An Improved Hydraulic Engine for Organ Blowing.
Year: 1897

page_text: Date of Application, 29th Dec., 1897
Complete Specification Left, 27th Sept., 1898-Accepted, 12th Nov., 1898
An Improved Hydraulic Engine for Organ Blowing.
ARTHUR ANDERSON WATKINS and JOHN DE LANNOY WATSON, of 16, White Lion
Street, Islington, London, Engineers, do hereby declare the nature of this invention
to be as follows:-
This invention relates to engines of the reciprocating type and has for its object
the simplification and reduction of parts, the minimising of any possibility of the
engine getting on a "dead centre "and the easy accessibility to the slide-valve and
reversing cock or valve of same. The slide-valve which closes and opens inlet and
exhaust ports to cylinder is of the equilibrium type, having two piston-valves connected
by a stein one of which has an area approximately double that of the other. The
larger piston valve end is continued with a stem at the end of which is another piston
(hereafter called the valve driving piston) of the same diameter as the larger piston
valve. The slide-box is bored to fit the piston valves and the valve driving piston at
the parts in which they move. The pressure water is admitted between the two
piston valves and the space on the other side of each of these is open to the exhaust..
On the further side of the valve driving piston water is admitted or exhausted by a
two-way cock or valve.
The pressure water being admitted into the slide-box between the large and small.
piston valves, forces the slide-valve in the direction of the larger piston-valve to the end
of its stroke and allows the water to pass through ports to one side of engine piston
and moves it forward, which as it approaches the end of its stroke, works the usual
tappet action and moves the cock in connection with the valve driving piston chamber
into such a position as to admit pressure water into this chamber, which forces the
slide-valve to the other end of its stroke and at once reverses the engine. The engine
piston on approaching the other end of its stroke reverses the tappet action bringing
the cock into its original position and allows the pressure water in the valve
driving piston chamber to exhaust and the slide valve moves again in the direction
of the larger piston valve, thus completing the cycle and establishing the reciprocating
movement of the engine.

page_text: 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 an improved form of reversing valve for reciprocating
hydraulic engines and we herewith proceed to fully describe same with reference to
the drawings.
Figure 1 represents in section the valve box in which works the slide-valve B with
pistons CDE F. D & E are simply "cut off" pistons of the ordinary equilibrium
cylindrical type. C & F work in small cylinders C being about twice the size of F.
Pressure is always maintained in the space behind piston F it being in connection by
passage ff with the chamber G into which pressure water is admitted. The ports I J
communicate respectively with either end of the engine cylinder. The exhaust
ports M&N lead to the discharge opening at H.
When the valve is in the position represented in the drawing, pressure water is
free to pass to one end of the engine cylinder from G to the port. J and the other end
of the cylinder is free to exhaust through the port I & passage M M to H.
At the end of the valve-box this attached the cock K. Pressure water is brought
to one end of the cock by the passage I and the other end of the cock is
connected to the exhaust outlet by the passage P.
This cock is worked with tappet action or levers by the reciprocal movement
of the engine piston-rod, to the crosshead of which such tappet action or system
of levers are connected, and this cock is reversed (its movement being about a
quarter revolution each stroke) at each end of the stroke of the engine piston.
When the valve is in the position in which it is drawn, water is admitted to the
back of the valve piston C from chamber G through passage L to the cock and
thence through port g and has driven the piston C and slide valve B to the
position shewn, and maintains it in that position owing to the larger area of
piston C overcoming the pressure in the reverse direction exerted by piston F.
Upon the engine arriving at the other end of its stroke the cock is reversed, the small
port is closed and his opened whereby the water in the small cylinder Q is
enabled to escape through port h and passage P & M into the exhaust.
Piston F is then enabled to exert its force and drive the slide valve in the direction
of the arrow till it comes to a stop at the other end of the slide box in so doing
it will connect the port I with the pressure water and the port J with the exhaust
so reversing the engine.
When the engine piston has completed the stroke thus effected it will again
reverse the cock and the slide valve will return to the position in which it is shown
in the drawing thus establishing the reciprocal action of the engine.
Figure 2 shews an alternative manner of effecting the same reciprocal movement
of the slide-valve. The reversing cock K is precisely the same in both designs and
is therefore not shewn in the drawing.
The pistons c & d are in this case both of the same size as one another, the
piston é being as before, of about half the area of c and the 4th piston F (Fig. 1) is
not required. When pressure is admitted into cylinder g the piston is driven to and
maintained in the position shewn, when this pressure is liberated, the pressure in
chamber G will drive the valve in the opposite direction owing to the area of piston d
being greater than that of piston e.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
1. In hydraulic engines the driving of the slide valve by pistons of different area,
the larger piston driving by the admission of pressure into one end of the cylinder
in which it works, and by the exhaustion of the same leaving the smaller piston free
to drive it in the contrary direction.
2. In bydraulic engines the driving of the slide valve by pistons of different area,
the normal position of the slide valve (considered apart from the action of the

page_text: reversing cock or valve) being at the end of its movement, owing to the constant
pressure on a differential area, and the forcing of the slide out of its normal position,
and in the reverse direction by the admittance of pressure to a third piston capable
of doing so.
3. In hydraulic engines the controlling of the movement of the slide valve through
a cock or valve alternately admitting and liberating water pressure to one side of the
piston connected to the slide valve.