Hydraulic shock absorber with step-by-step vehicle clearance adjustment

Abstract

FIELD: mechanical engineering.SUBSTANCE: hydraulic shock absorber with step-by-step adjustment of vehicle clearance comprises a tank, a working cylinder located in it, a piston rod, a compression valve, a rebound valve and a spring cup. At least two annular grooves are made on the outer surface of the tank. The grooves are located along the height of the tank. A retaining ring is installed in one of the grooves. The ring interacts with the groove of the spring cup, forming a stepped fixation of the position of the spring cup relative to the tank.EFFECT: reliable step-by-step adjustment of the spring support cup position without the use of threaded connections, increasing operational reliability and resistance to dirt and corrosion, as well as increasing the durability of the structure.10 cl, 3 dwg

Description

[0001] The technical solution relates to the field of mechanical engineering, primarily to vehicle suspensions, and can be used in the design of hydraulic shock absorbers with the ability to change the position of the spring support cup to adjust the vehicle's ground clearance and suspension stiffness.

[0002] An adjustable vehicle stabilizer is known (US3603575 A, published 09 / 07 / 1971), including a hydraulic shock absorber having a housing and an extendable piston rod, wherein both the housing and the piston rod are provided with fasteners, wherein the improvement includes: a. a hollow cylindrical housing for the shock absorber cylinder, part of the outer surface of which is threaded; b. a retaining device fixedly mounted on the distal end of the piston rod and moving together with it relative to the housing; c. an adjusting device screwed onto the threaded part of the housing and moving axially along it; and d. a coil spring embracing the housing and the piston rod and located between the retaining and adjusting devices, wherein its compression is determined by the adjustable axial movement of the spring.

[0003] A shock absorber spring adjuster is known (US5044614A, published 09 / 03 / 1991), including: a shock absorber unit containing a piston rod and a telescopically interacting tube, wherein said tube has an end protruding from it for fastening to a vehicle, a one-piece radially slotted retainer located near one of the ends of the piston rod, a separately and freely removable one-piece elongated tubular housing sleeve surrounding and adjacent to the end of said tube, wherein said sleeve has a smooth internal opening and opposite open ends, including upper and lower parts, wherein said housing sleeve contains sealing and damping elements located near said upper open end and between said inner opening and said shock absorber tube, means for fastening the housing sleeve, including parallel flanges located at a distance from each other,protruding from said bottom of said housing bushing, said flanges having through holes that allow for the overall fastening of said bottom of the housing bushing with the protruding end of the tube, an adjusting element surrounding said housing bushing, threaded connections connecting said adjusting element with said housing bushing, said threaded connections allowing for selective axial movement of said adjusting elements along said housing bushing, a helical spring having opposite ends that are respectively adjacent to said locks and adjusting elements, and surrounding said piston rod, tube and housing bushing, due to which the angular movement of said adjusting element alternately moves up and down relative to the housing bushing, respectively increasing or decreasing the effective length of the spring.

[0004] The disadvantages of known solutions are: susceptibility of the threaded connection to contamination and corrosion, wear of the threaded pair during long-term operation, the possibility of spontaneous displacement under vibration loads, complexity and labor-intensiveness of adjustment, the lack of fixed adjustment stages that ensure repeatability of settings.

[0005] The technical result achieved by implementing the proposed technical solution is to provide convenient and reliable step-by-step adjustment of the position of the spring support cup without the use of threaded connections, increasing operational reliability and resistance to dirt and corrosion, as well as increasing the durability of the structure.

[0006] To achieve the specified technical result, a hydraulic shock absorber with a step-by-step adjustment of the vehicle's ground clearance is proposed, comprising a reservoir, a working cylinder placed therein, a rod with a piston, a compression valve, a rebound valve and a spring cup, wherein at least two annular grooves are made on the outer surface of the reservoir, located along the height of the reservoir, while in one of the grooves a retaining ring is installed, interacting with a groove in the spring cup, with the formation of a step-by-step fixation of the position of the spring cup relative to the reservoir.

[0007] The reservoir is designed to accommodate the working cylinder, compensation cavity, and hydraulic fluid, as well as to support the loads from the vehicle's suspension. It is typically cylindrical in shape with a hermetically sealed bottom and an upper section mated with the piston rod guide. The reservoir's internal volume accommodates the working cylinder, creating a compensation cavity. Circular grooves are machined into the reservoir's outer surface for installing a retaining ring and stepwise securing the spring cup. The reservoir is manufactured as a seamless, drawn, or welded material from structural or alloy steels, or aluminum alloys with a protective coating. The groove area can be reinforced if necessary. This reservoir design ensures strength, tightness, and secure retention of the spring cup.

[0008] The working cylinder is used to direct the piston's movement and generate hydraulic resistance during compression and rebound strokes. It is located within the reservoir, creating a compensation cavity for the hydraulic fluid. The cylinder is manufactured as a thin-walled alloy steel tube with a precision-machined inner surface, such as honing, which reduces friction and ensures stable seal operation. This design ensures consistent damping characteristics and a tight hydraulic system.

[0009] The piston rod transmits force from the vehicle's suspension to the piston and then to the hydraulic fluid. It is a cylindrical rod, slidably mounted in a guide and passed through sealing elements. The piston rod is made of high-strength steel and can have a protective wear-resistant coating, such as chrome plating or nitriding. The use of such materials and coatings increases wear resistance, corrosion resistance, and durability of the component.

[0010] The piston is designed to create hydraulic resistance during piston rod movement. It is attached to the lower end of the piston rod and is equipped with bypass holes and valve elements. The piston is made of steel or aluminum alloys and is fitted with sealing rings or guide elements made of wear-resistant polymer materials. This piston design allows for the formation of specified damping characteristics during compression and rebound strokes.

[0011] The compression valve regulates the flow of working fluid during the shock absorber's compression stroke. It can be a disc, plate, or plate valve, using spring elements of varying stiffness. Spring and alloy steels are used for the compression valve, ensuring elasticity and durability. The compression valve's design allows for the desired suspension compression stiffness.

[0012] The rebound valve regulates fluid flow during the rebound stroke and stabilizes suspension movement. It is located in the piston or at the base of the working cylinder and is similar in design to the compression valve. The use of elastic discs and spring elements made of alloy steel in the rebound valve ensures stable operation and effective vibration damping.

[0013] The spring cup serves as a support element for the coil spring, transmitting its force to the shock absorber body and allowing for spring preload adjustment. The cup is a ring-shaped element with a central hole corresponding to the outer diameter of the reservoir, ensuring alignment. An annular groove is formed in the inner part for engagement with a retaining ring. The upper support surface forms a seat for the lower coil of the spring and can be flat, conical, or profiled to match the coil's geometry. The cup is stamped, cast, welded, or composite with a reinforcing insert. Drainage holes and stiffening ribs are added if necessary. Materials used include structural or alloy steels, as well as high-strength aluminum alloys with protective coatings.This design ensures reliable axial load support, precise positioning, and corrosion resistance. The interaction of the cup groove with the retaining ring creates a rigid, stepped locking system without the use of threaded connections.

[0014] At least two annular grooves, machined on the outer surface of the reservoir, are designed to accommodate the retaining ring and create fixed spring cup positions corresponding to different preload and vehicle ground clearance levels. The grooves are closed, annular, and are positioned perpendicular to the longitudinal axis of the shock absorber. The distance between the grooves determines the amount of change in spring preload and, consequently, the vehicle's ride height. The groove profile is radiused, rectangular, or trapezoidal and, if necessary, chamfered to facilitate ring installation. The depth and width of the grooves are selected to ensure a secure fit of the retaining ring and to support the transmitted axial load. The grooves are spaced equally or at variable intervals for more precise adjustment, and their number may exceed two to expand the adjustment range.The grooves are produced by mechanical processing, such as turning or milling, or by knurling. In the area of ​​the annular grooves, the reservoir wall can be locally strengthened through heat treatment, surface hardening, work hardening, or other plastic deformation methods. This strengthening can increase the material's resistance to plastic deformation when supporting axial spring loads and prevent groove deformation during operation. The presence of such grooves provides discrete, repeatable adjustment levels, prevents spontaneous cup displacement, and eliminates the need for threaded elements, which are susceptible to contamination and corrosion.

[0015] The retaining ring secures the spring cup in the selected groove and transfers axial load to the reservoir. It is designed as a resilient, split-type design, allowing for elastic expansion during installation. Mounting holes or projections may be provided for ease of installation. The outer surface of the ring engages the cup groove, while the inner surface rests on the walls of the reservoir groove. The ring can be made as a split Seger-type ring, a spiral-wound ring, or a reinforced version with increased thickness. Retaining rings are made from spring steel or stainless steel, heat-treated and coated with an anti-corrosion coating. Once installed, the ring absorbs the load from the cup and reliably transfers it to the reservoir.This solution provides rigid mechanical fixation of the spring cup without the use of threads, high vibration resistance, absence of spontaneous displacement, ease of installation and dismantling, as well as increased reliability and durability in conditions of contamination and corrosive exposure.

[0016] In a specific case, the reservoir may include a reservoir ring, which is an intermediate load-bearing element mounted under the spring cup and designed to transmit axial force and provide additional locking of the retaining ring. The reservoir ring is designed with an internal annular groove whose geometry matches the profile of the retaining ring. This design provides a secure grip on the retaining ring, limiting its radial expansion and preventing accidental release from the reservoir groove under high axial spring loads. Using a reservoir ring in the locking assembly allows for a more even distribution of stress in the contact zone and increases the overall mechanical strength and reliability of the step adjustment.

[0017] The proposed hydraulic shock absorber with step-by-step adjustment of vehicle ground clearance is disclosed in detail based on drawings representing its implementation.

[0018] Fig. 1 shows a general view of the hydraulic shock absorber in longitudinal section.

[0019] Fig. 2 - spring cup fixing unit.

[0020] Fig. 3 shows a variant of the design of the spring cup fixing unit, where:

[0021] 1 - tank,

[0022] 2 - working cylinder,

[0023] 3 - rod guide,

[0024] 4 - rod,

[0025] 5 - piston,

[0026] 6 - compression valve,

[0027] 7 - bottom of the tank,

[0028] 8 - retaining ring,

[0029] 9 - spring cup,

[0030] 10 - rod part,

[0031] 11 - piston part,

[0032] 12 - groove,

[0033] 13 - reservoir ring.

[0034] In a particular embodiment, a hydraulic shock absorber with a stepped adjustment of the vehicle ground clearance comprises a cylindrical reservoir 1, inside which a working cylinder 2 is located. A rod guide 3 is installed in the upper part of the working cylinder 2. A rod 4 is movably located in the central hole of the guide 3, at the lower end of which a piston 5 is fixed. A compression valve 6 is located in the lower part of the working cylinder 2. The bottom of the reservoir 7 is made sealed. Between the reservoir 1 and the working cylinder 2, a compensation cavity is formed, filled with the working shock absorber fluid. On the outer surface of the reservoir 1, annular grooves 12 are made, located symmetrically relative to the longitudinal axis of the shock absorber and spaced in height at a distance L. The number of grooves 12 is at least two. A retaining ring 8 is installed in one of the grooves 12. The spring cup 9 has an internal groove designed to interact with the retaining ring 8.The retaining ring 8 fixes the spring cup 9 in a given position relative to the reservoir 1.

[0035] The hydraulic shock absorber with stepped adjustment of the vehicle ground clearance operates as follows. During the compression stroke, the rod 4, together with the piston 5, performs a reciprocating downward movement. The working fluid from the piston part 11 flows through the bypass holes of the piston 5 into the rod part 10. The excess volume of fluid, arising due to the entrance of the rod 4 into the working cylinder 2, flows through the channels of the compression valve 6 into the compensation cavity between the reservoir 1 and the working cylinder 2, creating a compressive resistance force. During the rebound stroke, the rod 4 moves upward. The fluid from the rod part 10 flows through the holes in the piston 5 into the piston part 11, creating a rebound resistance force. Compensation for the change in fluid volume is performed through the compression valve 6. Adjustment is carried out as follows. To change the position of the spring cup 9, the load is removed from the suspension spring.Retaining ring 8 is removed from one groove 12 of reservoir 1 and installed in another groove 12, located either higher or lower. After installing retaining ring 8, spring cup 9 is positioned so that its groove engages retaining ring 8. Moving spring cup 9 upward increases the spring preload, which increases the vehicle's ground clearance and improves overall suspension rigidity. Moving spring cup 9 downward decreases the spring preload, lowering ground clearance and reducing suspension rigidity. The spring cup is securely fastened without a threaded connection, preventing spontaneous position changes.

[0036] In the second embodiment shown in Fig. 3, the spring cup 9 is provided with a profiled upper support surface having a bend corresponding to the shape of the lower coil of the spring. The said bend ensures partial coverage of the coil along its outer diameter and a more uniform distribution of the load from the spring. The reservoir ring 13, installed under the spring cup 9, is provided with an annular groove. The reservoir ring 13 is placed with abutment on the retaining ring 8 installed in the annular groove 12 of the reservoir 1. In this case, the groove of the reservoir ring 13 interacts with the retaining ring 8, limiting its radial opening and preventing the retaining ring 8 from exiting the groove 12 under the action of an axial load. When the shock absorber in the specified embodiment is operating, the load from the spring is perceived by the spring cup 9 and transmitted to the reservoir ring 13.The force is then transferred to the retaining ring 8, installed in the annular groove 12 of the reservoir 1, and through it to the wall of the reservoir 1. This sequential interaction of the elements ensures reliable transfer of the axial load to the reservoir 1 and rigid step-by-step fixation of the position of the spring cup 9 relative to the reservoir 1. Making the cup with a bend under the spring coil reduces local stresses in the contact zone, reduces the likelihood of spring distortion and increases the stability of the shock absorber when changing the position of the cup along the height of the reservoir.

[0037] At least two annular grooves, spaced apart in height, on the outer surface of the reservoir create a discrete mounting system. This, combined with a retaining ring and a mating groove in the spring cup, forms a rigid, force-locking system that allows the spring seat to be adjusted between fixed positions. This eliminates the risk of jamming or thread damage due to road dirt and corrosion, which is critical for a unit operating in aggressive environments. This directly increases the operational reliability and durability of the design. Since the spring load is transferred through the cup to the retaining ring, deeply seated in the reservoir groove, a secure position is achieved without the possibility of spontaneous displacement. The grooves, at different heights, provide easy stepwise adjustment of the spring clearance by simply moving the ring into the desired groove.

Claims

1. A hydraulic shock absorber with step-by-step adjustment of the vehicle's ground clearance, comprising a reservoir, a working cylinder placed therein, a rod with a piston, a compression valve, a rebound valve and a spring cup, characterized in that at least two annular grooves are made on the outer surface of the reservoir, located along the height of the reservoir, while in one of the grooves a retaining ring is installed, interacting with a groove in the spring cup, with the formation of a stepped fixation of the position of the spring cup relative to the reservoir.

2. The shock absorber according to paragraph 1, characterized in that the spring cup is made of stamped sheet structural or alloy steel to form an annular support belt for the lower coil of the spring.

3. The shock absorber according to paragraph 1, characterized in that the spring cup is provided with stiffening ribs made along its outer surface.

4. The shock absorber according to paragraph 1, characterized in that the spring cup is made with drainage holes for removing moisture and dirt.

5. The shock absorber according to paragraph 1, characterized in that the annular grooves are made with a radius, or rectangular, or trapezoidal profile.

6. The shock absorber according to paragraph 1, characterized in that in the area of ​​the annular grooves the wall of the reservoir is made with local strengthening.

7. The shock absorber according to item 1, characterized in that the annular grooves are located at a variable pitch along the height of the reservoir.

8. The shock absorber according to paragraph 1, characterized in that the retaining ring is made in the form of a spiral wound ring made of spring or stainless steel with heat treatment and an anti-corrosion coating.

9. The shock absorber according to paragraph 1, characterized in that the retaining ring is provided with mounting holes or protrusions for its installation and removal.

10. The shock absorber according to claim 1, characterized in that the reservoir contains a reservoir ring made with an internal annular groove and installed under the spring cup.

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