Hydraulic pilot-operated type adjustable pre-tightening shock absorber

Abstract

The invention relates to the technical field of shock absorbers, in particular to a hydraulic pilot-operated type adjustable pre-tightening shock absorber. The hydraulic pilot-operated type adjustable pre-tightening shock absorber comprises a piston assembly used for providing shock absorption damping and a hydraulic driving assembly, a spring piece is arranged outside the piston assembly, one end of the spring piece is fixed to the piston assembly, the spring piece is used for providing damping force for the piston assembly, and the other end of the spring piece is connected with the hydraulic driving assembly. The hydraulic driving assembly provides axial adjusting force so that the pre-tightening force of the spring piece on the piston assembly can be changed. The hydraulic driving assembly comprises a valve sleeve provided with a pressure control part and an output rotor, the output rotor is installed in the valve sleeve, a gap exists between the output rotor and the upper portion of the valve sleeve, and the output rotor is in sliding fit with the valve sleeve and can rotate and axially move relative to the valve sleeve. The invention provides a shock absorber which is compact in structure, quick in response, easy to realize in engineering and capable of effectively improving the adaptability of a vehicle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shock absorbers, in particular to a hydraulic pilot type adjustable pre-tightening shock absorber. BACKGROUND

[0002] The motorcycle body is compact, light in weight and short in suspension stroke, so it is more easily affected by road unevenness, pothole impact and continuous vibration during driving. The performance of the suspension system is directly related to the comfort, handling and safety of the vehicle.

[0003] At present, the motorcycle suspension system generally adopts the form of spring combined with hydraulic damping elements to realize the functions of damping and supporting. The pre-tightening force of the spring directly determines the static sag of the suspension, the body posture and the adaptability under different loads. Most traditional motorcycles use threaded retaining rings or multi-stage slot structures to adjust the spring pre-tightening force. Although this type of way has simple structure and low manufacturing cost, it has the problems of inconvenient operation, limited adjustment range and inability to realize dynamic adjustment. In the scene where the suspension needs to be optimized frequently according to the road conditions, load or riding mode, these traditional adjustment methods often cannot meet the actual needs.

[0004] In recent years, some high-end models have tried to introduce automatic adjustment mechanisms driven by motors to realize rapid adjustment of the spring pre-tightening force through lead screws or gear mechanisms. However, such mechanical solutions generally have the defects of large size, complex transmission chain, high energy consumption and limited response speed. On the motorcycle platform which is highly sensitive to space, weight and energy efficiency, complex motor-driven solutions not only increase the system cost, but also bring challenges in durability and reliability.

[0005] At the same time, hydraulic drive is concerned in the suspension adjustable technology due to its high power density and fast response speed, but most existing adjustable pre-tightening solutions based on hydraulic valve control still have high system complexity and integration difficulty, and often cannot be applied in the limited installation space of motorcycles.

[0006] In summary, the existing pre-tightening adjustment methods of motorcycle shock absorbers are either too simplified to adapt to complex working conditions or have complex systems and limited integration, and there is still a lack of a shock absorber with compact structure, rapid response and easy engineering implementation. SUMMARY

[0007] The problem solved by the present application is to provide a shock absorber with compact structure, rapid response, easy engineering implementation and effective improvement of vehicle adaptability.

[0008] The hydraulic pilot type adjustable pre-tightening shock absorber comprises a piston assembly for providing damping and a hydraulic drive assembly, the piston assembly is externally provided with a spring member, one end of the spring member is fixed on the piston assembly, the spring member is used for providing damping force for the piston assembly, wherein the other end of the spring member is connected with the hydraulic drive assembly, the hydraulic drive assembly provides an axial adjusting force to change the pre-tightening force of the spring member on the piston assembly; the hydraulic drive assembly comprises a valve sleeve provided with a pressure control part and an output mover, the output mover is installed in the valve sleeve and has a gap containing hydraulic oil on the upper part of the valve sleeve, the output mover is in sliding fit with the valve sleeve and can rotate and axially move relative to the valve sleeve; the output mover is provided with a flow channel, the flow channel is communicated with the gap and the pressure control part; wherein when the output mover rotates, the communication area of the flow channel changes, and then the output mover axially moves to change the axial adjusting force.

[0009] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: by connecting the spring member with the hydraulic drive assembly, the dynamic and rapid adjustment of the pre-tightening force of the spring member is realized by using the hydraulic servo principle, specifically, the output mover in the hydraulic drive assembly can rotate and axially move in the valve sleeve, by changing the communication area of the flow channel, the oil pressure acting on the gap between the valve sleeve and the output mover is adjusted, thereby a variable axial adjusting force is generated. The axial adjusting force directly changes the pre-tightening state of the spring member on the piston assembly, so that the damping characteristics of the shock absorber can be adjusted as required. This design combines the high precision and large thrust of hydraulic servo control with the controllability of screw transmission, realizes linear and continuous adjustment of the pre-tightening force, improves the adaptability of the shock absorber to different working conditions, and by adjusting the pre-tightening force in real time, the shock absorber can provide soft damping when unloaded to improve comfort, and provide sufficient support force when heavily loaded to ensure stability and safety. Secondly, the control mode based on hydraulic servo has fast response speed and high adjustment precision, which is beneficial to realize the collaborative optimization of the shock absorber and the vehicle system and improve the comprehensive performance. Furthermore, the structure integrates the driving and executing mechanisms in the shock absorber, the structure is relatively compact, which helps to save installation space and improve the overall reliability of the system.

[0010] Further, the output mover is a column provided with a spiral groove, the flow channel passes through the spiral groove, the spiral groove is matched with the pressure control part on the valve sleeve, one end face of the column constitutes a pressure bearing surface, and the pressurized oil flowing through the spiral groove acts on the pressure bearing surface to make the column axially move to generate the axial adjusting force; wherein when the column rotates, the communication area of the spiral groove and the pressure control part changes.

[0011] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: by designing the output mover as a column with a spiral groove and matching it with the pressure control part on the valve sleeve, a highly integrated mechanical and hydraulic conversion mechanism is formed. This design utilizes the geometric characteristics of the spiral groove to linearly convert the rotation angle into the flow area, thereby adjusting the oil flow and pressure to the pressure bearing surface. The pressurized oil acts on the pressure bearing surface at the end of the column, directly converting the hydraulic pressure into driving force for the axial movement of the column. This solves the problems of complex structure, large space occupation, long transmission chain and obvious response delay of traditional shock absorbers, enabling effective application in space-limited and fast-response scenarios such as motorcycle shock absorbers.

[0012] Further, the pressure control part includes a hydraulic hole and a hydraulic circuit. The hydraulic hole is provided on the valve sleeve and communicates with the spiral groove. The hydraulic circuit pressurizes or depressurizes the flow passage through the hydraulic hole.

[0013] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: first, due to the high integration and short path of the flow passage, the process from pressurization to action on the pressure bearing surface, or from depressurization to removal of the force, is more rapid, significantly reducing the response time of the system. At the same time, pressure decay and fluctuations caused by long pipelines are avoided, making the axial displacement control of the output mover more accurate, indirectly improving the linearity and accuracy of spring pre-tightening force adjustment. Second, this compact integrated design reduces potential leakage points and cavity volumes in the system, helping to improve the stiffness of the hydraulic system. This enables the system to more effectively suppress pressure fluctuations when responding to rapidly changing loads, ensuring that the shock absorber can provide stable damping force under various working conditions. Third, by coordinating the design of the hydraulic hole and the hydraulic circuit, the key pressure control function is integrated inside the valve sleeve, which is conducive to the miniaturization and modularization of the entire hydraulic drive assembly, making it easier to arrange on platforms such as motorcycles with limited installation space. In addition, the reduction in the number of components and the simplification of the connecting pipelines also reduce the risk of failure caused by loose joints, pipe wall wear, etc., improving the overall reliability of the system.

[0014] Further, the hydraulic circuit includes a hydraulic pump and a two-position two-way electromagnetic valve. The hydraulic pump is used to provide pressurized oil. The outlet of the hydraulic pump is connected to the oil inlet of the two-position two-way electromagnetic valve. The working oil port of the two-position two-way electromagnetic valve is connected to the hydraulic hole. The two-position two-way electromagnetic valve is used to control the on-off state of the hydraulic circuit.

[0015] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: through direct coupling of the hydraulic pump and the two-position two-way electromagnetic valve, efficient and accurate oil path control is achieved. The hydraulic pump continuously provides pressurized oil as a power source, and the outlet thereof is directly connected with the oil inlet of the two-position two-way electromagnetic valve. The electromagnetic valve serves as a core control switch, and the working oil port thereof is directly connected with the hydraulic hole of the actuator. When the electromagnetic valve is powered on, the pressurized oil can pass through to drive the output mover to move axially. When the electromagnetic valve is powered off, the oil path is cut off, and the system can be designed to realize pressure maintaining or unloading.

[0016] Further, the hydraulic drive assembly further comprises a driving unit, which is in transmission connection with the output mover and is used to drive the output mover to rotate.

[0017] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: through introduction of the driving unit and transmission connection of the driving unit with the valve sleeve and the pressure control part of the hydraulic drive assembly, the driving unit and the valve sleeve and the pressure control part of the hydraulic drive assembly can be modularly designed and arranged. The space utilization of the hydraulic drive assembly is improved, and the structure of the entire hydraulic drive assembly is more compact.

[0018] Further, the driving unit comprises a stepping motor and a driving gear driven by the stepping motor; and the end portion of the output mover is fixed with a driven gear which is in meshing connection with the driving gear.

[0019] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: the stepping motor receives pulse signals from the shock absorber control unit, each pulse corresponds to a fixed rotation angle, and high-precision positioning under open-loop control can be achieved without additional feedback sensors. Through transmission of the gear set and possible speed reduction and torque increase, the precise rotation angle of the stepping motor is finally converted into the same precise rotation angle of the output mover, so as to accurately adjust the opening degree of the flow passage and realize stepless or stepwise adjustment of the damping force. Meanwhile, the meshing transmission of the driving gear and the driven gear can arrange the motor laterally, fully utilize the narrow space of the shock absorber laterally, and realize high integration and modularization.

[0020] Further, the hydraulic drive assembly further comprises a connecting piece which fixedly connects the driven gear with the end portion of the output mover, so that the rotation of the driven gear can drive the output mover to rotate synchronously; and an end cover provided with a constraint mechanism which cooperates with the connecting piece to allow the whole composed of the output mover and the driven gear to move axially and restrict the whole from rotating circumferentially.

[0021] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: first, the rigid fixed connection of the output end of the driven gear and the driving end of the output mover by the connecting piece maximally eliminates the backlash in the transmission chain, ensures that each accurate angular displacement instruction of the stepper motor can be transmitted to the output mover without delay and loss; second, the constraint mechanism integrated in the end cover cooperates with the connecting piece, the output mover and the gear integrally slide along the axial direction to adapt to the adjustment stroke of the pre-tightening force, but strictly limits the circumferential rotation of the output mover and the gear, so that the helical groove on the output mover can accurately control the relative position of the hydraulic hole on the valve sleeve, realizes accurate measurement of the hydraulic oil path, ensures the linearity and accuracy of the adjustment, and avoids system out-of-control or efficiency loss caused by accidental rotation of the output mover; third, the guide function is integrated in the end cover, and the additional long guide shaft or complex spline shaft is omitted, so that the structure of the entire hydraulic drive assembly is very compact, and is very suitable for application in motorcycle occasions with limited installation space.

[0022] Further, a linear bushing is arranged between the output mover and the valve sleeve, and the linear bushing provides axial guidance and sealing for the output mover.

[0023] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: in the hydraulic servo system, the output mover needs to perform accurate rotation and axial composite motion in the valve sleeve to realize accurate control of the flow passage. If the output mover directly cooperates with the valve sleeve metal piece, the friction pair will inevitably be worn after long-term operation, resulting in an increase in the cooperation gap between the output mover and the valve sleeve. By arranging the linear bushing between the output mover and the valve sleeve, a low-friction and high-precision guide rail is provided for the axial movement of the output mover, ensuring that the output mover always maintains good straightness during repeated movement, effectively preventing sticking or movement distortion caused by eccentric wear, prolonging the service life of the output mover and the valve sleeve and the like core components, and improving the operation reliability and stability of the shock absorber under long-term and severe working conditions.

[0024] Further, the piston assembly includes a piston cylinder, and the spring piece is sleeved outside the piston cylinder in a concentric gap manner; the lower end of the spring piece is supported by a spring base fixed relative to the piston cylinder; the upper end of the spring piece is limited by a spring snap ring in threaded connection with the piston cylinder; and the spring snap ring and the spring base jointly limit the installation length of the spring piece.

[0025] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: through the cooperative design of the concentric gap sleeving structure, the spring base support and the threaded connection spring snap ring, the stable control of the pre-tightening force of the spring part is realized. Specifically, the spring part is sleeved outside the piston cylinder in a concentric gap manner, ensuring the coincidence degree of the spring axis and the piston cylinder axis, avoiding abnormal wear and stress concentration caused by eccentricity. The spring base is relatively fixed with the piston cylinder, providing a stable lower end support reference for the spring part; and the upper end of the spring snap ring is threaded to the piston cylinder, and the axial position thereof can be accurately adjusted by rotation, so that the distance between the spring snap ring and the spring base, i.e. the installation length pre-compression amount of the spring part, is changed. The spring snap ring and the spring base jointly constitute a pre-tightening force limiting mechanism which can be quantitatively adjusted and mechanically locked.

[0026] Further, the upper end of the piston cylinder is threaded to the lower end of the end cover, the axial adjustment force drives the piston cylinder to move axially, so as to change the axial distance between the spring snap ring and the spring base, realizing the adjustment of the pre-tightening force of the spring part.

[0027] Compared with the prior art, the technical effects achieved by adopting the technical scheme are: by threading the upper end of the piston cylinder to the lower end of the end cover, a rigid and continuous force transmission chain is constructed. The axial adjustment force generated by the hydraulic drive assembly acts on the end cover, and then drives the entire piston cylinder to move axially synchronously through the threaded connection. The axial displacement of the piston cylinder directly changes the axial distance between the spring snap ring and the spring base fixed thereon, so as to accurately and linearly change the installation length of the spring part, i.e. the pre-compression amount of the spring part, and finally realize the stepless adjustment of the pre-tightening force of the spring part. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 A structure schematic view of the hydraulic servo screw type adjustable pre-tightening shock absorber provided by the embodiment of the present application is provided. Figure 2 An explosion schematic view of the hydraulic servo screw type adjustable pre-tightening shock absorber provided by the embodiment of the present application is provided. Figure 3 An assembly schematic view of the hydraulic servo screw type adjustable pre-tightening shock absorber provided by the embodiment of the present application is provided. Figure 4 A structure schematic view of the cylinder provided by the embodiment of the present application is provided. Figure 3 A cross-sectional view of A-A in the embodiment of the present application is provided. Figure 5 A structure schematic view of the cylinder provided by the embodiment of the present application is provided. Figure 6 An explosion schematic view of part of the structure of the hydraulic drive assembly provided by the embodiment of the present application is provided. Figure 7 An assembly schematic view of the output mover is provided. Figure 8The initial position schematic diagram and partial internal structure schematic diagram of the hydraulic servo screw driving principle diagram of the hydraulic servo screw type adjustable pre-tightening shock absorber provided by the embodiment of the present application are provided. Figure 9 For Figure 8 The middle column body rotates clockwise along the positive direction of the Y axis, and the partial internal structure schematic diagram is shown. Figure 10 For Figure 8 The middle column body moves along the negative direction of the Y axis, and the partial internal structure schematic diagram is shown.

[0029] Explanation of reference signs: 100-piston assembly; 200-spring part; 300-hydraulic drive assembly; 2-motor support; 3-valve sleeve; 4-stepping motor; 5-left gear housing; 6-linear bushing; 7-piston cylinder; 8-spring snap ring; 10-damping piston; 11-bottom sealing part; 12-piston rod; 13-spring base; 14-right gear housing; 15-column body; 16-connection part; 17-driven gear; 18-end cover; 22-restraint mechanism; 32-clearance; 33-output mover; 34-spiral groove; 35-pressure bearing surface; 36-hydraulic hole; 38-hydraulic pump; 39-two-position two-way electromagnetic valve; 40-driving unit; 41-liquid flow channel; 42-driving gear. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0031] The embodiment provides a hydraulic pilot type adjustable pre-tightening shock absorber, which is one of important parts of a motorcycle, and functions to absorb and dissipate vibration energy of the motorcycle generated due to uneven road surface by using damping force generated by the shock absorber, thereby ensuring ride comfort, control stability and driving safety of the vehicle.

[0032] The pre-tightening force adjustment mode of the existing motorcycle shock absorber is either too simple to adapt to complex working conditions, or the system is complex and integration is limited, and there is still a lack of a shock absorber with compact structure, rapid response and easy engineering implementation.

[0033] In view of the above problems, referring to Figures 1-7The hydraulic pilot type adjustable pre-tightening shock absorber comprises a piston assembly 100 for providing damping resistance and a hydraulic drive assembly 300, the piston assembly 100 is externally provided with a spring member 200, one end of the spring member 200 is fixed on the piston assembly 100, and the spring member 200 is used for providing damping force to the piston assembly 100, wherein the other end of the spring member 200 is connected with the hydraulic drive assembly 300, and the hydraulic drive assembly 300 provides an axial adjusting force to change the pre-tightening force of the spring member 200 on the piston assembly 100; the hydraulic drive assembly 300 comprises a valve sleeve 3 provided with a pressure control part and an output mover 33, the output mover 33 is installed in the valve sleeve 3 and is in sliding fit with the valve sleeve 3, and can rotate and axially move relative to the valve sleeve 3; the output mover 33 is provided with a liquid flow channel 41, and the liquid flow channel 41 is communicated with the gap 32 and the pressure control part; when the output mover 33 rotates, the communication area of the liquid flow channel 41 changes, and then the output mover 33 axially moves to change the axial adjusting force.

[0034] By connecting the spring member 200 with the hydraulic drive assembly 300, the dynamic and rapid adjustment of the pre-tightening force of the spring member 200 is realized by using the hydraulic servo principle, specifically, the output mover 33 in the hydraulic drive assembly 300 can rotate and axially move in the valve sleeve 3, the oil pressure in the gap 32 between the valve sleeve 3 and the output mover 33 is adjusted by changing the communication area of the liquid flow channel 41, so that a variable axial adjusting force is generated. The axial adjusting force directly changes the pre-tightening state of the spring member 200 on the piston assembly 100, so that the damping characteristics of the shock absorber can be adjusted as needed. This design combines the high precision and large thrust of hydraulic servo control with the controllability of screw transmission, realizes linear and continuous adjustment of the pre-tightening force, improves the adaptability of the shock absorber to different working conditions, and by adjusting the pre-tightening force in real time, the shock absorber can provide soft damping when unloaded to improve comfort, and provide sufficient support force when heavy loaded to ensure stability and safety. Secondly, the control mode based on hydraulic servo has fast response speed and high adjustment precision, which is beneficial to realize the collaborative optimization of the shock absorber and the vehicle system and improve the comprehensive performance. Furthermore, the structure integrates the driving and executing mechanism in the shock absorber, which is relatively compact, helps to save installation space and improve the overall reliability of the system.

[0035] The working principle of the hydraulic pilot type adjustable pre-tightening shock absorber is described below, and the working process can be divided into the following three stages, as shown in Figures 8-10In the initial static state, the hydraulic circuit is supplied by the hydraulic pump 38, the oil enters the gap 32 through the hydraulic hole 36 of the valve sleeve 3, the oil pressure acts on the pressure surface 35 of the cylinder 15, generating an axial thrust in the negative direction of the Y axis, at the same time, the spring member 200 has an initial pre-tightening force, which is fed back through the piston cylinder 7 and the end cover 18, generating a reverse upward force, which balances the axial thrust generated by the oil pressure, the system maintains a static force balance state, the position of the cylinder 15 remains stable, the two-position two-way electromagnetic valve 39 is in the closed state, and the system maintains pressure sealing. Referring to the figure, when the spring pre-tightening force needs to be increased, the stepper motor 4 drives the driven gear 17 through the driving gear 42, drives the cylinder 15 to rotate, the helical groove 34 of the output mover 33 forms a variable opening with the valve sleeve 3, increases the oil passage flow, the pressure in the gap 32 rises, breaks the original balance, and pushes the cylinder 15 to move along the negative direction of the Y axis. This increased downward thrust pushes the output mover 33 and moves the piston cylinder 7 downward through the end cover 18. The downward movement of the piston cylinder 7 compresses the spring member 200 outside, thereby increasing the pre-tightening force of the spring member 200. The system will automatically reach a new force balance position, at which time the spring member 200 is compressed to a new length, the pre-tightening force is increased to adapt to the new load or working condition, and the rotation angle of the cylinder 15 determines the size of the final pre-tightening force. When the pre-tightening force needs to be reduced or the system needs to be reset, the two-position two-way electromagnetic valve 39 in the hydraulic circuit is energized to switch to the pressure relief state. The oil pressure in the entire system is quickly released, and the downward hydraulic thrust acting on the cylinder 15 disappears or decreases sharply. At this time, the elastic restoring force of the compressed spring member 200 is much greater than the remaining hydraulic pressure, and this restoring force will push the piston cylinder 7 and the output mover 33 to move upward to return to position, thereby reducing the spring pre-tightening force until it returns to or approaches the initial state.

[0036] Specifically, referring to Figures 2-5 , the output mover 33 is a cylinder 15 provided with a helical groove 34, a liquid flow channel 41 passes through the helical groove 34, the helical groove 34 cooperates with the pressure control part on the valve sleeve 3, and one end surface of the cylinder 15 constitutes a pressure surface 35. The pressurized oil flowing through the helical groove 34 acts on the pressure surface 35 to make the cylinder 15 move axially to generate an axial adjusting force; wherein the communication area of the helical groove 34 and the pressure control part changes when the cylinder 15 rotates.

[0037] For example, the cylinder 15 can be provided in a cylindrical shape, and the helical groove 34 can be provided in a single helical inclined groove, a double helical inclined groove, or a symmetrical helical inclined groove. The inclined groove can be regarded as a helical guide rail penetrating through the cylinder 15. When high-pressure oil flows from the pressure control part, the oil will enter the inclined groove. At this time, if the cylinder 15 is forcibly rotated, the groove wall of the inclined groove will interact with the high-pressure oil, or in other words, the oil pressure will generate a component force along the inclined surface of the inclined groove, pushing the cylinder 15 to move linearly along its axial direction.

[0038] By designing the output mover 33 as a cylinder 15 with helical grooves 34 and matching it with the pressure control part on the valve sleeve 3, a highly integrated mechanical and hydraulic conversion mechanism is formed. This design utilizes the geometric properties of the helical grooves 34 to linearly convert the rotation angle into flow area, thereby adjusting the flow rate and pressure of the oil flowing to the pressure bearing surface 35. The pressurized oil acts on the pressure bearing surface 35 at the end of the cylinder 15, directly converting hydraulic pressure into driving force for the axial movement of the cylinder 15. This solves the problems of complex structure, large space occupation, long transmission chain, and obvious response delay in traditional shock absorbers, enabling effective application in space-limited and fast-response scenarios such as motorcycle shock absorbers. Further, the helical pair has good self-locking characteristics, combined with the mechanical feedback of the spring member 200, to achieve stable automatic return during hydraulic unloading, ensuring sensitive, stable, and safe adjustment process, and avoiding pre-tightening force drift caused by external disturbances or system leakage.

[0039] Specifically, referring to Figures 1-5 , the pressure control part includes a hydraulic hole 36 and a hydraulic circuit. The hydraulic hole 36 is provided on the valve sleeve 3, and the hydraulic hole 36 communicates with the helical groove 34. The hydraulic circuit pressurizes or depressurizes the flow passage 41 through the hydraulic hole 36.

[0040] For example, the hydraulic hole 36 can be provided with multiple corresponding to the number of helical grooves 34.

[0041] Firstly, due to the high integration and extremely short path of the flow passage 41, the process of pressurizing the hydraulic oil to act on the pressure bearing surface 35 or depressurizing to remove the force is more rapid, significantly reducing the response time of the system. At the same time, it avoids the pressure decay and fluctuation caused by long pipelines, making the axial displacement control of the output mover 33 more accurate, and indirectly improving the linearity and accuracy of the spring pre-tightening force adjustment. Secondly, this compact integrated design reduces the potential leakage points and cavity volume in the system, which helps to improve the stiffness of the hydraulic system. This makes the system more effectively suppress pressure fluctuations when dealing with rapidly changing loads, ensuring that the shock absorber can provide stable damping force under various working conditions. Thirdly, by the cooperative design of the hydraulic hole 36 and the hydraulic circuit, the key pressure control function is integrated inside the valve sleeve 3, which is beneficial to the miniaturization and modularization of the entire hydraulic drive assembly 300, making it easier to arrange on platforms such as motorcycles with limited installation space. In addition, the reduction in the number of components and the simplification of the connecting pipelines also reduce the risk of failure caused by loose joints, pipe wall wear, etc., improving the overall reliability of the system.

[0042] Specifically, referring to Figure 2The hydraulic circuit comprises a hydraulic pump 38 and a two-position two-way electromagnetic valve 39. The hydraulic pump 38 is used to provide pressurized oil, and the outlet of the hydraulic pump 38 is connected to the oil inlet of the two-position two-way electromagnetic valve 39. The working oil port of the two-position two-way electromagnetic valve 39 is connected to the hydraulic hole 36. The two-position two-way electromagnetic valve 39 is used to control the on-off state of the hydraulic circuit.

[0043] The direct coupling of the hydraulic pump 38 and the two-position two-way electromagnetic valve 39 realizes efficient and accurate oil circuit control. The hydraulic pump 38 continuously provides pressurized oil, and its outlet is directly connected to the oil inlet of the two-position two-way electromagnetic valve 39. The electromagnetic valve serves as the core control switch, and its working oil port is directly connected to the hydraulic hole 36 of the actuator. When the electromagnetic valve is powered on, pressurized oil can pass through to drive the output rotor 33 to move axially. When the electromagnetic valve is powered off, the oil circuit is cut off, and the system can be designed to maintain pressure or unload.

[0044] Specifically, referring to Figure 1 and Figure 5 , the hydraulic drive assembly 300 further comprises a drive unit 40, which is in transmission connection with the output rotor 33 and is used to drive the output rotor 33 to rotate.

[0045] By introducing the drive unit 40 and connecting it in transmission with the output rotor 33, the drive unit 40 and the valve sleeve 3 and the pressure control part of the hydraulic drive assembly 300 can be designed and arranged in a modular manner. This improves the space utilization of the hydraulic drive assembly 300 and makes the entire hydraulic drive assembly 300 more compact.

[0046] Specifically, referring to Figures 1-5 , the drive unit 40 comprises a stepper motor 4 and a driving gear 42 driven by the stepper motor 4. The end of the output rotor 33 is fixed with a driven gear 17, and the driven gear 17 is in engagement with the driving gear 42.

[0047] For example, the driven gear 17 is a sector gear, which is in engagement with the driving gear 42 of the stepper motor 4. The stepper motor 4 drives the sector gear to rotate, and at the same time, the rotation is decelerated and the torque is amplified.

[0048] The stepper motor 4 receives pulse signals from the shock absorber control unit, and each pulse corresponds to a fixed rotation angle. Without additional feedback sensors, high-precision positioning can be achieved under open-loop control. Through the transmission of the gear set and possible deceleration and torque amplification, the precise rotation angle of the stepper motor 4 is converted into the same precise rotation angle of the output rotor 33, so as to accurately adjust the opening of the flow passage 41 and realize stepless or stepwise adjustment of the damping force. At the same time, the engagement transmission between the driving gear 42 and the driven gear 17 can arrange the motor laterally, fully utilize the narrow space on the side of the shock absorber, and realize high integration and modularity.

[0049] In particular, referring to Figures 1-5 The hydraulic drive assembly 300 further comprises a connecting member 16 rigidly connecting the output end of the driven gear 17 with the driving end of the output mover 33, and an end cover 18 provided with a constraint mechanism 22, which cooperates with the connecting member 16 to allow the output mover 33 and the driven gear 17 to move axially as a whole and restrict the rotation of the whole.

[0050] For example, the connecting member 16 can be a mushroom screw, and the constraint mechanism can be a clamping groove on the end cover 18. The limit angle of rotation of the sector gear is limited by the clamping groove. The column 15 is fixed with the sector gear by the mushroom head screw, and the sector gear drives the column 15 to rotate in the clamping groove. At the same time, the mushroom screw of the connecting member 16 can be embedded in the clamping groove on the end cover 18, so that the two are fixed like a groove, and the follow-up push-pull effect can be achieved.

[0051] For example, the valve sleeve 3 is fixed to the end cover 18 through the motor bracket 2 and the left gear housing 5 and the right gear housing 14, further integrating the structure.

[0052] Firstly, the connecting member 16 rigidly connects the output end of the driven gear 17 with the driving end of the output mover 33, which maximally eliminates the backlash in the transmission chain, ensuring that each precise angular displacement command of the stepper motor 4 can be transmitted to the output mover 33 without delay and loss. Secondly, the constraint mechanism 22 integrated in the end cover 18 cooperates with the connecting member 16, allowing the output mover 33 and the gear to move axially as a whole, and strictly limiting the rotation of the whole, so that the helical groove 34 on the output mover 33 can accurately control the relative position of the hydraulic hole 36 on the valve sleeve 3, realizing accurate measurement of the hydraulic oil circuit, ensuring the linearity and accuracy of the adjustment, and avoiding system out-of-control or efficiency loss caused by accidental rotation of the output mover 33. Thirdly, the guide function is integrated in the end cover 18, eliminating the need for an extra long guide shaft or a complex spline shaft, making the entire hydraulic drive assembly 300 very compact and very suitable for application in motorcycle situations where installation space is limited.

[0053] In particular, referring to Figures 1-5 A linear bushing 6 is provided between the output mover 33 and the valve sleeve 3, which provides axial guidance and sealing for the output mover 33.

[0054] For example, the bushing is made of a material with certain elasticity or self-lubricating properties, such as polytetrafluoroethylene, graphite, nylon or bronze, etc. When it is pressed into the inner wall of the valve sleeve 3 with interference fit, and forms a tight gap 32 with the output mover 33, it can effectively block the leakage of high-pressure oil along the fitting gap 32.

[0055] In the hydraulic servo system, the output mover 33 needs to perform accurate rotation and axial compound motion in the valve sleeve 3 to achieve precise control of the flow passage 41. If the output mover 33 directly cooperates with the valve sleeve 3 metal piece, the friction pair will inevitably wear after long-term operation, resulting in an increase in the cooperation gap 32. By setting the linear bushing 6 between the output mover 33 and the valve sleeve 3, a low-friction and high-precision guide rail can be provided for the axial movement of the output mover 33, ensuring that the output mover 33 always maintains good straightness during repeated motion, effectively preventing sticking or motion distortion due to eccentric wear, prolonging the service life of the output mover 33 and the valve sleeve 3 and other core components, and improving the operation reliability and stability of the shock absorber under long-term and harsh conditions.

[0056] Specifically, referring to Figures 1-5 , the piston assembly 100 includes a piston cylinder 7, and a spring member 200 is sleeved outside the piston cylinder 7 in a concentric gap 32 manner; the lower end of the spring member 200 is supported by a spring base 13 fixed relative to the piston cylinder 7; the upper end of the spring member 200 is limited by a spring snap ring 8 threadedly connected with the piston cylinder 7; the spring snap ring 8 and the spring base 13 jointly define the installation length of the spring member 200.

[0057] Through the cooperative design of the concentric gap 32 sleeving structure, the spring base 13 support, and the threaded connection spring snap ring 8, stable control of the pre-tightening force of the spring member 200 is achieved.

[0058] For example, the piston assembly 100 further includes a damping piston 10, a piston rod 12, and a bottom sealing member 11, the bottom sealing member 11 is in interference fit with the bottom end of the piston cylinder 7 to form a sealed cavity in the piston cylinder 7; the damping piston 10 is arranged in the sealed cavity and is in sliding fit with the piston cylinder 7, and is used for axial movement in the cavity to provide damping. One end of the piston rod 12 is threadedly connected with the damping piston 10, and both of them move together; the other end of the piston rod 12 extends out of the bottom sealing member 11 for external connection. When external vibration is transmitted through the piston rod 12 to drive the damping piston 10 to reciprocate in the sealed piston cylinder 7 filled with hydraulic oil, a large fluid resistance is generated by the oil passing through the throttle hole on the damping piston 10, thereby consuming energy and achieving the purpose of damping vibration.

[0059] Specifically, the spring member 200 is sleeved on the outside of the piston barrel 7 in a concentric gap 32 manner, ensuring the coincidence of the spring axis and the piston barrel 7 axis, avoiding abnormal wear and stress concentration caused by eccentricity. The spring base 13 is fixed relative to the piston barrel 7, providing a stable lower end support reference for the spring member 200; and the upper end is connected to the spring retainer 8 of the piston barrel 7 through threads, and the axial position thereof can be accurately adjusted by rotation, thereby changing the distance between the spring retainer 8 and the spring base 13, i.e. the installation length pre-compression amount of the spring member 200. The spring retainer 8 and the spring base 13 jointly constitute a pre-tightening force limiting mechanism that can be quantitatively adjusted and mechanically locked.

[0060] Specifically, referring to Figures 1-5 , the upper end of the piston barrel 7 is threadedly connected to the lower end of the end cover 18, the axial adjustment force drives the piston barrel 7 to move axially, thereby changing the axial distance between the spring retainer 8 and the spring base 13, and realizing the adjustment of the pre-tightening force of the spring member 200.

[0061] By threadedly connecting the upper end of the piston barrel 7 to the lower end of the end cover 18, a rigid and continuous force transmission chain is constructed. The axial adjustment force generated by the hydraulic drive assembly 300 acts on the end cover 18, and then drives the entire piston barrel 7 to move axially synchronously through the threaded connection. The axial displacement of the piston barrel 7 directly changes the axial distance between the spring retainer 8 and the spring base 13 fixed thereon, thereby accurately and linearly changing the installation length of the spring member 200, i.e. the pre-compression amount of the spring member 200, and finally realizing the stepless adjustment of the pre-tightening force of the spring member 200.

[0062] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art, without departing from the spirit and scope of the present application, can make various changes and modifications, therefore the protection scope of the present application should be subject to the range defined by the claims.

Claims

1. A hydraulic pilot operated adjustable pre-load damper, characterized by, The hydraulic pilot type adjustable pre-tightening shock absorber comprises: A piston assembly for providing damping resistance, the piston assembly is externally provided with a spring member, one end of the spring member is fixed on the piston assembly, the spring member is used for providing damping force to the piston assembly, wherein the other end of the spring member is connected with a hydraulic drive assembly, the hydraulic drive assembly provides an axial adjustment force to change the pre-tightening force of the spring member on the piston assembly; The hydraulic drive assembly comprises a valve sleeve provided with a pressure control part and an output mover, the output mover is installed in the valve sleeve, the upper end of the output mover and the upper part of the valve sleeve have a gap for containing hydraulic oil, the output mover is in sliding fit with the valve sleeve and can rotate and move axially relative to the valve sleeve, the output mover is provided with a flow channel, the flow channel communicates the gap and the pressure control part; Wherein, when the output mover rotates, the communication area of the flow channel changes, and then the output mover moves axially to change the axial adjustment force.

2. The hydraulic pilot-operated adjustable pre-load damper of claim 1, wherein, The output mover is a column provided with a spiral groove, the flow channel passes through the spiral groove, the spiral groove cooperates with the pressure control part, one end surface of the column forms a pressure bearing surface, and the pressurized oil flowing through the spiral groove acts on the pressure bearing surface to make the column move axially to generate the axial adjustment force; Wherein, when the column rotates, the communication area of the spiral groove and the pressure control part changes.

3. The hydraulic pilot-operated adjustable pre-load damper of claim 2, wherein, The pressure control part comprises a hydraulic hole and a hydraulic circuit, the hydraulic hole is arranged on the valve sleeve, the hydraulic hole communicates with the spiral groove, and the hydraulic circuit pressurizes or depressurizes the flow channel through the hydraulic hole.

4. The hydraulic pilot-operated adjustable pre-load damper of claim 3, wherein, The hydraulic circuit comprises a hydraulic pump and a two-position two-way electromagnetic valve, the hydraulic pump is used for providing the pressurized oil, the outlet of the hydraulic pump is connected with the oil inlet of the two-position two-way electromagnetic valve, the working oil port of the two-position two-way electromagnetic valve is connected with the hydraulic hole, and the two-position two-way electromagnetic valve is used for controlling the on-off state of the hydraulic circuit.

5. The hydraulic pilot-operated adjustable pre-load damper according to any one of claims 1-4, characterized in that, The hydraulic drive assembly further comprises a drive unit, the drive unit is in transmission connection with the output mover and is used for driving the output mover to rotate.

6. The hydraulic pilot-operated adjustable pre-load damper of claim 5, wherein, The drive unit comprises a stepping motor and a driving gear driven by the stepping motor, and the end of the output mover is fixed with a driven gear which is in mesh with the driving gear.

7. The hydraulic pilot-operated adjustable pre-load damper of claim 6, wherein, The hydraulic drive assembly further comprises: A connecting piece, the connecting piece fixedly connects the driven gear with the end of the output mover, so that the rotation of the driven gear can drive the output mover to rotate synchronously; An end cover provided with a constraint mechanism, the constraint mechanism cooperates with the connecting piece to allow the whole composed of the output mover and the driven gear to move axially and restrict the whole to rotate circumferentially.

8. The hydraulic pilot-operated adjustable pre-load damper of claim 7, wherein, A linear bushing is arranged between the output mover and the valve sleeve, the linear bushing provides axial guidance and sealing for the output mover.

9. The hydraulic pilot-operated adjustable pre-load damper of claim 8, wherein, The piston assembly comprises a piston cylinder, and the spring member is arranged outside the piston cylinder in a concentric gap manner. The lower end of the spring member is supported by a spring base fixed relative to the piston cylinder; the upper end of the spring member is limited by a spring retainer threadedly connected to the piston cylinder; the spring retainer and the spring base jointly define the installation length of the spring member.

10. The hydraulic pilot-operated adjustable pre-load damper of claim 9, wherein, The upper end of the piston cylinder is threadedly connected to the lower end of the end cover, the axial adjustment force pushes the piston cylinder to move axially, thereby changing the axial distance between the spring retainer and the spring base, and realizing the adjustment of the pre-tightening force of the spring member.

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