Low-temperature-resistant damping piston assembly

Abstract

The low-temperature-resistant damping piston assembly comprises a piston body, a plurality of damping oil channels are formed in the piston body, the damping oil channels penetrate through the two ends of the piston body, a first valve plate assembly and a second valve plate assembly which are matched with the damping oil channels are further arranged at the two ends of the piston body, and an annular groove is formed in the outer wall of the piston body. An O-shaped ring and a polytetrafluoroethylene piston ring are arranged in the ring groove, the O-shaped ring is arranged on the outer wall of the ring groove in a sleeving mode and matched with the ring groove in the radial direction in an abutting mode, the polytetrafluoroethylene piston ring is arranged on the outer wall of the O-shaped ring in a sleeving mode and matched with the O-shaped ring in the radial direction in an abutting mode, and the O-shaped ring has elasticity so that the polytetrafluoroethylene piston ring can have the movement tendency of expanding outwards in the radial direction. According to the technical scheme, the gap between the piston body and the cylinder barrel can be enlarged, the clamping stagnation phenomenon in the low-temperature environment is reduced, the abrasion resistance of the polytetrafluoroethylene piston ring can be improved, the polytetrafluoroethylene material has the high rigidity characteristic and is not prone to deformation, and the force value change caused by the thermal expansion and cold contraction phenomenon is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to piston assembly technical field, especially a low temperature resistant damping piston assembly. BACKGROUND

[0002] Damping piston is the common spare part in hydraulic buffer cylinder, damper and valve body, damping piston is usually movably arranged in cylinder barrel, damping piston is usually provided with damping hole, liquid generates damping through damping hole, but the conventional damping piston on the market performs poorly in low temperature resistance, specifically, if the fit clearance between the damping piston of conventional structure and cylinder barrel is designed too small, then in low temperature environment, for example in the environment of minus 40 DEG C, the damping piston and cylinder barrel shrink due to thermal expansion and contraction, if the fit clearance is originally small, then the actual clearance may become smaller due to shrinkage of both at low temperature, in this case, the friction force to be overcome by piston movement will greatly increase, especially at low speed, for example at the movement speed of 1mm / S, greater force is needed to push the piston to move, resulting in that the force value is too high and exceeds the preset force value range, but if the fit clearance between the damping piston and cylinder barrel is designed too large in order to prevent the jamming phenomenon in low temperature environment, then in normal temperature environment, liquid will more easily leak through the clearance, resulting in that the effective damping force is reduced, so that the actual force value is too low to meet the expected requirement, therefore, it is necessary to improve. SUMMARY

[0003] The utility model discloses to the defects and insufficiency of prior art, provide a low temperature resistant damping piston assembly, simple and reasonable structure, convenient operation, install rubber O type ring and polytetrafluoroethylene piston ring in annular groove, and O type ring has the elastic force and makes polytetrafluoroethylene piston ring have the movement tendency of expanding along the radial direction outward, to fill the clearance between cylinder barrel and piston body, so that the clearance between piston body and cylinder barrel can be enlarged, to reduce the jamming phenomenon in low temperature environment, install polytetrafluoroethylene piston ring on the outside of O type ring, can improve the wear resistance, and polytetrafluoroethylene material has high stiffness characteristics and is not easy to deform, to reduce the force value change due to thermal expansion and contraction.

[0004] To achieve the above object, the utility model adopts the following technical scheme:

[0005] The utility model discloses a low temperature resistant damping piston assembly, including piston body, be provided with a plurality of damping oil channel in the piston body, the damping oil channel penetrates the both ends of piston body, and the both ends of piston body still are provided with the first valve piece subassembly and the second valve piece subassembly who cooperates with the damping oil channel, the outer wall of piston body is provided with ring groove, be provided with O ring and polytetrafluoroethylene piston ring in the ring groove, the O ring is set in the outer wall of ring groove and with the radial abutment cooperation of ring groove, the polytetrafluoroethylene piston ring is set in the outer wall of O ring and with the radial abutment cooperation of O ring, the O ring has the elastic force to make the polytetrafluoroethylene piston ring have the movement tendency of radial outward expansion.

[0006] Further, the damping oil channel includes an oil hole provided in the piston body and a first shallow groove provided on an end surface of the piston body, a first deep groove in communication with the first shallow groove, a second shallow groove, and a second deep groove in communication with the second shallow groove. The first shallow groove and the second deep groove are arranged close to the outer edge of the piston body, and the first deep groove and the second shallow groove are arranged close to the center of the piston body. The oil hole penetrates the both ends of the piston body in the axial direction, and the both ends of the oil hole are provided with an oil inlet and an oil outlet, respectively. The oil inlet is in communication with the first deep groove, and the oil outlet is in communication with the second shallow groove.

[0007] Further, the piston body is provided with a through hole at the center thereof. The first deep groove is arranged between the first shallow groove and the through hole, and the second shallow groove is arranged between the second deep groove and the through hole.

[0008] Further, the oil inlets of part of the oil holes and the oil outlets of the remaining part of the oil holes are alternately arranged on the same end surface of the piston body in the circumferential direction. The second deep groove is in sealing cooperation with the first valve piece assembly or the second valve piece assembly, and a gap is formed between the first shallow groove and the first valve piece assembly or the second valve piece assembly.

[0009] Further, the first valve piece assembly includes a plurality of first valve piece bodies. The first valve piece bodies are sequentially arranged on the upper end surface of the piston body in the axial direction, and the adjacent two first valve piece bodies are in abutting cooperation in the axial direction.

[0010] Further, the second valve piece assembly includes a plurality of second valve piece bodies. The second valve piece bodies are sequentially arranged on the lower end surface of the piston body in the axial direction, and the adjacent two second valve piece bodies are in abutting cooperation in the axial direction.

[0011] Further, the upper end surface of the first valve piece assembly is provided with a first gasket, and a first spacer is further arranged between the first gasket and the first valve piece assembly.

[0012] Further, the lower end surface of the second valve piece assembly is provided with a second gasket, and a second spacer is further arranged between the second gasket and the second valve piece assembly.

[0013] Further, the cross section of the polytetrafluoroethylene piston ring is rectangular.

[0014] Further, the O-ring is made of rubber material.

[0015] The utility model discloses a low temperature resistant damping piston assembly, can effectively play the role of sealing, the polytetrafluoroethylene piston ring is sleeved in the outer wall of O -ring and is along the radial with O -ring and is matched, effectively plays the role of sealing, and O -ring is made of rubber material, and rubber material has good elasticity and durability, and O -ring has the elastic force and makes the polytetrafluoroethylene piston ring have the movement tendency of expanding along the radial outward, to fill the gap between cylinder and piston body, make the gap between piston body and cylinder can be enlarged, to reduce the jam phenomenon under low temperature environment, through the polytetrafluoroethylene piston ring of installing outside O -ring, can significantly improve the wear resistance, and then prolong its service life, in addition, polytetrafluoroethylene material has high stiffness characteristics, and is not easy to deform, can effectively reduce the force value change caused by deformation, thereby reducing the abnormal big force value caused by thermal expansion and cold shrinkage under low temperature, not only this, the polytetrafluoroethylene piston ring of installing outside O -ring can also effectively reduce static friction, and the conventional O -ring directly contacts with the inner wall of cylinder, mainly relies on the elasticity and compression of rubber to form sealing, but rubber material can produce greater resistance when starting the piston, and the polytetrafluoroethylene piston ring has lower friction coefficient compared with O -ring, can effectively reduce the resistance when starting the piston. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is the overall structure schematic diagram of the utility model;

[0017] Figure 2 It is the exploded structure schematic diagram of the utility model;

[0018] Figure 3 It is the cross section structure schematic diagram of the utility model;

[0019] Figure 4 It is the cross section structure schematic diagram of the piston body;

[0020] Figure 5 It is the structure schematic diagram of the piston body.

[0021] Figures 1-5Middle: 1, piston body; 11, through hole; 12, ring groove; 121, O-ring; 122, polytetrafluoroethylene piston ring; 2, damping oil channel; 21, oil hole; 211, oil inlet; 212, oil outlet; 22, first shallow groove; 23, first deep groove; 231, inclined surface; 24, second shallow groove; 25, second deep groove; 3, first valve piece assembly; 31, first valve piece body; 4, second valve piece assembly; 41, second valve piece body; 5, first gasket; 6, first spacer; 7, second gasket; 8, second spacer. DETAILED DESCRIPTION

[0022] The utility model will be further described below with reference to the drawings.

[0023] As Figures 1-5 The low-temperature-resistant damping piston assembly shown in the figure comprises a piston body 1, the piston body 1 is movably arranged in a cylinder, a plurality of damping oil channels 2 are arranged in the piston body 1, the damping oil channels 2 pass through both ends of the piston body 1, liquid generates damping through the damping oil channels 2, and the two ends of the piston body 1 are respectively provided with a first valve piece assembly 3 and a second valve piece assembly 4 matched with the damping oil channels 2, an outer wall of the piston body 1 is provided with a ring groove 12, and the ring groove 12 is provided with an O-ring 121 and a polytetrafluoroethylene piston ring 122, preferably, in the embodiment, referring to Figure 3The cross section of the polytetrafluoroethylene piston ring 122 is rectangularly arranged, which is not easy to be separated from the ring groove 12. The O-ring 121 is sleeved on the outer wall of the ring groove 12 and is in abutting engagement with the ring groove 12 in the radial direction, which can effectively play a sealing role. The polytetrafluoroethylene piston ring 122 is sleeved on the outer wall of the O-ring 121 and is in abutting engagement with the O-ring 121 in the radial direction, which effectively plays a sealing role. Preferably, in the embodiment, the O-ring 121 is made of rubber material, which has good elasticity and durability. The O-ring 121 has elasticity, so that the polytetrafluoroethylene piston ring 122 has a movement trend of expanding outward in the radial direction, so as to fill the gap between the cylinder and the piston body 1. The gap between the piston body 1 and the cylinder can be increased, so as to reduce the jamming phenomenon in the low temperature environment. By installing the polytetrafluoroethylene piston ring 122 outside the O-ring 121, the wear resistance can be significantly improved, and the service life can be prolonged. In addition, the polytetrafluoroethylene material has high stiffness characteristics and is not easy to deform, which can effectively reduce the force value change caused by deformation, thereby reducing the abnormally large force value caused by thermal expansion and cold shrinkage in low temperature. Moreover, the installation of the polytetrafluoroethylene piston ring 122 outside the O-ring 121 can effectively reduce the static friction. The conventional O-ring 121 directly contacts the inner wall of the cylinder, mainly relying on the elasticity and compression of the rubber to form a seal. However, the rubber material will generate a large resistance when the piston starts. The polytetrafluoroethylene piston ring 122 has a lower friction coefficient than the O-ring 121, which can effectively reduce the resistance when the piston starts.

[0024] Preferably, in the embodiment, referring to Figure 4, the damping oil channel 2 comprises an oil hole 21 arranged in the piston body 1, a first shallow groove 22 arranged on the end face of the piston body 1, a first deep groove 23 communicated with the first shallow groove 22, a second shallow groove 24, and a second deep groove 25 communicated with the second shallow groove 24, and a slope 231 for transition is arranged between the first shallow groove 22 and the first deep groove 23, so as to facilitate the oil to flow into the first deep groove 23 from the first shallow groove 22, in the embodiment, the ring groove 12 is designed to be deep to install the O-ring 121 and the polytetrafluoroethylene piston ring 122, in order to prevent the oil hole 21 from interfering with the ring groove 12, in the embodiment, the position of the oil hole 21 is adjusted to the center direction of the piston, the first deep groove 23 and the second shallow groove 24 are arranged close to the center of the piston body 1, preferably, in the embodiment, a through hole 11 is arranged in the center of the piston body 1, the first deep groove 23 is arranged between the first shallow groove 22 and the through hole 11, the second shallow groove 24 is arranged between the second deep groove 25 and the through hole 11, the oil hole 21 penetrates through both ends of the piston body 1 in the axial direction, the oil inlet 211 and the oil outlet 212 are arranged at both ends of the oil hole 21 respectively, the oil inlet 211 is communicated with the first deep groove 23, the oil outlet 212 is communicated with the second shallow groove 24, and the first shallow groove 22 and the second deep groove 25 are arranged close to the outer edge of the piston body 1.

[0025] Preferably, in the embodiment, referring to Figure 5 , the oil inlets 211 of part of the oil holes 21 and the oil outlets 212 of the remaining part of the oil holes 21 are alternately arranged on the same end face of the piston body 1 in the circumferential direction, in the embodiment, the oil hole 21 is provided with six oil holes, three oil inlets 211 of the oil holes 21 are arranged on the upper end face of the piston body 1, and the remaining three oil inlets 211 of the oil holes 21 are arranged on the lower end face of the piston body 1, which enables the oil to flow in both directions inside the piston body 1, and the alternately arranged oil inlets 211 and oil outlets 212 in the circumferential direction can ensure that the oil can flow into and out of the piston body 1 uniformly, the second deep groove 25 on the upper end face of the piston body 1 is in sealing cooperation with the first valve plate assembly 3, and the second deep groove 25 on the lower end face of the piston body 1 is in sealing cooperation with the second valve plate assembly 4, specifically, the first shallow groove 22 is open to the outside of the piston body 1, a gap is formed between the first shallow groove 22 on the upper end face of the piston body 1 and the first valve plate assembly 3, and a gap is formed between the first shallow groove 22 on the lower end face of the piston body 1 and the second valve plate assembly 4, the oil enters the first shallow groove 22 through the gap, and then flows through the first deep groove 23, the oil inlet 211, the oil hole 21, the oil outlet 212, the second shallow groove 24 and the second deep groove 25 in sequence.

[0026] Specifically, the oil liquid first flows into the first deep groove 23 through the first shallow groove 22, and then flows into the oil hole 21 through the oil inlet 211. After the oil liquid flows out from the oil outlet 212, it first flows into the second shallow groove 24, and then further flows into the second deep groove 25. The oil liquid in the second deep groove 25 exerts a force on the first valve plate assembly 3 or the second valve plate assembly 4 to push it open to make the oil liquid flow out. Since the second deep groove 25 is arranged at a position close to the outer edge of the piston body 1, the pushing force required for the oil liquid to push the first valve plate assembly 3 or the second valve plate assembly 4 is small, and the first valve plate assembly 3 or the second valve plate assembly 4 can be more easily pushed open, thereby ensuring that the oil liquid can push the first valve plate assembly 3 or the second valve plate assembly 4 open at low speed, and improving the response speed between the speed and the force value. In order to avoid interference between the oil hole 21 and the ring groove 12, the oil hole 21 can be arranged close to the center of the piston body 1. In addition, at high speed, the oil liquid sequentially passes through the first shallow groove 22, the first deep groove 23, the oil hole 21, the second shallow groove 24, and the second deep groove 25, which effectively plays a buffering role and can avoid the deformation of the first valve plate assembly 3 or the second valve plate assembly 4 caused by the rapid impact of the oil liquid.

[0027] Preferably, in the embodiment, referring to Figure 2 , the first valve plate assembly 3 comprises a plurality of first valve plate bodies 31, which are arranged in sequence along the axial direction on the upper end surface of the piston body 1, and the adjacent two first valve plate bodies 31 are in abutting fit along the axial direction, with good sealing effect.

[0028] Preferably, in the embodiment, referring to Figure 2 , the second valve plate assembly 4 comprises a plurality of second valve plate bodies 41, which are arranged in sequence along the axial direction on the lower end surface of the piston body 1, and the adjacent two second valve plate bodies 41 are in abutting fit along the axial direction, with good sealing effect.

[0029] Preferably, in the embodiment, referring to Figure 2 , the upper end surface of the first valve plate assembly 3 is provided with a first gasket 5, which plays a buffering role. A first partition plate 6 is further arranged between the first gasket 5 and the first valve plate assembly 3 to avoid direct contact therebetween, thereby reducing the wear between the first gasket 5 and the first valve plate assembly 3.

[0030] Preferably, in the embodiment, referring to Figure 2 , the lower end surface of the second valve plate assembly 4 is provided with a second gasket 7, which plays a buffering role. A second partition plate 8 is further arranged between the second gasket 7 and the second valve plate assembly 4 to avoid direct contact therebetween, thereby reducing the wear between the second gasket 7 and the second valve plate assembly 4.

[0031] The above merely describes preferred embodiments of the present application, and thus equivalent changes or modifications made in accordance with the structure, features and principles described in the patent application scope of the present application are included in the patent application scope of the present application.

Claims

1. A low-temperature-resistant damping piston assembly, comprising a piston body (1), a plurality of damping oil channels (2) are arranged in the piston body (1), the damping oil channels (2) pass through both ends of the piston body (1), and a first valve plate assembly (3) and a second valve plate assembly (4) matched with the damping oil channels (2) are arranged at both ends of the piston body (1) respectively, and an annular groove (12) is arranged on the outer wall of the piston body (1), characterized in that: An O-ring (121) and a polytetrafluoroethylene piston ring (122) are arranged in the annular groove (12), the O-ring (121) is sleeved on the outer wall of the annular groove (12) and is in abutting fit with the annular groove (12) in the radial direction, the polytetrafluoroethylene piston ring (122) is sleeved on the outer wall of the O-ring (121) and is in abutting fit with the O-ring (121) in the radial direction, and the O-ring (121) has elastic force so that the polytetrafluoroethylene piston ring (122) has a movement tendency of expanding outward in the radial direction. ​ 2. The low temperature resistant damped piston assembly of claim 1, wherein: The damping oil channel (2) comprises an oil hole (21) arranged in the piston body (1), a first shallow groove (22) arranged on the end face of the piston body (1), a first deep groove (23) in communication with the first shallow groove (22), a second shallow groove (24), and a second deep groove (25) in communication with the second shallow groove (24), the first shallow groove (22) and the second deep groove (25) are arranged close to the outer edge of the piston body (1), the first deep groove (23) and the second shallow groove (24) are arranged close to the center of the piston body (1), the oil hole (21) penetrates through both ends of the piston body (1) in the axial direction, and the two ends of the oil hole (21) are respectively provided with an oil inlet (211) and an oil outlet (212), the oil inlet (211) is in communication with the first deep groove (23), and the oil outlet (212) is in communication with the second shallow groove (24).

3. A low temperature resistant damped piston assembly as claimed in claim 2, wherein: The piston body (1) is provided with a through hole (11) at the center, the first deep groove (23) is arranged between the first shallow groove (22) and the through hole (11), and the second shallow groove (24) is arranged between the second deep groove (25) and the through hole (11).

4. The low temperature resistant damped piston assembly of claim 2, wherein: The oil inlets (211) of part of the oil holes (21) and the oil outlets (212) of the remaining part of the oil holes (21) are alternately arranged on the same end face of the piston body (1) in the circumferential direction, the second deep groove (25) is in sealing fit with the first valve plate assembly (3) or the second valve plate assembly (4), and a gap is formed between the first shallow groove (22) and the first valve plate assembly (3) or the second valve plate assembly (4).

5. The low temperature resistant damped piston assembly of claim 1, wherein: The first valve plate assembly (3) comprises a plurality of first valve plate bodies (31), the plurality of first valve plate bodies (31) are arranged in sequence in the axial direction on the upper end face of the piston body (1), and adjacent two first valve plate bodies (31) are in abutting fit in the axial direction.

6. The low temperature resistant damped piston assembly of claim 1, wherein: The second valve plate assembly (4) comprises a plurality of second valve plate bodies (41), the plurality of second valve plate bodies (41) are arranged in sequence in the axial direction on the lower end face of the piston body (1), and adjacent two second valve plate bodies (41) are in abutting fit in the axial direction.

7. The low temperature resistant damped piston assembly of claim 1, wherein: The upper end face of the first valve plate assembly (3) is provided with a first gasket (5), and a first partition plate (6) is further arranged between the first gasket (5) and the first valve plate assembly (3).

8. The low temperature resistant damped piston assembly of claim 1, wherein: The lower end face of the second valve plate assembly (4) is provided with a second gasket (7), and a second partition plate (8) is further arranged between the second gasket (7) and the second valve plate assembly (4).

9. The low temperature resistant damped piston assembly of claim 1, wherein: The polytetrafluoroethylene piston ring (122) is rectangular in cross section.

10. The low temperature resistant damped piston assembly of claim 1, wherein: The O-ring (121) is made of rubber material.

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