An Improvement in Valves for Hydraulic Presses.
Year: 1894

page_text: Date of Application, 18th July, 1894
Complete Specification Left, 11th.Apr., 1895-Accepted, 11th May, 1895
PROVISIONAL SPECIFICATION.
An Improvement in Valves for Hydraulic Presses.
I, CHARLES Downs, Engineer of The Old Foundry, Hull do hereby declare
the nature of this invention to be as follows:-
•
In order to save expenditure of very high pressure water in working hydraulic
presses, water of lower pressure is often employed to move the plunger through
part of its stroke, and then the water of very high pressure is turned on to complete
the stroke.
My invention relates to an arrangement of valves whereby this mode of operating
is effected automatically.
For this purpose, in the passage from the low pressure accumulator I fit, under
the discharge valve, a check valve which is closed down when the discharge valve
is opened, and in the passage from the high pressure accumulator I fit a plunger
terminating in a valve face, which is kept seated by a spring adjusted to the lower
pressure.
These valves operate in the following manner; the discharge valve being closed
and thus leaving the low pressure check valve free, low pressure water passes this
valve into the cylinder moving the plunger as far as the low pressure can carry it.
This pressure then acting on the spring plunger raises it opening the valve with
which it terminates, and thereupon the high pressure water passes into the cylinder
closing the check valve in the low pressure passage. When the pressing operation
is completed the discharge valve is opened, closing the low pressure check valve
and, at the same time, the spring closes the high-pressure valve so preventing
communication from the high pressure supply to the exhaust passage. The
operation is thus completed.
Dated this 18th day of Jul 1904
ABEL & IMRAY,
Agents, for the Applicant.
1, CHARLES DOWNS, Engineer, of The Old Foundry, Hull, 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 :-
In order to save expenditure of very high pressure water or other fluid in
working hydraulic presses, fluid of lower pressure is often employed to move the
plunger through part of its stroke, and then the fluid of very high pressure is
turned on to complete the stroke.
My invention relates to an arrangement of valves whereby this mode of operating
is effected automatically as I shall describe referring to the accompanying drawing
which is a section of a valve box according to my invention.
A is the passage from the low pressure accumulator provided as usual with
regulating valve B; in this passage under the discharge valve D I fit a check

page_text: valve C which is closed down when the discharge valve is opened, by screwing
down D so as to put the exhaust passage E in communication with the pipe F
leading from the press. G is the passage from the high pressure accumulator
provided with regulating valve H. In this passage I fit a plunger P terminating
in a valve face which is kept seated by a spring S adjusted to the lower pressure.
These valves operate in the following manner: the discharge valve D being closed
and thus leaving free the low pressure check valve C, low pressure fluid passes this
valve and flows by the pipe F into the cylinder, moving the plunger thereof as far
as the low pressure can carry it. This pressure then acting on the spring
plunger P raises it, opening the valve with which it terminates, and thereupon the
high pressure fluid flows from G through passage K and pipe F into the cylinder
closing the check valve C in the low pressure passage.
When the pressing operation is completed the discharge valve D is opened,
closing the low pressure check valve C and, at the same time, the spring S
depressing the plunger P closes the high pressure valve so preventing commu-
nication from the high pressure supply G to the exhaust passage E. The operation
is thus completed.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
A valve box with valves and passages for a hydraulic press arranged and
operating substantially as described with reference to the drawings, for the purpose
set forth.
Doted this 11th day of Anil 1905
ABEL & IMRAY,
Agents for the Applicant.