Technical Field
[0001] The present invention relates to an elevator apparatus having a drive device disposed
in an upper portion within a hoistway.
Background Art
[0002] In a conventional elevator apparatus, there is often adopted a 2:1 roping method
as to a main rope for suspending a car and a counterweight, with a view to reducing
size of a drive device. In the conventional elevator apparatus thus constructed, the
car and the counterweight are provided with a car suspending pulley and a counterweight
suspending pulley respectively. The main rope is wound around the car suspending pulley,
the counterweight suspending pulley, and a driving sheave of the drive device. The
main rope is connected at one end thereof and the other end thereof to an upper portion
of a hoistway. Thus, the axial load applied to the drive device is reduced, so the
drive device can be reduced in size (see Patent Document 1).
Disclosure of the Invention
Problem to Be Solved by the Invention
[0004] However, the rotational speed of the driving sheave is higher when the 2:1 roping
method is adopted as to the main rope than when a 1:1 roping method is adopted, so
a loud noise is made.
[0005] The present invention has been made to solve the above-mentioned problem, and it
is therefore an object of the present invention to obtain an elevator apparatus which
makes it possible to reduce the axial load applied to a drive device and abate noise.
Means for solving the Problems
[0006] An elevator apparatus according to the present invention includes: a drive device
having a drive device body and a driving sheave rotated around a vertically extending
rotational shaft by the drive device body, and disposed in an upper portion within
a hoistway; a car for being raised/lowered within the hoistway due to a driving force
of the drive device; a counterweight provided with a first counterweight rope connecting
portion and a second counterweight rope connecting portion, for being raised/lowered
within the hoistway due to a driving force of the drive device; a car suspending pulley
provided on the car; a first car side return pulley and a second car side return pulley
that are disposed in the upper portion within the hoistway and above the car; a first
counterweight side return pulley and a second counterweight side return pulley that
are disposed in the upper portion within the hoistway and above the counterweight;
and a main rope having a first rope end connected to the first counterweight rope
connecting portion and a second rope end connected to the second counterweight rope
connecting portion, and sequentially wound around the first counterweight side return
pulley, the driving sheave, the first car side return pulley, the car suspending pulley,
the second car side return pulley, and the second counterweight side return pulley
while extending from the first rope end to the second rope end, for suspending the
car and the counterweight within the hoistway.
Brief Description of the Drawings
[0007]
Fig. 1 is a lateral view showing an elevator apparatus according to Embodiment 1 of
the present invention.
Fig. 2 is a plan view showing the elevator apparatus of Fig. 1.
Fig. 3 is a plan view showing another example of the elevator apparatus according
to Embodiment 1 of the present invention.
Fig. 4 is a lateral view showing an elevator apparatus according to Embodiment 2 of
the present invention.
Fig. 5 is a lateral view showing an elevator apparatus according to Embodiment 3 of
the present invention.
Best Modes for carrying out the Invention
[0008] Preferred embodiments of the present invention will be described hereinafter with
reference to the drawings.
Embodiment 1
[0009] Fig. 1 is a lateral view showing an elevator apparatus according to Embodiment 1
of the present invention. Fig. 2 is a plan view showing the elevator apparatus of
Fig. 1. Referring to Figs. 1 and 2, a pair of vertically extending car guide rails
2 and a pair of vertically extending counterweight guide rails 3 are installed within
a hoistway 1 (Fig. 2). The respective car guide rails 2 and the respective counterweight
guide rails 3 are disposed within the hoistway 1 such that a line connecting the respective
car guide rails 2 to each other extends perpendicularly to a line connecting the respective
counterweight guide rails 3 to each other when the hoistway 1 is vertically projected.
[0010] A car 4 is disposed between the respective car guide rails 2. A counterweight 5 is
disposed between the respective counterweight guide rails 3. The car 4 is guided by
the respective car guide rails 2 to be raised/lowered within the hoistway 1. The counterweight
5 is guided by the respective counterweight guide rails 3 to be raised/lowered within
the hoistway 1. The car 4 and the counterweight 5 are disposed side by side in a width
direction of the hoistway 1 (a direction extending along the line connecting the respective
car guide rails 2 to each other) on a vertical projection plane of the hoistway 1.
In other words, the counterweight 5 is disposed beside the car 4.
[0011] A drive device 6 for generating a driving force for raising/lowering the car 4 and
the counterweight 5 is provided horizontally in an upper portion within the hoistway
1. The drive device 6 is disposed within a region of the car 4 on the vertical projection
plane of the hoistway 1. The drive device 6 has a drive device body 7, and a driving
sheave 8 which is rotated around a vertically extending rotational shaft by the drive
device body 7. In addition, the drive device 6 is designed as a low-profile hoisting
machine having a dimension in an axial direction (a direction extending along the
rotational shaft of the driving sheave 8) which is smaller than a dimension in a radial
direction (a direction extending perpendicularly to the axial direction). In this
example, the drive device 6 is disposed such that the driving sheave 8 is located
above the drive device body 7.
[0012] A pair of car suspending pulleys 9 and 10 are provided on a lower portion of the
car 4 on both sides thereof respectively. The respective car suspending pulleys 9
and 10 are disposed symmetrically with respect to a center point of a line segment
connecting the respective car guide rails 2 to each other on the vertical projection
plane of the hoistway 1 (Fig. 2).
[0013] A first car side return pulley 11 and a second car side return pulley 12 are provided
in the upper portion within the hoistway 1 and above the car 4. Each of the first
car side return pulley 11 and the second car side return pulley 12 is rotated around
a horizontally extending rotational shaft. The first car side return pulley 11 is
disposed above one of the car suspending pulleys 9. The second car side return pulley
12 is disposed above the other car suspending pulley 10.
[0014] A first counterweight rope connecting portion 13 and a second counterweight rope
connecting portion 14, which are disposed side by side in a width direction of the
counterweight 5, are provided on an upper portion of the counterweight 5. The first
counterweight rope connecting portion 13 and the second counterweight rope connecting
portion 14 are disposed on the line connecting the respective counterweight guide
rails 3 to each other on the vertical projection plane of the hoistway 1 (Fig. 2).
Further, the first counterweight rope connecting portion 13 and the second counterweight
rope connecting portion 14 are disposed symmetrically with respect to a vertical line
extending past a center of gravity of the counterweight 5.
[0015] A first counterweight side return pulley 15 and a second counterweight side return
pulley 16 are provided in the upper portion within the hoistway 1 and above the counterweight
5. Each of the first counterweight side return pulley 15 and the second counterweight
side return pulley 16 is rotated around a horizontally extending rotational shaft.
The first counterweight side return pulley 15 is disposed above the first counterweight
rope connecting portion 13. The second counterweight side return pulley 16 is disposed
above the second counterweight rope connecting portion 14.
[0016] The car 4 and the counterweight 5 are suspended within the hoistway 1 by a plurality
of main ropes 17 (only one rope is illustrated in the drawings for the sake of simplicity).
Each of the main ropes 17 has a first rope end 17a connected to the first counterweight
rope connecting portion 13, and a second rope end 17b connected to the second counterweight
rope connecting portion 14. Each of the main ropes 17, which extends from the first
rope end 17a to the second rope end 17b, is sequentially wound around the first counterweight
side return pulley 15, the driving sheave 8, the first car side return pulley 11,
the one of the car suspending pulleys 9, the other car suspending pulley 10, the second
car side return pulley 12, and the second counterweight side return pulley 16. That
is, as for the respective main ropes 17, there is adopted a 1:1 roping method in which
the moving distance of each of the main ropes 17 is equal to the moving distance of
the car 4 and the counterweight 5.
[0017] Each of the main ropes 17 is manufactured by twisting a plurality of copper wires.
Each of these wires has a wire diameter smaller than a normal wire diameter. Thus,
the respective main ropes 17 are increased in flexibility. The respective main ropes
17 may also be designed as synthetic fiber ropes to achieve further enhancement of
flexibility.
[0018] Next, an operation will be described. When the driving sheave 8 is rotated by the
drive device body 7, the respective main ropes 17 are moved in accordance with rotation
of the driving sheave 8 . Thus, the car 4 and the counterweight 5 are raised/lowered
within the hoistway 1 while being guided by the respective car guide rails 2 and the
respective counterweight guide rails 3 respectively.
[0019] Next, an axial load applied to the driving sheave 8 will be described. The car 4
and the counterweight 5 are suspended by the main ropes 17. Therefore, a first rope
tension T1 is applied to portions of the main ropes 17 which are located on the first
rope end 17a side with respect to the driving sheave 8, and a second rope tension
T2 is applied to portions of the main ropes 17 which are located on the second rope
end 17b side with respect to the driving sheave 8.
[0020] A weight W1 of the counterweight 5 is balanced with the sum of the first rope tension
T1 and the second rope tension T2. Therefore, the following equation is established.

[0021] An axial load MT applied to the driving sheave 8 is equal to the sum of the first
rope tension T1 and the second rope tension T2. Therefore, the following relationship
is established in consideration of the equation (1).

That is, the axial load MT is equal to the weight W1 of the counterweight 5.
[0022] A total weight W2 on the car 4 side (i.e. , an added weight of a car weight Wa of
the car 4 itself and a laden weight Wb of an onboard object within the car 4) is balanced
with the sum of the second rope tension T2 on the one of the car suspending pulleys
9 side and the second rope tension T2 on the other car suspending pulley 10 side.
Therefore, the second rope tension T2 is expressed by the following equation.

[0023] The first rope tension T1 is expressed by the following equation in consideration
of the equations (1) and (3).

In this example, the total weight W2 on the car 4 side is balanced with the weight
W1 of the counterweight 5 when the laden weight Wb is half of a maximum laden weight
Wbmax.
[0024] As is apparent from the equations (3) and (4), the magnitudes of the first rope tension
T1 and the second rope tension T2 may be different from each other. Accordingly, the
larger the clearance between the first counterweight rope connecting portion 13 and
the second counterweight rope connecting portion 14 becomes, the larger the offset
load applied to the counterweight 5 becomes, and the larger the reactive force applied
to each of the counterweight guide rails 3 becomes. Thus, when there is a certain
clearance between the first counterweight rope connecting portion 13 and the second
counterweight rope connecting portion 14, the level of a noise resulting from contact
of the counterweight 5 with the respective counterweight guide rails 3 may be increased,
or the life of the counterweight guide rails 3 may be shortened due to abrasion.
[0025] Accordingly, the clearance between the first counterweight rope connecting portion
13 and the second counterweight rope connecting portion 14 is set within a predetermined
range where an adverse effect resulting from an offset load applied to the counterweight
5, for example, a noise, abrasion of the counterweight guide rails 3, or the like
can be permitted. In this example, the first counterweight rope connecting portion
13 and the second counterweight rope connecting portion 14 are disposed on the counterweight
5 in close proximity to the vertical line extending past the center of gravity of
the counterweight 5.
[0026] In the elevator apparatus constructed as described above, the drive device 6 is horizontally
provided in the upper portion within the hoistway 1, and each of the main ropes 17
for suspending the car 4 and the counterweight 5 within the hoistway 1, which extends
from the first rope end 17a connected to the counterweight 5 to the second rope end
17b connected to the counterweight 5, is sequentially wound around the first counterweight
side return pulley 15, the driving sheave 8 of the drive device 6, the first car side
return pulley 11, the one of the car suspending pulleys 9, the other car suspending
pulley 10, the second car side return pulley 12, and the second counterweight side
return pulley 16. Therefore, the axial load applied to the driving sheave 8 can be
made equal to the weight of the counterweight 5, and the moving distance of the main
ropes 17 can be made directly equal to the moving distance of the car 4 and the counterweight
5. That is, both the total weight W2 on the car 4 side and the weight W1 of the counterweight
5 can be prevented from being directly applied to the driving sheave 8, and the 1:1
roping method is adopted as to the main ropes 17, so the rotational speed of the driving
sheave 8 can be reduced. Accordingly, the drive device 6 can be reduced in size, and
the space of the hoistway 1 can be reduced. Further, a noise resulting from rotation
of the driving sheave 8 can also be abated.
[0027] The respective car suspending pulleys 11 and 12 are disposed symmetrically with respect
to the center point of the line segment connecting the respective car guide rails
2 to each other on the vertical projection plane of the hoistway 1. Therefore, the
car 4 can be stably suspended by the main ropes 17.
[0028] The first counterweight rope connecting portion 13 and the second counterweight rope
connecting portion 14 are disposed symmetrically with respect to the vertical line
extending past the center of gravity of the counterweight 5, and the clearance between
the first counterweight rope connecting portion 13 and the second counterweight rope
connecting portion 14 is set within the predetermined range. Therefore, the magnitude
of an offset load applied to the counterweight 5 can be set within a permissible range.
Thus, a noise resulting from, for example, contact of the counterweight 5 on the counterweight
guide rails 3 can be abated, and the life of the counterweight guide rails 3 can be
restrained from being shortened due to abrasion.
[0029] The drive device 6 is designed as a low-profile hoisting machine having a dimension
in an axial direction which is smaller than a dimension in a radial direction, so
the dimension of the hoistway 1 in a height direction thereof can further be reduced.
[0030] In the foregoing example, the car suspending pulleys 9 and 10 are provided on the
lower portion of the car 4. However, the car suspending pulleys 9 and 10 may also
be provided on an upper portion of the car 4. In this manner as well, the car 4 can
be suspended within the hoistway 1 by the main ropes 17.
[0031] In the foregoing example, the present invention is applied to an elevator apparatus
of a counterweight-falling-sidewise type in which the counterweight 5 is disposed
beside the car 4. However, as shown in Fig. 3, the present invention may also be applied
to an elevator apparatus of counterweight-falling-behind type in which the counterweight
5 is disposed behind the car 4. In this case, the line connecting the respective car
guide rails 2 to each other is parallel to the line connecting the respective counterweight
guide rails 3 to each other on the vertical projection plane of the hoistway 1.
Embodiment 2
[0032] Fig. 4 is a lateral view showing an elevator apparatus according to Embodiment 2
of the present invention. Referring to Fig. 4, a first car rope connecting portion
21 and a second car rope connecting portion 22 are provided on the lower portion of
the car 4 on both sides thereof. The first car rope connecting portion 21 and the
second car rope connecting portion 22 are disposed symmetrically with respect to the
line segment connecting the respective car guide rails 2 to each other on the vertical
projection plane of the hoistway 1. The first car side return pulley 11 is disposed
above the first car rope connecting portion 21. The second car side return pulley
12 is disposed above the second car rope connecting portion 22.
[0033] A counterweight suspending pulley 23 is provided on the upper portion of the counterweight
5. The first counterweight side return pulley 15 and the second counterweight side
return pulley 16 are disposed above the counterweight suspending pulley 23.
[0034] The car 4 and the counterweight 5 are suspended within the hoistway 1 by the respective
main ropes 17. Each of the main ropes 17 has the first rope end 17a connected to the
first car rope connecting portion 21, and the second rope end 17b connected to the
second car rope connecting portion 22. Each of the main ropes 17, which extends from
the first rope end 17a to the second rope end 17b, is sequentially wound around the
first car side return pulley 11, the driving sheave 8, the first counterweight side
return pulley 15, the counterweight suspending pulley 23, the second counterweight
side return pulley 16, and the second car side return pulley 12. Embodiment 2 of the
present invention is identical to Embodiment 1 of the present invention in other constructional
details and other operational details.
[0035] Next, the axial load applied to the driving sheave 8 will be described. A first rope
tension T3 is applied to portions of the main ropes 17 which are located on the first
rope end 17b side with respect to the driving sheave 8, and a second rope tension
T4 is applied to portions of the main ropes 17 which are located on the second rope
end 17a side with respect to the driving sheave 8.
[0036] The total weight W2 on the car 4 side is balanced with the sum of the first rope
tension T3 and the second rope tension T4. Therefore, the following equation is established.

[0037] The axial load MT applied to the driving sheave 8 is equal to the sum of the first
rope tension T3 and the second rope tension T4. Therefore, the following relationship
is established in consideration of the equation (5).

That is, the axial load MT is equal to the total weight W2 on the car 4 side.
[0038] In the same manner as in Embodiment 1 of the present invention, the first rope tension
T3 and the second rope tension T4 are expressed by the following equations respectively.

[0039] As described above, the first car rope connecting portion 21 and the second car rope
connecting portion 22 are provided on the car 4, and the counterweight suspending
pulley 23 is provided on the counterweight 5, and each of the main ropes 17 for suspending
the car 4 and the counterweight 5, which extends from the first rope end 17a connected
to the first car rope connecting portion 21 to the second rope end 17b connected to
the second car rope connecting portion 22, is sequentially wound around the first
car side return pulley 11, the driving sheave 8, the first counterweight side return
pulley 15, the counterweight suspending pulley 23, the second counterweight side return
pulley 16, and the second car side return pulley 12. Therefore, as is the case with
Embodiment 1 of the present invention, both the total weight W2 on the car 4 side
and the weight W1 of the counterweight 5 can be prevented from being directly applied
to the driving sheave 8, and the 1:1 roping method is adopted as to the main ropes
17, so the rotational speed of the driving sheave 8 can be lowered. Thus, the axial
load applied to the drive device 6 can be reduced, and a noise can be abated.
[0040] The first rope connecting portion 21 and the second rope connecting portion 22 are
disposed symmetrically with respect to the center point of the line segment connecting
the respective car guide rails 2 to each other on the vertical projection plane of
the hoistway 1. Therefore, the car 4 can be stably suspended by the main ropes 17.
Embodiment 3
[0041] Fig. 5 is a lateral view showing an elevator apparatus according to Embodiment 3
of the present invention. Referring to Fig. 5, the first counterweight rope connecting
portion 13 and the second counterweight rope connecting portion 14, which are disposed
side by side in the width direction of the counterweight 5, are provided on the upper
portion of the counterweight 5. The car 4 and the counterweight 5 are suspended within
the hoistway 1 by a main rope body 31 having a first main rope 32 and a second main
rope 33.
[0042] The first main rope 32 has a first rope end 32a connected to the first car rope connecting
portion 21, and a second rope end 32b connected to the first counterweight rope connecting
portion 13. The first main rope 32, which extends from the first rope end 32a to the
second rope end 32b, is sequentially wound around the first car side return pulley
11, the driving sheave 8, and the first counterweight side return pulley 15.
[0043] The second main rope 33 has a third rope end 33a connected to the second car rope
connecting portion 22, and a fourth rope end 33b connected to the second counterweight
rope connecting portion 14. The second main rope 33, which extends from the third
rope end 33a to the fourth rope end 33b, is sequentially wound around the second car
side return pulley 12 and the second counterweight side return pulley 16. That is,
the second main rope 33 is wound around the second car side return pulley 12 and the
second counterweight side return pulley 16 while bypassing the driving sheave 8. Embodiment
3 of the present invention is identical to Embodiment 2 of the present invention in
other constructional details.
[0044] The main rope body 31 suspends the car 4 and the counterweight 5 such that the sum
of the weight W1 of the counterweight 5 and the total weight W2 on the car 4 side
is distributed to the first main rope 32 and the second main rope 33. The axial load
applied to the driving sheave 8 results only from a tension in the first main rope
32. That is, the axial load applied to the driving sheave 8 is equal to that part
of the sum of the weight W1 of the counterweight 5 and the total weight W2 on the
car 4 side which is borne by the first main rope 32.
[0045] As described above, the first car rope connecting portion 21 and the second car rope
connecting portion 22 are provided on the car 4, and the first counterweight rope
connecting portion 13 and the second counterweight rope connecting portion 14 are
provided on the counterweight 5. Also, the main rope body 31 for suspending the car
4 and the counterweight 5 has the first main rope 32, which is wound around the driving
sheave 8 and connected to the first car rope connecting portion 21 and the first counterweight
rope connecting portion 13, and the second main rope 33, which is connected to the
second car rope connecting portion 22 and the second counterweight rope connecting
portion 14 while bypassing the driving sheave 8. Therefore, the car 4 and the counterweight
5 can be suspended by the first main rope 32 and the second main rope 33 in a distributed
manner, so both the total weight W2 on the car 4 side and the weight W1 of the counterweight
5 can be prevented from being directly applied to the driving sheave 8. The 1:1 roping
method is adopted as to the main ropes 17, so the rotational speed of the driving
sheave 8 can be reduced. Thus, the axial load applied to the drive device 6 can be
reduced, and a noise can be abated.
[0046] In Embodiments 1 and 2 of the present invention, the present invention is applied
to the elevator apparatus of counterweight-falling-sidewise type in which the counterweight
5 is disposed beside the car 4. However, the present invention is also applicable
to an elevator apparatus of counterweight-falling-behind type in which the counterweight
5 is disposed behind the car 4.
[0047] In Embodiments 1 and 3 of the present invention, the first counterweight rope connecting
portion 13 and the second counterweight rope connecting portion 14 are disposed side
by side in the width direction of the counterweight 5. However, the first counterweight
rope connecting portion 13 and the second counterweight rope connecting portion 14
may be disposed side by side in a thickness direction of the counterweight 5. In this
case, the first counterweight rope connecting portion 13 and the second counterweight
rope connecting portion 14 are disposed symmetrically with respect to the vertical
line extending past the center of gravity of the counterweight 5. The clearance between
the first counterweight rope connecting portion 13 and the second counterweight rope
connecting portion 14 is set within a predetermined range. In this manner as well,
the magnitude of an offset load applied to the counterweight 5 can be confined within
a permissible range.
[0048] In Embodiments 1 and 3 of the present invention, the first counterweight rope connecting
portion 13 and the second counterweight rope connecting portion 14 are disposed side
by side in the width direction of the counterweight 5. However, it is also appropriate
that a plurality of (an even number of) first counterweight rope connecting portions
13 are disposed symmetrically with respect to the vertical line extending past the
center of gravity of the counterweight 5, and that a plurality of (an even number
of) second counterweight rope connecting portions 14 are disposed symmetrically with
respect to the vertical line extending past the center of gravity of the counterweight
5. In this manner, the occurrence of an offset load applied to the counterweight 5
can be prevented even when the first rope tension T1 and the second rope tension T2
are different in magnitude from each other.
1. An elevator apparatus
characterized by comprising:
a drive device having a drive device body and a driving sheave rotated around a vertically
extending rotational shaft by the drive device body, and disposed in an upper portion
within a hoistway;
a car for being raised/lowered within the hoistway due to a driving force of the drive
device;
a counterweight provided with a first counterweight rope connecting portion and a
second counterweight rope connecting portion, for being raised/lowered within the
hoistway due to a driving force of the drive device;
a car suspending pulley provided on the car;
a first car side return pulley and a second car side return pulley that are disposed
in the upper portion within the hoistway and above the car;
a first counterweight side return pulley and a second counterweight side return pulley
that are disposed in the upper portion within the hoistway and above the counterweight;
and
a main rope having a first rope end connected to the first counterweight rope connecting
portion and a second rope end connected to the second counterweight rope connecting
portion, and sequentially wound around the first counterweight side return pulley,
the driving sheave, the first car side return pulley, the car suspending pulley, the
second car side return pulley, and the second counterweight side return pulley while
extending from the first rope end to the second rope end, for suspending the car and
the counterweight within the hoistway.
2. An elevator apparatus
characterized by comprising:
a drive device having a drive device body and a driving sheave rotated around a vertically
extending rotational shaft by the drive device body, and disposed in an upper portion
within a hoistway;
a car provided with a first car rope connecting portion and a second car rope connecting
portion, for being raised/lowered within the hoistway due to a driving force of the
drive device;
a counterweight for being raised/lowered within the hoistway due to a driving force
of the drive device;
a counterweight suspending pulley provided on the counterweight;
a first car side return pulley and a second car side return pulley that are disposed
in the upper portion within the hoistway and above the car;
a first counterweight side return pulley and a second counterweight side return pulley
that are disposed in the upper portion within the hoistway and above the counterweight;
and
a main rope having a first rope end connected to the first car rope connecting portion
and a second rope end connected to the second car rope connecting portion, and sequentially
wound around the first car side return pulley, the driving sheave, the first counterweight
side return pulley, the counterweight suspending pulley, the second counterweight
side return pulley, and the second car side return pulley while extending from the
first rope end to the second rope end, for suspending the car and the counterweight
within the hoistway.
3. An elevator apparatus
characterized by comprising:
a drive device having a drive device body and a driving sheave rotated around a vertically
extending rotational shaft by the drive device body, and disposed in an upper portion
within a hoistway;
a car provided with a first car rope connecting portion and a second car rope connecting
portion, for being raised/lowered within the hoistway due to a driving force of the
drive device;
a counterweight provided with a first counterweight rope connecting portion and a
second counterweight rope connecting portion, for being raised/lowered within the
hoistway due to a driving force of the drive device;
a first car side return pulley and a second car side return pulley that are disposed
in the upper portion within the hoistway and above the car;
a first counterweight side return pulley and a second counterweight side return pulley
that are disposed in the upper portion within the hoistway and above the counterweight;
and
a main rope body having a first main rope, which includes a first rope end connected
to the first car rope connecting portion and a second rope end connected to the first
counterweight rope connecting portion and is sequentially wound around the first car
side return pulley, the driving sheave, and the first counterweight side return pulley
while extending from the first rope end to the second rope end, and a second main
rope, which includes a third rope end connected to the second car rope connecting
portion and a fourth rope end connected to the second counterweight rope connecting
portion and is sequentially wound around the second car side return pulley and the
second counterweight side return pulley while extending from the third rope end to
the fourth rope end, for suspending the car and the counterweight within the hoistway.
4. The elevator apparatus according to Claim 1,
characterized in that:
the hoistway has provided therein a pair of car guide rails for guiding the car;
the car is provided with a pair of car suspending pulleys as mentioned above; and
the respective car suspending pulleys are disposed symmetrically with respect to a
center point of a line segment connecting the respective car guide rails to each other
on a vertical projection plane of the hoistway.
5. The elevator apparatus according to Claim 2 or 3,
characterized in that:
the hoistway has provided therein a pair of car guide rails for guiding the car; and
the first car rope connecting portion and the second car rope connecting portion are
disposed symmetrically with respect to a center point of a line segment connecting
the respective car guide rails to each other on a vertical projection plane of the
hoistway.
6. The elevator apparatus according to Claim 1 or 3,
characterized in that:
the first counterweight rope connecting portion and the second counterweight rope
connecting portion are disposed symmetrically with respect to a vertical line extending
past a center of gravity of the counterweight; and
the first counterweight rope connecting portion and the second counterweight rope
connecting portion are spaced apart from each other by a clearance that is set within
a predetermined range.
7. The elevator apparatus according to Claim 1 or 3,
characterized in that:
the counterweight is provided with an even number of first counterweight rope connecting
portions as mentioned above and an even number of second counterweight rope connecting
portions as mentioned above; and
the respective first counterweight connecting portions are disposed symmetrically
with respect to a vertical line extending past a center of gravity of the counterweight;
and
the respective second counterweight connecting portions are disposed symmetrically
with respect to the vertical line.
8. The elevator apparatus according to any one of Claims 1 to 7, characterized in that the drive device is a low-profile hoisting machine having a dimension in an axial
direction along the rotational shaft which is smaller than a dimension in a radial
direction perpendicular to the rotational shaft.