Piston valve of shock absorber

Abstract

The piston valve of the shock absorber comprises a piston shell, a main channel is formed by a gap between a magnetic core and the inner wall of the piston shell, and main through holes are formed in a first piston pressing plate and a second piston pressing plate; a secondary channel is arranged in the magnetic core, and the first piston pressing plate and the second piston pressing plate are respectively provided with an upper secondary through hole and a lower secondary through hole; the valve assembly is arranged above the first piston pressing plate, the valve assembly is used for shielding the previous through hole, and the valve assembly is of a normally-closed structure capable of opening the previous through hole under the action of magnetorheological fluid pressure; the sealing assembly comprises an upper sealing piece and a lower sealing piece, and the first piston pressing plate is in sealing connection with the upper portion of the magnetic core through the upper sealing piece; the second piston pressing plate is in sealing connection with the lower portion of the magnetic core through a lower sealing piece. The piston valve solves the problem that a leakage channel possibly exists between a main channel and a secondary channel of a piston valve in an existing magneto-rheological shock absorber, and consequently the shock absorber cannot achieve the asymmetric controllable damping characteristic.

Description

Technical Field

[0001] The utility model relates to the technical field of shock absorbers, in particular to a piston valve of a shock absorber. Background Art

[0002] The magnetorheological damper is a new type of actuator with adjustable damping force. Its working fluid is a magnetorheological fluid. The relative motion of the piston and cylinder compresses the fluid, forcing it through the damping channel on the piston, thereby generating shear force. Furthermore, the fluid's rheological properties change under the influence of a magnetic field. Under the influence of an external magnetic field, it can reversibly transform between a Newtonian fluid and a Bingham fluid within milliseconds. Consequently, the magnetorheological damper offers fast response speeds and a wide range of damping force adjustment. The piston valve in the magnetorheological shock absorber in the prior art fixes the magnetic core in the piston housing through the upper and lower pressure plates of the piston, and a main channel is formed between the magnetic core and the piston housing. In order to reduce the damping force value, in addition to the main channel, a secondary channel is generally provided inside the magnetic core. The magnetorheological fluid can flow through both the main channel and the secondary channel. The piston valve in the magnetorheological shock absorber in the prior art does not have an asymmetric controllable damping characteristic. Under the same conditions, the damping force of the piston valve during the restoring motion and the compression motion remains basically the same. If an asymmetric controllable damping characteristic is to be achieved, a normally closed valve assembly is generally required on the secondary channel. When the magnetorheological fluid enters the secondary channel, it may flow into the main channel along the gap between the first piston pressure plate and the magnetic core, or along the gap between the second piston pressure plate and the magnetic core, so that the magnetorheological fluid cannot open the valve assembly, resulting in the shock absorber being unable to achieve an asymmetric controllable damping characteristic. Utility Model Content

[0003] The purpose of the utility model is to provide a piston valve for a shock absorber, aiming to solve the problem that a leakage channel may exist between the main channel and the secondary channel of the piston valve in the existing magnetorheological shock absorber, so that the magnetorheological fluid cannot open the valve assembly of the secondary channel, resulting in the shock absorber being unable to achieve asymmetric controllable damping characteristics.

[0004] In order to achieve the above-mentioned purpose, the utility model discloses a piston valve of a shock absorber, comprising a piston housing: the piston housing is annular; a magnetic core: the magnetic core is fixedly installed in the piston housing through a first piston pressure plate and a second piston pressure plate, the gap between the magnetic core and the inner wall of the piston housing forms a main channel, and the first piston pressure plate and the second piston pressure plate are both provided with a main through hole for magnetorheological fluid to pass through; a secondary channel is provided in the magnetic core, the first piston pressure plate and the second piston pressure plate are respectively provided with an upper through hole and a lower through hole, and the secondary channel is connected to the upper through hole and the lower through hole respectively; a valve assembly: the valve assembly is arranged above the first piston pressure plate, the valve assembly is used to cover the upper through hole, and the valve assembly is a normally closed structure that can open the upper through hole under the action of magnetorheological fluid pressure; a sealing assembly: the sealing assembly includes an upper seal and a lower seal, the first piston pressure plate and the upper part of the magnetic core are sealed by the upper seal; the second piston pressure plate and the lower part of the magnetic core are sealed by the lower seal.

[0005] Preferably, the upper and lower end surfaces of the magnetic core are provided with grooves, the lower part of the first piston pressure plate and the upper part of the second piston pressure plate are provided with bosses, and the first piston pressure plate, the second piston pressure plate and the magnetic core are plugged in through the cooperation of the bosses and the grooves; the upper seal is arranged between the first piston pressure plate and the magnetic core; the lower seal is arranged between the second piston pressure plate and the magnetic core.

[0006] Preferably, the upper sealing member and the lower sealing member are both annular sealing gaskets, and the sealing gaskets are sleeved on the boss.

[0007] Preferably, the upper seal and the lower seal are both sealing rings, and sealing ring grooves are processed on the lower part of the first piston pressure plate, the upper part of the second piston pressure plate, and the upper and lower end surfaces of the magnetic core, and the sealing ring is arranged in the sealing ring groove.

[0008] Preferably, it also includes a piston rod, which passes through the first piston pressure plate and is fixedly connected to the magnetic core. The valve assembly includes a valve plate, a pre-stressed rebound member and a retaining frame. The valve plate is used to cover the previous through hole. The retaining frame is fixed on the piston rod. The two ends of the pre-stressed rebound member are respectively abutted against the valve plate and the retaining frame. The pre-stressed rebound member is used to apply a pre-tightening force to the valve plate to keep the previous through hole in a normally closed state.

[0009] The beneficial effects of the present invention are as follows: the piston valve of a shock absorber provided by the above technical solution allows magnetorheological fluid to flow through the main channel and into the secondary channel during the compression stroke. Since the first piston pressure plate is sealed to the upper part of the magnetic core by the upper seal, and the second piston pressure plate is sealed to the lower part of the magnetic core by the lower seal, the magnetorheological fluid in the secondary channel will not leak into the main channel. The magnetorheological fluid in the secondary channel opens the normally closed structure of the upper through hole under the action of the magnetorheological fluid, and the damping force generated by the shock absorber is relatively small. During the rebound stroke, the valve assembly closes the upper through hole, and the magnetorheological fluid cannot flow through the secondary channel. The magnetorheological fluid can only flow through the main channel, and the damping force generated by the shock absorber is relatively large. The utility model has a simple structure, realizes asymmetric controllable damping force, and solves the problem that the piston valve of the existing magnetorheological shock absorber may have a leakage channel between the main channel and the secondary channel, so that the magnetorheological fluid cannot open the valve assembly of the secondary channel, resulting in the shock absorber being unable to achieve asymmetric controllable damping characteristics.

[0010] The present invention will become more clear through the following description in conjunction with the accompanying drawings, which are used to explain embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Shown is the overall structural diagram of the piston valve.

[0012] Figure 2 Shown Figure 1 Cross-sectional view of AA in the figure.

[0013] Figure 3 Shown is a structural separation diagram of the piston valve.

[0014] Figure 4 Shown is a structural separation diagram of the first piston pressure plate and valve assembly.

[0015] Figure 5 Shown is a top view of the first piston pressure plate.

[0016] Figure 6 Shown is a cross-sectional view of BB in 5.

[0017] Figure 7 Shown is a structural separation diagram of the second piston pressure plate and throat plug.

[0018] Figure 8 Shown is a cross-sectional view of the second piston pressure plate and throat plug after separation.

[0019] Figure 9 Shown is a cross-sectional view of a magnetorheological damper. DETAILED DESCRIPTION

[0020] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0021] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0022] In the description of this utility model, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0023] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0024] refer to Figures 1 to 8A piston valve includes a piston housing 100, a magnetic core 400, a piston rod 500, a first piston pressure plate 300, a second piston pressure plate 200 and a valve assembly. The first piston pressure plate 300 and the second piston pressure plate 200 fix the magnetic core 400 in the piston housing 100 at the upper and lower ends. The gap between the magnetic core 400 and the inner wall of the piston housing 100 forms a main channel 110. The first piston pressure plate 300 and the second piston pressure plate 200 are respectively provided with an upper main through hole 301 and a lower main through hole 201. The main channel 110 is connected to the upper main through hole 301 and the lower main through hole 201 respectively. 01 connection setting; the piston rod 500 passes through the first piston pressure plate 300 and is fixedly connected to the magnetic core 400, and a secondary channel 401 is provided in the magnetic core 400. The first piston pressure plate 300 and the second piston pressure plate 200 are respectively provided with an upper through hole 302 and a lower through hole 202. The secondary channel 401 is connected to the upper through hole 302 and the lower through hole 202 respectively. The valve assembly is provided above the first piston pressure plate 300. The valve assembly is used to cover the upper through hole 302. The valve assembly is a normally closed structure that can open the upper through hole 302 under the pressure of the magnetorheological fluid. During the compression stroke, the magnetorheological fluid can flow through the main channel 110 and can also enter the secondary channel 401. The magnetorheological fluid in the secondary channel 401 opens the normally closed structure of the upper through hole 302, such as Figure 2 As shown by the arrow in , the damping force generated by the shock absorber is relatively small at this time; during the rebound stroke, the valve assembly closes the upper through hole 302, the magnetorheological fluid cannot flow through the secondary channel 401, and the magnetorheological fluid can only flow through the main channel 110. At this time, the damping force generated by the shock absorber is relatively large; the utility model has a simple structure, realizes asymmetric controllable damping force, and solves the problem of asymmetry of compression and recovery damping forces of the piston valve in the existing magnetorheological shock absorber.

[0025] In one embodiment, the magnetic core 400 is provided with a plurality of secondary channels 401, and the first piston pressure plate 300 and the second piston pressure plate 200 are respectively provided with a plurality of upper through holes 302 and a plurality of lower through holes 202, and the first piston pressure plate 300 and the second piston pressure plate 200 are connected to the secondary channels 401 in a one-to-one correspondence; it also includes a plurality of throat plug groups, and the throat plug group includes throat plugs 210 with the same number as the lower through holes 202, and the throat plugs 210 are detachably installed in the lower through holes 202, and throat plug through holes 211 are provided in the throat plugs 210, and the inner diameters of the throat plug through holes 211 of the throat plugs 210 in the same throat plug group are the same, and the inner diameters of the throat plug through holes 211 of the throat plugs 210 in the two groups of throat plug groups are different. A plurality of secondary channels 401 are provided in the magnetic core 400, and all the secondary channels 401 are arranged in a ring-shaped distribution around the axis of the magnetic core 400. During the compression stroke, the magnetorheological fluid enters the secondary channels 401, so that the piston valve is subjected to uniform force, thereby avoiding uneven force on the piston valve and generating radial force that damages the connection structure of the piston rod 500, the magnetic core 400 and the shock absorber cylinder, thereby ensuring the service life. Since the apertures of the upper through hole 302, the lower through hole 202 and the secondary channel 401 remain unchanged, the flow rate of the magnetorheological fluid flowing through the secondary channel 401 in the conventional shock absorber is constant. When testing or producing the shock absorber, in response to different damping force requirements, this embodiment provides multiple groups of throat plug groups, and the throat plug group includes throat plugs 210 with the same number as the lower through holes 202. The throat plugs 210 are detachably installed in the lower through holes 202. The throat plugs 210 are provided with throat plug through holes 211. The inner diameters of the throat plug through holes 211 of the throat plugs 210 in the same throat plug group are the same; when different damping force requirements are required, all the throat plugs 210 can be removed from the lower through holes 202, and a throat plug group with a suitable inner diameter of the throat plug through holes 211 is selected, and then the throat plugs 210 of this group are installed one by one in the lower through holes 202. An internal thread can be machined into the secondary through-hole 202, and an external thread can be machined into the outer peripheral wall of the throat plug 210, so that the throat plug 210 can be detachably connected to the secondary through-hole 202 by screwing the threads together. To facilitate installation and removal, the two side ports of the throat plug 210 can also be machined into internal hexagonal holes, and the throat plug through-hole 211 is located between the two side ports, so that the throat plug 210 can be removed and installed using a conventional internal hexagonal wrench. In addition, since the two side ports of the throat plug 210 are machined into internal hexagonal holes, the installation direction of the throat plug 210 does not need to be considered during installation, further improving installation convenience.

[0026] In one embodiment, a plug group is further included, wherein the plug group includes plugs of the same number as the secondary through-holes 202, and the plugs are detachably installed in the secondary through-holes 202. When testing or producing shock absorbers, depending on different damping force requirements, it is sometimes not necessary for the magnetorheological fluid to flow through the secondary channel 401. This embodiment also provides a plug group, the structure of which is similar to that of the throat plug 210, and an external thread is also machined on the outer peripheral wall, and the plug is detachably connected to the secondary through-hole 202 by screwing the thread; the two side ports of the plug are machined into internal hexagonal holes, and the internal hexagonal holes of the two side ports are solid structures, so as to achieve the closure of the secondary through-hole 202.

[0027] In one embodiment, a sealing assembly is further included, which includes an upper seal 410 and a lower seal 420. The first piston pressure plate 300 is sealed and connected to the upper part of the magnetic core 400 through the upper seal 410; the second piston pressure plate 200 is sealed and connected to the lower part of the magnetic core 400 through the lower seal 420. During the compression stroke, the magnetorheological fluid can flow through the main channel 110 and enter the secondary channel 401. The magnetorheological fluid in the secondary channel 401 opens the normally closed structure of the upper through hole 302. In order to prevent the magnetorheological fluid from entering the secondary channel 401, the valve assembly of the upper through hole 302 is not opened, and flows into the main channel 110 along the gap between the first piston platen 300 and the magnetic core 400, or the gap between the second piston platen 200 and the magnetic core 400. A sealing assembly is required. The sealing assembly includes an upper seal 410 and a lower seal 420. The first piston platen 300 and the upper part of the magnetic core 400 are sealed together by the upper seal 410; the second piston platen 200 and the lower part of the magnetic core 400 are sealed together by the lower seal 420. The upper seal 410 and the lower seal 420 can both be in the form of a sealing gasket or a sealing ring. The upper and lower end surfaces of the magnetic core 400 can be provided with grooves, and the lower part of the first piston pressure plate 300 and the upper part of the second piston pressure plate 200 are provided with bosses. Through the cooperation of the bosses and the grooves, the coaxiality of the first piston pressure plate 300, the magnetic core 400 and the second piston pressure plate 200 is improved. When the upper seal 410 and the lower seal 420 use sealing gaskets, they can be respectively mounted on the lower part of the first piston pressure plate 300 and the upper part of the second piston pressure plate 200; when the upper seal 410 and the lower seal 420 use sealing rings, sealing ring grooves need to be processed on the lower part of the first piston pressure plate 300, the upper part of the second piston pressure plate 200, and the upper and lower end surfaces of the magnetic core 400, and then the sealing ring is placed in the sealing ring groove for sealing.

[0028] In one embodiment, the valve assembly includes a valve disc 310, a preloaded resilient member 320, and a retainer 330. The valve disc 310 is used to shield the upper through hole 302. The retainer 330 is fixed to the piston rod 500. The two ends of the preloaded resilient member 320 respectively abut the valve disc 310 and the retainer 330. The preloaded resilient member 320 is used to apply a preloaded force to the valve disc 310 to keep the upper through hole 302 in a normally closed state. The valve disc 310 has a circular ring structure. The two ends of the preloaded resilient member 320 respectively abut the valve disc 310 and the retainer 330. The preloaded resilient member 320 is used to apply a preloaded force to the valve disc 310 to keep the upper through hole 302 in a normally closed state. The pre-stressed rebound member 320 can adopt a tower spring structure, which has a large compression capacity. Therefore, a shorter tower spring can achieve a larger opening range of the upper through hole 302, making the valve assembly structure compact and stable. The upper part of the first piston pressure plate 300 is axially extended upward and provided with an upper pipe section 304. The outer peripheral wall of the upper pipe section 304 is radially extended outward and provided with a circle of annular grooves 303. The upper part of the upper pipe section 304 is provided with an external thread. The upper part of the retainer 330 is a nut structure with an internal thread. The lower part of the retainer 330 is axially extended downward and provided with a lower pipe section 331. The retainer 330 is detachably connected to the first piston pressure plate 300 by screwing. The retainer 330 is installed on the first piston When the first piston pressure plate 300 is pressed, the lower tube section 331 of the retainer 330 can extend into the annular groove 303. After the retainer 330 is installed on the first piston pressure plate 300, a certain gap is left between the lower end surface of the lower tube section 331 and the bottom surface of the annular groove 303. This prevents the retainer 330 from being restricted from further downward rotation after the lower end surface of the lower tube section 331 abuts the bottom surface of the annular groove 303 during installation, resulting in the valve disc 310 not being able to apply the preset preload force by the tower spring. In addition, the valve disc 310 adopts a circular ring structure and is sleeved on the lower tube section 331. The lower tube section 331 and the valve disc 310 have a clearance fit, and the lower tube section 331 serves as a vertical guide for the valve disc 310.

[0029] In one embodiment, the upper portion of the first piston pressure plate 300 is provided with two pressing surfaces 305. The upper through hole 302 is located between the two pressing surfaces 305. The lower end surface of the valve disc 310 is simultaneously abutted against both pressing surfaces 305. The upper through hole 302 is located between the two pressing surfaces 305, providing support for the valve disc 310. To reduce weight and cost, an annular groove is provided between the two pressing surfaces 305, with the upper through hole 302 located at the bottom of the annular groove. The valve disc 310 has a circular ring structure, and the lower end surface of the valve disc 310 simultaneously abuts against both pressing surfaces 305, thereby shielding the upper through hole 302.

[0030] In one embodiment, a support step 306 is provided between the two pressing surfaces 305. To increase the strength of the first piston platen 300 and prevent the valve disc 310 from being pressed into the annular groove, multiple support steps 306 are provided at intervals within the annular groove. All support steps 306 are arranged in an annular pattern along the axis of the first piston platen 300.

[0031] In one embodiment, the valve disc 310 is provided with a bypass hole 311. Under the force of the preload resilient member 320, the valve disc 310 abuts against the two pressing surfaces 305. The bypass hole 311 is connected to the upper through hole 302. Several bypass holes 311 with smaller apertures are spaced apart on the valve disc 310. Under the force of the preload resilient member 320, the valve disc 310 abuts against the two pressing surfaces 305. The bypass holes 311 are connected to the upper through hole 302. When the force applied by the magnetorheological fluid does not reach the force required to open the preload resilient member 320, a small amount of magnetorheological fluid can flow through the secondary channel 401, the upper through hole 302, and the bypass hole 311. When the piston valve moves at low speeds, the piston valve can generate a small damping force. This piston valve is used in a magnetorheological shock absorber in an automobile to improve the vehicle's rolling comfort at low speeds.

[0032] refer to Figure 9This embodiment further discloses a magnetorheological damper, comprising a cylinder 600 with an opening at one end, a guide seat 660 being provided at the opening of the cylinder 600, and the piston valve as described above, wherein the piston valve divides the cylinder 600 into a compression chamber 630 and a rebound chamber 620, and the piston rod 500 extends out of the cylinder 600 through the guide seat 660; the upper main through hole 301 is connected to the rebound chamber 620; and the lower main through hole 201 and the lower through hole 202 are both connected to the compression chamber 630. The piston valve divides the cylinder 600 into a compression chamber 630 and a rebound chamber 620. The compression chamber 630 and the rebound chamber 620 are filled with magnetorheological fluid. During the compression stroke, the magnetorheological fluid in the compression chamber 630 can flow into the rebound chamber 620 through the main channel 110, and can also enter the secondary channel 401. The magnetorheological fluid in the secondary channel 401 opens the normally closed structure of the upper through hole 302, and the magnetorheological fluid in the compression chamber 630 enters the rebound chamber 620 through the secondary channel 401. At this time, the damping force generated by the shock absorber is relatively small; during the rebound stroke, the valve assembly closes the upper through hole 302, and the magnetorheological fluid cannot flow through the secondary channel 401. The magnetorheological fluid in the rebound chamber 620 can only flow into the compression chamber 630 through the main channel 110. At this time, the damping force generated by the shock absorber is relatively large. A floating piston 640 is also provided in the magnetorheological shock absorber. The floating piston 640 divides the compression chamber 630 into a liquid chamber and a gas chamber 650. The floating piston 640 and the bottom of the cylinder 600 form a gas chamber 650, which is filled with high-pressure gas; the liquid chamber is between the floating piston 640 and the piston valve, which is filled with magnetorheological fluid.

[0033] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A piston valve for a shock absorber, characterized in that: include: Piston housing: the piston housing is in a ring shape; Magnetic core: The magnetic core is fixedly installed in the piston housing through the first piston pressure plate and the second piston pressure plate. The gap between the magnetic core and the inner wall of the piston housing forms a main channel. The first piston pressure plate and the second piston pressure plate are both provided with a main through hole for the passage of magnetorheological fluid; a secondary channel is provided in the magnetic core. The first piston pressure plate and the second piston pressure plate are respectively provided with an upper through hole and a lower through hole. The secondary channel is connected to the upper through hole and the lower through hole respectively; Valve assembly: The valve assembly is arranged above the first piston pressure plate, and is used to cover the upper through hole. The valve assembly is a normally closed structure that can open the upper through hole under the pressure of magnetorheological fluid; Sealing assembly: The sealing assembly includes an upper seal and a lower seal. The first piston pressure plate is sealed and connected to the upper part of the magnetic core through the upper seal; the second piston pressure plate is sealed and connected to the lower part of the magnetic core through the lower seal.

2. The piston valve of a shock absorber according to claim 1, characterized in that: The upper and lower end surfaces of the magnetic core are both provided with grooves, and the lower part of the first piston pressure plate and the upper part of the second piston pressure plate are both provided with bosses. The first piston pressure plate, the second piston pressure plate and the magnetic core are plugged in through the cooperation of the bosses and the grooves; the upper seal is arranged between the first piston pressure plate and the magnetic core; the lower seal is arranged between the second piston pressure plate and the magnetic core.

3. The piston valve of a shock absorber according to claim 2, characterized in that: The upper sealing member and the lower sealing member both adopt an annular sealing gasket, and the sealing gasket is sleeved on the boss.

4. The piston valve of a shock absorber according to claim 2, characterized in that: The upper seal and the lower seal are both sealing rings. The lower part of the first piston pressure plate, the upper part of the second piston pressure plate, and the upper and lower end surfaces of the magnetic core are all processed with sealing ring grooves, and the sealing ring is arranged in the sealing ring grooves.

5. The piston valve of a shock absorber according to claim 1, characterized in that: It also includes a piston rod, which passes through the first piston pressure plate and is fixedly connected to the magnetic core. The valve assembly includes a valve plate, a pre-stressed rebound member and a retaining frame. The valve plate is used to cover the previous through hole. The retaining frame is fixed on the piston rod. The two ends of the pre-stressed rebound member are respectively abutted against the valve plate and the retaining frame. The pre-stressed rebound member is used to apply a pre-tightening force to the valve plate to keep the previous through hole in a normally closed state.

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