Improvements in Gas Motor Cars.
Year: 1893

page_text: Date of Application, 4th Dec., 1893
Complete Specification Left, 10th Aug., 1894-Accepted, 15th Sept.,
1894'
Improvements in Gas Motor Cars.
I, HENRY PERCY HOLT, of 22 Chancery Lane, in the County. of London,
Engineer, do hereby declare the nature of this invention to be as follows:-
As in gas locomotives it is desirable to work the gas motor engine at nearly
constant speed, gearing of at least two proportions and suitable clutches have to
be provided whereby the car can be driven at either of two speeds and it is also of
the greatest importance that the motor should be free to work while the car is
standing still and may not have its speed reduced so much as to endanger its.
stopping in order to avoid the delay and difficulty of retarding it.
My invention is designed to effect the above in cases in which the car is driven
by compressed gas carried in a reservoir or compressed air for the purpose of
vaporizing or spraying liquid fuel.
I make use of clutches on the engine or countershaft each of which consists of,
several plates or discs arranged side by side, the first, third, &c. plates revolving.
with the shaft, the alternate plates, namely the second, fourth &c. revolving with the
boss of a toothed wheel which is free to revolve on the shaft. Both sets of plates.
can slide a little longitudinally. The first plate is pressed against by a ring in
contact with a flexible diaphragm, covering the face of a hollow disc fixed on the
shaft.
The cavity of this disc behind the diaphragm communicates by a bore in the
shaft with a valve (under the control of the driver) by which it can be put in.
communication either with the gas reservoir or with the gas supply pipe of the
engine, or with the atmosphere.
There are two sets of clutches as described acting on two wheels of different
diameters gearing with wheels on a parallel countershaft.. The valve above.
mentioned is so arranged that in one position it cuts both of the clutch discs off
from communication with the gas reservoir. relieving the pressure on both
diaphragms and consequently leaving both sets of plates loose, so that neither of
the wheels on the countershaft is driven. In another position of the valve, one
diaphragm is relieved from pressure but the gas pressure acts on the other
diaphragm pressing the adjacent plates closely together, so that the one wheel is
loose and the other wheel is driven and drives the parallel shaft at the one speed.
In a third position of the valve, the other clutch is brought into action driving the
parallel countershaft at the other speed.
It will be seen that in this way the pressure of the gas or air is made to work
the clutches and may still be used in the engine. The details of the mode of
effecting this may be varied without departing from this invention.
my
In some cases I connect the valve described, or it may be another valve, to a
governor in such a manner that when the speed of the gas engine is too low, the
clutch diaphragms are relieved from pressure, leaving the engine more or less free.
from load, until it regains its speed.
Dated this 4th day of December 1893.
ABEL & IMRAY,'
Agents for the Applicant

page_text: improvements in Gas Motor Cars.
I, HENRY PERCY HOLT, of '22 Chancery Lane, in the County of London,
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 :-
As in gas locomotives it is desirable to work the gas motor engine at nearly
constant speed, gearing of at least two proportions and suitable clutches have to be
provided, whereby the car can be driven at either of two speeds; and it is also of
the greatest importance that the motor should be free to work while the car is
standing still, and may not have its speed reduced so much as to endanger its'
stopping in order to avoid the delay and difficulty of starting it again.
My invention is designed to effect the above in cases in which the car is driven
by compressed gas carried in a reservoir, or compressed air for the purpose of
vaporizing or spraying liquid fuel.
I make use of clutches on the engine shaft or a counter-shaft driven by the
engine shaft, each of which consists of several plates or discs arranged side by
side, the first, third &c. plates revolving with the shaft, the alternate plates, namely
the second, fourth &c. revolving with the boss of a toothed wheel which is free to
revolve on the shaft.
Both sets of plates can slide a little longitudinally. The first plate is pressed
on by a flexible diaphragm, covering the face of a recessed disc fixed on the shaft. "
The recess of this disc behind the diaphragm communicates by a bore in the
shaft with a valve (under the control of the driver) by which it can be put in
communication either with the reservoir of compressed gas or with the gas supply
pipe of the engine, or, when compressed air is used, the recess can be put in
communication with the reservoir of compressed air, or with the atmosphere.
"There are two sets of clutches as described acting on two wheels of different
diameters gearing with wheels on a parallel countershaft. The valve above'
mentioned may be either a slide or a partially rotating valve governing suitable
ports so arranged that, in one position it cuts both of the clutch discs off from
communication with the gas or air reservoir relieving the pressure on
diaphragms and consequently, leaving both sets of plates loose, so that neither of
the wheels on 'the countershaft is driven. In another position of the valve, one'
diaphragm is relieved from pressure, but the pressure is made to act on 'the other'
diaphragm pressing the adjacent plates closely together, so that the one wheel is
loose and the other wheel is driven and drives the parallel shaft at the one 'speed.
In a third position of the valve, the other clutch is brought into action driving 'the
parallel countershaft at the other speed.
both'
It will be seen that in this way the pressure of the gas or air is made to work the
clutches and may still be used in the engine. The details of the mode of effecting
this may be varied without departing from this my invention.
In some cases I connect the valve described, or it may be another valve, to a
governor in such a manner that when the speed of the gas engine is too low, 'the
clutch diaphragms are relieved from pressure leaving the engine more or less free
from load, until it regains its speed.
Fig: of the accompanying drawings is a longitudinal section of the shaft and
clutchers.
Fig. 2 is a longitudinal section of a modified construction, and Fig. 3 is a
transverse section on Z Z of Fig. 2.
Dis the shaft on which are fixed the two recessed discs A, B, each having a
flexible diaphragm fixed in front of it. The space between the diaphragm of A
communicates by a lateral passage a and a bore in the shaft D with a pipe a¹ in a

page_text: larger bore of the shaft. The space behind the diaphragm of B communicates by
a lateral passage b with the annular space b¹ around the pipe a¹. a¹ and b¹ are
connected by suitable packed unions to pipes leading to two of the ports of the
valve above referred to. On the shaft D are fitted free to revolve the two toothed
wheels d' d' of different diameters.
Into notches formed in the bosses of these wheels project teeth of discs d³.
To the peripheries of the discs A and B are bolted flanged discs E and F having
their flanges internally notched to receive teeth projecting from discs d' and d³.
When the pipe a' is by the valve put in communication with the store of fluid
under pressure, and the space 6' with low pressure fluid, the diaphragm in face of A
is distended pressing closely together the discs E d³ d³ d³ and d', and thus causing
such friction that the discs E, d' and d', which revolve with A, cause the discs d³ d³
also to revolve and drive the wheel d¹, the discs adjoining B being loose.
When a is, put in communication with low pressure fluid, the friction discs
adjoining A are left loose, and the wheel d' is not made to revolve. In like
manner by putting 6' in communication with the high or low pressure fluid the discs
adjoining B are made to drive or to release the wheel d². As shewn in Figs. 2
and 3. Instead of employing flexible diaphragms in front of discs A and B as
above described, I fix on the shaft D collars d with bosses on which are fitted with
keys but free to slide discs d' and between d³ and do I place a pair of discs d' having
between them a coil of flexible pipe de communicating with the respective ports of
the valve. The coil do and the discs d' which are surrounded by a ring are prevented
from revolving by a link d' attached to the frame of the car. In order to reduce
friction, a number of balls are inserted between the discs d' and the faces of d³
and d. The friction discs d³ and d' effect the clutching or unclutching of the
wheels d d according as the coil d³ is distended or not by the fluid pressure. When
the recesses behind the diaphragms or the tube coils are relieved from pressure, the
friction discs are released by springs such as S. Although I have shewn several
sets of friction discs pressed against one another, a single set may in some cases
suffice to cominunicate this driving power.
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. The herein described method of connecting the varying speed gears of a gas
motor car to the engine or disconnecting them from the engine by means of
friction clutches operated by the pressure of the compressed fluid stored on the car
for working the engine.
2. For operating as set forth in the preceding claim, apparatus consisting of the
speed gears and friction clutches arranged on a shaft between two flexible
diaphragms, either or neither of which can be distended by the fluid under pressure,
substantially as described.
3. The modified arrangement substantially as described in which coils of flexible
pipe held between stationary discs are substituted for the diaphragms referred to in
the preceding claim.
Dated this 10th day of August 1894.
ABEL & IMRAY,
Agents for the Applicant.