阅读说明：本技术 一种轨道车辆油压减振器及活塞组件 (Rail vehicle oil pressure shock absorber and piston assembly ) 是由 方照根 刘畅 陈春鹏 宋自帅 王志伟 于 2021-09-17 设计创作，主要内容包括：本发明的实施例提供了一种轨道车辆油压减振器及活塞组件,涉及减振器结构技术领域。本发明的实施例提供的活塞组件包括活塞杆、活塞体、阀挡及阻尼阀组。活塞体和阀挡设置在活塞杆的同一端,且阻尼阀组设置在活塞体和阀挡之间,活塞体、阀挡以及阻尼阀组形成供液压油流动的通道。同时阻尼阀组包括第一薄阀片、第二薄阀片以及功能阀片,第一薄阀片的厚度和第二薄阀片的厚度均小于功能阀片的厚度,且沿阀挡至活塞体的方向,第一薄阀片、功能阀片和第二薄阀片依次设置。通过对阻尼阀组的设置,使得通过一个阻尼阀组即可实现压缩和拉伸行程的阻尼力的产生,该活塞组件的长度更小,从而减小了油压减振器的死行程。(The embodiment of the invention provides an oil pressure shock absorber and a piston assembly of a railway vehicle, and relates to the technical field of shock absorber structures. The piston assembly provided by the embodiment of the invention comprises a piston rod, a piston body, a valve stop and a damping valve group. The piston body and the valve stop are arranged at the same end of the piston rod, the damping valve group is arranged between the piston body and the valve stop, and the piston body, the valve stop and the damping valve group form a channel for flowing of hydraulic oil. Meanwhile, the damping valve group comprises a first thin valve plate, a second thin valve plate and a functional valve plate, the thickness of the first thin valve plate and the thickness of the second thin valve plate are smaller than that of the functional valve plate, and the first thin valve plate, the functional valve plate and the second thin valve plate are sequentially arranged along the direction from the valve stop to the piston body. Through the setting to the damping valves for can realize the production of the damping force of compression and tensile stroke through a damping valves, this piston assembly's length is littleer, thereby has reduced oil hydraulic shock absorber's dead stroke.)

1. A piston assembly for a rail vehicle oleo damper (10), said piston assembly (100) comprising a piston rod (110), a piston body (140), a valve stop (120), and a damping valve pack (130); the piston body (140) and the valve stop (120) are arranged at the same end of the piston rod (110), the damping valve group (130) is arranged between the valve stop (120) and the piston body (140), the valve stop (120) and the damping valve group (130) form a channel (160) for hydraulic oil to flow;

damping valves (130) include first thin valve block (131), second thin valve block (132) and function valve block, the thickness of first thin valve block (131) is less than the thickness of function valve block, the thickness of second thin valve block (132) is less than the thickness of function valve block, and follows the direction of valve fender (120) to piston body (140), first thin valve block (131) function valve block with second thin valve block (132) set gradually.

2. The piston assembly according to claim 1, wherein the functional valve plate comprises a first main valve plate, a second main valve plate and a relief valve plate (139), the thickness of the first main valve plate is greater than the thickness of the first thin valve plate (131) and the thickness of the second thin valve plate (132), and the thickness of the second main valve plate is greater than the thickness of the first thin valve plate (131) and the thickness of the second thin valve plate (132); along the direction from the valve stop (120) to the piston body (140), the first thin valve plate (131), the first main valve plate, the unloading valve plate (139), the second main valve plate and the second thin valve plate (132) are arranged in sequence.

3. The piston assembly of claim 2, characterized in that a throttle groove (138) is arranged on the relief valve plate (139), and the throttle groove (138) forms an opening at the inner edge or the outer edge of the relief valve plate (139).

4. The piston assembly of claim 1, wherein the functional valve plate comprises a first relief valve plate (133), a second relief valve plate (136) and a main valve plate (135), and the thickness of the main valve plate (135) is greater than the thickness of the first thin valve plate (131) and the thickness of the second thin valve plate (132); along the direction from the valve stop (120) to the piston body (140), the first thin valve plate (131), the first unloading valve plate (133), the main valve plate (135), the second unloading valve plate (136) and the second thin valve plate (132) are arranged in sequence.

5. The piston assembly of claim 1, wherein the piston rod (110) comprises a rod body (111) and a connecting section (112) arranged at one end of the rod body (111), and a limit step is formed between the rod body (111) and the connecting section (112); one of the piston body (140) and the valve stop (120) abuts against the limit step, and the other of the piston body (140) and the valve stop (120) is in threaded connection with the connecting section (112) so as to press the damping valve group (130) between the piston body (140) and the valve stop (120).

6. The piston assembly of claim 5, characterized in that the piston body (140) has an interference surface (147) with the second thin blade (132), the interference surface (147) being a flat surface.

7. The piston assembly of claim 1, wherein a first flow passage (121) is formed in the valve stop (120), a throttling gap (162) is formed in the inner periphery of the damping valve group (130), and a communication gap (161) for communicating the first flow passage (121) with the throttling gap (162) is formed between the first thin valve plate (131) and the valve stop (120); the piston body (140) is provided with a second flow passage (141), and the first flow passage (121), the communication gap (161), the throttling gap (162) and the second flow passage (141) are sequentially communicated to form the passage (160).

8. The piston assembly according to claim 7, characterized in that a protrusion (122) is arranged on an end surface of the valve stop (120) close to the first thin valve plate (131), and the protrusion (122) abuts against the first thin valve plate (131) to form the communication gap (161) between the end surface and the first thin valve plate (131).

9. The piston assembly of claim 7, wherein the second flow passage (141) includes a small diameter section (142) and large diameter sections (143) disposed at both ends of the small diameter section (142).

10. The piston assembly of claim 1, wherein the piston assembly (100) further comprises a seal assembly (150), a radial outer periphery of the piston body (140) is provided with a seal groove (144), the seal assembly (150) is installed in the seal groove (144), and the seal assembly (150) is used for guiding the movement of the piston body (140) and sealing the piston body at high pressure.

11. The piston assembly of claim 10, wherein the seal assembly (150) includes an O-ring (151) and a quad ring (152), the quad ring (152) having a width greater than a width of the O-ring (151); the sealing groove (144) comprises a first groove part (145) used for installing the square sealing ring (152) and a second groove part (146) used for installing the O-shaped sealing ring (151), and the second groove part (146) is arranged at the bottom of the first groove part (145) in an opening mode.

12. A rail vehicle oleo damper, characterized in that the rail vehicle oleo damper (10) comprises a pressure cylinder (211) and a piston assembly (100) according to any of claims 1-11, the piston body (140) of the piston assembly (100) being a sliding fit in the pressure cylinder (211).

Technical Field

The invention relates to the technical field of shock absorber structures, in particular to an oil pressure shock absorber and a piston assembly of a railway vehicle.

Background

The oil pressure shock absorber is used as a key part of a railway vehicle bogie, and the performance of the oil pressure shock absorber directly influences the running safety, stability and comfort of the whole vehicle. The damping characteristic of the oil pressure shock absorber can meet the requirement of the whole vehicle dynamic performance of the rail vehicle, the force-speed characteristic is stable, reliable and distortion-free, and the product is convenient to produce and debug. Meanwhile, the working stroke (the difference between the maximum tensile displacement and the maximum compression displacement) of the oil pressure damper is enough to meet the use requirement of the whole railway vehicle.

However, in the prior art, the overall structural size of the piston assembly of the oil pressure damper is large, which finally results in that the dead stroke (the sum of the lengths of all parts in the pressure cylinder of the damper) of the oil pressure damper is large, and the operating requirements of the rail vehicle are difficult to meet.

Disclosure of Invention

The invention aims to provide a railway vehicle oil pressure damper and a piston assembly, which can reduce the dead stroke of the oil pressure damper and meet the operating requirements of a railway vehicle.

Embodiments of the invention may be implemented as follows:

the embodiment of the invention provides a piston assembly for an oil pressure shock absorber of a railway vehicle, which comprises a piston rod, a piston body, a valve stop and a damping valve group, wherein the piston rod is fixedly connected with the piston rod; the piston body and the valve stop are arranged at the same end of the piston rod, the damping valve group is arranged between the valve stop and the piston body, the valve stop and the damping valve group form a channel for hydraulic oil to flow;

the damping valve group comprises a first thin valve plate, a second thin valve plate and a functional valve plate, wherein the thickness of the first thin valve plate is smaller than that of the functional valve plate, the thickness of the second thin valve plate is smaller than that of the functional valve plate, the valve block is arranged in the direction from the valve to the piston body, and the first thin valve plate, the functional valve plate and the second thin valve plate are sequentially arranged.

Optionally, the functional valve plate includes a first main valve plate, a second main valve plate and an unloading valve plate, the thickness of the first main valve plate is greater than the thickness of the first thin valve plate and the thickness of the second thin valve plate, and the thickness of the second main valve plate is greater than the thickness of the first thin valve plate and the thickness of the second thin valve plate; and the first thin valve plate, the first main valve plate, the unloading valve plate, the second main valve plate and the second thin valve plate are sequentially arranged along the direction from the valve to the piston body.

Optionally, the functional valve plate includes a first unloading valve plate, a second unloading valve plate and a main valve plate, and the thickness of the main valve plate is greater than the thickness of the first thin valve plate and the thickness of the second thin valve plate; and the first thin valve plate, the first unloading valve plate, the main valve plate, the second unloading valve plate and the second thin valve plate are sequentially arranged along the direction from the valve to the piston body.

Optionally, a throttle groove is arranged on the unloading valve plate, and an opening is formed in the inner edge or the outer edge of the unloading valve plate by the throttle groove.

Optionally, the piston rod includes a rod body and a connecting section arranged at one end of the rod body, and a limiting step is formed between the rod body and the connecting section; one of the piston body and the valve stop is abutted against the limiting step, and the other of the piston body and the valve stop is in threaded connection with the connecting section so as to tightly press the damping valve group between the piston body and the valve stop.

Optionally, the piston body has an interference surface that interferes with the second thin valve sheet, and the interference surface is a plane.

Optionally, a first flow channel is formed in the valve stop, a throttling gap is formed in the inner periphery of the damping valve group, and a communicating gap for communicating the first flow channel with the throttling gap is formed between the first thin valve plate and the valve stop; the piston body is provided with a second flow passage, and the first flow passage, the communication gap, the throttling gap and the second flow passage are sequentially communicated to form the passage.

Optionally, a protrusion is arranged on an end surface of the valve stopper close to one side of the first thin valve plate, and the protrusion abuts against the first thin valve plate to form the communication gap between the end surface and the first thin valve plate.

Optionally, the second flow channel includes a small-diameter section and a large-diameter section disposed at two ends of the small-diameter section.

Optionally, the piston assembly further includes a sealing assembly, a sealing groove is formed in the radial periphery of the piston body, the sealing assembly is installed in the sealing groove, and the sealing assembly is used for guiding the movement of the piston body and sealing the piston body at high pressure.

Optionally, the sealing assembly includes an O-ring and a quad ring, and the quad ring has a width greater than that of the O-ring; the seal groove comprises a first groove part used for installing the square seal ring and a second groove part used for installing the O-shaped seal ring, and the second groove part is arranged at the bottom of the first groove part.

The embodiment of the invention also provides the rail vehicle oil pressure shock absorber which comprises a pressure cylinder and the piston assembly, wherein a piston body of the piston assembly is in sliding fit with the pressure cylinder.

The rail vehicle oil pressure damper and the piston assembly have the advantages that:

the embodiment of the invention provides a piston assembly for a rail vehicle oil pressure shock absorber, which comprises a piston rod, a piston body, a valve stop and a damping valve group. The piston body and the valve stop are arranged at the same end of the piston rod, the damping valve group is arranged between the piston body and the valve stop, and the piston body, the valve stop and the damping valve group form a channel for flowing of hydraulic oil. Meanwhile, the damping valve group comprises a first thin valve plate, a second thin valve plate and a functional valve plate, the thickness of the first thin valve plate and the thickness of the second thin valve plate are smaller than that of the functional valve plate, and the first thin valve plate, the functional valve plate and the second thin valve plate are sequentially arranged along the direction from the valve stop to the piston body. Through the setting to the damping valves for can realize the production of the damping force of compression and tensile stroke through a damping valves, compare in prior art through the structural style that two damping valves produced compression damping force and tensile damping force respectively, this piston assembly's length is littleer, thereby has reduced the dead stroke of oil pressure shock absorber, under the unchangeable condition of oil pressure shock absorber's pressure cylinder size, has increased oil pressure shock absorber's working stroke, helps satisfying rail vehicle operation requirement.

Embodiments of the present invention also provide a rail vehicle oil pressure damper, which includes the above-mentioned piston assembly. Because this rail vehicle oil pressure shock absorber includes foretell piston assembly, consequently also have the dead stroke little, the working stroke is big, can satisfy the beneficial effect that rail vehicle application required.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic structural diagram of a rail vehicle oil damper according to an embodiment of the invention;

FIG. 2 is a schematic structural diagram of a piston assembly provided in accordance with an embodiment of the present invention;

FIG. 3 is an enlarged view of a portion of the structure at III in FIG. 2;

FIG. 4 is a schematic structural diagram of a first relief valve plate in the piston assembly according to an embodiment of the present invention;

FIG. 5 is a structural schematic diagram of a second relief valve plate in the piston assembly according to the embodiment of the present invention;

FIG. 6 is a schematic view of a valve stop of the piston assembly shown from a first perspective in accordance with an embodiment of the present invention;

FIG. 7 is a schematic diagram of a valve stop of the piston assembly shown from a second perspective in accordance with an embodiment of the present invention;

fig. 8 is an enlarged view of a portion of the structure at viii in fig. 2.

Icon: 10-rail vehicle oil pressure vibration absorber; 100-a piston assembly; 110-a piston rod; 111-a rod body; 112-a connecting segment; 120-valve stop; 121-a first flow channel; 122-a protrusion; 130-damping valve group; 131-a first thin valve sheet; 132-a second thin valve sheet; 133-a first relief valve plate; 134-first throttling groove; 135-main valve plate; 136-second relief valve plate; 137-a second throttle groove; 138-a throttling groove; 139-unloading valve plate; 140-a piston body; 141-a second flow channel; 142-a small diameter section; 143-large diameter section; 144-a sealing groove; 145-a first groove portion; 146-a second trough portion; 147-an interference surface; 150-a seal assembly; 151-O-ring seal; 152-square sealing ring; 160-channel; 161-communication gap; 162-throttle gap; 163-a support block; 211-a pressure cylinder; 212-a first chamber; 213-a second chamber; 214-a cylinder head assembly; 215-base valve assembly.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. indicate an orientation or a positional relationship based on that shown in the drawings or that the product of the present invention is used as it is, this is only for convenience of description and simplification of the description, and it does not indicate or imply that the device or the element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention.

Furthermore, the appearances of the terms "first," "second," and the like, if any, are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

It should be noted that the features of the embodiments of the present invention may be combined with each other without conflict.

In an existing rail vehicle oil pressure shock absorber, a piston assembly is provided with a compression damping valve group and a tension damping valve group, damping force is generated through the compression damping valve group in a compression stroke, and damping force is generated through the tension damping valve group in a tension stroke. The inventor researches and discovers that the structure of the piston assembly causes the overall structure size of the piston assembly to be larger, and finally causes the dead stroke of the railway vehicle oil pressure damper to be larger, so that the application requirement of the railway vehicle is difficult to meet. The present embodiment provides a rail vehicle oil damper and piston assembly to improve the above problems in the prior art.

Fig. 1 is a schematic structural diagram of a rail vehicle oil pressure damper 10 according to the present embodiment, fig. 2 is a schematic structural diagram of a piston assembly 100 according to the present embodiment, and fig. 3 is an enlarged schematic partial structural diagram at iii in fig. 2. Referring to fig. 1-3 in combination, the present embodiment provides a piston assembly 100, and accordingly, a rail vehicle oil damper 10.

Railway vehicle oleo damper 10 includes piston assembly 100 and also includes pressure tube 211. One end of the piston assembly 100, at which the piston body 140 is disposed, is located in the pressure cylinder 211 and is in sliding engagement with the pressure cylinder 211, thereby dividing the inner space of the pressure cylinder 211 into a first chamber 212 and a second chamber 213 located at both sides of the piston body 140. An end of the first chamber 212 remote from the second chamber 213 is provided with a cylinder head assembly 214, through which the piston rod 110 of the piston assembly 100 passes to protrude out of the pressure cylinder 211. The end of the second chamber 213 away from the first chamber 212 is provided with a base valve assembly 215, and the second chamber 213 is communicated with the oil storage chamber through the base valve assembly 215, so that the high-pressure hydraulic oil in the second chamber 213 can enter and exit the oil storage chamber through the base valve assembly 215 during the movement of the piston assembly 100 relative to the pressure tube 211.

Piston assembly 100 includes a piston rod 110, a piston body 140, a valve stop 120, and a damping valve assembly 130. Piston body 140 and valve stop 120 are disposed on the same end of piston rod 110, and damping valve block 130 is disposed between piston body 140 and valve stop 120, with piston body 140, valve stop 120, and damping valve block 130 forming a passage 160 for the flow of hydraulic fluid. Meanwhile, the damping valve set 130 includes a first thin valve plate 131, a second thin valve plate 132 and a functional valve plate, the thickness of the first thin valve plate 131 and the thickness of the second thin valve plate 132 are both smaller than the thickness of the functional valve plate, and the first thin valve plate 131, the functional valve plate and the second thin valve plate 132 are sequentially arranged along the direction from the valve stop 120 to the piston body 140. Through the setting to damping valves 130 for can realize the production of the damping force of compression and tensile stroke through a damping valves 130, compare in the prior art through the structural style that two damping valves produced compression damping force and tensile damping force respectively, this piston assembly 100's length is littleer, thereby the dead stroke of rail vehicle oil pressure shock absorber 10 has been reduced, under the unchangeable condition of pressure cylinder 211 size of rail vehicle oil pressure shock absorber 10, the working stroke of rail vehicle oil pressure shock absorber 10 has been increased, help satisfying rail vehicle operation requirement.

The piston assembly 100 provided in the present embodiment is further described below:

referring to fig. 2 and fig. 3, in the present embodiment, the piston assembly 100 includes only one damping valve set 130, the damping valve set 130 is disposed on one side of the piston body 140, and correspondingly, the number of the valve stops 120 is also set to one, and the valve stop 120 is disposed on one side of the damping valve set 130 away from the piston body 140, so that the positioning and the pre-pressing effects on the damping valve set 130 are realized through the cooperation of the valve stop 120 and the piston body 140.

Specifically, the piston rod 110 includes a rod body 111 and a connecting section 112 disposed at one end of the rod body 111, and a radial dimension of the connecting section 112 is smaller than a radial dimension of the rod body 111, so that a limiting step is formed between the rod body 111 and the connecting section 112. The valve stop 120 abuts against the limiting step, so that the valve stop 120 is positioned through the limiting step. The damping valve set 130 and the piston body 140 are both sleeved on the connecting section 112, and one end of the damping valve set 130 abuts against the valve stop 120, and the other end abuts against the piston body 140, so that the limiting of the damping valve set 130 is realized. Meanwhile, the piston body 140 is provided with an internal thread, the connecting section 112 is provided with an external thread, the piston body 140 and the connecting section 112 are fixedly connected through the threaded connection of the internal thread and the external thread, and the compression of the damping valve set 130 and the adjustment of the pre-pressure can be realized by screwing the piston body 140.

Moreover, since the damping valve set 130 is compressed by the piston body 140 and the valve stop 120, the collision surface 147 of the piston body 140 and the second thin valve plate 132 of the damping valve set 130 is a plane, and the pre-compression of the damping valve set 130 can be realized. The piston body 140 has a simpler structure and is convenient to produce and process.

It should be noted that, in this embodiment, the valve stop 120 is disposed on one side of the damping valve set 130 relatively close to the rod body 111, and the piston body 140 is provided with an internal thread, so as to realize the fixed connection and the compression of the damping valve set 130 through the screw connection of the piston body 140 and the connecting section 112, it can be understood that, in other embodiments, the piston body 140 may also be disposed on one side of the damping valve set 130 relatively close to the rod body 111 according to requirements, and then realize the fixed connection and the compression of the damping valve set 130 through the screw connection of the valve stop 120 and the connecting section 112.

The damping valve set 130 includes a first thin valve plate 131, a functional valve plate and a second thin valve plate 132, the first thin valve plate 131 and the second thin valve plate 132 are disposed on two sides of the functional valve plate, so that in the process of the extension stroke and the compression stroke of the piston assembly 100, when the piston assembly 100 moves at a low speed, the first thin valve plate 131 and the second thin valve plate 132 respectively generate damping forces to perform initial throttling, and meanwhile, the functional valve plate disposed between the first thin valve plate 131 and the second thin valve plate 132 can generate damping forces in corresponding directions according to the moving direction of the piston assembly 100, so as to generate damping forces corresponding to the speed when the piston assembly 100 operates at a high speed, and control unloading.

In the present embodiment, the functional valve sheet includes two relief valve sheets 139 and a main valve sheet 135 disposed between the two relief valve sheets 139, wherein the two relief valve sheets 139 are a first relief valve sheet 133 and a second relief valve sheet 136, respectively, and the thickness of the main valve sheet 135 is greater than the thickness of the first thin valve sheet 131 and the thickness of the second thin valve sheet 132. The first thin valve plate 131, the first relief valve plate 133, the main valve plate 135, the second relief valve plate 136, and the second thin valve plate 132 are sequentially disposed in a direction from the valve stopper 120 to the piston body 140. The first relief valve plate 133 and the second relief valve plate 136 respectively perform a relief function in the extension stroke and the compression stroke of the piston assembly 100.

Optionally, the number of the main valve plates 135 is multiple, in this embodiment, the number of the main valve plates 135 is three, and the thicknesses of the three main valve plates 135 are the same. It is understood that in other embodiments, the number and thickness of the main valve plate 135 may be specifically determined according to the required damping force.

It should be noted that specific composition of the functional valve sheet is not limited herein, and it can be understood that, in other embodiments, the order or number of the valve sheets included in the functional valve sheet may also be set according to the required damping force, for example, the main valve sheets 135 are set to be two, the unloading valve sheet 139 is disposed between the two main valve sheets 135, that is, the two main valve sheets 135 are the first main valve sheet and the second main valve sheet respectively, so along the direction from the valve stop 120 to the piston body 140, the first thin valve sheet 131, the first main valve sheet, the unloading valve sheet 139, the second main valve sheet and the second thin valve sheet 132 are sequentially disposed, meanwhile, the thickness of the first main valve sheet is greater than the thickness of the first thin valve sheet 131 and the thickness of the second thin valve sheet 132, and the thickness of the second main valve sheet is greater than the thickness of the first thin valve sheet 131 and the thickness of the second thin valve sheet 132; alternatively, the functional valve plate is set to include only one valve plate (for example, the required damping force is sufficiently small), so that the speed-damping force variation requirement and the unloading function can be met at the same time.

It should be noted that, in the description of the present embodiment, the thin valve sheet refers to a valve sheet with a thickness smaller than the overall thickness of the functional valve sheet, and in the case that the functional valve sheet includes the independent main valve sheet 135 and the relief valve sheet 139, the thickness of the thin valve sheet is smaller than the thickness of any one main valve sheet 135.

Fig. 4 is a schematic structural diagram of the first relief valve plate 133 in the piston assembly 100 provided in this embodiment, and fig. 5 is a schematic structural diagram of the second relief valve plate 136 in the piston assembly 100 provided in this embodiment. Referring to fig. 1 to fig. 5, in the present embodiment, a throttle slot 138 is disposed on the unloading valve plate 139, and the throttle slot 138 forms an opening on an inner edge or an outer edge of the unloading valve plate 139.

Specifically, the throttle groove 138 on the first relief valve plate 133 is a first throttle groove 134, and the first throttle groove 134 penetrates through the inner edge of the first relief valve plate 133 to form an opening, that is, the first throttle groove 134 is communicated with the inner peripheral space of the first relief valve plate 133. The throttle groove 138 on the second relief valve plate 136 is a second throttle groove 137, and the second throttle groove 137 penetrates through the outer edge of the second relief valve plate 136 to form an opening, that is, the second throttle groove 137 is communicated with the outer peripheral space of the second relief valve plate 136. Alternatively, the number of the throttle grooves 138 on the relief valve plate 139 is plural, and the plural throttle grooves 138 are uniformly distributed along the circumferential direction of the relief valve plate 139. It is understood that in other embodiments, the number of the throttle grooves 138 can be specifically set according to the magnitude of the damping force, and even the number of the throttle grooves 138 can be set to zero, so that the relief valve plate 139 is a ring shape having approximately the same shape as the thin valve plate and the main valve plate 135.

It should be noted that, in this embodiment, the penetration directions of the throttling grooves 138 in the first unloading valve plate 133 and the second unloading valve plate 136 are different, and it can be understood that, in other embodiments, the throttling grooves may be specifically arranged according to a required damping force, for example, the first unloading valve plate 133 and the second unloading valve plate 136 are both arranged in the structure shown in fig. 4, or the first unloading valve plate 133 and the second unloading valve plate 136 are both arranged in the structure shown in fig. 5.

Fig. 6 is a schematic structural view of the valve stop 120 in the piston assembly 100 according to the present embodiment at a first viewing angle, and fig. 7 is a schematic structural view of the valve stop 120 in the piston assembly 100 according to the present embodiment at a second viewing angle. Referring to fig. 2, 3, 6 and 7, in the present embodiment, the valve stop 120 is provided with a first flow channel 121, an inner circumference of the damping valve set 130 forms a throttling gap 162, and a communication gap 161 for communicating the first flow channel 121 and the throttling gap 162 is formed between the first thin valve plate 131 and the valve stop 120. The piston body 140 defines a second flow path 141, and the first flow path 121, the communication gap 161, the throttle gap 162 and the second flow path 141 are sequentially communicated to form a passage 160 for hydraulic oil to flow, such that hydraulic oil enters and exits the first chamber 212 and the second chamber 213 through the passage 160 during the movement of the piston assembly 100.

Specifically, the first flow passage 121 is a plurality of through holes opened in the valve stop 120, and the through holes extend in the axial direction of the valve stop 120. The projection of the first flow channel 121 on the plane of the first thin valve plate 131 along the axial direction is located at the first thin valve plate 131, that is, the hydraulic oil flowing to the first thin valve plate 131 along the first flow channel 121 acts on the first thin valve plate 131, so that the first thin valve plate 131 deforms when the piston assembly 100 moves at a low speed in the extension stroke.

The end face of the valve stopper 120 close to the first thin valve plate 131 is provided with a protrusion 122, the protrusion 122 abuts against the first thin valve plate 131, so that the end face of the valve stopper 120 is supported away from the first thin valve plate 131, and a communication gap 161 communicating with the first flow channel 121 can be formed between the first thin valve plate 131 and the end face of the valve stopper 120.

Meanwhile, the first thin valve plate 131, the first unloading valve plate 133, the main valve plate 135, the second unloading valve plate 136 and the second thin valve plate 132 are coaxially arranged, and the inner holes have the same size, in order to ensure the consistency of the sizes of the inner holes of the first thin valve plate 131, the first unloading valve plate 133, the main valve plate 135, the second unloading valve plate 136 and the second thin valve plate 132 in actual production, the first thin valve plate 131, the first unloading valve plate 133, the main valve plate 135, the second unloading valve plate 136 and the second thin valve plate 132 can be firstly laminated together, and then the inner holes are processed.

Further, the piston assembly 100 further includes a supporting block 163 sleeved on the connecting section 112, and an inner diameter of the damping valve set 130 is greater than an outer diameter of the supporting block 163, so that after the damping valve set 130 is sleeved on the connecting section 112, the damping valve set 130 is located at a radial outer side of the supporting block 163, and a throttling gap 162 is formed between an inner circumference of the damping valve set 130 and an outer circumference of the supporting block 163, thereby facilitating communication between the throttling gap 162 extending along the axial direction of the piston assembly 100 and the second flow passage 141. It will be appreciated that in other embodiments, the throttle gap 162 may be provided directly through the damper block assembly 130 and the connecting section 112.

The second flow passage 141 is a through-hole that penetrates the piston body 140 in the axial direction of the piston body 140. Alternatively, the through hole forming the second flow passage 141 includes a small-diameter section 142 and large-diameter sections 143 provided at both ends of the small-diameter section 142, i.e., the cross-sectional shape of the second flow passage 141 is dumbbell-shaped as shown in fig. 1. Through the shape of the second flow passage 141, on one hand, the communication between the throttle gap 162 and the second flow passage 141 is facilitated on the basis of ensuring the rigidity of the piston body 140, and on the other hand, the weight of the piston body 140 can be effectively reduced.

Fig. 8 is an enlarged view of a portion of the structure at viii in fig. 2. Referring to fig. 2 and 8, in the present embodiment, the piston assembly 100 further includes a sealing assembly 150, a sealing groove 144 is formed on an outer periphery of the piston body 140, and the sealing assembly 150 is installed in the sealing groove 144, and guides and seals the movement of the piston body 140 at a high pressure through the sealing assembly 150, so as to ensure the sealing performance of the first chamber 212 and the second chamber 213 on the outer periphery of the piston body 140.

Optionally, the sealing assembly 150 includes an O-ring 151 and a quad ring 152, the sealing groove 144 includes a first groove 145 for mounting the quad ring 152 and a second groove 146 for mounting the O-ring 151, and the second groove 146 is opened at the bottom of the first groove 145, and the high pressure sealing is realized by the cooperation of the quad ring 152 and the O-ring 151. Meanwhile, since the width of the quad ring 152 is greater than that of the O-ring 151, and thus the width of the corresponding first groove portion 145 is greater than that of the second groove portion 146, the quad ring 152 performs a function of guiding the movement of the piston body 140.

Through the arrangement of the sealing assembly 150, the length of the piston body 140 can meet the width requirement of the first groove portion 145, which helps to shorten the length of the piston body 140, and further shortens the length of the piston assembly 100, so as to meet the requirement of the limited working condition of the rail vehicle.

According to the piston assembly 100 provided in the present embodiment, the working principle of the piston assembly 100 is as follows:

in the piston assembly 100 of the present embodiment, during the extension stroke, the volume of the first chamber 212 decreases, and the volume of the second chamber 213 increases, so that the hydraulic oil in the first chamber 212 tends to flow toward the second chamber 213 through the passage 160 (the arrow shown in fig. 3 is the flow direction of the hydraulic oil). Specifically, when the piston assembly 100 moves at a low speed, the hydraulic oil in the first chamber 212 flows to the second chamber 213 through the throttle groove 138 and the throttle gap 162, and generates a damping force at the low speed through the damping valve set 130, and as the moving speed of the piston assembly 100 increases, the hydraulic oil will sequentially open the first unloading valve piece 133 and the main valve piece 135, so that the damping force control of the piston assembly 100 in the extension stroke is realized. Obviously, the principle of the piston assembly 100 during the compression stroke is reversed from the above-described process, and will not be described in detail here.

The present embodiment provides a piston assembly 100 having at least the following advantages:

according to the piston assembly 100 provided by the embodiment of the invention, by arranging the damping valve banks 130, one damping valve bank 130 can meet the damping force requirements in the stretching stroke and the compression stroke, the length of the piston assembly 100 is greatly reduced, the dead stroke of the rail vehicle oil pressure shock absorber 10 is further reduced, the working stroke of the rail vehicle oil pressure shock absorber 10 is improved, and the requirement of the rail vehicle on the limit working condition can be met. In addition, during production, only one damping valve bank 130 needs to be debugged to meet the requirements of tensile and compressive damping forces, and the assembly and debugging efficiency is greatly improved. The piston body 140 has a simple structural design, a small processing difficulty and a low manufacturing cost.

The present embodiment also provides a railway vehicle oil damper 10 that includes the piston assembly 100 described above, and thus also has all of the benefits of the piston assembly 100.

The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.