TWI792834B - Vibration-absorbing structure of pneumatic impact tool - Google Patents

Abstract

A vibration damping structure of a pneumatic impact tool, comprising an outer shell, an inner pipe, a supporting ring and an air sealing ring. The outer shell is provided with an air intake channel. The outer diameter of the inner pipe is slightly smaller than the inner diameter of the outer shell, which is accommodated in the outer shell. A hammer that can be driven by high-pressure gas is arranged in the inner pipe. There is an air chamber connected with the air intake passage between the inner pipe part and the outer shell. The support ring and the air-tight ring are arranged on the outer circumference of the inner pipe, and the support ring is supported by the inner wall of the outer shell, so that a cylindrical gap is formed between the outer shell and the inner pipe, which is connected with the air chamber, and the air-tight The ring is located away from the rear end of the inner pipe, and is in close contact with the outer shell and the inner pipe.

Description

Vibration-absorbing structure of pneumatic impact tool

The present invention relates to a pneumatic impact tool, in particular to a vibration damping structure of a pneumatic impact tool.

What is shown in Figure 6 is a known pneumatic impact tool, which includes a shell tube 91, whose rear end is closed with an end plug 92, and the shell tube 91 is screwed to a base 93, which can be used for connecting high-pressure gas A hammer body 94 that can be driven by high-pressure gas is provided in the shell tube 91, and a tool head 95 that can be struck by the hammer body 94 to produce a working effect is provided at the front end of the shell tube 91. Because the hammer body 94 will vibrate when it is driven by the high-pressure gas, causing discomfort to the user's hands, an elastic buffer block 96 is arranged behind the end plug 92 to reduce the vibration of the shell tube 91 . However, since the end plug 92 is tightly fitted on the shell tube 91 to be fixed, and the shell tube 91 and the base 93 are tightly locked by threads, the buffer block 96 is pressed by the shell tube 91 on the base 93 for positioning, so that it deforms. Poor cushioning ability affects the effect of vibration reduction.

New patent announcement No. 471377 and M467540 respectively disclose a pneumatic impact tool using a spring to reduce vibration. The common point of the two is that a spring is arranged behind the hammer body, and the new patent No. 471377 is provided with another spring in front of the hammer body. , No. M467540 new patent is provided with curved shrapnel in front of the hammer body, so that the hammer body is driven by high-pressure gas, and can be buffered by the rear spring when moving backward, and can be buffered by the front spring or curved shrapnel when moving forward , to achieve the purpose of reducing vibration. However, the operating frequency of the hammer body is as high as thousands of times per minute, that is, the aforementioned spring or curved shrapnel must withstand thousands of times of compression/extension deformation per minute, and the action speed of returning to its original shape is not fast enough due to the inherent limitations of the material properties. , and cannot return to its original shape before being compressed next time, the effect of vibration reduction will be limited.

In view of this, how to improve the above problems is the primary task to be solved by the present invention.

The main purpose of the present invention is to provide a vibration damping structure of a pneumatic impact tool, which uses high-pressure gas to surround the inner pipe to generate a stable support force for the inner pipe, thereby forming the effect of reducing vibration during work.

In order to achieve the aforementioned purpose, the present invention provides a vibration damping structure of a pneumatic impact tool, which is characterized in that it includes: An outer shell, which is provided with an air inlet and an air inlet channel; An inner pipe fitting accommodated in the outer shell, which includes a small-diameter section and a large-diameter section, the outer diameter of the large-diameter section is slightly smaller than the inner diameter of the outer shell, and a The hammer body driven by high-pressure gas has an air chamber between the rear end of the large-diameter section and the bottom end of the outer shell, wherein the air chamber is connected to the air inlet passage; A supporting ring arranged on the outer periphery of the large-diameter section is supported against the inner wall of the outer cylindrical shell, so that a cylindrical gap is formed between the outer cylindrical shell and the large-diameter section, wherein the cylindrical gap and the The gas chambers are connected; An air-tight ring arranged on the outer periphery of the large-diameter section, which is in close contact with the outer shell and the large-diameter section respectively, wherein the air-tight ring is located more than half the length of the large-diameter section from the rear end of the large-diameter section Location.

Preferably, the inner tube is provided with a first gas flow channel communicating with the air chamber, and the hammer is provided with a second gas flow channel, and the second gas flow channel is selectively connected with the hammer body based on the position change of the hammer body. The first gas channel communicates, thereby changing the direction in which the hammer is driven to move.

Furthermore, the extension directions of the outer shell, the inner pipe, the air inlet channel and the first gas flow channel are respectively parallel to the moving direction of the hammer body.

Preferably, the rear end of the inner pipe is provided with an end plug, and the end plug protrudes a protrusion toward the air chamber, and the protrusion is sheathed with a spring, one end of the spring abuts against the end plug, and the other end abuts against the air chamber. In a groove at the bottom of the outer shell. Furthermore, the end plug is located at the center of the rear end of the large-diameter section, and the position where the air intake channel connects to the air chamber is not directly opposite to the end plug.

Preferably, the front end of the outer shell is locked with a front shell, and a tool head and an impact part are arranged in the front shell, the tool head is connected to the impact part, and the impact part is used to bear the impact of the hammer body. .

Preferably, the small-diameter section of the inner pipe is sheathed with a buffer against the front casing. Furthermore, the two ends of the buffer member are respectively provided with a front tooth portion and a rear tooth portion, and the two are distributed alternately.

Preferably, the inner pipe has a step between the small-diameter section and the large-diameter section, and the air-tight ring is disposed close to the step.

The above objects and advantages of the present invention can be easily understood from the following detailed descriptions and accompanying drawings of selected embodiments.

Please refer to Figures 1 and 2, which show the damping structure of the pneumatic impact tool provided by the present invention; in this embodiment, the pneumatic impact tool is straight. The vibration damping structure of the present invention includes an outer shell 1 , an inner pipe 2 , a support ring 3 and an air seal ring 4 .

The outer cylinder shell 1 is long and straight, and an air inlet passage 11 is arranged inside, and an air inlet 12 is formed at the rear end 10, and the air inlet 12 is used for connecting a high-pressure gas supply source. The air intake passage 11 is provided with a control valve 13 for controlling whether the air flow passes or not, and the control valve 13 is controlled by a trigger 14 arranged on the outer shell 1 in a pressing manner.

The inner pipe 2 includes a small-diameter section 21 and a large-diameter section 22 with a step portion 26 formed therebetween. The inner tube 2 is housed in the outer shell 1, the space between the rear end 20 of the large diameter section 22 and the bottom end 100 of the outer shell 1 is defined as a disc-shaped air chamber 5, and the The air chamber 5 is connected to the air inlet channel 11 at an eccentric position, so that high-pressure gas is controlled by the control valve 13 and injected into the air chamber 5 through the air inlet channel 11 . The outer diameter of the large-diameter section 22 is slightly smaller than the inner diameter of the outer cylindrical shell 1, so that a cylindrical gap 51 is formed between the large-diameter section 22 and the outer cylindrical shell 1, and more importantly, the cylindrical gap 51 It communicates with the air chamber 5 . The outer periphery of the large-diameter section 22 is provided with two support rings 3, which are made of hard materials with wear resistance, such as polytetrafluoroethylene. Referring to Figures 3A and 3B, the above-mentioned support ring 3 is supported against the inner wall of the outer cylindrical shell 1, so that the inner pipe 2 is firmly held in the outer cylindrical shell 1, and at the same time ensures that the large There is a cylindrical gap 51 communicating with the air chamber 5 between the diameter section 22 and the outer cylindrical shell 1 . In this embodiment, two first ring grooves 221 are formed on the outer periphery of the large-diameter section 22 for inserting the support ring 3 therein. Accordingly, when the high-pressure gas is injected into the air chamber 5 , the high-pressure gas is also filled into the cylindrical gap 51 , thereby forming a surrounding of the inner tube 2 .

In addition, the outer periphery of the large-diameter section 22 is provided with at least one air-tight ring 4 that is in close contact with the outer shell 1 and the large-diameter section 22 to block the air flow. The air-tight ring 4 is located behind the large-diameter section 22 The position above the half length of the large diameter section 22 of the end 20. Since the large-diameter section 22 is constantly displaced due to vibration, the air-sealing ring 4 on the large-diameter section 22 is constantly rubbed against the outer shell 1. Therefore, in this embodiment, the air-sealing ring There are two 4, which are respectively in close contact with the outer cylinder shell 1 and the large-diameter section 22, thereby blocking the passage of air flow, so as to prevent the gas in the air chamber 5 and the cylindrical gap 51 from leaking out. Furthermore, as shown in Figures 1 and 2, the air seal ring 4 of this embodiment is located at the position of the large-diameter section 22 close to the step portion 26, thereby ensuring that the cylindrical gap 51 has a sufficient depth for the large-diameter section 22. The diameter section 22 forms an enclosure. In addition, two second ring grooves 222 are provided between the two first ring grooves 221 on the outer periphery of the large-diameter section 22 for inserting the air seal ring 4 therein.

An end plug 23 is screwed at the center of the rear end 20 of the large-diameter section 22 , and a protrusion 231 protrudes from the end plug 23 toward the air chamber 5 . The air chamber 5 is provided with a set of spring 232 outside the protrusion 231, one end of the spring 232 is against the end plug 23, and the other end is against a groove 15 at the bottom of the outer shell 1, so that The spring 232 will not interfere with the intake passage 11 . The inner pipe 2 is provided with a first gas channel 24, which connects the air chamber 5 and the inner space 25 of the inner pipe 2; and the inner space 25 of the inner pipe 2 is provided with a A hammer body 6 movable between the hammer body 6 is provided with a T-shaped second gas flow channel 61 . When the hammer body 6 was in the rear position as shown in Figure 4, the second gas passage 61 was connected to the first gas passage 24, and the high-pressure gas could enter the first gas passage 24. The second gas channel 61 impacts the end plug 23 and pushes the hammer body 6 forward by rebounding. Next, when the hammer body 6 moves to the front position as shown in Fig. 5, the second gas channel 61 is staggered from the first gas channel 24 and does not communicate with each other, and the high-pressure gas will directly push the hammer Body 6 moves backwards until this rear position. Utilizing continuous injection of high-pressure gas, the hammer body 6 will generate back and forth displacements in the inner tube 2 repeatedly.

The front end of the outer cylinder shell 1 is connected with a front cylinder shell 7 , wherein the two are mutually locked by threads 16 , 70 . A cushioning member 8 is sheathed on the small diameter section 21 of the inner pipe member 2 , and its two ends respectively abut against the step portion 26 and the front shell 7 . The buffer member 8 can be rubber or spring. When the hammer body 6 is driven by high-pressure gas to make the inner tube 2 vibrate, the buffer member 8 can be deformed to absorb the vibration. In this embodiment, the front end 81 and the rear end 82 of the above-mentioned buffer member 8 respectively have a front tooth portion 811 and a rear tooth portion 821, and the teeth of the two are in a staggered distribution, so that it can be more properly generated when subjected to vibration. Deformation to dampen vibrations.

A tool head 71 and a striking portion 72 are disposed in the front casing 7 . The structure of the tool head 71 can be selected according to actual usage requirements. The impact portion 72 is against the rear end of the tool head 71 to receive the force of repeated forward impact of the hammer body 6 , and then transmit the force to the tool head 71 to make it move forward.

The extension directions of the outer shell 1, the inner tube 2, the air inlet channel 11, and the first gas flow channel 24 are respectively parallel to the moving direction of the hammer body 6, thereby making the entire pneumatic impact tool form a straight shape. the structural type.

After the high-pressure gas is introduced from the air inlet 12, enters the air chamber 5 through the air inlet channel 11, and then injects into the inner space 25 of the inner tube 2 through the first gas flow channel 24, the hammer body 6 will be compressed by high pressure. The gas is driven to move back and forth repeatedly so that the tool head 71 can impact the workpiece, and at the same time cause the inner pipe 2 to vibrate. According to the above structure, when the high-pressure gas is introduced into the air chamber 5, the high-pressure gas will also fill the cylindrical gap 51 between the outer cylindrical shell 1 and the inner pipe part 2, thereby forming an inner pipe part 2. Full radial holding power. In addition, when the inner pipe 2 vibrates due to the action of the hammer body 6, since the high-pressure gas is a substance without a specific shape, it will not produce the shaking feeling when it is squeezed, as when a hard object collides, so it can suppress vibration The cushioning effect can effectively reduce vibration. Furthermore, because the high-pressure gas fills the air chamber 5 and the cylindrical gap 51 at the same time, it can evenly act on the inner pipe 2 to maximize the vibration damping effect.

However, the disclosure of the above embodiments is only used to illustrate the present invention, not to limit the present invention. For example, the replacement of equivalent components, such as the shape of the outer cylinder shell into the shape of a pistol, etc., should still belong to the scope of the present invention.

To sum up, those skilled in the art can understand that the present invention can clearly achieve the above-mentioned purpose, and it actually complies with the provisions of the Patent Law, so they should file an application according to the law.

1: Outer shell 10: Backend 100: Bottom 11: Intake channel 12: air inlet 13: Control valve 14: trigger 15: Groove 16: Thread 2: Inner pipe fittings 20: Backend 21: small diameter section 22: Large diameter section 221: First Ring Groove 222:Second Ring Groove 23: End plug 231: convex part 232: spring 24: The first gas channel 25: inner space 26: step department 3: support ring 4: Gas sealing ring 5: air chamber 51: Cylindrical gap 6: hammer body 61: Second gas channel 7: Front shell 70: Thread 71: Tool head 72: impact part 8: Buffer 81: front end 811: front teeth 82:Backend 821: rear teeth 91: shell tube 92: end plug 93: base 94: hammer body 95: Tool head 96: buffer block

Figure 1 is a three-dimensional exploded schematic diagram of the present invention; Figure 2 is a schematic cross-sectional view of the present invention; Figure 3A is an enlarged schematic view of part A in Figure 1; Figure 3B is an enlarged schematic view of part B in Figure 1; Figures 4 and 5 are schematic diagrams of the action of the present invention in use; Fig. 6 is a three-dimensional exploded schematic diagram of a conventional structure.

1: Outer shell

2: Inner pipe fittings

221: First Ring Groove

222:Second Ring Groove

3: support ring

4: Gas sealing ring

5: air chamber

51: Cylindrical gap

Claims (8)

A vibration damping structure of a pneumatic impact tool is characterized in that it includes: an outer cylinder shell, which is provided with an air inlet and an air intake passage; an inner pipe part contained in the outer cylinder shell, which includes a small A diameter section and a large diameter section, the outer diameter of the large diameter section is slightly smaller than the inner diameter of the outer shell, a hammer body that can be driven by high-pressure gas is arranged in the inner pipe, and the rear end of the large diameter section is connected to the outer shell. There is an air chamber between the bottom ends of the cylinder shell, wherein the air chamber is connected to the air inlet passage; the inner pipe is provided with a first gas flow passage communicating with the air chamber, and the hammer body is provided with a second air flow passage. The second gas channel selectively communicates with the first gas channel based on the position change of the hammer body, thereby changing the direction in which the hammer body is driven to move; a support ring arranged on the outer periphery of the large diameter section, which Supported against the inner wall of the outer cylindrical shell, a cylindrical gap is formed between the outer cylindrical shell and the large diameter section, wherein the cylindrical gap communicates with the air chamber; one is arranged on the outer periphery of the large diameter section The air sealing ring is in close contact with the outer shell and the large-diameter section respectively, wherein the air-sealing ring is located more than half the length of the large-diameter section from the rear end of the large-diameter section. The vibration-damping structure of the pneumatic impact tool according to claim 1, wherein the extension directions of the outer shell, the inner pipe, the air inlet channel, and the first gas flow channel are respectively parallel to the moving direction of the hammer body . The vibration-damping structure of a pneumatic impact tool according to claim 1, wherein the rear end of the large-diameter section is screw-locked with an end plug, and the end plug protrudes a protrusion toward the air chamber. A spring is sheathed on the convex part, and one end of the spring is against the end plug, and the other end is against a groove at the bottom of the outer shell. The vibration-damping structure of a pneumatic impact tool according to claim 3, wherein the end plug is located at the center of the rear end of the large-diameter section, and the position where the air inlet passage connects to the air chamber is not directly opposite to the end plug. The vibration damping structure of the pneumatic impact tool as described in claim 1, wherein, the front end of the outer shell is locked with a front shell, and a tool head and an impact part are arranged in the front shell, and the tool head is connected to the The impact part is used to bear the impact of the hammer body. The vibration-damping structure of the pneumatic impact tool according to claim 5, wherein a cushioning member abutting against the front shell is sheathed on the small-diameter section of the inner pipe. The vibration-damping structure of the pneumatic impact tool according to claim 6, wherein, the two ends of the buffer member are respectively provided with a front tooth portion and a rear tooth portion, and the two are arranged in a staggered manner. The vibration damping structure of a pneumatic impact tool according to claim 1, wherein the inner pipe has a step between the small diameter section and the large diameter section, and the air sealing ring is provided at a position close to the step .

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