Double acting damper piston rod

Abstract

The double-acting damper piston rod disclosed in the present invention is intended to provide a damper piston rod that can provide flow capacity for the damper and can stably operate the hydraulic damper pressure limiting valve under large flow. The present invention is implemented through the following technical scheme: four symmetrically distributed valve holes and pressure limiting valves installed in the valve holes are evenly distributed on the circumference of the two ends of the piston, each pressure limiting valve is fixed in the valve hole by a pressure limiting valve seat with a through hole, and two symmetrically distributed valve holes arranged on the same side of the two sides of the piston are respectively equipped with heterogeneous pressure limiting valves, and the four heterogeneous pressure limiting valves are symmetrical and orthogonal to each other in space, and the pressure limiting valve core and the pressure limiting spring are constrained to reciprocate in the valve hole cavity formed by the pressure limiting valve seat, and each pressure limiting valve core controls the unidirectional flow of oil pressure through the elastic pressure of the set pressure limiting spring. The present invention solves the vibration problem caused by insufficient flow capacity of the hydraulic damper pressure limiting valve.

Description

Technical Field

[0001] The invention relates to a piston rod structure integrated with a pressure limiting valve and applied to a hydraulic damper. Background Art

[0002] The hydraulic damper is a device that uses damping characteristics to slow down mechanical vibration and consume kinetic energy. It can effectively prevent the resonance and impact of the mechanical system in the mechanical system and inhibit the operator from operating the control device too quickly. The damper contains a lot of content, such as damping elements, piston rods, pressure limiting valves, connecting rod ends, compensation structures, etc., and there are various combinations, each with different advantages. The hydraulic damper controls the movement of the piston rod with the help of a special valve. Under normal working conditions, when the piston rod speed V is less than the critical speed V0, the pressure difference between the two damping chambers is small and insufficient to open the pressure limiting valve. The hydraulic oil can only flow through the damping orifice to form a damping force. When an instantaneous impact load occurs, V increases to V0, and the pressure difference between the two damping chambers is large enough. The high-pressure oil pushes the valve core, so that the valve core overcomes the spring force and opens. The two chambers communicate to achieve the maximum pressure control, thereby achieving the purpose of vibration reduction and anti-vibration. In order to prevent the hydraulic damper from being damaged by too high pressure in the inner chamber during the damping function, a pressure limiting valve is set in the damper to control the maximum pressure. The piston of the hydraulic damper has two movement directions, and pressure limiting valves need to be arranged in both directions. The pressure limiting valve is a pressure safety automatic valve, whose function is to control the internal pressure of the hydraulic damper within the specified range. The opening pressure of the pressure limiting valve is controlled by the spring force of the spring. When the force exerted by the oil pressure on the valve core is greater than the spring force, the valve opens, and the two damping chambers separated by the piston communicate through the opened pressure limiting valve to achieve pressure relief, and the internal pressure of the damper no longer rises. The pressure limiting valve is generally composed of a pressure limiting valve core, a pressure limiting valve seat, a pressure limiting spring and a pressure regulating gasket. The current mature and commonly used method of arranging the pressure limiting valve is to arrange it on the piston rod. The traditional method of arranging two pressure limiting valves on one piston rod, one in each direction, can no longer meet the requirements of stable operation under large flow conditions, and vibration is inevitable. Taking the helicopter rotor hydraulic damper as an example, during the takeoff and flight of the helicopter, the main rotor blades can swing back and forth in the rotation plane in the equilibrium position. During this process, if the blade is disturbed by the airflow, it will deflect. Since the blade connection mechanism itself has very little damping, after the disturbance is eliminated, the blade will continue to swing near the equilibrium position, affecting flight safety. To solve this problem, it is necessary to artificially add a hydraulic damper to the rotor system to consume the vibration energy of the mechanism, converge the movement, and avoid divergent vibration of the mechanism. The rotor hydraulic damper needs to provide damping in both the extension and retraction directions of the piston. Foreign rotor hydraulic dampers, such as the Black Hawk damper, have a pressure limiting valve arranged in each of the two axial directions of the piston. The Black Hawk damper can stably provide a damping amplitude (piston movement distance) of up to 16 mm at a frequency of 4.3 Hz, and can provide a damping force of 17,000 N. Nowadays, helicopters are becoming more and more advanced, and the requirements for maneuverability are getting higher and higher. Hydraulic dampers are required to provide not only precise damping at small amplitudes (e.g. 3mm), but also sufficient damping force (e.g. 23000N) at large amplitudes (e.g. 16mm) to suppress blade swing.This requires that the hydraulic damper pressure limiting valve can work stably under large flow conditions. The structure of a pressure limiting valve in each direction of the piston rod (same-direction single pressure limiting valve) adopted in the prior art will inevitably vibrate. It is difficult to meet the current requirements for the damping performance of the hydraulic damper. Summary of the invention

[0003] The task of the present invention is to address the deficiencies in the prior art and provide a hydraulic damper pressure limiting valve that can provide flow capacity for the damper and can work stably under large flow conditions, prevent valve body resonance, and double-acting damper piston rod to solve the hydraulic damper vibration problem caused by excessive internal flow and insufficient flow capacity of the pressure limiting valve under high-frequency and large-amplitude working conditions.

[0004] The technical solution adopted by the present invention to solve its technical problem is a double-acting damper piston rod, which has a piston rod 3 that can make linear motion in the hydraulic damping chamber of the hydraulic damper and a piston connected to the piston rod body, characterized in that: four symmetrically distributed valve holes and pressure-limiting valves installed in the valve holes are evenly distributed on the circumference of the two side ends of the piston, each pressure-limiting valve is fixed in the valve hole by a pressure-limiting valve seat with a through hole, and two symmetrically distributed valve holes arranged in the same side direction on both sides of the piston are respectively equipped with heterogeneous pressure-limiting valves, and the four heterogeneous pressure-limiting valves are symmetrical and orthogonal to each other in space, and the pressure-limiting valves The core and the pressure-limiting spring are constrained to make reciprocating motion in the valve hole cavity formed by the pressure-limiting valve seat, and each pressure-limiting valve core controls the unidirectional flow of oil pressure through the elastic pressure of the installed pressure-limiting spring; when the pressure of the working medium at both ends of the piston exceeds the set value, the heterogeneous pressure-limiting valve at one end of the piston opens, thereby reducing the pressure at one end of the damping chamber 4; when the pressure reaches the lower limit, the heterogeneous pressure-limiting valve closes, and the pressure at the other end of the damping chamber 4 rises, and the hydraulic oil pushes the valve core to overcome the spring force to control the circulation of the flowing hydraulic oil and the switching of the heterogeneous pressure-limiting valve, so that the working medium pressure on both sides of the piston is adjusted repeatedly to form a damping force that compensates each other on both sides of the damping chamber 4.

[0005] Compared with the prior art, the present invention has the following beneficial effects:

[0006] The present invention arranges four pressure limiting valves on the piston rod, and there are two pressure limiting valves in each direction of the two axial directions of the piston rod, which is simple, compact, stable and reliable in operation. The four heterogeneous pressure limiting valves greatly improve the flow capacity of the piston rod pressure limiting valve, reduce the flow capacity requirements of a single pressure limiting valve, and make the structural design simpler, thereby increasing the reliability and stability of the pressure limiting valve.

[0007] The present invention adopts four symmetrically distributed valve holes equally distributed on the circumference of the two side ends of the piston and a pressure-limiting valve assembled in the valve hole, and the four dual-pressure-limiting heterogeneous pressure-limiting valves are symmetrical and orthogonal to each other in space, and two symmetrical pressure-limiting valve structures with different pressure-limiting valve core structures, different weights, and pressure-limiting spring stiffnesses are adopted in the same direction. This double-acting damper piston rod can prevent resonance caused by the same natural frequency of the two valves, and can solve the vibration problem of the hydraulic damper caused by excessive internal flow and insufficient flow capacity of the pressure-limiting valve under high-frequency and large-amplitude working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a right side view of the piston rod of the double-acting damper of the present invention.

[0009] Figure 2 yes Figure 1 AA is a cross-sectional view rotated 90° counterclockwise.

[0010] Figure 3 yes Figure 1 BB cross-sectional view.

[0011] Figure 4 It is a schematic diagram of the working principle of an optional embodiment of the present invention in a hydraulic damper.

[0012] In the figure: 1 cylinder rod end, 2 piston rod end universal joint, 3 piston rod, 4 damping chamber, 5 damping orifice, 6 right-opening round head pressure-limiting cone valve core, 7 right-opening flat head pressure-limiting cone valve core, 8 left-hand cone head valve core, 9 left-hand cone flat head valve core, 10 right-hand round head pressure-limiting spring, 11 right-hand flat head pressure-limiting spring, 12 left-hand cone pressure-limiting spring, 13 left-hand flat head pressure-limiting spring, 14 right-hand round head pressure-limiting valve seat, 15 right-hand flat head pressure-limiting valve seat, 16 left-hand round head cover valve seat, 17 left-hand flat head cover valve seat, 18 first right-opening one-way pressure-limiting valve, 19 second right-opening one-way pressure-limiting valve, 20 second left-opening one-way pressure-limiting valve, 21 first left-opening one-way pressure-limiting valve.

[0013] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited to the scope of the embodiments described. All these concepts should be regarded as the content disclosed by the present technology and the protection scope of the present invention. DETAILED DESCRIPTION

[0014] See also Figure 1-Figure 3 In the name of the double-acting damper piston rod, the same direction means that the piston rod has two directions of movement, and a double valve is arranged in each direction of movement; the double pressure-limiting valve means that the piston rod has two directions of movement, and two pressure-limiting valves are arranged in each direction, for a total of four pressure-limiting valves. Heterogeneous means that the two pressure-limiting valves in the same direction have different structures, to prevent resonance from occurring during operation due to the same structure and the same natural frequency, resulting in unstable operation.

[0015] In the embodiment described below, the double-acting damper piston rod has a piston rod 3 that can make linear motion in the hydraulic damping chamber of the hydraulic damper and a piston connected to the piston rod body. Four symmetrically distributed valve holes and pressure-limiting valves installed in the valve holes are evenly distributed on the circumference of the two ends of the piston. Each pressure-limiting valve is fixed in the valve hole by a pressure-limiting valve seat with a through hole, and two symmetrically distributed valve holes arranged on the same side of the piston are respectively equipped with heterogeneous pressure-limiting valves. The four double-pressure-limiting heterogeneous pressure-limiting valves are symmetrical and orthogonal to each other in space. The pressure-limiting valve core and the pressure-limiting spring are constrained to make reciprocating motion in the valve hole cavity formed by the pressure-limiting valve seat. Each pressure-limiting valve core is sleeved. The elastic pressure of the installed pressure-limiting spring is used to control the unidirectional flow of oil pressure; when the pressure of the working medium at both ends of the piston exceeds the set value, the heterogeneous pressure-limiting valve at one end of the piston opens to reduce the pressure at one end of the damping chamber 4; when the pressure reaches the lower limit, the heterogeneous pressure-limiting valve closes, and the pressure at the other end of the damping chamber 4 rises. The hydraulic oil pushes the valve core to overcome the spring force to control the circulation of the flowing hydraulic oil and the switching of the heterogeneous pressure-limiting valve. The working medium pressure on both sides of the piston is adjusted repeatedly in this way to form a damping force that compensates each other on both sides of the damping chamber 4.

[0016] A first right-opening one-way pressure-limiting valve 18, a second right-opening one-way pressure-limiting valve 19, a second left-opening one-way pressure-limiting valve 20, and a first left-opening one-way pressure-limiting valve 21 are fixedly connected to the piston of the piston rod 3. The first right-opening one-way pressure-limiting valve 18 and the second right-opening one-way pressure-limiting valve 19 have the same opening direction and are respectively arranged on the upper and lower sides of the piston; the second left-opening one-way pressure-limiting valve 20 and the first left-opening one-way pressure-limiting valve 21 have the same opening direction and are respectively arranged on the left and right sides of the piston.

[0017] See also Figure 2 On the right side circumference of the piston, two heterogeneous dual pressure-limiting valves symmetrically distributed about the piston rod 3 include a first left-open one-way pressure-limiting valve 21 consisting of a left-facing cone flat-head valve core 9 constrained in a valve hole cavity formed by a left-facing round-head valve seat 17 and a left-facing flat-head pressure-limiting spring 13 mounted thereon, and a second left-open one-way pressure-limiting valve 20 consisting of a left-facing cone-head valve core 8 constrained in a valve hole cavity formed by a left-facing round-head cover valve seat 16 and a left-facing cone pressure-limiting spring 12 mounted thereon. The second left-open one-way pressure-limiting valve 20 has the same opening direction as the first left-open one-way pressure-limiting valve 21, and is arranged on the left and right sides of the piston, respectively.

[0018] See also Figure 3The first right-opening one-way pressure-limiting valve 18 and the second right-opening one-way pressure-limiting valve 19 are two pressure-limiting valves that work when the piston rod 3 moves to the right. The first right-opening one-way pressure-limiting valve 18 is composed of a right-hand round-headed pressure-limiting valve seat 14, a right-hand round-headed pressure-limiting cone valve core 6 and a right-hand round-headed pressure-limiting spring 10, which are assembled on the right side end of the piston. The right-hand round-headed pressure-limiting cone valve core 6 performs reciprocating linear motion in the cavity formed by the piston rod 3 and the right-hand round-headed pressure-limiting valve seat 14. The second right-opening one-way pressure-limiting valve 19 is composed of a right-hand flat-headed pressure-limiting valve seat 15, a right-hand flat-headed pressure-limiting cone valve core 7 and a right-hand flat-headed pressure-limiting spring 11, which are assembled on the right side end of the piston. The first right-opening one-way pressure-limiting valve 18 and the second right-opening one-way pressure-limiting valve 19 have the same opening direction and are arranged on the upper and lower sides of the piston respectively. They are two isotropic pressure-limiting valves that work when the piston rod 3 moves to the right. The right-opening flat-head pressure-limiting cone valve core 7 performs reciprocating linear motion in the cavity formed by the piston rod 3 and the right-opening flat-head pressure-limiting valve seat 15. When the piston rod moves to the right, when the pressure in the right damping chamber reaches the set pressure, the hydraulic pressure pushes the right-opening round-head pressure-limiting cone valve core 6 and the right-opening flat-head pressure-limiting cone valve core 7 to compress the right-opening round-head pressure-limiting spring 10 and the right-opening flat-head pressure-limiting spring 11 respectively, so that the pressure-limiting valve is opened and the two hydraulic chambers communicate, so as to achieve the purpose of controlling the maximum pressure of the inner cavity when the piston rod moves to the right.

[0019] See also Figure 4 . In the following optional embodiments, the hydraulic damper is connected to the mechanical system through the cylinder rod end 1 and the piston rod end universal joint 2, the piston rod 3 is fixedly connected to the piston rod end universal joint 2, and the piston of the piston rod 3 divides the damping chamber 4 of the hydraulic damper into two chambers. When the external mechanical movement drives the piston rod 3 to move through the piston rod end universal joint 2, the piston rod presses one chamber of oil to increase the pressure of the oil in this chamber, forming a pressure difference with the other chamber. The pressure difference causes the oil to enter the other chamber through the damping hole 5. The damping hole 5 causes the liquid molecules to squeeze and rub against each other, thereby converting mechanical energy into heat energy, realizing the damping effect of the hydraulic damper. In order to prevent the hydraulic damper from being damaged by too high an internal chamber pressure during the process of realizing the damping function, a pressure limiting valve needs to be set in the damper to control the maximum pressure. The piston rod of the hydraulic damper has two movement directions. In this embodiment, two different pressure limiting valves are arranged in the two directions of the piston rod 3. When the piston rod 3 moves to the right, when the pressure in the right chamber reaches the set pressure, the first right-opening one-way pressure limiting valve 18 and the second right-opening one-way pressure limiting valve 19 are opened, and the two chambers communicate to achieve pressure relief, limiting the pressure from rising. When the piston rod 3 moves to the left, when the pressure in the left chamber reaches the set pressure, the second left-opening one-way pressure limiting valve 20 and the first left-opening one-way pressure limiting valve 21 are opened, and the two chambers communicate to achieve pressure relief, limiting the pressure from rising.

[0020] The embodiments of the present invention are introduced in detail above. The present invention is explained in this article using specific implementation methods. In the description of the above embodiments, data such as the number of ground stations, the number of beams, and the number of satellites are only used to help understand the methods and equipment of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the contents of the embodiments of this specification should not be understood as limiting the present invention.

Claims

1. A double-acting damper piston rod, comprising a piston rod (3) capable of linear motion in a hydraulic damping chamber of the hydraulic damper and a piston connected to the piston rod body, characterized in that: Four symmetrically distributed valve holes and pressure-limiting valves installed in the valve holes are evenly distributed on the circumference of the ends of both sides of the piston. Each pressure-limiting valve is fixed in the valve hole by a pressure-limiting valve seat with a through hole, and two symmetrically distributed valve holes arranged on the same side of the piston are respectively equipped with heterogeneous pressure-limiting valves. The four heterogeneous pressure-limiting valves are symmetrical and orthogonal to each other in space. The pressure-limiting valve core and the pressure-limiting spring are constrained to make reciprocating motion in the valve hole cavity formed by the pressure-limiting valve seat. Each pressure-limiting valve core controls the single pressure of the oil pressure through the elastic pressure of the set pressure-limiting spring. When the pressure of the working medium at both ends of the piston exceeds a set value, the isomeric pressure-limiting valve at one end of the piston opens, causing the pressure at one end of the damping chamber (4) to decrease. When the pressure reaches a lower limit, the isomeric pressure-limiting valve closes, causing the pressure at the other end of the damping chamber (4) to increase. The hydraulic oil pushes the valve core to overcome the spring force to control the flow of the hydraulic oil and the switching of the isomeric pressure-limiting valve. This cycle repeatedly adjusts the pressure of the working medium at both sides of the piston, forming a damping force that compensates for each other on both sides of the damping chamber (4). The pressure-limiting valve cores of the two isomeric pressure-limiting valves used in the same direction have different structures and weights.

2. The double-acting damper piston rod according to claim 1, characterized in that On the circumference of the right end of the piston, two heterogeneous dual pressure-limiting valves symmetrically distributed about the piston rod (3) include a first left-opening one-way pressure-limiting valve (21) consisting of a left-facing conical flat-head valve core (9) constrained in a valve hole cavity formed by a left-facing round-head valve seat (17) and a left-facing flat-head pressure-limiting spring (13) mounted thereon, and also include a second left-opening one-way pressure-limiting valve (20) consisting of a left-facing conical head valve core (8) constrained in a valve hole cavity formed by a left-facing round-head cover valve seat (16) and a left-facing conical pressure-limiting spring (12) mounted thereon.

3. The double-acting damper piston rod according to claim 1, characterized in that The second left-opening one-way pressure-limiting valve (20) and the first left-opening one-way pressure-limiting valve (21) have the same opening direction and are arranged on the left and right sides of the piston respectively.

4. The double-acting damper piston rod according to claim 1, characterized in that The first right-opening one-way pressure-limiting valve (18) is composed of a right-opening round-head pressure-limiting valve seat (14) assembled on the right side end of the piston, a right-opening round-head pressure-limiting cone valve core (6) and a right-opening round-head pressure-limiting spring (10). The right-opening round-head pressure-limiting cone valve core (6) performs reciprocating linear motion in a cavity formed by the piston rod (3) and the right-opening round-head pressure-limiting valve seat (14).

5. The double-acting damper piston rod according to claim 1, characterized in that The second right-opening one-way pressure-limiting valve (19) is composed of a right-opening flat-head pressure-limiting valve seat (15) assembled on the right side end of the piston, a right-opening flat-head pressure-limiting cone valve core (7) and a right-opening flat-head pressure-limiting spring (11).

6. The double-acting damper piston rod according to claim 1, characterized in that The first right-opening one-way pressure-limiting valve (18) and the second right-opening one-way pressure-limiting valve (19) have the same opening direction and are arranged on the upper and lower sides of the piston respectively. They are two isotropic pressure-limiting valves that work when the piston rod (3) moves to the right. The right-opening flat-head pressure-limiting cone valve core (7) performs reciprocating linear motion in the cavity formed by the piston rod (3) and the right-opening flat-head pressure-limiting valve seat (15).

7. The double-acting damper piston rod according to claim 1, characterized in that When the piston rod moves to the right and the pressure in the right damping chamber reaches the set pressure, the hydraulic pressure pushes the right-open round-head pressure-limiting cone valve core (6) and the right-open flat-head pressure-limiting cone valve core (7) to compress the right-direction round-head pressure-limiting spring (10) and the right-direction flat-head pressure-limiting spring (11) respectively, thereby opening the pressure-limiting valve and communicating with the two hydraulic chambers, thereby achieving the maximum pressure in the inner chamber when the piston rod moves to the right.

8. The double-acting damper piston rod according to claim 1, characterized in that The hydraulic damper is connected to the mechanical system through the cylinder rod end (1) and the piston rod end universal joint (2), and the piston rod (3) is fixedly connected to the piston rod end universal joint (2).

9. The double-acting damper piston rod according to claim 1, characterized in that The piston of the piston rod (3) divides the damping chamber (4) of the hydraulic damper into two chambers. When the external mechanical movement drives the piston rod (3) to move through the universal joint (2) at the piston rod end, the piston rod presses the oil in one chamber to increase the oil pressure in the chamber, thereby forming a pressure difference with the other chamber. The pressure difference causes the oil to enter the other chamber through the damping hole (5). The damping hole (5) causes the liquid molecules to squeeze and rub against each other, thereby converting mechanical energy into heat energy, thereby realizing the damping effect of the hydraulic damper.

10. The double-acting damper piston rod according to claim 1, characterized in that Two different pressure limiting valves are arranged in two directions of the piston rod (3). When the piston rod (3) moves to the right and the pressure in the right chamber reaches a set pressure, the first right-opening one-way pressure limiting valve (18) and the second right-opening one-way pressure limiting valve (19) are opened, and the two chambers are communicated to achieve pressure relief, thereby limiting the pressure from rising further; when the piston rod (3) moves to the left and the pressure in the left chamber reaches a set pressure, the second left-opening one-way pressure limiting valve (20) and the first left-opening one-way pressure limiting valve (21) are opened, and the two chambers are communicated to achieve pressure relief, thereby limiting the pressure from rising further.

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