HYDRO BUSHING

A hydro bushing includes a main body configured for absorbing shocks using a sealed fluid; a side stopper including a shock absorber and having a hollow cylindrical structure; and a housing fixing the side stopper and the main body, wherein the main body and the side stopper are separable from each other.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to Korean Patent Application No. 10-2022-0174284 filed on Dec. 14, 2022, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE PRESENT DISCLOSURE

Field of the Present Disclosure

The present disclosure relates to a hydro bushing.

Description of Related Art

A suspension system of a vehicle may be a device that absorbs shocks or vibrations generated while driving so that the shocks or vibrations are not directly transmitted to a vehicle body or an occupant to affect ride and stability of the vehicle. A suspension system applied to a vehicle may be a MacPherson strut, a double wishbone, a multilink, a coupled torsion beam axle (CTBA), or the like, depending on a structure thereof.

In the instant case, the CTBA may be applied to many vehicles due to advantages thereof, such as a simple structure, a small number of components, and a small occupation space. The CTBA may be provided with a bushing having an elastic modulus in a site of being coupled to a vehicle body to provide a more comfortable ride by buffering some of load or vibrations generated in front and rear directions of a vehicle.

The bushing may act as using elastic deformation thereof to absorb shocks, vibrations, noise, or the like generated by a suspension or an engine, along with a role of supporting the CTBA and a body-side connection portion.

Recently, a hydro bushing sealing a fluid capable of implementing an active shock absorber function to have appropriate degree of rigidity suitable for driving conditions of a vehicle has been developed and provided. However, because the conventional hydro bushing may be manufactured as an integral type bushing, there may be problems such as crack propagation, a difficulty in improving performance, or the like.

BRIEF SUMMARY

Various aspects of the present disclosure are directed to providing a hydro bushing for fixing by separately manufacturing a side stopper and a main body.

According to an aspect of the present disclosure, a hydro bushing includes a main body configured for absorbing shocks using a sealed fluid; a side stopper including a shock absorber and having a hollow cylindrical structure; and a housing fixing the side stopper and the main body, wherein the main body and the side stopper are separable from each other.

The side stopper may include an upper plate and a lower plate, including a disk shape, wherein the shock absorber may be disposed and coupled between the upper plate and the lower plate, and wherein the upper plate, the lower plate, and the shock absorber may form an internal hole.

The main body may include an internal pipe formed to protrude to one side thereof, and a protrusion of the internal pipe may be inserted into the internal hole of the side stopper.

The internal pipe may protrude as long as a sum of a thickness of the lower plate of the side stopper and a thickness of the shock absorber.

An internal hole of at least one of the upper plate, the lower plate, or the shock absorber may have a diameter, different from a diameter of a remaining internal hole.

The diameter of the internal hole formed in the lower plate and the shock absorber may be at least wider than an external diameter of the internal pipe.

The diameter of the internal hole formed in the upper plate may be narrower than the external diameter of the internal pipe, and an end portion of the internal pipe may be in contact with and supported by the upper plate.

The upper plate may further include a first protrusion protruding toward the shock absorber on a portion of the lower surface.

The housing may further include a curled portion bent in a “U” shape surrounding a surface of an external circumference of the lower plate of the side stopper.

The main body may be coupled in a fluid. The main body may include a hollow cylindrical internal pipe including an anti-vibration unit absorbing vibrations externally; an external pipe surrounding the internal pipe and sealing a fluid in an internal space formed with an external surface of the internal pipe; and a middle pipe forming a movement path of the fluid therein.

The middle pipe may be in an internal contact with the internal pipe, and may be in external contact with the external pipe.

The middle pipe may form an upper swaging and a lower swaging, bent outward, on both end portions in a longitudinal direction, wherein the upper swaging and the lower swaging are in an internal contact with the external pipe.

The middle pipe may further include an auxiliary stopper protruding onto an opposite side of the side stopper.

The auxiliary stopper may further include a second protrusion including an embossed structure.

An anti-vibration unit of the main body and a shock absorber of the side stopper may be formed of different materials.

In the figures, reference numbers refer to a same or equivalent parts of the present disclosure throughout the several figures of the drawing.

DETAILED DESCRIPTION

Because the present disclosure may have various changes and may have various exemplary embodiments of the present disclosure, specific embodiments may be illustrated in the drawings and described in detail. However, this may not be intended to limit the present disclosure to specific embodiments, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present disclosure.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms may be used only for distinguishing one component from another. For example, without departing from the scope of the present disclosure, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The term “and/or” may include a combination of a plurality of related listed items or any of a plurality of related listed items.

The terms used in the present application may be only used to describe specific embodiments, and may not be intended to limit the present disclosure. The singular expression may include the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” may be intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features. It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, include the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, various embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings.

FIG.1is a view exemplarily illustrating a coupled torsion beam axle (CTBA)20to which a hydro bushing10is mounted according to an exemplary embodiment of the present disclosure.

The CTBA20may include a torsion beam21, a trailing arm22, a spring seat23, a shock absorber bracket24, and a hydro bushing10.

The torsion beam21may be disposed to extend between a left wheel and a right wheel in a width direction of a vehicle body. For example, the torsion beam21may be mounted on a left rear wheel and a right rear wheel, but is not limited thereto. The torsion beam21may be provided on left and right sides using torsional elastic force, and may suppress independent movement of the trailing arm22to which the wheels of the vehicle body are connected, by the elastic force.

The trailing arms22may be provided on both end portions of the torsion beam21in a longitudinal direction of the vehicle body. A spindle bracket25for mounting the wheels of the vehicle body may be fixed to external side surfaces of the trailing arm22in the width direction of the vehicle body. The trailing arm22may be coupled to the spring seat23to which a spring is mounted, and to the shock absorber bracket24to which a shock absorber is mounted, and may support the spring seat23and the shock absorber bracket24.

The trailing arm22may be supported on the vehicle body through the hydro bushing10provided on a front end portion of the vehicle body of the trailing arm22. When vibrations or shocks are generated in the vehicle body, vibrations or shocks transmitted from a ground to the vehicle body may be absorbed by the spring and the shock absorber. Furthermore, the hydro bushing10may prevent vibrations and shocks from being transmitted to the vehicle body by controlling the vibrations and shocks. The hydro bushing10may prevent vibrations and shocks from being transmitted to the vehicle body by use of viscosity of fluid and buffering properties of rubber.

A hydro bushing10according to an exemplary embodiment of the present disclosure may have a configuration in which a side stopper and a main body are coupled by a housing. A hydro bushing10according to the related art may have a side stopper and a main body which may be integrated. In the case that a crack occurs in the side stopper of the integrated hydro bushing10, there may be a problem that the crack may propagate toward the main body. Furthermore, although efforts are being made to improve durability of the side stopper by increasing hardness of a material (e.g., rubber) for the integrated hydro bushing10, there may be a problem that performance of the hydro bushing10absorbing vibrations and shock may deteriorate. A side stopper and a main body may be manufactured separately and may thus be individually optimized according to each function and purpose thereof in a hydro bushing10according to an exemplary embodiment of the present disclosure. Therefore, durability of the hydro bushing10may also be improved, together with functionality thereof.

FIG.2is a perspective view of a hydro bushing according to an exemplary embodiment of the present disclosure,FIG.3is a cross-sectional view ofFIG.2, taken along line I-I′.FIG.4is a cross-sectional view ofFIG.2, taken along line II-II′, andFIG.5is an exploded view of a hydro bushing according to an exemplary embodiment of the present disclosure.

Referring toFIG.2,FIG.3,FIG.4andFIG.5, a hydro bushing10according to an exemplary embodiment of the present disclosure may include a side stopper100, a main body200, and a housing300.

The side stopper100may include an upper plate110, a lower plate130, and a shock absorber120provided between the upper plate110and the lower plate130. The side stopper100may include a toroid shape including a hole in a center portion thereof.

The upper plate110may be a circular plate including a hole in a center portion thereof. The hole in the center portion may be at least smaller than an external diameter of an internal pipe210. At least a portion of the upper plate110may not have a constant thickness in a section between an external circumference and an internal circumference. For example, the internal circumference and the external circumference in the upper plate110may have approximately the same thickness, and in the section between the internal circumference and the external circumference, the upper plate110may protrude downwardly from a lower surface thereof joined to the shock absorber120, to have a relatively thick thickness. In the instant case, a portion protruding from the lower surface of the upper plate110may be referred to as a first protrusion111. Because the upper plate110includes the first protrusion111, effects of more securely coupling the shock absorber120to the lower surface of the upper plate110and increasing stiffness against shocks in left and right directions may be effectuated. Furthermore, because the upper plate110includes the first protrusion111, hardness of the shock absorber120may be reduced. As the hardness of the shock absorber120is reduced, an effect of buffering the side stopper100may increase. Therefore, noise, vibrations, and harshness (NVH) performance of the hydro bushing10may be improved.

The lower plate130may be formed to oppose the upper plate110, and like the upper plate110, may include a toroid shape including a hole in a center portion thereof. Unlike the internal hole of the upper plate110, the internal hole of the lower plate130may be greater than the external diameter of the internal pipe210. An upper surface of the lower plate130may be coupled to the shock absorber120. The upper surface of the lower plate130may be coupled to the shock absorber120at a predetermined interval from an external circumference thereof. A surface of the external circumference of the lower plate130may be connected to surround a curled portion310including a “U” shape in the housing300, which is described later.

The shock absorber120may be provided between the upper plate110and the lower plate130. Like the upper plate110and the lower plate130, the shock absorber120may have a toroid shape including a hole in a center portion thereof. Also, unlike the internal hole of the upper plate110, the internal hole of the shock absorber120may be greater than the external diameter of the internal pipe210. The shock absorber120may be formed of a material having predetermined elasticity, such as rubber or a synthetic resin.

The main body200may include an internal pipe210, a middle pipe220, an external pipe230, and an anti-vibration unit240.

The internal pipe210may be coupled to the anti-vibration unit240on an external side surface thereof, and may have a hollow shape to be coupled to a frame of the vehicle body. One side of the internal pipe210may protrude as long as a thickness of the side stopper100so that the internal pipe210is inserted into and coupled to the side stopper100, and is coupled to the anti-vibration unit240. The internal pipe210may be coupled to the housing300, in a state in which the internal pipe210is inserted into the internal hole of the side stopper100, and the side stopper100may be fixed to the vehicle body, together with the main body200. In the instant case, the internal pipe210may be formed to protrude as long as the sum of a thickness of the lower plate130of the side stopper100and a thickness of the shock absorber120, and may be inserted into the side stopper100. For example, the internal pipe210may protrude so that a surface of an end portion of the internal pipe210inserted into the side stopper100is in contact with the upper plate110of the side stopper100. When a length of the internal pipe210to be protruded is longer than the sum of the thickness of the lower plate130and the thickness of the shock absorber120in the side stopper100, the end portion of the internal pipe210, when coupled to the side stopper100, may apply a force to push the upper plate110in an outward direction so that the upper plate110is deformed or contact between the upper plate110and the shock absorber120is weakened. When a length of the internal pipe210to be protruded is narrower than the sum of the thickness of the lower plate130and the thickness of the shock absorber120in the side stopper100, in a distance in which the end portion of the internal pipe210and the upper plate110are spaced from each other, the internal pipe210may move relatively freely until the internal pipe210comes into contact with the upper plate110so that performance of the side stopper100and performance of the hydro bushing10may deteriorate in the spaced distance.

The anti-vibration unit240may be provided between the internal pipe210and the middle pipe220, and may be formed of a material such as rubber or a synthetic resin, having elasticity, to absorb shock and vibration generated from the side stopper100or the internal pipe210. Furthermore, the anti-vibration unit240may form a liquid chamber250for supporting displacement of the internal pipe210, to absorb the shock and the vibration generated from the internal pipe210more effectively and stably join with the internal pipe210. The anti-vibration unit240may further include a movement limiting unit260, in a space in which the liquid chamber250and the internal pipe210are spaced from each other, to prevent a breakdown of the liquid chamber250by excessive displacement of the internal pipe210. The movement limiting unit260may be inserted into the space formed by the liquid chamber250to support the liquid chamber250, to secure a damping force of the liquid chamber250. The movement limiting unit260may be provided between the anti-vibration unit240and the internal pipe210, to prevent the excessive displacement of the internal pipe210and support the internal pipe210in the liquid chamber250at the same time so that shock and vibration are smoothly absorbed.

The middle pipe220may include an opening corresponding to the liquid chamber250, and the opening may pass through the middle pipe220. An upper swaging223and a lower swaging224, bent outward, may be formed on both end portions of the middle pipe220in a longitudinal direction thereof. The upper swaging223and the lower swaging224may be formed to include an annular shape in a circumferential direction of the middle pipe220.

An auxiliary stopper221may be further included on one side of the middle pipe220. The auxiliary stopper221may be provided on the one side of the middle pipe220in a direction, opposing the side stopper100. The auxiliary stopper221may control displacement, together with the side stopper100, when a heavy load acts on the hydro bushing10. The side stopper100and the auxiliary stopper221may control the displacement from both sides, to reduce a load of the shock absorber120and improve durability of the hydro bushing10.

In the instant case, the auxiliary stopper221may further include a plurality of second protrusions222protruding to have a shape, similar to embossment. As described above, the auxiliary stopper221may further include a second protrusion222including a plurality of protruded portions such as embossment. The auxiliary stopper221may improve the durability of the hydro bushing10, but may generate noise such as allophone or the like due to friction with the vehicle body, or the like, to reduce noise, vibration, and harshness (NVH) performance of the hydro bushing10. The second protrusion222may be further included in the auxiliary stopper221, to include an effect of reducing the generation of noise to improve the NVH performance of the hydro bushing10.

The external pipe230may be coupled to the middle pipe220through an internal side surface thereof, and may have a hollow cylindrical shape. The external pipe230may be in an internal contact with the upper swaging223and lower swaging224of the middle pipe220, to seal the middle pipe220. The external pipe230may seal the middle pipe220so that fluid is stored between the external pipe230and the internal pipe210, and the fluid moves between an inside and an outside of the middle pipe220. In the instant case, the external pipe230may be coupled to an assembly of the internal pipe210and the middle pipe220in a state in which the external pipe230is submerged in the fluid (e.g., a damping oil) of the hydro bushing10. For example, instead of separately injecting the fluid after assembling the hydro bushing10, the fluid may be stored in the main body200by coupling the external pipe230in a state in which the fluid is contained therein. Furthermore, the hydro bushing10may be provided by coupling the main body200and the side stopper100in which the fluid is stored, through the housing300, to improve performance of sealing the fluid by the hydro bushing10.

The housing300may be formed as a hollow cylinder, and may couple the side stopper100and the main body200. In the housing300, a lower hollow hole may be smaller than the external diameter of the external pipe230of the main body200, and an upper hollow hole may be smaller than the external diameter of the lower plate130of the side stopper100. The housing300may further include a curled portion310bent in a “U” shape. The curled portion310formed along a circumferential surface on one side of the housing300may press the lower plate130toward the main body200to couple the side stopper100and the main body200, in a state in which an edge portion of the lower plate130having a hollow disk shape is disposed on an internal side of the “U” shape.

In a conventional hydro bushing10, a side stopper100may be directly coupled through an internal pipe210, but a hydro bushing10according to an exemplary embodiment of the present disclosure may have a configuration in which the side stopper100and the main body200are formed separately and the side stopper100and the main body200are restrained by the housing300. Therefore, the side stopper100and the main body200may be formed of separate materials, or may be designed to conform each characteristic, and may be then assembled through the housing300. For example, when a conventional hydro bushing10increases hardness of a material of a shock absorber120to increase durability of a side stopper100, a main body200including an internal pipe210to be integrally formed may be also affected to lower NVH or to transmit a crack in the shock absorber to the main body200. In particular, in the shock absorber120, an increase in durability may conversely deteriorate the NVH performance. Therefore, there may be a problem occurring in inverse proportion to each other. In a hydro bushing10according to an exemplary embodiment of the present disclosure, the side stopper100and the main body200may be separately manufactured, and the side stopper100and the main body200may be coupled through the housing300, not to transmit a crack of the side stopper100to the main body200. A hydro bushing10according to an exemplary embodiment of the present disclosure may improve durability and NVH performance at the same time, as the side stopper100and the main body are separately designed. For example, the NVH performance may be improved by use of a material of high elasticity for the shock absorber120of the side stopper100, and the durability may be improved by use of a material resistant to fatigue, as a material of the main body200.

According to an exemplary embodiment of the present disclosure, because a side stopper and a main body of a separable hydro bushing are improved, respectively, the side stopper and the main body may be designed and combined according to characteristics of a vehicle.

Furthermore, according to an exemplary embodiment of the present disclosure, a crack generated in a side stopper may not propagate to a main body.

Furthermore, according to an exemplary embodiment of the present disclosure, noise, vibration, and harshness (NVH) performance may be improved by enhancing performance of a side stopper and performance of a main body.