Front wheel section for a vehicle equipped with two front steering wheels and a vehicle equipped with the said front wheel section
The front wheel section with an inclined four-bar linkage and perpendicular suspension links addresses the challenges of driving comfort and maintenance costs in tilting three-wheeled vehicles, achieving reduced friction and wear, and improved maneuverability and stability.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- PIAGGIO & C SPA
- Filing Date
- 2019-12-06
- Publication Date
- 2026-05-21
AI Technical Summary
Existing tilting three-wheeled vehicles face challenges in providing optimal driving comfort and safety due to the design of their suspension and steering systems, which often result in increased friction and wear, and require significant space between the front wheels.
A front wheel section featuring an inclined four-bar linkage and two suspension units for each front wheel, where the four-bar suspension links are perpendicular to the central plane of the vehicle, allowing for reduced friction and wear, and the shock absorbers are constrained at two points on the linkage, changing length with movement, enabling better driving comfort and reduced production and maintenance costs.
The solution provides improved driving comfort and reduced maintenance costs by minimizing friction and wear, while allowing for closer wheel spacing, enhancing the vehicle's maneuverability and stability.
Smart Images
Figure 0007863417000001 
Figure 0007863417000002 
Figure 0007863417000003
Abstract
Description
Technical Field
[0006] , ,
[0005] , ,
[0007] ,
[0001] The present invention relates to the field of tilting vehicles, i.e., the field of vehicles that perform tilting movements around a central plane extending longitudinally along the vehicle. A tilting vehicle is typically a three-wheeled vehicle having two front steering wheels and one rear driving wheel. By means of the tilting movement, the vehicle can be tilted during its operation, for example, when driving through a curve.
Background Art
[0002] In the field of vehicles, there has been an increasing supply of vehicles that combine the handleability of a motorcycle with the stability of a four-wheeled vehicle.
[0003] Examples of these models include three-wheeled vehicles having two front steering wheels and one rear driving wheel and four-wheeled vehicles commonly called quad bikes (buggies).
[0004] More specifically, the above-mentioned three-wheeled vehicle rolls, i.e., tilts, laterally while performing a rocking movement, i.e., a tilting movement, about an axis substantially directed in the traveling direction. These three-wheeled vehicles also include an engine connected to the rear driving wheel, with a pair of front wheels controlling the direction of the vehicle while supplying torque to the rear driving wheel to obtain traction.
[0005] With this solution, a vehicle having two front driving wheels has higher stability compared to a two-wheeled vehicle due to the double support of the front wheels on the ground, similar to a motor vehicle.
[0006] The front wheels are kinematically connected to each other using a mechanism that can substantially synchronize the tilting and steering of the front wheels, for example, by interposing a four-bar link that connects the front wheels to the front-wheel frame. In addition, these vehicles are provided with two independent suspensions, one for each front wheel. Each suspension is provided with an elastic body (spring) and a viscous body (shock absorber).
[0007] Therefore, the purpose of a tilting three-wheeled vehicle is to simultaneously guarantee the user the maneuverability of a two-wheeled vehicle and the stability and safety of a four-wheeled vehicle.
[0008] This type of tilting three-wheeled vehicle is disclosed, for example, in International Publications WO2017 / 115294, WO2017 / 115295, WO2017 / 115296, WO2017 / 115297, and WO2018 / 104906.
[0009] The design of the suspension and steering systems in this type of vehicle is a crucial aspect, as they must provide driving comfort and safety.
[0010] Therefore, continuous improvement of suspension and steering systems for inclined vehicles with two front steering wheels is necessary. [Overview of the project]
[0011] According to a first aspect, the present invention relates to a front wheel section for a vehicle comprising an inclined four-bar linkage and two suspension units for two front wheels. The inclined four-bar linkage comprises a first crossbar, a second crossbar, a first upright section, and a second upright section, which are hinged to each other. The first and second crossbars extend laterally with respect to the center plane of the vehicle, that is, they extend in the left-right direction. Each of the first and second upright sections is hinged to the first and second crossbars at two points spaced apart from each other. Each of the first and second crossbars is hinged at each intermediate point to the front wheel section frame or an element rigidly connected to the front wheel section frame, such as a steering sleeve.
[0012] Each suspension unit is associated with each upright section. Each suspension unit includes a wheel support for each front wheel of the vehicle. The wheel support defines the axis of rotation for each wheel. Each suspension unit further includes a support arm rotatably connected to each upright section so as to rotate about the steering axis.
[0013] Each suspension unit also comprises a four-bar suspension link. In some embodiments, a support arm, or a part thereof, is one element of the four-bar suspension link, and a wheel support is a second element of the four-bar suspension link.
[0014] In the embodiments disclosed herein, each four-bar suspension link also has a pair of cranks connecting the wheel support and the support arm. In particular, each four-bar link comprises a first crank hinged to the wheel support and the support arm, and a second crank hinged to the wheel support and the support arm. The first crank, the second crank, the wheel support and the support arm of each suspension unit are hinged to each other to form each four-bar suspension link, each four-bar suspension link essentially extends along a central plane substantially perpendicular to the central plane of each front steering wheel. In other words, the hinge axes to which the cranks are connected to the support arm and the wheel support, i.e., the rotational axes of the components of the four-bar suspension link that are parallel to each other, are perpendicular to the plane containing the rotational axis of each front steering wheel and are parallel to the central plane of each front steering wheel.
[0015] Generally, the four-bar suspension links of each front steering wheel are perpendicular to the center plane of each front steering wheel. The axes of the interconnections of the two components of the four-bar suspension links are perpendicular to the plane containing the rotation axis of each front steering wheel.
[0016] Each suspension unit is further equipped with a shock absorber constrained at two points on a four-bar suspension link. The distance between these two points changes when the four-bar suspension link moves. As a result, for example, when the four-bar link moves due to the vertical movement of each front steering wheel, the length of the shock absorber changes accordingly.
[0017] This type of front wheel section allows the contact point between the ground and the wheel to move in a linear motion relative to the vehicle in its projection onto the vehicle's central plane, rather than the rotational-translational motion that occurs in suspension systems disclosed in the following literature, for example. International Publication W02018 / 104906 discloses that the four-bar suspension links of each steering wheel are parallel to the wheel's central plane and therefore have a hinge axis parallel to the rotation axis of each front steering wheel. The suspension thus obtained functions equivalently to a fork suspension but with significantly reduced costs and added kinematic advantages. In fact, in a fork suspension, it is necessary to provide mutually movable elements between them, i.e., sliding supports, i.e., supports for translational motion, whereas in the four-bar suspension links described herein, the vertical motion of the wheels causes the components of the four-bar suspension links to rotate around a rotational support rather than a translational support. Thus, a system with less friction is obtained, adapted to achieve better driving comfort, less wear, and reduced production and maintenance costs.
[0018] Furthermore, in some embodiments, the front wheel section described above offers additional advantages compared to the configuration of the prior art. In particular, the four-bar suspension linkage, which unfolds perpendicular to the center plane of each front steering wheel, allows for control of the camber angle of each front steering wheel, and the camber angle can be changed during suspension compression, i.e., during shock absorber compression, as occurs in high-performance vehicles and racing cars.
[0019] Furthermore, the four-bar suspension linkage disclosed herein ensures that, during the rotation of the steering wheel around each steering axis, the plane on which the four-bar linkage is located and the plane on which the wheel is located are always oriented at a 90° angle to the axis.
[0020] According to another embodiment, the present invention relates to an automobile comprising at least one rear drive wheel, two front steering wheels, and the aforementioned front wheel section, wherein two wheel support sections support the two steering wheels of the vehicle.
[0021] Also disclosed is a vehicle having a front wheel section and a pair of front steering wheels connected to the front wheel section by an inclined four-bar linkage. Furthermore, the vehicle is provided with a four-bar suspension linkage and shock absorbers for each front steering wheel. Each shock absorber is constrained at two points by two components of the four-bar suspension linkage and is configured to change length in accordance with the movement of the four-bar suspension linkage. Each four-bar suspension linkage extends along a plane perpendicular to the plane in which each front steering wheel is located. In practice, the axes of the mutual articulation links between the two components of the four-bar suspension linkage are configured to be perpendicular to the plane containing the rotation axis of each front steering wheel.
[0022] Advantageously, a wheel support arm, which is one of the four elements of each four-bar suspension link, can form an upright portion extending toward the inclined four-bar link. In this way, the support arm of each front steering wheel kinematically connects the wheel to the four-bar link, and advantageously, the inclined four-bar link can be positioned at a higher level than the two four-bar suspension links. In this way, the suspension members in the region formed between the two front steering wheels are less bulky than those disclosed, for example, in International Publication W02018 / 104906. This eliminates the need to leave space for the inclined four-bar link between the front wheels, making it possible to position the two front wheels closer together, i.e., closer to the center plane of the vehicle.
[0023] In possible embodiments of the front wheel section and vehicle according to the present invention, the shock absorber is interposed between the support arm and the wheel support section.
[0024] For example, the wheel support may have a body to which the first crank and the second crank are joined at two points spaced apart from each other. The body may have an attachment that extends beyond the hinge point of the first crank and the hinge point of the second crank to which a shock absorber is joined.
[0025] In the above-described front wheel part and / or other embodiments of the vehicle, the shock absorber may be interposed between the support arm and an auxiliary rocker that is joined at two points to the first crank and the second crank. The auxiliary rocker may advantageously be arranged at an intermediate position between the wheel support part and the support arm. With this arrangement, the load on the shock absorber can be distributed to both cranks. Further, the constraint point between the shock absorber and the auxiliary rocker moves along a different trajectory than the trajectory along which the shock absorber moves when it is directly constrained to one crank of the suspension four-bar link. In this way, depending on the mechanical sizes of the various components of the suspension, the shock absorber can be arranged more freely, and a sufficiently wide stroke of the shock absorber can be obtained during the up-and-down movement of each wheel.
[0026] Each support arm of the two front steering wheels may have a connection element for connecting to the steering system. For example, the two support arms are connected to a steering rod that is connected to a steering tube rotatably accommodated in a steering sleeve integrally provided on the front wheel part frame.
[0027] In order to achieve a particularly compact arrangement, the front wheel part may have the upright part of an inclined four-bar link that is adapted to form each housing for rotatably accommodating each support arm of each suspension unit. The present invention will be better understood in accordance with the following description and the accompanying drawings, which illustrate exemplary and non-limiting embodiments of the present invention.
Brief Description of the Drawings
[0028] [Figure 1] It is a side view of a three-wheeled vehicle according to the present invention. [Figure 2] It is a plan view taken along line II-II of FIG. 1. [Figure 3] It is a front view taken along line III-III of FIGS. 1 and 2. [Figure 4] It is a perspective view of the front part of the vehicle shown in FIGS. 1, 2, and 3. [Figure 5A] It is an enlarged front view in partial section of an embodiment of the suspension of the front wheel. [Figure 5B] This is a partially cut and enlarged front view of one embodiment of the front wheel suspension. [Figure 6A] This is a partially cut and enlarged front view of another embodiment of the front wheel suspension. [Figure 6B] This is a partially cut and enlarged front view of another embodiment of the front wheel suspension. [Figure 7] This is a view of line VII-VII in Figure 6A. [Figure 8] This is a front view taken along line VIII-VIII in Figure 7. [Figure 9] This is a partial section view, similar to Figures 5A and 6A, of yet another embodiment of the suspension unit. [Figure 10] This is a view of line XX in Figure 9. [Figure 11] Figure 10 is a view along the line XI-XI. [Figure 12] This is a kinematic diagram of one embodiment of the front wheel section of a vehicle. [Figure 13] This is a kinematic diagram of another embodiment of the front wheel section of a vehicle. [Modes for carrying out the invention]
[0029] The attached drawings show an embodiment of the present invention applied to a three-wheeled vehicle, i.e., a vehicle having one rear drive wheel. However, as described above, the front wheel portion of the present invention can also be applied to four-wheeled vehicles such as so-called quad bikes.
[0030] To better understand the novel features of various embodiments of the suspension and steering system according to the present invention, Figures 1 to 11 show actual embodiments thereof, and Figures 12 and 13 show kinematic diagrams of the components that define the suspension and the members that enable the tilting motion of the vehicle and the steering motion of the front wheels.
[0031] Vehicle 1 has a front wheel section indicated by reference numeral 2, i.e., a front wheel section, to which two front steering wheels 3' and 3'' are associated. In the following description, components, groups, or elements that are symmetrical with respect to the central plane M of Vehicle 1 are indicated by the same reference numeral, followed by a comma (') for elements on one side of the central plane M, for example, the element to the left of the driver, and a comma ('') for elements on the other side of the central plane M, for example, the element to the right of the driver. When a reference numeral used without a comma ('') and (') to indicate the elements on the right and left sides of the central plane is used, it means that the elements on the right or left side can be referred to without distinction.
[0032] Vehicle 1 also includes an engine 5 and a rear drive wheel 7 equipped with a transmission member (details not shown).
[0033] The front wheel section 2 is equipped with a front wheel section frame 9, and a steering sleeve 11 is integrally provided on the front wheel section 9. A steering tube 13 is rotatably housed within the steering sleeve 11 and is torsionally coupled to a handlebar 15. As shown in the kinematic diagrams of Figures 12 and 13, the driver applies steering to the front steering wheels 3', 3'' via this handlebar 15.
[0034] As will be described in more detail below, the front wheel section 2 of vehicle 1 is equipped with a tilting four-bar linkage 21 to which the wheels 3',3'' are connected. The tilting four-bar linkage allows the vehicle to tilt when traveling around a curve. Each wheel 3',3'' is connected to the tilting four-bar linkage 21 by support arms 23',23'', which are part of each suspension four-bar linkage 25',25''. Each suspension four-bar linkage 25',25'' is equipped with shock absorbers 26',26''. Each suspension four-bar linkage 25',25'' with each shock absorber 26',26'' is part of a suspension unit for wheels 3',3'', indicated collectively by reference numeral 28',28''. Each suspension unit 28',28'' is connected to the tilting four-bar linkage 21 via support arms 23',23'', which constitute an upright extension of one of the elements of the suspension four-bar linkage 25',25''.
[0035] Each support arm 23', 23'' is connected to a tilting four-bar link 21 so as to be rotatable around each steering axis 27', 27'' controlled by the handlebar 15. For this purpose, each support arm 23', 23'' is provided with connecting members 24', 24'' for connecting the support arms 23', 23'' to a steering bar 29, which is part of a steering link that connects the support arms 23', 23'' to the steering pipe 13.
[0036] More specifically, the inclined four-bar link 21 comprises a first crossbar 31 (upper crossbar) and a second crossbar 33 (lower crossbar). Each crossbar 31, 33 is joined to the front wheel frame 9, more precisely to the steering sleeve 11 in the illustrated example, at a center point indicated by reference numeral 31A for crossbar 31 and reference numeral 33A for crossbar 33. In this way, the crossbars 31 and 33 can rotate about inclination axes defined by hinges connecting the crossbars to the front wheel frame. As shown in Figure 3, when the inclination angle of the vehicle 1 is equal to zero, the inclination axes are substantially parallel to each other and lie on the central plane M of the vehicle 1.
[0037] Furthermore, the inclined four-bar link 21 includes two upright sections 35' and 35''. More specifically, the upper crossbar 31 is joined to the upright section 35' at the position indicated by reference numeral 32' and to the upright section 35'' at the position indicated by reference numeral 32''. The lower crossbar 33 is joined to the upright section 35' at the position indicated by reference numeral 34' and to the upright section 35'' at the position indicated by reference numeral 34''. In Figure 7, reference numerals 32X and 34X indicate the axes of the joints connecting the upright section 35 and the crossbars 31 and 33.
[0038] In the illustrated embodiment, the upright sections 35', 35'' have a cylindrical housing-like shape, and the upper parts of each support arm 23', 23'' are supported inside. Rotating bearings or bushings (not shown) allow the support arms 23', 23'' to rotate inside the housing formed by each upright section 35', 35''.
[0039] Each support arm 23', 23'' extends downward from the inclined four-bar link 21, where each suspension four-bar link 25', 25'' is formed. Therefore, the inclined four-bar link 21 is positioned higher than the two suspension four-bar links 25', 25'' and each wheel 3', 3''.
[0040] Each four-bar suspension link 25',25'' is formed by four elements, one of which is the corresponding support arm 23',23'', which in fact constitutes the rocker of the four-bar suspension link 25',25'' and extends upward in an upright position toward the inclined four-bar link. Wheel support sections 41',41'' are connected to each of the two support arms 23',23''.
[0041] Each wheel support 41', 41'' defines the rotation axis 43', 43'' of each wheel 3', 3''. Reference numerals 45', 45'' indicate the rotation axis of each wheel 3', 3'' (see Figures 5A, 5B; 6A, 6B in particular).
[0042] Each wheel support section 41', 41'' is connected to each support arm 23', 23'' by a pair of cranks 42A', 42B' and 42A'', 42B''. Reference numerals 47A', 47B' indicate articulated hinges of the cranks 42A', 42B' to the support arms 23'', and reference numerals 47A'', 47B'' indicate articulated hinges of the cranks 42A'', 42B'' to the support arms 23''. In Figure 7, reference numerals 47X and 47Y indicate the rotational axes of the articulated hinges 47A'', 47B'' of the cranks 42A'', 42B'' to the support sections 23''. Similarly, reference numerals 48A' and 48B' indicate articulated hinges of cranks 42A' and 42B' with respect to the wheel support 41', and reference numerals 48A'', and 48B'' indicate articulated hinges of cranks 42A'', and 42B'' with respect to the wheel support 41''. The axes of the articulated hinges 47A, 47B, 48A, and 48B of the four elements 23, 41, 42A, and 42B of each four-bar suspension link 25 are parallel to each other and perpendicular to the plane containing the rotation axes 43', and 43'' of the wheels 3' and 3''.
[0043] Each four-bar suspension link 25', 25'' extends along a plane parallel to the rotation axis 43', 43'' of each wheel. Therefore, the plane on which each four-bar suspension link 25', 25'' is located is perpendicular to the plane on which each front steering wheel 3', 3'' is located. In this specification, "plane on which one or more members are located" means the central plane through which the elements of the members pass. Therefore, in the case of a four-bar link such as the four-bar suspension links 25', 25'', the plane on which the four-bar link is located is the central plane of the cranks 42A, 42B, and the central plane of a portion of the wheel support 41 and a portion of the suspension arm 23 to which the cranks 42A, 42B are joined. Note that in the simplified kinematic diagrams of Figures 12 and 13, the plane on which the simplified four-bar suspension link 25 is located is approximately the same as the plane in the drawing, and the plane on which the wheel 3 is located is perpendicular to the plane in the drawing. In this embodiment, as shown in Figure 7, for example, the plane on which the four-bar suspension link 25 is located is inclined, for example, about 10° backward with respect to the vertical plane. The center plane of the four-bar suspension link 25 or the plane on which it is located is indicated by the reference numeral M25 in Figure 7.
[0044] The plane on which wheel 3 is located is the same wheel center plane, denoted by symbols 3A' and 3A'', as can be seen particularly in Figures 5A, 5B and 6A, 6B.
[0045] Each four-bar suspension link 25', 25'' is essentially positioned such that its central plane, i.e., the plane on which the four-bar links 25', 25'' are located, is substantially perpendicular to the plane on which each front wheel 3', 3'' is located.
[0046] In practical embodiments, each crank 42A', 42A'', 42B', and 42B'' can be doubled to provide greater mechanical strength, as seen in Figure 3, and especially in Figure 7. In Figures 5A, 5B, and 6A, 6B, only one component of each double crank is shown; more precisely, in each figure, the component located behind the shock absorbers 26', 26'' is shown, while the corresponding component located in front of the shock absorbers is omitted to better illustrate the layout of the shock absorbers 26', 26''. In other embodiments, each crank may be U-shaped or H-shaped, i.e., doubled, but may be made of a single member rather than consisting of two components hinged to a common shaft.
[0047] Each wheel support 41', 41'' can be adapted to support not only the rotational axes 45', 45'' of each wheel 3', 3'' but also the brake units 51', 51'' that act on the brake discs 53', 53''.
[0048] Each shock absorber 26', 26'' may generally have an elastic element, such as a helical spring 61', 61'', and a damping element 63', 63''. In the illustrated embodiment, each elastic element 61 and each damping element 63 are arranged coaxially with each other, but this is not mandatory. For example, the damping element and the elastic element may be arranged parallel to each other and adjacent to each other.
[0049] Ideally, each shock absorber 26', 26'' is constrained, either directly or indirectly, at two different points on each suspension four-bar link 25', 25'', preferably at its end. More precisely, in order to enable the correct operation of the suspension four-bar links 25', 25'' and the corresponding shock absorbers 26', 26'', the shock absorbers 26', 26'' are constrained at two points where their relative distance changes as each four-bar link deforms due to the vertical movement of the wheel. In the embodiments shown in Figures 1, 2, 3, 4, 6A, 6B, 7, 8, and 12, each shock absorber 26', 26'' is hinged at its top, where points 26A', 26A'' are located, to support arms 23', 23'', and at its bottom, where points 26B', 26B'' are located, to accessories or extensions 41A', 41A'' extending from the main body of the corresponding wheel support 41', 41'' to which cranks 42A', 42B', and 42A'', 42B'' are joined.
[0050] When the four-bar linkage 25',25'' deforms, the two hinge points 26A',26B',26A'',26B'' of each shock absorber 26',26'' move toward or away from each other (resulting in the shock absorber becoming shorter or longer).
[0051] The above-described method of restraining the elements of the shock absorber 26 and the suspension four-bar link 25',25'' is not the only possible method. In the embodiments of Figures 5A, 5B, and 13, each shock absorber 26 is hinged to the corresponding support arm 23',23'' at the position indicated by reference numeral 26A',26A'', substantially similar to the embodiments of Figures 1-4, 6A, 6B, 7, 8, and 12, except at the bottom, each shock absorber 26',26'' is hinged to the auxiliary rocker 71',71'' at the position indicated by reference numeral 26B',26B'', the auxiliary rocker 71',71'' has accessories 71A',71A'', which are hinged to the cranks 42A',42B' and 42A'',42B'' respectively. Preferably, the auxiliary rockers 71', 71'' (see Figures 5A, 5B in particular) are positioned at an intermediate location between the wheel support sections 41', 41'' and the support arms 23', 23''.
[0052] In a particularly advantageous embodiment, as shown in the accompanying drawings, each support arm 23', 23'' has a lower curved portion displaced toward the centerline of the vehicle 1 with respect to the corresponding steering axis 27', 27'' so as to have more space for mounting shock absorbers 26', 26'' while maintaining a reduced distance between the two front steering wheels 3', 3''. The two support arms 23', 23'' spread apart upward and are coupled to the upright portions 35', 35'' of the inclined four-bar link 21.
[0053] Figures 9, 10, and 11 show a third embodiment relating to the right suspension unit 28''. The same reference numerals indicate the same or equivalent members as those shown in the previous figures and already described. These members will not be described again. Figure 9 is a partial cross-sectional view of the suspension four-bar link 25'' following the extension plane, i.e., a substantially perpendicular plane parallel to the plane on which the suspension four-bar link 25'' lies, similar to Figure 5A. Figure 10 is a side view of the vehicle 1, i.e., a view from the center plane MM of the vehicle 1, as seen from arrow XX in Figure 9, and Figure 11 is a front view of the suspension unit 28'' as seen from XI-XI in Figure 10.
[0054] The embodiments in Figures 9 to 11 are kinematically equivalent to the embodiments in Figures 5A, 5B, and 13 because they include an auxiliary rocker 71''. The bottom of the shock absorber 26'' is articulated with respect to the auxiliary rocker 71'' at the position indicated by reference numeral 71A''. The difference between the embodiments in Figures 9, 10, and 11 and those in Figures 5A and 5B is the shape of the auxiliary rocker 71'', which in this case does not protrude below the four-bar suspension link 25''. More specifically, the rocker 71'' is completely housed within the volume defined by the cranks 42A'' and 42B''. This increases the distance of the shock absorber 26'' from the ground, concealing its lower end and resulting in aesthetic and functional advantages.
[0055] Furthermore, in the embodiments shown in Figures 1 to 8, the hinge axes 32X and 34X are parallel to each other and parallel to the hinge axes 47X and 47Y (see Figure 7 in particular), but in the embodiments shown in Figures 9 to 11, as seen particularly in Figure 10, the axes 47X and 47Y are not parallel to the axes 32X and 34X, but are inclined to them, for example, by about 5°.
Claims
1. Front wheel section (2) for a vehicle, An inclined four-bar link (21) having a first crossbar (31), a second crossbar (33), a first side section (35'), and a second side section (35'') that are hinged together, A first suspension unit (28') associated with the first side portion (35'') and a second suspension unit (28'') associated with the second side portion (35'') Equipped with, Each of the first suspension unit (28') and the second suspension unit (28'') is, A wheel support (41', 41'') for a vehicle wheel (3', 3''), comprising a wheel support (41', 41'') that defines the axis of rotation (43', 43'') of the wheel (3', 3''), Support arms (23', 23'') are rotatably connected to each side section (35', 35'') so as to rotate around the steering axis (27', 27''), First cranks (42A', 42A'') connected to the wheel support (41', 41'') and support arms (23', 23'') via each first joint axis (47A', 48A'; 47A'', 48A'') and second cranks (42B', 42B'') connected to the wheel support (41', 41'') and support arms (23', 23'') via each second joint axis (47B', 48B'; 47B'', 48B''), wherein the first cranks (42A', 42A''), second cranks (42B', 42B''), wheel support (41', 41'') and support arms (23', 23'') are connected to a four-bar suspension ring. The first and second cranks form a (25', 25'') such that, with each suspension four-bar link (25, 25') and each wheel support (41', 41'') in any state around each steering axis (27, 27'), the articulated axes (47A, 47B, 48A, 48B) of the first crank (42A', 42A''), second crank (42B', 42B''), wheel support (41', 41''), and support arm (23', 23'') of each suspension four-bar link (25, 25') are parallel to each other and perpendicular to the plane containing the rotation axis (43', 43'') of each wheel (3', 3''), A shock absorber (26', 26'') is constrained at two points (26A', 26A''; 26B', 26B'') of a four-bar suspension link (25', 25''), and the distance between these two points changes when the four-bar suspension link (25', 25'') moves and the length of the shock absorber changes. It is equipped with, The two side sections (35', 35'') of the inclined four-bar link (21) each form a housing, and within each housing, the support arms (23', 23'') of each suspension unit (28', 28'') are rotatably supported. The plane is a plane parallel to the longitudinal direction of the shock absorber. A front wheel section for a vehicle characterized by the following features.
2. The shock absorber (26', 26'') is connected to the support arm (23', 23'') and the wheel support (41', 41''). The front wheel section according to feature 1.
3. Each wheel support (41', 41'') has a body to which each first crank (42A', 42A'') and each second crank (42B', 42B'') are joined at the respective first joint connecting axes (48A', 48A'') and the respective second joint connecting axes (48B', 48B'') which are spaced apart from each other. The main body extends downward beyond the respective first joint axis lines (48A', 48A'') and the respective second joint axis lines (48B', 48B'') to form attachments (41A', 41A'') to which the shock absorbers (26', 26'') are joined. The front wheel portion according to feature 2.
4. The shock absorbers (26', 26'') are connected to auxiliary rockers (71', 71'') and support arms (23', 23''), which are joined at one point to the first crank (42A', 42A'') and at the second crank (42B', 42B''). The front wheel section according to feature 1.
5. The first point where the auxiliary rocker (71', 71'') is joined to the first crank (42A', 42A'') is positioned between the first joint axis lines (47A', 47A''; 48A', 48A'') to which the first crank (42A', 42A'') is connected to the support arm (23', 23'') and the wheel support portion (41', 41''), The second point where the auxiliary rocker (71', 71'') is joined to the second crank (42B', 42B'') is located between the second joint axis lines (47B', 47B''; 48B', 48B'') where the second crank (42B', 42B'') is connected to the support arm (23', 23'') and the wheel support portion (41', 41''). The front wheel section according to feature 4.
6. The wheel support section (41', 41'') supports the brake unit (51', 51''). The front wheel portion according to any one of claims 1 to 5.
7. The support arms (23', 23'') are equipped with connecting members (24', 24'') for connecting to the steering system. The front wheel portion according to any one of claims 1 to 6.
8. The shock absorber (26', 26'') comprises a damping element (63', 63'') and an elastic element (61', 61''), particularly a helical spring. The front wheel portion according to any one of claims 1 to 7.
9. The damping elements (63', 63'') and elastic elements (61', 61'') are arranged around a common axis or around two substantially parallel axes. The front wheel portion according to feature 8.
10. The two support arms (23', 23'') are connected together by a steering link (29). The front wheel portion according to any one of claims 1 to 9.
11. The inclined four-bar link (21) is positioned higher than the suspension four-bar link (25', 25''). The front wheel portion according to any one of claims 1 to 10.
12. The front wheel frame (9) has a steering sleeve (11) integrally formed with it, and a steering column (13) is rotatably housed within the steering sleeve (11), and the steering column (13) is restrained by two support arms (23', 23'') by a steering link (29). The front wheel section according to any one of claims 1 to 11.
13. At least one rear drive wheel (7) and Having a front wheel portion (2) as described in any one of claims 1 to 12, The first front steering wheel (3') is supported by the wheel support portion (41') of the first suspension unit (28'), and the second front steering wheel (3'') is supported by the wheel support portion (41'') of the second suspension unit (28''). A vehicle characterized by the following features.
14. The vehicle, Front wheel frame (9) and A pair of front steering wheels (3', 3'') are connected to the front wheel frame (9) by an inclined four-bar linkage (21), Four-bar suspension links (25', 25'') for each front steering wheel (3', 3''), Equipped with, The aforementioned four-bar suspension link (25', 25'') It has four components (23', 23''; 42A', 42A''; 42B', 42B''; 41', 41'') connected around each joint axis (47A', 47A'', 48A', 48A'', 47B', 47B'', 48B', 48B'') and shock absorbers (26', 26''), The shock absorber (26', 26'') is constrained by two components (23', 23''; 41', 41'') of the four-bar suspension link (25', 25'') such that the length of the shock absorber (26', 26'') changes in accordance with the movement of the four-bar suspension link (25', 25''). In vehicle (1), With the four-bar suspension links in any position and each wheel in any position, the articular axes of the four components of each four-bar suspension link (25', 25'') are parallel to each other, and the articular axes (47A', 47A'', 48A', 48A'', 47B', 47B''; 48B', 48B'') between the four components (23', 23''; 42A', 42A''; 42B, 42B''; 41', 41'') of each four-bar suspension link (25', 25'') are perpendicular to the plane containing the rotation axis (43', 43'') of each front wheel (3', 3''). Each suspension four-bar link (25', 25'') is equipped with a support arm (23', 23'') extending toward the inclined four-bar link (21), and the inclined four-bar link is positioned higher than the front steering wheels (3', 3''). The support arms (23', 23'') of each four-bar suspension link (25', 25'') are rotatably connected to each side portion (35', 35'') of the inclined four-bar link (21) so that they rotate around each steering axis (27', 27''). The plane is a plane parallel to the longitudinal direction of the shock absorber. A vehicle characterized by the following features.