Improvement in Hoisting Apparatus
Year: 1891

page_text: Date of Application, 6th Aug., 1891-Accepted, 12th Sept., 1891
COMPLETE SPECIFICATION.
Improvement in Hoisting Apparatus.
1, JAMES GIBBINS, of 83 Patton Street, Springfield, Massachusetts, United
States of America, Machinist, do hereby declare the nature of my invention for
"IMPROVEMENT IN HOISTING APPARATUS," and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to clevator mechanisms and hoisting apparatus generally,
and has for its object to provide means whereby two winding drums of different
diameters can be arranged upon the same driving shaft, and in connection with the
same cable or cables, to be used interchangeably to hoist the car or other weight
attached to the cable or cables, and thus give to the driving shaft two maximum
hoisting capacities with the same power.
To this end my invention consists in the hoisting apparatus, comprising a
driving shaft having mounted thereon two winding drums of different diameters,
one of which is enclosed within the other, and the outer one of which is provided
with a transverse slot or opening to permit the passage of a cable to the inner
one, with means whereby it can be caused to revolve with the shaft or to turn
loosely thereon, as hereinafter fully described and particularly pointed out in the
claims.
Referring to the drawing, in which like letters designate like parts in the several
figures,
Figure 1 is a view partly in side elevation and partly in vertical section, of a
hoisting apparatus embodying the invention.
and carrying
Figure 2 is a cross-section taken upon line -x of Figure 1.
The letter a designates a driving shaft, supported in bearings b
fast and loose pulleys c d by which motion is transmitted thereto from any suitable
source of power, which shaft is herein shown as one example of driving shafts
generally, it being understood that so far as the present invention is concerned
it can be supported and driven in any of the various ways in which the shafts
of hoisting apparatus are now supported and driven. Upon said shaft is keyed
or otherwise secured the winding drum to receive the cable or cables
and
to co-operate with the latter to raise and lower an elevator car or other weight
in the usual manner. In adapting said drum to the work of raising and lowering
an elevator car, for example, its diameter and the power for driving it would be
calculated with reference to the greatest weight which it is designed to place
upon the car, and the rate of speed at which it is desired the car shall move.
Consequently, while the weight usually carried upon said car may fall far short
of such maximum, the power necessary for the latter must be maintained at all
times, or provision must be made for temporarily increasing the power whenever
the occasion therefor arises. Either of these plans materially increases the cost
of operating an elevator, and the latter leads to vexatious and expensive delays in
the use of the same.
With a view to obviating these objections to the use of a single winding drum,
I employ in connection therewith a second drum h of greater diameter, which
surrounds said drum and contains the transverse slot or opening to permit the
passage of the cable or cables to the latter, and provide means whereby said outer
drum can be caused to revolve in unison with the inner drum or be permitted to
remain stationary, at will. Said drum his provided with hub and arms h³ at
one end thereof, its opposite end being open to adapt it to be placed in position
about the inner drum, and it can be mounted, if desired, directly upon shaft a and
have connected therewith suitable clutch mechanism for locking it to said shaft.

page_text: I prefer, however, to provide the drum with an elongated hub and to mount
the hub of the outer drum thereon in such manner as to be capable of both a
revolving and a limited endwise movement thereon, and to provide means for
locking the peripheries of the drums together when it is desired that they shall
revolve in unison. As herein shown such locking means consist of inwardly pro-
jecting lugs at each end of the outer drum, and grooves or depressions 2 in the
rims of the inner drum to receive said lugs, said grooves or depressions being,
by preference, located in radial alignment with the arms of said inner drum, as
shown in Figure 2. Said lugs on the outer drum are thus adapted to be engaged
with and to be disengaged from the grooves or depressions in the inner drum by an
⚫end wise movement of the outer drum in opposite directions, or from the position
indicated by broken lines in Figure 1 to the position shown by full lines, and vice
•versi. To produce such slight endwise movement of the outer drum I have shown
a lever carrying a yoke which enters a peripheral groove in hub ², similar to
the ordinary clutch-lever, but any suitable means for such purpose can be employed.
The slot or opening in said outer drum is of sufficiently greater length than the
distance between the rims of the inner drum to permit the former to have the
necessary endwise movement without engaging the cable, and has its edges bevelled
as shown in Figure 2 to prevent chafing of the cable. The cable or cables y being
passed through said slot in the outer drum and secured to the inner drum in the
usual manner, and the outer drumm occupying the position indicated by broken lines
on Figure 1, said cable or cables can be wound upon and unwound from the inner
drum as readily as if the outer drum were entirely removed from the shaft, the
cable passing freely through the slot ', as indicated by broken lines in Figure 2,
and holding the outer drum against rotation. If now, the outer drum be moved
to the position shown by full lines in Figure 1, thereby interlocking its lugs h
with the grooves 2 of the inner drum, both drums will revolve in unison, and the
cable will then be wound upon and unwound from the outer drum, as shown by full
lines in Figure 2. Such change from one drum to the other can be made almost
instantly and without disturbing the cable.
.
In practice, power will be provided for raising with the inner drum the maximum
weight, as heretofore, and said drum will be used only when such maximum weiglit
is to be raised, the outer drum being used for the ordinary lesser weights. The
relative saving in power thus effected will, of course, depend upon the relative
diameters of the two drums, which can be varied as may be desired. If, for
example, the circumference of the inner drum be eight feet and that of the outer
drum be twelve feet, a gain of four feet in the movement of the weight will be
secured with each revolution of the driving shaft, and a corresponding gain in
power will be secured. Such gain in power is particularly advantageous in con-
nection with hydraulic elevators located in cities where the water consumed is
metered, as the necessity, heretofore existing, for using a quantity of water greatly
in excess of that actually required to raise the average weight carried upon the
car, is obviated, while the capacity of the elevator to raise the maximum weight
remains unchanged, such result in my device being secured by shifting to the inner
drum as described.
By providing means for interlocking the peripheries of the two drums thus
described, I secure a very strong and durable connection between the driving shaft
and the outer drum, and in a simple and inexpensive manner, but it will be under-
stood that any means for locking said outer drum to the shaft and releasing it
therefrom can be employed:
As hereinbefore stated, the cable, by passing through the slot in the drum, holds
the latter against rotation when not in use, but if desired, means for positively
holding said outer drum in such position can be employed.
It is obvious that three or more drums can be employed in a manner similar to
the two drums herein shown and described, either of which can be used for
raising and lowering the weight, but for all ordinary purposes two will be
• sufficient.

page_text: 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 :-
1. In a hoisting apparatus, the combination with a driving shaft having mounted
thercon a winding drum, of a second winding drum of greater diameter, loosely
mounted upon said shaft and surrounding said first mentioned drum, said outer
drum having therein a transverse slot or opening to permit the passage of a cable
to the inner drum, and means for locking the outer drum in a fixed relation to said
shaft, substantially as set forth.
2. In a hoisting apparatus, the combination with a driving shaft having rigidly
secured thereto a winding drum, of a winding drum of greater diameter loosely
mounted upon said shaft and surrounding said first mentioned drum, said outer
drum being provided with a transverse slot to permit the passage of a cable to the
inner drum, and means for locking said drums together to cause them to revolve in
unison and for disconnecting the same, substantially as set forth.
3. In a hoisting apparatus, a driving shaft, a winding drum rigidly secured to
said shaft, a second winding drum of greater diameter surrounding said first men-
tioned drum and provided with a transverse slot to permit the passage of a cable
to the latter, and means for locking said drums together at their peripheries and
for disconnecting the same, combined and operating substantially as described.
4. In a hoisting apparatus, the combination with a driving shaft and a winding
drum rigidly secured thereto, said drum being provided at each end thereof with a
projecting rim having therein a series of transverse grooves or recesses, a second
winding drum of greater diameter loosely mounted upon said shaft and capable
of a limited end wise movement thereon, said drum surrounding the first mentioned
drum and being provided with a transverse slot to permit the passage of a cable
to the latter and with inwardly projecting lugs at each end thereof, which are
adapted to enter the grooves or recesses in the inner drum to lock the two drums
together, and means for imparting endwise movement to said outer drum, sub-
stantially as set forth.
Dated GIS day or
LCOLTAT
JAMES GIBBINS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.