Improvements in the Igniting Arrangements of Gas and Oil Motor Engines.
Year: 1896

page_text: Improvements in the Igniting Arrangements of Gas and Oil
Motor Engines.
I, FREDERICK WILLIAM LANCHESTER, of Cobley Hill, near Alvechurch, in the
County of Worcester, Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to improvements in the ignition arrangements of gas
and oil motor engines and refers more particularly to igniters in which an
electric spark is employed; this invention has for its object to dispense with the
battery usually employed and to provide a magneto-electric generator without
adding to the weight of the machine.
In one mode of carrying this invention into effect I arrange a permanent magnet
of circular ring form securely attached or embedded in the rim of the fly-wheel
which is made of gun metal or other suitable non-magnetic material, the aforesaid
circular magnet may be built up of a number of lamine or turned in a single
piece and is hardened and tempered in the usual manner, in one arrangement a
segment is cut from the ring and magnetisation is effected to produce north and
south poles at the two extremities but if preferred the ring may be left intact
and consequent poles may be arranged at suitable equidistant points. At suitable
points stationary soft iron armatures are arranged having their poles in proximity
to the rotating magnet and coils are fitted to these armatures to supply the
ignition current to he motor cylinders.
The permanent magnets may form a large proportion of the weight of the
fly-wheel rim or the fly-wheel may be built up with a hard steel magnetised rim,
so that a very massive permanent magnet may be employed without any increase
in the total weight of the motor.
The positions of the fixed armatures are so arranged that a current in one
direction or the other is flowing both somewhat before and somewhat after each
crank has crossed its in-centre but it is so arranged that the current is greatest
shortly after crossing the centre so that a sufficient spark is obtained at starting
when the speed of the motor is slow.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.

page_text: Improvements in the Igniting Arrangements of Gas and Oil.
Motor Engines.
I, FREDERICK WILLIAM LANCHESTER, of Cobley Hill, near Alvechurch, in the
County of Worcester, 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:-
This invention relates to improvements in the ignition arrangements of gas
and oil motor engines and refers more particularly to igniters in which an
electric spark is employed; this invention has for its object to dispense with the
battery usually emploved and to provide a magneto-electric generator without
adding to the weight of the machine.
Two methods of carrying my invention into effect are illustrated in the
accompanying sheet of drawings in which,
Figures 1 and 2 are respectively a side sectional elevation and a front elevation
of one modification and,
Figures 3 and 4 similar views of a second modification.
In the mode of carrying this invention into effect as illustrated in Figures 1
and 2 of the drawings I arrange a permanent magnet A of circular ring forms
securely attached or embedded in the rim of the flywheel B which is made of
gun metal or other suitable non-magnetic material, the aforesaid circular magnet
may be built up of a number of laminæ or turned in a single piece and is
hardened and tempered in the usual manner, and in this arrangement a segment
at C is cut from the ring A and magnetisation is effected to produce north and
south poles at the two extremities as shown in Figure 2. At suitable points a
stationary soft iron armature D is arranged having its poles E and F in proximity
to the rotating magnet A and a coil G is fitted to the armature to supply the
ignition current to the motor cylinder. A gun metal gag piece is fitted at C to
re-place the cut out segment and keep the wheel in balance.
Figures 3 and 4 illustrate a slight modification of the preceding device viz, the
magnet A is not cut but left intact and consequent poles are arranged as shown
with the armature D crossing the width of the flywheel B. Any number however
of consequent poles may be arranged at suitable equi-distant points with a
corresponding arrangement of armature and coil to supply the ignition current.
The permanent magnet may form, a large proportion of the weight of the
flywheel rim or the flywheel may be built up with a hard steel magnetised rim,
so that a very massive permanent magnet may be employed without any increase
in the total weight of the motor.
Where a number of motor cylinders are employed a corresponding number of
armatures may be arranged or a single armature may be made to do duty and a
number of pole gaps arranged in the magnet.
The positions of the fixed armatures are so arranged that a current in one
direction or the other is flowing both somewhat before and somewhat after each
crank has crossed its in-centre but is preferably so arranged that the current is
greatest shortly after crossing the centre so that a sufficient spark may be obtained
at starting when the speed of the motor is slow.
The ignition device used in conjunction with the herein before described
magneto-electric arrangements is preferably of the internal break type in which
the circuit is mechanically broken with considerable suddenness within the
combustion space at the moment when it is desired to effect the ignition of the

page_text: charge and the position of the armature relatively to the poles of the magnet is
so arranged that at the moment of breakage the current shall be at a maximuli.
By utilising a large proportion of the weight of the flywheel as a permanent
magnet I find that I can obtain a sufficient current for the purposes of ignition
at y speed of the motor and even at starting without employing armatures of
greater weight than is necessary for a coil when a battery is employed, and this
is especially valuable where great lightness is essential and where the weight of
magneto-electric arrangements as heretofore applied would be prohibitive.
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 electrcal igniters for gas or oil engines the provision of a permanent
magnet forming a large proportion of the weight of the flywheel and revolving
in the vicinity of a suitabi wound armature as a means of producing the necessary
current to effect inition substantially as herein before described.
2. The improvements in electrical igniting arrangements substantially as and
for the purpose hereinbefore described with reference to the accompanying
drawings.
MARKS & CLERK,
18, Southampton Buildings, Chancery Lane, London, W.C., and
13, Temple Street, Birmingham, Agents.