Improvements in Variable and Reversible Intermediate Gear for Motor Cars.
Year: 1897

page_text: Date of Application, 17th Feb., 1897
Complete Specification Left, 19th May, 1897-Accepted, 10th July, 1897
PROVISIONAL SPECIFICATION.
Improvements in Variable and Reversible Intermediate Gear for
Motor Cars.
I, FRANCIS GWYN GRIFFITH of Llansannor House, near Cowbridge, in the
County of Glamorgan, Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to a mechanism adapted to control the motion of the
driving gears of motor cars and is especially adapted to the high speed oil
engines at present in use.
It is well known that engines worked by explosion of gases, such as oil motors,
are started with difficulty and cannot be reversed. Therefore they must be run
continuously and at about the same speed, whether at work or not.
In carrying my invention into effect I apply a mechanical arrangements to
convey the power from the continuously running motor engine to the driving axle
of the carriage. This mechanism is capable, by the movement of hand or foot levers,
to control the forward or backward travel of the car with great ease and without
stopping the motor or interfering with its revolutions. The same levers act as
brake levers. In describing the action of the mechanism, I will commence with
those parts immediately connected to the motor.
Upon its driving shaft, I place a grooved cam or eccentric which runs in an
oblong frame pivotted at its lower end. Along one side of the frame a groove or
bar is formed, having a sliding block, adapted to travel along its entire length.
To this sliding block, a connecting rod is attached and that conveys the motion
from the oblong frame to the driving gear upon the axle, by the following means.
At the opposite end of the connecting rod, a slot is provided, so that it can travel
or reciprocate transversely of the driving axle.
Ratchet levers are applied to the reciprocating end of the connecting rod. These
levers oscillate upon the driving axle and have fixed pins formed upon their sides.
These pins work in transverse slots in the connecting rod end, so that when the
connecting rod is reciprocated, the ratchet levers rock upon the axle.
Running upon a sleeve on the axle and fitted with a suitable key or feather,
is a pair of ratchet wheels or detents attached to the ends of the ratchet. Pawls
on the ratchet levers engage with the teeth of the ratchet wheels as the connecting
rod is reciprocated and cause the axle to revolve through a portion of a circle.
The ratchet wheels are fixed at a slight distance from each other. The pawls
are fixed in opposite directions and hang when the axle is not revolving, in an
intermediate position between the two ratchet wheels.
The wheels themselves, as before stated, slide upon the axles, this movement
being controlled by a pin working in a grooved disc keyed to the sleeve and
operated by suitable levers which can be applied, in the case of motor cars, by
the driver pressing the levers with his feet, so that either of the wheels can be
brought into action with either of the pawls on the ratchet levers.

page_text: brake levers. In describing the action of the mechanism, I will commence with
those parts immediately connected to the motor.
Upon its driving shaft, I place a grooved cam or eccentric which runs in an
oblong frame pivotted at its lower end. Along one side of the frame a groove or
bar is formed, having a sliding block, adapted to travel along its entire length.
To this sliding block, a connecting-rod is attached and that conveys the motion
from the oblong frame to the driving gear upon the axle, by the following means.
At the opposite end of the connecting rod, a slot is provided, so that it can travel
or reciprocate transversely of the driving axle.
Ratchet levers are applied to the reciprocating end of the connecting-rod. These
levers oscillate upon the driving axle and have fixed pins formed upon their sides.
These pins work in transverse slots in the connecting rod end, so that when the
connecting-rod is reciprocated, the ratchet levers rock upon the axle.
Running upon a sleeve on the axle and fitted with a suitable spline or feather,
is a pair of ratchet wheels or detents attached to the ends of the ratchet. Pawls
assisted by springs, on the ratchet levers engage with the teeth of the ratchet
wheels as the connecting-rod is reciprocated and cause the axle to revolve through
a portion of a circle.
The ratchet wheels are fixed at a slight distance from each other. The pawls
are fixed in opposite directions and hang when the axle is not revolving, in an
intermediate position between the two ratchet wheels.
The wheels themselves, as before stated, slide upon the axles, this movement
being controlled by a pin working in a grooved disc keyed to the sleeve and
operated by suitable levers which can be applied, in the case of motor cars, by
the driver pressing the levers with his feet, so that either of the wheels can be
brought into action with either of the pawls on the ratchet levers.
When one of the ratchet levers is in gear the car goes forward, when the
other is in gear, the car goes in the opposite direction; and when neither of them
is in gear, the car stops.
The sliding block upon the oblong frame is capable of being raised or lowered
so that the effect of the stroke of the cam on the motor shaft, can be multiplied
or diminished according to the position of the block upon the above mentioned
groove or bar. To control this motion, an L-shaped lever is connected by a link
to the sliding block. When the block is placed near the centre of oscillation of
the frame, there is no movement conveyed to the connecting rod; but when the
block is raised to the opposite extremity of the frame, the movement upon
the connecting rod is at its maximum and the axle revolves with each stroke to the
extent provided for, by reason of the leverage of the frame, .e., the distance of
the sliding block from the centre of the oscillation of the frame.
Any intermediate leverage can be obtained according to the position of the
sliding block upon the groove or bar, so that the car can be started gradually by
the operator pushing the lever over until the block reaches the portion of the
groove or bar farthest away from the fulcrum, thus enabling a heavy vehicle to
he started with great power and low speed and the speed to be increased when well
under way. The same lever arrangement for placing the block downwards and
near the centre of oscillation, also actuates an arrangement of brake gear, so that
the operation of throwing the rapid movement out of gear, by means of the sliding
block also puts the brake on.
When this arrangement is applied to a tram car, the levers can be attached at
either end of the latter, so that the mechanism can be controlled at any point.
In the accompanying drawings
:-
Figure 1 is a side elevation of the arrangement.
B is
A is the shaft of the motor engine, which may be the shaft of the engine
itself, or a countershaft driven by suitable gearing, from the engine shaft, so that
it may be run at a very much lower speed, than that of the driving engine.
a crank pin, or if preferred it may be made in the form of an eccentric, this
crauk, pin is fixed to a suitable crank C upon the shaft A. D) is a fixed piu or

page_text: motion from the crank pin B, to the swinging frame E, and is for the same
purpose as the slot F in Figure 1. The reference letters throughout the drawings
apply to different views of the same parts.
Fig. 4 is an end view of Fig. 3.
A summary of the invention would be as follows:-
The motor is fitted with a grooved cam which runs in an oblong frame pivoted
at lower end which carries a groove or bar to which is attached a connecting rod
which slides up and down on same.
The connecting rod is provided with slots at other end which actuate a double
action ratchet gear fitted on a hollow spindle which works on a driving shaft
provided with a spline or feather. On the hollow spindle is fixed a grooved wheel
which is actuated by reversing lever.
A double L lever pushes up or down connecting-rod for increasing or reducing
speed. After the lever is pushed down to the lowest point of speed, the other end
of the L pulls up a chain or slotted connecting-rod to which is attached a cross-
head actuating one or more band brakes. The lever L when used in tram cars
is connected to another lever at the other end of tram so that the driver can work
the same from either end, he having first shifted the reversing lever.
The reversing lever when used in auto-cars is provided with a T head which
forms a foot rest, one foot being placed on each side of it, so that if either foot be
pushed forward the motion will be reversed one way or other, but if the T be kept
parallel the ratchets are idle. Or the reversing lever can be worked by hand if
preferred.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is :-
1. In combination with a motor-driven vehicle, mechanism for controlling the
travel of the vehicle in either direction independently of the constant revolutions
of the motor, consisting of an oblong frame pivoted at one end, a longitudinal
slot therein and a groove or bar thereon, substantially as and for the purposes
described and shewn.
2. In combination with a motor-driven vehicle, mechanism for controlling the
travel of the vehicle in either direction independently of the constant revolutions
of the motor, consisting of an oblong frame, with a longitudinal slot therein in
which slides a block actuated by a cam, crank, or eccentric attached to the motor,
a bar or groove on the said frame and a connecting rod, one end of which is
moveably attached to said bar or groove, the other end being forked and slotted
substantially as and for the purposes herein described and shown.
3. In combination with a motor driven vehicle, mechanism for controlling the
travel of the vehicle in either direction independently of the constant revolutions
of the notor, consisting of an oblong frame pivoted at one end, with a longitudinal
slot therein in which slides a block actuated by a cam, crank, or eccentric attached
to the motor, a bar or groove on the said frame, a connecting-rod, one end of which
is moveably attached to said bar or groove, the other end being forked and slotted
and the double action ratchet gear on hollow spindle working on a splined driving
shaft, actuated by the said slots, and grooved wheel on said hollow spindle actuated
by a reversing lever, substantially as and for the purposes described and shewn.
4. In combination with a motor driven vehicle, mechanism for controlling the
travel of the vehicle in either direction independently of the constant revolutions
of the motor, consisting of an oblong frame pivoted at one end, with a longitudinal
slot therein in which slides a block actuated by a cam, crank, or eccentric attached
to the motor, a bar or groove on the said frame, a connecting-rod, one end of which
is moveably attached to said bar or groove, the other end being forked and slotted,
the double action ratchet gear on hollow spindle working on a splined driving
shaft, actuated by the said slots, and grooved wheel on said hollow spindle
actuated by a reversing lever, and the means provided for increasing or reducing