Roll center height adjustment mechanism

Abstract

The present invention provides a roll center height adjustment mechanism that allows the roll center position to be set to approximately the same position even for vehicles with different vehicle specifications. [Solution] An adjustment mechanism for adjusting the roll center height position in a suspension device 1 used in a vehicle, comprising: a lower arm 11 that supports the wheel 20 so as to be able to swing vertically relative to the vehicle body and is provided with an inclination that is lower to the vehicle body from below the rotation center Ax of the wheel and is directed upward toward the vehicle body; an upper arm 12 that supports the wheel so as to be able to swing vertically relative to the vehicle body and is provided with an inclination that is higher to the vehicle body from above the rotation center of the wheel and is directed downward toward the vehicle body; an intermediate mounting member 15 provided between the upper arm and the vehicle body and fixing the upper arm to the vehicle body; and a vehicle body mounting point 12a provided on the intermediate mounting member and to which the upper arm is fixed to the vehicle body, wherein the roll center height position is set according to different vehicle specifications at the vehicle body mounting point.

Description

Technical Field

[0001] This invention relates to an adjustment mechanism for adjusting the roll center height position in a suspension device used in vehicles such as automobiles.

Background Art

[0002] Conventionally, in vehicles such as automobiles, shortening the development period and reducing the manufacturing cost have always been desired. For this purpose, conventionally, for example, a design using a common platform has been widely carried out even among different vehicle types (vehicles having different vehicle specifications such as vehicle height (suspension posture and wheel outer diameter) and tread).

[0003] In this case, for example, it has been found that even if the vehicle specifications are different, by setting the roll center height position as a suspension parameter to be substantially the same, the handling performance and riding comfort performance can be maintained substantially the same. From this, setting the roll center height position to be substantially the same among different vehicle types leads to more efficient vehicle development.

[0004] Here, the roll center refers to the instantaneous center of the fulcrum when the left and right suspension devices of the vehicle start to move and the vehicle body rolls. The roll center can be shown, for example, in the case of a double wishbone type suspension device, as the intersection point where the line segment connecting the intersection of the extension lines of the lower arm and the upper arm and the ground contact point of the wheel intersects.

[0005] The roll center will be further briefly described using FIG. 4. FIG. 4 is a diagram for explaining the roll center, and schematically shows the left and right wheels of the vehicle and the suspension devices (double wishbone type) provided on the left and right wheels. In FIG. 4, it is assumed that the vehicle is viewed from the front or rear of the vehicle toward the vehicle front or rear.

[0006] In Figure 4, reference numeral 12 denotes the left and right upper arms of the left and right suspension devices. The left and right upper arms 12 have one end 12a and the other end 12b. Here, the one end 12a is fixed to the vehicle body and is a fixing part that supports the upper arm 12 so that it can swing freely. The other end 12b is fixed to the knuckle (not shown) on the wheel 20 side and is a point of action that follows the swinging of the knuckle.

[0007] In Figure 4, reference numeral 11 denotes the left and right lower arms of the left and right suspension devices. The left and right lower arms 11 have one end 11a and the other end 11b. Here, the one end 11a is fixed to the vehicle body and is a fixing part that supports the lower arm 11 so that it can swing freely. The other end 11b is fixed to the knuckle (not shown) on the wheel 20 side and is a point of action that follows the swing of the knuckle.

[0008] In this case, the extension of the line connecting one end 12a and the other end 12b of the left and right upper arms 12 is denoted by the symbol S. Similarly, the extension of the line connecting one end 11a and the other end 11b of the left and right lower arms 11 is denoted by the symbol T. The intersection points of these extensions S and T are called the instantaneous rotation centers M when the wheel 20 attempts to move up and down.

[0009] If we denote the straight lines connecting the instantaneous rotation center M and the center point TC of the wheel 20 that touches the ground as C (two lines), then the intersection point RC of these two straight lines C is called the roll center.

[0010] On the other hand, when using a common platform, the same suspension system may be applied to vehicles with different specifications, for example. In such configurations, it has been found that the setting of the roll center height position will vary depending on the vehicle specifications.

[0011] Therefore, when using the same suspension system across vehicles with different vehicle specifications, measures are taken to ensure that the roll center height position is set to the same level. For example, in the suspension system, (1) Lower the inner side (body mounting side) of the lower arm, or (2) Setting the inner side of the upper arm (the side attached to the vehicle body) to be raised. These are some possibilities.

[0012] In this case, for example, method (1) above would result in a low minimum ground clearance. Also, method (2) above would require different vehicle specifications (specifications for the upper arm mounting position on the vehicle body) for each vehicle specification, leading to problems such as the need for many different types of vehicles.

[0013] Incidentally, in conventional suspension systems, a suspension system equipped with a roll center variable mechanism that allows adjustment of the roll center height while the vehicle is in motion has been proposed, for example, in Japanese Patent Publication No. 2019-1328.

[0014] The roll center variable mechanism in the suspension device disclosed in Japanese Patent Publication No. 2019-1328, etc., is configured such that an arm mounting portion that moves up and down relative to the main body is attached to the upper arm. The arm mounting portion moves up and down by a drive mechanism including a motor, etc. This drive mechanism is driven and controlled by a suspension control device. [Prior art documents] [Patent Documents]

[0015] [Patent Document 1] Japanese Patent Publication No. 2019-1328 [Overview of the Initiative] [Problems that the invention aims to solve]

[0016] However, conventional suspension devices disclosed in Japanese Patent Publication No. 2019-1328 and others attempt to achieve driving stability by adjusting the roll center height of the vehicle while it is in motion. As a result, the device configuration becomes extremely complex, and there are problems with its large size and high cost.

[0017] The present invention aims to provide a roll center height adjustment mechanism that enables the setting of a roll center position at approximately the same location even for vehicles with different vehicle specifications, during the basic design stage of the vehicle. [Means for solving the problem]

[0018] To achieve the above objective, a roll center height adjustment mechanism according to one aspect of the present invention is an adjustment mechanism for adjusting the roll center height position in a suspension system used in a vehicle, comprising: a lower arm that supports a wheel so as to be able to swing vertically relative to the vehicle body and is provided with an inclination that is lower to the vehicle body from below the rotation center of the wheel and upward toward the vehicle body; an upper arm that supports the wheel so as to be able to swing vertically relative to the vehicle body and is provided with an inclination that is higher to the vehicle body from above the rotation center of the wheel and downward toward the vehicle body; an intermediate mounting member provided between the upper arm and the vehicle body for fixing the upper arm to the vehicle body; and a vehicle body mounting point provided on the intermediate mounting member for fixing the upper arm to the vehicle body, wherein the vehicle body mounting point is set to a roll center height position according to different vehicle specifications. [Effects of the Invention]

[0019] According to the present invention, it is possible to provide a roll center height adjustment mechanism that allows the roll center position to be set to substantially the same position even for vehicles with different vehicle specifications, at the stage of basic vehicle design. [Brief explanation of the drawing]

[0020] [Figure 1] A diagram showing the schematic configuration of a suspension device equipped with a roll center height position adjustment mechanism according to one embodiment of the present invention. [Figure 2] Figure 1 shows a second adjustment adapter applied to the roll center height position adjustment mechanism. [Figure 3]A diagram showing a modified example of a roll center height position adjustment mechanism according to an embodiment of the present invention. [Figure 4] A schematic diagram explaining the roll center.

Embodiments for Carrying Out the Invention

[0021] Hereinafter, the present invention will be described with reference to the illustrated embodiments. Each drawing used in the following description is shown schematically. Therefore, in each of these drawings, each component is shown in a size that can be recognized on the drawing. For this purpose, the dimensional relationships, scales, etc. of each member on the drawing may be shown differently for each component. The present invention is not limited only to the illustrated form with respect to the quantity, shape, size ratio, relative positional relationship, etc. of each component described in each drawing.

[0022] First, the schematic configuration of a suspension device including a roll center height position adjustment mechanism according to an embodiment of the present invention is shown below. FIG. 1 is a diagram showing the schematic configuration of a suspension device including a roll center height position adjustment mechanism according to an embodiment of the present invention. FIG. 2 is a diagram showing a second adjustment adapter applied to the roll center height position adjustment mechanism of FIG. 1. Note that the range indicated by the reference sign [A2] in FIG. 2 indicates substantially the same range as the range indicated by the reference sign [A1] in FIG. 1.

[0023] As shown in FIG. 1, the suspension device 1 including the roll center height position adjustment mechanism of the present embodiment shows a configuration example as a high-mount upper arm type double wishbone suspension device.

[0024] The configuration of the suspension device 1 basically has substantially the same configuration as a high-mount upper arm type double wishbone suspension device that has been generally put into practical use and widely spread in the past. In the present embodiment, it is different from the conventional one in that it includes a roll center height position adjustment mechanism. Therefore, the description of the configuration other than the roll center height position adjustment mechanism will be kept simple.

[0025] The suspension system 1 is composed of a lower arm 11, an upper arm 12, a knuckle 13, a shock absorber 14, and an adjustment adapter (see reference numeral 15 in Figure 1, reference numeral 15A in Figure 2), etc.

[0026] The lower arm 11 is a cantilevered arm member that is pivotably supported at one end by left and right fixing parts (not shown; see reference numeral 30 in Figure 1) such as the side frame of the vehicle (not shown), and is arranged to protrude outward in the lateral direction of the vehicle.

[0027] The lower arm 11 supports the wheel 20 (see Figure 1) so that it can swing vertically relative to the vehicle body (not shown). The lower arm 11 is positioned with an upward inclination from below the rotation axis Ax (see Figure 1) of the wheel 20 toward the vehicle body (not shown).

[0028] The lower arm 11 is configured such that, for example, two shaft members are arranged as two sides of a triangle or U-shape. Here, the other ends of the two shaft members intersect at the vertices of the two sides of the triangle or U-shape to form a point of application 11b. This point of application 11b is connected to a part of the lower side (first connecting part) of the knuckle 13, which will be described later. In addition, one end of each of the two shaft members (one end of each side of the triangle or U-shape) forms a pivot point 11a that is pivotably supported by the left and right fixed parts as described above. With this configuration, the lower arm 11 is formed in a cantilever-like shape that pivots at the two pivot points 11a, and pivotably supports the knuckle 13 connected to the point of application 11b.

[0029] The upper arm 12 is a cantilevered arm member that is pivotably supported at one end by a fixing member (for example, a part of the upper strut mount 14a, etc.) that is fixed to a fixing part (not shown; see reference numeral 31 in Figure 1) of the vehicle (not shown), and is arranged to protrude outward in the lateral direction of the vehicle.

[0030] The upper arm 12 supports the wheel 20 (see Figure 1) so that it can swing vertically relative to the vehicle body (not shown). The upper arm 12 is positioned with an inclination that extends downward from above the rotation axis Ax (see Figure 1) of the wheel 20 toward the vehicle body (not shown).

[0031] The upper arm 12 is configured such that, for example, two shaft members are arranged as two sides of a triangle or U-shape. Here, the other ends of the two shaft members intersect at the vertices of the two sides of the triangle or U-shape to form a point of application 12b. This point of application 12b is connected to a part of the upper side of the knuckle 13 (second connecting part), which will be described later. In addition, one end of each of the two shaft members (one end of each of the two sides of the triangle or U-shape) forms a pivot point 12a that is pivotably supported by a fixed part (for example, a part of the upper strut mount part 14a). With this configuration, the upper arm 12 is formed in a cantilever-like shape that pivots at the two pivot points 12a, and pivotably supports a part of the knuckle 13 that is connected to the point of application 12b.

[0032] The knuckle 13 is a member that rotatably supports the wheel hub 21, to which the disc brake device 22 and the wheel 20 are attached, about the rotational axis Ax. The knuckle 13 has a first connected portion to which the first connecting portion of the lower arm 11 is connected, and a second connected portion to which the second connecting portion of the upper arm 12 is connected.

[0033] The shock absorber 14 is a buffer that suppresses the expansion and contraction force of the coil spring (not shown) included in the suspension device 1. The upper end of the shock absorber 14 is supported by the upper strut mount portion 14a, and the lower end is supported by a part 11c of the lower arm 11.

[0034] The adjustment adapter 15 is an intermediate mounting member provided between the upper arm 12 and the vehicle body (not shown) to fix the upper arm 12 to the vehicle body. This adjustment adapter 15 (intermediate mounting member) is provided with a vehicle body mounting point (pivot) for fixing the upper arm 12 to the vehicle body. In this case, the vehicle body mounting point (pivot) is set to a position corresponding to the pivot point 12a of the upper arm 12.

[0035] The adjustment adapter 15 has, for example, a roughly L-shaped cross-section, with the longer side positioned to cover the upper strut mount portion 14a, and the shorter side extending downward from the plane of the upper strut mount portion 14a. A pivot (not shown) is provided on the shorter side to pivotably support the pivot point 12a.

[0036] In the roll center height position adjustment mechanism of this embodiment, a second adjustment adapter 15A is provided, which is an adjustment adapter 15 of the same form as described above, but with a different form. As an example of the configuration of the second adjustment adapter 15A, for example, a form with a different length dimension of the short side and a different pivot position provided on the short side is illustrated in Figure 2.

[0037] Here, the adjustment adapter 15 with its pivot position set to dimension L1, as shown in Figure 1, is referred to as the first adjustment adapter. In contrast, the second adjustment adapter 15A shown in Figure 2 has its pivot position set to dimension L2. Here, dimensions L1 and L2 are set such that L2 > L1.

[0038] In this case, the angle of inclination of the straight line connecting the point of application 12b and the pivot point 12a is different for the upper arm 12 when the first adjustment adapter 15 shown in Figure 1 is applied compared to the upper arm 12 when the second adjustment adapter 15A shown in Figure 2 is applied, as indicated by the sign [S1] in Figure 1 and the sign [S2] in Figure 2, respectively, with respect to the horizontal line.

[0039] In other words, when the first adjustment adapter 15 in Figure 1 is applied, and when the second adjustment adapter 15A in Figure 2 is applied, the position of the pivot point 12a of the upper arm 12 can be varied vertically. Therefore, the adjustment adapters 15 and 15A function as adjustment mechanisms for adjusting the roll center height position.

[0040] As described above, in the suspension device 1 equipped with the roll center height position adjustment mechanism of this embodiment, multiple types of adjustment adapters (15, 15A) with different pivot positions are prepared in advance, and the position of the pivot point 12a of the upper arm 12 can be set by simply selecting and using one of these multiple adjustment adapters (15, 15A) as appropriate. This makes it possible to adjust the roll center height position to a desired position as needed.

[0041] Therefore, when configuring vehicles with different vehicle specifications (for example, vehicle height (suspension posture and wheel diameter), tread (distance between the centers of the left and right wheels in the vehicle width direction)) using a common platform, even when applying the same suspension system, the roll center position can be set to approximately the same position by appropriately selecting and applying one of the multiple adjustment adapters (15, 15A).

[0042] Therefore, this makes it possible to maintain nearly identical handling and ride comfort performance between different vehicle models.

[0043] By the way, the above-described embodiment illustrates a configuration in which multiple types of adjustment adapters (15, 15A) with different pivot positions are provided. The present invention is not limited to the above-described embodiment. In addition to the above-described example, the following modifications are also conceivable.

[0044] Figure 3 shows a modified example of the roll center height position adjustment mechanism according to one embodiment of the present invention.

[0045] The adjustment adapter 15B illustrated by this modified example allows the pivot point 12a of the upper arm 12 to be selectively set to one of several positions using a single component.

[0046] As shown in Figure 3, the adjustment adapter 15B of this modified example has multiple (two in this example) pivots (15a, 15b) on its short side that are positioned differently in the vertical direction (along the short side).

[0047] Here, the first pivot 15a is located on the straight line [S1] connecting the pivot point 12a and the point of application 12b of the upper arm 12, and supports the pivot point 12a. The second pivot 15b is located on the straight line [S2] connecting the pivot point 12a and the point of application 12b of the upper arm 12, and supports the pivot point 12a.

[0048] In this way, the adjustment adapter 15B allows for adjustment of the desired roll center height position by selecting either the first pivot 15a or the second pivot 15b to support the pivot point 12a of the upper arm 12.

[0049] Therefore, with the adjustment adapter 15B of this modified example, one component can selectively set one of two positions for the pivot point 12a of the upper arm 12. This makes it possible to set a predetermined roll center height position according to the vehicle specifications, even for vehicle models with different vehicle specifications.

[0050] The present invention is not limited to the embodiments described above, and various modifications and applications can be implemented without departing from the spirit of the invention. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriate combinations of the multiple constituent elements disclosed. For example, if the problem that the invention aims to solve can be solved and the effects of the invention can be obtained even if some constituent elements are deleted from all the constituent elements shown in one embodiment, then the configuration with these deleted constituent elements can be extracted as an invention. Furthermore, constituent elements from different embodiments may be combined as appropriate. This invention is not limited by any particular embodiment other than being limited by the appended claims. [Explanation of Symbols]

[0051] 1…Suspension system 11…Lower arm 11a... Oscillation point 11b...point of action 12… Upper arm 12a... Oscillation point 12b...point of action 13... Knuckle 14…Shock absorber 14a... Upper strut mount section 15, 15A, 15B... Adjustment adapter 20...Wheel 21... Wheel hub 22… Disc brake system Ax... Rotational axis

Claims

1. An adjustment mechanism for adjusting the roll center height position in a suspension system used in a vehicle, A lower arm is provided to support the wheel so as to be able to swing vertically relative to the vehicle body, and is inclined upward toward the vehicle body from below the center of rotation of the wheel, An upper arm is provided to support the wheel so as to be able to swing vertically relative to the vehicle body, and is inclined downward toward the vehicle body from above the center of rotation of the wheel, An intermediate mounting member is provided between the upper arm and the vehicle body, and fixes the upper arm to the vehicle body. The intermediate mounting member is provided with a vehicle body mounting point to which the upper arm is fixed to the vehicle body, It is equipped with, The aforementioned vehicle body mounting point is set to a roll center height position according to different vehicle specifications. A roll center height position adjustment mechanism characterized by the following features.

2. The roll center height position adjustment mechanism according to claim 1, characterized in that the aforementioned vehicle specifications are at least one of the vehicle height and the tread, which is the distance between the centers of the left and right wheels in the vehicle width direction.

3. The roll center height position adjustment mechanism according to claim 2, characterized in that a plurality of intermediate mounting members are provided according to the type of vehicle specifications and are appropriately and selectively attached to the vehicle.

4. The roll center height position adjustment mechanism according to claim 2, characterized in that a plurality of vehicle body mounting points are provided according to the type of vehicle specifications, and the upper arm is appropriately and selectively fixed.

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