Shock absorber

Abstract

The shock absorber comprises a piston assembly, and a control oil cavity, an overflow block, a valve element and an oil discharging channel are arranged in the piston assembly; valves are arranged between the control oil cavity and the rod cavity and between the control oil cavity and the rodless cavity; the valve element is sequentially provided with a large-diameter section and a small-diameter section in the axial direction of the valve element. The overflow block is of an annular structure with a hollow part, the valve element is arranged in the hollow part of the overflow block in the mode of being capable of moving in the axial direction, a first oil channel is formed between the small-diameter section and the side wall of the hollow part, and a first overflow hole communicating with the first oil channel and the control oil cavity is formed in the side wall of the overflow block. A second overflow hole communicated with the oil discharge channel is further formed in the side wall of the overflow block; the valve element can be switched between a first position and a second position in a sliding mode in the axial direction. According to the shock absorber provided by the invention, the problem of pollution caused by easy leakage of oil can be avoided.

Description

Technical Field

[0001] The invention relates to a shock absorber. Background Art

[0002] The shock absorber is an important component of the vehicle chassis system, which can effectively buffer the vibration of the vehicle chassis. The shock absorber includes a cylinder, a piston assembly, and a piston rod connected to the piston assembly. The piston assembly is in a sealed fit with the inner wall of the cylinder, thereby dividing the space of the cylinder into a first working space and a second working space, and the piston rod is located in one of the working spaces. The piston assembly includes a piston body, a valve group connected to the piston body, and an oil circuit arranged on the piston body.

[0003] The oil circuit can connect the first working space and the second working space, and the valve group is used to control the opening and closing of the oil circuit. When the piston body moves up and down in the cylinder, the valve group controls the oil in the first working space and the second working space to flow back and forth through the oil circuit. At this time, the oil in the oil circuit will damp the movement of the piston body, thereby playing a role in shock absorption.

[0004] The valve group includes devices such as a solenoid, a valve seat and a valve core. A magnetic field force can be generated by passing an electric current through the solenoid, and under the action of the magnetic field force, the valve core forms a certain damping force on the oil.

[0005] Due to structural limitations of the valve group structure in the prior art, a relatively large radial clearance needs to be reserved between the valve core and the valve seat in the radial direction, which may cause oil leakage and contamination. Summary of the invention

[0006] The object of the present invention is to provide a shock absorber which can avoid the problem of oil leakage causing pollution.

[0007] The shock absorber provided by the present invention comprises a cylinder and a piston assembly, wherein the piston assembly divides the cylinder into a rod chamber and a rodless chamber, and a control oil chamber, an overflow block, a valve core, and an oil unloading channel are arranged inside the piston assembly; wherein,

[0008] Valves are provided between the control oil chamber and the rod chamber and the rodless chamber;

[0009] The valve core is provided with a large diameter section and a small diameter section in sequence along its axial direction, and the diameter of the large diameter section is larger than the diameter of the small diameter section;

[0010] The overflow block is an annular structure with a hollow portion, the valve core is axially displaceably arranged in the hollow portion of the overflow block, and a first oil passage is formed between the small diameter section and the side wall of the hollow portion, a first overflow hole communicating with both the first oil passage and the control oil chamber is arranged on the side wall of the overflow block, and a second overflow hole communicating with the oil unloading passage is also arranged on the side wall of the overflow block; wherein,

[0011] The valve core can slide and switch axially between a first position and a second position. In the first position, the large diameter section of the valve core separates the first oil channel and the second overflow hole. In the second position, the first oil channel is connected to the second overflow hole.

[0012] According to the shock absorber provided by the present invention, the second overflow holes are provided in plurality and are evenly distributed along the circumference of the overflow block.

[0013] According to the shock absorber provided by the present invention, a first overflow channel is provided in the piston assembly, and the first overflow channel connects the rod chamber and the rodless chamber.

[0014] According to the shock absorber provided by the present invention, the hollow portion of the overflow block includes a large diameter portion and a small diameter portion, the first oil channel is formed between the side wall of the large diameter portion and the small diameter section of the valve core; the small diameter portion is sealed and matched with the small diameter section of the valve core.

[0015] According to the shock absorber provided by the present invention, the piston assembly is provided with a second overflow channel connected to the small diameter portion and the rodless chamber, and a port of the second overflow channel connected to the small diameter portion corresponds to the lower end of the valve core.

[0016] According to the shock absorber provided by the present invention, the piston assembly is provided with a first oil circuit, a second oil circuit, a third oil circuit and a fourth oil circuit; wherein,

[0017] One end of the first oil circuit and the second oil circuit is connected to the rod chamber, the other end of the first oil circuit is connected to the control oil chamber, and the other end of the second oil circuit is connected to the second port of the oil unloading channel; one end of the third oil circuit and the fourth oil circuit is connected to the rodless chamber, the other end of the third oil circuit is connected to the control oil chamber, and the other end of the fourth oil circuit is connected to the second port of the oil unloading channel.

[0018] According to the shock absorber provided by the present invention, the valve includes a first one-way valve and a third one-way valve, and the piston assembly also includes a second one-way valve and a fourth one-way valve, wherein the first one-way valve, the second one-way valve, the third one-way valve and the fourth one-way valve are respectively arranged in one-to-one correspondence with the first oil circuit, the second oil circuit, the third oil circuit and the fourth oil circuit;

[0019] When the oil pressure in the rod chamber is greater than the oil pressure in the control oil chamber, and the oil pressure in the control oil chamber is greater than the oil pressure in the rodless chamber, the first one-way valve and the fourth one-way valve are connected; when the oil pressure in the rodless chamber is greater than the oil pressure in the control oil chamber, and the oil pressure in the control oil chamber is greater than the oil pressure in the rod chamber, the third one-way valve and the second one-way valve are connected.

[0020] According to the shock absorber provided by the present invention, the second oil passage and the fourth oil passage pass through the axis of the valve core.

[0021] The shock absorber provided by the present invention comprises a cylinder and a piston assembly. It should be noted that the piston assembly comprises a piston body, a piston ring, various valve structures connected to the piston body, and other components connected to the piston body and reciprocating with the piston body. The piston assembly is connected to the piston rod through a connecting structure, and the piston assembly divides the cylinder into a rod chamber and a rodless chamber. A control oil chamber, an overflow block, a valve core and an oil unloading channel are arranged inside the piston assembly; wherein valves are arranged between the control oil chamber and the rod chamber and the rodless chamber; the valve core is provided with a large diameter section and a small diameter section in sequence along its axial direction, and the diameter of the large diameter section is larger than the diameter of the small diameter section; the overflow block is an annular structure with a hollow portion, and the valve core can be axially displaced in the hollow portion of the overflow block, and a first oil channel is formed between the small diameter section and the side wall of the hollow portion, and a first overflow hole connected to the first oil channel and the control oil chamber is arranged on the side wall of the overflow block, and a second overflow hole connected to the oil unloading channel is also arranged on the side wall of the overflow block; wherein the valve core can slide and switch between a first position and a second position along the axial direction, and in the first position, the large diameter section of the valve core separates the first oil channel and the second overflow hole, and in the second position, the first oil channel is connected to the second overflow hole. It should be noted that when the shock absorber is in a non-working state, the oil pressure in the rod chamber and the rodless chamber is in a balanced state, and the valve core is kept in the first position under the magnetic field force generated by the solenoid, directly isolating the first oil channel and the second overflow hole. When the shock absorber is in a compression stroke, the oil pressure in the rodless chamber increases, and the oil in the rodless chamber enters the control oil chamber through the valve, the oil pressure in the control oil chamber increases, and enters the first oil channel through the first overflow hole, and the oil pressure acts on the stepped surface formed by the large diameter section and the small diameter section of the valve core, thereby pushing the valve core to overcome the magnetic field force and axially displace to the second position. At this time, the first oil channel is connected to the second overflow hole, and the oil in the first oil channel enters the oil unloading channel through the second overflow hole, and enters the rod chamber through the oil unloading channel, thereby realizing the damping effect of the shock absorber. When the shock absorber is in the rebound stroke, the oil pressure in the rod chamber increases, and the oil in the rod chamber enters the control oil chamber through the valve, the oil pressure in the control oil chamber increases, and enters the first oil channel through the first overflow hole, and the oil pressure acts on the step surface formed by the large diameter section and the small diameter section of the valve core, thereby pushing the valve core to overcome the magnetic field force and axially displace to the second position. At this time, the first oil channel is connected to the second overflow hole, and the oil in the first oil channel enters the oil unloading channel through the second overflow hole, and enters the rodless chamber through the oil unloading channel, thereby realizing the damping effect of the shock absorber. Obviously, the present invention forms a sliding valve structure by setting the valve core to a sliding form, and realizes the on-off control of the oil circuit by cooperating with the overflow block. The sliding valve structure has good stability and can effectively avoid the problem of oil leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. 4 is a schematic cross-sectional view of a piston assembly according to an embodiment of the present invention.

[0023] Figure 2 FIG. 1 is a partial cross-sectional schematic diagram of a piston assembly according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following detailed description and drawings are used to illustrate the principle of the present invention. The present invention is not limited to the preferred embodiments described. The protection scope of the present invention is defined by the claims.

[0025] It should be noted that the orientations or positional relationships indicated in this specification are based on the orientations or positional relationships described in the accompanying drawings and are only for the convenience and simplification of description, and do not indicate or imply that the device referred to must have a specific orientation or be constructed in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0026] Please refer to Figure 1-Figure 2 The shock absorber provided in this embodiment includes a cylinder and a piston assembly 1. The piston assembly 1 is provided with a control oil chamber 11, an overflow block 23, a solenoid, a valve core 28, an oil discharge channel 15, etc. The solenoid can generate a magnetic field when current is passed through it, and the valve core 28 is acted upon by the magnetic field force.

[0027] The piston assembly 1 is connected to the piston rod through a connecting structure, the piston body of the piston assembly 1 is sealed with the inner wall of the cylinder, and the piston assembly 1 can slide along the axial direction of the cylinder. The piston assembly 1 divides the cylinder into a rod chamber and a rodless chamber.

[0028] The piston assembly 1 is provided with a control oil chamber 11, an overflow block 23, a valve core 28, and an oil unloading channel 15; wherein valves are provided between the control oil chamber 11 and the rod chamber and the rodless chamber. When the shock absorber is in the compression stroke, the oil pressure in the rodless chamber is greater than the opening threshold of the valve between the rodless chamber and the control oil chamber 11, and the oil can enter the control oil chamber 11 from the rodless chamber. When the shock absorber is in the rebound stroke, the oil pressure in the rod chamber is greater than the opening threshold of the valve between the rod chamber and the control oil chamber 11, and the oil can enter the control oil chamber 11 from the rod chamber.

[0029] The valve core 28 is set as a cylindrical structure, and a large diameter section 27 and a small diameter section 26 are sequentially arranged along its axial direction. The diameter of the large diameter section 27 is larger than the diameter of the small diameter section 26, and the large diameter section 27 and the small diameter section 26 constitute a stepped shaft structure, and a stepped surface is formed between the two.

[0030] The overflow block 23 is an annular structure with a hollow portion. The valve core 28 is axially displaceable in the hollow portion of the overflow block 23, and a first oil passage 25 is formed between the small diameter section 26 and the side wall of the hollow portion. A first overflow hole 13 communicating with both the first oil passage 25 and the control oil chamber 11 is provided on the side wall of the overflow block 23, and a second overflow hole 14 communicating with the oil unloading channel 15 is also provided on the side wall of the overflow block 23. The valve core 28 can be switched between a first position and a second position in the axial direction. In the first position, the large diameter section 27 of the valve core 28 separates the first oil passage 25 from the second overflow hole 14. In the second position, the first oil passage 25 is connected to the second overflow hole 14.

[0031] It should be noted that when the shock absorber is in a non-working state, the oil pressure in the rod chamber and the rodless chamber is in a balanced state, and the valve core 28 is kept in the first position under the magnetic field force generated by the solenoid, directly isolating the first oil passage 25 and the second overflow hole 14. When the shock absorber is in a compression stroke, the oil pressure in the rodless chamber increases, and the oil in the rodless chamber enters the control oil chamber 11 through the valve, and the oil pressure in the control oil chamber 11 increases, and enters the first oil passage 25 through the first overflow hole 13, and the oil pressure acts on the stepped surface formed by the large diameter section 27 and the small diameter section 26 of the valve core 28, thereby pushing the valve core 28 to overcome the magnetic field force and axially displace to the second position. At this time, the first oil passage 25 is connected with the second overflow hole 14, and the oil in the first oil passage 25 enters the oil unloading passage 15 through the second overflow hole 14, and enters the rod chamber through the oil unloading passage 15, thereby realizing the damping effect of the shock absorber. When the shock absorber is in the rebound stroke, the oil pressure in the rod chamber increases, and the oil in the rod chamber enters the control oil chamber 11 through the valve, the oil pressure in the control oil chamber 11 increases, and enters the first oil passage 25 through the first overflow hole 13, and the oil pressure acts on the stepped surface formed by the large diameter section 27 and the small diameter section 26 of the valve core 28, thereby pushing the valve core 28 to overcome the magnetic field force and axially displace to the second position. At this time, the first oil passage 25 is connected with the second overflow hole 14, and the oil in the first oil passage 25 enters the oil unloading passage 15 through the second overflow hole 14, and enters the rodless chamber through the oil unloading passage 15, thereby realizing the damping effect of the shock absorber.

[0032] Obviously, in this embodiment, the valve core 28 is set to a sliding form to form a sliding valve structure, and the on-off control of the oil circuit is achieved by cooperating with the overflow block 23. The sliding valve structure has good stability and can effectively avoid the problem of oil leakage.

[0033] In a further embodiment, the number of the second overflow holes 14 on the overflow block 23 can be multiple and evenly distributed along the circumference of the overflow block 23. In this embodiment, the damping force of the shock absorber can be adjusted by designing different numbers of the second overflow holes 14. Therefore, the shock absorber provided in this embodiment has a larger adjustment range of the damping force.

[0034] In a further embodiment, a first overflow channel 29 is provided in the piston assembly 1, and the first overflow channel 29 connects the rod chamber and the rodless chamber. When the shock absorber is in a compression stroke or a rebound stroke, the oil in the rod chamber and the rodless chamber can flow through the first overflow channel 29, thereby playing a role in lowering the damping force of the shock absorber. It should be noted that the aperture size of the first overflow channel 29 can be set according to the damping force requirement of the shock absorber.

[0035] In some embodiments, the overflow block 23 is configured as a cylindrical structure with a hollow portion, wherein the hollow portion includes a large diameter portion and a small diameter portion in sequence along the axial direction, a first oil passage 25 is formed between the side wall of the large diameter portion and the small diameter section 26 of the valve core 28, and the small diameter portion is sealed with the small diameter section 26 of the valve core 28. Specifically, a sealing ring may be sleeved on the outer periphery of the small diameter section 26 of the valve core 28, and a sealing ring is used to achieve a sealing match with the small diameter portion of the overflow block 23 to avoid oil leakage.

[0036] In a further embodiment, the piston assembly 1 is provided with a second overflow channel 19 connected to the small diameter portion and the rodless chamber, and the port of the second overflow channel 19 connected to the small diameter portion corresponds to the lower end of the valve core 28. In this way, when the shock absorber is in the compression stroke, the oil can enter the control oil chamber 11 and the second overflow channel 19 at the same time under the action of pressure. The oil entering the control oil chamber 11 enters the first oil channel 25 through the first overflow hole 13, and the oil pressure acts on the stepped surface formed by the large diameter section 27 and the small diameter section 26 of the valve core 28, thereby pushing the valve core 28 to overcome the magnetic field force and move to the second position. At the same time, the oil enters the second overflow channel 19, and the oil pressure acts on the end of the valve core 28, which can play a role in assisting the valve core 28. The aperture size of the second overflow channel 19 can be designed accordingly according to the different damping forces required by the shock absorber.

[0037] In a further embodiment, a first oil circuit, a second oil circuit 16, a third oil circuit 20 and a fourth oil circuit 21 are provided in the piston assembly 1; wherein one end of the first oil circuit and the second oil circuit 16 are communicated with the rod chamber, the other end of the first oil circuit is communicated with the control oil chamber 11, and the other end of the second oil circuit 16 is communicated with the second port of the oil unloading passage 15. One end of the third oil circuit 20 and the fourth oil circuit 21 are communicated with the rodless chamber, the other end of the third oil circuit 20 is communicated with the control oil chamber 11, and the other end of the fourth oil circuit 21 is communicated with the second port of the oil unloading passage 15. The second oil circuit 16 and the fourth oil circuit 21 may pass through the axis of the valve core 28.

[0038] The valves include a first one-way valve 12 and a third one-way valve 18, and the piston assembly 1 also includes a second one-way valve 17 and a fourth one-way valve 22. The first one-way valve 12, the second one-way valve 17, the third one-way valve 18 and the fourth one-way valve 22 are respectively arranged in a one-to-one correspondence with the first oil circuit, the second oil circuit 16, the third oil circuit 20 and the fourth oil circuit 21.

[0039] When the oil pressure in the rod chamber is greater than the oil pressure in the control oil chamber 11, and the oil pressure in the control oil chamber 11 is greater than the oil pressure in the rodless chamber, the first one-way valve 12 and the fourth one-way valve 22 are connected. When the oil pressure in the rodless chamber is greater than the oil pressure in the control oil chamber 11, and the oil pressure in the control oil chamber 11 is greater than the oil pressure in the rod chamber, the third one-way valve 18 and the second one-way valve 17 are connected.

[0040] With such arrangement, when the shock absorber is in the compression stroke, the oil in the rodless chamber passes through the third oil passage 20 and the third one-way valve 18 to enter the control oil chamber 11, and then flows through the first overflow hole 13 and the first oil passage 25 in sequence, and the oil pressure acts on the stepped surface formed by the large diameter section 27 and the small diameter section 26 of the valve core 28, thereby pushing the valve core 28 to overcome the magnetic field force and axially displace to the second position. At this time, the first oil passage 25 is connected with the second overflow hole 14, and the oil in the first oil passage 25 enters the oil unloading passage 15 through the second overflow hole 14, and then flows through the second one-way valve 17 and the second oil passage 16 in sequence after entering the oil unloading passage 15 to enter the rod chamber.

[0041] When the shock absorber is in the rebound stroke, the oil in the rod chamber passes through the first oil circuit and the first one-way valve 12 to enter the control oil chamber 11, and then flows through the first overflow hole 13 and the first oil channel 25 in sequence. The oil pressure acts on the stepped surface formed by the large diameter section 27 and the small diameter section 26 of the valve core 28, thereby pushing the valve core 28 to overcome the magnetic field force and axially displace to the second position. At this time, the first oil channel 25 is connected with the second overflow hole 14, and the oil in the first oil channel 25 enters the oil unloading channel 15 through the second overflow hole 14. After entering the oil unloading channel 15, it flows through the fourth one-way valve 22 and the fourth oil circuit 21 in sequence and enters the rod chamber.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0043] Reference numerals list

[0044] 1: Piston assembly; 11: Control oil chamber; 12: First one-way valve; 13: First overflow hole; 14: Second overflow hole; 15: Oil unloading channel; 16: Second oil circuit; 17: Second one-way valve; 18: Third one-way valve; 19: Second overflow channel; 20: Third oil circuit; 21: Fourth oil circuit; 22: Fourth one-way valve; 23: Overflow block; 25: First oil channel; 26: Small diameter section; 27: Large diameter section; 28: Valve core; 29: First overflow channel.

Claims

1. A shock absorber, comprising a cylinder and a piston assembly (1), wherein the piston assembly (1) divides the cylinder into a rod chamber and a rodless chamber, and the piston assembly (1) is provided with a control oil chamber (11), an overflow block (23), a valve core (28), and an oil unloading channel (15); wherein: Valves are provided between the control oil chamber (11) and the rod chamber and the rodless chamber; The valve core (28) is provided with a large diameter section (27) and a small diameter section (26) in sequence along its axial direction, and the diameter of the large diameter section (27) is larger than the diameter of the small diameter section (26); The overflow block (23) is an annular structure with a hollow portion, the valve core (28) is axially displaceably arranged in the hollow portion of the overflow block (23), and a first oil passage (25) is formed between the small diameter section (26) and the side wall of the hollow portion, a first overflow hole (13) communicating with both the first oil passage (25) and the control oil chamber (11) is arranged on the side wall of the overflow block (23), and a second overflow hole (14) communicating with the oil unloading passage (15) is also arranged on the side wall of the overflow block (23); wherein, The valve core (28) can slide and switch between a first position and a second position along the axial direction. When in the first position, the large diameter section (27) of the valve core (28) separates the first oil passage (25) and the second overflow hole (14). When in the second position, the first oil passage (25) is connected to the second overflow hole (14).

2. The shock absorber according to claim 1, wherein: The second overflow holes (14) are arranged in plurality and are evenly distributed along the circumference of the overflow block (23).

3. The shock absorber according to claim 1, wherein: A first overflow channel (29) is provided in the piston assembly (1), and the first overflow channel (29) connects the rod chamber and the rodless chamber.

4. The shock absorber according to claim 1, wherein: The hollow portion of the overflow block (23) comprises a large diameter portion and a small diameter portion, the first oil passage (25) is formed between the side wall of the large diameter portion and the small diameter section (26) of the valve core (28); the small diameter portion is in sealing cooperation with the small diameter section (26) of the valve core (28).

5. The shock absorber according to claim 4, wherein: The piston assembly (1) is provided with a second overflow channel (19) communicating with the small diameter portion and the rodless chamber, and a port of the second overflow channel (19) communicating with the small diameter portion corresponds to the lower end of the valve core (28).

6. The shock absorber according to any one of claims 1 to 5, wherein: The piston assembly (1) is provided with a first oil circuit, a second oil circuit (16), a third oil circuit (20) and a fourth oil circuit (21); wherein: One end of the first oil circuit and the second oil circuit (16) are connected to the rod chamber, the other end of the first oil circuit is connected to the control oil chamber (11), and the other end of the second oil circuit (16) is connected to the second port of the oil unloading channel (15); one end of the third oil circuit (20) and the fourth oil circuit (21) are connected to the rodless chamber, the other end of the third oil circuit (20) is connected to the control oil chamber (11), and the other end of the fourth oil circuit (21) is connected to the second port of the oil unloading channel (15).

7. The shock absorber according to claim 6, wherein: The valve comprises a first one-way valve (12) and a third one-way valve (18), and the piston assembly (1) further comprises a second one-way valve (17) and a fourth one-way valve (22), wherein the first one-way valve (12), the second one-way valve (17), the third one-way valve (18) and the fourth one-way valve (22) are respectively arranged in a one-to-one correspondence with the first oil circuit, the second oil circuit (16), the third oil circuit (20) and the fourth oil circuit (21); When the oil pressure in the rod chamber is greater than the oil pressure in the control oil chamber (11), and the oil pressure in the control oil chamber (11) is greater than the oil pressure in the rodless chamber, the first one-way valve (12) and the fourth one-way valve (22) are connected; when the oil pressure in the rodless chamber is greater than the oil pressure in the control oil chamber (11), and the oil pressure in the control oil chamber (11) is greater than the oil pressure in the rod chamber, the third one-way valve (18) and the second one-way valve (17) are connected.

8. The shock absorber according to claim 7, wherein: The second oil passage (16) and the fourth oil passage (21) pass through the axis of the valve core (28).

Images