Improved Working Valve for Controlling Hydraulic Presses, Cranes, and the like.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improved Working Valve for Controlling Hydraulic Presses, Cranes,
and the like.
I, THOMAS ROLAND WOLLASTON, of Lyndale, Grange Road, Bowdon, in the
County of Chester, Mechanical Engineer, do hereby declare the nature of this
invention to be as follows:-
:-
My invention relates to hydraulic valve gear in which there are separate
inlet and outlet valves, both contained in one box, and both controlled by an
action in such manner that only one such valve can be opened at once, and
further so constructed that when either valve is open it shall be in equilibrium,
but when closed there shall be a certain excess of pressure tending to keep it
closed. In order to assist the valve to close, I, in some cases, use a weight or
a light spring of sufficient strength only to overcome the friction of the spindle.
In constructing hydraulic valves in accordance with my invention, I prefer to
use a valve box body of plain rectangular shape, and having only three con-
nections, one for the inlet of water under pressure, one for the outlet, and one
for connection to the hydraulic ram cylinder.
For controlling and operating the valves, I mount a cam shaft over the valve
box, such shaft passing through slotted heads formed on the upper outer ends
of the valve spindles, and within which heads the cams are situated. Rotation of
the desired extent and direction is given to the shaft by means of a chain or cord
passing over a suitable pulley mounted thereon. The cams are so constructed
that only one of the valves can be open at any one time, or I may use a hand
wheel or lever for operating the valves in a similar manner.
The upper part of the spindle passes through a packing or cup leather in the
usual way, and the face of the valve is formed preferably, by a reduction in
the size of the spindle without any enlargement above it. Below the valve there
is a considerable reduction in diameter, and the lower end has a screw thread
formed upon it. On to this thread-a tail spindle is firmly screwed, having a
diameter just equal to the upper portion of the upper spindle. This tail spindle
passes through a suitable packing or cup leather and projects below the valve
box. To suit this construction and to accomplish the purpose of my invention,
the valve box which is bored to suit the spindle above the seating, is reduced to
form the seating and enlarged again below the seating to the same diameter as
above. There is thus a chamber formed below the seating, and into this
chamber the inlet is led. The outlet is led from a chamber formed above the
seating either by a slight reduction of the spindle diameter for the purpose, or
by an enlargement of the bore of the box.
Thus when the valve is open, the areas of the upper spindle exposed to the
pressure, and those of the tail spindle similarly exposed being equal, the whole
spindle is in equilibrium.
When the valve is closed the pressure of the inlet only obtains access to so
much of the area of the upper spindle as is below the seating, while it still

page_text: operates upon the full exposed area of the tail spindle, and thus tends to force
the spindle downwards, and the valve to its seat with a force due to the excess
of the latter area, and which can be determined at will by the construction of
the valve and spindles.
Both inlet and outlet valves are similarly constructed, the port of discharge
from the ram cylinder being, in the case of the latter, led into the space below
the seating, as above described.
The operation of the cams is to lift the valve spindle so as to open the valve,
but I prefer to allow the spindle to fall by its own, or added weight of sufficient
amount only to overcome the packing and other frictions, or
may mount a
I am aware that the spindles of hydraulic valves have previously been extended
through packing below the valve, but the construction and the operation of the
pressures are new, in the case of my invention, to the best of my knowledge and
belief. I am also aware that springs have been applied to the lower end of a
projecting spindle, but their functions and operation have been different from
light spring upon the projecting tail spindle for the same purpose.
mine.
The main object of my invention is to secure great ease of movement' of the
valve spindles and to combine the operating cam or other gear with valves con-
structed to accomplish this purpose in the manner herein before described, while
also securing perfect closing of the valve by downward excess of pressure while
closed, although when open the valve is in equilibrium.
Dated this Seventh day of Auril 1898
EDGAR CONISTON MILLS,
Agent to the Applicant.
Improved Working Valve for Controlling Hydraulic Presses, Cranes,
and the like.
I, THOMAS, ROLAND WOLLASTON, of Lyndale, Grange Road, Bowdon, in the
County of Chester, Mechanical 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:-
My invention relates to hydraulic valve gear, in which there are separate
inlet and outlet valves, both contained in one box, and both controlled by an
action in such manner that only one such valve can be opened at once, and
further so constructed that when either valve is open it shall be in equilibrium,
but when closed there shall be a certain excess of pressure tending to keep it
closed. In order to assist the valve to close, I use a weight or a light spring
of sufficient strength only to overcome the friction of the spindle.
In constructing hydraulic valves in accordance with my invention the valve
bodies are advantageously made of plain rectangular shape, and have only three
connections, one for the inlet of water under pressure, one for the outlet, and
one for connection to the hydraulic ram cylinder.
For controlling and operating the valves I inount a cam shaft over the valve
box, such shaft passing through slotted heads formed on the upper outer ends
of the valve spindles, and within which heads the cams are situated. Rotation of
the desired extent and direction is given to the shaft by ineans of a chain or cord
pulley, handwheel, or lever mounted thereon. The cams are so constructed that
only one of the valves can be open at any one time.
The upper part of the spindle passes through a packing in the usual way, and

page_text: the face of the valve is formed; preferably, by a reduction. in. the size of the
spindle without any enlargement above it. Below the valve there is a consider-
able reduction in diameter, and the lower end has a screw thread formed upon
it. On to this thread a tail spindle is firmly screwed, liaving a diameter just.
equal to the upper portion of the upper spindle. This tail spindle passes through.
a suitable packing and projects below the valve box. To suit this construction
and to accomplish the purpose of my invention the valve box, which is enlarged
to clear the spindle above the seating, is reduced to form the seating and enlarged
again below the seating to the same diameter as above. The inlet leads into
the enlargement below the seating, and the outlet leads from the enlargement
above the seating.
Thus when the valve is open, the areas of the upper spindle exposed to the.
pressure, and those of the tail spindle similarly exposed being equal, the whole
spindle is in equilibrium.
When the valve is closed the pressure of the inlet obtains access only to so
much of the area of the upper spindle as is below the seating, while it still.
operates upon the full exposed area of the tail spindle, and thus tends to force
the spindle downwards, and the valve to its seat, with a force due to the excess
of the latter area, and which can be determined at will by the construction of
the valve and spindles.
Both inlet and outlet valves are similarly constructed, the port of discharge
from the ram cylinder being, in the case of the latter, led into the space below
the seating, as above described.
The operation of the cams is to lift the valve spindle, so as to open the valve,
but I allow the spindle to fall independently of action of the cams but assisted
by a weight or light spring upon the projecting tail spindle.
I am aware that the spindles of hydraulic valves have previously been extended
through packings below the valve, but the construction, and the operation of the
pressures are new, in the case of my invention, to the best of my knowledge and
belief. I am also aware that springs have been applied to the lower end of a
projecting spindle, but their functions and operation have been different from
mine.
The main object of my invention is to secure great ease of movement of the
valve spindles and to combine the operating cams or other gear with valves con-
structed to accomplish this purpose in the manner hereinbefore described, while
also securing perfect tightness of each valve by downward excess of pressure
when closed, although when open each valve is in equilibrium.
Referring to the accompanying drawing upon which Fig. 1 represents a cross
section on line XX, Fig. 2 represents a front view, and Fig. 3 an end view of
a valve constructed in accordance with this invention, the letters on the different
figures referring always to the same parts.
A represents the valve box or body.
B & C are respectively the inlet and outlet valve spindles.
e is the reduced lower end of the valve spindle.
D is the tail spindle equal in diameter to C.
E and e are respectively enlargements in the valve box above and below the
valve seating.
F and are respectively packings for the valve and tail spindles here shewn
in the form of hydraulic leathers.
G is the water inlet to the valve for water under pressure.
H is the opening from and to the valve to and from the ram cylinder whose
action the valve controls.
I is the outlet.
J is the valve seating.
KK are the slotted heads of the valve spindle.
L is the cam shaft working in bearings M M.
N is the controlling wheel here shewn as prepared for a cord for operating.

page_text: 00 are springs arranged to bring the valves down on their seats when
released by the cams.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:
(1) In hydraulic valves a valve spindle and seating balanced when open by
means of a tail piece of effective area equal to that of the spindle but of which
the effective area is reduced when closed, thus destroying the equilibrium at
that time and producing an excess of pressure tending to keep the valve closed,
substantially as and for the purposes described and as illustrated in the
accompanying drawing.
(2) In hydraulic valves the combination of two independent valves, constructed
so as to be in equilibrium when open and having a tendency to keep closed
when closed, within one valve box, one valve controlling the inlet to the ram
cylinder and the other the outlet therefrom, substantially as and for the
purposes described and as illustrated in the accompanying drawing.
(3) The cams and cam shaft in combination with the assisting springs or
weights for operating hydraulic valves constructed so as to be in equilibrium
when open and having a tendency to keep closed when closed such springs or
weights being of sufficient power only to overcome the friction of the packings
substantially as and for the purposes described and as illustrated in the
accompanying drawing.
Dated this 7th day of January 1800