CN216975651U

CN216975651U - Auxiliary frame hydraulic bushing inner cage and hydraulic bushing comprising same

Info

Publication number: CN216975651U
Application number: CN202220906664.4U
Authority: CN
Inventors: 赵萍; 周晓光; 郭春杰
Original assignee: Boge Rubber and Plastics Zhuzhou Co Ltd
Current assignee: Boge Rubber and Plastics Zhuzhou Co Ltd
Priority date: 2022-04-19
Filing date: 2022-04-19
Publication date: 2022-07-15
Anticipated expiration: 2032-04-19

Abstract

The utility model provides an auxiliary frame hydraulic bushing inner cage and a hydraulic bushing comprising the same, wherein the auxiliary frame hydraulic bushing inner cage is integrally formed by adopting aluminum materials through a die-casting forming process, the auxiliary frame hydraulic bushing inner cage is of a cylindrical cage-shaped structure and comprises an annular upper section part, an annular lower section part and a plurality of sheet-shaped middle section parts, the upper section part and the lower section part correspond to each other up and down, the middle section parts are arranged between the upper section part and the lower section part at intervals, and a through hole is formed between every two adjacent middle section parts. The utility model does not affect the hollow, real and axial static rigidity and dynamic performance of the bushing. And the hydraulic bushing structure has the advantages of light weight, simple process, low manufacturing cost and the like, can obviously improve the performances of bearing, fatigue durability and the like, and meets the requirements of high bearing, high fatigue and low cost.

Description

Auxiliary frame hydraulic bushing inner cage and hydraulic bushing comprising same

Technical Field

The utility model relates to the field of automobile auxiliary frames, in particular to an auxiliary frame hydraulic bushing inner cage and a hydraulic bushing comprising the same.

Background

Fig. 1 is a schematic structural diagram of a hydraulic bushing assembly of a subframe for an automobile in the prior art.

As shown in fig. 1, the subframe hydraulic bushing assembly for an automobile generally comprises a rubber vulcanized body, an upper stopper 10, a lower stopper 20, a flow passage 30, an outer sleeve 40, etc., wherein the rubber vulcanized body comprises a metal inner frame, rubber 50, an inner cage 51, etc. At present, the stop material is generally made of plastics or cast aluminum, and the inner cage is mostly made of a stamping steel structure. The static rigidity difference of the radial X axis and the radial Y axis is large, the radial dynamic performance requirement of the hydraulic bushing is met, and the rubber molded surface is generally designed into a structure with two liquid cavities, so that the static rigidity requirement can be guaranteed, and the dynamic performance requirement can be met through the liquid cavity design. The radial direction is limited by utilizing the upper stop catch and the lower stop catch, and the axial stroke control is carried out by utilizing the design of the upper rubber bulge and the lower rubber bulge. The specific method is that after the rubber vulcanized body is vulcanized, a flow channel is assembled, the liquid is encapsulated while the outer sleeve is assembled, and finally the upper stop catch and the lower stop catch are assembled, and the cover plate 60 is installed.

However, the hydraulic bush assembly of the conventional automotive subframe has the following problems:

firstly, an inner cage of the rubber vulcanized body is made of stamping steel, and the product is heavy in mass;

secondly, series of dies are needed for stamping the inner cage, so that the cost is very high;

few suppliers with the production capacity of the punching inner cage are provided, the localization degree is very low, most of the suppliers depend on imports, the price is high, and the lead cycle is long;

fourthly, the domestic punching inner cage has low qualification rate and is difficult to completely meet the requirements of drawings;

fifthly, the stamping inner cage is made of steel, and a phosphating process is generally needed in the pretreatment of vulcanization;

sixthly, integral anticorrosion treatment is carried out on the part with the part exposed;

seventhly, the bearing is low;

eighthly, the fatigue resistance performance is poor, and the dynamic performance is reduced due to the fact that the bushing is prone to cracking, liquid leakage and other quality problems.

In view of this, the utility model people have designed a sub vehicle frame hydraulic pressure bush inner cage and including its hydraulic pressure bush to overcome above-mentioned technical problem.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects that in the prior art, an auxiliary frame hydraulic bushing assembly for an automobile is heavy in weight, high in cost, easy to cause problems in quality and the like, and provides an auxiliary frame hydraulic bushing inner cage and a hydraulic bushing comprising the same.

The utility model solves the technical problems through the following technical scheme:

the utility model provides a cage in sub vehicle frame hydraulic liner, its characterized in that, cage adopts the aluminum product to pass through die-casting forming process integrated into one piece in the sub vehicle frame hydraulic liner, cage in the sub vehicle frame hydraulic liner is cylindrical cage-shaped structure, including ring shape upper segment portion, ring shape lower segment portion and a plurality of flaky midrange portion, the upper segment portion with hypomere portion corresponds from top to bottom, the mutual spaced arrangement of midrange portion is in the upper segment portion with between the lower segment portion, adjacent two form the through-hole between the midrange portion.

According to one embodiment of the utility model, at least one circle of clamping grooves is arranged on the outer peripheral surface of the upper section part.

According to one embodiment of the utility model, the bottom of the outer circumferential surface of the lower section is provided with an outwardly extending flange, which surrounds the outer circumferential surface of the lower section.

According to one embodiment of the utility model, the outer edge of the flange is provided with at least one notch.

The utility model also provides an auxiliary frame hydraulic bushing which is characterized by comprising the auxiliary frame hydraulic bushing inner cage, a rubber body, an inner core, an outer sleeve, an upper stop, a lower stop and a flow passage, wherein the rubber body is arranged in the auxiliary frame hydraulic bushing inner cage, and the inner core is arranged in the rubber body and is vulcanized to form a vulcanized body in an integrated structure;

the outer sleeve is sleeved outside the vulcanizing body, the upper stop is installed at the upper end part of the inner core, the lower stop is installed at the lower end part of the inner core, and the flow channel is installed on the outer wall surface of the outer sleeve.

According to one embodiment of the utility model, the upper end surface of the inner core is provided with at least one water leakage groove.

According to one embodiment of the utility model, the subframe hydraulic bushing further comprises a lower cover plate, the inner core is provided with an inner hole, and the lower cover plate is fixed to the bottom of the inner core through a connecting piece penetrating through the inner hole.

According to one embodiment of the utility model, the upper stop and the lower stop are injection molded from plastic.

According to an embodiment of the present invention, the upper stopper includes a first ring, a first stopper portion and a second stopper portion, and the first stopper portion and the second stopper portion are oppositely disposed on the first ring;

the height of the first stopping portion is larger than that of the second stopping portion, the first stopping portion is located in the radial hollow direction of the subframe hydraulic bushing, and the second stopping portion is located in the radial solid direction of the subframe hydraulic bushing.

According to an embodiment of the present invention, the lower stopper includes a second ring, a third stopper and a fourth stopper, and the third stopper and the fourth stopper are oppositely disposed on the second ring;

the third stopping portion is higher than the fourth stopping portion, the third stopping portion is located in the radial hollow direction of the subframe hydraulic bushing, and the fourth stopping portion is located in the radial solid direction of the subframe hydraulic bushing.

According to an embodiment of the utility model, the upper outer wall surface of the inner core is provided with an upper step extending outwards, the lower outer wall surface of the inner core is provided with a lower step extending outwards, the upper step is used for limiting the upper stop from moving downwards, and the lower step is used for limiting the lower stop from moving upwards.

According to one embodiment of the utility model, the upper end part of the outer sleeve is provided with a flange which is turned inwards, the flange is fastened with the rubber body, and the upper outer profile of the inner core corresponding to the flange is provided with a chamfer.

According to one embodiment of the utility model, the chamfer is in the range of 30 ° to 45 °.

The positive progress effects of the utility model are as follows:

according to the auxiliary frame hydraulic bushing inner cage and the hydraulic bushing comprising the same, an aluminum inner cage structure is adopted to replace the existing stamping steel inner cage of the hydraulic auxiliary frame bushing and other products, and the hollow, real-direction and axial static rigidity, fatigue durability and other performances of the bushing are not affected. The auxiliary frame hydraulic bushing inner cage structure has the advantages of light weight, simple process, low manufacturing cost and the like, and can realize high bearing.

The hydraulic bushing structure does not affect the hollow, real and axial static rigidity and dynamic performance of the bushing. The hydraulic bushing structure has the advantages of light weight, simple process, low manufacturing cost and the like, can obviously improve the performances of bearing, fatigue durability and the like, and meets the requirements of high bearing, high fatigue and low cost.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description of the embodiments with reference to the accompanying drawings in which like reference numerals denote like features throughout the several views, wherein: ground

FIG. 2 is a schematic structural view of an inner cage of the subframe hydraulic bushing of the present invention.

FIG. 3 is a longitudinal cross-sectional view of the inner cage of the subframe hydraulic bushing of the present invention.

FIG. 4 is a schematic view of the porosity detection area of the inner cage of the subframe hydraulic bushing of the present invention.

FIG. 5 is a schematic view of the structure of the subframe hydraulic bushing of the present invention.

FIG. 6 is a schematic view of the sub-frame hydraulic bushing of the present invention assembled.

FIG. 7 is a schematic view of the installation of the upper cushion block of the rubber body in the subframe hydraulic bushing of the present invention.

FIG. 8 is a schematic view of the installation of the lower cushion block of the rubber body in the subframe hydraulic bushing of the present invention.

FIG. 9 is a schematic view of the upper stop of the subframe hydraulic bushing of the present invention.

FIG. 10 is a schematic view of the structure of the lower stop of the subframe hydraulic bushing of the present invention.

FIG. 11 is a schematic view of the installation of the upper and lower stops on the subframe hydraulic bushing of the present invention.

Fig. 12 is a perspective view of the inner core of the subframe hydraulic bushing of the present invention.

FIG. 13 is a side view of the inner core of the subframe hydraulic bushing of the present invention.

FIG. 14 is a schematic view of the upper and lower stops and the inner core installed in the subframe hydraulic bushing of the present invention.

FIG. 15 is a schematic view of the installation of the hydraulic seal ring in the subframe hydraulic bushing of the present invention.

FIG. 16 is a cross-sectional view of a portion of the subframe hydraulic bushing of the present invention with a hydraulic seal ring installed.

FIG. 17 is a schematic view of the mounting of the outer cover and rubber body in the subframe hydraulic bushing of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

Further, although the terms used in the present invention are selected from publicly known and used terms, some of the terms mentioned in the description of the present invention may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein.

Furthermore, it is required that the present invention is understood, not simply by the actual terms used but by the meaning of each term lying within.

As shown in fig. 2 to 4, the utility model discloses an inner cage 100 of a hydraulic bushing of a subframe, which is integrally formed by an aluminum material through a die-casting molding process, and is in a cylindrical cage-shaped structure and comprises an annular upper section 110, an annular lower section 120 and a plurality of sheet-shaped middle sections 130, wherein the upper section 110 and the lower section 120 correspond to each other up and down, the middle sections 130 are arranged between the upper section 110 and the lower section 120 at intervals, and a through hole a is formed between two adjacent middle sections 130.

Conventional subframe hydraulic bushing inner cages typically employ stamped steel hydraulic subframe bushing inner cages. The inner cage structure designed by the utility model adopts aluminum materials, the aluminum materials can preferably adopt common aluminum casting materials 43400/44300, and the process is easy to realize automatic production. Moreover, the cast aluminum inner cage does not need pre-phosphating treatment and corrosion prevention.

The inner cage made of aluminum material is formed by die casting, aluminum liquid is pressed into a precise metal die cavity at high speed by high pressure, and the aluminum liquid is cooled and solidified under the action of pressure to form a casting. The process is simple and controllable, only one-step molding of the mold is needed, the manufacturing cost is low, and the process control can ensure good mechanical properties. Meanwhile, the appearance design needs to comprehensively consider various factors such as the bearing requirement of the inner cage, the rigidity performance requirement of the vulcanized body, light weight, forming process and the like, and the requirement on designers is higher.

Preferably, at least one ring of locking grooves 111 is arranged on the outer circumferential surface of the upper section 110. The bottom of the outer periphery of the lower section 120 is provided with an outwardly extending flange 121, and the flange 121 surrounds the outer periphery of the lower section 120. The flange 121 may also be formed with at least one notch 122 in its outer edge.

The structural design of the slots 111 in the outer face of the upper end 110 must take into account porosity. Porosity is one of the important indicators for quality of castings, and if the porosity is too large or too large, it will affect the mechanical properties of the metal parts. The lower the porosity, i.e. the denser the material of the part, the stronger the part is, which is the key carrier, the porosity requirement being at most 5%.

As shown in fig. 4, the porosity detection area, the simulation technology of the die-casting process, and the simulation of the casting filling process (flow field) can predict the air entrainment in the shooting pot, the pouring gate and the cavity. The numerical simulation of the casting and mold filling process can help technicians to effectively predict the pressure, the position and the occurrence time of various types of rolling gas which may appear in the casting at the casting process stage, so that the casting process design is optimized, the quality of the casting is ensured, the trial production period is shortened, and the production cost is reduced. The design of the clamping groove 111 comprehensively considers the simulation results of the strength of the inner cage and the die-casting numerical value.

As shown in fig. 5 and 6, the present invention further provides a subframe hydraulic bushing, which comprises the subframe hydraulic bushing inner cage 100, a rubber body 200, an inner core 300, an outer sleeve 400, an upper stopper 500, a lower stopper 600 and a flow passage 700 as described above, wherein the rubber body 200 is mounted in the subframe hydraulic bushing inner cage 100, the inner core 300 is mounted in the rubber body 200, and a vulcanized body B of an integrated structure is vulcanized. The outer sleeve 400 is sleeved outside the vulcanizing body B, the upper stop 500 is installed at the upper end part of the inner core 300, the lower stop 600 is installed at the lower end part of the inner core 300, and the flow channel 700 is installed on the outer wall surface of the outer sleeve 400.

As shown in fig. 7, the thickness of the upper end surface of the inner cage 100 of the subframe hydraulic bushing needs to be designed in consideration of the thickness of the upper rubber buffer block, and a certain space needs to be reserved, wherein the space requirement is determined according to the thickness required by the rigidity design of the buffer block. When the sub frame hydraulic bushing is pressed into the sub frame, the upper cushion block 210 of the rubber body 200 contacts the vehicle body, and the upper cushion block 210 is deformed by the pressing of the vehicle body during the up and down movement of the sub frame hydraulic bushing along with the sub frame 800, thereby absorbing vibration and energy.

Meanwhile, the rubber body 200 must have a certain rigidity to ensure a rigidity curve meeting the requirements of customers, and the rigidity is related to the thickness of the rubber body 200. The thickness is too small, the rigidity of the rubber body 200 is small, and the vehicle body easily collides with the outer cover 400 and the sub frame 800, thereby exerting an influence. The thickness is too large, and the rigidity of the rubber body 200 is too large, which affects the comfort of the vehicle body.

As shown in fig. 8, the flange 121 provided at the lower section of the subframe hydraulic bushing inner cage 100 is designed in consideration of the design of the lower cushion block 220 of the rubber body 200, and the design principle of the lower cushion block 220 is the same as that of the upper cushion block 210.

Here, the flange 121 provided at the lower section of the subframe hydraulic bushing inner cage 100 functions as: firstly, when the auxiliary frame hydraulic bushing is pressed into the auxiliary frame 800, the acting point of the tool must be on the flange 121; secondly, a certain contact area must be ensured between the flange 121 and the subframe 800, so as to ensure that the subframe hydraulic bushing is accurately installed at the corresponding position of the subframe 800.

As shown in fig. 9 to 11, the upper stopper 500 and the lower stopper 600 are preferably injection molded using plastic. Wherein the upper stopper 500 preferably includes a first ring 510, a first stopper 520 and a second stopper 530, the first stopper 520 and the second stopper 530 being oppositely disposed on the first ring 510. The height of the first stopping portion 520 is greater than that of the second stopping portion 530, the first stopping portion 520 is located in a radial hollow direction C of the subframe hydraulic bushing, and the second stopping portion 530 is located in a radial solid direction D of the subframe hydraulic bushing (as shown in fig. 2 and 11).

The lower stopper 600 preferably includes a second ring 610, a third stopper 620 and a fourth stopper 630, and the third stopper 620 and the fourth stopper 630 are oppositely disposed on the second ring 610. The height of the third stopping portion 620 is greater than that of the fourth stopping portion 630, the third stopping portion 620 is located in the radial hollow direction C of the subframe hydraulic bushing, and the fourth stopping portion 630 is located in the radial solid direction D of the subframe hydraulic bushing (as shown in fig. 2 and 11).

The upper stop 500 and the lower stop 600 function as: the linear stroke of the bushing in the radial hollow direction is ensured, and the stroke parameter is a very important performance index of the bushing. The distance between the radial hollow part and the rubber body 200 of the upper stop 500 and the lower stop 600 shown in fig. 11 is the stroke, and the upper part and the lower part are consistent. When the auxiliary frame hydraulic bushing moves radially, the upper stop 500 and the lower stop 600 contact the rubber body 200, a large load (generally provided by a main machine length) exists in the contact process, and in order to ensure that the upper stop 500 and the lower stop 600 meet the bearing requirements, the height design of the stops in the radial hollow direction needs to be determined after strength checking.

As shown in fig. 11, the heights of the upper stopper 500 and the lower stopper 600 are different in the circumferential direction, and the height in the radial solid direction D is significantly smaller than the height in the hollow direction C (i.e., the height of the first stopper 520 is greater than the height of the second stopper 530, and the height of the third stopper 620 is greater than the height of the fourth stopper 630), and the minimum value of 3mm is ensured by the design of the void in the radial solid direction.

As shown in fig. 12 and 13, preferably, at least one water leakage groove 310 is formed on the upper end surface of the inner core 300. The sub-frame hydraulic bushing further includes a lower cover plate 900, the inner core 300 is provided with an inner hole, and the lower cover plate 900 is fixed to the bottom of the inner core 300 by penetrating the inner hole through a connecting member (e.g., a bolt) to connect the lower cover plate 900 and the vehicle body 70. The depth and shape of the water leakage groove 310 are not strictly limited, but cannot affect the strength of the inner core 300 and obviously reduce the stressed area, and the strength of the inner core 300 must be checked and evaluated during design.

Here, the provision of the water leakage groove 310 may lead out water accumulated inside the bushing core, reduce corrosion of the water accumulated on the connection member (e.g., bolt), and thus improve the life of the connection member (e.g., bolt).

Further, the upper outer wall surface of the inner core 300 is provided with an upper step 320 extending outward, the lower outer wall surface of the inner core 300 is provided with a lower step 330 extending outward, the upper step 320 is used for limiting the downward movement of the upper stopper 500, and the lower step 330 is used for limiting the upward movement of the lower stopper 600.

As shown in fig. 14, during the up-and-down movement of the subframe hydraulic bushing, the rubber body 200 moves up and down together, and the upper stop 500 and the lower stop 600 cannot move up and down. As shown in fig. 7, the upper portion of the upper stopper 500 is in direct contact with the vehicle body 70 and does not move upward, so that the downward direction must be designed to be secured. Similarly, the lower cover 900 and the lower stop 600 in fig. 8 are in direct contact and do not move downward, so the upward direction must be designed to be ensured.

The design of the upper step 320 and the lower step 330 on the inner core 300 respectively ensures that the upper stopper 500 does not move downwards and the lower stopper 600 does not move upwards. When bearing large impact force, guarantee that backstop 500 and backstop 600 can not be at the axial contact rubber liquid chamber wall, the fracture and the weeping problem that leads to by the fracture has significantly reduced to show improvement bush life-span.

As shown in fig. 15 and 16, the structural design of the engaging groove 111 on the outer surface of the upper section 110 of the subframe hydraulic bushing inner cage 100 must also take into consideration the hydraulic seal. As the subframe hydraulic bushing moves, the volume of fluid chamber 112 may become larger or smaller, thereby causing a change in pressure within fluid chamber 112.

When the pressure is increased, the liquid may flow out along the minute gap between the rubber body 200 and the outer cover 400, and a leakage failure may occur. Therefore, a liquid seal ring 113 as shown in fig. 15 and 16 is usually designed on the vulcanized body B to ensure that the liquid does not flow out. The position of the liquid seal ring 113 cannot be arranged in the recess of the clamping groove 111, so the design of the clamping groove 111 must ensure the position of the liquid seal ring 113.

As shown in fig. 17, it is more preferable that the upper end of the outer sheath 400 is provided with a flange 410 folded inward, the flange 410 fastens the rubber body 200, and the upper end of the core 300 corresponding to the flange 410 is provided with a chamfer a. Here, the range of the chamfer a is preferably 30 ° to 45 °. This structural design may prevent relative sliding of outer cover 400.

Due to the structural design of the outer surface of the upper section 110 of the subframe hydraulic bushing inner cage 100, the bushing pressing force must also be ensured. When the subframe hydraulic bushing is pressed out from the subframe 800, a general host factory requires a pressing force of more than 10kN, and the pressed subframe hydraulic bushing does not leak liquid. With such a large pressing force, the outer jacket 400 may slide on the surface of the rubber body 200, which may cause leakage.

In conclusion, the auxiliary frame hydraulic bushing inner cage and the hydraulic bushing comprising the same adopt an aluminum inner cage structure to replace the stamping steel inner cage of the existing hydraulic auxiliary frame bushing and other products, and the hollow, real, axial static rigidity, fatigue durability and other performances of the bushing are not influenced. The auxiliary frame hydraulic bushing inner cage structure has the advantages of light weight, simple process, low manufacturing cost and the like, and can realize high bearing.

The hydraulic bushing structure does not affect the hollow, real and axial static rigidity and dynamic performance of the bushing. And the hydraulic bushing structure has the advantages of light weight, simple process, low manufacturing cost and the like, can obviously improve the performances of bearing, fatigue durability and the like, and meets the requirements of high bearing, high fatigue and low cost.

While specific embodiments of the utility model have been described above, it will be appreciated by those skilled in the art that these are by way of example only, and that the scope of the utility model is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the utility model, and these changes and modifications are within the scope of the utility model.

Claims

1. The utility model provides a cage in sub vehicle frame hydraulic liner, a serial communication port, cage in the sub vehicle frame hydraulic liner adopts the aluminum product to pass through die-casting forming process integrated into one piece, the cage is cylindrical cage-like structure in the sub vehicle frame hydraulic liner, including ring shape upper segment portion, ring shape lower segment portion and a plurality of flaky midrange portion, the upper segment portion with hypomere portion corresponds from top to bottom, the mutual spaced arrangement of midrange portion is in the upper segment portion with between the lower segment portion, adjacent two form the through-hole between the midrange portion.

2. The subframe hydraulic bushing inner cage of claim 1, wherein said upper section has at least one ring of notches formed in an outer peripheral surface thereof.

3. The subframe hydraulic bushing inner cage of claim 1 wherein said lower section portion is provided at a bottom portion of an outer peripheral surface thereof with an outwardly extending flange, said flange surrounding said lower section portion outer peripheral surface.

4. The subframe hydraulic bushing inner cage of claim 3, wherein said flange has at least one notch formed in an outer edge thereof.

5. A subframe hydraulic bushing, characterized in that the subframe hydraulic bushing comprises the subframe hydraulic bushing inner cage according to any one of claims 1 to 4, a rubber body, an inner core, an outer sleeve, an upper stopper, a lower stopper and a flow passage, wherein the rubber body is mounted in the subframe hydraulic bushing inner cage, the inner core is mounted in the rubber body and vulcanized to form a vulcanized body of an integrated structure;

6. The subframe hydraulic bushing of claim 5 wherein said inner core has at least one water drain channel formed in an upper end surface thereof.

7. The subframe hydraulic bushing of claim 6 further comprising a lower cover plate, wherein the inner core is provided with an internal bore, and wherein the lower cover plate is secured to the bottom of the inner core by a connector extending through the internal bore.

8. The subframe hydraulic bushing of claim 5 wherein said upper stop and said lower stop are injection molded from plastic.

9. The subframe hydraulic bushing of claim 8 wherein said upper stop comprises a first ring, a first stop, and a second stop, said first stop and said second stop being oppositely disposed on said first ring;

10. The subframe hydraulic bushing of claim 8 wherein said lower stop comprises a second ring, a third stop, and a fourth stop, said third stop and said fourth stop being oppositely disposed on said second ring;

11. The subframe hydraulic bushing of claim 8 wherein said upper outer wall surface of said inner core is provided with an outwardly extending upper step and said lower outer wall surface of said inner core is provided with an outwardly extending lower step, said upper step limiting downward play of said upper stop and said lower step limiting upward play of said lower stop.

12. The subframe hydraulic bushing of claim 5 wherein said outer sleeve has an inwardly turned flange at an upper end thereof, said flange fastens said rubber body, and said flange has a chamfer on an upper outer profile of said inner core corresponding to said flange.

13. The subframe hydraulic bushing of claim 12 wherein said chamfer is in the range of 30 ° to 45 °.