Anti-rotation self-guiding anti-unbalance multi-stage oil cylinder

Abstract

The application relates to the technical field of hydraulic devices, and discloses a self-guiding anti-yaw multi-stage oil cylinder which is prevented from rotating and can resist eccentric load. The outer part of a cylinder barrel of the oil cylinder is designed as a sleeve which moves together with a hydraulic cylinder piston rod in an extending and retracting mode, and the sleeve is provided with a guide sleeve and a rotation-stopping pin, so that the rotation problem of the piston rod in a movement process is solved, and the rotation-preventing function is realized. The inner matching surface of the sleeve is welded with copper and then processed, so that the anti-yaw and self-guiding functions are realized.

Description

Technical Field

[0001] This application relates to the field of hydraulic transmission technology, for example to a self-guided anti-rotation and anti-eccentric load multi-stage hydraulic cylinder. Background Technology

[0002] Multistage hydraulic cylinders are widely used in heavy lifting scenarios of AGVs and other equipment. They are fixed by the cylinder body connection hole, and the piston rod end is a free suspended end. A pull rope encoder measures the extension and retraction stroke of the piston rod. The support plate must not rotate. During the movement of the AGV, the anti-rotation self-guiding anti-eccentric load multistage cylinder will maintain the state of lifting the heavy object. When the AGV starts and stops, there will be a large acceleration that will generate eccentric load. Operating under eccentric load conditions will lead to a shortened life of the hydraulic cylinder and problems such as oil leakage. Utility Model Content

[0003] To solve the aforementioned technical problems, this utility model provides a multi-stage hydraulic cylinder with anti-rotation self-guided anti-eccentric load; the cylinder barrel is designed with an external sleeve that moves together with the extension and retraction of the hydraulic cylinder piston rod, and is equipped with a guide sleeve and an anti-rotation pin to solve the problem of piston rod rotation during movement and achieve the anti-rotation function; the inner mating surface of the sleeve is welded with copper and then machined to achieve the anti-eccentric load and self-guided functions.

[0004] The technical solution adopted to solve its technical problem is:

[0005] This utility model provides a self-guided anti-eccentric load multi-stage hydraulic cylinder, including a cylinder body, a piston rod assembly, a piston, a guide sleeve, a guide ring, an inner support cylinder, and an outer support cylinder, all of which are arranged coaxially.

[0006] The piston rod assembly is a three-stage nested structure, including the outermost first-stage piston rod, the second-stage piston rod in the middle, and the innermost third-stage piston rod. The three are coaxial and extend and retract relative to each other along the axial direction.

[0007] The piston is axially fixed to the first end of the third-stage piston rod, and radially fits against the inner wall of the second-stage piston rod to form a sliding fit. The piston at the end of the second-stage piston rod radially fits against the inner wall of the first-stage piston rod to form a sliding fit. The piston at the end of the first-stage piston rod radially fits against the inner wall of the cylinder to form a sliding fit.

[0008] The inner support cylinder is coaxially fitted onto the outer side of the cylinder body; the inner surface of the inner support cylinder is machined with an anti-rotation groove that matches the outer surface of the cylinder body, forming a sliding channel to accommodate the anti-rotation pin.

[0009] The outer support cylinder is coaxially fitted onto the outside of the inner support cylinder and connected to the three-stage piston rod via a connecting ring and a support plate. The inner surface of the outer support cylinder is machined with an anti-rotation groove that matches the outer surface of the inner support cylinder, forming a sliding channel to accommodate the anti-rotation pin.

[0010] The guide sleeve is coaxially press-fitted onto the inner wall of the cylinder head. The outer ring of the guide sleeve is clearance-fitted with the inner wall of the cylinder, and the inner ring is sliding-fitted with the outer wall of the first-stage piston rod.

[0011] The guide ring has a clearance fit between the outer ring and the inner wall of the inner support cylinder, and the inner ring is threaded to the outer surface of the cylinder body.

[0012] Preferably, it also includes a fastener, which includes an internal hexagonal screw, a set screw one, and a set screw two.

[0013] The second set screw is used to prevent the anti-rotation pin from coming out;

[0014] The internal hexagon screw and the set screw work together to fix the connecting ring, the support plate, the outer support cylinder, and the three-stage piston rod.

[0015] Preferably, it also includes a sealing assembly, which includes a retaining ring, a shaft seal, an O-ring retaining ring, an O-ring one, an O-ring two, and a piston seal;

[0016] The retaining ring, shaft seal, and O-ring are all embedded in the circumferential groove of the guide sleeve, located between the mating surfaces of the guide sleeve and the inner wall of the cylinder, to prevent oil leakage.

[0017] The piston seal is fitted onto the mating surface between the first-stage piston rod and the cylinder body to prevent internal leakage of oil.

[0018] Preferably, it further includes a guide support assembly, which includes a guide strip for the shaft and a guide strip for the hole;

[0019] The shaft guide belt is fitted to the mating surface of the piston rod assembly and the guide sleeve, and the hole guide belt is fitted to the mating surface of the cylinder and the piston, to provide support and guidance during the extension and retraction of the piston rod assembly.

[0020] Preferably, it also includes a dustproof ring, which is fitted to the end of the guide sleeve to prevent foreign objects from being brought into the cylinder.

[0021] Preferably, it also includes baffle one and baffle two, which are located at the axial connection between the first-stage piston rod and the second-stage piston rod, and at the axial connection between the second-stage piston rod and the third-stage piston rod, respectively, to realize axial force transmission and limit piston stroke.

[0022] The anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder provided in this application can achieve the following technical effects:

[0023] (1) This utility model effectively prevents the rotation of the piston rod during the extension and retraction process by using the anti-rotation groove and anti-rotation pin of the cylinder and the inner support cylinder, as well as the anti-rotation connection structure of the support plate and the piston rod, and meets the usage requirement that the support plate does not rotate under the lifting condition of the AGV trolley.

[0024] (2) The copper contact surface and multiple clearance fit structure are adopted to disperse the eccentric load, guide the cylinder to move in the correct direction, avoid damage to the cylinder caused by eccentric load, and significantly improve the service life of the cylinder under complex working conditions.

[0025] (3) By setting up multiple sealing components, internal and external leakage of oil can be effectively prevented, ensuring the hydraulic transmission efficiency of the cylinder and reducing the failure rate;

[0026] (4) The components are tightly connected and work together to ensure anti-rotation, anti-eccentric load, self-guiding and sealing functions. It is suitable for scenarios with high requirements for cylinder performance, such as AGV trolley lifting heavy objects. It is highly practical.

[0027] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0028] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations and drawings do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are shown as similar elements. The drawings are not to be scaled. And wherein:

[0029] Figure 1 This is a schematic diagram of the structure of the anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder provided in the embodiments of this disclosure;

[0030] Figure label:

[0031] 1. Baffle 1; 2. Baffle 2; 3. Cylinder body; 4. First-stage piston rod; 5. Second-stage piston rod; 6. Third-stage piston rod; 7. Piston; 8. Outer support cylinder; 9. Inner support cylinder; 10. Guide sleeve; 11. Guide ring;

[0032] 12. Connecting ring; 13. Support plate; 14. Socket head screw; 15. Set screw one; 16. Dust seal; 17. Retaining ring; 18. Shaft seal; 19. Shaft guide band; 20. O-ring retaining ring; 21. O-ring one; 22. O-ring two; 23. Hole guide band; 24. Piston seal; 25. Set screw two; 26. Anti-rotation pin. Detailed Implementation

[0033] To provide a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this disclosure. In the following technical description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other cases, well-known structures and devices may be simplified in their depiction to simplify the drawings.

[0034] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this disclosure described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0035] In this disclosure, the terms "upper," "lower," "inner," "middle," "outer," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for better description of the embodiments of this disclosure and their implementations, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to require them to be constructed and operated in a specific orientation. Furthermore, some of the aforementioned terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in the embodiments of this disclosure according to the specific circumstances.

[0036] Furthermore, the terms "set up," "connect," and "fix" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0037] It should be noted that, unless otherwise specified, the embodiments and features described in the present disclosure can be combined with each other.

[0038] Combination Figure 1 As shown, this embodiment of the present disclosure provides a self-guided anti-rotation and anti-eccentric load multi-stage hydraulic cylinder, including a baffle 1, a baffle 2, a cylinder body 3, a first-stage piston rod 4, a second-stage piston rod 5, a third-stage piston rod 6, a piston 7, an outer support cylinder 8, an inner support cylinder 9, a guide sleeve 10, a guide ring 11, a connecting ring 12, a support plate 13, an internal hexagon screw 14, a set screw 15, a dust seal 16, a retaining ring 17, a shaft seal 18, a shaft guide band 19, an O-ring retaining ring 20, an O-ring 1 21, an O-ring 22, a hole guide band 23, a piston seal 24, a set screw 25, and an anti-rotation pin 26.

[0039] The cylinder body 3 and the outer surface of the inner support cylinder 9 are machined with matching anti-rotation grooves, as are the inner surfaces of the inner support cylinder 9 and the outer support cylinder 8. The anti-rotation pin 26 is assembled in the anti-rotation groove and is limited by the set screw 25, which is a hexagonal flat-end set screw to prevent the anti-rotation pin 26 from coming out. When the piston rod assembly extends or retracts, the anti-rotation pin 26 slides along the anti-rotation groove, limiting the relative rotation between the outer support cylinder 8 and the cylinder body 3, thereby achieving anti-rotation of the piston rod assembly. At the same time, the outer support cylinder 8 is connected to the third-stage piston rod 6 through the connecting ring 12, and the support plate 13 is fixed to the outer support cylinder 8 by the hexagonal screw 14 and the set screw 15 (the set screw 15 is a hexagonal tapered-end set screw), so that the support plate 13 and the third-stage piston rod 6 form an anti-rotation fit, further ensuring that the support plate 13 does not rotate.

[0040] The contact surface between the outer surface of the guide ring 11 and the support cylinder is made of copper. The mating surfaces between the outer surface of the cylinder body 3 and the inner support cylinder 9, the guide ring 11 and the inner surface of the inner support cylinder 9, and the outer surface of the inner support cylinder 9 and the inner surface of the outer support cylinder 8 are all designed with clearance fit. Through the wear-resistant properties of copper and the synergistic effect of multiple mating surfaces, when the AGV trolley generates off-center load during start-up and stop, each mating surface can disperse the off-center load, guiding the piston rod assembly to extend and retract in the correct direction, thus realizing the anti-off-center load and self-guiding function of the multi-stage hydraulic cylinder.

[0041] The guide sleeve 10 is fitted with a retaining ring 17, a shaft seal 18, an O-ring retainer 20, and an O-ring 21 at the mating point with the inner wall of the cylinder body 3, effectively preventing oil leakage. A piston seal 24 is fitted on the mating surface between the first-stage piston rod 4 and the cylinder body 3 to prevent internal oil leakage. A shaft guide band 19 is provided on the mating surface between the piston rod assembly and the guide sleeve 10, and a hole guide band 23 is provided on the mating surface between the cylinder body 3 and the first-stage piston rod 4, providing stable support and guidance. A dustproof ring 16 is fitted at the end of the guide sleeve 10 to prevent foreign objects from entering the cylinder body 3.

[0042] In this embodiment, the piston rod assembly adopts a three-stage nested structure, including the innermost third-stage piston rod 6, the middle second-stage piston rod 5, and the outermost first-stage piston rod 4. The three are coaxial and extend and retract relative to each other along the axial direction. The piston 7 is assembled at the end of the third-stage piston rod 6 and slides in cooperation with the inner wall of the second-stage piston rod 5.

[0043] Baffle 1 and baffle 2 are located at the axial connection points of the first-stage piston rod 4 and the second-stage piston rod 5, and the second-stage piston rod 5 and the third-stage piston rod 6, respectively. They are used to transmit axial force and limit piston stroke. That is, when the baffle extends, it transmits driving force to push the subsequent piston rods to extend in sequence, and when it retracts, it pushes the preceding piston rods to retract in sequence. At the same time, it plays a limiting role on the piston 7 and the second-stage piston rod 5 to ensure the orderly extension and retraction.

[0044] The following description, in conjunction with the application of the anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder, further illustrates this utility model: When the anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder is fixed on the AGV trolley, and hydraulic oil is injected, the piston rod extends and retracts. The piston rod drives the outer support cylinder 8 and the inner support cylinder 9 to extend and retract. The anti-rotation pin 26 slides along the anti-rotation groove of the cylinder body 3 and the inner support cylinder 9, restricting the relative rotation of the inner support cylinder 9 and the cylinder body 3. At the same time, the three-stage piston rod 6 is connected to the cylinder body through the connecting ring 12, the support plate 13, the outer support cylinder 8, and the inner support cylinder 9. The anti-rotation cooperation between the support plate 13 and the three-stage piston rod 6 further constrains the rotational freedom, achieving the anti-rotation effect.

[0045] During the movement of the AGV trolley, the trolley will have a large acceleration when starting and stopping, resulting in off-center load. Through the cooperation between the outer surface of the cylinder body 3 and the inner surface of the inner support cylinder 9, the cooperation between the guide ring 11 and the inner surface of the inner support cylinder 9, the cooperation between the outer surface of the inner support cylinder 9 and the inner surface of the outer support cylinder 8, the cooperation between the inner surface of the outer support cylinder 8 and the outer surface of the inner support cylinder 9, and the wear-resistant guiding effect of the copper contact surface, the off-center load force is dispersed and the piston rod assembly is guided to move axially, thereby achieving anti-off-center load and self-guidance, protecting the seals and each mating surface, and extending the service life of the hydraulic cylinder seals.

[0046] The foregoing description and accompanying drawings fully illustrate embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included or substituted for parts and features of other embodiments. Embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A self-guided, anti-eccentric load multi-stage hydraulic cylinder, characterized in that, It includes a cylinder body (3), a piston rod assembly, a piston (7), a guide sleeve (10), a guide ring (11), an inner support cylinder (9), and an outer support cylinder (8), all of which are arranged coaxially. The piston rod assembly is a three-stage nested structure, including the outermost first-stage piston rod (4), the second-stage piston rod (5) located in the middle, and the innermost third-stage piston rod (6), which are coaxial and extend and retract relative to each other along the axial direction; The piston (7) is axially fixed to the first end of the third-stage piston rod (6), and radially fits against the inner wall of the second-stage piston rod (5) to form a sliding fit. The piston at the end of the second-stage piston rod (5) radially fits against the inner wall of the first-stage piston rod (4) to form a sliding fit. The piston at the end of the first-stage piston rod (4) radially fits against the inner wall of the cylinder (3) to form a sliding fit. The inner support cylinder (9) is coaxially fitted on the outside of the cylinder body (3); the inner surface of the inner support cylinder (9) is machined with an anti-rotation groove that matches the outer surface of the cylinder body (3), forming a sliding channel to accommodate the anti-rotation pin (26); The outer support cylinder (8) is coaxially fitted on the outside of the inner support cylinder (9) and connected to the third-stage piston rod (6) through the connecting ring (12) and the support plate (13); the inner surface of the outer support cylinder (8) is machined with an anti-rotation groove that matches the outer surface of the inner support cylinder (9) to form a sliding channel for accommodating the anti-rotation pin (26); The guide sleeve (10) is coaxially press-fitted onto the inner wall of the first end of the cylinder body (3). The outer ring of the guide sleeve (10) is clearance-fitted with the inner wall of the cylinder body (3), and the inner ring is slidingly fitted with the outer wall of the first-stage piston rod (4). The guide ring (11) has a clearance fit between the outer ring and the inner wall of the inner support cylinder (9), and the inner ring is threaded to the outer surface of the cylinder body (3).

2. The anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder according to claim 1, characterized in that, It also includes fasteners, which include an internal hexagonal screw (14), a set screw one (15), and a set screw two (25). The set screw two (25) is used to prevent the anti-rotation pin (26) from coming out; The internal hex screw (14) and the set screw (15) work together to fix the connecting ring (12), the support plate (13), the outer support cylinder (8), and the three-stage piston rod (6).

3. The anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder according to claim 1, characterized in that, It also includes a sealing assembly, which includes a retaining ring (17), a shaft seal (18), an O-ring retaining ring (20), an O-ring one (21), an O-ring two (22), and a piston seal (24). The retaining ring (17), shaft seal (18), O-ring retaining ring (20), and O-ring one (21) are embedded in the circumferential groove of the guide sleeve (10) and located between the mating surface of the guide sleeve (10) and the inner wall of the cylinder (3) to prevent oil leakage. The piston seal (24) is fitted on the mating surface of the first-stage piston rod (4) and the cylinder (3) to prevent oil leakage.

4. The anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder according to claim 1, characterized in that, It also includes a guide support assembly, which includes a shaft guide strip (19) and a hole guide strip (23). The shaft guide belt (19) is fitted on the mating surface of the piston rod assembly and the guide sleeve (10), and the hole guide belt (23) is fitted on the mating surface of the cylinder (3) and the piston (7) to provide support and guidance during the extension and retraction of the piston rod assembly.

5. The anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder according to claim 1, characterized in that, It also includes a dustproof ring (16), which is fitted to the end of the guide sleeve (10) to prevent foreign objects from being brought into the cylinder (3).

6. The anti-rotation self-guided anti-eccentric load multi-stage hydraulic cylinder according to claim 1, characterized in that, It also includes baffle one (1) and baffle two (2), which are located at the axial connection of the first-stage piston rod (4) and the second-stage piston rod (5) and the axial connection of the second-stage piston rod (5) and the third-stage piston rod (6), respectively, to realize the transmission of axial force and limit the piston stroke.

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