JP2007004374A - Conveying vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent slip of driving wheels and application of an excessive load on a body of a conveying vehicle due to difference in curvature of tracks, on which the respective wheels are positioned, in a conveying vehicle equipped with a plurality of driving wheels and guided by tracks having different curvature parts for traveling through a predetermined travel route. <P>SOLUTION: This conveying vehicle is provided with respective drivers (inverters 34 and 35), which control the respective driving wheels 4 and 5, and a control means. By means of the control means, the same instruction value is given to the respective drivers when both of the driving wheels 4 and 5 are positioned on the parts with the same curvature on the tracks, while instruction values according to the curvatures is given to the respective drivers when the respective driving wheels 4 and 5 are positioned in the parts with different curvatures. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transport vehicle that travels along a predetermined travel route, and more specifically, a plurality of drive wheels disposed at intervals in the vehicle body traveling direction are guided by a track having portions with different curvatures to perform a predetermined travel. The present invention relates to a transport vehicle that travels along a route.

  2. Description of the Related Art Conventionally, in order to perform automatic article conveyance work in a factory or the like, for example, a conveyance vehicle system in which an unmanned conveyance vehicle configured to transfer an article on a predetermined traveling route has been used. A transport vehicle in such a transport vehicle system generally has a configuration in which travel wheels including a drive wheel are guided on a track made of rails or the like on a travel route. Some of the drive wheels of the transport vehicle are driven by a motor provided in the transport vehicle, and electric power is supplied to the motor from a power supply line attached along the travel route. And in order to obtain the desired driving force of a conveyance vehicle, there exists a conveyance vehicle of the structure provided with several drive wheels guided to a track | orbit.

In this way, when the transport vehicle has a plurality of drive wheels guided on a track such as a rail as traveling wheels, each drive wheel is controlled so that its torque and speed are the same. That is, in the conventional transport vehicle, a motor for driving each drive wheel is connected in parallel to a single driver, and each motor is controlled by the same command value from this driver.
Moreover, although the technique about the overhead traveling vehicle which travels along a rail is disclosed in Patent Document 1, in this document, traveling wheels (drives) provided respectively to at least a pair of carriages constituting the overhead traveling vehicle. A motor for driving each of the wheels is provided. A driver for controlling each motor is provided for each motor, and the same drive current is supplied from each driver to each motor, so that the output torque of each motor is equalized. Thereby, each motor which drives each drive wheel is controlled by the same command value.
JP-A-9-301675

  By the way, in the conveyance vehicle as described above, when a track such as a rail that guides the drive wheels has a portion with a different curvature, a state in which the curvature of the track on which each drive wheel is located is different. When the transport vehicle travels in such a state, since the relative positional relationship of each drive wheel in the transport vehicle is constant, the required speed (number of rotations) for each drive wheel is different. . However, conventionally, since the command values for the drive wheels are the same as described above and the drive wheels have substantially the same speed, the following problems have occurred.

  That is, as the case where the curvature of the portion where each driving wheel is located on the track is different, for example, a transport vehicle having front and rear driving wheels guided by the rail enters the curved portion from the linear portion of the rail, and the front side When the driving wheel (front driving wheel) is located on the curved portion of the rail and the rear driving wheel (rear driving wheel) is located on the linear portion of the rail, the relative positional relationship between the front and rear driving wheels in the transport vehicle is Since it is constant, there will be a difference in the amount of movement of the front and rear drive wheels. In this case, if the command values for the front and rear drive wheels are the same, there is a discrepancy between the command value and the actual amount of movement of the drive wheels. In other words, in this case, if a command value that matches the amount of movement of the rear drive wheel located at the straight line portion is used, the amount of movement of the front drive wheel located at the curved portion will be insufficient. If a command value that matches the amount of movement of the front driving wheel that is positioned is used, the amount of movement of the rear driving wheel that is positioned in the straight line portion becomes redundant.

  Such discrepancy between the command value and the actual amount of movement in the drive wheels may cause slippage of the drive wheels guided by a track such as a rail, or may cause an unreasonable load on the vehicle body of the transport vehicle. To do. Such a slip of the driving wheel and a load applied to the transporting vehicle are not preferable in a transporting vehicle system that requires high accuracy in order to transfer and unload articles in a factory or the like.

  Accordingly, the problem to be solved by the present invention is that each drive wheel is located in a transport vehicle having a plurality of drive wheels, which are guided by a track having portions with different curvatures and travel along a predetermined travel route. This is to prevent an excessive load from being applied to the slip of the drive wheels and the body of the transport vehicle due to the difference in the curvature of the track.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in the first aspect of the present invention, the transport vehicle includes a plurality of drive wheels disposed at intervals in the vehicle body traveling direction, and travels along a predetermined travel route guided by a track having portions with different curvatures. When each of the individual drivers for controlling each of the driving wheels and each of the driving wheels are located at the same curvature portion in the track, the same command value is given to each of the drivers, And a control means for giving a command value corresponding to the curvature to each driver when located in a portion of a different curvature in the trajectory.

  According to a second aspect of the present invention, a current position recognizing unit for recognizing a current position of each driving wheel, and a storage unit for command value information that is a table of the command value at each position of the trajectory, the control unit includes: The command value to be given to each driver is specified based on the current position of each drive wheel recognized by the current position recognition means and the command value information.

  In Claim 3, The present position recognition means which recognizes the present position of each said driving wheel, The memory | storage means which memorize | stores the driving | running route information which is a table of the curvature in each position of the said track, The present position of each said driving wheel Command value calculating means for calculating a command value for each driver in accordance with the difference in curvature of the track at the current position, wherein the command value calculating means is a current value of each driving wheel recognized by the current position recognizing means. The command value is calculated on the basis of the position and the travel route information, and the control means gives the calculated command value to each driver.

  As effects of the present invention, the following effects can be obtained.

  In claim 1, when each drive wheel is located in a portion of a different curvature in the track, a speed command value corresponding to the actual movement amount can be given to each driver. It is possible to make the command value coincide with the actual movement amount of each drive wheel in the track. Thereby, it is possible to prevent an excessive load from being applied to the slip of each driving wheel guided on the track and the vehicle body of the transport vehicle.

  In claim 2, the control means recognizes the current position of each drive wheel in the track by the current position recognition means, and specifies from the command value information (table) in which the command value at that position is stored. Each drive wheel can be controlled with an optimum command value in accordance with the curvature of the portion where the drive wheel is located. As a result, it is possible to reliably prevent slippage of each drive wheel and an unreasonable burden on the vehicle body of the transport vehicle according to the shape of the track.

  According to the third aspect of the present invention, each drive wheel can be controlled by an optimum command value calculated according to the difference in curvature of the portion where each drive wheel is located on the track. As a result, it is possible to reliably prevent slippage of each drive wheel and an unreasonable burden on the vehicle body of the transport vehicle according to the shape of the track.

Next, embodiments of the invention will be described.
First, the structure of the conveyance vehicle which concerns on this invention is demonstrated using FIGS. 1-3. FIG. 1 is a plan view showing the configuration of a transport vehicle according to the present invention, FIG. 2 is a rear view, and FIG. 3 is a side view.
The transport vehicle 1 according to the present invention, for example, in a factory or the like, automatically performs an article transport operation, so that a transport vehicle system in which an unmanned transport vehicle configured to be able to transfer an article travels on a predetermined travel route. Is used.
That is, the transport vehicle 1 in this embodiment includes a front drive wheel 4 and a rear drive wheel 5 as a plurality of drive wheels disposed at intervals in the vehicle body traveling direction, and these drive wheels 4 and 5 have different curvatures. The vehicle travels along a predetermined travel route by being guided by a rail 2 as a track having a portion.

The transport vehicle 1 has a plate-like member having a substantially square shape in plan view as a vehicle body 6, and has a transfer device 7 formed on the vehicle body 6 by, for example, a chain conveyor. An article 9 is placed on the transfer device 7 via a pallet 8 or the like, and the article 9 is transferred by the transport vehicle 1 on a predetermined travel route. In addition, illustration of the transfer apparatus 7 is abbreviate | omitted in FIG.
The transport vehicle 1 includes a front drive wheel unit 14 having a front drive wheel 4 and a rear drive wheel unit 15 having a rear drive wheel 5 on the bottom surface side of the vehicle body 6. In FIG. 3, the driving wheel units 14 and 15 are not shown.

As shown in FIGS. 1 and 2, each of the drive wheel units 14 and 15 is disposed at a predetermined interval along one side of the substantially square-shaped vehicle body 6, and on the other side of the vehicle body 6. The caster wheels 10 and 11 as auxiliary wheels are disposed so as to be horizontally turnable at a predetermined interval. That is, in this embodiment, the transport vehicle 1 includes a front drive wheel 4 guided to the rail 2 in the front drive wheel unit 14, a rear drive wheel 5 guided to the rail 2 in the rear drive wheel unit 15, It is supported at four points by caster wheels 10 and 11 that support the vehicle body 6 with respect to the floor surface 3.
Here, in order to reduce the portion of the curvilinear portion of the rail 2 where the vehicle body 6 of the transport vehicle 1 protrudes from the rail 2, the drive wheel units 14 and 15 guided by the rail 2 are arranged on one side of the vehicle body 6. The rail 2 is arranged so as to be on the outer side in a travel route configured in a loop shape.

  Each of the drive wheel units 14 and 15 has a hollow square columnar bracket 21 provided on the bottom surface of the vehicle body 6 so as to be horizontally rotatable, and a rotary shaft (not shown) provided in each bracket 21 in the horizontal direction. ) Through which the front drive wheel 4 and the rear drive wheel 5 are provided. That is, in the front drive wheel unit 14, the front drive wheel 4 covered by the bracket 21 is guided by the rail 2 in a state of being mounted on the rail 2, and in the rear drive wheel unit 15, after being covered by the bracket 21. The drive wheel 5 is covered by the bracket 21 and is guided by the rail 2 in a state of being mounted on the rail 2.

Further, the drive wheel units 14 and 15 are arranged so that each drive wheel 4 and 5 travels along the center line of the rail 2 (the posture (traveling direction) of each drive wheel 4 and 5 is tangential to the rail 2). Guide rollers 23 and 23 for guiding the drive wheel units 14 and 15 with respect to the rail 2 are provided.
The guide rollers 23 and 23 are rotatably provided on the left and right sides of the rail 2 via a support shaft 22 provided in a direction perpendicular to the bracket 21. In other words, the lower portion of the bracket 21 is formed with flange portions 21 a that protrude on both sides in the width direction of the rail 2, and the support shaft 22 is provided in the vertical direction on the flange portion 21 a, and the guide shaft 22 is guided through the support shaft 22. Rollers 23 and 23 are provided so as to contact both side surfaces of the rail 2.
In this embodiment, one set of guide rollers 23 and 23 is provided before and after each drive wheel 4 and 5 in each drive wheel unit 14 and 15, and each drive wheel unit 14 and 15 has two sets of guides. It has rollers 23 and 23, that is, a total of four guide rollers 23 (see FIG. 1).

Each drive wheel unit 14 and 15 has motors 24 and 25 for rotationally driving the respective drive wheels 4 and 5, and each motor 24 and 25 has a rotation axis in a substantially horizontal direction. The bracket 21 is fixed from the side. That is, in the front drive wheel unit 14, the front drive wheel 4 is driven by the motor 24, and in the rear drive wheel unit 15, the rear drive wheel 5 is driven by the motor 25.
With such a configuration, each of the drive wheel units 14 and 15 is provided so as to be able to turn horizontally with respect to the vehicle body 6 as a whole, and can travel on the curved portion of the rail 2 of the transport vehicle 1. That is, each drive wheel unit 14/15 is provided with each drive wheel 4/5, each motor 24, 25, etc. on a bracket 21 provided so as to be horizontally turnable with respect to the vehicle body 6, and these are integrated with the vehicle body. 6 is configured to be able to turn horizontally. As a result, the drive wheels 4 and 5 are guided to the rail 2 together with the drive wheel units 14 and 15, and the drive wheels 4 and 5 are connected to the rail 2 even when the transport vehicle 1 is located on the curved portion on the rail 2. Following the shape of the vehicle, traveling in the curved portion of the transport vehicle 1 is performed.

In addition, power is supplied to the transport vehicle 1 by a non-contact power feeding system that supplies power in a non-contact manner using electromagnetic induction. This non-contact power supply system includes a primary side circuit including a power supply device (not shown) and a power supply line 16 and the like, and a secondary side circuit (not shown) to which the motors 24 and 25 of the transport vehicle 1 are connected. These primary circuit and secondary circuit are provided in a non-contact state. As shown in FIG. 2, the power supply line 16 is attached along the rail 2 and receives supply of alternating current from the power supply device. Then, the induced electromotive current is taken out from the magnetic field generated in the feeder line 16 by the supplied current in a non-contact manner, and the induced electromotive current is converted into a predetermined voltage by the secondary side circuit. 15 is supplied to motors 24 and 25 to drive both motors 24 and 25.
The power supply to the transport vehicle 1 is not limited to the non-contact power supply system, and power may be supplied from a trolley wire or a battery may be mounted on the transport vehicle 1. Here, when a trolley wire is used, a trolley wire is arranged instead of the feeder line 16, a current collector is provided in the transport vehicle 1, and electric power obtained by the current collection is supplied to the motors 24 and 25.

With the configuration as described above, the motors 24 and 25 of the drive wheel units 14 and 15 are driven by the electric power supplied via the feeder line 16, and the front and rear drive wheels 4 and 5 are respectively driven. The front and rear drive wheels 4 and 5 disposed on one side of the vehicle 6 are guided by the rail 2 and the other side of the vehicle body 6 is supported by the caster wheels 10 and 11 so that the transport vehicle 1 is in a predetermined travel route. Drive on.
In addition, although the conveyance vehicle 1 of this embodiment demonstrated above is the structure which drive | works along the rail 2 laid on the floor surface 3, it is not limited to this, For example, it arrange | positions on a ceiling. Any transport vehicle that travels along a predetermined travel route, such as an overhead traveling vehicle traveling along a rail, may be used.

Then, the control structure of the conveyance vehicle 1 which concerns on this invention is demonstrated using FIG. FIG. 4 is a block diagram showing the control mechanism of the transport vehicle according to the present invention.
The transport vehicle 1 configured as described above and guided on the rail 2 and traveling on a predetermined travel route includes an individual driver for controlling the front and rear drive wheels 4 and 5 and each of the drive wheels 4 and 5. The same command value is given to each driver when positioned in the same curvature portion of the rail 2, and when each drive wheel 4, 5 is positioned in a different curvature portion of the rail 2, the driver is in accordance with the curvature. And a control means for giving a command value.

  As shown in FIG. 4, the transport vehicle 1 includes a control unit 31 that controls the travel of the transport vehicle 1, and the control unit 31 receives a signal from a main controller 30 provided in the vicinity of the travel route and transports the transport vehicle 1. The car 1 is controlled. That is, the main controller 30 and the control unit 31 of the transport vehicle 1 are configured to be able to transmit signals to each other via, for example, a communication cable or a wireless transmission / reception device. When the transport command is transmitted to the transport vehicle 1 on the second position, the transport vehicle 1 receives the transport command, moves to a predetermined position on the rail 2 in accordance with the transport command, and transfers the article.

Based on the external command from the main controller 30 as described above and detection signals from various sensors provided in the transport vehicle 1, the control unit 31 drives the motors 24 and 25 that drive the drive wheels 4 and 5, and the transfer unit. The drive of the motor etc. which drive the mounting apparatus 7 is managed and controlled.
For each drive wheel 4, 5, the control unit 31 integrates the speed calculation unit that calculates the speed of the front and rear drive wheels 4, 5 in the transport vehicle 1 and the speed calculated by the speed calculation unit 4. A position calculation unit that calculates the position of the rail 5 on the rail 2 is provided, and the target value of the drive current of each of the motors 24 and 25 is determined with reference to the calculated speed and position.
That is, an encoder 44 is provided for the motor 24 that drives the front drive wheel 4, and an encoder 45 is provided for the motor 25 that drives the rear drive wheel 5 (see FIG. 1). Thus, the rotation speed of each motor 24, 25, that is, the rotation speed of the motor shaft of each motor 24, 25, is detected, and the speed and position (travel distance) of each drive wheel 4, 5 are detected by the control unit 31 based on this detection signal. ) Is calculated.

Specifically, the encoders 44 and 45 detect pulse signals that are output every time the motor shafts of the motors 24 and 25 rotate by a predetermined angle. The encoders 44 and 45 detect the rotation speeds of the motor shafts of the motors 24 and 25 by detecting the interval (cycle) of the pulse signals, and count the pulse signals to detect the motor shafts 24 and 25. The number of rotations of the motor shaft is detected.
Here, the detection signals from the encoders 44 and 45 are input to the control unit 31, converted into the speeds of the drive wheels 4 and 5 by the speed calculation unit, and the speeds are integrated by the position calculation unit. It is converted into the travel distance of the drive wheels 4 and 5, that is, the travel distance of the transport vehicle 1. Thereby, the control part 31 recognizes the speed and the travel distance of each drive wheel 4 * 5. The travel distance may be obtained from the relationship between the number of pulses detected by the encoders 44 and 45 and the diameter of the drive wheels 4 and 5. Here, the diameters of the drive wheels 4 and 5 may be designed values, for example, may be fixed values, or may be fluctuating values in which the diameters change depending on the travel distance.
With such a configuration, the travel distance of each drive wheel 4 or 5 from a predetermined reference position on the rail 2 is recognized, and the current position on the rail 2 of each drive wheel 4 or 5 is recognized. It becomes. That is, the configuration including the encoders 44 and 45 and the control unit 31 is current position recognition means for recognizing the current position of each drive wheel 4 and 5 in the rail 2.

The control unit 31 is connected to inverters 34 and 35 as individual drivers for controlling the front and rear drive wheels 4 and 5 described above. Electric power is supplied to the motor 24 by the inverter 34 and the motor 24 is While being controlled, electric power is supplied to the motor 25 by the inverter 35 to control the motor 25. That is, the control unit 31 directly controls the inverters 34 and 35 as individual drivers, and gives each inverter 34 and 35 a command value corresponding to the current position in the rail 2 of each drive wheel 4 and 5. The motors 24 and 25 are indirectly controlled.
The inverters 34 and 35 are provided with current sensors (not shown) for measuring output currents (load currents (drive currents) of the motors 24 and 25), respectively. The load current is monitored and fed back to the inverters 34 and 35 to control the motors 24 and 25.

Thus, for the inverters 34 and 35 as individual drivers for controlling the front and rear drive wheels 4 and 5, respectively, the control unit 31 provides command values corresponding to the current positions of the drive wheels 4 and 5 on the rail 2. It functions as a control means that gives In other words, in the transport vehicle 1 according to the present invention, if each drive wheel 4 or 5 is located at a portion of a different curvature in the rail 2, the control is performed on each drive wheel 4 or 5 with a different command value. It has become.
The control unit 31 and the inverters 34 and 35 as drivers in the above control configuration are stored in the control panel 12 provided on the lower surface side of the vehicle body 6 in the transport vehicle 1 (see FIG. 3).

With such a configuration, when the drive wheels 4 and 5 are located at different curvature portions in the rail 2, the actual movement is performed as a command value corresponding to the current position in the rail 2 for each of the inverters 34 and 35. Since the command value of the speed according to the amount can be given, the command value for each driving wheel 4 and 5 and the actual movement amount of each driving wheel 4 and 5 on the rail 2 can be matched, It is possible to prevent slipping of the guided drive wheels 4 and 5 and an excessive load on the vehicle body 6 of the transport vehicle 1.
In this specification, the “curvature” means a curvature in a planar view shape of a set of center points in the width direction of the rail 2 (center line of the rail 2).

Further, by providing inverters 34 and 35 as drivers for the motors 24 and 25 for driving the drive wheels 4 and 5, respectively, torque-oriented control such as vector control is provided for the motors 24 and 25, for example. It can be performed. Thereby, the torque in the low speed range of the motors 24 and 25 can be improved.
That is, when a plurality of motors are controlled and driven by a single driver, the motor control method is limited to so-called V / F control for controlling the ratio between the output power and the output frequency of the inverter constituting the driver as a predetermined value. However, there is a problem that the driving force in the low speed range of the motor is insufficient. However, by providing a driver for each motor, the shortage of torque in the low speed range of the motors 24 and 25 is solved. Therefore, even when the article 9 transferred by the transport vehicle 1 is a heavy object, it is possible to improve the control response. Accordingly, it is possible to start the rail 2 of the transport vehicle 1 satisfactorily, so that the transport workability can be improved. Further, since the torque in the low speed range of the motors 24 and 25 can be improved, the motor capacity can be reduced.

  Hereinafter, a specific example of control according to the current position of the drive wheels 4 and 5 on the rail 2 will be described. In the following, as shown in FIG. 5, as a part of the rail 2, a substantially semicircular curved portion 2b having the same curvature and both ends of the curved portion 2b are connected and arranged substantially in parallel. A case will be described in which a portion having an inlet straight portion 2a and an outlet straight portion 2c is used, and the transport vehicle 1 travels while the front driving wheel 4 and the rear driving wheel 5 are guided in the rail 2 portion. That is, as shown in FIGS. 3A to 3E, the control in the process until the transport vehicle 1 traveling on the inlet straight portion 2a passes the curved portion 2b and travels on the outlet straight portion 2c will be described. .

First, the first embodiment will be described.
In the present embodiment, based on the current position in the rail 2 of each of the drive wheels 4 and 5 recognized by the current position recognition means and the command value information that is a table of command values at each position of the rail 2, The command value given to each inverter 34 and 35 is specified.

  That is, the command value information corresponds to the position of the drive wheels 4 and 5 on the rail 2, and the command value that does not cause the drive wheels 4 and 5 to slip (the rail 2 of the drive wheels 4 and 5). Is a table of speed command values in accordance with the actual movement amount. This command value is obtained in advance according to the amount of movement of each drive wheel 4 or 5 in the rail 2 from the relative relationship of the curvature of the portion of the rail 2 where each drive wheel 4 or 5 is located. This command value information is stored in the control unit 31. That is, the control unit 31 functions as a storage unit that stores the travel route information.

Specifically, the command value information when the transport vehicle 1 travels the portion of the rail 2 as shown in FIG. 5 includes five types of command values OD1 corresponding to the current positions of the drive wheels 4 and 5 on the rail 2. It becomes like the table shown in FIG. The command values OD1 to OD5 are combinations of command values for the drive wheels 4 and 5 (respective inverters 34 and 35). For example, the command value OD1 is a command value FOD1 for the front drive wheels 4 (inverter 34) and It consists of a command value ROD1 for the rear drive wheel 5 (inverter 35).
When explaining in order according to FIG. 5, first, as shown in FIG. 5A, the transport vehicle 1 is located at the entrance straight portion 2a, and the front and rear drive wheels 4 and 5 are both located at the entrance straight portion 2a. The current position recognizing means recognizes that each of the drive wheels 4 and 5 is located at the entrance straight portion 2a. A command value OD1 is specified from the command value information as a command value to be given to the inverters 34 and 35 based on the current positions of the drive wheels 4 and 5, and the command value FOD1 is assigned to the front drive wheels 4 A command value ROD1 is given to each of the drive wheels 5.
That is, in this case, since the curvature of the rail 2 where the drive wheels 4 and 5 are located is 0, the command value FOD1 and the command value ROD1 are the same value. The same command value is given to 34 and 35.

When the transport vehicle 1 travels and a part of the transport vehicle 1 reaches the curved portion 2b as shown in FIG. 5B, the front drive wheel 4 is positioned on the curved portion 2b, and the rear drive wheel 5 enters the entrance. It will be located in the straight line part 2a. In this case, it is recognized by the current position recognizing means that the front drive wheel 4 is located at the curved portion 2b and the rear drive wheel 5 is located at the inlet straight portion 2a. A command value OD2 is specified from the command value information as a command value to be given to the inverters 34 and 35 based on the current positions of the drive wheels 4 and 5, and the command value FOD2 is applied to the front drive wheels 4 after the rear drive. A command value ROD2 is given to each of the wheels 5.
That is, in this case, the curvature of the rail 2 where the drive wheels 4 and 5 are located is different, and the curvature of the inlet straight portion 2a where the rear drive wheel 5 is located is 0, whereas the front drive wheel 4 is located. Since the curved portion 2b has a curvature, the command value FOD2 and the command value ROD2 are different values. The command value OD2 has a larger movement amount in the front drive wheel 4 than in the rear drive wheel 5. Thus, different command values are given to the inverters 34 and 35.

Next, when the transport vehicle 1 further proceeds and the transport vehicle 1 is positioned at the curved portion 2b as shown in FIG. 5C, both the front and rear drive wheels 4 and 5 are positioned at the curved portion 2b. The current position recognizing means recognizes that each of the drive wheels 4 and 5 is located on the curved portion 2b. A command value OD3 is specified from the command value information as a command value to be given to the inverters 34 and 35 based on the current position of each drive wheel, and the command value FOD3 is given to the rear drive wheel 5 for the front drive wheel 4. On the other hand, a command value ROD3 is given.
In other words, in this case, since the curvature of the rail 2 where the drive wheels 4 and 5 are located is the curvature of the curved portion 2b, the command value FOD3 and the command value ROD3 are the same value, and the command value OD3 The same command value is given to each of the inverters 34 and 35.

Further, when the transport vehicle 1 further proceeds and a part of the transport vehicle 1 reaches the exit straight portion 2c as shown in FIG. 4D, the front drive wheel 4 is positioned at the exit straight portion 2c, and the rear The drive wheel 5 will be located in the curved part 2b. In this case, it is recognized by the current position recognizing means that the front drive wheel 4 is located at the outlet straight portion 2c and the rear drive wheel 5 is located at the curved portion 2b. A command value OD4 is specified from the command value information as a command value to be given to the inverters 34 and 35 based on the current positions of the drive wheels 4 and 5, and the command value FOD4 is applied to the front drive wheels 4 after the rear drive. A command value ROD4 is given to each of the wheels 5.
That is, in this case, the curvature of the rail 2 where the driving wheels 4 and 5 are located again is different, and the curvature of the exit straight portion 2c where the front driving wheel 4 is located is 0, whereas the rear driving wheel 5 Since the curved portion 2b in which the position is located has a curvature, the command value FOD4 and the command value ROD4 are different from each other. The command value OD4 moves in the front driving wheel 4 rather than in the rear driving wheel 5. Different command values are given to the inverters 34 and 35 so as to reduce the amount.

When the transport vehicle 1 further advances and the transport vehicle 1 is positioned at the exit straight portion 2c as shown in FIG. 5E, both the front and rear drive wheels 4 and 5 are positioned at the exit straight portion 2c. The current position recognizing means recognizes that each of the drive wheels 4 and 5 is located at the exit straight portion 2c. The command value OD5 is specified from the command value information as the command value to be given to the inverters 34 and 35 based on the current positions of the drive wheels 4 and 5, and the command value FOD5 for the front drive wheel 4 is the rear drive. A command value ROD5 is given to each of the wheels 5.
In other words, in this case, since the curvature of the rail 2 at the portion where each of the drive wheels 4 and 5 is located is 0, the command value FOD5 and the command value ROD5 are the same value. The same command value is given to 34 and 35.

  Thus, based on the command value information which is a table of command values obtained in advance according to the amount of movement of each drive wheel 4 or 5 in the rail 2 according to the current position of each drive wheel 4 or 5 in the rail 2. By specifying the command values for the inverters 34 and 35, the drive wheels 4 and 5 can be controlled with the optimum command values according to the curvature of the portion of the rail 2 where the drive wheels 4 and 5 are located. it can. As a result, it is possible to reliably prevent slippage of the drive wheels 4 and 5 and an unreasonable burden on the vehicle body 6 of the transport vehicle 1 according to the shape of the rail 2.

Next, a second embodiment will be described.
In the present embodiment, each drive wheel 4 or 5 is recognized by the current position recognizing means on the basis of the current position on the rail 2 and the travel route information which is a table of curvature at each position on the rail 2. Command values for the inverters 34 and 35 are calculated according to the difference in curvature of the rail 2 at the current position of the wheels 4 and 5, and the calculated command values are given to the inverters 34 and 35. These command values are calculated as command values that do not cause the drive wheels 4 and 5 to slip according to the difference in curvature of the rails 2.

  In other words, the travel route information is a table of curvatures of the portion of each position of the rail 2, and this travel route information is stored in the control unit 31 in advance. That is, the control unit 31 functions as a storage unit that stores the travel route information.

  Specifically, the travel route information in the portion of the rail 2 as shown in FIG. 5 is as shown in the table shown in FIG. That is, in the portion of the rail 2 as shown in FIG. 5, the curvature at each position of the inlet straight portion 2a and the outlet straight portion 2c is both 0, and each position of the curved portion 2b has a curvature C1.

Then, based on the current position recognized by the current position recognizing means by the control unit 31 and the travel route information that is the curvature of the rail 2 at the current position, the rails 2 and 5 where the driving wheels 4 and 5 are located. Command values for the inverters 34 and 35 are calculated according to the difference in curvature. That is, the control unit 31 functions as command value calculation means for calculating command values for the inverters 34 and 35 in accordance with the difference in curvature of the rail 2 at the current position of the drive wheels 4 and 5.
The command value calculated by the control unit 31 as the command value calculating means is given from the control unit 31 to the inverters 34 and 35.

Similarly to the first embodiment, the order will be described in accordance with FIG. 5. First, as shown in FIG. 5A, the transport vehicle 1 is positioned at the entrance straight portion 2 a, and the front and rear drive wheels 4, 5 are When both are located at the entrance straight portion 2a, the current position recognizing means recognizes that the drive wheels 4 and 5 are both located at the entrance straight portion 2a. As the travel route information, the curvature of the rail 2 at the current position of each drive wheel 4 and 5 is specified as 0.
That is, in this case, since the curvature of the rail 2 at the current position of each drive wheel 4 · 5 is the same, the control unit 31 gives the same command value to each inverter 34 · 35.

When the transport vehicle 1 travels and a part of the transport vehicle 1 reaches the curved portion 2b as shown in FIG. 5B, the front drive wheel 4 is positioned on the curved portion 2b, and the rear drive wheel 5 enters the entrance. It will be located in the straight line part 2a. In this case, it is recognized by the current position recognizing means that the front drive wheel 4 is located at the curved portion 2b and the rear drive wheel 5 is located at the inlet straight portion 2a. As the travel route information, the curvature of the rail 2 at the current position of the front drive wheel 4 is specified as C1, and the curvature of the rail 2 at the current position of the rear drive wheel 5 is specified as 0.
That is, in this case, since the curvature of the rail 2 at the current position of each drive wheel 4 · 5 is different, the control unit 31 as the command value calculation means is based on the current position of each drive wheel 4 · 5 and the travel route information. Thus, command values for the inverters 34 and 35 are calculated so as to correspond to the actual movement amounts of the drive wheels 4 and 5 according to the difference in curvature of the rail 2 at the current position of the drive wheels 4 and 5. The command value calculated here is such that the amount of movement of the front drive wheel 4 is greater than that of the rear drive wheel 5.
And the control part 31 gives this calculated command value to each inverter 34 * 35.

Next, when the transport vehicle 1 further proceeds and the transport vehicle 1 is positioned at the curved portion 2b as shown in FIG. 5C, both the front and rear drive wheels 4 and 5 are positioned at the curved portion 2b. The current position recognizing means recognizes that each of the drive wheels 4 and 5 is located on the curved portion 2b. As the travel route information, the curvatures of the drive wheels 4 and 5 are both specified as C1.
That is, in this case, since the curvature of the rail 2 at the current position of each drive wheel 4 · 5 is the same, the control unit 31 gives the same command value to each inverter 34 · 35.

Further, when the transport vehicle 1 further proceeds and a part of the transport vehicle 1 reaches the exit straight portion 2c as shown in FIG. 4D, the front drive wheel 4 is positioned at the exit straight portion 2c, and the rear It is recognized that the drive wheel 5 is located on the curved portion 2b. As the travel route information, the curvature of the rail 2 at the current position of the front drive wheel 4 is specified as 0, and the curvature of the rail 2 at the current position of the rear drive wheel 5 is specified as C1.
That is, in this case, since the curvature of the rail 2 at the current position of each drive wheel 4 and 5 is different again, as in the case where each drive wheel 4 and 5 is in the state shown in FIG. The control unit 31 as command value calculation means calculates command values for the inverters 34 and 35. The command value calculated here is such that the amount of movement of the front drive wheel 4 is smaller than that of the rear drive wheel 5.
And the control part 31 gives this calculated command value to each inverter 34 * 35.

When the transport vehicle 1 further advances and the transport vehicle 1 is positioned at the exit straight portion 2c as shown in FIG. 5E, both the front and rear drive wheels 4 and 5 are positioned at the exit straight portion 2c. The current position recognizing means recognizes that each of the drive wheels 4 and 5 is located at the exit straight portion 2c. Further, as the travel route information, the curvatures of the drive wheels 4 and 5 are both specified as 0.
That is, in this case, since the curvature of the rail 2 at the current position of each drive wheel 4 · 5 is the same, the control unit 31 gives the same command value to each inverter 34 · 35.

  As described above, the command values for the inverters 34 and 35 are calculated based on the current position of the drive wheels 4 and 5 on the rail 2 and the travel route information which is a table of curvature at each position of the rail 2 stored in advance. Then, by providing the calculated command value to each of the inverters 34 and 35, each drive wheel 4 is set with an optimum command value calculated according to the difference in curvature of the portion where the drive wheels 4 and 5 are located in the rail 2.・ 5 can be controlled. As a result, it is possible to reliably prevent slippage of the drive wheels 4 and 5 and an unreasonable burden on the vehicle body 6 of the transport vehicle 1 according to the shape of the rail 2.

Moreover, the conveyance vehicle which concerns on this invention is good also as following structures.
In the transport vehicle 1 shown in FIGS. 1 and 4, encoders 24 and 25 are provided in the motors 24 and 25 as current position recognition means. On the other hand, in the transport vehicle 101 of this configuration, as shown in FIGS. 8 and 9, as an encoder that constitutes the current position recognition means together with the control unit 131 (corresponding to the control unit 31 in the transport vehicle 1), One encoder 46 is used. In addition, about the part which overlaps with the conveyance vehicle 1, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
In this configuration, the encoder 46 is provided in contact with the rail 2, can grasp the speed and travel distance without using the rotational speed of the motors 24 and 25, and can determine the current position of the transport vehicle 1. It can be recognized. And since the attachment position of the encoder 46 and the position of each drive wheel 4 and 5 in the conveyance vehicle 1 are constant, if the position of the encoder 46 is known, the position of each drive wheel 4 and 5 with respect to that position can be calculated. .
More specifically, for example, if the difference in position between the drive wheels 4 and 5 and the encoder 46 is 2000 pulses and 5000 pulses, respectively, the position of the front drive wheel 4 is 20002000 pulses when the encoder 46 has 20000000 pulses. The position of the rear drive wheel 5 is 19995000 pulses.

  In this configuration, based on the detection signal from the encoder 46 input to the control unit 131, the difference between the position of the encoder 46 and the position of each drive wheel 4 and 5 is calculated to determine the number of pulses. The current position of each drive wheel 4 or 5 may be calculated from the relationship between the number of pulses and the diameter of each drive wheel 4 or 5. Then, a command value such as an optimum speed may be given to the inverters 34 and 35 according to the calculated current position.

  Further, as described above, since the positions of the drive wheels 4 and 5 with respect to the encoder 46 in the transport vehicle 1 are constant and can be determined in advance, the current position recognition means including the encoder 46 and the control unit 131 corresponds to the position of the encoder 46. Rather than calculating an appropriate command value by calculating the current position to be performed, command values to be given to the inverters 34 and 35 corresponding to the current position of the encoder 46 are created in advance as a table and stored in the control unit 131. You can leave it.

At this time, the command value table preferably has the following contents in order to reduce the speed change width of the rear drive wheel 5.
That is, while the transport vehicle 101 travels on the curved portion of the rail 2, the drive wheels 4 and 5 each have the highest speed at the central portion of the curved portion, and the drive wheels 4 and 5 enter the curved portion. Then, a command value table is set so that the speed is increased toward the center of the curved portion and the speed is decreased after passing the center. Thereby, the conveyance vehicle 1 can pass the curve part of the rail 2 in cooperation with the front drive wheel 4 and the rear drive wheel 5. FIG.
That is, since the suitable speed difference between the front drive wheel 4 and the rear drive wheel 5 when the transport vehicle 1 passes the curved portion of the rail 2 is determined, the speed of the front drive wheel 4 when passing the curved portion is determined. Is constant, and only the speed of the rear drive wheel 5 is changed, the speed change width of the rear drive wheel 5 with respect to the constant speed of the front drive wheel 4 increases. As described above, each drive wheel 4 By changing the respective speeds corresponding to the curved portions, the speed changes of the rear drive wheels 5 can be offset by the speed changes of the front drive wheels 4, and the speed change width of the rear drive wheels 5 is reduced. be able to.
In the table of command values of this content, the curved portion through which the transport vehicle 101 passes is provided in the middle of the straight portion in the rail 2, and the front and rear drive wheels 4 and 5 are not positioned on the curved portion. Can be adopted in case.

  The transport vehicle 1 in the present embodiment described above has a front drive wheel 4 and a rear drive wheel 5 disposed on one side of the vehicle body 6 as a plurality of travel drive wheels disposed at intervals in the vehicle body traveling direction. The drive wheels 4 and 5 are configured to travel while being guided by the same rail 2, but the invention is not limited to this. For example, the drive wheels 4 and 5 have drive wheels on the other side of the vehicle body. The present invention can also be applied to a configuration in which the driving wheels of the transport vehicle are guided by a plurality of rails, such as a configuration in which the driving wheels are guided by other rails.

The top view which shows the structure of the conveyance vehicle which concerns on this invention. Similarly rear view. Similarly side view. The block diagram which shows the control mechanism of the conveyance vehicle which concerns on this invention. The figure which shows the traveling process of the conveyance vehicle which concerns on this invention. The figure which shows the table of command value information. The figure which shows the table of driving route information. The top view which shows another structure of the conveyance vehicle which concerns on this invention. The block diagram which shows the control mechanism in another structure of the conveyance vehicle which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1.101 Conveyor vehicle 2 Rail 4 Front drive wheel 5 Rear drive wheel 6 Car body 24/25 Motor 31/131 Control part 34/35 Inverter 44/45 Encoder 46 Encoder

Claims (3)

A transport vehicle that includes a plurality of drive wheels disposed at intervals in the vehicle body traveling direction, and that is guided by a track having portions with different curvatures and travels along a predetermined travel route,
An individual driver for controlling each of the driving wheels;
When all of the driving wheels are located at the same curvature portion in the track, the same command value is given to the drivers, and when the driving wheels are located at different curvature portions in the track, And a control means for giving a command value corresponding to the curvature to each driver. Current position recognition means for recognizing the current position of each drive wheel; and storage means for command value information that is a table of the command values at each position of the trajectory,
The control means specifies a command value to be given to each driver based on a current position of each drive wheel recognized by the current position recognition means and the command value information. The listed transport vehicle. Current position recognition means for recognizing the current position of each drive wheel; storage means for storing travel route information that is a table of curvature at each position of the track; and curvature of the track at the current position of each drive wheel. Command value calculation means for calculating a command value for each driver according to a difference,
The command value calculation means calculates the command value based on the current position of each drive wheel recognized by the current position recognition means and the travel route information,
The transport vehicle according to claim 1, wherein the control unit gives the calculated command value to each driver.

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