CN216895162U - Hydraulic actuator tail end damping buffer mechanism - Google Patents

Abstract

The damping buffer mechanism at the tail end of the hydraulic actuator disclosed by the utility model is compact in structure and quick in response. The utility model is realized by the following technical scheme: the piston rod divides the working cylinder barrel into a buffer cavity and a hydraulic cavity, the radial nozzle of the end cover is communicated with the buffer cavity to the eccentric flow channel through the end on the central step hole of the end cover towards the throttling hole and the end of the lower eccentric step hole of the throttling hole respectively, the first-step shaft of the piston rod is fixedly connected with the sleeve, the end part of the second-step cantilever valve rod is fixedly connected with the locking nut, the buffer valve core assembled on the valve rod of the piston rod is sleeved with the buffer spring and constrained between the locking nut and the spring seat outside the outer sleeve of the piston rod, the buffer valve core is limited by the locking nut, is stressed by the buffer spring force and can reciprocate on the valve rod of the piston rod, and the eccentric step hole is internally provided with the one-way valve core and the reset spring and is supported by the limit washer. Under the flow limiting effect of the damping hole of the one-way valve core, the motion stroke of the tail end of the piston rod is subjected to hydraulic reverse thrust, the motion speed is gradually reduced and finally becomes constant speed until the end, and the buffer is realized.

Description

Hydraulic actuator tail end damping buffer mechanism

Technical Field

The utility model relates to a hydraulic actuator with a tail end damping function, which is mainly used for hydraulic system actuating mechanisms in the industries of aviation, aerospace, ships, vehicles, large-scale engineering equipment and the like.

Background

In hydropneumatic transmission systems, power is transmitted and controlled by a pressurized fluid gas in a closed circuit. Actuators (actuators) are a common type of Actuator element in hydropneumatic transmission systems, and the working medium is typically both liquid and gas. The actuators are generally classified into two types, a reciprocating linear actuator and a reciprocating swing type actuator, which are devices for converting pneumatic or hydraulic power into mechanical force and motion. When the actuator drives a moving part having a large mass and the moving speed is large, the inertia of the moving part is large, and when the piston/piston rod of the actuator moves to the limit position, shock and noise due to mechanical collision are liable to occur. The arrangement of the buffer mechanism at the end of the stroke inside the hydraulic cylinder can enable the piston part driving the load to decelerate when reaching the end of the stroke, and aims to reduce the mechanical impact between the piston and the end cover caused by the inertia force and the hydraulic pressure of the piston part. The stroke end buffering mechanism of the hydraulic cylinder usually adopts a buffer of an energy buffering method, so that hydraulic oil which is finally discharged back to an oil tank in a low-pressure cavity of the hydraulic cylinder is sealed and flows out through a throttling hole or a gap, and the aim of reducing speed is fulfilled. Meanwhile, the fluid in the buffer cavity generates internal pressure to resist the action of inertia force and other external forces to realize buffering. The energy conversion mechanism is to convert kinetic energy into heat energy, and the heat energy is carried out of the hydraulic cylinder by the circulating fluid. The buffer mechanism is generally in the structural form of small hole throttling, circular seam throttling or the combination of small holes and circular seams. The circular seam throttling is realized by forming a circular seam through the clearance fit of the cylinder and the shaft, so that the circulation of fluid is not smooth, the matching clearance of the cylinder and the shaft is small, the requirement on processing precision is high, and the processing difficulty is high. Influenced by the processing precision, the non-concentricity probability of the assembled cylinder and the shaft is high, the debugging is difficult, and the performance consistency is poor. The orifice throttling realizes throttling by blocking free circulation of fluid through the orifice, and the orifice has the advantages of simple processing, easy product debugging and better performance consistency. In the buffer design of the hydraulic actuator, circular seam throttling is commonly used for tail end buffering, small hole throttling is commonly used for full-stroke buffering, and the tail end buffering is rarely realized by adopting the small hole throttling.

Disclosure of Invention

The utility model aims to solve the problems in the prior art and aims to provide a hydraulic actuator which is compact in structure, low in manufacturing cost and high in response speed, and particularly has a small-hole throttling type tail end buffering function.

The above object of the present invention can be achieved by a hydraulic actuator end damping buffer mechanism, comprising: end cover 1 with joint bearing pilot hole and radial mouthpiece 2, with 1 internal thread connection of end cover and sealed work cylinder 6 in 1 port barrel of end cover, reciprocating motion is direct to the integral type variable cross section piston rod 8 of external acting in work cylinder 6, connect firmly sleeve 7 on 8 first-order step shaft threads of piston rod, fasten lock nut 12 on 8 second order cantilever valve rod end screw threads of piston rod, the cover is equipped with buffer spring 10 and is restrained at lock nut 11 between the 8 valve rod outer sleeve spring seats of piston rod, its characterized in that: the piston rod 8 which runs in the working cylinder 6 in a sealed mode divides the working cylinder 6 into a buffer cavity 5 and a hydraulic cavity 9, a flow channel of the nozzle 2 is communicated with a central step hole 3 in the middle of the end cover 1 and an eccentric step hole 14 below the central step hole 3 through a throttling hole 19 and an eccentric flow channel 18, a one-way valve core 16 and a return spring 15 are arranged in the eccentric step hole 14 and supported by a limiting gasket 4 fixed between the end cover 1 and the working cylinder 6, and the eccentric step hole 14 and the buffer cavity 5 are communicated through an eccentric through hole 13 in the limiting gasket 4. The sleeve 7 is used for limiting the leftward movement of the piston rod 8, the buffer valve core 11 and the orifice of the central stepped hole 3 are both provided with sealing conical surfaces, the buffer valve core 11 is limited by the locking nut 12, is stressed by the buffer spring 10 and can reciprocate on the valve rod of the piston rod 8, the moving surface is sealed, and the one-way valve core 16 and the orifice of the eccentric flow channel 18 are sealed in a conical surface manner in a free state. Hydraulic oil enters the hydraulic cavity 9 to push the piston rod 8 to move leftwards, before the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3, oil in the buffer cavity 5 can be discharged into a flow channel of the nozzle 2 through two paths of 'the central stepped hole 3-the orifice 19' and 'the eccentric through hole 13-the eccentric stepped hole 14-the damping hole 17-the eccentric flow channel 18', the oil flow is not limited, the oil pressure in the buffer cavity 5 is not increased, no reverse thrust is generated on the piston rod 8, and no buffer exists; the piston rod 8 continues to move leftwards, the locking nut 12 is driven to enter the central stepped hole 3, the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3, the buffer valve core 11 is blocked and does not move along with the piston rod 8 any more, the buffer valve core 11 is in contact sealing with the sealing conical surface of the orifice of the central stepped hole 3 under the pre-pressure action of the buffer spring 10, a channel which is discharged into the nozzle 2 through the central stepped hole 3-the throttling hole 19 is blocked, and oil in the buffer cavity 5 can only be discharged into a flow channel of the nozzle 2 through the eccentric through hole 13-the eccentric stepped hole 14-the damping hole 17-the eccentric flow channel 18; the piston rod 8 compresses the buffer spring 10 to drive the lock nut 12 to continue to move towards the inside of the central stepped hole 3, the pressure in the buffer cavity 5 is increased under the current limiting effect of the damping hole 17, and the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3 more tightly under the combined action of the force of the buffer spring 10 and the hydraulic pressure of the buffer cavity 5. The hydraulic pressure in the buffer cavity 5 generates a rightward reverse thrust to the piston rod 8 to reduce the movement speed of the piston rod 8, the reverse thrust is finally balanced with a leftward load applied to the piston rod 8, and the piston rod 8 finally moves at a constant speed until the sleeve 7 is contacted with the limit washer 4 and then stops moving. In the whole process, the movement speed of the piston rod 8 is gradually reduced from an initial value to move at a constant speed at a lower speed and finally stops, the bottom collision energy of the piston rod is weakened, and the buffer is realized.

Compared with the prior art, the utility model has the following beneficial effects.

The utility model adopts an end cover 1 with a radial nozzle 2, a working cylinder 6 encapsulated with the end cover 1, an integrated variable cross-section piston rod 8 which reciprocates in the working cylinder 6 and directly applies work outwards, a sleeve 7 fixedly connected on a first-order step shaft thread of the piston rod 8, a lock nut 12 fastened on a second-order cantilever valve rod end thread of the piston rod 8, a buffer valve core 11 sleeved with a buffer spring 10 and restrained between the lock nut 12 and a valve rod outer sleeve spring seat of the piston rod 8, a one-way valve core 16 and a reset spring 15 arranged in an eccentric step hole 14, and a limit washer 4 which is fixed between the end cover 1 and the working cylinder 6 and is provided with an eccentric through hole 13 to form a tail end damping buffer mechanism, and the utility model has the advantages of compact and simple structure and low manufacturing cost.

The utility model adopts a piston rod 8 which is sealed in a working cylinder 6 to operate to divide the working cylinder 6 into a buffer cavity 5 and a hydraulic cavity 9, a flow passage of a nozzle 2 is respectively communicated with a central step hole 3 in an end cover 1 and an eccentric step hole 14 below the central step hole through a throttling hole 19 and an eccentric flow passage 18, a buffer valve core 11 is sleeved with a buffer spring 10 and is restrained between a locking nut 12 and a spring seat outside a valve rod of the piston rod 8, the buffer valve core 11 can reciprocate on the valve rod of the piston rod 8, the moving surface is sealed, a one-way valve core 16 and a reset spring 15 are arranged in the eccentric step hole 14 and are supported by a limit washer 4 fixed between the end cover 1 and the working cylinder 6, and the eccentric step hole 14 and the buffer cavity 5 are communicated by an eccentric through hole 13 on the limit washer 4. The sleeve 7 is used for limiting the leftward movement of the piston rod 8, the buffer valve core 11 and the orifice of the central step hole 3 are both provided with sealing conical surfaces, and the one-way valve core 16 is in conical surface sealing with the orifice of the eccentric flow passage 18 in a free state. The piston rod 8 moves leftwards after being loaded, before the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3, oil in the buffer cavity 5 flows out unhindered, no reverse thrust action and no buffer are generated on the piston rod 8, and the moving speed required by the piston rod 8 can be ensured. After the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3, the fluid in the buffer cavity 5 is limited by the damping hole 17, so that the hydraulic pressure rises to generate reverse thrust on the piston rod, and the buffer is realized. By controlling the hole diameters of the throttle hole 19 and the orifice hole 17, it is also possible to achieve simultaneous control of the movement speed of the piston rod 8 before damping and the movement speed of the damping zone.

The buffer structure converts the kinetic energy of the piston rod 8 into the heat energy of the hydraulic oil in the buffer section, and the heat energy is brought out of the pressure cylinder through the outflow of the hydraulic oil, so that the influence of impact and vibration on equipment is effectively reduced, and the problem of larger impact load caused by the excessively high movement speed of the actuator is solved.

All parts of the actuator are mechanically connected, and the reliability is good. The hydraulic damping device has the advantages of compact structure, small volume, high response speed and no special limitation requirement, and can be widely applied to hydraulic equipment with damping requirements.

Drawings

FIG. 1 is a cross-sectional view of a hydraulic actuator end dampening buffer mechanism of the present invention;

FIG. 2 is an enlarged, fragmentary schematic view of the trim valve core segment of FIG. 1;

FIG. 3 is an enlarged, fragmentary schematic view of the check valve segment of FIG. 1;

in the figure: the hydraulic control valve comprises an end cover 1, a nozzle 2, a central step hole 3, a limiting washer 4, a buffer cavity 5, a working cylinder 6, a sleeve 7, a piston rod 8, a hydraulic cavity 9, a buffer spring 10, a buffer valve core 11, a locking nut 12, an eccentric through hole 13, an eccentric step hole 14, a reset spring 15, a one-way valve core 16, a damping hole 17, an eccentric flow channel 18 and a throttling hole 19.

The utility model is further illustrated with reference to the following figures and examples, without thereby limiting the scope of the utility model to the described examples. All such concepts are intended to be within the scope of the present disclosure and patent.

Detailed Description

See fig. 1-3. In the embodiments described below, a hydraulic actuator end dampening buffer mechanism includes: end cover 1 with joint bearing pilot hole and radial mouthpiece 2, with 1 internal thread connection of end cover and sealed work cylinder 6 in 1 port barrel of end cover, reciprocating motion is direct to the integral type variable cross section piston rod 8 of external acting in work cylinder 6, connect firmly sleeve 7 on 8 first-order step shaft threads of piston rod, fasten lock nut 12 on 8 second order cantilever valve rod end screw threads of piston rod, the cover is equipped with buffer spring 10 and is restrained at lock nut 11 between the 8 valve rod outer sleeve spring seats of piston rod, its characterized in that: the piston rod 8 which runs in the working cylinder 6 in a sealed mode divides the working cylinder 6 into a buffer cavity 5 and a hydraulic cavity 9, a flow channel of the nozzle 2 is communicated with a central step hole 3 in the middle of the end cover 1 and an eccentric step hole 14 below the central step hole 3 through a throttling hole 19 and an eccentric flow channel 18, a one-way valve core 16 and a return spring 15 are arranged in the eccentric step hole 14 and supported by a limiting gasket 4 fixed between the end cover 1 and the working cylinder 6, and the eccentric step hole 14 and the buffer cavity 5 are communicated through an eccentric through hole 13 in the limiting gasket 4. The sleeve 7 is used for limiting the leftward movement of the piston rod 8, the buffer valve core 11 and the orifice of the central stepped hole 3 are both provided with sealing conical surfaces, the buffer valve core 11 is limited by the locking nut 12, is stressed by the buffer spring 10 and can reciprocate on the valve rod of the piston rod 8, the moving surface is sealed, and the one-way valve core 16 and the orifice of the eccentric flow channel 18 are sealed in a conical surface manner in a free state. The front end of a piston rod 8 pushed by hydraulic oil is provided with a buffer valve core 11 which drives a locking nut 12 to move leftwards through a buffer spring 10 arranged in a sleeve 7, the buffer valve core 11 enters a central stepped hole 3 through the locking nut 12 arranged at the end head and is attached to a sealing conical surface of an orifice of the central stepped hole 3, and the buffer valve core 11 is in contact sealing with the sealing conical surface of the orifice of the central stepped hole 3 under the action of the prepressing force of the buffer spring (10). Reverse oil enters the throttling hole 19 through the nozzle 2 and is communicated with the central stepped hole 3 and the damping hole 17 through the eccentric flow passage 18, two paths entering the buffer cavity 5 are formed, and the piston rod 8 is driven to move from left to right. Hydraulic oil enters the hydraulic cavity 9 to push the piston rod 8 to move leftwards, before the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3, oil in the buffer cavity 5 can be discharged into a flow channel of the nozzle 2 through two paths of 'the central stepped hole 3-the orifice 19' and 'the eccentric through hole 13-the eccentric stepped hole 14-the damping hole 17-the eccentric flow channel 18', the oil flow is not limited, the oil pressure in the buffer cavity 5 is not increased, no reverse thrust is generated on the piston rod 8, and no buffer exists; the piston rod 8 continues to move leftwards, the locking nut 12 is driven to enter the central stepped hole 3, the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3, the buffer valve core 11 is blocked and does not move along with the piston rod 8 any more, the buffer valve core 11 is in contact sealing with the sealing conical surface of the orifice of the central stepped hole 3 under the pre-pressure action of the buffer spring 10, a channel which is discharged into the nozzle 2 through the central stepped hole 3-the throttling hole 19 is blocked, and oil in the buffer cavity 5 can only be discharged into a flow channel of the nozzle 2 through the eccentric through hole 13-the eccentric stepped hole 14-the damping hole 17-the eccentric flow channel 18; the piston rod 8 compresses the buffer spring 10 to drive the lock nut 12 to continue to move towards the inside of the central stepped hole 3, the pressure in the buffer cavity 5 is increased under the current limiting effect of the damping hole 17, and the buffer valve core 11 is attached to the sealing conical surface of the orifice of the central stepped hole 3 more tightly under the combined action of the force of the buffer spring 10 and the hydraulic pressure of the buffer cavity 5. The hydraulic pressure in the buffer cavity 5 generates a rightward reverse thrust to the piston rod 8 to reduce the movement speed of the piston rod 8, the reverse thrust is finally balanced with a leftward load applied to the piston rod 8, and the piston rod 8 finally moves at a constant speed until the sleeve 7 is contacted with the limit washer 4 and then stops moving. In the whole process, the movement speed of the piston rod 8 is gradually reduced from an initial value to move at a constant speed at a lower speed and finally stops, the bottom collision energy of the piston rod is weakened, and the buffer is realized.

When the piston rod 8 needs to move rightwards from a left-to-bottom state, oil is reversely led from the nozzle 2, and the oil can enter the buffer cavity 5 through 3 paths, namely, the oil enters the buffer cavity 5 through the eccentric flow passage 18, the damping hole 17, the eccentric stepped hole 14 and the eccentric through hole 13; secondly, the one-way valve core 16 is pushed open by overcoming the force of the return spring 15 through the eccentric flow passage 18, and enters the buffer cavity 5 through an axial groove on the excircle surface of the one-way valve core 16, the eccentric stepped hole 14 and the eccentric through hole 13; thirdly, the damper spool 11 is pushed open into the damper chamber 5 via the orifice 19 and the center stepped hole 3 against the force of the damper spring 10. The hydraulic oil is not limited by the flow, and pushes the piston rod 8 to move rightwards.

See fig. 2. The sleeve 7 is fixedly connected to the step shaft thread of the piston rod 8, the locking nut 12 is fastened on the end thread of the valve rod of the piston rod 8, the buffer valve core 11 is sleeved on the valve rod of the piston rod 8, the buffer spring 10 is sleeved on the outer side of the buffer valve core 11, and the buffer valve core 11 and the hole opening of the central step hole 3 are both provided with sealing conical surfaces. The sleeve 7 is used for limiting the leftward movement of the piston rod 8, one side of the buffer valve core 11 is limited by the locking nut 12, the other side of the buffer valve core is limited by the force of the buffer spring 10, the buffer valve core can reciprocate on the valve rod of the piston rod 8, the moving surface of the buffer valve core is sealed, and the piston rod 8 can drive the locking nut 12 to move in the central stepped hole 3 of the end cover 1 along the axial direction.

See fig. 3. An eccentric stepped hole 14 of an end cover 1 is communicated with a flow channel of a nozzle 2 through an eccentric flow channel 18, a one-way valve core 16 arranged in the eccentric stepped hole 14 is supported by a return spring 15 and is sealed with an orifice of the eccentric flow channel 18 in a conical surface manner, a limit gasket 4 fixed between the end cover 1 and a working cylinder barrel 6 supports the return spring 15, and an eccentric through hole 13 on the limit gasket is communicated with the eccentric stepped hole 14 and the buffer cavity 5.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents. Alternatives and modifications, the scope of the utility model being defined by the appended claims and equivalents thereof.

Claims (3)

1. A hydraulic actuator end dampening buffer mechanism comprising: end cover (1) with joint bearing pilot hole and radial mouthpiece (2), with end cover (1) internal threaded connection and sealed work cylinder (6) in end cover (1) port barrel, reciprocating motion is direct at integral type variable cross section piston rod (8) of external acting in work cylinder (6), link up sleeve (7) on piston rod (8) first order step axle screw thread admittedly, fastening lock nut (12) on piston rod (8) second order cantilever valve rod end screw thread, the cover is equipped with buffer spring (10) and is retrained buffer valve core (11) between lock nut (12) and piston rod (8) valve rod outer sleeve spring seat, its characterized in that: a piston rod (8) which runs in a working cylinder barrel (6) in a sealed mode divides the working cylinder barrel (6) into a buffer cavity (5) and a hydraulic cavity (9), a flow channel of a nozzle (2) is communicated with a central step hole (3) in the middle of an end cover (1) and an eccentric step hole (14) below through a throttling hole (19) and an eccentric flow channel (18) respectively, a one-way valve core (16) and a return spring (15) are arranged in the eccentric step hole (14) and supported by a limiting gasket (4) fixed between the end cover (1) and the working cylinder barrel (6), and the eccentric step hole (14) is communicated with the buffer cavity (5) through an eccentric through hole (13) in the limiting gasket (4).

2. The hydraulic actuator end dampening buffer mechanism according to claim 1, wherein: the sleeve (7) is used for limiting the leftward movement of the piston rod (8), the buffer valve core (11) and the orifice of the central stepped hole (3) are provided with sealing conical surfaces, the buffer valve core (11) is limited by a locking nut (12), can reciprocate on the valve rod of the piston rod (8) under the force of a buffer spring (10), the moving surface of the buffer valve core is sealed, and the one-way valve core (16) and the orifice of the eccentric flow channel (18) are sealed in a conical surface mode in a free state.

3. The hydraulic actuator end dampening buffer mechanism according to claim 1, wherein: the hydraulic oil-driven hydraulic oil pump is characterized in that a buffer valve core (11) which drives a locking nut (12) to move leftwards is arranged at the front end of the hydraulic oil-driven hydraulic oil-.

Images