JP5717149B2 - Automated guided vehicle - Google Patents

Description

  The present invention relates to an automatic guided vehicle used in a warehouse or a factory.

  In warehouses, factories, etc., for example, automatic guided vehicles are used to carry packages from one station to another. There are various types of automatic guided vehicles, and as an example, Patent Document 1 discloses an automatic guided vehicle 100 shown in FIG. The automated guided vehicle 100 can travel in the front-rear direction along the guide line 20 or can be laterally directed along the guide line 21 orthogonal to the guide line 20, as shown in FIG. The vehicle body 101 includes two drive units 102 and 103 that are turnable on the vehicle body 101, and a caster unit 104 that is turnably provided on the vehicle body 101.

  As shown in FIG. 9A, the drive units 102 and 103 include a wheel 105, a wheel driving motor 106 coaxially connected to the wheel 105, and a steering motor 107. When the steering motor 107 rotates, the entire drive units 102 and 103 turn around the turning axis R1 with respect to the vehicle body 101, whereby the traveling direction of the automatic guided vehicle 100 is switched from running to running or from running to running. On the other hand, when the wheel driving motor 106 rotates, the wheel 105 rotates around the axle R2, thereby causing the automatic guided vehicle 100 to travel or traverse.

  Further, as shown in FIG. 9B, the caster unit 104 includes a caster wheel 108 attached to the case 109 so as to be rotatable around the axle R4. The caster unit 104 is provided in the vehicle body 101 so as to freely turn around the turning axis R3.

JP 2002-264801 A

  The conventional automatic guided vehicle 100 mainly has the following two problems.

[Problem 1]
The offset D exists between the turning axis R3 and the axle R4 of the caster unit 104, and the caster wheel 108 draws an arc having a radius D around the turning axis R3 when the traveling direction is switched. Until the vehicle travels a certain distance, the posture of the vehicle body 101 is blurred. In addition, the direction of travel is switched from driving to horizontal, switching from horizontal to driving, switching from previous driving to rear driving, switching from rear driving to previous driving, switching from right horizontal to left horizontal, And switching from the left row to the right row.

[Problem 2]
When the traveling direction is switched from traveling to transverse, and when the traveling direction is switched from traveling to traveling, the steering motor 107 is rotated in a stopped state to change the direction of the wheel 105 by 90 ° (stationary), so that the wheel 105 and the road surface And the wheel 105 and / or the road surface are worn. When wear occurs, maintenance takes time and money. In addition, the wear powder generated by the wear is a cause of reducing the cleanliness of the warehouse or factory.

  This invention is made | formed in view of the said situation, The place made into the subject provides the automatic guided vehicle which can reduce the abrasion of the wheel and road surface which arise when the advancing direction switches, and the blurring of an attitude | position. There is.

In order to solve the above problems, an automatic guided vehicle according to the present invention is an automatic guided vehicle including a vehicle body and a plurality of drive units attached to the vehicle body so as to be capable of turning around a turning axis. A battery and a control unit for controlling the plurality of drive units, wherein the drive units each include a first unit including a first wheel and a first geared motor for driving the first wheel, a second wheel, and the second wheel. A second unit including a motor with a second gear for driving two wheels, the rotation axis of the first wheel and the rotation axis of the second wheel are on the same straight line, and the control unit is in traveling or traversing , First and second constituting other drive units while controlling the power running of the first and second geared motors constituting a part of the plurality of drive units. The regenerative control can be performed on the motor with the motor, and the electric power obtained by the regenerative control can be regenerated in the battery. Further, the control unit can perform the regenerative control based on whether or not the traveling conveyance path is a slope, or on the basis of the load. It is characterized by determining whether to perform .

  According to this configuration, the first geared motor constituting the first unit and the second geared motor constituting the second unit are rotated in the reverse direction, and the first and second wheels are rotated in the reverse direction. The drive unit can be turned with respect to the vehicle body. In other words, according to this configuration, when the traveling direction is switched, the first and second wheels can be changed in direction while rotating the first and second wheels, so that the first and second wheels and the road surface can be changed. The occurrence of wear can be reduced.

Further, according to this configuration, a steering motor (see reference numeral 107 in FIG. 9A) is not required, so that the drive unit can be reduced in size (particularly, reduced in height) as compared with the prior art. The downsizing of the drive unit has various advantageous effects as described below.
(1) The degree of freedom of arrangement of the drive unit in the vehicle body can be increased.
(2) The vehicle body itself can be miniaturized (low profile).
(3) When the vehicle body dimensions are not changed, a larger capacity battery can be mounted.

  The automatic guided vehicle preferably has three or more drive units and is configured to be grounded only by the drive units.

  According to the above-described configuration in which only three or more drive units are grounded, that is, the above-described configuration in which the caster unit (see FIG. 9B) is not grounded, posture blur due to the offset of the caster unit is reduced. can do.

  In the automatic guided vehicle, it is preferable that the circle drawn by the first and second wheels when the drive unit turns around the turning axis and the circle drawn by the first and second geared motors are substantially equal.

  According to this configuration, the first and second wheels can be moved away from the turning shaft as much as possible while avoiding an increase in the size of the drive unit when viewed in plan, so that the first time when the drive unit turns with respect to the vehicle body. In addition, the second wheel can be rotated without difficulty, and the wear reduction effect can be further enhanced.

  ADVANTAGE OF THE INVENTION According to this invention, the automatic guided vehicle which can reduce the abrasion of the wheel and road surface which arise when the advancing direction switches, and the blurring of a posture can be provided.

It is a plane schematic diagram of the automatic guided vehicle which concerns on the Example of this invention. It is the (A) top view and (B) side view of the drive unit with which the automatic guided vehicle concerning an example was equipped. It is a control block diagram of the automatic guided vehicle concerning an example. It is a figure for demonstrating the motion of the automatic guided vehicle which concerns on an Example at the time of advancing direction switching from driving | running | working to a traverse. It is a figure for demonstrating the motion of the automatic guided vehicle which concerns on an Example at the time of advancing direction switching from a front run to a back run. It is a plane schematic diagram of the automatic guided vehicle which concerns on the 1st modification of this invention. It is a plane schematic diagram of the automatic guided vehicle which concerns on the 2nd modification of this invention. It is a plane schematic diagram of the conventional automatic guided vehicle. It is a side view of (A) drive unit with which the conventional automatic guided vehicle was equipped, and (B) caster unit.

  Hereinafter, embodiments and modifications of the automatic guided vehicle according to the present invention will be described with reference to the accompanying drawings.

[Example]
FIG. 1 shows an automatic guided vehicle 1A according to an embodiment of the present invention. The automated guided vehicle 1A travels in the front-rear direction along a guide line 20 laid along a predetermined transport path such as a warehouse or a factory, or in the left-right direction along a guide line 21 orthogonal to the guide line 20 You can turn sideways. As shown in the figure, the automatic guided vehicle 1A includes a vehicle body 2 and three drive units (first to third drive units 3, 4,. 5), and a control unit 10 and a battery 11 (not shown). In the present embodiment, the configurations of the first to third drive units 3, 4, and 5 are the same.

  As shown in FIG. 2, the first to third drive units 3, 4, and 5 include a first unit including a first wheel 6a and a first geared motor 7a for driving the first wheel 6a, and a second wheel 6b. And a second unit including a second geared motor 7b for driving the second wheel 6b.

  The first geared motor 7a includes a brushless motor unit 8a that rotates about the rotation axis Ra1 under the control of the control unit 10, and a rotation of the brushless motor unit 8a about the rotation axis Ra1 that translates the rotation axis Ra1 in the horizontal direction. And a gear portion 9a that converts the rotation about the rotation axis Ra2. The gear portion 9a may be a transmission gear that reduces the rotational speed at a predetermined ratio.

  The first wheel 6a is provided on the rotation axis Ra2 of the gear portion 9a. When the brushless motor unit 8a rotates around the rotation axis Ra1, the first wheel 6a rotates around the rotation axis Ra2. The rotation direction of the first wheel 6a is the same as the rotation direction of the brushless motor unit 8a. When the rotation direction of the brushless motor unit 8a is changed by the control unit 10, the rotation direction of the first wheel 6a also changes.

  The second geared motor 7b has the same configuration as the first geared motor 7a. More specifically, the second geared motor 7b has a brushless motor portion 8b that rotates about the rotation axis Rb1 under the control of the control unit 10, and a rotation about the rotation axis Rb1 of the brushless motor portion 8b. And a gear portion 9b that converts the rotation about the rotation axis Rb2 that is translated in the direction. The gear portion 9b may be a transmission gear that reduces the rotational speed at a predetermined ratio.

  The second wheel 6b also has the same configuration as the first wheel 6a. More specifically, the second wheel 6b is provided on the rotation axis Rb2 of the gear portion 9b. When the brushless motor unit 8b rotates around the rotation axis Rb1, the second wheel 6b rotates around the rotation axis Rb2. The rotation direction of the second wheel 6b is the same as the rotation direction of the brushless motor unit 8b. When the rotation direction of the brushless motor unit 8b is changed by the control unit 10, the rotation direction of the second wheel 6b also changes.

  As shown in FIG. 2A, the first and second geared motors 7a and 7b are substantially L-shaped when viewed in plan, and are combined so as to face each other. By arranging the first and second geared motors 7a, 7b in this way, the first unit (6a, 7a) and the second unit (6b, 7b) have a point-symmetric relationship with respect to the turning axis R. The rotation axis Ra2 of the first wheel 6a and the rotation axis Rb2 of the second wheel 6b are arranged on the same straight line.

  Further, as shown in FIG. 2A, in this embodiment, when the first to third drive units 3, 4, and 5 turn around the turning axis R, the turning axes of the first and second wheels 6a and 6b. The first and second circles C drawn by the portion farthest from R and the circle C ′ drawn by the portions farthest from the turning axis R of the first and second geared motors 7a and 7b are substantially equal. A distance D between the second wheels 6a and 6b and the turning axis R is determined. In other words, in this embodiment, the distance D is made as large as possible within a range where the circle C does not become larger than the circle C ′. Thus, when the first to third drive units 3, 4, 5 are turned around the turning axis R, the first and second wheels 6 a, 6 b can be rotated without difficulty. On the other hand, when the circle C ′ increases, the degree of freedom of arrangement of the first to third drive units 3, 4, and 5 in the vehicle body 2 decreases. For these reasons, when designing the first to third drive units 3, 4, 5, first, the arrangement and shape of the first and second geared motors 7 a, 7 b are determined so that the circle C ′ becomes as small as possible. After that, it is preferable to determine the arrangement of the first and second wheels 6a and 6b so that the distance D is as large as possible within a range where the circle C does not become larger than the circle C ′.

  When the first and second wheels 6a and 6b rotate in the same direction, the first to third drive units 3, 4, and 5 generate driving force that causes the automatic guided vehicle 1A to travel or traverse. On the other hand, when the first and second wheels 6a and 6b rotate in the opposite directions, the first to third drive units 3, 4, and 5 turn about the turning axis R by an angle corresponding to the amount of the rotation. At this time, the automatic guided vehicle 1A does not travel or traverse and remains stationary.

  FIG. 3 shows a control block diagram of the automatic guided vehicle 1A. Based on sensor information from various sensors provided on the vehicle body 2, the control unit 10 individually controls the power running of the first and second geared motors 7 a, 7 b of the first to third drive units 3, 4, 5. Regenerative control. The power of the battery 11 is supplied to the first and second geared motors 7a and 7b that are subjected to power running control. On the other hand, the electric power obtained in the regeneratively controlled first and second geared motors 7a and 7b is regenerated by the battery 11 or the other first and second geared motors 7a and 7b that are power-run controlled. Used as part of the power required.

There are various modes of control of the first to third drive units 3, 4, and 5 by the control unit 10. Some of them are exemplified below.
(I) When traveling on an uphill road The first and second geared motors 7a and 7b of all the drive units 3, 4, and 5 are controlled to be powered and rotated in the same direction.
(Ii) When traveling on a downhill road The first drive of the second drive unit 4 while rotating the first and second geared motors 7a, 7b of the first and third drive units 3, 5 in the same direction by controlling the power running The second gear-equipped motors 7a and 7b are regeneratively controlled to cause the battery 11 to regenerate power.
(Iii) When the traveling direction is switched from running to traversing: The first and second geared motors 7a, 7b of all the drive units 3, 4, 5 are rotated in the opposite direction by controlling the power running, and all the drive units 3, 4, 5 Is turned 90 ° with respect to the vehicle body 2.

  In the present embodiment, the sensor information includes a result of detecting whether the transport path during travel (crossing) is a flat road, an uphill road, or a downhill road, and a result of detecting the load of the load being transported. It is. The control unit 10 determines whether or not to regeneratively control some of the first to third drive units 3, 4, and 5 based on the sensor information. For example, the control unit 10 performs regenerative control of some drive units when the conveyance path is a downhill road and when the load is small. This is because in these cases, the driving force required to run (traverse) the automatic guided vehicle 1A may be small.

  Next, a series of movements of the automatic guided vehicle 1A when the traveling direction is switched from running to traversing will be described with reference to FIG.

  FIG. 4A shows an automatic guided vehicle 1 </ b> A traveling along the guide line 20. At this time, the control unit 10 rotates the first and second geared motors 7a, 7b of all the drive units 3, 4, 5 in the same direction. As a result, the first and second wheels 6a and 6b of all the drive units 3, 4, and 5 rotate in the same direction in which the automatic guided vehicle 1A can travel.

  FIG. 4B shows the automatic guided vehicle 1 </ b> A stopped at the intersection of the guide line 20 and the guide line 21. At this time, the first and second geared motors 7a, 7b of all the drive units 3, 4, 5 are completely stopped without rotating.

  FIG. 4C shows the automatic guided vehicle 1A after all the drive units 3, 4, and 5 have turned 90 ° from the state shown in FIG. When all the drive units 3, 4, 5 are turned, the control unit 10 rotates the first and second geared motors 7 a, 7 b of all the drive units 3, 4, 5 in the reverse direction, This is done by rotating the first and second wheels 6a and 6b in the opposite directions.

  FIG. 4D shows an automatic guided vehicle 1 </ b> A that is traversing along the guide line 21. As in FIG. 5A, at this time, the control unit 10 rotates the first and second geared motors 7a and 7b of all the drive units 3, 4, and 5 in the same direction, and all the drive units 3, 4, 5 are rotated. The first and second wheels 6a and 6b are rotated in the same direction. However, since all the drive units 3, 4, and 5 are turned 90 ° between FIGS. The direction is 90 ° different from FIG.

  Next, a series of movements of the automatic guided vehicle 1A when the traveling direction is switched from the front traveling to the rear traveling will be described with reference to FIG.

  FIG. 5A shows an automatic guided vehicle 1 </ b> A that is traveling forward along the guide line 20. At this time, the control unit 10 rotates the first and second geared motors 7a, 7b of all the drive units 3, 4, 5 in the same direction. Accordingly, the first and second wheels 6a and 6b of all the drive units 3, 4, and 5 rotate in the same direction in which the automatic guided vehicle 1A can run forward.

  FIG. 5B shows the automatic guided vehicle 1 </ b> A stopped on the guide line 20. At this time, the first and second geared motors 7a, 7b of all the drive units 3, 4, 5 are completely stopped without rotating.

  FIG. 5C shows the automatic guided vehicle 1 </ b> A traveling backward along the guide line 20. At this time, the control unit 10 rotates the first and second geared motors 7a, 7b of all the drive units 3, 4, 5 in the direction opposite to that shown in FIG. Accordingly, the first and second wheels 6a and 6b of all the drive units 3, 4, and 5 rotate in the same direction in which the automatic guided vehicle 1A can travel backward.

  As mentioned above, although the Example of the automatic guided vehicle concerning this invention was described, the structure of this invention is not limited to the said Example, The various modifications which are illustrated below can be considered.

[First Modification]
FIG. 6 shows an automatic guided vehicle 1B according to a first modification of the present invention. As shown in the figure, the automatic guided vehicle 1B is different from the automatic guided vehicle 1A in that a caster unit 12 is provided instead of the third drive unit 5. The caster unit 12 has the same configuration as the caster unit 104 (see FIG. 9B) in the conventional automatic guided vehicle 101.

  Since the automatic guided vehicle 1B according to this modification includes the caster unit 12, it cannot reduce the shake of the posture when the traveling direction is switched, but can reduce the wear. When only wear is regarded as a problem, the production cost can be reduced by using a configuration in which the caster unit 12 is used in combination as in the present modification.

[Second Modification]
FIG. 7 shows an automatic guided vehicle 1C according to a second modification of the present invention. As shown in the drawing, the automatic guided vehicle 1C is different from the automatic guided vehicle 1A in that it includes four drive units 3, 4, 13, and 14. Similar to the first and second drive units 3 and 4, the fourth and fifth drive units 13 and 14 are attached to the vehicle body 2 so as to be capable of turning around the turning axis R. The configurations of the fourth and fifth drive units 13 and 14 are the same as the configurations of the first and second drive units 3 and 4.

  According to the automatic guided vehicle 1C according to this modification, it is possible to generate a larger driving force during traveling and traversing than the automatic guided vehicle 1A.

[Other variations]
The number of drive units is not limited to three (examples), two (first modification), and four (second modification), and may be any number of two or more. However, when it is two, it is necessary to use the caster unit 12 together like the automatic guided vehicle 1B according to the first modification.

  The drive units 3, 4, 5, 13, 14 and the caster unit 12 are preferably attached to the vehicle body 2 via an alignment mechanism. By using the alignment mechanism, the axial load can be evenly distributed and the ground contact can be improved.

  The sensor information used for determining whether or not to perform regenerative control in the control unit 10 is not limited to that exemplified in the embodiment. The control unit 10 may make the determination based on whether or not a predetermined condition other than the sensor information is satisfied. For example, the control unit 10 may perform regenerative control of some drive units when traveling or traversing a predetermined portion of the conveyance path.

1A, 1B, 1C Automatic guided vehicle 2 Car body 3 First drive unit 4 Second drive unit 5 Third drive unit 6a First wheel 6b Second wheel 7a First geared motor 7b Second geared motor 8a, 8b Brushless motor unit 9a, 9b Gear unit 10 Control unit 11 Battery 12 Caster unit 13 Fourth drive unit 14 Fifth drive unit 20 Guide line 21 Guide line

Claims (3)

An automatic guided vehicle comprising a vehicle body and a plurality of drive units attached to the vehicle body so as to be capable of turning about a turning axis;
Battery,
A control unit for controlling the plurality of drive units;
With
The drive units are respectively
A first unit including a first wheel and a first geared motor for driving the first wheel;
A second unit including a second wheel and a second geared motor for driving the second wheel;
With
The rotation axis of the first wheel and the rotation axis of the second wheel are on the same straight line;
The control unit is configured to perform the power running control of the first and second geared motors constituting the drive units of some of the plurality of drive units during running or traversing, and the first and second drive units constituting the other drive units. Regenerative control of a motor with two gears, the battery can regenerate the electric power obtained by the regenerative control,
Furthermore, the control unit determines whether or not the traveling conveyance path is a slope, or whether or not to perform the regenerative control based on a load . 2. The automatic guided vehicle according to claim 1, wherein the number of the drive units is three or more and is grounded only by the drive units. A circle drawn by the first and second wheels when the drive unit turns about the turning axis is substantially equal to a circle drawn by the first and second geared motors.
The automatic guided vehicle according to claim 1 or 2 .

Images