An Improved Automatic Regulating or Controlling Device for Pumps and Air Compressors.
Year: 1899

page_text: Date of Application, 27th June, 1899-Accepted, 30th Sept., 1899
COMPLETE SPECIFICATION.
An Improved Automatic Regulating or Controlling Device for Pumps
and Air Compressors.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Birmingham, in the County of
Warwick, and 322. High Holborn, in the County of Middlesex, Civil Engineer,
do hereby declare the nature of this invention (which has been communicated to
me by The Foster Engineering Company, 21 and 23, Prospect Street, Newark,
in the State of New Jersey, United States of America), 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 automatic fluid pressure actuated belt, lever, or
electric switch shifter, for starting and stopping a pump or motor and for other
purposes such, for instance, as controlling the operation of a pump for supplying
fluid to a tank or reservoir in which it may be desired to maintain a standard
pressure.
The invention consists in the combination with a cylinder adapted to receive
fluid pressure from a tank or reservoir, and having a differential piston to
which is attached a connecting rod for actuating a valve, or a belt shifter, or a
lever or switch, of an automatic fluid pressure controlled valve of novel con-
struction to connect with said cylinder and tank, and having a waste passage;
and the invention further consists in the feature of construction and combination
of the parts comprised in said valve, as hereinafter described and claimed.
In the annexed drawing illustrating the invention, Fig. 1 is a longitudinal
section of my improved fluid pressure actuated mechanism for operating a belt
shifter, lever or switch. Fig. 2 is an end elevation of a stuffing box and bracket.
The cylinder 1 is connected at one end to a head or bracket 2, which is provided
with a stuffing box 3, on its outer side. On the periphery of the bracket-head is
a boss 4, through which is formed a threaded opening 5 for attachment of a pipe
to connect with a fluid pressure tank or reservoir. This opening 5 communicates
with the cylinder, 1, through a port or opening, 6, for admitting fluid pressure
from the tank or reservoir to that side of the piston head 7 which presents the
least area or surface by reason of the piston rod 8 being on that side and having a
comparatively large diameter. The piston head is provided with packing rings 9
of some soft yielding material, preferably leather, and may be secured to the
piston rod by means of a nut 10, or otherwise. The piston rod passes out through
the stuffing box 3 and at its end is suitably jointed with a connecting rod 11
that, in turn, connects with the belt shifter, or the lever or switch or valve to be
actuated by the movements of the piston.
Un the other end of the cylinder 1 is a cap 12 provided with a opening into
which is tapped a nipple or small pipe 13 which connects with a port 14 of a
three-way automatic fluid pressure controlled valve 15, which communicates with
the fluid pressure tank or reservoir, as hereinafter explained.

page_text: The casing of the valve 15 comprises a cylindrical body-portion having at one
end a circular enlargement 16 screw threaded for engagement of a cover-part 17,
that tightly clamps into place a flexible diaphragm 18 which divides the valve
casing into two chambers. In the chamber 19 on one side of this diaphragm is
a spring 20, the thrust of which is exerted at one end against a plate or block 21
resting against the diaphragm. The other end of the spring 20 bears against a
screw cap 22 that can be adjusted to increase or decrease the compression of said
spring and thus regulate its pressure to correspond with any standard of pressure
required in the fluid pressure tank or reservoir. The chamber 23 on the other
side of the diaphragm 18 communicates through a port 24 with an opening 25
provided in the body-portion of the valve casing for attachment of a suitable pipe
to connect with the fluid pressure reservoir or tank.
In the body portion of the valve casing there is a central longitudinal bore
of reduced diameter for part of its length, next to the diaphragm chamber 23,
and of enlarged diameter at the outer end of said valve casing. The reduced
portion of said bore forms a valve chamber 26 having a valve seat at each end.
This valve chamber 26 receives two valves 27 and 28, the stems of which abut
in such manner that when one valve is closed or seated, the other valve will be
open. The valve stems are tubular and fit the valve chamber, 26, except where
they are circumferentially grooved on the exterior. Each valve stem is provided
with radial holes 29, 30, communicating with its hollow or tubular interior next
to the valve head, and other radial holes 31 are provided at the abutting ends
of the valve stems opposite the port 14 that communicates with the pipe 13 and
connected cylinder.
The valve 27 is normally seated by the pressure of the spring 20 against the
diaphragm 18, and the closing of this valve 27 forces the valve 28 open against
the pressure of a spring 32 that is confined in a chamber 33 formed by the
enlarged portion of the bore in the body of the valve casing. The compression of
the spring 32 is adjusted by means of a centrally bored screw plug 34 that is
screw-threaded or otherwise adapted for attachment of a pipe through which the
exhaust from the cylinder 1 is to escape.
For use in operating a belt shifter the described mechanism is firmly secured,
by means of the bracket 2,. onto the counter shaft frame or other suitable support,
in such manner that the connecting rod 11 may readily be connected to the
sliding bar that carries the belt shifted fingers. Or, in the case of an electrically
driven pump; the bracket 2 may be bolted to the switch board or other suitable
support in such position as will admit of connecting the rod 11 to the switch
lever, or the differential piston. may be connected in any convenient manner
with a valve for controlling the operation of a pump or engine. The opening, 5
which leads into. the cylinder 1, and the opening 25 of the automatic valve 15,
are each to be connected by suitable piping to a pressure tank, or reservoir into
which fluid is to be forced by a pump.
If it is desired to carry, say, 70 pounds pressure in the tank, the threaded
cap 22 will be adjusted to give sufficient compression on the spring 20 to resist or
balance 70 pounds pressure per square inch on the other side of the diaphragm 18,
thus holding down said diaphragm in such position that the valve 27 will thereby
be held to. its seat and this, in turn,, holds the valve 28 open or away from its
seat. Of course, whatever fluid pressure there may be in the tank or reservoir
will also at all times be in that part of the cylinder 1 between its port 6 and the
piston head 7, and also on the underside of the diaphragm 18 through the
opening 25 of the valve casing. When the pressure in the tank is no more than
sufficient to balance the compression of the spring 20, as adjusted by the cap 22,
the piston 7 will occupy, as. shown, such a position as will cause the belt shifter,
or the switch, to permit operation of the pump for maintaining the required.
fluid pressure in the tank. Now as soon as the pressure in the tank reaches a
point above 70 pounds it will force the diaphragm 18 back, against the pressure
of the spring 20, thus permitting the valve 27 to open under the pressure exerted

page_text: Thus the valve 21
by the spring 32 in closing or forcing the valve 28 to its seat.
will be held open while the valve 28 will be held closed. The fluid pressure
now enters the small radial holes 29 of the valve 27, passes through the tubular
or hollow valve stem, out through the radial holes 31, and thence through the
valve port 14 and pipe 13 into the cylinder 1 to act against the full area of the
adjacent side of the piston head 7, thereby overcoming the same pressure acting
against the reduced area of the opposite face of the piston head, and so forcing the
piston outward and holding it in that position until the fluid pressure in the tank
again falls to 70 pounds, or below. This outward movement of the piston actuates
the belt shifter, or the switch or lever, or a valve (not shown) in such direction
as to stop the pump. When the fluid pressure in the tank falls to 70 pounds, or
less, the spring 22 will force the diaphragm 18 towards the valve 27, thereby
closing said valve and holding it to its seat against the pressure of the spring 32
of the valve 28, and by thus seating the valve 27 the valve 28 will be held open
so that the pressure on the larger side of the piston 7 can flow back through
the pipe 13 and valve port 14, thence through the radial holes 31 into the hollow
stem of the valve 28, and out through the radial holes 30 of the said valve and
through the chamber 33 to the waste passage in the plug 34 at the end of the said
chamber. In the meantime the pressure in the cylinder 1 between the port 6 and
piston head 7 will force the piston back to its former position, as shown, and through
this movement of the piston the belt shifter will be actuated in such direction as
to carry the driving belt of the pump back onto the tight pulley for starting the
pump, or in like manner will actuate a valve, or a switch, or lever, for a similar
purpose. The same principle applies whether the motor is operating a hydraulic
pump, or an air pump, or compressor, and whether the starting and stopping is
to be effected through a belt shifter, or a lever, or an electric switch.
As shown the valves 27 and 28 are of such length in their stems or abutting
parts, that when the one is closed against its seat the opposite valve is forced open
or away from its seat a fixed distance, say th of an inch. The spring 32 is
held at an adjusted degree of compression by means of the screw plug 34, and its
strength and pressure should be sufficient to hold the valve 28 firmly against the
valve 27 with such power as to withstand the force of the required fluid pressure
acting against the area of the valve 28 in a direction to push it outward. Thus,
by a proper adjustment of the springs 20 and 32, the operation of the valve 15
will be automatic and immediately sensitive to any increase of fluid pressure
in the tank or reservoir above the standard to which the spring 20 may have been
adjusted.
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: -
First. In a fluid pressure actuated belt, lever, or switch shifter, the combination
with a piston to be connected with a device for controlling the operation of a
pump or engine to supply a pressure tank or reservoir, and a cylinder having
on that side or face of said piston which is of least area a port to be connected
with said pressure reservoir, of fluid-pressure-controlled valve mechanism to be
connected with the pressure reservoir and with said cylinder on that side or face
of said piston which is of larger area, and comprising opposed positively seating
and unseating valves arranged in such manner that the closing of either valve
exerts a direct pressure to open the other, substantially as described.
Second. In a fluid pressure actuated belt, lever, or switch shifter, the combina-
tion of a piston, an enclosing cylinder having a port on that side or face of said
piston which is of least area, and fluid-pressure-controlled three-way valve
mechanism adapted to communicate with said cylinder on that side or face of its
piston which is of larger area, and comprising opposed positively seating and
unseating valves so arranged that the closing of either valve exerts a direct
pressure to open the other, substantially as described.

page_text: Third. In a fluid pressure actuated belt or switch shifter, the combination with
a cylinder having a piston and provided with a port on that side or face of the
piston which is of least area, of a fluid-pressure-controlled three-way valve
mechanism connected with said cylinder on that side or face of the piston which
is of larger area, and comprising two oppositely seating valves arranged and
opposing each other in such manner that the closing of one valve causes the other
to open, substantially as described.
Fourth. In a fluid pressure actuated belt or switch shifter, the combination
with a cylinder having a piston and provided with a port on that side or face of
the piston which is of least area, of fluid-pressure-controlled valve mechanism
connected with said cylinder on that side or face of the piston which is of larger
area, and comprising two oppositely seated valves arranged and opposing each
other in such manner that the closing of one valve causes the other to open, and
two springs forcing said valves together from opposite directions, substantially as
described.
Fifth. In a fluid pressure actuated belt or switch shifter, the combination with
a cylinder having a piston and provided with a port on that side or face of the
piston which is of least area, of fluid-pressure-controlled valve mechanism con-
nected with said cylinder on that side or face of the piston which is of larger area,
and comprising two valve seats, two oppositely seating valves, two springs forcing
said valves together from opposite directions, and so adjusted that the closing
of one valve will cause the other to open, a flexible diaphragm between one of
said valves and its spring, means for adjusting the compression of said spring
against the diaphragm, and a casing for the diaphragm and valves provided with
suitable ports, substantially as described.
T
1 1
001
2000
W. P. THOMPSON & Co.,
11, Burlington Chambers, New Street, Birmingham,
Also of Liverpool, London and Manchester,
Patent Agents for the Applicant.