JP6788831B2 - Vehicle suspension - Google Patents

Description

The present invention relates to a vehicle suspension device.

Patent Document 1 describes an axle suspension for preventing displacement of the axle position in the event of a vehicle collision or the like. A leaf spring is attached to the chassis frame. A spring seat upper is brought into contact with the uppermost surface of the leaf spring, and the axle is tightened and fixed by the tightening axial force of two U bolts that hold the leaf spring through the spring seat upper. A U-bolt displacement regulating member is interposed between the uppermost surface of the leaf spring and the plurality of U-bolts. The U-bolt displacement regulating member is a wedge-shaped member having a tapered surface inclined rearward in the front-rear direction of the vehicle.

Japanese Unexamined Patent Publication No. 2000-301924

By the way, in a vehicle, in order to suppress the deflection of the vehicle due to the road surface cant, between one of the left and right leaf springs and the eye beam of the front axle, such as the U-bolt displacement regulating member described in Patent Document 1 above. The caster angle may be adjusted by interposing a wedge-shaped inclined plate. In this case, as the required caster angle is larger, the angle of the inclined plate is also increased, and the tightening direction of the U bolt with respect to the leaf spring is greatly inclined, so that the U bolt may be easily loosened.

Therefore, an object of the present invention is to provide a vehicle suspension device capable of suppressing loosening of U-bolts and suppressing deflection of the vehicle.

In order to solve the above problems, the present invention is a vehicle suspension device that supports a vehicle body frame from below, and includes a pair of left and right leaf springs, an eye beam, left and right inclined plates, and left and right U bolts. The left and right leaf springs are arranged on both left and right sides below the vehicle body frame and extend in the front-rear direction, and the front end portion and the rear end portion are connected to the vehicle body frame. The eye beam has a substantially I-shaped cross section, has an upper flange that intersects the vertical direction, extends along the vehicle width direction below the left and right leaf springs, and both ends thereof in the vehicle width direction than the left and right leaf springs. It is arranged on the outside and connected to each wheel. The left and right inclined plates are sandwiched between the upper surface of the upper flange of the eye beam and the lower surface of the left and right leaf springs. The left and right U-bolts are a horizontal bar that extends above the leaf spring in the vehicle width direction, and a pair of left and right vertical bars that bend downward from both the left and right ends of the horizontal bar and extend vertically on both the left and right sides of the leaf spring. The left and right vertical bar portions are fastened and fixed to the upper flange of the eye beam in a state where the left and right inclined plates are interposed between the eye beam and the left and right leaf springs. The thickness of one of the left and right inclined plates is thinner from the rear to the front. The thickness of the other inclined plate among the left and right inclined plates becomes thinner from the front to the rear.

In the above configuration, of the left and right inclined plates sandwiched between the upper surface of the upper flange of the eye beam and the lower surfaces of the left and right leaf springs, the thickness of one inclined plate becomes thinner from the rear to the front, and the other. Since the thickness of the inclined plate is thinner from the front to the rear, the caster angle on one side on the left and right is larger and the caster angle on the other side on the left and right is smaller than when the inclined plate is not provided. In this way, since the caster angle on one side can be increased with respect to the caster angle on the other side on the left and right, it is possible to suppress the deflection of the vehicle to one side. For example, in the case of a vehicle traveling on a road provided with a road surface cant that descends to the left, the caster angle on the left side can be increased and the caster angle on the right side can be decreased, so that the left deflection of the vehicle can be suppressed.

If you want to secure a relative predetermined angle difference between the left and right caster angles, use an inclined plate with an inclination angle that is half of the predetermined angle difference between the upper surface of the upper flange of the eye beam and the left and right leaf springs. It is possible to secure the above-mentioned predetermined angle difference between the left and right caster angles by interposing the caster angles in the opposite directions in the front-rear direction with the lower surface. Therefore, unlike the case where the tilt plate having the predetermined angle is provided on only one of the left and right sides, the tilt angle of the tilt plate can be suppressed to be small, so that the tilt of the eye beam with respect to the lower surface of the leaf spring in the side view can be suppressed to be small. Can be done. Therefore, since the inclination of the U-bolt in the tightening direction with respect to the leaf spring can be suppressed to be small, loosening of the U-bolt after fastening can be suppressed.

According to the present invention, it is possible to suppress loosening of the U bolt and suppress deflection of the vehicle.

It is an exploded view of the suspension device which concerns on one Embodiment of this invention. It is a schematic side view of the suspension system. It is a schematic side view of an eye beam, (a) shows one side in the vehicle width direction, and (b) shows the other side. It is the schematic of the vehicle traveling on the road provided with the road surface cant that descends to the left.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each figure, FR indicates the front of the vehicle, UP indicates the upper side, and IN indicates the inner side in the vehicle width direction. Further, in the following description, the left-right direction means the left-right direction in a state of facing the front of the vehicle.

As shown in FIG. 1, the axle suspension type suspension device 10 according to the present embodiment is the suspension device 10 on the front wheel 5 side of the vehicle 1. The vehicle body frame 2 of the vehicle 1 is a substantially ladder-shaped ladder frame, and has left and right side members 3 extending in the front-rear direction of the vehicle 1 on both sides in the vehicle width direction and left and right side members extending in the vehicle width direction. It has a plurality of cross members 4 connecting the three. Note that FIG. 1 shows the frontmost first cross member 4a and the second cross member 4b from the front among the plurality of cross members 4.

As shown in FIGS. 1 and 2, the suspension device 10 includes a pair of left and right leaf springs 11, a pair of left and right caster plates (tilted plates) 12, an eye beam 13, and two pairs of left and right U bolts 14. The left and right front wheels (wheels) 5 of the vehicle 1 are suspended, and the vehicle body frame 2 is supported from below. Since the left and right leaf springs 11 are symmetrically provided on the left and right sides of the vehicle 1 and have substantially the same configuration, the left side will be described below, and the detailed description on the right side will be omitted. Further, since the two pairs of U bolts 14 on the left and right have substantially the same configuration, one U bolt 14 will be described below, and the other description will be omitted.

The leaf spring 11 is a laminated leaf spring formed by vertically stacking a plurality of metal plate-like members long in the front-rear direction, and is arranged below the front portion of the side member 3 in the front-rear direction. Extend. The front end portion 11a and the rear end portion 11b of the leaf spring 11 are connected to the lower surface portion of the side member 3. The leaf spring 11 is curved so that the intermediate portion 11c between the front end portion 11a and the rear end portion 11b bulges downward in the side view (hereinafter, simply referred to as side view) of the vehicle 1. A center bolt 15 is fixed to the lower surface of the leaf spring 11 at a substantially central portion in the front-rear direction so as to project downward from the central portion in the vehicle width direction.

The left and right caster plates 12 are substantially rectangular plates with a top view intersecting the vertical direction, and have center bolt insertion holes 16 penetrating in the vertical direction at the central portions in the front-rear direction and the vehicle width direction. It is formed in a substantially triangular shape in the side view of 1. The length of the left and right caster plates 12 in the vehicle width direction is substantially the same as the length of the leaf spring 11 in the vehicle width direction. The left and right caster plates 12 have a substantially flat upper surface 21 and a substantially flat lower surface 23, and the thickness of one of the left and right caster plates 12 (the left side in the present embodiment) is the thickness of the caster plate 12L. The caster plate 12R on the other side (on the right side in this embodiment) is formed so as to be thinner from the rear to the front and thinner from the front to the rear. That is, the upper surface 21 and the lower surface 23 of the caster plate 12 are inclined to each other, the upper surface 21 and the lower surface 23 of the caster plate 12L on the left side intersect with each other on the front side, and the caster plate 12R on the right side has the upper surface 21. The lower surface 23 intersects with the lower surface 23 on the rear side. The left and right caster plates 12 are arranged below the left and right leaf springs 11 with the center bolts 15 of the left and right leaf springs 11 inserted through the center bolt insertion holes 16, and the lower surface of the leaf springs 11 and the eye beam described later. It is interposed between the spring seat portion 17 and the spring seat portion 17. The upper surface 21 of the caster plate 12 comes into surface contact with the lower surface 22 of the leaf spring 11, and the lower surface 23 of the caster plate 12 comes into surface contact with the upper surface 24 of the spring seat portion 17 of the eye beam 13. The caster plate 12 is sandwiched between the leaf spring 11 and the eye beam 13 to adjust the caster angle (hereinafter, simply referred to as the caster angle) on the front wheel 5 side of the vehicle 1.

The eye beam 13 is a metal structure having a substantially I-shaped cross section that is arranged below the left and right leaf springs 11 and extends in the vehicle width direction, and is arranged outside the vehicle width direction with respect to the left and right side members 3. It has left and right end portions 13a and 13b connected to the left and right front wheels 5. The eye beam 13 crosses the upper flange 18 extending in the vehicle width direction while intersecting the vertical direction, intersects the vertical direction at a position separated downward from the upper flange 18, extends in the vehicle width direction, and faces the upper flange 18. A substantially plate-like shape that is arranged between the side flange 19 and the upper flange 18 and the lower flange 19 and stands up along the vehicle width direction to connect the central portions of the upper flange 18 and the lower flange 19 in the front-rear direction. It has the web 20 of the above integrally. The eye beam 13 is arranged below the substantially central portion of the left and right leaf springs 11 in the front-rear direction and extends in the vehicle width direction. In the region below the left and right leaf springs 11 of the upper flange 18, a pair of left and right spring seat portions 17 having a substantially rectangular plate shape having a length in the front-rear direction longer than other regions of the upper flange 18 are provided. The spring seat portion 17 is formed with four bolt insertion holes 25 into which the U bolt 14 can be inserted. The four bolt insertion holes 25 penetrate the spring seat portion 17 of the upper flange 18 in the vertical direction. Two of the four bolt insertion holes 25 are formed in the spring seat portion 17 in front of the web 20, and the other two bolt insertion holes 25 are in the spring seat portion behind the web 20. It is formed at 17. The two bolt insertion holes 25 on the front side are separated from each other in the vehicle width direction, and the separation distance is longer than the length of the leaf spring 11 in the vehicle width direction. Further, the two bolt insertion holes 25 on the rear side are also separated from each other in the vehicle width direction, and the separation distance is longer than the length of the leaf spring 11 in the vehicle width direction. A hole 26 into which the tip of the center bolt 15 of the leaf spring 11 is inserted is formed in the substantially central portion of the spring seat portion 17. With the tip of the center bolt 15 of the leaf spring 11 inserted into the hole 26 of the spring seat 17, the upper surface (upper surface of the upper flange 18) 24 of the spring seat 17 of the eye beam 13 is the lower surface of the caster plate 12. Face contact with 23. In this way, the lower surface 23 of the caster plate 12 comes into surface contact with the upper surface 24 of the spring seat portion 17 of the eye beam 13, and the upper surface 21 of the caster plate 12 comes into surface contact with the lower surface 22 of the leaf spring 11. Adjusts the angle of the upper surface 24 of the spring seat portion 17 with respect to the lower surface 22 of the leaf spring 11 in the side view.

The U bolt 14 includes a horizontal bar portion 14a extending in the vehicle width direction above the leaf spring 11 and a pair of left and right vertical bar portions 14b, 14c that bend from both ends of the horizontal bar portion 14a in the vehicle width direction and extend downward. Have. The horizontal bar portion 14a is formed longer than the length of the leaf spring 11 in the vehicle width direction, and extends in the vehicle width direction above the spring pad 28 arranged above the upper surface 27 of the leaf spring 11. The left and right vertical bar portions 14b and 14c extend in the vertical direction on both the left and right sides of the leaf spring 11 and the caster plate 12, and the lower end portions thereof insert the bolt insertion holes 25 of the spring seat portion 17. A male screw is formed at the lower end of the U bolt 14 through which the bolt insertion hole 25 of the spring seat portion 17 is inserted. Of the two U-bolts 14 provided on one side in the vehicle width direction, the lower end of one U-bolt 14 inserts the two bolt insertion holes 25 on the front side of the spring seat portion 17, and the lower end of the other U-bolt 14. The portion inserts the two rear bolt insertion holes 25. With the lower end of the U bolt 14 inserting the bolt insertion hole 25 of the spring seat 17, the nut 28 is screwed into the male screw at the lower end of the U bolt 14, and the eye beam 13, the caster plate 12, and the leaf spring 11 Is fastened and fixed. It is not necessary to provide the spring pad 28 interposed between the horizontal bar portion 14a of the U bolt 14 and the upper surface 27 of the leaf spring 11, and the horizontal bar portion 14a of the U bolt 14 and the upper surface 27 of the leaf spring 11 are formed. May be in contact.

Next, the adjustment of the caster angle will be described with reference to FIGS. 2, 3 (a), 3 (b) and 4. In addition, in FIG. 3A and FIG. 3B, the state (state before adjustment) of the eye beam 13 before adjusting the caster angle is shown by a two-dot chain line, and the caster plate 12 according to the present embodiment is represented by the leaf spring 11. The state of the eye beam 13 (adjusted state) after adjusting the caster angle by interposing between the eye beam 13 and the eye beam 13 is shown by a solid line. Further, FIG. 3A shows one side (left side in this embodiment) in the vehicle width direction, and FIG. 3B shows the other side (right side in this embodiment). Further, in FIG. 4, the back surface of the vehicle traveling on the left side of the lane 6 is shown, and the front surface of the vehicle traveling on the right side of the lane 6 is shown.

As shown in FIG. 4, when traveling on a road provided with a downward-sloping road surface cant, in the state before adjusting the caster angle (see the two-dot chain line in FIGS. 3 (a) and 3 (b)). Since the caster angles are the same on the left and right sides of the vehicle 1, the vehicle 1 may be deflected to the left due to the road surface cant. The left deflection of this vehicle can be suppressed by increasing the left caster angle with respect to the right caster angle. For example, the left deflection of the vehicle can be suppressed by making the caster angle on the left side larger than the caster angle on the right side by a predetermined angle θ. In this case, the left and right caster plates are arranged so that the angle on the side where the lower surface 23 and the upper surface 21 of the left and right caster plates 12 intersect (the relative inclination angle between the lower surface 23 and the upper surface 21) is half an angle of θ. 12 is formed. Then, between the lower surface 22 of the leaf spring 11 on the left side and the upper surface 24 of the spring seat portion 17 on the left side of the eye beam 13, the caster plate 12 on the left side becomes thinner from the rear to the front. 12L is interposed, and the thickness of the caster plate 12 becomes thinner from the front to the rear between the lower surface 22 of the leaf spring 11 on the right side and the upper surface 24 of the spring seat portion 17 on the right side of the eye beam 13. The caster plate 12R on the right side is interposed. As a result, the caster angle on the left side with respect to the caster angle on the right side can be increased by a predetermined angle θ.

In the suspension device 10 configured as described above, since the caster angle on the left side is larger than the caster angle on the right side by a predetermined angle θ, the left deflection of the vehicle 1 when traveling on a road provided with a left-sloping road surface cant can be obtained. It can be suppressed.

Further, when it is desired to secure a relative angle difference (the above-mentioned predetermined angle θ) between the caster angle on the right side and the caster angle on the left side, the relative of the lower surface 23 and the upper surface 21 of the left and right caster plates 12 The left and right caster plates 12 are formed so that the inclination angle is half of θ, and the left and right are left and right between the lower surface 22 of the left and right leaf springs 11 and the upper surface 24 of the left and right spring seat portions 17 of the eye beam 13. The caster plates 12 of the above are interposed in the direction of inclination in opposite directions in the front-rear direction. Therefore, for example, a caster plate having a relative inclination angle between the lower surface 23 and the upper surface 21 of the caster plate having the predetermined angle θ is formed, and the caster plate is used with the lower surface 22 of the leaf spring 11 on one of the left and right sides. The inclination of the upper surface 24 of the spring seat 17 of the eye beam 13 with respect to the lower surface 22 of the leaf spring 11 on one side in the side view, unlike the case where the eye beam 13 is interposed only between the upper surface 24 of the spring seat 17 on one side. Can be kept small. Therefore, since the U bolt 14 can be tightened in a substantially vertical direction with respect to the lower surface 22 of the leaf spring 11, it is possible to suppress loosening of the U bolt 14 after fastening.

Therefore, according to the present embodiment, it is possible to suppress the loosening of the U bolt 14 and the deflection of the vehicle 1.

In the present embodiment, the suspension device 10 is applied to the vehicle 1 traveling on the road provided with the downward-sloping road surface cant, but the suspension device 10 is applied to the vehicle 1 traveling on the road provided with the downward-sloping road surface cant. May be applied. In this case, one of the left and right sides in the above description is the right side. That is, when the vehicle 1 suppresses the deflection to one of the left and right sides, the thickness of the caster plates 12 on the left and right sides is formed thinner from the rear to the front, and the caster plates 12 on the left and right sides are formed thinner. The plate thickness may be made thinner from the front to the rear.

Further, in the present embodiment, two pairs of left and right U bolts 14 are provided, but at least one pair of left and right U bolts 14 may be provided.

Further, in the present embodiment, the upper surface 21 of the caster plate 12 is brought into surface contact with the lower surface 22 of the leaf spring 11, and the lower surface 23 of the caster plate 12 is brought into surface contact with the upper surface 24 of the spring seat portion 17 of the eye beam 13. It is not limited to, and may be simply in contact with each other.

Further, in the present embodiment, the caster plate 12 is provided with a substantially flat upper surface 21 and a lower surface 23, but the present invention is not limited to this, and the upper surface 21 and the lower surface 23 of the caster plate 12 have irregularities. May be good. For example, the upper surface 21 is formed so that the thickness of one of the left and right caster plates 12 becomes thinner from the rear to the front, and the thickness of the other caster plate 12 becomes thinner from the front to the rear. And at least one of the lower surface 23 may be formed in a stepped manner.

Further, in the present embodiment, the upper surface 21 of the caster plate 12 is brought into surface contact with the lower surface 22 of the leaf spring 11, and the lower surface 23 of the caster plate 12 is brought into surface contact with the upper surface 24 of the spring seat portion 17 of the eye beam 13. The caster plate 12 is sandwiched between the lower surface 22 of the spring 11 and the upper surface 24 of the spring seat portion 17 of the eye beam 13, but the present invention is not limited to this. For example, with other members interposed between the upper surface 21 of the caster plate 12 and the lower surface 22 of the leaf spring 11, or between the lower surface 23 of the caster plate 12 and the upper surface 24 of the spring seat portion 17 of the eye beam 13. The caster plate 12 may be sandwiched between the lower surface 22 of the leaf spring 11 and the upper surface 24 of the spring seat portion 17 of the eye beam 13.

Although the present invention has been described above based on the above-described embodiment, the present invention is not limited to the contents of the above-described embodiment, and can be appropriately modified without departing from the present invention. That is, it goes without saying that all other embodiments, examples, operational techniques, and the like made by those skilled in the art based on this embodiment are included in the category of the present invention.

1: Vehicle 2: Body frame 5: Front wheels (wheels)
10: Suspension device 11: Left and right pair of leaf springs 11a: Front end of leaf spring 11b: Leaf spring rear end 12: Left and right pair of caster plates (tilted plates)
13: Eye beam 13a, 13b: Left and right end portions of eye beam 14: Left and right U bolts 14a: Horizontal rod portions 14b, 14c of U bolts: Left and right vertical rod portions 17: Spring seat portion 18: Upper flange 22: Lower surface of leaf spring 24: Upper surface of spring seat (upper surface of upper flange)

Claims (1)

A vehicle suspension device that supports the vehicle body frame from below.
A pair of left and right leaf springs arranged on both left and right sides below the vehicle body frame, extending in the front-rear direction, and connecting the front end portion and the rear end portion to the vehicle body frame
It has an upper flange that intersects the vertical direction, extends along the vehicle width direction below the left and right leaf springs, and both ends thereof are arranged outside the vehicle width direction with respect to the wheels. Eye beams with a substantially I-shaped cross section that are connected to each other
Left and right inclined plates sandwiched between the upper surface of the upper flange of the eye beam and the lower surfaces of the left and right leaf springs.
A horizontal bar portion extending in the vehicle width direction above the leaf spring and a pair of left and right vertical bar portions that are bent downward from the left and right ends of the horizontal bar portion and extend in the vertical direction on both the left and right sides of the leaf spring. With the left and right inclined plates interposed between the eye beam and the left and right leaf springs, the left and right vertical rod portions are fastened and fixed to the upper flange of the eye beam with the left and right U bolts. With,
The thickness of one of the left and right inclined plates is thinner from the rear to the front.
A vehicle suspension device characterized in that the thickness of the other inclined plate among the left and right inclined plates becomes thinner from the front to the rear.

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