TECHNICAL FIELD
[0001] The present invention relates to a single-shaft multi-car elevator apparatus in which
a plurality of cars are raised and lowered inside a shared hoistway.
BACKGROUND ART
[0002] An elevator apparatus is disclosed in Japanese Patent Laid-Open No. SHO 59-133188,
for example, in which two cars are disposed vertically inside a shared hoistway. However,
in this elevator apparatus, since two cars and two counterweights are suspended by
two-to-one (2: 1) roping, the construction of the apparatus is complex. Furthermore,
since the rope speed and the rotational speed of the sheaves are twice those of one-to-one
(1:1) roping, noise is increased, making it impossible to operate the cars at high
speed.
DISCLOSURE OF THE INVENTION
[0003] The present invention aims to solve the above problems and an object of the present
invention is to provide an elevator apparatus enabling an upper car and a first counterweight,
and a lower car and a second counterweight, respectively, to be suspended by one-to-one
(1:1) roping, thereby enabling noise to be reduced and the upper car and the lower
car to be operated at high speed.
[0004] In order to achieve the above object, according to one aspect of the present invention,
there is provided an elevator apparatus including: a first driving machine having
a first drive sheave disposed in an upper portion of a hoistway; an upper car and
a first counterweight raised and lowered inside the hoistway by a driving force from
the first driving machine; a first main rope wound around the first drive sheave,
the first main rope having a first car end portion connected to the upper car, and
a first counterweight end portion connected to the first counterweight; a second driving
machine having a second drive sheave disposed in an upper portion of the hoistway;
a lower car having first and second lower car suspension portions, the lower car being
disposed below the upper car and raised and lowered inside the hoistway by a driving
force from the second driving machine; a second counterweight raised and lowered inside
the hoistway by a driving force from the second driving machine; a second main rope
wound around the second drive sheave, the second main rope having a second car end
portion connected to the first lower car suspension portion, and a second counterweight
end portion connected to the second counterweight; and a third main rope wound around
the second drive sheave, the third main rope having:
a third car end portion connected to the second lower car suspension portion; and
a third counterweight end portion connected to the second counterweight, wherein:
the first and second lower car suspension portions are symmetrically disposed on opposite
sides of a center of gravity of the lower car from each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005]
Figure 1 is a front elevation showing an elevator apparatus according to Embodiment
1 of the present invention;
Figure 2 is a side elevation showing the elevator apparatus in Figure 1;
Figure 3 is a plan showing the elevator apparatus in Figure 1;
Figure 4 is a front elevation showing an upper portion of a hoistway from Figure 1
enlarged;
Figure 5 is a side elevation showing the upper portion of the hoistway from Figure
1 enlarged;
Figure 6 is a plan showing an elevator apparatus according to Embodiment 2 of the
present invention; and
Figure 7 is a plan showing an elevator apparatus according to Embodiment 3 of the
present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0006] Preferred embodiments of the present invention will now be explained with reference
to the drawings.
Embodiment 1
[0007] Figure 1 is a front elevation showing an elevator apparatus according to Embodiment
1 of the present invention, Figure 2 is a side elevation showing the elevator apparatus
in Figure 1, Figure 3 is a plan showing the elevator apparatus in Figure 1, Figure
4 is a front elevation showing an upper portion of a hoistway from Figure 1 enlarged,
and Figure 5 is a side elevation showing the upper portion of the hoistway from Figure
1 enlarged. Moreover, Figure 4 is a view in the direction of arrow IV in Figure 3,
and Figure 5 is a view in the direction of arrow V in Figure 3.
[0008] In the figures, a first driving machine 3 having a first drive sheave 2 is disposed
in an upper portion of a hoistway 1. An upper car 4 and a first counterweight 5 are
raised and lowered inside the hoistway 1 by a driving force from the first driving
machine 3.
[0009] A plurality of first main ropes 6 (only one is shown in the figures) for suspending
the upper car 4 and the first counterweight 5 inside the hoistway 1 are wound around
the first drive sheave 2. The first main ropes 6 have: first car end portions 6a connected
to an upper portion of the upper car 4; and first counterweight end portions 6b connected
to an upper portion of the first counterweight 5.
[0010] The upper car 4 is suspended by the first main ropes 6 at its center of gravity.
The first counterweight 5 is also suspended by the first main ropes 6 at its center
of gravity. In addition, the upper car 4 and the first counterweight 5 are suspended
by a one-to-one (1:1) roping method.
[0011] The first driving machine 3 is disposed directly above the upper car 4 such that
an axis of rotation of the first drive sheave 2 extends horizontally. A first deflection
sheave 7 around which the first main ropes 6 are wound is disposed in an upper portion
of the hoistway 1. The first deflection sheave 7 directs the first main ropes 6 from
the first drive sheave 2 toward the first counterweight 5.
[0012] The first deflection sheave 7 is disposed such that that an axis of rotation thereof
extends parallel to the axis of rotation of the first drive sheave 2. In addition,
the first main ropes 6 are wound around the first drive sheave 2 and the first deflection
sheave 7 using a full winding method.
[0013] A second driving machine 9 having a second drive sheave 8 is disposed in an upper
portion of the hoistway 1. A lower car 10 and a second counterweight 11 are raised
and lowered inside the hoistway 1 by a driving force from the second driving machine
9. The lower car 10 is disposed below the upper car 4 inside the hoistway 1. The first
and second counterweights 5 and 11 are disposed behind the upper car 4 and the lower
car 10 inside the hoistway 1 so as to line up in a direction of frontage of the upper
car 4 and the lower car 10.
[0014] First and second lower car suspension portions 10a and 10b are disposed on first
and second side portions of an upper end of the lower car 10. The first and second
lower car suspension portions 10a and 10b are symmetrically disposed on opposite sides
of the center of gravity of the lower car 10 from each other.
[0015] A plurality of second main ropes 12 (only one is shown in the figures) and a plurality
of third main ropes 13 (only one is shown in the figures) for suspending the lower
car 10 and the second counterweight 11 inside the hoistway 1 are wound around the
second drive sheave 8.
[0016] The second main ropes 12 have: second car end portions 12a connected to the first
lower car suspension portion 10a; and second counterweight end portions 12b connected
to the second counterweight 11. The third main ropes 13 have: third car end portions
13a connected to the second lower car suspension portion 10b; and third counterweight
end portions 13b connected to the second counterweight 11.
[0017] The lower car 10 is suspended by the second and third main ropes 12 and 13 at its
center of gravity. The second counterweight 11 is also suspended by the second and
third main ropes 12 and 13 at its center of gravity. In addition, the lower car 10
and the second counterweight 11 are suspended by a one-to-one (1:1) roping method.
[0018] A second deflection sheave 14 around which the second and third main ropes 12 and
13 are wound is disposed in an upper portion of the hoistway 1. The second and third
main ropes 12 and 13 are wound around the second deflection sheave 14 using a full
winding method.
[0019] First and second guide pulleys 15 and 16 are also disposed in an upper portion of
the hoistway 1. The first guide pulley 15 is disposed directly above the first lower
car suspension portion 10a and directs the second main ropes 12 from the second drive
sheave 8 toward the first lower car suspension portion 10a. The second guide pulley
16 is disposed directly above the second lower car suspension portion 10b and directs
the third main ropes 13 toward the second lower car suspension portion 10b. The second
and third main ropes 12 and 13 pass along first and second sides of the upper car
4 so as not to interfere with the upper car 4 and are connected to the lower car suspension
portions 10a and 10b.
[0020] In addition, first and second direction-changing pulleys 17 and 18 for directing
the third main ropes 13 from the second drive sheave 8 toward the second guide pulley
16 are also disposed in an upper portion of the hoistway 1.
[0021] Axes of rotation of the second drive sheave 8, the second deflection sheave 14, and
the first guide pulley 15 extend horizontally parallel to each other. An axis of rotation
of the second guide pulley 16 extends horizontally parallel to the direction of frontage
of the upper car 4 and the lower car 10. Axes of rotation of the first and second
direction-changing pulleys 17 and 18 extend vertically.
[0022] As shown in Figure 3, a pair of car guide rails 19 for guiding raising and lowering
of the upper car 4 and the lower car 10, a pair of first counterweight guide rails
20 for guiding raising and lowering of the first counterweight 5, and a pair of second
counterweight guide rails 21 for guiding raising and lowering of the second counterweight
11 are installed inside the hoistway 1.
[0023] The car guide rails 19 are disposed such that a straight line connecting them extends
parallel to a direction of frontage of the upper car 4 and the lower car 10 and passes
through the centers of gravity of the upper car 4 and the lower car 10 in a vertical
plane of projection. Furthermore, the first lower car suspension portion 10a is disposed
closer to a front surface of the lower car 10 than the car guide rails 19 in a vertical
plane of projection, and the second lower car suspension portion 10b is disposed closer
to a rear surface of the lower car 10 than the car guide rails 19.
[0024] In an elevator apparatus of this kind, because the lower car 10 and the second counterweight
11 are suspended by second and third main ropes 12 and 13, and a first lower car suspension
portion 10a to which the second main ropes 12 are connected and a second lower car
suspension portion 10b to which the third main ropes 13 are connected are disposed
on first and second sides of the lower car 10, the upper car 4 and the lower car 10
can each be suspended by one-to-one (1:1) roping. Thus, noise from the first and second
driving machines 3 and 9 is reduced, enabling the upper car 4 and the lower car 10
to be operated at high speed.
[0025] Because the first and second lower car suspension portions 10a and 10b are symmetrically
disposed on opposite sides of the center of gravity of the lower car 10 from each
other, the upper car 4 and the lower car 10 can each be suspended at positions of
their centers of gravity, thereby preventing eccentric loads from acting on the upper
car 4 and the lower car 10, and enabling the upper car 4 and the lower car 10 to be
operated stably.
[0026] In addition, because the first guide pulley 15 is disposed directly above the first
lower car suspension portion 10a, and the second guide pulley 16 was disposed directly
above the second lower car suspension portion 10b, the second and third main ropes
12 and 13 can be directed to the first and second lower car suspension portions 10a
and 10b by a simple construction, enabling the upper car 4 and the lower car 10 to
be operated stably.
[0027] Furthermore, because direction-changing pulleys 17 and 18 are used to direct the
third main ropes 13 from the second drive sheave 8 to toward the second guide pulley
16, the third main ropes 13 can be prevented from interfering with the first driving
machine 3 by a simple construction.
[0028] Because the first and second counterweights 5 and 11 are disposed behind the upper
car 4 and the lower car 10 inside the hoistway 1 so as to line up in a direction of
frontage of the upper car 4 and the lower car 10, space inside the hoistway 1 can
be used effectively, enabling frontage dimensions of the hoistway 1 to be reduced.
Embodiment 2
[0029] Next, Figure 6 is a plan showing an elevator apparatus according to Embodiment 2
of the present invention. In Embodiment 1, the first and second counterweights 5 and
11 are disposed behind the upper car 4 and the lower car 10, but as shown in Figure
6, the first and second counterweights 5 and 11 may also be disposed beside the upper
car 4 and the lower car 10 inside the hoistway 1.
[0030] In an elevator apparatus of this kind, because the first and second counterweights
5 and 11 are disposed beside the upper car 4 and the lower car 10 inside the hoistway
1 so as to line up in a depth direction of the upper car 4 and the lower car 10, space
inside the hoistway 1 can be used effectively, enabling depth dimensions of the hoistway
1 to be reduced.
Embodiment 3
[0031] Next, Figure 7 is a plan showing an elevator apparatus according to Embodiment 3
of the present invention. In Embodiment 1, the car guide rails 19 are disposed at
an intermediate portion in a depth direction of the upper car 4 and the lower car
10, but because eccentric loads will not act on the car guide rails 19 if the upper
car 4 and the lower car 10 are suspended at their center of gravity, the position
of installation of the car guide rails is not limited to that of Figure 3.
[0032] Consequently, as shown in Figure 7, for example, the lower car the suspension portions
10a and 10b may also be disposed at an intermediate portion in the depth direction
of the lower car 10, and the car guide rails 19 disposed in a vicinity of corner portions
in symmetrical positions relative to the centers of gravity of the upper car 4 and
the lower car 10. In that case, the guide pulleys 15 and the direction-changing pulleys
18 in Figure 3 can be omitted, enabling the layout to be simplified.
[0033] Moreover, the driving machines 3 and 9, the deflection sheaves 7 and 14, the guide
pulleys 15 and 16, and the direction-changing pulleys 17 and 18 may also be disposed
in a machine room positioned in an upper portion of the hoistway 1, or they may also
be disposed in an upper portion inside the hoistway 1. In other words, the present
invention can be applied both to elevator apparatuses having a machine room, and to
machine-roomless elevators.
[0034] Furthermore, in the above examples, the driving machines 3 and 9 are disposed such
that the axes of rotation of the drive sheaves 2 and 8 extend horizontally, but driving
machines may also be disposed such that axes of rotation of drive sheaves extend vertically.
[0035] In addition, in the above examples, one or two direction-changing pulleys are used,
but three or more may also be used in order to avoid interference between the third
main ropes and other equipment in the upper portion of the hoistway.
[0036] Furthermore, in the above examples, the main ropes are wound around the drive sheaves
and the deflection sheaves by a full winding method, but a half winding method may
also be used provided that sufficient traction can be provided. The deflection sheaves
may also be omitted provided that sufficient traction can be provided.
1. An elevator apparatus comprising:
a first driving machine having a first drive sheave disposed in an upper portion of
a hoistway;
an upper car and a first counterweight raised and lowered inside the hoistway by a
driving force from the first driving machine;
a first main rope wound around the first drive sheave, the first main rope having
a first car end portion connected to the upper car, and a first counterweight end
portion connected to the first counterweight;
a second driving machine having a second drive sheave disposed in an upper portion
of the hoistway;
a lower car having first and second lower car suspension portions, the lower car being
disposed below the upper car and raised and lowered inside the hoistway by a driving
force from the second driving machine;
a second counterweight raised and lowered inside the hoistway by a driving force from
the second driving machine;
a second main rope wound around the second drive sheave, the second main rope having
a second car end portion connected to the first lower car suspension portion, and
a second counterweight end portion connected to the second counterweight; and
a third main rope wound around the second drive sheave, the third main rope having
a third car end portion connected to the second lower car suspension portion, and
a third counterweight end portion connected to the second counterweight,
wherein the first and second lower car suspension portions are symmetrically disposed
on opposite sides of a center of gravity of the lower car from each other.
2. The elevator apparatus according to Claim 1, wherein:
a first guide pulley for directing the second main rope toward the first lower car
suspension portion is disposed in an upper portion of the hoistway directly above
the first lower car suspension portion; and
a second guide pulley for directing the third main rope toward the second lower car
suspension portion is disposed in an upper portion of the hoistway directly above
the second lower car suspension portion.
3. The elevator apparatus according to Claim 1, wherein:
a guide pulley for directing the third main rope toward the second lower car suspension
portion is disposed in an upper portion of the hoistway directly above the second
lower car suspension portion; and
a direction-changing pulley for directing the third main rope from the second drive
sheave toward the guide pulley is disposed in an upper portion of the hoistway.
4. The elevator apparatus according to Claim 1, wherein the first and second counterweights
are disposed behind the upper car and the lower car inside the hoistway so as to line
up in a direction of frontage of the upper car and the lower car.
5. The elevator apparatus according to Claim 1, wherein the first and second counterweights
are disposed beside the upper car and the lower car inside the hoistway so as to line
up in a depth direction of the upper car and the lower car.