Improvements in and relating to Electrical Contact Devices for Explosion Engines Fired by Electricity.
Year: 1899

page_text: Date of Application, 18th May, 1899
Complete Specification Left, 19th Mar., 1900-Accepted, 21st Apr., 1900
PROVISIONAL SPECIFICATION.
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114
Improvements in and relating to Electrical Contact Devices for
Explosion Engines Fired by Electricity.
الموز
i
1, JAMES GEORGE ACCLES, of Holford House, Perry Barr, Birmingham, in the
County of Warwick, Engineer, do hereby declare the nature of this invention
to be as follows:-
S...
This invention relates to contact devices for use in electrically igniting the
explosive charges..in oil or gas engines, and for varing what is known in con-
nection with explosion engines as "timing," that is to say, the passing of a
high tension spark between two terminals inside the cylinder of the engine at
varying times during the cycle of operations, at the will of the driver.
According to my invention I employ a roller, drum or cylinder 'made of
vulcanite, vulcanised fibre, or any other suitable insulating material, having on
its periphery a piece of metal which is not parallel to the axis of the drum but
crosses it at an angle, forming thereon a portion of a rapid helix. This drum
may be mounted on the axis of the cam wheel of the engine, actuating the
exhaust valve,, or in any other convenient position where it can be caused to
revolve by the engine. Acting in conjunction with said drum is a bell crank,
one end of which carries a contact piece which as the drum revolves' bears alter-
nately on the insulating portion and on the metal helix. The other end of the
bell crank is connected by suitable mechanism to a handle within the driver's
reach so that said bell crank can be moved at the will of the driver. When
this bell crank is shifted about its pivot by means of the said.handle, the contact
piece can be caused to assume such a position relatively to the helix that the
firing of the explosive charge in the working cylinder of the engine will take
place earlier or later, according to the direction in which said contact piece is
moved.
The contact piece may, in some cases be fixed, and the drum itself be moved
longitudinally on its axis by suitable mechanism, a similar result with regard
to "timing" being thereby obtained.
Instead of arranging the said contact piece at the end of a bell crank, I may
arrange it at the end of an arm adapted to slide parallel with the axis of the
drum.
The said drum is also provided with a peripheral metallic portion preferably
at, one of its ends, which remains constantly in electrical contact with another
contact piece in the same electrical circuit with the other contact piece. The
helical and peripheral metallic parts of said drum being in electrical connection,
each time the contact piece slides over the helical metallic part the electric
circuit is closed and a spark caused to pass between the sparking treminals.
I adopt any suitable and known method of wiring to connect the improved
contact breaker to the induction coil and batteries and sparking terminals.
HASELTINE, LAKE & Co.,
:
45, Southampton Buildings, London, W.C., Agents for the Applicant...

page_text: Improvements in and relating to Electrical Contact Devices for
Explosion Engines Fired by Electricity.
I, JAMES GEORGE ACCLES, of Holford House, Perry Barr, Birmingham, in the
County of Warwick, 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 contact devices for electrically igniting the explosive
charges in oil or gas engines, and for varying the operation known in con-
nection with explosion engines as "timing," that is to say, the passing of a
high tension spark between two terminals inside the cylinder of the engine at
varying times during the cycle of operations, at the will of the driver.
According to my invention, I employ a cylinder or drum of insulating
material, having on its periphery a metallic portion or strip which lies at an
angle to the longitudinal axis of the cylinder or drum forming thereon a portion
of a rapid helix. This drum may be mounted on the axis of the cam wheel
employed for actuating the exhaust valve of the engine, or may be arranged in
any other convenient position where it can be caused to revolve by the engine.
Acting in conjunction with said drum is a bell crank or other arm, one end of
which carries a contact piece which as the drum revolves bears alternately on
the insulating portion and on the metallic strip. The other end of the arm is
connected by suitable mechanism to a handle within the driver's reach so that
said arm can be moved at the will of the driver. By moving this aim, the
contact piece can be caused to assume such a position relatively to the metallic
strip that the electric circuit will be opened and closed at an earlier or a later
period in the revolution of said drum according to the direction in which said
contact piece is moved, thus causing the firing of the explosive charge in the
working cylinder to take place at a correspondingly earlier or later period.
In order that my said invention may be clearly understood and readily carried
into effect I will proceed to describe the same more fully with reference to the
accompanying drawings, in which ;-
Figure 1 is a sectional side elevation of one one form of my improved device.
Figure 2 is a plan of the same.
Figure 3 is a sectional side elevation and Figure 4 a sectional plan of a
modined form of the said device.
Figure 5 is a side elevation and
Figure a plan of another modified form of the device.
1
gures 7 and 8 are similar views of a further modified form of the device.
In all these figures like letters of reference indicate similar parts.
A is the rotary cylinder or drum of insulating material, B is the metallic
helical strip on the periphery thereof and C is the arm carrying the contact
piece c.
In the arrangement illustrated by Figures 1 and 2 the drum A is intended to
be keyed to any suitable rotary part of the engine such as the cam-shaft D. The
said drum is provided with an annular metallic portion a which forms part of
the said helical strip B and which during the revolution of the drum remains
in continuous electrical connection with a brush or similar contact piece. This
brush is not shown in the drawings but is of any well known construction. The
said brush is in circuit with the sparking terminals of the working cylinder,
with a galvanic battery or other source of electricity, and with the arm C, the
latter being provided with a binding screw c¹ for enabling the conducting wires

page_text: to be connected thereto The arm C is fixed to a crank-handle (of which only
a portion is shewn in the drawing) in such a manner that by moving the handle,
the contact piece a can be caused to move longitudinally in either direction on
the surface of the drum, so that its time of making contact with the helical
strip B takes place earlier or later according to the direction in which the arm
is shifted and consequently the sparking in the working cylinder occurs, as
already stated, at an earlier or later part of the stroke of the piston.
In order to keep the arm C in effectual contact with the drum, it is made in
the form of a resilient blade and caused to press against said drum with the
This
desired force by adjusting a set screw carried by an arm or bracket t.
arm or bracket participates in the oscillatory movement of the arm C by being
connected therewith by studs c.
The
In Figures 3 and 4 the drum A instead of being composed of insulating
material is made wholly of metal and in one piece with the projecting helical
strip B. The contact piece c is carried by a resilient blade c* supported upon
the arm C which is keyed to the spindle C of the crank-handle ². The resilient
blade e tends to keep the contact piece c pressed against the strip B.
resiliency of this blade is such that although it acts to keep the said piece c in
good electrical contact with the projecting helical strip B as the latter passes
in front of it, the said piece will not move inwardly to a sufficient extent to
come into contact with the cylindrical portion of the drum. The breaking of
the circuit in this instance therefore takes place by reason of the contact piece
being entirely out of contact with the drum. This device is shewn as being
enclosed in a casing E which also forms a bearing for the said spindle C.
The aforesaid contact piece and its arm C may in some cases be fixed and the
drum A be moved longitudinally on its shaft. Such an arrangement is illus-
trated in Figures 5 and 6. The portion of the shaft carrying the drum is rect-
angular in cross section or is grooved to receive a key or feather on the drum
and the said drum is provided with a collar A¹ for enabling a pivoted fork-piece
to engage therewith for shifting the drum on the shaft, in an analogous manner
to the shifting of a clutch.
Or as represented in Figures 7 and 8 the arm C instead of oscillating as in
Figures 1 to 4 can be arranged to slide parallel with the axis of the drum A, by
mounting said arm on a rectangular bar C2 and sliding it to and fro thereon by
a suitable lever.
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. An electrical contact device comprising a rotary drum bearing a helical
or similar strip of metal which acts in conjunction with a contact arm whose
point of contact can be varied in a direction lengthwise of the drum for the
purpose specified.
2. An electrical contact device having its parts, constructed arranged and
operating substantially as described with reference to any of the examples illus-
trated in the accompanying drawings for the purpose specified.
Dated this 19th day of March 1900.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.