Air chamber on-off control device of air spring type electric tool

Abstract

An air chamber on-off control device of an air spring type electric tool comprises an air cylinder shell and an energy storage device shell, a first air chamber is formed in the air cylinder shell, a second air chamber is formed in the energy storage device shell, a piston firing pin assembly capable of axially moving is arranged in the air cylinder shell, and a lifting wheel and a locking assembly are arranged on the two sides of the motion path of a firing pin respectively. The lifting wheel and the locking assembly are both controlled by a motor, an opening and closing valve and a jacking spring are further arranged on one side of the end, connected with the energy storage device shell, of the air cylinder shell, the opening and closing valve blocks the end face of the air cylinder shell under the action of the jacking spring, so that the first air chamber is separated from the second air chamber, a driving rod is further arranged in the energy storage device shell, and the driving rod is connected with the energy storage device shell. One end of the driving rod is connected with the opening and closing valve to form a synchronous moving structure, and the other end of the driving rod extends out of the energy accumulator shell; the opening and closing of the first air chamber and the second air chamber are controlled by the movement of the opening and closing valve, and when the piston firing pin assembly is in the upper stop position, the opening and closing valve blocks the end face of the air cylinder shell, so that the service life of the product is longer, and the safety is higher.

Description

Technical Field

[0001] The utility model relates to an air chamber on-off control device for a pneumatic spring type electric tool. Background Art

[0002] Pneumatic spring type electric tools are very common in the market. Its structure includes a cylinder housing and an energy storage housing. A first air chamber is formed inside the cylinder housing, and a second air chamber is formed inside the energy storage housing. The gas between the first air chamber and the second air chamber always remains in a connected state. In addition, an axially movable piston striker assembly is provided inside the cylinder housing. On one side of the movement path of the striker, there is a lifting wheel, and on the other side, there is a locking assembly. Both the lifting wheel and the locking assembly are controlled by a motor; its nailing cycle is as follows: when the piston striker assembly is at the top dead center (ready state), the locking assembly locks the striker, the motor controls the locking assembly to unlock, and the high-pressure gas in the second air chamber of the energy storage housing pushes the piston striker assembly to move to achieve nailing. The piston striker assembly moves from the top dead center to the bottom dead center (firing state). After the piston striker assembly reaches the bottom dead center, the motor controls the lifting wheel to rotate, and the rotation of the lifting wheel drives the piston striker assembly to move from the bottom dead center to the top dead center again, that is, the piston striker assembly is reset. After that, the locking assembly locks the striker again.

[0003] For a pneumatic spring type electric nail gun with a conventional structure, since the first air chamber and the second air chamber always remain in a connected state, the energy storage always gives a certain air pressure to the piston striker assembly. Especially at the top dead center, because the gas is extremely compressed, the air pressure value at this time is very high. Relying on the locking assembly to give a locking force laterally to the striker, there are always relatively large stressed parts in the locking assembly that are prone to fatigue damage. In addition, when the locking assembly fails abnormally, the striker will be fired quickly, posing a certain safety hazard. Summary of the Invention

[0004] In view of the deficiencies existing in the above problems, the utility model provides an air chamber on-off control device for a pneumatic spring type electric tool.

[0005] To achieve the above object, the present utility model provides a gas chamber on-off control device for a gas spring type electric tool, which includes a cylinder housing and an accumulator housing fixed relative to the cylinder housing. The right sides of the cylinder housing and the accumulator housing are both closed by end caps. A first gas chamber is formed inside the cylinder housing, and a second gas chamber is formed inside the accumulator housing. A piston striker assembly that can move axially is provided inside the cylinder housing. The piston striker assembly includes a piston and a striker fixedly connected. On both sides of the movement path of the striker, a lifting wheel and a locking assembly are respectively provided. The lifting wheel and the locking assembly are both controlled by a motor. On one side of the connection end between the cylinder housing and the accumulator housing, an on-off valve and a holding spring are further provided. The on-off valve blocks the end face of the cylinder housing under the action of the holding spring, so that the first gas chamber is separated from the second gas chamber. A driving rod is further provided inside the accumulator housing. One end of the driving rod is connected to the on-off valve to form a synchronous movement structure, and the other end of the driving rod extends outside the accumulator housing.

[0006] Further, the accumulator housing is connected to the cylinder housing through a connecting member. The second gas chamber includes an upper chamber located outside the cylinder housing and a lower chamber located on the other side outside the cylinder housing. The upper chamber and the lower chamber always remain in a communicating state. A counterbore is provided at one end of the on-off valve, and a through hole communicating with the second gas chamber is provided on the wall of the counterbore.

[0007] Further, the driving rod is located in the upper chamber. The driving rod includes a split rod a and rod b. The rod a includes an integrally formed bent portion, and the bent portion is clamped into the annular groove of the on-off valve to form a synchronous movement structure.

[0008] Further, a first cam and a second cam that rotate synchronously are further provided on the output shaft of the motor. The first cam is in transmission connection with the driving rod through a transmission rod, and the second cam is in linkage with the locking assembly through a transmission component to realize the locking and unlocking control of the striker.

[0009] Further, the first cam and the second cam are an integral part, and the radial displacement of the second cam from the center line X of the output shaft is greater than the radial displacement of the first cam from the center line X of the output shaft.

[0010] Further, one end of the transmission rod is fixedly connected to the rod b through a fastener, and the other end of the transmission rod is provided with a roller. During the process of the on-off valve opening to the maximum stroke, the roller and the first cam always remain in contact.

[0011] Further, a sealing ring is provided on the rod b, and the sealing ring seals the upper chamber from the outside. At the same time, a bolt is provided on the energy storage housing, and the bolt restricts the movement position of the rod b.

[0012] Further, a support spring is also arranged on the rod b, and the two ends of the support spring act between the transmission rod and the energy storage housing respectively.

[0013] The beneficial effects of the present utility model compared with the prior art are as follows: The on-off of the first air chamber and the second air chamber is controlled by the movement of the on-off valve. When the piston striker assembly is at the top dead center, the on-off valve seals the end face of the cylinder housing. The piston striker assembly only receives the internal energy of the compressed gas in the first air chamber. The gas volume in the first air chamber is small, and the generated internal energy is small. The initial kinetic energy of the accidental firing caused by the failure of the parts of the piston striker assembly is small. The piston striker assembly moves a short distance along the axis, and the striker stops before contacting the driving fastener, avoiding accidental injury. The product has a longer service life and higher safety. Description of the Drawings

[0014] Figure 1 is a three-dimensional view of the air chamber on-off control device of the gas spring type electric tool involved;

[0015] Figure 2 is an internal structure diagram of the air chamber on-off control device of the gas spring type electric tool involved;

[0016] Figure 3 is a schematic diagram of the driving rod involved;

[0017] Figure 4 is a schematic diagram of the transmission rod involved;

[0018] Figure 5 is a schematic diagram of the integrated first cam and second cam involved;

[0019] Figure 6 is a cross-sectional view of the air chamber on-off control device of the gas spring type electric tool (ready state);

[0020] Figure 7 is a cross-sectional view of the air chamber on-off control device of the gas spring type electric tool (on-off valve open);

[0021] Figure 8 is a cross-sectional view of the air chamber on-off control device of the gas spring type electric tool (locking assembly unlocked);

[0022] Figure 9 is a cross-sectional view of the air chamber on-off control device of the gas spring type electric tool (firing state).

[0023] In the figure: 1. Motor; 2. Locking assembly; 3. Lifting wheel; 4. First cam; 5. Second cam; 6. Piston striker assembly; 61. Striker; 62. Piston; 7. Roller; 8. Transmission rod; 9. Support spring; 10. Drive rod; 101. Rod a; 1011. Bending part; 102. Rod b; 103. Sealing ring; 11. Cylinder housing; 111. First air chamber; 12. Connector; 13. Energy storage housing; 131. Second air chamber; 1311. Upper chamber; 1312. Lower chamber; 14. Opening and closing valve; 141. Ring groove; 142. Communication hole; 15. Supporting spring; 16. End cover; 17. Plug Detailed implementation mode

[0024] As Figures 1-9 shown, a device for controlling the on-off of the air chamber of a pneumatic spring type electric tool according to an embodiment of the present invention includes a cylinder housing 11 and an energy storage housing 13 fixed relative to the position of the cylinder housing 11. The right sides of the cylinder housing 11 and the energy storage housing 13 are both closed by an end cover 16. A first air chamber 111 is formed inside the cylinder housing 11, and a second air chamber 131 is formed inside the energy storage housing 13. A piston striker assembly 6 that can move axially is provided inside the cylinder housing 11. The piston striker assembly 6 includes a piston 62 and a striker 61 fixedly connected. A lifting wheel 3 and a locking assembly 2 are respectively provided on both sides of the movement path of the striker 61. The lifting wheel 3 and the locking assembly 2 are both controlled by a motor 1 (the transmission method between the lifting wheel 3, the locking assembly 2 and the motor 1 is part of the prior art and will not be described in detail in this application). An opening and closing valve 14 and a supporting spring 15 are also provided on one side of the connection end of the cylinder housing 11 and the energy storage housing 13. The opening and closing valve 14 blocks the end face of the cylinder housing 11 under the action of the supporting spring 15, so that the first air chamber 111 is separated from the second air chamber 131. A drive rod 10 is also provided inside the energy storage housing 13. One end of the drive rod 10 is connected to the opening and closing valve 14 to form a synchronous movement structure. The other end of the drive rod 10 extends outside the energy storage housing 13. See Figure 9, the right side of the piston 62 inside the cylinder housing 11 is defined as the first air chamber 111, and the size of the first air chamber 111 changes with the change of the position of the piston 62; the energy storage housing 13 is connected to the cylinder housing 11 through the connecting member 12. For the convenience of connection, the connecting member 12 and the cylinder housing 11 are preferably screwed together. The second air chamber 131 includes an upper chamber 1311 located outside the cylinder housing 11 and a lower chamber 1312 located on the other side outside the cylinder housing 11. The upper chamber 1311 and the lower chamber 1312 are always in a communicating state. One end of the opening and closing valve 14 is provided with a counterbore, and a through hole 142 communicating with the second air chamber 131 is provided on the wall of the counterbore (during the opening process of the opening and closing valve 14, the exhaust function is realized through the communication hole 142); the driving rod 10 is located in the upper chamber 1311. For the convenience of processing and assembly, the driving rod 10 includes a split rod a101 and rod b102. The rod a101 includes an integral bending portion 1011, and the bending portion 1011 is snapped into the annular groove 141 of the opening and closing valve 14 to form a synchronous movement structure. The other end of the rod a101 away from the bending portion 1011 is connected to the rod b102 in a stacked manner, that is, the rod b102 is stacked above the rod a101 to play a limiting role on the rod a101; a first cam 4 and a second cam 5 that rotate synchronously are also provided on the output shaft of the motor 1. The first cam 4 is in transmission connection with the driving rod 10 through a transmission rod 8, and the second cam 5 is in linkage with the locking assembly 2 through a transmission assembly to realize the locking and unlocking control of the striker 61; when the machine starts, the motor 1 drives the output shaft to rotate, first making the first cam 4 act on the roller 7 to move towards the opening and closing valve 14 until the opening and closing valve 14 is in the open mode. After synchronous rotation, the second cam 5 touches the transmission assembly, and through the transmission assembly and the locking assembly 2, the striker 61 is unlocked. The piston striker assembly 6 runs from the top dead center to the bottom dead center. During this time period, as the output shaft rotates, the first cam 4 touches the roller 7, and the roller 7 continues to move towards the opening and closing valve 14, causing the opening and closing valve 14 to run to the maximum stroke open position until the roller 7 is separated from the first cam 4. The roller 7 moves in the opposite direction of the opening and closing valve 14 to reset, and the opening and closing valve 14 moves towards the end face of the cylinder housing 11 to reach the end face of the cylinder housing 11, and the first air chamber 111 is separated from the second air chamber 131, and the roller 7 is no longer in contact with the first cam 4; the output shaft of the motor 1 rotates, and the lifting wheel 3 drives the piston striker assembly 6 from the bottom dead center to the top dead center. During this process, the volume of the first air chamber 111 gradually decreases, and the gas pressure gradually increases until the pressure pushes the opening and closing valve 14 to move away from the end face of the cylinder housing 11, and the gas in the first air chamber 111 flows into the second air chamber 131 until the pressures of the first air chamber 111 and the second air chamber 131 are equal. Under the push of the holding spring 15, the opening and closing valve 14 returns to the end face of the cylinder housing 11, and the first air chamber 111 is separated from the second air chamber 131, and the roller 7 has no contact with the first cam 4;For the convenience of processing and forming, the first cam 4 and the second cam 5 are an integral part. The radial displacement of the second cam 5 from the center line X of the output shaft is greater than that of the first cam 4 from the center line X of the output shaft. One end of the transmission rod 8 is fixedly connected to the rod b102 through a fastener, and the other end of the transmission rod 8 is provided with a roller 7. During the process of the on-off valve 14 opening to the maximum stroke, the roller 7 is always in contact with the first cam 4. A sealing ring 103 is provided on the rod b102, and the sealing ring 103 forms a seal between the upper chamber 1311 and the outside. At the same time, a pin 17 is provided on the energy storage housing 13, and the pin 17 limits the movement position of the rod b102. A support spring 9 is also arranged on the rod b102, and both ends of the support spring 9 act between the transmission rod 8 and the energy storage housing 13 respectively.

[0025] The on-off of the first air chamber and the second air chamber is controlled by the movement of the on-off valve. When the piston striker assembly is at the top dead center, the on-off valve blocks the end face of the cylinder housing. The piston striker assembly only receives the internal energy of the compressed gas in the first air chamber. The gas volume in the first air chamber is small, and the generated internal energy is small. The initial kinetic energy of the accidental firing caused by the component failure of the piston striker assembly is small. The piston striker assembly moves a small distance along the axis, and the striker stops before contacting the driving fastener, avoiding accidental injury. The product has a longer service life and higher safety.

[0026] During specific use, for the convenience of understanding the present invention, it is described in conjunction with the accompanying drawings.

[0027] See Figure 6 , at this time it is in the standby state, and the locking assembly 2 locks the striker 61. At this time, because the on-off valve 14 blocks the end face of the cylinder housing 11, the first air chamber 111 and the second air chamber 131 are not conducted, and the striker 61 is not affected by the air pressure in the second air chamber 131.

[0028] See Figure 7 , during the rotation of the motor 1, the first cam 4 and the second cam 5 are driven to rotate synchronously. Among them, the first cam 4 first contacts and acts on the roller 7, causing the transmission rod 8 and the driving rod 10 to move synchronously to the right axially. Therefore, the on-off valve 14 also moves synchronously to the right, making the first air chamber 111 and the second air chamber 131 conduct, and the striker 61 is affected by the air pressure in the second air chamber 131.

[0029] See Figure 8 , when the motor 1 continues to rotate, the process of the roller 7 relative to the first cam 4 remains unchanged, that is, the on-off valve 14 remains in the open state. The second cam 5 acts on the locking assembly 2 through the transmission component, causing the locking assembly 2 to unlock the striker 61.

[0030] See Figure 9After the locking assembly 2 unlocks the firing pin 61, the air pressure causes the firing pin 61 to be fired, and the firing pin 61 moves from the top dead center to the bottom dead center; thereafter, the roller 7 disengages from the first cam 4, causing the on-off valve 14 to reset under the action of the biasing spring 15, that is, the on-off valve 14 blocks the end face of the cylinder housing 11 again, and the first air chamber 111 and the second air chamber 131 are blocked again;

[0031] Thereafter, the lifting wheel 3 drives the firing pin 61 to reset to the top dead center and return to the initial state.

[0032] This patent application does not limit or elaborate on the contour shape and stroke dimensions of the first cam 4 and the second cam 5. During specific design, as long as the sequence of actions during the nailing process is satisfied, that is, the on-off valve 14 is first opened and then the unlocking assembly 2 is unlocked.

[0033] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An air chamber on-off control device for a gas spring type electric tool, comprising a cylinder housing (11) and an accumulator housing (13) fixed relative to the cylinder housing (11), the right sides of the cylinder housing (11) and the accumulator housing (13) being sealed by an end cover (16), a first air chamber (111) being formed inside the cylinder housing (11), and a second air chamber (131) being formed inside the accumulator housing (13), an axially movable piston striker assembly (6) being provided inside the cylinder housing (11), the piston striker assembly (6) comprising a piston (62) and a striker (61) being fixedly connected, a lifting wheel (3) and a locking assembly (2) being provided on both sides of a movement path of the striker (61), the lifting wheel (3) and the locking assembly (2) being controlled by a motor (1), characterized in that: An on-off valve (14) and a holding spring (15) are also provided on one side of the connection end between the cylinder housing (11) and the energy accumulator housing (13); the on-off valve (14) blocks the end surface of the cylinder housing (11) under the action of the holding spring (15), so that the first air chamber (111) is separated from the second air chamber (131); a driving rod (10) is also provided in the energy accumulator housing (13); one end of the driving rod (10) is connected to the on-off valve (14) to form a synchronous movement structure, and the other end of the driving rod (10) extends out of the energy accumulator housing (13).

2. The air chamber on-off control device of a gas spring type electric tool according to claim 1, characterized in that: The energy accumulator housing (13) is connected to the cylinder housing (11) via a connecting piece (12); the second air chamber (131) comprises an upper chamber (1311) located outside the cylinder housing (11) and a lower chamber (1312) located on the other side of the cylinder housing (11); the upper chamber (1311) and the lower chamber (1312) are always connected; a countersunk hole is provided at one end of the on-off valve (14); a through hole (142) connected to the second air chamber (131) is provided on a wall of the countersunk hole.

3. The air chamber on-off control device of a gas spring type electric tool according to claim 2, characterized in that: The driving rod (10) is located in the upper chamber (1311), and the driving rod (10) comprises a separate rod a (101) and a rod b (102). The rod a (101) comprises an integral bending portion (1011), and the bending portion (1011) is inserted into the annular groove (141) of the opening and closing valve (14), thereby forming a synchronous movement structure.

4. The air chamber on-off control device of a gas spring type electric tool according to claim 3, characterized in that: A first cam (4) and a second cam (5) which rotate synchronously are also provided on the output shaft of the motor (1); the first cam (4) is in transmission connection with the drive rod (10) via a transmission rod (8); and the second cam (5) is in linkage with the locking assembly (2) via a transmission assembly, so as to realize locking and unlocking control of the striker (61).

5. The air chamber on-off control device of a gas spring type electric tool according to claim 4, characterized in that: The first cam (4) and the second cam (5) are an integral part, and the radial displacement of the second cam (5) to the center line X of the output shaft is greater than the radial displacement of the first cam (4) to the center line X of the output shaft.

6. The air chamber on-off control device of a gas spring type electric tool according to claim 4 or 5, characterized in that: One end of the transmission rod (8) is fixedly connected to the rod b (102) via a fastener, and the other end of the transmission rod (8) is provided with a roller (7). When the on-off valve (14) is opened to a maximum stroke, the roller (7) and the first cam (4) always maintain a contact state.

7. The air chamber on-off control device of a gas spring type electric tool according to claim 6, characterized in that: The rod b (102) is provided with a sealing ring (103), and the sealing ring (103) forms a seal between the upper chamber (1311) and the outside world. At the same time, the energy storage device housing (13) is provided with a latch (17), and the latch (17) limits the movable position of the rod b (102).

8. The air chamber on-off control device of a gas spring type electric tool according to claim 7, characterized in that: A support spring (9) is also arranged on the rod b (102), and two ends of the support spring (9) act respectively between the transmission rod (8) and the energy storage housing (13).

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