A self-locking hydraulic cylinder

Abstract

The present invention proposes a self-locking hydraulic cylinder for lifting, comprising: a main cylinder with oil ports A and B and a first piston assembly, a secondary cylinder with oil ports C and D and a second piston assembly, an oil circuit, the first piston assembly comprising a first piston and a first piston rod, the second piston assembly comprising a second piston and a second piston rod, wherein: the secondary cylinder is located at one side of the first ejection end and is fixed to the main cylinder; the secondary cylinder is also provided with an air port; the first piston rod is provided with a locking groove; the second piston rod is provided with a locking block elastically connected thereto, the locking block being located in the locking groove; the oil port A comprises a main oil port and a secondary oil port; the oil port C is connected to the secondary oil port via a pipeline (17), a first non-return valve is provided between the oil port C and the secondary oil port; the oil circuit comprises a main oil circuit connecting the main oil port and the oil port B, and a branch circuit connecting the oil port D and the main oil circuit, a second non-return valve is provided at the junction of the main oil port and the main oil circuit. The present invention can be self-locking without manually moving a latch or a pad.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic cylinders, and in particular to a lifting self-locking hydraulic cylinder. Background Art

[0002] Self-locking hydraulic cylinders are widely needed in the engineering field. For example, in the mechanical field of many lifting equipment such as metallurgy, coal mining, engineering machinery, sanitation vehicles, etc., the hydraulic components need to lock the hydraulic cylinder to prevent the workpiece from being displaced under the action of external force or deadweight (hydraulic cylinder upright) when it stops working. At present, there are several main methods for locking the hydraulic cylinder piston rod: one is to use a hydraulic lock in the hydraulic system to prevent the flow of hydraulic oil to lock the hydraulic cylinder piston rod; this locking method has obvious disadvantages: the internal leakage of the hydraulic cylinder barrel and the hydraulic lock makes it difficult for the hydraulic cylinder piston rod to be locked. The second is to use a latch mechanism or a pad to fix the piston rod. This locking method requires manual movement of the latch or pad. Summary of the invention

[0003] In order to solve the technical problems existing in the background technology, the present invention proposes a lifting self-locking hydraulic cylinder.

[0004] The present invention provides a self-locking hydraulic cylinder for lifting, comprising: a main cylinder with oil ports A and B and a first piston assembly installed in the main cylinder, a secondary cylinder with oil ports C and D and a second piston assembly installed in the secondary cylinder, and an oil circuit for conveying hydraulic oil, wherein the first piston assembly comprises a first piston located between the oil ports A and B and a first piston rod connected to the first piston, the second piston assembly comprises a second piston located on a side of the oil port D close to the oil port C and a second piston rod connected to the second piston, and one end of the first piston rod is located outside the main cylinder to form a first ejection end, and one end of the second piston rod is located outside the main cylinder to form a second ejection end, wherein:

[0005] The auxiliary cylinder is located at one side of the first ejection end and is fixed to the main cylinder, and the second ejection end faces the first piston rod; the auxiliary cylinder is also provided with an air port, and the air port is located at an end away from the second ejection end;

[0006] The first piston rod is provided with a plurality of locking grooves arranged in sequence along the length direction thereof, and a side wall of the locking groove close to the first piston is an inclined surface inclined toward the first piston;

[0007] The second ejection end of the second piston rod is provided with a locking block elastically connected thereto, the locking block having an inclined surface, the locking block being located in the locking groove, and the inclined surface thereof being in contact with the inclined surface of the locking groove;

[0008] The oil port A is located on a side of the oil port B close to the first ejection end, and the oil port A includes a main oil port and a secondary oil port;

[0009] The oil port C is located between the two ends of the auxiliary cylinder barrel, the oil port C is connected to the auxiliary oil port via a pipeline (17), and a first one-way valve is provided between the oil port C and the auxiliary oil port to allow the hydraulic oil to flow in one direction toward the auxiliary oil port; the oil port D is located on a side of the oil port C close to the second ejection end;

[0010] The oil circuit includes a main oil circuit connecting the main oil port and the oil port B, and a branch circuit connecting the oil port D and the main oil circuit. A second one-way valve 1 (0) is provided at the junction of the main oil port and the main oil circuit to allow the hydraulic oil to flow in one direction toward the oil port B.

[0011] Preferably, a drain port is provided at the bottom of the locking groove, and a drain port is provided on the side wall of the first piston rod away from the locking groove, and the drain port is located at one end close to the first piston; a flow channel connecting each drain port is provided in the first piston rod.

[0012] Preferably, the second piston rod has a guide channel extending from its second end to its other end, and an elastic element and a guide rod arranged in the elastic channel, one end of the guide rod abuts against the elastic element, and the other end is located outside the guide channel; the locking block is fixedly connected to the guide rod.

[0013] Preferably, the elastic element comprises a spring.

[0014] Preferably, the ejection end of the main cylinder is provided with a mounting seat detachably fixed thereto, and the auxiliary cylinder is fixedly mounted on the mounting seat.

[0015] Preferably, the mounting seat includes a sleeve and a support portion fixedly mounted on the sleeve, the sleeve is sleeved on the main cylinder and threadedly matched with the main cylinder, the support portion is located on one side of the sleeve close to the top end of the main cylinder; the auxiliary cylinder is fixedly mounted on the support portion.

[0016] Preferably, a mounting block is provided on the side wall of the main cylinder, and a mounting hole is provided on the mounting block.

[0017] In the present invention, a secondary cylinder is provided at the ejection end of the main cylinder, a locking groove is provided on the first piston rod, and the side wall of the locking groove close to the first piston is an inclined surface inclined toward the first piston; a locking block with an inclined surface is provided at the end of the second piston rod, and the locking block is located in the locking groove, and the inclined surface of the locking groove is in contact with the inclined surface of the locking groove; at the same time, the oil port A is located on the side close to the ejection end of the main cylinder, and the oil port A includes the main oil port and the secondary oil port; the secondary cylinder is away from its ejection end One end of the auxiliary cylinder is provided with an air port, the oil port C on the auxiliary cylinder is located between the two ends of the auxiliary cylinder and is connected to the auxiliary oil port through a pipeline, and a first one-way valve is set between the oil port C and the auxiliary oil port to allow the hydraulic oil to flow in one direction to the auxiliary oil port; the oil port D is located on the side of the oil port C close to the top end of the auxiliary cylinder, the oil circuit includes a main oil circuit connecting the main oil port and the oil port B, and a branch connecting the oil port D and the main oil circuit, and a second one-way valve is set at the junction of the main oil port and the main oil circuit to allow the hydraulic oil to flow in one direction to the oil port B. Thus, the purpose of automatic locking can be achieved without manually moving the latch or pad. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a schematic structural diagram of a jacking self-locking hydraulic cylinder.

[0019] Figure 2 for Figure 1 A partial enlarged view of

[0020] Figure 3 The present invention provides a schematic structural diagram of the auxiliary cylinder in the jacking self-locking hydraulic cylinder.

[0021] Figure 4 This is a schematic diagram of the flow direction of hydraulic oil during the lifting process of the first piston rod in a lifting self-locking hydraulic cylinder proposed by the present invention.

[0022] Figure 5 This is a schematic diagram of the flow direction of hydraulic oil during the retraction process of the first piston rod in a jacking self-locking hydraulic cylinder proposed by the present invention. DETAILED DESCRIPTION

[0023] Reference Figure 1-3The present invention proposes a self-locking hydraulic cylinder for lifting, comprising: a main cylinder 1 with oil ports A5 and B6 and a first piston assembly installed in the main cylinder 1, a secondary cylinder 3 with oil ports C7 and D8 and a second piston assembly installed in the secondary cylinder 3, and an oil circuit 9 for conveying hydraulic oil, the first piston assembly comprising a first piston located between the oil ports A5 and B and a first piston rod 2 connected to the first piston, the second piston assembly comprising a second piston located on a side of the oil port D8 close to the oil port C7 and a second piston rod 4 connected to the second piston, and one end of the first piston rod 2 is located outside the main cylinder 1 to form a first ejection end, and one end of the second piston rod 4 is located outside the secondary cylinder 3 to form a second ejection end, wherein:

[0024] The auxiliary cylinder 3 is located on one side of the first ejection end and is fixed to the main cylinder 1, and the second ejection end faces the first piston rod 2; the auxiliary cylinder 3 is also provided with an air port, and the air port is located at the end away from the second ejection end. The first piston rod 2 is provided with a plurality of locking grooves 11 arranged in sequence along its length direction, and the side wall of the locking groove 11 close to the first piston side is an inclined surface inclined toward the first piston. The second ejection end of the second piston rod 4 is provided with a locking block 12 elastically connected thereto, and the locking block 12 has an inclined surface. The locking block 12 is located in the locking groove 11, and its inclined surface fits with the inclined surface of the locking groove 11, so that the locking block 12 can pass over the locking groove 11 along the inclined surface as the first piston rod 2 is lifted, and will not interfere with the lifting action of the first piston rod 2, but can prevent the first piston rod 2 from retreating and retracting in the lifted state, so as to achieve the purpose of self-locking.

[0025] The oil port A5 is located on a side close to the first ejection end, and the oil port A5 includes a main oil port 51 and an auxiliary oil port 52. The oil port C7 is located between the two ends of the auxiliary cylinder 3, and the oil port C7 is connected to the auxiliary oil port 52 via a pipeline 17. A first check valve 18 is provided between the oil port C7 and the auxiliary oil port 52 to allow the hydraulic oil to flow in one direction toward the auxiliary oil port 52, so that the hydraulic oil cannot flow back to the oil port C7.

[0026] The oil port D8 is located on the side close to the second ejection end; the oil circuit 9 includes a main oil circuit 91 connecting the main oil port 51 and the oil port B6, and a branch circuit 92 connecting the oil port D8 and the main oil circuit 91. A second one-way valve 10 is provided at the junction of the main oil port 51 and the main oil circuit 91 to allow the hydraulic oil to flow in one direction to the oil port B6. When the hydraulic oil flows from the oil port B to the oil port A, it can only flow from the main oil circuit 91 to the branch circuit 92 and finally enter the auxiliary cylinder 3 from the oil port D, and then flow into the main cylinder 2 from the oil port C and the auxiliary oil port 52.

[0027] When the first piston rod 2 needs to retract, the hydraulic oil in the main cylinder 1 can only enter the auxiliary cylinder 3 from the oil port D8 first to push the second piston to move toward the oil port C7, so that the locking block 12 disengages from the locking groove 11 to enter the unlocked state. At this time, the first piston rod 2 can retract freely. With the entry of hydraulic oil, when the second piston is pushed to the side of the oil port C7 away from the oil port D8, the hydraulic oil enters the main cylinder 1 through the oil port C7 again to push the first piston rod 2 to retract.

[0028] Reference Figure 4-5 The specific working principle is as follows: during the lifting process of the first piston rod 2, the locking block 12 passes over the locking groove 11 along the inclined surface as the first piston rod 2 is lifted, and will not interfere with the lifting action of the first piston rod 2, but will hinder the retraction of the first piston rod 2, thereby achieving the purpose of self-locking. During the retraction process of the first piston rod 2, the hydraulic oil in the main cylinder 1 can only enter the auxiliary cylinder 3 from the oil port D8 first to push the second piston to move toward the oil port C7, so that the locking block 12 is released from the locking groove 11, that is, unlocked. At this time, the first piston rod 2 can be freely retracted. When the second piston is pushed to the side of the oil port C7 away from the oil port D8, the hydraulic oil enters the main cylinder 1 through the oil port C7 to push the first piston rod 2 to retract. When the first piston rod 2 is lifted again, the hydraulic oil in the auxiliary cylinder 2 flows from the oil port D8 to the oil port B6 to enter the emptying state, and the hydraulic oil in the main cylinder 1 can only flow from the main oil port 51 to the oil port B6 to provide power for the lifting work.

[0029] As can be seen from the above, the present invention can achieve the purpose of automatic locking without manual movement of the latch or the pad.

[0030] In addition, in this embodiment, the second piston rod 4 has a guide channel extending from its second ejection end to its other end, and an elastic element 13 and a guide rod 14 arranged in the elastic channel, one end of the guide rod 14 abuts against the elastic element 13, and the other end of the guide rod 14 is located outside the guide channel; the locking block 12 is fixedly connected to the guide rod 14 to achieve an elastic connection between the locking block 12 and the second piston rod 4. Specifically, the elastic element 13 includes a spring.

[0031] In this embodiment, the ejection end of the main cylinder 1 is provided with a mounting seat 15 which is detachably fixed thereto, and the auxiliary cylinder 3 is fixedly mounted on the mounting seat 15. Specifically: the mounting seat 15 includes a sleeve and a support portion fixedly mounted on the sleeve, the sleeve is sleeved on the main cylinder 1 and threadedly matched with the main cylinder 1, and the support portion is located on the side of the sleeve close to the ejection end of the main cylinder 1; the auxiliary cylinder 3 is fixedly mounted on the support portion, and the threaded matching method is convenient for quick disassembly and assembly.

[0032] In this embodiment, a mounting block 16 is provided on the side wall of the main cylinder 1. The mounting block 16 is provided with an assembly hole so that the hydraulic cylinder can be fixed on other equipment by using the mounting block 16.

[0033] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A self-locking hydraulic cylinder for lifting, characterized in that: include: A main cylinder (1) with oil ports A (5) and B (6) and a first piston assembly installed in the main cylinder (1), a secondary cylinder (3) with oil ports C (7) and D (8) and a second piston assembly installed in the secondary cylinder (3), and an oil circuit (9) for conveying hydraulic oil; the first piston assembly comprises a first piston located between the oil ports A (5) and B and a first piston rod (2) connected to the first piston, the second piston assembly comprises a second piston located on the side of the oil port D (8) close to the oil port C (7) and a second piston rod (4) connected to the second piston, one end of the first piston rod (2) is located outside the main cylinder (1) to form a first ejection end, and one end of the second piston rod (4) is located outside the secondary cylinder (3) to form a second ejection end, wherein: The auxiliary cylinder (3) is located on one side of the first ejection end and is fixed to the main cylinder (1), and the second ejection end faces the first piston rod (2); the auxiliary cylinder (3) is also provided with an air port, and the air port is located at an end away from the second ejection end; the first piston rod (2) is provided with a plurality of locking grooves (11) arranged in sequence along its length direction, and the side wall of the locking groove (11) close to the first piston is an inclined surface inclined toward the first piston; the second ejection end of the second piston rod (4) is provided with a locking block (12) elastically connected thereto, the locking block (12) has an inclined surface, the locking block (12) is located in the locking groove (11), and its inclined surface is in contact with the inclined surface of the locking groove (11); The oil port A (5) is located on a side close to the first ejection end, and the oil port A (5) includes a main oil port (51) and an auxiliary oil port (52); the oil port C (7) is located between the two ends of the auxiliary cylinder (3), the oil port C (7) is connected to the auxiliary oil port (52) via a pipeline (17), and a first check valve (18) is provided between the oil port C (7) and the auxiliary oil port (52) to enable the hydraulic oil to flow in one direction toward the auxiliary oil port (52); the oil port D (8) is located on a side close to the second ejection end of the oil port C (7); the oil circuit (9) includes a main oil circuit (91) connecting the main oil port (51) and the oil port B (6), and a branch circuit (92) connecting the oil port D (8) and the main oil circuit (91), and a second check valve (10) is provided at the junction of the main oil port (51) and the main oil circuit (91) to enable the hydraulic oil to flow in one direction toward the oil port B (6).

2. The self-locking hydraulic cylinder for lifting according to claim 1, characterized in that: The second piston rod (4) has a guide channel extending from its second ejection end to its other end, and an elastic element (13) and a guide rod (14) arranged in the elastic channel, one end of the guide rod (14) abuts against the elastic element (13), and the other end of the guide rod (14) is located outside the guide channel; the locking block (12) is fixedly connected to the guide rod (14).

3. The self-locking hydraulic cylinder for lifting according to claim 2 is characterized in that: The elastic element (13) comprises a spring.

4. The self-locking hydraulic cylinder for lifting according to claim 1, characterized in that: The ejection end of the main cylinder (1) is provided with a mounting seat (15) which is detachably fixed thereto, and the auxiliary cylinder (3) is fixedly mounted on the mounting seat (15).

5. The self-locking hydraulic cylinder for lifting according to claim 4, characterized in that: The mounting seat (15) comprises a sleeve and a support portion fixedly mounted on the sleeve. The sleeve is sleeved on the main cylinder (1) and threadedly matched with the main cylinder (1). The support portion is located on a side of the sleeve close to the ejection end of the main cylinder (1). The auxiliary cylinder (3) is fixedly mounted on the support portion.

6. The self-locking hydraulic cylinder for lifting according to any one of claims 1 to 5, characterized in that: A mounting block (16) is provided on the side wall of the main cylinder (1), and an assembly hole is provided on the mounting block (16).

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