cre Denting COMPTROLLER'S DECISION
Year: 1878

page_text: SAMUEL CHATWOOD of the Lancashire Safe & Locks Works, Bolton in the County
of Lancaster seek leave to amend the Specification of Letters Patent No. 2600 of
1878, as shown in red ink in the copy of the original specification hereunto
annexed:-
My reasons for making this amendment are as follows :—
Parts of the invention are not of sufficient importance to lead me to retain any
claim in respect to the same; and as to the part of the invention which I desire to
retain I wish to explain and by way of disclaimer to render more clear the limits
within which my claim was and is intended to be confined.
In the Matter of an Application by Samuel Chatwood for leave to amend the
Specification of Letters Patent No 2600 dated the 28th day of June 1878:
Turn DanLICA's DecreTAV
In the Matter of an Application by Samuel Chatwood for leave to amend the
Specification of Letters Patent No 2600 dated the 28th day of June 1878:
The Denting COMPTROLLER'S DECISION
I hereby grant leave to the above named Samuel Chatwood to amend the said

page_text: LETTERS PATENT to Samuel Chatwood, of 120, Cannon Street, in the City of
London, in the County of Middlesex, Bank Engineer, for the Invention of
"IMPROVEMENTS IN HYDRAULIC ARRANGEMENTS FOR LIFTING AND LOWERING,
AND OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Samuel Chatwood at the
Office of the Commissioners of Patents on the 28th June 1878.
SAMUEL CHATWOOD, of 120 Cannon Street in the City of London in the County
of Middlesex Bank Engineer. "IMPROVEMENTS IN HYDRAULIC ARRANGEMENTS
FOR LIFTING AND LOWERING AND OTHER PURPOSES."
My Invention for improvements in hydraulic arrangements for lifting and
lowering and other purposes consists mainly as follows :-
One of the objects aimed at by my Invention is to enable a large and tolerably
constant load on the lifting ram or cylinder to be raised or lowered when desirable,
as in the case of books, cash, and such like, belonging to bankers' and others.
In carrying out this part of my Invention, I adopt mainly the following arrange-
ments :-
The cylinder of the lifting ram is connected by a pipe with the balancing cylinder
the respective areas of the two being in suitable proportion. When the ram of one
cylinder is raised, the ram of the other is lowered, in exactly the same way as
weights on a scale beam. Supposing that the weight on the lifting ram is one ton;
then to balance it on the other cylinder, a weight must be placed bearing such a
proportion to the ton weight as is represented by the direct proportion of the areas
of the cylinders. If now it is desirable to raise the ram of the lifting cylinder
(supposing it to be in its lowest position) a further weight must be applied to the
balancing cylinder ram, to overcome the friction of the packings &c. of the two
cylinders, the friction of the water passing through the connecting pipe being at
slow speed almost nil.
The weight having been applied as above stated, and the ram of the lifting
cylinder raised; then to lower it again this extra weight that has been applied to
the balancing cylinder must be removed, and a corresponding increase of weight
must be brought to bear on the ram of the lifting cylinder, in order to overcome as
before, the friction of the apparatus. Now this extra balanced weight may virtually
be applied to the lifting cylinder by removing a corresponding weight from the
balancing cylinder, leaving the lifting cylinder untouched, as regards the removal of
its weight. Suppose now that the ram of the balancing cylinder in passing out of
its gland, is attached to another cylinder this other cylinder being inverted in such
a way that it covers or partially covers the balance cylinder proper, and at the same
time the upper portion of the balance cylinder is enlarged outside, so as to form a

page_text: water-tight joint, with the interior of the inverted cylinder. Now if the inverted
cylinder, which is carried by the ram of the balancing cylinder, is made very thick,
or is arranged to carry weight, its weight can be so adjusted as to always raise the
lifting cylinder ram, and if the ram of the lifting cylinder has been raised in this
manner and it is required to lower it again, then in order to remove some of the
weight from the balancing cylinder ram, water at a comparatively low pressure is
admitted into the space between the bottom of the inverted cylinder and the top of
the balancing cylinder. Now as this inverted cylinder must from its position have
an area greatly larger than the balancing ram, which must of course be subtracted.
from it a considerable upward pressure is exerted by the low-pressure water intro-
duced in the inverted cylinder; this water pressing upwards virtually removing a
portion of the weight from the balancing cylinder and causing the lifting ram to
descend, the balance having been disturbed to its advantage.
The inverted cylinder may or may not be used according to circumstances.
If desirable, a small supplementary cylinder may be used to destroy the
unbalanced weight on the balancing cylinder and throw the advantage on the side
of the lifting cylinder.
The second part of my Invention relates to the construction of hydraulic elevators
and automatic valve gear and is mainly as follows:-Where an automatic lift
regulator applicable to raising and lowering is required, the arrangements consist
principally of two single-acting hydraulic cylinders, provided with pistons and
suitable piston rods. On each piston rod, or on an extension of the same, is a
counterbalance weight to cause the piston and its connections to fall when the water
pressure is removed from beneath the pistons of the two cylinders. The high-
pressure water is supplied to the underside of the pistons by a suitable pipe and
as one main pipe supplies both cylinders, the pressure of the water causes both
pistons to rise at the same time. A pipe for draining off any water that may leak
through during the time the high-pressure water is acting upon the under side of
the piston is supplied. The high-pressure pipe passes on its way to the main supply
trough a three-way cock, the said cock having two ways placed in diametrically
opposite directions in the body or case of the cock, and one way at the bottom of
the body or case of the cock, in the centre line of the plug or spindle of the cock.
The high-pressure pipe is fitted to this latter opening, and as the plug of the cock
is hollow, and has but one opening in its sido, communication can be made (by
turning the spindle round half a revolution) with either of the openings in the side
of the body or case of the cock. One of these openings in the side of the case of
the cock is in communication with the high-pressure main, the other with the drain
passing away. It is therefore evident that by turning the spindle of the cock
round half a revolution either way the water can be either admitted or discharged
from the cylinders as desired.
A contraction of the piston rod of the cylinder is connected in any convenient
manner with a sleeve or hollow piston valve which is so arranged as to open in the
middle position to supply, and in the extreme up and down positions to waste, so
that according to the position of the valve, the left cylinder is either supplied with
high-pressure water, or the high-pressure water is discharged from it. By suitable
mechanism, the cylinder is connected with the lift. Tho lift when raised, rests upon
supporting bolts or slippers sliding in suitable bracket, these slippers, together with
the sleeve valve being worked by the cylinders before described.
The extension of the piston rod of one of the cylinders passes through a peculiarly
formed slot in the back end of the slipper the piston rod at this point carrying a
button or collar, so arranged that when the slipper is fully out, the rod can pass
right upwards clear of the slipper; but when the slipper is in the button and
therefore the piston rod cannot pass right up through the slipper, but is held about
midway in its stroke, or in such a position that the sleeve valve is open to supply
the lift cylinder with high-pressure water. When the valve is in this position,
the lift is rising, and continues to rise until a fixed pin in the lift comes in contact
with the end of a releasing catch; when this catch is raised sufficiently higb, the

page_text: supporting bolts or slippers are shot out by one of the cylinders, and as soon as
they are fully shot out the button on the piston rod is released from its slot, and
the rod being left free, the cylinder draws it upwards, opening the sleeve valve to
waste, and letting the lift, down again, to rest upon the slippers or bolts. On
exhausting the water from the cylinders, the lift is first raised to take the weight
off the bolts or slippers, which are then withdrawn, and the lift descends to its first
position.
The third part of my Invention relates to an improved hydraulic engine, for
automatically keeping up the accumulators of hydraulic elevators, lifts, or cranes,
and is mainly as follows:-The engine is constructed with cylinder, and piston, and
tail piece working with the piston, through a stuffing box, the piston valve having a
reduced piston.
The engine may be single-acting and in combination with a pump, but it may
also be made double-acting and entirely independent of any other contrivance. It
acts as follows:-The water entering at the pump suction is supposed to come in
with sufficient pressure to drive the engine piston downwards. Now when the
piston has travelled a certain distance down, an opening in the tail piece will come
opposite an opening in the cylinder and another opening comes opposite a corre-
sponding opening in the same.
The last-mentioned opening, or a branch is supplied with high-pressure water,
which enters at one of the openings, when in position before described, and passes
along to the under side of the piston of the valve raising it until the space left is
opposite a port in the cylinder. The high-pressure water for driving the cylinder
now rushes in, and raises the piston, when an opening in the tail piece comes into
such a position that the water contained in the end of the valve box is discharged
down through the hollow tail piece. The piston is brought back by the pump inlet,
and the cycle of operations goes on as before.
It should be noted that the openings in the tail piece are made adjustable, to suit
various speeds.
This part of my Invention may also be used for other purposes where .hydraulic
power is available,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Samuel Chatwood in the Great Seal Patent Office on the 28th
December 1878.
SAMUEL CHATWOOD of 120 Cannon Street in the City of London in the County
of Middlesex Bank Engineer. "IMPROVEMENTS IN HYDRAULIC ARRANGEMENTS
FOR LIFTING AND LOWERING AND OTHER PURPOSES."
My Invention for improvements in hydraulic arrangements for lifting and
lowering and-other purposes consists substantially, as follows:-
One of the objects aimed at by my Invention is to enable a large and tolerably
constant load on the lifting ram or cylinder to be raised or lowered when desirable,
as in the case of books, cash and such like, belonging to bankers and others.
In carrying out this part of my Invention, I adopt the following arrange-
ments:
The cylinder of the lifting ram is connected by a pipe with the balancing
cylinder, the respective areas of the two being in suitable proportion. When the
ram of one cylinder is raised the ram of the other is lowered in exactly the same
way as weights on a scale beam. Supposing that the weight on the lifting ram is
one ton, then to balance it on the other cylinder a weight must be placed bearing
auch a proportion to the ton weight as is represented by the direct proportion of
the areas of the cylinders. If now it is desirable to raise the ram of the lifting
cylinder (supposing it to be in its lowest position) a further weight must be applied
to the balancing cylinder ram, to overcome the friction of the packings &c. of the
two cylinders, the friction of the water passing through the connecting pipe being
at slow speed almost nil.
The weight having been applied as above stated and the ram of the lifting
cylinder raised, then to lower it again, this extra weight that has been applied to
the balancing cylinder must be removed and a corresponding increase of weight
must be brought to bear on the ram of the lifting cylinder, in order to overcome as
before the friction of the apparatus. Now this extra balancing weight may
virtually be applied to the lifting cylinder by removing a corresponding weight
from the balancing cylinder, leaving the lifting cylinder untouched as regards the
removal of its weight. Suppose now that the ram of the balancing cylinder in
passing out of its gland is attached to another cylinder, this other cylinder being
inverted in such a way that it covers or partially covers the balance cylinder
proper and at the same time the upper portion of the balance cylinder is enlarged
outside so as to form a water-tight joint with the interior of the inverted cylinder.
Now if the inverted cylinder which is carried by the ram of the balancing
cylinder is made very thick or is arranged to carry weight, its weight can be so
adjusted as to always raise the lifting cylinder ram, and if the ram of the
lifting cylinder has been raised in this manner, and it is required to lower it

page_text: ,
again then in order to remove some of the weight from the balancing cylinder
ram, water at a comparatively low pressure is admitted into the space between the
bottom of the inverted cylinder and the top of the balancing cylinder. Now as
this inverted cylinder must from its position have an area greatly larger than that
of the balancing ram which area must of course be subtracted from it a consi-
derable upward pressure is exerted by the low-pressure water introduced in the
inverted cylinder, this water pressing upwards virtually removing a portion of the
weight from the balancing cylinder ram and causing the lifting ram to descend the
balance having been disturbed to its advantage.
The inverted cylinder may or may not be used according to circumstances.
If desirable a small supplementary cylinder may be used to destroy the un-
balanced weight on the balancing cylinder and throw the advantage on the side of
the lifting cylinder.
The second part of my Invention-relates to the construction of hydraulie
elevators--and--automatic valve--gear, and is effectuated--as follows:-Where--an
automatic-lift-regulator-applicable to raising and lowering-is-required the-arrange
ments consist-principally of two single-acting-hydraulio-eylinders--provided with
pistons and suitable piston rode. On each piston red, or on an extension of the
same-is-a-counterbalance-weight, to cause the piston and its connections to fall
when the water-pressure-is-removed-from-beneath the pistons of the two-cylinders.
The high-pressure-water-is-supplied-to-the-under-side-of--the-pistons-by-a-suitable
pipe, and, as one main-pipe-supplies both eylinders, the pressure of the-water-causes
beth-pistons-to-rise-at-the-same-time. A pipe for draining off any water that may
leak-through-during the time the high-pressure water is acting upon the under-side
of the piston-is-supplied. The high-pressure pipe passes on its way to the main
supply through a three-way-cock the said cock having two-ways placed in diamet
rically opposite directions in the body or ease of the cock, and one-way at the
bottom of the body-or-ense-of-the-cock in the centre line of the plug or spindle-of
the-eeek. The-plug-of-the-cock-is hollow, and has but one-opening-in-its-side, se
that communication can be made-(by-turning the-spindle-round half a revolution)
with either of the openings in the side of the body-or-ease of the cock.-One-of
these-openings-in-the-side-of-the-ease of the cook is in communication-with-the
high-pressure-main-the-other-with-the-drain-passing away. It is therefore-evident
that by turning the spindle of the cock round half a revolution-either way, the
water-can-be-either admitted or discharged from the cylinders,-as-desired.
A-continuation of the piston-rod-of-the-cylinder is connected-in-any-convenient
manner-with-a-sleeve or hollow piston valve, which is so-arranged as-to-open-in-the
middle-position-to supply, and in the extreme up and down positions-to-waste, so
that according to the position of the valve, the lift cylinder is either-supplied with
high-pressure-water, or the high-pressure water is discharged-from-it. By suitable
mechanism, the cylinder is connected with the lift. The lift-when-raised rests upon
supporting bolts--or--slippers, sliding in suitable bracket, -these-slippers, together
with-the-sleeve-valve, being worked-by-the-cylinders-before-described.
The extension of the piston rod of one of the cylinders passes through a peculiarly
formed--slot--in-the-back-end-of--one-of-the-slippers, the piston rod at this point
earrying-a-button-or-collar-so-arranged that when the slipper is fully-out,-the-red
ean-pass-right-upwards-clear of the slipper, but-when-the-slipper-is-in-the-button,
and-therefore-the-piston rod-cannot-pass-right-up-through-the-slipper, but is held
about-midway-in its stroke, or in such a position that the sleeve valve-is-open-to
supply the lift-eylinder--with-high--pressure-water. When the valve is in this
position, the-lift is rising-and-continues-to-rise-until a fixed-pin-in-the-lift-comes in
contact-with-the-end of a releasing eateh. When this-eateh is raised-sufficiently
high-the-supporting bolts-or-slippers-are-shot-out by one-of-the-eylinders-and-us
soon as they-are-fully-shot-out-the-button-on-the-piston-rod-is-released-from-its-clot,
and--the--rod--being-left-free, -the-eylinder-draws-it-upwards--opening--the--sleeve
valve-to-waste--and--letting the lift down-again-to rest upon the slippers or belts.
On--exhausting-the-water-from-the--eylinders the lift is first raised-to-take--the

page_text: Fig. 1 is sectional elevation of balancing cylinder arrangements. Fig. 2, plan of
Fig. 1. Fig. 3 sectional elevation of modified form of doublo cylinder.
A is the ram of the lift B, the cylinder being shown inverted, after the manner
described by mo in the Specification of my Patent No. 3626 A.D. 1875. This
cylinder is connected to the balancing cylinder by a pipe C, of suitable size
and strength. The pipe is shown to enter the balancing cylinder D at the
bottom.
As will be seen this cylinder is also provided with a ram or plunger E, which
works water-tight through its collar or stuffing box F, at the top of the cylinder.
The top of this ram or plunger carries the outer cylinder G, with its weights H.
The whole; that is, the interior ram, together with the outer cylinder and its weights,
rise at the same time. The outer cylinder G is connected with the towns or other
available pressure of water by the supply pipe I.
The action of the apparatus is as follows:-Suppose the lift or other contrivance
at B to weigh any given weight, say one ton, and it is considered desirable or it
may be considered necessary to raise it or lower it on a small ram as at A, the
pressure available whether from the street main or otherwise being of comparatively
low pressure. The cylinder and pipe joining them are first filled with the requisite
amount of water or other desirable fluid one of the rams being right home or at its
lowest position the other being right out or at its highest position (as shown in the
Drawing). Supposing the lift raised weights are now applied to the exterior
cylinder G to balance the weight of the lift B.
These weights will of course require to have a proportion directly in accordance
with the areas of the two rams A and E, if any force is now applied to either the
lift or the balancing apparatus, the balance will be destroyed, supposing the force
sufficient to overcome the friction of the collars &c.; the lift will move up or down,
according to the direction in which the force is applied. Suppose now that a
further weight is applied on the exterior cylinder G sufficient to raise the lift and

page_text: •
anything it may contain. Then to lower it again the available water pressure is
admitted through the pipe I and acting upon the under side of the exterior cylinder
cover raises the cylinder with its weights and at the same time lowers the lift and
its contents. The proportion of the exterior cylinder area will of course require to
be varied according to the intensity of the available pressure of water.
Another method of carrying out the balancing is as follows (see Fig. 3). A is
the balancing cylinder B is the weight or motive-power cylinder. The balancing
cylinder A is connected as before by the pipe C to the lift to be raised. The
pipe D is always open to the available water pressure and constitutes in this case
the weighted cylinder previously described in the last arrangement. The pressure
upon the piston E is therefore sufficient always to raise the lift with its load.
When it is required to lower the lift, the available pressure is admitted on the other
side of the piston E and the lifting pressure reduced in sufficient proportion to
allow the lift to descend.
I desire to explain that in my arrangement the size of the lift ram is quite
independent of the available water pressure and it should be such as is suitable
having regard only to the mechanical requirements as to strength and so forth-
Any convenient length may be given to the balancing cylinder but its capacity
should be somewhat greater than that of the lift cylinder, these cylinders together
with the connecting pipe form a closed system.
The load to be applied to the ram or piston of the balancing cylinder should be
such as to allow a preponderance sufficient to give a suitable speed to the lift ram
when by the opening of the controlling valve the preponderance is permitted to
operate.
The driving area on which the available water pressure is allowed to operate
should also be so proportioned as to give a suitable speed in the contrary direction.
Sometimes as already stated I use a small supplementary cylinder of sufficient
driving area.
The essential characteristics of my lifts thus are that the load is applied at the
balancing cylinder and operates on the lift through the water or other fluid
enclosed in the balancing cylinder and the lift cylinder with their connecting
pipe; and also that the available water pressure by which the lift is worked is
applied to operate primarily on the balancing arrangement and indirectly or
through the medium of the enclosed water or other fluid upon the lift and lifting.
ram and cylinder.
These are both essential features in my arrangement and I disclaim all lifts in
which both of these features are not found.
Fig. 4-sectional-elevation--illustrating the second part of my Invention--Fig.-5
side view and Fig. 6-plan-of-one-of the slippers showing slot-in-same.
A and B are the two single neting cylinders provided with pistons and rods C
and D, E and F. To these rods are attached weights C and H equal or nearly-so
to half the lifting power of the pistons. The piston-rods-are-continued-down-past
the-weights, and one, the rod of the cylinder B-is-connected-to-a-piston or equi-
librium-valve J so constructed that it is open to exhaust at its highest and lowest
positions-respectively, and open-to-supply-at-its-mid-position. On the piston rod F
is-a-dise-or-button-K-securely fastened thereon. The piston rod D of the cylin
der A-is--connected by a lever and weight shaft as shewn with the slippers or
bolts L and M. These bolts shoot out when the lift is at the right height and the
lift-rests-upon-them-during-such-time us it may be required raised. O-is-a-pin-in
the lift which as the lift-rises, engages with the lever N and lifts the holding pin l'
out of the bolt L allowing the weight G-to-descend and sheet out the bolts.
The arrangements net as follows: If it is required to lower the lift after it has
been raised-and-is resting on the bolts L M the bigh-pressure water-is-admitted
to-the-under-side of the two-pistons E and C. The piston C cannot rise because
the weight of the lift keeps the bolts M & L from moving but the piston E rises
until the button K-comes against the under-side of the grooved slot K' in the
slipper-L.--This-raises at the same time the piston of the valve J-to-supply. High-

page_text: pressure-water-is admitted by this valve to the lift-eylinder and the lift is raised.
As soon however us the weight is removed from the bolts the piston C commences to
rise-and-draws them back until the enlarged opening K2 in the slot of the bolt L
comes opposite the button-K-on-the-piston rod F the piston-rod F-now-rises and
opens the valve-J-to-waste. The water--is--now--discharged-from-the-lift-cylinder
and the lift descends to its lowest-position. When the lift requires-raising the
water-is-discharged-from-the-two-small-eylinders A and B-and-the reverse process
is gone through when the lift-rises-and-rests once more on the slippers.
Fig. 7-is-a-sectional-elevation-illustrating the third part of my Invention.- Fig.-8
partial side view.
In this arrangement (shown by Figs. 7 and 8)-the-peculiar feature-is-the-working
of a valve-supplying the cylinder by means of a tail piece or continuation-of-the
piston-rod-passing out of the back-end of the cylinder. The tail piece is hollow
and is provided with openings 15-4 and 3. The opening at 1 is supplied with
high-pressure water which passing-down-the tail-piece-to-the-opening 2-rushes into
the small-chamber 4 and drives the valve upwards into the position shown. The
water-for-driving-the-engine-now-enters-at-the-opening-A-passing-down-the-centre
of the piston valve-B-guins admission to the under side of the piston through the
port-C-driving the piston upward and at the same time-cutting off the connection
between the high-pressure-at-1,and-the-valve-chamber-4;-the-piston-continues to
rise until the opening 3 comes into line with the passage from the chamber 4. When
the-water which previously-held-the-valve-up is discharged-and-the valve-descends
owing to-the-unbalanced-pressure-due-to-the-difference in-area-between-the-piston
valve-and-the-small-piston at the top D. When the valve descends high pressure
water-is-admitted above-the-piston-and the eyele of operations-goes-on-us-before.
The-tail-piece is shown-double-in-the Drawing the interior piece being-intended
to-turn-round-like the plug of a cocok so as to partially--close-or-open-the-water-
ways-1,-2-and-3. A single-tube is however all that-need-be-ordinarily-used.
Having now particularly described and ascertained the nature and object of the
said Invention and in what manner the same is to be performed or carried out in
practice I hereby declare that I claim the said Invention of improvements in
hydraulic arrangements for lifting and lowering and-other-purposes substantially
as herein before set forth and described, wherein the following are is the peculiar
and important points or features
(+.) The arrangement for raising or lowering a tolerably constant load on a small
lifting ram by any given pressure of water.
(2.)-Raising-supporting-and-lowering lifte.
(3.)-The-movement of the piston-valve for admitting water to the eylinder-by
means of a tail-piece.
In-witness whereof I the said Samuel Chatwood-have-hereunto-set-my-l
-band
and seal this Twenty-eighth day of December-in the year-of-our-Lord One
thousand-eight-hundred-and-seventy-eight.
SAMUEL CHATWOOD. (L.S.)

page_text: LETTERS PATENT to Samuel Chatwood, of 120, Cannon Street, in the City of
London, in the County of Middlesex, Bank Engineer, for the Invention of
"IMPROVEMENTS IN HYDRAULIC ARRANGEMENTS FOR LIFTING AND LOWERING,
AND OTHER PURPOSES."
Sealed the 22nd October 1878, and dated the 28th June 1878.
PROVISIONAL SPECIFICATION left by the said Samuel Chatwood at the
Office of the Commissioners of Patents on the 28th June 1878.
SAMUEL CHATWOOD, of 120, Cannon Street, in the City of London, in the County
of Middlesex, Bank Engineer. "IMPROVEMENTS IN HYDRAULIC ARRANGEMENTS
FOR LIFTING AND LOWERING, AND OTHER PURPOSES."
My Invention for improvements in hydraulic arrangements for lifting and
lowering, and other purposes, consists mainly as follows:-
One of the objects aimed at by my Invention is to enable a large and tolerably
constant load on the lifting ram or cylinder to be raised or lowered when desirable,
as in the case of books, cash, and such like belonging to bankers and others.
In carrying out this part of my Invention I adopt mainly the following arrange-
ments :-
The cylinder of the lifting ram is connected by a pipe with the balancing cylinder,
the respective areas of the two being in suitable proportion. When the ram of one
cylinder is raised the ram of the other is lowered in exactly the same way as
weights on a scale beam. Supposing that the weight on the lifting ram is one ton,
then to balance it on the other cylinder a weight must be placed bearing such a
proportion to the ton weight as is represented by the direct proportion of the areas
of the cylinders. If now it is desirable to raise the ram of the lifting cylinder
(supposing it to be in its lowest position) a further weight must be applied to the
balancing cylinder ram to overcome the friction of the packings, &c., of the two
cylinders, the friction of the water passing through the connecting pipe being at
slow speed, almost nil.

page_text: The weight having been applied as above stated, and the ram of the lifting
cylinder raised, then to lower it again this extra weight that has been applied to
the balancing cylinder must be removed, and a corresponding increase of weight
must be brought to bear on the ram of the lifting cylinder in order to overcome, as
before, the friction of the apparatus. Now this extra balanced weight may virtually
be applied to the lifting cylinder by removing a corresponding weight from the
balancing cylinder, leaving the lifting cylinder untouched as regards the removal of
its weight. Suppose now that the ram of the balancing cylinder in passing out of
its gland is attached to another cylinder, this other cylinder being inverted in such
a way that it covers or partially covers the balance cylinder proper, and at the same
time the upper portion of the balance cylinder is enlarged outside, so as to form a
water-tight joint with the interior of the inverted cylinder. Now if the inverted
cylinder, which is carried by the ram of the balancing cylinder, is made very thick,
or is arranged to carry weight, its weight can be so adjusted as to always raise the
lifting cylinder ram, and if the ram of the lifting cylinder has been raised in this
manner and it is required to lower it again, then in order to remove some of the
weight from the balancing cylinder ram, water at a comparatively low pressure is
admitted into the space between the bottom of the inverted cylinder and the top of
the balancing cylinder. Now as this inverted cylinder must from its position have
an area greatly larger than the balancing ram, which 'must of course be subtracted
from it, a considerable upward pressure is oxorted by the low-pressure water intro-
duced in the inverted cylinder; this water pressing upwards, virtually removing a
portion of the weight from the balancing cylinder and causing the lifting ram to
descend, the balance having been disturbed to its advantage.
The inverted cylinder may or may not be used, according to circumstances.
If desirable, a small supplementary cylinder may be used to destroy the
unbalanced weight on the balancing cylinder, and throw the advantage on the side
of the lifting cylinder.
The second part of my Invention relates to the construction of hydraulic elevators
and automatic valve gear, and is mainly as follows:-Where an automatic lift
regulator applicable to raising and lowering is required, the arrangements consist
principally of two single-acting hydraulic cylinders provided with pistons and
suitable piston rods. On each piston rod or on an extension of the same is a
counterbalance weight to cause the piston and its connections to fall when the water
pressure is removed from beneath the pistons of the two cylinders. The high-
pressure water is supplied to the under side of the pistons by a suitable pipe, and
as one main pipe supplies both cylinders the pressure of the water causes both
pistons to rise at the same time. A pipe for drawing off any water that may lonk
through during the time the high-pressure water is acting upon the under side of
the piston is supplied. The high-pressure pipe passes on its way to the main supply
trough a three-way cock, the said cock having two ways placed in diametrically
opposite directions in the body or case of the cock, and one way at the bottom of
the body or case of the cock, in the centre line of the plug or spindle of the cock.
The high-pressure pipe is fitted to this latter opening, and as the plug of the cock
is hollow and has but ono opening in its side, communication can be made (by
turning the spindle round half a revolution) with either of the openings in the side
of the body or case of the cock. One of these openings in the side of the case of
the cock is in communication with the high-pressure main, the other with the drain
passing away. It is therefore evident that by turning the spindle of the cock
round half a revolution either way the water can be either admitted or discharged
from the cylinders as desired.
A contraction of the piston rod of the cylinder is connected in any convenient
manner with a sleeve or hollow piston valve, which is so arranged as to open in the
middle position to supply, and in the extreme up and down positions to waste, so
that according to the position of the valve the left cylinder is either supplied with
high-pressure water, or the high-pressure water is discharged from it. By suitable
mechanism the cylinder is connected with the lift. The lift, when raised, rests upon

page_text: supporting bolts or slippers sliding in suitable bracket, these slippers, together with
the sleeve valve, being worked by the cylinders before described.
The extension of the piston rod of one of the cylinders passes through a peculiarly
formed slot in the back end of the slipper, the piston rod at this point carrying a
button or collar so arranged that when the slipper is fully out the rod can pass
right upwards clear of the slipper; but when the slipper is in the button, and
therefore the piston rod cannot pass right up through the slipper, but is held about
midway in its stroke, or in such a position that the sleeve valve is open to supply
the lift cylinder with high-pressure water. When the valve is in this position the
lift is rising, and continues to rise until a fixed pin in the lift comes in contact with
the end of a releasing catch; when this catch is raised sufficiently high the
supporting bolts or slippers are shot out by one of the cylinders, and as soon as
they are fully shot out the button on the piston rod is released from its slot, and
the rod being left free the cylinder draws it upwards, opening the sleeve valve to
waste, and letting the lift down again to rest upon the slippers or bolts. On
exhausting the water from the cylinders the lift is first raised to take the weight
off the bolts or slippers, which are then withdrawn, and the lift descends to its first
position.
The third part of my Invention relates to an improved hydraulic engine for
automatically keeping up the accumulators of hydraulic elevators, lifts, or cranes,
and is mainly as follows:-The engine is constructed with cylinder and piston, and
tail piece working with the piston through a stuffing box, the piston valve having a
reduced piston.
The engine may be single-acting and in combination with a pump, but it may
also be made double-acting, and entirely independent of any other contrivance. It
acts as follows:-The water entering at the pump, suction is supposed to come in
with sufficient pressure to drive the engine piston downwards. Now when the
piston has travelled a certain distance down an opening in the tail piece will come
opposite an opening in the cylinder, and another opening comes opposite a corre-
sponding opening in the same.
The last-mentioned opening or a branch is supplied with high-pressure water,
which enters at one of the openings when in position before described, and passes
along to the under side of the piston of the valve, raising it until the space left is
opposite a port in the cylinder. The high-pressure water for driving the cylinder
now rushes in and raises the piston, when an opening in the tail piece comes into
such a position that the water contained in the end of the valve box is discharged
down through the hollow tail piece. The piston is brought back by the pump inlet,
and the cycle of operations goes on as before.
It should be noted that the openings in the tail piece are made adjustable to suit
various speeds.
This part of my Invention may also be used for other purposes where hydraulic
power is available.

page_text: '
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Samuel Chatwood in the Great Seal Patent Office on the 28th
December 1878.
SAMUEL CHATWOOD, of 120, Cannon Street, in the City of London, in the County
of Middlesex, Bank Engineer. 'IMPROVEMENTS IN HYDRAULIC ARRANGEMENTS
FOR LIFTING AND LOWERING, AND OTHER PURPOSES."
My Invention for improvements in hydraulic arrangements for lifting and
lowering, and other purposes, consists substantially as follows:-
One of the objects aimed at by my Invention is to enable a large and tolerably
constant load on the lifting ram or cylinder to be raised or lowered when desirable,
as in the case of books, cash, and such like belonging to bankers and others.
In carrying out this part of my Invention I adopt the following arrange-
ments :-
The cylinder of the lifting ram is connected by a pipe with the balancing
cylinder, the respective areas of the two being in suitable proportion. When the
ram of one cylinder is raised, the ram of the other is lowered in exactly the same
way as weights on a scale beam. Supposing that the weight on the lifting ram is
one ton, then to balance it on the other cylinder a weight must be placed bearing.
such a proportion to the ton weight as is represented by the direct proportion of
the areas of the cylinders. If now it is desirable to raise the ram of the lifting
cylinder (supposing it to be in its lowest position) a further weight must be applied
to the balancing cylinder ram, to overcome the friction of the packings, &c., of the
two cylinders, the friction of the water passing through the connecting pipe being
at slow speed, almost nil.
The weight having been applied as above stated, and the ram of the lifting
cylinder raised, then to lower it again, this extra weight that has been applied to
the balancing cylinder must be removed, and a corresponding increase of weight
must be brought to bear on the ram of the lifting cylinder, in order to overcome as
before the friction of the apparatus.
Now this extra balancing weight may
virtually be applied to the lifting cylinder by removing a corresponding weight
from the balancing cylinder, leaving the lifting cylinder untouched as regards the
removal of its weight. Suppose now that the ram of the balancing cylinder in
passing out of its gland is attached to another cylinder, this other cylinder being
inverted in such a way that it covers, or partially covers, the balance cylinder
proper, and at the same time the upper portion of the balance cylinder is enlarged
outside, so as to form a water-tight joint with the interior of the inverted cylinder.
Now if the inverted cylinder which is carried by the ram of the balancing
cylinder is made very thick, or is arranged to carry weight, its weight can be so
adjusted as to always raise the lifting cylinder ram, and if the ram of the
lifting cylinder has been raised in this manner, and it is required to lower it
again, then, in order to remove some of the weight from the balancing cylinder
ram, water at a comparatively low pressure is admitted into the space between the
bottom of the inverted cylinder and the top of the balancing cylinder. Now as
this inverted cylinder inust from its position have an area greatly larger than that
of the balancing ram, which area must of course be subtracted from it, a consi-
derable upward pressure is exerted by the low-pressure water introduced in the
inverted cylinder; this water pressing upwards, virtually removing a portion of the
weight from the balancing cylinder ram and causing the lifting ram to descend, the
balance having been disturbed to its advantage.
The inverted cylinder may or may not be used, according to circumstances.
If desirable, a small supplementary cylinder may be used to destroy the un-
balanced weight on the balancing cylinder, and throw the advantage on the side of
the lifting cylinder.
The second part of my Invention relates to the construction of hydraulic

page_text: -Where an
elevators and automatic valve gear, and is effectuated as follows:-
automatic lift regulator applicable to raising and lowering is required, the arrange-
ments consist principally of two single-acting bydraulic cylinders provided with
pistons and suitable piston rods. On each piston rod, or on an extension of the
same, is a counterbalance weight, to cause the piston and its connections to fall
when the water pressure is removed from beneath the pistons of the two cylinders.
The high-pressure water is supplied to the under side of the pistons by a suitable
pipe; and as one main pipe supplies both cylinders, the pressure of the water causes
both pistons to rise at the same time. A pipe for draining off any water that may
leak through during the time the high-pressure water is acting upon the under side
of the piston is supplied. The high-pressure pipe passes on its way to the main
supply through a three-way cock, the said cock having two ways placed in diamet-
rically opposite directions in the body or case of the cock, and one way at the
bottom of the body or case of the cock, in the centre line of tho plug or spindle of
the cock. The plug of the cock is hollow, and has but one opening in its side, so.
that communication can be made (by turning the spindle round half a revolution)
with either of the openings in the side of the body or case of the cock. One of
these openings in the side of the case of the cock is in communication with the
high-pressure main, the other with the drain passing away. It is therefore evident
that by turning the spindle of the cock round half a revolution either way the
water can be either admitted or discharged from the cylinders as desired.
A continuation of the piston rod of the cylinder is connected in any convenient
manner with a sleeve or hollow piston valve, which is so arranged as to open in the
middle position to supply, and in the extreme up and down positions to waste, so
that according to the position of the valve the lift cylinder is either supplied with
high-pressure water or the high-pressure water is discharged from it. By suitable
mechanism the cylinder is connected with the lift. The lift when raised rests upon
supporting bolts or slippers sliding in suitable bracket, these slippers together
with the sleeve valve being worked by the cylinders before described.
The extension of the piston rod of one of the cylinders passes through a peculiarly
formed slot in the back end of one of the slippers, the piston rod at this point
carrying a button or collar so arranged that when the slipper is fully out the rod
can pass right upwards clear of the slipper, but when the slipper is in the button,
and therefore the piston rod cannot pass right up through the slipper, but is held
about midway in its stroke, or in such a position that the sleeve valve is open to
supply the lift cylinder with high-pressure water. When the valve is in this
position the lift is rising and continues to rise until a fixed pin in the lift comes in
contact with the end of a releasing catch. When this catch is raised sufficiently
high the supporting bolts or slippers are shot out by one of the cylinders, and as
soon as they are fully shot out the button on the piston rod is released from its slot,
and the rod being left free the cylinder draws it upwards opening the sleevo
valve to waste, and letting the lift down again to rest upon the slippers or bolts.
On exhausting the water from the cylinders the lift is first raised to take the
weight off the bolts or slippers which are then withdrawn, and the lift descends to
its first position.
The third part of my Invention relates to an improved hydraulic engine for
automatically keoping up the accumulators of hydraulic elevators, lifts, or cranes,
and is effectuated as follows:-The engine is constructed with cylinder and piston,
and tail piece working with the piston through a stuffing box, the piston valve
having a reduced piston.
The engine may be single acting and in combination with a pump, but it may
also be made double acting and entirely independent of any other contrivance. It
acts as follows:-The water entering at the pump suction is supposed to come in
with sufficient pressure to drive the engine piston downwards. Now when the
piston has travelled a certain distance down the cylinder, an opening in the tail
piece will come opposite an opening in the stuffing box, and another opening in the
tail piece comes opposite a corresponding opening in the stuffing box.

page_text: The last-mentioned opening or a branch in connection is supplied with high-
pressure water which enters at one of these openings when in position before
described, and passes along to the under side of the piston valve, raising it until
the space left is opposite a port in the cylinder. The high-pressure water for
driving the cylinder now rushes in and raises the piston, when an opening in the
tail piece comes into such a position that the water confined in the end of the
valve box is discharged down through the hollow tail piece. The piston is brought
back by the pump inlet, and the cycle of operations goes on as before.
It should be noted that the openings in the tail piece are made adjustable to suit
various speeds.
TIL
1
"
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is sectional elevation of balancing cylinder arrangements; Fig. 2, plan of
Fig. 1; Fig. 3, sectional elevation of modified form of double cylinder.
A is the ram of the lift B, the cylinder being shown inverted after the mannor
described by me in the Specification of my Patent, No. 3626, A.D. 1875. This
cylinder is connected to the balancing cylinder by a pipe C of suitable size
and strength. The pipe is shown to enter the balancing cylinder D at the
bottom.
As will be seen this cylinder is also provided with a ram or plunger E which
works water-tight through its collar or stuffing box F at the top of the cylinder.
The top of this ram or plunger carries the outer cylinder G with its weights H.
The whole, that is, the interior ram, together with the outer cylinder and its weights,
rise at the same time. The outer cylinder G is connected with the towns or other
available pressure of water by the supply pipe I.
The action of the apparatus is as follows:-Suppose the lift or other contrivance
at B to weigh any given weight, say one ton, and it is considered desirablo, or it
may be considered necessary to raise it or lower it on a small ram as at A, tho
pressure available, whether from the street main or otherwise, being of comparatively
low pressure, the cylinder and pipe joining them are first filled with the requisite
amount of water or other desirable fluid, one of the rams being right home or at its
lowest position, the other being right out or at its highest position, as shown in the
Drawing. Supposing the lift raised, weights are now applied to the exterior
cylinder G to balance the weight of the lift B.
These weights will of course require to have a proportion directly in accordance
with the areas of the two rams A and E. If any force is now applied to either the
lift or the balancing apparatus the balance will be destroyed; supposing the force
sufficient to overcome the friction of the collars, &c., the lift will move up or down,
according to the direction in which the force is applied. Suppose now that a
further weight is applied on the exterior cylinder G sufficient to raise the lift and
anything it may contain, then to lower it again the available water pressure is
admitted through the pipe, and acting upon the under side of the exterior cylinder
cover raises the cylinder with its weights, and at the same time lowers the lift and
its contents. The proportion of the exterior cylinder area will, of course, require to
be varied according to the intensity of the available pressure of water.
Another method of carrying out the balancing is as follows (see Fig. 3):-A is
the balancing cylinder; B is the weight or motive-power cylinder. The balancing
cylinder A is connected, as before, by the pipe Ċ to the lift to be raised. The
pipe D is always open to the available water pressure, and constitutes in this case
the weighted cylinder previously described in the last arrangement. The pressure
upon the piston E is therefore sufficient always to raise the lift with its load.
When it is required to lower the lift the available pressure is admitted on the other
side of the piston E, and the lifting pressure reduced in sufficient proportion to
allow the lift to descend,

page_text: Fig. 4, sectional elevation, illustrating the second part of my Invention; Fig. 5,
side view; and Fig. 6, plan of one of the slippers, showing slot in same..
A and B are the two single-acting cylinders, provided with pistons and rods C
and D, E and F. To these rods are attached weights G and H, equal, or nearly so,
to half the lifting power of the pistons. The piston rods are continuod down past
the weights, and one, the rod of the cylinder B, is connected to a piston or equi-
librium valve J, so constructed that it is open to exhaust at its highest and lowest
positions respectively, and open to supply at its mid-position. On the piston rod F
is a disc or button K securely fastened thereon. The piston rod D of the cylin-
der A is connected by a lever and weight shaft, as shown, with the slippers or
bolts L and M. These bolts shoot out when the lift is at the right height, and the
lift rests upon them during such time as it may be required raised. O is a pin in
the lift, which as the lift rises engages with the lever N, and lifts the holding pin P
out of the bolt L, allowing the weight G to descend and shoot out the bolts.
The arrangements act as follows:-If it is required to lower the lift after it has
been raised and is resting on the bolts L, M, the high-pressure water is admitted
to the under side of the two pistons E and C. The piston C cannot rise because
the weight of the lift keeps the bolts M & L from moving, but the piston E rises
until the button K comes against the under side of the grooved slot K' in the
slipper L. This raises at the same time the piston of the valve J to supply. High-
pressure water is admitted by this valve to the lift cylinder, and the lift is raised.
As soon however as the weight is removed from the bolts the piston C commences to
rise and draws them back until the enlarged opening K³ in the slot of the bolt L
comes opposite the button K on the piston rod F; the piston rod F now rises and
opens the valve J to waste. The water is now discharged from the lift cylinder,
and the lift descends to its lowest position. When the lift requires raising the
water is discharged from the two small cylinders A and B, and the reverse process
is gono through, when the lift rises and rests once more on the slippers.
Fig. 7 is a sectional clevation illustrating the third part of my Invention; Fig. 8,
partial side view.
In this arrangement (shown in Figs. 7 and 8) the peculiar feature is the working
of a valve supplying the cylinder by means of a tail piece or continuation of the
piston rod passing out of the back end of the cylinder. The tail piece is hollow,
and is provided with openings 1, 2, and 3. The opening at 1 is supplied with
high-pressure water, which passing down the tail piece to the opening 2 rushes into
the small chamber 4, and drives the valve upwards into the position shown. The
water for driving the engine now enters at the opening A, passing down the centre
of the piston valve B gains admission to the under side of the piston through the
port C, driving the piston upward, and at the same time cutting off the connection
between the high pressure at 1 and the valve chainber 4, the piston continues to
rise until the opening 3 comes into line with the passage from the chamber 4, when
the water which previously held the valve up is discharged, and the valve descends,
owing to the unbalanced pressure due to the difference in area between the piston
valve and the small piston at the top D. When the valve descends high-pressure
water is admitted above the piston, and the cycle of operations goes on as before.
The tail piece is shown double in the Drawing, the interior piece being intended
to turn round like the plug of a cock, so as to partially close or open the water-
ways 1, 2, and 3. A single tube is however all that need be ordinarily used.
Having now particularly described and ascertained the nature and object of the
said Invention, and in what manner the same is to be performed or carried out in
practice, I hereby declare that I claim the Invention of improvements in hydraulic
arrangements for lifting and lowering, and other purposes, wherein the following
are peculiar and important points or features:--
(1.) The arrangement for raising or lowering a tolerably constant load on a small
lifting ram by any given pressure of water.
(2.) Raising, supporting, and lowering lifts.

page_text: (3.) The movement of the piston valve for admitting water to the cylinder by
means of a tail-piece.
In witness whereof, I, the said Samuel Chatwood, have hereunto set my hand
and seal, this Twenty-eighth day of December, in the year of our Lord One
thousand eight hundred and seventy-eight.
ALETTET
CHATOOD
SAMUEL CHATWOOD. (1.5)