Year: 1886

page_text: JOHN FAIRLAMB PAXTON, Engineer 52 Bensham Road Gateshead-on-Tyne, and
GAVIN RALSTON Engineer 48 Tamworth Road Newcastle-on-Tyne do hereby declare
the nature of this invention to be as follows:-
A cylinder A which has a Piston B moved by means of Steam or other fluids under
pressure.
The Piston Rod C, is attached to the Lever D, by means of a connecting rod or;
sliding block E.
The other end of the Lever D is connected in like manner to the rod F of the large
valve by the sliding block K..
The slide valve of the Cylinder A is actuated by means of the ordinary Eccentrics
worked from the Crank shaft or other shaft having a motion uniform with the Crank
shaft.

page_text: JOHN FAIRLAMB PAXTON Engineer 52 Bensham Road Gateshead on Tyne, and
GAVIN RALSTON Engineer 48 Tamworth Road Newcastle on Tyne 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
See Drawing left with provisional specification.
A cylinder A which has a piston B moved by steam or other fluids under pressure.
The piston rod C is attached to the lever D by means of a connecting rod or sliding
block E.
The other end of the lever D is connected in like manner to the rod F of the large
valve by the sliding block K.
The slide valve of the small cylinder A is actuated by means of the double eccentrics
and link motion of the usual form worked from the crank shaft or other shaft having
a motion uniform with the crank shaft.
The admission of steam to the small cylinder A is depending upon the motion of the
crank shaft. The slide valve of which can be set so as to admit or exhaust the steam
at any part of the stroke.
The large valve can thus be caused to move through the intervention of the lever D
as if it were connected direct to the crank shaft with the ordinary eccentrics.
The small piston B is effectually cushioned and brought to rest by the steam that is
left in the cylinder A after the piston B has passed the first port being compressed
by the steam pressure on the opposite side of the piston B. The speed of the small
piston B and likewise the large valve can be regulated by means of an Oil cylinder
attached to the piston rod C or the slide rod F of the large valve.
Having now particularly described and ascertained the nature of our said Invention,
and in what manner the same is to be performed we declare that what we claim is :
1. An improved method of working the slide valves of Engines by means of an
intermediate pressure cylinder A and lever D so as to reduce the amount of power
taken from the crank shaft which will give greater efficiency to the engine.
2. Giving the large valve a quick opening and quick exhaust which prevents the
steam being wire drawn or regulating the speed of opening of the large valve by
causing the piston B in the small cylinder A to travel quick or slow, which is obtained
by setting the slide valve of the small cylinder A so as to admit the steam as required
also by attaching an oil cylinder to the piston rod C or slide rod F.,
3. A variable travel of the large valve while the travel of the piston B in the small
Cylinder A remains constant which is obtained by moving the sliding block K nearer
to the fulcrum of the lever D the travel of the large valve is reduced and by moving
the sliding block further from the fulcrum of the lever D the travel is increased.
Dated this 2nd day of May 1887.