WO2014006573A1

WO2014006573A1 - Tilting vehicle

Info

Publication number: WO2014006573A1
Application number: PCT/IB2013/055435
Authority: WO
Inventors: Antonio SPONZIELLO; Alessia SANTANDREA
Original assignee: Sasp Innovation Srl
Priority date: 2012-07-04
Filing date: 2013-07-02
Publication date: 2014-01-09
Also published as: EP2870060A1; EP2870060B1; ITBA20120044A1

Abstract

Tilting vehicle (200) with at least three wheels (2, 3, 4), two (3, 4) of them being steering and arranged on the same axle, comprising a handlebar (16) constrained to the frame (1), two side head tubes (14, 15) to which there are hinged two side steering tubes (17, 18) to which the steering wheels (3, 4) are constrained; means ( 19, 20, 21, 22, 23, 24, 25, 26, 27) for the transmission of steering motion from the handlebar (16) to said steering wheels (3, 4)wherein a first pinion (7) is solidly constrained to the frame (1), and two further pinions (6, 8), configured to rotate with axes (28, 30) parallel to said first pinion (7), are solidly constrained to said side head tubes (14, 15), the relative position of the axes (28, 29, 30) of said first and two further pinions (6, 7, 8)being defined by a rigid crossbar (5) to which the first and two further pinions (6, 7, 8) are rotatable constrained, and the vehicle further comprises means for the transmission of motion from the first (7) pinion (7) to the two further pinions (6, 7, 8).

Description

TILTING VEHICLE

The present invention relates to a new embodiment of a mechanical assembly for a tilting vehicle having at least three wheels, two of them being steering wheels and being arranged on the same axle. In particular, the mechanical assembly can be used with tilting vehicles having two steering front wheels and one or two driving rear ones. For simplicity, in the following and in the drawings it is referred to a tilting vehicle having two steering front wheels and one driving rear wheel. According to the present invention, with tilting vehicle with two front steering wheels and one rear it is intended a vehicle which during cornering can be tilted inward the curve so that the centrifugal force can be balanced by the weight of vehicle and driver. In practice, it is a motorbike having two front steering wheels instead of only one. The advantage of using two front wheels instead of one consists substantially in a greater stability during straight running and cornering, since the probability of the front wheels to lose the adherence or the contact with the road is lower. At the state of the art, there are known many embodiments of tilting vehicles and in particular of tilting three-wheeled vehicles. Some examples are described in documents EP 1484239, WO 2012/007819, EP 1180476 and EP 2368729.

For example, in EP 1484239 it is described a tilting three-wheeled vehicle with two front steering wheels, comprising a frame, a handlebar, a rear wheel rotating with respect to the frame and a steering front unit, characterized in that there are provided two horizontal crossbars connected by means of hinges to two side head tubes (to which the steering front wheels are constrained) and by means of other hinges to the frame.

It is substantially used a linkage known as "four bar linkage" which has some drawbacks in terms of dimensions. As yet described, it is in fact needed to use two horizontal crossbars for the transmission of the roll motion from the frame to the steering front wheels.

Another embodiment can be found in WO 2010015986, in which it is described a tilting system for a vehicle with three wheels, of which two are coupled on the same axle, characterized in that it comprises a four bar linkage for the connection of each wheel coupled on the same axle to the frame of the vehicle. In almost all the documents known at the state of the art it is provided the usage of a four bar linkage which needs two rigid crossbars to be used, thus resulting in some constraints in the terms of vehicle design, which are linked to dimensions and arrangement of components.

Therefore, aim of the present invention is to provide a mechanical assembly for tilting vehicles which does not use the linkage known as four bar linkage for the transmission of the roll motion from the frame to the steering wheels but which uses a kinematic group which, as it is better described in the following, allows greater design freedom.

According to another aspect, aim of the present invention is to provide a tilting vehicle comprising a mechanical assembly not using the four bar linkage.

These aims are achieved by the present invention, since it is a mechanical assembly for tilting vehicle with at least three wheels, two of which are steering and arranged on the same axle, comprising a handlebar constrained to the frame by mean of a cylindrical hinge, two side head tubes to which the steering tubes of said steering wheels are hinged, means for the transmission of the steering motion from said handlebar to said wheels characterized in that on a rigid crossbar there are hinged a pinion solidly constrained to the frame and two further pinions solidly constrained to the side head tubes, the rotational axes of such pinions being parallel between each other and the relative position of said axes defined by said rigid crossbar, and in that said mechanical assembly further comprises means for the transmission of motion from said first pinion to said pinions constrained to the side head tubes. It is to be specified that the mechanical assembly above described can also be applied to two not steering wheels arranged on the same axle. In this case, there are no means for the transmission of the steering motion from the handlebar to the wheels.

These and other advantages will be clearer from the detailed description of the invention, which refers to the appended figures 1 to 17.

In figures 1 to 3, there are shown two preferred embodiments of the present invention.

Figure 1 shows a vehicle (200) comprising a frame (1) to which it is constrained a rear wheel (2), and by means of a mechanical assembly, better described in the following, two steering front wheels (3, 4) .

Said steering front wheels (3, 4) are constrained by means of independent suspensions to two side steering tubes (17, 18), which in turn are constrained to two side head tubes (14, 15) by means of cylindrical hinges. The axes (31, 32) of such cylindrical hinges represent the steering axes of the two front wheels (3, 4) .

In the appended figures, for simplicity there are not shown the possible independent front suspensions of the vehicle which connect the hubs of the front wheels (3, 4) to the respective side steering tubes (17, 18), since they can be similar to any front suspension of motorbikes. For the same reason, there are not represented the front shock absorbers and the possible rear suspension of the vehicle which connects the hub of the rear wheel to the frame.

The front mechanical assembly comprises a handlebar (16) constrained to the frame (1) by means of a cylindrical hinge. To the handlebar (16) there are connected means (19, 20, 21, 22, 220, 23, 24, 25, 26, 27) for the transmission of steering motion to the front wheels (3, 4). In figure 1 it is shown a transmission of steering motion carried out by means of steering levers (21, 22, 220, 23) constrained to two tie rods/struts (19, 20) by means of spherical hinges (24, 25, 26, 27) . Other linkages known at the state of the art for the transmission of steering motion can be used in association with the mechanical assembly according to the present invention.

The transmission of roll motion from the frame (1) to the side head tubes (14, 15) occurs by means of a linkage comprising a rigid crossbar (5) to which there are hinged three pinions (6, 7, 8) solidly constrained to the frame (1) and to the side head tubes (14, 15) and means for the transmission of rotational motion from the pinion (7) constrained to the frame (1) to the pinions (6, 8) constrained to the side head tubes (14, 15) .

Conveniently, the pinions (6, 7, 8) can be keyed on the shafts (11, 12, 13), which in turn are hinged to the crossbar (5) and solidly constrained to the frame (1) and to the side head tubes (14, 15), as it is shown in figure 1.

The rigid crossbar (5) constrains the relative positions of the pinions (6, 7, 8) while does not constrain the rotation of the same. The means for transmission of rotational _ .. motion between the pinions can comprise idle wheels (9, 10) as it is shown in figures 1 and 2, or a chain or belt (150), as it is shown in figure 3.

Conveniently, in case of using chains or belts as means for transmission of rotational motion between pinions, on the shaft (12) it can be needed that two pinions (7, 70) are to be keyed, instead of one, as it is shown in figures 4, 6, 8, 10 and 13. In this way, a chain or belt (90) transmits the motion from the pinion (7) to the pinion (8), while another chain or belt (100) transmits the motion from the pinion (70) to the pinion (6). Such measure cannot be needed when the axes (28, 29, 30) of the pinions are not coplanar, as it is shown in figure 3.

Other details of a preferred embodiment in case of using chains or belts for the transmission of the rotational motion between the pinions are shown in the following figures 14 to 17, which show three exploded views and an assembled one of the embodiment .

As it is shown, the constrain to the rigid crossbar (5) of the shafts (11, 13), on which the pinions (6, 8) are keyed, can occur by means of bushings (33, 34) which are provided with a hole, whose axis (28, 30) is eccentric with respect to respective axes (36, 37) of the same bushings. The bushings (33, 34), which are provided with an enlargement in the front part which works as a stop, can be introduced in suitable holes provided in the crossbar (5), in which they are free to rotate. The relative rotation of the bushings (33, 34) with respect to the crossbar (5) can be blocked by means of lock nuts (38, 39) with respective locking washers .

Other means for blocking the relative rotation of the bushings (33, 34) with respect to the rigid crossbar (5) can be conveniently used.

As it is shown in figures 14 to 17, the shafts (11, 13) solidly constrained to the side head tubes (14, 15) are housed in the eccentric holes provided in the bushings (33, 34) (introduced in turn in corresponding holes of the crossbar (5)) and the pinions (6, 8) are keyed on the shafts (11, 13) (for example by means of keys) _and_ blocked axially with means known at the state of the art as retaining rings .

Once the system is assembled in this way, it is clear that a rotation of the bushings (33, 34) inside the holes provied in the crossbars (5) will cause a shifting of the axes (28, 30) of the shafts (11, 13) and so of the pinions (6, 8), from the rotational axis (29) of the central pinions (7, 70). Therefore after assembling the system and introducing the transmission belts (or chains) (90, 100), it is possible that the belts (or chains) are suitably tensioned by rotating the bushings (33, 34) and in the following by tightening the lock nuts (38, 39) to block the relative rotation of bushings with respect to the crossbar (5) .

Conveniently, in order to transmit the motion from the central pinion to the side ones, other transmission means and kinematic configurations can be used, as for example, the use of a rack or the use of further pinions and/or gears.

For example, as it is shown in figure 11, the pinions (6, 7, 8) can be bevel gears, and the transmission of motion from the pinion (7) constrained to the frame (1) to the pinions (6, 8) constrained to said side head tubes (14, 15) can occur by means of shafts (199, 201) rotatable constrained to the crossbar (5) and to whose ends the bevel gears (202, 203, 204, 205), meshing with the pinions (6, 7, 8), are keyed.

In this way the aim of constraining the roll motion of the side head tubes (14, 15) to the one of the frame (1) without using a four bar linkage is reached, and by using only one rigid crossbar (5) . Conveniently, it is possible to provide the vehicle with devices able to block the relative rotation of the crossbar (5) with respect to the frame (1) and so the roll motion of the vehicle. Such devices, suitably activated by the user, can be used to facilitate the stop and re-start steps, besides the vehicle parking, since they avoid its fall.

According to a preferred embodiment the axes (28, 30) of the two pinions (6, 8) constrained to the side head tubes (14, 15)_. are in the middle planes of the front wheels (3, 4) and are coplanar with the axis (29) of the pinion (7) constrained to the frame (1) and the transmission ratio between the central pinion (7) and the side ones (6, 8) is equal to 1 (figures 5 and 6) . With this configuration during cornering the middle planes of the front wheels and the one of the rear wheel remain parallel and equidistant between each other ( figures 7 and 8 ) .

For this particular kinematic configuration it is appended a perspective view of the vehicle (figures 1 and 4), a front one during straight running (figure 5 and 6), a front one during cornering (figures 7 and 8), a top view (figures 9 and 10) and a side view (figures 12 and 13) . According to other preferred embodiments, the axes of the two pinions (6, 8) constrained to the side head tubes (14, 15) are not coplanar with the axis of the central pinion (7) and/or the transmission ratio between side pinions and the central one is other than 1 (figures 2 and 3) .

What is described and shown in the appended figures represents the description of preferred embodiments of the invention defined in the following claims.

Claims

1. Tilting vehicle (200) with at least three wheels, two ^' of them being steering (3, 4) and arranged on the same axle, comprising:

- a handlebar (16) constrained to the frame (1) of said tilting vehicle by means of a cylindrical hinge ;

- two side head tubes (14, 15), to which there are hinged two side steering tubes (17, 18) to which said steering wheels (3, 4) are constrained;

- means (19, 20, 21, 22, 220, 23, 24, 25, 26, 27) for the transmission of the steering motion from the handlebar (16) to said steering wheels (3, 4); characterized in that

a pinion (7) is solidly constrained to the frame (1), and two further pinions (6, 8) configured to rotate with axes parallel to said first pinion (7) are solidly constrained to said side head tubes (14, 15), the relative position of the axes (28, 29, 30) of said pinions being defined by a rigid crossbar (5) to which the pinions (6, 7, 8) are rotatable constrained,

and in that

said mechanical assembly further comprises means for the transmission of motion frorr. said first pinion (7) to said pinions (6, 8) constrained to said side head tubes (14, 15).

2. Vehicle according to claim 1, characterized in that said pinions (6, 7, 8) are keyed on shafts (11, 12, 13), which are hinged to said rigid crossbar (5) and solidly constrained to the head tubes (14, 15) and to the frame (1) .

3. Vehicle according to claim 1 or 2, characterized in that said means for the transmission of motion comprise a chain or belt (150) or a rack or idle wheels (9, 10) hinged to said rigid crossbar (5) for the transmission of motion from said pinion (7) constrained to the frame (1) to said pinions. (6, 8) constrained to said side head tubes (14, 15).

4. Vehicle according to claim 1 or 2, characterized in that said pinions (6, 7, 8) are bevel gears and the transmission of motion between the pinion (7) constrained to the frame (1) and the pinions (6, 8) constrained to said side head tubes (14, 15) occurs by means of shafts (199, 201) rotatable constrained to the crossbar (5) and to whose ends the bevel gears (202, 203, 204, 205), meshing with the pinions (6, 7, 8), are keyed.

5. Vehicle according to claim 2 or 3, further comprising a second pinion (70) keyed on the same supporting shaft (12) of said pinion (7) constrained to the frame and characterized in that a first chain or belt (90) transmits the motion from the first pinion (7) constrained to the frame to the pinion (8) constrained to a first side head tube (15) and a second chain or belt (100) transmits the motion from the second pinion (70) constrained to the frame to the pinion (6) constrained to a second side head tube (14).

6. Vehicle according to any one of the preceding claims, characterized in that each of said steering wheels (3, 4) arranged on the same axle is constrained to the respective side steering tubes (17, 18) by means of an independent suspension.

7. Vehicle according to any one of the preceding claims, characterized in that said axle on which said steering wheels (3, 4) are arranged is the front axle of the vehicle.

8. Vehicle according to any one of the preceding claims, characterized in that the axes (28, 29, 30) of said pinions (6, 7, 8) are coplanar.

9. Vehicle according to any one of claim 1 to 7, characterized in that the axes (28, 29, 30) of said pinions (6, 7, 8) are not coplanar.

10. Vehicle according to any one of the preceding claims, characterized in that the motion transmission ratio between said pinion (7) constrained to the frame (1) and said pinions (6, 8) constrained to said side head tubes (14, 15) is equal to 1.

11. Vehicle according to any one of claims 1 to 9, characterized in that the motion transmission ratio between said pinion (7) constrained to the frame (1) and said pinions (6, 8) constrained to said side head tubes (14, 15) is other than 1.

12. Vehicle according to any one of the preceding claims, characterized in that the distance of the axes (28, 30) of said pinions (6, 8) constrained to said side head tubes (14, 15) from the axis (29) of said pinion (7) constrained to the frame is adj ustable .

13. Vehicle according to claim 12, characterized in that said pinions (6, 8) are rotatable constrained to bushings (33, 34), free to rotate about their axes (36, 37) in suitable holes in the crossbar (5) and provided with means (38, 39) to block the relative angular position of said bushings with respect to the crossbar (5), the rotational axes of the pinions (6, 8) being not coincident with the rotational axes (36, 37) of said bushings (33, 34) .

14. Vehicle according to any one of the preceding claims, further comprising means for blocking the rotation of the crossbar (5) with respect to the frame ( 1 ) .