CN211525542U - Multistage oil cylinder sealing ring assembly and hydraulic device - Google Patents

Multistage oil cylinder sealing ring assembly and hydraulic device Download PDF

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CN211525542U
CN211525542U CN201921541348.6U CN201921541348U CN211525542U CN 211525542 U CN211525542 U CN 211525542U CN 201921541348 U CN201921541348 U CN 201921541348U CN 211525542 U CN211525542 U CN 211525542U
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ring
sealing
lip
sealing ring
sealed body
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黄佑生
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Wuhan Rongsheng Sealing Technology Co ltd
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Wuhan Rongsheng Sealing Technology Co ltd
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Abstract

The utility model belongs to the technical field of the multistage oil cylinder is sealed, specifically provide multistage oil cylinder sealing washer subassembly and hydraulic means, main seal circle includes annular sealed body, and one end has outer lip and inner lip, encloses to close and forms the ring channel cross-section that extends around sealed body and be the U type, and outer lip is to the outside protrusion of sealed body, and inner lip is to the inboard protrusion of sealed body, has seted up at least one oil return channel on the inner lip, and oil return channel intercommunication ring channel is inboard with sealed body. The sealing ring component has the sealing performance of bearing high pressure and has the function of reducing back pressure, when the back pressure of the main sealing ring is too high, the sealing ring component flows through a small gap which is pushed outwards when the lip on the inner side of the body is pressed, and the sealing ring component is decompressed through the special oil return channel, so that the service life cycle of the sealing ring component is prolonged. The main seal has good flexibility and sealing performance, high tensile strength, impact resistance and difficult tearing and damage, and ensures the service life cycle of the seal ring assembly.

Description

Multistage oil cylinder sealing ring assembly and hydraulic device
Technical Field
The utility model belongs to the technical field of the multistage oil cylinder is sealed, concretely relates to multistage oil cylinder sealing washer subassembly and hydraulic means.
Background
The multi-stage oil cylinder sealing configuration is often related to in the field of the dumper, and the multi-stage oil cylinder of the traditional dumper is provided with two common Y-shaped sealing rings. The Y-shaped main seal can only bear high-pressure seal and has no function of reducing back pressure. When the piston rod moves under high pressure, the main seal is slightly infiltrated due to a plurality of factors, and the secondary seal completely prevents a small cavity between the main seal and the guide ring. The back pressure is easily generated in a small space, the back pressure cannot be reduced, a sealing element is damaged, the tension of the second Y-shaped ring is insufficient when the second Y-shaped ring is subjected to micro-pressure, oil scraping is not clean, and an oil film is epitaxially leaked. The bottom static seal adopts a dumbbell-shaped ring, and the strength is insufficient under high pressure. All affect the service life.
To be provided with
Figure DEST_PATH_GDA0002518062440000011
For example, the weight of the hydraulic oil filled in the small seeping space is only 6.3g, when excessive hydraulic oil seeps, high back pressure is generated and cannot be automatically reduced, the back pressure continuously rises along with the further squeezing of the seeped oil, and even can exceed 2-3 times of the normal working pressure (25Mpa), and the normal use of the sealing ring is easily damaged by the quite large back pressure.
Disclosure of Invention
The utility model aims at: the problem of among the prior art hydro-cylinder piston rod sealing effect poor is overcome.
For this, the utility model provides a multistage hydro-cylinder sealing washer subassembly, including main seal circle, main seal circle includes annular sealed body, sealed body one end has outer lip and interior lip, outer lip with interior lip encloses to close and forms and winds the ring channel that sealed body extends, outer lip are to the outside protrusion of sealed body, and interior lip is to the inboard protrusion of sealed body, and the cross-section of ring channel is the U type, and the bottom of ring channel is convex and is the flaring form along the direction of keeping away from the bottom, has seted up at least one oil return channel on the interior lip, and oil return channel intercommunication ring channel is inboard with sealed body.
Preferably, the oil return passage is located at an end of the inner lip.
Preferably, the inner side of the sealing body is provided with an annular secondary lip which is used for abutting against the outer surface of the piston rod and has an opening ring shape, and the secondary lip plays a supporting role.
Preferably, still include the guide ring and assist the sealing washer, main sealing washer, guide ring and assist the sealing washer and arrange in proper order along the piston rod axial, assist the sealing washer and include flanging and inside flanging, the flanging with enclose between the inside flanging and close and form the shallow mouth groove, the shallow mouth groove with the terminal surface of guide ring encloses and closes and form the oil storage space.
Preferably, the inner flange and the outer flange are respectively far away from each other from the root to the tip.
Preferably, the sealing ring assembly further comprises a dustproof ring, and a guide ring is arranged between the dustproof ring and the auxiliary sealing ring.
Preferably, the guide ring has an L-shaped interface.
Preferably, the sealing ring assembly further comprises a static sealing ring for filling an assembly gap between the cylinder sleeve and the end cover, one side of the static sealing ring, which is close to the cylinder sleeve, is provided with a circle of drum shape, and the drum shape is abutted against the inner side of the cylinder sleeve.
The utility model also provides a hydraulic sealing device, establish including piston rod and movably ground cover the outer cylinder liner of piston rod still includes foretell sealing washer subassembly hydraulic means for the hydraulic pressure axle, sealing washer subassembly hydraulic means for the hydraulic pressure axle fill in the piston rod with clearance is reserved in the assembly between the cylinder liner.
The utility model has the advantages that: the utility model provides a this kind of multistage oil cylinder sealing washer subassembly and hydraulic means, including the main seal circle, the main seal circle includes annular sealed body, sealed body one end has outer lip and interior lip, outer lip and interior lip enclose to close the ring channel that forms around sealed body extension, outer lip is to the outside protrusion of sealed body, interior lip is to the inboard protrusion of sealed body, the cross-section of ring channel is the U type, and the bottom of ring channel is convex and is the flaring form along the direction of keeping away from the bottom, at least one oil return channel has been seted up on the interior lip, oil return channel intercommunication ring channel is inboard with sealed body. The sealing ring component has the sealing performance of bearing high pressure and the function of reducing back pressure, when the back pressure of the main sealing ring is too high, the sealing ring component flows through a small gap which is pushed outwards when the lip on the inner side of the sealing body is pressed, and the service life of the sealing ring component is prolonged through pressure relief of the special oil return channel. In addition, the main sealing ring is high in tensile strength, impact-resistant, not easy to tear and damage, and good in flexibility and sealing performance.
The present invention will be described in further detail with reference to the accompanying drawings.
Drawings
Fig. 1 is an assembly schematic diagram of the multistage oil cylinder sealing ring assembly and the hydraulic sealing device of the present invention;
fig. 2 is a schematic view of the main seal ring end of the multi-stage oil cylinder seal ring assembly and the hydraulic seal device of the present invention;
fig. 3 is a schematic longitudinal sectional view of a main seal ring of the multi-stage oil cylinder seal ring assembly and the hydraulic sealing device of the present invention;
fig. 4 is a schematic view of the local back pressure of the multi-stage oil cylinder sealing ring assembly and the hydraulic sealing device of the present invention;
fig. 5 is a schematic pressure relief view of the multi-stage oil cylinder seal ring assembly and the hydraulic sealing device of the present invention;
fig. 6 is the auxiliary seal ring end schematic diagram of the multi-stage oil cylinder seal ring assembly and the hydraulic sealing device of the present invention.
Description of reference numerals: the anti-dust seal comprises a dust ring 1, an L-shaped guide ring 2, an auxiliary seal ring 3, a main seal ring 4, a static seal ring 5, a piston rod 6, a cylinder sleeve 7, an end cover 8, high-pressure oil 9, an outward flange 31, an inward flange 32, a shallow groove 33, an outward lip 41, an inward lip 42, an oil return channel 43, an annular groove 44, a protrusion 45 and a seal body 46.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, are not to be construed as limiting the present invention.
The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of the present invention, "a plurality" means two or more unless otherwise specified.
As shown in fig. 1 to 6, the utility model provides a multistage hydro-cylinder sealing washer subassembly, including main sealing washer 4, main sealing washer 4 includes annular sealing body 46, sealing body 46 one end has outer lip 41 and interior lip 42, outer lip 41 with interior lip 42 encloses to close and forms around the ring channel 44 that sealing body 46 extends, just outer lip 41 to sealing body 46's the outside protrusion, interior lip 42 to sealing body 46's inboard protrusion, ring channel 44's cross-section is the U type, just ring channel 44's bottom is arc and is the flaring form along the direction of keeping away from the bottom.
Therefore, the sealing ring assembly is mainly used for the main sealing ring 4 in the multi-stage telescopic oil cylinder. The piston rod 6 reciprocates relative to the cylinder sleeve 7, the sealing ring component is static relative to the cylinder sleeve 7, and sliding friction is formed between the sealing ring component and the piston rod 6. In the hydraulic working process, the main sealing ring 4 plays a main role in sealing and oil leakage prevention, and the auxiliary sealing ring 3 plays a further role in assisting and strengthening sealing and oil leakage prevention. Specifically, the sealing ring assembly is filled in an assembly reserved gap between the cylinder sleeve 7 and the piston rod 6, the main sealing ring 4 is close to a piston acting space, the auxiliary sealing ring 3 is close to the outside, the two sealing rings are separated by the guide ring, and the two sealing elements jointly act to form a sealing effect. A movable gap is arranged between the guide ring and the piston rod 6, an oil storage space is arranged between the end part of the auxiliary sealing ring 3 and the end part of the guide ring, the movable gap is communicated with the oil storage space, the end part of the main sealing ring 4 is tightly abutted against the other end part of the guide ring, and the other end of the main sealing ring 4 is provided with an annular groove 44 for temporarily storing a small amount of leaked high-pressure oil 9.
In the working process of the piston rod 6, high-pressure oil 9 exists in the action space of the piston rod 6, the high-pressure oil 9 can penetrate into the annular groove 44 in the main sealing ring 4 along with the time, the back pressure can continuously rise along with the further accumulation of the penetrated oil, when the back pressure reaches a certain threshold value, the high-pressure oil 9 flows into the movable gap through the oil return channel 43, and the oil in the movable gap can further flow into the oil storage space; when the back pressure drops below the threshold, continued inflow is automatically stopped. The oil return pressure relief function is periodically and automatically opened and closed, so that the effect of reducing the pressure is achieved.
The auxiliary sealing ring 3 plays a role of bidirectional sealing, one end of the auxiliary sealing ring prevents high-pressure oil 9 from leaking out, and the other end of the auxiliary sealing ring prevents external dust from entering the cylinder sleeve 7; on the other hand, the sealing ring can bear high pressure, and forms an oil storage space by enclosing with other sealing ring components, so that the function of releasing the back pressure of the main sealing ring 4 is achieved, and the integral sealing performance in micro-pressure can be improved.
The cross section of the annular groove 44 is U-shaped, specifically, the cross section along the axial direction is U-shaped, and the bottom of the annular groove 44 is arc-shaped and gradually expands along the direction away from the bottom. When the back pressure reaches a certain threshold value, the oil return function is automatically and repeatedly started to achieve the effect of pressure reduction, and the initial service cycle of the front oil cylinder of the dumper is prolonged by 40-50% compared with the prior art. The inner lip 42 also has a supporting function, and a trace amount of oil film extends out of the annular inner lip 42, so that the lubricating condition of subsequent related parts is improved, the abrasion is reduced, and the normal service cycle is prolonged.
Preferably, the main seal ring 4 includes a seal body 46, an end of the seal body 46 is provided with an outer lip 41 abutting against the cylinder liner 7 and an inner lip 42 abutting against the piston rod 6, and the annular groove 44 is formed by enclosing between the outer lip 41 and the inner lip 42. Therefore, the inner side and the outer side of the sealing body 46 are respectively abutted against the piston rod 6 and the cylinder sleeve 7, the tail end of the sealing body is forked to form the annular groove 44, and the annular groove 44 has the function of temporarily storing oil, so that the phenomenon that the trace leaked oil flows at the submerged position to form overhigh back pressure is avoided. When the annular groove 44 is filled with the high-pressure oil 9, the oil will automatically enter the pressure relief space through the oil return channel 43 to be relieved under the action of high pressure. In this embodiment, outer lip 41 and inner lip 42 all have the radian of outside expansion extension, play the effect that the pretension was pressed, if inner lip 42 outwards expands, whole main seal 4's seal body 46 contacts but the extrusion force is little with piston rod 6 during the assembly, mainly leans on hugging closely of inner lip 42 to push and form sealedly, and area of contact is little like this, and not only sealed effectual can also reduce frictional force.
Preferably, the oil return passage 43 is located at the end of the inner lip 42. The tip of the inner lip 42 is provided with a semi-open type oil return passage 43, and the high-pressure oil 9 enters the pressure relief space through the semi-open type oil return passage 43. In other implementation scenarios, the oil return passage 43 may also be a through hole opened at other places of the inner lip 42.
Preferably, a protrusion 45 is disposed on one side of the sealing body 46 close to the piston rod 6, and the protrusion 45 is pressed against the outer surface of the piston rod 6. Therefore, the inner lip 42 abuts against the outer surface of the piston rod 6 to play a role in sealing, the protrusion 45 plays a role in auxiliary sealing, and after the high-pressure oil 9 permeates into the gap between the inner lip 42 and the piston rod 6, the protrusion 45 can play a role in further permeation.
In a preferable scheme, the auxiliary sealing ring 3 comprises an outer flanging 31 and an inner flanging 32, a shallow groove 33 is formed by enclosing the outer flanging and the inner flanging, and the shallow groove 33 and the end face of the guide ring enclose the oil storage space. Therefore, the inward flange 32 and the outward flange 31 are respectively assembled with the piston rod 6 and the cylinder sleeve 7 in a squeezing and sealing mode, and the inward flange 32 also plays a role in scraping oil and prevents oil on the piston rod 6 from leaking out. The auxiliary sealing ring 3 is improved on the existing Y-shaped ring, the V-shaped groove bottom of the Y-shaped ring is designed into a shallow groove 33, the inner and outer sealing lips are improved into inner and outer special extrusion type flanging lips, namely, the inner flanging 32 and the outer flanging 31 are both outwards opened and extended, during assembly, the inner flanging 32 is extruded and tightly attached to the piston rod 6, other parts of the body of the auxiliary sealing ring 3 are smaller than the extrusion force of the piston rod 6, and the inner flanging 32 plays a main sealing role, so that the friction force between the whole auxiliary sealing ring 3 and the piston rod 6 is reduced. The auxiliary sealing ring 3 has excellent dynamic and static sealing performance, can bear high-pressure ground impact, can ensure outward leakage of a scraping oil film during micro-pressure, and can prevent pollutants from invading into a cavity of a working space to influence the efficacy of a sealing ring component. If the dust ring 1 is accidentally disabled, dust and rainwater can permeate into the front cavity when returning along with the piston rod 6, and the inward flanging lip has a dustproof effect, so that invasion of sewage is thoroughly prevented, cleanliness in the cavity is guaranteed, and safety and reliability of the sealing element are guaranteed.
Preferably, the inner flanging and the outer flanging are respectively far away from each other from the root to the tip. The turn-ups leans out the extension, and when the assembly, the turn-ups supports earlier to lean on and compresses tightly, can reduce the extrusion force between sealing washer body and the piston rod 6 like this to reduce frictional force, the turn-ups plays main sealed effect.
Preferably, the sealing ring assembly further comprises a dustproof ring 1, and a guide ring is arranged between the dustproof ring 1 and the auxiliary sealing ring 3. The dustproof ring 1 plays a dustproof role. The guide ring is L type guide ring 2, and two L type guide ring 2 symmetries are arranged back to back, play the effect of direction, and reserve between L type guide ring 2 and the piston rod 6 and have the activity clearance.
Preferably, the sealing ring assembly further comprises a static sealing ring 5 used for filling an assembly gap between the cylinder sleeve 7 and the end cover 8, one side of the static sealing ring 5, which is close to the cylinder sleeve 7, is provided with a circle of drum shape, and the drum shape abuts against the inner side of the cylinder sleeve 7. Therefore, the existing bottom static seal is generally a dumbbell-shaped ring, the section size is single and thin, and the strength is insufficient when high pressure is borne. The static seal circle 5 of this scheme adoption is on dumbbell ring's basis, and cross sectional dimension has carried out the perfection, and the resilience force is strengthened, and anti extrusion nature reinforcing, permanent deformation volume are little, and is more resistant high pressure, is fit for the pressure rapid change. When bearing high pressure and low pressure, the whole performance of the sealing package is ensured and perfected.
The utility model also provides a hydraulic means, establish including piston rod 6 and movably ground cover cylinder liner 7 outside the piston rod 6 still includes multistage hydro-cylinder sealing washer subassembly, piston rod 6 sealing washer subassembly fill in piston rod 6 with clearance is reserved in the assembly between the cylinder liner 7.
The utility model has the advantages that: the utility model provides a this kind of multistage oil cylinder sealing washer subassembly and hydraulic means, including the main seal circle, the main seal circle includes annular sealed body, sealed body one end has outer lip and interior lip, outer lip encloses with interior lip and closes the ring channel that forms around sealed body extension, and outer lip is to the outside protrusion of sealed body, interior lip is to the inboard protrusion of sealed body, the cross-section of ring channel is the U type, and the bottom of ring channel is convex and is the flaring form along the direction of keeping away from the bottom, at least one oil return channel has been seted up on the interior lip, oil return channel intercommunication ring channel is inboard with sealed body. The sealing ring component has the sealing performance of bearing high pressure and the function of reducing back pressure, when the back pressure of the main sealing ring is too high, the sealing ring component flows through a small gap which is pushed outwards when the lip on the inner side of the sealing body is pressed, and the service life of the sealing ring component is prolonged through pressure relief of the special oil return channel. In addition, the main sealing ring is high in tensile strength, impact-resistant, not easy to tear and damage, and good in flexibility and sealing performance.
The above examples are merely illustrative of the present invention and should not be construed as limiting the scope of the invention, which is intended to be covered by the claims and any design similar or equivalent to the scope of the invention.

Claims (9)

1. Multistage hydro-cylinder sealing washer subassembly, including main sealing washer, its characterized in that: the main seal circle includes annular sealed body, sealed body one end has outer lip and inner lip, outer lip with inner lip encloses to close and forms around the ring channel that sealed body extends, outer lip is to the outside protrusion of sealed body, and inner lip is to the inboard protrusion of sealed body, and the cross-section of ring channel is the U type, and the bottom of ring channel is convex and is the flaring form along the direction of keeping away from the bottom, has seted up at least one oil return channel on the inner lip, and oil return channel intercommunication ring channel is inboard with sealed body.
2. The multi-stage cylinder seal ring assembly of claim 1, wherein: the oil return passage is located at the tail end of the inner lip.
3. The multi-stage cylinder seal ring assembly of claim 1, wherein: the inner side of the sealing body is provided with an annular secondary lip which is used for abutting against the outer surface of the piston rod and has an opening, and the secondary lip plays a supporting role.
4. The multi-stage cylinder seal ring assembly of claim 1, wherein: still include the guide ring and assist the sealing washer, main sealing washer, guide ring and assist the sealing washer and arrange in proper order along the piston rod axial, assist the sealing washer and include flanging and inside flanging, the flanging with enclose between the inside flanging and close and form the shallow mouth groove, the shallow mouth groove with the terminal surface of guide ring encloses and closes and form the oil storage space.
5. The multi-stage cylinder seal ring assembly according to claim 4, wherein: the inner flanging and the outer flanging are respectively far away from each other from the root to the tip.
6. The multi-stage cylinder seal ring assembly according to claim 4, wherein: the sealing ring assembly further comprises a dustproof ring, and a guide ring is arranged between the dustproof ring and the auxiliary sealing ring.
7. The multi-stage cylinder seal ring assembly according to claim 6, wherein: the interface of the guide ring is L-shaped.
8. The multi-stage cylinder seal ring assembly of claim 1, wherein: the sealing ring assembly further comprises a static sealing ring used for filling an assembly gap between the cylinder sleeve and the end cover, wherein a circle of drum shape is arranged on one side, close to the cylinder sleeve, of the static sealing ring, and the drum shape is abutted to the inner side of the cylinder sleeve.
9. Hydraulic means establishes including piston rod and movably the cover the outer cylinder liner of piston rod, its characterized in that: the multi-stage oil cylinder sealing ring assembly as claimed in any one of claims 5 to 8 is further included, and the sealing ring assembly is filled in an assembly reserved gap between the piston rod and the cylinder sleeve.
CN201921541348.6U 2019-09-17 2019-09-17 Multistage oil cylinder sealing ring assembly and hydraulic device Active CN211525542U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201921541348.6U CN211525542U (en) 2019-09-17 2019-09-17 Multistage oil cylinder sealing ring assembly and hydraulic device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201921541348.6U CN211525542U (en) 2019-09-17 2019-09-17 Multistage oil cylinder sealing ring assembly and hydraulic device

Publications (1)

Publication Number Publication Date
CN211525542U true CN211525542U (en) 2020-09-18

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Family Applications (1)

Application Number Title Priority Date Filing Date
CN201921541348.6U Active CN211525542U (en) 2019-09-17 2019-09-17 Multistage oil cylinder sealing ring assembly and hydraulic device

Country Status (1)

Country Link
CN (1) CN211525542U (en)

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