Improvements in Steering Apparatus for Motor Road Vehicles.
Year: 1899

page_text: Date of Application, 23rd Jan., 1899-Accepted, 25th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in Steering Apparatus for Motor Road Vehicles.
I, EUGÈNE BRILLIÉ, of 17, Rue Philippe de Girard, Paris, in the Republic of
France, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement; —
The object of this invention is to provide improved steering apparatus for motor
road vehicles as hereinafter described.
I will describe the invention with reference to the accompanying drawings in
which
Figure 1 is a vertical section of the mechanism and Figure 2 is a diagram-
matic plan illustrative of the epicycloidal operation thereof.
Figure 3 is a vertical section of a modification of the mechanism.
11 is the steering shaft the axial line of which is indicated at A. To the upper
end of the said shaft is secured the operating device, which may be a hand-
wheel 19, handle-bar, or the like. The said shaft, or rod, 11, is guided by bearings
in a stationary tube 12 on which is secured a toothed pinion 13. To the lower
part of the shaft 11 there is attached a lever 14, through a bearing at one end of
which passes a shaft 15, parallel to the said shaft 11, the axial line of the said
shaft 15 being marked D.
To the upper end of the shaft 15 is secured a toothed segment 16, which is in
gear with the pinion 13; while on the lower part of the said shaft 15 is secured
a crank-arm 17, which controls the steering link (not shewn) which is mounted
on the pivot 18 (the axial line of which is marked C) and extends at right angles
to the plane of Figure 1.
A spring 20 tends to bring the three shafts 11, 15 and 18, into the same vertical
plane.
The operation is as follows:-
As the hand wheel or the like 19 is turned, the axis D of the shaft 15 through
the shaft 11 and lever 14 describes a circle about the axis A of the shaft 11; and
as the segment 16 gears at B with the fixed pinion 13, the pivot 18 of the crank 17,
will through its connection with the said segment describe an epicycloid.
Referring now to the diagram Figure 2: let the axis CC of the crank pin 18
pass through the primitive circle of the toothed segment 16, and occupy the
position B for rectilinear motion. The trajectory of the said pin 18 will then
be an ordinary epicycloid Co C, C₂ ., cutting the line A-D, at B。.
The steering link 21 being at right angles to A-D; or at Boat right angles
to the trajectory of the pin 18; it follows that any abnormal strain applied to the
steering wheels will be transmitted to the pin 18 by the said link 21 in a direction
perpendicular to the trajectory of the pin 18, and can therefore, in no case, impart
any motion to such pin.
Thus, geometrically, the direction is irreversible, whenever the parts are set
for rectilinear forward motion.
By moving the hand-wheel or the like 19, and also, therefore, the axial line D,

page_text: at equidistant angles, D, D, D, and so on, the corresponding positions of the crank-
pin will be B, C₁, C₂, and so on, and the movements of the link 21,-disregarding
its possible obliquity, will be as indicated on a scale E (Figure 2) by the
ordinates 0, 1, 2, 3 and so on.
It will thus be seen that when the hand-wheel or the like 19 is first set in motion,
these ordinates are very close to each other, and will subsequently go on augment-
ing. The steering effect is therefore progressive, or gradual.
It may be desirable, in order to modify the law of progression, to determine the
position of the axis C between D and B. Let it be at Co (Figure 2), for example;
the epicycloidal curve is consequently modified. Nevertheless, if the point Cobe
not too far distant from the point Bo, the steering will continue for all practical
purposes irreversible owing to the action of the spring 20 and of the short lever
arm resisting the forces that might tend to alter the direction.
3
Such is the case graphically represented at the upper part of Figure 2,
where D, D, D, and so on designate the successive positions of the axis D, while
C₁₁, C, C and so on mark the corresponding positions of the pin or pivot C of
the link 21, the movements whereof are indicated on the scale F, with regard
to the ordinates 1, 2, 3 and so on.
1'
3
The same end may be gained, as illustrated in Figure 3, wherein the figures
of reference correspond to those used in Figure 1, the segment 16 being replaced
by the pinion 16 and the pinion 13 by the internal gear 13. The details and
accessories may be varied without departing from the nature of the invention.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim is:-
1. For steering motor road vehicles mechanism whereby the point of attachment
of the steering link is caused to describe an epicycloidal curve, whether on an
outside or an inside circle, substantially as hereinbefore described and illustrated
in the accompanying drawings.
2. In an arrangement according to the preceding claim, the construction, con-
sisting of a steering shaft, carrying at its lower part a lever which terminates in
a sleeve or socket, wherein revolves an auxiliary shaft parallel to the steering
shaft; such auxiliary shaft carrying at one end a toothed segment or a wheel
in gear with a pinion or internally toothed gear secured on the fixed guiding tube
of the steering shate; and, at the other end, the arm of a crank with a pin whereon
the steering link is pivotted; so that by operating the steering shaft, the said pin
is made to describe an epicycloidal curve substantially as hereinbefore described
and illustrated either by the example shewn in Figure 1 or that shewn in Figure 3
of the accompanying drawings.
Dated this 21st day of January 1899
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.