Improvements in Gas and like Engines.
Year: 1893

page_text: Date of Application, 24th May, 1893
Complete Specification Left, 21st Mar., 1894-Accepted, 21st Apr., 1894
PROVISIONAL SPECIFICATION.
Improvements in Gas and like Engines.
We, JOHN WILLIAM HARTLEY of Kay Park, Kilmarnock, Engineer, and
JOHN KERR of the Firm of Dick, Kerr & Co. Limited of Britannia Engineering
Works, Kilmarnock, Engineer, both in the County of Ayr do hereby declare the
nature of this invention to be as follows:-
In starting gas or the like engines we introduce steam under considerable
pressure into the explosion space by means of a suitable cock which has ample area
for admitting the steam rapidly. This cock or valve is operated either
automatically or by hand. We admit the steam each stroke or each alternate
stroke and thus drive forward the piston until the engine has attained sufficient
speed for starting to work. We disconnect the air and gas inlet valve (which
thereby remains closed) by sliding the lifting cam axially along the side shaft or in
other suitable manner & we sometimes in case of gas engines working on the
Otto cycle slide the ordinary exhaust cam along the shaft & replace it with a two
lift cam which lifts the exhaust valve once at each revolution of the engine instead
of every alternate revolution as in ordinary working. By this latter device we
obtain an impulse each revolution of the engine & we more easily get up the
required speed. In engines using Dowson gas we take the steam from the boiler
used for generating the gas and arrange a receiver close to the cylinder or we may
use steam from other source. In a double acting Otto cycle engine we introduce
the steam at one end only of the cylinder in the manner described the other end
operating with gas in the usual manner. As soon as the engine is under way we
replace the cams in their normal position & the engine goes on to work in the usual
manner, We sometimes employ compressed air in the manner herein described for
steam. In operating the steam cock automatically we sometimes make use of the
double lift cam which operates the exhaust lever, the cam roller being arranged to
open the valve or cock during the outstroke of the piston. In constructing cams
for lifting gas engine valves it is of advantage that they be easily & readily
removable & in the case of such cams as are revolved upon the shaft by a helix
we also arrange them to be carried in ball bearings whereby they can be controlled
by the governor with the least amount of friction. We fix on the side shaft upon
one side of the loose cam a fast collar having on its side face a rebate or groove
concentric with the axis of the shaft. This rebate forms one portion of the seat
for the balls to work upon. A second corresponding ring adjoins & forms the
opposing seat for the balls. The face of this second ring furthest from the ball
bearings we groove or rebate & the cam proper we cut in halves & arrange with
tongue or projection fitting into the rebate or groove in the second named loose ring
a corresponding ring to the second ring follows and retains the two halves of the
removable cam in position the balls and the seating being on the further side of
the ring from the removable cam. The other side of the seating may be formed in
the fast cam or a ring suitable for the purpose. Sometimes we dispense with ball
bearings in the case of revolving cams. In case of fixed cams in halves ball
bearings & the outside collars are not needed but the inner collars are then fixed to
the shaft. By sliding away one of these rings the cam can be at once removed
without taking down the shaft.
Dated this 20th day of Mon 1902
J. W. HARTLEY.
JOHN KERR.

page_text: VODIL LUID
Improvements in Gas and like Engines.
We, JOHN WILLIAM HARTLEY, of Kay Park, Kilmarnock, Engineer, and
JOHN KERR, of the Firm of Dick, Kerr & Co. Limited, of Britannia Engineering
Works, Kilmarnock, Engineer, both in the County of Ayr, 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 :—
Our invention relates to gas and like engines and comprises-an improved method
of starting such engines by steam; and an improved construction of cam suitable
for gas engines so arranged as to allow the cam or cams to be removed from the
cam shaft without dismounting the said shaft.
Referring to the three accompanying sheets of drawings
Figure 1 is a section of a valve suitable for starting with steam pressure.
Figure 2 is an elevation part section taken in a position at right angles to that
shown in Figure 1.
Figure 3 is a side elevation of the combustion chamber end of a gas engine
cylinder, showing the steam starting valve in position, and also showing the mode
of altering the positions of the cam rollers to enable the start to be made.
Figure 4 is a plan corresponding to Figure 3.
Figure 5 is a section showing our divided removable cam.
Figure 6 is an end elevation corresponding to Figure 5.
Figure 7 is a section similar to Figure 5 showing a cam suitable for operating by
governor having ball bearings.
Figure 8 is a section similar to Figure 7 also showing a cam intended to be
operated by governor but without ball bearings.
In starting gas or the like engines according to our invention, we introduce
steam under considerable pressure into the explosion space of a cylinder S by
means of a suitable cock or valve Figures 1, 2, and 4, which has ample area for
admitting the steam rapidly.
This cock or valve contained in the casing D is operated either automatically or
by hand.
We admit the steam each stroke of the piston or each alternate stroke and thus
drive forward the piston until the engine has attained sufficient speed for starting
to work. The valve shown at Figures 1 and 2 is very suitable for starting by
steam; A is the valve, which retains steam pressure obtained from any suitable
source and when opened permits the steam to flow from B into the passage C
which leads to the gas engine cylinder. The nuts A' A on the valve stem are
adjusted to allow the starting lever A to operate the valve; the nut A* is screwed
back against the bridge E when it is desired to lock the valve A after the engine
has started.
We disconnect the air and gas inlet valve (which then remains closed) by
sliding the lifting cam M which operates the said valve, axially along the side
shaft F, or we disconnect in other suitable manner; we sometimes in the case
of gas engines working on the Otto cycle slide the ordinary exhaust cam along
the shaft and replace it with a two lift cam which lifts the exhaust valve once
at each revolution of the engine, instead of every alternate revolution as in
ordinary working. By this latter device we obtain an impulse every revolution
of the engine and we more easily get up the required speed. For this purpose
we may adopt the arrangement shown at Figures 3 and 4. M is the gas and
air inlet cam which is controlled by a sliding rod K; the said rod K also controls
levers carrying rollers G' H', the said levers being arranged to slide on the
fulcrum rod L. The alteration of the position of the levers relatively to the
cams G H on the shaft F determines which of the said cams shall operate

page_text: the exhaust valve, and so allows the exhaust valve to be opened on each backward
stroke of the piston or every second backward stroke as may be desired. In
engines using Dowson gas we take the steam from the boiler used for generating
the gas and arrange a receiver close to the cylinder, or we may use steam from
other source.
In a double acting Otto cycle engine we introduce the steam at
one end only of the cylinder in the manner described, the other end operating with
gas in the usual manner. As soon as the engine is under way we replace the
cams or rollers in their normal position by a sliding rod such as K Figures 3
and 4, and the engine goes on to work in the usual manner.
As shown on the drawings the starting lever A³ is operated by hand, but we,
may connect to so as to be operated by a cam on the cam shaft F.
In operating the steam cock automatically we sometimes make use of the double
lift cam which operates the exhaust lever, the cam roller being arranged to open
the valve or cock during the out stroke of the piston.
In constructing cams for lifting gas engine valves (Figures 5, 6, 7 and 8) it is
of advantage that they may be easily and readily removable, and in the case of
such cams as are revolved upon the shaft by a helix, we arrange them to be carried
in ball bearings, whereby they can be controlled by the governor with the least
amount of friction. We fix on the side shaft F (Figures 5 and 6) upon one side
of the loose cam, a collar having on its side face a rebate or recess O', concentric
with the axis of the shaft and on the other side of the said loose cam we fix to
the shaft another fixed collar O² which we sometimes attach to the loose cam N
by a dowel pin Q. The cam N we divide into two parts N N¹ shown more clearly
at Figure 6, and we form a projecting boss to enter into the recess O¹ in the
collar O. To take out the cam it is only necessary to slide back the collar O after
unscrewing its set screw and then the two parts of the cam N N' are easily removed
from the shaft.
When we desire to use ball bearings in order to allow the governor to act upon
the cam or cams to rotate them round the shaft by means of a sliding piece with a
helical thread as described in Specification No. 3971 of 1893 of a Patent already
granted to us, we arrange as shown at Figure 7. O and O' are fixed collars;
N N' and N' N³ are cams made in two parts as shown at Figure 6.
In this case,
however, the rebate or recess 0¹ is dispensed with and the grooves such as 0' 0³
take their place, and so ball bearings R are formed. The balls R work in opposing
grooves in the faces of the collars Ŏ and O' and the faces of the cams N N',N' N³.
The balls R hold together the two halves or parts of each cam so that they cannot
be taken off until a collar such as O is caused to slide along the shaft F. While
in position, however, the balls allow of perfect freedom of rotation by the governor.
Sometimes we dispense with ball bearings in the case of such revolving cams. Such
an arrangement is shown at Figure 8 where two outside fixed collars have grooves
or rebates as described, and the two parts each N N', N' N³, N N° are arranged
to fit into each other by alternate concentric projections and recesses. By this
arrangement also the said divided cams may be readily removed by sliding the
collar O along the shaft.
In case of fixed cams in halves ball bearings and the outside collars are not
needed; the inner collars are then fixed to the shaft. By sliding away one of
these collars or rings the cam can be at once removed without taking down the
shaft.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The method of starting a gas or like engine by means of steam under pressure
admitted to the combustion space of the said engine by a suitable valve, operated
either automatically or by hand, thereby applying such a number of steam impulses
as will enable the engine to get up a sufficient speed for working with the ordinary
cycle as described.

page_text: 2. In a gas or like engine adapted to be started by steam as herein specified the
valve gear for throwing in and out of action the gas and air inlet valve, and for
causing the exhaust valve to be operated every back stroke or every second back
stroke as desired, substantially as described for the purpose specified.
3. The combination with a gas or like engine adapted to be started by steam
under pressure of the steam boiler of a gas producing plant which supplies gas to
the engine for the purpose of supplying steam for starting, substantially as
herein before described.
4. For gas and like engines a cam constructed in separate parts united by means
of collars which can be fixed to the cam shaft so that on sliding one or both of the
said collars along the shaft, the cam may be removed without dismounting the shaft,
substantially as herein before described.
5. For gas and like engines, cams adapted to be controlled by governor and
capable of rotation round the shaft, the said cams being divided and retained by
collars and with or without ball bearings, substantially as herein before described
with reference to Figures 7 and 8 of the accompanying drawings.
6. A gas or like engine constructed substantially as described with reference to
Figures 1 to 4 of the accompanying drawings, and operating as, and for the purpose
specified.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and 13, Temple Street,
Birmingham, Agents for the Applicants.