Improvements in or connected with Electrical Elevating Mechanism.
Year: 1894

page_text: Date of Application, 27th Sept., 1894
Complete Specification: Left, 10th May, 1895-Accepted, 22nd June, 1895
PROVISIONAL SPECIFICATION.
Improvements in or connected with Electrical Elevating Mechanism.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields, in the County of London,
Patent Agent do hereby declare the nature of this invention (which has been
been communicated to me from abroad by the "Eisenwerk late Nagel & Kaemp,
Actien Gesellschaft" of Uhlenhorst, Hamburg in the German Empire, a Joint
Stock Company entered under this style under the law of Germany) to be as
follows::-
In elevators, or cranes, operated by electricity the current should not be sent
into the armature before the brake is released, for if the full current were allowed
to flow through the armature while the latter is at rest, burning of the armature
would probably result.
Assuming that a load being already in a state of suspension, is to be still further
raised, and that an ordinary brake, adapted for foot operation, is employed for
checking the crane or elevator, either of the two following contingencies will have
to be confronted.
If the brako be released before the current is sent into the armature, the load
would be caused to first re-descend some distance, before being again started in
the upward direction, which it is, of course, desirable to avoid. If the current be
closed before the brake is taken off, the arinature would most probably be burnt
througb.
The object of this invention is to provide means whereby the armature receives
current at the precise moment that the brake is released, and without the possibility
either of the armature being burnt, of the friction being considerably increased,
or of the operation of the brake becoming uneven, or jerky, as is apt to be the
case in elevator mechanism of this class as hitherto constructed.
This invention consists in providing the reversing device with a very wide
zero section for the contact brush lever, and in positively coupling the latter to a
releasing brake, which may be of any suitable construction.
The following description of the several positions, which the said lever is
capable of assuming, will serve to illustrate the operation of the combined
mechanism.
When tlie brush lever is on the said zero section, that is to say, on that part of
the contact surface through which no current is allowed to pass to the armature,
the weight with which the releasing-brake lever is weighted, works freely, and
consequently retains in position the brake disc together with the shaft carrying
the drum and the load to be raised.
When the brush-lever is so shifted as to place the brushes upon contact-sections
adapted to send the current, through the armature in such a direction, that the
load is raised, the band of the releasing bruke will be stretched by the weight
combined with the brake lever,, and caused to firmly lock the brake-disc in position,
whilst the drum-shaft is allowed to freely revolve within the said locked brake-disc
and to raise the load.
Supposing the brush-lever moved away from the said contact sections beyond
its menn position on the zero section, but still within the latter, in this position
the armature remains unprovided with current, but the weight combined with the
t
:
14

page_text: releasing brake lever is raised and consequently the brake band is loosened, which
has the effect of allowing the brake disc to revolve backwards together with the
drum under the pull of the load, the latter being thus permitted to descend.
The position to be given to the brush-lever for lowering the hook, after the
load is removed, results from the following consideration. The unloaded hook is
not capable of running down by its own weight when the brake is released, but
the drum must be caused to revolve backwards so as to unwind the load carrying
rope chain or cable. To obtain this, current has to be caused to circulate through
the armature in a direction opposite to that for raising the load, and this is cffected
by moving the brush lever backwards beyond the zero section on contact sections
so arranged on the other side as to cause the current to traverse the armature in
the reverse direction. In this position of the brush lever the weight, combined
with the releasing brake, is raised to the full extent, and therefore the book is
allowed to rapidly descend.
The advantages accruing from the improved combination herein described may
be stated as follows:-
:-
"
Should it happen that, while a load is being raised, the supply of current, is
suddenly cut off in consequence of a breakage of the cable, or from any other
cause, the load' cannot fall, owing to the fact that during the lifting process, the
brake-band is maintained in a state of tension.
Should the operative inadvertently let go the brush lever during the descent of
a load, the weight combined with the brake-lever will instantly drop down, thereby
setting the brake in operation and arresting the load...
It is obvious that a cord pulley may be employed instead of the described brush
lever, where it is desired that the elevator may be operated, and checked from any
given distance.
Dated the 27th day of September 1894.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, W.C., Agents.
:
COMPLETE SPECIFICATION.,
Improvements in or connected with Electrical Elevating Mechanism,
1, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields, in the County of London,
Patent Agent, do hereby declare the nature of this invention (which has been
communicated to me from abroad by the "Eisenwerk late Nagel & Kaemp,
Actien Gesellschaft" of Uhlenhorst, Hamburg in the German. Empire, a Joint
Stock Company entered under this style under the Law of Germany), and in what
mapper the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
In elevators or cranes operated by electricity the current should in no case be
sent into the armature before the brake is released, for if the full current were
allowed to flow through the armature while the latter is at rest, burning the
armature would probably result.
Now assuming that a load being already in a state of suspension, is to be still
further raised, and that an ordinary brake, adapted for foot operation, is employed
for checking the crane or elevator, either of the two following contingencies will
have to be confronted.
.
If the brake be released before the current is sent into the armature, the load
would be caused to first redescend a certain distance, before being again started in
the upward direction, which it is, of course, desirable to avoid. And should the
circuit be closed before the brake is taken off, the armature, as before stated; would
be most probably burnt through.

page_text: The object of this invention is to provide means whereby the armature receives
current at the precise moment that the brake.is.released, and without the possibility
either of the armature boing burnt, of the friction being considerably increased; or
of the operation of the brake becoming uneven or jerky, as is apt to be the case in
elevator-mechanisms of this class as constructed hitherto.
T.
11
1 22.
The invention consists in providing the reversing device with a very wide zero
section for the contact brush lever, and in positively coupling the latter to a
releasing brake which may be of any suitable construction,
The following description of the several positions, which the said lever is
capable of assuming, will serve to illustrate the operation of the combined
mechanism.
When the brush lever is, on the said zero section, that is to say on that part of
the contact surface through which no current is allowed to pass to the armaturo,
the weight with which the releasing-brake lever is weighted, works freely, and
consequently retains in position the brake disc together with the shaft carrying the
drum and the load to be raised.,
When the brush-lever is so shifted as to place the brushes upon contact sections
adapted to send, the current through the armature, in such a direction, that the
load is raised, the band of the releasing brake will be stretched by the weight
combined with the brake-lever, and caused to firmly lock the brake-disc in position,
whilst the drum-shaft is allowed to freely revolve within the said locked brake-
disc and to raise the load.
ม
"
Supposing the brush-lever moved, away from said contact sections beyond its
mean position on the zero section, but still within the latter; in this position the
armature remains unprovided with current, but the weight combined with
the. releasing brake lever is raised, and consequently the brake band, loosened,
which has the effect of allowing the brake-disc to revolve backwards together
with the drum under the pull of the load, the latter being thus permitted to
descend.
1.
The position to be given to the brush lever for lowering the hook, after the
load is removed, results from the following contemplation:-The unloaded hook
is not capable of running down by its own weight when the brake is released, but
the drum must be caused to revolve backwards so as to unwind the load carrying
rope or cable. To obtain this, current has to be caused to circulate through the
armature in a direction opposite to that for raising the load, and this is brought
about by moving the brush lever backwards beyond the zero section on contact
sections so arranged on the other side as to cause the current to traverse the
armature in the reverse direction. In this position of the brush lever the weight
combined with the releasing brake is raised to the full extent, and therefore the
hook allowed to rapidly sink
1f
The advantages accruing from the improved combination herein described' may
be stated as follows:
11.7
of
Should it happen that, while a load is being raised, the supply o qurrent 18
suddenly cut off in consequence of a breakage of the cable or from any other cause,
the load cannot fall, owing to the fact that during the lifting process, the brake-band
is maintained in a state of, tension.
12/
Should the operative inadvertently let go the brush lever during the descent of
load, the weight combined with the brake-lever will instantly drop down, thereby
setting the brake in operation and arresting the load.
171
It is obvious that a coro-pulley may be employed instead of the described brush
lever, where it is desired that the elevator may be operated, and checked from
any given distance.
314
And in order to enable the present invention to be fully understood. I have
represented on the annexed sheet of drawings an electrical elevating
"
defice T
served
by a releasing, brake provided with the described improvement, the co-operating
parts of the same being shewn in four different positions viz.
20
.

page_text: position or parts for raising the load;
Fig. 3 position of parts for allowing the load to descend';
:
Fig. 4 position of parts for causing the unloaded hook to run down.
Identical parts are indicated by similar letters.
A is the rope-drum which is rotatably supported with journals a in the frame a¹,
and on which is loosely mounted the brake disc A' provided with the teeth A³, whilst
the driver a* engaging with the latter, is pivotally fixed to the drum. D is the
dynamo for driving the drum, and E the rope connected with the latter and carrying
the hook for the load, this hook being not shewn on the drawings.
B is the brake-band surrounding the periphery of the disc A' and fixed with
both its ends to the brake-lever b, which consists in a bent lever pivotted to the
frame a at its knee. The horizontal arm of this lever carries a weight B¹ which
can be shifted thereon to lengthen or shorten the said arm, whilst to the end 6××
of the descending arm is pivotted a rod which extends to the left and is passed
with its left hand through an opening in the lower end of the reversing-lever C',
and has on the other side of said opening a projection which preferably
consists in a nut so as to enable the working length of rod to be varied.
C is the reversing device composed of the said lever C¹ pivotted at c³, the
conducting lowering sections, the broad non-conducting section c, and the
conducting raising sections c¹, all of these sections being arranged in one row on an
arc of a circle, so that the lever C' provided with a conductive portion opposite
to the said sections can be caused to slide with its conductive portion over the
said sections from the left to the right, or vice versa, as desired. According as
the lever C¹ is caused to make contact with the raising sections c¹ or the lowering
sections electric current is allowed to pass through the armature of the
dynamo D in such a direction that the drum A is caused to rotate to the right
winding up the rope, or to the left unwinding the same, whilst current is prevented
from circulating through the armature, as soon as the said lever arrives at or is
on the zero section c. The latter is sufficiently broad for allowing the current
to be cut off for some time before the reversion takes place. Moreover,
the sections and are composed each of a series of contacts so arranged
that the armature of the dynamo is gradually supplied with the full strength of
current.
.:
Supposing the load to be raised at a certain height and then the reversing lever
shifted from the position it occupies in Fig. 2 to the position shewn in Fig. 1, i.e. on
the zero section (. In this position of lever C, the drum A has no rotation
imparted to it because of the current being cut off from the dynamo, whilst the
weight Bis in so low a position that it tightens the brake-band 'B around the
disc A with such a friction as to enable the latter to withstand the pressure exerted
by the driver a* against the teeth A2 with which the former is engaged under the
pull of the load tending to turn the drum to the left. Consequently the load is
retained in its raised position.
Supposing the reversing lever shifted from the position shown in Fig. 1 back to
the loft or the position represented in Fig. 2. In being thus shifted, it successively:
passes the series of contacts e' until it arrives at the last one of the same whereby
the full strength of current is gradually supplied to the armature of the dynamo.
On the other hand, the lower end of lever in turning to the right slides ou the
rod and raises the same, whereby the weight B is allowed to descend corre-
spondingly, so that the brake band is still more tightened whilst the drum A is
permitted to be turned to the right, the driver a sliding over the teeth A
Supposing the reversing lever C¹ to be shifted from its' left hand position 'shewn
in Fig. 1, to the right but not far enough to make contact with the lowering
section c², as represented in Fig. 3. By thus shifting the lever'C' the current is
gradually cut off from the armature of the dynamo which remains without current;
whilst, on the other hand, the lower end of 'lever C, in turning to the left, comes
against the nut 6 and thereby shifts the rod to the left. This has the effect of
so turning the brake lever b that the weight B' is sufficiently lifted to cause the

page_text: friction of the brake-band B to be so reduced that the pull of the load is permitted
to turn the drum to the left by means of the driver a* engaged against one of the
teeth A. Consequently the load is permitted to descend, and it descends at a
speed corresponding to the reduced friction of the brake-band B.
After the load has been raised to the full height and removed from the hook,
the latter is caused to run down quickly by shifting the reversing lever C' from the
position it occupies in Fig. 2 to the last one of the contacts of the lowering
section as shewn in Fig. 4, whereby, on the one hand, tho current is first gradually
cut off from the dynamo which then remains without current as long as lever C¹
slides on the zero section, when it is gradually supplied again with current but
in the reverse direction, whilst, on the other hand, the rod b is so far shifted
to the left as to raise the weight B¹ to its highest position, whereby the brake-
band B is fully loosened.
Haring now particularly described and ascertained the nature of said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :
A reversing device for electrical elevating mechanisms in which the reversing
lever (C) and the brake-lever (6) of a releasing brake are coupled together by
means of a rod (1) in such a manner that shifting the reversing lever from the
retaining position (in which no current is supplied) into the raising position causes
the said lever (C¹) to slide on said rod (6) so that the brake band is maintained
in a tightened condition by the pull of the weight the brake lever (b) is weighted
with, whilst shifting the reversing lever (C) into the lowering position causes the
said lever (C) to shift the said coupling rod (6¹) so as to loosen the brake band
by lifting the said weight, substantially as described.
Dated this 10th day of May 1895.
JOHNSONS & WILLCOX,
Agents.