Improvements in or relating to Double Lifts for Loads of any kind, in particular for Building Materials in Utilising the Weight and the Tractive Power of the Workman.
Year: 1897

page_text: Improvements in or relating to Double Lifts for Loads of any kind, in
particular for Building Materials in Utilising the Weight and the
Tractive Power of the Workman.
I, WILHELM DANIEL AUGUST RIETSCH, of 48 Kreuzbergstrasse, Berlin, Prussia,
in the Empire of Germany, District Ranger, 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 an appliance for utilising the weight of the body of.
a workman or user for raising or lowering loads by means of a completely counter-
balanced double lift, where the weight of the load in one cage is approximately
compensated or balanced by the weight of the workman in the other cage. There
is moreover arranged in the double lift constructed according to my present inven-
tion a guide rope fastened above and below to the scaffold or to other fixed points
and traversing each cage so that the workman standing in one cage can raise,
lower or stop the load contained in the other cage at any moment, when in
motion, by exerting a pull on the guide rope. There are provided furthermore
in the above mentioned counterbalanced double lift having guide ropes traversing
each cage, arrangements for avoiding a too early sudden starting of the double
lift, the opened doors of one of the two cages forming a security against the sudden
starting of the double lift.
In the present double lift, as far as it is to be used for conveying building
materials, arrangements are made for lengthening or for shortening the hoisting
repe and as the case may be, also the guide rope corresponding to the height of
the building to be erected or to be pulled down.
The double lift (see Figs. 1 to 6) consists either of two counterbalanced
cages AL (see Figs. 1 to 3) carried by one or more endless hoisting ropes a led
cver upper and lower pulleys and respectively or the two cages A 1 (see Figs. 4,
5 & 6) of equal weight are suspended on a hoisting rope a passing over an upper
pulley and they are connected with each other also by one or more ropes a
having the same weight as the hoisting rope and fastened to the bottom of each
cage, so that in any position of the two cages a complete compensation of weight
takes place between the two sides of the double lift. Through each cage there is
led a guide rope fastened above and below to the scaffold or to other fixed points,
and by means of which the workman standing in one of the cages increases, by
pulling himself with his hands upwards or downwards or by holding himself
fast, the weight moving the other weighted cage in one or the other direction
by the pull exerted, in the guide rope or he counterbalances the weighted cage
and can effect thus the raising, lowering or stopping of the weighted cage.
In the Figs. 1 to 6 of the accompanying diagrammatic drawings it is clearly

page_text: illustrated in which manner the raising lowering or stopping of the load takes
place by means of the guide ropes f.
As results from the above explanation the principal condition for a double lift
constructed according to this invention, that the double lift with its unloaded
cages L and A is completely counterbalanced. The following relates to the double
lift (Figs. 1 to 3) with an upper and lower rope-pulley (c and c¹) as well as to the
double lift shown in the Figs. 4 to 6 provided only with an upper rope-pulley
and where the bottom of one cage is connected with the bottom of the other cage
by means of a rope a¹ loosely hanging down and having the same weight as the
hoisting rope a.
C
When one cage L is weighted by a weight P and the other cage A with the
workman having likewise the weight P the whole system is in equilibrium (Figs. 1
to 4). The load is thus stationary. A motion in one or the other direction does
not even take place when there is between the load of the cage L and that of the
cage A only a difference of weight, not capable of overcoming the resistance
caused by friction in the double lift. There may therefore exist also in using the
double lift between the weight of the load in one cage L and the weight of the
workman in the other cage A a difference in one or in the other sense, which
approximately is equal to the resistance caused by friction before motion begins.
The motion effecting a raising or lowering of the load having the weight P in the
cage L is produced, if the load P and the weight P of the workman in the cage A
are equal or nearly equal by increasing by p kilogrammes the weight of the work-
man for which purpose the latter exerts a corresponding pull on the guide rope f
(see Figs. 2 and 5) or the workman diminishes his proper weight by p
kilogrammes by exerting a pull on the guide rope f in such a way that his
effective proper weight is reduced (see Figs. 3 and 6). In the first case the
workman standing in the cage A pulls himself on the fixed guide rope with his
hands from below upwards increasing thereby his effective proper weight for the
force of the pull i.e. by p kilogrammes (see Figs. 2 and 5). In the second case
the workman standing in the cage A pulls himself with his hands on the fixed
guide rope from above downwards reducing thereby his effective proper weight
for the force of the pull i.e. by kilogrammes (see Figs. 3 and 6). In the first
case, owing to the increase of the actual weight of the workman for his tractive
force of kilogrammes the load P is raised (Figs. 2 and 5) and in the second
case owing to the reduction of the actual weight of the workman for his tractive
force of kilogrammes the load P is lowered (Figs. 3 and 6).
When the load has reached its destination and the workman wishes to stop it
he need only hold fast on the guide rope in such a manner that the motion of the
load is stopped (see Figs. 1 and 4). It is of great importance that the workman
shall be able to stop the cage L with its load, while the latter is rising or
descending by a corresponding pull or to move it even in the contrary direction.
It results therefrom that the guide rope f can be used not only for raising and
lowering the load but also for stopping and breaking the load contained in the
cage L.
It has been mentioned above that in place of one hoisting rope a and lower
rope a more ropes may be used so that each cage is suspended on more than one
rope. Likewise in place of one guide rope f more guide ropes may be employed.
Instead of ropes, chains may also be used. The ropes are preferably of such a
strength that for the sake of safety in the case of rupture of a rope a single rope
(boisting rope or guide-rope) will be sufficient to sustain the weight.
For the sake of safety a device is arranged on the double lift stopping the
latter automatically and indicating at once when the load of the cage to be raised
is too light, or when the load of the cage carrying the workman and descending
from above downwards is too heavy so that the cage would descend too rapidly.
This device consists in doors arranged on the cages and opening outwards. For 5
when the doors are opened they bear at the top against the floor or in new
buildings against the beams of the floor while below the opened doors bears

page_text: underneath a beam arranged for this purpose on each side of the scaffold. The
lift is therefore stopped automatically as soon as the workman leaves the lowered
cage or as soon as the load is withdrawn from the raised cage hecaves for the tire
purposes it is necessary to open the doors and for stopping the lift it is sufficient
when the door of only one cage is opened. If the upper edge is charged with too
heavy a load, its doors will be pressed with their lower borders against the beams
of the floor so that the doors cannot be shut and the lift cannot be put in motion.
The accompanying drawings show by way of example, a double lift especially
for conveying building materials and the like provided with these arrangements
and having 2 hoisting ropes a two lower ropes a¹ and two guide ropes f. The lift
illustrated is designed particularly to be used for raising materials for new build-
ings to be erected or for lowering the materials of buildings to be pulled down,
and for this purpose it is provided with devices permitting the erection and the
pulling down of the lift quickly and easily and to increase or to reduce as desired
the hoisting height without prejudicing in any way the absolutely necessary
equilibrium.
purposes it is necessary to open the doors and for stopping the lift it is sufficient
when the door of only one cage is opened. If the upper edge is charged with too
heavy a load, its doors will be pressed with their lower borders against the beams
of the floor so that the doors cannot be shut and the lift cannot be put in motion.
The accompanying drawings show by way of example, a double lift especially
for conveying building materials and the like provided with these arrangements
and having 2 hoisting ropes a two lower ropes a¹ and two guide ropes f. The lift
illustrated is designed particularly to be used for raising materials for new build-
ings to be erected or for lowering the materials of buildings to be pulled down,
and for this purpose it is provided with devices permitting the erection and the
pulling down of the lift quickly and easily and to increase or to reduce as desired
the hoisting height without prejudicing in any way the absolutely necessary
equilibrium.
Figure 7 of the accompanying drawings is a front view of the double lift.
Figure 8 a side view thereof.
Figures 9 to 14 illustrate several details of the lift.
Figure 9 shows the manner of fastening the two hoisting ropes a to the top of
the cage one rope a being firmly connected to the cage, another Loisting rope a
being wound upon the windlass Ď.
Fig. 10 shows the hollow bottom for receiving the extension of the lower
rope n¹.
Fig. 11 represents at the left hand a plan view of the top and at the right hand
a section through the hollow bottom of the cage Fig. 10.
Fig. 12 shows the lower part of the cage with the folding door in front
elevation and the upper timber work of the building.
Fig. 13 is a plan view of the fore part of the cage with doors Fig. 12.
Fig. 14 is a front view of the upper part of a cage with door and of a part of
the cage frame.
The cages designated also by the letters L and A are suspended on the
ropes a a (or it may be wire ropes or chains) having in all their parts equal.
weight. On the underside of the cages b L and 6 A the ropes a¹ a¹ of equal weight
hang down loosely while the hoisting ropes a a are led at the top over the rotary.
pulley c. The latter is mounted upon the capping cross beam of the building
upon the trestles B which can be easily taken up and fastened to the timber work
of the buildings (Fig. 7). Both of the cages 6 L and A slide in guides d d
(Fig. 7 and 8) secured above to the timber work of the buildings and below to the
platform arranged to support the cages. With these guides d there are con-
nected by means of struts made preferably of iron at a suitable height above the
platform on the ground and above the first floor I, supports against which the
doors h h of the cages b L and b A bear when they are below and opened. In
the upper floor or beam and the lower support two pins e are arranged (see.
Figs. 7, 8, 12 & 13) against which the doors strike on shutting them as long as
the cages have not been somewhat raised or lowered.
To enable the workman to control completely in any position of the lift the
movements of the cages two vertical fixed guide ropes f are arranged which
pass through each cage and which the workman after having entered the cage
holds in his hands. In the accompanying drawings the guide rope f is shown
fastened at the top at f1 (Figs. 7 and 8) to the upper capping cross beam of the
repe pulley c and at the bottom at f2 in the ground or to the platform C.
The lift is operated by means of this guide rope f in the following manner.
First the cage L being say at the bottom is charged with a load corresponding
approximately to the average weight of the body of a workman. After this has
been done a workman who in the mean time has ascended or who is already above
enters the upper cage 6 A. The lift remains stationary as long as the doors h
1

page_text: of only one cage remain opened so that the lift cannot start against the will of
the workman. When the doors are shut the upper cage will be lowered at
once by the weight of the body of the workman provided the latter is sufficiently
greater than the weight of the load to be raised and to overcome the friction
and the lower cage will be raised. One of the guide ropes f f passing through
the cage serves in this case as a brake the workman reducing by slightly pulling
the guide rope from downward the pressure of the weight of his body against
the bottom of the cage A controlling thus the speed of the upward movement
of the cage containing the load; moreover it is at the discretion of the workman
to stop the cage at any place and at any moment or to reverse the movement of
the cage. If on the contrary the load is heavier than the weight of the workman
it is only necessary to exert on the guide rope f a slight pull from below upward
for increasing thereby the pressure of the body of the workman against the bottom
of the cage and to thus put the cages in motion and to give the latter any desired
speed; in this case also the workman can stop the cages by means of the guide
rope fat any moment or reverse the movement of the cage. It results therefrom
that the power of the workman over the movement of the double lift is the greater
and the force to be applied the less the more the weight of the load to be wound up
approaches that of the weight of the workman.
When the workman has arrived below, and the load above, it is stopped auto-
matically by the workman opening the doors hand leaving the cage. The leaves
of the doors are then pressed against the I-support extending across and above the
opened door; they cannot therefore be shut from without as long as the load has
not been withdrawn from the upper cage. But as it may happen, that under
certain circumstances force may be applied for shutting the doors, pins are pro-
vided for preventing the shutting of the door when the lower cage is unweighted
and the upper one is weighted. The door can be turned then only to such an
extent until the frame of the door strikes eitner at the bottom or at the top against
the pine (Fig. 7).
After the raised cage has been emptied, the door can easily be shut from
without, because there is no force pressing the empty cage against the upper
cross-beam. The arrangement of these doors with the striking pins e is
therefore very essential for the security and safety of the lift (see Figs. 7, 8, 12,
13 and 14).
The devices permitting the lift to be used for several heights according as the
height of the building to be erected progresses, consist essentially of a windlass D
arranged in or upon the cage as shown in Fig. 9 and Fig. 11 at the left hand,
ond of the double bottom, see Fig. 10 and Fig. 11 at the right hand. For different
hoisting heights ropes of different length are required, and, for counter-
balancing them, also lower ropes a¹ of different length. The hoisting
serving to increase the hoisting height is wound upon
windlass D of one cage, while the corresponding lower rope al lies in the double
bottom E of the other cage. When the hoisting height is increased, say to the
extent of a story, a corresponding length of the rope is wound off from the
windlass D, so that, when the cage 6 L is below, the other cage b A is above.
rope a
L
The lower rope necessary for compensation is taken out of the double bottom
and of the same length as has been wound off from the windlass D. The length
of this lower rope is fixed by clamps F (Fig. 11).
It may happen that when the cage containing the reserve lower rope has been
raised, this reserve lower rope may be drawn out of the double bottom by the
weight of the lower rope hanging down, whereby the equilibrium would be
destroyed. To avoid this, the clamp F is provided. If the hoisting height is to
be altered, the clamp F is loosened, and after the necessary length of lower-rope
has been drawn out the rope is secured again in the clamp. If two hoisting
rcpes a a arranged one parallel to the other, and also therefore two lower
ropes a¹ a¹ are employed (which is possible in this construction of the lift) a

page_text: windlass D must be arranged upon or in each cage and each cage must be pro-
vided with a double bottom E as shown in Figs. 7 to 11 of the accompanying
drawings:
.
The double lift may be used also in the inverse manner as may be readily
5 understood from the construction above described, that is to say, when materials
are to be conveyed from above downwards; in this case the workman travels from
below upwards. The cages may of course also he- larger for taking up two or
more workmen, so that a double or multiple load must be charged. In this case
it is advisable to use, for greater safety, several strong guide ropes f f passing on
each side through each cage.
The above described double lift is in particular suitable in such cases, where
heavy loads are at present carried up by workmen, say in new buildings. This
fatiguing labour is obviated in such a manner that the unloaded workman ascends,
and raises in travelling downward in the cage the load by his weight and, perhaps
an additional slight effort. At the same time the danger to which workmen
carrying up heavy loads on ladders and scaffolds are exposed, are almost entirely
avoided. The double lift above described may be used also for other purposes.
Having now particularly describo and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what I
claim is:-
1. A double lift for loads of any kind in particular for building materials in
making use of the weight of the body and of the tractive power of one or more
workmen, consisting in the arrangement (a) of one or more endless hoisting
ropes to which are attached two counterbalanced cages, or a lower connection of
the counterbalanced cages suspended on one or more hoisting-ropes passing over
a pulley, the said lower connection being formed of one or more lower ropes having
the same weight as the hoisting rope or ropes. (b) of one or more guide ropes
aranged vertically in the hoisting shaft and passing through each cage and
secured at top and bottom to the scaffold or to other fixed points, by means of
which guide ropes the workman standing in one of the cages can increase, decrease,
or balance the weight serving to put in an unward or downward motion the other
cage carrying the load to be raised by exerting on the fixed guide rope a pull
upwards or downwards or by holding fast the said guide ropes, effecting thereby
the raising lowering or stopping of the cage supporting the load at any moment
substantially as described.
2. In a double lift of the character described the arrangement on the cages of
doors opening outwards and bearing, when opened in the raised position of the
cage against the floor or the beams of the corresponding floor, and at the lowered
position of the cage against a support connected above the door, to the framing so
that the lift is automatically stopped, when the workman leaves his cage whereby
the doors when the raised cage alone is loaded or considerably overcharged are
firmly pressed against the floor or the support, and it becomes impossible to shut
the doors striking pins (e e) being preferably arranged in the floor or in the
support substantially as described.
3. In a double lift of the character described the arrangement of windlasses in
or upon the cages for receiving the hoisting ropes necessary when the hoisting
height is increased, and of a hollow bottom E below the cages for receiving the
lower ropes necessary when the hoisting height is increased, for the purpose
of permitting the lift to be used for different hoisting heights, the rope portion
ecessary for lengthening the hoisting rope being wound off from the windlass
of one cage while the lower rope necessary for counterbalancing the lengthened
isting rope is taken out of the double bottom of the other cage and held fast in
required length by clamps fastened to the bottom of the cage substantially as
described.
4. The combination and arrangement of parts constituting the complete lift

page_text: apparatus substantially as described and lustrated in the accompanying
drawings.
BOULT & WADE,
Agents for the Applicant.