A pneumatic wrench

Abstract

The present invention provides a pneumatic wrench, belonging to the technical field of pneumatic tools. It solves the technical problems that the existing pneumatic wrenches cannot adjust the gear and reversing direction with one hand. A blind hole is provided on the forward button or the reverse button of the pneumatic wrench, and a steel ball and a gear spring driving the steel ball to move outside the blind hole are provided in the blind hole. A gear plate fixedly connected to the shell is provided outside the blind hole, and gear grooves cooperating with the steel ball are arranged at intervals on the gear plate along the moving direction of the forward button or the reverse button. The present invention realizes the control of the speed and the direction of rotation by directly pressing the forward button or the reverse button through the coordination of the gear spring, the steel ball, the gear plate and the gear groove on the gear plate, and can be operated with one hand, and the complex reversing mechanism is replaced by a structure that can be reversed and adjusted with one hand, so that the structure of the pneumatic wrench is simplified and the adjustment is more convenient.

Description

Technical Field

[0001] The invention belongs to the technical field of pneumatic tools, in particular to a pneumatic wrench. Background Art

[0002] Pneumatic transmission is the evolution and development of pneumatic technology and hydraulic technology. Pneumatic transmission uses compressed air as the working medium to transmit motion and power. Since the power transmission medium of pneumatic transmission is inexhaustible air, it has little pollution, so it has broad development prospects in the field of automation. Pneumatic transmission is widely used in textile, machinery, automobile, electronics, military, steel, chemical, food, packaging and other industries. With the development of atomic energy, space technology, computer technology, etc., pneumatic transmission technology will be more widely used in various industrial fields.

[0003] Pneumatic wrenches are based on the principle of pneumatic transmission and are widely used in many industries, such as auto repair, heavy equipment maintenance, product assembly, major construction projects, installation of wire thread inserts, and anywhere else high torque output is required.

[0004] In actual use of the pneumatic wrench, one hand holds the wrench handle, and the other hand often needs to hold the locked tool. When the workpiece needs to adjust the direction of the pneumatic wrench, the existing pneumatic wrench often requires the worker to release the hand holding the workpiece, operate the reversing button to make the pneumatic wrench reverse, and then hold the workpiece to operate, which has low operating efficiency. At the same time, the reversing mechanism of the pneumatic wrench is complex, the failure rate is high, and the manufacturing cost is high, especially the one-piece cylinder, because its processing procedure is complicated, the size is difficult to control, and there is also a risk of leakage.

[0005] In order to solve the above technical problems, the invention with application number "2018214110195" discloses a pneumatic wrench, comprising: a shell, an air intake valve, a cylinder, an impact frame, a striking block and a main shaft; the air intake valve can be connected to the cylinder; the cylinder is used to drive the impact frame to rotate; the striking block is movably connected to the impact frame, and the striking block can impact the main shaft as the impact frame rotates, and can also rotate relative to the impact frame to avoid the struck part of the main shaft, and can reset and continue to rotate with the impact frame; there is only one striking block, and the air intake valve is directly connected to the cylinder.

[0006] Subsequently, based on the above-mentioned pneumatic wrench, an invention with application number "2018214844220" was applied for. The invention is achieved by arranging a forward button and a reverse button in the handle, the forward button engages with the first toothed structure on the outer wall of the intake valve to control the intake valve to rotate to the first position, and the reverse button engages with the second toothed structure on the outer wall of the intake valve to control the intake valve to rotate to the second position. The gear knob is located at the rear end of the upper body of the handle, and the cylinder is located in the upper body of the handle. A gear knob mounting groove for mounting the gear knob is provided on the end face of the cylinder, and a leakage inlet and a leakage outlet are provided on the side wall of the gear knob mounting groove. When the gear knob is rotated to different gears in the gear knob mounting groove, the opening area of ​​the leakage inlet and / or the leakage outlet is different.

[0007] Although the above-mentioned pneumatic wrench can solve the problem that it cannot be operated with one hand during forward and reverse control, when the output torque needs to be adjusted, the hand holding the workpiece still needs to be released to operate the pneumatic wrench to operate the gear knob of the pneumatic wrench, adjust it to the appropriate gear, and then hold the workpiece to operate; this directly affects the working efficiency; at the same time, the above-mentioned pneumatic wrench realizes gear control by releasing part of the gas to reduce the pressure of the high-pressure gas, so the control accuracy is low and the utilization rate of the compressed gas is not high, resulting in waste. Summary of the invention

[0008] In view of the deficiencies in the prior art, the object of the present invention is to provide a pneumatic wrench with convenient gear adjustment and high compressed gas utilization rate.

[0009] The purpose of the present invention can be achieved by the following technical solutions:

[0010] A pneumatic wrench comprises a shell, wherein the upper end of the shell is provided with a receiving cavity for accommodating a cylinder, the lower end of the shell is provided with an air intake passage connected with the receiving cavity, the air intake end face of the cylinder is arranged opposite to the upper end opening of the air intake passage, the air intake end face is symmetrically provided with a forward air intake hole and a reverse air intake hole, a reversing valve for controlling the communication of the forward air intake hole and / or the reverse air intake hole is provided in the air intake passage, a tooth-shaped protrusion is formed on the outer surface of the reversing valve, and a reversing valve extending into the shell and driving the reversing valve to rotate forward is provided at the rear end of the shell A forward button and a reverse button for driving the reversing valve to rotate in the opposite direction, the front ends of the forward button and the reverse button are both formed with a rack that meshes with the toothed protrusion, characterized in that: a blind hole is provided on the forward button or the reverse button, a steel ball and a gear spring that drives the steel ball to move outside the blind hole are provided in the blind hole, a gear plate fixed to the shell is provided outside the blind hole, and gear grooves that cooperate with the steel ball are arranged on the gear plate at intervals along the moving direction of the forward button or the reverse button, and the distance between the gear plate and the corresponding forward button or reverse button is less than the radius of the steel ball.

[0011] The pneumatic wrench cooperates with the gear spring, steel ball, gear plate and the gear slot on the gear plate, so that the speed and rotation direction can be controlled by directly pressing the forward button or the reverse button, and can be operated with one hand. The complex reversing mechanism is replaced by a structure that can be reversing and speed regulating with one hand, so that the structure of the pneumatic wrench is simplified, the adjustment is more convenient, the failure rate in use is reduced, and the cost is saved; further, the processing procedure is simplified, and the risk of air leakage of the pneumatic structure is reduced; at the same time, all compressed gas enters the cylinder through the forward air inlet hole or the reverse air inlet hole, and the utilization rate of the compressed gas is higher; further, the above-mentioned gear slot can be set in multiples as needed, generally six gears are set, forward full speed, forward high speed, forward low speed, reverse low speed, reverse high speed and reverse full speed; the above-mentioned steel ball can also be other similar structures, such as a pin with a spherical surface at one end.

[0012] In the above-mentioned pneumatic wrench, a mounting cavity with an opening facing backwards is provided in the middle of the shell, a buckle is provided in the middle of the mounting cavity to prevent the forward button and the reverse button from falling out, a second protrusion is formed on the upper side wall of the mounting cavity, the second protrusion is strip-shaped, and a limiting portion protruding in the buckle direction is formed at the rear end of the shift plate, and the front end of the limiting portion can abut against the rear end of the second protrusion, and a pressure plate protruding in the direction of the shift plate is formed at the rear end of the buckle, and the front end surface of the pressure plate can abut against the rear end of the limiting portion and fix the shift plate.

[0013] The cooperation of the limiting portion on the shift plate, the pressure plate on the buckle and the second protrusion can limit the front-to-back direction of the shift plate, thereby preventing the shift plate from shifting in the front-to-back direction after assembly, which is beneficial to improving stability.

[0014] In the above-mentioned pneumatic wrench, the front side wall of the installation cavity is provided with two through holes connected to the air inlet channel, the two through holes are symmetrically arranged on the left and right, and the front ends of the forward button and the reverse button pass through the corresponding through holes and are connected to the reversing valve.

[0015] The design of the position of the installation cavity is convenient for adjusting the gear position or direction by pressing the forward button or the reverse button with the thumb during one-handed operation.

[0016] In the above-mentioned pneumatic wrench, a first protrusion is formed on the upper side wall of the installation cavity, the lower end surfaces of the first protrusion and the second protrusion are located in the same plane, and a first slot for the buckle to slide into is formed between the first protrusion and the second protrusion, and the buckle can be inserted into the installation cavity along the first slot and fixedly connected to the shell, and limiting slots are provided on the left and right walls of the buckle, the forward button and the reverse button are arranged on the left and right sides of the buckle, and limiting blocks matching the limiting slots are provided on the side walls of the forward button and the reverse button.

[0017] The design of the upper limit groove of the above-mentioned buckle can not only guide the forward button and the reverse button, making the forward button and the reverse button more stable during movement and not offset, but also limit the forward button and the reverse button, and prevent the forward button and the reverse button from falling out through the cooperation of the limit groove and the limit block; at the same time, after the above-mentioned buckle is inserted into the first slot, it can be fixedly connected by ultrasonic welding, thereby further improving the firmness of the connection between the buckle and the shell.

[0018] In the above-mentioned pneumatic wrench, the front end of the buckle is provided with a first guide surface for facilitating the limiting block to slide into the limiting groove, and the rear end of the limiting block is provided with a second guide surface cooperating with the first guide surface.

[0019] The cooperation between the first guide surface and the second guide surface can facilitate the insertion of the forward button and the reverse button into the installation cavity during assembly.

[0020] In the above-mentioned pneumatic wrench, a mounting groove for setting a shift plate is formed between the second protrusion and the side wall of the mounting cavity, and a sliding groove connected to the mounting groove is provided on the side wall of the mounting cavity, and the shift plate can be inserted into the mounting groove from the back to the front along the sliding groove.

[0021] The above-mentioned slide groove can not only guide the shift plate to facilitate the insertion of the shift plate into the installation groove, but also fix the shift plate in the vertical direction to avoid the shift plate from changing in the vertical direction during and after assembly, thereby affecting the gear adjustment effect.

[0022] In the above-mentioned pneumatic wrench, a third clamping groove is provided at the front end of the shift plate, and a clamping protrusion cooperating with the third clamping groove is provided in the installation groove.

[0023] The cooperation between the third slot and the snap-in protrusion can realize the left-right positioning of the gear plate, avoiding the left-right displacement of the gear plate after assembly, which is beneficial to improving stability; at the same time, the third slot and the snap-in protrusion in the pneumatic wrench are both U-shaped, which can realize automatic centering and facilitate assembly.

[0024] In the above-mentioned pneumatic wrench, the forward air inlet hole and the reverse air inlet hole are both fan-shaped and arranged opposite to each other, and a vent hole is provided in the reversing valve which penetrates the reversing valve along the axis, and the upper end face of the reversing valve is sealed and fitted with the air inlet end face, and the upper end portion of the reversing valve is a semicircular vent hole outlet and a semicircular baffle, and an auxiliary exhaust groove is provided on the upper end face of the baffle, and at least one auxiliary exhaust port is provided on the side of the auxiliary exhaust groove, and the auxiliary exhaust port is located in the accommodating cavity, and the direction and speed of the rotor in the cylinder are controlled by rotating the reversing valve to control the area of ​​the forward air inlet hole and the reverse air inlet hole in the semicircular air vent hole.

[0025] The semicircular air vent design in the upper end of the reversing valve can adjust the area of ​​the forward air inlet and the reverse air inlet in the semicircular air vent by rotating the reversing valve, thereby controlling the direction and speed of the rotor in the cylinder. When the pneumatic wrench is working, when the blades on the rotor rotate to approach the forward air inlet or the reverse air inlet, the blades on the rotor are sealed and connected to the inner wall of the cylinder. For example, when rotating forward, the gas enters the cylinder from the forward air inlet and is discharged from the exhaust hole at the upper end of the cylinder. As the rotor continues to rotate, when the blades are sealed and connected to the inner wall of the cylinder, A closed cavity is formed between the outer wall of the rotor, the blades and the inner wall of the cylinder. The gas in the cavity will be compressed as the rotor continues to rotate. If the gas cannot be discharged, it will affect the continued rotation of the rotor. The design of the auxiliary exhaust groove can serve as an auxiliary exhaust. When the rotor rotates forward, the reversing air inlet hole is partially or completely connected to the auxiliary exhaust groove. The gas in the cavity can enter the auxiliary exhaust groove through the reversing air inlet hole, and then be discharged into the housing cavity of the shell through the auxiliary exhaust port arranged on the side wall of the auxiliary exhaust groove, so that the pneumatic wrench can operate normally.

[0026] In the above-mentioned pneumatic wrench, a fan-shaped stopper is provided in the vent hole, and the stopper is fixedly connected to the inner side surface of the baffle.

[0027] The design of the above-mentioned block can make the adjustment of the pneumatic wrench more precise. If no block is added, then in addition to the two situations that the forward air inlet holes are all connected to the vent holes and the reverse air inlet holes are all connected to the vent holes, both the forward air inlet holes and the reverse air inlet holes will be partially connected to the vent holes, and the simultaneous connection of the two will inevitably affect the adjustment of the gear position. For example, when you want to adjust the forward speed to be slower than the full speed but still at a faster speed, it will be difficult to adjust or even impossible to do so, because the reverse air inlet hole is also connected to the vent hole at this time, and the compressed air entering the cylinder from the reverse air inlet hole will exert a reverse force on the rotor, greatly reducing the rotation speed of the rotor, making it difficult to adjust the rotation speed of the rotor to the above-mentioned required speed. After adding the block, when the forward air inlet hole is partially blocked by the baffle, the reverse air inlet hole is still in a state of being blocked by the block, and no compressed gas enters the cylinder through the reverse air inlet hole. Therefore, the above-mentioned speed adjustment can be easily achieved.

[0028] In the above-mentioned pneumatic wrench, an exhaust hole is provided at the upper end of the cylinder, and an exhaust passage communicating with the accommodating chamber is provided in the shell.

[0029] The design of the exhaust hole and the exhaust channel can smoothly discharge the compressed gas after use. At the same time, the exhaust hole is located at the upper end of the cylinder, which can also avoid the exhaust hole from affecting the rotation of the rotor in the cylinder, and has better stability.

[0030] In the above-mentioned pneumatic wrench, the gear slot is arc-shaped and includes three first gear slots and one second gear slot which are arranged in sequence from front to back, the spacing between the three first gear slots is smaller than the distance between the second gear slot and the last first gear slot, the angle α between the rear slot wall of the first gear slot and the lower side surface of the gear plate and the angle δ between the front slot wall of the second gear slot and the lower side surface of the gear plate are in the range of 15°-30°, the angle β between the front slot wall of the first gear slot and the lower side surface of the gear plate and the angle γ between the rear slot wall of the second gear slot and the lower side surface of the gear plate are in the range of 35°-60°.

[0031] Preferably, the angle α and the angle δ are both 20°, and the angle β and the angle γ are both 45°. The design of the above-mentioned angle α and the angle δ facilitates the steel ball to slide out of the first gear slot and into the second gear slot, or to slide out of the second gear slot and into the first gear slot, while the angle β and the angle γ are designed to have a certain gear sense, which can block the steel ball to a certain extent without affecting the sliding of the steel ball, so that the user can feel a more obvious gear sense during operation, and the operation is more convenient.

[0032] In the above-mentioned pneumatic wrench, the rear end portion of the shift plate is provided with a guide groove for facilitating the steel ball to slide into the second shift groove.

[0033] The design of the guide groove can guide the steel ball when installing the forward button and the reverse button, and helps the steel ball to slide smoothly into the second gear slot.

[0034] When the present invention is working, while holding the handle at the lower end of the shell with one hand, use the thumb to push the forward button and the reverse button to drive the reversing valve to rotate forward and reverse. Relying on the elastic force changes of the steel ball, the gear spring and the gear groove on the gear plate, the size of the gear and the size of the torque output can be accurately controlled at the same time, thereby operating with one hand and freeing the other hand. Compared with the existing pneumatic wrench, the present invention combines the reversing and speed regulation functions, simplifies the product structure, saves costs and realizes single-handed operation.

[0035] Compared with the prior art, the technical effects of the present invention are:

[0036] The pneumatic wrench cooperates with the gear spring, steel ball, gear plate and the gear slot on the gear plate to realize the control of the gear position and the direction of the rotor by directly pressing the forward button or the reverse button. It can be operated with one hand, and the adjustment is more convenient. At the same time, all compressed gases enter the cylinder through the forward air inlet hole or the reverse air inlet hole, and the utilization rate of the compressed gas is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is an overall vertical sectional view of the present invention.

[0038] Figure 2It is a cross-sectional view of the forward button and the reverse button of the present invention.

[0039] Figure 3 It is a cross-sectional view of the installation cavity of the present invention.

[0040] Figure 4 It is a schematic structural diagram of the installation cavity of the present invention.

[0041] Figure 5 It is a structural schematic diagram of a cylinder of the present invention.

[0042] Figure 6 It is an exploded view of the connection structure of the forward button, the reverse button and the shift plate of the present invention.

[0043] Figure 7 It is a structural schematic diagram of the reversing valve of the present invention.

[0044] Figure 8 It is a schematic structural diagram of the buckle of the present invention.

[0045] Fig. 9 It is a schematic diagram of the overall structure of the shift plate of the present invention.

[0046] Fig.10 It is a cross-sectional view of the shift plate of the present invention.

[0047] In the figure, 1, shell; 11, accommodating chamber; 12, air inlet channel; 13, exhaust channel; 2, cylinder; 21, air inlet end face; 22, forward air inlet hole; 23, reverse air inlet hole; 24, exhaust hole; 3, reversing valve; 31, toothed protrusion; 32, vent hole; 33, baffle; 34, auxiliary exhaust groove; 35, auxiliary exhaust port; 36, block; 41, forward button; 42, reverse button; 43, rack; 44, blind hole; 45, steel ball; 46, gear spring; 47, limit block; 471, second guide surface; 5, gear plate; 51, gear slot; 511, first gear slot; 512, second gear slot; 52, third slot; 53. Limiting portion; 54. Guide groove; 6. Mounting cavity; 61. Through hole; 62. First protrusion; 63. Second protrusion; 64. First slot; 65. Mounting slot; 66. Slide slot; 67. Snap-fit ​​protrusion; 7. Buckle; 71. Limiting groove; 72. First guide surface; 73. Press plate. DETAILED DESCRIPTION

[0048] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0049] like Figure 1-10As shown, the pneumatic wrench includes a shell 1, an upper end portion of the shell 1 is provided with a receiving chamber 11 for accommodating a cylinder 2, a lower end portion of the shell 1 is provided with an air intake passage 12 connected with the receiving chamber 11, an air intake end face 21 of the cylinder 2 is arranged opposite to the upper end opening of the air intake passage 12, a forward air intake hole 22 and a reverse air intake hole 23 are symmetrically arranged on the air intake end face 21, a reversing valve 3 for controlling the communication of the forward air intake hole 22 and / or the reverse air intake hole 23 is provided in the air intake passage 12, a tooth-shaped protrusion 31 is formed on the outer surface of the reversing valve 3, and a forward button 41 extending into the shell 1 and driving the reversing valve 3 to rotate forwardly and a reverse button 42 driving the reversing valve 3 to rotate reversely are provided at the rear end of the shell 1. The front end of the forward button 41 and the reverse button 42 are both formed with a rack 43 meshing with the toothed protrusion 31, a blind hole 44 is provided on the forward button 41 or the reverse button 42, a steel ball 45 and a shift spring 46 driving the steel ball 45 to move out of the blind hole 44 are provided in the blind hole 44, a shift plate 5 fixed to the housing 1 is provided outside the blind hole 44, and shift grooves 51 cooperating with the steel ball 45 are arranged on the shift plate 5 along the moving direction of the forward button 41 or the reverse button 42 at intervals, and the distance between the shift plate 5 and the corresponding forward button 41 or reverse button 42 is less than the radius of the steel ball 45; an exhaust hole 24 is provided at the upper end of the cylinder 2, and an exhaust channel 13 connected to the accommodating chamber 11 is provided in the housing 1. The design of the exhaust hole 24 and the exhaust channel 13 can smoothly discharge the compressed gas after use, and the stability is better.

[0050] The pneumatic wrench cooperates with the gear spring 46, the steel ball 45, the gear plate 5 and the gear slot 51 on the gear plate 5, so that the speed and the direction of rotation can be controlled by directly pressing the forward button 41 or the reverse button 42, and can be operated with one hand. The complex reversing mechanism is replaced by a structure that can be reversing and regulating the speed with one hand, so that the structure of the pneumatic wrench is simplified, the adjustment is more convenient, the failure rate in use is reduced, and the cost is saved; further, the processing procedure is simplified, and the risk of air leakage of the pneumatic structure is reduced; at the same time, all compressed gas enters the cylinder 2 through the forward air inlet hole 22 or the reverse air inlet hole 23, and the utilization rate of the compressed gas is higher; further, the above-mentioned gear slot 51 can be set in multiples as needed, generally four gears are set, forward full speed, forward medium speed, forward low speed and reverse full speed; the above-mentioned steel ball 45 can also be other similar structures, such as a pin with a spherical surface at one end.

[0051] like Figure 1-4As shown, a mounting cavity 6 with an opening facing backward is provided in the middle of the shell 1, and two through holes 61 communicating with the air inlet passage 12 are provided on the front side wall of the mounting cavity 6, and the two through holes 61 are symmetrically arranged on the left and right sides. The front ends of the forward button 41 and the reverse button 42 pass through the corresponding through holes 61 and are connected to the reversing valve 3; a buckle 7 is provided in the middle of the mounting cavity 6 to prevent the forward button 41 and the reverse button 42 from falling out, and a first protrusion 62 and a second protrusion 63 are formed on the upper side wall of the mounting cavity 6, and the lower end surfaces of the first protrusion 62 and the second protrusion 63 are located in the same plane and a first groove 64 for the buckle 7 to slide into is formed between the first protrusion 62 and the second protrusion 63, and the buckle 7 can be inserted into the mounting cavity 6 along the first groove 64 and fixedly connected to the shell 1, and limiting grooves 71 are provided on the left and right walls of the buckle 7, and the forward button 41 and the reverse button 42 are arranged on the left and right sides of the buckle 7 and the side walls of the forward button 41 and the reverse button 42 are provided with limiting blocks 47 cooperating with the limiting grooves 71. The design of the position of the above-mentioned mounting cavity 6 makes it convenient for the thumb to press the forward button 41 or the reverse button 42 to adjust the gear position or direction during one-handed operation; the design of the upper limit groove 71 of the above-mentioned buckle 7 can not only guide the forward button 41 and the reverse button 42, making the forward button 41 and the reverse button 42 more stable during movement and not offset, but also limit the forward button 41 and the reverse button 42, and prevent the forward button 41 and the reverse button 42 from falling out through the cooperation of the limit groove 71 and the limit block 47; at the same time, after the above-mentioned buckle 7 is inserted into the first slot 64, it can be fixedly connected to it by ultrasonic welding, thereby further improving the firmness of the connection between the buckle 7 and the shell 1.

[0052] like Figure 2 , Figure 6 and Figure 8 As shown, the front end of the buckle 7 is provided with a first guide surface 72 for the limit block 47 to slide into the limit groove 71, and the rear end of the limit block 47 is provided with a second guide surface 471 that cooperates with the first guide surface 72. The cooperation between the first guide surface 72 and the second guide surface 471 can facilitate the insertion of the forward button 41 and the reverse button 42 into the installation cavity 6 during assembly.

[0053] like Figure 3 As shown, a mounting groove 65 for setting the shift plate 5 is formed between the second protrusion 63 and the side wall of the mounting cavity 6, and a slide groove 66 connected to the mounting groove 65 is provided on the side wall of the mounting cavity 6, and the shift plate 5 can be inserted into the mounting groove 65 from the back to the front along the slide groove 66. The above-mentioned slide groove 66 can not only guide the shift plate 5 to facilitate the insertion of the shift plate 5 into the mounting groove 65, but also fix the shift plate 5 in the vertical direction to prevent the shift plate 5 from changing in the vertical direction during and after assembly, thereby affecting the effect of the gear adjustment.

[0054] like Figure 3 , Figure 6 and Figure 8 As shown, a third card slot 52 is provided at the front end of the shift plate 5, and a card connection protrusion 67 cooperating with the third card slot 52 is provided in the mounting groove 65; the second protrusion 63 is in the shape of a strip, and a limiting portion 53 protruding toward the buckle 7 is formed at the rear end of the shift plate 5, and the front end of the limiting portion 53 can abut against the rear end of the second protrusion 63, and the rear end of the buckle 7 is formed with a pressure plate 73 protruding toward the direction of the shift plate 5, and the front end surface of the pressure plate 73 can abut against the rear end of the limiting portion 53 and fix the shift plate 5. The cooperation between the third slot 52 and the snap-in protrusion 67 can realize the left-right positioning of the shift plate 5, avoid the shift plate 5 from shifting in the left-right direction after assembly, and is beneficial to improving stability; at the same time, the third slot 52 and the snap-in protrusion 67 in the pneumatic wrench are both U-shaped, which can realize automatic centering and facilitate assembly; the cooperation between the limiting portion 53 on the shift plate 5, the pressure plate 73 on the buckle 7 and the second protrusion 63 can limit the front-to-back direction of the shift plate 5, avoid the shift plate 5 from shifting in the front-to-back direction after assembly, and is beneficial to improving stability.

[0055] like Figure 5 and Figure 6 As shown, the forward air inlet hole 22 and the reverse air inlet hole 23 are both fan-shaped and symmetrically arranged about the center of the air inlet end face 21. A vent hole 32 is provided in the reversing valve 3 which passes through the reversing valve 3 along the axis. The upper end face of the reversing valve 3 is sealed and fitted with the air inlet end face 21. The upper end portion of the reversing valve 3 is a semicircular outlet of the vent hole 32 and a semicircular baffle 33. An auxiliary exhaust groove 34 is provided on the upper end face of the baffle 33. At least one auxiliary exhaust port 35 is provided on the side of the auxiliary exhaust groove 34. The auxiliary exhaust port 35 is located in the accommodating chamber 11. The direction and speed of the rotor in the cylinder 2 are controlled by controlling the area of ​​the forward air inlet hole 22 and the reverse air inlet hole 23 in the semicircular air vent hole 32 by rotating the reversing valve 3.

[0056] The semicircular vent hole 32 in the upper end of the reversing valve 3 is designed to adjust the area of ​​the forward air inlet hole and the reverse air inlet hole 23 in the semicircular vent hole 32 by rotating the reversing valve 3, thereby controlling the direction and speed of the rotor in the cylinder 2. When the pneumatic wrench is working, when the blades on the rotor rotate to approach the forward air inlet hole 22 or the reverse air inlet hole 23, the blades on the rotor are sealed and connected to the inner wall of the cylinder 2. For example, when rotating forward, the gas enters the cylinder 2 from the forward air inlet hole 22 and is then discharged from the exhaust hole 24 at the upper end of the cylinder 2. As the rotor continues to rotate, when the blades are sealed and connected to the inner wall of the cylinder 2, the gas enters the cylinder 2 from the forward air inlet hole 22 and is discharged from the exhaust hole 24 at the upper end of the cylinder 2. When the rotor rotates forward, a closed cavity is formed between the outer wall of the rotor, the blades and the inner wall of the cylinder 2. The gas in the cavity will be compressed as the rotor continues to rotate. If the gas cannot be discharged, it will affect the continued rotation of the rotor. The design of the auxiliary exhaust groove 34 can serve as an auxiliary exhaust. When the rotor rotates forward, the reverse air inlet 23 is partially or completely connected to the auxiliary exhaust groove 34. The gas in the cavity can enter the auxiliary exhaust groove 34 through the reverse air inlet 23, and then be discharged into the accommodating cavity 11 of the shell 1 through the auxiliary exhaust port 35 provided on the side wall of the auxiliary exhaust groove 34, so that the pneumatic wrench can operate normally. In the above-mentioned pneumatic wrench, a fan-shaped block 36 is provided in the vent hole 32, and the block 36 is fixedly connected to the inner side of the baffle 33.

[0057] The design of the block 36 can make the adjustment of the pneumatic wrench more precise. If the block 36 is not added, then in addition to the two situations that the forward air inlet 22 is completely connected to the vent 32 and the reverse air inlet 23 is completely connected to the vent 32, the forward air inlet 22 and the reverse air inlet 23 will both be partially connected to the vent 32, and the simultaneous connection of the two will inevitably affect the adjustment of the gear position. For example, if you want to adjust the forward speed to be a little slower than the full speed but still at a faster speed, it will be difficult or even impossible to adjust, because At this time, the reversing air inlet 23 is also connected to the air vent 32. The compressed air entering the cylinder 2 from the reversing air inlet 23 will exert a reversing force on the rotor, greatly reducing the rotation speed of the rotor, making it difficult to adjust the rotation speed of the rotor to the required speed. After adding the block 36, when the forward air inlet 22 is partially blocked by the baffle 33, the reversing air inlet 23 is still in a state of being blocked by the block 36, and no compressed gas enters the cylinder 2 through the reversing air inlet 23. Therefore, the above-mentioned rotation speed adjustment can be easily achieved.

[0058] like Fig. 9 and Fig.10As shown, the gear groove 51 is arc-shaped and includes three first gear grooves 511 and one second gear groove 512 arranged in sequence from front to back, the spacing between the three first gear grooves 511 is smaller than the distance between the second gear groove 512 and the last first gear groove 511, the angle α between the rear groove wall of the first gear groove 511 and the lower side surface of the gear plate 5 is smaller than the angle β between the front groove wall of the first gear groove 511 and the lower side surface of the gear plate 5, the angle γ between the rear groove wall of the second gear groove 512 and the lower side surface of the gear plate 5 is greater than the angle δ between the front groove wall of the second gear groove 512 and the lower side surface of the gear plate 5; the rear end portion of the gear plate 5 is provided with a guide groove 54 for facilitating the steel ball 45 to slide into the second gear groove 512.

[0059] The above-mentioned angle α and angle δ are both about 20°, and the angle β and angle γ are both about 45°. The design of the above-mentioned angle α and angle δ makes it easy for the steel ball to slide out of the first gear slot into the second gear slot or slide out of the second gear slot into the first gear slot, while the angle β and angle γ are for having a certain gear sense, which can block the steel ball to a certain extent without affecting the sliding of the steel ball, so that the user can feel a more obvious gear sense during operation, and the operation is more convenient; the design of the above-mentioned guide groove can guide the steel ball when installing the forward button and the reverse button, which helps the steel ball to slide smoothly into the second gear slot.

[0060] When the present invention is working, while holding the handle at the lower end of the shell 1 with one hand, use the thumb to push the forward button 41 and the reverse button 42 to drive the reversing valve 3 to rotate forward and reverse. Relying on the elastic force changes of the steel ball 45, the gear spring 46 and the gear groove 51 on the gear plate 5, the size of the gear and the size of the torque output can be accurately controlled at the same time, thereby operating with one hand and freeing the other hand. Compared with the existing pneumatic wrench, the present invention combines the reversing and speed regulation functions, simplifies the product structure, saves costs, and realizes single-handed operation.

[0061] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope defined by the claims of the present invention.

Claims

1. A pneumatic wrench, comprising a housing (1), wherein the upper end of the housing (1) is provided with a receiving chamber (11) for receiving a cylinder (2), and the lower end of the housing (1) is provided with an air intake passage (12) communicating with the receiving chamber (11), an air intake end face (21) of the cylinder (2) is arranged opposite to an upper end opening of the air intake passage (12), a forward air intake hole (22) and a reverse air intake hole (23) are symmetrically arranged on the air intake end face (21), and a positive air intake hole (22) and a reverse air intake hole (23) are arranged in the air intake passage (12) for controlling the forward and reverse air intake holes. A reversing valve (3) connected to a rotating air inlet (22) and / or a reverse air inlet (23), wherein a tooth-shaped protrusion (31) is formed on the outer surface of the reversing valve (3), and a forward button (41) extending into the housing (1) and driving the reversing valve (3) to rotate in a forward direction and a reverse button (42) driving the reversing valve (3) to rotate in a reverse direction are provided at the rear end of the housing (1), and a rack (43) meshing with the tooth-shaped protrusion (31) is formed at the front end of the forward button (41) and the reverse button (42), wherein: The forward button (41) or the reverse button (42) is provided with a blind hole (44), a steel ball (45) and a shift spring (46) for driving the steel ball (45) to move out of the blind hole (44) are provided in the blind hole (44), a shift plate (5) fixedly connected to the housing (1) is provided outside the blind hole (44), and shift grooves (51) for cooperating with the steel ball (45) are provided on the shift plate (5) at intervals along the moving direction of the forward button (41) or the reverse button (42); A mounting cavity (6) with an opening facing backwards is provided in the middle of the mounting cavity (6), a buckle (7) for preventing the forward button (41) and the reverse button (42) from falling out is provided in the middle of the mounting cavity (6), a second protrusion (63) is formed on the upper side wall of the mounting cavity (6), the second protrusion (63) is in a strip shape, a limiting portion (53) protruding in the direction of the buckle (7) is formed at the rear end of the shift plate (5), the front end of the limiting portion (53) is capable of abutting against the rear end of the second protrusion (63), and a pressure plate (73) protruding in the direction of the shift plate (5) is formed at the rear end of the buckle (7), the front end surface of the pressure plate (73) is capable of abutting against the rear end of the limiting portion (53) and fixing the shift plate (5).

2. A pneumatic wrench according to claim 1, characterized in that: The front side wall of the installation cavity (6) is provided with two through holes (61) communicating with the air inlet passage (12), the two through holes (61) being arranged symmetrically, the front ends of the forward button (41) and the reverse button (42) passing through the corresponding through holes (61) and connected to the reversing valve (3); the upper side wall of the installation cavity (6) is formed with a first protrusion (62), the lower end surfaces of the first protrusion (62) and the second protrusion (63) are located in the same plane, and the first protrusion (62) and the second protrusion (63) are arranged in a substantially parallel relationship. A first slot (64) is formed between the blocks (63) for the buckle (7) to slide into, and the buckle (7) can be inserted into the installation cavity (6) along the first slot (64) and fixedly connected to the shell (1). The left and right walls of the buckle (7) are both provided with limit slots (71). The forward button (41) and the reverse button (42) are arranged on the left and right sides of the buckle (7), and the side walls of the forward button (41) and the reverse button (42) are both provided with limit blocks (47) that cooperate with the limit slots (71).

3. A pneumatic wrench according to claim 2, characterized in that: The front end of the buckle (7) is provided with a first guide surface (72) for facilitating the limiting block (47) to slide into the limiting groove (71), and the rear end of the limiting block (47) is provided with a second guide surface (471) that cooperates with the first guide surface (72).

4. A pneumatic wrench according to claim 2, characterized in that: A mounting groove (65) for arranging the shift plate (5) is formed between the second protrusion (63) and the side wall of the mounting cavity (6); a slide groove (66) communicating with the mounting groove (65) is provided on the side wall of the mounting cavity (6); and the shift plate (5) can be inserted into the mounting groove (65) through the slide groove (66) from the back to the front.

5. A pneumatic wrench according to claim 4, characterized in that: A third clamping groove (52) is provided at the front end of the shifting plate (5), and a clamping protrusion (67) cooperating with the third clamping groove (52) is provided in the mounting groove (65).

6. A pneumatic wrench according to any one of claims 1 to 5, characterized in that: The forward air inlet (22) and the reverse air inlet (23) are both fan-shaped and arranged opposite to each other. The reversing valve (3) is provided with an air vent (32) that penetrates the reversing valve (3) along the axis. The upper end surface of the reversing valve (3) is sealed and fitted with the air inlet end surface (21). The upper end of the reversing valve (3) is a semicircular outlet of the air vent (32) and a semicircular baffle (33). The upper end surface of the baffle (33) is provided with an auxiliary exhaust groove (34). The side of the auxiliary exhaust groove (34) is provided with an auxiliary exhaust port (35). The auxiliary exhaust port (35) is located in the accommodating chamber (11). The direction and speed of the rotor in the cylinder (2) are controlled by rotating the reversing valve (3) to control the area of ​​the forward air inlet (22) and the reverse air inlet (23) in the semicircular air vent (32).

7. A pneumatic wrench according to claim 6, characterized in that: A fan-shaped stopper (36) is provided in the vent hole (32), and the stopper (36) is fixedly connected to the inner side surface of the baffle (33).

8. A pneumatic wrench according to any one of claims 1 to 5, characterized in that: The gear slot (51) is arc-shaped and comprises three first gear slots (511) and one second gear slot (512) arranged in sequence from front to back, the angle α between the rear slot wall of the first gear slot (511) and the lower side surface of the gear plate (5) and the angle δ between the front slot wall of the second gear slot (512) and the lower side surface of the gear plate (5) are in the range of 15°-30°, the angle β between the front slot wall of the first gear slot (511) and the lower side surface of the gear plate (5) and the angle γ between the rear slot wall of the second gear slot (512) and the lower side surface of the gear plate (5) are in the range of 35°-60°.

9. A pneumatic wrench according to claim 8, characterized in that: The rear end of the shift plate (5) is provided with a guide groove (54) for facilitating the steel ball (45) to slide into the second shift groove (512).

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