Patent GB-190806380-A (GB)
Title: Improvements in Mechanism or Gearing for Transmitting Motion to the Driving Wheels of Motor-driven-vehicles from Motors used to Drive them.
Inventor: EVANS THOMAS FRANCIS
Filed: 1908-03-23
Granted: 1909-04-23
Abstract: 6380. Evans, T. F. March 23. Motor road vehicles.-Comprises friction driving- gear employing two disks connected one to each road wheel, and two rollers driven from the motor, giving a continuously variable speed-ratio and reverse, and providing for starting and stopping, or independent driving of the wheels to facilitate running round curves ; the independent driving of the wheels is effected in accordance with the adjustment of the steering-gear. Fig. 1 shows a sectional elevation on the rear axle of the vehicle, Fig. 2 a central longitudinal section, and Fig. 3 a plan. The disks a, b, mounted on shafts 7 connected one to each road wheel, are made of conical or of increasing or varying conical form to facilitate the engagement or disengagement of the driving-rollers e, f by vertical adjustment of the shaft g on which the rollers are mounted, this shaft g being driven by universal joints from the motor. The shaft g is mounted in vertically adjustable bearings in a frame h carried in a tubular pivot i. The frame h may be turned in the pivot i in an horizontal plane by means of an arm 19 connected to a hand-lever, for the purpose of moving the rollers from one disk to the other for reversing. The bearings l, m of the shaft g are mounted in vertical guides in the frame h, and are pressed downwards, so as to engage the rollers, by springs 34. In order to disengage both rollers, the bearings l, m are raised simultaneously by a member 1 connected to a spindle 2, the lower end of which is engaged by a cam 3 mounted on a shaft 10 connected by an arm 30 to a pedal. The end of the member 1 when in its lowest position engages a sector 23, which is notched or otherwise adapted to hold the frame in any position for either the forward or reverse drive. This arrangement ensures that no adjustment of the frame h to move the rollers from one disk to the other can take place unless the rollers are lifted and thus disengaged. The adjustment of the frame h and rollers in an horizontal plane just referred to is effected simultaneously with the adjustment of the rollers radially for varying the speed-ratio, so that for every radial position of the rollers there is a corresponding angular position of the frame h. This simultaneous adjustment of the rollers is effected by bell-crank levers carried in bearings 29 on the frame h, the arms 27 of the levers engaging cam-surfaces 26, shown also in Fig. 5, fixed to the casing 5 which encloses the gearing. Either of the bearings l, m may be raised independently of the other so as to disengage the corresponding roller by means of the steering-gear when running round curves. Rods o, p connected to the bearings are brought respectively over tappets q, r or s, t according to the adjustment of the frame h, these tappets being pivoted in brackets secured to the casing 5. The tappets s, t are raised alternatively by their respective cams w, u mounted on opposite sides of a spindle y, and the tappets q, r are similarly raised by cams on a spindle z, the two spindles y, z being connected by a rod 14 to an arm 15 mounted on a spindle connected to the steering-gear, so that one or other of the rollers is disconnected according to the direction in which the car turns, and the forward or reverse adjustment of the gear. The disks and the bowls may be roughened, grooved, or otherwise treated so as to increase the adhesion. Other speed-varying mechanism may be employed in conjunction with that described, in order to give a wider range of variation. The frame h may be moved in curved or other guides instead of about a pivot, and the guides for the bearings l, m may be inclined inwards at their lower end. The friction disks may be placed in any inclined, horizontal, vertical, or other convenient position. The friction rollers need not be moved out of engagement with the disks before being moved radially, although this arrangement is preferable. The shafts on which the conical disks are mounted may be in line, or plane disks may be used canted relatively to one another so that their shafts are not in line.