Unmanned carrier, and driving method therefor

Abstract

To propose a novel configuration for an unmanned carrier provided with an elevating / lowering stand.SOLUTION: An unmanned carrier for carrying an article comprises: placing means comprising an elevating / lowering stand capable of placing and vertically elevating / lowering the article; elevating / lowering means for elevating / lowering the elevating / lowering stand; traveling means comprising traveling tires grounding on a floor face, which is connected with a motor; and separation means for separating the traveling tires from the floor face. The traveling means comprises a first gear. The elevating / lowering means comprises a second gear. It is so constituted that the first gear and the second gear are engaged with each other when the traveling tires are separated from the floor face by the separation means. The elevating / lowering stand is elevated / lowered by driving the second gear by the motor.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an automated guided vehicle that travels on a floor surface in a factory or the like to transport articles, and a driving method thereof. [Background technology]

[0002] 2. Description of the Related Art Conventionally, as disclosed in Patent Document 1, for example, there has been known an automatic guided vehicle (AGV) that travels on the floor surface in a factory or the like to transport articles.

[0003] This type of automated guided vehicle has a vehicle body frame, a motor fixed to the vehicle body frame, wheels rotatably supported on the vehicle body frame and driven by the motor, a lifting platform that can be raised and lowered relative to the vehicle body frame, and an actuator fixed to the vehicle body frame for raising the lifting platform. The actuator is composed of an air cylinder, a motor, etc.

[0004] An automated guided vehicle configured in this manner can enter under a shelf that stores manufacturing parts and the like, and then lift up the shelf by raising the lifting platform, thereby transporting the shelf. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-184113 A Summary of the Invention [Problem to be solved by the invention]

[0006] Since the transportation efficiency can be improved by being able to transport more manufacturing parts at once, there is a demand for automatic guided vehicles to have a higher maximum load capacity.In addition, there is a demand for shelves to be able to set the lowest shelf lower in order to expand storage space and ensure more shelves.

[0007] However, in order to increase the maximum load capacity, it is necessary to increase the size of the air cylinder and motor that constitute the lifting actuator. For example, in an automated guided vehicle equipped with a linear air cylinder arranged vertically, the size of the air cylinder must be increased to increase the thrust, which increases the vertical dimension of the automated guided vehicle. Also, in the case where the lifting actuator is composed of a motor, increasing the size of the motor will increase the vertical dimension of the automated guided vehicle.

[0008] In this way, if the vertical dimension of an automated guided vehicle increases, it becomes difficult to keep the height of the lifting platform low, and it becomes impossible to fit between the lowest shelf and the floor, limiting the types of shelves that can be used and reducing versatility.

[0009] In view of the above problems, the present invention proposes a novel configuration for an automated guided vehicle having a lift platform. [Means for solving the problem]

[0010] The problem to be solved by the present invention has been described above, and the means for solving this problem will now be described.

[0011] According to one aspect of the present invention, an unmanned guided vehicle for transporting goods comprises: placement means having a lifting platform on which goods can be placed and which can be raised and lowered up and down; lifting means for raising and lowering the lifting platform; running means having drive tires connected to a motor and which contact a floor surface; and separation means for separating the running tires from the floor surface, wherein the running means has a first gear and the lifting means has a second gear, and the first gear and the second gear are configured to mesh when the running tires are separated from the floor surface by the separation means, and the lifting platform is raised and lowered by driving the second gear by the motor.

[0012] According to one aspect of the present invention, the loading means has an inclined portion provided on the underside of the lifting platform, and the lifting means has a moving support part that supports the inclined portion from below and moves horizontally by driving the second gear, and the moving support part moves horizontally to push the inclined portion upward and lift up the lifting platform.

[0013] Furthermore, according to one aspect of the present invention, the inclined portions are arranged in a pair in the horizontal direction, the moving support portions are arranged in a pair in the horizontal direction, and by driving the second gear, both moving support portions are each moved in the horizontal direction, and both inclined portions are each pushed upward.

[0014] According to one aspect of the present invention, the lifting means has a first rack which meshes with the second gear from above and extends horizontally, and a second rack which meshes with the second gear from below and extends horizontally, each rack being provided with the moving support part, and each rack moves horizontally in opposite directions when the second gear is driven, and each moving support part provided on each rack moves horizontally to raise and lower the lifting platform.

[0015] According to one aspect of the present invention, the inclination angle of the inclined portion is set so that the distance of horizontal movement of the moving support portion is greater than the distance the inclined portion is raised when the moving support portion moves horizontally.

[0016] Moreover, according to one aspect of the present invention, there is provided a method for driving an unmanned guided vehicle for transporting goods, the unmanned guided vehicle comprising: placement means for placing an article on the unmanned guided vehicle and capable of raising and lowering the article up and down; lifting means for raising and lowering the lifting platform; running means connected to a motor and having running tires that contact a floor surface; and separating means for separating the running tires from the floor surface, the running means having a first gear and the lifting means having a second gear, the first gear and the second gear being configured to mesh when the running tires are separated from the floor surface by the separating means, and the method for driving the unmanned guided vehicle comprises raising and lowering the placement means by driving the second gear with the motor. Effect of the Invention

[0017] The present invention provides the following advantages. That is, according to one aspect of the present invention, the motor for traveling can be used as the actuator for lifting and lowering, so that an automated guided vehicle can be configured with a small number of motors. This allows the automated guided vehicle to be made more compact, and in turn, the floor of the lifting platform can be made lower. Furthermore, since a dedicated actuator for lifting and lowering is not required, the maximum load capacity can be increased without increasing the size of the dedicated actuator, and thus, a lower floor due to the compactness of the automated guided vehicle and an increased maximum load capacity can be simultaneously achieved. [Brief description of the drawings]

[0018] [Figure 1] 1 is a perspective view of an automatic guided vehicle according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a front view of an automatic guided vehicle according to an embodiment of the present invention. [Diagram 3] FIG. 13 is a diagram for explaining the arrangement of a third gear, a rack, etc. [Figure 4] FIG. 13 is a diagram showing a state in which the first gear and the second gear are meshed with each other. [Diagram 5] (A) is a diagram showing the state in which the lifting platform is lowered during movement, (B) is a diagram showing the state in which the lifting platform is raised during lift-up, and (C) is a diagram showing the state when moving with the lifting platform raised. [Figure 6] (A) is a diagram showing the state in which the lifting platform is lowered during movement, (B) is a diagram showing the state in which the lifting platform is raised during lift-up, and (C) is a diagram showing the state when moving with the lifting platform raised. [Figure 7] 5A to 5C are diagrams for explaining the configuration of an inclined portion, etc.; [Figure 8] FIG. 13 is a diagram for explaining how an automated guided vehicle enters under a shelf. [Figure 9] FIG. 13 is a diagram illustrating the state in which the shelf is lifted up. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] An automated guided vehicle according to an embodiment of the present invention will now be described with reference to the drawings, in which Fig. 1 is a perspective view of an automated guided vehicle according to an embodiment of the present invention, and Fig. 2 is a front view of the same.

[0020] 1 and 2, the automated guided vehicle 1 is equipped with a placement means 2 having a lifting platform 21 on which an article is placed and which can be raised and lowered. The lifting platform 21 is configured in a plate shape, and its upper surface functions as a placement surface 22 for the article. The placement surface 22 is configured to have a substantially rectangular shape having horizontal and vertical dimensions in X-axis and Y-axis directions that are perpendicular to each other in a horizontal plane, and rises and falls in the Z-axis direction that is perpendicular to the X-axis and Y-axis directions.

[0021] 1, wedge-shaped inclined portions 24, 25 are provided on the underside of the lifting stand 21. The inclined portions 24, 25 are formed, for example, by fixing a wedge-shaped plate material formed as a separate member from the lifting stand 21 to the underside of the lifting stand 21.

[0022] As shown in Fig. 2, the inclined portions 24, 25 are provided at four locations, each configured to be long so as to extend in the X-axis direction, and configured to form a pair in the X-axis direction and a pair in the Y-axis direction. Fig. 2 shows a state in which a pair of left and right inclined portions 24, 25 are provided in a row on the lower side in the Y-axis direction, and a pair of left and right inclined portions 24, 25 are provided in a row on the upper side in the Y-axis direction.

[0023] As shown in Figures 1 and 2, the lifting platform 21 is configured to be able to rise and fall relative to the vehicle body frame 7, which is configured to be approximately H-shaped when viewed from above, and is configured to rise and fall in the vertical direction without rotating within a horizontal plane by linear bushings 5, 5 provided at multiple locations.

[0024] As shown in Figures 3 and 4, the vehicle body frame 7 is provided with a traveling means 6 and an isolation means 8. The traveling means 6 has a motor 60, a gearbox 62 to which the motor 60 is connected, traveling tires 64 fixed to an output shaft 62s of the gearbox 62, and a first gear 61 fixed to the output shaft 62s. The motor 60 is fixed to a side surface of the gearbox 62, and the output shaft of the motor 60 is connected to the input shaft of the gearbox 62. The motor 60 is driven by a battery mounted on the vehicle body frame 7, and the drive of the motor 60 is controlled by a control device (not shown).

[0025] The isolation means 8 has an isolation motor 82 that drives a gear 82a that engages with a bracket 62a provided on one end of the gear box 62. The isolation motor 82 is supported by the body frame 7. Note that the isolation means 8 may be any actuator for rotating the gear box 62, and is not particularly limited to a motor.

[0026] The arm portion 62b provided on the gearbox 62 on the opposite side of the bracket 62a across the motor 60 is rotatably connected to and supported by the rotation shaft 13 fixed to the vehicle body frame 7. When the bracket 62a is moved upward by the isolation motor 82, the arm portion 62b rotates about the rotation shaft 13, and the output shaft 62s of the gearbox 62 moves upward. Accordingly, the traveling tire 64 also moves upward and is lifted off the floor surface 3 (FIG. 4).

[0027] A floor-side stopper 11 that protrudes toward the floor surface 3 is provided at the other end of the arm portion 62b opposite to the gear box 62. As shown in Fig. 5(B), when the traveling tire 64 moves upward and separates from the floor surface, the floor-side stopper 11 touches the floor surface 3, and the movement of the automated guided vehicle 1 is restricted by the frictional force between the floor-side stopper 11 and the floor surface 3. On the other hand, as shown in Figs. 5(A) and (C), when the traveling tire 64 touches the floor surface 3, the floor-side stopper 11 leaves the floor surface 3, and the restriction of the movement of the automated guided vehicle 1 by the floor-side stopper 11 is released, and the automated guided vehicle 1 becomes able to move.

[0028] 4, the arm portion 62b is provided with a rack stopper 12 along the upper side of the arm portion 62b. A contact portion 12a at the tip of the rack stopper 12 abuts against a side surface of the rack 47, which will be described in detail later, thereby restricting the horizontal movement of the rack 47 and restricting the elevation and lowering of the lifting platform 21.

[0029] Specifically, as shown in FIG. 5(C), when the unmanned guided vehicle 1 is in a lifted-up state with the running tires 64 in contact with the floor surface 3 and capable of moving, the rack stopper 12 comes into contact with the rack 47 to restrict the horizontal movement of the rack 47, thereby maintaining the height position of the lifting platform 21.

[0030] On the other hand, as shown in Fig. 5(B), when the traveling tires 64 move upward and separate from the floor surface, the rack stopper 12 does not contact the rack 47, allowing the rack 47 to move and the lifting platform 21 to rise and fall. Note that Fig. 4 shows a state in which the rack stopper 12 does not function and the lifting platform 21 is allowed to rise and fall.

[0031] As shown in FIG. 2, in the vehicle body frame 7, the traveling means 6 and the isolation means 8 are arranged adjacent to each other in the X-axis direction to form a set of units, and this set of units is also arranged as a pair in the Y-axis direction, for a total of two sets of units.

[0032] As shown in FIG. 2 and FIG. 5(A), driven tires 17 are provided at four positions on the lower part of the body frame 7, and the body frame 7 is supported by the driven tires 17 so as to be movably relative to the floor surface 3.

[0033] 3, the lifting means 4 has moving support parts 46a, 47a that support the inclined parts 24, 25 provided on the lower surface of the lifting platform 21 from below and move horizontally by driving the second gear 42, a pair of racks 46, 47, and a third gear 43. The moving support parts 46a, 47a move horizontally to push up the inclined parts 24, 25, thereby lifting up the lifting platform 21.

[0034] 3 and 4, a shaft 41 is fixed to the body frame 7 with its axial direction set as the Y-axis direction, and a second gear 42 and a third gear 43 are fixed to the shaft 41. The second gear 42 meshes with a first gear 61 fixed to an output shaft 62s of a gear box 62 when the lifting platform 21 is lifted or lowered.

[0035] The third gear 43 is configured to mesh with teeth of a pair of racks 46, 47 that move in the X-axis direction, and functions as a pinion gear. The pair of racks 46, 47 are supported by linear guides 45a, 45b, respectively, which extend in the X-axis direction relative to the body frame 7, and extend horizontally so as to sandwich the third gear 43 from above and below. When the third gear 43 rotates, the racks 46, 47 move horizontally in opposite directions to each other.

[0036] The rack that meshes with the third gear 43 from above is referred to as a first rack 46, and the rack that meshes with the third gear 43 from below is referred to as a second rack 47. The ends of the racks 46, 47 are provided with moving support parts 46a, 47a that support the inclined parts 24, 25 from below, respectively.

[0037] 7, the moving support part 46a has an axis part 46b extending in the Y-axis direction (FIG. 1) and a roller 46c rotatably provided on the axis part, and the roller 46c comes into contact with the inclined surface 24a of the inclined part 24 to support the inclined part 24 from below. The other moving support part 47a and the inclined part 25 (see FIGS. 5(A) and (B)) are similar, and the description thereof will be omitted.

[0038] The inclined portion 24 is composed of a lower horizontal portion 24b that is supported by rollers 46c when the lifting platform 21 is lifted up to the highest position, an upper horizontal portion 24c that is supported by rollers 46c when the lifting platform 21 is raised to the highest position, and a slope 24a that connects the lower horizontal portion 24b and the upper horizontal portion 24c.

[0039] The angle of the slope 24a of the inclined portion 24 is, for example, about 11.3 degrees, in other words, a gradient of 1 / 5, and is set so that the vertical distance is 10 cm for a horizontal distance of 50 cm. In this case, when the roller 46c moves horizontally to push up the inclined portion 24, the vertical component force F1 acting on the roller 46c can be made about 1 / 5 compared to when the roller 46c moves vertically, which means that it is possible to lift up with a small force.

[0040] In the above lift-up, the so-called wedge effect can be utilized. That is, the inclined portion 24 can be pushed up with a small thrust, and the load on the motor 60 (FIG. 4) that serves as the drive source for the rollers 46c can be reduced. This makes it possible to employ a relatively small motor with low output. Alternatively, the present invention can be implemented without enlarging the size of the motor that serves as the drive source for traveling.

[0041] As described above, according to the present invention, the motor for traveling can be used as the actuator for lifting and lowering, so that an automated guided vehicle can be configured with a small number of motors. This allows the automated guided vehicle to be made more compact, and in turn allows the lifting platform to have a lower floor. Furthermore, since a dedicated actuator for lifting and lowering is not required, the maximum load capacity can be increased without increasing the size of the dedicated actuator, and thus, a lower floor due to the compactness of the automated guided vehicle and an increased maximum load capacity can be simultaneously achieved.

[0042] Next, an example of transportation using the automatic guided vehicle having the above configuration will be described. As shown in FIG. 8, shelf 90 is configured by attaching multiple shelves 92 to a pillar 91, and it is envisioned that various items, such as equipment parts, assemblies of equipment parts, tools, etc., will be placed on each shelf 92.

[0043] An underfloor space 9 with a height H9 is provided between the lowest shelf board 92 and the floor surface 3, and the automated guided vehicle 1 with a height H1 enters this underfloor space 9 through the gap between the pillars 91. At this time, the running tires 64 and driven tires 17 of the automated guided vehicle 1 are placed on the floor surface 3, and the automated guided vehicle 1 moves by driving the running tires 64 with a motor. The automated guided vehicle 1 is equipped with a control device and a communication device (not shown), and moves automatically by remote control or the like.

[0044] Furthermore, when moving without a load, the running tires 64 are in contact with the floor surface 3 as shown in FIG. 5(A), and the first gear 61 does not mesh with the second gear 42 as shown in FIG. 6(A), and the third gear 43 is not driven.

[0045] When moving without a load, the traveling tires 64 are in contact with the floor surface 3 as shown in Fig. 5(A), and the racks 46, 47 (Fig. 5(A)) are positioned so that the moving support parts 46a, 47a are in positions close to the third gear 43 as shown in Fig. 6(A). As a result, the moving support parts 46a, 47a support the upper horizontal parts 24c, 25c of the inclined parts 24, 25, and the lifting platform 21 is lowered to the lowest position.

[0046] Then, as shown in FIG. 9, when the unmanned transport vehicle 1 enters the underfloor space 9 of the shelf 90, the lifting platform 21 is lifted up to a height H2, pushing up the lowest shelf board 92, thereby lifting the pillar 91 of the shelf 90 off the floor surface 3 and making it ready for transport.

[0047] At this time, as shown in Fig. 5(B), first, the isolation motor 82 is driven to isolate the traveling tires 64 from the floor surface 3, and as shown in Fig. 6(B), the first gear 61 is meshed with the second gear 42. Then, the motor 60 is driven to rotate the first gear 61 counterclockwise to drive the second gear 42 and the third gear 43, and the racks 46, 47 (Fig. 5(B)) are moved in opposite directions to each other, thereby moving the movable support parts 46a, 47a in a direction away from the third gear 43. The movement of the movable support parts 46a, 47a pushes up the inclined parts 24, 25, and the lifting platform 21 is lifted up.

[0048] 5(C) and 6(C), when the isolation motor 82 is driven to bring the traveling tires 64 into contact with the floor surface 3 from the lifted-up state, the rack stopper 12 comes into contact with the rack 46, restricting the horizontal movement of the rack 46, and also restricts the horizontal movement of the other rack 47 via the third gear 43. This also restricts the horizontal movement of the moving support parts 46a, 47a, and the lifted-up state of the lifting platform 21 is maintained.

[0049] In this state, the traveling tires 64 are driven to move the unmanned transport vehicle 1 and the shelf 90 is moved to the desired location. Then, as shown in FIG. 5(B), the isolation motor 82 is first driven to isolate the traveling tires 64 from the floor surface 3, thereby releasing the restriction on the movement of the rack 47 by the rack stopper 12, and the first gear 61 is meshed with the second gear 42, as shown in FIG. 6(B).

[0050] Then, as shown in FIG. 6(B), the motor 60 is driven to rotate the first gear 61 in a clockwise direction, thereby driving the second gear 42 and the third gear 43, and the racks 46, 47 (FIG. 5(B)) are moved in the opposite directions to each other, so that the moving support parts 46a, 47a are moved in a direction approaching the third gear 43. As a result, as shown in FIG. 6(A), the moving support parts 46a, 47a move to the positions of the upper horizontal parts 24c, 25c, and the lifting platform 21 is lowered, and as shown in FIG. 8, the pillars 91 of the shelf 90 touch the floor surface 3, completing the transportation. After the transportation is completed, a gap is secured between the lowest shelf board 92 and the lifting platform 21, and the automated guided vehicle 1 is moved out of the underfloor space 9. [Explanation of symbols]

[0051] 1. Automated guided vehicle 2. Mounting means 3. Floor surface 4 Lifting means 5 Linear bushing 6. Means of transportation 7 Body frame 8 Isolation measures 9. Gap 11 Floor side stopper 12 Rack Stopper 12a Contact part 13 Rotating shaft 17 Driven Tire 21 Lifting platform 22 Placement surface 24 Slope 24a Slope 24b Lower horizontal part 24c Upper horizontal section 25 Inclined section 26 41 Shaft 42 Second Gear 43 Third Gear 45a Linear guide 45b Linear Guide 46 Rack 46a Moving support part 46b Shaft 46c Roller 47 LACK 47a Moving support 60 Motor 61 First Gear 62 Gearbox 62a Bracket 62b Arm section 62s output shaft 63 First Gear 64 Traveling tires 82 Isolation motor 82a Gear 90 Shelves 91 Pillars 92 Shelf F1 component force

Claims

1. An automated guided vehicle for transporting an article, A placement means having a lifting platform on which an article is placed and which can be raised and lowered; A lifting means for lifting and lowering the lifting platform; A traveling means having drive tires connected to a motor and in contact with a floor surface; and a separating means for separating the running tire from the floor surface, the traveling means has a first gear, the lifting means has a second gear, the first gear and the second gear are configured to mesh with each other when the traveling tire is separated from the floor surface by the separating means, The second gear is driven by the motor to raise and lower the lifting platform. Automated guided vehicle.

2. The placement means is A sloped portion is provided on the lower surface of the lift stand, the lifting means has a moving support part that supports the inclined part from below and moves in a horizontal direction by being driven by the second gear, The moving support part moves in a horizontal direction to push the inclined part upward, thereby lifting up the lifting platform.

2. The automated guided vehicle according to claim 1.

3. The inclined portions are arranged in a pair in the horizontal direction, The moving support parts are arranged in a pair in the horizontal direction, By driving the second gear, both of the movable support parts are moved in the horizontal direction, and both of the inclined parts are pushed upward.

3. The automated guided vehicle according to claim 2.

4. The lifting means is a first rack that meshes with the second gear from above and extends horizontally; a second rack that meshes with the second gear from below and extends horizontally; having Each rack is provided with the movement support portion, The second gear drives the racks to move horizontally in opposite directions. Each of the movable support parts provided on each of the racks moves in a horizontal direction to raise and lower the lifting platform.

4. The automated guided vehicle according to claim 3.

5. The inclination angle of the inclined portion is The distance of horizontal movement of the moving support is is set to be greater than the distance by which the inclined portion is raised when the moving support portion moves in the horizontal direction.

5. The automated guided vehicle according to claim 2, wherein the automated guided vehicle is a vehicle having a plurality of wheels.

6. A method for driving an automated guided vehicle for transporting an article, comprising the steps of: The automated guided vehicle is A placement means for placing an article thereon and capable of moving up and down; A lifting means for lifting and lowering the lifting platform, and a traveling means having traveling tires connected to a motor and in contact with a floor surface; and a separating means for separating the running tire from the floor surface, the traveling means has a first gear, the lifting means has a second gear, the first gear and the second gear are configured to mesh with each other when the traveling tire is separated from the floor surface by the separating means, The second gear is driven by the motor to raise and lower the placement means. A method for driving an automated guided vehicle.

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