Improved Means for Controlling the Speed of Hydraulic Lifts, Cranes, and similar Appliances.
Year: 1895

page_text: Date of Application, 1st Mar., 1895
Complete Specification Left; 2nd Dec., 1895-Accepted, 25th Jan., 1896
PROVISIONAL SPECIFICATION.
Improved Means for Controlling the Speed of Hydraulic Lifts,
Cranes, and similar Appliances.
I WILLIAM ARTHUR KER, of: 2 Kingdon Road, West Hampstead, in the
County of Middlesex, Engineer, do hereby declare the nature of this invention to
be as follows:
"
This invention relates to improved means applicable for use as a governor for
controlling the speed of lifts, cranes and similar appliances; the same being
moreover capable of acting as a safety device for arresting "the movement. of the
lift or other apparatus in the event of a pipe bursting.
The principle on which the action of my improved governor depends is that on
an undue acceleration of speed taking place, and the friction of the water through
the pipes and passages becoming excessive; a substantial difference of pressure
occurs as between one part and another of the pressure system. From two such
points, pipes are led to the opposite ends of a cylinder in which a piston works;
the difference of pressure on the opposite sides of the said piston being utilized to
move a regulating valve, which restricts. or shuts off the supply of the power-water
to the lift or other operative cylinder.
}
In applying my improved: governing apparatus to a suspended lift or crane in
which a "jigger "-cylinder is,employed, the power-water is led from the inlet valve
on the main, through a valve apparatus, comprising a valve of the double cone or
other suitable type to the jigger-cylinder. The double cone valve,. which is by
preference arranged vertically, is in connection above by means of a chain passing
over pullies with a weight which tends to raise the valve.. Immediately beneath
this valve is arranged a controlling apparatus consisting of a cylinder enclosing a
piston whereof the rod projects both upwards and downwards through the top and
bottom cylinder covers respectively. The upwardly projecting portion of the
piston rod is connected with the valve stem of the valve above referred to; whilst
the downwardly projecting portion of the piston rod is connected with a' weight.
This weight serves to regulate the speed of the lift on the down journey ;"whilst
the weight previously referred to regulates the speed of the lift on the upward
journey. In both cases, the rods whereby the weights are attached are furnished
with stops, arranged in such a manner that the rods are free to move downwards
to a certain extent independently of the weights, the latter being meanwhile borne
on suitably placed supports. Attachment by means of a chain' would answer
substantially the same purpose, if the weight of the chain he negligible.
In working a lift in which the cage is directly supported upon a 'plunger, and in
connection with which an accumulator is employed, my improved governing
apparatus is applied between the accumulator-cylinder and the lift-cylinder; 'that
is to say, in a pressure system in which the same water passes backwards and
forwards between the accumulator-cylinder and the lift-cylinder, and which is
isolated from the system directly supplied from the pressure main.
In applying the invention to hydraulic machines in which the motion requires to
be controlled in one direction only, the apparatus may be of substantially the same
type, except that a single cone valve, or a slide valve, instead of a double cone
valve, would be appropriate.
In either or any case, although the length of piping between (say) the

page_text: accumulator-cylinder and the lift-cylinder may be substantially equal to that
communicating from different points in that system to the opposite ends of the
controlling cylinder, the friction of the water in the respective lengths of piping
above compared is widely different; because in the system of operative piping
cominunicating between the accumulator and the lift-cylinder the water is in
movement under certain conditions of working at high velocity-whilst in the
system of piping employed for simply communicating pressure to the controlling
cylinder, the water is comparatively quiescent, the pressures on the opposite sides
of the controlling piston corresponding closely with the pressures which occur at
the points in the pressure system at which the pipes leading to the controlling
cylinder are respectively connected.
With apparatus arranged as hereinbefore described, it will be obvious that in
the event of one of the service pipes on which the support of the lift is dependent
bursting, the first tendency would be for the lift to fall at a comparatively rapid
rate. Such a movement would however have the immediate effect of operating the
controlling valve to shut off the escape of water from the jigger-cylinder or from
the lift-cylinder, as the case may be, thereby arresting the movement of the lift or
largely diminishing its speed of fall.
Dated the 1st day of March 190K
Improved Means for Controlling the Speed of Hydraulic Lifts,
Cranes, and similar Appliances.
I, WILLIAM ARTHUR KER, of 2, Kingdon Road, West Hampstead, 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 improved means applicable for use as a governor for
controlling the speed of lifts, cranes and similar appliances; the same being
moreover capable of acting as a safety-device for arresting the movement of the
lift or other apparatus in the event of a pipe bursting.
The principle on which the action of my improved governor depends is that, on
an undue acceleration of speed taking place and the friction of the water through
the pipes and passages becoming excessive, a substantial difference of pressure
occurs as between one part and another of the pressure system. From two such
points; pipes are led to the opposite ends of a cylinder in which a piston works;
the difference of pressure on the opposite sides of the said piston being utilized to
move a regulating valve, which restricts or shuts off the supply of the power-water
to the lift or other operative cylinder.
In the accompanying drawings,
Fig. 1 is a diagrammatic view illustrating one mode of applying my invention to
an hydraulic lift, the latter being suspended by a chain and counter-balanced.
Fig. 2 is a similar view showing another mode of application in which the
lift-cage is supported upon a ram.
Fig. 3 shows the improved governor adapted for employment with hydraulic
machines which require controlling in one direction only, the valve casing being
partly broken to expose the internal fittings.
Fig. 4 is a vertical section on an enlarged scale of one form of my improved
governing or controlling apparatus detached.

page_text: Fig. 5 represents in vertical section a modified construction, the controlling
piston and valve being embodied in a single casing.
Figs. 6 and 7 are respectively a vertical section and a plan (the latter partly in
horizontal section on the line 7-7 in Fig. 6) illustrating another mode of con-
struction. In all these views, the parts are shown in their normal position.
Figs. 8 and 9 are elevations of the last mentioned arrangement showing the
regulating weights in various positions of working.
Figs. 10 and 11 are plans of the weights, and Fig. 12 is a detached view of the
cross-piece or plate employed for supporting the weights; same being more
particularly applicable for use with the constructions illustrated in Figs. 5 to 9
inclusive.
Fig. 13 is a plan of the apparatus arranged for horizontal working.
The construction and operation of my improved governing apparatus will be
more clearly understood if reference he had to Fig. 4 in supplement to the figs.
illustrating the general arrangement of the controlling mechanism.
In applying my improved governing apparatus to a suspended lift or crane in
which a "jigger "-cylinder is employed (Fig. 1), the power-water is led from the.
inlet valve A on the main A', through valve apparatus B, comprising a valve b, of
the double cone or other suitable type, to the jigger-cylinder C. The valve b,
which is by preference arranged vertically, is in connection above, by means of a
chain or chains or wire ropes cc passing over pulleys cc, with a weight or
weights D, which tends or tend to raise the valve b; the ropes cc being connected,
to the stem b' of the valve by means of the cross-piece 62. Immediately beneath
this valve, or in some cases, as hereinafter described; combined therewith, is
arranged a controlling apparatus which may consist of a cylinder E enclosing a
piston e whereof the rod e¹ projects both upward and downward through the top
and bottom cylinder-covers respectively. The upwardly projecting portion of the
piston rod is connected with, or forms part of, the valve stem 6 of the valve b,
whilst the downwardly projecting portion of the piston rod is connected with a.
weight F. This weight serves to regulate the speed on the down journey; whilst
the weight or weights D regulates or regulate the speed of the lift on the upward
journey. The rods d d whereby the weights D D are attached to the ropes c c are
each furnished with a stop d' d', arranged in such a manner that the rods d d are free
to move downwards to a certain extent independently of the weights D; the latter
being meanwhile borne on suitably placed supports d² d². The downwardly
projecting portion of the piston rod is similarly furnished with a stop f, and the
weights so formed as to permit the free passage of the piston rod; supports "f
being also provided for bearing the weight F. Attachment of the weights by
means of a chain would answer substantially the same purpose, if the weight of
the chain be negligible.
In working a lift in which the cage G is directly supported upon a plunger H,
and in connection with which an accumulator is employed, as represented in
Fig. 2, my improved governing apparatus is applied between the accumulator-
cylinder K and the lift-cylinder L; that is to say, in a pressure system A° in
which the same water passes backwards and forwards between the accumulator-
cylinder K and the lift-cylinder L, and which is isolated from the system directly
supplied from the pressure main A*.
Referring to Fig. 3, in the application of the invention to hydraulic machines in
which the motion requires to be controlled in one direction only, the apparatus may
be of substantially the same type as that previously described, except that a single
cone valve 6º, or a slide valve (not illustrated), instead of a double cone valve
(such as b), would be appropriate.
In either or any case, although the length of piping A° between (say) the
accumulator-cylinder K and the lift-cylinder L may be substantially equal to the
piping A communicating from different points in that system to the opposite ends
of the controlling cylinder E, the friction of the water in the respective lengths of
piping above compared is widely different; because in the system of operativo

page_text: -
piping A° the water is in movement-under certain conditions of working at high
velocity whilst in the system of piping A2, employed for simply communicating
pressure to the piston e of the controlling cylinder E, the water is comparatively
quiescent, the pressures on the opposite sides of the controlling piston e corre-
sponding closely with the pressures which occur at the points in the pressure
system A° at which the pipes A2 A2 leading to the controlling cylinder are
respectively connected.
It will be apparent that the valve and controlling piston may be arranged in a
single casing, and that under certain conditions, as for example where the space
available is of a restricted nature, or for other economic reasons, the construction
and arrangement of the governing or controlling device may be modified in various
ways; the piston being arranged either below or above the valve. In Figs. 5 and 6,
I have shown two arrangements of a combined valve and piston. The valve b in
Fig. 5, is of the double cone or other suitable type; while in Fig. 6 it is shown as
a piston-valve. The piston e is arranged above, and connected with, the valve b.
A rod serves the purpose of piston rod and valve stem; the upwardly projecting
portion passing through a stuffing box in the cover of the cylinder E°, while the
downwardly projecting portion passes through a stuffing box at the bottom of the
valve chamber B°. At or near the lower extremity of the downwardly projecting
portion of the rod 6x is attached a cross-piece or plate g (shown in plan in Fig. 12)
for supporting the weight F*; the latter serving as a balance. A stopf on the
rod 6x serves to support the weight Dx, which acts to control the speed on the
down journey, and, in conjunction with the weight Fx, to control the speed on
the up journey. To the plate y are secured one end of each of the ropes.cc, which
latter pass over pulleys c³ c¹, carried on studs c* c* secured to the valve-casing B°;
the opposite ends of the ropes c c being. attached to rods d* dx which are in turn
secured to the bottom weight F. Guide rods hh depending from the casing B°
maintain the balance weights in alignment and so ensure their working steadily.
On the speed of. the lift exceeding the normal (for example in descending), the
increased friction of the pressure water due to its high velocity in passing through
the piping A to the accumulator, causes a diminution of pressure at the point of
connection of the pipe A2 with the pipe A° as compared with that of the pressure-
water passing through the valve, and which by acting on the under side of the
piston e, raises it,. together with the valve b, and thereby arrests the escape of the
water from the lift cylinder. Similarly, should the speed of the lift-cage in
ascending become abnormal, the pressures in the comparative systems of piping
are reversed, with the result that the piston and valve descend and shut off or
arrest the supply of water to the lift-cylinder.
In the horizontal arrangement of the valve; shown in Fig. 13, the balance
weights (D*, FX,) would be connected with the shanks 6363, whereof one is affixed
to each end of the piston rod 6x; the connecting ropes passing over suitably
arranged pulleys, as will be readily understood.
With apparatus arranged as herein-before described, it will be obvious that in
the event of one of the service pipes on which the support of the lift is dependent
bursting, the first tendency would be for the lift to fall at a comparatively rapid
rate. Such a movement would however have the immediate effect of operating
the controlling valve to shut off the escape of water from the jigger-cylinder or
from the lift-cylinder, as the case may be, thereby arresting the movement of the
lift or largely diminishing its speed of fall.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I claim :-
1. The improved method of controlling the speed of hydraulic lifts, cranes and
similar appliances, substantially as herein described; same consisting in utilising
the difference of pressure occurring in two parts of the pressure system when the
speed becomes excessive or when a pipe bursts to operate a regulating valve
which restricts or cuts off the supply or the escape of the pressure water.

page_text: 2. The improved means for controlling the speed of hydraulic lifts, cranes and
similar appliances, substantially as herein described, and comprising a piston
operated by the difference of pressure occurring at two different points in the
pressure-system, and a valve connected with said piston, and arranged to restrict
or shut off the supply of pressure water to or its escape from the lift-cylinder.
3. For use in connection with hydraulic lifts, cranes and similar appliances, the
improved regulating or controlling apparatus arranged or operating substantially
as described with reference to Fig. 3, Fig. 4 or any equivalent construction.
Dated the 29th day of November 1895.
For the Applicant,
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Chartered Patent Agent.