Improved Apparatus for Regulating and Utilizing Hydraulic Power.
Year: 1891

page_text: Date of Application, 9th Dec., 1891
Complete Specification Left. 7th Sept., 1892-Accepted, 22nd Oct., 1892
PROVISIONAL SPECIFICATION.
Improved Apparatus for Regulating and Utilizing Hydraulic
Power.
I, ROBERT HENRY THORPE of 27 Buckland Crescent, Belsize Park in the
County of Middlesex, Engineer, do hereby declare the nature of this invention to
be as follows:-
This invention relates to that class of apparatus designed for the purpose of
regulating the power and to a certain extent the quantity of high or main pressure
liquid employed for effecting the desired quantity of work, or in other words to
vary the resultant power depending upon the work it is called upon to perform,
the high or main pressure being assumed as remaining constant in either case.
The invention mainly consists of improvements upon the invention set out
in Specifications to Letters Patent No. 8961 of 1890, and in order that
the same may be clearly understood reference is made to the accompanying
drawings which form part of this Specification and in which Figures 1 to 5
illustrate the invention as applied to a single motor cylinder, and Figure 6 as
applied to a double or triple power motor from which it will be understood that it
may equally be applied to various forms of apparatus embodying a plurality of
motor cylinders.
In the drawings Fig. 1 represents the position of the parts when full power is
applied, and Fig. 2 with decreased power and reduced consumption of high or
main pressure liquid. In Figs. 3, 4 and 5 the position of one of the ports or
connections shewn in Figs. 1 and 2 is somewhat changed while still enabling the
same result to be attained, Fig. 3 representing the parts in position to admit full
power, while Fig. 4 indicates their position for reduced power with proportionate
reduction of high or main liquid consumption, while Fig. 5 represents the high or
main pressure as being entirely shut off, the liquid circulating from end A¹ to A
and to exhaust.
Considering first Figs. 1 and 2 it will be noted that end A¹ of the cylinder is
connected to main or supply pipe D by pipe S, the inflow being governed by stop
valve E, and operating valve F, the latter also governing the direct exhaust
through pipe G from end A' of cylinder. A branch pipe I with regulating
valve connects end A' of cylinder through pipes S and I with cylinder behind
piston K. A branch pipe H with regulating valve P connects cylinder J in front
of piston K with main or other source of supply D at a point outside of valve F,
so that the full main pressure may be exerted thereon.
When
The valve L which is controlled by pressure exerted on piston K opens
connection from the end A to discharge as shewn in Fig. 1 through pipes M and O,
or to end A' of cylinder through pipes M, N and S as shewn in Fig. 2.
the valves are in position shewn in Fig. 1 full pressure entering through D is
exerted behind piston B, the other end of the cylinder being open to discharge X
by exhaust G through valve L by pipes M and O, initial pressure being exerted
behind piston K through pipes S and I, and full main pressure in front of piston K
through pipe H. The piston B having completed its desired stroke, valve F is
moved, shutting off supply through D, opening direct exhaust from behind B to G,
as clearly shewn in Fig. 5, when the pressure behind K being relieved, the direct
pressure from main in front of K overcomes friction of valve L which is moved
in the direction of least resistance over to the position shewn in Fig. 2, in which
position it will remain until piston B is called upon to perform work which requires
the larger power. On return stroke of piston B the water in end A' is caused to

page_text: flow back through pipe S and operating valve F to exhaust pipe G, enough
passing through check valve R (which will allow water to pass from G to M but
not to return) to fill end A, the remainder which is equal to the quantity displaced
by piston rod C going to discharge X.
With the parts as shewn in Fig. 2 the apparatus is adapted to work at decreased
power with a decreased consumption of high or main pressure water, as the ends A
and A¹ of cylinder are both open to pressure, the power exerted being proportionate
to the sectional area of piston rod C. So long as the work to be done by C can
be effected at the reduced power so long will the pressure in front of K be sufficient
to hold valve L in position shewn in Fig. 2 against pressure behind K, which as
is well known will vary in proportion to resistance of piston B, or of the work
to be done. The area of piston K can be proportioned so that full effective
power shall only be put on piston B when the resistance or work to be done
calls for a pressure above a certain number of pounds per square inch.
For the purpose of illustration let it be assumed it will take a pressure of
500 lbs. per square inch behind K to equal the pressure from main plus the
friction, then so long as the work required to be done by piston B does not
require a greater number of pounds per square inch, so long will valve L remain
in position shewn in Fig. 2, and as the work is being done the water displaced by
travel of B will be passed through M, L, N, F and S to other side, thereby only
using the water required for the first or reduced power of the motor.
For the purpose of further illustration let it be assumed that the work to be
done requires a greater number of pounds per square inch than will be sufficient
to overcome the pressure from main on K plus friction, then the initial pressure
per square inch will rise according to the resistance of piston B and be transmitted
through pipes S and I to cylinder J, and will cause K to travel in direction of
least resistance or over to the position shown in Fig. 1, thus opening the end A
of cylinder to exhaust G through pipes M and O, and causing the apparatus to
work on the larger power; as soon as the work has been done and the motor
stopped initial pressure behind K is relieved and the valve L is automatically
moved back into its normal position as shown in Fig. 2. When moving from the
small to larger power as soon as valve L has moved forward sufficiently to throttle
the outlet N without sufficiently opening exhaust port O the resistance to B in
cylinder will be increased, and it will be impossible for this reason for the valve
to return whilst piston B is moving forward performing work, thus the larger
power being provided will not change until motor comes to rest when it will be
free to return to the smaller power.
If valve L be constructed so that port N is entirely cut off from pipe M before
the latter is put into communication with O, then the result would be as stated,
but it may be so constructed that there is a slight passage between 0 and M,
and M and N when the valve is midway, said passage being insufficient to allow
water from the main to go to waste, but yet sufficient to allow the water from M
to take the direction O or N, without materially checking the motion of piston B
in the cylinder.
The special value of valve R is to allow water from the exhaust or discharge to
pass into end A of the cylinder whenever piston B shall be on the return stroke,
thus avoiding the possibility of there ever being a vacuum in end A of said
cylinder whatever the position of valve L. When piston B is returning there
will always be sufficient water coming through pipe S to fill end A of cylinder,
but notwithstanding I generally prefer to use a discharge tank placed in such a
position that the water shall run from it by gravity through check valve R into
said end.
When it is desired to obviate any possibility of valve L closing pipe N and
failing to open the discharge from M through O to G, a connection may be made
directly from pipe M to pipe S, such connection V being provided with a check
valve T. which will permit a flow from M but not from S. Such a connection is
illustrated in Figs. 3, 4, and 5, and renders the use of pipe N unnecessary. +

page_text: If it be assumed that valve F has been moved allowing pressure from the
main to be exerted behind piston B through pipe S, and that the resistance of
piston B has caused initial pressure behind K in cylinder J to be raised
sufficiently to overcome the pressure from the main in front of K plus the friction,
then valve L would be moved over to position represented in Fig. 3, thus
opening the end A. of the cylinder to exhaust G through M and O, and the
motor would then be working on the larger power. After the motor has been
stopped the initial pressure behind K being relieved valve L is automatically
moved back as already described, to the position shown in Figs. 4 and 5, cutting
off communication from front of piston B to exhaust G.
If it be assumed that the pressure from the main is being exerted behind
piston B but the resistance given is not enough to raise initial pressure behind K
sufficiently to overcome the resistance in front, then the water which is in front
of piston B would be compressed and owing to the difference in area of piston B
on opposite sides the piston will travel forward, the water displaced by such travel
being compelled to pass to end A¹ of the cylinder through pipe V and check
valve T, the valves L and F being in position shown in Fig. 4, and the motor
working on the lower power with decreased consumption of high or main
pressure water.
Instead of check valve T, communication may be made between the ends of
cylinder by means of valves W placed in piston B, or by so constructing the
piston and packing that the water can pass from the end A to end A' of the
cylinder.
In Fig. 6 where the invention is shown as applied to a double or treble
power motor the action would be as follows:-For the first power water being
admitted through pipe D and operating valve F through pipes N and valve L
to cylinder A beneath piston B; if the power acquired approaches closely to
that of which the ram is capable, the initial pressure will rise and act upon
piston K in cylinder J, thus causing valve L to move forward and close_passage N¹
and at the same time opening a passage through N and M to second power, or
top of ram Y. If this power be still too little for the work it has to perform,
piston K will move further forward overcoming the constant pressure in front of
it with the initial pressure behind and moving valve L forward so that the power
through S will be open to cylinder A under piston B. Thus the main pressure
will be employed beneath B and on top of Y, giving full power of the machine.
To enable ram or piston B to return valve F would be so moved that the water
in D would be cut off, and afterwards ports e, f, which lead around valve F to
passages M and S, and thence to cylinder A and to top of ram Y, would be put
in connection with the exhaust G, and thus a discharge entirely independent of
valve L may be obtained.
Dated the 9th day of December 1891.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Applicant's Agent.
COMPLETE SPECIFICATION.
Improved Apparatus for Regulating and Utilizing Hydraulic
Power.
I, ROBERT HENRY THORPE, of 27 Buckland Crescent, Belsize Park, in the
County of Middlesex, 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:-
This invention relates to that class of apparatus designed for the purpose of
regulating the power and to a certain extent the quantity of high or main pressure
liquid employed for effecting the desired quantity of work, or in other words

page_text: to vary the resultant power depending upon the work it is called upon to
perforin, the high or main pressure being assumed as remaining constant in
either case.
The invention mainly consists of improvements upon the invention set out
in Specifications to Letters Patent No. 8961 of 1890, and in order that the
same may be clearly understood reference is made to the drawings filed with the
Provisional Specification in which Figures 1 to 5 illustrate the invention as
applied to a single motor cylinder, and Figure 6 as applied to a double or triple
power motor from which it will be understood that it may equally be applied to
various forms of apparatus embodying a plurality of motor cylinders.
In the drawings Fig. 1 represents the position of the parts when full power is
applied, and Fig. 2 with decreased power and reduced consumption of high or
main pressure liquid. In Figs. 3, 4 and 5 the position of one of the ports or
connections shewn in Figs. 1 and 2 is somewhat changed while still enabling the
same result to be attained, Fig. 3 representing the parts in position to admit full
power, while Fig. 4 indicates their position for reduced power with proportionate
reduction of high or main liquid consumption, while Fig. 5 represents the high or
main pressure as being entirely shut off, the liquid circulating from end A¹ to A
and to exhaust.
Considering first Figs. 1 and 2 it will be noted that end A' of the cylinder is
connected to main or supply pipe D by pipe S, the inflow being governed by stop
valve E, and operating valve F, the latter also governing the direct exhaust
through pipe G from end A¹ of cylinder. A branch pipe I with regulating valve Q
connects end A' of cylinders through pipes S and 1 with cylinder J behind
piston K. A branch pipe H with regulating valve P connects cylinder J in front
of piston K with main or other source of supply D at a point outside of valve F, so
that the full main pressure may be exerted thereon.
The valve L which is controlled by pressure exerted on piston K opens
connection from the end A to discharge as shewn in Fig. 1 through pipes M and O,
or to end A' of cylinder through pipes M, N and S as shewn in Fig. 2. When
the valves are in position shewn in Fig. 1 full pressure entering through D is
exerted behind piston B, the other end of the cylinder being open to discharge X
by exhaust G through valve L. by pipes M and O, initial pressure being exerted
behind piston K through pipes S and I, and full main pressure in front of piston K
through pipe H. The piston B having completed its desired stroke, valve F is
moved, shutting off supply through D, opening direct exhaust from behind B to G,
as clearly shewn in Fig. 5, when the pressure behind K being relieved, the direct
pressure from main in front of K overcomes friction of valve L which is moved in
the direction of least resistance over to the position shewn in Fig. 2, in which
position it will remain until piston B is called upon to perform work which requires
the larger power. When it is desired that the forward motion of piston K shall
be rapid but its return motion slow it is only necessary to connect one end of a
pipe provided with a one way valve to pipe I outside and the other end inside of
valve Q. This arrangement will permit a full flow of initial pressure liquid
behind K while when said piston is returning the discharge of initial pressure liquid
is governed by the opening in valve Q thus governing the speed at which valve L
is capable of moving. On return stroke of piston B the water in end A' is caused
to flow back through pipe S and operating valve F to exhaust pipe G, enough
passing through check valve R (which will allow water to pass from G to M but
not to return) to fill end A, the remainder which is equal to the quantity displaced
by piston rod C going to discharge X.
With the parts as shewn in Fig. 2 the apparatus is adapted to work at decreased
power with a decreased consumption of high or main pressure water, as the ends A
and A' of cylinder are both open to pressure, the power exerted being proportionate
to the sectional area of piston rod C. So long as the work to be done by C can
be effected at the reduced power so long will the pressure in front of K be
sufficient to hold valve L in position shewn in Fig 2 against pressure behind K,

page_text: which as is well known will vary in proportion to resistance of piston B, or of the
work to be done. The area of piston K can be proportioned so that full effective
power shall only be put on piston B when the resistance or work to be done calls
for a pressure above a certain number of pounds per square inch.
For the purpose of illustration let it be assumed it will take a pressure of
500 lbs. per square inch behind K to equal the pressure from main plus the friction,
then so long as the work required to be done by piston B does not require' a
greater number of pounds per square inch, so long will valve L remain in position
shewn in Fig. 2, and as the work is being done the water displaced by travel of B
will be passed through M, L, N, F and S to other side, thereby only using the
water required for the first or reduced power of the motor.
For the purpose of further illustration let it be assumed that the work to be
done requires a greater number of pounds per square inch than will be sufficient
to overcome the pressure from main on K plus friction, then the initial pressure
per square inch will rise according to the resistance of piston B and be transmitted
through pipes S and I to cylinder J; and will cause K to travel in direction of
least resistance or over to the position shown in Fig. 1, thus opening the end A
of cylinder to exhaust G through pipes M and O, and causing the apparatus to
work on the larger power; as soon as the work has been done and the motor
stopped initial pressure behind K is relieved and the valve L is automatically
moved back into its normal position as shown in Fig. 2. When moving from the
small to larger power as soon as valve L has moved forward sufficiently to throttle
the outlet N without sufficiently opening exhaust port O the resistance to B in
cylinder will be increased, and it will be impossible for this reason for the valve
to return whilst piston B is moving forward performing work, thus the larger
power being provided will not change until motor comes to rest when it will be free
to return to the smaller power.
If valve be constructed so that port N is entirely cut off from pipe M before
the latter is put into communication with O, then the result would be as stated,
but it may be so constructed that there is a slight passage between O and M, and
M and N when the valve is mid way, said passage being insufficient to allow water
from the main to go to waste, but yet sufficient to allow the water from M to take
the direction O or N, without materially checking the motion of piston B in the
cylinder.
The special value of valve R is to allow water from the exhaust or discharge to
pass into end A of the cylinder whenever piston B shall be on the return stroke,
thus avoiding the possibility of there ever being a vacuum in end A of said
cylinder whatever the position of valve L. When piston B is returning there will
always be sufficient water coming through pipe S to fill end A of cylinder, but
notwithstanding I generally prefer to use a discharge tank placed in such a
position that the water shall run from it by gravity through check valve Rinto
said end.
When it is desired to obviate any possibility of valve L closing pipe N and
failing to open the discharge from M through O to G, a connection may be made
directly from pipe M to pipe S, such connection V being provided with a check
valve T which will permit a flow from M but not from S. Such connection
is illustrated in Figs. 3, 4 and 5, and renders the use of pipe N unnecessary.
If it be assumed that valve F has been moved allowing pressure from the main
to be exerted behind piston B through pipe S, and that the resistance of
piston B
has caused initial pressure behind K in cylinder J to be raised sufficiently to
overcome the pressure from the main in front of K plus the friction, then valve L
would be moved over to position represented in Fig. 3, thus opening the end A
of the cylinder to exhaust G through M and O, and the motor would then be
working on the larger power. After the motor has been stopped the initial
pressure behind K being relieved valve L is automatically moved back as already
described, to the position shown in Figs. 4 and 5, cutting off communication from
front of piston B to exhaust G.

page_text: If it be assumed that the pressure from the main is being exerted behind
piston B but the resistance given is not enough to raise initial pressure behind K
sufficiently to overcome the resistance in front, then the water which is in front
of piston B would be compressed and owing to the difference in area of piston B
on opposite sides the piston will travel forward, the water displaced by such travel
being compelled to pass to end A' of the cylinder through pipe V and check
valve T, the valves L and F being in position shown in Fig. 4, and the motor
working on the lower power with decreased consumption of high or main pressure
water.
Instead of check valve T communication may be made between the ends of
cylinder by means of valves W placed in piston B, or by so constructing the piston
and packing that the water can pass from the end A to end A' of the
cylinder.
If this
In Figure 6 where the invention is shown as applied to a double or treble power
motor the action would be as follows:-For the first power water being admitted
through pipe D and operating valve F through pipes N and valve L to cylinder A
beneath piston B; if the power acquired approaches closely to that of which the
ram is capable, the initial pressure will rise and act upon piston K in cylinder J,
thus causing valve L to move forward and close passage N and at the same time
opening a passage through N and M to second power, or top of ram Y.
power be still too little for the work it has to perform, piston K will move further
forward overcoming the constant pressure in front of it with the initial pressure
behind and moving valve L forward so that the power through S will be open to
cylinder A under piston B. Thus the main pressure will be employed beneath B
and on top of Y, giving full power of the machine. To enable ram or piston B
to return valve F would be so moved that the water in D would be cut off, and
afterwards ports e, f, which lead around valve F to passages M and S, and thence
to cylinder A and to top of ram Y, would be put in communication with the
exhaust G, and thus a discharge entirely independent of valve L may be
obtained.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. The combination with a motor cylinder piston, channels and a valve
governing the inlet to and exhaust from the working end of said cylinder of a
valve automatically operated by the difference between main and initial pressure
governing the passages from the piston rod end of said cylinder to exhaust and
to the working end of said cylinder and a supplementary passage and valve
connecting said latter passage with the exhaust, substantially as set forth.
2nd. The combination with a motor cylinder piston channels and a valve
governing the inlet and exhaust from the working end of said cylinder of a
valve governing the discharge from the piston rod end of the cylinder, said valve
being automatically operated solely by the difference between the main pressure
and initial pressure even if these vary from time to time, substantially as
set forth.
3rd. The combination with a motor cylinder piston channels and a valve
governing the inlet and exhaust from the working end of said cylinder and a valve
automatically operated by the difference between main and initial pressure governing
the exhaust from the piston rod end of said cylinder of supplementary passage and
valves between the exhaust and the piston rod end of said cylinder substantially as
set forth.
4th. The combination with a power cylinder piston channels a valve governing
the inlet and exhaust of the working end and a piston valve automatically operated
by the difference between main and initial pressure governing the exhaust of the
piston rod end, of regulating valves interposed between the supply pipe and the
piston rod end of the piston valve cylinder and between the working end of

page_text: said cylinder and the working end of the power cylinder, substantially as
set forth.
5th. The combination with a power cylinder and piston of a valve governing.
the exhaust from the piston rod end of the cylinder and automatically operated
by the difference between main and initial pressure, and a supplemental valve
interposed between the piston rod end and the working end of said cylinder,
substantially as set forth.
Dated the lot contab 1000
PHILIP M. JUSTICE, Fel. Chart. Inst. P.A.,
55 & 56, Chancery Lane, London, Agent for the Applicant.