Overpressure self-elevating hydraulic cylinder

Abstract

The utility model relates to an overpressure self-elevating hydraulic cylinder, and belongs to the field of hydraulic equipment. According to the technical scheme, the hydraulic cylinder comprises a hydraulic cylinder body, a hollow piston rod, a piston 9 and a reset spring 8, the hollow piston rod is arranged in the hydraulic cylinder body, a hole is formed in the end of the hydraulic cylinder body, one end of the hollow piston rod extends out of the hole, and the piston is arranged at the other end of the hollow piston rod and makes contact with the inner wall of the hydraulic cylinder body; and the end part of the hollow piston rod extending out of the hydraulic cylinder body is a hydraulic outlet connected with a liquid return pipe. Operation of the hydraulic cylinder is achieved through a special mechanical structure and liquid supply pressure, and power is provided for overpressure monitoring or overpressure movement.

Description

Technical Field

[0001] The invention relates to an overpressure self-lifting hydraulic cylinder and belongs to the field of hydraulic equipment. Background Art

[0002] The hydraulic cylinder is a common power device that realizes hydraulic power output by circulating high-pressure hydraulic pressure in the hydraulic cylinder to push the piston rod to extend and retract.

[0003] The output of the hydraulic cylinder is achieved through high-pressure hydraulic oil, and its input requires the hydraulic station's hydraulic pump to start and stop to realize the delivery of hydraulic oil. However, the hydraulic pump and motor that are repeatedly started and stopped are prone to overload at the moment of starting, causing damage to the motor.

[0004] For the pressure change of the hydraulic station, a pressure gauge is currently used. For some environments, overpressure detection is required. How to warn of overpressure currently requires a sensor device. Summary of the Invention

[0005] The utility model provides an overpressure self-lifting hydraulic cylinder, which can realize the movement of the hydraulic cylinder piston by checking whether the pressure of the hydraulic cylinder liquid inlet exceeds the design value, thereby meeting some movement requirements under overpressure.

[0006] The technical solution adopted in the present invention is:

[0007] The utility model of the super-pressure self-lifting hydraulic cylinder includes a hydraulic cylinder body, a hollow piston rod, a piston 9 and a return spring 8. The hollow piston rod is arranged in the hydraulic cylinder body, and a hole is opened at the end of the hydraulic cylinder body. One end of the hollow piston rod extends out of the hole, and a piston is arranged at the other end to contact the inner wall of the hydraulic cylinder.

[0008] The end of the hollow piston rod extending out of the hydraulic cylinder body is a hydraulic outlet connected to the liquid return pipe;

[0009] The piston end of the hydraulic cylinder body is opened as a hydraulic inlet, which is connected to the hydraulic high-pressure oil pipe. A return spring is sleeved on the outside of the hollow piston rod. One end of the return spring is connected to the inner side of the opening of the hydraulic cylinder body for a circle, and the other end is connected to the upper side of the piston.

[0010] According to the overpressure self-lifting hydraulic cylinder, a sleeve is provided on the outside of the piston rod, and the sleeve isolates the return spring from the outer side surface of the hollow piston rod.

[0011] According to the overpressure self-lifting hydraulic cylinder, the length of the casing is 1 / 3 to 1 / 2 of the length of the piston rod.

[0012] According to the overpressure self-lifting hydraulic cylinder, a hydraulic cylinder flange is provided around the opening end of the hydraulic cylinder, and the hydraulic cylinder flange is fixed to the hydraulic cylinder mounting plate by bolts, and the hydraulic cylinder mounting plate is provided with mounting through holes.

[0013] According to the overpressure self-lifting hydraulic cylinder, the hydraulic high-pressure oil pipe connected to the hydraulic inlet is laid outside the hydraulic cylinder body, and a liquid inlet connection port is provided at the protruding end of the piston rod.

[0014] When the pressure at the hydraulic cylinder's inlet is less than or equal to the minimum self-lifting pressure, the piston does not move. When the pressure at the hydraulic cylinder's inlet exceeds the minimum self-lifting pressure, the piston drives the hollow piston rod to extend. Pressure and extension length are linearly proportional, with greater pressure resulting in longer extension. As pressure increases, the hollow piston rod reaches its limit after reaching the maximum self-lifting pressure, and the hydraulic cylinder cannot extend further as pressure increases. Movement of the hydraulic cylinder's hollow piston rod does not affect the outflow of liquid from the outlet.

[0015] The beneficial effect of the present invention is that the operation of the hydraulic cylinder is realized by the liquid supply pressure through a special mechanical structure, and overpressure monitoring or overpressure movement is provided with power. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below with reference to the accompanying drawings.

[0017] Attachment Figure 1 This is the general diagram of the overpressure self-elevating hydraulic cylinder;

[0018] Attachment Figure 2 This is the end structure diagram of the overpressure self-lifting hydraulic cylinder.

[0019] In the figure, 1. hydraulic cylinder mounting plate, 2. hydraulic cylinder flange, 3. hydraulic cylinder body, 4. liquid inlet connection port, 5. hollow piston rod, 6. liquid inlet pipe, 7. return spring sleeve, 8. return spring, 9. piston, 10. flange bolt, 11. liquid outlet, 12. piston seal, and 13. piston fixing nut. DETAILED DESCRIPTION

[0020] In the attached Figure 1 In the utility model, the overpressure self-lifting hydraulic cylinder includes a hydraulic cylinder body 3, a hollow piston rod 5, a piston 9 and a return spring 8. The hollow piston rod 5 is arranged in the hydraulic cylinder body 3, and a hole is opened at the end of the hydraulic cylinder body 3. One end of the hollow piston rod 5 extends out of the opening, and a piston is provided at the other end to contact the inner wall of the hydraulic cylinder body 3; the end of the hollow piston rod extending out of the hydraulic cylinder body 3 is a hydraulic outlet, which is connected to the return liquid pipe.

[0021] The piston end of the hydraulic cylinder body 3 is opened as a hydraulic inlet, which is connected to the hydraulic high-pressure oil pipe. A return spring 8 is sleeved on the outside of the hollow piston rod 5. One end of the return spring 8 is connected to the inner side of the opening of the hydraulic cylinder body 3 for a circle, and the other end is connected to the upper side of the piston. A sleeve 7 is provided on the outside of the piston rod to isolate the return spring 8 from the outer side of the hollow piston rod 5. This protects the surface of the hollow piston rod 5 from friction with the return spring 8.

[0022] In this device, the length of the sleeve 7 is 1 / 3 to 1 / 2 of the length of the hollow piston rod.

[0023] A hydraulic cylinder flange 2 is provided around the open end of the hydraulic cylinder. The hydraulic cylinder flange 2 is fixed to a hydraulic cylinder mounting plate 1 by bolts. The hydraulic cylinder mounting plate 1 is provided with mounting through holes.

[0024] The hydraulic high-pressure oil pipe connected to the hydraulic inlet is laid on the outside of the hydraulic cylinder body, and a liquid inlet connection port 4 is provided at the protruding end of the hollow piston rod.

[0025] The hydraulic cylinder mounting plate 1 and the hydraulic cylinder flange 2 of the device are evenly distributed with mounting through holes, and the flange above the hydraulic cylinder body 3 has screw holes, and the hydraulic cylinder mounting plate 1 and the hydraulic cylinder flange 2 are fixed to the flange above the hydraulic cylinder body 3 with bolts.

[0026] In this device, the hollow piston rod 5 has a clearance fit with the hydraulic cylinder flange 2 to provide guidance. A fluid outlet 11 is located above the hollow piston rod 5, and a piston 9 is mounted below via a piston retaining nut 13. A return spring 8 is sleeved around the hollow piston rod 5, with its lower surface in contact with the upper surface of the piston 9 and its upper surface in contact with the lower surface of the hydraulic cylinder flange 2.

[0027] When the hydraulic pressure at the liquid inlet connection port 4 of the overpressure self-lifting hydraulic cylinder is less than or equal to the design value, which is the liquid pressure generated by the resistance of the piston 9 and the elastic force of the return spring 8, and this pressure is the minimum self-lifting pressure of the overpressure self-lifting hydraulic cylinder, the piston 9 does not move, and the liquid can flow into the interior through the small hole below the hollow piston rod 5 from the liquid inlet connection port 4 and out through the liquid outlet 11. When the hydraulic pressure at the liquid inlet connection port 4 of the overpressure self-lifting hydraulic cylinder is greater than the design value, the liquid pressure below the piston 9 can overcome the resistance and the elastic force of the return spring 8, the hollow piston rod 5 moves upward, the return spring 8 is compressed, and the elastic force increases. When the liquid pressure below the piston 9 cannot overcome the resistance and the elastic force of the return spring 8, the piston 9 stops moving. When the hydraulic pressure at the liquid inlet port 4 decreases, the piston 9 moves downward until it is less than the design value and the piston 9 drops to the lowest position. At this time, the liquid can still flow out through the liquid inlet port 4 through the liquid outlet 11. The maximum upward movement position of the piston 9 is limited by the height of the return spring sleeve 7. When the piston 9 moves upward to the highest position, the liquid pressure at the liquid inlet 4 is the maximum self-lifting pressure of the overpressure self-lifting hydraulic cylinder. After the liquid pressure at the liquid inlet 4 exceeds the maximum self-lifting pressure, the piston 9 will no longer move upward.

[0028] This hydraulic cylinder relies on liquid pressure to achieve expansion and contraction. The invention relies on whether the pressure at the hydraulic cylinder inlet exceeds the design value to achieve the movement of the hydraulic cylinder piston, which has important practical value in some working conditions.

Claims

1. An overpressure self-elevating hydraulic cylinder, characterized in that: It comprises a hydraulic cylinder body (3), a hollow piston rod (5), a piston (9) and a return spring (8), wherein the hollow piston rod (5) is arranged in the hydraulic cylinder body (3), an end of the hydraulic cylinder body (3) is provided with a hole, one end of the hollow piston rod (5) extends out of the hole, and a piston is arranged at the other end to contact the inner wall of the hydraulic cylinder body (3); The end of the hollow piston rod extending out of the hydraulic cylinder body (3) is a hydraulic outlet connected to a liquid return pipe; The piston end of the hydraulic cylinder body (3) is opened as a hydraulic inlet, which is connected to a hydraulic high-pressure oil pipe. A return spring (8) is sleeved on the outside of the hollow piston rod (5). One end of the return spring (8) is connected to the inner side of the opening of the hydraulic cylinder body (3) and the other end is connected to the upper side of the piston.

2. The overpressure self-elevating hydraulic cylinder according to claim 1, characterized in that: A sleeve (7) is provided on the outside of the piston rod, and the sleeve (7) isolates the return spring (8) from the outer side surface of the hollow piston rod (5).

3. The overpressure self-elevating hydraulic cylinder according to claim 2, characterized in that: The length of the sleeve (7) is 1 / 3 to 1 / 2 of the length of the hollow piston rod.

4. The overpressure self-elevating hydraulic cylinder according to claim 1, characterized in that: The hydraulic cylinder is provided with a hydraulic cylinder flange (2) around the open end, and the hydraulic cylinder flange (2) is fixed to the hydraulic cylinder mounting plate (1) by means of bolts. The hydraulic cylinder mounting plate (1) is provided with mounting through holes.

5. The overpressure self-elevating hydraulic cylinder according to claim 1, characterized in that: The hydraulic high-pressure oil pipe connected to the hydraulic inlet is laid outside the hydraulic cylinder body, and a liquid inlet connection port (4) is provided at the protruding end of the hollow piston rod.

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