Hydraulic cylinder with locking function in fully retracted state

Abstract

The utility model discloses a kind of hydraulic cylinders with locking function in full shrink state, comprising: cylinder, guiding sleeve connected to the end of cylinder body, piston rod arranged in cylinder body, the end of the piston rod passes through the guiding sleeve and extends out of cylinder body, the end of the guiding sleeve one end of cylinder body is fixedly connected with cover, the end of the piston rod extending out of cylinder body is connected with connecting block, locking structure is arranged in the outer circumferential groove of connecting block, the end of the cover is provided with the protrusion that can be used for limiting the locking structure.The utility model realizes the locking function of hydraulic cylinder under full shrink state by the cooperation of pin shaft and protrusion, simple structure, easy to operate, can effectively prevent hydraulic cylinder from accidentally extending out due to external force under full shrink state, improve the use safety.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic cylinder technology, specifically to a hydraulic cylinder with a locking function in its fully retracted state. Background Technology

[0002] Hydraulic cylinders are common hydraulic actuators widely used in engineering machinery, agricultural machinery, mining machinery, and other fields. In practical applications, the piston rod of a hydraulic cylinder needs to retract completely after completing its work. However, for hydraulic cylinders with the piston rod head installed vertically downwards, when the equipment finishes working and the piston rod retracts, the hydraulic system of the equipment is shut down, and the hydraulic lock is engaged. Due to internal leakage in the hydraulic lock, if the piston rod has a large weight, it will gradually fall and extend under the action of gravity, which not only creates a safety hazard but also hinders the debugging and maintenance of the equipment when it is restarted.

[0003] Most existing systems use a built-in steel ball locking structure, which is not only complex in structure and has many parts, but also difficult to design and has high processing costs, making it unsuitable for large-scale production and application. Utility Model Content

[0004] To simplify installation and improve efficiency, this invention provides a hydraulic cylinder with a locking function in its fully retracted state, solving the aforementioned technical problems. The technical solution of this invention is as follows:

[0005] A hydraulic cylinder with a locking function in its fully retracted state includes: a cylinder body, a guide sleeve connected to the end of the cylinder body, a piston rod disposed in the cylinder body, one end of the piston rod extending out of the cylinder body through the guide sleeve, a cover fixedly connected to the end of the cylinder body near the guide sleeve, a connecting block connected to the end of the piston rod extending out of the cylinder body, a locking structure provided in a groove on the outer circumferential surface of the connecting block, and a protrusion at the end of the cover for limiting the locking structure.

[0006] Furthermore, the locking structure includes: a pin, a first nut, a spring, and a spring base. The pin has a stepped portion, the first nut is fixed at the opening of the groove, the pin is movably connected to the first nut, the top end of the pin extends out of the upper end face of the first nut, the spring base is located at the bottom of the groove, and the spring is located between the pin and the spring base, with one end abutting against the spring base and the other end abutting against the stepped portion at the bottom end of the pin.

[0007] Furthermore, the protrusion cooperates with the pin to achieve a limiting position.

[0008] Furthermore, the inner side of the protrusion is provided with a first inclined surface. When the piston rod is not fully retracted, the pin is located on the outer side of the protrusion; when the piston rod is fully retracted, the pin is located on the inner side of the first inclined surface. The first inclined surface cooperates with the top of the pin to achieve a limiting position.

[0009] Furthermore, a second inclined surface is provided on the outer side of the protrusion.

[0010] Furthermore, the connecting block and the piston rod are connected by a connecting structure, one end of which is fixed inside the piston rod and the other end of which is fixed inside the connecting block.

[0011] Furthermore, the connection structure includes: a connecting rod, a second nut, a third nut, a pressure cap, and a fourth nut. The second nut is threaded into the inner hole of the piston rod. One end of the connecting rod passes through the second nut and is fixed in the inner hole of the piston rod by the third nut. The other end of the connecting rod passes through the through hole of the connecting block and is fixed in the through hole of the connecting block by the pressure cap and the fourth nut.

[0012] Furthermore, the mating surface between the piston rod and the connecting block is a spherical surface.

[0013] Furthermore, a ball seat is provided between the second nut and the third nut.

[0014] Furthermore, a pressure plate is connected to the end face of the connecting block on the side away from the piston rod.

[0015] The beneficial effects of this utility model are as follows:

[0016] 1. The piston rod is locked in its fully retracted state by means of a locking structure and a protrusion. The structure is simple, easy to maintain and low in cost.

[0017] 2. The locking structure consists of a pin, a first nut, a spring, and a spring base. It utilizes elastic force to move the pin, thereby achieving locking. The structure is simple. Furthermore, the spring's pre-compression can be adjusted to regulate the pin's release force, allowing the locking structure to be adjusted according to different work requirements, thus improving adaptability and flexibility.

[0018] 3. The inner and outer sides of the protrusion are both beveled, which makes the contact between the pin and the protrusion smoother, reduces wear, and extends the service life of the locking structure.

[0019] 4. The connecting structure ensures a reliable connection between the piston rod and the connecting block. Furthermore, the spherical design of the mating surface between the piston rod and the connecting block allows for a certain degree of deflection, reducing the impact of lateral forces on the hydraulic cylinder, extending its service life, and enhancing the stability of the connection. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the hydraulic cylinder with locking function according to this utility model.

[0021] Figure 2 This is a schematic diagram of the piston rod before locking according to this utility model;

[0022] Figure 3 This is a schematic diagram of the piston rod in the locked state of this utility model.

[0023] Figure 4 This is a schematic diagram of the connection structure of this utility model;

[0024] In the diagram: 1. Cylinder block; 2. Piston rod; 3. Guide sleeve;

[0025] 4. Cover; 41. Protrusion; 411. First inclined surface; 412. Second inclined surface;

[0026] 5. Connecting block;

[0027] 6. Locking structure; 61. Pin; 62. First nut; 63. Spring; 64. Spring seat;

[0028] 7. Connecting structure; 71. Connecting rod; 72. Second nut; 73. Third nut; 74. Pressure cap; 75. Fourth nut; 76. Ball seat;

[0029] 8. Pressure plate. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0031] like Figures 1 to 4This embodiment provides a hydraulic cylinder with a locking function in its fully retracted state, including a cylinder body 1, a guide sleeve 3 connected to the end of the cylinder body 1, and a piston rod 2 disposed inside the cylinder body 1. One end of the piston rod 2 passes through the guide sleeve 3 and extends out of the cylinder body 1. A cover 4 is fixedly connected to the end of the cylinder body 1 near the guide sleeve 3. A connecting block 5 is connected to the end of the piston rod 2 extending out of the cylinder body 1. The connecting block 5 is coaxially arranged with the piston rod 2. A groove is machined on the outer circumferential surface of the connecting block 5 extending towards the axis. A locking structure 6 is installed in the groove of the connecting block 5. Preferably, there can be multiple grooves, and the number of locking structures 6 is adapted to the number of grooves. The end of the cover 4 away from the cylinder body 1 is provided with a protrusion 41 for limiting the locking structure 6.

[0032] In this embodiment, the cover 4 is fixedly connected to the end of the cylinder 1 by screws.

[0033] As another option in this embodiment, the cylinder body 1 and the cover 4 are connected by a flange, and a sealing ring is used to ensure the sealing of the connection. This design makes the connection between the cover 4 and the cylinder body 1 more robust and reliable, while also facilitating disassembly and maintenance.

[0034] The locking structure 6 includes a pin 61, a first nut 62, a spring 63, and a spring base 64. The first nut 62 is fixed at the opening of the groove, the pin 61 is movably connected to the first nut 62, the spring base 64 is located at the bottom of the groove, and the spring 63 is located between the pin 61 and the spring base 64, with one end abutting against the spring base 64 and the other end abutting against the bottom end of the pin 61. Under the action of elastic force, the top end of the pin 61 extends out of the upper surface of the first nut 62.

[0035] In this embodiment, the pin 61 is elongated and has a circumferentially protruding stepped portion. The upper end face of the stepped portion abuts against the first nut 62 to prevent the pin 61 from coming out. One end of the spring 63 abuts against the spring base 64, and the other end abuts against the lower end face of the stepped portion of the pin 61.

[0036] As another option in this embodiment, the spring base 64 can be designed to be adjustable. By adjusting the screw, the pre-compression of the spring 63 can be changed, thereby adjusting the pop-out force of the pin 61. This design allows the locking structure to be adjusted according to different working requirements, improving adaptability and flexibility.

[0037] The top surface of the pin 61 is higher than the inner wall surface of the protrusion 41, so that the hydraulic cylinder can be locked by the cooperation between the protrusion 41 and the pin 61. The inner side of the protrusion 41 near the cylinder body 1 is provided with a first inclined surface 411, and the outer side of the protrusion 41 away from the cylinder body 1 is provided with a second inclined surface 412. When the piston rod 2 is not fully retracted, the pin 61 is located outside the protrusion 41. When the piston rod 2 is fully retracted, the pin 61 is located inside the first inclined surface 411. The first inclined surface 411 cooperates with the top of the pin 61 to achieve mechanical limiting.

[0038] In this embodiment, when the piston rod 2 retracts, the pin 61 is pressed down by the second inclined surface 412, overcoming the elastic force of the spring 63, and follows the movement of the piston rod 2 into the inner side of the protrusion 41. The first inclined surface 411 forms a mechanical limit on the pin 61 to prevent the piston rod 2 from loosening under the action of gravity.

[0039] As a preferred embodiment, the second inclined surface 412 on the outer side of the protrusion 41 has an inclination angle of 45 degrees. This design allows the pin 61 to slide more smoothly when it contacts the second inclined surface 412, reducing frictional resistance and improving operational stability.

[0040] The inner and outer sides of the protrusion 41 are sloped, which helps to guide the pin 61, making the piston rod 2 run smoothly and preventing obstruction when the protrusion 41 presses against the pin 61. Preferably, the top of the pin 61 is provided with a slope that matches the first slope 411 and the second slope 412.

[0041] As another option in this embodiment, the top of the pin 61 is a hemispherical structure. This design makes the pin 61 contact the first inclined surface 411 and the second inclined surface 412 of the protrusion 41 more smoothly, reduces wear, and extends the service life of the locking structure.

[0042] The connecting block 5 is connected to the piston rod 2 through the connecting structure 7. One end of the connecting structure 7 is fixed inside the piston rod 2, and the other end is fixed inside the connecting block 5.

[0043] In this embodiment, the connecting structure 7 includes a connecting rod 71, a second nut 72, a third nut 73, a pressure cap 74, and a fourth nut 75. The piston rod 2 and the connecting block 5 are connected at an axial distance with an inner hole containing an internal thread. The connecting block 5 has a through hole coaxial with the inner hole. The second nut 72 is threaded into the inner hole of the piston rod 2. One end of the connecting rod 71 passes through the second nut 72 and is fixed within the inner hole of the piston rod 2 by the third nut 73. The other end of the connecting rod 71 passes through the through hole of the connecting block 5 and is fixed within the through hole of the connecting block 5 by the pressure cap 74 and the fourth nut 75. As a preferred embodiment, the mating surface between the piston rod 2 and the connecting block 5 is a spherical surface, and a ball seat 76 is also provided between the second nut 72 and the third nut 73.

[0044] The design of the connecting structure 7 ensures a reliable connection between the piston rod 2 and the connecting block 5. At the same time, since the mating surface between the piston rod 2 and the connecting block 5 is spherical, it allows for a certain angle of deflection, reducing the impact of lateral forces on the hydraulic cylinder and extending the service life of the hydraulic cylinder. The ball seat 76 further enhances the stability of the connection.

[0045] A pressure plate 8 is fixedly connected to the end face of the connecting block 5 away from the piston rod 2. The pressure plate 8 not only protects the connecting structure 7, but also makes it easier for the connecting block 5 to be connected to external equipment, thus expanding the application range of the hydraulic cylinder.

[0046] When the hydraulic cylinder in this embodiment is working, when the hydraulic cylinder is in the extended state, the piston rod 2 extends out from the cylinder body 1, and there is a certain distance between the connecting block 5 and the cover 4. The pin 61 is located outside the protrusion 41. When the hydraulic cylinder needs to retract, the piston rod 2 retracts into the cylinder body 1, and the connecting block 5 gradually approaches the cover 4. The pin 61 installed on the connecting block 5 will contact the protrusion 41 on the cover 4. Since the protrusion 41 has a second inclined surface 412 on its outer side, when the pin 61 contacts the second inclined surface 412, it will slide along the second inclined surface 412 and be pressed into the groove of the connecting block 5, overcoming the elastic force of the spring 63. When the pin 61 completely passes the protrusion 41, under the action of the spring 63, the pin 61 will pop out and be located inside the protrusion 41, abutting against the first inclined surface 411, thereby achieving mechanical locking.

[0047] At this point, even if the hydraulic system loses pressure, the piston rod 2 will not extend on its own. The pin 61 and the first inclined surface 411 of the protrusion 41 form a mechanical lock, and the locking structure can withstand the weight of the piston rod without loosening. This locking structure is simple in design and compact in structure, and can effectively prevent the hydraulic cylinder from accidentally extending due to system pressure loss in the fully retracted state, thus improving the safety and reliability of the equipment.

[0048] When it is necessary to release the lock, simply apply sufficient hydraulic pressure to the hydraulic cylinder to generate sufficient thrust on the piston rod 2. The pin 61 will slide along the first inclined surface 411 and be pressed into the groove of the connecting block 5, thereby enabling the piston rod 2 to extend normally.

[0049] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined by the scope of the claims.

Claims

1. A hydraulic cylinder with a locking function in its fully retracted state, comprising: A cylinder body (1), a guide sleeve (3) connected to the end of the cylinder body (1), and a piston rod (2) disposed inside the cylinder body (1). One end of the piston rod (2) passes through the guide sleeve (3) and extends out of the cylinder body (1). The cylinder body (1) is characterized by having a cover (4) fixedly connected to the end of the cylinder body (1) near the end of the guide sleeve (3), and a connecting block (5) connected to the end of the piston rod (2) extending out of the cylinder body (1). A locking structure (6) is provided in the groove on the outer circumferential surface of the connecting block (5), and a protrusion (41) is provided at the end of the cover (4) for limiting the locking structure (6).

2. A hydraulic cylinder with a locking function in its fully retracted state according to claim 1, characterized in that, The locking structure (6) includes: a pin (61), a first nut (62), a spring (63), and a spring base (64). The pin (61) has a stepped portion. The first nut (62) is fixed at the opening of the groove. The pin (61) is movably connected to the first nut (62). The top end of the pin (61) extends out of the upper end face of the first nut (62). The spring base (64) is located at the bottom of the groove. The spring (63) is located between the pin (61) and the spring base (64), with one end abutting against the spring base (64) and the other end abutting against the stepped portion at the bottom end of the pin (61).

3. A hydraulic cylinder with a locking function in its fully retracted state according to claim 2, characterized in that, The protrusion (41) cooperates with the pin (61) to achieve a limiting position.

4. A hydraulic cylinder with a locking function in its fully retracted state according to claim 3, characterized in that, The inner side of the protrusion (41) is provided with a first inclined surface (411). When the piston rod (2) is not fully retracted, the pin (61) is located outside the protrusion (41); when the piston rod (2) is fully retracted, the pin (61) is located inside the first inclined surface (411). The first inclined surface (411) cooperates with the top of the pin (61) to achieve a limiting position.

5. A hydraulic cylinder with a locking function in its fully retracted state according to claim 4, characterized in that, The outer side of the protrusion (41) is provided with a second inclined surface (412).

6. A hydraulic cylinder with a locking function in its fully retracted state according to claim 1, characterized in that, The connecting block (5) is connected to the piston rod (2) by a connecting structure (7), one end of the connecting structure (7) is fixed inside the piston rod (2), and the other end is fixed inside the connecting block (5).

7. A hydraulic cylinder with a locking function in its fully retracted state according to claim 6, characterized in that, The connecting structure (7) includes: a connecting rod (71), a second nut (72), a third nut (73), a pressure cap (74), and a fourth nut (75). The second nut (72) is threaded into the inner hole of the piston rod (2). One end of the connecting rod (71) passes through the second nut (72) and is fixed in the inner hole of the piston rod (2) by the third nut (73). The other end of the connecting rod (71) passes through the through hole of the connecting block (5) and is fixed in the through hole of the connecting block (5) by the pressure cap (74) and the fourth nut (75).

8. A hydraulic cylinder with a locking function in its fully retracted state according to claim 7, characterized in that, The mating surface between the piston rod (2) and the connecting block (5) is a spherical surface.

9. A hydraulic cylinder with a locking function in its fully retracted state according to claim 7, characterized in that, A ball seat (76) is provided between the second nut (72) and the third nut (73).

10. A hydraulic cylinder with a locking function in its fully retracted state according to claim 1, characterized in that, The end face of the connecting block (5) away from the piston rod (2) is connected to a pressure plate (8).

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