JPH11348775A - Carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a slip of a device in a steep ascending/descending road without causing a slip, shortening the life of a wheel, and worsening a riding feeling, even the difference of rotation frequency occurs between right and left wheels during travel on a curved road. SOLUTION: In a vehicle 1 carrying device for traveling sharply curved or steeply ascending/descending roads, a pin rack 5 is laid along a wheel tread 4 in only steep or sharply curved parts incapable of wheel travel. A pinion 6e for engaging with the pin rack 5 is arranged in one side of wheel units 6 and 7 to be installed at given intervals in a frame 8 fitted by the vehicle 1. Wheels 6a and 7a are fitted so as to be integrally rotatable to axles 6b and 7b pivotally mounted on fore and rear wheel units 6 and 7 so as to be rotatable respectively. Pinions 6d and 7d and the wheels 6a and 7a are driven via a differential gearing 10 by a motor 11, consequently the vehicle can be smoothly and quietly carried.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for transporting vehicles in an amusement park which travels on a flat part from a steep slope with a sharp curve, and transport containers in a production line, a mountain area, a warehouse, and the like.

[0002]

2. Description of the Related Art For example, in an excursion vehicle mainly composed of shows,
In order to taste the thrill, visual and auditory appeal to the visitors, the vehicle may be accelerated or decelerated by traveling on a steep curved road to apply lateral gravitational acceleration or traveling on a steep hoistway. ing.

[0003] In such a pleasure car, it is necessary to eliminate the difference in the rotational speeds of the left and right wheels while traveling on a curved road, and to prevent slipping on a steep hoistway. In addition, it is necessary to improve ride comfort.

[0004]

As a transporting device having the above-described functions and functions, there is a transporting device which is self-propelled by frictional resistance of wheels. However, in the case of electrically controlling the rotation speed of the left and right wheels in a self-propelled transport device, a power source is provided for each wheel, and thus there is a problem that the control device becomes complicated. In addition, when projections are provided on the running surface to improve the frictional resistance with the wheels on the hoistway in order to prevent slipping on a steep hoistway, the life of the wheels is shortened and the riding comfort is reduced. There is also a problem that it becomes worse.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems. In a self-propelled transportation device, even if a difference in the number of rotations occurs between the left and right wheels during traveling on a curved road, slippage is prevented. It is an object of the present invention to provide a transportation device that can prevent slipping on a steep hoistway without causing generation of a wheel, shortening the life of wheels, and deteriorating riding comfort.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, a transport device according to the present invention provides a rack or chain along a traveling rail only on a steep part or a steep part where wheels cannot travel. A pinion or a sprocket that meshes with the rack or the chain is arranged on at least one of the wheel units installed at a predetermined interval on the frame to which the vehicle is attached while being laid, and each is rotatable. The wheels are mounted on an axle pivotally connected to the front and rear wheel units so that the wheels can be integrally rotated, and the pinion or sprocket and the wheels are driven from a drive source via a differential gear device. By doing so, the vehicle can be smoothly transported by a rack and a pinion or a chain and a sprocket on a steep curved road or a steep hoistway, and by other wheels by a wheel.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A transportation device of the present invention is a device for transporting a vehicle traveling on a steep curved road or a steep hoistway. A rack or chain is laid along a running rail or a wheel tread surface, and a pinion or sprocket meshes with the rack or chain on at least one of wheel units installed at a predetermined interval on a frame to which the vehicle is attached. Are mounted, and the wheels are attached to an axle pivotally connected to the front and rear wheel units so that each can rotate freely, and the pinion or sprocket and the wheels are driven from a drive source. It is configured to be driven via a differential gear device, and if necessary, transmits power only in the traveling direction, along the power transmission path from the drive source to the wheels. Or interposed a free rotation clutch that, also in the middle of a power transmission path from the driving source to the wheels,
A free rotation clutch that transmits power only in the direction opposite to the free rotation clutch described above, and a clutch that turns on and off the transmission of power to the free rotation clutch,
In addition, the front and rear wheel units are pivotally supported on a frame so as to be rotatable on the axis of each axle or on an extension of the axis and about the center in the width direction of the wheel unit as a rotation center. A guide roller for guiding the movement of the wheel unit along the traveling rail or the wheel tread surface is provided, and another power source is arranged in the differential gear device separately from the drive source.

According to the conveying device of the present invention, the rotational force of the drive source is transmitted to the pinion or the sprocket via the differential gear device.
By transmitting to the wheels and the wheels, the steep range can be driven by the rack and the pinion or the chain and the sprocket, and the flat portion and the range that can be driven by the frictional resistance of the wheels can be set to the wheel running. At this time, since a differential gear device is interposed between the left and right wheels, a slip occurs between the left and right wheels and the running rail or the wheel tread even if a difference in rotation speed occurs between the left and right wheels while traveling on a curved road. I will not do it.

If a free-rotating clutch for transmitting power only in the running direction is provided in the middle of the power transmission path from the drive source to the wheels, the wheels will wear and the pitch circle diameter of the pinion or sprocket and the wheel diameter will be reduced. If there is a difference in the outer diameter, or if the number of rotations of the wheels becomes larger than the number of rotations of the pinion or the sprocket during traveling, the wheels are in a state of so-called free rotation and do not slip. .

A free-rotation clutch for transmitting power only in a direction opposite to the above-mentioned free-rotation clutch in the middle of a power transmission path from the drive source to the wheels, and turning on and off the transmission of power to the free-rotation clutch. If a clutch that turns off is provided, traveling in the reverse direction is also possible. At this time, when the wheel wears and a difference occurs between the pitch circle diameter of the pinion or the sprocket and the outer diameter of the wheel, or during traveling, even when the rotation speed of the wheel becomes larger than the rotation speed of the pinion or the sprocket, The wheels are in a so-called free-rotating state and do not slip.

In addition, the front and rear wheel units are pivotally supported on a frame so as to be rotatable about the axis of each axle or an extension of the axis and about the center in the width direction of the wheel unit. When the wheel unit is provided with a guide roller for guiding the movement of the wheel unit along the running rail or the wheel tread, the pinion or sprocket is always tangent to the curve of the rack or chain, even on a sharp curve. As a result, the pinion can be smoothly engaged with the rack or the sprocket and the chain.

[0012] In addition to the drive source,
By arranging another power source, when the drive source fails, the vehicle can be safely transported to a horizontal place using the other power source.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a transportation device according to the present invention; FIG. FIG. 1 is a plan view showing an embodiment of the transport device of the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a view taken along the line AA of FIG. 1, and FIG. FIG. 5 is a plan view showing an example of a traveling path, FIG. 5 is a side view of FIG. 4, and FIG.
1 is an enlarged view showing the vicinity of a free-rotation clutch in a power transmission mechanism from a drive unit of the embodiment shown in FIG. 1, (a) is a cross-sectional front view, and (b) is an arrow B in (a). -B diagram,
(C) is a view taken along the line CC of (a), and FIGS. 7 to 9 are views showing another embodiment of the transport device of the present invention.

In FIG. 1 to FIG. 3, reference numeral 1 denotes a vehicle, and the vehicle 1 is provided with a transportation device of the present invention having a structure described below, for example, as shown in FIGS. Even on the traveling rail 2 having a graded hoistway, it is transported smoothly and quietly.

Reference numeral 3 denotes a support beam supported by a pillar (not shown) from the ground or the frame of the building. In the embodiment shown in FIGS. 1 to 3, a wheel tread 4 instead of the running rail 2 is connected to the support beam 3. ing. A pin rack 5 is laid along the wheel tread 4 (the running rail 2 in FIG. 4), for example, on the back side of the wheel tread 4 on the steep slope portion or the sharp curve portion of the support beam 3.

Reference numerals 6 and 7 denote front and rear wheel units having left and right two pairs of wheels 6a and 7a rolling on the wheel tread surface 4, respectively. Installed at intervals.

The wheel units 6 and 7 are rotatably supported via bearings 6c and 7c, respectively.
Gears 9a for transmitting power from the wheels 6a, 7a and a drive source 11 described later to the wheels 6a, 7a are attached to the wheels 6b, 7b so as to rotate integrally with the axles 6b, 7b.

The wheel treads 4 of the axles 6b, 7b
The shafts 6d and 7d are rotatably supported via bearings 6h and 7i at a lower position with the shaft 6d and 7d therebetween.
The side gear 10a of the differential gear device 10 has shafts 6d and 7
It is keyed so as to rotate integrally with d.

A pinion 6e meshing with the pin rack 5 and a motor 11 serving as a driving source are provided on an outer frame 10b of the differential gear device 10 installed on one wheel unit 6.
A bevel gear 12b meshing with a bevel gear 12a attached to the output shaft 11a is fixed. The electric power of the motor 11 is supplied, for example, from an electric wire (not shown) laid in parallel on the wheel tread surface 4.

In the other wheel unit 7, a gear 7e is mounted on an outer frame 10b of the differential gear device 10, and a pinion 13 mounted on an output shaft of a motor 11 as a driving source is engaged with the gear 7e. ing.

Therefore, the rotation of the output shaft 11a of the motor 11 is controlled by the bevel gear 12a from the bevel gear 12a in the wheel unit 6.
b to the outer frame 10b of the differential gear device 10, that is, the pinion 6e. In addition, the rotation of the output shaft 11a of the motor 11 is controlled by the bevel gear 12a through the bevel gear 12b in the wheel unit 6, the pinion 13 through the gear 7e in the wheel unit 7, and the differential gear from the outer frame 10b in the wheel unit 7. Via the pinion 10c of the device 10, the side gear 10
a, that is, transmitted to the shafts 6d and 7d.
From the gear 9b mounted so as to rotate integrally with 7d, it is also transmitted to the wheels 6a, 7a via the gear 9a meshing with the gear 9b.

Therefore, in the steep part or the steep part where the pin rack 5 is laid, the pinion 6
e is engaged with the pin rack 5, and the vehicle 1 is connected to the wheels 6a and 7a.
Through the wheel tread surface 4. On the other hand, a flat portion where the pin rack 5 is not laid or a range in which the vehicle can travel due to frictional resistance of the wheels is transported along the wheel tread surface 4 by driving the wheels 6a and 7a.

Meanwhile, in one wheel unit 6, both the pinion 6e and the wheel 6a are connected to the same motor 11. Therefore, when shifting from wheel drive to pinion drive, for example, if the outer diameter of the wheel 6a is worn or there is a difference between the outer diameter of the wheel 6a and the pitch circle diameter of the pinion 6e, slip occurs. I do.

Therefore, in this embodiment, a free-rotation clutch 14 for transmitting power only in the traveling direction (rightward on the paper in FIG. 1) is provided on the gear 9b. By providing the free rotation clutch 14 in this manner, when the vehicle is driven by wheel drive or pinion drive, that is, when the shaft 6d rotates clockwise as indicated by an arrow in FIG.
The cam 14a of the second gear bites into the gap between the claws 14b, and the rotational force is transmitted to the gear 9b.

When the vehicle is driven by the pinion drive, for example, on a steep descent, the pinion 6
e, the number of revolutions of the wheel 6a increases, and the gear 9b
It rotates faster than d. In such a case, if the free rotation clutch 14 is interposed, the cam 14a rotates faster than the claw 14b, so that the cam 14a and the claw 14b do not engage, and the wheel 6a rotates freely and slips. Can be prevented.

In this embodiment, a free rotation clutch 15 for transmitting power only in a direction opposite to the running direction (left direction in FIG. 1) is provided on the opposite side of the free rotation clutch 14 of the gear 9b. A clutch 16 for turning on and off the transmission of power to the free rotation clutch 15 is provided.

In this way, when the clutch 16 is turned on by, for example, an electromagnet (not shown) against the urging force of the spring 17, the shaft 6d is turned in a counterclockwise direction indicated by an arrow in FIG. 6B. When rotated, the cam 15a of the free rotation clutch 15 bites into the gap between the claws 15b, and the rotational force is transmitted to the gear 9b, so that the vehicle 1 is transported in the direction opposite to the traveling direction.

When traveling in the opposite direction by pinion drive,
If the wheel 6a is worn and the pitch circle diameter of the pinion 6e is different from the outer diameter of the wheel 6a, or if the rotation speed of the wheel 6a becomes larger than the rotation speed of the pinion 6e during running, free rotation is performed. Since the cam 15a of the clutch 15 rotates faster than the pawl 15b, the cam 15a and the pawl 15b do not engage,
The wheels 6a are free to rotate, so that slip can be prevented.

The wheel units 6 and 7 are provided with bearings such that they can rotate about the center of the wheel units 6 and 7 in the width direction, for example, on the extension of the axis of the axles 6b and 7b. 18 attached to the frame 8.

In addition, arms 6f, 7f protrude from the left and right sides of the wheel units 6, 7, respectively.
In addition, for example, two guide rollers 6 g and 7 g for guiding the side wall of the support member 3 are provided in the front-rear direction of the wheel units 6 and 7, for example. The guide rollers 6g and 7g
Since it is only necessary to be able to guide the movement of the wheel units 6 and 7 along the wheel tread 4, the guide may guide the vicinity of the pin rack 5 or the wheel tread 4.

The transport device of the present invention has the above-described configuration,
When the motor 11 is driven, in the wheel unit 6, the rotational force is transmitted to the outer frame 10b of the differential gear device 10, that is, the pinion 6e via the output shaft 11a, the bevel gear 12a, and the bevel gear 12b. 6e is rotated. In addition, the rotational force of the motor 11 is applied to the outer frame 1 of the differential gear device 10.
0b through the pinion 10c of the differential gear device 10,
From the side gear 10a, that is, the gear 9b, which is transmitted to the shaft 6d and is mounted so as to rotate integrally with the shaft 6d, is transmitted to the wheel 6a via the gear 9a meshing with the gear 9b, and is transmitted to the pinion 6e. 6a in the same direction as
To rotate.

In the wheel unit 7, the rotational force is transmitted through the pinion 13 and the gear 7e to the differential gear device 10
From the outer frame 10b of the differential gear device 10 via a pinion 10c to the side gear 10a, that is, the shaft 9d, and from the gear 9b attached to rotate integrally with the shaft 7d, meshes with the gear 9b. Is transmitted to the wheel 7a via the gear 9a to rotate the wheel 7a in the same direction as the pinion 6e.

Therefore, the vehicle 1 is transported on the steeply sloping portion or the steeply curved portion where the pin rack 5 is laid, by the engagement of the pinion 6e with the pin rack 5.
On the other hand, since the pin rack 5 is not laid in the flat portion or the range where the vehicle can travel due to the frictional resistance of the wheels, the wheels are transported by the rotation of the wheels 6a and 7a.

At this time, since the differential gear device 10 is interposed between the left and right wheels 6a and 7a in the transport device of the present invention, the difference in the rotational speed between the left and right wheels 6a and 7a during traveling on a curved road. Does not occur with the wheel tread 4.

Further, in the transport device of the present invention, since the free rotation clutch 14 is provided on the gear 9b, the cam 14a of the free rotation clutch 14 fits in the gap between the claws 14b during the traveling by the wheel drive or the pinion drive. Thus, the rotational force is transmitted to the gear 9b. Then, when traveling by the pinion drive, the rotation speed of the wheel 6a becomes larger than that of the pinion 6e, and when the gear 9b rotates faster than the shaft 6d, the cam 14a rotates faster than the claw 14b.
Since the cam 14a and the claw 14b are not engaged, the wheel 6a rotates freely and does not slip.

Further, in the transport device of the present invention, the gear 9b
The free rotation clutch 15 and the clutch 16 are interposed on the side opposite to the free rotation clutch 14. Therefore, when the clutch 16 is turned on and the shaft 6d is rotated in the opposite direction, the cam of the free rotation clutch 15 The rotation force is transmitted to the gear 9b by the engagement of the gear 15a into the gap between the claws 15b, and the vehicle 1 is transported in the opposite direction.

If the rotation speed of the wheel 6a is higher than the rotation speed of the pinion 6e during traveling in the opposite direction by the pinion drive, the cam 15a of the free rotation clutch 15 is moved from the pawl 15b in the same manner as described above. Rotating fast, cam 1
Since the hook 5a does not engage with the claw 15b, the wheel 6a freely rotates and does not slip.

When the vehicle travels in the opposite direction only on the flat part, the free rotation clutch 15,
Even if the clutch 16 or the like is not mounted, it is sufficient to allow the wheel unit 7 to run the vehicle in the opposite direction.

In the transport device of the present invention, the wheel units 6 and 7 rotate on the extension of the axis of the axles 6b and 7b, and rotate about the center of the wheel units 6 and 7 in the width direction. Guide rollers 6g and 7g are attached to the frame 8 via bearings 18 on the left and right sides of the wheel units 6 and 7 to guide the inside of the wheel tread 4 as possible.
Are provided two each before and after the wheel units 6 and 7, even on a steep curved road, the pinion 6e is always tangential to the curve of the pin rack 5 as shown in FIG. The pinion 6e and the pin rack 5 can be smoothly engaged with each other.

It goes without saying that the transport device of the present invention is not limited to the above embodiment. For example, in this embodiment, the pinion 6e is attached to only one wheel unit 6, but the pinion may be attached to the other wheel unit 7.

Further, as shown in FIG.
And the wheel unit 7 may be driven by one motor 11. However, in this case, it is necessary to install a differential gear device 19 that absorbs the difference in rotation speed between the wheels 6a and 7a of the wheel unit 6 and the wheel unit 7. Note that 2 in FIG.
0 is a pinion keyed to the output shaft 11a of the motor 11,
21 is a differential gear device 1 for meshing with the pinion 20.
A gear 22 mounted on the outer frame 9 is connected to the output shaft 19a of the differential gear device 19, and a power transmission shaft for transmitting rotational force to the wheel units 6, 7, and 7h is a pinion of the wheel unit 7.

When the wheel unit 6 and the wheel unit 7 are driven by one motor 11 as shown in FIG. 7, the pinion 6e (7h) of one of the front and rear wheel units 6 (7) is damaged. In this case, for example, the power transmission shaft 22 on the output shaft 19a side of the broken differential gear device 19
Is fixed, and if the damaged pinion 6e (7h) is removed,
The motor 1 from the undamaged vehicle unit 7 (6)
The power transmission unit up to 1 serves as a load, and the vehicle 1 can be safely lowered by its own weight to a horizontal place.

The wheel unit 6 shown in FIG.
In the case where the wheel unit 7 is driven by one motor 11, if the emergency power source 23 is provided, when the motor 11 fails, the emergency power source 23 is used. The vehicle 1 can be safely transported to a horizontal place.

In the embodiment shown in FIGS. 1 to 3, the support beam 3 and the wheel tread surface 4 are connected to each other.
As shown in FIG. 8, the traveling rail 2 may be attached to a support member 3a provided on the support beam 3.

Further, the transport device of the present invention is not limited to the above-described embodiment, but may be one as shown in FIG. This figure 9
Is mounted on an axle 26 rotatably mounted on a carriage 24 via a bearing 25 so that wheels 27 are mounted so as to rotate integrally with the axle 26, and the wheels 27 are rotated by the motor 11. Is what you do.

That is, in the transporting apparatus shown in FIG. 9, a gear 28 meshing with the pinion 13 attached to the output shaft of the motor 11 is attached to one of the clutches 29a. Pinion 13, gear 2
8, one of the clutches 29 in the OFF state shown in FIG.
This is transmitted to the axle 26 via 9a, the wheels 27 are rotated, and the bogie 24 travels.

When the pinion 5 attached to the other side 29b of the clutch 29 engages with the pin rack 5 laid along the traveling rail 2 at a steep slope, the clutch 29 is turned on (the state shown in FIG. 9). (In a state in which one of the clutches 29a is moved to the right side in the drawing), the rotational force of the motor 11 is reduced by the pinion 13, the gear 28,
The cart 24 is run by rotating the pinion 30 via the other 29b of the clutch 29 in the ON state. At the time of this pinion drive, the integral connection between the one axle 29a of the clutch 29 and the axle 26 is released, the torque of the motor 11 is not transmitted to the axle 26, and the wheels 27 rotate freely, so that no slip occurs.

In this embodiment, the pin rack 5 and the pinions 6d, 7d are used. However, for example, a roller chain and a sprocket may be used. Further, in the present embodiment, the vehicle 1 is fixed to the frame 8, but may be supported via a cushioning material.

[0049]

As described above, in the transportation device of the present invention, the rotational force of the drive source is transmitted to the pinion or sprocket and the wheels via the differential gear device, so that the range of the steep slope can be reduced. And a pinion, or a chain and a sprocket, and a range in which the vehicle can travel by a flat portion or frictional resistance of wheels can be wheel traveling. At this time, since a differential gear device is interposed between the left and right wheels, even if a difference in the number of rotations occurs between the left and right wheels while traveling on a curved road, a slip with the traveling rail does not occur. Absent. Therefore, according to the transport device of the present invention, the vehicle can be transported smoothly and quietly.

Further, in the carrying device of the present invention, if a free-rotating clutch for transmitting power only in the traveling direction is provided in the middle of the power transmission path from the drive source to the wheels, the wheels are worn and the pinion or sprocket is worn. If there is a difference between the pitch circle diameter of the wheel and the outer diameter of the wheel, or if the rotation speed of the wheel becomes greater than the rotation speed of the pinion or sprocket during traveling, the wheel will be in a state of so-called free rotation. So you won't slip.

Further, in the transport device of the present invention, a free-rotating clutch that transmits power only in the direction opposite to the above-described free-rotating clutch in the middle of a power transmission path from the drive source to the wheels, O power transmission
If a clutch that turns N and OFF is provided, traveling in the reverse direction is also possible. And, at this time, when the wheel wears and a difference occurs between the pitch circle diameter of the pinion or the sprocket and the outer diameter of the wheel, or when the running speed of the wheel becomes larger than the rotating speed of the pinion or the sprocket. In this case, the wheels are in a state of free rotation, so that the wheels do not slip.

Further, in the transporting device of the present invention, the front and rear wheel units are arranged on the axis of each axle or an extension of the axis and with the center in the width direction of the wheel unit as the center of rotation.
When pivotally supported on the frame so as to be able to rotate, and the wheel unit is provided with a guide roller that guides the movement of the wheel unit along the traveling rail or the wheel tread, even on a steep curved road, Since the pinion or sprocket always meshes tangentially with the curve of the rack or chain, the pinion and rack or sprocket can smoothly mesh with the chain.

Further, in the carrying device of the present invention, if another power source is arranged in the differential gear device in addition to the drive source,
When the drive source fails, the vehicle can be safely transported to a horizontal place using another power source.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a transport device of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a view taken in the direction of arrows AA in FIG. 1;

FIG. 4 is a plan view showing an example of a traveling path on which the transport device of the present invention travels.

FIG. 5 is a side view of FIG. 4;

6 is an enlarged view showing the vicinity of a free-rotation clutch in a power transmission mechanism from a drive unit of the embodiment shown in FIG. 1;
(A) is a cross-sectional front view, and (b) is a view B in (a).
FIG. 3B is a view taken along the line CC in FIG.

FIG. 7 is a schematic plan view showing another embodiment of the transport device of the present invention.

FIG. 8 is a view similar to FIG. 3, showing another embodiment of the transport device of the present invention.

FIG. 9 is a view similar to FIG. 3, showing another embodiment of the transport device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle 2 Running rail 4 Wheel tread 5 Pin rack 6 Wheel unit 6a Wheel 6b Axle 6c Bearing 6e Pinion 6g Guide roller 7 Wheel unit 7a Wheel 7b Axle 7c Bearing 7g Guide roller 8 Frame 10 Differential gear device 11 Motor 14 Free rotation clutch 15 Free rotation clutch 16 Clutch 18 Bearing 23 Power source

Claims (5)

[Claims] An apparatus for transporting a vehicle traveling on a steeply curved road or a steep hoistway, wherein a rack is provided along a traveling rail or a wheel tread only on a steeply curved portion or a steeply curved portion where wheel traveling is impossible. Or, while laying a chain, a pinion or a sprocket that meshes with the rack or the chain is arranged on at least one of the wheel units installed at a predetermined interval on the frame on which the vehicle is mounted, and The wheels are mounted on the axle pivotally attached to the front and rear wheel units so as to be rotatable so as to be integrally rotatable, and the pinion or sprocket and the wheels are driven from a drive source via a differential gear device. A transport device characterized by being configured as described above. 2. The transport device according to claim 1, wherein a free-rotating clutch for transmitting power only in the traveling direction is provided in the power transmission path from the drive source to the wheels. 3. A free-rotation clutch for transmitting power only in a direction opposite to the free-rotation clutch according to claim 2 in a power transmission path from a drive source to wheels, and a transmission of power to the free-rotation clutch. 3. The transport device according to claim 2, further comprising a clutch that is turned on and off. 4. A front and rear wheel unit is pivotally supported on a frame so as to be rotatable on the axis of each axle or an extension of the axis and about the center in the width direction of the wheel unit. The transport device according to any one of claims 1 to 3, wherein the wheel unit is provided with a guide roller for guiding the movement of the wheel unit along the travel rail or the wheel tread. 5. The transport device according to claim 1, wherein another power source is arranged in the differential gear device, separately from the drive source.