JP2000072026A - Heavy object transport trolley - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To reduce the size and weight of a bogie frame, prolong tire life by suppressing tire wear, reduce manufacturing cost, and reduce running cost in a heavy load transporting vehicle. Provided is a heavy object transport trolley capable of achieving stable traveling. In order to support the front and rear end portions of a bogie frame 2 with a pair of left and right driven wheels 3 and 4, respectively, and to support a center portion of the bogie frame 2 in the front and rear direction with drive wheels 5 and 6, rigidity of the bogie frame 2 is achieved. Can be reduced, and the size and weight of the bogie frame 2 can be reduced.
Since the height of the carriage 1 can be lowered to lower the center of gravity, stable traveling can be realized. By reducing the weight of the carriage frame 1, the output of the rotary drive mechanism 9 can be reduced, so that production costs are reduced and fuel cost is reduced. Since it is possible to reduce the load burden shared by each wheel, tire wear of the driven wheels 3, 4 and the drive wheels 5, 6 can be suppressed as much as possible, and the running cost can be significantly reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a truck for transporting heavy objects, and more particularly, to a steerable driven wheel provided at both front and rear ends of a bogie frame, and a steerable drive wheel provided at a central portion in the front and rear direction of the bogie frame. The present invention relates to a heavy object transporting cart.

[0002]

2. Description of the Related Art Conventionally, in a steelworks yard, a container terminal, and the like, various heavy goods transport vehicles for transferring heavy goods such as coils, slabs, steel ingots, containers, and the like have been used. For example, a heavy object transporting truck has a truck frame for placing and supporting a heavy object, and a pair of left and right wheels respectively provided at front and rear ends of the truck frame. Transporting heavy objects by towing.

[0003] In recent years, there has been a tendency to automate and unmanned transport of heavy objects, and with such a tendency to promote automation and unmanned operation, heavy-load transport vehicles that travel automatically instead of the trailer pulling system described above have been put into practical use. Have been. For example, JP-A-8
Japanese Patent Application Publication No. 1999999/1999 discloses a vehicle provided with wheels provided near the front and rear ends on the lower surface side of the bogie, motors for rotating these front and rear wheels, sprockets provided on the front and rear wheels, and this motor. There is disclosed a self-propelled heavy object transporting trolley having an endless chain that is hung and that transmits the rotational driving force of a motor to wheels.

By the way, in this kind of heavy goods transport vehicle, the height of the vehicle is lowered to lower the center of gravity, thereby ensuring stable traveling, reducing the vehicle weight and reducing the manufacturing cost, and further reducing the wheel cost. It is desirable to minimize running of the tires by minimizing the wear of the tires and to extend the service life.

[0005]

In a conventional heavy object transporting trolley, the front and rear end portions of a long trolley frame for supporting a heavy object are supported via wheels. It is necessary to have a high rigidity, which results in a large bogie frame and a very heavy vehicle weight. Increasing the size of the bogie frame increases the vehicle height and increases the center of gravity, which is disadvantageous in terms of stable running. Since the vehicle weight becomes very heavy, a high-power drive source is required, the production cost is extremely high, and the fuel cost is also high. Further, tires of wheels supporting a large load are easily worn and have a short life, so that running costs are also increased. Therefore, it is conceivable to provide an intermediate shaft at the center of the vehicle body in the front-rear direction, and to provide a pair of left and right wheels that cannot be steered on the intermediate shaft. Slip occurs unless the steering angles of the front and rear steered wheels (the phases are opposite to each other) are made the same,
I cannot turn smoothly.

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the size and weight of a bogie frame in a heavy-duty transport truck for transporting heavy loads, to suppress tire wear to prolong its life, and to reduce manufacturing costs. That is, to keep running costs low, to achieve stable running, and to improve turning performance during turning.

[0007]

According to a first aspect of the present invention, there is provided a heavy object transporting trolley for transporting a heavy object, comprising a trolley frame for placing and supporting a heavy object, and a front and rear end portion of the trolley frame. At least one pair of right and left driven wheels provided, a driving wheel provided at a center portion in the front-rear direction of the bogie frame, first steering means for steering the plurality of driven wheels, and rotation for driving the driving wheels. And a second steering unit for steering the drive wheel.

Since the front and rear end portions of the bogie frame are supported by at least one pair of right and left driven wheels, and the center portion of the bogie frame in the front and rear direction is supported by drive wheels, the rigidity of the bogie frame can be reduced. The size and weight of the frame can be reduced. The downsizing of the bogie frame makes it possible to lower the center of gravity by lowering the height of the heavy goods transport bogie, thereby achieving stable running. The weight reduction of the bogie frame allows the load shared by each wheel Since the burden can be reduced, the wear of the tires of the driven wheels and the drive wheels can be suppressed as much as possible.

When the heavy load transport vehicle is traveling straight, the driving wheels are rotated by driving the rotary drive means, and the driven wheels are also rotated so as to follow, so that the heavy load transport vehicle can move forward or backward. At the time of turning of the heavy object transporting vehicle, the driving wheels are steered by the second steering means while the driven wheels are steered by the first steering means according to the turning radius, and the driving wheels are rotated by the driving of the rotary driving means. The heavy object transport cart can be turned.

A heavy object transporting vehicle according to a second aspect is characterized in that, in the invention of the first aspect, a pair of left and right driving wheels that are independently driven are provided as the driving wheels. When turning a heavy object transporting trolley, left and right 1 according to the turning radius
By independently rotating the pair of drive wheels, the wear of the tire due to the rotation difference between the inner and outer wheels of the pair of drive wheels can be minimized.

According to a third aspect of the present invention, there is provided a heavy object transporting vehicle according to the first aspect of the present invention, wherein a pair of left and right driving wheels connected via a differential gear and driven by common rotary driving means are provided as the driving wheels. It is characterized by the following. By rotating the pair of left and right drive wheels via the differential gear when the heavy load transport vehicle turns, it is possible to minimize wear of the tire due to the rotation difference between the inner and outer wheels of the pair of drive wheels.

According to a fourth aspect of the present invention, there is provided a heavy object transporting vehicle.
In the invention according to any one of the first to third aspects, the first steering means includes:
A plurality of driven wheels are configured to be independently steerable, and the second steering means is configured to be able to steer the drive wheels independently of the driven wheels. The axle of each driven wheel and the axle of the drive wheel can be steered so as to be directed to the turning center of the heavy load transport vehicle, and the heavy load transport vehicle can be smoothly turned.

According to a fifth aspect of the present invention, there is provided a heavy object transporting vehicle.
3. In the invention according to any one of the third to third aspects, the heavy object transporting truck has a guide sensor for detecting a guiding section formed along a traveling path, and the guide sensor detects the guiding section along the guiding section while detecting the guiding section. And is configured to be capable of automatic traveling. The heavy object transport vehicle can automatically travel along the guide portion while detecting the guide portion with the guide sensor.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. The present embodiment is an example of a case where the present invention is applied to an unmanned container transport vehicle (corresponding to a heavy object transport vehicle) that transports containers in a container terminal.

As shown in FIGS. 1 and 2, an unmanned container carrier 1 (hereinafter referred to as a carrier) is provided on a carrier frame 2 for mounting and supporting a container C and a front end portion of the carrier frame 2. A pair of left and right driven wheels 3 and 4 and a pair of left and right driven wheels 3 and 4 provided at the rear end of the bogie frame 2.
And a pair of left and right drive wheels 5 and 6 provided at the center in the front-rear direction of the bogie frame 2.

The driven wheels 3 and 4 have the following driven wheels 3 and 4
4 are provided with four first steering mechanisms 7 for independently steering the drive wheels 4, respectively. A second steering mechanism for steering the drive wheels 5, 6 independently of the driven wheels 3, 4 is provided on the drive wheels 5, 6. 8 and a rotary drive mechanism 9 for rotating the pair of drive wheels 5 and 6. The transport trolley 1 includes a travel control device (not shown) that controls the first steering mechanism 7, the second steering mechanism 8, and the rotation drive mechanism 9 to control the travel of the transport trolley 1.

The bogie frame 2 is, for example, formed in a substantially rectangular shape having a length of about 10 m, a width of about 2 m, and a vehicle height of about 1.5 m.
Are installed respectively. A mounting surface 2b for mounting and supporting the container C is formed on the upper surface of the bogie frame 2, and a plurality of guide members (not shown) are erected on the mounting surface 2b. Place the container C on the loading surface 2b from above using a crane or the like.
When the container C is placed on the placement surface 2b, the guide member positions the container C on the placement surface 2b.

As shown in FIGS. 3 and 4, the front driven wheels 3, 4 and the rear driven wheels 3, 4 have a symmetric structure in which a pair of left and right driven wheels 3, 4 is symmetrical. That is, each of the driven wheels 3 and 4 is configured as a double tire wheel including an inner wheel 10 and an outer wheel 11, and the inner wheel 10 and the outer wheel 11 are independently rotatably supported by a horizontal support shaft 13 fixed to a bracket 12. Bracket 1
2 is fixed to a rotating plate 14, and the rotating plate 14 is supported by the bogie frame 2 via a bearing 15 so as to be rotatable around a vertical axis.

Each of the first steering mechanisms 7 includes a hydraulic cylinder 19
The hydraulic cylinder 19 has a cylinder body 1
9a is fixed to the trolley frame 2, and the piston rod 19
The leading end of b is rotatably connected to the rotating plate 14.
For the hydraulic cylinder 19, the diesel engine 16
The hydraulic pressure is supplied and discharged from a hydraulic supply source including the oil pump 17 and the valve unit 18 and the like. This hydraulic cylinder 19
The piston rod 19b expands and contracts by the
4 rotates around the vertical axis, and the driven wheels 3 and 4 are steered. For example, when turning a curve having one radius of curvature, the transport vehicle 1 drives and controls each of the first steering mechanisms 7 and steers the front and rear driven wheels 3 and 4 so that they have opposite phases.
The vehicle turns so that the axles of all the driven wheels 3 and 4 face the turning center.

As shown in FIGS. 5 and 6, a pair of left and right driving wheels 5 and 6 are disposed near the center between the front and rear driven wheels 3 and 4 and are connected to the left and right ends of the differential gear 20. I have. An axle case 20a extending from the differential case of the differential gear 20 is a pair of left and right brackets 2.
1, and these brackets 21 are supported by the bogie frame 2 via a suspension 22 and a block member 23. The suspension 22 includes a leaf spring laminate 24 disposed at the upper end of each bracket 21, and a pair of support members 25 that support the front and rear ends of each leaf spring laminate 24 and connect to the block member 23.

In the suspension 22, the load distribution of the driven wheels 3, 4 and the driving wheels 5, 6 depends on various conditions such as the strength and size of the load, the driven wheels 3, 4, and the driving wheels 5, 6. So that the above-mentioned leaf spring laminate 24
Is set. The rotation drive mechanism 9 has a hydraulic motor 29 and a differential gear 20, and hydraulic pressure is supplied to and discharged from the hydraulic motor 29 from the hydraulic pressure supply source. The pair of left and right drive wheels 5 and 6 are driven to rotate without slip.

As shown in FIG. 1, FIG. 2, and FIG. 7, the second steering mechanism 8 is configured to be able to independently steer the driving wheels 5 and 6, and the second steering mechanism 8 is mainly connected to the driving wheels 5 and 6. The hub unit 30 and the steering knuckle 31 at least on the fixed support side of the hub unit 30 are steered to
0a. The hydraulic pressure is supplied to and discharged from the hydraulic cylinder 32 from the hydraulic pressure supply source.

The hub unit 30 has a substantially flange-shaped axle hub 33 for connecting wheels (not shown) of the drive wheels 5 and 6 via a plurality of bolts, and a bearing 33 a and a seal member on the outer periphery of the axle hub 33. A steering knuckle 31 externally provided through a shaft 33b and an outboard joint shaft 34 (hereinafter, referred to as a joint shaft) which is provided in an axle hub 33, is spline-connected, and is fixed by a lock nut 33c, are provided inside the axle case 20a. The drive shaft 36 is spline-connected to the joint shaft 34 via a joint mechanism 35.

The joint mechanism 35 has a function of transmitting a driving force from the drive shaft 36 to the joint shaft 34 by absorbing a deviation of the axis between the drive shaft 36 and the joint shaft 34. Therefore, the steering knuckle 31 swings around the vertical axis by the expansion and contraction drive of the hydraulic cylinder 32, and the axle hub 33 swings, so that the drive wheels 5, 6 are steered. The load received by the drive wheels 5 and 6 is transmitted from the wheels to the axle hub 33, transmitted from the axle hub 33 to the steering knuckle 31 via the bearing 33a, and from the steering knuckle 31 to the bracket 21 via a connection arm (not shown). And transmitted to the suspension 22.

As shown in FIGS. 1 and 2, the bogie frame 2
, A diesel engine 16, a flywheel 37, a fuel tank 38, a radiator 39, an oil cooler 40, a muffler 41, a speed reducer 42, an oil pump 17,
Batteries 43 and 44 are provided, and a navigation antenna 45 is provided. An oil tank 46, a valve unit 18, a navigation antenna 47, a control unit 48, and the like are provided at a rear portion of the bogie frame 2. The traveling control device includes navigation antennas 45 and 47, a control unit 48, and the like. For example, the carrier 1 controls the control unit 48 when the navigation antennas 45 and 47 receive a signal for driving the diesel engine 16. It has a function to automatically travel in the container terminal based on the map information possessed by.

When the diesel engine 16 is operated by the light oil supplied from the fuel tank 38, the oil pump 17 is driven via the speed reducer 42, and the pressurized hydraulic oil is supplied to the first steering mechanism via the valve unit 18. 7, a hydraulic motor 19 of the rotary drive mechanism 9,
It is supplied to the hydraulic cylinder 32 of the second steering mechanism 8. During operation of the diesel engine 16, the flywheel 37 smoothes the rotational output of the diesel engine 16, the radiator 39 cools the diesel engine 16, and the muffler 41 reduces the noise of exhaust gas. The battery 43 serves as a power supply for electrical control, and the battery 44 serves as another power supply for power supply.

FIG. 8 shows an example of the case where the carriage 1 is turned to the front left at a turning radius R, and the driven wheels are steered by the traveling control device so that the driven wheels 3, 3 are in the opposite phase and have the steering angle α. The driven wheels 4, 4 are steered so as to have the steering angle β in opposite phases, and the drive wheels 5, 6 are steered so as to have a steering angle smaller than the steering angle α and the steering angle β. The axles of the driving wheels 3, 4 and the axles of the driving wheels 5, 6 are always directed to the turning center X.

Thus, the driven wheels 3, 4 and the drive wheels 5, 6
Are always directed to the turning center X, the carrier 1 smoothly turns with the turning radius R. The distance between the driven wheel 3 and a straight line Y that passes through the turning center X and is parallel to the length direction of the carriage 1 is R1, and the distance between the straight line Y and the driven wheel 4 is R2.
When the distance between the driven wheel 3 and the driving wheel 5 is L, the relational expressions of tan α = L / R1 and tan β = L / R2 hold.

Next, the operation of the carrier 1 will be described. When the transport vehicle 1 moves straight, the drive wheels 5 and 6 are rotated at the same rotational speed by the drive of the hydraulic motor 29 of the rotary drive mechanism 9, and the driven wheels 3 and 4 are also rotated to follow the transport vehicle 1 to move forward or forward. You can move backward.

When the transport vehicle 1 is turning, the driven wheels 3, 4 are sequentially steered by the second steering mechanism 8 while the driven wheels 3, 4 are sequentially steered by the first steering mechanism 7 according to the turning radius. By rotating the drive wheels 5, 6 by driving the hydraulic motor 29 of the rotary drive mechanism 9, all the axles of the driven wheels 3, 4 and the drive wheels 5, 6 are always directed to the turning center. The turning radius can be turned smoothly. By rotating the pair of left and right driving wheels 5 and 6 via the differential gear 20 during this turning, it is possible to minimize the wear of the tire due to the rotation difference between the inner and outer wheels of the pair of driving wheels 5 and 6. .

Since the pair of left and right drive wheels 5 and 6 are configured to be steerable, it is not always necessary to set the steering state as shown in FIG. 8, but the steering angles of the front driven wheels 3 and 4 and the rear side The steering angles of the driven wheels 3 and 4 can be set independently, and the vehicle can turn while drawing a trajectory different from a simple arc trajectory, thereby significantly improving the turning traveling performance. According to the carrier 1, the front and rear ends of the carrier frame 2 are supported by a pair of left and right driven wheels 3 and 4, and the center of the carrier frame 2 in the front and rear direction is supported by drive wheels 5 and 6. The rigidity of the frame 2 can be reduced, and the size and weight of the bogie frame 2 can be reduced.

By reducing the size of the bogie frame 2, the height of the transport bogie 1 can be reduced and the center of gravity can be reduced, so that stable traveling can be realized. By reducing the weight of the bogie frame 2, for example, the output of the hydraulic motor 29 of the rotary drive mechanism 9 can be reduced, so that the manufacturing cost can be reduced and the fuel cost can be reduced. Further, since the load burden shared by each of the driven wheels 3, 4 and the driving wheels 5, 6 can be reduced, the wear of the tires of the driven wheels 3, 4 and the driving wheels 5, 6 can be suppressed as much as possible to extend the life. . Thus, the running cost can be kept low.

Next, a modified embodiment in which the carrier 1 is partially modified will be described. However, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 9, the transport trolley 1B is provided with a rotary drive mechanism 9A that drives the pair of drive wheels 5, 6 to rotate independently. 1
The pair of drive wheels 5 and 6 are directly connected to the output shafts (not shown) of the pair of hydraulic motors 29A of the rotary drive mechanism 9A, respectively. It is configured to be. According to the carrier 1B,
The same operation and effect as those of the above embodiment can be obtained.

As shown in FIG. 10, the transport vehicle 1C has one drive wheel 53 at the center in the vehicle width direction at the center in the front-rear direction of the vehicle frame 2, and
Is provided with a rotation drive mechanism 9B for driving the rotation.
The drive wheel 53 is directly connected to an output shaft (not shown) of the hydraulic motor 29B of the rotary drive mechanism 9B, and a steering mechanism 8A for steering the drive wheel 53 is provided. When a pair of drive wheels is provided, it is necessary to independently drive the pair of drive wheels or provide a differential gear in order to suppress tire wear due to a rotation difference between the inner and outer wheels, but it is necessary to provide a central portion in the vehicle width direction. By providing one drive wheel 53, the configuration of the rotary drive mechanism 9B is simplified, and the drive wheel 53 by turning of the transport vehicle 1C is provided.
Of the tire can be suppressed. Other operations and effects similar to those of the above-described embodiment are exhibited.

Next, a modified embodiment in which the carrier 1 is partially modified will be described. As shown in FIG. 11, for example, a guide tape 50 (corresponding to a guide portion) provided with magnetism is attached to the traveling path L of the transport vehicle 1 </ b> A in the container terminal along substantially the center of the width of the traveling path L. It is attached. A pair of guide sensors 51 for detecting the guide tape 50 is provided on the lower surface side of the trolley frame 2 in the front-rear direction. Autonomous driving along the road. Each of the pair of guide sensors 51 has, for example, 16 Hall elements arranged in a row in the width direction of the guide tape 50. Of the pair of front and rear guide sensors 51, the front guide sensor 51 is disposed near the front end of the bogie frame 2, and the rear guide sensor 51 is connected to the rear driven wheels 3 and 4 on the bogie frame 2. It is located near the axle. The transport trolley 1A has substantially the same configuration as the transport trolley 1 described above, except for the guide sensor 51.

Next, a description will be given of a guiding technique for guiding the carriage 1A along the guide tape 50. FIG.
As shown in FIG. 12, each of the pair of guide sensors 51 has one
When six hole elements 52 are provided and only the five hole elements 52 indicated by black circles detect the guide tape 50 and are turned ON, the carrier 1A based on the detection signals of the sixteen hole elements 52 The first steering mechanism 7, the second steering mechanism 8, and the rotation drive mechanism 9 are controlled by the control device such that the center line 1a of the vehicle body, that is, the center line of the pair of guide sensors 51 coincides with the center line 50a of the guide tape 50. I do.

For example, as shown in FIG. 13, when the guide tape 50 has a curved portion having a constant radius R and straight portions continuous at both ends of the curved portion, the carriage 1A is moved from the straight portion on one end to the curved portion. When the left turn guidance or the right turn guidance is performed, a drive signal is output to the hydraulic motor 29 based on the detection signals from the pair of guide sensors 51, and the rotation speed of the hydraulic motor 29 is controlled. 29 through the differential gear 20 to drive wheels 5, 6
And the steering angles of the driven wheels 3 and 4 and the drive wheels 5 and 6 are synchronized with the rotation speed of the hydraulic motor 29, and the axles of the driven wheels 3 and 4 and the axles of the drive wheels 5 and 6, respectively. Is determined so as to face the turning center of the carrier 1A.
Guides a left turn guide or a right turn guide from the straight portion on one end side to the curved portion.

As shown in FIG. 14, when the transport vehicle 1A is guided to turn left or right on a curved portion, the rotational driving force of the hydraulic motor 29 is driven via the differential gear 20 in the same manner as described above. The driving wheels 5 and 6 are independently transmitted to the wheels 5 and 6, respectively, and the driven wheels 3 and 4 are controlled in synchronization with the rotation speed of the hydraulic motor 29, and the driven angles of the driven wheels 5 and 6 are set to 0 degrees. The axles 3 and 4 and the axles of the drive wheels 5 and 6 are determined so as to face the turning center of the carrier 1A.
A guides left turn guidance or right turn guidance on the curved part.

As shown in FIG. 15, when the transport vehicle 1A is guided to turn left or right from the curved portion to the straight portion on the other end side, the rotational driving force of the hydraulic motor 29 is differentially changed in the same manner as described above. Independently transmitted to the driving wheels 5 and 6 via the gear 20, the steering angles of the driven wheels 3 and 4 and the driving wheels 5 and 6 are synchronized with the rotation speed of the hydraulic motor 29, respectively. Axle and drive axles 1 and 2
Is determined so as to face the turning center, and the transport vehicle 1A guides the left turn or the right turn from the curved portion to the straight portion on the other end side.

As described above, the axle of each of the driven wheels 3 and 4 and the axles of the drive wheels 5 and 6 in the vicinity of the entrance to the curved portion and the vicinity of the exit from the curved portion when the vehicle is turned, in particular, are set. By determining the steering angles of the driven wheels 3 and 4 and the steering angles of the drive wheels 5 and 6 so that all of them face the turning center of the transport vehicle 1A, the turning is smoothly guided. According to the transport trolley 1A, the same operation and effect as those of the above embodiment can be obtained.

Next, a description will be given of a modified example in which the carrier is partially changed. 1) Each driven wheel may be constituted by a single tire wheel. Since the drive wheels are provided at the center of the bogie frame 2 in the front-rear direction, the rigidity of the bogie frame 2 can be reduced, and the size and weight of the bogie frame 2 can be reduced. The operation and effect of are obtained. 2) Three or more driven wheels may be provided at both front and rear ends of the bogie frame 2 respectively. 3) Three or more drive wheels may be provided at the center of the bogie frame 2 in the front-rear direction, and these drive wheels may be configured to be driven independently, or may be connected via a differential gear.

4) The first steering mechanism 7 for steering each driven wheel and the second steering mechanism 8 for steering the drive wheels are provided with various types such as a rack and pinion type in addition to the hydraulic cylinder type as in the above-described embodiment. Are applicable. 5) Instead of the hydraulic motor driving the drive wheels, an electric motor, an engine, or the like can be applied. 6] The transport carts 1, 1A, 1B, and 1C transport the container C, but change the structure and the like of the truck frame 2 to transport, for example, heavy objects such as coils and slabs in a steelworks yard. The present invention can be applied as a truck or other various heavy load transporting trucks.

[0043]

According to the present invention, the front and rear ends of the bogie frame are supported by at least one pair of right and left driven wheels, and the front and rear central portions of the bogie frame are supported by drive wheels. Therefore, the rigidity of the bogie frame can be reduced, and the size and weight of the bogie frame can be reduced. The downsizing of the bogie frame makes it possible to lower the center of gravity of the heavy-duty carrier by lowering the height of the truck, thereby realizing stable running. As a result, the production cost and the fuel cost can be reduced, and the load shared by each wheel can be reduced, so that the wear of the driven wheels and the drive wheels can be minimized. As a result, the running cost of the heavy load transporting vehicle can be significantly reduced.

When the heavy object transport vehicle is turning, the drive wheels are steered by the second steering means while the driven wheels are steered by the first steering means according to the turning radius, and the drive wheels are rotated by the drive of the rotary drive means. As a result, the heavy load transport vehicle can be turned. In particular, since the pair of left and right drive wheels provided at the center portion in the front-rear direction of the bogie frame can be steered by the second steering means, it is not necessary to steer the steering angles of the front and rear driven wheels at the same time during the turning travel. Increased freedom of travel,
Turning performance is improved.

According to the second aspect of the present invention, a pair of left and right driven wheels that are independently driven are provided as the driving wheels. By independently driving the pair of drive wheels, it is possible to minimize the wear of the tire due to the rotation difference between the inner and outer wheels of the pair of drive wheels. The other effects are the same as those of the first aspect.

According to the third aspect of the present invention, a pair of left and right driving wheels connected via a differential gear and driven by a common rotary driving means are provided as driving wheels. By rotating the pair of left and right drive wheels via the differential gear when the bogie turns, it is possible to minimize wear of the tire due to the rotation difference between the inner and outer wheels of the pair of drive wheels. The other effects are the same as those of the first aspect.

According to the heavy object transporting cart of the fourth aspect, the first
The steering means is configured to be able to independently steer the plurality of driven wheels, and the second steering means is configured to be able to steer the drive wheels independently of the driven wheels. By steering the axles so as to be directed to the turning center of the heavy load transport vehicle, the heavy load transport vehicle can be turned smoothly. In addition, the same effect as any one of the first to third aspects is obtained.

According to a fifth aspect of the present invention, there is provided a heavy object transporting trolley, wherein the heavy object transporting trolley has a guide sensor for detecting a guiding part formed along the traveling path, and the guiding part detects the guiding part with the guide sensor. Because it was configured to be able to automatically travel along
The heavy object transport vehicle can automatically travel along the guide portion while detecting the guide portion with the guide sensor. In addition, the same effect as any one of the first to third aspects is obtained.

[Brief description of the drawings]

FIG. 1 is a perspective plan view of a heavy object transporting truck according to an embodiment of the present invention.

FIG. 2 is a left side view of the heavy object transporting cart of FIG. 1;

FIG. 3 is a horizontal cross-sectional view of a main part in FIG. 1 of the heavy object transporting cart.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is an enlarged sectional view taken along line VV of FIG. 1;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 7 is a sectional view taken along line VII-VII of FIG. 6;

FIG. 8 is an explanatory view showing a turning state of the heavy object transporting cart.

FIG. 9 is a perspective plan view of a heavy object transporting truck according to another embodiment.

FIG. 10 is a perspective plan view of a heavy object transporting truck according to another embodiment.

FIG. 11 is a schematic plan view of a heavy object transporting truck according to another embodiment.

FIG. 12 is an explanatory diagram showing a positional relationship between a guide sensor and a guide unit of a heavy goods transporting truck according to another embodiment.

FIG. 13 is a diagram illustrating a first state in which the heavy object transporting trolley automatically turns.
It is explanatory drawing of a stage.

FIG. 14 illustrates a second state in which the heavy object transporting trolley performs automatic turning traveling.
It is explanatory drawing of a stage.

FIG. 15 shows a third state in which the heavy object transporting trolley performs automatic turning traveling.
It is explanatory drawing of a stage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveyor truck 2 Truck frame 3, 4 Driven wheel 5, 6 Drive wheel 7 1st steering mechanism 8 2nd steering mechanism 9 Rotation drive mechanism 20 Differential gear

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[Procedure amendment]

[Submission date] August 26, 1999 (1999.8.2
6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] Heavy object transport trolley

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a truck for transporting heavy objects, and more particularly, to a steerable driven wheel provided at both front and rear ends of a bogie frame, and a steerable drive wheel provided at a central portion in the front and rear direction of the bogie frame. The present invention relates to a heavy object transporting trolley.

[0002]

2. Description of the Related Art Conventionally, in a steelworks yard, a container terminal, and the like, various heavy goods transport vehicles for transferring heavy goods such as coils, slabs, steel ingots, containers, and the like have been used. For example, a heavy object transporting truck has a truck frame for placing and supporting a heavy object, and a pair of left and right wheels respectively provided at front and rear ends of the truck frame. Transporting heavy objects by towing.

[0003] In recent years, there has been a tendency to automate and unmanned transport of heavy objects, and with such a tendency to promote automation and unmanned operation, heavy-load transport vehicles that travel automatically instead of the trailer pulling system described above have been put into practical use. Have been. For example, JP-A-8
Japanese Patent Application Publication No. 1999999/1999 discloses a vehicle provided with wheels provided near the front and rear ends on the lower surface side of the bogie, motors for rotating these front and rear wheels, sprockets provided on the front and rear wheels, and this motor. There is disclosed a self-propelled heavy object transporting trolley having an endless chain that is hung and that transmits the rotational driving force of a motor to wheels.

By the way, in this kind of heavy goods transport vehicle, the height of the vehicle is lowered to lower the center of gravity, thereby ensuring stable traveling, reducing the vehicle weight and reducing the manufacturing cost, and further reducing the wheel cost. It is desirable to minimize running of the tires by minimizing the wear of the tires and to extend the service life.

[0005]

In a conventional heavy object transporting trolley, the front and rear end portions of a long trolley frame for supporting a heavy object are supported via wheels. It is necessary to have a high rigidity, which results in a large bogie frame and a very heavy vehicle weight. Increasing the size of the bogie frame increases the vehicle height and increases the center of gravity, which is disadvantageous in terms of stable running. Since the vehicle weight becomes very heavy, a high-power drive source is required, the production cost is extremely high, and the fuel cost is also high. Further, tires of wheels supporting a large load are easily worn and have a short life, so that running costs are also increased. Therefore, it is conceivable to provide an intermediate shaft at the center in the front-rear direction of the vehicle body and provide a pair of left and right wheels that cannot be steered on the intermediate shaft. In this case, the turning center during turning is one point on the extension of the intermediate shaft. Slip occurs unless the steering angles of the front and rear steered wheels (the phases are opposite to each other) are made the same,
I cannot turn smoothly.

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the size and weight of a bogie frame in a heavy-duty transport truck for transporting heavy loads, to suppress tire wear to prolong its life, and to reduce manufacturing costs. That is, to keep running costs low, to achieve stable running, and to improve turning performance during turning.

[0007]

According to a first aspect of the present invention, there is provided a heavy object transporting trolley for transporting a heavy object, comprising a trolley frame for placing and supporting a heavy object, and a front and rear end portion of the trolley frame. A pair of left and right driven wheels provided, a pair of left and right driven wheels provided at a central portion in the front-rear direction of the bogie frame and independently driven, and first steering means for steering the plurality of driven wheels; Left and right drive wheels
It is characterized by comprising a rotation drive means for independently rotating and driving, and a second steering means for steering the drive wheel.

Since the front and rear end portions of the bogie frame are supported by at least one pair of right and left driven wheels, and the center portion of the bogie frame in the front and rear direction is supported by drive wheels, the rigidity of the bogie frame can be reduced. The size and weight of the frame can be reduced. The downsizing of the bogie frame makes it possible to lower the center of gravity by lowering the height of the heavy goods transport bogie, thereby achieving stable running. The weight reduction of the bogie frame allows the load shared by each wheel Since the burden can be reduced, the wear of the tires of the driven wheels and the drive wheels can be suppressed as much as possible.

When the heavy load transport vehicle is traveling straight, the driving wheels are rotated by driving the rotary drive means, and the driven wheels are also rotated so as to follow, so that the heavy load transport vehicle can move forward or backward. At the time of turning of the heavy object transporting vehicle, the driving wheels are steered by the second steering means while the driven wheels are steered by the first steering means according to the turning radius, and the driving wheels are rotated by the driving of the rotary driving means. The heavy object transport cart can be turned.

[0010] Then, as the drive wheels, the drive wheels of the right and left pair which is independently driven are provided, during turning of heavy transport vehicle, the driving wheels of the left and right pair each independently in accordance with the turning radius By performing the rotational drive, it is possible to minimize the wear of the tire due to the rotational difference between the inner and outer wheels of the pair of drive wheels.

According to a second aspect of the present invention, there is provided a heavy object transporting cart .
It has a configuration similar to that of the invention, but with a differential
A common turn that drives a pair of left and right drive wheels through gears
Since the rolling drive means is provided , the left and right driving wheels are driven to rotate via differential gears when the heavy load transport vehicle turns, thereby reducing tire wear due to the rotation difference between the inner and outer wheels of the pair of driving wheels. It can be suppressed as much as possible. Other billing
It has the same effect as item 1.

According to a third aspect of the present invention, there is provided a heavy object transporting vehicle.
In the second aspect , the first steering means is configured to be capable of independently steering a plurality of driven wheels, and the second steering means is configured to be capable of steering a drive wheel independently of the driven wheels. It is a feature. The axle of each driven wheel and the axle of the drive wheel can be steered so as to be directed to the turning center of the heavy load transport vehicle, and the heavy load transport vehicle can be smoothly turned.

According to a fourth aspect of the present invention, there is provided the heavy object transporting vehicle according to the third aspect of the present invention, wherein the heavy object transporting vehicle has a guide sensor for detecting a guiding portion formed along the traveling path. It is characterized in that it is configured to be able to automatically travel along the guidance unit while detecting the guidance unit.
The heavy object transport vehicle can automatically travel along the guide portion while detecting the guide portion with the guide sensor. Claim 5
Of the present invention is substantially the same as that of the first aspect.
, But in the vehicle width direction at the center in the front-rear direction of the bogie frame
One drive wheel is provided in the center and this drive wheel is driven to rotate
One rotation driving means is provided. Therefore, drive
The structure of the rotary drive means for rotating the wheels is simplified, and turning
It is possible to suppress the wear of the driving wheel tires due to running.
You. Other operations are the same as those of the first aspect.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. The present embodiment is an example in which the present invention is applied to an unmanned container carrier (which corresponds to a heavy object carrier) that transports containers in a container terminal.

As shown in FIGS. 1 and 2, an unmanned container carrier 1 (hereinafter referred to as a carrier) is provided on a carrier frame 2 for mounting and supporting a container C and a front end portion of the carrier frame 2. A pair of left and right driven wheels 3 and 4 and a pair of left and right driven wheels 3 and 4 provided at the rear end of the bogie frame 2.
And a pair of left and right drive wheels 5 and 6 provided at the center in the front-rear direction of the bogie frame 2.

The driven wheels 3 and 4 have the following driven wheels 3 and 4
4 are provided with four first steering mechanisms 7 for independently steering the drive wheels 4, respectively. A second steering mechanism for steering the drive wheels 5, 6 independently of the driven wheels 3, 4 is provided on the drive wheels 5, 6. 8 and a rotary drive mechanism 9 for rotating the pair of drive wheels 5 and 6. The transport trolley 1 includes a travel control device (not shown) that controls the first steering mechanism 7, the second steering mechanism 8, and the rotation drive mechanism 9 to control the travel of the transport trolley 1.

The bogie frame 2 is, for example, formed in a substantially rectangular shape having a length of about 10 m, a width of about 2 m, and a vehicle height of about 1.5 m.
Are installed respectively. A mounting surface 2b for mounting and supporting the container C is formed on the upper surface of the bogie frame 2, and a plurality of guide members (not shown) are erected on the mounting surface 2b. Place the container C on the loading surface 2b from above using a crane or the like.
When the container C is placed on the placement surface 2b, the guide member positions the container C on the placement surface 2b.

As shown in FIGS. 3 and 4, the front driven wheels 3, 4 and the rear driven wheels 3, 4 have a symmetric structure in which a pair of left and right driven wheels 3, 4 is symmetrical. That is, each of the driven wheels 3 and 4 is configured as a double tire wheel including an inner wheel 10 and an outer wheel 11, and the inner wheel 10 and the outer wheel 11 are independently rotatably supported by a horizontal support shaft 13 fixed to a bracket 12. Bracket 1
2 is fixed to a rotating plate 14, and the rotating plate 14 is supported by the bogie frame 2 via a bearing 15 so as to be rotatable around a vertical axis.

Each of the first steering mechanisms 7 includes a hydraulic cylinder 19
The hydraulic cylinder 19 has a cylinder body 1
9a is fixed to the trolley frame 2, and the piston rod 19
The leading end of b is rotatably connected to the rotating plate 14.
For the hydraulic cylinder 19, the diesel engine 16
The hydraulic pressure is supplied and discharged from a hydraulic supply source including the oil pump 17 and the valve unit 18 and the like. This hydraulic cylinder 19
The piston rod 19b expands and contracts by the
4 rotates around the vertical axis, and the driven wheels 3 and 4 are steered. For example, when turning a curve having one radius of curvature, the transport vehicle 1 drives and controls each of the first steering mechanisms 7 and steers the front and rear driven wheels 3 and 4 so that they have opposite phases.
The vehicle turns so that the axles of all the driven wheels 3 and 4 face the turning center.

As shown in FIGS. 5 and 6, a pair of left and right driving wheels 5 and 6 are disposed near the center between the front and rear driven wheels 3 and 4 and are connected to the left and right ends of the differential gear 20. I have. An axle case 20a extending from the differential case of the differential gear 20 is a pair of left and right brackets 2.
1, and these brackets 21 are supported by the bogie frame 2 via a suspension 22 and a block member 23. The suspension 22 includes a leaf spring laminate 24 disposed at the upper end of each bracket 21, and a pair of support members 25 that support the front and rear ends of each leaf spring laminate 24 and connect to the block member 23.

In the suspension 22, the load distribution of the driven wheels 3, 4 and the driving wheels 5, 6 depends on various conditions such as the strength and size of the load, the driven wheels 3, 4, and the driving wheels 5, 6. So that the above-mentioned leaf spring laminate 24
Is set. The rotation drive mechanism 9 has a hydraulic motor 29 and a differential gear 20, and hydraulic pressure is supplied to and discharged from the hydraulic motor 29 from the hydraulic pressure supply source. The pair of left and right drive wheels 5 and 6 are driven to rotate without slip.

[0022] 1, 2, as shown in FIG. 7, the second steering mechanism 8 is configured to steering rudder available-driving wheels 5 and 6 each independently, primarily, the drive wheels 5,6 is connected Hub unit 30
And steering the steering knuckle 31, which is at least the fixed support side of the hub unit 30, to drive the axle case 20a.
And a hydraulic cylinder 32 connected to the The hydraulic pressure is supplied to and discharged from the hydraulic cylinder 32 from the hydraulic pressure supply source.

The hub unit 30 has a substantially flange-shaped axle hub 33 for connecting wheels (not shown) of the drive wheels 5 and 6 via a plurality of bolts, and a bearing 33 a and a seal member on the outer periphery of the axle hub 33. A steering knuckle 31 externally provided through a shaft 33b and an outboard joint shaft 34 (hereinafter, referred to as a joint shaft) which is provided in an axle hub 33, is spline-connected, and is fixed by a lock nut 33c, are provided inside the axle case 20a. The drive shaft 36 is spline-connected to the joint shaft 34 via a joint mechanism 35.

The joint mechanism 35 has a function of transmitting a driving force from the drive shaft 36 to the joint shaft 34 by absorbing a deviation of the axis between the drive shaft 36 and the joint shaft 34. Therefore, the steering knuckle 31 swings around the vertical axis by the expansion and contraction drive of the hydraulic cylinder 32, and the axle hub 33 swings, so that the drive wheels 5, 6 are steered. The load received by the drive wheels 5 and 6 is transmitted from the wheels to the axle hub 33, transmitted from the axle hub 33 to the steering knuckle 31 via the bearing 33a, and from the steering knuckle 31 to the bracket 21 via a connection arm (not shown). And transmitted to the suspension 22.

As shown in FIGS. 1 and 2, the bogie frame 2
, A diesel engine 16, a flywheel 37, a fuel tank 38, a radiator 39, an oil cooler 40, a muffler 41, a speed reducer 42, an oil pump 17,
Batteries 43 and 44 are provided, and a navigation antenna 45 is provided. An oil tank 46, a valve unit 18, a navigation antenna 47, a control unit 48, and the like are provided at a rear portion of the bogie frame 2. The traveling control device includes navigation antennas 45 and 47, a control unit 48, and the like. For example, the carrier 1 controls the control unit 48 when the navigation antennas 45 and 47 receive a signal for driving the diesel engine 16. It has a function to automatically travel in the container terminal based on the map information possessed by.

When the diesel engine 16 is operated by the light oil supplied from the fuel tank 38, the oil pump 17 is driven via the speed reducer 42, and the pressurized hydraulic oil is supplied to the first steering mechanism via the valve unit 18. 7, a hydraulic motor 19 of the rotary drive mechanism 9,
It is supplied to the hydraulic cylinder 32 of the second steering mechanism 8. During operation of the diesel engine 16, the flywheel 37 smoothes the rotational output of the diesel engine 16, the radiator 39 cools the diesel engine 16, and the muffler 41 reduces the noise of exhaust gas. The battery 43 serves as a power supply for electrical control, and the battery 44 serves as another power supply for power supply.

FIG. 8 shows an example of the case where the carriage 1 is turned to the front left at a turning radius R, and the driven wheels are steered by the traveling control device so that the driven wheels 3, 3 are in the opposite phase and have the steering angle α. The driven wheels 4, 4 are steered so as to have the steering angle β in opposite phases, and the drive wheels 5, 6 are steered so as to have a steering angle smaller than the steering angle α and the steering angle β. The axles of the driving wheels 3, 4 and the axles of the driving wheels 5, 6 are always directed to the turning center X.

Thus, the driven wheels 3, 4 and the drive wheels 5, 6
Are always directed to the turning center X, the carrier 1 smoothly turns with the turning radius R. The distance between the driven wheel 3 and a straight line Y that passes through the turning center X and is parallel to the length direction of the carriage 1 is R1, and the distance between the straight line Y and the driven wheel 4 is R2.
When the distance between the driven wheel 3 and the driving wheel 5 is L, the relational expressions of tan α = L / R1 and tan β = L / R2 hold.

Next, the operation of the carrier 1 will be described. When the transport vehicle 1 moves straight, the drive wheels 5 and 6 are rotated at the same rotational speed by the drive of the hydraulic motor 29 of the rotary drive mechanism 9, and the driven wheels 3 and 4 are also rotated to follow the transport vehicle 1 to move forward or forward. You can move backward.

When the transport vehicle 1 is turning, the driven wheels 3, 4 are sequentially steered by the second steering mechanism 8 while the driven wheels 3, 4 are sequentially steered by the first steering mechanism 7 according to the turning radius. By rotating the drive wheels 5, 6 by driving the hydraulic motor 29 of the rotary drive mechanism 9, all the axles of the driven wheels 3, 4 and the drive wheels 5, 6 are always directed to the turning center. The turning radius can be turned smoothly. By rotating the pair of left and right driving wheels 5 and 6 via the differential gear 20 during this turning, it is possible to minimize the wear of the tire due to the rotation difference between the inner and outer wheels of the pair of driving wheels 5 and 6. .

Since the pair of left and right drive wheels 5 and 6 are configured to be steerable, it is not always necessary to set the steering state as shown in FIG. 8, but the steering angles of the front driven wheels 3 and 4 and the rear side The steering angles of the driven wheels 3 and 4 can be set independently, and the vehicle can turn while drawing a trajectory different from a simple arc trajectory, thereby significantly improving the turning traveling performance. According to the carrier 1, the front and rear ends of the carrier frame 2 are supported by a pair of left and right driven wheels 3 and 4, and the center of the carrier frame 2 in the front and rear direction is supported by drive wheels 5 and 6. The rigidity of the frame 2 can be reduced, and the size and weight of the bogie frame 2 can be reduced.

By reducing the size of the bogie frame 2, the height of the transport bogie 1 can be reduced and the center of gravity can be reduced, so that stable traveling can be realized. By reducing the weight of the bogie frame 2, for example, the output of the hydraulic motor 29 of the rotary drive mechanism 9 can be reduced, so that the manufacturing cost can be reduced and the fuel cost can be reduced. Further, since the load burden shared by each of the driven wheels 3, 4 and the driving wheels 5, 6 can be reduced, the wear of the tires of the driven wheels 3, 4 and the driving wheels 5, 6 can be suppressed as much as possible to extend the life. . Thus, the running cost can be kept low.

Next, a modified embodiment in which the carrier 1 is partially modified will be described. However, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 9, the transport trolley 1B is provided with a rotary drive mechanism 9A that drives the pair of drive wheels 5, 6 to rotate independently. 1
The pair of drive wheels 5 and 6 are directly connected to the output shafts (not shown) of the pair of hydraulic motors 29A of the rotary drive mechanism 9A, respectively. It is configured to be. According to the carrier 1B,
The same operation and effect as those of the above embodiment can be obtained.

As shown in FIG. 10, the transport vehicle 1C has one drive wheel 53 at the center in the vehicle width direction at the center in the front-rear direction of the vehicle frame 2, and
Is provided with a rotation drive mechanism 9B for driving the rotation.
Drive wheel 53 is directly coupled to the output shaft of the hydraulic motor 29B of the rotary drive mechanism 9B (not shown), steering Organization is provided for steering the driving wheel 53. When a pair of drive wheels is provided, it is necessary to independently drive the pair of drive wheels or provide a differential gear in order to suppress tire wear due to a rotation difference between the inner and outer wheels, but it is necessary to provide a central portion in the vehicle width direction. 1
By providing the two drive wheels 53, the configuration of the rotary drive mechanism 9B is simplified, and the wear of the tires of the drive wheels 53 due to the turning of the transport vehicle 1C can be suppressed. Other operations and effects similar to those of the above-described embodiment are exhibited .

As shown in FIG . 11, for example, a guide tape 50 (corresponding to a guiding portion) provided with magnetism is provided on the traveling path L of the transport trolley 1A in the container terminal substantially at the center of the width of the traveling path L. It is pasted along. On the lower surface side of the bogie frame 2, guide sensor 51 for detecting the guide tape 50 is provided with a pair before and after, the platform car 1A
Automatically travels along the guide tape 50 while detecting the guide tape 50 with the pair of guide sensors 51.
Each of the pair of guide sensors 51 has, for example, 16 Hall elements arranged in a row in the width direction of the guide tape 50.
Of the pair of front and rear guide sensors 51, the front guide sensor 51 is disposed near the front end of the bogie frame 2, and the rear guide sensor 51 is connected to the rear driven wheels 3 and 4 on the bogie frame 2. It is located near the axle. Transport cart 1A
Is the above-described carrier 1 except for the guide sensor 51.
It has almost the same configuration as.

Next, a description will be given of a guiding technique for guiding the carriage 1A along the guide tape 50. FIG.
As shown in FIG. 12, each of the pair of guide sensors 51 has one
When six hole elements 52 are provided and only the five hole elements 52 indicated by black circles detect the guide tape 50 and are turned ON, the carrier 1A based on the detection signals of the sixteen hole elements 52 The first steering mechanism 7, the second steering mechanism 8, and the rotation drive mechanism 9 are controlled by the control device such that the center line 1a of the vehicle body, that is, the center line of the pair of guide sensors 51 coincides with the center line 50a of the guide tape 50. I do.

For example, as shown in FIG. 13, when the guide tape 50 has a curved portion having a constant radius R and straight portions continuous at both ends of the curved portion, the carriage 1A is moved from the straight portion on one end to the curved portion. When the left turn guidance or the right turn guidance is performed, a drive signal is output to the hydraulic motor 29 based on the detection signals from the pair of guide sensors 51, and the rotation speed of the hydraulic motor 29 is controlled. 29 through the differential gear 20 to drive wheels 5, 6
And the steering angles of the driven wheels 3 and 4 and the drive wheels 5 and 6 are synchronized with the rotation speed of the hydraulic motor 29, and the axles of the driven wheels 3 and 4 and the axles of the drive wheels 5 and 6, respectively. Is determined so as to face the turning center of the carrier 1A.
Guides a left turn guide or a right turn guide from the straight portion on one end side to the curved portion.

As shown in FIG. 14, when the transport vehicle 1A is guided to turn left or right on a curved portion, the rotational driving force of the hydraulic motor 29 is driven via the differential gear 20 in the same manner as described above. The driving wheels 5 and 6 are independently transmitted to the wheels 5 and 6, respectively, and the driven wheels 3 and 4 are controlled in synchronization with the rotation speed of the hydraulic motor 29, and the driven angles of the driven wheels 5 and 6 are set to 0 degrees. The axles 3 and 4 and the axles of the drive wheels 5 and 6 are determined so as to face the turning center of the carrier 1A.
A guides left turn guidance or right turn guidance on the curved part.

As shown in FIG. 15, when the transport vehicle 1A is guided to turn left or right from the curved portion to the straight portion on the other end side, the rotational driving force of the hydraulic motor 29 is differentially changed in the same manner as described above. Independently transmitted to the driving wheels 5 and 6 via the gear 20, the steering angles of the driven wheels 3 and 4 and the driving wheels 5 and 6 are synchronized with the rotation speed of the hydraulic motor 29, respectively. Axle and drive axles 1 and 2
Is determined so as to face the turning center, and the transport vehicle 1A guides the left turn or the right turn from the curved portion to the straight portion on the other end side.

As described above, the axle of each of the driven wheels 3 and 4 and the axles of the drive wheels 5 and 6 in the vicinity of the entrance to the curved portion and the vicinity of the exit from the curved portion when the vehicle is turned, in particular, are set. By determining the steering angles of the driven wheels 3 and 4 and the steering angles of the drive wheels 5 and 6 so that all of them face the turning center of the transport vehicle 1A, the turning is smoothly guided. According to the transport trolley 1A, the same operation and effect as those of the above embodiment can be obtained.

Next, a description will be given of a modified example in which the carrier is partially changed. 1) Each driven wheel may be constituted by a single tire wheel. Since the drive wheels are provided at the center of the bogie frame 2 in the front-rear direction, the rigidity of the bogie frame 2 can be reduced, and the size and weight of the bogie frame 2 can be reduced. The operation and effect of are obtained. 2) Three or more driven wheels may be provided at both front and rear ends of the bogie frame 2 respectively. 3) Three or more drive wheels may be provided at the center of the bogie frame 2 in the front-rear direction, and these drive wheels may be configured to be driven independently, or may be connected via a differential gear.

4) The first steering mechanism 7 for steering each driven wheel and the second steering mechanism 8 for steering the drive wheels are provided with various types such as a rack and pinion type in addition to the hydraulic cylinder type as in the above-described embodiment. Are applicable. 5) Instead of the hydraulic motor driving the drive wheels, an electric motor, an engine, or the like can be applied. 6] The transport carts 1, 1A, 1B, and 1C transport the container C, but change the structure and the like of the truck frame 2 to transport, for example, heavy objects such as coils and slabs in a steelworks yard. The present invention can be applied as a truck or other various heavy load transporting trucks.

[0043]

According to the present invention, the front and rear ends of the bogie frame are supported by at least one pair of right and left driven wheels, and the front and rear central portions of the bogie frame are supported by drive wheels. Therefore, the rigidity of the bogie frame can be reduced, and the size and weight of the bogie frame can be reduced. The downsizing of the bogie frame makes it possible to lower the center of gravity of the heavy-duty carrier by lowering the height of the truck, thereby realizing stable running. As a result, the production cost and the fuel cost can be reduced, and the load shared by each wheel can be reduced, so that the wear of the driven wheels and the drive wheels can be minimized. As a result, the running cost of the heavy load transporting vehicle can be significantly reduced.

When the heavy object transporting vehicle is turning, the driving wheels are steered by the second steering means while the driven wheels are steered by the first steering means according to the turning radius, and the driving wheels are rotated by the driving of the rotary driving means. As a result, the heavy load transport vehicle can be turned. In particular, since the pair of left and right drive wheels provided at the center part in the front-rear direction of the bogie frame can be steered by the second steering means, it is not necessary to steer the steering angles of the front and rear follower wheels at the same time during turning. Increased freedom of travel,
Turning performance is improved.

[0045] Then, the drive wheel is provided with driving wheels a pair of left and right driven independent, independent drive wheels of the right-and-left
Is provided with a rotation driving means for driving the rotation of the heavy object transporting vehicle. When the heavy object transporting vehicle turns, the left and right driving wheels are independently driven to rotate in accordance with the turning radius, whereby the inner and outer wheels of the pair of driving wheels are rotated. Tire wear due to rotation difference can be minimized .

[0046] According to heavy transport carriage according to claim 2, drive rotation of the drive wheels of the right and left pair via the differential gear
Since a common rotating drive means is provided, a pair of left and right drive wheels are driven to rotate via a differential gear when the heavy load transport vehicle turns, so that a difference in rotation between the inner and outer wheels of the pair of drive wheels is provided. This minimizes tire wear. The other effects are the same as those of the first aspect.

According to the heavy object transporting cart of the third aspect , the first
The steering means is configured to be able to independently steer the plurality of driven wheels, and the second steering means is configured to be able to steer the drive wheels independently of the driven wheels. By steering the axles so as to be directed to the turning center of the heavy load transport vehicle, the heavy load transport vehicle can be turned smoothly. The other effects are the same as those of the first or second aspect .

According to the fourth aspect of the present invention , the heavy object transport vehicle has a guide sensor for detecting a guide portion formed along the traveling path, and the guide sensor detects the guide portion. Since it is configured to be able to automatically travel along the guide section, the heavy goods transport vehicle can automatically travel along the guide section while detecting the guide section with the guide sensor. The other effects are the same as those of the third aspect .

According to the heavy object transporting cart of claim 5, the cart is used.
One at the center in the vehicle width direction at the center in the front-rear direction of the frame
A driving wheel is provided, and one rotary drive for rotating the driving wheel is provided.
Moving means, so that the rotary drive
The structure of the step is simplified, and the tires of the drive wheels
Wear can be suppressed. Others similar to claim 1
It works.

[Brief description of the drawings]

FIG. 1 is a perspective plan view of a heavy object transporting truck according to an embodiment of the present invention.

FIG. 2 is a left side view of the heavy object transporting cart of FIG. 1;

FIG. 3 is a horizontal cross-sectional view of a main part in FIG. 1 of the heavy object transporting cart.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is an enlarged sectional view taken along line VV of FIG. 1;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 7 is a sectional view taken along line VII-VII of FIG. 6;

FIG. 8 is an explanatory view showing a turning state of the heavy object transporting cart.

FIG. 9 is a perspective plan view of a heavy object transporting truck according to another embodiment.

FIG. 10 is a perspective plan view of a heavy object transporting truck according to another embodiment.

FIG. 11 is a schematic plan view of a heavy object transporting truck according to another embodiment.

FIG. 12 is an explanatory diagram showing a positional relationship between a guide sensor and a guide unit of a heavy goods transporting truck according to another embodiment.

FIG. 13 is a diagram illustrating a first state in which the heavy object transporting trolley automatically turns.
It is explanatory drawing of a stage.

FIG. 14 illustrates a second state in which the heavy object transporting trolley performs automatic turning traveling.
It is explanatory drawing of a stage.

FIG. 15 shows a third state in which the heavy object transporting trolley performs automatic turning traveling.
It is explanatory drawing of a stage.

[Description of Signs] 1 , 1A, 1B, 1C transport cart 2 bogie frame 3, 4 driven wheel 5, 6 drive wheel 7 first steering mechanism 8 second steering mechanism 9 , 9A, 9B rotation drive mechanism 20 differential gear

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D034 CA03 CB03 CB06 CC01 CC02 CC08 CC12 CD18 CD20 CE01 5H301 AA02 BB05 CC03 DD01 DD15 EE03 EE06 GG28 HH01 HH15

Claims (5)

[Claims] 1. A heavy object transporting trolley for transporting a heavy object, comprising: a trolley frame for placing and supporting a heavy object; at least one pair of driven wheels provided on both front and rear ends of the trolley frame; A drive wheel provided at a central portion in the front-rear direction of the frame, first steering means for steering the plurality of driven wheels, rotary drive means for rotating the drive wheel, and second steering means for steering the drive wheel. And a heavy object transporting trolley comprising: 2. The heavy goods transport vehicle according to claim 1, wherein a pair of left and right drive wheels that are independently driven are provided as the drive wheels. 3. The heavy goods transport according to claim 1, wherein a pair of left and right drive wheels connected via a differential gear and driven by common rotary drive means are provided as the drive wheels. Trolley. 4. The apparatus according to claim 1, wherein the first steering means is configured to be able to independently steer a plurality of driven wheels, and the second steering means is configured to be able to steer a driven wheel independently of the driven wheels. The heavy goods transporting vehicle according to any one of claims 1 to 3, wherein 5. The heavy object transporting vehicle has a guide sensor for detecting a guide portion formed along a traveling path, and can automatically travel along the guide portion while detecting the guide portion with the guide sensor. The heavy goods transporting trolley according to claim 4, wherein the trolley is configured.