Improvements in or in connection with the Ignition Arrangements of Gas and Oil Motor Engines.
Year: 1899

page_text: Date of Application, 13th Oct., 1899
Complete Specifi cation Left, 13th July, 1900-Accepted, 15th Sept., 1900
PROVISIONAL SPECIFICATION.
Improvements in or in connection with the Ignition Arrangements of
Gas and Oil Motor Engines.
:
I, FREDERICK WILLIAM LANCHESTER, of 53, Hagley Road, Edgbaston, in the
City of Birmingham, Engineer, do hereby declare the nature of this invention.
to be as follows:-
This invention relates to improvements in the electrical ignition arrangements
of gas and oil motors and more particularly to the arrangement of an electrical
generator for the production of the current necessary for the ignition spark.
The objects of my present invention are firstly to so arrange a dynamo-electric
generator that it is driven at a sufficient speed when starting the motor by hand
and secondly to ensure a practically constant potential when the motor is running.
In one mode of constructing and arranging a dynamo in accordance with my
present invention, I so design the dynamo that the preponderance of the magnetic
field is on one side of the armature so that there is a "pull" on the armature in
a sideways direction, the armature is mounted in bearings carried in a frame
capable of a certain amount of movement and a spring is provided to counteract
the effect of the magnetic pull. The armature shaft is fitted with a friction
pulley which is held in driving contact with the rim of the motor fly wheel by
the aforesaid spring, and the whole apparatus is so proportioned that when the
required potential is reached the magnetic pull rises to such a point that the
pressure of the spring is partially or wholly overcome and the friction drive
commences to slip. It will thus be seen that when the required potential is
reached further increase in the speed of the motor does not affect the working
of the dynamo.
In arranging the speed at which the slipping takes place, that is the minimum
speed of the motor at which the full potential is reached consideration must
be taken of the conditions of running; in all cases this speed should be fixed at
least as low as the minimum speed at which it is desired to run.
For starting the motor by hand I preferably provide the following arrange-
ments. The friction pulley by which the driving of the dynamo usually takes
place operates the dynamo snaft by means of a clutch of the automatic type and
independent mechanism also operating through an automatic clutch is provided
by which the dynamo is driven when the starting handle shaft is rotated, much
higher gear being employed so that with the slow movement of the starting
handle sufficient speed is imparted to the dynamo.
In another arrangement the armature is made of conical form and the magnetic
pull then takes place axially and releases the driving mechanism which in this
case may consist of two discs in frictional contact or a clutch of the coned form.
1000
:
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in or in connection with the Ignition Arrangements of
Gas and Oil Motor Engines.
I, FREDERICK WILLIAM LANCHESTER, of 53, Hagley Road, Edgbaston, in the
City of Birmingham, 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:―
My invention relates to improvements in the electrical ignition arrangements
of gas and oil motors, and more particularly to the arrangement of an electrical
generator for the production of the current necessary for the ignition spark.
One object of my invention is to secure a practically constant potential in a
dynamo-electric generator for producing ignition sparks, while the motor is
running, and a further object is to so arrange the generator that it is driven at
a sufficient speed when starting the motor by hand.
My invention consists in automatically controlling the position of a suitably
disposed and supported dynamo armature in relation to the magnetic field of the
dynamo, that a practically constant potential of the sparking current is main-
tained independently of the variations in the speed of the motor from which
it is driven.
My invention further consists in providing an independent train of mechanism
for starting the motor by hand, consisting of gearing so arranged that a slow
movement of a starting handle will give sufficient speed through the medium of
clutch mechanism to the armature of a dynamo, to give a potential necessary
for producing ignition sparks.
In carrying my invention into effect.
Figure 1 illustrates an end elevation of the armature and pole pieces of a
dynamo, arranged according to one modification of the first part of my invention.
Figure 2 illustrates a side elevation of the armature and pole pieces of a
dynamo arranged according to another modification of the first part of my
invention:
Figure 3 illustrates a side elevation of the gearing for driving the armature by
hand, arranged according to a modification of the second part of my invention.
Referring to. Figure 1, a is an armature spindle on which is mounted an arma-
tube band driving pulley ; the armature spindle a is supported at its ends
in bearings in the arms which are fixed on the spindle e; and arm f having a
hook 9 is also fixed on the spindle e which is free to oscillate in one of the
pole pieces 7 of the dynamo. A hook k is fastened to the dynamo, and between
the hooks g and k is stretched a spring which serves to draw down the lever f
and thus keep the driving pulley in frictional contact with the motor fly
wheel m.
It will be seen from Figure 1 that the armature is so placed between the pole
pieces that there is a preponderance of magnetic field on one side of the axis
of the armature, and that thus when the armature is driven by means of the
fly wheel m through the medium of the driving pulley c, the magnetic field
formed will tend to draw the armature down, against the action of the spring !,
and when a predetermined potential is reached the pulley c will be drawn out
of gear with the fly wheel m and at the same time a stop o on one of the pole
pieces h will present the armature from being drawn too close to the field magnet.
If the potential lowers, the spring will automatically bring the driving pulley c
in contact with the motor fly wheel and the potential will at once be raised again,
so that a practically constant potential is automatically maintained.
Referring to Figure 2, which illustrates another modification of the first part
of my invention, a is an armature spindle, on which is rigidly mounted a coned
armature 6 and a disc clutch p. Loosely mounted on the spindle is a driving

page_text: pulley e having a disc q. The spindle a is supported at its ends in bearings d of
a frame r.
Fixed to the frame r is a field magnet s having pole pieces h, the faces of
which are tapered to correspond with the conical surface of the armature b. A.
spring is mounted on the spindle a and is situated between one of the
bearings d, and the small end of the armature thus acting to press the disc
clutch into contact with the disc clutchy and at the same time keeping the
conical face of the armature a at a fixed distance away from the coinciding:
faces of the pole pieces . The pulley e is in driving contact with the rim of.
the motor fly wheel m. It will be seen that when the conical armature is driven.
by means of the motor flywheel through the medium of the driving pulley c and
the disc clutches and q, the magnetic field formed, will tend to draw the
armature closer to the faces of the pole pieces, and, thus when a predetermined
potential is reached, the disc clutch p will be drawn out of gear with the clutch_q,
against the action of the spring 7. A stop washer is provided on one end of the
spindle to prevent the armature from coming in contact with the faces of the
pole pieces. If the potential lowers, the spring will automatically act to bring
the disc clutch pinto gear with the disc clutch 7, thus the potential will be
rapidly raised again, so that, in this modification, as in the first modification, a
practically constant potential is automatically maintained.
In both these modifications it will be seen that when the required potential
is reached, further increase in the speed of the motor does not affect the working
of the dynamo.
In arranging the speed at which slipping takes place, that is the minimum
speed of the motor at which the full potential is reached, consideration must
be taken of the conditions of running in all cases this speed should be fixed at
least as low as the minimum speed at which it is desired to run.
Referring to Figure 3 which illustrates an arrangement for starting the motor
by hand, according to a modification of the second part of my invention; 2 is a
starting handle which actuates the motor shaft 3 through an automatic clutch:
4 is a toothed disc connected to the starting handle, which actuates a small toothed
disc 5 on a counter shaft 6. On the countershaft is a fixed pulley 7, of much.
greater diameter than the toothed disc 5. which drives a small pulley 8 on the
armature spindle 9 by means of a belt 10, this pulley 8 actuates the armature 9
through the medium of an automatic or positively actuated clutch. The friction
pulley 12 by which the armature spindle 9 is usually driven operates the spindle
by means of a clutch of the automatic type.
In order to start the motor the handle 2 is rotated and by the spur gear 4
and 5 and pulley 7 a high speed is imparted to the small pulley 8 which through
its automatic clutch rotates the armature spindle 9 at a sufficient speed to give
the desired potential. At the same time the handle 2 through its clutch rotates
the motor shaft 3, and the fly wheel through the friction wheel 12 and its clutch
tends to rotate the spindle 9 but at a much slower speed at first than the hand
gear so that the clutch between the wheel 12 and spindle 9 simply slips until the
motor has attained its normal speed, when the clutch between the handle 2 and
motor shaft 3 will automatically disengage and likewise the clutch between 8
and 9, and the rotation of the armature spindle will be taken up by the friction
wheel 12.
In dynamo electric ignition as hitherto employed the current is obtained at
starting by the use of secondary batteries charged from the dynamo when
running.
By the present invention either the use of secondary batteries when starting
the motor by hand is dispensed with, or where not inconvenient, accumulators
may be advantageously retained, and then employed to drive the dynamo, which
in turn operates the starting handle shaft 3 through the independent train of
gearing and thereby automatically starts the motor."
In the latter case the clutch between the armature spindle and the driving

page_text: handle shaft is preferably of the positive type, and under the control of the
driver.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that
what I claim is:-
1. In dynamo-electric ignition apparatus for gas and oil motor engines:
automatically controlling the position of a suitable disposed and supported
armature in relation to the magnetic field of a dynamo, so that a practically
constant potential of the sparking current is maintained independently
of
variations in the speed of the motor from which it is driven, substantially as
described.
2. In dynamo-electric ignition apparatus for gas and oil motor engines, an
armature placed in such a position between the pole pieces of a dynamo that
there is a preponderance of magnetic field on one side of its axis; the armature
being mounted in bearings in a frame which is pivotally supported and spring-
controlled so that when the armature is driven and the predetermined potential
is reached, the pressure on the driving pulley will be varied, the speed and the
potential being thus maintained; substantially as and for the purpose described.
3. In dynamo-electric ignition apparatus for gas and oil motor engines; a
spring controlled, coned armature capable of lateral movement between the
similarly coned pole pieces of a dynamo; the shaft of said armature being
provided with a suitable friction. clutch, so that a predetermined potential when
reached, is maintained practically constant, and independent of variations of the
motors' speed, above the predetermined speed substantially as described.
4. In dynamo-electric ignition apparatus for gas and oil motor engines an
independent train of mechanism for starting the motor by hand, so arranged that
a slow movement of a starting handle will give sufficient speed to the armature of
a dynamo, through the mediuni of a clutch, to give the potential necessary, for
ignition sparking, and so adapted that the motor may be started by means of
the dynamo through the medium of a clutch; the dynamo being run by means of
a secondary battery substantially as described.
5. In dynamo-electric ignition apparatus for gas and oil motor engines; an
independent train of mechanism such as shown in Figure 3, for operating a
dynamo, such that a slow movement of the starting handle 2 will impart
sufficient speed to the armature, through the medium of a clutch, to give the
potential necessary for sparking, substantially as described and shown in
Figure 3.
6. In dynamo-electric ignition apparatus for gas and oil motor engines; a
dynamo, so disposed that the armature may be driven by means of an inde-
pendent train of mechanism through the medium of a positive clutch when
starting the motor, and when the motor is started, that it may be driven by the
motor flywheel, through the medium of a loose pulley and automatic clutch,
substantially as described.
7. The improved combined starting and ignition apparatus herein before
described with reference to the accompanying drawings.
8. The improved hand or automatic starting apparatus hereinbefore described
with reference to Figure 3.
9. The improved ignition apparatus herein before described with reference
to Figures 1 and 2.
1941
ST.... 1000
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.