Year: 1886

page_text: Date of Application, 9th Oct., 1886.
Complete Left, 20th May, 1887.
Complete Accepted, 21st June, 1887.
I, THOMAS POWNALL FORD junior of 38 Old Jewry in the City of London
Engineer, do hereby declare the nature of this invention to be as follows:-
My Invention relates to improved means of controlling the working of that kind of
hydraulic lift in which the cage is suspended by a chain or rope passing round an
overhead sheave and is actuated and controlled by a double acting piston working in
a vertical cylinder with a column of water above and below it; and the Invention has
for its object to avoid the bissing noise usually caused by the water in passing through
the outlet valve when the piston is descending.
Attempts have heretofore been made to obviate this objection and to a certain extent
successfully by automatically checking the discharge from the cylinder, but this gives
rise to objectionable irregularity of motion of the piston.
The Invention relates to the employment of means of controlling the inlet and
outlet of water to and from the two ends of the cylinder simultaneously and to the
same extent, whereby the hissing noise which usually occurs at the outlet valve is
prevented, and to the employment, in combination with valves operated simultaneously
and equally as above described, of a column of water partially counter acting the
pressure of the water entering through the inlet valve, whereby the hissing noise is
prevented from occurring at that valve.
By this means the defect in question is cured without prejudicing the operation of
the lift.
In carrying the Invention into effect, I provide an equilibrium valve controlling the
admission from the main and connect it with the circulating and outlet valves (which
may either be of the usual piston type or may be slides) by the same spindle or other-
wise, so that they shall be operated simultaneously and will always open the inlet and
outlet to an equal extent, and the water entering through the inlet valve may be
checked by the opposing column of water contained in the circulating pipe, i.e. the
pipe through which the water from the upper end of the cylinder conveyed to the
lower end, to permit of and control the descent of the cage.

page_text: The inlet, circulation, and outlet valves preferably work in the same casing to
which the supply main and the circulation and outlet pipes are connected, the dis-
position of the valves and ports being such that when the supply main is put into
cominunication, through the circulation pipe, with the upper end of the cylinder, the
outlet from the lower end of the cylinder will be open to the exhaust to an extent
corresponding to the supply, and when the admission and exhaust are cut off and
the valves are at the middle of their travel all the ports will be closed and the piston
will be held stationary; and when communication between the two ends of the
cylinder is established the admission and exhaust will remain closed and water will be
permitted to flow from one side of the piston to the other to allow of the motion of
the piston and the descent of the cage under the control of the valve which governs
the circulation of the water.
A bye-pass from the main is provided, in order that the water passing from one
end of the cylinder to the other may be supplemented by the quantity necessary to
compensate for the difference of area at the two sides of the piston due to the
displacement of the piston rod.
In applying the improvements to existing machinery the inlet valve, although com-
bined with the circulation and exhaust valves as before, may be contained in a
separate cylinder, to which a branch pipe leading to the circulation pipe would be
connected, this branch pipe or the circulation pipe containing the column of water
by which the inlet from the main is checked, as previously mentioned, a bye-pass
being provided, as in the former case.
Dated: all
1002
T. P. FORD.
By A. M. & Wm. (lark,
53, Chancery Lane, London,
Patent Agents.

page_text: שבת
Improvements in Hydraulic Lifts.
I THOMAS POWNALL FORD junior, of 38 Old Jewry in the City of London,
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 improved means of controlling the working of that kind of
hydraulic lift in which the cage is suspended by a chain or rope passing round an
overhead sheave and is actuated and controlled by a piston working in a vertical
cylinder with a column of water above and below it; and the Invention has for its
object to avoid the hissing noise usually caused by the water in passing through the
valves, particularly through the outlet valve, when the piston is descending. Attempts
have, heretofore, been made to obviate this hissing noise at the outlet valve, and to a
certain extent, successfully, by automatically checking the discharge from the cylinder,
but this gives rise to objectionable irregularity of motion of the piston.
This Invention relates to means whereby the defect in question is cured without
prejudicing the operation of the lift; and it consists in the employment of means of
controlling the inlet and outlet of water to and from the two ends of the cylinder
simultaneously and to the same extent whereby the hissing noise which usually occurs
at the outlet valve is prevented; and to the employment, in combination with valves
operated simultaneously and equally as above described, of a column of water partially
counteracting the pressure of the water entering through the inlet valve, whereby the
hissing noise is prevented from occurring at that valve. It further relates to the
employment in combination with the inlet valve of a perforated diaphragm and of an
automatic check valve which is caused by a spring to close against the pressure of the
water from the supply and which is only intended to have any appreciable effect when
the cage is being raised empty or with a very light load.
Reference is to be had to the accompanying drawing forming part of this
Specification; wherein I have represented a vertical sectional elevation of the valve
cylinder and valves, and as much of the main cylinder and pipe connections, as is
necessary to explain the Invention. In the drawing, the valves are shewn in the
closed position.
A is part of the main cylinder, and B the valve cylinder connected with the top
and bottom ends of the main cylinder by pipes C and D respectively, these pipes
both connecting with the valve cylinder near the lower part thereof. E is the
inlet pipe from the source of pressure connecting with the valve cylinder near
the upper part, as shewn. F is the inlet valve, G the circulation valve, and H the
outlet valve. In the example shewn, they are of the ordinary piston type (but they
might be slides) and are all connected to the same valve spindle I or otherwise
connected so that all will be operated simultaneously and to the same extent
by means of the same hand gear. Above the inlet valve F is a second piston FI
which serves to equilibrate the pressure, on the upper face of valve F, of
the water from the main E when the inlet valve is closed, as shewn.
The

page_text: circulation valve G performs the same function for the outlet valve H with regard
to the pressure from the lower end of the main cylinder when the outlet is closed.
K is the automatic valve fitted to slide on the valve-rod I. It is closed by a
spring within a seat ¹ carried at the underside of the inlet valve F, a
spring being applied at the other side of the valve K to serve as a cushion
for the valve. There is a space between these two valves F and K in which is
placed a perforated diaphragm carried by the body of the valve F. J is an
inlet aperture, through which the water from the main E passes, part of the water
passing through the perforations of diaphragm whereby the How is checked.
The pressure acting against valve K overcomes the spring and moves the valve K
from its seat when the inlet valve F is raised above the port of main E. The port
of pipe is always between the inlet valve and the circulation valve and by lowering
the valves until the valve G is below the port of pipe D the pipe C is put into
communication with the pipe D through the valve cylinder B for permitting the
circulation of water from the upper to the lower end of the main cylinder in the
ordinary way, when the cage is descending. The disposition of the valves and their
ports is such that when the supply main E is put into communication, through the
circulation pipe C with the upper end of the main cylinder A, the outlet D from the
lower end of the said cylinder will be open to the exhaust to an extent corresponding
to the supply through the valve F. The pressure of the column of water contained
in the pipe C, which is nearly equal in height to the main cylinder, opposes the flow
of water entering through the inlet valve and, together with the friction of the moving
parts of the lift, partially counteracts the pressure from the main, the automatic
auxiliary valve K assisting in the same way when the cage is light, thus preventing
hissing at this valve. When the cage is heavily loaded, the valves can be raised until
valve K is entirely above the port of main E so that the full pressure of the main is
available. When the admission and exhaust are cut-off and the valves are at the
middle of their travel, as represented in the drawing, all the ports will be closed and
the piston in the main cylinder A will be held stationary. When communication
between the two ends of the cylinder A is established through pipes C and D, the
admission and exhaust will remain closed and water will be permitted to flow from one
side of the piston in the main cylinder to the other, to allow of the motion of the
piston and the descent of the cage, under the control of the valve G which governs
the circulation of the water. A small bye-pass pipe L, from the main E, is provided
in order that the water passing from one end of the main cylinder A to the other may
be supplemented by the quantity necessary to compensate for the difference of area at
the two sides of the piston due to the displacement of the piston-rod. This bye-pass
puts the supply main E in permanent communication with pipe C.
Having now particularly described and ascertained the nature of the said Invention,
and in what manner the same is to be performed, I declare that what I claim is ;
In a valve gear for hydraulic lifts; consisting of an equilibrated system of inlet
circulation and exhaust valves connected together the inlet and exhaust valves
being equidistant from their respective ports, as herein described; the combination
with the inlet valve of a perforated diaphragm and a spring actuated auxiliary valve
acting against the pressure from the main, so as to check the inflow through the inlet
valve when the cage is raised with a light load, substantially as specified.
Dh: 10th
1007