Rotary damper type suspension

Abstract

To provide a rotary damper type suspension having excellent mountability and excellent vibration suppressing effect of a vehicle body.SOLUTION: A rotary damper type suspension S includes: an axle 2 to which right and left wheels T are simultaneously or individually connected and which supports a vehicle-body 1a; a case 7 provided on one of the vehicle-body 1a and the axle 2; movable portions 8 that each move the case 7 substantially horizontally between the movable portion and the vehicle-body 1a or the axle 2 in which the case 7 is provided; a rack 5 provided on the case 7 and movable substantially horizontally, and a pinion 6 that meshes with the rack 5; a damper M provided on the pinion 6; an operating-direction changing portion 4 connected to the rack 5 and the member provided with the case 7, of the vehicle-body 1a and the axle 2; and an acting member 3 attached to the other member not provided with the case 7, of the vehicle-body 1a and the axle 2, and connected to the operating-direction changing portion 4.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a suspension that includes a rack and a pinion to which the vertical movement of a vehicle body is transmitted, and that suppresses the sway of the vehicle body by adjusting the rotation of the pinion.

Background Art

[0002] Conventionally, as such a suspension, there is, for example, one shown in Patent Document 1 (see paragraphs

[0006] to

[0008] and FIGS. 1 and 2).

[0003] In this suspension, a first stabilizer and a second stabilizer are distributively connected to the suspensions of the left and right wheels. A first rack having a linear tooth portion is attached to the end of the first stabilizer, and a second rack is attached to the end of the second stabilizer. A first pinion that meshes with both of these first and second racks is provided between the first rack and the second rack, and this pinion can be driven by a first motor.

[0004] That is, with these configurations, the lateral sway (roll) of the vehicle can be suppressed. When lateral sway occurs in the vehicle, the first stabilizer and the second stabilizer move in opposite directions, and the first rack and the second rack attached thereto also move relative to each other. As a result, the first pinion rotates passively. At this time, a predetermined rotation is generated in the first motor, and the relative movement speed of the first rack and the second rack is adjusted to suppress the lateral sway of the vehicle.

[0005] Further, in order to suppress the longitudinal sway (pitch) of the vehicle, a third rack is connected to the first pinion via a rod. A second pinion meshes with this third rack, and the second pinion can be driven by a second motor.

[0006] For example, when the vehicle rides over a convex portion, the first stabilizer and the second stabilizer move in the same direction. At this time, the first rack and the second rack do not move relative to each other, and the first pinion moves up and down. At this time, the third rack connected to the first pinion moves up and down, and the second pinion tries to rotate passively. Here, by driving the second motor and adjusting the rotation speed of the second pinion, the pitch of the vertical sway of the vehicle can be suppressed.

[0007] Thus, according to the conventional configuration, by providing two sets of racks and pinions, it is possible to mechanically and simply configure the stabilizer.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] In the above-described conventional suspension, two sets of racks and pinions are arranged adjacent to each other in the vertical direction in accordance with the operating direction of the suspension. Moreover, the first motor and the second motor, which require a predetermined volume for installation, must be arranged in accordance with the positions of the respective pinions. As a result, in view of the mounting conditions in the lower part of the vehicle, which is restricted by the space volume, the suspension is not necessarily good.

[0010] Thus, the conventional suspension still has points to be improved, such as being greatly restricted in the installation location, and there has been a demand for a suspension that is excellent in mountability and vibration suppression effect of the vehicle body.

Means for Solving the Problems

[0011] (Characteristic Configuration) The characteristic configuration of the rotary damper type suspension according to the present invention is An axle that supports the vehicle body with both the left and right wheels connected simultaneously or individually, a case provided on one of the vehicle body or the axle, a movable part that relatively moves the case along a substantially horizontal direction between the vehicle body or the axle on which the case is provided, a rack provided in the case and movable in a substantially horizontal direction and a pinion that meshes with the rack, a damper provided on the rotation axis of the pinion, an operation direction changing part attached to the member of the vehicle body or the axle on which the case is provided and connected to the rack, an acting member attached to the other of the vehicle body or the axle on which the case is not provided and connected to the operation direction changing part, is provided in this regard.

[0012] (Effect) With this configuration, the acting member and the operation direction changing part convert the vertical movement of the vehicle into a reciprocating movement in the left - right direction and transmit it to the rack, and the movement of the rack is converted into a rotational movement by the pinion. A damper is connected to the pinion and the rotational movement is attenuated. Incidentally, the operation direction changing part and the rack are usually attached symmetrically left and right.

[0013] By converting the vertical movement into a horizontal direction in this way, the mechanism of this configuration facilitates the arrangement in the space between the vehicle and the axle.

[0014] In particular, when the left and right sides of the vehicle body move up and down simultaneously, the left and right racks move in opposite directions and the pinion rotates. As a result, the movement of the rack is suppressed by the rotary damper and the vertical movement of the vehicle is attenuated.

[0015] In addition, when the vehicle sways laterally while running, such as when the racks related to the left and right wheels move in the same direction and the pinion does not rotate, the above damping effect cannot be obtained. However, in the case where the case moves relative to the axle or the movable part of the vehicle body to which it is attached and the vehicle can be tilted, although the pinion does not rotate, the operation direction changing parts on both sides can rotate in opposite directions to each other, and the vehicle body can be tilted appropriately.

[0016] (Characteristic configuration) In the rotary damper type suspension according to the present invention, it is advantageous that the operation direction changing part is a bell crank.

[0017] (Effect) For example, fix a bell crank together with the case to the axle as the operation direction changing part, connect the rack and the bell crank, and connect the rod connected to the vehicle body to the bell crank.

[0018] With this configuration, the operation direction changing part can be configured very simply. For example, when the vehicle is turning, the direction in which the rod on the outer side of the turn rotates the bell crank and the direction in which the rod on the inner side of the turn rotates the bell crank can be made the same. In the case of a bell crank, the design freedom of the operating member connected to it is increased, and the connection of the rack is also easy.

[0019] (Characteristic configuration) In the rotary damper type suspension according to the present invention, a biasing member along the horizontal direction can be provided between the case and the vehicle body or the axle on which the case is provided.

[0020] (Effect) When the vehicle is turning and the vehicle body sways laterally, the racks related to the left and right wheels may move in the same direction and the pinion may not rotate. In such a case, with this configuration, the case can be moved by the biasing member, and the amount of movement of the case is suppressed to suppress the tilt of the vehicle.

[0021] Furthermore, by using a biasing member that suppresses such inclination, it becomes possible to omit the stabilizer provided in a general vehicle, and a rotary damper type suspension with a simpler structure can be obtained.

[0022] (Characteristic configuration) In the rotary damper type suspension according to the present invention, a motor can be provided on the pinion.

[0023] (Effect) With this configuration, the pinion can be positively rotated by driving the motor. Thereby, for example, when the pinion rotates via the operation direction changing portion or the rack due to the vertical movement of the vehicle body, the rotation speed of the pinion can be adjusted by driving the motor with a predetermined torque. That is, positive control of the inclination or vertical movement of the vehicle body becomes possible.

[0024] Also, when the vehicle is stopped, by driving the motor, the left and right bell cranks rotate in opposite directions to each other, enabling positive vehicle height adjustment and improving ride comfort.

Brief description of the drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for carrying out the invention

[0026] 〔First embodiment〕 (Overview) The first embodiment of the rotary damper type suspension S according to the present invention (hereinafter referred to as "suspension S") is shown in FIGS. 1 to 3. FIG. 1 is an explanatory view showing the overall configuration, FIG. 2 is an explanatory view showing the roll suppression mode of the suspension S, and FIG. 3 is an explanatory view showing the pitch suppression mode of the suspension S. These figures show the state of viewing the vehicle 1 from the rear to the front.

[0027] The suspension S of the present embodiment is attached to the vehicle 1 in addition to a normal coil spring or the like that supports the vehicle body 1a on the axle 2 that supports the wheels T, and mainly functions to suppress the sway of the vehicle body 1a during traveling. Although a normal shock absorber is not shown in FIG. 1, a shock absorber may be provided separately.

[0028] As shown in FIG. 1, in the suspension S of the present embodiment, the left and right wheels T are attached to a common axle 2, and a left support portion 21 and a right support portion 22 are provided at a predetermined portion of the axle 2. Among these, in the left support portion 21, for example, a rod-shaped acting member 3 attached to the vehicle body 1a, a bell crank 41 connected to the acting member 3, and a rack 5 having a linear tooth portion connected to the bell crank 41 are provided. The bell crank 41 functions as an operation direction changing portion 4, and the operation of the acting member 3 following the vertical movement of the vehicle body 1a is changed to the horizontal movement of the rack 5 via the bell crank 41. The rack 5 meshes with the pinion 6.

[0029] These members are also provided with the same combination in the right support portion 22. The left rack 51 of the left support portion 21, the right rack 52 of the right support portion 22, and the pinion 6 are housed in a common case 7. The case 7 is attached to the axle 2 via a movable portion 8. Hereinafter, each member will be described.

[0030] The actuating member 3 is a member connected between the vehicle body 1a and the bell crank 41. Its shape can be arbitrary as long as it has a predetermined strength and rigidity and can reliably transmit the vertical movement of the vehicle body 1a to the bell crank 41. For example, when a rod-shaped member is used, it has a predetermined strength and rigidity and good mountability.

[0031] In addition, in response to the lateral sway of the vehicle body 1a, the bell crank 41 rotates via the actuating member 3. At this time, a certain amount of angular change occurs between the vehicle body 1a and the actuating member 3. Although not shown in the figure, in order to allow this, it is advisable to provide a pivot support at the mounting position of the actuating member 3 on the vehicle body 1a that allows a predetermined angle of swing.

[0032] As shown in FIGS. 1 to 3, the bell crank 41 has a pivot point 41a arranged upward and is supported by a pivot shaft extending in the longitudinal direction of the vehicle 1. Thereby, the vertical movement of the actuating member 3 can be changed in the horizontal direction. The horizontal direction here is also the left-right direction of the vehicle 1. In this embodiment, the force transmission direction is changed toward the case 7 located in the center.

[0033] A rack 5 is connected to the bell crank 41. Although not shown, a guide portion for guiding the reciprocating movement of the rack 5 is provided in the case 7. Also, as shown in FIGS. 1(a) and 1(b), a pinion 6 meshes with the rack 5. One pinion 6 is provided in the case 7. When the vehicle 1 is in a stationary state, the substantially central position of the tooth portion of the rack 5 meshes with the pinion 6. Thereby, the stroke of the rack 5 can be sufficiently ensured when the vehicle body 1a moves vertically. In addition, in FIGS. 1 to 3, the height positions of the left rack 51 and the right rack 52 are shown at different levels for easy viewing. However, in reality, both are opposed to each other while sandwiching the pinion 6 at the same height.

[0034] By using the bell crank 41, the operation direction changing section 4 can be configured very simply. By changing the shape of the bell crank 41, the stroke amount of the rack 5 after changing the operation direction can also be set relatively freely. In addition, the degree of freedom in design such as the shape of the acting member 3 connected to the vehicle body 1a is increased, and installation at a predetermined position and connection to the rack 5 are also easy.

[0035] In the present embodiment, the case 7 is shown in a rectangular shape. However, the shape of the case 7 is arbitrary as long as the left rack 51 and the right rack 52 are inserted therein and the pinion 6 meshing with these is pivotally supported. Further, a motor Ma as an example of the damper M is connected to the shaft 61 of the pinion 6. The motor Ma is also fixed to the case 7. This motor Ma functions as a damper that suppresses the horizontal movement of the rack 5.

[0036] The case 7 is connected to the axle 2 via the movable part 8. In the present embodiment, it is held so as to be relatively movable along the left - right direction of the vehicle body 1a. The movable part 8 is formed by using a biasing member 9 between the axle 2 and the case 7. Left support parts 21 and right support parts 22 are formed on the axle 2, and the case 7 is arranged at a position sandwiched between these. As the biasing member 9, for example, a coil spring is used and is interposed between the left support part 21 or the right support part 22 and the case 7.

[0037] The movable part 8 is composed of, for example, an inner cylindrical member 8a and an outer cylindrical member 8b that can be inserted into each other, and a coil spring is inserted inside this. The inner cylindrical member 8a and the outer cylindrical member 8b are stretchable with respect to each other, but are configured so that the deviation in the axial direction of each other is small. That is, the case 7 is configured not to move up and down with respect to the left support part 21 and the right support part 22, and the posture of the case 7 does not change excessively.

[0038] (Roll suppression) These racks 5 and pinions 6 can suppress the left and right tilting of the vehicle body 1a. Fig. 2 shows the state during right-turn driving. The vehicle body 1a tilts to the left, the left acting member 31 descends, and the right acting member 32 ascends. As a result, the left rack 51 is pushed toward the center side of the vehicle body 1a, and the right rack 52 is pulled out in the right direction of the vehicle body 1a.

[0039] If the moving amounts of the left rack 51 and the right rack 52 are the same, the pinion 6 does not rotate. Therefore, as the rack 5 moves, the case 7 is forced to move rightward. The case 7 is biased and held in the neutral position with respect to the axle 2 by a left coil spring 91 and a right coil spring 92 as biasing members 9. Thus, when the case 7 tends to be displaced to either the left or the right, the left and right coil springs 91, 92 expand and contract, and the case 7 stops at a balanced position. The elastic deformation of the left and right coil springs 91, 92 at this time restricts the movement of the left and right acting members 31, 32 and the left and right racks 51, 52, suppressing the roll of the vehicle body 1a.

[0040] In addition, by using the biasing member 9 that suppresses roll in this way, it is possible to omit the stabilizer provided in a general vehicle 1, and a suspension S with a simpler structure can be obtained.

[0041] (Suppression of pitching) These racks 5 and pinions 6 can also suppress the vertical movement of the vehicle body 1a. Fig. 3 shows the state where the vehicle body 1a sinks when driving on an uneven road surface. The left acting member 31 and the right acting member 32 descend, and the left rack 51 and the right rack 52 are pushed toward the pinion 6. As a result, the pinion 6 rotates.

[0042] The vehicle body 1a is equipped with various sensors such as a vehicle height sensor and a G sensor (not shown in the figure), and the acceleration of the vertical movement of the vehicle body 1a and the like can be calculated from the signals obtained therefrom. By driving the motor Ma based on the calculated value, further movement of the left rack 51 and the right rack 52 can be restricted, and the sinking of the vehicle body 1a can be suppressed.

[0043] Furthermore, the left acting member 31 and the right acting member 32 do not necessarily move up and down by the same amount, and lateral sway is often mixed. In that case, the moving amounts of the left and right racks 51 and 52 change, and lateral movement of the case 7 occurs. Since this movement is resisted by the left coil spring 91 and the right coil spring 92, lateral sway of the vehicle body 1a is also suppressed at the same time.

[0044] In addition, by driving the motor Ma while the vehicle 1 is stopped, the left and right bell cranks 411 and 412 can be positively rotated in opposite directions to adjust the vehicle height. Also, it is possible to function as an active suspension or to adjust the vehicle height for convenience during boarding and alighting.

[0045] As described above, by adopting a configuration that converts the vertical movement of the acting member 3 accompanying the vertical movement of the vehicle body 1a into a horizontal direction, it becomes easy to arrange the rack 5, the pinion 6, etc. in the narrow space between the vehicle body 1a and the axle 2. Therefore, the vibration suppressing effect of the vehicle body 1a can be surely exhibited, and a suspension S with excellent mountability can be obtained.

[0046] 〔Second Embodiment〕 The second embodiment of the present invention is shown in FIG. 4. Here, the biasing member 9 is provided not across the axle 2 and the case 7 but between the left and right bell cranks 411, 412 and the left and right racks 51, 52.

[0047] For this purpose, the case 7 is fixed to the axle 2, and the case 7 is further provided with left and right arm portions 101 and 102 that support the left and right bell cranks 411 and 412. Both ends of the left and right coil springs 93 and 94 as the biasing member 9 are connected to the bell crank 41 and the rack 5. As a result, the coil spring exerts a biasing force in both pushing and pulling directions.

[0048] When the vehicle 1 makes a turning motion and the vehicle body 1a sways laterally, as in the first embodiment, the left and right racks 51, 52 may move in the same direction and the pinion 6 may not rotate. For example, when the vehicle makes a right-turning motion and the left side of the vehicle body 1a descends while the right side ascends, the left coil spring 93 contracts and the right coil spring 94 extends while the operations of the left and right bell cranks 411, 412 are suppressed. Thereby, the lateral sway of the vehicle body 1a is suppressed.

[0049] On the other hand, when the vehicle 1 travels on a rough road surface and the vehicle body 1a sinks, as in the first embodiment, the left and right racks 51, 52 move in the inner direction and the pinion 6 rotates. At this time, by driving the motor Ma, the movement of the left and right racks 51, 52 can be restricted, and the vertical sway of the vehicle body 1a can be suppressed.

[0050] In addition, when the left and right racks 51, 52 try to move when lateral sway and vertical sway occur, the left and right coil springs 93, 94 expand and contract slightly. The elastic force generated by this expansion and contraction naturally contributes to the suppression of the vehicle body 1a. Therefore, particularly when driving the pinion 6 by the motor Ma to suppress vertical sway, it is advisable to determine the driving torque and the like while considering the elastic force that has already occurred in the left and right coil springs 93, 94.

[0051] With this configuration, the space can be saved for the members, such as the case 7 being directly attached to the axle 2, and a suspension S that is simple and has excellent mountability can be obtained without the need to provide a special mechanism for attachment.

[0052] 〔Third Embodiment〕 The third embodiment of the present invention is shown in FIG. 5. Here, the attachment modes of the bell crank 41 and the case 7 are set contrary to those in the first embodiment and the like.

[0053] Here, left and right support portions 23 and 24 for attaching left and right bell cranks 411 and 412 are provided on the vehicle body 1a. Further, the case 7 is attached to the left and right support portions 23 and 24. At this time, the same inner cylindrical member 8a, outer cylindrical member 8b, and left and right coil springs 91 and 92 as those in the first embodiment are used. On the other hand, left and right actuating members 33 and 34 are provided on the axle 2 and connected to the left and right bell cranks 411 and 412.

[0054] In the case of this configuration, the mechanism for suppressing roll and pitch is the same as that of the first embodiment. However, in this configuration, since the case 7 is provided on the vehicle body 1a, the so-called unsprung weight is reduced. As a result, a suspension with improved ride comfort can be obtained, such as the wheels T being more likely to follow the unevenness of the road surface.

[0055] 〔Other Embodiments〕 As a damping mechanism for the pinion 6, an elastic member such as a coil spring can be attached instead of the motor Ma. By utilizing the elastic force generated when the coil spring is wound up or released, the rotation of the pinion 6 can be suppressed only by a mechanical structure. Therefore, a special electrical mechanism and control circuit are not required, and a simpler suspension S can be obtained.

[0056] In any of the above embodiments, the bell crank 41 is used as the operation direction changing portion 4. Instead of this, the rack 5 can be operated by using a flexible cable or the like. For example, by connecting an operating cable composed of an outer cable and an inner cable between the vehicle body 1a and the rack 5, a suspension S with more space-saving and excellent mountability can be obtained.

Industrial Applicability

[0057] The rotary damper type suspension includes a rack and a pinion to which the up and down movement of the vehicle body is transmitted, and can be widely used as a suspension that suppresses the sway of the vehicle body by adjusting the rotation of the pinion.

Explanation of Reference Numerals

[0058] 1a Vehicle body 2 Axle 3 Actuating member 4 Motion direction changing part 41 Bell crank 5 Rack 6 Pinion 7 Case 8 Movable part 9 Biasing member M Damper Ma Motor S Rotary damper type suspension T Wheel

Claims

1. An axle in which both the left and right wheels are connected simultaneously or individually to support the vehicle body, a case provided on one of the vehicle body or the axle, a movable part that relatively moves the case substantially along a horizontal direction between the vehicle body or the axle on which the case is provided, a rack provided in the case and movable in a substantially horizontal direction, and a pinion that meshes with the rack, a damper provided on the rotation axis of the pinion, an operation direction changing part attached to the member of the vehicle body or the axle on which the case is provided and connected to the rack, an acting member attached to the other of the vehicle body or the axle on which the case is not provided and connected to the operation direction changing part, and a rotary damper type suspension provided with these.

2. The rotary damper type suspension according to Claim 1, wherein the operation direction changing part is a bell crank.

3. The rotary damper type suspension according to Claim 2, further comprising a biasing member along the horizontal direction between the case and the vehicle body or the axle on which the case is provided.

4. The rotary damper type suspension according to any one of Claims 1 to 3, wherein a motor is provided on the pinion.

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