Bushing-type hydraulic mount

Abstract

The present invention relates to a bush-type hydraulic mount for mounting an electric machine module in an electric vehicle. The bush-type hydraulic mount includes an inner tube, a middle tube disposed coaxially with the inner tube, and a main rubber vulcanized between the inner tube and the middle tube. An outer tube surrounds the middle tube. The main rubber includes a front fluid chamber, a back fluid chamber, and a bridge portion, the front fluid chamber being recessed from a surface of the main rubber; the back fluid chamber being adjacent to the front fluid chamber and recessed from the surface of the main rubber; the bridge portion separating the front fluid chamber and the back fluid chamber such that fluid flows between the front fluid chamber and the back fluid chamber and the bridge portion is deformable by an external force.

Description

Technical Field

[0001] This invention relates to an automotive mount, and more specifically, to a bush-type hydraulic mount for mounting a motor module in an electric vehicle. Background Technology

[0002] Recently, research on electric vehicles (which are environmentally friendly vehicles) has been very active. Electric vehicles are driven by electric motors instead of the engines used in the past, and are powered by rechargeable batteries instead of fossil fuels. Because the low-frequency vibrations generated in electric vehicles are minimal, the motors are typically mounted in a center-supported manner. Furthermore, since the motor module, which includes the motor and power electronics, is lighter than existing engines, bushing-type rubber mounts are used instead of hydraulic mounts.

[0003] However, due to shape limitations, the axial characteristics of bushing-type rubber suspensions are very low. Therefore, the problem is that residual vibration increases with increasing axial behavior when passing through the plastic protrusion. To address this, in some cases an additional mounting point (e.g., an axial torque rod) is added, but this is disadvantageous in terms of packaging layout and assembly convenience, and increases manufacturing cost and weight. Summary of the Invention

[0004] The present invention aims to solve the above-mentioned problems, and the object of the present invention is to provide a bushing-type hydraulic mount that can solve the problem of residual vibration in electric vehicles by having improved axial characteristics.

[0005] Another objective is to provide a bushing-type hydraulic mount that minimizes increases in manufacturing cost and weight. The objectives of this invention are not limited to those described above, and other objectives not mentioned herein will be apparent to those skilled in the art (hereinafter referred to as "those skilled in the art") from the following description.

[0006] The features of the present invention, which are used to achieve the objectives of the present invention and to perform the characteristic functions of the present invention, are described below.

[0007] The bushing-type hydraulic suspension according to the present invention may include: an inner tube, a middle tube coaxially arranged with the inner tube, a main rubber vulcanized between the inner tube and the middle tube, and an outer tube surrounding the middle tube, wherein the main rubber includes: a front fluid chamber, a rear fluid chamber, and a bridging portion, the front fluid chamber being recessed from the surface of the main rubber; the rear fluid chamber being adjacent to the front fluid chamber and recessed from the surface of the main rubber; the bridging portion separating the front fluid chamber and the rear fluid chamber, such that fluid flows between the front fluid chamber and the rear fluid chamber, and the bridging portion being deformable by external force.

[0008] The method for assembling a bushing-type hydraulic suspension according to the present invention may include: providing a middle tube having an axial opening and an inner tube disposed radially inward; vulcanizing a main rubber between the inner tube and the middle tube, the main rubber having a front fluid chamber, a rear fluid chamber and a bridging portion, the front fluid chamber being recessed from the surface of the main rubber; the rear fluid chamber being adjacent to the front fluid chamber and recessed from the surface of the main rubber; the bridging portion being formed between the front fluid chamber and the rear fluid chamber, protruding radially outward beyond the middle tube and being deformable by external force, wherein a first side serving as one side of the bridging portion is longer than a second side serving as the opposite side of the first side; and assembling an outer tube from the second side to surround the outer side of the middle tube.

[0009] According to the present invention, a bushing-type hydraulic mount is provided, which can address the problem of residual vibration in electric vehicles by having improved axial characteristics. Furthermore, according to the present invention, a bushing-type hydraulic mount is provided that minimizes increases in manufacturing cost and weight.

[0010] The effects of the present invention are not limited to those described above, and those skilled in the art will clearly recognize other effects from the following description. Attached Figure Description

[0011] The above-mentioned and other objects, features and advantages of the invention will become clearer from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0012] Figure 1A The motor module mounting system for an electric vehicle is shown.

[0013] Figure 1B The bushing-type rubber suspension of the related technology is shown;

[0014] Figure 2 It is along Figure 1B A cross-sectional view of line A-A';

[0015] Figure 3A This is a perspective view showing one side of the bushing-type hydraulic suspension according to the present invention;

[0016] Figure 3B This shows the view from the bottom. Figure 3A A three-dimensional view of the other side of the bushing-type hydraulic suspension;

[0017] Figure 4A This is a cross-sectional view of the bushing-type hydraulic suspension according to the present invention;

[0018] Figure 4B A bushing-type hydraulic suspension according to the present invention is shown;

[0019] Figure 5 This is a side view of the bushing-type hydraulic suspension according to the present invention with the outer tube removed;

[0020] Figures 6A to 6H The assembly process of the bushing-type hydraulic suspension according to the present invention is shown;

[0021] Figure 7A and Figure 7B The behavioral characteristics of the embodiments of the present invention and the comparative examples were compared. Detailed Implementation

[0022] In the following, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings. The specific structures or functions described in the embodiments of the invention are for illustrative purposes only. Embodiments of the invention can be implemented in various forms, and it should be understood that embodiments of the invention should not be construed as limited to those described in this specification, but rather include various modified, equivalent, or alternative embodiments contained within the spirit and scope of the invention.

[0023] It should be understood that although the terms "first," "second," etc., used below are used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the teachings of the invention, the first element described below may be referred to as the second element. Similarly, the second element may also be referred to as the first element.

[0024] It should be understood that when an element is referred to as "joined" or "connected" to another element, an element may be directly joined or connected to the other element, or there may be an intermediate element between the two elements. Conversely, it should be understood that when an element is referred to as "directly joined" or "directly connected" to another element, there is no intermediate element. Other expressions used to explain the relationship between elements, such as "between," "directly between," "adjacent," or "directly adjacent," should be interpreted in the same manner.

[0025] Throughout this specification, the same reference numerals denote the same components. Furthermore, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” as used herein are intended to include the plural forms as well. It will be further understood that when terms such as “comprising,” “including,” “having,” etc., are used in this specification, the presence of said components, steps, operations, and / or elements is specified, and the presence or addition of one or more other components, steps, operations, and / or elements is not excluded.

[0026] It should be understood that the term “vehicle” or “of a vehicle” or other similar terms used herein generally include motor vehicles, such as passenger vehicles including sport utility vehicles (SUVs), buses, trucks, and various commercial vehicles, including various boats, ships, aircraft, etc., and also include hybrid vehicles, electric vehicles, internal combustion engine vehicles, hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-fossil energy sources).

[0027] While the exemplary embodiments are described as using multiple units to perform the exemplary process, it should be understood that the exemplary process may also be performed by one or more modules. Furthermore, it should be understood that the term controller / control unit refers to a hardware device that includes a memory and a processor and is specifically programmed to perform the processes described herein. The memory is configured to store modules, and the processor is specifically configured to execute said modules to perform one or more processes further described below.

[0028] The present invention will now be described in detail with reference to the accompanying drawings.

[0029] refer to Figure 1A In electric vehicles, the motor module is mounted via bushing-type rubber mounts 500 in the front-rear direction and left and right mounts 600a and 600b. Figure 1A In this context, "FW" indicates the forward direction of the vehicle.

[0030] On electric vehicle platforms, the axial characteristics of bushing-type rubber mounts are lower than their lateral or vertical characteristics. For example, refer to... Figure 1B It was found that the characteristic X1 of the bushing rubber suspension in the axial direction is 20 kgf / mm, the characteristic Y1 in the lateral direction is 65 kgf / mm, and the characteristic Z1 in the vertical direction is 65 kgf / mm.

[0031] Therefore, the axial direction of the front suspension 500 is aligned with the X direction, which is the longitudinal direction, to increase lateral characteristics. In this case, due to the low axial characteristics of the suspension 500, residual vibration is large. Specifically, it is necessary to improve the axial characteristics, but it is impossible to improve the axial characteristics due to the characteristics caused by the shape of the bushing-type rubber suspension.

[0032] This invention provides a bushing-type hydraulic mount 1 that solves this problem. The bushing-type hydraulic mount 1 according to the invention is a bushing-type engine mount specifically designed for electric vehicles, which has axial damping and contains a sealed fluid. Bushing-type mounts have high vertical and lateral characteristics, but are limited in increasing axial characteristics. This invention proposes a bushing-type hydraulic mount with axial damping to minimize axial behavior, thereby solving this problem.

[0033] Figure 2 This is a cross-sectional view of a bushing-type rubber suspension 500 according to related technology. The bushing-type rubber suspension 500 is formed by vulcanizing rubber 520 between an inner tube 510 and an outer tube 530 arranged coaxially. The present invention provides a bushing-type hydraulic suspension 1 with improved axial characteristics by adding a few parts compared to the bushing-type rubber suspension 500.

[0034] like Figure 3A As shown, the bushing-type hydraulic suspension 1 according to the present invention may include an inner tube 20, a main rubber 40, a middle tube 60, and an outer tube 80. The inner tube 20, the middle tube 60, and the outer tube 80 are arranged coaxially, and the main rubber 40 is vulcanized between the inner tube 20 and the middle tube 60.

[0035] According to the present invention, the bushing-type hydraulic suspension 1 vertically has two sets of fluid chambers and channels, thereby maximizing the damping value. Accordingly, according to an embodiment of the present invention, the main rubber 40 may include a front fluid chamber 140, a rear fluid chamber 240, a first fixing portion 340, a bridging portion 440, a second fixing portion 540, a channel 640, and a guide portion 740. That is, each of the front fluid chamber 140, the rear fluid chamber 240, the first fixing portion 340, the bridging portion 440, the second fixing portion 540, the channel 640, and the guide portion 740 may be formed symmetrically up and down relative to the axial direction of the bushing-type hydraulic suspension 1.

[0036] The front fluid chamber 140 and the rear fluid chamber 240 are separated by a bridging portion 440, and fluid can flow between them. The front fluid chamber 140 is disposed between the first fixing portion 340 and the bridging portion 440 along the axial direction of the bushing-type hydraulic suspension 1. The rear fluid chamber 240 is disposed between the bridging portion 440 and the second fixing portion 540 along the axial direction of the bushing-type hydraulic suspension 1. The first fixing portion 340 and the second fixing portion 540 are fixed to the central tube 60. As will be described below, the bridging portion 440 is movable relative to the central tube 60.

[0037] Fluid is retained in the front fluid chamber 140 and the rear fluid chamber 240 and is recessed inward from the surface of the main rubber 40 along the radial direction of the bushing-type hydraulic suspension 1.

[0038] A bridging portion 440 is disposed between the front fluid chamber 140 and the rear fluid chamber 240. The bridging portion 440 is integrally formed with the main rubber 40 and can be deformed by external force. According to an embodiment of the invention, the bridging portion 440 has a front portion 442, a contact portion 444, and a rear portion 446 (see...). Figure 4A ).

[0039] The front part 442 is in direct contact with the front fluid chamber 140. The rear part 446 is in direct contact with the rear fluid chamber 240. The contact part 444 is in contact with the outer tube 80, and the contact position and area on the outer tube 80 can be changed by external force.

[0040] The thickness of the bridging portion 440 gradually decreases outward along the radial direction of the bushing-type hydraulic suspension 1. The bridging portion 440 tapers gradually to be biased in one direction, thus its thickness gradually decreases radially outward. Therefore, according to an embodiment of the invention, the front portion 442 is shorter than the rear portion 446. Due to this shape, the bridging portion 440 can deform or bend in only one direction, thereby improving durability and ease of assembly and reducing noise.

[0041] like Figure 5 As shown, the bridging portion 440 extends radially outwards further than the first fixing portion 340 and the second fixing portion 540. Correspondingly, the bridging portion 440 protrudes radially outwards by a length d beyond the central tube 60. According to an embodiment of the invention, the bridging portion 440 protrudes radially outwards by approximately 3 to 5 mm beyond the central tube 60.

[0042] The front fluid chamber 140 and the rear fluid chamber 240 are connected by a channel 640, allowing fluid to flow between them. When the front fluid chamber 140 or the rear fluid chamber 240 expands or contracts by an external force, the fluid in the front fluid chamber 140 and the fluid in the rear fluid chamber 240 can move through the channel 640 to the other of the two fluid chambers.

[0043] Similar to the front fluid chamber 140 and the rear fluid chamber 240, the channel 640 is recessed from the surface of the main rubber 40. According to an embodiment of the invention, the recess depth of the channel 640 is less than the recess depth of the front fluid chamber 140 and the rear fluid chamber 240.

[0044] The cross-sectional area of ​​channel 640 can be increased or decreased by the guide portion 740. The size of the inlets of the front fluid chamber 140 and the rear fluid chamber 240 can be adjusted by adjusting the size of the guide portion 740. The guide portion 740 can be provided by forming a channel 640 connecting the front fluid chamber 140 and the rear fluid chamber 240 to each other. In other words, the guide portion 740 has the same height as the surface of the first fixing portion 340 and the second fixing portion 540 or the main rubber 40, but is higher than the channel 640. According to the present invention, the length and / or area of ​​the channel 640 formed in the main rubber 40 can be adjusted, thereby adjusting the damping frequency, etc.

[0045] refer to Figure 3B According to an embodiment of the invention, the channel 640 can be formed as axially symmetrical with respect to the center point of the axis of the bushing hydraulic suspension 1. In other words, when the channel 640 is formed in the upper and lower parts of a bushing hydraulic suspension 1, the upper channel 640 and the lower channel 640 are positioned as symmetrical with respect to the axial direction of the axis of the bushing hydraulic suspension 1.

[0046] The upper guide portion 740 and the lower guide portion 740, which are adjacent to the upper channel 640 and the lower channel 640 respectively, are also configured to be axially symmetrical with respect to the axis of the bushing-type hydraulic suspension 1. Therefore, dual damping is provided for the vertical behavior of the bushing-type hydraulic suspension 1, thereby maximizing the damping.

[0047] The following will describe when along Figure 4A The direction of the arrow shown indicates the operation of the bushing-type hydraulic suspension 1 when an axial force is applied to it according to the invention.

[0048] Before a force is applied in the direction of the arrow, the bridging portion 440 is in position P. When an axial force is applied in the direction of the arrow, the bridging portion 440 slides backward on the outer tube 80 to position P1, while the first fixing portion 340 and the second fixing portion 540 remain fixed in their respective positions. The fluids in the front fluid chamber 140 and the rear fluid chamber 240 are oily substances with a low coefficient of friction, thus causing the bridging portion 440 to slide. The fluid volume in the front fluid chamber 140 increases while the fluid volume in the rear fluid chamber 240 decreases.

[0049] The front portion 442 of the bridging portion 440 is longer than the rear portion 446, as described below, and the end of the rear portion 446 becomes the contact portion 444 when the outer tube 80 is assembled. Therefore, when the bushing-type hydraulic suspension 1 moves axially, the bridging portion 400 can bend in only one direction and will not wobble from side to side. This improves durability and prevents noise that may occur when the orientation of the bridging portion 440 changes.

[0050] like Figure 4B As shown, when the rear fluid chamber 240 contracts, the fluid in the rear fluid chamber 240 flows through the channel 640 to the front fluid chamber 140 (as indicated by "W"), thereby providing damping. Specifically, since the two front fluid chambers 140 and the two rear fluid chambers 240 are respectively arranged axisymmetrically in the upper and lower parts of the bushing-type hydraulic mount 1 to provide dual damping for vertical behavior, the damping can be maximized.

[0051] refer to Figures 6A to 6H The assembly process of the bushing-type hydraulic suspension 1 according to the present invention is described.

[0052] The inner tube 20 is inserted into the middle tube 60, and then the main rubber 40 is vulcanized. Accordingly, the front fluid chamber 140, the rear fluid chamber 240, and the bridging portion 440 are located in the opening of the middle tube 60.

[0053] The outer tube 80 is assembled in fluid, during which the bushing-type hydraulic suspension 1 is filled with fluid. The outer tube 80 is assembled from the longer rear portion 446. As the outer tube 80 slides axially, the bridging portion 440 is compressed, thus separating the front fluid chamber 140 and the rear fluid chamber 240. When the outer tube 80 is assembled, the outer tube 80 compresses the bridging portion 440, which protrudes radially outward more than the middle tube 60, and the end of the bridging portion 440 bends forward. In addition, the longer rear portion 446 bends forward, and a portion of the end of the rear portion 446 becomes the contact portion 444. After the outer tube 80 is assembled, forging for sealing is performed at the first fixing portion 340 and the second fixing portion 540.

[0054] Figure 7A and 7B The front-to-back characteristics of the embodiment of the present invention (Figure E) and the comparative example were compared. In Comparative Example 1 (Figure C1), a conventional bushing-type rubber suspension with a front-to-back characteristic of 20 kgf / mm was used, and in Comparative Example 2 (Figure C2), a bushing-type rubber suspension with a higher front-to-back characteristic of 27 kgf / mm was used. In Comparative Example 2, the rubber properties were improved to a hardness of HS70 for principle evaluation, but as shown in the figure, it can be seen that there was no improvement or even a deterioration in some parts.

[0055] HS70 indicates the hardness of vulcanized rubber; the higher the number, the better the rubber's properties. Rubbers from HS35 to HS65 are typically used for suspension testing, while HS70 is used for principle testing. In an embodiment of the invention, a reduction in residual vibration was observed when front and rear damping was applied. Specifically, improved characteristics were found in the frequency range up to 13 to 18 Hz.

[0056] Existing bushing-type rubber mounts cannot improve axial characteristics, resulting in significant residual vibration due to the excessive fore-and-aft movement of the motor module in electric vehicles. According to the present invention, residual vibration can be reduced by increasing the axial damping value.

[0057] Furthermore, compared to conventional bushing-type suspensions, the increase in manufacturing cost and weight can be minimized because only a minimal number of components are added in this invention. While this invention includes a central tube 60 and a sealed fluid reservoir, unlike bushing-type rubber suspensions, the channel 640 is formed on the main rubber 40 through vulcanization, thus minimizing the increase in manufacturing cost and weight.

[0058] This invention utilizes a fluid chamber to provide damping performance based on the forward and backward behavior through the design of the compression bridging section. This structure can be achieved by vulcanizing the base rubber, preventing increases in manufacturing costs or weight.

[0059] According to the invention, the bridging portion 440 gradually tapers to one side and bends only to one side, so that it can maintain its shape even under axial behavior, thereby improving durability and ease of assembly and reducing noise.

[0060] According to the present invention, since the fluid chamber is vertically symmetrical, the characteristics in the three directions are separated, thereby optimizing the motor mounting system.

[0061] It will be apparent to those skilled in the art that the foregoing invention is not limited to the foregoing embodiments and the accompanying drawings, and that various modifications and changes can be made without departing from the scope and spirit of the invention.

Claims

1. A bushing-type hydraulic suspension, comprising: Inner tube; The middle tube is coaxially arranged with the inner tube; The main rubber, which is vulcanized between the inner tube and the middle tube; as well as The outer tube surrounds the middle tube. The main rubber comprises: The front fluid chamber is recessed from the surface of the main rubber; The rear fluid chamber is adjacent to the front fluid chamber and recessed from the surface of the main rubber. A bridging portion that separates the front fluid chamber and the rear fluid chamber, allowing fluid to flow between the two chambers, and the bridging portion is deformable by external force; and The channel is recessed from the surface of the main rubber and connects the front fluid chamber and the rear fluid chamber to each other. Each of the front fluid chamber, rear fluid chamber, bridging portion, and channel is configured to be vertically symmetrical and spaced apart from each other relative to the axial direction of the central tube, wherein the bridging portion includes: The front portion, which contacts the front fluid chamber; A contact portion that contacts the inner surface of the outer tube; and The rear portion, which contacts the rear fluid chamber, is longer than the front portion, and the end of the rear portion forms the contact portion, such that the bridging portion bends in only one direction.

2. The bushing-type hydraulic suspension according to claim 1, wherein, The bridging portion has a contact portion that contacts the outer tube and is movable relative to the outer tube by an external force.

3. The bushing-type hydraulic suspension according to claim 1, wherein, The bridging portion extends further outward in the radial direction than the central tube.

4. The bushing-type hydraulic suspension according to claim 1, wherein, When the outer tube is assembled, the bridging part forms a contact part that contacts the outer tube while bending along the assembly direction of the outer tube.

5. The bushing-type hydraulic suspension according to claim 1, wherein, The bridging portion gradually tapers to one side and its thickness decreases outward along the radial direction of the main rubber.

6. The bushing-type hydraulic suspension according to claim 2, wherein, The bridging portion bends to one side only relative to the axial direction of the bushing-type hydraulic suspension.

7. The bushing-type hydraulic suspension according to claim 1, wherein, The main rubber also includes: A guide portion is formed through and adjacent to the front fluid chamber, the rear fluid chamber, the bridging portion, and the channel.

8. The bushing-type hydraulic suspension according to claim 7, wherein, The channel and guide section are configured to be symmetrical about the axis of the central tube.

9. A method for assembling a bushing-type hydraulic suspension, comprising: A central tube with an axial opening and an inner tube located on the radially inner side are provided; A main rubber is vulcanized between an inner tube and a middle tube. The main rubber has a front fluid chamber, a rear fluid chamber, a bridging portion, and a channel. The front fluid chamber is recessed from the surface of the main rubber. The rear fluid chamber is adjacent to the front fluid chamber and is also recessed from the surface of the main rubber. The bridging portion is formed between the front and rear fluid chambers, protruding radially outward beyond the middle tube, and is deformable by external force. A first side serving as one side of the bridging portion is longer than a second side opposite to the first side. The channel is recessed from the surface of the main rubber and connects the front and rear fluid chambers to each other. The outer tube is assembled from the second side to surround the outer side of the middle tube, wherein each of the front fluid chamber, rear fluid chamber, bridging portion, and channel is configured to be vertically symmetrical and spaced apart from each other relative to the axial direction of the middle tube. The bridging component includes: The front portion, which contacts the front fluid chamber; A contact portion that contacts the inner surface of the outer tube; and The rear portion, which contacts the rear fluid chamber, is longer than the front portion, and the end of the rear portion forms the contact portion, such that the bridging portion bends in only one direction.

10. The method for assembling a bushing-type hydraulic suspension according to claim 9, further comprising: The two ends of the outer tube are forged.

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