Hydraulic shock absorber and air spring shock absorber assembly structure

Abstract

The invention belongs to the technical field of automobile suspensions, and particularly relates to a hydraulic shock absorber and an air spring shock absorber assembly structure. According to the hydraulic shock absorber, a buffer column is arranged at the bottom of a lower cavity, and a buffer sleeve synchronously and axially reciprocates along with a piston is arranged on the piston, so that the buffer column enters and exits from an inner cavity of the buffer sleeve; when the buffer column blocks the lower end opening of the buffer sleeve, an annular cavity is defined by the outer wall of the buffer sleeve, the side wall of the buffer column and the side wall of the lower cavity, oil in the annular cavity enters the upper cavity through the throttling pipeline and the first throttling channel, the throttling pipeline limits the flow of the oil entering the upper cavity, the downward pressing damping force of a piston is increased, and the damping performance of the damper is improved. And when the buffer column shields the inner port of the throttling pipeline, the flow of the throttling pipeline is limited, the downward pressing damping force of the piston is increased again, and the damping performance of the damper is further improved. The air spring shock absorber assembly structure adopts the shock absorber, the structure is simple, the space of an air chamber of the air spring and the installation space needed by the air spring are reduced, and installation is convenient.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile suspension systems, and in particular relates to a hydraulic shock absorber and an air spring shock absorber assembly structure. Background Art

[0002] The air spring shock absorber assembly structure is an important component of the automobile suspension system, which has an important impact on the stability and safety of vehicle driving. The air spring shock absorber assembly structure includes an air spring and a shock absorber that are used in conjunction with each other. The air spring includes a top seat assembly, an air bag and a piston cylinder arranged from top to bottom. The top seat assembly is sealed with the upper end of the air bag, and the air spring piston cylinder is sealed with the lower end of the air bag to form an air chamber for containing compressed air. The shock absorber includes a cylinder body and a piston rod. The cylinder body includes an outer cylinder and an inner cylinder located in the outer cylinder. A piston is provided at the lower end of the piston rod. The lower end of the piston rod and the piston are both located in the cavity of the inner cylinder. The piston fits tightly with the side wall of the inner cylinder to separate the inner cylinder into an upper chamber and a lower chamber. A throttling channel connecting the upper chamber and the lower chamber is provided on the piston. The outer cylinder of the shock absorber is arranged in the piston cylinder of the air spring and the two are sealed connected. The upper end of the piston rod of the shock absorber passes through the air chamber and the top seat assembly of the air spring and is sealed connected to the top seat assembly. When the top seat assembly of the air spring drives the piston rod and the piston to reciprocate axially, the hydraulic oil in the inner cylinder of the shock absorber flows repeatedly between the upper chamber and the lower chamber through the throttling channel on the piston rod to generate a damping force, thereby realizing hydraulic buffering of the piston movement of the shock absorber.

[0003] Although the above-mentioned air spring and strut assembly structure can meet the shock absorption requirements of automobiles in most cases, when the vehicle is bumping up and down on a rough and bad road or when emergency braking is performed during driving, the vehicle body will move violently in the up and down directions relative to the wheels. At the same time, the vehicle body drives the piston rod and the piston to move synchronously up and down. At this time, the damping force generated by the throttling channel on the piston in the existing shock absorber to limit the flow of oil is insufficient, which can easily cause the shock absorber piston to bottom out, that is, the shock absorber piston and the bottom surface of the cylinder inner tube rigidly collide and cause the shock absorber to be damaged. In order to prevent the piston from bottoming out, the existing structure sets an elastic buffer block in the air chamber of the air spring. The elastic buffer block is generally installed on the piston rod between the shock absorber cylinder and the air spring top seat assembly. When the top seat assembly and the piston rod are pressed down too much, the buffer block is driven to drop synchronously until the buffer block is squeezed up and down by the top seat assembly and the shock absorber cylinder to elastically deform to achieve the movement buffer of the piston rod. At the same time, the elastic buffer block separates the top seat assembly and the shock absorber cylinder by a certain safety distance to prevent the shock absorber from bottoming out. However, the structure still has the following shortcomings:

[0004] 1. The elastic buffer block is easily damaged after multiple impacts and needs to be replaced in time, which increases maintenance costs;

[0005] 2. The elastic buffer block occupies the air chamber space of the air spring, which may lead to insufficient air storage space in the air chamber, affecting the performance of the air spring. In order to meet the performance of the air spring, it is often necessary to increase the air chamber space of the air spring and redesign the structure of the air spring. The air spring after the structural design change requires a larger installation space. For this reason, it is even necessary to replan the entire chassis space layout, which brings difficulties and inconveniences to the structural design of the chassis, increases the workload of designers and production personnel, and reduces production efficiency;

[0006] 3. Some vehicles require that the axis of the air spring top seat assembly intersect with the axis of the shock absorber piston rod, such as the McPherson air spring shock absorber assembly structure. When the angle between the piston rod axis and the axis of the air spring top seat is large, the elastic buffer block is likely to interfere with the piston rod, affecting the shock absorbing performance of the overall structure, accelerating the wear of the piston rod and the elastic buffer block, and shortening the life of the air spring shock absorber assembly structure. Summary of the invention

[0007] The technical problems to be solved by the present invention are: to provide a hydraulic shock absorber, which increases the damping force of the downward movement of the piston and the piston rod after the downward movement amplitude of the piston rod exceeds a specified amplitude, provides a buffer for the downward movement of the piston rod, avoids the rigid collision between the piston and the inner tube of the shock absorber, and improves the reliability of the shock absorber; and to provide an air spring shock absorber assembly structure, simplifies the connection structure between the shock absorber and the air spring top seat, saves the air chamber space of the air spring, reduces the total volume of the air spring and the required installation space, and facilitates assembly.

[0008] The technical solution adopted by the present invention to solve the technical problem is: a hydraulic shock absorber, comprising an outer cylinder, an inner cylinder and a piston rod arranged from outside to inside, a compensation chamber is provided between the outer cylinder and the inner cylinder; the lower end of the piston rod is located in the inner cylinder and a piston is provided at the lower end of the piston rod, the piston divides the inner chamber of the inner cylinder into an upper chamber and a lower chamber; the piston is provided with a first throttling channel and a second throttling channel connecting the upper chamber and the lower chamber, the first throttling channel is provided with a first one-way valve leading to the upper chamber, and the second throttling channel is provided with a second one-way valve leading to the lower chamber; the bottom wall of the inner cylinder is provided with a third throttling channel and a fourth throttling channel connecting the lower chamber and the compensation chamber, the third throttling channel is provided with a third one-way valve leading to the compensation chamber, and the fourth throttling channel is provided with a fourth one-way valve leading to the lower chamber;

[0009] The lower chamber is provided with a buffer sleeve and a buffer column coaxially arranged up and down, the buffer sleeve is connected to the piston, and the lower ports of the first throttling channel and the second throttling channel are both located in the cavity of the buffer sleeve; the buffer column is fixedly arranged at the bottom of the lower chamber; the wall of the buffer sleeve is provided with a throttling pipeline that passes through inside and outside;

[0010] The piston is used to drive the buffer sleeve to axially reciprocate up and down so that the upper end of the buffer column moves in and out of the buffer sleeve; when the buffer sleeve moves to the lower limit position, the buffer column is located in the buffer sleeve cavity and is gap-matched with it, and the side wall of the buffer column blocks all inner ports of the throttling pipeline.

[0011] Furthermore, a limit slot perpendicular to the axis of the piston is provided at the lower portion of the outer side surface of the piston, and a clamping block having a shape and size matching the limit slot is provided on the buffer sleeve, and the clamping block is located in the limit slot and axially clamped with the side wall of the slot;

[0012] The buffer sleeve is provided with a guide portion protruding from the outer side wall thereof, and the guide portion is axially slidably matched with the inner tube; and the guide portion is provided with an axially penetrating oil passage.

[0013] Furthermore, a transition slope is provided between the bottom wall of the buffer sleeve and the inner side wall of the buffer sleeve, and is arranged downwardly and obliquely from the inside to the outside.

[0014] Furthermore, the buffer column is a cylindrical structure with openings at both ends.

[0015] Furthermore, a lower mounting seat is provided on the bottom wall of the lower chamber, and the lower mounting seat is interference fit with the inner tube; an axial step through hole is provided on the lower mounting seat, and the lower end of the buffer column is inserted into the axial step through hole and interference fit therewith, and the lower end surface of the buffer column is axially abutted against the step in the axial step through hole.

[0016] Furthermore, the top surface of the lower mounting seat is provided with an elastic member which is arranged vertically aligned with the buffer sleeve.

[0017] Furthermore, there are multiple throttling pipelines, and the multiple throttling pipelines are evenly arranged along the circumference of the buffer sleeve; the axial positions of the inner ports of the multiple throttling pipelines are different.

[0018] Furthermore, the throttling pipeline is a plurality of strip grooves arranged on the inner wall of the buffer sleeve, the length direction of the strip grooves is arranged along the axial direction of the buffer sleeve, the lower ends of the strip grooves are open and the lower end openings are located on the bottom wall of the buffer sleeve;

[0019] The throttling pipelines of the multiple strip-shaped groove structures have different lengths.

[0020] Furthermore, the groove depth and groove width of the throttling pipeline of the strip groove structure gradually decrease from bottom to top.

[0021] An air spring shock absorber assembly structure includes an air spring, wherein the air spring includes a top seat assembly, a bladder skin and a piston cylinder arranged from top to bottom, one end of the bladder skin is sealed and connected to the top seat assembly, and the other end of the bladder skin is sealed and connected to the piston cylinder, and the top seat assembly, the bladder skin and the piston cylinder form an air chamber;

[0022] Also includes any of the above hydraulic shock absorbers;

[0023] The outer cylinder of the shock absorber is installed in the piston cylinder of the air spring and the two are sealed and connected. The upper end of the shock absorber piston rod passes through the air chamber of the air spring and is sealed and connected to the top seat assembly of the air spring.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: a hydraulic shock absorber is provided, wherein a buffer column is arranged at the bottom of the lower chamber, and a buffer sleeve is arranged on the piston for synchronous axial reciprocating movement with the piston so that the upper end of the buffer column can axially enter and exit the inner cavity of the buffer sleeve; when the piston drives the buffer sleeve to move downward with an excessive amplitude, the buffer column enters the buffer sleeve to block the lower port of the buffer sleeve, and the outer wall of the buffer sleeve, the side wall of the buffer column located outside the buffer sleeve and the side wall of the lower chamber form an annular cavity, and the oil in the annular cavity mainly enters the cavity of the buffer sleeve through the throttling pipeline, and the oil in the cavity of the buffer sleeve then enters the upper chamber through the first throttling channel, and the throttling pipeline has a great influence on the oil entering The oil flow in the inner cavity of the buffer sleeve is limited, which indirectly limits the flow of oil entering the first throttling channel, slows down the speed of oil entering the upper chamber from the lower chamber, increases the damping force of the downward movement of the piston, and improves the vibration reduction performance of the shock absorber; when the piston drives the buffer sleeve to continue to move downward so that the buffer column blocks the port in the throttling pipeline, the buffer column limits the flow of the throttling pipeline, further limits the flow of oil entering the first throttling channel, slows down the speed of oil entering the upper chamber from the lower chamber, and again increases the damping force of the downward movement of the piston and piston rod, further improves the vibration reduction performance of the shock absorber, avoids insufficient support force of the air spring causing rigid collision between the piston and the bottom wall of the buffer sleeve, and improves vehicle driving comfort.

[0025] An air spring shock absorber assembly structure is provided. By adopting the shock absorber, the piston rod is prevented from driving the piston to move downward and rigidly colliding with the bottom wall of the shock absorber inner tube, and an elastic buffer block does not need to be arranged in the air chamber of the air spring, so as to avoid mutual interference between the elastic buffer block and the piston rod, simplify the connection structure between the top seat assembly of the air spring and the shock absorber piston rod, save the air chamber space of the air spring, reduce the total volume of the air spring, reduce the installation space required for the air spring, and facilitate the layout and installation of the overall structure of the vehicle suspension. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of the axial cross-sectional structure of the hydraulic shock absorber of the present invention;

[0027] Figure 2 It is a schematic diagram of the axial cross-sectional structure of the hydraulic shock absorber when the buffer column just begins to enter the buffer sleeve;

[0028] Figure 3 It is a schematic diagram of the axial cross-sectional structure when the buffer sleeve of the hydraulic shock absorber moves to the lower limit position;

[0029] Figure 4 It is a schematic diagram of the structure of the air spring shock absorber assembly of the present invention;

[0030] Figure 5 yes Figure 3 A schematic diagram of the enlarged structure of the middle part A;

[0031] Figure 6 yes Figure 4 A schematic diagram of the enlarged structure of the middle B part;

[0032] Figure markings: 1-outer cylinder; 11-compensating chamber; 12-sealing end cover; 2-inner cylinder; 21-upper chamber; 211-annular chamber; 22-lower chamber; 23-third throttling channel; 24-fourth throttling channel; 25-third one-way valve; 26-fourth one-way valve; 3-piston rod; 4-piston; 41-first throttling channel; 42-second throttling channel; 43-first one-way valve; 44-second one-way valve; 5-buffer sleeve; 51-throttling pipeline; 52-guide part; 53-transition slope; 6-buffer column; 7-lower mounting seat; 8-elastic member; 91-seat assembly; 92-bladder skin; 93-piston cylinder; 94-air chamber; 95-sealing ring; 96-spring seat. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0034] As attached Figure 1-6As shown, a hydraulic shock absorber comprises an outer cylinder 1, an inner cylinder 2 and a piston rod 3 arranged from outside to inside, a compensation chamber 11 is provided between the outer cylinder 1 and the inner cylinder 2; the lower end of the piston rod 3 is located in the inner cylinder 2 and a piston 4 is provided at the lower end of the piston rod 3, the piston 4 divides the inner chamber of the inner cylinder 2 into an upper chamber 21 and a lower chamber 22; the piston 4 is provided with a first throttling channel 41 and a second throttling channel 42 communicating with the upper chamber 21 and the lower chamber 22, the first throttling channel 41 is provided with a first one-way valve 43 leading to the upper chamber 21, and the second throttling channel 42 is provided with a second one-way valve 44 leading to the lower chamber 22; the bottom wall of the inner cylinder 2 is provided with a third throttling channel 23 and a fourth throttling channel 24 communicating with the lower chamber 22 and the compensation chamber 11, the third throttling channel 23 is provided with a first one-way valve 43 leading to the compensation chamber 22, and the second one-way valve 44 leading to the compensation chamber 22. The third one-way valve 25 of the cavity 11, the fourth one-way valve 26 leading to the lower chamber 22 is provided on the fourth throttling channel 24; the lower chamber 22 is provided with a buffer sleeve 5 and a buffer column 6 which are coaxially arranged up and down, the buffer sleeve 5 is connected to the piston 4, and the lower ports of the first throttling channel 41 and the second throttling channel 42 are both located in the cavity of the buffer sleeve 5; the buffer column 6 is fixedly arranged at the bottom of the lower chamber 22; a throttling pipeline 51 which passes through the inside and outside is provided on the wall of the buffer sleeve 5; the piston 4 is used to drive the buffer sleeve 5 to reciprocate axially up and down so that the upper end of the buffer column 6 enters and exits the buffer sleeve 5; when the buffer sleeve 5 moves to the lower limit position, the buffer column 6 is located in the cavity of the buffer sleeve 5 and is clearance-matched with it, and the side wall of the buffer column 6 blocks all the inner ports of the throttling pipeline 51. The inner port of the throttling pipeline 51 is located on the inner wall of the buffer sleeve 5, and the outer port of the throttling pipeline 51 is located on the outer wall of the buffer sleeve 5. The total flow cross-section area of ​​the throttling pipeline 51 should be smaller than the total flow cross-section area of ​​the first throttling channel 41, that is, when the oil flow rate is the same, the total flow of the throttling pipeline 51 is required to be smaller than the total flow of the first throttling pipeline 41 in the same time.

[0035] When a vehicle using the shock absorber of the present invention is normally driving on a flat road, Figure 1 , Figure 4 and Figure 6As shown, the upper chamber 21 and the lower chamber 22 of the shock absorber inner tube 2 are both filled with hydraulic oil. The up-and-down movement amplitude of the vehicle body relative to the wheel is within the specified range. The vehicle body drives the piston rod 3 and the piston 4 to move up and down synchronously. The buffer column 6 is always located outside the cavity of the buffer sleeve 5 and arranged with a spacing therefrom. When the vehicle body drives the piston rod 3 and the piston 4 to move upward synchronously, the piston 4 squeezes the upper chamber 21 to increase the oil pressure inside it. The high-pressure oil in the upper chamber 21 pushes open the valve plate of the second one-way valve 44 on the second throttling channel 42 and flows into the lower chamber 22. The second throttling channel 42 limits the flow of oil flowing from the upper chamber 21 to the lower chamber 22, providing damping force for the upward pull of the piston rod 3 and the piston 4, and ensuring that the piston rod 3 and the piston 4 move slowly upward. When the vehicle body drives the piston rod 3 and the piston 4 to move downward synchronously, the piston 4 squeezes the lower chamber 22 to increase the oil pressure inside it. The oil outside the buffer sleeve 5 in the lower chamber 22 enters the inner cavity of the buffer sleeve 5 through the lower port of the buffer sleeve 5 and the throttling pipeline 51, and then pushes open the valve plate of the first one-way valve 43 on the first throttling channel 41 to enter the upper chamber 21. The first throttling channel 41 limits the flow of oil from the lower chamber 22 to the upper chamber 21, providing damping force for the downward movement of the piston rod 3 and the piston 4, so that the piston rod 3 and the piston 4 move downward slowly. The hydraulic oil circulates between the upper chamber 21 and the lower chamber 22 through the first throttling channel 41 and the second throttling channel 42 to generate damping force, providing buffering for the movement of the piston rod 3.

[0036] When a vehicle is driving on an uneven road or in emergency braking, the relative movement of the vehicle body and wheels in the up and down directions is relatively large. Figure 2-3As shown, when the vehicle body drives the piston rod 3 and the piston 4 to be compressed downward beyond the specified range, the piston 4 drives the buffer sleeve 5 to move downward so that the upper end of the buffer column 6 located at the bottom of the lower chamber 2 enters the buffer sleeve 5. At this time, the buffer column 6 blocks the lower port of the buffer sleeve 5, and the outer wall of the buffer sleeve 5, the side wall of the buffer column 6 located outside the buffer sleeve 5 and the side wall of the lower chamber 22 form an annular cavity 211. Because the gap between the buffer column 6 and the buffer sleeve 5 is extremely small, the oil in the annular cavity 211 mainly enters the inner cavity of the buffer sleeve 5 through the throttling line 51, and the oil in the inner cavity of the buffer sleeve 5 enters the upper chamber 21 through the first throttling channel 41. The throttling line 51 limits the flow of oil entering the inner cavity of the buffer sleeve 5, and indirectly limits the flow of oil entering the first throttling channel 41, further slowing down the speed of oil entering the upper chamber 21 from the lower chamber 22, providing greater damping force for the downward movement of the piston rod 3 and the piston 4, and further playing a buffering role for the piston and the piston rod. If the vehicle body continues to drive the piston rod 3, the piston 4 and the buffer sleeve 5 to move downward, when the outer side surface of the buffer column 6 blocks the inner port of the throttling line 51, the buffer column 6 limits the flow of oil entering the cavity of the buffer sleeve 5 from the throttling line 51, and indirectly limits the flow of oil entering the first throttling channel 41, further slowing down the speed of the oil entering the upper chamber 21 from the lower chamber 22, and further increasing the damping force provided for the downward movement of the piston 4 and the piston rod 3, thereby preventing the piston 4 from continuing to move downward, causing the buffer sleeve 5 to collide with the bottom wall of the lower chamber 22 rigidly, causing damage to the shock absorber, and improving the shock absorption performance of the shock absorber.

[0037] In the process from the buffer column 6 entering the buffer sleeve 5 to the buffer column 6 covering all the throttling pipes 51, when the oil pressure in the lower chamber 22 is too large, the hydraulic oil in the lower chamber 22 pushes open the valve plate of the third one-way valve 25 in the third throttling channel 23 on the bottom wall of the inner tube 2 and enters the compensation chamber 11. The third throttling channel 23 limits the flow of oil flowing from the lower chamber 22 to the compensation chamber 11, providing damping force for the piston 4 and the piston rod 3 to continue to move slowly downward, while preventing the oil pressure in the lower chamber 22 from being too large to damage the inner tube 2; on the contrary, when the vehicle body drives the piston rod 3 and the piston 4 to reset upward synchronously, the negative pressure in the lower chamber 22 is too large, and the oil in the compensation chamber 11 pushes open the fourth one-way valve 26 on the fourth throttling channel 24 and enters the lower chamber 22. The fourth throttling channel 24 limits the flow of oil flowing from the compensation chamber 11 to the lower chamber 22, causing the piston 4, the piston rod 3 and the buffer sleeve 5 to slowly pull up until the buffer column 6 is out of the buffer sleeve 5.

[0038] The outer cylinder 1 is used to install the cylinder of the shock absorber in the piston cylinder 9 of the air spring, and the inner cylinder 2 is used to accommodate the piston 4 and the piston rod 3, providing a telescopic movement space for the piston rod 3. The outer contour shape of the radial section of the piston 4 is adapted to the inner contour shape of the radial section of the inner cylinder 2 and has the same size. The two are interference fit, and the inner wall of the inner cylinder 2 is tightly fitted with the outer side of the piston 4 and radially limits the piston 4 to ensure the axial reciprocating movement of the piston 4 and the piston rod 3. The upper ports of the inner cylinder 2 and the outer cylinder 1 are both provided with a sealing end cover 12 with an axial through hole, and the piston rod 3 passes through the axial through hole on the sealing end cover 12 and is axially slidably sealed with the hole wall of the axial through hole. The piston 4 and the piston rod 3 can be welded or directly connected by threads, or can be connected by bolts, pins and other connecting parts. The first throttling channel 41, the second throttling channel 42, the third throttling channel 23 and the fourth throttling channel 24 can be straight pipes, or curved pipes with L-shaped, V-shaped, W-shaped and other structures.

[0039] The buffer sleeve 5 is used to cooperate with the buffer column 6 to adjust the number of oil paths entering the inner cavity of the buffer sleeve 5 from the annular cavity 211. The buffer sleeve 5 can be welded on the piston 4, and can also be connected to the piston 4 by bolts, pins and other connectors. Specifically, the lower part of the outer side surface of the piston 4 is provided with a limit groove perpendicular to its axis, and the buffer sleeve 5 is provided with a clamping block that matches the shape and size of the limit groove. The clamping block is located in the limit groove and axially clamped with the side wall of the groove. The two cooperate to limit the axial position of the punch sleeve 5, which is convenient for assembly. The piston 4 and the buffer sleeve 5 are not easy to disengage during the axial movement, and the connection is stable.

[0040] The buffer sleeve 5 can be a straight cylinder structure with the same axial outer diameter, or a conical cylinder structure with different axial outer diameters, which is in clearance fit with the inner cylinder 2. Preferably, the buffer sleeve 5 is provided with a guide portion 52 protruding from its outer side wall, and the guide portion 52 is in axial sliding fit with the inner cylinder 2; the guide portion 52 has an axially penetrating oil circuit. The guide portion 52 limits the buffer sleeve 5 radially to ensure the direction of axial movement of the buffer sleeve 5. The oil circuit on the guide portion 52 is used to connect the annular cavities 211 above and below it, thereby ensuring the unobstructed flow of the throttling pipeline 51. The guide portion 52 can be a ring structure, or it can be a plurality of protrusion structures evenly distributed along the circumference of the buffer sleeve 5.

[0041] The cavity in the buffer sleeve 5 can be a prism, a cylinder or a truncated cone. For the convenience of processing, the inner cavity of the buffer sleeve 5 is generally a cylindrical structure. Preferably, a transition slope 53 is provided between the bottom wall of the buffer sleeve 5 and the inner side wall of the buffer sleeve 5, which is radially arranged from the inside to the outside and tilted downward. When the upper end of the buffer column 6 begins to enter the inner cavity of the buffer sleeve 5, the annular gap between the buffer column 6 and the buffer sleeve 5 through which the oil can pass is gradually reduced, so as to avoid the sudden change of the cross section of the oil path connecting the annular cavity 221 and the inner cavity of the buffer sleeve 5, which may cause the buffer sleeve 5 to be subjected to severe impact of the oil pressure, thereby buffering the hydraulic pressure. In addition, the transition slope 53 also guides the buffer column 6 to enter the buffer sleeve 5, thereby ensuring the relative axial movement of the buffer column 6 and the buffer sleeve 5.

[0042] The buffer column 6 is used to control the opening and closing of the lower port of the buffer sleeve 5 and the port in the throttling line 51. The buffer column 6 can be a solid cylindrical structure or a hollow sleeve structure. The outer contour of the cross section of the buffer column 6 can be any shape. Generally speaking, the shape of the outer contour of the cross section of the buffer column 6 is the same as the cross-sectional shape of the inner cavity of the buffer sleeve 5 and the size is adapted. After the buffer column 6 enters the cavity of the buffer sleeve 5, the unilateral gap between the two is set according to the maximum compression damping force required by the shock absorber. In order to prevent the buffer column 6 from occupying too much space in the lower chamber 22, preferably, the buffer column 6 is a cylindrical structure with openings at both ends, which saves space in the lower chamber 22, reduces the volume and weight of the shock absorber, and facilitates assembly, disassembly and transportation.

[0043] The buffer column 6 can be connected to the bottom wall or side wall of the inner tube 2 by bolts, pins and other connectors, or can be directly welded in the inner tube 2. Preferably, a lower mounting seat 7 is provided on the bottom wall of the lower chamber 22, and the lower mounting seat 7 is interference fit with the inner tube 2; an axial step through hole is provided on the lower mounting seat 7, and the lower end of the buffer column 6 is inserted into the axial step through hole and interference fits therewith, and the lower end face of the buffer column 6 axially abuts against the step in the axial step through hole. The lower mounting seat 7 is fixedly mounted on the bottom wall of the lower chamber 22 by interference fit with the inner tube 2, and the buffer column 6 is radially positioned by interference fit with the step through hole on the lower mounting seat 7, and the step of the step hole is used to limit the axial position of the buffer column 6 to ensure the installation accuracy of the buffer column 6.

[0044] Preferably, the top surface of the lower mounting seat 7 is provided with an elastic member 8 aligned with the buffer sleeve 5. When the buffer sleeve 5 moves downward to squeeze the elastic member 8, the elastic member 8 is compressed and deformed while providing a damping force for the buffer sleeve 5 to buffer the buffer sleeve 5, thereby preventing the buffer sleeve 5 from rigidly colliding with the lower mounting seat 7 when it moves to the lower limit position, thereby improving the reliability of the shock absorber. The elastic member 8 can be a spring, or an elastic gasket or sleeve made of elastic materials such as PA66 and NBR.

[0045] The throttling line 51 on the buffer sleeve 5 can be provided with one or more. Preferably, the throttling line 51 is provided with multiple, and the multiple throttling lines 51 are evenly arranged along the circumference of the buffer sleeve 5. The axial positions of the inner ports of the multiple throttling lines 51 can be the same or different. As a further preference, the axial positions of the inner ports of the multiple throttling lines 51 are different, the greater the axial length of the buffer column 6 entering the buffer sleeve 5, the greater the number of throttling lines 51 with blocked inner ports, the greater the throttling degree of the oil entering the inner cavity of the buffer sleeve 5 from the annular cavity 221, and the greater the throttling degree of the oil entering the upper chamber 21 from the inner cavity of the buffer sleeve 5. Accordingly, the damping force on the downward movement of the piston 4 gradually increases, thereby improving the adjustment range and adjustment accuracy of the damping force of the piston 4 and improving the shock absorption capacity of the shock absorber. Multiple refers to at least two. The pipe diameters of the multiple throttling lines 51 can be the same or different.

[0046] The throttling pipeline 51 can be a through hole provided on the buffer sleeve 5, or a groove provided on the inner wall of the buffer sleeve 5. The outer port of the throttling pipeline 51 can be provided on the bottom wall of the buffer sleeve 5, or on the outer side wall of the buffer sleeve 5. Preferably, the throttling pipeline 51 is a plurality of strip grooves provided on the inner wall of the buffer sleeve 5, the length direction of the strip grooves is arranged along the axial direction of the buffer sleeve 5, the lower end of the strip grooves is open and the lower end opening is located on the bottom wall of the buffer sleeve 5; the throttling pipelines 51 of the plurality of strip groove structures have different lengths, the lower end opening of the strip grooves is the outer port of the throttling pipeline 51, and the radially inward opening of the strip grooves is the inner port, which has a simple structure and is convenient for processing. The groove depths of the throttling pipelines 51 of the plurality of strip groove structures can be the same or different; the groove widths of the throttling pipelines 51 of the plurality of strip groove structures can be the same or different.

[0047] As a further preferred embodiment, the groove depth and groove width of the throttling pipeline 51 of the strip groove structure gradually decrease from bottom to top. As the length of the buffer column 6 entering the buffer outer tube 5 increases, the inner port of the throttling pipeline 51 of the strip groove structure gradually decreases, and the diameter of the inner port is always smaller than the cross section of the pipeline 51. The throttling pipeline 51 has a greater and greater degree of flow restriction on the cavity of the buffer outer tube 5 entering the upper chamber 21. Correspondingly, the compression damping force on the piston 4 also gradually increases, further avoiding the piston 4 driving the buffer column 6 to collide with the bottom surface of the inner tube rigidly, thereby improving the vibration reduction performance of the shock absorber.

[0048] An air spring shock absorber assembly structure includes an air spring, the air spring includes a top seat assembly 91, a bladder skin 92 and a piston cylinder 93 arranged from top to bottom, one end of the bladder skin 92 is sealed and connected to the top seat assembly 91, the other end of the bladder skin 92 is sealed and connected to the piston cylinder 93, and the top seat assembly 91, the bladder skin 92 and the piston cylinder 93 form an air chamber 94; and also includes any of the above-mentioned hydraulic shock absorbers; the outer cylinder 1 of the shock absorber is installed in the air spring piston cylinder 93 and the two are sealed and connected, and the upper end of the shock absorber piston rod 3 passes through the air chamber 94 of the air spring and is sealed and connected to the top seat assembly 91 of the air spring. The top seat assembly 91 of the air spring and the bladder skin 92, and the piston cylinder 93 and the bladder skin 92 are generally connected by buckling rings. The top seat assembly 91 generally has an axial step through hole, and the upper end of the shock absorber piston rod 3 is fastened to the top seat assembly 91 through a nut after passing through the step through hole on the top seat assembly 91. The shock absorber outer tube 1 and the air spring piston tube 93 can be sealed and connected by a sealing ring 95. A spring seat 96 is generally provided on the shock absorber outer tube 1. The spring seat 96 is used to support the sealing ring 95 and the air spring piston tube 93 to axially limit the two on the shock absorber outer tube 1.

[0049] In the air spring shock absorber assembly structure described in the present invention, the shock absorber of the present invention can effectively prevent the piston rod 3 of the shock absorber from driving the piston 4 to move downward beyond a specified range and then rigidly colliding with the shock absorber inner tube 2. There is no need to set an elastic buffer block in the air spring chamber 94 to avoid interference between the elastic buffer block and the piston rod 3. The connection structure between the top seat assembly 91 of the air spring and the shock absorber piston rod 3 is simplified, saving the air chamber space of the air spring, reducing the total volume of the air spring, reducing the installation space required for the air spring, and facilitating the layout and installation of the overall structure of the vehicle suspension.

[0050] The terms "upper", "lower", "top" and "bottom" in the present invention are relative positions and cannot be understood as limitations on specific positions. The embodiments of this specific implementation are all preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydraulic shock absorber, comprising an outer cylinder (1), an inner cylinder (2) and a piston rod (3) arranged from outside to inside, wherein a compensation chamber (11) is provided between the outer cylinder (1) and the inner cylinder (2); the lower end of the piston rod (3) is located in the inner cylinder (2) and a piston (4) is provided at the lower end of the piston rod (3), wherein the piston (4) divides the inner cavity of the inner cylinder (2) into an upper cavity (21) and a lower cavity (22); the piston (4) is provided with a first throttling channel (41) and a second throttling channel (42) communicating with the upper cavity (21) and the lower cavity (22), wherein the first throttling channel The inner tube (2) is provided with a first one-way valve (43) leading to the upper chamber (21), and the second throttling passage (42) is provided with a second one-way valve (44) leading to the lower chamber (22); the bottom wall of the inner tube (2) is provided with a third throttling passage (23) and a fourth throttling passage (24) connecting the lower chamber (22) and the compensation chamber (11), the third throttling passage (23) is provided with a third one-way valve (25) leading to the compensation chamber (11), and the fourth throttling passage (24) is provided with a fourth one-way valve (26) leading to the lower chamber (22); the characteristics are: A buffer sleeve (5) and a buffer column (6) are coaxially arranged in an upper and lower direction in the lower chamber (22); the buffer sleeve (5) is connected to the piston (4); the lower ports of the first throttling channel (41) and the second throttling channel (42) are both located in the cavity of the buffer sleeve (5); the buffer column (6) is fixedly arranged at the bottom of the lower chamber (22); a throttling pipeline (51) penetrating inside and outside is provided on the wall of the buffer sleeve (5); The piston (4) is used to drive the buffer sleeve (5) to move axially up and down to reciprocate so that the upper end of the buffer column (6) moves in and out of the buffer sleeve (5); when the buffer sleeve (5) moves to the lower limit position, the buffer column (6) is located in the cavity of the buffer sleeve (5) and is loosely matched with it, and the side wall of the buffer column (6) blocks all inner ports of the throttling pipeline (51).

2. The hydraulic shock absorber according to claim 1, characterized in that: A limit slot perpendicular to the axis of the piston (4) is provided at the lower portion of the outer side surface thereof, and a clamping block having a shape and size matching that of the limit slot is provided on the buffer sleeve (5), the clamping block being located in the limit slot and axially clamped with the side wall of the slot; The buffer sleeve (5) is provided with a guide portion (52) protruding from its outer side wall, and the guide portion (52) is axially slidably matched with the inner tube (2); the guide portion (52) is provided with an axially penetrating oil passage.

3. The hydraulic shock absorber according to claim 1, characterized in that: A transition slope (53) is provided between the bottom wall of the buffer sleeve (5) and the inner side wall of the buffer sleeve (5), and is arranged obliquely downward from the inside to the outside.

4. The hydraulic shock absorber according to claim 1, characterized in that: The buffer column (6) is a cylindrical structure with openings at both ends.

5. The hydraulic shock absorber according to claim 1, characterized in that: A lower mounting seat (7) is provided on the bottom wall of the lower chamber (22), and the lower mounting seat (7) is interference fit with the inner tube (2); an axial step through hole is provided on the lower mounting seat (7), and the lower end of the buffer column (6) is inserted into the axial step through hole and interference fits therewith, and the lower end surface of the buffer column (6) is axially abutted against the step in the axial step through hole.

6. The hydraulic shock absorber according to claim 5, characterized in that: The top surface of the lower mounting seat (7) is provided with an elastic member (8) which is arranged vertically aligned with the buffer sleeve (5).

7. The hydraulic shock absorber according to claim 1, characterized in that: A plurality of the throttling pipelines (51) are provided, and the plurality of the throttling pipelines (51) are evenly arranged along the circumference of the buffer sleeve (5); and the axial positions of the inner ports of the plurality of the throttling pipelines (51) are different.

8. The hydraulic shock absorber according to claim 7, characterized in that: The throttling pipeline (51) is a plurality of strip grooves arranged on the inner wall of the buffer sleeve (5), the length direction of the strip grooves is arranged along the axial direction of the buffer sleeve (5), the lower ends of the strip grooves are open and the lower end openings are located on the bottom wall of the buffer sleeve (5); The throttling pipelines (51) of the plurality of strip-shaped groove structures have different lengths.

9. The hydraulic shock absorber according to claim 8, characterized in that: The groove depth and groove width of the throttling pipeline (51) of the strip groove structure gradually decrease from bottom to top.

10. An air spring shock absorber assembly structure, comprising an air spring, wherein the air spring comprises a top seat assembly (91), a bladder skin (92) and a piston cylinder (93) arranged from top to bottom, one end of the bladder skin (92) is sealedly connected to the top seat assembly (91), and the other end of the bladder skin (92) is sealedly connected to the piston cylinder (93), and the top seat assembly (91), the bladder skin (92) and the piston cylinder (93) enclose an air chamber (94); characterized in that: Also includes a hydraulic shock absorber as claimed in any one of claims 1 to 8; The outer cylinder (1) of the shock absorber is installed in the air spring piston cylinder (93) and the two are sealed and connected. The upper end of the shock absorber piston rod (3) passes through the air chamber (94) of the air spring and is sealed and connected to the top seat assembly (91) of the air spring.

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