Vehicle suspension system

Abstract

To provide a suspension device for a vehicle capable of preventing durability from decreasing due to friction between a leaf spring and a holding member and preventing abnormal sound.SOLUTION: A suspension device for a vehicle according to the present invention is a suspension device including a leaf spring, an engagement member that locks one end of the leaf spring, and a holding member that holds the other end of the leaf spring. The holding member includes a roller that holds the other end of the leaf spring and is rotatable following displacement of the other end of the leaf spring, and a pressing member that faces the roller. The other end of the leaf spring is provided between the roller and the pressing member.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a suspension device for a vehicle.

Background Art

[0002] Conventionally, a suspension device is known that is provided in a vehicle or the like and has a buffering function to prevent vibrations caused by unevenness of the road surface from being transmitted to the vehicle body via the wheels, and improves the riding comfort and steering stability of the vehicle. Among suspension devices, a leaf spring type suspension device is configured using a leaf spring (for example, see Patent Document 1).

[0003] The leaf spring described in Patent Document 1 has one end fixed to the vehicle body and the other end held slidably via a slide sheet. This leaf spring is loaded with a load from an axle or the like at the central portion in the longitudinal direction and is deformed by this load.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when the end of the leaf spring is held by a slide sheet as in Patent Document 1, there may be a decrease in durability due to wear caused by friction between the slide sheet and the leaf spring, and abnormal noise may occur due to friction during sliding.

[0006] The present invention has been made in view of the above, and an object thereof is to provide a vehicle suspension device capable of suppressing a decrease in durability due to friction between a leaf spring and a holding member and the generation of abnormal noise.

Means for Solving the Problems

[0007] To solve the above-mentioned problems and achieve the objective, the vehicle suspension device according to the present invention is a suspension device comprising a leaf spring, a locking member to which one end of the leaf spring is locked, and a holding member to which the other end of the leaf spring is held, wherein the holding member has a roller that holds the other end of the leaf spring and is rotatable in accordance with the displacement of the other end of the leaf spring, and a pressing member facing the roller, and the other end of the leaf spring is provided between the roller and the pressing member.

[0008] Furthermore, the vehicle suspension system according to the present invention is characterized in that the leaf spring is held between a roller and a retaining member.

[0009] Furthermore, the vehicle suspension device according to the present invention is characterized by further comprising a biasing member that biases the roller and the pressing member in a direction that brings them closer together.

[0010] Furthermore, the vehicle suspension device according to the present invention is characterized in that the retaining member is a roller that can rotate in accordance with the displacement of the other end of the leaf spring.

[0011] Furthermore, the vehicle suspension device according to the present invention is characterized in that, in the above invention, at least one recess is formed on the outer circumferential surface of the roller.

[0012] Furthermore, the vehicle suspension device according to the present invention is characterized in that, in the above invention, at least one recess is formed on the outer circumferential surface of at least one of the roller and the pressing member.

[0013] Furthermore, the vehicle suspension device according to the present invention is characterized in that the roller has a shaft portion and a rotating portion provided on the outer circumference of the shaft portion and rotatable relative to the shaft portion, and the rotating portion includes an elastic material.

[0014] Furthermore, the vehicle suspension device according to the present invention is characterized in that, in the above invention, a projection is formed on at least one end of the roller in the axial direction, projecting in a direction intersecting the axial direction. [Effects of the Invention]

[0015] According to the present invention, the reduction in durability due to friction between the leaf spring and the retaining member, as well as the generation of abnormal noise, can be suppressed. [Brief explanation of the drawing]

[0016] [Figure 1] Figure 1 shows a diagram illustrating a part of the configuration of a vehicle including a suspension system according to one embodiment of the present invention. [Figure 2] Figure 2 is a diagram illustrating the configuration of a leaf spring in a suspension device according to one embodiment of the present invention. [Figure 3] Figure 3 shows the configuration of the rollers of a suspension device according to Modification 1 of the present invention. [Figure 4] Figure 4 shows the configuration of the rollers of a suspension device according to Modification 2 of the present invention. [Figure 5] Figure 5 shows the configuration of the gripping member of a suspension device according to Modification 3 of the present invention. [Modes for carrying out the invention]

[0017] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "embodiments") will be described with reference to the attached drawings. Note that the drawings are schematic, and the relationship between the thickness and width of each part, the ratio of the thickness of each part, etc., may differ from reality, and there may be parts where the dimensional relationships and ratios differ between drawings.

[0018] (Embodiment) FIG. 1 is a diagram showing a partial configuration of a vehicle including a suspension device according to an embodiment of the present invention. The suspension device 1 shown in FIG. 1 is provided on the vehicle body of the vehicle and supports an axle 100 that supports a wheel 101. In FIG. 1, the left side is the front of the vehicle and the right side is the rear. The suspension device 1 includes a leaf spring 2, a locking member 3 to which one end of the leaf spring 2 is locked, and a holding member 4 that holds the other end of the leaf spring 2 so as to be able to advance and retreat.

[0019] The locking member 3 and the holding member 4 are attached to the frame 110. Specifically, the locking member 3 is fixed to a front mounting portion 120 that is fixed to the frame 110. The holding member 4 is fixed to a rear mounting portion 130 that is fixed to the frame 110. The front mounting portion 120 and the rear mounting portion 130 are fixed to the frame 110 by fastening members such as screws. Further, the locking member 3 is attached to the front mounting portion 120 by welding or the like. Further, the holding member 4 is attached to the rear mounting portion 130 by welding or the like. Note that the locking member 3 and the holding member 4 may be integrally formed with the front mounting portion 120 and the rear mounting portion 130, respectively.

[0020] Insertion holes (not shown) are formed at the center in the longitudinal direction of the leaf spring 2 and at the center of the washer 140. The leaf spring 2 and the washer 140 form a leaf spring assembly that is fixed by fastening a center bolt 140a inserted through each insertion hole to a nut 140b. The leaf spring assembly is fixed to the housing 160 by a U-bolt 150. The housing 160 is fixed to the axle 100.

[0021] FIG. 2 is a diagram for explaining the configuration of a leaf spring of a suspension device according to an embodiment of the present invention. The leaf spring 2 has a main body portion 20 formed by bending one end of a strip-shaped member, a hook-shaped first end portion 21 provided on one end side of the main body portion 20, and a second end portion 22 provided on the other end side of the main body portion 20. The main body portion 20 has an axle 100 disposed below the main body portion 20 at the central portion in the longitudinal direction. The first end portion 21 is locked by being wound around a locking member 3. The leaf spring 2 is formed using a metal material (for example, spring steel), a resin material, or a fiber reinforced plastic (FRP).

[0022] The holding member 4 is composed of two paired rollers (a first roller 41 and a second roller 42). The first roller 41 has a first shaft portion 41a connected to the rear mounting portion 130 and a first rotating portion 41b rotatable with respect to the first shaft portion 41a. The first rotating portion 41b is connected to the first shaft portion 41a via, for example, a bearing and rotates around the central axis N1 of the first shaft portion 41a. The second roller 42 has a second shaft portion 42a connected to the rear mounting portion 130 and a second rotating portion 42b rotatable with respect to the second shaft portion 42a. The second rotating portion 42b is connected to the second shaft portion 42a via, for example, a bearing and rotates around the central axis N2 of the second shaft portion 42a. The distance (gap) between the first roller 41 and the second roller 42 is equivalent to the thickness of the leaf spring 2. Therefore, in a state where the leaf spring 2 is disposed between the rollers, the first roller 41 and the second roller 42 respectively contact the leaf spring 2 and grip the leaf spring 2. Here, the so-called equivalent includes manufacturing errors and the like. The first shaft portion 41a and the second shaft portion 42a are formed using, for example, a metal material. Also, the first rotating portion 41b and the second rotating portion 42b are formed using, for example, a metal material, a resin material, rubber, or the like. By forming the rotating portion using an elastic material such as rubber or a soft resin, a damping effect can be obtained. Furthermore, the damping effect can be adjusted by adjusting the distance between the first shaft portion 41a and the second shaft portion 42a. The first roller 41 and the second roller 42 are rollers and pressing members that face each other and have the ends of the leaf spring 2 provided between them.

[0023] The leaf spring 2 deforms in response to vibrations of the axle 100 caused by uneven road surfaces, etc. (see dashed line in Figure 2). The second end 22 is held by the retaining member 4 by being sandwiched between the first roller 41 and the second roller 42. When the second end 22 is displaced relative to the retaining member 4 due to the deformation of the leaf spring 2, the length between the locking member 3 of the leaf spring 2 and the retaining member 4, i.e., the effective span of the leaf spring 2, changes, and thus the load characteristics of the leaf spring 2 change. At this time, the first rotating part 41b and the second rotating part 42b rotate in response to the displacement of the second end 22, thereby suppressing the generation of friction between them and the second end 22.

[0024] In the embodiment of the present invention described above, in the leaf spring 2 that deforms in response to the vibration of the axle 100, one end is locked to the vehicle body (here, the frame 110), and the other end is gripped by a first roller 41 and a second roller 42, and the first roller 41 and the second roller 42 rotate in response to the displacement of the other end due to deformation. According to this embodiment, the rotation of the rollers suppresses the occurrence of friction between the leaf spring 2 and the retaining member 4, thereby suppressing a decrease in durability due to friction between the leaf spring and the retaining member, and the generation of abnormal noise.

[0025] In this case, if the end of the leaf spring is held by a sliding sheet, and the leaf spring 2 breaks in front of the axle, the leaf spring 2 body rotates around the rear end connection, bringing the axle closer to the vehicle body, resulting in a significant drop in vehicle height. In contrast, as in this embodiment, when the leaf spring 2 is clamped by rollers, even if the leaf spring 2 breaks on the front side, a repulsive force is generated on the rear side due to the clamping, thus suppressing a significant drop in vehicle height.

[0026] Furthermore, according to this embodiment, by holding the leaf spring 2 with rollers, it is possible to give the leaf spring 2 nonlinear characteristics with a simpler structure compared to conventional leaf springs in which a main spring and a sub-spring are stacked.

[0027] Furthermore, in this embodiment, by making the thickness of the rotating part uniform with respect to the rotating shaft, the resistance that the leaf spring receives from the roller can be made uniform, thereby improving vibration damping and durability.

[0028] (Variation 1) Next, a modification 1 of the embodiment of the present invention will be described with reference to Figure 3. Figure 3 is a diagram showing the configuration of the rollers of the suspension device according to modification 1 of the present invention. The suspension device according to modification 1 is equipped with a roller 43 in place of the first roller 41 and the second roller 42 of the holding member 4. The other components are the same as those in the embodiment, so their description will be omitted.

[0029] The roller 43 has a shaft portion 43a connected to the rear mounting portion 130 and a rotating portion 43b that is rotatable relative to the shaft portion 43a. The rotating portion 43b is connected to the shaft portion 43a, for example, via a bearing, and rotates around the central axis N3 of the shaft portion 43a.

[0030] The rotating part 43b has a main body 431 which is hollow and cylindrical and through which the shaft 43a is inserted, a first projection 432 provided on one end of the main body 431 and projecting outward from the outer circumferential surface of the main body 431, and a second projection 433 provided on the other end of the main body 431 and projecting outward from the outer circumferential surface of the main body 431. The first projection 432 and the second projection 433 protrude to such an extent that they do not interfere with the projections of the other rollers in the pair. These projections only need to protrude in a direction intersecting the central axis N3. The second end portion 22 of the leaf spring 2 passes between the first projection 432 and the second projection 433.

[0031] In the modified example 1 described above, similar to the embodiment, the leaf spring 2 that deforms in response to the vibration of the axle 100 has one end locked to the vehicle body (frame 110 in this case) and the other end gripped by two rollers 43, and the rollers 43 rotate in accordance with the displacement of the other end due to deformation. According to this modified example 1, the rotation of the rollers 43 suppresses the occurrence of friction between the leaf spring 2 and the retaining member 4, thereby suppressing a decrease in durability due to friction between the leaf spring and the retaining member, and the generation of abnormal noise.

[0032] Furthermore, according to Modification 1, since the leaf spring 2 passes between the first projection 432 and the second projection 433, displacement of the leaf spring 2 in the direction of the central axis N3 can be suppressed.

[0033] In the modified example 1, one roller may be composed of roller 43, and the other roller may be composed of the first roller 41 or the second roller 42.

[0034] Furthermore, in the modified example 1, a projection may be provided only on one end of the roller 43, and the projections of the pair of rollers may be positioned on opposite sides to suppress the detachment of the leaf spring 2.

[0035] In the modified example 1, the projection is provided at the end of the roller 43 in the direction of the central axis N3. However, it does not need to be at the end, as long as it is a position that can grip the leaf spring 2 with the roller while suppressing the displacement of the leaf spring 2 in the direction of the central axis N3.

[0036] (Modification 2) Next, a second modification of the embodiment of the present invention will be described with reference to Figure 4. Figure 4 is a diagram showing the configuration of the rollers of the suspension device according to the second modification of the present invention. The suspension device according to the second modification is equipped with a roller 44 in place of the first roller 41 and the second roller 42 of the holding member 4. The other components are the same as those in the embodiment, so their description will be omitted.

[0037] The roller 44 has a shaft portion 44a connected to the rear mounting portion 130 and a rotating portion 44b that is rotatable relative to the shaft portion 44a. The rotating portion 44b is connected to the shaft portion 44a, for example, via a bearing, and rotates around the central axis N4 of the shaft portion 44a.

[0038] The rotating part 44b has a main body 441 which is hollow and cylindrical and through which the shaft 44a is inserted, a first projection 442 provided on one end of the main body 441 and projecting from the outer circumferential surface of the main body 441, and a second projection 443 provided on the other end of the main body 441 and projecting from the outer circumferential surface of the main body 441. The second end 22 of the leaf spring 2 passes between the first projection 442 and the second projection 443. The first projection 442 and the second projection 443 protrude to such an extent that they do not interfere with the projections of the other rollers in the pair. These projections only need to protrude in a direction intersecting the central axis N4.

[0039] The main body portion 441 has a plurality of recesses 444 formed on its outer circumferential surface. The recesses 444 extend in the circumferential direction and encircle the main body portion 441.

[0040] In the modified example 2 described above, similar to the embodiment, the leaf spring 2 that deforms in response to the vibration of the axle 100 has one end locked to the vehicle body (frame 110 in this case) and the other end gripped by two rollers 44, and the rollers 44 rotate in response to the displacement of the other end due to deformation. According to this modified example 2, the rotation of the rollers 44 suppresses the occurrence of friction between the leaf spring 2 and the retaining member 4, thereby suppressing a decrease in durability due to friction between the leaf spring and the retaining member, and the generation of abnormal noise.

[0041] Furthermore, according to the modified example 2, since a recess 444 is formed in the main body 441, when foreign matter enters the roller 44 from the outside, or when foreign matter attached to the leaf spring 2 adheres to the roller 44, the foreign matter can be contained in the recess 444, thereby maintaining the contact state between the leaf spring 2 and the roller 44 and suppressing damage to the leaf spring 2 caused by foreign matter.

[0042] In the modified example 2, one roller may be composed of roller 44, and the other roller may be composed of the first roller 41, the second roller 42, and roller 43.

[0043] In addition, in the modified example 2, the roller 44 may be configured without any protrusions. Furthermore, while the 2nd modified example described an example of multiple recesses 444 extending in the circumferential direction, the invention is not limited to this. For example, a single recess 444 may be formed, or a recess may be formed that extends spirally around the axis N4, or a plurality of recesses forming a hole shape (e.g., embossing) may be formed. Furthermore, in the configuration shown in Figure 2, when applying the configuration of modified example 2, the recess may be formed on only one roller, or it may be formed on both one roller and the other roller.

[0044] (Variation 3) Next, a third modification of the embodiment of the present invention will be described with reference to Figure 5. Figure 5 is a diagram showing the configuration of the rollers of the suspension device according to the third modification of the present invention. The suspension device according to the third modification includes a retaining member 4A instead of the retaining member 4. In addition, the rollers 41 and 42 of the retaining member 4A are attached to the frame 100 so as to be relatively movable. The other components have the same configuration as in the embodiment, so their description will be omitted. The same reference numerals are used for the same components.

[0045] The retaining member 4A comprises two rollers (a first roller 41 and a second roller 42), a first spring member 45 connecting the axial ends of the two rollers, and a second spring member 46 connecting the axial ends of the two rollers. The first spring member 45 connects one end of the first shaft portion 41a in the direction of axis N1 (see Figure 2) and one end of the second shaft portion 42a in the direction of axis N2 (see Figure 2) in a retractable manner. The second spring member 46 connects the other end of the first shaft portion 41a in the direction of axis N1 and the other end of the second shaft portion 42a in the direction of axis N2 in a manner that allows for expansion and contraction.

[0046] In this modified example 3, the first roller 41 and the second roller 42 are biased toward each other by a spring member, which is a biasing member. For example, in a natural state where no load other than gravity is applied to the spring member, the distance (gap) between the rollers is equal to or less than the thickness of the leaf spring 2. Therefore, when the leaf spring 2 is positioned between the rollers, the first roller 41 and the second roller 42 each contact the leaf spring 2 and grip it.

[0047] In the modified example 3 described above, similar to the embodiment, the leaf spring 2 that deforms in response to the vibration of the axle 100 has one end locked to the vehicle body (frame 110 in this case) and the other end gripped by the first roller 41 and the second roller 42, and the rollers rotate in response to the displacement of the other end due to deformation. According to this modified example 3, the rotation of each roller suppresses the occurrence of friction between the leaf spring 2 and the retaining member 4A, thereby suppressing a decrease in durability due to friction between the leaf spring and the retaining member, and the generation of abnormal noise.

[0048] Furthermore, according to Modification 3, the spring member changes the distance between the rollers in accordance with the displacement of the leaf spring 2, thereby preventing the leaf spring 2 from receiving excessive load from the rollers and preventing the smooth deformation behavior of the leaf spring from being hindered.

[0049] In Modification Example 3, an example was described in which a spring member is used as a member for adjusting the spacing between rollers. However, the invention is not limited to this, and for example, the spacing between rollers may be electrically controlled by an actuator.

[0050] While embodiments for carrying out the present invention have been described so far, the present invention should not be limited to the embodiments described above. In the embodiments and modifications described above, a configuration in which the axle 100 and the leaf spring 2 are connected via a U-bolt 150 has been described, but a configuration without a U-bolt is also possible, for example, in which the axle 100 and the leaf spring 2 are directly connected. Furthermore, in the embodiments and modifications described above, the leaf spring 2 is positioned above the axle 100, but a configuration in which the leaf spring 2 is positioned below the axle 100 is also possible.

[0051] In addition, in this embodiment, a rotary table supporting the first roller 41 and the second roller 42 may be provided at the rear mounting portion 130, and the first roller 41 and the second roller 42 may be configured to rotate (revolve) around the rotation axis of the rotary table.

[0052] In addition, in this embodiment, a holding member 4 may be provided instead of the locking member 3, and both ends of the leaf spring 2 may be gripped by rollers.

[0053] Furthermore, in this embodiment, one of the rollers may be a non-rotating holding member (corresponding to a pressing member). For example, the second roller 42 may be replaced with a holding member, and the leaf spring 2 may be held by the first roller 41 and the pressing member. In this case, the surface of the holding member that contacts the leaf spring 2 may be curved, or a recess may be formed on the surface that contacts the leaf spring 2.

[0054] Furthermore, in this embodiment, the first roller 41 and the second roller 42 may be supported by a shackle.

[0055] Thus, the present invention may include various embodiments not described herein, and various design modifications can be made without departing from the technical idea specified by the claims.

[0056] As described above, the vehicle suspension system according to the present invention is suitable for suppressing the reduction in durability due to friction between the leaf spring and the retaining member, and for suppressing the generation of abnormal noise. [Explanation of Symbols]

[0057] 1 Suspension system 2 leaf springs 3 Locking member 4, 4A retaining member 41 First Laura 42. Second Laura 43, 44 Laura 41a 1st shaft part 41b First Rotating Section 42a 2nd shaft part 42b Second Rotating Section 43a, 44a shaft part 43b, 44b Rotating part 45 First spring member 46 Second spring member 100 axles 101 Wheels 110 frames 120 Front mounting section 130 Rear mounting section 140 Washer 150 U-bolt 160 Housing 431, 441 Main body 432, 442 1st protrusion 433, 443 2nd protrusion 444 recess

Claims

1. A vehicle suspension system for supporting the axle of a vehicle, Leaf springs and, A locking member to which one end of the leaf spring is locked, A retaining member that holds the other end of the leaf spring, A suspension system equipped with, The locking member and the holding member are attached to the front and rear of the vehicle, respectively. The aforementioned retaining member is A roller that holds the other end of the leaf spring and is rotatable in accordance with the displacement of the other end of the leaf spring, A pressing member facing the roller, It has, The other end of the leaf spring is provided between the roller and the pressing member. A vehicle suspension system characterized by the following:

2. The other end of the leaf spring is held in place by the roller and the retaining member. The vehicle suspension device according to claim 1.

3. A biasing member that biases the roller and the pressing member toward each other, The vehicle suspension device according to claim 1, further comprising the above.

4. The aforementioned retaining member is a roller that can rotate freely in accordance with the displacement of the other end of the leaf spring. The vehicle suspension device according to claim 1.

5. At least one recess is formed on the outer circumferential surface of the roller. The vehicle suspension device according to claim 1.

6. At least one recess is formed on the outer circumferential surface of the roller and the pressing member. The vehicle suspension device according to feature 4.

7. The aforementioned roller, The shaft and, A rotating part is provided on the outer circumference of the shaft portion and is rotatable relative to the shaft portion, It has, The rotating part includes an elastic material, The vehicle suspension device according to claim 1.

8. A projection is formed on at least one end of the roller in the axial direction, projecting in a direction intersecting the axial direction. The vehicle suspension device according to claim 1.

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