BACKGROUND OF THE INVENTION
[0001] The present invention relates to an elevator system in which a car and a counter
weight are moved along guide rails in an elevator shaft.
DESCRIPTION OF RELATED ART
[0002] Heretofore, there has been proposed an elevator system in which a car and a counterweight
are suspended by 3:1 roping. For example,
JP-A-2004-83231 teaches in paragraph 0023, Fig. 1, Fig. 7, etc. that the tension exerted to a rope
becomes two third (2/3) as compared with a conventional 2:1 roping elevator system,
the wind-up torque required of a drive unit is reduced and therefore the drive unit
can be made small.
[0003] However, in the elevator system disclosed in the above-mentioned patent document,
the vertical projection of an end of the drive unit on the side remote from a sheave
protrudes beyond the vertical projection of the car. Thus, when a worker on the car
does maintenance such as inspection or replacement for a brake section or a position
detector of the drive unit on the side remote from the sheave, a space in front of
the brake section or the position detector is too narrow to conveniently carry out
the work.
SUMMARY OF THE INVENTION
[0004] An object of the present invention is to provide an elevator system having a small-sized
drive unit which facilitates maintenance of a brake section and a position detector
thereof.
[0005] To attain the above end, the present invention provides an elevator system having
a car and a counter weight suspended by a rope within an elevator shaft and driven
by a hoist, which comprises a suspending pulley provided on the upper part of the
car, a rope hitch provided on the car, a suspending pulley provided on the upper part
of the counterweight, and a rope hitch provided on the upper part of the counter weight,
wherein the vertical projection of a sheave of the hoist is not overlapped with that
of the car while the vertical projection of a brake section on the side remote from
the sheave lies within that of the car.
[0006] Further, the invention provides an elevator system having a car and a counter weight
suspended in an elevator shaft by a rope and driven by a hoist, which comprises a
suspending pulley provided on the upper part of the car, a rope hitch provided on
the car, a suspending pulley provided on the upper part of the counter weight, and
a rope hitch provided on the upper part of the counter weight, wherein the vertical
projection of a sheave of the hoist is not overlapped with that of the car, and the
vertical projection of an end of a position detector of the hoist on the side remote
from the sheave lies within that of the car.
[0007] According to the invention, it is possible to provide the elevator system in which
a drive unit is small and maintenance of the brake section and the position detector
is facilitated.
[0008] Other objects, features and advantages of the invention will become apparent from
the following description of embodiments of the invention taken in conjunction with
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
Fig. 1 is a view for explaining how to wind a rope in an elevator system of the first
embodiment of the invention.
Fig. 2 is a horizontal sectional view of illustrating an elevator shaft in the elevator
system of the first embodiment of the invention.
Fig. 3 is a sectional view of a hoist in the elevator system of the first embodiment
of the invention.
Fig. 4 is a right side view of the elevator shaft in the elevator system of the first
embodiment of the invention.
Fig. 5 is a front view of the elevator shaft in the elevator system of the first embodiment
of the invention.
Fig. 6 is a view explaining how to wind a rope 5 in an elevator system of the second
embodiment of the invention.
Fig. 7 is a horizontal sectional view of an elevator shaft in the elevator system
of the second embodiment of the invention.
Fig. 8 is an external view of a hoist in the elevator system of the second embodiment
of the invention.
Fig. 9 is a right side view of the elevator shaft in the elevator system of the second
embodiment of the invention.
Fig. 10 is a front view of the elevator shaft in the elevator system of the second
embodiment of the invention.
Fig. 11 is a front view of an elevator shaft in an elevator system of the third embodiment
of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] Explanation will be hereinbelow made on embodiments of the invention with reference
to the accompanying drawing.
[0011] Fig. 1 is a view for explaining how to wind a rope 5 in the elevator system showing
the first embodiment of the invention. Fig. 2 is a horizontal sectional view of an
elevator shaft in the elevator system of the embodiment, and Fig. 3 is a sectional
view illustrating a hoist in the elevator system of the embodiment. Fig. 4 is a right
side view of the elevator shaft in the elevator system of the embodiment, and Fig.
5 is a front view of the elevator shaft in the elevator system of the embodiment.
[0012] The elevator system of the embodiment has a configuration in which a car 1 is moved
up and down along guide rails 16a, 16b while a counter weight 12 is moved up and down
along guide rails 17a, 17b. The car 1 and a counter weight 12 are suspended by the
rope 5 and are driven by a flat type hoist 10. The flat type hoist referred to herein
means a hoist having a shorter length in the direction of a rotational axis than a
length in a direction orthogonal to the rotational axis. Further, an inward direction
of the car 1 herein means the direction perpendicular to a car door 2, and the direction
of coming away from the car door 2 in the elevator shaft will be referred to as rear.
The right side of the car 1 means the right side of the car 1 as viewed from an elevator
hall.
[0013] A car upper frame 3 is installed on the ceiling of the car 1, and a suspending pulley
8 is mounted on the car upper frame 3. Further, a rope hitch 4 is provided on the
right side of the car 1 in the vicinity of a car floor. Also on the upper part of
the counter weight 12, a rope hitch 15 and a suspending pulley 13 are mounted. The
rope hitches 4, 15 have a function of taking up an elongation of the rope 5.
[0014] In the upper part of the elevator shaft, there are installed two first diverting
pulleys 7a, 7b whose vertical projections are substantially parallel to each other,
two second diverting pulleys 9a, 9b whose vertical projections are substantially parallel
to each other, and another second diverting pulley 9c and a third diverting pulley
14 whose vertical projections are substantially perpendicular to the vertical projections
of the second diverting pulleys 9a, 9b. The first diverting pulleys 7a, 7b, the suspending
pulley 8, a drive sheave 11 of the flat type hoist 10 and the third diverting pulley
14 are arranged so that their vertical projections are substantially parallel with
one another. The second diverting pulleys 9a, 9b are arranged so that their vertical
projections are inclined to the vertical projections of the first diverting pulleys
7a, 7b. Every diverting pulley is located above the ceiling of the car 1. Further,
the positions of the rope hitch 4, the diverting pulleys 7a, 7b and the suspending
pulley 8 are changeable because of adjusting margins provided in left and right directions
as viewed in Fig. 2, and a suspending condition of the car 1 may be adjusted during
installation thereof.
[0015] Explanation will be now made of how to wind the rope 5 in the elevator system of
the embodiment. Basically, the elevator system of the embodiment employs 3:1 roping
in which the car 1 and the counter weight 12 are suspended with the use of the rope
hitches 4, 15, and the suspending pulleys 8, 13. Specifically, as shown in Fig. 1,
at first, one end of the rope 5 is fixed to the rope hitch 4 on the right side of
the car 1 in the vicinity of the car floor, and the rope 5 is extended upward from
the rope hitch 4 and is then extended horizontally from the first diverting pulley
7a to the other diverting pulley 7b by which the rope 5 is turned downward. Further,
the rope 5 is turned upward by way of the suspending pulley 8 on the upper part of
the car 1, then is wound around the upper part of the second diverting pulley 9a,
and further, is wound around the upper part of the other second pulley 9b so as to
be turned downward. Then, the rope 5 is wound around the lower part of the further
other second diverting pulley 9c so as to be turned upward, and is then wound around
the drive sheave 11 of the flat type hoist 10 so as to be turned downward. Then, the
rope 5 is turned upward by way of the suspending pulley 13 on the upper part of the
counter weight 12 and is extended to the rope hitch 15 on the upper part of the counter
weight 12 by way of the third diverting pulley 14. The other end of the rope 5 is
fixed to this rope hitch 15.
[0016] The flat type hoist 10 is installed so that a part of its vertical projection is
positioned between the vertical projection of the car 1 and that of an elevator shaft
wall 18, and the remainder of the vertical projection of the flat type hoist 10 is
overlapped with that of the car 1. As shown in Figs. 2 and 3, the hoist is provided
therein with a motor composed of a stator 27 and a rotor 28 on the side near the elevator
shaft wall 18, and with a brake section 21 and a position detector 22 on the opposite
side of the motor with the drive sheave 11 interposed therebetween.
[0017] Further, in this embodiment, the counter weight 12 is located in the rear of the
car 1 in such a position that a part of the vertical projection of the flat type hoist
10 is overlapped with the vertical projection of the counter weight 12. Further, the
vertical projection of the gravitational center of the flat type hoist 10 is positioned
substantially between the vertical projections of the pair of guide rails 17a, 17bof
the counter weight 12, and accordingly, a load of the flat type hoist 10 may be supported
by the pair of guide rails 17a, 17b of the counter weight 12 through the intermediary
of a support member which is not shown.
[0018] As described above, according to the embodiment, because of 3:1 roping, the suspended
load is distributed to the three ropes, and accordingly, the suspended loads imparted
to the diverting pulleys are reduced, resulting in reduction of the torque of the
flat type hoist 10. That is, structural members and the flat type hoist 10 of the
elevator system 10 may be made small and thereby it can be expected is possible to
expect to reduce the manufacturing cost.
[0019] Further, with the provision of the second diverting pulleys 9a, 9b, 9c, the position
of the flat type hoist 10 may be adjusted. Thus, the position of the flat type hoist
10 is adjusted in this embodiment so that the vertical projection of the drive sheave
11 is not overlapped with that of the car 1 while the vertical projection of an end
of the brake section 21 on the side remote from the sheave 11 is located within that
of the car 1. With this configuration, the brake section 21 of the flat type hoist
10 is located facing a wide space in the elevator shaft, and accordingly, the maintenance
of the brake section 21 can be easily carried out. Similarly, as the vertical projection
of an end of the position detector 22 on the side remote from the sheave is also located
in that of the car 1, a wide space is present before the position detector 22 of the
flat type hoist 10, and accordingly, the maintenance of the position detector 22 can
be simplified. Further, work may be done near the brake section 21 and the position
detector 2, and accordingly, the maintenance work can be easy and safe in that the
worker need not lean out of the car.
[0020] Further, in the embodiment, since the vertical projection of the position detector
22 is located within that of the car 1, there is such an advantage that even though
the worker accidentally drops a component part during the servicing, the component
part may highly possibly remain on the upper part of the car 1 without dropping onto
the bottom of the elevator shaft.
[0021] Fig. 6 is a view for explaining how to wind the rope 5 in the elevator system showing
the second embodiment of the invention, Fig. 7 is a horizontal sectional view of an
elevator shaft in the elevator of this embodiment, Fig. 8 is an external view of a
hoist in the elevator system of the embodiment, Fig. 9 is a right side view of the
elevator shaft in the elevator system of the embodiment, and Fig. 10 is a front view
of the elevator shaft in the elevator of the embodiment. The elevator system of this
embodiment has a configuration basically the same as that of the first embodiment,
and explanation will be made below with a focus on differences from the first embodiment.
[0022] In this embodiment, instead of the flat type hoist 10 used in the first embodiment,
there is used a long type hoist 23. The long type hoist herein means a hoist having
a longer length in the direction of a rotation axis than a length in the direction
orthogonal to the rotational axis.
[0023] As shown in Figs. 7 and 8, a drive sheave 24 is arranged in the hoist on the side
near an elevator shaft wall 18, and a brake section 25 and a position detector 26
are provided on the opposite side from the drive sheave 24 with a motor interposed
therebetween.
[0024] According to this embodiment, technical advantages similar to those obtained in the
first embodiment can be attained concerning the maintenance work of the long type
hoist 23. Further, since not only the vertical projection of the position detector
26 but also that of the brake section 25 are positioned within the vertical projection
of the car 1, there is such an advantage that even though the worker accidentally
drops a component part during the maintenance work of the position detector 26 or
the brake section 25, the component part may highly possibly remain in the upper part
of the car 1, not dropping onto the bottom of the elevator shaft.
[0025] Fig. 11 is a front view of an elevator shaft in the elevator system showing the third
embodiment of the invention. Since the elevator system of this embodiment has a configuration
basically the same as that of the second embodiment, explanation will be made below
with a focus on differences from the second embodiment.
[0026] In this embodiment, a rope hitch 19 is provided on the lower part of a floor panel
of a car 1, and a fourth diverting pulley 20 is provided on the right end of the floor
panel of the car 1.
[0027] Next, explanation will be made of how to wind a rope 5 in the elevator system of
this embodiment. At first, one end of the rope 5 is fixed to the rope hitch 19 provided
on the lower part of the floor panel of the car 1, and the rope 5 is extended from
the rope hitch 19 upward along a side of the car 1 by way of the fourth diverting
pulley 20 provided on the end of the floor panel of the car 1 to a first diverting
pulley 7a. How to wind the rope 5 subsequently to the first diverting pulley 7a is
the same as is in the other embodiments.
[0028] According to this embodiment, technical advantages similar to those obtained in the
second embodiment can be attained. Further, since the rope hitch 19 for the rope 5
is arranged in a substantially horizontal direction, the vertical dimensions of the
rope hitch 19 can be made small even when the length of the rope hitch 19 is required
to be longer, and accordingly, it is possible to limit vertical dimensions of components
provided underneath the floor of the car 1 to the extent of the diameter of the diverting
pulley 7a. Thus, the vertical dimension of the car 1 can be decreased as compared
with that in the second embodiment, and when the elevator system is installed in the
elevator shaft of the same shape, an effective elevating stroke of the car 1 can be
ensured of being longer than that in the second embodiment. Further, in comparison
with the second embodiment, an application point of force exerted from the rope 5
to the lower part of the car 1 is divided into two positions of the rope hitch 19
and the diverting pulley 20, and thereby it is possible to effectively avoid the concentration
of the force.
[0029] It should be further understood by those skilled in the art that although the foregoing
description has been made on the embodiments of the invention, the invention is not
limited thereto and various changes and modifications may be made without departing
from the spirit of the invention and the scope of the appended claims.
1. An elevator system having a car and a counter weight suspended by a rope and driven
by a hoist, characterized by a suspending pulley provided on an upper part of the car, a rope hitch provided on
the car, a suspending pulley provided on an upper part of the counter weight, and
a rope hitch provided on the upper part of the counter weight, wherein a vertical
projection of a sheave of the hoist is not overlapped with a vertical projection of
the car, and a vertical projection of an end of a brake section of the hoist on a
side remote from the sheave is positioned within the vertical projection of the car.
2. An elevator system having a car and a counter weight suspended by a rope and driven
by a hoist, characterized by a suspending pulley provided on an upper part of the car, a rope hitch provided on
the car, a suspending pulley provided on an upper part of the counter weight and a
rope hitch provided on the upper part of the counter weight, wherein a vertical projection
of a sheave of the hoist is not overlapped with a vertical projection of the car,
and a vertical projection of an end of a position detector of the hoist on a side
remote from the sheave is positioned within the vertical projection of the car.
3. An elevator system according to claim 1 or 2, characterized in that the rope is fixed at one end thereof to the rope hitch provided on one side of the
car, the rope is extended upward from the rope hitch, is then turned downward by way
of a first diverting pulley, is turned upward by way of the suspending pulley of the
car, is wound around the sheave of the hoist by way of a second diverting pulley to
be turned downward, and is turned upward by way of the suspending pulley of the counter
weight, and the rope is fixed at another end thereof to the rope hitch of the counter
weight by way of a third diverting pulley.
4. An elevator system according to claim 1 or 2, characterized in that the rope is fixed at one end thereof to the rope hitch provided on a lower part of
a floor panel of the car, the rope is extended upward from the rope hitch by way of
a fourth diverting pulley provided on a side end part of a floor panel of the car,
is then turned downward by way of a first diverting pulley, is turned upward by way
of the suspending pulley of the car, is wound around the sheave of the hoist by way
of a second diverting pulley to be turned downward, and is turned upward by way of
the suspending pulley of the counter weight, and the rope is fixed at another end
thereof to the rope hitch of the counter weight by way of a third diverting hitch.
5. An elevator system according to any one of claims 1 to 4, characterized in the hoist is of a flat type.
6. An elevator system according to any one of claims 1 to 4, characterized in that the hoist is of a long type.