CN209781554U - Hydraulic bushing - Google Patents

Abstract

The utility model provides a hydraulic pressure bush, include: a mandrel; a sleeve-shaped first flow channel body which is arranged on the mandrel in a sleeved mode, a first rubber body is filled in a gap between the mandrel and the first flow channel body, a first flow channel for hydraulic fluid is formed on the outer surface of the first flow channel body, two main liquid cavities for containing the hydraulic fluid are formed on the first rubber body in a radial direction and oppositely and are communicated with each other through the first flow channel; the outer sleeve is sleeved on the radial outer side of the first runner body in a pressing mode; and a seal assembly disposed axially outwardly of at least one of the first fluid passageways and defining, in cooperation with the outer sleeve, an auxiliary fluid chamber for containing hydraulic fluid. The seal assembly includes a support ring disposed over the mandrel and including a radial projection disposed within the auxiliary fluid chamber. The radial projection is in sealing contact with the inner surface of the outer sleeve, thereby dividing the auxiliary liquid chamber into a first sub-chamber axially outward and a second sub-chamber axially inward.

Description

Hydraulic bushing

Technical Field

The utility model relates to a hydraulic pressure bush for vehicle, especially rail vehicle.

Background

A hydraulic bushing is a part widely used in vehicles (e.g., automobiles and railway vehicles), and is mainly installed on a suspension or a bogie of a vehicle to absorb vibration and impact, thereby improving the stability and safety of the vehicle in running.

Chinese patent document CN108150536A discloses a hydraulic bushing. The hydraulic bushing comprises a mandrel, a first flow channel body and an outer sleeve, wherein the first flow channel body is sleeved on the outer side of the mandrel, and the outer sleeve is sleeved on the outer side of the first flow channel body in a pressing mode. A gap between the mandrel and the first fluid is filled with a first rubber body, and a groove is formed on the outer surface of the first fluid. Two liquid cavities for containing liquid are oppositely and radially constructed on the first rubber body, wherein the groove and the outer sleeve enclose a flow channel, and the two liquid cavities are communicated through the flow channel. The rigidity of the hydraulic bushing can be adjusted by the fluidity between the hydraulic fluid in the two fluid chambers, thereby achieving an improvement in the stability of the vehicle when running, particularly when the vehicle is turning.

However, in the above-described hydraulic bushing, the range of stiffness and damping adjustment thereof is still limited. Accordingly, it is desirable in the art to provide a hydraulic bushing having a stiffness and damping that can be varied over a greater range to provide greater ride stability and safety for the vehicle.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a novel hydraulic pressure bush, it can all realize the function of becoming rigidity in radial and axial.

According to the utility model discloses, a hydraulic pressure bush is provided, include: a mandrel; a sleeve-shaped first fluid channel which is arranged on the mandrel in a sleeved manner, a first rubber body is filled in a gap between the mandrel and the first fluid channel, a first fluid channel for hydraulic fluid is formed on the outer surface of the first fluid channel, two main fluid cavities for containing hydraulic fluid are formed on the first rubber body in a radial direction and oppositely, and the two main fluid cavities are communicated with each other through the first fluid channel; the outer sleeve is sleeved on the radial outer side of the first runner body in a pressing mode; and a seal assembly disposed axially outwardly of at least one of the first flow passage bodies, the seal assembly and the outer sleeve collectively defining an auxiliary fluid chamber for containing hydraulic fluid. Wherein, seal assembly establishes including the cover the epaxial support ring of dabber, the support ring includes being in the radial protruding portion in the auxiliary liquid chamber, radial protruding portion with the interior surface sealed contact of overcoat, thereby will the auxiliary liquid chamber is separated into the first subchamber that is in the axial outside and the second subchamber of axial inboard.

In a preferred embodiment, the support ring comprises a second flow passage for communicating the first and second subchambers of the auxiliary liquid chamber with each other.

In a preferred embodiment, the second flow passage is formed by a continuous groove formed on the inner surface of the support ring, wherein a first end of the groove, axially outside, is connected to the first sub-chamber and a second end, axially inside, is connected to the second sub-chamber.

in a preferred embodiment, a hydraulic fluid filling channel is provided in the support ring for filling the auxiliary fluid chamber with hydraulic fluid.

In a preferred embodiment, the hydraulic fluid filling channel comprises a horizontal branch leading to the axially outer end of the support ring, and a vertical branch leading to the first sub-chamber of the auxiliary liquid chamber.

In a preferred embodiment, a first end of said groove is connected to said first subchamber by a vertical branch of said hydraulic fluid filling channel.

in a preferred embodiment, said support ring further comprises an auxiliary rubber body vulcanized thereon, such that said radial projections are in sealing contact with the inner surface of said outer sleeve through said auxiliary rubber body.

In a preferred embodiment, said auxiliary rubber body comprises a first portion for making sealing contact with an axial end of said flow channel body, a second portion for making sealing contact with an axial end of said outer casing, and a third portion for making sealing contact with an inner surface of said outer casing, wherein said third portion is axially between said first and second portions.

In a preferred embodiment, rigid shims are embedded in both the first and second portions of the auxiliary rubber body.

In a preferred embodiment, the cross-sectional area and length of the first flow passage are determined in accordance with the required radial dynamic stiffness of the hydraulic bushing, and the cross-sectional area and length of the second flow passage are determined in accordance with the required axial dynamic stiffness of the hydraulic bushing.

According to the utility model discloses a hydraulic pressure bush all has the variable stiffness characteristic in the axial and footpath, and the degree that its rigidity changes is relevant with excitation amplitude and frequency. Due to the existence of the auxiliary liquid cavity, the damping effect of the hydraulic bushing in the axial direction is improved, and a better vibration reduction effect is achieved. Meanwhile, the communication between the auxiliary fluid chambers of the hydraulic bushing is realized through the second flow passage arranged on the support ring, so that no additional part needs to be arranged in the auxiliary fluid chambers. This makes full use of the space within the auxiliary fluid chamber and further enhances the stiffening effect provided by the hydraulic bushing.

Drawings

The present invention will be described in more detail hereinafter based on embodiments and with reference to the accompanying drawings. Wherein:

Fig. 1 schematically shows a cross-sectional view of a hydraulic bushing according to an embodiment of the invention.

FIG. 2 is an enlarged view showing the auxiliary fluid chamber area in the hydraulic bushing shown in FIG. 1.

Fig. 3 shows the structure of the support ring with unvulcanized rubber body, in particular the hydraulic fluid filling channels and the second flow channels in the support ring.

In the drawings, like parts are denoted by like reference numerals. The figures are not drawn to scale.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings. It should be noted that the terms "axial" and "radial" in this document refer to the horizontal and vertical directions in fig. 1, respectively.

Fig. 1 schematically shows a hydraulic bushing 100 according to an embodiment of the invention. As shown in fig. 1, the hydraulic bushing 100 includes a core shaft 10, a first flow passage body 20 disposed radially outside the core shaft 10, and an outer sleeve 30 that is fitted over the first flow passage body 20 in a compressed manner. The first flow passage body 20 is generally configured in the form of a sleeve member. The mandrel 10 is typically a preform and, in the embodiment shown in fig. 1, is configured in the form of a stepped shaft. The mandrel 10 can be connected at both ends, for example, to a bogie of a rail train, while the outer jacket 30 is connected to the positioning jib. An optional inner sleeve 15 may also be provided over the mandrel 10, as shown in FIG. 1. The two axial ends of the outer sleeve 30 are radially bent towards the mandrel 10, forming a flange 32 to facilitate sealing of the hydraulic bushing 100.

A first rubber body 40 is filled in the gap between the mandrel 10 and the first fluid 20. However, it is understood that in the case where the inner case 15 is provided, the first rubber body 40 may be filled between the inner case 15 and the first fluid passage 20. Two main liquid chambers 45 for containing hydraulic fluid are provided on the first rubber body 40, which are preferably configured to be diametrically opposed. That is, both the main liquid chambers 45 extend only partially in the circumferential direction and are opposed in the radial direction. Grooves are formed on the outer surface of the first flow channel body 20, which may be in the form of a spiral circumferential distribution. In the assembled state, the outer sleeve 30 is pressed against the first flow passage body 20, so that the groove in the first flow passage body 20 forms a first flow passage 42 for the hydraulic fluid to flow therein. Both ends of the first flow path 42 communicate with the two main liquid chambers 45, respectively. In addition, a liquid charging hole (not shown) for charging the hydraulic fluid is constructed on the outer sleeve 30 in communication with the first flow passage 42.

When the rail train runs in the straight-line section snake-shaped resisting operation stage, the wheels can bear high-frequency vibration, and when the rail train runs in a low-speed curve, the wheels can bear low-frequency vibration. Under the two working conditions, the movement of the wheel drives the mandrel 10 and the outer sleeve 30 to move relatively, so that the main liquid cavity at the front and the main liquid cavity at the rear can expand and contract respectively. Thus, hydraulic fluid can flow between the two main liquid chambers 45 through the first flow passage 42, and accordingly the rigidity of the hydraulic bushing 100 is adjusted, so that the train keeps stable operation. This varying stiffness is an important property of the hydraulic bushing 100.

the above-mentioned features and functions of the hydraulic bushing are known in the art, for example, see the applicant's chinese patent document CN108150536A, which is incorporated herein by reference.

According to the present invention, as shown in fig. 1, both ends of the first flow passage body 20 in the axial direction are closed by the seal assembly 50 so as to form a closed chamber for containing the hydraulic fluid, i.e., the main liquid chamber 45. The seal assembly 50 includes a rigid support ring 60 mounted on the mandrel 10. In the illustrated embodiment, the mandrel 10 is configured as a stepped shaft, and thus, the support ring 60 is preferably installed at the stepped structure of the mandrel 10 so as to form a good location and be more stably supported. A second rubber body 70 is vulcanized onto the support ring 60, and rigid gaskets 55, 56 (see fig. 2) are embedded in the second rubber body 70. In this way, the support ring 60 and the spacers 55, 56 are integrated by the second rubber body 70.

As shown more clearly in fig. 2, the vulcanized second rubber body 70 includes two axially spaced apart portions, an inner portion 72 adjacent the axial ends of the first runner body 20 and an outer portion 74 adjacent the axial ends of the outer sleeve 30. With this arrangement, the inner portion 72 of the second rubber body 70 forms a seal with the outer surface of the axial end portion of the first flow path body 20, while the outer portion 74 of the second rubber body 70 forms a seal with the axial end portion of the outer sheath 30 (specifically, the inner surface of the flange 32 formed at the axial end portion of the outer sheath 30). Thus, a sealed auxiliary fluid chamber 80 is formed between the inner portion 72 of the second rubber body 70, the outer portion 74 of the second rubber body 70, the support ring 60 and the outer sleeve 30, in which hydraulic fluid can be accommodated. Unlike the primary liquid chamber 45, however, the secondary liquid chamber 80 within each seal assembly 50 is configured to extend fully circumferentially, i.e., the secondary liquid chamber 80 extends 360 degrees circumferentially. Note that the auxiliary liquid chamber 80 is configured not to communicate with the main liquid chamber 45.

In the preferred embodiment as shown, support ring 60 also includes radially outwardly projecting tabs 62. The projection 62 is located axially between an inner portion 72 and an outer portion 74 of the second rubber body 70. In accordance with the present invention, the tabs 62 of the support ring 60 are located within the auxiliary fluid chamber 80 and extend all the way radially outward until sealing contact is made with the inner surface of the outer sleeve 30.

preferably, as shown in fig. 2, a third portion 76 of the second rubber body 70 is also provided on the projection 62 of the support ring 60. In this way, the support ring 60 is brought into sealing contact with the inner surface of the outer sleeve 30 by the third portion 76 of the second rubber body 70, thereby dividing the auxiliary liquid chamber 80 into two first sub-chambers 82 and second sub-chambers 84 axially adjacent to each other. As shown, the first subchamber 82 of the auxiliary fluid chamber 80 is axially outward, while the second subchamber 84 is axially inward.

According to the invention, a second flow channel 96, for example formed by a continuous groove, is provided on the inner surface of the support ring 60 (i.e. the surface in contact with the mandrel 10). The second flow passage 96 is configured such that one end (the axially outer end in the embodiment shown in fig. 2) is connected to the first subchamber 82 of the auxiliary chamber 80, and the other end (the axially inner end in the embodiment shown in fig. 2) is connected to the second subchamber 84 of the auxiliary chamber 80. In this way, the first sub-chamber 82 and the second sub-chamber 84 of the auxiliary liquid chamber 80, which are axially adjacent to each other, communicate with each other through the second flow passage 96. In this manner, hydraulic fluid is able to flow between first subchamber 82 and second subchamber 84 of auxiliary fluid chamber 80. Along with the flowing of the hydraulic fluid, the rigidity of the hydraulic bushing 100 in the axial direction can be changed in a larger range, the effect of changing the rigidity of the hydraulic bushing 100 in the axial direction is enhanced, and the purposes of low rigidity in the axial direction at low frequency and high rigidity in high frequency are achieved.

in addition, when the hydraulic bushing 100 is subjected to an axial sinusoidal excitation, the radial projections 62 of the support ring 60 will move axially back and forth, compressing the first and second subchambers 82, 84 on the left and right sides thereof. In this manner, an internal high pressure may be generated in one of the sub-chambers (e.g., first sub-chamber 82) and a corresponding internal low pressure may be generated in the other sub-chamber (e.g., second sub-chamber 84), such that hydraulic fluid may flow from the sub-chamber having the internal high pressure (e.g., first sub-chamber 82) into the sub-chamber having the internal low pressure (e.g., second sub-chamber 84). The hydraulic bushing 100 produces a variable stiffness in the axial direction due to the pressure differential existing between the two subchambers. This further enhances the axial stiffness-changing effect of the hydraulic bushing 100, achieving the purpose of low frequency low stiffness and high frequency high stiffness in the axial direction.

In addition, the third portion 76 of the second rubber body 70 may also provide a varying displacement in the radial direction, since the support ring 60 is in sealing contact with the inner surface of the outer sleeve 30 via the third portion 76 of the second rubber body 70. This also contributes to a degree to the rigidity variation in the radial direction of the hydraulic bushing 100.

In addition, hydraulic fluid can flow between the first sub-chamber 82 and the second sub-chamber 84 of the auxiliary fluid chamber 80 through the second flow passage 96 provided on the inner surface of the support ring 60, so that an additional auxiliary flow passage body does not need to be added in the auxiliary fluid chamber 80, and the space in the auxiliary fluid chamber 80 can be fully utilized. In this way, the resulting hydraulic bushing 100 has a more compact structure. In particular, when the product is subjected to an axial load, hydraulic fluid flows back and forth between first subchamber 82 and second subchamber 84 of auxiliary fluid chamber 80 through second flow passage 96 such that the hydraulic fluid produces a damping effect when passing through the inlet, outlet and flow paths within second flow passage 96. This is reflected in the on-way pressure loss and the local pressure loss caused by the hydraulic fluid flowing through the above-mentioned area. This further enhances the effect of the variable stiffness in the axial direction of the hydraulic bushing 100.

Without wishing to be bound by any theory, according to the present invention, the second flow passage 96 in the auxiliary fluid chamber 80 is primarily used to provide variable stiffness to the hydraulic bushing 100 in the axial direction, while the first flow passage 42 in the main fluid chamber 45 is primarily used to provide variable stiffness to the hydraulic bushing 100 in the radial direction. Thus, the geometric parameters of the cross-sectional area and length of the first and second flow passages 42, 96 may be designed according to the requirements for radial and axial stiffness of the hydraulic bushing 100.

According to the present invention, rigid spacers 55 and 56 are embedded within the outer portion 74 and inner portion 72 of the rubber body 70, respectively, to provide a degree of axial stiffness to the hydraulic bushing 100. In addition to the function of providing axial rigidity, the gasket 56 can also press the adjacent second rubber body 70, thereby sufficiently securing the sealing effect of the hydraulic fluid in the main liquid chamber 45 and the auxiliary liquid chamber 80. The insert 55 can then form a seal with the flange 32 of the metal casing 30 and the outer portion 74 of the second rubber body 70 located therebetween for the auxiliary liquid chamber 80. This further improves the sealing performance of the auxiliary liquid chamber 80.

According to the present invention, a hydraulic fluid filling channel 90 is also provided on the support ring 60. As shown in fig. 2 and 3, the hydraulic fluid feed channel 90 comprises a horizontal branch 92 opening onto an axial end of the support ring 60, and a vertical branch 94, which communicates at one end with the horizontal branch 92 and opens at the other end into the auxiliary liquid chamber 80. Thus, after the hydraulic bushing 100 is assembled, hydraulic fluid may be injected into the auxiliary fluid chamber 80 using the hydraulic fluid fill passage 90. After the injection is complete, the horizontal branch 92 of the hydraulic fluid injection passage 90 may be blocked, for example, using a plug (not shown). Alternatively, the hydraulic fluid feed channel 90 may also be sealed by driving steel balls into the inlet of the horizontal branch 92.

As shown in fig. 2, a vertical branch 94 of the hydraulic fluid charging passage 90 is provided to open into the axially outer first subchamber 82 of the auxiliary fluid chamber 80. Therefore, the structure can be simplified, the processing difficulty is reduced, and the cost is saved.

As shown in fig. 2, according to a preferred embodiment of the present invention, the end of second flow passage 96 connected to first subchamber 82 of auxiliary fluid chamber 80 is connected to first subchamber 82 of auxiliary fluid chamber 80 by means of vertical branch 94 of hydraulic fluid charging passage 90. Therefore, the structure is further simplified, the processing difficulty is reduced, and the cost is saved.

It should be noted that a seal assembly is required to be provided at both axial ends of the first fluid passage. Both seal assemblies may be seal assemblies 50 as described above, or only one of them may employ a seal assembly 50 as described above, while the other employs a conventional seal. Such a common seal need only provide a sealing effect to form a closed primary liquid chamber and is readily designed by a person skilled in the art.

While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present invention is not limited to the particular embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims (9)

1. A hydraulic bushing, comprising:

A mandrel;

A sleeve-shaped first fluid channel which is arranged on the mandrel in a sleeved manner, a first rubber body is filled in a gap between the mandrel and the first fluid channel, a first fluid channel for hydraulic fluid is formed on the outer surface of the first fluid channel, two main fluid cavities for containing hydraulic fluid are formed on the first rubber body in a radial direction and oppositely, and the two main fluid cavities are communicated with each other through the first fluid channel;

the outer sleeve is sleeved on the radial outer side of the first runner body in a pressing mode; and

A seal assembly disposed axially outwardly of at least one of said first flow passage bodies, said seal assembly defining with said outer casing an auxiliary fluid chamber for containing hydraulic fluid;

Wherein, the seal assembly comprises a support ring sleeved on the mandrel, the support ring comprises a radial protrusion part positioned in the auxiliary liquid cavity, the radial protrusion part is in sealing contact with the inner surface of the outer sleeve, so that the auxiliary liquid cavity is divided into a first sub-cavity positioned on the axial outer side and a second sub-cavity positioned on the axial inner side, and the support ring comprises a second flow passage used for communicating the first sub-cavity and the second sub-cavity of the auxiliary liquid cavity with each other.

2. The hydraulic bushing of claim 1 wherein said second flow passage is formed by a continuous groove formed in an inner surface of said support ring, wherein a first axially outer end of said groove is connected to said first subchamber and a second axially inner end is connected to said second subchamber.

3. A hydraulic bushing according to claim 2, characterized in that a hydraulic fluid filling channel is provided in the support ring for filling the auxiliary liquid chamber with hydraulic fluid.

4. A hydraulic bushing according to claim 3, characterized in that the hydraulic fluid filling channel comprises a horizontal branch leading to the axially outer end of the support ring, and a vertical branch leading to the first subcavity of the auxiliary liquid chamber.

5. A hydraulic bushing according to claim 4, wherein the first end of the groove is connected to the first subchamber by a vertical branch of the hydraulic fluid filling passage.

6. The hydraulic bushing of any one of claims 1 to 5, wherein the support ring further comprises a secondary rubber body vulcanized thereon such that the radial projections are in sealing contact with the inner surface of the outer sleeve through the secondary rubber body.

7. The hydraulic bushing of claim 6, wherein said auxiliary rubber body includes a first portion for making sealing contact with an axial end of said flow passage body, a second portion for making sealing contact with an axial end of said outer sleeve, and a third portion for making sealing contact with an inner surface of said outer sleeve, wherein said third portion is axially between said first and second portions.

8. A hydraulic bushing according to claim 7, characterized in that rigid shims are embedded in both the first and second portions of the auxiliary rubber body.

9. A hydraulic bushing according to any one of claims 1 to 5, wherein the cross-sectional area and length of the first flow passage are determined in accordance with the required radial dynamic stiffness of the hydraulic bushing, and the cross-sectional area and length of the second flow passage are determined in accordance with the required axial dynamic stiffness of the hydraulic bushing.