JPH0241474B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to improving the running characteristics of a transport vehicle.

[Prior art]

Conventionally, there have been devices of this type as shown in FIGS. 1 and 2.

FIG. 1 shows a bottom view of a conventional carrier, and FIG. 2 shows a front view. In the figure, 1 is a truck body, 2 is a wheel, 3 is a block fixed to the truck body 1 and supports rotation of the wheel 2, and 4 is a motor. Further, 5 is a mechanism section for transmitting the power of the motor 4 to the wheels 2, 6 is an auxiliary wheel fixed to the truck body 1, and 7 is a loading platform. In operation, the trolley body 1 is moved by transmitting the rotation of the two motors 4 to the wheels 2 via the power transmission mechanism 5. At this time, the auxiliary wheels 6 play the role of supporting the bogie main body 1 so as not to interfere with running. The transport vehicle can travel in two different ways: straight travel, which goes back and forth on the same straight line as the transport vehicle, and curve travel, fixed point turning, which is centered on a point on the extension of the rotation axis of the two wheels 2. It is roughly divided into two types: advancing and running. Figure 3 shows the straight forward movement of a conventional transport vehicle.
FIGS. 4 and 5 are explanatory diagrams showing the curved movement of a conventional transport vehicle. The arrow in the figure indicates the direction of movement of the carrier. Of these, for straight travel, two motors 4
This can be carried out by driving the two wheels 2 and synchronously rotating them in the same direction at the same rotational speed via the power transmission mechanism 5. In addition, during curved travel, the two motors are operated so that the distance between the two wheels 2 and the center of curvature of the traveling trajectory of the transport vehicle and the rotational speed ratio of each of the two wheels 2 are in a constant relationship. This can be carried out by controlling the rotation of 4.

Conventional transport carts are configured as described above, so even if you want to move the cart horizontally or diagonally by a small distance in parallel, for example, you have to move the cart in a complicated manner such as combining curved movement and straight movement. It is necessary to execute a series of sequences, and as a result, the direction of the transport vehicle changes several times, which has the disadvantage that it cannot always be aligned with the original direction. Furthermore, more space was required for movement than would have been expected if it were simply shifted laterally and in parallel.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and includes a plurality of rotating members supported by a bogie body and rotatable in a plane parallel to the running surface of the bogie, and each of these rotating members. A detection means for detecting the amount of rotation with respect to the bogie body is attached to each of the rotating members so that their respective rotation axes are the same and parallel to the bogie running surface, and
By providing two drive wheels whose rotations can be controlled independently, and a control means for controlling the rotational speed of each of the drive wheels based on the signal output from the detection means, the traveling direction and the conveyance can be controlled. The purpose of the present invention is to provide a transport vehicle that can move accurately in a desired direction, such as horizontally or diagonally, by continuously and freely controlling the direction of the vehicle.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 6 is a bottom view of a carrier according to an embodiment of the present invention, and FIG. 7 is a sectional view taken along the line -- in FIG. 6.

In the figure, reference numerals 8 and 9 are rotary members supported by the truck body 1, and for example, two rotary members are provided on the axis of line symmetry of the truck body 1 at equal distances from the center.
Reference numerals 10 and 11 designate bearings whose inner rings are fitted into the rotating members 8 and 9, and whose outer rings are fitted into the truck body 1, and the rotating members 8 and 9 are rotatable in a plane parallel to the truck running surface. 12 and 13 are rotating members 8
Further, reference numerals 14 and 15 are drive wheels that are attached to the rotating member 9 and can be rotated independently by dedicated motors 41, 42, 43, and 44, respectively. The rotation of the driving wheels 12, 13, 14, 15 is controlled by the motors 41, 42, 43, 44 by a control means (not shown).
By controlling each of them, the rotation speed can be controlled independently. Further, the driving wheels 12 and 13 attached to the rotating member 8 have rotating shafts on the same straight line parallel to the running surface of the bogie, and this rotating shaft is connected to the rotating member 8.
It rotates in a plane parallel to the bogie running surface as the bogie rotates. The same applies to the rotating member 9. 16,1
Reference numeral 7 denotes a detection means for detecting the amount of rotation of the rotating members 8 and 9 relative to the truck body 1 via measuring gears 18 and 19 and 20 and 21, which in this case is a rotary encoder.

The operation will be explained below. The rotating member 8 is
Drive wheels 12, 13 attached to the same rotating member
By rotating them in opposite directions and synchronously at the same rotational speed, it is possible to rotate them within the bearing 10 without applying any external force to the carrier body 1. Along with this, the directions of the drive wheels 12 and 13 can also be changed with respect to the truck body 1. At this time, since the rotation amount of the rotating member 8 is constantly detected by the rotary encoder 16 via the measuring gears 18 and 19, the control means controls each motor 41 and 42 based on the signal output from the rotary encoder 16. It is possible to accurately control the amount of rotation of the rotating member 8 by controlling.

FIG. 8 is a block diagram showing the control operation of the control means according to an embodiment of the present invention, where 22 indicates the amount of rotation of the rotating member 8 detected by the rotary encoder 16 at a detection angle. 23 is the reference angle,
Indicates the rotation angle in the target direction. 24 and 25 are a subtracter and a multiplier, respectively, which determine the deviation of the amount of rotation of the rotating member 8 from the target direction. 26 is the reference speed, 27
28 indicates the motor 41 speed command, and 28 indicates the motor 42 speed command, so that the rotating member 8 faces the target direction.
A command is issued to give a deviation to the rotational speed of each of the motors 41 and 42.

Similarly, the rotating member 9 can be accurately rotated by any amount of rotation.

In this way, by accurately rotating the rotating members 8 and 9 by the desired amount of rotation, the drive wheel 1
2, 13, 14, and 15 can be accurately directed in the desired direction.

FIG. 9 is an explanatory diagram showing the movement locus of the carrier according to an embodiment of the present invention. For example, as shown in the figure, when the carrier is moved in a direction at an angle α with respect to the direction of the carrier body 1, In the above method,
After rotating the rotating members 8 and 9 by α and directing all the drive wheels 12, 13, 14, and 15 in the direction of the angle α, the drive wheels 12, 13, 14, and 15
By rotating in the same direction and synchronously at the same rotational speed, it is possible to move the carrier carriage in the direction of the angle α without changing the orientation of the carriage body 1. During this movement, if either of the drive wheels 12 or 13 loses synchronization between the moving speeds of the drive wheels 12 and 13 due to a disturbance such as slipping due to a bad running surface of the bogie, the rotating member 8 Rotates easily, driving wheels 12, 13 are oriented at an angle α
It deviates from the For this reason, the trolley body 1
It is expected that the vehicle will not be able to move the vehicle in the direction of the angle α or that it will not be possible to drive stably. However, this angle deviation is caused by the measurement gear 1
Since the rotary encoder 16 constantly detects the angle shift via the drive wheels 12 and 19, even if such an angular shift occurs, the control means will control the drive wheels 12 and 19.
By giving a deviation to the rotational speed of the rotating member 13, the direction of the rotating member 8 can be immediately returned to the direction of the angle α. Drive wheels 14, 15, rotating member 9, measuring gears 20, 21, rotary encoder 1
7 can be similarly controlled.

In this way, when the carrier is moved, the deviation of the directions of the rotating members 8 and 9 from the intended movement direction is minimized, so that the carrier can be accurately moved in the desired direction.

Furthermore, since each of the drive wheels 12, 13, 14, and 15 has a function of performing steering control and a function of performing travel control, it is possible for each drive wheel to perform steering control and travel control at the same time. Therefore, for example, a transition from straight-ahead travel to curved travel, and then to straight-ahead travel can be continuously realized by applying substantially the same control to each drive wheel. Therefore, unnecessary control can be suppressed compared to a transport vehicle that performs travel control and steering control separately and discontinuously.

〔Effect of the invention〕

As described above, according to the present invention, a plurality of rotating members are supported by the truck body and are rotatable in a plane parallel to the truck running surface, and a detection means for detecting the amount of rotation of each of these rotating members with respect to the truck body. ,
Two driving wheels are attached to each of the rotating members so that their rotating shafts are the same and parallel to the bogie running surface, and whose rotations can be controlled independently, and a signal output from the detecting means. Since it is originally equipped with a control means for controlling the rotational speed of each of the drive wheels, it is possible to move accurately and stably in any direction, and furthermore, each drive wheel can perform steering control and travel control at the same time. As a result, it is possible to obtain a conveyance vehicle that can continuously realize running such as, for example, moving from straight running to curved running, and then further shifting to straight running.

[Brief explanation of drawings]

FIGS. 1 and 2 are a bottom view and a front view of a conventional transport vehicle, respectively, FIG. 3 is an explanatory diagram showing the straight trajectory of the conventional transport vehicle, and FIGS. 4 and 5 are:
FIG. 2 is an explanatory diagram showing a curved trajectory of a conventional transport vehicle.
6 and 7 are respectively a bottom view and a cross-sectional view taken along the line -- of FIG. 6 of a transport vehicle according to an embodiment of the present invention, and FIG. 8 shows a control operation of a control means according to an embodiment of the present invention. The block diagram shown in FIG. 9 is an explanatory diagram showing a movement locus of a transport vehicle according to an embodiment of the present invention. 1... Cart body, 8, 9... Rotating member, 12,
13, 14, 15... Drive wheel, 16, 17...
Detection means. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A plurality of rotating members supported by the truck body and rotatable in a plane parallel to the truck running surface, a detection means for detecting the amount of rotation of each of these rotating members with respect to the truck body, and a detection means for detecting the amount of rotation of each of the rotating members with respect to the truck body. two drive wheels that have the same shaft and are mounted so that they are parallel to the bogie running surface, and whose rotations can be controlled independently; A transport vehicle equipped with a control means for controlling the rotation speed of the transport vehicle.