧‧ front face

11‧‧‧Air tube department

12‧‧‧O type washer

13‧‧‧ gas discharge transfer

14a‧‧‧Gas introduction department

15‧‧‧ card specific

16‧‧‧Spring fixed part

16a‧‧‧ (spring fixed part) rear end face

17‧‧‧ bearing parts

20‧‧‧ front end

20a‧‧‧Chisel Department

Claims (5)

An air hammer tool comprising a cover body and a front end member projecting forward from the cover body, and the striker is provided with a gas that is pressed into the cover body by the front end tool In the air hammer tool, the cover body has an inner hollow portion formed along the front-rear direction, and a gas press-in portion that presses the gas forward to the inner hollow portion is formed on the peripheral wall of the cover body, and the inner hollow portion is formed in the inner hollow portion a sliding body that is slidable back and forth, and an elastic body interposed between an outer circumferential surface of the sliding body and an inner circumferential surface of the sliding body, the sliding body having a sliding body and a body disposed on the sliding body a cylindrical air tube portion that protrudes forward from the cover body at the front end portion, and a gas introduction portion that introduces a gas that is pressed into the cover body into the air cylinder portion is formed in a peripheral wall of the air cylinder portion, and the air cylinder is formed in the air cylinder portion. a hammer that can slide back and forth is loaded in the inside, and a rear end portion of the front end member that can strike the hammer is fixed to a front end opening portion of the air cylinder portion, and when a gas is pressed into the cover body through the gas pressing portion, By the gas The sliding body advances while elastically deforming the elastic body in the cover body, and the gas introduced into the air cylinder portion through the gas introduction portion, the hammer reciprocates back and forth in the gas cylinder portion to repeatedly hit the front end member The rear end portion thus obtains the aforementioned striking force. The air hammer tool according to claim 1, wherein the elastic body is a coil spring. The coil spring is interposed between the front end surface of the sliding body and the inner peripheral surface of the cover body in a state of being aligned in the front-rear direction, and the gas is pressed into the cover body through the gas press-fitting portion, and the sliding body advances. The coil spring is biased to the rear to load the sliding body. The air hammer tool according to claim 2, wherein the coil spring as the elastic body is also aligned in the front-rear direction, and is in a state of being contracted, and is attached to the rear end surface of the sliding body and the inside of the cover body. Between the circumferential surfaces, the coil spring presses the gas into the cover body through the gas press-fitting portion, and the slide body is loaded forward in a state in which the slider body advances. The air hammer tool according to any one of claims 1 to 3, wherein the air control body that supplies the gas from the outside is configured to be disposed at the rear of the cover body and is disposed by operation The switch of the air control switch unit on the air control unit is introduced into the gas press-in portion provided in the cover body, and the gas is supplied from the outside to the outer periphery of the cover body and/or the outer periphery of the air control body. A tubular grip body is externally fitted through the elastic member in the front-rear direction. A method for adjusting a striking force of an air hammer tool, which is a striking force adjusting method for an air hammer tool according to claim 3, which is interposed between a front end surface of the sliding body and an inner circumferential surface of the cover body The coil spring is the first coil spring, The coil spring interposed between the rear end surface of the slider and the inner peripheral surface of the cover is a second coil spring, and the striking force is adjusted by changing the biasing force of the slider of the second coil spring.