Improvements in or connected with Self Propelled or other Motor Road Vehicles.
Year: 1898

page_text: Date of Application, 7th Mar., 1898-Accepted, 30th Apr., 1898
COMPLETE SPECIFICATION.
Improvements in or connected with Self Propelled or other Motor
Road Vehicles.
I, JAMES YATE JOHNSON, of 47, Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been commu-
nicated to me from abroad by Andrew L. Riker, of the City and County of New York,
in the United States of America, Electrical Engineer), and in what manner the same
is to be performed to be particularly described and ascertained in and by the following
statement :-
This invention relates to the construction of motor or "self-propelled " vehicles,
and more particularly to the running gear thereof, comprising the frame, axles,
driving-mechanism, brake, and steering gear.
The improved running gear herein described, while contrived with special reference
to the employment of an electric motor for propulsion, is applicable to other suitable
motors, the motor itself forming no part of the present invention.
Study of the conditions attending the use of self-propelled vehicles and practical
experience therewith have shewn that they differ materially from those attending
the use of vehicles drawn by an external power, and that, to meet successfully the
conditions arising in practical use, many departures in construction from the best
types of ordinary vehicles are necessary or desirable.
The object of the present invention is in general to meet practically these new
conditions, and to provide a system of construction for self-propelled vehicles
characterized by simplicity, strength, durability, flexibility and facility for manipu-
lation.
The objects of this invention, and the means whereby they can be attained I
will explain with reference to the accompanying drawings, in which :-
Figure 1 is a plan, partly in section, of the running gear of a self-propelled
vehicle;
Figure 2 is a vertical section longitudinally of the hub of one of the front
wheels;
Figure 3 is a longitudinal section of the rear axle, or driving shaft, shewing the
compensation-gearing in the hub of one of the wheels;
Figure 4 is a similar view of one of the ball-bearings of the rear shaft;
Figure 5 shews a modification of the construction illustrated in Figure 2; and
Figure 6 is a detail of the brake.
The principal parts of the frame are the forward axle A, the rear axle B, and the
tubular side bars C, C¹ (Figure 1) forming approximately a rectangular figure. The
side-bars are placed farther apart than in ordinary vehicles. The motor D, (of any
suitable type), is supported by one of the sleeves D¹ enclosing the rear axle; by
the housing D² of the driving gear, and by a cross-har D³. The motor may be
supported at its forward end from the vehicle-body as follows: A depending rod is
pivoted to a lug on the bottom of the vehicle-body. This rod passes through an eye
on a horizontal plate, or nose, extending forward from the motor-casing. Above the
nose is a nut adjustable on the rod, and on the lower end of the rod is a second
adjustable nut. Coil-springs surround the rod, one above and the other below the

page_text: nose of the motor casing, and have their ends pressing, respectively against the nose
and washers held by the nuts. The object of this construction is to take up the
vibratory motion to which motors are subject on first starting. The connections of
the side-bars with the axles are such as to meet the requirements of rigidity, strength,
and flexibility in the desired directions.
In the ordinary type of running gear the front axle is arranged to turn freely upon
a king-bolt, while the vehicle body is supported upon a frame consisting of the rear
axle, a bolster carried upon the front axle by the king-bolt, or fifth-wheel, and con-
nections that hold the bolster parallel with the rear axle, the frame being approxi-
mately rectangular. In the present construction, since the body is supported (by
means of springs, not shewn) directly upon the front axle, without the interposition of
the bolster, the front ax'e must be retained in substantially the same vertical plane
with respect to the body, otherwise, if this axle were free to turn, there would be a
lateral strain, or twisting, of the connections between the two parts.
It is also necessary in this part of the mechanism to make provision for one axle
assuming a different angular position from the other, as, when one wheel is lifted by
an obstacle, or irregularity, in the surface of the road while the other wheels remain
at a lower level, or when one wheel sinks into a rut. In case of a rigid frame this
would produce a dangerous strain on the joints, and also a twist, or torsion, on the
side-bars and axles. The strain, moreover, is proportional to the distance apart of the
side bars, which it is advantageous to motor vehicles to make as great as possible.
These conditions are met, according to the present invention, by making the connection
between one of the cross-bars and an axle rigid, while the other connections are loose.
In the preferred form one side bar (say C) is rigidly connected at its forward end
with the front axle, the connection being made as shewn by hollow union-pieces c c¹
surrounding the axle and brazed, or otherwise secured, thereto. The union-pieces c² c³
of the other side bar C are not rigidly attached to the axle A, bitt loosely surround it,
and are held from longitudinal movement by collars made fast upon the axle in any
way. Thus, when one of the wheels is elevated, the tendency of the axle to twist and
shift its position relatively to the side-bar produces no strain.
The side bars are tied together towards the rear by the cross-bar, or brace, D³.
already referred to. The ends of this brace are not fastened rigidly to the side-bars,
but are connected thereto by means of union-pieces of peculiar form, so as to allow of
sufficient play of the parts. These union-pieces are constructed and arranged as
follows: Each union-piece has a sleeve which surrounds one of the side-bars loosely
and is free to turn thereon, but is held from longitudinal movement by collars made
fast on the bar. Formed integral with this sleeve and below it is another similar
sleeve having its axis at right angles to that of the first. These lower sleeves on the
two union-pieces surround the ends of the cross-brace D³ loosely, but are held from
longitudinal movement thereon by a head, or enlargement, of some sort at each end
of the brace, one pressing against each lower sleeve.
The connection of the rear ends of the side-bars is also devised with reference
to the aforesaid conditions of use, and to give the required rigidity of connection
between the front and rear axles, while providing at the same time for the requisite
flexibility. The sleeves D¹ enclosing the rear axle (or driving shaft) have, each near
their outer ends, an enlargement, or casing, E containing the ball-bearings (see also
Figure 4). This casing has surrounding it a bearing ring, or band e, the surface of
which is of spherical convexity constituting a spherical seating. The side-bars CC¹
each terminates in a collar ex whose inner surface has a concavity corresponding to
the bearing ring e constituting therewith a universal joint. Thus the side-bars can
move both horizontally and vertically, to the necessary extent and with perfect
freedom, relatively to the rear-axle, while the joint possesses the requisite strength.
The elasticity of the side-bar C, sufficient to permit the necessary "give," or play,
of the parts. The vehicle body is held above the front axle by springs attached to
eyes a (see Figures 2 and 5). It is not, of course, necessary though it is advantageous,
that the connection of the side bars to the axle should surround the bearings of the
latter.

page_text: I will now describe the construction of the ball-bearings with reference to
Figures 1 and 4. Since the two at either end are identical in construction, a
description of one will suffice. The casing, or journal box, E, as already stated,
is fastened to the sleeve D¹, within which the driving shaft B, rotates. The outer
side of the said casing is closed by a disc or ring e¹, screwed into the casing,
and having in its inner edge a circular felt, or other washer, e2, which is in contact
with the surface of the shaft B, and makes a tight joint excluding dirt and moisture.
Within the casing, and fast on shaft B, is a collar F, which has, on one side, a
hardened steel face f, which constitutes a bearing surface for the adjacent series of
balls f¹. The entire ball-race is formed by this collar, a hardened ring F¹ surrounding
the shaft, and turning with it, and a series of transverse washers f2, of hardened
steel, separating the adjacent series of balls, (of which there may be any desired
number). These parts form the moveable bearing surfaces. The stationary surface
is formed by the ring F2, attached to the inner wall of the casing. The construction
is such that the entire bearing can be readily removed and replaced.
The thrust of the, shaft is taken between the collar F, on one side and the
ring e¹ on the other. The parts are very easily assembled and adjusted to proper
working positions, and it is only necessary, in order to take up wear, and looseness,
to screw up the rings e¹, which tends to put a tensile strain on the sleeve D¹
and a compression strain upon the shaft B. Thus each ring e¹, and its corresponding
collar F, press firmly upon the intervening balls. This construction obviates the
necessity of adjustment of the ball-bearings which is a very difficult operation for
unskilled persons.
It is well understood that when the vehicle makes a turn, or deviates from a right
line, the opposite wheels on the same axle rotate with differential speed, and in
extreme cases may even rotate in opposite directions. For this reason it is necessary
that each of the two wheels of a pair should be capable of absolutely independent
rotation. In the case of the driving wheels, which must both be positively connected
with, and driven by, the driving shaft, the provision for independent revolution of
each wheel has presented one of the most difficult mechanical problems in the
construction of motor-vehicles. The ordinary arrangement for this purpose consists
in dividing the driving shaft in the middle, or rather in providing two shafts, one
for each wheel, the shafts being connected at their adjacent ends by a compensating
driving connection, usually a bevel gear on the end of each shaft, and two pinions,
engaging therewith, carried by a driving wheel rotating on the axis of the shaft as a
centre. In straightforward motion the pinions acted simply as driving keys for the
bevel gears; but in case of a turn the pinions turned on their own axes as far as
necessary to compensate for the differential speeds of the two wheels. "The main
objections to this system are weakness, due to dividing the driving shaft at, or near,
the middle thereof, complexity of construction, and inaccessibility for repairs.
The compensating driving gear which constitutes a part of the present invention
is illustrated in Figures 1 and 3. The shaft B, already referred to, extends the full
distance between the hubs of the wheels, and is tubular, enclosing a second shaft B¹,
which may be either hollow, or solid, and which also extends the full distance between.
the wheel hubs.
Shaft B, is driven directly through a pinion d, on the motor shaft, and a toothed
wheel d¹, on the shaft B. At one end of the said shaft B is fastened a cup, or cage, G,
which carries, on opposite sides, two bevel pinions g¹, g', which rotate on short studs
fixed in the cup (see Figure 3). The axes of these pinions are in the same line,
radially of the shaft B. Engaging these pinions on one side is a bevel toothed
wheel G which is keyed to the flange of the hub H, of the wheel, the said hub being
a tubular box which encloses the compensating driving mechanism, and is supported
at the inner end by the ring, or closure, H¹. On the other side of the pinions g',
from the bevel wheel G³, is another bevel wheel G2, keyed to the inner shaft B¹, which
is loose in the tubular shaft B.
At the other side of the vehicle the wheel hub H2, (Figure 1), is keyed to the inner
shaft B, and turns loosely on shaft B. Thus the rotation of the shaft B, carries the

page_text: pinions g, of the compensating mechanism in a circular path around the axis of the
shaft, and these pinions, engaging with the bevel wheels G1 G2, rotate them in the same
direction, the pinions not ordinarily rotating themselves, but acting simply as driving
keys. The bevel wheel G¹, being keyed directly to hub H, imparts motion to that
driving wheel, while the gear G2 through the intermediary of the inner shaft B¹,
imparts motion to the hub H2 of the other driving wheel. When the vehicle changes
the direction of its line of travel, tending to accelerate the motion of one wheel and
correspondingly diminish that of the other, the pinions g¹ by turning on their axes
will permit this differential motion.
The principal advantages of this construction are that the driving shafts extend
continuously from side to side of the vehicle affording maximum strength, that the
compensating mechanisin is readily accessible upon removal of the wheel in the hub
of which it is enclosed, that it occupies no extra space and requires no special housing,
and that it is characterized by simplicity of construction and requires a relatively small
number of parts.
A
Keyed on the driving-shaft and adjacent to the driving wheel is a brake
drum d²; mounted, at its lower end, upon the housing D2 is a bell-crank lever R,
having two studs, r, r, Figure 6, extending therefrom, and a brake strap or band Ri
passes round the drum d2 and is attached at its respective ends to these studs r.
connecting rod passes forward from the upper end of the lever R to a lever under
control of the operator, so that by operating this lever, the rod draws the upper end
of the brake-lever R forward, and the studs on this lever are also carried forward,
each stud pulling forward its respective end of the brake-band. The result is that
the band is applied with double force and rapidity around the greater portion of the
periphery of the drum.
The steering of the vehicle is effected through the front wheels, which, as usual,
are loose on their axles. The hubs of the wheels are pivoted, so as to turn for the
purpose of steering, on a vertical axial line in the plane of the tread of the wheel. This
construction is common in vehicles of this class and its advantages are well understood.
There are, however, according to this invention, special features of construction in
the steering heads as follows:-Figure 2 illustrates a type of steering head designed
especially for heavy vehicles, while Figure 5 illustrates a simplified construction
suitable for lighter vehicles. The main features of the two forms are the same.
Referring first to Figure 2, K represents a cylindrical box, or casing, into which the
end of the axle A extends, and to which it is pivoted, by means of a vertical bolt, K',
in the plane of the tread of the wheel. At the end of the axle, on its upper side, is a
circular ball-race surrounding the bolt K¹, and containing the balls k, on which a
conical shoulder ¹ on the bolt K¹ bears. A second set of balls 2, is interposed
between the axle and the box K, the upper bearing surface in contact with these balis
being conical,
The bearing surfaces or shoes are of suitable hardened metal. It is to be observed
that the function of the balls is not only to support the weight bearing upon the
parts, but also to hold the pivot bolt K¹ centrally in its aperture free from contact
with the axle except at the ball-bearing surface, and further to permit taking up
wear and end-thrust by tightening up the nuts on bolts K¹. To the box K is attached
an arm m, an arm m³ forming therewith a right-angled lever of which the bolt K¹ is
the pivot. The lever m m¹ is connected to the steering handle through connections
hereafter described.
The box K is enclosed by the cylindrical hub N, ball-bearings being interposed
between these parts, so that the hub rotates on the box K. The hub carries two
annular ball races n n¹. Each of these is a trough shaped ring which is inserted into
the open sides or ends of the cylindrical hub and driven up against a shoulder or
stops n² on the inner surface of the hub. The race n is held in place by a threaded
disc N¹ screwed into the hub closing that side thereof. The race n is similarly held
in place by a threaded ring N2 through whose central opening the axles A and arm ma
pass. Each race has an annular ball-retainer and dust excluder n³, made of thin
sheet-metal L-shaped in cross-section. The bearings on the box are hard steel

page_text: rings n n having inclined bearing surfaces. The balls and bearing surfaces are, as
shewn, so arranged as not only to form bearings for the hub, but also to permit of
taking up wear and end thrust by adjustment of the relative positions of the races
and bevelled bearing surfaces. The parts are easily assembled and the steering head
as a whole is but little liable to derangement.
The construction shewn in Figure 5 differs from that in Figure 2 only in so far
that, for the ball bearing swivel joint between the axle and steering arm, are
substituted cone bearings formed by conical pointed pins K2 (one of which is shewn
in the drawing) entering conical sockets in the axle A. This construction operates
well with light vehicles.
The foregoing description applies to both of the forward wheels. The arms m m¹
of the steering levers are connected together by a cross-bar m² pivoted to each, so
that the arms m¹ move together. One of the arms m¹ is prolonged and to its
prolonged end is connected (preferably by universal joint) a link o, the opposite end
of which is pivoted to a crank arm o¹ attached to and operated by a vertical spindle
or steering-arm 02, which has at its upper end an operating handle. On turning the
spindle o' the link o is moved longitudinally in one direction or the other, thereby
tilting the angular steering levers m m³, one of them directly and the other through
the cross-bar m². The positions assumed by the wheels and steering gear in making
a turn in one direction are indicated by dotted lines. It is to be noticed that, in
moving in a curved line, the two wheels of a pair tend to assume different angles, the
inner wheel, which travels on a curve of shorter radius than that of the outer wheel,
assuming the greater angle of inclination. The construction described permits of the
necessary accommodation for this condition, and it will be seen by observing its
operation that, whichever way the vehicle turns, the inner wheel will make the greater
deflection. This is due to the relative lengths of the arms m and m³, measuring the
latter from the joint p or p¹, where it connects with the cross-bar m², to the angle it
makes with the arm m. Assuming the parts to be in the positions indicated by
dotted lines it will be seen that the arc on which joint p¹ moves, is such as to have
brought the joint nearer to the axle, while joint p on the contrary has moved further
from the axle and nearer to the normal plane of the tread. Consequently the inner
wheel which moves on the curve of shorter radius has the greater inclination.
Obviously the greater the movement of the steering levers the greater will be the
difference of inclination, and if the steering spindle be turned in the opposite
direction the conditions will be reversed.
Experiment shews that the proper operation is best attained when an imaginary
drawn from the pivot K₁ to pivot p makes with arm m³ an angle of
22 degrees.
line
An advantage of the steering gear described above is its freedom from cog-gearing,
and from liability to derangement by the motion and jolting of the vehicle."
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. An approximately rectangular running gear frame for motor vehicles in which
the two axles are capable of independent vertical play while being retained in
substantially parallel vertical planes by means of the side bars, substantially as
hereinbefore described.
2. A running-gear frame for motor vehicles comprising the front and rear axles
and two side bars connecting them, the said bars being each attached to the rear
axle by a universal joint, and one of the bars being secured rigidly to the front axle
while the other is secured thereto by a swivelling connection, substantially as
hereinbefore described.
3. An approximately rectangular running gear frame, for motor vehicles, in which
one of the side bars is connected rigidly to the front axle, while the other is
connected thereto loosely, substantially as hereinbefore described.

page_text: 4. The combination of the rotating axle having a collar near each end, the
relatively stationary casing surrounding the axle and having an enlargement at each
end, the ball-bearings situated within the enlargements and against the outer side
of the collars, and means for tightening the balls up against the collars, substantially
as herein before described.
5. In a running-gear frame of a motor vehicle, the combination with the revolving
shaft or axle, and the relatively stationary casing surrounding it and having a
spherical seating near each end, of the side bars mounted to turn freely upon the
seatings and connected at their forward ends to the fore axle, the forward portion
of the casing being supported from the frame, substantially as herein before
described.
6. The wheel having a compensation-gearing within its hub and upon one end of a
continuous shaft, or axle, substantially as herein before described.
7. The combination with two axles located one within the other, of a hub at one
end of the said axles enclosing a compensating-gearing, the said gearing comprising
a bevel-wheel secured on the inner axle, a bevel-wheel on the hub, and bevel pinions,
mounted to rotate upon a support rigidly connected to the outer axle, and arranged
between and gearing with the bevel-wheels, substantially as hereinbefore
described.
8. The combination of two independently revoluble axles, one inside the other, and
both extending continuously from side to side of the vehicle, substantially as
herein before described.
9. The combination of the brake-drum fast on the driving-shaft, the brake-lever
mounted on the casing that surrounds the driving-shaft and driving-gear, and the
brake-band passed around the drum and secured to the lever, substantially as
herein before described.
10. The hub having race-ways for ball bearings near each end, the balls in the
race ways, and the annular ball-retainers, in combination with the cylindrical box
mounted upon the end of the axle by a vertical pivot, and an arm for turning the
box and with it the hub, substantially as herein before described.
11. The combination with a hub and a cylindrical box upon which it is mounted
to rotate freely, of the axle, a bolt passing through the axle and the box and pivoting
the latter upon the former, the said bolt having a conical shoulder near its upper end,
and two sets of ball-bearings, one between the said shoulder and the upper face of the
axle, and the other between the the lower face of the axle and the cylindrical box,
substantially as herein before described.
Dated this 7th day of March 1000
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.