CN209761905U - Hydraulic cylinder with clearance dynamic sealing piston - Google Patents
Hydraulic cylinder with clearance dynamic sealing piston Download PDFInfo
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- CN209761905U CN209761905U CN201920323691.7U CN201920323691U CN209761905U CN 209761905 U CN209761905 U CN 209761905U CN 201920323691 U CN201920323691 U CN 201920323691U CN 209761905 U CN209761905 U CN 209761905U
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Abstract
The utility model discloses a hydraulic cylinder with a clearance dynamic sealing piston, which comprises a cylinder body, a piston rod, a guide sleeve and a cylinder cover; the piston is characterized in that a groove group is arranged on the outer circumferential surface of the piston along the circumferential direction of the piston, the groove group comprises a plurality of inwards-concave grooves uniformly distributed along the circumferential direction, each inwards-concave groove comprises an oil groove and a V-shaped conical surface, the oil grooves are positioned in the middle of the inwards-concave grooves, the length directions of the oil grooves are arranged along the circumferential direction of the piston, the V-shaped conical surfaces are front conical surfaces and rear conical surfaces which are symmetrically arranged front and back relative to the oil grooves, the top ends of the front conical surfaces and the rear conical surfaces are respectively connected with the outer circumferential surface of the piston, the bottom ends of the front conical surfaces and the bottom ends of the rear conical surfaces are respectively connected with the top ends of the walls of the oil grooves, the top ends of the front conical. The utility model discloses can guarantee the liquid lubrication between piston and the cylinder body, effectively reduce the piston in the prerequisite of leaking under avoid the piston card dead and draw the jar phenomenon.
Description
Technical Field
The utility model relates to a pneumatic cylinder specifically is a pneumatic cylinder with clearance movive seal piston, belongs to hydraulic cylinder technical field.
Background
The hydraulic cylinder is a hydraulic actuator which converts hydraulic energy into mechanical energy and makes linear reciprocating motion (or swinging motion), and is widely applied to hydraulic systems of various machines.
The pneumatic cylinder includes cylinder, cylinder cap, piston rod and sealing device usually, and sealed the adoption between the piston of traditional pneumatic cylinder and the cylinder is generally set up the sealing washer mounting groove on piston circumference direction and is installed the rubber material sealing washer realization in the sealing washer mounting groove with the cooperation, but the seal structure of this kind of traditional form easily produces the phenomenon of crawling when the low speed, will cause sealing washer life's shortening when high-speed again. Therefore, in the high-end products of the hydraulic cylinder, the piston sealing mode mostly adopts a constant clearance sealing mode, for example, a clearance piston sealing hydraulic cylinder disclosed in chinese patent ZL200820204905.0 is provided with a certain number of circumferentially through annular pressure equalizing grooves on the circumferential surface of the piston, the annular pressure equalizing grooves form a clearance sealing strip between the piston and the cylinder body, and a complete fluid lubrication state is formed between the piston and the cylinder body. In order to solve the problem of pressure loss of a dynamic pressure oil film, a hydraulic cylinder with an adjustable piston gap appears in the prior art, for example, a deformed piston gap sealed hydraulic cylinder disclosed in chinese patent ZL200910272743.3, in which 3 to 5 equalizing grooves are arranged on the outer circle of a piston, and annular boss lips having the same outer diameter as the piston are arranged on both end faces of the piston.
Disclosure of Invention
To the problem that above-mentioned prior art exists, the utility model provides a pneumatic cylinder with clearance dynamic seal piston can realize avoiding the piston card to die and draw the jar phenomenon under the prerequisite of guaranteeing the liquid lubrication between piston and the cylinder body, effectively reducing the piston internal leakage.
In order to achieve the purpose, the hydraulic cylinder with the clearance dynamic sealing piston comprises a cylinder body, a piston rod, a guide sleeve and a cylinder cover; the cylinder body is of a barrel-shaped structure with an open end, the outer diameter size of the piston is in clearance fit with the inner diameter size of the cylinder body, the piston and the piston rod are coaxially arranged and installed inside the cylinder body, the guide sleeve and the cylinder cover are sequentially installed at the position of a cylinder opening of the cylinder body from inside to outside, the piston rod penetrates through the guide sleeve and the cylinder cover and extends out of the cylinder body, annular sealing components are arranged between the cylinder cover and the cylinder body and between the cylinder cover and the piston rod, the piston divides an inner cavity of the cylinder body into a rod cavity and a rodless cavity, and oil injection ports or oil drainage ports are respectively arranged at positions on the cylinder body;
The piston is characterized in that a groove group is arranged on the outer circumferential surface of the piston along the circumferential direction of the piston, the groove group comprises a plurality of inward-concave grooves which are uniformly distributed along the circumferential direction, the inward-concave grooves are of a front-back symmetrical structure and comprise oil grooves and V-shaped conical surfaces, the oil grooves are positioned in the middle of the front-back direction of the inward-concave grooves, the length directions of the oil grooves are arranged along the circumferential direction of the piston, the V-shaped conical surfaces are symmetrically arranged front and back relative to the oil grooves and comprise front conical surfaces and back conical surfaces, the front conical surfaces and the back conical surfaces jointly form the V-shaped structure, the top ends of the front conical surfaces and the back conical surfaces are respectively connected with the outer circumferential surface of the piston, the bottom ends of the front conical surfaces and the back conical surfaces are respectively connected with the top ends of the groove walls of the oil grooves.
As an embodiment of the present invention, the length dimension of the oil groove in the circumferential direction of the outer circumferential surface of the piston is the same as the width dimension of the V-shaped conical surface in the circumferential direction of the outer circumferential surface of the piston.
As another embodiment of the present invention, the length dimension of the oil groove in the circumferential direction of the outer circumferential surface of the piston is greater than the width dimension of the V-shaped conical surface in the circumferential direction of the outer circumferential surface of the piston.
As another embodiment of the present invention, the length dimension of the oil groove in the circumferential direction of the outer circumferential surface of the piston is smaller than the width dimension of the V-shaped conical surface in the circumferential direction of the outer circumferential surface of the piston.
As a further improvement of the utility model, the front conical surface and the rear conical surface are arc conical surface structures which are arranged along the circumferential direction of the piston and have the same curvature.
As a further improvement of the utility model, the groove group is arranged into a plurality of groups along the axial direction of the piston.
As a further improvement of the utility model, the indent grooves of two adjacent groove sets are staggered in the axial direction of the piston.
as the utility model discloses a further improvement scheme, the position that corresponds the piston rod on the cylinder cap is equipped with the oil impregnate recovery ring channel, and the oil impregnate recovery ring channel is located the inboard of the annular seal subassembly between cylinder cap and the piston rod, still is equipped with the oil impregnate recovery passageway that sets up along its radial direction on the cylinder cap, and oil impregnate recovery passageway and the setting of oil impregnate recovery ring channel intercommunication.
Compared with the prior art, the piston and the cylinder body of the hydraulic cylinder with the clearance dynamic sealing piston can automatically keep concentric under the action of fluid pressure, so that the clearance of a slit between the outer circumferential surface of the piston and the inner cavity wall of the cylinder body can be kept constant, the throttling effect of the clearance of the slit can realize the retarding effect on fluid, and meanwhile, when the hydraulic cylinder is in a starting or stopping stage, the piston is in a mixed friction state, and the clearance of the slit can ensure that the piston is not subjected to aggravation of abrasion caused by overlarge pressure intensity of the piston during mixed friction; because the depth from the inner cavity wall of the cylinder body to the bottom of the oil groove is far larger than the gap of the slit, the fluid flowing into the oil groove forms turbulent flow, and the original fluid in the oil groove is subjected to the wall resistance and the flow resistance of the ledge under the action of the eddy current, so that the speed and the pressure of the fluid flowing into the oil groove are reduced, and the leakage of the fluid is reduced; in addition, the front conical surface and the rear conical surface of the V-shaped conical surface form wedge-shaped gaps with the inner cavity wall of the cylinder body, due to the hydrodynamic action of fluid, the front conical surface or the rear conical surface at the inlet side forms a convergent fluid wedge to generate high-pressure fluid to realize the retarding action of the fluid at the inlet, while the rear conical surface or the front conical surface at the outlet side forms a divergent fluid wedge to generate negative-pressure fluid to return the leaked fluid to the upstream, thereby realizing the pumping action of the upstream and reducing the leakage of the fluid at the downstream; the hydraulic cylinder with the clearance dynamic seal piston can avoid the phenomena of piston locking and cylinder pulling on the premise of ensuring liquid lubrication between the piston and the cylinder body and effectively reducing leakage in the piston.
Drawings
fig. 1 is a schematic structural diagram of the present invention;
FIG. 2 is an enlarged view of a portion of FIG. 1 from direction I;
Fig. 3 is a schematic structural diagram of the piston of the present invention;
3 fig. 3 4 3 is 3 a 3 sectional 3 view 3 a 3- 3 a 3 of 3 fig. 3 3 3. 3
In the figure: 1. the piston comprises a cylinder body, 2, a piston, 3, a piston rod, 4, a guide sleeve, 5, a cylinder cover, 6, an inward concave groove, 7, an oil groove, 8, a V-shaped conical surface, 81, a front conical surface, 82, a rear conical surface, 9 and a slit gap.
Detailed Description
The present invention will be further explained with reference to the drawings (hereinafter, the moving direction of the piston 2 will be described as the forward and backward direction).
as shown in fig. 1, the hydraulic cylinder with the clearance dynamic seal piston comprises a cylinder body 1, a piston 2, a piston rod 3, a guide sleeve 4 and a cylinder cover 5; the cylinder body 1 is a barrel-shaped structure with an open end, as shown in fig. 2, the outer diameter of the piston 2 is in clearance fit with the inner diameter of the cylinder body 1, a slit gap 9 is arranged between the outer circumferential surface of the piston 2 and the inner cavity wall of the cylinder body 1, the piston 2 and the piston rod 3 are coaxially arranged and installed inside the cylinder body 1, the guide sleeve 4 and the cylinder cover 5 are sequentially installed at the cylinder opening of the cylinder body 1 from inside to outside, the piston rod 3 penetrates through the guide sleeve 4 and the cylinder cover 5 and extends out of the cylinder body 1, annular sealing components are arranged between the cylinder cover 5 and the cylinder body 1 and between the cylinder cover 5 and the piston rod 3, the piston 2 divides the inner cavity of the cylinder body 1 into a rod cavity and a rodless cavity, and oil injection ports or oil drainage ports are respectively arranged at positions.
As shown in fig. 3 and 4, the outer circumferential surface of the piston 2 is provided with a groove group arranged along the circumferential direction, the groove group comprises a plurality of inner concave grooves 6 uniformly distributed along the circumferential direction, the inner concave grooves 6 are of a front-back symmetrical structure and comprise oil grooves 7 and V-shaped conical surfaces 8, the oil grooves 7 are positioned in the middle of the front-back direction of the inner concave grooves 6, the length direction of the oil grooves 7 is arranged along the circumferential direction of the piston 2, the V-shaped conical surfaces 8 are arranged front-back symmetrically relative to the oil grooves 7 and comprise front conical surfaces 81 and rear conical surfaces 82, the front conical surfaces 81 and the rear conical surfaces 82 jointly form a V-shaped structure, the top ends of the front conical surfaces 81 and the rear conical surfaces 82 are respectively connected with the outer circumferential surface of the piston 2, and the bottom ends of the, the tip of the front tapered surface 81 or the tip of the rear tapered surface 82 does not penetrate the front end surface of the piston 2, and the tip of the rear tapered surface 82 or the tip of the front tapered surface 81 does not penetrate the rear end surface of the piston 2.
When the hydraulic cylinder with the clearance dynamic seal piston is used, the front end and the rear end of the V-shaped conical surface 8 can be respectively defined as an inlet and an outlet of fluid according to the moving direction of the piston 2, when the piston 2 moves from the small end to the large end of the oil wedge, the inlet is formed, and otherwise, the outlet is formed. The front conical surface 81 and the rear conical surface 82 of the V-shaped conical surface 8 form a wedge-shaped gap with the inner cavity wall of the cylinder body 1. Due to the action of fluid dynamic pressure, the front conical surface 81 or the rear conical surface 82 on the inlet side forms a convergent fluid wedge to generate high-pressure fluid, so that the retardation effect of the inlet on the fluid is realized; due to the action of fluid dynamic pressure, the rear conical surface 82 or the front conical surface 81 on the outlet side forms a divergent fluid wedge to generate negative pressure fluid, the leaked fluid is returned to the upstream, the upstream pumping action is realized, the leakage of the downstream fluid is reduced, and meanwhile, the returned fluid has pressure and has a blocking action on the fluid flowing from the inlet side.
On one hand, under the action of fluid pressure, the piston 2 and the cylinder 1 can automatically keep concentric, so that a slit gap 9 between the outer circumferential surface of the piston 2 and the inner cavity wall of the cylinder 1 can be kept constant; on the other hand, because the depth from the inner cavity wall of the cylinder 1 to the bottom of the oil groove 7 is far larger than the size of the slit gap 9, the fluid flowing into the oil groove 7 forms turbulent flow, and the original fluid in the oil groove 7 is subjected to wall resistance and flow resistance of the ledge under the action of the turbulent flow, which is beneficial to reducing the speed and pressure of the fluid flowing into the oil groove 7, thereby reducing the leakage of the fluid.
A slit gap 9 is formed between adjacent concave grooves 6 in the circumferential direction of the outer circumferential surface of the piston 2, and the top end of the V-shaped conical surface 8 is not communicated with the front end surface and the rear end surface of the piston 2, so that a small and constant slit gap 9 can be formed between the outer circumferential surface of the piston 2 and the inner cavity wall of the cylinder body 1 in the moving process of the piston 2, the fluid can be retarded due to the throttling effect of the slit gap 9, meanwhile, the piston 2 is in a mixed friction state when the hydraulic cylinder is started or stopped, and the slit gap 9 can ensure that the abrasion of the piston 2 is not aggravated due to overlarge pressure of the piston 2 in the mixed friction process.
As an embodiment of the present invention, as shown in fig. 3, the length dimension of the oil groove 7 in the circumferential direction of the outer circumferential surface of the piston 2 is the same as the width dimension of the V-shaped tapered surface 8 in the circumferential direction of the outer circumferential surface of the piston 2. That is, the inner concave groove 6 has a rectangular structure when the inner concave groove 6 is viewed from above.
As another embodiment of the present invention, the length of the oil groove 7 in the circumferential direction of the outer circumferential surface of the piston 2 is greater than the width of the V-shaped tapered surface 8 in the circumferential direction of the outer circumferential surface of the piston 2. That is, the concave groove 6 has a spindle-shaped structure when the concave groove 6 is viewed from above.
As another embodiment of the present invention, the length of the oil groove 7 in the circumferential direction of the outer circumferential surface of the piston 2 is smaller than the width of the V-shaped tapered surface 8 in the circumferential direction of the outer circumferential surface of the piston 2. That is, the inner concave groove 6 has a bow-tie structure when the inner concave groove 6 is viewed from above.
In order to further reduce the leakage of the fluid, as a further improvement of the present invention, the front tapered surface 81 and the rear tapered surface 82 are arc-shaped tapered surface structures having the same curvature and arranged in the circumferential direction of the piston 2.
In order to further reduce the leakage of the fluid, as a further improvement of the present invention, the groove sets are arranged in plural sets in the front and rear direction of the axial direction of the piston 2.
In order to further reduce the leakage of the fluid, as a further improvement of the present invention, the concave grooves 6 of the two adjacent groove sets are alternately arranged in the axial direction of the piston 2.
In order to realize retrieving, avoiding the polluted environment hydraulic oil to oozing from the centre bore of cylinder cap 5, as the utility model discloses a further improvement scheme, the position that corresponds piston rod 3 on the cylinder cap 5 is equipped with the oil seepage and retrieves the ring channel, and the oil seepage is retrieved the ring channel and is located the inboard of the annular seal subassembly between cylinder cap 5 and the piston rod 3, still is equipped with the oil seepage recovery passageway that sets up along its radial direction on the cylinder cap 5, and oil seepage recovery passageway and the setting of oil seepage recovery ring channel intercommunication. In the working process of the hydraulic cylinder with the clearance dynamic seal piston, the oil seepage recovery channel can be connected with the hydraulic oil tank through the hose, and the hydraulic oil seeped out from the center hole of the cylinder cover 5 can flow back to the hydraulic oil tank through the oil seepage recovery channel, so that the environment pollution is avoided.
Claims (8)
1. A hydraulic cylinder with a clearance dynamic sealing piston comprises a cylinder body (1), a piston (2), a piston rod (3), a guide sleeve (4) and a cylinder cover (5); the cylinder body (1) is of a barrel-shaped structure with one open end, the outer diameter of the piston (2) is in clearance fit with the inner diameter of the cylinder body (1), the piston (2) and the piston rod (3) are coaxially arranged and installed inside the cylinder body (1), the guide sleeve (4) and the cylinder cover (5) are sequentially installed at the position of a cylinder opening of the cylinder body (1) from inside to outside, the piston rod (3) penetrates through the guide sleeve (4) and the cylinder cover (5) and extends out of the cylinder body (1), annular sealing assemblies are arranged between the cylinder cover (5) and the cylinder body (1) and between the cylinder cover (5) and the piston rod (3), the piston (2) divides an inner cavity of the cylinder body (1) into a rod cavity and a rodless cavity, and oil filling ports or oil draining ports are respectively arranged at positions corresponding to the rod cavity and the rodless cavity on the; it is characterized in that the preparation method is characterized in that,
The piston is characterized in that a groove group is arranged on the outer circumferential surface of the piston (2) along the circumferential direction of the piston, the groove group comprises a plurality of inward-concave grooves (6) uniformly distributed along the circumferential direction, the inward-concave grooves (6) are of a front-back symmetrical structure and comprise oil grooves (7) and V-shaped conical surfaces (8), the oil grooves (7) are positioned in the middle of the front-back direction of the inward-concave grooves (6), the length trend of the oil grooves (7) is arranged along the circumferential direction of the piston (2), the V-shaped conical surfaces (8) are symmetrically arranged front and back relative to the oil grooves (7) and comprise front conical surfaces (81) and rear conical surfaces (82), the front conical surfaces (81) and the rear conical surfaces (82) jointly form a V-shaped structure, the top ends of the front conical surfaces (81) and the rear conical surfaces (82) are respectively connected with the outer circumferential surface of the piston (2), the bottom ends of the front conical surfaces or the bottom ends of the rear conical surfaces (82) are respectively communicated with the top, The tip of the rear tapered surface (82) or the tip of the front tapered surface (81) does not penetrate the rear end surface of the piston (2).
2. The hydraulic cylinder with a gap-dynamic seal piston according to claim 1, wherein a length dimension of the oil groove in a circumferential direction of the outer circumferential surface of the piston is the same as a width dimension of the V-shaped tapered surface in the circumferential direction of the outer circumferential surface of the piston.
3. The hydraulic cylinder with a gap-dynamic sealing piston according to claim 1, wherein a length dimension of the oil groove (7) in a circumferential direction of the outer circumferential surface of the piston (2) is larger than a width dimension of the V-shaped tapered surface (8) in the circumferential direction of the outer circumferential surface of the piston (2).
4. The hydraulic cylinder with a gap-dynamic sealing piston according to claim 1, wherein a length dimension of the oil groove (7) in a circumferential direction of the outer circumferential surface of the piston (2) is smaller than a width dimension of the V-shaped tapered surface (8) in the circumferential direction of the outer circumferential surface of the piston (2).
5. the hydraulic cylinder with a gap-dynamic sealing piston according to any one of claims 1 to 4, wherein the front tapered surface (81) and the rear tapered surface (82) are arc-shaped tapered surface structures having the same curvature and arranged in the circumferential direction of the piston (2).
6. Hydraulic cylinder with gap-dynamic sealing piston according to any of claims 1 to 4, characterised in that the groove sets are arranged in groups one behind the other in the axial direction of the piston (2).
7. Hydraulic cylinder with gap-dynamic sealing piston according to claim 6, characterized in that the inner concave grooves (6) of two adjacent groove sets in the axial direction of the piston (2) are staggered.
8. the hydraulic cylinder with the clearance dynamic seal piston according to any one of claims 1 to 4, wherein an oil leakage recovery annular groove is formed in the cylinder cover (5) at a position corresponding to the piston rod (3), the oil leakage recovery annular groove is located on the inner side of an annular seal assembly between the cylinder cover (5) and the piston rod (3), an oil leakage recovery channel is further formed in the cylinder cover (5) along the radial direction of the oil leakage recovery channel, and the oil leakage recovery channel is communicated with the oil leakage recovery annular groove.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920323691.7U CN209761905U (en) | 2019-03-14 | 2019-03-14 | Hydraulic cylinder with clearance dynamic sealing piston |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920323691.7U CN209761905U (en) | 2019-03-14 | 2019-03-14 | Hydraulic cylinder with clearance dynamic sealing piston |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209761905U true CN209761905U (en) | 2019-12-10 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920323691.7U Expired - Fee Related CN209761905U (en) | 2019-03-14 | 2019-03-14 | Hydraulic cylinder with clearance dynamic sealing piston |
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| Country | Link |
|---|---|
| CN (1) | CN209761905U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110030225A (en) * | 2019-03-14 | 2019-07-19 | 徐州工程学院 | A kind of hydraulic cylinder with spacial seal piston |
-
2019
- 2019-03-14 CN CN201920323691.7U patent/CN209761905U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110030225A (en) * | 2019-03-14 | 2019-07-19 | 徐州工程学院 | A kind of hydraulic cylinder with spacial seal piston |
| CN110030225B (en) * | 2019-03-14 | 2024-03-19 | 徐州工程学院 | Hydraulic cylinder with clearance dynamic seal piston |
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| Date | Code | Title | Description |
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| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20191210 |
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| CF01 | Termination of patent right due to non-payment of annual fee |