JP2001077170A - Transfer device - Google Patents

Abstract

(57) [PROBLEMS] To provide a transfer device that can safely and inexpensively transfer a substrate housed in a carrier and contribute to efficient production. SOLUTION: The carrier cart, a holding member 18 supported on the carrier cart so as to be able to move up and down, a lower open type cover 20 provided on the holding member, and a substrate provided on the holding member to accommodate a substrate. The mounting device includes a mounting device 22 capable of mounting a carrier inside the cover, and a substrate pop-out preventing mechanism 24 for preventing a substrate from popping out of the carrier mounted on the mounting device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device suitable for transferring a carrier containing a substrate such as a semiconductor substrate.

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, a semiconductor substrate is accommodated in a carrier, and the carrier accommodating the substrate is transported, for example, between two semiconductor processing apparatuses or between a stocker and a semiconductor processing apparatus. The transfer device includes a transfer trolley traveling along a floor or a ceiling. The carrier accommodating the substrates is placed in a closed box so that the substrates are not contaminated during the transfer, and the closed box is attached to a transport trolley.

Further, the closed box is lifted from, for example, a stocker and lowered at a semiconductor processing section. Therefore, the transport device includes a lifting device. The lifting device is formed, for example, as a hoist including a motor and a plurality of wires (or belts). A plurality of wires are attached to the closed box, and the closed box can be raised and lowered in a horizontal posture by winding up the plurality of wires at the same time.

[0004]

SUMMARY OF THE INVENTION In a conventional transfer device,
Since the carrier accommodating the substrate was further housed in a closed box, the same number of closed boxes as the carrier was required. The closed box is expensive, larger than the carrier, and requires a large storage space when not in use.

[0005] Therefore, it has been desired that a carrier accommodating a substrate can be mounted on a transport trolley without using a closed box. However, since the carrier is not a hermetically sealed structure, there is a problem that dust adheres to the substrate during transportation. In addition, when the carrier is transported using the transport trolley, there is a possibility that the substrate accommodated in the carrier swings and the substrate jumps out of the carrier and falls from the transport trolley.

In addition, when elevating a substrate housed in a sealed box or a carrier, if there is a difference in elongation of a plurality of wires of the elevating device, there is a problem that the box or the carrier cannot be raised and lowered in a horizontal posture. If the closed box or carrier is not lifted or lowered in a horizontal position, the box or carrier will not be lowered to an accurate position, and a delivery error will occur. Therefore, it is often necessary to adjust the length of the wire.

An object of the present invention is to provide a transfer device which can transfer a substrate safely and inexpensively while being accommodated in a carrier, and can contribute to efficient production. Another object of the present invention is to provide a transport device in which an article lifted and lowered by a plurality of wires is lifted and lowered in a horizontal posture when a lifting device including a plurality of wires is provided.

[0008]

According to the present invention, there is provided a transfer apparatus, comprising: a transfer cart; a gripping member supported on the transfer cart so as to be able to move up and down; a cover having an open bottom provided on the gripping member; A mounting device provided on the member and capable of mounting a carrier accommodating a substrate in the cover, and a substrate pop-out preventing mechanism for preventing the substrate from popping out of the carrier mounted on the mounting device. Is what you do.

According to this structure, since the cover with the open bottom is provided, the substrate is not exposed to the outside of the cover, the substrate is not contaminated, and the mechanism for preventing the substrate from popping out is provided. The substrate no longer jumps out of the carrier. Therefore, the carrier accommodating the substrate can be attached to the carrier without using the sealed box.

Preferably, the carrier is a carrier that travels along a ceiling. Alternatively, the transport trolley is a transport trolley running along the floor. Preferably, the gripping member has a clean unit and can transport the carrier in a clean and isolated environment. Preferably, the substrate pop-out prevention mechanism includes a member that moves in synchronization with the vertical movement of the gripping member.

A transport device according to another aspect of the present invention includes a transport vehicle and a supported member supported on the transport vehicle by an elevating device, wherein the elevating device includes a plurality of wires, a motor, and a motor. And a wire drive mechanism for transmitting a driving force of the motor to the plurality of wires and changing a winding speed according to a winding torque of the plurality of wires.

According to this configuration, the article can be raised and lowered in a horizontal posture by the lifting device, and can be brought to a correct position. Preferably, the hoisting and lowering mechanism comprises a differential gear mechanism. Further, the hoisting / lowering mechanism includes a plurality of differential gear mechanisms.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a semiconductor manufacturing apparatus 100 according to a first embodiment of the present invention. FIG. 2 is a diagram showing the transport device 10 of FIG. The semiconductor manufacturing apparatus 100 includes, for example, a stocker 102, a plurality of semiconductor processing apparatuses 104,
6 and a transfer device 10. The stocker 102 is a part for storing a substrate such as a semiconductor wafer, for example, and the semiconductor processing devices 104 and 106 are parts for performing a known semiconductor manufacturing process on the substrate. Semiconductor processing device 10
4, 106 have, for example, an elevator device 108 for taking in and out of the substrate. The transport device 10 transports the substrate between the stocker 102 and the semiconductor processing devices 104 and 106 or between the semiconductor processing device 104 and the semiconductor processing device 106.

FIG. 7 shows a carrier 50 for accommodating a substrate 52 such as a semiconductor wafer. The carrier 50 is a container having an open front, and a plurality of substrate storage grooves 54 are provided on both sides. The substrate 52 is inserted into the substrate accommodating groove 54 and is held in the carrier 50 in a horizontal posture. FIG. 10 shows a closed box 60. The closed box 60 is formed so as to be able to store the carrier 50 (FIG. 7) that stores the substrate 52, and has a lid 62 that closes the front opening after storing the carrier 50. Therefore, the closed box 60 has an airtight structure, and is suitable for transporting the substrate 52 in a clean environment. However, the use of the closed box 60 adds additional cost to the carrier 50. The transfer device 10 according to the present invention can be applied to the carrier 5 containing the substrate 52 without using the closed box 60.
0 is adapted to be transported in a clean environment.

The transport device 10 transports a carrier 50 containing a substrate 52. The carrier 50 is transferred to the semiconductor processing device 10
4 and 106, and the semiconductor processing apparatus 10
An elevator device 108 is used for transporting the outside of the vehicle 4 and 106. The substrate 52 is a semiconductor processing device 1
After being transported to the inside of the carrier 04, 106, it is taken out of the carrier 50 and processed. When the processing on the substrate 52 is completed, the substrate 52 is stored in the carrier 50 again, and the carrier 50 is transported to the outside of the semiconductor processing devices 104 and 106 and then transported by the transport device 10.

In FIG. 1 and FIG. 2, the transfer device 10
A rail 12 extending along a ceiling, and a transport trolley 1 suspended from the rail 12 and running along the rail 12
And 4. The transport vehicle 14 includes an elevating device 16, a gripping member 18 supported on the transport vehicle 14 by the elevating device 16 so as to be able to move up and down, a lower-open cover 20 provided on the gripping member 18, a carrier mounting device 22, And a board protrusion prevention mechanism 24.

The lifting device 16 is a hoist device,
A wire drive mechanism 26 including a motor, and a wire drive mechanism 2
And a plurality of lifting wires 28 driven by the lifting wire 6. Wire drive mechanism 26 includes a motor and gear mechanism (not shown), one end of lifting wire 28 is operatively connected to a suitable gear, and the other end of lifting wire 28 is fixed to gripping member 18. You. Therefore, when the motor is operated,
The lifting wire 28 raises and lowers the gripping member 18 while maintaining a horizontal posture. Here, the term wire 28 includes a belt, a belt, a rope, and a string.

The gripping member 18 has a short, rectangular box structure, and the cover 20 hangs down from the rectangular peripheral portion of the gripping member 18 to form a box-shaped space whose lower part is opened together with the gripping member 18. Form. Carrier mounting device 2
Numeral 2 is disposed below the gripping member 18 and grips the carrier 50 containing the substrate 52 so as to be suspended. The carrier 50 accommodating the substrate 52 is covered with the grasping member 18 and the cover 20 on the upper part and the periphery thereof while being grasped by the carrier mounting device 22. Therefore, the substrate 5
The carrier 50 accommodating 2 is protected against foreign matter falling from above and foreign matter flying in the air.
In the overhead traveling type transport apparatus 10, since there are few foreign substances soaring from below, the carrier 50 accommodating the substrate 52
Is virtually completely protected from the outside environment.

Further, one side surface of the cover 20 includes a clean unit 30 for blowing clean air. The clean unit 30 includes a fan and a filter driven by a motor, and blows clean air from the clean unit 30 toward the rear part of the carrier 50 containing the substrate 52. Therefore, the inside of the cover 20 is maintained in a cleaner environment.

FIG. 3 shows the cover 2 with the gripping member 18 removed.
FIG. 2 is a plan view showing a reference numeral 0 and a carrier 50. 3 and 7
The carrier 50 has an engagement member 56 called mushroom on the upper surface. An engagement gap is formed between the upper surface of the carrier 50 and the lower surface of the engagement member 56.
FIG. 8 is a plan view showing the carrier mounting device 22 from which the gripping member 18 has been removed, and FIG. 9 is a perspective view showing the carrier mounting device 22 of FIG. The carrier mounting device 22 of the embodiment has three sets of chuck devices 32 at positions slightly outside the outer periphery of the engaging member 56 of the carrier 50. Each chuck device 32 has a vertically extending shaft 32a and a horizontal locking piece 32b attached to the shaft 32a. The shaft 32a extends upward and enters the inside of the gripping member 18, and is operatively connected to a driving means (not shown) provided inside the gripping member 18. The driving means includes a motor or an electromagnetic actuator.

In the chuck device 32, the first position where the horizontal locking piece 32b becomes parallel to the outer peripheral portion of the engaging member 56 of the carrier 50 and the horizontal locking piece 32b It is perpendicular to the outer periphery of the joining member 56 and is movable between a second position between the upper surface of the carrier 50 and the lower surface of the engaging member 56 to enter the engaging gap.
The chuck device 32 does not engage with the carrier 50 at the first position of the horizontal locking piece 32b, but engages with the carrier 50 at the second position of the horizontal locking piece 32b.

Further, FIG.
Is shown. FIG. 4 is a view showing the mechanism 24 of FIG.
FIG. 3 is a substantially vertical sectional view showing a gripping member 18 and a cover 20 including the above. FIG. 5 is a substantially vertical sectional view showing the gripping member 18 and the cover 20 in a state where the board pop-out prevention mechanism 24 is in an operating state. The substrate pop-out prevention mechanism 24 has a substrate closing plate 24a arranged so as to face the front opening of the carrier 50 (FIG. 7). The board closing plate 24a is attached to the cover 20 by a post 24b and a spring 24c. The spring 24c is arranged to pull the board closing plate 24a in the direction of the post 24b.

An upper lever arm 24d is arranged so as to be able to contact the upper surface of the carrier 50, and the upper lever arm 24d is attached to the cover 20 so as to be rotatable around a fulcrum 24e. The horizontal lever arm 24f is the substrate closing plate 24
The horizontal lever arm 24f is arranged so as to be able to contact with the upper lever arm 24d so as to be rotatable around the fulcrum 24e.

FIG. 4 shows a state before the carrier mounting device 22 is engaged with the engaging member 56 of the carrier 50. As the gripping member 18 is lowered, the upper lever arm 24d comes into contact with the upper surface of the carrier 50,
The upper lever arm 24d is pushed up by the upper surface of the carrier 50 and rotates around the fulcrum 24e. Therefore,
The horizontal lever arm 24f also rotates around the fulcrum 24e,
Press the substrate closing plate 24a. Accordingly, as shown in FIG. 5, the substrate closing plate 24a advances toward the carrier 50 against the spring 24c, and is located at the front edge of the front opening of the carrier 50. The substrate closing plate 24a is located immediately near the substrate 52 accommodated in the carrier 50. Therefore, even if the transport carriage 14 moves, the substrate 52 is prevented from jumping out of the front opening of the carrier 50.

When the gripping member 18 is raised, the upper lever arm 24d and the lateral lever arm 24f rotate in the opposite direction to that described above, and the substrate closing plate 24a is retracted by the spring 24c so as to move away from the carrier 50. .
Therefore, the carrier mounting device 22 can release the engagement of the carrier 50 with the engaging member 56 and raise the gripping member 18.

Therefore, according to the transfer apparatus of the present invention, even if the carrier 50 has a front opening, the substrate is transferred in a clean environment without jumping out of the front opening of the carrier 50. be able to. In particular, since it is not necessary to use the special closed box 60 shown in FIG. 10, it is possible to contribute to cost reduction. FIG. 6 is a diagram illustrating an example in which the carrier 50 is transferred to the inside of the semiconductor processing device 104 when the carrier 14 reaches the semiconductor processing device 104. The semiconductor processing device 104 has a carrier port 110, and the carrier port 110 is always closed by a top plate 108 a of the elevator device 108. The top plate 108 a of the elevator device 108 is arranged so as to receive the carrier 50 when the carrier 14 reaches the semiconductor processing device 104. Therefore, when the transport vehicle 14 reaches the semiconductor processing device 104, the carrier mounting device 2
2 releases the engagement of the carrier 50 with the engagement member 56, and the elevator device 108 is operated in a state where the gripping member 18 is maintained at that position (A). Then, the top plate 108a descends, and the carrier 50 descends while being placed on the top plate 108a (B). When the top plate 108a and the carrier 50 are further lowered (C), the substrate 5 is moved by an operating device (not shown).
2 is taken out of the carrier 50. A partition plate 112 closes the carrier port 110.

FIG. 11 is a plan view similar to FIG. 3 showing the cover 20 including a modification of the board pop-out prevention mechanism 24.
The board pop-out prevention mechanism 24 has two sets of vertically extending shafts 24h and horizontal locking pieces 24i attached to the shafts 24h. The horizontal locking piece 24i is arranged at a position slightly outside the front opening of the carrier 50 instead of the substrate closing plate 24a of FIG. By rotating the shaft 24h, the horizontal locking piece 24i is moved to the first position parallel to the outer peripheral portion of the carrier 50 and the second position for preventing the substrate 52 from jumping out into the front opening of the carrier 50.
It is possible to move between the positions.

FIG. 12 shows the substrate jump-out prevention mechanism 2 shown in FIG.
4 is a diagram illustrating an example of a drive mechanism of FIG. FIG. 13 shows a gripping member 18 including a driving mechanism of the board pop-out prevention mechanism 24 of FIG.
FIG. 2 is a substantially vertical cross-sectional view illustrating a cover and a cover 20. The drive mechanism of the board pop-out prevention mechanism 24 can be provided, for example, in the holding device 18. The driving mechanism includes a motor gear 24j connected to the motor 24p, and gears 24k, 24l, 24
m, 24n. One shaft 24h has a gear 24l
, And the other shaft 24h is driven by a gear 24n.

FIG. 13 is a view showing another example of the transfer device 10. As shown in FIG. The transfer device 10 includes a transfer truck 14a that travels on the floor,
A vertically movable robot arm 16a provided on the transport carriage 14a, a gripping member 18 provided on the robot arm 16a, a lower-open cover 20 provided on the gripping member 18, a carrier mounting device 22, And a prevention mechanism 24. Gripping member 18 and cover 2
0, the carrier mounting device 22, and the substrate protrusion prevention mechanism 24 are the same as those of the embodiment described with reference to FIGS. Also in this configuration, even if the carrier 50 has a front opening, the substrate can be transported in a clean environment without jumping out of the front opening of the carrier 50. In particular, since it is not necessary to use the special closed box 60 shown in FIG. 10, it is possible to contribute to cost reduction.

FIGS. 15 and 16 are views showing a transfer device 70 according to a second embodiment of the present invention. The transfer device 70 has a transfer carriage 72. The transport trolley 72 is the transport trolley 1 of the transport apparatus 10 of the semiconductor manufacturing apparatus 100 shown in FIGS.
As shown in FIG. 4, it can be hung from a rail extending along the ceiling and run along the rail. However,
The transport trolley 72 is not limited to such a transport trolley.

The carriage 72 includes an elevating device 74 and a supported member 76 supported by the elevating device 74 so as to be able to move up and down. When the transfer device 70 is used in the same manner as the transfer device 10 of the semiconductor manufacturing apparatus 100 of the previous embodiment, the supported member 76 corresponds to the holding member 18 that can hold the carrier 50 containing the substrate 52. . Alternatively, the supported member 76 may be capable of holding the closed container 60.

The lifting device 74 is a hoist device,
A wire driving mechanism 78 including a motor;
And a plurality of lifting wires 80 driven by the lifting wire 8. In FIG. 15, four wires 80 are shown. FIG.
Reference numeral 6 denotes a wire drive mechanism 78. Lifting wire 80
Is configured to raise and lower the supported member 76 while maintaining a horizontal posture.

FIG. 16 is a diagram showing details of the wire drive mechanism 78 of the lifting device 74 of FIG. Wire drive mechanism 78
Includes a differential gear mechanism 79. That is, the wire drive mechanism 78 includes a motor 82, a motor gear 83, a gear 84 engaged with the motor gear 83, and a differential case 85 fixed to the gear 84 and rotated together with the gear 84. 2
4 arranged two at a time on two orthogonal axes
Bevel gears 86a, 86b, 86c, 86d are arranged in a differential case 85, and shafts 87a, 87b, 87
c and 87d are respectively fixed to these bevel gears.
The shafts 87a and 87c are rotatably supported by the differential case 85. The shafts 87b and 87d are the differential case 85
And extends through the differential case 85. The drum 88a is attached to the end of the shaft 87b, and the drum 88b is attached to the end of the shaft 87d.

The four wires 80 (FIG. 15) are paired two by two, and one end of one set of wires 80 is connected to one drum 8.
8a, and the end of the other set of wires 80 is fixed to the other drum 88b. The other ends of these wires 80 are fixed to the supported member 76. When the motor 82 is rotated in one direction, the rotation of the motor 82 is transmitted to the differential case 85 via the gear 84, and the rotation of the differential case 85 is transmitted to the drums 88a, 88 via the shafts 87b, 87d.
b. Therefore, when the motor 82 is rotated in one direction, the drums 88a and 88b rotate, and the wire 8
0 is wound, and the supported member 76 is raised. When the motor 82 is rotated in the opposite direction, the drum 88
The wires a and 88b rotate in the opposite directions, the wire 80 is paid out, and the supported member 76 is lowered.

While the motor 82 is rotating, one of the drums 88a
Is equal to the torque applied to the other drum drum 88b, the two drums 88a and 88b rotate at the same rotation speed. However, some wires 80
, The torque applied to one drum 88a is not equal to the torque applied to the other drum drum 88b. In this case, the two bevel gears 86b and 86d rotate in opposite directions, and the two 88a, 88b
A difference occurs in the rotation speed of the motor. As a result, the rotation speed of the drum to which the stretched wire 80 is fixed becomes higher than the rotation speed of the drum to which the unstretched wire 80 is fixed. As a result, the supported member 76 rises or rises in a horizontal posture. You will be lowered. Thus, the wire driving mechanism 78 according to the present invention changes the winding speed according to the winding torque of the wire 80.

FIG. 17 is a view showing a modification of the wire drive mechanism 78 of FIG. This wire drive mechanism 78 includes two differential gear mechanisms 79a and 79b. That is, as the differential gear mechanism 79a, the wire driving mechanism 78
2, a motor gear 83, a gear 84 engaged with the motor gear 83, and a differential case 85 fixed to the gear 84 and rotated together with the gear 84. Four bevel gears (see 86a, 86b, 86c, 86d in FIG. 16) are arranged in the differential case 85, and the shaft (87a, 8 in FIG. 16).
7b, 87c, 87d) are fixed to these bevel gears, respectively. Shaft 8 of those shafts
7b and 87d are rotatably supported by the differential case 85 and extend through the differential case 85. The drum 88a is attached to the end of the shaft 87b, and the drum 88b is attached to the end of the shaft 87d. The end of one wire 80 is fixed to one drum 88a and the other is
The end of the book wire 80 is fixed to the other drum 88b.

As another differential gear mechanism 79b, a wire drive mechanism 78 includes a motor 82 and a motor gear 83
A gear 84b engaged with the motor gear 83;
b, and a differential case 85b that rotates with the gear 84b. The motor 82 and the motor gear 83 are common to those for the differential gear mechanism 79a. The motor gear 83, the gear 84, and the gear 84b are bevel gears, and are arranged such that their axes are orthogonal to each other.

Four bevel gears (86a and 86 in FIG. 16)
b, 86c, 86d) are arranged in the differential case 85, and the shafts (87a, 87b, 87c, 87 in FIG. 16).
d) are respectively fixed to these bevel gears. Of these shafts, shafts 87 b and 87 d are rotatably supported by the differential case 85 and extend through the differential case 85. The drum 88a is attached to the end of the shaft 87b, and the drum 88b is attached to the end of the shaft 87d. One end of the wire 80 is fixed to one drum 88a, and the other end of the wire 80 is fixed to the other drum 88b.

Accordingly, the winding speed of each of the four wires 80 can be changed according to the winding torque.

[0040]

As described above, according to the present invention,
The substrate can be transported safely and inexpensively while being accommodated in the carrier, which can contribute to efficient production. further,
ADVANTAGE OF THE INVENTION According to this invention, when it has a raising / lowering apparatus containing a several wire, the article lifted and lowered by a several wire is raised / lowered in a horizontal attitude | position.

[Brief description of the drawings]

FIG. 1 is a diagram showing a semiconductor manufacturing apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating the transport device of FIG. 1;

FIG. 3 is a plan view showing a cover and a carrier of the transport cart of FIGS. 1 and 2 from which a gripping member is removed.

FIG. 4 is a schematic vertical sectional view showing a gripping member and a cover including the substrate pop-out prevention mechanism of FIG. 3;

FIG. 5 is a schematic vertical sectional view showing the gripping member and the cover in a state where the board pop-out prevention mechanism is in an operating state.

FIG. 6 is a diagram illustrating an example in which a carrier is transferred to the inside of the semiconductor processing device when the carrier reaches the semiconductor processing device.

FIG. 7 is a view showing a carrier for accommodating a substrate.

FIG. 8 is a plan view showing the carrier mounting device from which the gripping member has been removed.

FIG. 9 is a perspective view showing the carrier mounting device of FIG.

FIG. 10 is a diagram illustrating an example of a closed box that stores a carrier.

FIG. 11 is a plan view showing a cover including a modification of the board pop-out prevention mechanism.

FIG. 12 is a diagram illustrating an example of a drive mechanism of the board pop-out prevention mechanism of FIG. 11;

13 is a schematic vertical sectional view showing a gripping member and a cover including a driving mechanism of the board pop-out prevention mechanism of FIG. 11;

FIG. 14 is a diagram illustrating another example of the transport device.

FIG. 15 is a view showing a transport device according to a second embodiment of the present invention.

FIG. 16 is a view showing details of a wire drive mechanism of the elevating device in FIG. 15;

FIG. 17 is a view showing a modification of the wire drive mechanism of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Transfer device 12 ... Rail 14 ... Transportation trolley 16 ... Elevating device 18 ... Grip member 20 ... Cover 22 ... Carrier mounting device 24 ... Substrate jump-out prevention mechanism 26 ... Wire drive mechanism 28 ... Wire 30 ... Clean unit 32 ... Chuck device 50 ... Carrier 52 ... Substrate 54 ... Substrate storage groove 56 ... Engaging member 70 ... Transport device 72 ... Transport cart 74 ... Elevating device 76 ... Supported member 78 ... Wire drive mechanism 79, 79a, 79b ... Differential gear mechanism 80 ... Wire

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F031 CA02 CA05 DA08 DA17 EA12 EA14 FA03 FA13 GA58 LA07 LA13 NA02 NA10

Claims (5)

[Claims] 1. A carrier, a holding member supported by the carrier so as to be able to move up and down, a lower open cover provided on the holding member, and a carrier provided on the holding member and containing a substrate. A transfer device comprising: a mounting device that can be mounted in the cover; and a substrate pop-out prevention mechanism that prevents a substrate from popping out of a carrier mounted on the mounting device. 2. The transfer device according to claim 1, wherein the gripping member has a clean unit and can transfer the carrier in a clean and isolated environment. 3. The transfer device according to claim 1, wherein the substrate pop-out prevention mechanism includes a member that moves in synchronization with the vertical movement of the holding member. 4. A transport vehicle, and a supported member supported on the transport vehicle by an elevating device, wherein the elevating device comprises:
A transport device comprising: a plurality of wires; a motor; and a wire drive mechanism that transmits a driving force of the motor to the plurality of wires and changes a winding speed according to a winding torque of the plurality of wires. 5. The transfer device according to claim 4, wherein the hoisting and lowering mechanism comprises a differential gear mechanism.