Vehicles having two front rolling and steering wheels and at least a rear driving wheel

• US 20020190494A1
• Filed: 06/20/2002
• Published: 12/19/2002
• Est. Priority Date: 06/02/2000
• Status: Active Grant

• Current Assignee: Piaggio & C SPA (Immsi SPA)
• Original Assignee: Aprilia S.p.A. (Immsi SPA)
• Inventors: Cocco, Gaetano, Rafaelli, Andrea, Scomazzon, Leandro
• Granted Patent: US 6,763,905 B2
• Time in Patent Office: Days
• US Class Current: 280/124.135
• CPC Class Codes: B60G 21/007 means for adjusting the wheel inclination
• CPC Class Codes: B60G 2200/144 with two lateral arms forming a parallelogram
• CPC Class Codes: B60G 2300/122 Trikes
• CPC Class Codes: B62D 9/02 combined with means for inwardly inclining vehicle body on bends
• CPC Class Codes: B62K 2005/001 Suspension details for cycles with three or more main road wheels
• CPC Class Codes: B62K 5/027 Motorcycles with three wheels specially adapted for disabled riders B62K5/023
• CPC Class Codes: B62K 5/05 characterised by a single rear wheel
• CPC Class Codes: B62K 5/10 with means for inwardly inclining the vehicle body on bends

Abstract

Motor-vehicle having at least a rear driving wheel and two front rolling and steering wheels connected to each other by a linkage mechanism (15; 15bis) provided with a suspension system (19) that comprises at least a pair of shock-absorbing struts (60A, 60B; 60C, 60D) and rocking levers (61A, 61B; 61C, 61D) associated therewith. An interconnecting latticework (14) extending along the median plane (PM) of the vehicle supports the axis (A) of the pins (50, 51; 57, 58) of the rocking levers (61A, 61B; 61C, 61D) so that it is caused to lie on the same median plane and parallel to the axes (X, Y) of the fulcrum pins (52, 53, 54) of the cross bars (20, 21, 22, 23) of the linkage mechanism (15). The rolling speed of the front wheels can be varied.

Claims

1. Vehicle having a rigid chassis (1, 2), at least a rear driving wheel (4) and two front steering wheels (17) connected to each other by a linkage mechanism (15;

15bis) that comprises a first pair (20, 21) and a second pair (22, 23) of rigid overlying cross bars which have their fulcra centrally on pins (52, 53, 54) having their axes (X, Y) parallel to each other and lying on the median plane (PM) and which are connected to rigid wheel-supporting means (24, 25;

28, 29) by means of ball-and-socket joint members (30, 31, 32, 33) with their axes (J, K, L, M) parallel to the median plane (PM), said linkage mechanism being further provided with a suspension system (19;

19bis) that comprises at least a pair of shock-absorbing struts (60A, 60B;

60C, 60D) whose upper end portions (62A, 62B;

62C, 62D) are on the opposite end portions of rocking levers (61A, 61B;

61C, 61D) having their fulcrum on an interconnecting structure (14) between the linkage mechanism and the chassis, and whose lower end portions (63A, 63B;

63C, 63D) are connected to one of said pairs of cross bars, characterized in that said interconnecting structure is a lattice-work (14) extending on the median plane (PM) so that the axis (A) of the pins (50, 51;

57, 58) of the rocking levers (61A, 61B;

61C, 61D) is caused to lie on the same median plane and parallel to the axes (X, Y) of the fulcrum pins (52, 53, 54) of the cross bars (20, 21, 22, 23) of the linkage mechanism (15;

15bis), in such a manner that, in the various trim of the vehicle, the distances between the axes (RA, SA, RB, SB;

RC, SC, RD, SD) of the opposite end portions of the shock-absorbing struts (60A, 60B;

60C, 60D) are variable regardless of the fixed distance (C) between the axes (X, Y) of the fulcrum pins (52, 53, 54) of the cross bars (20, 21, 22, 23).

2. Vehicle according to claim 1, characterized in that the rocking levers (61A, 61B;

61C, 61D) are adapted to rotate about their own fulcrum axis (A) so that, for a given rolling angle (φ

) of the front wheels, the cross bars (20, 21, 22, 23) of the linkage mechanism (15;

15bis) undergo an inclination (β

) which is greater than the rolling angle and is correlated with the angle of rotation (γ

) of the rocking levers (61A, 61B;

61C, 61D).

3. Vehicle according to claim 1 or 2, characterized in that the ball-and-socket joint members (30, 31, 32, 33) that are a part of the linkage mechanism (15) have their centres aligned along the steering axes (Z1, Z2) of the front wheels, and that the axes (J, K, L, M) of the same ball-and-socket joint members (30, 31, 32, 33) lie on the equatorial planes of the corresponding wheels that are parallel to said median plane (PM).

4. Vehicle according to claim 3, characterized in that said steering axes (Z1, Z2) are inclined with respect to the vertical so as to confer a forward stroke to the front wheels.