U.S. patent application number 10/863292 was filed with the patent office on 2005-01-13 for elevator.
Invention is credited to Aulanko, Esko, Mustalahti, Jorma.
Application Number | 20050006180 10/863292 |
Document ID | / |
Family ID | 8562740 |
Filed Date | 2005-01-13 |
United States Patent
Application |
20050006180 |
Kind Code |
A1 |
Mustalahti, Jorma ; et
al. |
January 13, 2005 |
Elevator
Abstract
Elevator, preferably an elevator without machine room. In the
elevator, a hoisting machine engages a set of hoisting ropes by
means of a traction sheave. The set of hoisting ropes comprises
hoisting ropes of substantially circular cross-section. The
hoisting ropes support a counterweight and an elevator car moving
on their respective tracks. The hoisting rope has a thickness below
8 mm and/or the diameter of the traction sheave is smaller than 320
mm. The contact angle between the hoisting rope or hoisting ropes
and the traction sheave is larger than 180.degree..
Inventors: |
Mustalahti, Jorma;
(Hyvinkaa, FI) ; Aulanko, Esko; (Kerava,
FI) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 8910
RESTON
VA
20195
US
|
Family ID: |
8562740 |
Appl. No.: |
10/863292 |
Filed: |
June 9, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10863292 |
Jun 9, 2004 |
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PCT/FI03/00012 |
Jan 9, 2003 |
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Current U.S.
Class: |
187/254 ;
187/251; 187/264 |
Current CPC
Class: |
D07B 2201/2006 20130101;
Y10T 74/18848 20150115; B66B 7/06 20130101; B66B 15/04 20130101;
D07B 1/0673 20130101; D07B 1/16 20130101; B66B 11/009 20130101;
B66B 11/008 20130101; D07B 2501/2007 20130101; B66B 11/08 20130101;
D07B 2501/2007 20130101; D07B 2201/2006 20130101 |
Class at
Publication: |
187/254 ;
187/264; 187/251 |
International
Class: |
B66B 011/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 9, 2002 |
FI |
20020043 |
Claims
1. Elevator, preferably machineroomless elevator, wherein the
thickness of hoisting ropes is below 8 mm and/or the diameter of
the traction sheave is smaller than 320 mm and wherein the overall
contact between the traction sheave and a hoisting rope exceed a
contact angle of 180.degree..
2. Elevator according to claim 1, wherein a hoisting machine
engages a set of hoisting ropes by means of a traction sheave, said
set of hoisting ropes comprising hoisting ropes of substantially
circular cross-section, and in which elevator the set of hoisting
ropes supports a counterweight and an elevator car moving on their
respective tracks, and that the substantially round hoisting rope
has a thickness below 8 mm and/or the diameter of the traction
sheave is smaller than 320 mm and that the contact angle between
the hoisting rope or hoisting ropes and the traction sheave is
larger than 180.degree..
3. Elevator according to claim 1, wherein between the traction
sheave and the hoisting ropes there is a continues contact angle of
at least 180.degree..
4. Elevator according to claim 1, wherein the contact angle on the
traction sheave consists of 2 or more parts.
5. Elevator according to claim 1, wherein the roping of the
traction sheave is implemented using ESW roping.
6. Elevator according to claim 1, wherein the roping of the
traction sheave is implemented using DW roping.
7. Elevator according to claim 1, wherein the roping of the
traction sheave is implemented using XW roping.
8. Elevator according to claim 1, wherein the elevator car and/or
the counterweight are suspended with a suspension ratio of 2:1.
9. Elevator according to claim 1, wherein the elevator car and/or
the counterweight are suspended with a suspension ratio of 1:1.
10. Elevator according to claim 1, wherein the elevator car and/or
the counterweight are suspended with a suspension ratio of 3:1.
11. Elevator according to claim 1, wherein the elevator car and/or
the counterweight are suspended with a suspension ratio of 4:1 or
even with a higher suspension ratio.
12. Elevator according to claim 1, wherein the counterweight is
suspended n:1 and the car is suspended m:1 and m is an integer at
least 1 and n is an integer greater than m.
13. Elevator according to claim 1, wherein the average of the wire
thicknesses of the steel wires of the hoisting ropes is about 0.5
mm, and that the strength of the steel wires is greater than 2000
N/mm.sup.Z.
14. Elevator according to claim 1, wherein the average of the wire
thicknesses of the steel wires of the hoisting ropes is greater
than about 0.1 mm and less than about 0.4 mm.
15. Elevator according to claim 1, wherein the average of the wire
thicknesses of the steel wires of the hoisting ropes is greater
than about 0.15 mm and less than about 0.3 mm.
16. Elevator according to claim 1, wherein it is also implemented
according to at least two of the other preceding claims.
17. Elevator according to claim 1, wherein the strength of the
steel wires of the hoisting ropes is greater than about 2300
N/mm.sup.2 and less than about 2700 N/mm .sup.Z.
18. Elevator according to claim 1, wherein the weight of the
hoisting machine of the elevator is at most about 1/5 of the weight
of the nominal load of the elevator.
19. Elevator according to any one of the preceding claims, wherein
the outer diameter of the traction sheave driven by the hoisting
machine of the elevator is at most about 250 mm.
20. Elevator according to claim 1, wherein the weight of the
hoisting machine of the elevator is at most about 100 kg.
21. Elevator according to claim 1, wherein the hoisting machine is
of gearless type.
22. Elevator according to claim 1, wherein the hoisting machine is
of geared type.
23. Elevator according to claim 1, wherein the rope of the
overspeed governor is thicker in diameter than the hoisting
ropes.
24. Elevator according to claim 1, wherein the overspeed governor
rope is of the same thicknesses in diameter as the hoisting
ropes.
25. Elevator according to claim 1, wherein the weight of the
elevator machine is at most about 1/6 of the nominal load,
preferably at most about 1/8 of the nominal load, very preferably
less than about {fraction (1/10)} of the nominal load.
26. Elevator according to claim 1, wherein the total weight of the
elevator machine and its supporting elements is at most 1/5 of the
nominal load, preferably at most about 1/8 of the nominal load.
27. Elevator according to claim 1, wherein the diameter of the
pulleys supporting the car is equal to or less than the height
dimension of a horizontal beam comprised in the structure
supporting the car.
28. Elevator as defined in claim 1, wherein the pulleys are placed
at least partially inside the beam.
29. Elevator as defined in claim 1, wherein the track of the
elevator car is in an elevator shaft.
30. Elevator as defined in claim 1, wherein at least part of the
spaces between strands and/or wires in the hoisting ropes is filled
with rubber, urethane or some other medium of substantially
non-fluid nature.
31. Elevator as defined in claim 1, wherein the hoisting ropes have
a surface part made of rubber, urethane or some other non-metallic
material.
32. Elevator according to claim 1, wherein the hoisting ropes are
uncoated.
33. Elevator as defined in claim 1, wherein the traction sheave
and/or rope pulleys are/is coated at least in their/its rope
grooves with a non-metallic material.
34. Elevator as defined in claim 1, wherein the traction sheave
and/or rope pulleys are/is made of a non-metallic material at least
in the rim part comprising the rope grooves.
35. Elevator as defined in claim 1, wherein the traction sheave is
uncoated.
36. Elevator according to claim 1, wherein the both the counter
weight and the elevator car are suspended using a diverting
pulley.
37. Elevator according to claim 1, wherein the hoisting ropes are
passed under, over or sideways past the elevator car by means of
diverting pulleys mounted on the elevator car.
38. Elevator according to claim 1, wherein at least the traction
sheave and/or the rope pulleys form together with the hoisting
ropes a material pair that allows the hoisting rope to bite into
the traction sheave and/or into the rope pulley after the coating
on the traction sheave has worn out.
39. Elevator according to claim 1, wherein the elevator comprises a
mounting base on which the hoisting machine with the traction
sheave and at least one diverting pulley are mounted, and that the
mounting base determines the relative positions of and distance
between the diverting pulley and the traction sheave.
40. Elevator according to claim 1, wherein at least the elevator
hoisting machine, traction sheave, diverting pulley and mounting
base have been fitted as a ready-made unit.
Description
[0001] The present invention relates to an elevator as defined in
the preamble of claim 1.
[0002] One of the objectives in elevator development work is to
achieve an efficient and economical utilization of building space.
In recent years, this development work has produced various
elevator solutions without machine room, among other things. Good
examples of elevators without machine room are disclosed in
specifications EP 0 631 967 (A1) and EP 0 631 968. The elevators
described in these specifications are fairly efficient in respect
of space utilization as they have made it possible to eliminate the
space required by the elevator machine room in the building without
a need to enlarge the elevator shaft. In the elevators disclosed in
these specifications, the machine is compact at least in one
direction, but in other directions it may have much larger
dimensions than a conventional elevator machine.
[0003] In these basically good elevator solutions, the space
required by the hoisting machine limits the freedom of choice in
elevator lay-out solutions. Some space is needed to provide for the
passage of the hoisting ropes. It is difficult to reduce the space
required by the elevator car itself on its track and likewise the
space required by the counterweight, at least at a reasonable cost
and without impairing elevator performance and operational quality.
In a traction sheave elevator without machine room, mounting the
hoisting machine in the elevator shaft is difficult, especially in
a solution with machine above, because the hoisting machine is a
sizeable body of considerable weight. Especially in the case of
larger loads, speeds and/or hoisting heights, the size and weight
of the machine are a problem regarding installation, even so much
so that the required machine size and weight have in practice
limited the sphere of application of the concept of elevator
without machine room or at least retarded the introduction of said
concept in larger elevators. If the size of the machine and the
traction sheave of the elevator is reduced, then a further problem
is often the question of how to ensure a sufficient grip between
the hoisting ropes and the traction sheave.
[0004] Specification WO 99/43589 discloses an elevator suspended
using flat belts in which relatively small diversion diameters on
the traction sheave and diverting pulleys are achieved. However,
the problem with this solution is the limitations regarding lay-out
solutions, the disposition of components in the elevator shaft and
the alignment of diverting pulleys. Also, the alignment of
polyurethane-coated belts having a load-bearing steel component
inside is problematic e.g. in a situation where the car is tilted.
To avoid undesirable vibrations, an elevator so implemented needs
to be rather robustly constructed at least as regards the machine
and/or the structures supporting it. The massive construction of
other parts of the elevator needed to maintain alignment between
the traction sheave and diverting pulleys also increases the weight
and cost of the elevator. In addition, installing and adjusting
such a system is a difficult task requiring great precision. In
this case, too, there is the problem of how to ensure sufficient
grip between the traction sheave and the hoisting ropes.
[0005] On the other hand, to achieve a small rope diversion
diameter, rope structures have been used in which the load-bearing
part is made of artificial fiber. Such a solution is exotic and the
ropes thus achieved are lighter than steel wire ropes, but at least
in the case of elevators designed for the commonest hoisting
heights, artificial-fiber ropes do not provide any substantial
advantage, particularly because they are remarkably expensive as
compared with steel wire ropes.
[0006] The object of the invention is to achieve at least one of
the following objectives. On the one hand, it is an aim the
invention to develop the elevator without machine room further so
as to allow more effective space utilization in the building and
elevator shaft than before. This means that the elevator must be so
constructed that it can be installed in a fairly narrow elevator
shaft if necessary. On the other hand, it is an aim of the
invention to reduce the size and/or weight of the elevator or at
least those of its machine. A third objective is to achieve an
elevator with a thin hoisting rope and/or small traction sheave in
which the hoisting rope has a good grip/contact on the traction
sheave.
[0007] The object of the invention should be achieved without
impairing the possibility of varying the basic elevator layout.
[0008] The elevator of the invention is characterized by what is
presented in the characterization part of claim 1. Other
embodiments of the invention are characterized by what is presented
in the other claims. Some inventive embodiments are also discussed
in the description section of the present application. The
inventive content of the application can also be defined
differently than in the claims presented below. The inventive
content may also consist of several separate inventions, especially
if the invention is considered in the light of explicitly expressed
or implicit subtasks or from the point of view of advantages or
categories of advantages achieved. In this case, some of the
definitions contained in the claims below may be superfluous from
the point view of separate inventive concepts. By applying the
invention, one or more of the following advantages, among others,
can be achieved:
[0009] Due to a small traction sheave, a compact elevator and
elevator machine are achieved
[0010] By using a small coated traction sheave, the weight of the
machine can easily be reduced even to about half of the weight of
the machines now generally used in elevators without machine room.
For example, in the case of elevators designed for a nominal load
below 1000 kg, this means machines weighing 100-150 kg or even
less. Via appropriate motor solutions and choices of materials, it
is even possible to achieve machines weighing less than 100 kg.
[0011] A good traction sheave grip and light components allow the
weight of the elevator car to be considerably reduced, and
correspondingly the counterweight can also be made lighter than in
current elevator solutions.
[0012] A compact machine size and thin, substantially round ropes
permit the elevator machine to be relatively freely placed in the
shaft. Thus, the elevator solution can be implemented in a fairly
wide variety of ways in the case of both elevators with machine
above and elevators with machine below.
[0013] The elevator machine can be advantageously placed between
the car and a shaft wall.
[0014] All or at least part of the weight of the elevator car and
counterweight can be carried by the elevator guide rails.
[0015] In elevators applying the invention, an arrangement of
centric suspension of the elevator car and counterweight can
readily be achieved, thereby reducing the lateral supporting forces
applied to the guide rails.
[0016] Applying the invention allows effective utilization of the
cross-sectional area of the shaft.
[0017] The invention reduces the installation time and total
installation costs of the elevator.
[0018] The elevator is economical to manufacture and install
because many of its components are smaller and lighter than those
used before.
[0019] The speed governor rope and the hoisting rope are usually
different in respect of their properties and they can be easily
distinguished from each other during installation if the speed
governor rope is thicker than the hoisting ropes; on the other
hand, the speed governor rope and the hoisting ropes may also be of
identical structure, which will reduce ambiguities regarding these
matters in elevator delivery logistics and installation.
[0020] The light, thin ropes are easy to handle, allowing
considerably faster installation.
[0021] E.g. in elevators for a nominal load below 1000 kg and a
speed below 2 m/s, the thin and strong steel wire ropes of the
invention have a diameter of the order of only 3-5 mm.
[0022] With rope, diameters of about 6 mm or 8 mm, fairly large and
fast elevators according to the invention can be achieved.
[0023] The traction sheave and the rope pulleys are small and light
as compared with those used in conventional elevators.
[0024] The small traction sheave allows the use of smaller
operating brakes.
[0025] The small traction sheave reduces the torque requirement,
thus allowing the use of a smaller motor with smaller operating
brakes.
[0026] Because of the smaller traction sheave, a higher rotational
speed is needed to achieve a given car speed, which means that the
same motor output power can be reached by a smaller motor.
[0027] Either coated or uncoated ropes can be used.
[0028] It is possible to implement the traction sheave and the rope
pulleys in such a way that, after the coating on the pulley has
been worn out, the rope will bite firmly on the pulley and thus a
sufficient grip between rope and pulley in this emergency is
maintained.
[0029] The use of a small traction sheave makes it possible to use
a smaller elevator drive motor, which means a reduction in drive
motor acquisition/manufacturing costs.
[0030] The invention can be applied in gearless and geared elevator
motor solutions.
[0031] Although the invention is primarily intended for use in
elevators without machine room, it can also be applied in elevators
with machine room.
[0032] In the invention a better grip and a better contact between
the hoisting ropes and the traction sheave are achieved by
increasing the contact angle between them.
[0033] Due to the improved grip, the size and weight of the car and
counterweight can be reduced.
[0034] The space saving potential of the elevator of the invention
is increased.
[0035] The weight of elevator car in relation to the weight of the
counterweight can be reduced.
[0036] The acceleration power required by the elevator is reduced
and the torque required is also reduced.
[0037] The elevator of the invention can be implemented using a
lighter and smaller machine and/or motor.
[0038] As a result of using a lighter and smaller elevator system,
energy savings and at the same time cost savings are achieved.
[0039] It is possible to place the machine in the free space above
the counterweight, thus increasing the space saving potential of
the elevator.
[0040] By mounting at least the elevator hoisting machine, the
traction sheave and a diverting pulley in a complete unit, which is
fitted as a part of the elevator of the invention, considerable
savings in installation time and costs will be achieved.
[0041] The primary area of application of the invention is
elevators designed for transporting people and/or freight. In
addition, the invention is primarily intended for use in elevators
whose speed range, in the case of passenger elevators, is normally
about or above 1.0 m/s but may also be e.g. only about 0.5 m/s. In
the case of freight elevators, too, the speed is preferably at
least about 0.5 m/s, although slower speeds can also be used with
large loads.
[0042] In both passenger and freight elevators, many of the
advantages achieved through the invention are pronouncedly brought
out even in elevators for only 3-4 people, and distinctly already
in elevators for 6-8 people (500-630 kg).
[0043] The elevator of the invention can be provided with elevator
hoisting ropes twisted e.g. from round and strong wires. From round
wires, the rope can be twisted in many ways using wires of
different or equal thickness. In ropes applicable with the
invention, the wire thickness is below 0.4 mm on an average. Well
applicable ropes made from strong wires are those in which the
average wire thickness is below 0.3 mm or even below 0.2 mm. For
instance, thin-wired and strong 4 mm ropes can be twisted
relatively economically from wires such that the mean wire
thickness in the finished rope is in the range of 0.15 . . . 0.25
mm, while the thinnest wires may have a thickness as small as only
about 0.1 mm. Thin rope wires can easily be made very strong. The
invention employs rope wires having a strength of over 2000
N/mm.sup.2. A suitable range of rope wire strength is 2300-2700
N/mm.sup.2. In principle, it is possible to use rope wires as
strong as about 3000 N/mm or even more.
[0044] By increasing the contact angle using a diverting pulley,
the grip between the traction sheave and the hoisting ropes can be
improved. Therefore, it is possible to reduce the weight of the car
and counterweight and their size can be reduced as well, thus
increasing the space saving potential of the elevator.
Alternatively or at the same time, it is possible to reduce the
weight of the elevator car in relation to the weight of the
counterweight. A contact angle of over 180.degree. between the
traction sheave and the hoisting rope is achieved by using one or
more auxiliary diverting pulleys.
[0045] A preferred embodiment of the elevator of the invention is
an elevator with machine above without machine room, the drive
machine of which comprises a coated traction sheave and which uses
thin hoisting ropes of substantially round cross-section. The
contact angle between the hoisting ropes of the elevator and the
traction sheave is larger than 180.degree.. The elevator comprises
a unit comprising a drive machine, a traction sheave and a
diverting pulley fitted at a correct angle relative to the traction
sheave, all this equipment being fitted on a mounting base. The
unit is secured to the elevator guide rails.
[0046] In the following, the invention will be described in detail
by the aid of a few examples of its embodiments with reference to
the attached drawings, wherein
[0047] FIG. 1 presents a diagram representing a traction sheave
elevator according to the invention,
[0048] FIG. 2 presents a diagram representing another traction
sheave elevator according to the invention,
[0049] FIG. 3 presents a rope sheave applying the invention,
[0050] FIG. 4 presents a coating solution according to the
invention,
[0051] FIG. 5a presents a steel wire rope used in the
invention,
[0052] FIG. 5b presents another steel wire rope used in the
invention,
[0053] FIG. 5c presents a third steel wire rope used in the
invention, and
[0054] FIG. 6 presents a diagram of a rope pulley placement in an
elevator car according to the invention,
[0055] FIG. 7 presents a diagrammatic view of a traction sheave
elevator according to the invention,
[0056] FIG. 8 presents a diagrammatic view of a traction sheave
elevator according to the invention,
[0057] FIG. 9 presents a diagrammatic view of a traction sheave
elevator according to the invention,
[0058] FIGS. 10 present traction sheave roping solutions according
to the invention, and
[0059] FIG. 11 presents an embodiment according to the
invention.
[0060] FIG. 1 is a diagrammatic representation of the structure of
an elevator. The elevator is preferably an elevator without machine
room, with a drive machine 6 placed in the elevator shaft. The
elevator shown in the figure is a traction sheave elevator with
machine above. The passage of the hoisting ropes 3 of the elevator
is as follows: One end of the ropes is immovably fixed to an
anchorage 13 located in the upper part of the shaft above the path
of a counterweight 2 moving along counterweight guide rails 11.
From the anchorage, the ropes run downward and are passed around
diverting pulleys 9 suspending the counterweight, which diverting
pulleys 9 are rotatably mounted on the counterweight 2 and from
which the ropes 3 run further upward via the rope grooves of
diverting pulley 15 to the traction sheave 7 of the drive machine
6, passing around the traction sheave along rope grooves on the
sheave. From the traction sheave 7, the ropes 3 run further
downward back to diverting pulley 15, passing around it along the
rope grooves and returning then back up to the traction sheave 7,
over which the ropes run in the traction sheave rope grooves. From
the traction sheave 7, the ropes 3 go further downwards via the
rope grooves of diverting pulley 15 to the elevator car 1 moving
along the car guide rails 10 of the elevator, passing under the car
via diverting pulleys 4 used to suspend the elevator car on the
ropes, and going then upward again from the elevator car to an
anchorage 14 in the upper part of the elevator shaft, to which
anchorage the second end of the ropes 3 is immovably fixed.
Anchorage 13 in the upper part of the shaft, the traction sheave 7
and the diverting pulley 9 suspending the counterweight on the
ropes are preferably so disposed in relation to each other that
both the rope portion going from the anchorage 13 to the
counterweight 2 and the rope portion going from the counterweight 2
to the traction sheave 7 are substantially parallel to the path of
the counterweight 2. Similarly, a solution is preferred in which
anchorage 14 in the upper part of the shaft, the traction sheave 7,
diverting pulley 15 and the diverting pulleys 4 suspending the
elevator car on the ropes are so disposed in relation to each other
that the rope portion going from the anchorage 14 to the elevator
car 1 and the rope portion going from the elevator car 1 via
diverting pulley 15 to the traction sheave 7 are substantially
parallel to the path of the elevator car 1. With this arrangement,
no additional diverting pulleys are needed to define the passage of
the ropes in the shaft. The roping arrangement between the traction
sheave 7 and the diverting pulley 15 is referred to as Double Wrap
roping, wherein the hoisting ropes are wrapped around the
traction
[0061] sheave two and/or more times. In this way, the contact angle
can be increased in two and/or more stages. For example, in the
embodiment presented in FIG. 1, a contact angle of
180.degree.+180.degree., i.e. 360.degree. between the traction
sheave 7 and the hoisting ropes 3 is achieved. Double Wrap roping
can be arranged in other ways, too, e.g. by placing the diverting
pulley on the side of the traction sheave, in which case, as the
hoisting ropes are passed twice around the traction sheave, a
contact angle of 180.degree.+90.degree.=270.degree. is obtained, or
by placing the diverting pulley at some other appropriate position.
The rope suspension acts in a substantially centric manner on the
elevator car 1, provided that the rope pulleys 4 supporting the
elevator car are mounted substantially symmetrically relative to
the vertical center line passing via the center of gravity of the
elevator car 1. A preferable solution is to dispose the traction
sheave 7 and the diverting pulley 15 in such a way that the
diverting pulley 15 will also function as a guide of the hoisting
ropes 3 and as a damping pulley.
[0062] The drive machine 6 placed in the elevator shaft is
preferably of a flat construction, in other words, the machine has
a small thickness dimension as compared with its width and/or
height, or at least the machine is slim enough to be accommodated
between the elevator car and a wall of the elevator shaft. The
machine may also be placed differently, e.g. by disposing the slim
machine partly or completely between an imaginary extension of the
elevator car and a shaft wall. The elevator shaft is advantageously
provided with equipment required for the supply of power to the
motor driving the traction sheave 7 as well as equipment for
elevator control, both of which can be placed in a common
instrument panel 8 or mounted separately from each other or
integrated partly or wholly with the drive machine 6. The drive
machine may be of a geared or gearless type. A preferable solution
is a gearless machine comprising a permanent magnet motor. Another
advantageous solution is to build a complete unit comprising both
an elevator drive machine with a traction sheave and one or more
diverting pulleys with bearings in a correct operating angle
relative to the traction sheave. The operating angle is determined
by the roping used between the traction sheave an the diverting
pulley/pulleys, which defines the way in which the mutual positions
and angle between the traction sheave and diverting
pulley/diverting pulleys relative to each other are fitted in the
unit. This unit can be mounted in place as a unitary aggregate in
the same way as a drive machine. The drive machine may be fixed to
a wall of the elevator shaft, to the ceiling, to a guide rail or
guide rails or to some other structure, such as a beam or frame. In
the case of an elevator with machine below, a further possibility
is to mount the machine on the bottom of the elevator shaft. FIG. 1
illustrates the economical 2:1 suspension, but the invention can
also be implemented in an elevator using a 1:1 suspension ratio, in
other words, in an elevator in which the hoisting ropes are
connected directly to the counterweight and elevator car without
diverting pulleys. Other suspension arrangements are also possible
in an implementation of the invention. For example, an elevator
according to the invention can be implemented using a suspension
ratio of 3:1, 4:1 or even higher suspension ratios. The
counterweight and the elevator car may also be suspended in such
manner that the counterweight is suspended using a suspension ratio
of n:1 while the elevator car is suspended with a suspension ratio
of m:1, where m is an integer at least equal to 1 and n is an
integer greater than m. The elevator presented in the figure has
automatic telescoping doors, but other types of automatic doors or
turning doors may also be used within the framework of the
invention.
[0063] FIG. 2 presents a diagram representing another traction
sheave elevator according to the invention. In this elevator, the
ropes go upward from the machine. This type of elevator is
generally a traction sheave elevator with machine below. The
elevator car 101 and the counterweight 102 are suspended on the
hoisting ropes 103 of the elevator. The elevator drive machine unit
106 is mounted in the elevator shaft, preferably in the lower part
of the shaft, a diverting pulley 115 is mounted near the drive
machine unit 106, said diverting pulley allowing a sufficiently
large contact angle to be achieved between the traction sheave 107
and the hoisting ropes 103. The hoisting ropes are passed via
diverting pulleys 104,105 provided in the upper part of the
elevator shaft to the car 101 and to the counterweight 102.
Diverting pulleys 104,105 are placed in the upper part of the shaft
and preferably separately mounted with bearings on the same axle so
that they can rotate independently of each other. By way of
example, in the elevator in FIG. 2, Double Wrap roping is also
applied in an elevator with machine below.
[0064] The elevator car 101 and the counterweight 102 move in the
elevator shaft along elevator and counterweight guide rails 110,111
guiding them.
[0065] In FIG. 2, the hoisting ropes run as follows: One end of the
ropes is fixed to an anchorage 112 in the upper part of the shaft,
from where it goes downward to the counterweight 102. The
counterweight is suspended on the ropes 103 via a diverting pulley
109. From the counterweight, the ropes go further upward to a first
diverting pulley 105 mounted on an elevator guide rail 110, and
from the diverting pulley 105 further via the rope grooves of
diverting pulley 115 to the traction sheave 107 driven by the drive
machine 106. From the traction sheave, the ropes go again upwards
to diverting pulley 115, and having wrapped around it they go back
to the traction sheave 107. From the traction sheave 107, the ropes
go again upwards via the rope grooves of diverting pulley 115 to
diverting pulley 104, and having wrapped around this pulley they
pass via diverting pulleys 108 mounted on the top of the elevator
car and then go further to an anchorage 113 in the upper part of
the elevator shaft, where the other end of the hoisting ropes is
fixed. The elevator car is suspended on the hoisting ropes 103 by
means of diverting pulleys 108. In the hoisting ropes 103, one or
more of the rope portions between the diverting pulleys or between
the diverting pulleys and the traction sheave or between the
diverting pulleys and the anchorages may deviate from an exact
vertical direction, a circumstance that makes it easy to provide a
sufficient distance between different rope portions or a sufficient
distance between the hoisting ropes and the other elevator
components. The traction sheave 107 and the hoisting machine 106
are preferably disposed somewhat aside from the path of the
elevator car 101 as well as that of the counterweight 102, so they
can be easily placed almost at any height in the-elevator shaft
below the diverting pulleys 104 and 105. If the machine is not
placed directly above or below the counterweight or elevator car,
this will allow a saving in shaft height. In this case, the minimum
height of the elevator shaft is exclusively determined on the basis
of the length of the paths of the counterweight and elevator car
and the safety clearances needed above and below these. In
addition, a smaller space at the top or bottom of the shaft will be
sufficient due to the reduced rope pulley diameters as compared
with earlier solutions, depending on how the rope pulleys are
mounted on the elevator car and/or on the frame of the elevator
car.
[0066] FIG. 3 presents a partially sectioned view of a rope pulley
200 applying the invention. The rim 206 of the rope pulley is
provided with rope grooves 201, which are covered by a coating 202.
Provided in the hub of the rope pulley is a space 203 for a bearing
used to mount the rope pulley. The rope pulley is also provided
with holes 205 for bolts, allowing the rope pulley to be fastened
by its side to an anchorage in the hoisting machine 6, e.g. to a
rotating flange, to form a traction sheave 7, so that no bearing
separate from the hoisting machine is needed. The coating material
used on the traction sheave and the rope pulleys may consist of
rubber, polyurethane or a corresponding elastic material that
increases friction. The material of the traction sheave and/or rope
pulleys may also be so chosen that, together with the hoisting rope
used, it forms a material pair such that the hoisting rope will
bite into the pulley after the coating on the pulley has been worn
out. This ensures a sufficient grip between the rope pulley 200 and
the hoisting rope 3 in an emergency where the coating 202 has been
worn out from the rope pulley 200. This feature allows the elevator
to maintain its functionality and operational reliability in the
situation referred to. The traction sheave and/or the rope pulleys
can also be manufactured in such manner that only the rim 206 of
the rope pulley 200 is made of a material forming a grip increasing
material pair with the hoisting rope 3. The use of strong hoisting
ropes that are considerably thinner than normally allows the
traction sheave and the rope pulleys to be designed to considerably
smaller dimensions and sizes than when normal-sized ropes are used.
This also makes it possible to use a motor of a smaller size with a
lower torque as the drive motor of the elevator, which leads to a
reduction in the acquisition costs of the motor. For example, in an
elevator according to the invention designed for a nominal load
below 1000 kg, the traction sheave diameter is preferably 120-200
mm, but it may even be less than this. The traction sheave diameter
depends on the thickness of the hoisting ropes used. In the
elevator of the invention, the use of a small traction sheave, e.g.
in the case of elevators for a nominal load below 1000 kg, makes it
possible to achieve a machine weight even as low as about one half
of the weight of currently used machines, which means producing
elevator machines weighing 100-150 kg or even less. In the
invention, the machine is understood as comprising at least the
traction sheave, the motor, the machine housing structures and the
brakes.
[0067] The weight of the elevator machine and its supporting
elements used to hold the machine in place in the elevator shaft is
at most about 1/5 of the nominal load. If the machine is
exclusively or almost exclusively supported by one or more elevator
and/or counterweight guide rails, then the total weight of the
machine and its supporting elements may be less than about 1/6 or
even less than 1/8 of the nominal load. Nominal load of an elevator
means a load defined for elevators of a given size. The supporting
elements of the elevator machine may include e.g. a beam, carriage
or suspension bracket used to support or suspend the machine
on/from a wall structure or ceiling of the elevator shaft or on the
elevator or counterweight guide rails, or clamps used to hold the
machine fastened to the sides of the elevator guide rails. It will
be easy to achieve an elevator in which the machine deadweight
without supporting elements is below {fraction (1/7)} of the
nominal load or even about {fraction (1/10)} of the nominal load or
still less. Basically, the ratio of machine weight to nominal load
is given for a conventional elevator in which the counterweight has
a weight substantially equal to the weight of an empty car plus
half the nominal load. As an example of machine weight in the case
of an elevator of a given nominal weight when the fairly common 2:1
suspension ratio is used with a nominal load of 630 kg, the
combined weight of the machine and its supporting elements may be
only 75 kg when the traction sheave diameter is 160 mm and hoisting
ropes having a diameter of 4 mm are used, in other words, the total
weight of the machine and its supporting elements is about 1/8 of
the nominal load of the elevator. As another example, using the
same 2:1 suspension ratio, the same 160 mm traction sheave diameter
and the same 4 mm hoisting rope diameter, in the case of an
elevator for a nominal load of about 1000 kg, the total weight of
the machine and its supporting elements is about 150 kg, so in this
case the machine and its supporting elements have a total weight
equaling about 1/6 of the nominal load. As a third example, let us
consider an elevator designed for a nominal load of 1600 kg. In
this case, when the suspension ratio is 2:1, the traction sheave
diameter 240 mm and the hoisting rope diameter 6 mm, the total
weight of the machine and its supporting elements will be about 300
kg, i.e. about {fraction (1/7)} of the nominal load. By varying the
hoisting rope suspension arrangements, it is possible to reach a
still lower total weight of the machine and its supporting
elements. For example, when a 4:1 suspension ratio, a 160 mm
traction sheave diameter and a 4 mm hoisting rope diameter are used
in an elevator designed for a nominal load of 500 kg, a total
weight of hoisting machine and its supporting elements of about 50
kg will be achieved. In this case, the total weight of the machine
and its supporting elements is as small as only about {fraction
(1/10)} of the nominal load.
[0068] FIG. 4 presents a solution in which the rope groove 301 is
in a coating 302, which is thinner at the sides of the rope groove
than at the bottom. In such a solution, the coating is placed in a
basic groove 320 provided in the rope pulley 300 so that
deformations produced in the coating by the pressure imposed on it
by the rope will be small and mainly limited to the rope surface
texture sinking into the coating. Such a solution often means in
practice that the rope pulley coating consists of rope
groove-specific sub-coatings separate from each other, but
considering manufacturing or other aspects it may be appropriate to
design the rope pulley coating so that it extends continuously over
a number of grooves.
[0069] By making the coating thinner at the sides of the groove
than at its bottom, the strain imposed by the rope on the bottom of
the rope groove while sinking into the groove is avoided or at
least reduced. As the pressure cannot be discharged laterally but
is directed by the combined effect of the shape of the basic groove
320 and the thickness variation of the coating 302 to support the
rope in the rope groove 301, lower maximum surface pressures acting
on the rope and the coating are also achieved. One method of making
a grooved coating 302 like this is to fill the round-bottomed basic
groove 320 with coating material and then form a half-round rope.
groove 301 in this coating material in the basic groove. The shape
of the rope grooves is well supported and the load-bearing surface
layer under the rope provides a better resistance against lateral
propagation of the compression stress produced by the ropes. The
lateral spreading or rather adjustment of the coating caused by the
pressure is promoted. by thickness and elasticity of the coating
and reduced by hardness and eventual reinforcements of the coating.
The coating thickness on the bottom of the rope groove can be made
large, even as large as half the rope thickness, in which case a
hard and inelastic coating is needed. On the other hand, if a
coating thickness corresponding to only about one tenth of the rope
thickness is used, then the coating material may be clearly softer.
An elevator for eight persons could be implemented using a coating
thickness at the bottom of the groove equal to about one fifth of
the rope thickness if the ropes and the rope load are chosen
appropriately. The coating thickness should equal at least 2-3
times the depth of the rope surface texture formed by the surface
wires of the rope. Such a very thin coating, having a thickness
even less than the thickness of the surface wire of the rope, will
not necessarily endure the strain imposed on it. In practice, the
coating must have a thickness larger than this minimum thickness
because the coating will also have to receive rope surface
variations rougher than the surface texture. Such a rougher area is
formed e.g. where the level differences between rope strands are
larger than those between wires. In practice, a suitable minimum
coating thickness is about 1-3 times the surface wire thickness. In
the case of the ropes normally used in elevators, which have been
designed for a contact with a metallic rope groove and which have a
thickness of 8-10 mm, this thickness definition leads to a coating
at least about 1 mm thick. Since a coating on the traction sheave,
which causes more rope wear than the other rope pulleys of the
elevator, will reduce rope wear and therefore also the need to
provide the rope with thick surface wires, the rope can be made
smoother. Rope smoothness can naturally be improved by coating the
rope with a material suited for this purpose, such as e.g.
polyurethane or equivalent. The use of thin wires allows the rope
itself to be made thinner, because thin steel wires can be
manufactured from a stronger material than thicker wires. For
instance, using 0.2 mm wires, a 4 mm thick elevator hoisting rope
of a fairly good construction can be produced. Depending on the
thickness of the hoisting rope used and/or on other reasons, the
wires in the steel wire rope may preferably have a thickness
between 0.15 mm and 0.5 mm, in which range there are readily
available steel wires with good strength properties in which even
an individual wire has a sufficient wear resistance and a
sufficiently low susceptibility to damage. In the above, -ropes
made of round steel wires have been discussed. Applying the same
principles, the ropes can be wholly or partly twisted from
non-round profiled wires. In this case, the cross-sectional areas
of the wires are preferably substantially the same as for round
wires, i.e. in the range of 0.015 mm.sup.2-0.2 mm. Using wires in
this thickness range, it will be easy to produce steel wire ropes
having a wire strength above about 2000 N/m.sup.2 and a wire
cross-section of 0.015 mm.sup.2-0.2 mm.sup.2 and comprising a large
cross-sectional area of steel material in relation to the
cross-sectional area of the rope, as is achieved e.g. by using the
Warrington construction. For the implementation of the invention,
particularly well suited are ropes having a wire strength in the
range of 2300 N/m.sup.2-2700 N/mm.sup.2, because such ropes have a
very large bearing capacity in relation to rope thickness while the
high hardness of the strong wires involves no substantial
difficulties in the use of the rope in elevators. A traction sheave
coating well suited for such a rope is already clearly below 1 mm
thick. However, the coating should be thick enough to ensure that
it will not be very easily scratched away or pierced e.g. by an
occasional sand grain or similar particle that may have got between
the rope groove and the hoisting rope. Thus, a desirable minimum
coating thickness, even when thin-wire hoisting ropes are used,
would be about 0.5 . . . 1 mm. For hoisting ropes having small
surface wires and an otherwise relatively smooth surface, a coating
having a thickness of the form A+Bcosa is well suited. However,
such a coating is also applicable to ropes whose surface strands
meet the rope groove at a distance from each other, because if the
coating material is sufficiently hard, each strand meeting the rope
groove is in a way separately supported and-the supporting force is
the same and/or as desired. In the formula A+Bcosa, A and B are
constants so that A+B is the coating thickness at the bottom of the
rope groove 301 and the angle a is the angular distance from the
bottom of the rope groove as measured from the center of curvature
of the rope groove cross-section. Constant A is larger than or
equal to zero, and constant B is always larger than zero. The
thickness of the coating growing thinner towards the edges can also
be defined in other ways besides using the formula A+Bcosa so that
the elasticity decreases towards the edges of the rope groove. The
elasticity in the central part of the rope groove can also be
increased by making an undercut rope groove and/or by adding to the
coating on the bottom of the rope groove a portion of different
material of special elasticity, where the elasticity has been
increased, in addition to increasing the material thickness, by the
use of a material that is softer than the rest of the coating.
[0070] FIG. 5a, 5b and 5c present longitudinal cross-sections of
steel wire ropes used in the invention. The ropes in these figures
contain thin steel wires 403, a coating 402 on the steel wires
and/or partly between the steel wires, and in FIG. 5a a coating 401
over the steel wires. The rope presented in FIG. 5b is an uncoated
steel wire rope with a rubber-like filler added to its interior
structure, and FIG. 5a presents a steel wire rope provided with a
coating in addition to a filler added to the internal structure.
The rope presented in FIG. 5c has a non-metallic core 404, which
may be a solid or fibrous structure made of plastic, natural fiber
or some other material suited for the purpose. A fibrous structure
will be good if the rope is lubricated, in which case lubricant
will accumulate in the fibrous core. The core thus acts as a kind
of lubricant storage. The steel wire ropes of substantially round
cross-section used in the elevator of the invention may be coated,
uncoated and/or provided with a rubber-like filler, such as e.g.
polyurethane or some other suitable filler, added to the interior
structure of the rope and acting as a kind of lubricant lubricating
the rope and also balancing the pressure between wires and strands.
The use of a filler makes it possible to achieve a rope that needs
no lubrication, so its surface can be dry. The coating used in the
steel wire ropes may be made of the same or nearly the same
material as the filler or of a material that is better suited for
use as a coating and has properties, such as friction and wear
resistance properties, that are better suited to the purpose than a
filler. The coating of the steel wire rope may also be so
implemented that the coating material penetrates partially into the
rope or through the entire thickness of the rope, giving the rope
the same properties as the filler mentioned above. The use of thin
and strong steel wire ropes according to the invention is possible
because the steel wires used are wires of special strength,
allowing the ropes to be made substantially thin as compared with
steel wire ropes used before. The ropes presented in FIG. 5a and 5b
are steel wire ropes having a diameter of about 4 mm. For example,
when a 2:1 suspension ratio is used, the thin and strong steel wire
ropes of the invention preferably have a diameter of about 2.5-5 mm
in elevators for a nominal load below 1000 kg, and preferably about
5-8 mm in elevators for a nominal load above 1000 kg. In principle,
it is possible to use ropes thinner than this, but in this case a
large number of ropes will be needed. Still, by increasing the
suspension ratio, ropes thinner than those mentioned above can be
used for corresponding loads, and at the same time a smaller and
lighter elevator machine can be achieved.
[0071] FIG. 6 illustrates the manner in which a rope pulley 502
connected to a horizontal beam 504 comprised in the structure
supporting the elevator car 501 is placed in relation to the beam
504, said rope pulley being used to support the elevator car and
associated structures. The rope pulley 502 presented in the figure
may have a diameter equal to or less than the height of the beam
504 comprised in the structure. The beam 504 supporting the
elevator car 501 may be located either below or above the elevator
car. The rope pulley 502 may be placed completely or partially
inside the beam 504, as shown in the figure. The hoisting ropes 503
of the elevator in the figure run as follows: The hoisting ropes
503 come to the coated rope pulley 502 connected to the beam 504
comprised in the structure supporting the elevator car 501, from
which pulley the hoisting rope runs further, protected by the beam,
e.g. in a hollow 506 inside the beam, under the elevator car and
goes then further via a second rope pulley placed on the other side
of the elevator car. The elevator car 501 rests on the beam 504
comprised in the structure, on vibration absorbers 505 placed
between them. The beam 504 also acts as a rope guard for the
hoisting rope 503. The beam 504 may be a C-, U-, I-, Z-section beam
or a hollow beam or equivalent.
[0072] FIG. 7 presents a diagrammatic illustration of the structure
of an elevator according to the invention. The elevator is
preferably an elevator without machine room, with a drive machine
706 placed in the elevator shaft. The elevator shown in the figure
is a traction sheave elevator with machine above. The passage of
the hoisting ropes 703 of the elevator is as follows: One end of
the ropes is immovably fixed to an anchorage 713 located in the
upper part of the shaft above the path of a counterweight 702
moving along counterweight guide rails 711. From the anchorage, the
ropes run downwards to diverting pulleys 709 suspending the
counterweight, which are rotatably mounted on the counterweight 702
and from which the ropes 703 run further upward via the rope
grooves of diverting pulley 715 to the traction sheave 707 of the
drive machine 706, passing around the traction sheave along the
rope grooves on the sheave. From the traction sheave 707, the ropes
703 run further downwards back to diverting pulley 715, wrapping
around it along the rope grooves of the diverting pulley and
returning then back up to the traction sheave 707, over which the
ropes run in the traction sheave rope grooves. From the traction
sheave 707, the ropes 703 go further downwards via the rope grooves
of the diverting pulley to the elevator car 701 moving along the
car guide rails 710 of the elevator, passing under the car via
diverting pulleys 704 used to suspend the elevator car on the
ropes, and going then upwards again from the elevator car to an
anchorage 714 in the upper part of the elevator shaft, to which
anchorage the second end of the ropes 703 is immovably fixed.
Anchorage 713 in the upper part of the shaft, the traction sheave
707, diverting pulley 715 and the diverting pulley 709 suspending
the counterweight on the ropes are preferably so disposed in
relation to each other that both the rope portion going from the
anchorage 713 to the counterweight 702 and the rope portion going
from the counterweight 702 via diverting pulley 715 to the traction
sheave 707 are substantially parallel to the path of the
counterweight 702. Similarly, a solution is preferred in which the
anchorage 714 in the upper part of the shaft, the traction sheave
707, diverting pulleys 715,712 and the diverting pulleys 704
suspending the elevator car on the ropes are so disposed in
relation to each other that the rope portion going from the
anchorage 714 to the elevator car 701 and the rope portion going
from the elevator car 701 via diverting pulley 715 to the traction
sheave 707 are substantially parallel to the path of the elevator
car 701. With this arrangement, no additional diverting pulleys are
needed to define the passage of the ropes in the shaft. The roping
arrangement between the traction sheave 707 and the diverting
pulley 715 is referred to as Double Wrap roping, wherein the
hoisting ropes are wrapped around the traction sheave two and/or
more times. In this way, the contact angle can be increased in two
and/or more stages. For example, in the embodiment presented in
FIG. 7, a contact angle of 180.degree.+180.degree., i.e.
360.degree. between the traction sheave 707 and the hoisting ropes
703 is achieved. The rope suspension acts in a substantially
centric manner on the elevator car 701, provided that the rope
pulleys 704 suspending the elevator car are mounted substantially
symmetrically relative to the vertical center line passing via the
center of gravity of the elevator car 701. A preferable solution is
to dispose the traction sheave 707 and the diverting pulley 715 in
such a way that the diverting pulley 715 will also function as a
guide of the hoisting ropes 703 and as a damping pulley.
[0073] The drive machine 706 placed in the elevator shaft is
preferably of flat construction, in other words, the machine has a
small thickness dimension as compared with its width and/or height,
or at least the machine is slim enough to be accommodated between
the elevator car and a wall of the elevator shaft. The machine may
also be placed differently, e.g. by disposing the slim machine
partly or completely between an imaginary extension of the elevator
car and a shaft wall. The elevator shaft is advantageously provided
with equipment required for the supply of power to the motor
driving the traction sheave 707 as well as equipment needed for
elevator control, both of which can be placed in a common
instrument panel 708 or mounted separately from each other or
integrated partly or wholly with the drive machine 706. The drive
machine may be of geared or gearless type. A preferable solution is
a gearless machine comprising a permanent magnet motor. Another
advantageous solution is to build a complete unit comprising both
the elevator drive machine 706 and the diverting pulley 715 and its
bearings, which is used to increase the contact angle, in a correct
operating angle relative to the traction sheave 707, which unit can
be mounted in place as a unitary aggregate in the same way as a
drive machine. The drive machine may be fixed to a wall of the
elevator shaft, to the ceiling, to a guide rail or guide rails or
to some other structure, such as a beam or frame. The diverting
pulley/diverting pulleys to be placed near the drive machine to
increase the operating angle can be mounted in the same way. In the
case of an elevator with machine below, a further possibility is to
mount the above-mentioned components on the bottom of the elevator
shaft. In Double Wrap roping, when diverting pulley 715 is of
substantially equal size with the traction sheave 707, diverting
pulley 715 can also function as a damping wheel. In this case, the
ropes going from the traction sheave 707 to the counterweight 702
and to the elevator car 701 are passed via the rope grooves of the
diverting pulley 715 and the rope deflection caused by the
diverting pulley is very small. It could be said that the ropes
coming from the traction sheave only touch the diverting pulley
tangentially. Such tangential contact serves as a solution damping
the vibrations of outgoing ropes and it can applied in other roping
solutions as well. An example of these other roping solutions is
Single Wrap (SW) roping, where the diverting pulley is of
substantially equal size with the traction sheave of the drive
machine and where a diverting pulley used for tangential rope
contact as described above. In SW roping according to the example,
the ropes wrap around the traction sheave only once, with a contact
angle of about 180.degree. between the rope and the traction
sheave, the diverting pulley is only used as a means of producing a
tangential contact as described above and the diverting pulley
functions as a rope guide and as a damping wheel for the damping of
vibrations. The suspension ratio of the elevator is of no
importance with respect to the application of SW roping described
in the example; instead, it can be used in connection with any
suspension ratio. The embodiment using SW roping as described in
the example may have an inventive value in itself, at least in
regard of damping. The diverting pulley 715 may also be of
substantially different size than the traction sheave, in which
case it functions as a diverting pulley increasing the contact
angle and not as a damping wheel. FIG. 7 presents an elevator
according to the invention that uses a suspension ratio of 4:1. The
invention can also be implemented using other suspension
arrangements. For example, an elevator according to the invention
can be implemented using a suspension ratio of 1:1, 2:1, 3:1 or
even suspension ratios higher than 4:1. The elevator presented in
the figure has automatic telescoping doors, but other types of
automatic doors or turning doors may also be used within the
framework of the invention.
[0074] FIG. 8 presents a diagrammatic illustration of the structure
of an elevator according to the invention. The elevator is
preferably an elevator without machine room, with a drive machine
806 placed in the elevator shaft. The elevator shown in the figure
is a traction sheave elevator with machine above. The passage of
the hoisting ropes 803 of the elevator is as follows: One end of
the ropes is immovably fixed to an anchorage 813 located in the
upper part of the shaft above the path of a counterweight 802
moving along counterweight guide rails 811. From the anchorage, the
ropes run downwards to diverting pulleys 809 suspending the
counterweight, which are rotatably mounted on the counterweight
.802 and from which the ropes 803 run further upward via the rope
grooves of diverting pulley 815 to the traction sheave 807 of the
drive machine 806, wrapping around the traction sheave along the
rope grooves on the sheave. From the traction sheave 807, the ropes
803 run further downwards, going crosswise relative to the upwards
going ropes, and further via the rope grooves of the diverting
pulley to the elevator car 801 moving along the car guide rails 810
of the elevator, passing under the car via diverting pulleys 804
used to suspend the elevator car on the ropes, and going then
upwards again from the elevator car to an anchorage 814 in the
upper part of the elevator shaft, to which anchorage the second end
of the ropes 803 is immovably fixed. Anchorage 813 in the upper
part of the shaft, the traction sheave 807, diverting pulley 815
and the diverting pulley 809 suspending the counterweight on the
ropes are preferably so disposed in relation to each other that
both the rope portion going from the anchorage 813 to the
counterweight 802 and the rope portion going from the counterweight
802 via diverting pulley 815 to the traction sheave 807 are
substantially parallel to the path of the counterweight 802.
Similarly, a solution is preferred in which the anchorage 814 in
the upper part of the shaft, the traction sheave 807, diverting
pulley 815 and the diverting pulleys 804 suspending the elevator
car on the ropes are so disposed in relation to each other that the
rope portion going from the anchorage 814 to the elevator car 801
and the rope portion going from the elevator car 801 via diverting
pulley 815 to the traction sheave 807 are substantially parallel to
the path of the elevator car 801. With this arrangement, no
additional diverting pulleys are needed to define the passage of
the ropes in the shaft. This roping arrangement between the
traction sheave 807 and the diverting pulley 815 can be referred to
as X Wrap (XW) roping, while Double Wrap (DW) roping, Single Wrap
(SW) roping and Extended Wrap (ESW) roping are previously known
concepts. In X Wrap roping, the ropes are caused to wrap around the
traction sheave with a large contact angle. For example, in the
case illustrated in FIG. 8, a contact angle of well over
180.degree., i.e. about 270.degree. between the traction sheave 807
and the hoisting ropes 803 is achieved. X Wrap roping presented in
the figure can also be arranged in another way, e.g. by providing
two diverting pulleys at appropriate positions near the drive
machine. Diverting pulley 815 has been fitted in a position
designed to form an angle relative to the traction sheave 807 such
that the ropes will run crosswise in a manner known in itself so
that the ropes are not damaged. The rope suspension acts in a
substantially centric manner on the elevator car 801, provided that
the rope pulleys 804 suspending the elevator car are mounted
substantially symmetrically relative to the vertical center line
passing via the center of gravity of the elevator car 801.
[0075] The drive machine 806 placed in the elevator shaft is
preferably of flat construction, in other words, the machine has a
small thickness dimension as compared with its width and/or height,
or at least the machine is slim enough to be accommodated between
the elevator car and a wall of the elevator shaft. The machine may
also be placed differently, e.g. by disposing the slim machine
partly or completely between an imaginary extension of the elevator
car and a shaft wall. The elevator shaft is advantageously provided
with equipment required for the supply of power to the motor
driving the traction sheave 807 as well as equipment needed for
elevator control, both of which can be placed in a common
instrument panel 808 or mounted separately from each other or
integrated partly or wholly with the drive machine 806. The drive
machine may be of geared or gearless type. A preferable solution is
a gearless machine comprising a permanent magnet motor. Another
advantageous solution is to build a complete unit comprising both
the elevator drive machine 806 and the diverting pulley 815 and its
bearings, which is used to increase the contact angle, in a correct
operating angle relative to the traction sheave 807, which unit can
be mounted in place as a unitary aggregate in the same way as a
drive machine. Using a complete unit means less need for rigging
during installation. X Wrap roping can also be implemented by
mounting a diverting pulley directly on the drive machine. The
drive machine may be fixed to a wall of the elevator shaft, to the
ceiling, to a guide rail or guide rails or to some other structure,
such as a beam or frame. The diverting pulley to. be placed near
the drive machine to increase the operating angle can be mounted in
the same way. In the case of an elevator with machine below, a
further possibility is to mount the above-mentioned components on
the bottom of the elevator shaft. FIG. 8 illustrates the economical
2:1 suspension, but the invention can also be implemented in an
elevator with 1:1 suspension ratio, in other words, in an elevator
with the hoisting ropes connected directly to the counterweight and
elevator car without a diverting pulley. The invention can also be
implemented using other suspension arrangements. For example, an
elevator according to the invention can be implemented using a
suspension ratio of 3:1, 4:1 or even higher suspension ratios. The
elevator presented in the figure has automatic telescoping doors,
but other types of automatic doors or turning doors may also be
used within the framework of the invention.
[0076] FIG. 9 presents a diagrammatic illustration of the structure
of an elevator according to the invention. The elevator is
preferably an elevator without machine room, with a drive machine
906 placed in the elevator shaft. The elevator shown in the figure
is a traction sheave elevator with machine above. The passage of
the hoisting ropes 903 of the elevator is as follows: One end of
the ropes is immovably fixed to an anchorage 913 located in the
upper part of the shaft above the path of a counterweight 902
moving along counterweight guide rails 911. From the anchorage, the
ropes run downwards to diverting pulleys. 909 suspending the
counterweight, which are rotatably mounted on the counterweight 902
and from which diverting pulleys 909 the ropes 903 run further
upward to the traction sheave 907 of the drive machine 906,
wrapping around the traction sheave along the rope grooves on the
sheave. From,the traction sheave 907, the ropes 903 run further
downwards, going crosswise relative to the upwards going ropes, and
further to diverting pulley 915, wrapping around it along the rope
grooves of the diverting pulley 915. From the diverting pulley 915,
the ropes go further downwards to the elevator car 901 moving along
the car guide rails 910 of the elevator, passing under the car via
diverting pulleys 904 used to suspend the elevator car on the
ropes, and going then upwards again from the elevator car to an
anchorage 914 in the upper part of the elevator shaft, to which
anchorage the second end of the ropes 903 is immovably fixed.
Anchorage 913 in the upper. part of the shaft, the traction sheave
907 and the diverting pulley 909 suspending the counterweight on
the ropes are preferably so disposed in relation to each other that
both the rope portion going from the anchorage 913 to the
counterweight 902 and the rope portion going from the counterweight
902 to the traction sheave 907 are substantially parallel to the
path of the counterweight 902. Similarly, a solution is preferred
in which the anchorage 914 in the upper part. of the shaft, the
traction sheave 907, diverting pulley 915 and the diverting pulleys
904 suspending the elevator car on the ropes are so disposed in
relation to each other that the rope portion going from the
anchorage 914 to the elevator car 901 and the rope portion going
from the elevator car 901 via diverting pulley 915 to the traction
sheave 907 are substantially parallel to the path of the elevator
car 901. With this arrangement, no additional diverting pulleys are
needed to define the passage of the ropes in the shaft. This roping
arrangement between the traction sheave 907 and the diverting
pulley 915 can be referred to as Extended Single Wrap roping. In
Extended Single Wrap roping, by using a diverting pulley, the
hoisting ropes are caused to wrap around the traction sheave with a
larger contact angle. For example, in the case illustrated in FIG.
9, a contact angle of well over 180.degree., i.e. about 270.degree.
between the traction sheave 907 and the hoisting ropes 903 is
achieved. Extended Single Wrap roping presented in the figure can
also be arranged in another way, e.g. by disposing the drive
machine and the diverting pulley in another way in relation to each
other, e.g. the other way round relative to each other than in the
case presented in FIG. 9. Diverting pulley 915 has been fitted in a
position designed to form an angle relative to the traction sheave
907 such that the ropes will run crosswise in a manner known in
itself so that the ropes are not damaged. The rope suspension acts
in a substantially centric manner on the elevator car 901, provided
that the rope pulleys 904 suspending the elevator car are mounted
substantially symmetrically relative to the vertical center line
passing via the center of gravity of the elevator car 901. In the
solution represented by FIG. 9, the drive machine 906 can
preferably be placed e.g. in the free space above the
counterweight, thereby increasing the space saving potential of the
elevator.
[0077] The drive machine 906 placed in the elevator shaft is
preferably of flat construction, in other words, the machine has a
small thickness dimension as compared with its width and/or height,
or at least the machine is slim enough to be accommodated between
the elevator car and a wall of the elevator shaft. The machine may
also be placed differently, e.g. by disposing the slim machine
partly or completely between an imaginary extension of the elevator
car and a shaft wall. The elevator shaft is advantageously provided
with equipment required for the supply of power to the motor
driving the traction sheave 907 as well as equipment needed for
elevator control, both of which can be placed in a common
instrument panel 908 or mounted separately from each other or
integrated partly or wholly with the drive machine. 906. The drive
machine may be of geared or gearless type. A preferable solution is
a gearless machine comprising a permanent magnet motor. Another
advantageous solution is to build a complete unit comprising both
the elevator drive machine 906 and/or the diverting
pulley/diverting pulleys 915 with their bearings, mounted in a
correct operating angle relative to the traction sheave 907 to
increase the contact angle, all this equipment being ready fitted
on a mounting base, which unit can be mounted in place as a unitary
aggregate in the same way as a drive machine. Using a unitary
aggregate solution reduces the need for rigging at installation
time. The drive machine may be fixed to a wall of the elevator
shaft, to the ceiling, to a guide rail or guide rails or to some
other structure, such as a beam or frame. The diverting pulley to
be placed near the drive machine to increase the operating angle
can be mounted in the same way. In the case of an elevator with
machine below, a further possibility is to mount the
above-mentioned components on the bottom of the elevator shaft.
FIG. 9 illustrates the economical 2:1 suspension, but the invention
can also be implemented in an elevator with 1:1 suspension ratio,
in other words, in an elevator with the hoisting ropes connected
directly to the counterweight and elevator car without a diverting
pulley. The invention can also be implemented using other
suspension arrangements. For example, an elevator according to the
invention can be implemented using a suspension ratio of 3:1, 4:1
or even higher suspension ratios. The elevator presented, in the
figure has automatic telescoping doors, but other types of
automatic doors or turning doors may also be used within the
framework of the invention. FIGS. 10a, 10b, 10c, 10d, 10e, 10f and
10g present some variations of the roping arrangements according to
the invention that can be used between the traction sheave 1007 and
the diverting pulley 1015 to increase the contact angle between the
ropes 1003 and the traction sheave 1007, in which arrangements the
ropes 1003 go downwards from the drive machine 1006 towards the
elevator car and counterweight. These roping arrangements make it
possible to increase the: contact angle between the hoisting rope
1003 and the traction sheave 1007. In the invention, contact angle
a refers to the length of the arc of contact between the traction
sheave and the hoisting rope. The magnitude of the contact angle
.alpha. may be expressed e.g. in degrees, as is done in the
invention, but it is also possible to express the magnitude of the
contact angle in other terms, e.g. in radians or equivalent. The
contact angle .alpha. is presented in greater detail in FIG. 10a.
In the other figures, the contact angle .alpha. is not expressly
indicated, but it can be seen from the other figures as well
without specific description.
[0078] The roping arrangements presented in FIG. 10a, 10b, 10c
represent some variations of the X Wrap roping described above. In
the arrangement presented in FIG. 10a, the ropes 1003 come via
diverting pulley 1015, wrapping around it along rope grooves, to
the traction sheave 1007, over which the ropes pass along its rope
grooves and then go further back to the diverting pulley 1015,
passing crosswise with respect to the rope portion coming from the
diverting pulley, and continuing their passage further. Crosswise
passage of the ropes 1003 between the diverting pulley 1015 and the
traction sheave 1007 can be implemented e.g. by having the
diverting pulley fitted at such an angle with respect to the
traction sheave that the ropes will cross each other in a manner
known in itself so that the ropes 1003 are not damaged. In FIG.
10a, the contact angle .alpha. between the ropes 1003 and the
traction sheave 1007 is represented by the shaded area. The
magnitude of the contact angle .alpha. in this figure is about
310.degree.. The size of the diameter of the diverting pulley can
be used as a means of determining the distance of suspension that
is to be provided between the diverting pulley 1015 and the
traction sheave 1007. The magnitude of the contact angle can be
varied by varying the distance between the diverting pulley 1015
and the traction sheave 1007. The magnitude of the angle .alpha.
can also be varied by varying the diameter of the diverting pulley
and/or by varying the diameter of the traction sheave and also by
varying the relation between the diameters of the diverting pulley
and the traction sheave. FIG. 10b and 10c present an example of
implementing a corresponding XW roping arrangement using two
diverting pulleys.
[0079] The roping arrangements presented in FIG. 10d and 10e are
different variations of the above-mentioned Double Wrap roping. In
the roping arrangement in FIG. 10d, the ropes run via the rope
grooves of diverting pulley 1015 to the traction sheave traction
sheave 1007 of the drive machine 1006, passing over it along the
rope grooves of the traction sheave. From the traction sheave 1007,
the ropes 1003 go further downwards back to diverting pulley 1015,
wrapping around it along the rope grooves of the diverting pulley
and returning then back to the traction sheave 1007, over which the
ropes run in the rope grooves of the traction sheave. From the
traction sheave 1007, the ropes 1003 run further downwards via the
rope grooves of the diverting pulley. In the roping arrangement
presented in the figure, the hoisting ropes are caused to wrap
around the traction sheave twice and/or more times. By these means,
the contact angle can be increased in two and/or more stages. For
example, in the case presented in FIG. 10d, a contact angle of
180.degree.+180.degree. between the traction sheave 1007 and the
ropes 1003 is achieved. In Double Wrap roping, when the diverting
pulley 1015 is substantially of equal size with the traction sheave
1007, the diverting pulley 1015 also functions as a damping wheel.
In this case, the ropes going from the traction sheave 1007 to the
counterweight and elevator car pass via the rope grooves of the
diverting pulley 1015 and the rope deflection produced by the
diverting pulley is very small. It could be said that the ropes
coming from the traction sheave only touch the diverting pulley
tangentially. Such tangential contact serves as a solution damping
the vibrations of outgoing ropes and it can applied in other roping
arrangements as well. In this case, the diverting pulley 1015 also
functions as a rope guide. The ratio of the diameters of the
diverting pulley and traction sheave can be varied by varying the
diameters of the diverting pulley and/or traction sheave. This can
be used as a means of defining the magnitude of the contact angle
and fitting it to a desired magnitude. By using DW roping, forward
bending of the rope 1003 is achieved, which means that the rope
1003 is in DW roping is bent in the same direction on the diverting
pulley 1015 and on the traction sheave 1007. DW roping can also be
implemented in other ways, such as e.g. the way illustrated in FIG.
10e, where the diverting pulley 1015 is disposed on the side of the
traction sheave 1007. In this roping arrangement, the ropes 1003
are passed in a manner corresponding to FIG. 10d, but in this case
a contact angle of 180.degree.+90.degree., i.e. 270.degree. is
obtained. If the diverting pulley 1015 is placed on the side of the
traction sheave in the case of DW roping, greater demands are
imposed on the bearings and mounting of the diverting pulley
because it is exposed to greater stress and load forces than in the
embodiment presented in FIG. 10d.
[0080] FIG. 10f presents an embodiment of the invention applying
Extended Single Wrap roping as mentioned above. In the roping
arrangement presented in the figure, the ropes 1003 run to the
traction sheave 1007 of the drive machine 1006, wrapping around it
along the rope grooves of the traction sheave. From the traction
sheave 1007, the ropes 1003 go further downwards, running crosswise
relative to the upwards going ropes and further to diverting pulley
1015, passing over it along the rope grooves of the diverting
pulley 1015. From the diverting pulley 1015, the ropes 1003 run
further on. In Extended Single Wrap roping, by using a diverting
pulley, the hoisting ropes are caused to wrap around the traction
sheave with a larger contact angle than in ordinary Single Wrap
roping. For example, in the case illustrated in FIG. 10f, a contact
angle of about 270.degree. between the ropes 1003 and the traction
sheave 1007 is obtained. The diverting pulley 1015 is fitted in
position at an angle such that the ropes run crosswise in a manner
known in itself, so that the ropes are not damaged. By virtue of
the contact angle achieved using Extended Single Wrap roping,
elevators implemented according to the invention can use a very
light elevator car and the elevator drive machine can be placed
e.g. in the free space above the counterweight, thus allowing freer
disposition of other elevator components because there is more
space available. One possibility of increasing the contact angle is
illustrated in FIG. 10g, where the hoisting ropes do not run
crosswise relative to each other after wrapping around the traction
sheave and/or diverting pulley. By using a roping arrangement like
this, it is also possible increase the contact angle between the
hoisting ropes 1003 and the traction sheave 1007 of the drive
machine 1006 to a magnitude substantially over 180.degree..
[0081] FIGS. 10a,b,c,d,f and g present different variations of
roping arrangements between the traction sheave and the diverting
pulley/diverting pulleys, in which the ropes go downwards from the
drive machine towards the counterweight and the elevator car. In
the case of an elevator embodiment according to the invention with
machine below, these roping arrangements can be inverted and
implemented in a corresponding manner so that the ropes go upwards
from the elevator drive machine towards the counterweight and the
elevator car. FIG. 11 presents yet another embodiment of the
invention, wherein the elevator drive machine 1106 is fitted
together with a diverting pulley 1115 on the same mounting base
1121 in a ready-made unit 1120, which can be fitted as such to form
a part of an elevator according to the invention. The unit contains
the elevator drive machine 1106, the traction sheave 1107 and
diverting pulley 1115 ready-fitted on the mounting base 1121, the
traction sheave and diverting pulley being ready fitted at a
correct operating angle relative to each other, depending on the
roping arrangement used between the traction sheave 1107 and the
diverting pulley 1115. The unit 1120 may comprise more than only
one diverting pulley 1115, or it may only comprise the drive
machine 1106 fitted on the mounting base 1121. The unit can be
mounted in an elevator according to the invention like a drive
machine, the mounting arrangement being described in greater detail
in connection with the previous figures. If necessary, the unit can
be used together with any of the roping arrangements described
above, such as e.g. embodiments using ESW, DW, SW or XW roping. By
fitting the above-described unit as part of an elevator according
to the invention, considerable savings can be made in installation
costs and in the time required for installation.
[0082] It is obvious to the person skilled in the art that
different embodiments of the invention are not limited to the
examples described above, but that they may be varied within the
scope of the following claims. For instance, the number of times
the hoisting ropes are passed between the upper part of the
elevator shaft and the counterweight or elevator car is not a very
decisive question as regards the basic advantages of the invention,
although it is possible to achieve some additional advantages by
using multiple rope passages. In general, embodiments should be so
implemented that the ropes go to the elevator car at most as many
times as to the counterweight. It is also obvious that the hoisting
ropes need not necessarily be passed under the car; instead, they
may also be passed over or sideways past the elevator car. In
accordance with the examples described above, the skilled person
can vary the embodiment of the invention, while the traction
sheaves and rope pulleys, instead of being coated metal pulleys,
may also be uncoated metal pulleys or uncoated pulleys made of some
other material suited to the purpose.
[0083] It is further obvious to the person skilled in the art that
the metallic traction sheaves and rope pulleys used in the
invention, which are coated with a nonmetallic material at least in
the area of their grooves, may be implemented using a coating
material consisting of e.g. rubber, polyurethane or some other
material suited to the purpose.
[0084] It is also obvious to the person skilled in the art that the
elevator car, the counterweight and the machine unit may be laid
out in the cross-section of the elevator shaft in a manner
differing from the lay-out described in the examples. Such a
different lay-out might be e.g. one in which the machine and the
counterweight are located behind the car as seen from the shaft
door and the ropes are passed under the car diagonally relative to
the bottom of the car. Passing the ropes under the car in a
diagonal or otherwise oblique direction relative to the form of the
bottom provides an advantage when the suspension of the car on the
ropes is to be made symmetrical relative to the center of mass of
the elevator in other types of suspension lay-out as well.
[0085] It is further obvious to the person skilled in the art that
the equipment required for the supply of power to the motor and the
equipment needed for elevator control can be placed elsewhere than
in connection with the machine unit, e.g. in a separate instrument
panel. It is also possible to fit pieces of equipment needed for
control into separate units which can then be disposed in different
places in the elevator shaft and/or in other parts of the building.
It is likewise obvious to the skilled person that an elevator
applying the invention may be equipped differently from the
examples described above. It is further obvious to the skilled
person that the suspension solutions according to the invention can
also be implemented using some other type of flexible hoisting
means as hoisting ropes than the means described here, to achieve
small deflection diameters of the hoisting means, for example by
using flexible rope of one or more strands, flat belt, cogged belt,
trapezoidal belt or some other type of belt applicable to the
purpose, or even using different types of chains.
[0086] It is also obvious to the skilled person that, instead of
using ropes with a filler as illustrated in FIG. 5a and 5b, the
invention may be implemented using ropes without filler, which are
either lubricated or unlubricated. In addition, it is also obvious
to the person skilled in the art that the ropes may be twisted in
many different ways. It is also obvious to the skilled person that
the average of the wire thicknesses may be understood as referring
to a statistical, geometrical or arithmetical mean value. To
determine a statistical average, the standard deviation or Gauss
distribution can be used. It is further obvious that the wire
thicknesses in the rope may vary, e.g. even by a factor of 3 or
more.
[0087] It is also obvious to the person skilled in the art that the
elevator of the invention can be implemented using different roping
arrangements for increasing the contact angle .alpha. between the
traction sheave and the diverting pulley/diverting pulleys than
those described as examples. For example, it is possible to dispose
the diverting pulley/diverting pulleys, the traction sheave and the
hoisting ropes in other ways than in the roping arrangements
described in the examples.
* * * * *