A stress buffering connecting structure of a hydraulic cylinder piston rod

Abstract

The utility model relates to a piston rod technical field, concretely relates to a stress buffer connecting structure of hydraulic cylinder piston rod, a stress buffer connecting structure of hydraulic cylinder piston rod, include: hydraulic cylinder barrel, the inner wall sliding connection of hydraulic cylinder barrel has hydraulic piston rod, the outer wall fixed connection of hydraulic piston rod has piston board, the outer wall of hydraulic piston rod is equipped with the buffer device, the inner wall of hydraulic cylinder barrel is equipped with the damping device, the outer wall of hydraulic piston cylinder is equipped with the anti -back flow device. Through setting buffer device, reduce stress concentration, hydraulic oil passes through double -point stress and acts on hydraulic piston rod and piston board simultaneously, disperses power transmission, protects the connecting part, through the classification buffer of buffer device, the end impact absorption of damping device, the anti -back flow of anti -back flow device's cooperation, can cope with instantaneous impact and pressure fluctuation, ensure that piston rod and piston board can be smooth stress in different movement stages.

Description

Technical Field

[0001] This utility model relates to the field of piston rod technology, and specifically to a stress buffer connection structure for a hydraulic cylinder piston rod. Background Technology

[0002] The existing hydraulic cylinder piston rod and piston plate connection structure has obvious limitations. During the ejection or return stroke, the power is mostly concentrated at the connection between the piston rod and the piston, resulting in stress concentration at the connection point. It is prone to fatigue cracks due to high-frequency impact. The buffer structure is simple, relying only on a single spring or hydraulic cushion, which cannot absorb instantaneous stress in stages. The buffering effect is poor and it is difficult to adapt to heavy-load high-frequency working conditions.

[0003] Therefore, in order to address the above-mentioned shortcomings, the present invention provides a stress buffer connection structure for hydraulic cylinder piston rods. By setting a stress reduction device, stress concentration is reduced and the connection parts are protected. Through the shock absorption device and the anti-backflow device, functions such as graded buffering, end impact absorption, and anti-backflow are achieved, thus meeting the urgent needs of various industries for stress buffering functions of hydraulic cylinder piston rods. Utility Model Content

[0004] To address the shortcomings of existing technologies, the technical solution adopted by this utility model to solve its technical problems is: a stress buffer connection structure for a hydraulic cylinder piston rod, comprising: a hydraulic cylinder barrel, a hydraulic piston rod slidably connected to the inner wall of the hydraulic cylinder barrel, a piston plate fixedly connected to the outer wall of the hydraulic piston rod, a damping device provided on the outer wall of the hydraulic piston rod, a shock-absorbing device provided on the inner wall of the hydraulic cylinder barrel, and an anti-backflow device provided on the outer wall of the hydraulic cylinder barrel.

[0005] Preferably, the damping device includes a fixed ring, a connecting rod slidably connected to the inner wall of the fixed ring, a return spring fixedly connected to the outer wall of the fixed ring, a force-bearing ring fixedly connected to the outer wall of the connecting rod, and a compression ring fixedly connected to the outer wall of the connecting rod away from the force-bearing ring. When the piston plate and hydraulic piston rod of the hydraulic cylinder perform the return stroke, high-pressure hydraulic oil enters the internal chamber of the hydraulic cylinder along a preset oil circuit. The hydraulic oil entering the hydraulic cylinder first forms an axial impact on the force-bearing ring in the damping device. The impact force causes the force-bearing ring to move towards the fixed ring along the axis of the hydraulic piston rod. During this process, the return spring sleeved on the outside of the connecting rod is compressed. The elastic potential energy of the return spring accumulates with the increase of compression, gradually absorbing the instantaneous impact energy of the hydraulic oil. The force-bearing ring further contracts under continuous force, and its outer wall directly squeezes the fixed ring. The rigid connection between the fixed ring and the hydraulic piston rod causes it to synchronously drive the hydraulic piston rod to move backward. The hydraulic piston rod then drives the piston plate to synchronously return through the end connection structure.

[0006] Preferably, the inner walls of the fixed ring, the force-bearing ring, and the compression ring are slidably connected to the inner wall of the hydraulic cylinder. The outer wall of the return spring away from the fixed ring is fixedly connected to the outer wall of the force-bearing ring. The outer wall of the compression ring is slidably connected to the outer wall of the piston plate. The force-bearing ring transmits the axial force to the compression ring through the connecting rod. Under the action of the force, the compression ring slides along the surface of the piston plate and forms a secondary impact. Combined with the diversion impact formed by the hydraulic oil passing through the annular hole between the force-bearing ring, the fixed ring, and the compression ring, the dual force ensures that the piston plate moves smoothly, and finally realizes the return stroke of the hydraulic piston rod while reducing the stress at the connection.

[0007] Preferably, the shock absorption device includes a support ring, and a damping pad is fixedly connected to the outer wall of the support ring. A return spring is fixedly connected to the outer wall of the end of the support ring away from the damping pad. When the piston plate and the hydraulic piston rod gradually approach the return limit position, the boss at the end of the hydraulic piston rod is embedded in the groove area of ​​the inner wall of the hydraulic cylinder. The inclined surface of the boss and the hydraulic oil in the groove are squeezed together. The squeezed hydraulic oil flows into the cavity at the end of the hydraulic cylinder along the groove channel. The pressure in the cavity rises sharply and pushes the sliding rod of the support ring in the shock absorption device to extend outward along the guide groove. During the movement of the sliding rod, the return spring is stretched synchronously. The tension of the return spring increases with the increase of the stretching amount, forming a reverse buffer force.

[0008] Preferably, the outer wall of the support ring is slidably connected to the inner wall of the hydraulic cylinder, and the outer wall of the return spring at the end away from the support ring is fixedly connected to the inner wall of the hydraulic cylinder. When the damping pad at the front end of the support ring is in pre-contact with the edge of the piston plate, the damping pad absorbs part of the kinetic energy through its own deformation. The support ring then applies resistance to the piston plate in the opposite direction of movement with the help of the tension of the return spring. At the same time, the piston plate squeezes the hydraulic oil on one side of the support ring, which further increases the hydraulic oil pressure in the chamber. The high-pressure oil reacts to the boss of the hydraulic piston rod, forming a hydraulic resistance in the opposite direction of movement. The two opposing forces gradually increase as the piston plate approaches, and eventually form a dynamic balance with the inertial forces of the piston plate and the hydraulic piston rod, significantly reducing the instantaneous stress at the connection between the two.

[0009] Preferably, the anti-backflow device includes an oil inlet pipe, an oil outlet pipe fixedly connected to the outer wall of the oil inlet pipe, a sealing piston slidably connected to the inner wall of the oil inlet pipe, a retaining spring fixedly connected to the outer wall of the sealing piston, and an oil discharge piston slidably connected to the inner wall of the oil outlet pipe. A limit spring is fixedly connected to the outer wall of the oil discharge piston. When the piston plate and the hydraulic piston rod are in the return stroke stage, the boss of the hydraulic piston rod and the edge of the piston plate jointly squeeze the hydraulic oil in the groove of the hydraulic cylinder. The overpressured oil flows into the oil inlet pipe of the anti-backflow device through a one-way channel. The high-pressure oil entering the oil inlet pipe overcomes the preload of the limit spring and pushes open the oil discharge piston in the oil outlet pipe connected to the oil inlet pipe. The oil discharge piston moves along the axis of the oil outlet pipe, and the hydraulic oil is quickly discharged to the oil tank through the oil outlet pipe, effectively reducing the oil pressure in the hydraulic cylinder and preventing stress concentration at the connection between the hydraulic piston rod and the piston plate due to excessive pressure, thus ensuring the safety of the return stroke.

[0010] Preferably, the outer wall of the end of the retaining spring away from the sealing piston is fixedly connected to the inner wall of the oil inlet pipe, and the outer wall of the end of the limiting spring away from the unloading piston is fixedly connected to the outer wall of the end of the oil outlet pipe. When the hydraulic cylinder drives the piston plate and hydraulic piston rod to perform the ejection action, the external high-pressure hydraulic oil is delivered to the oil inlet pipe of the anti-backflow device through the oil circuit control system. The hydraulic oil entering the oil inlet pipe first acts on the sealing piston, overcoming the elastic force of the retaining spring and pushing the sealing piston to move inward, so that the oil inlet pipe and the internal cavity of the hydraulic cylinder form a passage. After the high-pressure hydraulic oil enters the hydraulic cylinder along the passage, it forms two power flows. One flow directly impacts the boss at the end of the hydraulic piston rod, and drives the piston plate to start through the rigid connection between the boss and the hydraulic piston rod. The other flow passes over the boss and acts directly on the inner end face of the piston plate. This "dual-point force" design allows the driving force of the hydraulic oil to be simultaneously distributed on the hydraulic piston rod and the piston plate. Compared with the traditional hydraulic cylinder mode where only the piston plate is subjected to force, it alleviates fatigue damage at the connection between the hydraulic piston rod and the piston plate and extends the service life of the structure.

[0011] The beneficial effects of this utility model are as follows:

[0012] 1. This utility model reduces stress concentration and protects the connection parts by setting a damping device. During ejection, the hydraulic oil acts on the hydraulic piston rod and piston plate simultaneously through two points of force, dispersing the power transmission. During return, the damping device reduces the local stress at the connection parts by diverting the hydraulic oil through the return spring. Combined with the dynamic balance resistance of the shock absorption device, it avoids fatigue damage caused by stress concentration.

[0013] 2. This utility model adapts to complex working conditions by setting up a shock absorption device and an anti-backflow device. The graded buffering of the damping device, the end impact absorption of the shock absorption device, and the anti-backflow device work together to cope with instantaneous impacts and pressure fluctuations, ensuring that the piston rod and piston plate can be stably stressed at different stages of movement, and improving the durability of the device under heavy load and high frequency working conditions. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the internal structure of this utility model;

[0016] Figure 3 This is a schematic diagram of the piston rod of this utility model;

[0017] Figure 4 This is a schematic diagram of the structure of the deceleration device of this utility model;

[0018] Figure 5 This is a structural schematic diagram of the shock absorption device of this utility model;

[0019] Figure 6 yes Figure 5 A magnified view of a portion of point A in the middle.

[0020] In the diagram: 1. Hydraulic cylinder; 2. Hydraulic piston rod; 3. Piston plate; 4. Deceleration device; 5. Shock absorption device; 6. Anti-backflow device; 40. Fixing ring; 41. Connecting rod; 42. Return spring; 43. Force ring; 44. Compression ring; 50. Support ring; 51. Shock absorber; 52. Return spring; 60. Oil inlet pipe; 61. Oil outlet pipe; 62. Sealing piston; 63. Retention spring; 64. Oil unloading piston; 65. Limit spring. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical applications of the present invention, and to enable those skilled in the art to understand the present invention and design various embodiments with various modifications suitable for a particular purpose.

[0022] Example:

[0023] Please see Figure 1 - Figure 6This utility model provides a technical solution: a stress buffer connection structure for a hydraulic cylinder piston rod, comprising: a hydraulic cylinder 1, a hydraulic piston rod 2 slidably connected to the inner wall of the hydraulic cylinder 1, a piston plate 3 fixedly connected to the outer wall of the hydraulic piston rod 2, a damping device 4 provided on the outer wall of the hydraulic piston rod 2, a shock-absorbing device 5 provided on the inner wall of the hydraulic cylinder 1, and an anti-backflow device 6 provided on the outer wall of the hydraulic cylinder 1.

[0024] The deceleration device 4 includes a fixed ring 40, a connecting rod 41 slidably connected to the inner wall of the fixed ring 40, a return spring 42 fixedly connected to the outer wall of the fixed ring 40, a force-bearing ring 43 fixedly connected to the outer wall of the connecting rod 41, and a compression ring 44 fixedly connected to the outer wall of the end of the connecting rod 41 away from the force-bearing ring 43.

[0025] The inner walls of the fixed ring 40, the force ring 43 and the compression ring 44 are slidably connected to the inner wall of the hydraulic cylinder 1. The outer wall of the end of the return spring 42 away from the fixed ring 40 is fixedly connected to the outer wall of the force ring 43. The outer wall of the compression ring 44 is slidably connected to the outer wall of the piston plate 3.

[0026] The shock absorption device 5 includes a support ring 50, a shock-absorbing pad 51 is fixedly connected to the outer wall of the support ring 50, a return spring 52 is fixedly connected to the outer wall of the support ring 50 away from the shock-absorbing pad 51, the outer wall of the support ring 50 is slidably connected to the inner wall of the hydraulic cylinder 1, and the outer wall of the return spring 52 away from the support ring 50 is fixedly connected to the inner wall of the hydraulic cylinder 1.

[0027] The anti-backflow device 6 includes an oil inlet pipe 60, an oil outlet pipe 61 fixedly connected to the outer wall of the oil inlet pipe 60, a sealing piston 62 slidably connected to the inner wall of the oil inlet pipe 60, a retaining spring 63 fixedly connected to the outer wall of the sealing piston 62, an oil discharge piston 64 slidably connected to the inner wall of the oil outlet pipe 61, and a limit spring 65 fixedly connected to the outer wall of the oil discharge piston 64.

[0028] The outer wall of the end of the retaining spring 63 away from the sealing piston 62 is fixedly connected to the inner wall of the oil inlet pipe 60, and the outer wall of the end of the limiting spring 65 away from the unloading piston 64 is fixedly connected to the outer wall of the end of the oil outlet pipe 61.

[0029] Working principle:

[0030] When the piston plate 3 and hydraulic piston rod 2 of the hydraulic cylinder perform the return stroke, high-pressure hydraulic oil enters the internal chamber of the hydraulic cylinder 1 along the preset oil circuit. The hydraulic oil entering the hydraulic cylinder 1 first forms an axial impact on the force ring 43 in the damping device 4. The impact force causes the force ring 43 to move along the axis of the hydraulic piston rod 2 towards the fixed ring 40. During this process, the return spring 42 sleeved on the outside of the connecting rod 41 is compressed. The elastic potential energy of the return spring 42 accumulates with the increase of compression, gradually absorbing the instantaneous impact energy of the hydraulic oil. Under continuous force, the force ring 43 further contracts, and its outer wall directly squeezes the fixed ring. 40. The rigid connection between the fixed ring 40 and the hydraulic piston rod 2 enables the hydraulic piston rod 2 to move backward synchronously. The hydraulic piston rod 2 then drives the piston plate 3 to return synchronously through the end connection structure. At the same time, the force ring 43 transmits the axial force to the compression ring 44 through the connecting rod 41. Under the action of the force, the compression ring 44 slides along the surface of the piston plate 3 and forms a secondary impact. Combined with the diversion impact formed by the hydraulic oil passing through the annular hole between the force ring 43, the fixed ring 40 and the compression ring 44, the dual force ensures that the piston plate 3 moves smoothly, and finally realizes the return of the hydraulic piston rod 2 while reducing the stress at the connection.

[0031] As the piston plate 3 and hydraulic piston rod 2 gradually approach their return limit position, the boss at the end of the hydraulic piston rod 2 embeds into the groove area of ​​the inner wall of the hydraulic cylinder 1. The inclined surface of the boss and the hydraulic oil in the groove are squeezed together. The squeezed hydraulic oil flows into the cavity at the end of the hydraulic cylinder 1 along the groove channel. The pressure in the cavity rises sharply and pushes the sliding rod of the support ring 50 in the shock absorption device 5 to extend outward along the guide groove. During the movement of the sliding rod, the return spring 52 is stretched synchronously. The tension of the return spring 52 increases with the increase of the stretch, forming a reverse buffer force. When the damping pad 51 at the front end of the support ring 50 and the piston... When the edge of plate 3 is in pre-contact, the damping pad 51 absorbs part of the kinetic energy through its own deformation, while the support ring 50 applies resistance to the piston plate 3 in the opposite direction of movement with the help of the pull of the return spring 52. At the same time, the piston plate 3 squeezes the hydraulic oil on one side of the support ring 50, which further increases the hydraulic oil pressure in the chamber. The high-pressure oil reacts to the boss of the hydraulic piston rod 2, forming a hydraulic resistance in the opposite direction of movement. The two opposing forces gradually increase as the piston plate 3 approaches, and eventually form a dynamic balance with the inertial force of the piston plate 3 and the hydraulic piston rod 2, which significantly reduces the instantaneous stress at the connection between the two.

[0032] When the piston plate 3 and the hydraulic piston rod 2 are in the return stroke stage, the boss of the hydraulic piston rod 2 and the edge of the piston plate 3 together squeeze the hydraulic oil in the groove of the hydraulic cylinder 1. The overpressured oil flows into the oil inlet pipe 60 of the anti-backflow device 6 through the one-way channel. The high-pressure oil entering the oil inlet pipe 60 overcomes the preload of the limit spring 65 and pushes open the oil discharge piston 64 in the oil outlet pipe 61 connected to the oil inlet pipe 60. The oil discharge piston 64 moves along the axis of the oil outlet pipe 61, and the hydraulic oil is quickly discharged to the oil tank through the oil outlet pipe 61, effectively reducing the oil pressure in the hydraulic cylinder 1 and preventing stress concentration at the connection between the hydraulic piston rod 2 and the piston plate 3 due to excessive pressure on the piston plate 3, thus ensuring the safety of the return stroke process.

[0033] When the hydraulic cylinder drives the piston plate 3 and the hydraulic piston rod 2 to perform the ejection action, the external high-pressure hydraulic oil is delivered to the oil inlet pipe 60 of the anti-backflow device 6 through the oil circuit control system. The hydraulic oil entering the oil inlet pipe 60 first acts on the sealing piston 62, overcoming the elastic force of the retaining spring 63 and pushing the sealing piston 62 to move inward, so that the oil inlet pipe 60 and the internal cavity of the hydraulic cylinder 1 form a passage. After the high-pressure hydraulic oil enters the hydraulic cylinder 1 along the passage, it forms two power flows. One flow directly impacts the boss at the end of the hydraulic piston rod 2, and drives the piston plate 3 to start through the rigid connection between the boss and the hydraulic piston rod 2. The other flow passes over the boss and acts directly on the inner end face of the piston plate 3. This "dual-point force" design makes the driving force of the hydraulic oil simultaneously distributed on the hydraulic piston rod 2 and the piston plate 3. Compared with the traditional hydraulic cylinder mode of only bearing force through the piston plate 3, it alleviates fatigue damage at the connection between the hydraulic piston rod 2 and the piston plate 3 and extends the service life of the structure.

[0034] Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of this utility model without creative effort should fall within the protection scope of this utility model. Structures, devices, and operating methods not specifically described and explained in this utility model, unless otherwise specified or limited, shall be implemented according to conventional means in the art.

Claims

1. A stress-relief connection structure for a hydraulic cylinder piston rod, comprising: A hydraulic cylinder (1) is characterized in that a hydraulic piston rod (2) is slidably connected to the inner wall of the hydraulic cylinder (1), a piston plate (3) is fixedly connected to the outer wall of the hydraulic piston rod (2), a damping device (4) is provided on the outer wall of the hydraulic piston rod (2), a shock-absorbing device (5) is provided on the inner wall of the hydraulic cylinder (1), and an anti-backflow device (6) is provided on the outer wall of the hydraulic cylinder (1).

2. The stress buffer connection structure for a hydraulic cylinder piston rod according to claim 1, characterized in that: The deceleration device (4) includes a fixed ring (40), a connecting rod (41) is slidably connected to the inner wall of the fixed ring (40), a return spring (42) is fixedly connected to the outer wall of the fixed ring (40), a force-bearing ring (43) is fixedly connected to the outer wall of the connecting rod (41), and a compression ring (44) is fixedly connected to the outer wall of the end of the connecting rod (41) away from the force-bearing ring (43).

3. The stress buffer connection structure for a hydraulic cylinder piston rod according to claim 2, characterized in that: The inner walls of the fixed ring (40), the force ring (43) and the compression ring (44) are slidably connected to the inner wall of the hydraulic cylinder (1). The outer wall of the end of the return spring (42) away from the fixed ring (40) is fixedly connected to the outer wall of the force ring (43). The outer wall of the compression ring (44) is slidably connected to the outer wall of the piston plate (3).

4. The stress buffer connection structure for a hydraulic cylinder piston rod according to claim 1, characterized in that: The shock absorption device (5) includes a support ring (50), a shock-absorbing pad (51) is fixedly connected to the outer wall of the support ring (50), and a return spring (52) is fixedly connected to the outer wall of the end of the support ring (50) away from the shock-absorbing pad (51).

5. The stress buffer connection structure for a hydraulic cylinder piston rod according to claim 4, characterized in that: The outer wall of the support ring (50) is slidably connected to the inner wall of the hydraulic cylinder (1), and the outer wall of the return spring (52) away from the support ring (50) is fixedly connected to the inner wall of the hydraulic cylinder (1).

6. The stress buffer connection structure for a hydraulic cylinder piston rod according to claim 1, characterized in that: The anti-backflow device (6) includes an oil inlet pipe (60), an oil outlet pipe (61) is fixedly connected to the outer wall of the oil inlet pipe (60), a sealing piston (62) is slidably connected to the inner wall of the oil inlet pipe (60), a retaining spring (63) is fixedly connected to the outer wall of the sealing piston (62), an oil discharge piston (64) is slidably connected to the inner wall of the oil outlet pipe (61), and a limit spring (65) is fixedly connected to the outer wall of the oil discharge piston (64).

7. The stress buffer connection structure for a hydraulic cylinder piston rod according to claim 6, characterized in that: The outer wall of the end of the retaining spring (63) away from the sealing piston (62) is fixedly connected to the inner wall of the oil inlet pipe (60), and the outer wall of the end of the limiting spring (65) away from the unloading piston (64) is fixedly connected to the outer wall of the end of the oil outlet pipe (61).

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