An Improved Four Stroke Cycle Motor for Bicycles and the like
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
An Improved Four Stroke Cycle Motor for Bicycles and the like.
(A communication by BORIS LOUTZKY, of Nuremberg, in the Empire of Germany.)
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool,,and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Birmingham, in the County of
Warwick, and 322, High Holborn, in the County of Middlesex, Civil Engineer,
do hereby declare the nature of this invention to be as follows:-
Cycle motors must be made as light as possible in weight, as compact as possible
in construction, and as simple as possible in all parts. Further, the discharged
gases must cause no objectionable or troublesome noise.
The whole driving mechanism of the motor inclusive of the valve controlling
mechanism is, according to the present invention, contained in a closed casing on
which the cylinder is mounted.
In these small cycle motors, which mostly develop less than one horse power,
it has moreover been found by experiments made with the cylinder that, for the.
purpose of a sure ignition, a straight narrow igniting passage must be employed,
which should be filled with as far as possible a pure mixture. For this object in
the present machine, the discharge valve is arranged in the narrow igniting passage
in front of the air suction valve, so that during the compression stroke of the
machine only a pure mixture exists at the outermost end of the igniting passage
over the valve. The valve rods also lie in one plane with the vertical axis.
In order preferably to regulate both these valves arranged in series or one behind
the other, the controlling levers belonging thereto must also lie in a similar vertical
plane and be operated by a common cam. In order to attain this object the controll-
ing lever of the discharge valve is arranged vertically over the controlling lever
of the air valve in the same plane. The cam-engaging points of both levers are
displaced in such a way on a centric angle of 90° that the common cam serves for
controlling both the suction valve and also the discharge valve. In the case of
bicycle motors which preferably are provided with a means for suppressing the
noise of the exhaust, it has been found that a back pressure is exerted on the exhaust
or discharge gases by said device for suppressing the noise. For overcoming this
back pressure, the discharge valve by the present invention is opened a little
shortly before the completion of the expansion period so that a portion of the
consumed gases can escape under pressure. With the object of obtaining this
quickening of the movement of the discharge valve, the valve controlling cam is
provided with a step which operates the lever of the discharge valve, whilst the
shorter projection of the operating lever of the air valve is not operated by this
step. Owing to the fact that both the valves, their rods, and their controlling levers
and also the common cam lie in the one plane, it is possible to have on the one
hand an arrangement of a suitably narrow igniting passage fed with pure mixture
at its end, and on the other hand an extremely compact construction of the cycle
motor.
:

page_text: With the object of thus saving space the crank shaft which is double mounted
in the casing is only provided at one side with a flywheel, while on the other side
a cogwheel is keyed, which engages with a cogwheel on the valve operating shaft
so that the total driving mechanism of the above mentioned motor is contained
in the closed narrow casing.
L 11 •
An Improved Four Stroke Cycle Motor for Bicycles and the like.
(A communication by BORIS LOUTZKY, of Nuremberg, in the Empire of Germany.)
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Birmingham, in the County of
Warwick, and 322, High Holborn, in the County of Middlesex, Civil 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:-
Cycle motors must be made as light as possible in weight, as compact as possible
in construction, and as simple as possible in all parts. Further, the discharged
gases must cause no objectionable or troublesome noise.
This invention has for its object an improved four stroke cycle motor for bicycles
and the like which fulfils all the above requirements and is shown in the
accompanying drawings,
Figure 1 being a cross section, and
Figure 2 a longitudinal section, whilst
Figures 3 and 4 are details.
The whole driving mechanism of the motor inclusive of the valve controlling
mechanism is, according to the present invention, contained in a closed casing a on
which the cylinder bis mounted.
In these small cycle motors, which mostly develop less than one horse power,
it has moreover been found by experiments made with the cylinder that, for the
purpose of a sure ignition, a straight narrow igniting passage must be employed,
which should be filled with as far as possible a pure mixture. For this object in
the present machine, the discharge valve d is arranged in the narrow igniting
passage c in front of the air suction valve e, so that during the compression stroke of
the machine only a pure mixture exists at the outermost end of the igniting
passage over the valve e
The valve rods and e¹ respectively also lie in one
plane with the vertical axis of the cylinder b.
In order to regulate both these valves d and e, preferably arranged in series or
one behind the other, the controlling levers f and g belonging thereto must also
lic in a similar vertical plane and be operated by a common cam h. In order to
attain this object the controlling lever f of the discharge valve is arranged
vertically over the controlling lever g of the air valve in the same plane. The
cam engaging points of both levers f and g are displaced in such a way on
centric angle of 90° that the common cam h serves for controlling both the suction
valve e and also the discharge valve d. In the case of bicycle motors which
preferably are provided with a means for suppressing the noise of the exhaust, it
has been found that a back pressure is exerted on the exhaust or discharge gases
by said device for suppressing the noise. For overcoming this back pressure, the
a

page_text: discharge valve d by the present invention is opened a little shortly before the
completion of the expansion period, so that a portion of the consumed gases can
escape under pressure. With the object of obtaining this quickening of the move-
ment of the discharge valve d the valve controlling cam h, as shown in Figure 4,
is provided with a step or bevelled part n which operates the lever f of the
discharge valve, whilst the shorter projection of the operating lever of the air
valve is not operated by this step n. Owing to the fact that both the valves d
and e, their rods d' and e¹ and their controlling levers f and 9 and also the common
cam lie in the one plane, it is possible to have on the one hand an arrangement
of a suitably narrow igniting passage e fed with pure mixture at its end, and on
the other hand an extremely compact construction of the cycle motor.
With the object of thus saving space the crank shaft i which is double mounted
in the casing a is only provided at one side with a flywheel k, while on the other
side a cogwheel is keyed, which engages with a cogwheel on the valve operating
shaft m so that the total driving mechanism of the above mentioned motor is
contained in the closed narrow casing a.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is:
-
The improvement in explosion engines, characterized by two levers (f and y)
being arranged one above the other to be operated from a common controlling
cam (h), the cam-engaging points of said levers being displaced on a centric angle
of 900 and the cam (4), with the object of accelerating the movement of the dis-
charge valve (d), being provided with a bevelled part or step (n) adapted to operate
only the lever (f) of the discharge valve, substantially as hereinbefore described.
Dated this 26th day of January 1898.
WM. P. THOMPSON & Co., Agents.