JP6971910B2 - Knuckle for vehicles - Google Patents

Description

The present invention relates to a vehicle knuckle that pivotally supports wheels.

Conventionally, a suspension unit that connects a vehicle body and wheels and supports the wheels is known. The suspension unit has a function of maintaining the posture of the wheels and a function of suppressing the transmission of unevenness (road noise) on the road surface to the vehicle body. Such a suspension unit is positioned as an important safety component in an automobile that requires high safety. The weight reduction of the suspension unit contributes to the kinetic performance of the automobile and the ride quality of the passenger. For this reason, in recent years, aluminum alloys have tended to be used instead of steel plates and cast iron for the members constituting the suspension unit.

Patent Document 1 discloses an aluminum steering knuckle. The knuckle is one of the members constituting the suspension unit, and has a function of connecting a suspension arm such as a lower arm or a steering rack to a hub that supports the wheels. In particular, in a support structure called a double wishbone system or a multi-link system, a knuckle called a high mount knuckle, which extends long in the vertical direction, is used.

Such a knuckle is required to have rigidity and strength against a load generated at a tire contact point of a wheel. In particular, as the rigidity required for the knuckle, high rigidity is required for a force from the outside to the inside in the vehicle width direction. Further, the strength required for the knuckle is high, and the strength against the force from the front side to the rear side of the vehicle is required to be high. Patent Document 2 discloses a knuckle structure that supports a pair of upper arms. A pair of upper arms are connected to a connecting portion provided at the upper end of the knuckle. By providing a bulging portion in which the connecting portion bulges in a mountain shape, the strength of the connecting portion of the knuckle is improved.

Japanese Unexamined Patent Publication No. 2014-091469 Japanese Unexamined Patent Publication No. 2016-060459

As described above, by making the knuckle for the vehicle constituting the suspension unit made of aluminum alloy, it is possible to contribute to the weight reduction of the automobile. In recent years, the strength of aluminum alloys has been improved, but their Young's modulus has not changed significantly. Therefore, when the weight of the knuckle is reduced by the aluminum alloy, there is a problem that it is difficult to secure the rigidity of the knuckle, particularly the rigidity against the force from the outside to the inside in the vehicle width direction.

The present invention has been made in view of the above points, and an object of the present invention is to improve the rigidity of an aluminum alloy vehicle knuckle against a force from the outside to the inside in the vehicle width direction.

As a means for solving the above-mentioned problems, the vehicle knuckle of the present invention is a vehicle knuckle made of an aluminum alloy, and has a bearing support portion that supports a bearing portion that forms a rotation axis of a wheel, and the bearing support portion. A knuckle upper portion extending upward from the knuckle and having an upper end portion of the knuckle, and a knuckle lower portion extending downward from the bearing support portion and connected to a lower arm, in a posture in which the vehicle knuckle is mounted on the vehicle body. When the upper part of the knuckle is equally divided into five or more regions along the vertical direction, the center of the bearing support portion is fixed, and a horizontal load from the outside to the inside in the vehicle width direction is applied to the upper end portion of the knuckle. The minimum value of the strain energy in each of the other regions excluding the region including the upper end of the knuckle and the region located at the uppermost position among the five or more regions divided by the mass of each corresponding region is the maximum value. The upper part of the knuckle has a shape of 0.70 or more.

According to this configuration, it is possible to improve the rigidity of the vehicle knuckle against a force from the outside to the inside in the vehicle width direction and to reduce the weight of the knuckle.

In the above configuration, it is desirable that the aluminum alloy material is formed by hot forging.

According to this configuration, the reliability and strength of the material structure of the vehicle knuckle can be improved.

In the above configuration, it is desirable that the 0.2% proof stress in the tensile test is 350 MPa or more.

According to this configuration, it is possible to promote weight reduction of the knuckle for a vehicle.

According to the present invention, it is possible to improve the rigidity of an aluminum alloy vehicle knuckle against a force from the outside to the inside in the vehicle width direction.

It is a perspective view of the suspension unit including the knuckle for a vehicle which concerns on one Embodiment of this invention. It is a schematic side view of the knuckle for a vehicle which concerns on one Embodiment of this invention. It is a schematic rear view of the knuckle for a vehicle which concerns on one Embodiment of this invention. It is sectional drawing which shows how the knuckle for a vehicle which concerns on one Embodiment of this invention is designed so that the width in the front-rear direction of a vehicle becomes small. It is a graph which shows the process of determining the shape of the knuckle for a vehicle which concerns on one Embodiment of this invention, and is the graph which shows the relationship between the partial mass of a knuckle for a vehicle, and strain energy. It is a graph which shows the process of determining the shape of the knuckle for a vehicle which concerns on one Embodiment of this invention, and is the graph which shows the relationship between the partial mass of a knuckle for a vehicle, and strain energy. It is a graph which shows the relationship between the change of mass (mass ratio) in the process of determining the shape of the knuckle for a vehicle which concerns on one Embodiment of this invention, and the maximum / minimum ratio of strain energy per unit volume. It is sectional drawing which shows how the knuckle for a vehicle which concerns on one Embodiment of this invention is designed so that the width in the vehicle front-rear direction and the thickness in the vehicle width direction are reduced.

Hereinafter, the high mount knuckle 11 (knuckle for a vehicle) according to an embodiment of the present invention will be outlined with reference to FIGS. 1 to 3. FIG. 1 is a perspective view of the suspension unit 10 including the high mount knuckle 11 according to the present embodiment. FIG. 2 is a schematic side view of the high mount knuckle 11. FIG. 3 is a schematic rear view of the high mount knuckle 11. In the directions shown in each figure, left (outside) and right (inside) mean the left direction toward the outside in the vehicle width direction and the right direction toward the inside in the vehicle width direction, respectively. do.

The suspension unit 10 is a unit mounted on the vehicle body of an automobile (not shown) and supports the wheels T of the automobile so as to be rotatable and steerable. As an example, in the present embodiment, the pair of suspension units 10 are arranged corresponding to the left and right front wheels of the automobile, respectively. The suspension unit 10 includes a high mount knuckle 11, a lower arm 12, a tie rod 14, a shock absorber 15, and a pair of upper arms 25.

The high mount knuckle 11 is a member made of an aluminum alloy that rotatably supports the wheel T and is connected to the lower arm 12 and the shock absorber 15. The high mount knuckle 11 has a bearing support portion 111, a knuckle lower portion 112, a knuckle upper portion 113, and a tie rod shaft support portion 114.

The bearing support portion 111 is a cylindrical portion extending along the vehicle width direction. The bearing support portion 111 supports a bearing portion (not shown) that forms the rotation axis of the wheel T. The shaft of the wheel T is inserted into the bearing support portion 111.

The knuckle lower portion 112 extends downward from the bearing support portion 111. The knuckle lower portion 112 has a knuckle lower end portion 116. The lower end portion 116 of the knuckle is arranged at the lower end portion of the lower end portion 112 of the knuckle, is connected to the lower end portion of the lower arm 152 of the shock absorber 15 via the lower joint 16, and is rotatably supported by the shaft.

The knuckle upper portion 113 extends upward from the bearing support portion 111. The knuckle upper portion 113 has a knuckle upper end portion 115. The upper end portion 115 of the knuckle is arranged at the upper end portion of the upper portion 113 of the knuckle, is connected to one end portion of each of the pair of upper arms 25 via the upper joint 17, and is rotatably supported by the shaft. The other ends of the pair of upper arms 25 are connected to the vehicle body so as to be rotatable in the vertical direction.

As shown in FIG. 1, the knuckle upper portion 113 of the high mount knuckle 11 extends upward from the bearing support portion 111 so as to bend inward in the vehicle width direction and then outward in the vehicle width direction, and as a result, the upper end portion of the knuckle. The 115 is located above the upper end of the wheel T. In other words, the bearing support portion 111 is arranged inside the wheel T, the knuckle upper end portion 115 is arranged above the wheel T, and the knuckle upper portion 113 is arranged inside in the vehicle width direction so as to avoid interference with the wheel T. It is curved, and as a result, the knuckle upper portion 113 has an arch shape that connects the bearing support portion 111 and the knuckle upper end portion 115. A knuckle axis L, which is a rotation axis of the high mount knuckle 11, is formed between the upper end portion 115 of the knuckle and the lower end portion 116 of the knuckle.

The tie rod shaft support 114 (FIGS. 1 and 2) extends rearward from the knuckle lower portion 112 below the bearing support 111. The tie rod shaft support 114 rotatably supports the tip portion 14S of the tie rod 14.

In this embodiment, the high mount knuckle 11 is integrally formed by hot forging of an aluminum alloy material. Further, as described later, the 0.2% proof stress in the tensile test of the high mount knuckle 11 is set to 350 MPa or more.

The lower arm 12 is a plate-shaped member having a substantially triangular shape in a plan view. The lower arm 12 has a front bush support portion 121, a rear bush support portion 122, and a joint support portion 123, respectively, which are located at the corners of the triangle. The front bush support portion 121 and the rear bush support portion 122 are arranged at intervals in the front-rear direction on the inside of the lower arm 12 in the vehicle width direction. The front bush support portion 121 receives the front bush 18 inside. Similarly, the rear bush support portion 122 receives the rear bush 19 inside. As a result, the lower arm 12 is swingably supported by a vehicle body (not shown) via the front bush 18 and the rear bush 19. At this time, the lower arm 12 can swing around the axis extending in the front-rear direction through the front bush 18 and the rear bush 19. In other words, the joint support portion 123 arranged on the outer side of the lower arm 12 in the vehicle width direction can move up and down about the axis.

The tie rod 14 extends from a steering gear box (not shown). The tie rod 14 has a tip portion 14S. The tip portion 14S is rotatably connected to the tie rod shaft support portion 114 of the high mount knuckle 11. When the tie rod 14 moves left and right as the vehicle is steered, the high mount knuckle 11 rotates around the knuckle axis L, and the wheel T is steered around the knuckle axis L.

The shock absorber 15 has a stretchable hydraulic cylinder 151, a lower arm 152, and a spring 15S. The hydraulic cylinder 151 is a main body portion of the shock absorber 15, and expands and contracts as the wheel T moves up and down according to the unevenness of the road surface. The spring 15S is arranged coaxially with the hydraulic cylinder 151 on the outer periphery of the upper portion of the hydraulic cylinder 151, and exerts a cushioning function by expanding and contracting according to the expansion and contraction of the hydraulic cylinder 151. The lower arm 152 is an arm portion extending downward from the hydraulic cylinder 151, and is pivotally supported by a joint support portion 123 of the lower arm 12 via a ball joint 20.

Such a suspension unit 10 is a suspension device between the vehicle body of the automobile and the wheels T, and has a function of holding the wheels T (tires) and maintaining the posture of the wheels T and the vehicle body of the road surface condition (road noise). It has a function to prevent transmission to. Therefore, each member constituting the suspension unit 10 is required to have high safety. Such weight reduction of each member of the suspension unit 10 contributes to weight reduction of the unsprung weight of the automobile, and greatly contributes to improvement of the kinetic performance of the automobile and the riding comfort of the driver. Therefore, among the weight reductions of automobiles, the weight reduction of the suspension unit 10 has a particularly high priority. Conventionally, steel plates and cast iron have been used for the suspension unit 10, but in recent years, the adoption of aluminum alloys has been increasing mainly in luxury cars. Further, each member of the suspension unit 10 is required to have rigidity, yield strength, and fatigue strength against external forces in various input directions. Further, each member of the suspension unit 10 is severely evaluated for its reliability in a corrosive environment.

Aluminum alloy has a density about 1/3 that of steel materials and has relatively high strength. Therefore, by replacing the material of the suspension unit 10 with an aluminum alloy from the steel plate or cast iron, it is generally possible to reduce the weight by about 40 to 60%. Among aluminum alloys, alloys and tempers with a higher 0.2% proof stress can generally obtain a higher weight reduction effect. Heat-treated 2000-series, 6000-series, and 7000-series alloys are suitable for such aluminum alloys from the viewpoint of material strength, but 2000-series and 7000-series alloys are inferior in corrosion resistance to 6000-series alloys. Therefore, for the suspension unit 10, 6000 series alloys having both strength and corrosion resistance, particularly 6082 alloys and 6061 alloys, and improved alloys having a similar composition are often adopted. In the case of such a 6000 series alloy, aging treatment by T6 treatment or T7 treatment is generally performed.

Among the members constituting the suspension unit 10, the high mount knuckle 11 and the lower arm 12 are formed by hot forging. In the present embodiment, the final shape is obtained through 2 to 4 hot forging steps. In this case, as compared with a plate material or an extruded profile, the degree of freedom in shape is high, and an arbitrary wall thickness and cross-sectional shape can be realized, so that a free structural design is possible.

Generally, the knuckle is a member constituting the suspension unit 10, and in the known double wishbone system and multi-link system, a knuckle called a high mount knuckle is used as in the present embodiment. The high mount knuckle 11 is required to have high rigidity and strength against a load at the tire contact point. As the rigidity, in particular, high rigidity against an external force from the outside to the inside in the vehicle width direction is required. On the other hand, as the strength, in particular, high strength against an external force from the front side to the rear side of the vehicle is required.

As described above, by making the high mount knuckle 11 constituting the suspension unit 10 made of an aluminum alloy, it is possible to contribute to the weight reduction of the automobile. In recent years, the strength of aluminum alloys has been improved, but their Young's modulus has not changed significantly. Therefore, when the weight of the high mount knuckle 11 is reduced by using an aluminum alloy, there is a problem that it is difficult to secure the rigidity of the high mount knuckle 11, particularly the rigidity against a force from the outside to the inside in the vehicle width direction.

In order to solve the above problems, in the present embodiment, the high mount knuckle 11 is characterized by the shape of the knuckle upper portion 113. In the posture in which the high mount knuckle 11 is mounted on the vehicle body of the automobile, the upper portion 113 of the knuckle is virtually divided into five regions along the vertical direction as shown in FIGS. 2 and 3. In FIG. 2, the length of the upper portion 113 of the knuckle in the vertical direction is defined as H. It is desirable that the length H is set in the range of 150 mm or more and 400 mm or less in order to further exhibit the effects described later. At this time, each of the five regions is defined as a first region 11A, a second region 11B, a third region 11C, a fourth region 11D, and a fifth region 11E in order from the top. The axis of the upper two bolts V of the four bolts V (FIG. 2) for fixing the bearing support portion 111 to the high mount knuckle 11 is aligned with the lower end portion of the fifth region 11E. , The first region 11A to the fifth region 11E are set. In other words, the knuckle upper portion 113 according to the present embodiment corresponds to a portion above the axial center of the two upper bolts V.

When the load received by the wheel T at the tire contact point is transmitted from the bearing support portion 111 to the high mount knuckle 11, the high mount knuckle 11 is fixed to the center of the bearing support portion 111 and is attached to the knuckle upper end portion 115 in the vehicle width direction. A so-called cantilever state is obtained in which a horizontal load F (FIG. 3) is applied from the outside to the inside.

According to the inventor of the present invention, such a cantilever (knuckle upper part 113) is virtually divided into regions 1, 2, 3 ... N, and the strain energy Ui is formed in a shape satisfying a predetermined bending rigidity. And when the mass Mi satisfies the following equation 1, it is derived from the strength of materials that the mass of the high mount knuckle 11 is set to the minimum.
Ui / Mi = constant (i = 1, 2, 3 ... N) ... (Equation 1)
It is desirable that the first region 11A including the knuckle upper end portion 115 of the knuckle upper portion 113 is excluded from the target of the formula 1 because the connection strength to the shock absorber 15 is required. That is, among the plurality of regions in which the cantilever (knuckle upper portion 113) is divided as described above, the other region (second region 11A) excluding the region including the knuckle upper end portion 115 and located at the uppermost position (first region 11A). It is desirable that the value obtained by dividing the strain energy in each of the regions 11B to the fifth region 11E) by the mass of each corresponding region is constant (Equation 1). On the other hand, considering the design process of the high mount knuckle 11, it is difficult to completely satisfy the equation 1. Therefore, the inventor of the present invention has found that the rigidity required for the high-mount knuckle 11 and the reduction in the design man-hours for the high-mount knuckle 11 are compatible when the following relationships are satisfied. That is, among the plurality of regions in which the cantilever (knuckle upper portion 113) is divided as described above, the other region (second region 11A) excluding the region including the knuckle upper end portion 115 and located at the uppermost position (first region 11A). The knuckle upper part 113 has a shape such that the minimum value obtained by dividing the strain energy in each of the regions 11B to the fifth region 11E) by the mass of the corresponding regions is 0.70 or more, which is the maximum value. Is desirable.

FIG. 4 is a cross-sectional view showing how the high mount knuckle 11 according to the present embodiment is designed so that the width in the vehicle width direction is reduced in the design process. FIG. 5 is a graph showing a process of determining the shape of the high mount knuckle 11 according to the present embodiment, and shows a partial mass (second region 11B to fifth region 11E) and strain energy of the high mount knuckle 11. It is a graph which shows the 1st Example of the relationship with. In the following embodiment, it is assumed that a horizontal load F having a size of 2000 N is applied to the upper end portion 115 of the knuckle. Further, the strain energy in each region (first region 11A to fifth region 11E) generated by the horizontal load F was calculated by Abaqus (finite element analysis software developed by HKS).

Table 1 shows the mass and strain energy in the first region 11A to the fifth region 11E of the first embodiment.

5 and 1 show how the high mount knuckle 11 is optimized in the order of shape 1-1, shape 1-2, and shape 1-3. At this time, as shown in FIG. 4, in the cross-sectional shape of the first region 11A to the fifth region 11E of the knuckle upper portion 113, the width W _{0 in the} vehicle front-rear direction is reduced to W', so that the mass of each region is reduced. Is reduced. First, the total weight of the high mount knuckle having the shape 1-1 is about 4000 g. Of the high mount knuckles, the shape of the lower part of the knuckle has not changed. Then, as shown in Table 1, the masses of the first region 11A to the fifth region 11E obtained by dividing the knuckle upper portion 113 of the shape 1-1 into five equal parts are distributed in 100 (g) to 1081 (g), respectively. , The mass increases from the top to the bottom. Further, the strain energies in each region are distributed in the range of 14 (mJ) to 134 (mJ). As a result, the strain energy per unit mass in each region is distributed in the range of 0.140 (J / kg) to 0.314 (J / kg). Then, in the second region 11B to the fifth region 11E excluding the first region 11A, the minimum / maximum value of the strain energy per unit mass in the shape 1-1 is 0.389 (= 0.122 / 0.314). ).

On the other hand, in the shape 1-2 in which the strain energy per unit mass in each region is leveled with respect to the shape 1-1, the masses of the first region 11A to the fifth region 11E are 128 (g) or more, respectively. It is distributed at 925 (g), and its mass increases from above to below. Further, the strain energy in each region is distributed in the range of 15 (mJ) to 130 (mJ). As a result, the strain energy per unit mass in each region is distributed in the range of 0.117 (J / kg) to 0.258 (J / kg). Then, in the second region 11B to the fifth region 11E excluding the first region 11A, the minimum / maximum value of the strain energy per unit mass in the shape 1-2 is 0.546 (= 0.141 / 0.258). ).

Further, in the shape 1-3 in which the strain energy per unit mass in each region is further leveled with respect to the shape 1-2, the masses of the first region 11A to the fifth region 11E are 160 (g), respectively. It is distributed in ~ 719 (g), and its mass increases from above to below. Further, the strain energies in each region are distributed in the range of 19 (mJ) to 131 (mJ). As a result, the strain energy per unit mass in each region is distributed in the range of 0.119 (J / kg) to 0.220 (J / kg). Then, in the second region 11B to the fifth region 11E excluding the first region 11A, the minimum / maximum value of the strain energy per unit mass in the shape 1-3 is 0.830 (= 0.182 / 0.220). ).

As described above, with the change from shape 1-1 to shape 1-3, the minimum / maximum value of strain energy per unit mass increases from 0.389 to 0.830, and the volume of strain energy increases. Allocation (leveling) has been achieved. At this time, although the mass of the knuckle upper part 113 of the high mount knuckle 11 was reduced by about 12% from 2322 (g) to 2047 (g), the rigidity of the knuckle upper part 113 (inversely proportional to the total strain energy) was increased. The result was an increase of about 16% (1/461 → 1/397). As shown in FIG. 5, as the shape of the high mount knuckle 11 is changed from the shape 1-1 to the shape 1-2 and the shape 1-3, the graph showing the relationship between the mass and the strain energy is at the zero point ( It can be seen that it is distributed around the straight line passing through the origin) and the correlation coefficient between the two changes so as to approach 1.

Similarly, FIG. 6 is a graph showing a process of determining the shape of the high mount knuckle 11 according to the present embodiment, and is a graph showing a partial mass of the high mount knuckle 11 (second region 11B to fifth region 11E). It is a graph which shows the 2nd Example of the relationship between a force and a strain energy.

Table 2 shows the mass and strain energy in the first region 11A to the fifth region 11E of the second embodiment.

6 and 2 show how the high mount knuckle 11 is optimized in the order of shape 2-1 to shape 2-2 and shape 2-3. Also in this case, as shown in FIG. 4, among the cross-sectional shapes of the first region 11A to the fifth region 11E of the knuckle upper portion 113, the width W _{0 in the} vehicle front-rear direction is reduced to W', so that each region The mass is reduced. In this embodiment, the total weight of the high mount knuckle having the shape 2-1 is about 5400 g. Of the high mount knuckles, the shape of the lower part of the knuckle will not be changed. Then, as shown in Table 2, the masses of the first region 11A to the fifth region 11E obtained by dividing the knuckle upper portion 113 of the shape 2-1 into five equal parts are distributed in 141 (g) to 1459 (g), respectively. , The mass increases from the top to the bottom. Further, the strain energy in each region is distributed in the range of 21 (mJ) to 229 (mJ). As a result, the strain energy per unit mass in each region is distributed in the range of 0.149 (J / kg) to 0.300 (J / kg). Then, in the second region 11B to the fifth region 11E excluding the first region 11A, the minimum / maximum value of the strain energy per unit mass in the shape 2-1 is 0.523 (= 0.157 / 0.300). ).

On the other hand, in the shape 2-2 in which the strain energy per unit mass in each region is leveled with respect to the shape 2-1 the masses of the first region 11A to the fifth region 11E are 142 (g) or more, respectively. It is distributed at 1337 (g), and its mass increases from above to below. Further, the strain energy in each region is distributed in the range of 20 (mJ) to 265 (mJ). As a result, the strain energy per unit mass in each region is distributed in the range of 0.141 (J / kg) to 0.300 (J / kg). Then, in the second region 11B to the fifth region 11E excluding the first region 11A, the minimum / maximum value of the strain energy per unit mass in the shape 2-2 is 0.661 (= 0.198 / 0.300). ).

Further, in the shape 2-3 in which the strain energy per unit mass in each region is further leveled with respect to the shape 2-2, the masses of the first region 11A to the fifth region 11E are 142 (g), respectively. It is distributed at ~ 1218 (g), and its mass increases from above to below. Further, the strain energy in each region is distributed in the range of 20 (mJ) to 285 (mJ). As a result, the strain energy per unit mass in each region is distributed in the range of 0.141 (J / kg) to 0.291 (J / kg). Then, in the second region 11B to the fifth region 11E excluding the first region 11A, the minimum / maximum value of the strain energy per unit mass in the shape 2-3 is 0.805 (= 0.234 / 0.291). ).

As described above, with the change from shape 2-1 to shape 2-3, the minimum / maximum value of strain energy per unit mass increases from 0.523 to 0.805, and the volume of strain energy increases. Allocation (leveling) has been achieved. At this time, although the mass of the knuckle upper part 113 of the high mount knuckle 11 could be reduced by about 12% from 3141 (g) to 2761 (g), the rigidity of the knuckle upper part 113 (inversely proportional to the total strain energy). , The results were almost the same (1/682 → 1/696). As shown in FIG. 6, as the shape of the high mount knuckle 11 is changed from the shape 2-1 to the shape 2-2 and the shape 2-3, the graph showing the relationship between the mass and the strain energy is at the zero point ( It can be seen that it is distributed around the straight line passing through the origin) and the correlation coefficient between the two changes so as to approach 1.

FIG. 7 is a graph showing the relationship between the change in mass (mass ratio) and the strain energy ratio per unit volume (minimum value / maximum value) in the process of determining the shape of the high mount knuckle 11 according to the present embodiment. be. More specifically, in FIG. 7, the shapes 1-1, 1-2 and 1-3 of Table 1 or the shapes 2-1 and 2-2 of Table 2 in the first and second embodiments are shown. The total mass of each region in 2-3 is plotted on the vertical axis, and the ratio of the minimum value / maximum value of the strain energy per unit mass is plotted on the horizontal axis. The vertical axis is indicated by the mass ratio with respect to the shape 1-1 or the shape 2-1. As shown in FIG. 7, the shape of the knuckle upper part 113 is set so that the ratio of the minimum value / the maximum value of the strain energy per unit mass is 0.70 or more, so that the knuckle upper part 113 of the high mount knuckle 11 Is reduced by 10% or more.

The high mount knuckle 11 (knuckle for a vehicle) according to the embodiment of the present invention has been described above. According to such a high mount knuckle 11, it is possible to improve the rigidity of the high mount knuckle 11 against a force from the outside to the inside in the vehicle width direction and to reduce the weight of the high mount knuckle 11. Since the high mount knuckle 11 is formed by hot forging of an aluminum alloy material, the reliability and strength of the material structure of the high mount knuckle for vehicles can be improved. Further, it is desirable that the 0.2% proof stress in the tensile test of the high mount knuckle 11 is 350 MPa or more. In this case, the weight reduction of the high mount knuckle for a vehicle can be promoted. The present invention is not limited to these forms. As the present invention, the following modified embodiments are possible.

(1) In the above embodiment, the knuckle for a vehicle according to the present invention has been described based on the high mount knuckle 11, but the present invention is not limited thereto. The present invention can also be applied to a vehicle knuckle made of an aluminum alloy having a shape (length) different from that of the high mount knuckle 11 described above. In order to improve the rigidity of the vehicle knuckle and reduce the weight of the vehicle knuckle, the length H of the region including the five regions 11A to 11E in FIG. 2 is set to the range of 150 mm to 400 mm as described above. It is desirable to set.

(2) In the above embodiment, the knuckle upper part 113 of the high mount knuckle 11 is divided into five regions, but the present invention is not limited thereto. The knuckle upper part 113 may be divided into six or more regions evenly.

(3) In the above embodiment, when the strain energy per unit mass in each region of the knuckle upper part 113 is leveled, the width in the front-rear direction in the cross-sectional shape of the knuckle upper part 113 is reduced as shown in FIG. However, the present invention is not limited thereto. FIG. 8 is a cross-sectional view showing how the high mount knuckle 11 according to the embodiment of the present invention is designed so that the width in the vehicle front-rear direction and the thickness in the vehicle width direction are reduced. As shown in FIG. 8, the knuckle upper 113 of the high mount knuckle 11 includes a U-shaped section, the width in the longitudinal direction of the vehicle is reduced from W ₀ to W ', T _W thickness in the vehicle width direction from the T _{W0 By} reducing to', the strain energy per unit mass in each region may be leveled.

Further, as described above, in the high mount knuckle 11 according to the present invention, the knuckle upper portion 113 is equally divided into five or more regions along the vertical direction in a posture mounted on the vehicle body of the automobile to support the bearing. When the center of the portion 111 is fixed and a horizontal load F from the outside to the inside in the vehicle width direction is applied to the knuckle upper end portion 115, the knuckle upper end portion 115 is included and is located at the uppermost position among the five or more regions. It is designed so that the minimum value of the strain energy in each of the other regions except the region (first region 11A) divided by the mass of each corresponding region is 0.70 or more, which is the maximum value. According to the design method, it is possible to improve the rigidity of the aluminum alloy high mount knuckle 11 (vehicle knuckle) against the force from the outside to the inside in the vehicle width direction and to reduce the weight of the high mount knuckle 11. Become.

10 Suspension unit 11 High mount knuckle (knuckle for vehicles)
111 Bearing support 112 Knuckle lower part 113 Knuckle upper part 114 Tie rod shaft support part 115 Knuckle upper end part 116 Knuckle lower end part 11A 1st area 11B 2nd area 11C 3rd area 11D 4th area 11E 5th area 12 Lower arm 121 Front bush support part 122 Rear Bush Support 123 Joint Support 14 Tie Rod 15 Shock Absorber 151 Hydraulic Cylinder 152 Lower Arm 153 Upper Arm 15S Spring 16 Lower Joint 17 Upper Joint 18 Front Bush 19 Rear Bush L Knuckle Axle Center T Wheel

Claims (3)

A vehicle knuckle made of aluminum alloy
A bearing support that supports the bearing that forms the axis of rotation of the wheel,
An upper part of the knuckle, which extends upward from the bearing support portion and has an upper end portion of the knuckle.
The lower part of the knuckle extending downward from the bearing support and connected to the lower arm,
Equipped with
In the posture in which the vehicle knuckle is mounted on the vehicle body, the upper portion of the knuckle is equally divided into five or more regions along the vertical direction, the center of the bearing support portion is fixed, and the upper end portion of the knuckle is fixed. Each corresponding strain energy in each of the five or more regions except the region located at the uppermost position including the upper end of the knuckle when a horizontal load is applied from the outside to the inside in the vehicle width direction. A vehicle knuckle having a shape in which the minimum value divided by the mass of the region is 0.70 or more, which is the maximum value, in the upper part of the knuckle. The vehicle knuckle according to claim 1, which is formed by hot forging of an aluminum alloy material. The vehicle knuckle according to claim 2, wherein the 0.2% proof stress in the tensile test is 350 MPa or more.

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