JP2004098772A - Suspension device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve mounting stiffness of a rear bracket in relation to a chassis frame. <P>SOLUTION: This suspension device for a vehicle is provided with a left front bracket 14a, a right front bracket 14b, a left rear bracket 16a, and a right rear bracket 16b fixed to suspend a pair of leaf springs 12, 13 provided in front of the chassis frame 11 at both ends thereof. A support beam 26 is provided between the left rear bracket 16a and the right rear bracket 16b. Each rear bracket includes a pair of side plates 43 on which an upper end of a shackle 17 provided on a rear end of the leaf spring is pivotally supported, a connecting plate 44 fixed on a side member 11a and connecting the pair of side plates, and fixed plates 46 welded on the pair of side plates and the connecting plate. Both ends of the support beam 26 are fixed on the fixed plates. The support beam 26 is made of U-shaped steel sheet constructing a closed section with a cross member of the chassis frame 11. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a suspension system for a vehicle in which a front portion of a chassis frame of a vehicle is suspended on a front axle by a leaf spring.
[0002]
[Prior art]
Conventionally, a vehicle is provided with a front axle and a rear axle, and a chassis frame is suspended on these axles by a suspension device. As this suspension device, a device using a pair of leaf springs is known, and an axle is overlapped with a pair of leaf springs arranged in parallel so as to be orthogonal to each other, and an axle is provided at a central portion of each of the pair of leaf springs. Both sides are to be attached. Here, as shown in FIG. 5, both ends of the pair of leaf springs 1 and 1 are attached to a pair of side members 3a and 3a of the chassis frame 3 via brackets 2 and 2, respectively. On the other hand, a steering device is provided on a front axle on which the front part of the chassis frame 3 is suspended.
[0003]
Although not shown, tires and wheels are mounted on both sides of the front axle, the straightness is maintained by the grounding of the tires and the road surface, and the amount and position of the load Depending on the degree of curve running and the like, the brackets 2, 2 supporting both ends of the leaf springs 1, 1 to which the front axle is attached may be greatly inclined in the vehicle width direction with respect to the road surface. Assuming that the line connecting the centers of the left and right side members 3a, 3a in FIG. 5 is the XX axis, and the mounting surfaces of the shackles 4, 4, which are the mounting portions of the leaf springs 1, 1, are the YY axis, they are mounted. The angle is θ in the normal running, but changes to θ ′ in FIG. 6 when tilted. As a result, the chassis frame 3 is twisted, and self-excited vibration occurs due to the restoring force of the chassis frame 3. The self-excited vibration causes a so-called wobble phenomenon in which the vehicle body vibrates and the steering of the steering device vibrates violently. In particular, since the rear ends of the leaf springs 1, 1 are attached to the rear brackets 2, 2 via the shackles 4, 4, the chassis including the rear brackets 2, 2 for supporting the shackles 4, 4 and the side members 3a, 3a are included. If the overall rigidity of the frame 3 is insufficient, the wobble phenomenon cannot be effectively prevented.
[0004]
In order to solve this problem, the rigidity of the chassis frame 3 itself is increased by increasing the plate thickness of the side members 3a, 3a and the cross member 3b constituting the chassis frame 3, and a heavy engine is supported. The rigidity of the engine support is increased to increase the rigidity at least around the engine (for example, see Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 8-282531
[Problems to be solved by the invention]
However, increasing the plate thickness of the side members 3a, 3a and the cross member 3b to increase the rigidity of the chassis frame 3 itself increases the plate thickness in unnecessary portions, and increases the weight of the vehicle. There is. Further, increasing only the rigidity around the engine has a problem in that the rigidity balance with the front bracket is not balanced, and the wobble phenomenon cannot be effectively prevented.
An object of the present invention is to provide a vehicle suspension device that can relatively easily increase the mounting rigidity of a rear bracket to a chassis frame.
[0007]
[Means for Solving the Problems]
As shown in FIG. 1, the invention according to claim 1 includes a pair of leaf springs 12, 13 provided in front of a pair of side members 11 a, 11 b of the chassis frame 11 along the pair of side members 11 a, 11 b. This is an improvement of a vehicle suspension system including a left front bracket 14a, a right front bracket 14b, a left rear bracket 16a, and a right rear bracket 16b fixed to a pair of side members 11a and 11b, respectively, for suspension at both ends.
The characteristic configuration is that a support beam 26 is erected between the left rear bracket 16a and the right rear bracket 16b.
[0008]
In the vehicle suspension according to the first aspect, since the support beam 26 is provided between the left rear bracket 16a and the right rear bracket 16b, the left and right rear brackets 16a and 16b are tilted with respect to the chassis frame 11. Is prevented. Therefore, the so-called wobble phenomenon caused by the self-excited vibration for restoring the torsion is prevented without the torsion of the chassis frame 11.
According to the first aspect of the present invention, since the support beam 26 is simply provided between the conventionally provided left rear bracket 16a and right rear bracket 16b, the side members 11a, 11b and the cross It is not necessary to increase the thickness of the member 11c. Therefore, an increase in the weight of the vehicle can be suppressed as compared with the conventional case in which the plate thicknesses of the side members 11a and 11b and the cross member 11c are increased to increase their rigidity. Further, since it is not necessary to increase the thickness of the rear brackets 16a, 16b, the rigidity balance with the front brackets 14a, 14b can be balanced.
[0009]
The invention according to claim 2 is the invention according to claim 1, wherein the left rear bracket 16a and the right rear bracket 16b are provided at the rear ends of the leaf springs 12 and 13, respectively, as shown in FIG. A pair of side plates 43, 43 on which the upper ends of 17 are pivotally supported, a connecting plate 44 fixed to the side member 11a and connecting the pair of side plates 43, 43, and a rear end of the pair of side plates 43, 43 and the connecting plate 44 This is a vehicle suspension device having a fixed plate 46 welded thereto, and both ends of the support beam 26 fixed to the fixed plate 46 of the left rear bracket 16a and the fixed plate 46 of the right rear bracket 16b.
In the vehicle suspension according to the second aspect, since the left rear bracket 16a and the right rear bracket 16b each have the fixing plate 46, a relatively simple structure in which only the end of the support beam 26 is fixed to the fixing plate 46. The support beam 26 can be erected in the work.
[0010]
The invention according to claim 3 is the invention according to claim 2, and furthermore, as shown in FIG. 4, the support beam 26 is formed of a U-shaped steel plate forming a closed cross section together with the cross member 11c of the chassis frame 11. This is a vehicle suspension device.
In the vehicle suspension system according to the third aspect, since the support beam 26 is U-shaped, the support beams 26 are attached to the left and right rear brackets 16a, 16b fixed to the lower portions of the side members 11a, 11b so as to project downward. Both sides of the support beam 26 formed in a letter shape overlap from the rear. Since the support beam 26 forms a closed cross section together with the cross member 11c, the closed cross section can be prevented from collapsing, and the support beam 26 formed in a U-shape allows the left and right rear brackets 16a, 16b to be closed. Tilt can be effectively prevented.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a first embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, front portions of a pair of side members 11 a and 11 b of the vehicle that extend in the traveling direction of the chassis of the chassis frame 11 are provided with a pair of leaf springs 12 provided along the side members 11 a and 11 b. , 13. Left and right front brackets 14a and 14b and left and right rear brackets 16a and 16b are fixed to the front portions of the pair of side members 11a and 11b at predetermined intervals in the front-rear direction. The front ends of the leaf springs 12 and 13 are pivotally attached to the left and right front brackets 14a and 14b via a first pin 21, and the rear ends are via second pins 22 and 22, shackles 17, 17 and a third pin 23. It is pivotally attached to the left and left rear brackets 16a, 16b.
[0012]
A front axle 18 is provided below the pair of leaf springs 12 and 13 so as to extend in the vehicle width direction. A pair of spring receiving seats 18b, 18c are provided on the surface of the axle 18 facing the pair of leaf springs 12, 13, and the pair of leaf springs 12, 13 have their lower central surfaces mounted on the receiving seats 18b, 18c. In this state, it is fixed by U bolt 19. Here, although not shown, a stabilizer device may be provided between the pair of side members 11 a and 11 b of the chassis frame 11 and the front axle 18.
[0013]
The pair of leaf springs 12 and 13 have the same structure, and as a representative of the leaf spring 12 provided along the left side member 11a, as shown in detail in FIG. And has three main leaf springs 12a to 12c whose center is slightly curved downward. An eyeball portion 12e is formed at the front ends of the two main leaf springs 12a and 12b, and the eyeball portion 12e is pivotally connected via a first pin 21 to a left front bracket 14a fixed to a left side member 11a of the chassis frame 11. You. On the other hand, an eyeball portion 12f formed at the rear end of the two main leaf springs 12a and 12b is pivotally supported by the lower end of a shackle 17 whose upper end is pivotally attached to a left rear bracket 16a fixed to the left side member 11a. . The remaining one main leaf spring 12c is disposed below the two main leaf springs 12a, 12b, and both ends are attached to the two main leaf springs 12a, 12b by clips 24, 24. The centers of the three main leaf springs 13a to 13c are fixed to the upper surface of the front axle 18 by U bolts 19,19. The leaf spring 12 configured as described above is configured such that the front axle 18 attenuates vibrations and the like received from the road surface by bending, and the vibrations and the like are not transmitted to the chassis frame 11.
[0014]
As shown in detail in FIGS. 1 to 4, a characteristic configuration of the present invention is that a support beam 26 is installed between a left rear bracket 16a and a right rear bracket 16b. Since the left rear bracket 16a and the right rear bracket 16b have a symmetrical structure, the left rear bracket 16a will be described as a representative example of the left rear bracket 16a. An attachment portion 41 is attached to the side member 11a from the side, and a pivot portion 42 formed integrally with the attachment portion 41 and pivotally supporting the upper end portion of the shackle 17 via the collar 25 is provided. The mounting portion 41 and the pivot portion 42 are each made by sheet metal processing of a steel plate, and the mounting portion 41 and the pivot portion 42 formed by processing into a predetermined shape are welded, so that the pivot portion 42 is attached to the mounting portion 41. The left rear bracket 16a is integrally formed. In this embodiment, a single mounting hole 41a is formed in the mounting portion 41, and the bolt 37 (FIG. 2) inserted into the mounting hole 41a is further inserted into a not-shown insertion hole formed in the side member 11a. The attachment portion 41 is attached to the side member 11a by screwing a nut (not shown).
[0015]
On the other hand, the pivot portion 42 is provided with a collar 25 for pivotally supporting the third pin 23, and a pair of side plates 43, which pivotally support the upper end of the shackle 17 (FIGS. 1 and 2) via the third pin 23. 43, a connecting plate 44 provided in parallel with the collar 25 so as to connect the pair of side plates 43, 43, and a fixed plate welded so as to close the rear ends of the pair of side plates 43, 43 and the connecting plate 44. 46. The pair of side plates 43, 43 and the connecting plate 44 are integrally formed by bending a steel plate into a substantially U-shape by sheet metal processing, and the connecting plate 44 has two mounting holes 44a in this embodiment. It is formed. Bolts (not shown) inserted into the mounting holes 44a from below are further inserted through insertion holes (not shown) formed in the side members 11a, and nuts (not shown) are screwed into the connecting plates 44 to be fixed to the lower portions of the side members 11a. You. The periphery of the fixing plate 46 is welded to the rear ends of the pair of side plates 43, 43 and the connecting plate 44, and the fixing plate 46 has three mounting holes 46a in this embodiment.
[0016]
As shown in FIG. 4, the support beam 26 is formed by sheet metal processing a steel plate, and is formed in a U-shape that forms a closed cross section together with the cross member 11 c of the chassis frame 11. At both ends of the support beam 26, insertion holes (not shown) facing the mounting holes 46 a in the fixing plates 46 of the left rear bracket 16 a and the right rear bracket 16 b are formed. Then, the bolts 47 (FIG. 4) inserted into the insertion holes (not shown) are further inserted into the mounting holes 46a in the fixing plates 46 of the left and right rear brackets 16b, 16a, and the nuts (not shown) are screwed together. The end of the support beam 26 is fixed to the fixing plate 46. Thus, the support beam 26 is erected between the left rear bracket 16a and the right rear bracket 16b.
[0017]
In the vehicle suspension device configured as described above, the support beam 26 is provided between the left rear bracket 16a and the right rear bracket 16b, so that the left and right rear brackets 16a and 16b are prevented from tilting. . Particularly, in this embodiment, since the support beam 26 is formed in a U-shape, the support beam 26 is formed in a U-shape on the left and right rear brackets 16a, 16b fixed to the lower portions of the side members 11a, 11b so as to protrude downward. Since both sides of the support beam 26 overlap from the rear, the tilting of the left and right rear brackets 16a, 16b can be effectively prevented. Therefore, twisting of the chassis frame 11 due to the tilting of the left and right rear brackets 16a, 16b can be avoided, and so-called wobble phenomenon caused by self-excited vibration trying to restore the twist can be prevented.
[0018]
Here, according to the present invention, since the support beam 26 is simply installed between the conventionally provided left rear bracket 16a and right rear bracket 16b, the side members 11a and 11b and the cross member 11c are provided. Need not be increased. Therefore, an increase in the weight of the vehicle can be suppressed as compared with the conventional case in which the plate thicknesses of the side members 11a and 11b and the cross member 11c are increased to increase their rigidity. Further, since it is not necessary to increase the thickness of the rear brackets 16a, 16b, the rigidity balance with the front brackets 14a, 14b can be balanced.
[0019]
In the above-described embodiment, the description has been given using the flat support beam 26 made by sheet metal processing of a steel plate. However, the support beam 26 can prevent the left rear bracket 16a and the right rear bracket 16b from tilting. As long as the pipe is bent, a U-shaped support beam may be a steel plate on both sides and a middle part connected by a pipe.
[0020]
Further, in the above-described embodiment, a leaf spring having three main leaf springs 12a to 12c has been described. However, this leaf spring has five, four, or two main leaf springs. Alternatively, a leaf spring made of a single plate may be used. Also, the present invention can be applied to a front air suspension in which a leaf spring and an air spring are combined. In particular, when a leaf spring made of a single plate is used, the rigidity in the lateral direction may be reduced. However, in the present invention, the tilting of the left rear bracket 16a and the right rear bracket 16b can be prevented by the support beam 26. Therefore, the so-called falling phenomenon in which the leaf spring is twisted due to the tilting of the bracket can be effectively prevented.
[0021]
【The invention's effect】
As described above, according to the present invention, since the support beam is provided between the left rear bracket and the right rear bracket, the left and right rear brackets are prevented from tilting. Therefore, twisting of the chassis frame due to the tilting of the left and right rear brackets is prevented, and a so-called wobble phenomenon caused by self-excited vibration can be effectively prevented. Here, according to the present invention, it is not necessary to increase the thickness of the side member and the cross member. Therefore, an increase in the weight of the vehicle can be suppressed as compared with the related art in which the plate thickness of the side member and the cross member is increased to increase their rigidity. Also, since it is not necessary to increase the thickness of the rear bracket, the rigidity balance with the front bracket can be balanced.
[0022]
In addition, if a fixing plate is provided on the left rear bracket and the right rear bracket, the support beam can be erected by a relatively simple operation of fixing the end of the support beam to the fixing plate. Is formed in a U-shape, both sides of the U-shaped support beams overlap the left and right rear brackets from behind, and the left and right rear brackets are tilted by the U-shaped support beams. Can be effectively prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a suspension device of the present invention; FIG.
FIG. 3 is a perspective view showing a left rear bracket of the device.
FIG. 4 is a sectional view taken along line BB of FIG. 1;
FIG. 5 is a sectional view corresponding to FIG. 4, showing a conventional suspension device.
FIG. 6 is a sectional view corresponding to FIG. 5, showing a state where the conventional rear bracket is tilted.
[Explanation of symbols]
11 Chassis frame 11a, 11b Side member 12, 13 Leaf spring 14a Left front bracket 14b Right front bracket 16a Left rear bracket 16b Right rear bracket 17 Shackle 26 Support beam 43 Side plate 44 Connection plate 46 Fixing plate

Claims (3)

A pair of leaf springs (12, 13) provided along the pair of side members (11a, 11b) at the front of the pair of side members (11a, 11b) of the chassis frame (11) are suspended at both ends. And a left front bracket (14a), a right front bracket (14b), a left rear bracket (16a) and a right rear bracket (16b) fixed to the pair of side members (11a, 11b). , A support beam (26) is provided between the left rear bracket (16a) and the right rear bracket (16b). A left rear bracket (16a) and a right rear bracket (16b) are respectively provided with a pair of side plates (43, 43) on which upper ends of shackles (17) provided at rear ends of leaf springs (12, 13) are pivotally supported. A connecting plate (44) fixed to the side member (11a) and connecting the pair of side plates (43, 43); and a rear end of the pair of side plates (43, 43) and the connecting plate (44). Fixed plate (46),
The vehicle suspension according to claim 1, wherein both ends of the support beam (26) are fixed to a fixed plate (46) of the left rear bracket (16a) and a fixed plate of the right rear bracket (16b). The vehicle suspension according to claim 2, wherein the support beam (26) is made of a U-shaped steel plate having a closed cross section together with the cross member (11c) of the chassis frame (11).

Images