Year: 1895

page_text: ARTHUR ANDERSON WATKINS and JOHN DE LAUNOY WATSON, Engineers
of 16 White Lion Street, Islington, London do hereby declare the nature of this
invention to be as follows:-
This invention relates to engines of the reciprocating type.
The slide valve is of the equilibrium type having two pistons separated by a
stem the stem part working in the pressure water space of the valve box, and the
two pistons in cylindrical chambers opposite cach other, one on each side of the
valve box.
One piston of the slide valve is as much larger than the other as will give
sufficient force to drive the valve in the direction of the larger piston.
The valve at the larger piston end is bored up & fitted with a small stationary
piston or plunger which is of such a size that when the pressure is admitted to this
small piston the power shall be sufficient to, and for the purpose of driving the
valve in the opposite direction.
Between the two piston ends of the valve and on the stem of the valve itself is
fitted a small jockey or slide valve with ports in it and on the surface on which it
works arranged in the ordinary manuer so that the pressure may be admitted to
the aforesaid small piston, or the water from it exhausted.
By moving the small jockey slide therefore, which is effected by mechanical
means from the outside of the valve box,-a reciprocatory movement is given to
the main slide valve.
One of the pistons of the main valve passes over a port leading into the back
end of the engine cylinder, its traverse being such that at one end of its stroke it
frees the port and allows admission of pressure water to this end of the cylinder ;
and at the reverse stroke the valve piston clears this port again and leaves it in
communication with the exhaust.
The front and piston rod side of the engine piston is always in free communication
with the pressure water so that when the back end of the cylinder is free to exhaust
the force of the water pressing on the piston in front, drives it backwards. When
however the valve has reversed and caused the pressure water to enter the back
end of the cylinder the piston is driven forward owing to the area of the piston on
that side being as much greater than the front side as the sectional area of the
piston rod.
An arm from the piston rod actuates the gear which reverses the jockey slide
and in this manner the engine continues its reciprocatory movement.
Dated this Twenty-seventh day of February 1895.
ARTHUR A. WATKINS.
J. DE L. WATSON.

page_text: We ARTHUR ANDERSON WATKINS Engineer and JOHN DE LAUNOY WATSON
Engineer of 16 White Lion Street Islington London 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 engines of the reciprocating type the slide valve
being of the equilibrium type having two pistous separated by a stem, the stem
part working in the pressure water space of the valve box and the two pistons
in cylindrical chambers opposite each other one on each side of the valve box.
One piston of the slide valve is as much larger than the other as will give
sufficient force to drive the valve in the direction of the larger piston.
The valve at this larger end is bored up & fitted with a small stationary piston
or plunger which is of such a size that when the pressure is admitted to the
small piston the power shall be sufficient to & for the purpose of driving the
valve in the opposite direction.
Between the two piston ends of the valve and on the stem of the valve itself is
fitted a small jockey or slide with ports in it and on the surface on which it works
arranged in the ordinary manner so that pressure may be admitted to the aforesaid
small piston, or the water from it exhausted. Therefore by moving the small
jockey slide (which is effected by mechanical means from the outside of the valve
box) a reciprocatory movement is given to the main slide valve.
One of the pistons of the main valve passes over a port leading into the back
end of the engine cylinder, its traverse being such that at one end of its stroke it
frees the port and allows admission of pressure water to this end of the cylinder
and at the reverse stroke the valve piston clears this port again and leaves it in
communication with the exhaust.
The front and piston rod side of the engine piston is always in free communi-
cation with the pressure water so that when the back end of the cylinder is free to
exhaust, the force of the water pressing on the piston on the front side drives it
backwards.
When however the valve has reversed and caused the pressure water to enter
the back end of the cylinder the piston is driven forward owing to the area of
the piston on that side being as much greater than the front side as the sectional
area of the piston rod; or working as a ram by the pressure on the sectional area
of the piston rod alone.
An arm from the piston rod end or crosshead actuates the gear which reverses
the jockey slide & in this manner the engine continues its reciprocatory movement.
We will now more particularly describe our invention with reference to the
drawings.
A is the cylinder with its piston B. C is the valve box or chamber into which
the pressure water is admitted. Dis the slide valve with its two pistons E & F.
The front of the cylinder is always in communication with pressure water by the
passage G and the other end of the cylinder is sometimes free to exhaust & some-
times in communication with the valve chamber when pressure water is admitted.
This is the case in the position in which it is represented in the drawing, & the
admission of water will drive the piston forward. When it arrives at the end of
its stroke the rod H attached to the crosshead pulls over the arm I to which it is
connected, and this causes the forked lever J to move the jockey slide K forward;
in doing so water is admitted through the ports L & M to the small piston or
ram N and the slide D is driven forward. The back end of the cylinder A is then
open to the exhaust and pressure being on the other side of the piston B, the
piston is driven backwards which arriving at the back end of its stroke reverses

page_text: the jockey slide K by means aforesaid of the rod H & levers I & J & the water
from the small piston N is exhausted through the passages M. O. & P and owing
to the piston E being larger than the piston F the slide D is reversed and brought
again to the position shewn in the drawing.
Having now fully described our invention we claim
The slide valve D with its differential pistons E & F in connection with the
jockey slide K and piston ram N causing the reversion of the piston rod or ram R
of the main cylinder substantially as shewn and herein before described and for the
application to high-pressure hydraulic engines.
Dated this 26th day of November 1895.
ARTHUR ANDERSON WATKINS.
JOHN DE LAUNOY WATSON.