Hydraulic expansion joint

Abstract

The utility model relates to the technical field of hydraulic machinery, in particular to a hydraulic expansion joint. One end of the telescopic outer pipe is connected with the first hydraulic connector, one end of the telescopic inner pipe is connected with the second hydraulic connector, the telescopic outer pipe and the telescopic inner pipe are coaxially nested, and the telescopic inner pipe can freely reciprocate in the length direction of the telescopic outer pipe. A sealing mechanism is arranged between the inner pipe wall of the telescopic outer pipe and the outer pipe wall of the telescopic inner pipe, and a telescopic dust cover is arranged between the telescopic outer pipe and the telescopic inner pipe in a sleeving mode. One end of the dustproof cover is detachably sealed and fixedly connected with the outer pipe wall, close to one side of the first hydraulic joint, of the telescopic outer pipe, and the other end of the dustproof cover is detachably sealed and fixedly connected with the outer pipe wall, close to one side of the second hydraulic joint, of the telescopic inner pipe; after the prior art is improved, the dustproof and sealing performance between the telescopic outer pipe and the telescopic inner pipe is good, and the service life of the hydraulic telescopic joint is long.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic machinery, in particular to a hydraulic expansion joint. Background Art

[0002] In a hydraulic system, when the hydraulic pipeline needs to be extended or retracted in the length direction, the current existing technology realizes this by using the S-shaped pipeline of the hydraulic hose to bend and deform. However, this implementation method requires a large installation space, especially when the space through which the hydraulic pipeline passes is relatively narrow, this method is difficult to implement; in addition, this implementation method will cause the hose to bend and deform repeatedly, greatly shortening its lifespan.

[0003] In view of this, a Chinese patent document with authorization number CN202091683U discloses a hydraulic telescopic joint, including a first hydraulic joint, a second hydraulic joint, a coaxially nested telescopic outer tube and a telescopic inner tube, wherein the telescopic inner tube is placed in the telescopic outer tube; the first hydraulic joint is connected to one end of the telescopic outer tube, and the other end of the telescopic outer tube is threadedly connected to the dust cover through a thread set at the end of the telescopic outer tube, and the telescopic inner tube and the inner hole clearance of the dust cover are matched; the second hydraulic joint is connected to one end of the telescopic inner tube, and the other end of the telescopic inner tube is freely placed in the telescopic outer tube, and an annular groove is opened at the port near the other end of the telescopic inner tube, and a retaining ring and a sealing ring are arranged in the annular groove from the inside to the outside. Although the clearance between the inner hole of the telescopic inner tube and the dust cover has a certain protective effect, when dust accumulates at the end of the telescopic inner tube away from the dust cover, the dust is easily brought into the gap between the telescopic outer tube and the telescopic inner tube by contracting the hydraulic telescopic joint to move the telescopic outer tube and the telescopic inner tube closer to each other. During the extension and contraction of the hydraulic telescopic joint, serious wear between the inner wall of the telescopic outer tube and the outer wall of the telescopic inner tube is likely to occur, resulting in a decrease in sealing and affecting the service life.

[0004] Therefore, it is necessary to improve the deficiencies in the above prior art. Summary of the invention

[0005] The technical problem to be solved by the utility model is to provide a hydraulic expansion joint in view of the above-mentioned deficiencies in the prior art, so as to solve the problem in the prior art that the sealing performance is reduced and the service life is affected due to the poor dustproof effect.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a hydraulic telescopic joint, comprising a first hydraulic joint, a second hydraulic joint, a telescopic outer tube connected to the first hydraulic joint at one end, and a telescopic inner tube connected to the second hydraulic joint at one end, the telescopic outer tube and the telescopic inner tube are coaxially nested and the telescopic inner tube can freely reciprocate along the length direction of the telescopic outer tube, a sealing mechanism is provided between the inner tube wall of the telescopic outer tube and the outer tube wall of the telescopic inner tube, a telescopic dust cover is sleeved between the telescopic outer tube and the telescopic inner tube, one end of the dust cover is detachably sealed and fixedly connected to the outer tube wall of the telescopic outer tube on the side close to the first hydraulic joint, and the other end is detachably sealed and fixedly connected to the outer tube wall of the telescopic inner tube on the side close to the second hydraulic joint.

[0007] By adopting the above technical solution, the dust cover is sleeved on the periphery of the telescopic outer tube and the telescopic inner tube, and the two ends are detachably sealed and fixedly connected to the outer tube walls of the telescopic outer tube and the telescopic inner tube. When the first hydraulic joint or the second hydraulic joint drives the telescopic outer tube or the telescopic inner tube respectively, the dust cover can be driven to retract accordingly. Since the two ends of the dust cover are sealed and connected to the telescopic outer tube and the telescopic inner tube respectively, dust cannot enter between the telescopic outer tube and the telescopic inner tube during the telescopic process of the joint, so that the dustproof and sealing between the telescopic outer tube and the telescopic inner tube are better, and the service life of the hydraulic telescopic joint is extended.

[0008] The above technical solution is further configured as follows: internal threads are provided at both ends of the dust cover, external threads matching the internal threads are provided on the outer tube walls of the telescopic outer tube and the telescopic inner tube, and the two ends of the dust cover are threadedly connected to the external threads on the telescopic outer tube and the telescopic inner tube through the internal threads respectively.

[0009] By adopting the above technical solution, the two ends of the dust cover are connected with the telescopic outer tube and the telescopic inner tube through threaded connection to achieve a sealed and detachable fixed connection.

[0010] The above technical solution is further configured as follows: the middle portion of the dust cover is a corrugated telescopic tubular structure.

[0011] By adopting the above technical solution, by setting the middle part of the dust cover as a corrugated telescopic tubular structure, when the joint is extended or retracted, the dust cover can adjust its length accordingly.

[0012] The above technical solution is further configured as follows: the sealing mechanism includes a first sealing groove arranged on the outer tube wall of the telescopic inner tube close to one end of the telescopic outer tube and a first sealing ring installed on the first sealing groove, and the outer peripheral side of the first sealing ring can be sealed and fitted with the inner tube wall of the telescopic outer tube.

[0013] By adopting the above technical solution, the gap between the telescopic outer tube and the telescopic inner tube is sealed and blocked by the first sealing ring installed on the outer tube wall of the telescopic inner tube, thereby preventing the fluid in the joint from flowing out of the gap.

[0014] The above technical solution is further configured as follows: the sealing mechanism also includes a second sealing groove arranged on the inner tube wall of the telescopic outer tube close to one end of the telescopic inner tube and a second sealing ring installed on the second sealing groove, and the inner circumference of the second sealing ring can be sealed and fitted with the outer tube wall of the telescopic inner tube.

[0015] By adopting the above technical solution, the gap between the telescopic outer tube and the telescopic inner tube is sealed by a second sealing ring installed on the inner tube wall of the telescopic outer tube, which can further improve the sealing performance. At the same time, the cooperation between the first sealing ring and the second sealing ring can make the joint more balanced and stable when telescopically moving.

[0016] The above technical solution is further configured as follows: a first step is provided on the inner tube wall of the telescopic outer tube, and the side surface of the first step can abut against the side surface of the telescopic inner tube when the joint is in a contracted state; a second step is provided on the outer tube wall of the telescopic inner tube, and the side surface of the second step can abut against the side surface of the telescopic outer tube when the joint is in a contracted state.

[0017] By adopting the above technical solution and providing the first step and the second step, the telescopic outer tube and the telescopic inner tube can be limited when the joint is in a contracted state.

[0018] The above technical solution is further configured as follows: the first hydraulic joint includes a first nut rotatably connected to the telescopic outer tube, the second hydraulic joint includes a second nut rotatably connected to the telescopic inner tube, the outer sides of the first nut and the second nut are both provided with mounting through holes, a clamping ring is transitionally connected in the mounting through holes, a clamping groove is provided on the outer tube wall of the telescopic outer tube and the telescopic inner tube, one end of the clamping ring is inserted into the mounting through hole, and the other end is wrapped around and clamped in the clamping groove.

[0019] By adopting the above technical solution, the clamping ring is inserted through the installation hole and wrapped around the clamping groove, so that the clamping ring can limit the axial movement between the first nut and the telescopic outer tube. At the same time, when the first nut rotates, the clamping ring can be driven to rotate in the clamping groove, thereby realizing an axially fixed rotatable connection, which facilitates the threaded installation between the first nut and the external pipe connector; the structure and installation process of the second nut are similar and will not be repeated.

[0020] The above technical solution is further configured as follows: a limiting portion capable of abutting against a retaining ring is provided on the side of the first nut and the second nut close to the dust cover, and the inner side wall of the limiting portion extends toward the axis and is respectively gap-matched with the outer tube wall of the telescopic outer tube and the telescopic inner tube.

[0021] By adopting the above technical solution, the limiting part is provided to simultaneously limit the circumferential position of the clamping ring, the first nut and the second nut, so that the rotation between the first nut and the telescopic outer tube and the second nut and the telescopic inner tube is more stable.

[0022] The above technical solution is further configured as follows: a third sealing groove is provided on the outer tube wall of the telescopic outer tube and the telescopic inner tube away from the dust cover, a third sealing ring is installed on the third sealing groove, and the third sealing groove is located in the screw hole of the first nut or the second nut.

[0023] By adopting the above technical solution, when the joint is installed, the first nut or the second nut is threadedly connected to the outer tube wall of the external pipe connector, and the telescopic outer tube or the telescopic inner tube extends into the inner tube wall of the external pipe connector and achieves a sealed connection through the third sealing ring.

[0024] The beneficial effects achieved by the utility model are: good dustproof and sealing performance between the telescopic outer tube and the telescopic inner tube, and long service life of the hydraulic telescopic joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model;

[0026] Figure 2 It is a schematic diagram of the explosion structure of an embodiment of the utility model;

[0027] Figure 3 It is a cross-sectional view of an embodiment of the utility model;

[0028] Figure 4 It is a structural schematic diagram of the telescopic outer tube in the embodiment of the utility model;

[0029] Figure 5 It is a structural schematic diagram of the telescopic inner tube in an embodiment of the utility model. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] like Figure 1-5As shown in the figure, a hydraulic telescopic joint comprises a first hydraulic joint 1, a second hydraulic joint 2, a telescopic outer tube 3 connected to the first hydraulic joint 1 at one end, and a telescopic inner tube 4 connected to the second hydraulic joint 2 at one end, the telescopic outer tube 3 and the telescopic inner tube 4 are coaxially nested and the telescopic inner tube 4 can freely reciprocate along the length direction of the telescopic outer tube 3, a sealing mechanism 5 is provided between the inner tube wall of the telescopic outer tube 3 and the outer tube wall of the telescopic inner tube 4, a telescopic dust cover 6 is sleeved between the telescopic outer tube 3 and the telescopic inner tube 4, and internal threads 60 are provided at both ends of the dust cover 6, and external threads 61 matching the internal threads 60 are provided on the outer tube walls of the telescopic outer tube 3 and the telescopic inner tube 4, and the two ends of the dust cover 6 are threadedly connected to the external threads 61 on the telescopic outer tube 3 and the telescopic inner tube 4 through the internal threads 60, and the middle part of the dust cover 6 is a corrugated telescopic tubular structure.

[0032] The sealing mechanism 5 includes a first sealing groove 51 provided on the outer tube wall of the telescopic inner tube 4 near one end of the telescopic outer tube 3, a first sealing ring 52 installed on the first sealing groove 51, a second sealing groove 53 provided on the inner tube wall of the telescopic outer tube 3 near one end of the telescopic inner tube 4, and a second sealing ring 54 installed on the second sealing groove 53. The outer peripheral side of the first sealing ring 52 can be sealed and fitted with the inner tube wall of the telescopic outer tube 3, and the inner peripheral side of the second sealing ring 54 can be sealed and fitted with the outer tube wall of the telescopic inner tube 4. The cooperation between the first sealing ring 52 and the second sealing ring 54 can not only improve the sealing performance but also make the joint more balanced and stable when telescopically moving.

[0033] A first step 30 is provided on the inner tube wall of the telescopic outer tube 3, and the side surface of the first step 30 can abut against the side surface of the telescopic inner tube 4 when the joint is in a contracted state. A second step 40 is provided on the outer tube wall of the telescopic inner tube 4, and the side surface of the second step 40 can abut against the side surface of the telescopic outer tube 3 when the joint is in a contracted state. The first step 30 and the second step 40 are used to limit the telescopic outer tube 3 and the telescopic inner tube 4 in the contracted state.

[0034] The first hydraulic joint 1 includes a first nut 11 rotatably connected to the telescopic outer tube 3, and the second hydraulic joint 2 includes a second nut 21 rotatably connected to the telescopic inner tube 4. The outer sides of the first nut 11 and the second nut 21 are both provided with a mounting through hole 12, and a snap ring 13 is connected in transition fit in the mounting through hole 12. A snap groove 14 is provided on the outer tube wall of the telescopic outer tube 3 and the telescopic inner tube 4, and one end of the snap ring 13 is inserted into the mounting through hole 12, and the other end is clamped in the snap groove 14. A limiting portion 15 capable of abutting against the snap ring 13 is provided on the side of the first nut 11 and the second nut 21 close to the dust cover 6, and the inner side wall of the limiting portion 15 extends toward the axis and is respectively fitted with a clearance with the outer tube wall of the telescopic outer tube 3 and the telescopic inner tube 4. The clamping ring 13 is inserted through the mounting hole 12 and is clamped into the clamping groove 14 around it, so that the clamping ring 13 can limit the axial movement between the first nut 11 and the telescopic outer tube 3. At the same time, when the first nut 11 rotates, the clamping ring 13 can be driven to rotate in the clamping groove 14, thereby realizing an axially fixed rotatable connection, which is convenient for the threaded installation between the first nut 11 and the external pipe connector; the structure and installation process of the second nut 21 are the same and will not be repeated.

[0035] A third sealing groove 7 is provided on the outer tube wall of the telescopic outer tube 3 and the telescopic inner tube 4 away from the dust cover 6, and a third sealing ring 8 is installed on the third sealing groove 7. The third sealing groove 7 is located in the screw hole of the first nut 11 or the second nut 21. When the joint is installed, the first nut 11 or the second nut 21 is threadedly connected to the outer tube wall of the external pipe connecting piece, and the telescopic outer tube 3 or the telescopic inner tube 4 extends into the inner tube wall of the external pipe connecting piece and realizes a sealed connection through the third sealing ring 8.

[0036] In the above embodiment, the dust cover 6 is sleeved on the periphery of the telescopic outer tube 3 and the telescopic inner tube 4 and the two ends are respectively threadedly connected to the outer tube walls of the telescopic outer tube 3 and the telescopic inner tube 4. When the first hydraulic joint 1 or the second hydraulic joint 2 drives the telescopic outer tube 3 or the telescopic inner tube 4 respectively, the dust cover 6 can be driven to extend and retract accordingly. Since the two ends of the dust cover 6 are respectively threadedly sealed with the telescopic outer tube 3 and the telescopic inner tube 4, dust cannot enter between the telescopic outer tube 3 and the telescopic inner tube 4 during the extension and retraction of the joint, thereby improving the dustproof and sealing properties between the telescopic outer tube 3 and the telescopic inner tube 4 and extending the service life of the hydraulic telescopic joint.

Claims

1. A hydraulic expansion joint, comprising a first hydraulic joint, a second hydraulic joint, a expansion outer tube connected to the first hydraulic joint at one end, and a expansion inner tube connected to the second hydraulic joint at one end, wherein the expansion outer tube and the expansion inner tube are coaxially nested and the expansion inner tube can freely reciprocate along the length direction of the expansion outer tube, and a sealing mechanism is provided between the inner tube wall of the expansion outer tube and the outer tube wall of the expansion inner tube, characterized in that: A telescopic dust cover is sleeved between the telescopic outer tube and the telescopic inner tube, one end of the dust cover is detachably sealed and fixedly connected to the outer tube wall of the telescopic outer tube near the first hydraulic joint, and the other end of the dust cover is detachably sealed and fixedly connected to the outer tube wall of the telescopic inner tube near the second hydraulic joint.

2. A hydraulic expansion joint according to claim 1, characterized in that: The two ends of the dust cover are provided with internal threads, and the outer tube walls of the telescopic outer tube and the telescopic inner tube are provided with external threads matching the internal threads. The two ends of the dust cover are respectively threadedly connected with the external threads on the telescopic outer tube and the telescopic inner tube through the internal threads.

3. A hydraulic expansion joint according to claim 2, characterized in that: The middle part of the dust cover is a corrugated telescopic tubular structure.

4. A hydraulic expansion joint according to any one of claims 1 to 3, characterized in that: The sealing mechanism comprises a first sealing groove arranged on the outer tube wall of the telescopic inner tube near one end of the telescopic outer tube and a first sealing ring installed on the first sealing groove, wherein the outer peripheral side of the first sealing ring can be sealed and fitted with the inner tube wall of the telescopic outer tube.

5. A hydraulic expansion joint according to claim 4, characterized in that: The sealing mechanism also includes a second sealing groove provided on the inner tube wall of the telescopic outer tube near one end of the telescopic inner tube and a second sealing ring installed on the second sealing groove, wherein the inner circumference of the second sealing ring can be sealed and fitted with the outer tube wall of the telescopic inner tube.

6. A hydraulic expansion joint according to claim 5, characterized in that: A first step is provided on the inner tube wall of the telescopic outer tube, and the side surface of the first step can abut against the side surface of the telescopic inner tube when the joint is contracted. A second step is provided on the outer tube wall of the telescopic inner tube, and the side surface of the second step can abut against the side surface of the telescopic outer tube when the joint is contracted.

7. A hydraulic expansion joint according to claim 6, characterized in that: The first hydraulic joint includes a first nut rotatably connected to the telescopic outer tube, and the second hydraulic joint includes a second nut rotatably connected to the telescopic inner tube. The outer sides of the first nut and the second nut are both provided with mounting through holes, and a clamping ring is transitionally connected in the mounting through holes. The outer tube walls of the telescopic outer tube and the telescopic inner tube are both provided with a clamping groove, and one end of the clamping ring is inserted into the mounting through hole, and the other end is wrapped around and clamped in the clamping groove.

8. A hydraulic expansion joint according to claim 7, characterized in that: The first nut and the second nut are provided with a limiting portion capable of abutting against the clamping ring on the side surface close to the dust cover, and the inner side wall of the limiting portion extends toward the axis and is respectively matched with the outer tube wall of the telescopic outer tube and the telescopic inner tube.

9. A hydraulic expansion joint according to claim 8, characterized in that: A third sealing groove is provided on the outer tube wall of the telescopic outer tube and the telescopic inner tube away from the dust cover, a third sealing ring is installed on the third sealing groove, and the third sealing groove is located in the screw hole of the first nut or the second nut.

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