Heavy-load impact rod hydrostatic bearing device and impact cylinder

Abstract

The invention discloses a heavy-load impact rod hydrostatic bearing device and an impact cylinder, and relates to the technical field of large impact equipment, the heavy-load impact rod hydrostatic bearing device comprises a hydrostatic bearing body, the hydrostatic bearing body is uniformly provided with an even number (not less than 4) of pressure oil cavities along the circumferential direction of the inner hole wall, and the pressure oil cavities are symmetrically arranged along the axial center of the hydrostatic bearing body; the two sides of the pressure oil cavity in the axial direction are each provided with a first oil return annular groove at equal intervals, damping annular seams are formed among the first oil return annular grooves, the pressure oil cavity and the outer wall of the impact rod, the two first oil return annular grooves are connected with an external oil tank used for oil storage through oil return channels, and the pressure oil cavity is provided with damping structures in a communicated mode. Damping holes are formed in the damping structure, the pressure oil cavities are communicated with an external pressure oil source through the damping holes, when the impact rod is subjected to radial loads, the thrust of the pressure oil cavity on the side with the smaller gap to the impact rod is increased, the balance thrust of the pressure oil cavity on the side with the larger gap to the impact rod is reduced, and the impact rod is automatically reset to the center position.

Description

Technical Field

[0001] The present application relates to the technical field of large impact devices, and in particular to a static pressure bearing device for a heavy-duty impact rod and an impact cylinder. Background Art

[0002] For large high-speed heavy-duty impact devices, their impact speed is much higher than that of ordinary impactors. The action execution element for impact is an impact cylinder, which includes a cylinder body and an impact rod that slides within the cylinder body. During the impact process, the radial load borne by the impact rod is also very large. The impact rod moves at high speed within the cylinder body. The friction of the piston rod of an ordinary impact cylinder is large, which is not conducive to obtaining a high impact speed, and it is extremely easy to damage the impact cylinder when bearing radial impact loads. Especially in the working condition where the impact rod directly impacts the workpiece with an impact head, the impact rod bears severe axial and radial loads, and often the impact rod deforms and the surface is scratched within the cylinder guide sleeve, resulting in hindered telescoping of the impact rod and seal leakage. In severe cases, it even leads to serious consequences such as bending and breaking of the impact rod.

[0003] If a static pressure bearing can achieve liquid friction, it can greatly reduce the operating friction resistance and the power consumption of useless work, and can bear a large load. However, some static pressure bearings in conventional technologies are only used for the rotational motion of the shaft. The shaft has no axial movement within the bearing, the working positions of the shaft and the bearing are relatively fixed, and it only bears loads in a certain direction on the circumference. Most large static pressure bearings are not a complete closed circumference in the circumferential direction. Such static pressure bearings cannot meet the working condition requirements of the impact rod with loads in any circumferential direction.

[0004] For the existing static pressure bearing solutions for impactor design, their automatic centering adjustment scheme uses film feedback. It is very difficult for the feedback pressure-displacement mechanical parameters of the film to form an adaptable change relationship with the oil pressure change caused by the eccentricity of the impact rod. As a result, it is difficult for the feedback adjustment to reach a stable equilibrium position, and it is very likely to either have an adjustment oscillation phenomenon or the feedback centering effect is not obvious, failing to achieve the preset control purpose and not being able to achieve the stable automatic centering adjustment function of the impact rod.

[0005] In summary, using existing conventional technologies cannot meet the working requirements of a high-speed gas-liquid impact test system. Therefore, there is a need for an impact rod bearing that can bear radial variable loads during the impact process of the axial high-speed movement of the impact rod. This bearing can achieve stable liquid friction, reduce the friction resistance, avoid scratching the impact rod, and has the ability to automatically center against external radial loads when the impact rod deviates from the center within the bearing and presses against the bearing wall due to radial load interference. Summary of the Invention

[0006] In order to help solve the problem of being able to bear radial heavy loads during the impact process of the axial high-speed movement of the impact rod, the present application provides a static pressure bearing device for a heavy-duty impact rod and an impact cylinder.

[0007] In a first aspect, the present application provides a static pressure bearing device for a heavy-duty impact rod, adopting the following technical solution: A static pressure bearing device for a heavy-duty impact rod includes a static pressure bearing body. The static pressure bearing body is circumferentially and uniformly provided with an even number of pressure oil cavities not less than 4 along the inner hole wall. The pressure oil cavities are symmetrically arranged along the axial center of the static pressure bearing body. On both sides of the pressure oil cavities along the axial direction, a first oil return ring groove is provided at the same interval. A damping ring gap connecting the first oil return ring groove and the pressure oil cavity is formed between the inner hole wall of the static pressure bearing body between the two first oil return ring grooves and the outer wall of the impact rod for impact. The two first oil return ring grooves are connected to an external oil tank for storing oil through an oil return channel. The even number of pressure oil cavities not less than 4 are respectively connected with damping structures, and damping holes are provided on the damping structures. The even number of pressure oil cavities not less than 4 are respectively connected to an external pressure oil source through the damping holes.

[0008] By adopting the above technical solution, when the impact rod is not subjected to an external radial load, the thrust of the oil in each pressure oil cavity on the impact rod is symmetric and equal, and the impact rod is in a dynamic balance state at the central position of the static pressure bearing body. When the impact rod is subjected to a radial load, the gap of the damping ring gap on the side bearing the load becomes larger, and the gap on the opposite side becomes smaller. The flow area of the damping ring gap leading to the first oil return ring groove in the pressure oil cavity with a smaller gap decreases, the flow resistance of the oil passage of this side damping ring gap increases, and the flow rate through this side damping ring gap decreases, resulting in a decrease in the flow rate through the damping structure of this oil passage. The pressure drop at both ends of the damping structure connected to this pressure oil cavity decreases, that is, the oil pressure difference between the pressure oil cavity P L and the oil supply pressure P P decreases. Under the condition that the oil supply pressure P P and the oil return pressure P 0 remain unchanged, the oil pressure P L in the pressure oil cavity increases, the thrust of the pressure oil cavity on the side with a smaller gap on the impact rod increases, resisting the load and causing the impact rod to reset to the central position. Similarly, the flow area of the damping ring gap on the side with a larger gap increases, the flow resistance of the oil passage of this side damping ring gap decreases, and the flow rate leading to this side damping ring gap increases, resulting in an increase in the flow rate through the damping structure of the oil passage leading to this side pressure oil cavity. The pressure drop at both ends of the damping structure increases, that is, the oil pressure difference between the pressure oil cavity P L and the oil supply pressure P P increases. Under the condition that the oil supply pressure P P and the oil return pressure P 0 remain unchanged, the oil pressure P LIt will inevitably decrease. The balance thrust of the pressure oil chamber on the side with the increased gap against the impact rod decreases, which also causes the impact rod to reset to the central position. Through the opposite changes in the thrusts of the two pressure oil chambers, the impact rod can resist radial loads, achieving the function of automatic centering control, and reliably ensuring that the relative movement between the impact rod and the hydrostatic bearing body is non-contact liquid friction.

[0009] Preferably, the damping structure is an oil inlet passage provided on the outer wall of the hydrostatic bearing body and communicating with the pressure oil chamber. A damping plug is installed on the oil inlet passage, and the damping hole is provided on the damping plug. One end of the oil inlet passage away from the pressure oil chamber is circumferentially communicated with a pressure oil ring groove along the outer wall of the hydrostatic bearing body, and the pressure oil ring groove is connected to a pressure oil passage on the impact cylinder body for installing the hydrostatic bearing body and communicating with an external pressure oil source.

[0010] By adopting the above technical solution, the pressure oil ring groove is provided on the outer wall of the hydrostatic bearing body, which helps each oil inlet passage corresponding to the pressure oil chamber to communicate with the external pressure oil source. The damping plug is installed on the oil inlet passage, and thus the pressure of the pressure oil chamber can be better adjusted, realizing the reset of the impact rod to the central position.

[0011] Preferably, a reduced-diameter oil passage is provided at one end of the oil inlet passage close to the pressure oil chamber, a threaded hole is provided at one end of the reduced-diameter oil passage away from the pressure oil chamber, the damping plug is hermetically and fixedly connected to the threaded hole, and the pore structures and diameters of the damping holes of each damping plug are the same.

[0012] By adopting the above technical solution, the reduced-diameter oil passage is provided close to the pressure oil chamber and has a diameter smaller than that of the oil inlet passage, which helps to provide a threaded hole on the reduced-diameter oil passage, facilitating the installation and disassembly of the damping plug, improving the convenience of installation, disassembly and maintenance of the damping plug. The pore structures and diameters of the damping holes are the same, which helps to make each pressure oil chamber have a consistent damping adjustment effect.

[0013] Preferably, the oil return passage is a first transverse oil return passage respectively communicating with the first oil return ring groove transversely, a longitudinal oil return passage communicating with the two first transverse oil return passages at both ends, a second oil return ring groove is provided on the outer wall of the hydrostatic bearing body, the second oil return ring groove is connected to the longitudinal oil return passage through a second transverse oil return passage, and the second oil return ring groove is connected to an external oil tank through a transition oil return passage on the impact cylinder body.

[0014] By adopting the above technical solution, the reflux oil liquid in the damping ring gap first passes through the two first oil return ring grooves, then flows through the first transverse oil return passage to the longitudinal oil return passage, and then flows from the longitudinal oil return passage through the second transverse oil return passage to the second oil return ring groove, and finally is connected to the external oil tank through the transition oil return passage on the impact cylinder body, enabling the oil liquid in the damping ring gap to flow back to the oil tank and realizing the flow circulation of the damping ring gap.

[0015] Preferably, the hydrostatic bearing device further includes a fixed sealing assembly, which includes a first fixed seal, a second fixed seal, and a third fixed seal. A first seal groove and a second seal groove are provided on both sides of the pressure oil ring groove. A third seal groove is provided on one side of the second seal groove away from the first seal groove. The second oil return ring groove is provided between the second seal groove and the third seal groove. The first fixed seal, the second fixed seal, and the third fixed seal are sequentially installed in the first seal groove, the second seal groove, and the third seal groove.

[0016] By adopting the above technical solution, by installing the first fixed seal and the second fixed seal in the first seal groove and the second seal groove respectively, it helps to reduce the leakage of the hydraulic oil in the pressure oil ring groove from the first fixed seal and the second fixed seal to both ends. By installing the third fixed seal in the third seal groove, it helps to reduce the leakage of the hydraulic oil in the second oil return ring groove from the second fixed seal and the third fixed seal to both ends, ensuring the normal operation of the hydraulic oil circuit.

[0017] Preferably, the hydrostatic bearing device further includes a sliding sealing assembly, which includes two sliding seals. A sliding seal groove is provided on the inner hole wall of the first oil return ring groove near the end of the hydrostatic bearing body. The sliding seal is installed in the sliding seal groove.

[0018] By adopting the above technical solution, the sliding seal groove is provided on one side of the first oil return ring groove near the end of the hydrostatic bearing body, which helps to prevent the hydraulic oil in the rod chamber of the impact cylinder from leaking into the first oil return ring groove, or the hydraulic oil in the first oil return ring groove from leaking out from the end of the hydrostatic bearing body, improving the working stability of the hydraulic oil in the first oil return ring groove.

[0019] In a second aspect, the present application provides an impact cylinder, adopting the following technical solution: An impact cylinder includes an impact cylinder body, an impact rod, and the above-mentioned heavy-duty impact rod hydrostatic bearing device located between the impact cylinder body and the impact rod, and further includes a fixing assembly for fixing the hydrostatic bearing body and the impact cylinder body.

[0020] By adopting the above technical solution, the impact cylinder fixes the hydrostatic bearing body and the impact cylinder body together through the fixing assembly, which helps to prevent the hydrostatic bearing body from axially moving along the impact rod, improving the working reliability of the hydrostatic bearing device.

[0021] Preferably, the fixing assembly includes a cylinder head, which is provided with a through hole through which the impact rod passes. One end of the cylinder head close to the impact cylinder body abuts and is fixedly connected to the end of the impact cylinder body. The hydrostatic bearing body is fixedly connected to the cylinder head.

[0022] By adopting the above technical solution, the fixing component helps to improve the firmness of the installation of the hydrostatic bearing body by mounting the cylinder head at one end of the impact cylinder block and then fixedly connecting the hydrostatic bearing body to the cylinder head.

[0023] Preferably, the fixing component further includes a plurality of keyways. An annular keyway is provided at one end of the impact cylinder block close to the cylinder head. The plurality of keyways are installed in the annular keyway. A reduced-diameter portion is provided at one end of the hydrostatic bearing body close to the cylinder head. A step is formed between the reduced-diameter portion and the outer wall of the hydrostatic bearing body. One end of the keyway away from the cylinder head abuts against the step. A thrust ring is integrally provided on one side of the cylinder head close to the keyway. One end of the thrust ring close to the keyway abuts against one end of the keyway close to the cylinder head.

[0024] By adopting the above technical solution, the fixing component improves the impact force borne by the hydrostatic bearing body along the axial direction of the impact rod by installing a plurality of keyways in the annular keyway of the impact cylinder block and abutting one end of the keyway against the step of the hydrostatic bearing body. In addition, by providing a thrust ring on the cylinder head to abut against the lower end surface of the keyway, the axial force borne by the hydrostatic bearing body is further increased, thereby improving the working reliability of the hydrostatic bearing body.

[0025] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application has the function of enabling good alignment between the impact rod and the hydrostatic bearing body, has the effect of resisting the interference of the radial load on the alignment position of the impact rod, can reliably ensure the relative movement between the impact rod and the hydrostatic bearing body to achieve liquid friction, greatly reduces the movement friction resistance and the power consumption of useless work, reduces the wear of the impact rod and the bearing, prolongs the service life of the equipment, reduces the probability of equipment damage, and has a simple structure, stable performance, reliable and durable, long service life, providing a beneficial solution for the design and manufacture of heavy-duty rod-type motion mechanisms; 2. A pressure oil ring groove is provided on the outer wall of the hydrostatic bearing body, which helps each pressure oil chamber to communicate with an external pressure oil source through an oil inlet passage. A damping plug is installed on the oil inlet passage, thereby better adjusting the pressure of the pressure oil chamber and realizing the reset of the impact rod to the central position.

[0026] 3. The oil at both ends of the damping ring gap first passes through the first oil return ring groove, then flows through the first transverse oil return passage to the longitudinal oil return passage, and then flows through the longitudinal oil return passage through the second transverse oil return passage to the second oil return ring groove, and finally is connected to an external oil tank through the transition oil return passage on the impact cylinder block, enabling the oil at both ends in the damping ring gap to flow back to the oil tank.

[0027] 4. The fixing component installs several clamping keys in the annular keyway of the impact cylinder block. One end of several clamping keys abuts against the step of the hydrostatic bearing body, improving the impact force that the hydrostatic bearing body can bear along the axial direction of the impact rod. Additionally, the thrust ring integrally provided on the cylinder head abuts against the lower end surface of the clamping key, further increasing the axial force borne by the hydrostatic bearing body, thereby enhancing the working reliability of the hydrostatic bearing body. Description of the Drawings

[0028] Figure 1 Fig. is a sectional view of a heavy-duty impact rod hydrostatic bearing device disclosed in the present application, with the sectional plane passing through the pressure oil chamber.

[0029] Figure 2 Fig. is a sectional view of a heavy-duty impact rod hydrostatic bearing device disclosed in the present application, with the sectional plane passing through the oil return passage.

[0030] Figure 3 is the sectional view along Figure 1 line A-A in

[0031] Figure 4 is the Figure 3 partial enlarged view at position I in

[0032] Figure 5 is the sectional view along Figure 2 line B-B in

[0033] Description of the Reference Numerals: 1. Hydrostatic bearing body; 11. Pressure oil chamber; 12. Pressure oil ring groove; 13. First oil return ring groove; 14. Oil inlet passage; 141. Reduced-diameter oil passage; 1411. Threaded hole; 142. Damping plug; 1421. Damping hole; 15. Oil return passage; 151. First transverse oil return passage; 152. Longitudinal oil return passage; 153. Second oil return ring groove; 154. Second transverse oil return passage; 161. First sealing groove; 162. Second sealing groove; 163. Third sealing groove; 17. Sliding sealing groove; 18. Step; 2. Damping ring gap; 3. Fixed sealing component; 31. First fixed sealing member; 32. Second fixed sealing member; 33. Third fixed sealing member; 4. Sliding sealing component; 41. Sliding sealing member; 5. Impact cylinder block; 51. Pressure oil passage; 52. Transition oil return passage; 53. Annular keyway; 6. Impact rod; 7. Fixing component; 71. Cylinder head; 711. Thrust ring; 72. Clamping key. Detailed Embodiment

[0034] The following Figures 1 to 5 further elaborates on the present application in detail.

[0035] The embodiment of the present application discloses a heavy-duty impact rod hydrostatic bearing device.

[0036] An overloaded impact rod hydrostatic bearing device. Refer to Figure 1 and Figure 2 , including a hydrostatic bearing body 1. Along the inner hole wall of the hydrostatic bearing body 1, there are evenly distributed no less than 4 even-numbered pressure oil cavities 11 in the circumferential direction. In the embodiment of the present application, the number of pressure oil cavities 11 is 4. In other embodiments of the present application, the number of pressure oil cavities 11 is 6 and 8. The number of pressure oil cavities 11 is related to the inner hole diameter of the hydrostatic bearing. For a larger diameter, a larger number of pressure oil cavities 11 can be selected. The pressure oil cavities 11 are symmetrically arranged along the axial center of the hydrostatic bearing body 1. On both sides of the pressure oil cavity 11 along the axial direction, there is a first oil return ring groove 13 at the same interval. Between the two first oil return ring grooves 13 and the inner hole wall of the hydrostatic bearing body 1 among no less than 4 even-numbered pressure oil cavities 11, and between the outer wall of the impact rod 6 for impact, a damping ring gap 2 connecting the first oil return ring groove 13 and the pressure oil cavity 11 is formed. The two first oil return ring grooves 13 are connected to an external oil tank for storing oil through an oil return channel 15. Each of the no less than 4 even-numbered pressure oil cavities 11 is respectively connected with a damping structure, and a damping hole 1421 is provided on the damping structure. Each of the no less than 4 even-numbered pressure oil cavities 11 is respectively connected to an external pressure oil source through the damping hole 1421; it should be noted that the shape of the pressure oil cavity 11 when unfolded in the circumferential direction can be rectangular or circular, and the axial cross-section can be rectangular or crescent-shaped. The pressure oil cavity 11 has a certain thickness in the radial direction, and the pressure oil can flow freely in the pressure oil cavity 11. The size of the gap of the damping ring gap 2 and the size of the damping hole 1421 are related to the radial load, oil supply pressure and flow rate.

[0037] In the embodiment of the present application, the impact rod 6 is installed in the inner hole of the hydrostatic bearing body 1. One end of the impact rod 6 installed in the impact cylinder body 5 is connected to an impact piston, and the other end is installed with an impact head for impact. In other embodiments of the present application, it is a piston rod. The impact rod 6 or the piston rod can bear an overloaded axial force along the axial direction, and the overloaded load exceeds more than one hundred tons. During the impact process, when the impact rod 6 is not subjected to an external radial load, the thrust of the oil in each pressure oil cavity 11 on the impact rod 6 is symmetric and equal, and the impact rod 6 is in a dynamic balance state at the central position of the hydrostatic bearing body 1. When the impact rod 6 is subjected to a radial load during the movement process, the gap of the damping ring gap 2 on the side bearing the load becomes larger, and the gap on the opposite side becomes smaller. The flow area of the damping ring gap 2 leading from the pressure oil cavity 11 on the side with the smaller gap to the first oil return ring groove 13 decreases, the flow resistance of the oil passage of this side damping ring gap 2 increases, and the flow rate through this side damping ring gap 2 decreases, resulting in a decrease in the flow rate through the damping structure of this oil passage. The pressure drop at both ends of the damping structure connected to this pressure oil cavity 11 decreases, that is, the oil pressure P L of the pressure oil cavity 11 and the oil supply pressure P P The oil pressure difference between them decreases. Under the condition that the oil supply pressure P P and the oil return pressure P 0 remain unchanged, it causes the oil pressure P in the pressure oil cavity 11 to decrease.L rises, the thrust of the pressure oil chamber 11 on the side with the smaller clearance against the impact rod 6 increases, resisting the load and resetting the impact rod 6 towards the central position. Similarly, the flow area of the damping ring gap 2 on the side with the larger clearance increases, the flow resistance of the oil passage of the damping ring gap 2 on this side decreases, the flow rate to the damping ring gap 2 on this side increases, resulting in an increase in the flow rate to the oil passage damping structure of the pressure oil chamber 11 on this side, and an increase in the pressure drop across both ends of the damping structure, that is, the oil pressure P of the pressure oil chamber 11 on this side L and the supply oil pressure P P increases, between the supply oil pressure P P and the return oil pressure P 0 remaining unchanged, the oil pressure P in the pressure oil chamber 11 on this side L will necessarily decrease, the balancing thrust of the pressure oil chamber 11 on the side with the larger clearance against the impact rod 6 decreases, also causing the impact rod 6 to reset towards the central position. Through the opposite changes in the thrusts of the pressure oil chambers 11 on both sides, the impact rod 6 can resist radial loads, realizing the automatic centering control function, and reliably ensuring that the relative movement between the impact rod 6 and the hydrostatic bearing body 1 is non-contact liquid friction.

[0038] Referring to Figure 3 and Figure 4 , the damping structure is an oil inlet passage 14 provided on the outer wall of the hydrostatic bearing body 1 and communicating with the pressure oil chamber 11. A damping plug 142 is installed on the oil inlet passage 14, and a damping hole 1421 is provided on the damping plug 142. One end of the oil inlet passage 14 far from the pressure oil chamber 11 is circumferentially connected along the outer wall of the hydrostatic bearing body 1 to form a pressure oil ring groove 12, and the pressure oil ring groove 12 is connected to a pressure oil passage 51 on the impact cylinder body 5 for installing the hydrostatic bearing body 1 and communicating with an external pressure oil source; the outer wall of the hydrostatic bearing body 1 is provided with the pressure oil ring groove 12, which helps each oil inlet passage 14 corresponding to the pressure oil chamber 11 to communicate with the external pressure oil source. The damping plug 142 is installed on the oil inlet passage 14, thereby better regulating the size of the pressure in the pressure oil chamber 11 and realizing the automatic reset of the impact rod 6 towards the central position.

[0039] Referring to Figure 4 , a reduced-diameter oil passage 141 is provided at one end of the oil inlet passage 14 close to the pressure oil chamber 11, a threaded hole 1411 is provided at one end of the reduced-diameter oil passage 141 far from the pressure oil chamber 11, and the damping plug 142 is hermetically and fixedly connected to the threaded hole 1411. The pore structures and diameters of the damping holes 1421 of each damping plug 142 are the same; the reduced-diameter oil passage 141 is provided close to the pressure oil chamber 11 and has a diameter smaller than that of the oil inlet passage 14, which helps to provide the threaded hole 1411 on the reduced-diameter oil passage 141, facilitating the installation and removal of the damping plug 142, improving the convenience of installation, removal and maintenance of the damping plug 142, and the same pore structures and diameters of the damping holes 1421 help to make each pressure oil chamber 11 have a consistent damping adjustment effect.

[0040] Referring toFigure 2 and Figure 5 , the oil return passage 15 includes a first transverse oil return passage 151 that is horizontally connected to the first oil return ring groove 13 respectively, a longitudinal oil return passage 152 with both ends connected to two first transverse oil return passages 151 respectively. A second oil return ring groove 153 is provided on the outer wall of the hydrostatic bearing body 1. The second oil return ring groove 153 is connected to the longitudinal oil return passage 152 through a second transverse oil return passage 154. The second oil return ring groove 153 is connected to an external oil tank through a transition oil return passage 52 on the impact cylinder body 5; the reflux oil of the damping ring gap 2 first passes through the two first oil return ring grooves 13, then flows through the first transverse oil return passage 151 to the longitudinal oil return passage 152, and then flows from the longitudinal oil return passage 152 through the second transverse oil return passage 154 to the second oil return ring groove 153, and finally is connected to the external oil tank through the transition oil return passage 52 on the impact cylinder body 5, which can make the oil in the damping ring gap 2 flow back to the oil tank and realize the flow circulation of the damping ring gap 2. It should be noted that when machining the first transverse oil return passage 151, for the convenience of machining, the first transverse oil return passage 151 can be drilled through along the radial direction of the hydrostatic bearing body 1, and then plugged at the inlet end of the drilled hole. Similarly, for the convenience of machining the longitudinal oil return passage 152, the longitudinal oil return passage 152 can be drilled along the axial direction of the hydrostatic bearing body 1, and then plugged at the inlet end of the drilled hole.

[0041] Refer to Figure 1 and Figure 2 , the hydrostatic bearing device further includes a fixed sealing assembly 3. The fixed sealing assembly 3 includes a first fixed seal 31, a second fixed seal 32 and a third fixed seal 33. The structures of the three fixed seals are the same. A first seal groove 161 and a second seal groove 162 are provided on both sides of the pressure oil ring groove 12. A third seal groove 163 is provided on the side of the second seal groove 162 away from the first seal groove 161. The second oil return ring groove 153 is arranged between the second seal groove 162 and the third seal groove 163. The first fixed seal 31, the second fixed seal 32 and the third fixed seal 33 are sequentially installed in the first seal groove 161, the second seal groove 162 and the third seal groove 163; by installing the first fixed seal 31 and the second fixed seal 32 in the first seal groove 161 and the second seal groove 162 respectively, it helps to reduce the leakage of the hydraulic oil in the pressure oil ring groove 12 from the first fixed seal 31 and the second fixed seal 32 to both ends. By installing the third fixed seal 33 in the third seal groove 163, it helps to reduce the leakage of the hydraulic oil in the second oil return ring groove 153 from the second fixed seal 32 and the third fixed seal 33 to both ends, ensuring the normal operation of the hydraulic oil circuit.

[0042] Refer to Figure 1, the hydrostatic bearing device further includes a sliding seal assembly 4. The sliding seal assembly 4 includes two sliding seals 41. On the inner hole wall of the first oil return ring groove 13 near one end of the hydrostatic bearing body 1, there is a sliding seal groove 17 provided respectively. The sliding seals 41 are installed in the sliding seal grooves 17, and the sliding seals 41 are allowed to have a small amount of radial elastic displacement along with the impact rod 6 in the seal grooves; the sliding seal grooves 17 are arranged on one side of the first oil return ring groove 13 near the end of the hydrostatic bearing body 1, which helps to prevent the hydraulic oil in the rod chamber of the impact cylinder body 5 from leaking into the first oil return ring groove 13, or the hydraulic oil in the first oil return ring groove 13 from leaking out from the end of the hydrostatic bearing body 1, improving the working stability of the hydraulic oil in the first oil return ring groove 13.

[0043] The embodiment of the present application also discloses an impact cylinder.

[0044] An impact cylinder, referring to Figure 2 , includes an impact cylinder body 5, an impact rod 6, and the above-mentioned heavy-duty impact rod hydrostatic bearing device located between the impact cylinder body 5 and the impact rod 6, and further includes a fixing assembly 7 for fixing the hydrostatic bearing body 1 and the impact cylinder body 5; the impact cylinder fixes the hydrostatic bearing body 1 and the impact cylinder body 5 together through the fixing assembly 7, which helps to prevent the axial movement of the hydrostatic bearing body 1 along the impact rod 6 and improves the working reliability of the hydrostatic bearing device.

[0045] Referring to Figure 2 , the fixing assembly 7 includes a cylinder head 71. The cylinder head 71 is provided with a through hole through which the impact rod 6 passes. One end of the cylinder head 71 close to the impact cylinder body 5 abuts and is fixedly connected to the end of the impact cylinder body 5, and the hydrostatic bearing body 1 is fixedly connected to the cylinder head 71; the fixing assembly 7 fixes and installs the cylinder head 71 at one end of the impact cylinder body 5 through screws, and then fixes and connects the hydrostatic bearing body 1 and the cylinder head 71 together through screws, which helps to improve the firmness of the installation of the hydrostatic bearing body 1.

[0046] Referring to Figure 2, the fixing component 7 further includes a plurality of keyways 72. An annular keyway 53 is provided at one end of the impact cylinder block 5 close to the cylinder head 71. The plurality of keyways 72 are installed in the annular keyway 53. A reduced-diameter portion is provided at one end of the hydrostatic bearing body 1 close to the cylinder head 71. A step 18 is formed between the reduced-diameter portion and the outer wall of the hydrostatic bearing body 1. The end of the keyway 72 away from the cylinder head 71 abuts against the step 18. A thrust ring 711 is integrally provided on one side of the cylinder head 71 close to the keyway 72. The end of the thrust ring 711 close to the keyway 72 abuts against the end of the keyway 72 close to the cylinder head 71. By installing the plurality of keyways 72 in the annular keyway 53 of the impact cylinder block 5 and making one end of the keyway 72 abut against the step 18 of the hydrostatic bearing body 1, the impact force borne by the hydrostatic bearing body 1 along the axis of the impact rod 6 is increased. In addition, by making the thrust ring 711 provided on the cylinder head 71 abut against the lower end surface of the keyway 72, the axial force borne by the hydrostatic bearing body 1 is further increased, thereby improving the working reliability of the hydrostatic bearing body 1.

[0047] The working principle of an impact cylinder according to an embodiment of the present application is as follows: The pressure oil passage 51 on the impact cylinder block 5 is connected to an external pressure oil source, and the transition oil return passage 52 is connected to an external oil tank. During the impact process of the impact rod 6, when the impact rod 6 is not subjected to an external radial load, the thrusts of the oil in each pressure oil chamber 11 on the impact rod 6 are symmetric and equal, and the impact rod 6 is in a dynamic balance state at the central position of the hydrostatic bearing body 1. When the impact rod 6 is subjected to a radial load during the impact process, the gap of the damping ring gap 2 on the side bearing the load becomes larger, and the gap on the opposite side becomes smaller. The flow area of the damping ring gap 2 leading from the pressure oil chamber 11 on the side with a smaller gap to the first oil return ring groove 13 decreases, the flow resistance of the oil passage of this side damping ring gap 2 increases, and the flow rate through this side damping ring gap 2 decreases, resulting in a decrease in the flow rate through the oil damping hole 1421 of this oil passage. The pressure drop at both ends of the damping hole 1421 connected to this pressure oil chamber 11 decreases, that is, the oil pressure P L of the pressure oil chamber 11 and the supply oil pressure P P The oil pressure difference between them decreases. Under the condition that the supply oil pressure P P and the return oil pressure P 0 remain unchanged, it causes the oil pressure P L in the pressure oil chamber 11 to increase. The thrust of the pressure oil chamber 11 on the side with a smaller gap on the impact rod 6 increases, resisting the load and causing the impact rod 6 to reset to the central position. Similarly, the flow area of the damping ring gap 2 on the side with a larger gap increases, the flow resistance of the oil passage of this side damping ring gap 2 decreases, and the flow rate leading to this side damping ring gap 2 increases, resulting in an increase in the flow rate through the oil damping hole 1421 of the oil passage leading to this side pressure oil chamber 11. The pressure drop at both ends of the damping hole 1421 increases, that is, the oil pressure P L of this side pressure oil chamber 11 and the supply oil pressure P P The oil pressure difference between them increases. Under the condition that the supply oil pressure P P and the return oil pressure P 0Under the unchanged conditions, the oil pressure P in the pressure oil chamber 11 on this side L will necessarily decrease. The balance thrust of the pressure oil chamber 11 on the side with the increased clearance against the impact rod 6 decreases, which also causes the impact rod 6 to reset to the central position. Through the opposite changes in the thrusts of the pressure oil chambers 11 on both sides, the impact rod 6 resists the radial load, realizing the automatic centering control function of the impact rod 6, and reliably ensuring that the relative movement between the impact rod 6 and the hydrostatic bearing body 1 is non-contact liquid friction.

[0048] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A heavy-duty impact rod static pressure bearing device, characterized in that: The invention comprises a hydrostatic bearing body (1), wherein the hydrostatic bearing body (1) is evenly provided with an even number of pressure oil chambers (11) not less than 4 along the circumferential direction of the inner hole wall, the pressure oil chambers (11) are symmetrically arranged along the axial center of the hydrostatic bearing body (1), a first oil return ring groove (13) is provided at the same interval on both sides of the pressure oil chamber (11) along the axial direction, the inner hole wall of the hydrostatic bearing body (1) between the two first oil return ring grooves (13) and the even number of pressure oil chambers (11) not less than 4, and the pressure oil chambers (11) for impact A damping annular gap (2) is formed between the outer walls of the impact rod (6) and connects the first oil return annular groove (13) and the pressure oil chamber (11); the two first oil return annular grooves (13) are connected to an external oil tank for storing oil through an oil return channel (15); an even number of the pressure oil chambers (11) not less than 4 are respectively connected to a damping structure, and a damping hole (1421) is provided on the damping structure; an even number of the pressure oil chambers (11) not less than 4 are respectively connected to an external pressure oil source through the damping hole (1421).

2. A heavy-duty impact rod static pressure bearing device according to claim 1, characterized in that: The damping structure is an oil inlet passage (14) arranged on the outer wall of the hydrostatic bearing body (1) and connected to the pressure oil chamber (11); a damping plug (142) is installed on the oil inlet passage (14); the damping plug (142) is provided with the damping hole (1421); an end of the oil inlet passage (14) away from the pressure oil chamber (11) is connected to a pressure oil ring groove (12) arranged along the circumferential direction of the outer wall of the hydrostatic bearing body (1); the pressure oil ring groove (12) is connected to a pressure oil passage (51) connected to an external pressure oil source on an impact cylinder (5) for installing the hydrostatic bearing body (1).

3. A heavy-duty impact rod static pressure bearing device according to claim 2, characterized in that: A reduced diameter oil passage (141) is provided at one end of the oil inlet passage (14) close to the pressure oil chamber (11), and a threaded hole (1411) is provided at one end of the reduced diameter oil passage (141) away from the pressure oil chamber (11). The damping plug (142) is sealed and fixedly connected to the threaded hole (1411), and the channel structure and diameter of the damping hole (1421) of each damping plug (142) are the same.

4. A heavy-duty impact rod static pressure bearing device according to claim 3, characterized in that: The oil return channel (15) is a first transverse oil return channel (151) which is transversely connected to the first oil return ring groove (13), and a longitudinal oil return channel (152) which is respectively connected to the two first transverse oil return channels (151) at both ends. A second oil return ring groove (153) is provided on the outer wall of the static pressure bearing body (1). The second oil return ring groove (153) is connected to the longitudinal oil return channel (152) via a second transverse oil return channel (154). The second oil return ring groove (153) is connected to an external oil tank via a transition oil return channel (52) on the impact cylinder body (5).

5. A heavy-duty impact rod static pressure bearing device according to claim 4, characterized in that: The static pressure bearing device also includes a fixed seal assembly (3), the fixed seal assembly (3) includes a first fixed seal (31), a second fixed seal (32) and a third fixed seal (33), a first seal groove (161) and a second seal groove (162) are arranged on both sides of the pressure oil ring groove (12), a third seal groove (163) is arranged on the side of the second seal groove (162) away from the first seal groove (161), the second oil return ring groove (153) is arranged between the second seal groove (162) and the third seal groove (163), and the first fixed seal (31), the second fixed seal (32) and the third fixed seal (33) are installed in the first seal groove (161), the second seal groove (162) and the third seal groove (163) in sequence.

6. A heavy-duty impact rod static pressure bearing device according to claim 5, characterized in that: The hydrostatic bearing device further comprises a sliding seal assembly (4), wherein the sliding seal assembly (4) comprises two sliding seals (41), each of which is provided with a sliding seal groove (17) on the inner hole wall of the first oil return ring groove (13) close to the end of the hydrostatic bearing body (1), and the sliding seals (41) are installed in the sliding seal grooves (17).

7. An impact cylinder, characterized in that: A heavy-duty impact rod hydrostatic bearing device according to any one of claims 1 to 6, comprising an impact cylinder (5), an impact rod (6), and a fixed assembly (7) for fixedly connecting the hydrostatic bearing body (1) and the impact cylinder (5).

8. The impact cylinder according to claim 7, characterized in that: The fixing assembly (7) comprises a cylinder cover (71), wherein the cylinder cover (71) is provided with a through hole through which the impact rod (6) passes, and an end of the cylinder cover (71) close to the impact cylinder body (5) is fixedly connected to the end of the impact cylinder body (5), and the static pressure bearing body (1) is fixedly connected to the cylinder cover (71).

9. The impact cylinder according to claim 8, characterized in that: The fixing assembly (7) further comprises a plurality of latching keys (72); an annular key groove (53) is provided at one end of the impact cylinder body (5) close to the cylinder head (71); a plurality of latching keys (72) are installed in the annular key groove (53); an end of the static pressure bearing body (1) close to the cylinder head (71) is provided with a reduced diameter portion; the reduced diameter portion and the outer wall of the static pressure bearing body (1) form a step (18); an end of the latching key (72) away from the cylinder head (71) abuts against the step (18); a thrust ring (711) is integrally provided on one side of the cylinder head (71) close to the latching key (72); an end of the thrust ring (711) close to the latching key (72) abuts against an end of the latching key (72) close to the cylinder head (71).

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