Piston mechanism and hydraulic shock absorber

Abstract

The present application relates to the technical field of shock absorbers, and in particular to a piston mechanism and a hydraulic shock absorber. The piston mechanism includes a piston rod, a solenoid valve assembly, a spool valve, and a rebound valve system. The piston rod is inserted into the working cylinder of the hydraulic shock absorber. Both ends of the solenoid valve assembly are respectively connected to the piston rod and the rebound valve system. The rebound valve system divides the working cylinder into a rod chamber and a rodless chamber. The spool valve is located in the accommodation chamber formed by the rebound valve system and the solenoid valve assembly, and divides it into a first chamber and a second chamber. When the solenoid valve assembly is energized, the first valve port and the second valve port of the solenoid valve assembly are connected, so that the first chamber is connected to the rod chamber through the solenoid valve assembly. A second through hole for communicating the second chamber and the rod chamber is provided on the side wall of the second chamber, and the spool valve can block the second through hole. By adjusting the opening degree of the solenoid valve assembly, the pressure of the first chamber is adjusted to adjust the opening degree of the spool valve, thereby realizing the adjustment of the damping force generated when the oil passes through the rebound valve system.

Description

Technical Field

[0001] The present application relates to the technical field of shock absorbers, and in particular to a piston mechanism and a hydraulic shock absorber. Background Art

[0002] Hydraulic shock absorbers are commonly used in automobile suspension systems. When the shock absorber is working, the piston rod will reciprocate in the working cylinder of the shock absorber, and the oil in the oil storage cylinder will generate damping force through the valve system. The damping force of the conventional solenoid valve is fixed and cannot automatically control the size of the damping force of the shock absorber, so the electronically controlled shock absorber came into being.

[0003] Currently, the main electronically controlled shock absorbers are all external solenoid valve electronically controlled shock absorbers. The solenoid valve is placed on the outside of the shock absorber, and the damping force is controlled by controlling the size of the bypass oil channel. The diameter of the oil storage cylinder of the external solenoid valve shock absorber is designed to be large, which is not conducive to the layout of the chassis. At the same time, the layout of the external solenoid valve also increases the difficulty of spatial layout of the vehicle chassis suspension, and the external solenoid valve also increases the weight of the product, which invisibly increases the weight of the entire vehicle. Summary of the invention

[0004] The object of the present invention is to provide a piston mechanism and a hydraulic shock absorber, so as to place a solenoid valve in a working cylinder of the shock absorber and realize the adjustment of the damping force.

[0005] The present invention provides a piston mechanism, including a piston rod, a solenoid valve assembly, a sliding valve and a restoring valve system; the piston rod is used to be arranged in a working cylinder of a hydraulic shock absorber, and the solenoid valve assembly is installed at one end of the piston rod located in the working cylinder; the solenoid valve assembly is formed with a first valve port and a second valve port, and when the solenoid valve assembly is energized, the first valve port and the second valve port are connected; the restoring valve system is connected to one end of the solenoid valve assembly away from the piston rod, the restoring valve system divides the working cylinder into a rod chamber and a rodless chamber, and a accommodating chamber is formed between the restoring valve system and the solenoid valve assembly; the sliding valve is movably arranged in the accommodating chamber and is clearance-matched with the accommodating chamber, and the sliding valve divides the accommodating chamber into A first chamber and a second chamber; the first valve port is connected to the rod chamber, and the second valve port is connected to the first chamber; the sliding valve is formed with a first through hole to connect the first chamber and the second chamber, and the second chamber is connected to the rodless chamber through the recovery valve system; a second through hole is formed on the side wall of the second chamber to connect the second chamber and the rod chamber, the sliding valve has a first station located at the top and a second station located at the bottom, and when the sliding valve is located at the second station, the sliding valve can block the second through hole; the side wall of the sliding valve facing the second through hole is formed with an inclined wall surface, so that when the sliding valve in the second station blocks the second through hole, a smaller slit is opened in the second through hole.

[0006] Further, the solenoid valve assembly includes a valve body assembly, a moving iron core assembly, and a coil; the valve body assembly includes a first housing, a magnetic isolation ring, a second housing, and a pilot valve seat; one end of the first housing is connected to the piston rod, the other end of the first housing is connected to one end of the second housing through the magnetic isolation ring, and the other end of the second housing is connected to the restoring valve system; the pilot valve seat is hermetically connected to the second housing, a valve cavity is formed between the pilot valve seat and the first housing, and the accommodating chamber is formed between the pilot valve seat and the restoring valve system; the first housing forms the first valve port, and the pilot valve seat forms the second valve port; the moving iron core assembly is disposed in the valve cavity, and a first elastic member is disposed between the moving iron core assembly and the first housing, so that the moving iron core assembly blocks the second valve port; the coil is wound around the valve body assembly, and when the coil is charged, the first housing can generate a magnetic force to attract the moving iron core assembly away from the second valve port.

[0007] Further, the moving iron core assembly includes a moving iron core sleeve, an elastic member mounting seat, and a top cone; the moving iron core sleeve is located in the valve cavity, and the top cone is connected to one end of the moving iron core sleeve facing the pilot valve seat; a conical head is formed at one end of the top cone facing the pilot valve seat, the conical head can extend into the second valve port, and the side wall of the conical head can be hermetically abutted against the port of the second valve port; the elastic member mounting seat is disposed in the moving iron core sleeve, and both ends of the first elastic member are respectively abutted against the elastic member mounting seat and the top cone; a plug hole is formed at one end of the moving iron core sleeve facing the first housing, and a push rod is disposed on the first housing, and the push rod can extend into the moving iron core sleeve through the plug hole and abut against the elastic member mounting seat.

[0008] Further, the second valve port includes a first communicating portion and a second communicating portion that are communicated; the first communicating portion is located at one end close to the top cone, and the diameter of the first communicating portion is larger than the diameter of the second communicating portion; a conical head is formed at one end of the top cone facing the pilot valve seat, the conical head can extend into the first communicating portion, and the side wall of the conical head is hermetically abutted against the port of the first communicating portion.

[0009] Further, the diameter of the second communicating portion is 0.3 - 1.0 mm, and the diameter of the first through hole located on the spool valve is 0.5 - 2.0 mm.

[0010] Further, a predetermined gap is provided between the push rod and the plug hole, and a communication hole is formed in the top cone, so that the moving iron core sleeve is communicated with the valve cavity and the first valve port.

[0011] Further, a first mounting hole is formed in the first housing, and a first internal thread connecting portion is formed in the first mounting hole; one end of the ejector rod forms a first external thread connecting portion adapted to the first internal thread connecting portion, so that the ejector rod is screwed to the first housing; a first sealing groove is formed in the side wall of the ejector rod located in the first mounting hole, and a first sealing member is arranged in the first sealing groove, and the first sealing member is clamped between the ejector rod and the first mounting hole.

[0012] Further, a stop portion is formed on the inner side wall of the second housing, and the stop portion is located in the second chamber; the spool valve is located between the stop portion and the pilot valve seat, and a second elastic member is arranged between the pilot valve seat and the spool valve, so that the spool valve abuts against the stop portion; when the spool valve abuts against the stop portion, the spool valve can partially block the second through hole.

[0013] Further, the stop portion includes a snap ring; a mounting groove is formed in the side wall of the second chamber, the snap ring is embedded in the mounting groove, and the snap ring protrudes from the side wall of the second chamber.

[0014] Further, the solenoid valve assembly further includes an end cap; one end of the end cap is connected to the piston rod, and a second mounting hole is formed at the other end of the end cap; the first housing can be inserted into the mounting hole, and the end cap and the housing are fixed by a dowel pin; the piston rod is a hollow piston rod, and a hollow sleeve is formed at one end of the piston rod facing the solenoid valve assembly; a second internal thread connecting portion is formed on the inner wall of the hollow sleeve, and a second external thread connecting portion adapted to the second internal thread connecting portion is formed on the outer wall surface of the end cap, so that the end cap is screwed to the hollow sleeve.

[0015] Further, the end cap is formed with a first passage and a first annular groove; the first annular groove is located on the end face of the end cap facing the hollow sleeve, one end of the first passage is communicated with the first annular groove, and the other end of the first passage is communicated with the first valve port; a second passage is formed on the hollow sleeve, one end of the second passage is communicated with the rod chamber, and the other end of the second passage is communicated with the first annular groove.

[0016] Further, a second annular groove and a third annular groove are also formed on one end face of the end cap facing the hollow sleeve; the first annular groove is located between the second annular groove and the third annular groove, and second seals are respectively arranged in the second annular groove and the third annular groove, and the second seals are clamped between the end cap and the hollow sleeve; a second seal groove is formed at the end face where the first housing is in contact with the end cap, and the second seal groove communicates with the first valve port and the first passage; a third seal is arranged in the second seal groove, and the third seal is clamped between the first housing and the end cap.

[0017] The present invention also provides a hydraulic shock absorber, including the piston mechanism described in any one of the above.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] The piston mechanism provided by the present invention includes a piston rod, an electromagnetic valve assembly, a spool valve, and a rebound valve system. One end of the piston rod is inserted into the working cylinder of the hydraulic shock absorber, and the piston rod can reciprocate in the working cylinder along the axial direction of the piston rod, i.e., the vertical direction. The electromagnetic valve assembly is connected to one end of the piston rod located in the working cylinder, the rebound valve system is connected to the lower end of the electromagnetic valve assembly, and the rebound valve system divides the working cylinder into a rod chamber and a rodless chamber. An accommodation chamber is formed between the rebound valve system and the electromagnetic valve assembly, the spool valve is located in the accommodation chamber, divides the accommodation chamber into a first chamber and a second chamber, and the spool valve can move up and down between a first position and a second position in the accommodation chamber. The electromagnetic valve assembly is formed with a first valve port and a second valve port. When the electromagnetic valve assembly is energized, the electromagnetic valve assembly is opened, the first valve port and the second valve port are communicated, the electromagnetic valve assembly is communicated with the rod chamber through the first valve port, and the electromagnetic valve assembly is communicated with the first chamber through the second valve port; a first through hole is formed in the spool valve, so that the first chamber and the second chamber can be communicated through the first through hole. A second through hole is formed in the side wall of the second chamber for communicating the second chamber and the rod chamber; when the spool valve is located at the lowest second position, the side wall of the spool valve can block the second through hole; when the second chamber and the rod chamber conduct oil fluid circulation, it is necessary to push the spool valve upward, that is, to open the spool valve.

[0020] During the process of oil flow between the second chamber and the rod chamber, the oil acts on the spool valve and needs to overcome the pressure in the first chamber to push the spool valve upward. Therefore, by changing the pressure in the first chamber, the opening degree of the spool valve can be adjusted. The pressure in the first chamber depends on the opening degree of the solenoid valve assembly, that is, the larger the energizing current of the solenoid valve assembly, the larger the opening degree of the solenoid valve assembly, the smaller the pressure in the first chamber, the easier it is to open the spool valve, the smaller the pressure in the second chamber, the larger the opening degree of the valve orifice of the restoring valve system, and the smaller the damping force of the oil passing through the restoring valve system, and vice versa. When the solenoid valve assembly is de-energized, the solenoid valve assembly is closed, and the oil inside the first chamber cannot be discharged into the rod chamber through the solenoid valve assembly when the first chamber is compressed. The pressure in the first chamber is the largest, and it is the most difficult to open the spool valve. At this time, the damping force is the largest, thus realizing the adjustment of the damping force of the hydraulic shock absorber.

[0021] The present invention also provides a hydraulic shock absorber, including the piston mechanism described above, so the hydraulic shock absorber also has the beneficial effects of the piston mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a schematic structural diagram of the hydraulic shock absorber provided by the embodiment of the present invention;

[0024] Figure 2 It is a schematic structural diagram of the piston mechanism provided by the embodiment of the present invention;

[0025] Figure 3 It is a schematic structural diagram of the solenoid valve assembly provided by the embodiment of the present invention;

[0026] Figure 4 It is a schematic structural diagram of the moving iron core assembly provided by the embodiment of the present invention.

[0027] Reference numerals:

[0028] 1 - Working cylinder, 11 - Rod chamber, 12 - Rodless chamber, 2 - Piston rod, 21 - Hollow sleeve, 22 - Second passage, 3 - Solenoid valve assembly, 31 - First valve port, 32 - Second valve port, 33 - Coil, 34 - First housing, 35 - Magnetic isolation ring, 36 - Second housing, 37 - Pilot valve seat, 38 - Moving iron core sleeve, 39 - Elastic part mounting seat, 310 - Top cone, 311 - Cone head, 312 - Push rod, 313 - First communication part, 314 - Second communication part, 315 - Insertion hole, 316 - Communication hole, 317 - First seal, 318 - End cover, 319 - Cotter pin, 320 - First passage, 321 - First annular groove, 322 - Second seal, 333 - Third seal, 4 - Slide valve, 41 - First through hole, 5 - Restoration valve system, 6 - First chamber, 7 - Second chamber, 71 - Second through hole, 72 - Circlip, 8 - First elastic part, 9 - Second elastic part. Detailed implementation mode

[0029] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments.

[0030] Generally, the components of the embodiments of the present invention described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention.

[0031] All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The following refers to Figures 1 to 4 Describe the piston mechanism and hydraulic shock absorber according to some embodiments of the present application.

[0035] The present application provides a piston mechanism, as Figures 1 to 3 shown, for a hydraulic shock absorber; the piston mechanism includes a piston rod 2, a solenoid valve assembly 3, a spool valve 4, and a rebound valve system 5.

[0036] One end of the piston rod 2 is inserted into the working cylinder 1 of the hydraulic shock absorber. The piston rod 2 is located at the upper end of the working cylinder 1, and the piston rod 2 can reciprocate in the working cylinder 1 along the axial direction of the piston rod 2, that is, the vertical direction.

[0037] The solenoid valve assembly 3 is arranged in the working cylinder 1, and the upper end of the solenoid valve assembly 3 is connected to one end of the piston rod 2 located in the working cylinder 1. The rebound valve system 5 is located at the lower end of the solenoid valve assembly 3, and the rebound valve system 5 is connected to the lower end of the solenoid valve assembly 3; the rebound valve system 5 is adapted to the working cylinder 1, and the rebound valve system 5 can be in clearance fit with the inner wall of the working cylinder 1, so that the rebound valve system 5 and the solenoid valve can reciprocate in the working cylinder 1 along the vertical direction with the piston rod 2. At the same time, the working cylinder 1 is divided into two relatively independent chambers by the rebound valve system 5, that is, the rod chamber 11 located above the rebound valve system 5 and the rodless chamber 12 located below the rebound valve system 5.

[0038] The connection between the rebound valve system 5 and the solenoid valve assembly 3 also forms an accommodation chamber between the rebound valve system 5 and the solenoid valve assembly 3. The spool valve 4 is arranged in the accommodation chamber. The accommodation chamber is divided into two relatively independent chambers by the spool valve 4, that is, the first chamber 6 located above the spool valve 4 and the second chamber 7 located below the spool valve 4; the spool valve 4 is in clearance fit with the inner wall of the accommodation chamber, so that the spool valve 4 can move up and down in the accommodation chamber, and the spool valve 4 has a first working position located above and a second working position located below. The spool valve 4 can move up and down between the first working position and the second working position, so that the volumes of the first chamber 6 and the second chamber 7 change.

[0039] As Figure 2 and Figure 3As shown, the solenoid valve assembly 3 is formed with a first valve port 31 and a second valve port 32. When the solenoid valve assembly 3 is energized, the solenoid valve assembly 3 opens, and the first valve port 31 and the second valve port 32 are connected. At the same time, by adjusting the magnitude of the energizing current of the solenoid valve assembly 3, the opening degree of the solenoid valve assembly 3 can be adjusted, and thus the flux of the solenoid valve assembly 3 can be adjusted. The solenoid valve assembly 3 is connected to the rod chamber 11 of the working cylinder 1 through the first valve port 31, and the solenoid valve assembly 3 is connected to the first chamber 6 through the second valve port 32. Therefore, when the solenoid valve assembly 3 opens, the first chamber 6 is connected to the rod chamber 11, and oil can flow between the first chamber 6 and the rod chamber 11. And by adjusting the magnitude of the energizing current of the solenoid valve, the opening degree of the solenoid valve is adjusted, and thus the flow rate of the oil between the first chamber 6 and the rod chamber 11 is adjusted. A first through hole 41 is formed in the spool valve 4, so that the first chamber 6 and the second chamber 7 can be connected through the first through hole 41, and oil can flow between the first chamber 6 and the second chamber 7. In this embodiment, preferably, the through hole of the first through hole 41 is 0.5 mm - 2.0 mm.

[0040] A second through hole 71 is formed in the side wall of the second chamber 7, and the second chamber 7 can be connected to the rod chamber 11 through the second through hole 71; when the spool valve 4 is in the second working position at the lowest position, the side wall of the spool valve 4 can block the second through hole 71; when oil flows between the second chamber 7 and the rod chamber 11, the spool valve 4 needs to be pushed upward, that is, the spool valve 4 is opened, and the second through hole 71 is opened, and oil can flow between the rod chamber 11 and the second chamber 7 through the second through hole 71. In this embodiment, preferably, the side wall of the spool valve 4 facing the second through hole 71 forms an inclined wall surface, so that when the spool valve 4 in the second working position blocks the second through hole 71, the second through hole 71 is opened with a small gap. When the oil in the rod chamber 11 flows through the second chamber 7 to the rodless chamber 12, the oil in the rod chamber 11 can act on the inclined wall surface of the spool valve 4 to push the spool valve 4 upward and open the spool valve 4.

[0041] In this embodiment, preferably, as Figure 3 shown, a second elastic member 9 is provided between the spool valve 4 and the solenoid valve assembly 3, and the elastic force of the second elastic member 9 can push the spool valve 4 downward to return to the second working position.

[0042] During the rebound stroke of the shock absorber, the piston rod 2 drives the rebound valve system 5 to move upward. The volume of the rod chamber 11 is compressed, and the hydraulic fluid in the rod chamber 11 will push the spool valve 4 upward to open the spool valve 4 and enter the second chamber 7. Then, the hydraulic fluid continues to open the rebound valve system 5 to enter the rodless chamber 12 to generate a rebound damping force. Similarly, during the compression stroke of the shock absorber, the piston rod 2 drives the rebound valve system 5 to move downward. The volume of the rodless chamber 12 is compressed, and the hydraulic fluid in the rodless chamber 12 opens the rebound valve system 5 to pass through the second chamber 7 and enter the rod chamber 11 to generate a compression damping force.

[0043] During the process of hydraulic fluid flowing between the second chamber 7 and the rod chamber 11, the hydraulic fluid acts on the spool valve 4 and needs to overcome the elastic force exerted by the second elastic member 9 on the spool valve 4 and the pressure in the first chamber 6 to be able to push the spool valve 4 upward. Thus, by changing the pressure in the first chamber 6, the opening degree of the spool valve 4 can be adjusted. The pressure in the first chamber 6 depends on the opening degree of the solenoid valve assembly 3, that is, the larger the energizing current of the solenoid valve assembly 3, the larger the opening degree of the solenoid valve assembly 3, the smaller the pressure in the first chamber 6, the easier it is to open the spool valve 4, the smaller the pressure in the second chamber 7, the larger the opening degree of the valve port of the rebound valve system 5, and the smaller the damping force of the hydraulic fluid passing through the rebound valve system 5, and vice versa. When the solenoid valve assembly 3 is de-energized, the solenoid valve assembly 3 is closed, and the hydraulic fluid inside the first chamber 6 cannot be discharged into the rod chamber 11 through the solenoid valve assembly 3 when the first chamber 6 is compressed. The pressure in the first chamber 6 is the largest, and it is the most difficult to open the spool valve 4. At this time, the damping force is the largest. Thus, the adjustment of the damping force is realized. During use, different currents can be input to the solenoid valve assembly 3 according to different road conditions to improve the riding comfort and driving safety of the vehicle. At the same time, by using an internal solenoid valve, the external dimensions of the shock absorber can be designed to be smaller, which is more conducive to the layout of the vehicle chassis space, reduces weight, and is convenient for production and processing.

[0044] In an embodiment of the present application, preferably, as Figure 2 and Figure 3As shown, the solenoid valve assembly 3 includes a valve body assembly, a moving iron core assembly, and a coil 33. The valve body assembly includes a first housing 34, a magnetic isolation ring 35, a second housing 36, and a pilot valve seat 37. The upper end of the first housing 34 is connected to the piston rod 2, and the lower end of the first housing 34 is connected to the upper end of the second housing 36 through the magnetic isolation ring 35. The upper end of the first housing 34 is a closed end, and the lower end of the second housing 36 is an open end. The pilot valve seat 37 is disposed inside the second housing 36 and is sealingly connected to the second housing 36. Thus, a valve cavity of the solenoid valve assembly 3 is formed by the first housing 34, the magnetic isolation ring 35, the second housing 36, and the pilot valve seat 37. A first valve port 31 is located on the first housing 34, and the valve cavity communicates with the rod chamber 11 through the first valve port 31. A second valve port 32 is located on the pilot valve seat 37. The second housing 36 extends downward by a predetermined length, and the lower end of the second housing 36 is connected to the restoring valve system 5 to form the above-mentioned accommodation chamber between the second housing 36, the pilot valve seat 37, and the restoring valve system 5. The spool valve 4 is installed in the accommodation chamber and is in clearance fit with the second housing 36, so that a first chamber 6 is formed between the spool valve 4 and the pilot valve seat 37, and a second chamber 7 is formed between the spool valve 4 and the restoring valve system 5. A second elastic member 9 is located in the first chamber 6, and both ends of the second elastic member 9 abut against the pilot valve seat 37 and the spool valve 4 respectively. Preferably, as Figure 3 shown, a stop portion is provided on the inner wall of the second housing 36 where the second chamber 7 is located. When the spool valve 4 moves to the second working position, the lower end surface of the spool valve 4 will abut against the stop portion, thereby limiting the spool valve 4 through the stop portion. Preferably, the stop portion can be a snap ring 72. An installation groove is formed on the side wall of the second chamber 7, and the snap ring 72 is embedded in the installation groove and protrudes from the side wall of the second chamber 7 to form a stop portion for limiting the spool valve 4.

[0045] The coil 33 is disposed around the outside of the valve body assembly and is located on the side close to the first housing 34. When an electric current is passed through the coil 33, the first housing 34 will generate a magnetic force, and by adjusting the magnitude of the electric current passed through, the magnitude of the magnetic force generated by the first housing 34 can be adjusted.

[0046] The moving iron core assembly is arranged in the valve cavity, that is, the moving iron core assembly is located between the first housing 34 and the pilot valve seat 37, and the moving iron core can move between the first housing 34 and the pilot valve seat 37. A first elastic member 8 is arranged between the moving iron core assembly and the first housing 34. The elastic force of the first elastic member 8 can make the moving iron core assembly move to a position where it abuts against the pilot valve seat 37, so as to block the second valve port 32 of the pilot valve seat 37 through the moving iron core assembly; when an electric current is passed through the coil 33, the magnetic force generated by the first housing 34 will attract the moving iron core to move upward close to the first housing 34 to open the second valve port 32, the solenoid valve assembly 3 is opened, the first valve port 31 is communicated with the second valve port 32, and the first chamber 6 is communicated with the rod chamber 11 through the solenoid valve assembly 3.

[0047] In this embodiment, preferably, as Figure 3 and 4 shown, the moving iron core assembly includes a moving iron core sleeve 38 and a top cone 310; the moving iron core sleeve 38 is arranged in the valve cavity, the lower end of the moving iron core sleeve 38 is connected to the top cone 310, a cone head 311 is formed at one end of the top cone 310 facing the pilot valve seat 37, and the cone head 311 and the second valve port 32 are located on the same axis; when the moving iron core assembly abuts against the pilot valve seat 37, the head end of the cone head 311 can be inserted into the second valve port 32, and the side wall of the cone head 311 is closely abutted against the port of the second valve port 32, so as to seal and block the second valve port 32 through the cone head 311. When the coil 33 is charged, the moving iron core assembly moves upward, and the cone head 311 withdraws from the second valve port 32 by a certain distance, so that a certain annular gap is formed between the outer wall of the cone head 311 and the second valve port 32, the second valve port 32 is opened, and the first chamber 6 can be communicated with the valve cavity through the second valve port 32; the greater the current passed through the coil 33, the more the cone head 311 withdraws from the second valve port 32, the larger the annular gap between the cone head 311 and the second valve port 32, and the greater the opening degree of the second valve port 32, that is, the opening degree of the solenoid valve assembly 3.

[0048] In this embodiment, preferably, as Figure 3 shown, the second valve port 32 includes a first communicating portion 313 and a second communicating portion 314 which are communicated with each other. The first communicating portion 313 is located on the side of the pilot valve seat 37 facing the top cone 310, the second communicating portion 314 is located on the side facing the first chamber 6, and the second communicating portion 314 has a smaller diameter. Preferably, the diameter of the second communicating portion 314 is 0.3 mm - 1.0 mm. The first communicating portion 313 has a larger diameter to facilitate the assembly of the cone head 311 and the first communicating portion 313. The cone head 311 can extend into the first communicating portion 313 so as to block the first communicating portion 313 through the cone head 311.

[0049] Regarding the installation of the first elastic member 8 between the moving iron core assembly and the first housing 34, preferably, asFigure 3 and Figure 4 As shown in Figure 3 and Figure 4 , a plug hole 315 is formed at the upper end of the moving iron core sleeve 38. A push rod 312 is provided on the first housing 34. The upper end of the push rod 312 is connected to the first housing 34. The lower end of the push rod 312 extends into the moving iron core sleeve 38 through the plug hole 315. The moving iron core assembly further includes an elastic member mounting seat 39. The elastic member mounting seat 39 can be abutted and connected to the lower end of the push rod 312. The first elastic member 8 is located between the elastic mounting seat and the pilot valve seat 37. The upper end of the first elastic member 8 abuts against the elastic member mounting seat 39, and the lower end of the first elastic member 8 abuts against the top cone 310. Thus, the first elastic member 8 can provide a driving force to the moving iron core assembly, so that the moving iron core assembly abuts against the pilot valve seat 37, and the conical head 311 of the top cone 310 plugs the second valve port 32.

[0050] In this embodiment, preferably, as Figure 3 described, regarding the connection between the push rod 312 and the first housing 34, a first mounting hole is formed on the upper end surface of the first housing 34. A first internal thread connecting portion is formed on the inner wall surface of the upper end of the first mounting hole. A first external thread connecting portion is formed at the upper end of the push rod 312. The first external thread connecting portion is adapted to the first internal thread connecting portion, so that the upper end of the push rod 312 is screwed onto the first housing 34. A first sealing groove is formed on the side wall of the push rod 312 located in the first mounting hole. A first sealing member 317 is arranged in the first sealing groove. The first sealing member 317 can be clamped between the push rod 312 and the first mounting block, so that the push rod 312 is hermetically connected to the first housing 34.

[0051] In this embodiment, preferably, the moving iron core sleeve 38 is in clearance fit with the inner wall of the valve cavity, so that the moving iron core can move up and down in the valve cavity, and at the same time, it can play a guiding role for the moving iron core. The diameter of the plug hole 315 at the upper end of the moving iron core sleeve 38 is larger than the outer diameter of the push rod 312, so that a predetermined gap is formed between the plug interface and the push rod 312. The oil in the working cylinder 1 can enter the moving iron core sleeve 38 through the gap between the plug interface and the push rod 312 after passing through the first valve port 31 and entering the valve cavity. A communication hole 316 is formed on the top cone 310 for communicating the moving iron core sleeve 38 and the valve cavity, so that the valve cavity between the top cone 310 and the pilot valve seat 37 can be communicated with the moving iron core sleeve 38 through the communication hole 316.

[0052] In an embodiment of the present application, preferably, as Figure 3As shown, the solenoid valve assembly 3 further includes an end cap 318. A second mounting hole is formed in the lower end face of the end cap 318, and the second mounting hole is adapted to the first housing 34, such that the first housing 34 can be assembled into the second mounting hole. A dowel pin 319 is arranged in the second mounting hole, and a pin hole is correspondingly formed in the first housing 34. The dowel pin 319 can be inserted into the first housing 34 through the pin hole, thereby positioning and connecting the first housing 34 and the end cap 318 through the dowel pin 319.

[0053] Preferably, an installation annular groove is formed between the end cap 318 and the second housing 36, and the coil 33 is fixed in the installation annular groove.

[0054] In an embodiment of the present application, preferably, the piston rod 2 is a hollow piston rod 2, and a hollow sleeve 21 is formed at one end of the piston rod 2 located in the working cylinder 1, i.e., at the lower end of the piston rod 2. The solenoid valve assembly 3 is installed in the hollow sleeve 21.

[0055] Preferably, a second internal thread connection portion is formed on the upper end side wall of the hollow sleeve 21, and a second external thread connection portion is formed on the outer wall of the end cap 318. The second external thread connection portion is adapted to the second internal thread connection portion, such that the end cap 318 can be screwed to the hollow sleeve 21, thereby installing the solenoid valve assembly 3 in the hollow sleeve 21, and the upper end of the solenoid valve assembly 3 abuts against the top end of the hollow sleeve 21. A second annular groove and a third annular groove are formed on the upper end face of the end cap 318, and second sealing members 322 are respectively arranged in the second annular groove and the third annular groove. The second sealing members 322 can be clamped between the end cap 318 and the hollow sleeve 21 to seal-connect the end cap 318 and the hollow sleeve 21. The lower end of the hollow sleeve 21 extends to the second housing 36 of the solenoid valve assembly 3, and a sealing device, such as a sealing ring or a sealing gasket, etc., is arranged between the second housing 36 and the inner wall surface of the hollow sleeve 21, so that the solenoid valve assembly 3 is hermetically assembled in the hollow sleeve 21, and the hydraulic oil in the working cylinder 1 will not enter between the hollow sleeve 21 and the solenoid valve assembly 3, so as to prevent the coil 33 from being soaked in the hydraulic oil, and the lead-out end of the coil 33 can extend out of the piston rod 2 through the hollow sleeve 21.

[0056] In an embodiment of the present application, preferably, as Figure 2 and Figure 3As shown, a first duct 320 and a first annular groove 321 are formed on the end cap 318. The first annular groove 321 is located on the upper end face of the end cap 318. The first duct 320 is located on the side of the end cap 318 facing the first housing 34. One end of the first duct 320 communicates with a first valve port 31 formed on the first housing 34, and the other end of the first duct 320 communicates with the first annular groove 321. A second sealing groove is formed at one end of the first valve port 31 facing the first duct 320. A third seal 333 is disposed in the second sealing groove. The third seal 333 can be clamped between the first housing 34 and the end cap 318, so as to seal the communication between the first duct 320 and the first valve port 31 through the third seal 333.

[0057] Preferably, a second duct 22 is formed on the hollow sleeve 21. One end of the second duct 22 communicates with the rod chamber 11, and the other end of the second duct 22 communicates with the first annular groove 321. By providing the first annular groove 321, when the end cap 318 is screwed to the hollow sleeve 21, no matter what position it is screwed to, the second duct 22 can always communicate with the first duct 320 through the first annular groove 321. Preferably, the first annular groove 321 is located between a second annular groove and a third annular groove, so as to seal the communication between the second duct 22 and the first annular groove 321 through the second seals 322 in the second annular groove and the third annular groove.

[0058] The present application also provides a hydraulic shock absorber, including the piston mechanism of any of the above embodiments.

[0059] In this embodiment, the hydraulic shock absorber includes a piston mechanism. Therefore, the hydraulic shock absorber has all the beneficial effects of the piston mechanism, which will not be elaborated herein one by one.

[0060] 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 them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A piston mechanism, characterized in that, it includes a piston rod, a solenoid valve assembly, a spool valve and a return valve system; The piston rod is used to be arranged in the working cylinder of a hydraulic shock absorber, and the solenoid valve assembly is installed at one end of the piston rod located in the working cylinder; the solenoid valve assembly is formed with a first valve port and a second valve port, and when the solenoid valve assembly is energized, the first valve port and the second valve port are communicated with each other; The return valve system is connected to the end of the solenoid valve assembly away from the piston rod. The return valve system divides the working cylinder into a rod chamber and a rodless chamber, and an accommodation chamber is formed between the return valve system and the solenoid valve assembly; The spool valve is movably arranged in the accommodation chamber and is in clearance fit with the accommodation chamber. The spool valve divides the accommodation chamber into a first chamber and a second chamber; The first valve port is communicated with the rod chamber, and the second valve port is communicated with the first chamber; the spool valve is formed with a first through hole to communicate the first chamber and the second chamber, and the second chamber is communicated with the rodless chamber through the return valve system; The side wall of the second chamber is formed with a second through hole to communicate the second chamber and the rod chamber. The spool valve has a first working position above and a second working position below. When the spool valve is in the second working position, the spool valve can block the second through hole; The side wall of the spool valve facing the second through hole is formed with an inclined wall surface, so that when the spool valve in the second working position blocks the second through hole, the second through hole is opened with a smaller slit.

2. The piston mechanism according to claim 1, characterized in that, the solenoid valve assembly includes a valve body assembly, a moving iron core assembly and a coil; The valve body assembly includes a first housing, a magnetic isolation ring, a second housing and a pilot valve seat; One end of the first housing is connected to the piston rod, and the other end of the first housing is connected to one end of the second housing through the magnetic isolation ring, and the other end of the second housing is connected to the return valve system; The pilot valve seat is hermetically connected to the second housing. A valve chamber is formed between the pilot valve seat and the first housing, and the accommodation chamber is formed between the pilot valve seat and the return valve system; The first housing is formed with the first valve port, and the pilot valve seat is formed with the second valve port; The moving iron core assembly is arranged in the valve chamber, and a first elastic member is arranged between the moving iron core assembly and the first housing, so that the moving iron core assembly blocks the second valve port; The coil is wound around the valve body assembly. When the coil is charged, the first housing can generate a magnetic force to attract the moving iron core assembly away from the second valve port.

3. The piston mechanism according to claim 2, characterized in that, the moving iron core assembly includes a moving iron core sleeve, an elastic member mounting seat and a top cone; The moving iron core sleeve is located in the valve chamber, and the top cone is connected to one end of the moving iron core sleeve facing the pilot valve seat; One end of the top cone facing the pilot valve seat is formed with a conical head, which can extend into the second valve port, and the side wall of the conical head can be in sealing abutment with the port of the second valve port; The elastic member mounting seat is arranged inside the moving iron core sleeve, and two ends of the first elastic member are respectively abutted against the elastic member mounting seat and the top cone; One end of the moving iron core sleeve facing the first housing is formed with a socket hole, and a push rod is arranged on the first housing. The push rod can extend into the moving iron core sleeve through the socket hole and abut against the elastic member mounting seat.

4. The piston mechanism according to claim 3, characterized in that the second valve port includes a first communication part and a second communication part which are communicated with each other; the first communication part is located at one end close to the top cone, and the diameter of the first communication part is larger than that of the second communication part; One end of the top cone facing the pilot valve seat is formed with a conical head, which can extend into the first communication part, and the side wall of the conical head is in sealing abutment with the port of the first communication part.

5. The piston mechanism according to claim 4, characterized in that the diameter of the second communication part is 0.3 - 1.0 mm, and the diameter of the first through hole located on the spool valve is 0.5 - 2.0 mm.

6. The piston mechanism according to claim 3, characterized in that a predetermined gap exists between the push rod and the socket hole, and the top cone is formed with a communication hole, so that the moving iron core sleeve is communicated with the valve cavity and the first valve port.

7. The piston mechanism according to claim 3, characterized in that the first housing is provided with a first mounting hole, and the first mounting hole is formed with a first internal thread connecting part; one end of the push rod is formed with a first external thread connecting part adapted to the first internal thread connecting part, so that the push rod is screwed with the first housing; a first sealing groove is formed on the side wall of the push rod located in the first mounting hole, and a first sealing member is arranged in the first sealing groove. The first sealing member is clamped between the push rod and the first mounting hole.

8. The piston mechanism according to claim 2, characterized in that a stop portion is formed on the inner side wall of the second housing, and the stop portion is located in the second chamber; the spool valve is located between the stop portion and the pilot valve seat, and a second elastic member is arranged between the pilot valve seat and the spool valve, so that the spool valve abuts against the stop portion; when the spool valve abuts against the stop portion, the spool valve can partially block the second through hole.

9. The piston mechanism according to claim 8, characterized in that the stop portion includes a snap ring; a mounting groove is formed on the side wall of the second chamber, the snap ring is embedded in the mounting groove, and the snap ring protrudes from the side wall of the second chamber.

10. The piston mechanism according to claim 2, characterized in that the solenoid valve assembly further includes an end cover; One end of the end cap is connected to the piston rod, and a second mounting hole is formed at the other end of the end cap; the first housing can be inserted into the second mounting hole, and the end cap and the housing are fixed by a dowel pin; The piston rod is a hollow piston rod, and a hollow sleeve is formed at one end of the piston rod facing the solenoid valve assembly; A second internal thread connecting portion is formed on the inner wall of the hollow sleeve, and a second external thread connecting portion adapted to the second internal thread connecting portion is formed on the outer wall surface of the end cap, so that the end cap is screwed to the hollow sleeve.

11. The piston mechanism according to claim 10, characterized in that, The end cap is formed with a first hole and a first annular groove; The first annular groove is located on the end face of the end cap facing the hollow sleeve, one end of the first hole is communicated with the first annular groove, and the other end of the first hole is communicated with the first valve port; A second hole is formed on the hollow sleeve, one end of the second hole is communicated with the rod chamber, and the other end of the second hole is communicated with the first annular groove.

12. The piston mechanism according to claim 11, characterized in that, A second annular groove and a third annular groove are further formed on the end face of the end cap facing the hollow sleeve; The first annular groove is located between the second annular groove and the third annular groove, and second seals are respectively arranged in the second annular groove and the third annular groove, and the second seals are clamped between the end cap and the hollow sleeve; A second seal groove is formed at the end face where the first housing is attached to the end cap, and the second seal groove is communicated with the first valve port and the first hole; A third seal is arranged in the second seal groove, and the third seal is clamped between the first housing and the end cap.

13. A hydraulic shock absorber, characterized in that, It includes the piston mechanism according to any one of claims 1 to 12.

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