CN210139371U

CN210139371U - Front and back cover assembly of pneumatic tool and pneumatic tool

Info

Publication number: CN210139371U
Application number: CN201920757039.6U
Authority: CN
Inventors: 丁志明; 赖泊壬
Original assignee: Hyphone Machine Industry Co Ltd
Current assignee: Hyphone Machine Industry Co Ltd
Priority date: 2019-05-24
Filing date: 2019-05-24
Publication date: 2020-03-13
Anticipated expiration: 2029-05-24

Abstract

The utility model relates to a front and back cover component of a pneumatic tool, which comprises a front cover and a back cover, wherein the front cover and the back cover are arranged on an axis, the front cover comprises at least one first air inlet and outlet hole, and the back cover comprises at least one second air inlet and outlet hole; viewed from the axial direction, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are staggered and arranged at intervals around the axial line, and the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole can be respectively communicated with an air supply source; the utility model discloses a pneumatic tool, it includes a tool main part, a cylinder main part, a rotor and foretell front and back lid subassembly.

Description

Front and back cover assembly of pneumatic tool and pneumatic tool

Technical Field

The utility model relates to a pneumatic tool's front and back lid subassembly and pneumatic tool.

Background

Pneumatic tool is one of the common devices of general task , and is useful for tightening or loosening fastening components such as nuts and bolts, and is popular with many authors. The main reasons for this are that the high-pressure gas used as the power source is easily available, does not pollute the environment, and has high stability and safety.

The pneumatic tool includes one rotating mechanism and one casing, and the casing includes one front casing and one back casing, and the back casing holds the rotating mechanism and has one air inlet channel in the back end. Such as the rotating mechanism disclosed in taiwan patent nos. TW287457 and TWI403395, etc.

However, the efficiency of discharging high-pressure gas is not good, and the high-pressure gas is easily accumulated in the cylinder to affect the rotation of the rotor, which results in poor smoothness during the rotation.

Therefore, there is a need for a novel and improved front and rear cover assembly for a pneumatic tool and a pneumatic tool to solve the above problems.

SUMMERY OF THE UTILITY MODEL

A primary object of the present invention is to provide a front and rear cover assembly of a pneumatic tool and a pneumatic tool, wherein an air inlet and an air outlet are provided in at least one first air inlet and outlet of a front cover and at least one second air inlet and outlet of a rear cover, so as to improve the smooth degree of rotation.

To achieve the above object, the present invention provides a front and rear cover assembly of a pneumatic tool, including: the front cover and the rear cover are arranged on an axis, the front cover comprises at least one first air inlet and outlet hole, and the rear cover comprises at least one second air inlet and outlet hole; viewed from the direction of the axis, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are staggered and arranged at intervals around the axis, and the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are respectively communicated with an air supply source.

In order to achieve the above object, the present invention provides a front and rear cover assembly for a pneumatic tool, for locating a cylinder body, the cylinder body encloses a gas chamber for accommodating a rotor, the cylinder body is provided with at least one forward rotation gas inlet channel at one of the two opposite ends, the other end includes at least one reverse rotation gas inlet channel, the at least one forward rotation gas inlet channel and the at least one reverse rotation gas inlet channel communicate with the gas chamber respectively, the front and rear cover assembly further comprises: the front cover is arranged at one end part of the cylinder main body and comprises at least one first air inlet and outlet hole, the at least one first air inlet and outlet hole corresponds to and is communicated with one of the at least one forward air inlet channel and the at least one reverse air inlet channel, and the at least one first air inlet and outlet hole is communicated with an air supply source; the rear cover is arranged at the opposite end part of the cylinder main body, which is provided with the front cover, and comprises at least one second air inlet and outlet hole, the at least one second air inlet and outlet hole corresponds to and is communicated with the other one of the at least one forward air inlet channel and the at least one reverse air inlet channel, the at least one second air inlet and outlet hole can be communicated with the air supply source, and the front cover and the rear cover are arranged on an axis; the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are disposed around the axis at intervals.

Preferably, the number of the at least one first air inlet/outlet hole is two, and the number of the at least one second air inlet/outlet hole is two.

Preferably, the two first air inlet/outlet holes are arranged diagonally, and the two second air inlet/outlet holes are arranged diagonally.

Preferably, the two first air inlet/outlet holes and the two second air inlet/outlet holes are arranged alternately around the axis when viewed from the axis.

Preferably, at least the front cover or the rear cover has an outer peripheral surface extending around the axial line, the outer peripheral surface has a flow guide groove communicated with the air supply source, the flow guide groove is open in a radial direction, and the flow guide groove is communicated with each of the first air inlet/outlet holes or each of the second air inlet/outlet holes.

Preferably, at least one airtight ring is disposed on at least the front cover or the rear cover, each airtight ring and the guide channel are arranged on the axial line, and each airtight ring radially protrudes from the outer peripheral surface.

Preferably, the rear cover is provided with an end surface on the axial lead, and the end surface is provided with a flow guide groove; the flow guide groove of the rear cover is communicated with the second air inlet and outlet holes and the air supply source, the second air inlet and outlet holes penetrate and open towards two opposite sides of the thickness direction of the rear cover, and the positions of the second air inlet and outlet holes correspond to the positions of the flow guide groove.

Preferably, the two first air inlet and outlet holes are arranged diagonally, and the two second air inlet and outlet holes are arranged diagonally; the two first air inlet/outlet holes and the two second air inlet/outlet holes are arranged alternately around the axis when viewed from the axis; the front cover and the rear cover are respectively provided with the peripheral surface, each first air inlet and outlet hole is provided with a first opening which is opened towards the axial lead and a second opening which is opened towards the radial direction and is arranged in the flow guide groove, and the structure of each second air inlet and outlet hole is the same as that of each first air inlet and outlet hole; the number of the at least one airtight ring part is two, and the flow guide groove is arranged between the two airtight ring parts; each airtight ring part comprises a ring groove and an airtight ring arranged in the ring groove, and the airtight ring part radially protrudes out of the ring groove.

To achieve the above object, the present invention provides a pneumatic tool, which includes: a tool main body, which includes a shell and an air supply part, the shell has an inner peripheral surface, the inner peripheral surface encloses a containing space, the shell defines an axial direction, the shell is provided with a first air inlet channel, a second air inlet channel and an exhaust channel communicated with the air chamber and the outside, the inner peripheral surface is provided with a first annular groove and a second annular groove which are arranged at intervals in the axial direction, the first air inlet channel is communicated with the first annular groove, the second air inlet channel is communicated with the second annular groove, the air supply part and the shell are arranged on the axial direction, the air supply part is provided with two air supply channels, the two air supply channels are respectively communicated with one of the first air inlet channel and the second air inlet channel, and the two air supply channels are respectively communicated with an air supply source; the cylinder body is accommodated in the shell and encloses a gas chamber, at least one forward air inlet channel is arranged at one end part of the two opposite end parts of the cylinder body, at least one reverse air inlet channel is arranged at the other end part of the cylinder body, and the at least one forward air inlet channel and the at least one reverse air inlet channel are respectively communicated with the gas chamber; a rotor eccentrically accommodated in the air chamber; the front cover assembly and the rear cover assembly are arranged on an axis, the front cover assembly comprises at least one first air inlet and outlet hole, the rear cover assembly comprises at least one second air inlet and outlet hole, and the at least one first air inlet and outlet hole is communicated with the at least one second air inlet and outlet hole; looking toward the axial line, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are staggered and arranged at intervals around the axial line, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are respectively communicated with an air supply source, the at least one first air inlet/outlet hole is communicated with the first annular groove, and the at least one second air inlet/outlet hole is communicated with the second annular groove.

The utility model has the advantages that can supply high-pressure gas respectively through this at least first discrepancy gas pocket and this at least second discrepancy gas pocket and admit air and exhaust, make high-pressure gas flow in this air chamber and rotate in order to promote the rotor to can discharge smoothly, so high-pressure gas can smoothly flow in and discharge the air chamber and can not pile up in the air chamber, with the smooth and easy degree of rotation that promotes pneumatic tool and output torque continuously.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description will be given below of the drawings required to be used in the description of the embodiments or the prior art, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a perspective view of a first preferred embodiment of the present invention.

Fig. 2 is an exploded view of a first preferred embodiment of the present invention.

Fig. 3 is another exploded view of a first preferred embodiment of the present invention.

Fig. 4 is a sectional view taken along line a-a of fig. 1.

Fig. 5 is a cross-sectional view taken along line C-C of fig. 4.

Fig. 6 is a cross-sectional view taken along line D-D of fig. 4.

Fig. 7 is an axial perspective view of a first preferred embodiment of the invention.

Fig. 8 is a sectional view taken along line B-B of fig. 1.

Fig. 9 is a sectional view taken along line E-E of fig. 8.

Fig. 10 is a perspective view of a housing according to a first preferred embodiment of the present invention.

Fig. 11 is a perspective view of a front cover according to a first preferred embodiment of the present invention.

Fig. 12 is an axial partial perspective view of a second preferred embodiment of the invention.

Fig. 13 is a perspective view of a third preferred embodiment of the present invention.

Fig. 14 is a sectional view of a third preferred embodiment of the present invention in a use state.

Wherein, 1: front and rear cover assemblies; 10,10': a front cover; 11: a first air inlet and outlet hole; 12,22: an outer peripheral surface; 13: a first opening; 14: a second opening; 15,15',24,24': a flow guide groove; 16,25: an end face; 20,20': a rear cover; 21: a second air inlet and outlet hole; 2: a pneumatic tool; 3: a cylinder body; 30: an air chamber; 31: a positive rotation air inlet channel; 32: reversing the air inlet flow channel; 4: a rotor; 40: a gas-tight ring portion; 41: a ring groove; 42: an airtight ring; 5: a tool body; 6: a housing; 61: an inner peripheral surface; 62: an accommodating space; 63: a first intake runner; 64: a second intake runner; 65: a first ring groove; 66: a second ring groove; 67: an exhaust flow passage; 7: an air supply part; 71,72: an air supply flow channel; l1: a shaft axis; l2: and (4) axial direction.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the drawings in the embodiments of the present invention are combined below to clearly and completely describe the technical solutions in the embodiments of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The following description of the present invention will be made by way of example only, and not by way of limitation, to describe the features and intended functions of the present invention, as illustrated in .

Referring to fig. 1 to 11, a first preferred embodiment of the present invention is shown, in which a front cover assembly 1 and a rear cover assembly 2 of a pneumatic tool of the present invention are provided to a cylinder body 3, the cylinder body 3 is cylindrical, the cylinder body 3 encloses an air chamber 30 for accommodating a rotor 4, at least one forward intake channel 31 is provided at one end of the opposite ends of the cylinder body 3, the other end of the cylinder body includes at least one reverse intake channel 32, the at least one forward intake channel 31 and the at least one reverse intake channel 32 are respectively communicated with the air chamber 30, and the front cover assembly 1 further includes a front cover 10 and a rear cover 20.

The front cover 10 is disposed at an end of the cylinder body 3 and includes at least one first air inlet/outlet hole 11, the at least one first air inlet/outlet hole 11 corresponds to and communicates with one of the at least one forward rotation air inlet channel 31 and the at least one reverse rotation air inlet channel 32, and the at least one first air inlet/outlet hole 11 is used for communicating with an air supply source; the rear cover 20 is disposed at an opposite end of the cylinder body 3 where the front cover 10 is disposed, and includes at least one second air inlet/outlet hole 21, the at least one second air inlet/outlet hole 21 is open towards two different sides of the rear cover 20, the at least one second air inlet/outlet hole 21 corresponds to and communicates with the other of the at least one forward rotation air inlet channel 31 and the at least one reverse rotation air inlet channel 32, the at least one second air inlet/outlet hole 21 is configured to communicate with the air supply source, and the front cover 10 and the rear cover 20 are disposed on an axial line L1; specifically, the at least one forward intake runner 31 and the at least one reverse intake runner 32 of the cylinder block 3 are provided at opposite ends of the cylinder block 3 along the axial line L1; the at least one first air inlet/outlet hole 11 and the at least one second air inlet/outlet hole 21 are disposed around the axial line L1 in a staggered and spaced arrangement from each other when viewed from the axial line L1; thus, the at least one first air inlet/outlet hole 11 and the at least one second air inlet/outlet hole 21 can respectively allow high-pressure gas to enter and exhaust, so that the high-pressure gas flows into the air chamber 30 to push the rotor 4 to rotate and can be smoothly exhausted, and therefore the high-pressure gas can smoothly flow into and exhaust from the air chamber 30 without accumulating in the air chamber 30, thereby improving the smooth rotation and the continuous output torque of the pneumatic tool 2; but also provides a structure with high strength; furthermore, the at least one first air inlet/outlet hole 11 and the at least one second air inlet/outlet hole 21 are disposed with high flexibility.

One of the at least one first air inlet/outlet hole 11 and the at least one second air inlet/outlet hole 21 is a forward air inlet hole, and the other is a reverse air inlet hole. Specifically, high-pressure gas can be selectively input from the at least one first air inlet/outlet hole 11 or the at least one second air inlet/outlet hole 21, so that the high-pressure gas can pass through the at least one forward rotation inlet flow channel 31 or the at least one reverse rotation inlet flow channel 32 to switch forward and reverse torque output, and when one of the at least one first air inlet/outlet hole 11 and the at least one second air inlet/outlet hole 21 is an air inlet/outlet hole, the other one is an air outlet hole.

The number of the at least one first air inlet/outlet hole 11 is two, and the number of the at least one second air inlet/outlet hole 21 is two. Preferably, second first inlet/outlet aperture 11 is diagonally disposed, and second inlet/outlet aperture 21 is diagonally disposed; the number of the at least one forward rotation inlet channel 31 and the number of the at least one reverse rotation inlet channel 32 are matched with the number of the first inlet/outlet air holes 11 and the second inlet/outlet air holes 21. Furthermore, the two first air inlet/outlet holes 11 and the two second air inlet/outlet holes 21 are alternately arranged around the axis L1 as viewed from the axis L1 to increase the output torque. In other embodiments, as shown in fig. 12, the number of the at least one first air hole 11 and the at least one second air hole 21 may be one.

At least the front cover 10 or the rear cover 20 has an outer

peripheral surface

12,22 extending around the axial line L1, the outer peripheral surface has a

flow guide groove

15,24 communicating with the air supply source, the flow guide groove is open in the radial direction, and the flow guide groove communicates with each of the first air inlet/outlet holes 11 or each of the second air inlet/outlet holes 21. In this embodiment, the front cover 10 and the rear cover 20 are respectively provided with the outer

peripheral surfaces

12 and 22, each of the first air inlet/outlet holes 11 is provided with a first opening 13 opening toward the axial line L1 and a second opening 14 opening in the radial direction and provided in the guide groove 15, and each of the second air inlet/outlet holes 21 has the same structure as each of the first air inlet/outlet holes 11; in detail, the flow guiding groove 15 of the front cover 10 is communicated with the two first air inlet and outlet holes 11, and the flow guiding groove 24 of the rear cover 20 is communicated with the two second air inlet and outlet holes 21; thus, the high-pressure gas can be radially input and output to and from the gas chamber 30, and the high-pressure gas can be intensively flowed.

Preferably, at least the front cover 10 or the rear cover 20 is provided with at least one airtight ring portion 40, each airtight ring portion 40 and the

flow guide groove

15,24 are arranged on the axial line L1, and each airtight ring portion 40 radially protrudes from the outer

peripheral surface

12, 22. Preferably, the number of the at least one airtight ring portion 40 is two; taking the rear cover 20 as an example, the guiding groove 24 is disposed between the two airtight rings 40, so that high-pressure gas cannot flow out from the slit between the front cover 10 and the rear cover 20 and the housing 6 of a pneumatic tool 2, and has a better sealing effect to maintain the pressure of the gas. Further, the arrangement of the flow guide channel 13 of the front cover 10 and the air-tight ring portions 40 is the same as that of the rear cover 20; each airtight ring part 40 comprises a ring groove 41 and an airtight ring 42 arranged in the ring groove 41, and the airtight ring part 40 radially protrudes out of the ring groove 41 to improve the positioning effect; it is further illustrated that the number of the at least one gas-tight ring portion 40 can be varied according to the requirements.

Referring to fig. 13 and 14, a third preferred embodiment of the present invention is shown, which is different from the first preferred embodiment in that the rear cover 20 'has an end surface on the axial line L1, and the end surface has a flow guiding groove 24'. In the present embodiment, the front cover 10 'and the rear cover 20' are respectively provided with the

end surfaces

16, 25. Taking the rear cover 20 'as an example, the flow guide groove 24' of the rear cover 20 'is communicated with the second air inlet/outlet holes 21 and the air supply source, the second air inlet/outlet holes 21 are opened through toward two opposite sides of the rear cover 20' in the thickness direction, and the positions of the second air inlet/outlet holes 21 correspond to the positions of the flow guide groove 24; the arrangement of the guide grooves 15 'and the first inlet/outlet holes 11 of the front cover 10' is the same as that of the second outlet holes 21 and the guide grooves 24 'of the rear cover 20', so that high-pressure gas can be axially supplied into and discharged from the gas chamber 30.

The utility model provides a pneumatic tool 2, it includes as above pneumatic tool 2's front and back lid subassembly 1, this pneumatic tool 2 still includes a tool main part 5, this cylinder main part 3 and this rotor 4.

The rotor 4 is eccentrically accommodated in the gas chamber 30. The tool body 5 includes a housing 6 and an air supply portion 7, the housing 6 has an inner peripheral surface 61, the inner peripheral surface 61 encloses a receiving space 62, the housing 6 defines an axial direction L2, the housing 6 is provided with a first air inlet channel 63, a second air inlet channel 64 and an air outlet channel 67 connecting the air chamber 30 and the outside, the inner peripheral surface 61 is provided with a first annular groove 65 and a second annular groove 66 arranged on the axial direction L2 at intervals, the first air inlet channel 63 is communicated with the first annular groove 65, the second air inlet channel 64 is communicated with the second annular groove 66, the air supply portion 7 and the housing 6 are arranged on the axial direction L2, the air supply portion 7 is provided with two

air supply channels

71,72, the two

air supply channels

71,72 are respectively communicated with one of the first air inlet channel 63 and the second air inlet channel 64, in detail, the air supply channel 71 is communicated with the first air inlet channel 63, the second air inlet channel 72 is communicated with the second air inlet channel 64, the two

air supply channels

71,72 are respectively communicated with an air supply source, and the air supply source can be selectively switched to be led into one of the two

air supply channels

71, 72; the cylinder body 3 is accommodated in the housing 6; the at least one first air inlet/outlet hole 11 is communicated with the first annular groove 65, and the at least one second air inlet/outlet hole 21 is communicated with the second annular groove 66, so that the structure is simple, the volume is small, the forward and reverse torque output is switched, and the smoothness and the dense output torque during the rotation of the pneumatic tool are improved. Specifically, the high-pressure gas is mainly discharged from the exhaust gas flow passage 67, and the rest is discharged from the first intake flow passage 63 or the second intake flow passage 64.

To sum up, the utility model discloses a pneumatic tool, the period is passed through this at least first discrepancy gas pocket and this at least second discrepancy gas pocket and is can high-pressure gas respectively and admit air and exhaust, makes high-pressure gas flow in this air chamber in order to promote the rotor and rotate to can discharge smoothly, so high-pressure gas can smoothly flow in and discharge the air chamber and can not pile up in the air chamber, with the smooth and easy degree of rotation that promotes pneumatic tool and the output torque that is soft and close.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. A front and rear cover assembly for a pneumatic tool, comprising: the front cover and the rear cover are arranged on an axis, the front cover comprises at least one first air inlet and outlet hole, and the rear cover comprises at least one second air inlet and outlet hole; viewed from the direction of the axis, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are staggered and arranged at intervals around the axis, and the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are respectively communicated with an air supply source.

2. The utility model provides a front and back lid subassembly of pneumatic tool, supplies to locate a cylinder main part, and this cylinder main part encloses and constructs a gas chamber that supplies to hold and establish a rotor, and this cylinder main part is equipped with at least a corotation air inlet channel in one of them tip of relative two tip, and another tip is equipped with at least a reversal air inlet channel, and this air chamber is communicate respectively to this at least a corotation air inlet channel and this at least reversal air inlet channel, this front and back lid subassembly, its characterized in that includes in addition:

the front cover is arranged at one end part of the cylinder main body and comprises at least one first air inlet and outlet hole, the at least one first air inlet and outlet hole corresponds to and is communicated with one of the at least one forward air inlet channel and the at least one reverse air inlet channel, and the at least one first air inlet and outlet hole is communicated with an air supply source;

the rear cover is arranged at the opposite end part of the cylinder main body, which is provided with the front cover, and comprises at least one second air inlet and outlet hole, the at least one second air inlet and outlet hole corresponds to and is communicated with the other one of the at least one forward air inlet channel and the at least one reverse air inlet channel, the at least one second air inlet and outlet hole can be communicated with the air supply source, and the front cover and the rear cover are arranged on an axis; the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are disposed around the axis at intervals.

3. The front and rear cover assemblies for a pneumatic tool as set forth in claim 1 or 2, wherein the number of the at least one first inlet/outlet vent is two and the number of the at least one second inlet/outlet vent is two.

4. The front and rear cover assemblies for a pneumatic tool as set forth in claim 3, wherein the first inlet/outlet air holes are diagonally arranged and the second inlet/outlet air holes are diagonally arranged.

5. The front and rear cover assemblies for a pneumatic tool as set forth in claim 3, wherein the two first air inlet/outlet holes and the two second air inlet/outlet holes are alternately arranged around the axis as viewed from the axis.

6. The front and rear cover assemblies for a pneumatic tool as set forth in claim 3, wherein at least the front cover or the rear cover has an outer peripheral surface extending around the axial center line, the outer peripheral surface having a guide groove communicating with the air supply source, the guide groove being open in a radial direction and communicating with each of the first inlet/outlet holes or each of the second inlet/outlet holes.

7. The front and rear cover assemblies for a pneumatic tool as claimed in claim 6, wherein at least one of the front cover and the rear cover has at least one airtight ring portion, each of the airtight ring portions and the guide groove are arranged on the axis, and each of the airtight ring portions radially protrudes from the outer peripheral surface.

8. The front and rear cover assemblies for a pneumatic tool as set forth in claim 3, wherein the rear cover has an end surface on the axis, the end surface having a guide groove; the flow guide groove of the rear cover is communicated with the second air inlet and outlet holes and the air supply source, the second air inlet and outlet holes penetrate and open towards two opposite sides of the thickness direction of the rear cover, and the positions of the second air inlet and outlet holes correspond to the positions of the flow guide groove.

9. The front and rear cover assemblies for a pneumatic tool as set forth in claim 6, wherein the first inlet/outlet air holes are diagonally arranged, and the second inlet/outlet air holes are diagonally arranged; the two first air inlet/outlet holes and the two second air inlet/outlet holes are arranged alternately around the axis when viewed from the axis; the front cover and the rear cover are respectively provided with the peripheral surface, each first air inlet and outlet hole is provided with a first opening which is opened towards the axial lead and a second opening which is opened towards the radial direction and is arranged in the flow guide groove, and the structure of each second air inlet and outlet hole is the same as that of each first air inlet and outlet hole; the number of the at least one airtight ring part is two, and the flow guide groove is arranged between the two airtight ring parts; each airtight ring part comprises a ring groove and an airtight ring arranged in the ring groove, and the airtight ring part radially protrudes out of the ring groove.

10. A pneumatic tool, comprising:

a tool main body, including a shell and a gas supply part, the shell has an inner peripheral surface, the inner peripheral surface encloses and constructs a holding space, the shell fixes an axial, the shell passes through a first inlet channel, a second inlet channel and an exhaust channel communicating the air chamber and the outside, the inner peripheral surface has a first annular groove and a second annular groove arranged at intervals in the axial direction, the first inlet channel communicates with the first annular groove, the second inlet channel communicates with the second annular groove, the gas supply part and the shell are arranged on the axial direction, the gas supply part has two gas supply channels, the two gas supply channels each communicate with one of the first inlet channel and the second inlet channel, the two gas supply channels each communicate with a gas supply source;

the cylinder body is accommodated in the shell and encloses a gas chamber, one end of the two opposite ends of the cylinder body is provided with at least one forward air inlet channel, the other end of the cylinder body is provided with at least one reverse air inlet channel, and the at least one forward air inlet channel and the at least one reverse air inlet channel are respectively communicated with the gas chamber;

a rotor eccentrically accommodated in the air chamber;

the front cover assembly and the rear cover assembly are arranged on an axis, the front cover assembly comprises at least one first air inlet and outlet hole, the rear cover assembly comprises at least one second air inlet and outlet hole, and the at least one first air inlet and outlet hole is communicated with the at least one second air inlet and outlet hole; looking toward the axial line, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are staggered and arranged at intervals around the axial line, the at least one first air inlet/outlet hole and the at least one second air inlet/outlet hole are respectively communicated with an air supply source, the at least one first air inlet/outlet hole is communicated with the first annular groove, and the at least one second air inlet/outlet hole is communicated with the second annular groove.