Improvements in Electric Cranes.
Year: 1888

page_text: Date of Application, 16th Oct., 1888
Complete Specification Left. 16th July, 1889-Accepted, 12th Oct., 1889
PROVISIONAL SPECIFICATION.
Improvements in Electric Cranes.
I THOMAS DRAKE HOLLICK, of Shore Road, Hackney in the County of Middlesex,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to cranes actuated by electricity as a motive power.
In such cranes it is found advisable that the electric motor by which the crane
is actuated should run continuously at a high speed, and without the necessity of
varying its speed for the purpose of hoisting or slewing travelling, and adjusting the
radius of the jib of the crane, such variations of speed of the electric motor having
been heretofore sometimes effected by the use of varying resistances in the electrical
circuit of the motor, or by equivalent means.
In my invention I use, instead of such devices, frictional driving apparatus con-
sisting preferably of two flat pullies, one upon the motor shaft composed of paper
applied in the wellknown way, and that upon the driven shaft which actuates the
movements of the crane being of cast iron. Upon the latter driven shaft I arrange
the necessary clutches, brakes, and other devices, by which the same movements such
as hoisting lowering, or slowing can be effected as desired.
I arrange in a convenient position a hand lever actuating a screw, excentric, or
equivalent device in such manner that the paper driving pulley upon the motor
shaft can be pressed with greater or less force against, or altogether removed from
contact with the metal driven pulley. I connect this lever with the hoisting clutch
lever in such a manner that either of them can be moved in or out of gear inde-
pendently or simultaneously by means of a single handle.
By this means the attendant driving the crane, is enabled to vary the pressure
between the friction pulleys so that the load may be raised slowly or quickly as desired
without varying the speed of the motor, whilst he can also throw the hoisting clutch
in or out of gear without taking his hand off the lever or handle. The shaft of the
hoisting barrel is provided with a brake connected to a lever or handle, by the use
of which in combination with that first described a load can be lifted or lowered,
without varying the speed or reversing the direction of motion of the motor.
instance, the load having been lifted as high as required, the pressure between the
friction rollers is taken off, the weight of the load being at the same time taken by the
brake, and the strain being then removed from the clutch the latter can be disconnected,
and the load lowered by means of the brake.
For
In the same way the other movements of the crane, such as slewing and travelling
can also be effected without interference with the motor.
By the improved method of construction and arrangement described, the driver is
enabled (as is necessary, more especially in quick working) to effect the movements
such as hoisting and lowering as described, without having to move his hands from
the levers or from one lever to another.
1cl
aben 1000
EDWARDS & Co.,
5, Southampton Buildings, London, Agents for the Applicant.
i
COMPLETE SPECIFICATION.
Improvements in Electric Cranes.
1, THOMAS DRAKE HOLLICK, of Shore Road, Hackney, in the County of Middlesex,
5 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, (that is to say) :-
My invention relates to cranes of different kinds actuated by electricity as a motivo

page_text: In such cranes it is found advisable that the electric motor by which the crane is
actuated should run continuously at a high speed, and without the necessity of varying
its speed for the purpose of hoisting or slewing, travelling, and adjusting the radius
of the jib of the crane, such variations of speed of the electric motor having been
heretofore sometimes effected by the use of varying resistances in the electrical circuit
of the motor, or by equivalent means.
In my invention I use, instead of such devices, frictional driving apparatus con-
sisting of a flat edged driving pinion, driving by friction a corresponding pulley, the
pinion upon the motor shaft being composed of compressed paper applied in the well
known way, and that upon the driven shaft which actuates the movements of the
crane being of cast iron, or other suitable metal.
Upon the latter driven shaft I arrange the necessary clutches, brakes, and other
devices, by which the various movements such as hoisting lowering, or slewing can be
effected as desired in the usual well known way.
I arrange in a convenient position a hand lever actuating a screw, excentric, or
equivalent device, in such manner that the paper driving pulley upon the motor shaft
can be pressed with greater or less force against, or altogether removed from contact
with the metal driven pulley. For this purpose I make the bearings in which the
motor shaft, or the driven pulley, revolves, moveable for a very short distance, the
screw, excentric, or lever as described, being connected to such moveable bearing or
bearings, so that when the lever is moved, the driving pinion and the pulley are
pressed with any desired force against each other, or can be altogether withdrawn
from contact.
I connect the lever by which the pinion and friction wheel are brought into contact
as described, with the hoisting clutch lever in such a manner that either of them can
be moved in or out of gear independently or simultaneously by means of a single
-handle.
For this purpose I make the lever double, the main lever by which the hoisting
clutch is thrown in or out of gear turning upon a centre in the usual way, and having
pivotted to it near its outer end a second lever working transversely in guides. This
second lever is connected, preferably by means of a universal joint, to a rod actuating
the screw, excentric, or equivalent device, by which the friction gear is brought into
contact or separated as described. In this way if the second lever is moved transversely
the friction gear is brought in or out of gear, whilst if it is moved together with the
principal lever to which it is connected, in a direction at right angles to the first
movement, the hoisting clutch is thrown in or out of gear as described. In this way,
the person in charge can actuate both the friction" gear, and the hoisting clutch
by means of a single handle, and he can vary the pressure between the friction
pulleys so that the load may be raised slowly or quickly as desired without varying
the speed of the motor, whilst he can also throw the hoisting clutch in or out of gear
without taking his hand off the lever or handle. The shaft of the hoisting barrel is
provided with a brake connected to a lever or handle or treadle by the use of which
in combination with that first described a load can be lifted or lowered, without varying
the speed or reversing the direction of motion of the motor. For instance, the load
having been lifted as high as required, the pressure between the friction rollers
is taken off, the weight of the load being at the same time supported by means of
the brake, and the strain being then removed from the clutch the latter can be dis-
connected, and the load lowered by means of the brake.
In the same way the other movements of the crane, such as slewing and travelling
can also be effected without interference with the motor.
In the accompanying drawing, which is in illustration of my invention, figure 1 is
a side view, and figure 2 a plan, of part of a crane. A is the top bed plate of the
crane, a the motor actuated by electricity, b the friction pinion driving the wheel c,
and d, e, the toothed gear driving the hoisting barrel f, which can be put in or out
of gear by the clutch Bevelled
g.
gear driving the slewing gear of the crane in
the usual way is shewn in dotted lines at h. The motor frame turns upon a pivot l,
and i is a lever upon the screw k, by means of which the friction pinion is pressed

page_text: centre
with greater or less force against the wheel c. The clutch lever m turns upon the
and n is a lever pivotted to it at p and also actuating the lever which
has a slot through which the lever n passes. r is the brake wheel upon the shaft of
the barrel f.
By the improved method of construction and arrangement described, the driver is
enabled (as is necessary, more especially in quick working) to effect the movements
such as hoisting and lowering as described, without having to move his hands from
the levers or from one lever to another.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. In cranes actuated by Electricity, the friction gear by which the hoisting
apparatus is set in motion, in combination with a screw, excentric, or equivalent device,
actuated by a handle, by which the friction wheels are brought into contact or
separated, as desired without materially affecting the speed of the electric motor, sub-
stantially as herein described.
2. In combination with the lever and handle by which the friction wheels are
brought into contact and separated as desired, a second lever by which the hoisting
clutch is thrown in or out of gear, the two levers being connected so that either opera-
tion may be effected by the movement of the saine handle, substantially as herein
described.
Dated
1011 1
T 1
1000
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Patentee.