WO1984003074A2 - Vehicle for terrestrial use, particularly a tricycle - Google Patents

Description

Vehicle for terrestrial use, particularly a tricycle.

The invention relates to a vehicle for terrestrial use in particular to a tricycle having an improved arrangement for turning the vehicle from a straight forward direction into a curve and vice versa. Such a vehicle for terrestrial use is already known, equipped with three distantly arranged supporting means for forward movement, two of these supporting means being displaceable in unison by means of a common steering device, said two supporting means being each pivotally arranged on an extended supporting arm at the front part of the vehicle, the third supporting means being of a traditional nature of support only, each relevant extended pivot axis lying in a common plane which intersects the plane containing the said vehicle's supporting contact surfaces and the points of support, each extended pivot axis taking a rear- ward angle of inclination with respect to the vertical plane through the longitudinal axis of the vehicle, the points of intersection of each pivot axis with the horizontal plane of support lying in an outward direction perpendicular to the vehicle's longitudinal axis and sidewardly away, in the case of a tricycle, from the road contacting points with the front wheels. It is an object of the invention to provide for a vehicle of the kind as mentioned before, which, while going into a curve and/or leaving a curved path, provides for a special sensation for its driver that in such a curve, the point of gravity of the vehicle is automatically lowered and displaced to the inner side of the curve, thereby making the driver's comfort optimal and simultaneously overcoming the unpleasant centrifigal forces which normally tend to through a driver in a direction adverse to the direction of turning the vehicle. This problem of being subjected to centrifugal forces, not being cσmpensated in any way, neither by the position of the vehicle itself, nor by a changing position of the driver's seat, is solved by a vehicle which, aceording to the invention provides for a speeifie arrangement as referred to above in that, in addition said points of intersection also are situated outwardly away of each of said points of contact, the arrangement being suchlike that while the vehicle is traversing a curved path, the vehicle's frame is subjected to a "pendulum" action in the direction of turning, causing a relative different movement while progressively turning, the vehicle's supporting means located at the inner part of the curve are moving more in a forward direction, whereas the supporting means located at the outer part of the curve being more retracted with respect to the said forward movement and vice versa. It has been found that the advantages of the inventive arrangement may be more speetacular if in a vehicle aceording to the invention, each extended pivot axis intersects the opposite pivot axis under a sharp angle at a point above the vehicle, the vertical line of projection from that point, intersecting with the said plane containing the vehicle's supporting contact surfaces and the point of support is located within the vertically projected area of circumference of the vehicle. It appears possible to experience a range of intersecting angles which allow the vehicle to satisfy to the "pendulum" action and it is believed that the angle of intersection for a pivot axis could so ränge from 5° - 50º depending on other construction features of the vehicle which may also determine the extent of the "pendulum" action. Anyhow, the vehicle's body is more or less "offset" during the turning, being given an inclination which results from the relative forward and backward movement of the supporting means at the front of the vehicle which is unique. A vehicle may thus be provided with two extended support arms mounted upon steering pins fixedly arranged with respect to the vehicle's frame, the arrangement being such that movement in unison of each supporting arm in view to its pivot and the arrangement of each pivot being defined by an angled position in a rearward direction and simultaoeously having said extended two pivot axis diverging in a downward direction, causing the "pendulum" action whereby the points of intersection of each pivot axis with the supporting plane σf the vehicle are situated in an outward direction with respect to the supporting means and away from the vehicle's longitudinal axis

Ailthough a vehicle aceording to an improved embodϊment cσuld be achieved in its simplest construction as described before, yet additional means could be provided, thereby enabling the advantages of the "pedulum" action by the provision of at least one adjustable control means for the relevant position of the pivot pin with respect to its housing, said adjustable means being integral with the pivot housing, said means consisting of helically disposed guiding element on the pivot pin and cooperating elements on the housing causing the relative positioning of the pivot pin with respect to its housing to be lifted and/or lowered respectively while the pivot housing is rotated during the steering operation. A Variation of this provision can be appreciated while providing said helical guiding elements with differentiated cooperating portions per each pivot for increased effectiveness of the "pendulum" action, by providing two reversely directed helical surfaces are provided on the pivot pin and inside the pivot housing, separated by a neutral zone enabling the accelerated Operation of desired "pendulum". Moreover it may be clear that as described in the foregoing, mechnically operated means can promote the aforesaid invented operation, also Special control means could be provided for automatically adjusting the "pendulum" action by means of a signal, derived from the instantaneous position of the steering means. For someone skilled in the art it will be possible to understand the ways and means for carrying out the invention after having disclosed herein the various aspects of introducing the "pendulum" effect to the vehicle's Operation.

In view to the above it will become apparent that various mechanic al or other devices may be combined with the constructional aspects in the application of the invention in order to improve the advantages. Moreover it will also be understood that the aforementioned signal could be easily derived from an accelerating and decellerating signalling device in combination with the signal initiated from the steering device. Especially when mαtorized tricycles are used, the specific speed charaeteristics of the vehicle become more important to be considered while providing for the desirable inclination of the pivot axis in relation to the pendulum action.

It is also remarked hereby that the pendulum action could easily be realized for e.g. roller skates in which the length of supporting arms are not comparable with those for a tricycle, however the principle of the invention could still be applied.

Allthough in the description some indication is given about the position and a preferred angle of the relevant pivot axis it must be clear that further experiments are still possible, thereby perhaps giving still better results provided that the pendulum action by inclined arrangement in relation to the length of a supporting arm is fully understood.

Other objects of the invention will appear in the following description and appended Claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference numerals designate corresponding parts in the several views. Several applications of the invention are illustrated by way of example in the drawings wherein:

Fig. 1 is a side elevation of a tricycle showing the present invention; Fig. 2 is a plan view showing the arrangement of the dirigible front steering construction of the tricycle shown in Fig. 1 having the steering mechanism located in front of the driver and this tricycle may carry two persons, the person sitting on the back seat resting with his legs at both sides of the driver;

Fig. 3 is a side elevation and Fig. 4 is a plan view of another tricycle for a single person wherein the steering mechanism aceording to the invention is located and operated respectively from under the driver's seat; Figs. 5 up to and inclusive Fig. 10 are schematic views showing various positions of the wheels of a tricycle aceording to the invention and Fig. 11 and Fig. 12 are a front and side view respectively of the connecting tubes for operating the steering construction.

Before explaining the invention in detail it is to be understood that the detailed description is Iimited to the essential operating parts only, vehicle constructional parts not forming a part of the invention are not specifically described under the assumption that experts may easily understand a vehicle's construction. The car body 1 is in a known way connected to the main supporting frame 2 of the tricycle and this frame is supported on two front wheels 3 and one rear wheel 4. The steering mechanism consists of a pair of wheel supporting arms 5 which are rotatable around a steering pin 6 which is fϊxed with respect to the main frame 2. The supporting arm 5 for the wheel 3 is with its housing 7 rotatably fixed around the steering pin 6 and the housing is further provided with a protruding bracket 8 which has a pivot 9. A lever 10 is with its one end pivotally coupled with said pivot 9 and with its other end with one leg 11 of a V-shaped steering bracket 12 which is rotatably fixed upon the frame 2. The axis of rotation 13 of the V-shaped bracket can be operated directly by the driver e.g. through a transmission mechanis m by means of a steering means 14 such construction being known per se so that it need not further be explained herein. Moreover, it will be clear that any other device, e.g. a shock absorbing device 15 may be ϊncorporated in the wheel supporting arm 5 too. The invention resides now in the particular location and position or the st eering pin 6 which forms the axis of rotation for the supporting arm 5 of the front wheel 3. This position is defined in such a way, that the pivot axis 16 is placed under an angle of about 30 ° with respect to a vertical plane and thereby also iπcliπed in an outward and forward direction. The angled position of this rotational axis 16 with respect to the horizontal plane 17 is such, that the intersecting line 18 of both planes is situated just at the contacting line of the front wheels 2 or in a direction in front of these wheels.

The extended sides 16 (pivot axis) αf the triangle of which the line 18 is a basis line intersect the horizontal plane 17 at the points 19 and both points are cleariy located at the outside of the wheels 2 as shown in Fig. 2.

/on or about In Figs. 3 and 4 another embodiment of a tricycle is shown for the use of one person only. In this case, the steering means 20 are located under the seat of the driver. Here again a V-shaped bracket 21 is rotatably connected at 22 with the frame 2 of the vehicle and the ends of the legs 23 are pivotally coupled at 24 to levers 25 which are at their ends at 26 pivotally connected to the bracket 27 of the housing 28 which is connected to the wheel supporting arm 29 in a similar way as described above. Both levers 25 are crossing each other here, contrary to the position of the levers 10 of Figs. 1-2 lying in the same plane.

The operation of the vehicle and its behaviour on the road both are entirely known as lang as it moves in a straight line forward or backward, the wheels thereby follαwing the arrowed lines in Figs. 1-4. However as soαn as the driver turns the steering means, a pattern, different from what is understood as "normally turning" will be experienced. The operation, as a result of the particular position and inclination of the steering pins results into a kind of rocking movement of the vehicle, that is to say, while turning of the front wheels is effected, one longitudinal side of the frame of the vehicle is üfted whereas the opposite side is than lowered, the lowering side being the side of the vehicle in the direction of turning. By the choice of the triangle, described before and its position, which in fact defines the operation of the behaviour of the vehicle while making turns, it will be clear that the aimed advantage is obtained. The vehicle is allowed to behave in such a way that a natural position is induced; the driver autαmatically takes the desired incliπed position which is the position in which the vehicle frame and body are moving while turning. This novel experience is called a momentary "pendulum" enabling the driver at the same time to maintain his "natural" comfortable position while making a turn. This "pendulum" action can only satisfactorily be obtained if the precise invented position of the steering pins with respect to the frame of the vehicle are taken into account.

Figs. 5-12, showing schematically certain various positions of a tricycle's basic frame only, will be explained hereafter.

Figs. 5 and 6 are a front view and a side view respectively of a tricycle base which has the characteristic declined position of the steering pins and showing a road surface representing the "pendulum" action and position respectively. Figs. 7 and 8 show similar views as in the previous Figs. 5 and 6 but the inclination of the road surface is steeper. The front wheels 30 and 31 are rotatably mounted upon the wheel supporting arms 32 and 33, which are fixed in a way described before, the position/location of the pivot axis

34 and 35 respectively being each in a verticai plane and the angle of intersection with the horizontal plane 36 is shown in Fig. 6. The point of intersection of the pivot axis 34, 35 is indicated at 37. Contrary to the equϊdistant position of both pivot axis 34 and 35 in Fig. 5, the pivot axis 38 and 39 do intersect in plane 40 which contains both axis and which plane, in an inclined position intersects the horizontal plane 41 at the points 42 and 43 respectively. Compared with the position of the intersecting pivot axis 16 in Fig. 2, 28 in Fig. 4 and 38, 39 in Figs. 7-8, the equidistant axis 34 and

35 of Figs. 5 and 6 take an extreme position as they intersect in the infinite and yet intersect the road surface at points which are positioned both at the outside of the wheels.

Figs. 5-10 indicate the position of the wheels after they were turned 9 0°, a dotted line showing the wheels 44 in a theoretical position in which the road surface is shown under an angle indicated by the numeral 45. Figs. 5-6 moreover indicate the difference in height position between the opposed wheels 44 shown with the numeral 46 and it follows from the drawing that the smaller the angle 46 is chosen, the greater the angle of inclination of the wheels 44 with respect to the road surface will be while progressively making a turn. Because of the relative position of the wheels on the road surface while steering through a curve, it will be clear that the mutual displacement of the plane of movement of the wheel changes from two equidistant surfaces which are perpendicular to the road surface, when the vehicle is moving straight forward, changes into two equidistant surfaces which no longer are perpendicular to the road surface, but instead both (wheel) surfaces tend to take progressively an inclined position with respect to the road surface, thereby causing the natural comfortable "pendulum" position of the driver in his vehicle. This again is shown in Figs. 7-8 wherein the preferred position of the pivot axis 38 and 39 results in a much great er angle of inclination 47 in the theoretical angle of rotation of the wheels 48. It means also that the more the points of intersection 42 and 43 beeome located away from the contact points between the wheels and the road surface, the more the angle of rearward inclination decreases, that is to say, the more effective the "pendulum" action is experienced.

Naturaily it remains πecessary that the wheels still perform their basic function to roll over the road surface and that the "pendulum" action in the 90º position in Fig. 8 indicates a difference in height at 49 but it will be clear that too heavy forces should preferably not be transmitted to the steering mechanism in case no auxiliary motor means are made available to the driver for automatically overcoming the influence of such relatively heavy steering forces.

Figs. 9-10 show another embodiment of a tricycle frame and the relative position of the wheels 50 and their related pivot axis 51, 52 respectively. The planes of the wheels are slightly inclined with respect to the road surface, indicated by the angles 53 tending to decrease the possible differences between the angles of inclination of the wheels while steering the vehicle through a sharp curve. In Fig. 10 a difference in height between the points of contact of the wheels with the road surface is indicated at 54 and this is caused by the Special configuratiαn αf the wheel supporting arm 55. This arm 55, not being situated in the plane which also contains the pivotal axis 51, 52 can turn around these pivotal axis 51 and 52 respectively, see Fig. 9. This Fig. and Fig. 10 also indicate the two possible positions of the steering parts 56 and 57 respectively which are operable e.g. aceording to the coneept already shown in Figs. 1-2 and Figs. 3-4 respectively. It may well be preferred to perform a tricycle aceording to the invention and have it driven by personal pedal power only although auxiliary pσwer means (battery operated or fuel operated motor means) could easily be integrated. In Figs. 11-1 a detailed solution is schematically shown for use of the vehicle as a tricycle, simply by connecting the wheel supporting arm 58 near the pivot axis 59 with a fixed extended bracket 60 and the parallelly disposed bracket 60 at the opposite side of the vehicle can than be coupled by means of the bar 61. This bar could be used by the driver for direct steering or if desired, the bar 61 can be used for indirect steering, depending on the construction of the vehicle.

In view to the typical position of the wheels of the vehicle while steering through a curve, it will be highly desirable that provisions are made to keep the vehicle in an upright fixed position at a standstill thereby avoiding an instantaneous and unexpected "pendulum" action. Such a provision could than be obtained by locking the steering mechanism but it is also possible to balance the vehicle by means of normal brakes. As a result of the specific inclined position of the wheels when going into a curve, the steering operation may be influenced by the "pendulum" forces which require corresponding counter forces for compensation. These and other inherent measures to be considered are however of a controllable nature and if causing problems, can easily be taken. Insσfar as the invention could also be adopted for all kinds of vehicles to be operated and steered in which the body of the vehicle automatically adopt a preferred inclination while going through curves, an automated control system for compensating forces while doing so, could be integrated to improve its easo Operation.

The invention can be basieally applied to all vehicies which are moving upon a fixed road surface and which are normally subjected to such forces which intend to disturb the behaviour of the vehicle while moving through curves. In this decription reference is made to "wheels" as the means to use the embodiment of the invention but it should be understood that the "wheels" can be replaced by a couple of "floating elements" located under the hull of a ships body as well. As a matter of fact the invented steering aspect definitely causes a controllable displacement of the point of gravity of the vehicle by lowering it as soon as the vehicle is entering a curve, while reversing the action once the curve has been taken. It will be clear from the foregoing that the rear support of the vehicle preferably consists of one wheel or one floating means (boat). However double wheels or equivalent supporting element could be used without deviating from the general concept, provided that the stability of the vehicle is considered to be obtained by three contact points or contact surfaces.

The relative displacement of the supporting eiements under the vehicle while moving through a curve is of such a particular nature that as a result of the invented position and configuration of the supporting arms and an purpose, the regulär pattern of a couple of such supporting elements, while moving through a curve is disturbed for improved comfortability of the users of the vehicle thereby giving them the Sensation of balanced stability in a curve despite the increase of centrifugal forces which now tend to beeome compensated by centripetal forces.

Claims

1. Vehicle for terrestrial use, equipped with three dϊstantly arranged supporting means for forward movement, two of these supporting means being displaceable in unison by means of a common steering device, said two supporting means being each pivotally arranged on an extended supporting arm at the front part of the vehicle, the third supporting means being of a traditional nature of support only, each relevant extended pivot axis lying in a common plane which intersects the plane containing the said vehicle's supporting contact surfaces and the points of support, each extended pivot axis taking a rearward angle of inclination with respect to the vertical plane through the longitudinal axis of the vehicle, the points of intersection of each pivot axis with the horizontal plane of support lying in an outward direction perpendicular to the vehicle's longitudinal axis and sidewardly and outwardly away of each of said points of contact, the arrangement being suchlike that while the vehicle traversing a curved path, the vehicle's frame is subjected to a "pendulum" action in the direction of turning, causing a relative different movement while progressively turning, the vehicle's supporting means located at the inner part of the curve moving more in a forward direction, whereas the supporting means located at the outer part of the curve being more retracted with respect to the said forward movement and vice versa.

2. Vehicle aceording to claim 1, characterized, in that each extended pivot axis intersects the opposite pivot axis under a sharp angle at a point above the vehicle, the vertical line of projection from that point, intersecting with the said plane containing the vehicle's supporting contact surfaces and the point of support is located within the vertically projected area of circumference of the vehicle.

3. Vehicle aceording to claim 2, characterized, by the provision of two extended support arms mounted upon steering pins fixedly arranged with respect to the vehicle's frame, the arrangement being such that movement in unison of each supporting arm in view to its pivot and the arrangement of each pivot being defined by an angled position in a rearward direction and simultaneously having said extended two pivot axis diverging in a downward dϊrection, causing the "pendulum" action whereby the points of intersection of each pivot axis with the supporting plane of the vehicle are situated in an outward direction with respect to the supporting means and away from the vehicle's longitudinal axis.

4. Vehicle aceording to claim 3, characterized, in that the "pedulum" action is obtained by the provision of at least one adjustable control means for the relevant position of the pivot pin with respect to its housing, said adjustable means being integral with the pivot housing, said means consisting of helically disposed guiding element on the pivot pin and cooperating elements on the housing causing the relative positioning of the pivot pin with respect to its housing to be lifted and/or lowered respectively while the pivot housing is rotated during the steering operation.

5. Vehicle aceording to claim 4, characterized, in that said heiieal guiding elements are provided with differentiated cooperating portions per each pivot for increased effectiveness of the "pendulum" action in that two reversely directed helical surfaces are provided on the pivot pin and inside the pivot housing, separated by a neutral zone enabling the accelerated operation αf desired "penduium".

6. Vehicle aceording to one of the foregoing Claims, characterized in that control means are provided for automatically adjusting the "pendulum" action by means of a signal, derived from the instantaneous position of the steering means.

7. Vehicle aceording to claim 6, characterized, in that said control means reeeive said signal in relation to the extent of acceleration and/or decelleration to which the vehicle is subjected.