Transport System

Abstract

To provide a conveyance system improving a service life of an expandable pipe structure formed by being spirally wound with two belts.SOLUTION: A conveyance system includes: a pipe structure 100 formed by being wound with a first belt 110 and a second belt 120 arranged inside the first belt 110 in a spiral state around an axis line; a driving part 40 vertically expanding and contracting the pipe structure 100; a placing part 50 fitted to a tip end of the pipe structure 100; and a control part 70 selecting a height for stopping the placing part 50 from a plurality of candidates on the basis of a height history about a height where the placing part 50 stopped in the past.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a transport system. [Background technology]

[0002] Patent document 1 discloses a technology for forming an extension pipe by spirally guiding a first belt having engagement pins formed along opposing long sides and a second belt having engagement holes formed along opposing long sides. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-173391 Summary of the Invention [Problem to be solved by the invention]

[0004] Relatively large stress occurs at the points where the first belt and the second belt start to wind, and this stress may reduce the durability of the extension pipe.

[0005] The present disclosure has been made in consideration of such problems, and provides a conveying system that improves the lifespan of an expandable pipe structure formed by two belts wound around it in a spiral shape. [Means for solving the problem]

[0006] A transport system according to one aspect of the present disclosure includes: a pipe structure formed by spirally winding a first belt and a second belt disposed inside the first belt around an axis; a drive unit that extends and contracts the pipe structure up and down; a mounting portion attached to the tip of the pipe structure; a control unit that selects a height at which the placement unit is to be stopped from a plurality of candidates based on a height history of heights at which the placement unit has been stopped in the past; Equipped with. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to realize a conveyance system that improves the lifespan of an expandable pipe structure formed by two belts wound around it in a spiral shape. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 10 is an explanatory diagram showing the configuration of an extension device of a reference example. [Figure 2] FIG. 10 is an explanatory diagram showing the configuration of an extension device of a reference example. [Figure 3] FIG. 1 is a diagram illustrating a configuration of a transfer robot according to a first embodiment. [Figure 4] FIG. 2 is a diagram illustrating a configuration example of a transfer robot according to the first embodiment. [Figure 5] FIG. 1 is an explanatory diagram showing the configuration of a shelf according to a first embodiment. [Figure 6] 4A to 4C are diagrams illustrating an example of the operation of the transport robot according to the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Reference example> An extension device 60 of a reference example will be described with reference to Figures 1 and 2. Figure 1 is an explanatory diagram showing the configuration of an extension device 60 having a pipe structure.

[0010] The telescopic device 60 of this reference example has a pipe structure 100, a first accommodating section 10, a second accommodating section 20, a guide section 30, a drive section 40, and a mounting section 50. The pipe structure 100 is formed by spirally winding a first belt 110 and a second belt 120. The first accommodating section 10 accommodates the first belt 110. The second accommodating section 20 accommodates the second belt 120. The guide section 30 guides and spirally winds the first belt 110 and the second belt 120. The drive section 40 rotates the guide member 32 of the guide section 30. The mounting section 50 is attached to the tip of the pipe structure 100.

[0011] When the guide member 32 is driven by the drive unit 40 to rotate in one direction, the first belt 110 and the second belt 120 are guided by the guide member 32 and wound spirally, causing the pipe structure 100 to extend upward in FIG. 1 . When the guide member 32 rotates in the opposite direction, the first belt 110 and the second belt 120 are released and housed in the first housing section 10 and the second housing section 20, respectively, causing the pipe structure 100 to shorten. Instead of rotating the guide member 32, the pipe structure 100 itself may be rotated to expand or contract. The first belt 110 and the second belt 120 can be made of metal (e.g., a springy metal such as spring stainless steel). The first belt 110 and the second belt 120 may also be made of other materials, such as a deformable resin.

[0012] Fig. 2 is an explanatory diagram showing how the pipe structure 100 is formed by winding the first belt 110 and the second belt 120. In Fig. 2, for convenience of illustration, the outline of the second belt 120 is drawn with a dashed line. The upper left of Fig. 2 shows the state before winding, and the upper right shows a planar development of how the first belt 110 and the second belt 120 overlap when wound.

[0013] The pipe structure 100 is formed by spirally winding a first belt 110 and a second belt 120 disposed inside the first belt 110 around an axis CX. The first belt 110 has a first flat band portion 111 and a plurality of first engagement portions 112 arranged in multiple rows along the longitudinal direction of the first belt 110. The first flat band portion 111 is a flat band-shaped portion without any protrusions or recesses. The first engagement portions 112 are arranged in two rows at regular intervals along the longitudinal direction of the first belt 110. The second belt 120 has a second flat band portion 121 and a plurality of second engagement portions 122 arranged in multiple rows along the longitudinal direction of the second belt 120. The second flat band portion 121 is a flat band-shaped portion without any protrusions or recesses. The second engagement portions 122 are arranged in two rows at regular intervals along the longitudinal direction of the second belt 120. The second engagement portion 122 is configured to be able to engage with and disengage from the first engagement portion 112 .

[0014] In the pipe structure 100 shown in the lower part of Fig. 2, the first belt 110 is wound at a constant pitch Pt along the axis CX. The distance Le between the two rows of first engagement portions 112 along the axis CX is equal to 1 / 2 of the winding pitch Pt. The second belt 120 has the same configuration.

[0015] The first belt 110 has a width W1, and the second belt 120 has a width W2. These widths W1 and W2 are substantially equal and set to a value slightly smaller than the winding pitch Pt.

[0016] The first belt 110 and the second belt 120 are overlapped and spirally wound while being shifted from each other by half the winding pitch Pt. As a result, the two rows of first engagement portions 112 of the first belt 110 engage with the second engagement portions 122 of the two second belts 120 overlapped inside the first belt 110.

[0017] The extension device 60 can transport luggage placed on the loading section 50 in the vertical direction.

[0018] <Embodiment 1> First, we will explain the problem that the present inventors found in the telescopic device 60 of the above-mentioned reference example. The present inventors discovered that a large amount of stress occurs at the base end of the pipe structure 100, more specifically, at the point where the spiral winding of the first belt 110 and the second belt 120 begins. If the above-mentioned stress accumulates, the durability of the pipe structure 100 may be reduced. In the first embodiment, a conveying system that improves the lifespan of the pipe structure 100 is realized.

[0019] A transport system according to a first embodiment will be described below with reference to the drawings. The transport system includes a transport robot that transports luggage. The transport system may further include a server that manages the transport of luggage by the transport robot. In this case, some of the functions of the transport robot according to the first embodiment may be provided in the server. Note that a system in which processing is completed in the transport robot may also be included in the transport system according to the first embodiment.

[0020] 3 is a diagram illustrating the configuration of the transport robot 200 according to the embodiment 1. The following describes the transport robot 200 according to the embodiment 1, focusing on the differences from the extension device 60 according to the comparative example, and the same components are denoted by the same reference numerals and will not be described as appropriate.

[0021] The transport robot 200 includes an extension device 60 and a control unit 70. The extension device 60 includes a pipe structure 100, a first storage unit 10, a second storage unit 20, a guide unit 30, a drive unit 40 that rotates the guide member 32 of the guide unit 30, and a placement unit 50. A load is placed on the placement unit 50. The placement unit 50 may be provided with a groove that fits into a guide rail that extends in the vertical direction.

[0022] For example, the luggage may be transferred between the placement unit 50 and a shelf (not shown). The luggage placed on the placement unit 50 is transported, and the transported luggage is transferred to the shelf. Furthermore, the luggage transferred from the shelf to the placement unit 50 is transported by the transport robot 200.

[0023] The control unit 70 is configured as hardware centered around a microcomputer including, for example, a CPU (Central Processing Unit) 71, a memory 72, and an interface unit (I / F) 73. The CPU 71 performs control processing, arithmetic processing, etc. The memory 72 includes a ROM (Read Only Memory) that stores control programs, arithmetic programs, etc., executed by the CPU 71. The interface unit 73 inputs and outputs signals from and to the outside. The CPU 71, memory 72, and interface unit 73 are connected to one another via a data bus. The functions of the control unit 70 will be described later.

[0024] Next, a transfer robot 200a, which is an example of the transfer robot 200, will be described with reference to Fig. 4. Fig. 4 is a perspective view that schematically shows the transfer robot 200a.

[0025] As shown in FIG. 4, the transport robot 200a includes an extension device 60, a base unit 80, and a moving unit 90. The extension device 60 includes a mounting unit 50. The upper surface of the mounting unit 50 may be circular or rectangular. The base unit 80 supports the extension device 60 so that it can extend and retract. For example, swivel casters 81 are provided at the front and rear ends of the underside of the base unit 80. The base unit 80 may be covered by, for example, a cover 82.

[0026] The moving unit 90 includes left and right drive wheels 91 and a motor (not shown). The left and right drive wheels 91 and the motor are supported by the base unit 80. The transport robot 200a moves forward, backward, and turns, for example, by independently driving and rotating the left and right drive wheels 91. The transport robot 200a may operate by autonomous control or may operate according to external instructions.

[0027] FIG. 5 is an explanatory diagram showing an example configuration of a shelf 300 that stores packages. The shelf 300 stores packages (e.g., returnable boxes) not shown. The shelf 300 includes a housing 310, a support member 320, and a guide rail 330. The support member 320 supports both sides of the packages stored on the shelf 300. The guide rail 330 is engaged with a groove 51 provided in the placement unit 50. The guide rail 330 extends vertically. A gap is formed between the lower end of the guide rail 330 and the floor or the like, allowing the transport robot 200, which has lowered the placement unit 50, to enter.

[0028] The operation of the transport robot 200a to take an item in and out of the shelf 300 will be described. The transport robot 200 first lowers the height of the placement unit 50 below the height of the lower end of the guide rail 330, and enters the gap provided below the guide rail 330. The transport robot 200 then raises the placement unit 50 to align the groove 51 with the guide rail 330, and raises the placement unit 50 along the guide rail 330 to a desired height. The item is then transferred by the extendable arm 52 provided on the placement unit 50. Note that the item may be transferred by means other than the extendable arm 52.

[0029] Returning to FIG. 3, the function of the control unit 70 will be described. The control unit 70 controls the height of the placement unit 50 by sending a control signal to the drive unit 40. For example, the height of the placement unit 50 needs to be controlled when an item is transferred between the placement unit 50 and a shelf or when the height of the placement unit 50 needs to be lowered. The height of the placement unit 50 needs to be lowered, for example, when the height of the placement unit 50 needs to be lower than the height of the lower end of the guide rail. Furthermore, there are cases where the height of the placement unit 50 needs to be lowered while the transport robot 200a is traveling.

[0030] When controlling the height of the placement unit 50, the control unit 70 is configured to select one of a plurality of candidate heights for the placement unit 50. For example, the plurality of candidates are included in a height range of the placement unit 50 that allows luggage to be transferred to and from the luggage placement unit (e.g., a shelf). Also, for example, the plurality of candidates are included in a height range that is lower than a predetermined height. Each candidate may be a specific height position or a position range with a certain width.

[0031] The control unit 70 has a function (called a selection function) of selecting the height at which the mounting unit 50 is to be stopped from among a plurality of candidates based on a history (called a height history) of heights at which the mounting unit 50 has been stopped in the past. The control unit 70 can level out the stresses accumulated in the first belt 110 and the second belt 120 by referring to the height history.

[0032] For example, the control unit 70 may select, from among the multiple candidates, a candidate where the mounting unit 50 has stopped relatively few times in the past. This distributes the locations where high stress occurs in the first belt 110 and the second belt 120.

[0033] Furthermore, the control unit 70 may select a candidate height that is different from the height at which the mounting unit 50 most recently stopped. By preventing the same candidate from being selected consecutively, stress accumulation can be prevented.

[0034] When the height of the placement unit 50 is to be lowered below a predetermined height, the control unit 70 selects the height of the placement unit 50 from among a plurality of candidates included in a height range lower than the predetermined height. For example, there are cases where it is desired to lower the height of the placement unit 50 while the transfer robot 200a is traveling. There are also cases where it is desired to lower the height of the placement unit 50 below the height of the lower end of the guide rail.

[0035] When lowering the height of the mounting unit 50 below a predetermined height, the control unit 70 may preferentially select a relatively tall candidate from among the plurality of candidates. A relatively low candidate is more likely to be selected when restrictions on the height of the mounting unit 50 are strict. Therefore, by the control unit 70 preferentially selecting a relatively tall candidate, the frequency with which a plurality of candidates are selected can be leveled.

[0036] For example, the control unit 70 may set the candidate h that minimizes the value of the evaluation function f(h) shown in equation (1) as the actual command value.

[0037] f(h)=((number of stops)+log 10 (Weight)*α)-h*β···(1)

[0038] h represents each candidate. "Number of stops" represents the number of times the placement unit 50 has stopped at candidate h in the past. "Weight" represents the average weight of the luggage placed on the placement unit 50. Note that "weight" may include the weight of the placement unit 50. Also, "weight" may be a constant that does not depend on the weight of the luggage (e.g., the weight of the placement unit 50). α is a coefficient determined by the SN (Stress-Number of cycles to failure) diagram of the material forming the first belt 110 and the second belt 120. β is a weighting coefficient for preferentially selecting high-stress candidates.

[0039] First, the first term of formula (1) will be described. The first term is derived from the fact that in a typical SN curve, the common logarithm of the number of repetitions is inversely proportional to the stress. Note that if the durability of first belt 110 and second belt 120 decreases due to a mode other than fatigue failure, such as wear, formula (1) may not hold. In this case, formula (1) may be modified according to each mode.

[0040] Next, the second term of equation (1) will be explained. The second term allows candidates with higher values ​​to be selected preferentially. The weighting coefficient β may be set to an appropriate value depending on the upper limit of the "number of stops" or a predetermined height. Note that in equation (1), subtraction is used as the calculation using the first and second terms, but division or exponentiation may also be used.

[0041] 6A and 6B are diagrams illustrating an example of the operation of the transport robot 200 according to the embodiment 1. The operation of the transport robot 200 when the height of the receiver 50 is lowered below a predetermined height will be described.

[0042] First, the control unit 70 of the transfer robot 200 determines a height range that is allowable as the height of the placement unit 50 (step S11). The range is determined depending on the operation that the transfer robot 200 performs.

[0043] Next, the control unit 70 selects one of the multiple candidates included in the determined height range based on the above formula (1) etc. (step S12). Information indicating the selected candidate is passed to the driving unit 40 as a command value.

[0044] Next, the drive unit 40 lowers the placement unit 50 based on the received command value (step S13). Next, the control unit 70 measures the height at which the placement unit 50 stopped based on the detection results of sensors provided on the placement unit 50, etc., and records the measured height in the height history (step S14). When the measured value is recorded, a more accurate height history is recorded compared to when a command value is recorded. After step S14, the transport robot 200 performs the following operation.

[0045] Returning to FIG. 3 , the control unit 70 may select the height at which the placement unit 50 is to stop based additionally on the history of weights of packages previously placed on the placement unit 50 (referred to as weight history). If the package placed on the placement unit 50 is heavy, there is a possibility that a large amount of stress will be generated in the first belt 110 and the second belt 120. For example, the control unit 70 may select the height of the placement unit 50 so that it is less likely that a height at which a placement unit 50 with a heavy package has previously stopped will be selected.

[0046] Incidentally, when cargo is transferred using an extendable arm or the like provided on the placement unit 50, large stresses (e.g., compressive stress and tensile stress) are generated at the base end of the pipe structure 100, so it is desirable to distribute the locations where the stress occurs. The transport robot 200 can distribute the locations where the stress occurs by selecting the height of the placement unit 50 based on the height history. Furthermore, since this stress increases as the weight of the cargo increases, the stress accumulated in the first belt 110 and the second belt 120 can be leveled out based on the weight history.

[0047] The conveying system according to the first embodiment prevents stress from accumulating at specific points on the two belts, thereby improving the lifespan of the expandable pipe structure formed by the two belts wound around it in a spiral shape.

[0048] The transport system does not need to be configured such that all of the functional elements are integrated into the transport robot 200. For example, the selection function of the control unit 70 may be performed by a calculation unit provided in a server connected to the transport robot 200 via a network. In this case, the server transmits the selected candidate to the transport robot 200. Furthermore, the height history, weight history, etc. may be stored in the server. In this way, the transport system may be configured to include a server and the transport robot 200. The above-mentioned processor and memory may be located in the server, or in both the transport robot 200 and the server.

[0049] The above-mentioned programs include instructions (or software code) that, when loaded into a computer, cause the computer to perform one or more functions. The programs may be stored on a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable medium or tangible storage medium includes random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disc (DVD), Blu-ray® disc or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The programs may also be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, transitory computer-readable medium or communication medium includes electrical, optical, acoustic, or other forms of propagated signals.

[0050] The present disclosure is not limited to the above-described embodiment, and can be modified as appropriate within the scope of the present disclosure. [Explanation of symbols]

[0051] 10 First storage section 20 Second storage section 30 Guide section 32 Guide member 40 Drive unit 50 Placement section 51 Groove 60 Telescopic device 70 Control Unit 71 CPU 72 memory 73 Interface section 80 Base 81 Swivel Caster 82 Cover 90 Moving Part 91 Drive wheels 100 Pipe Structure 110 First Belt 111 1st flat band part 112 first engagement portion 120 Second Belt 121 2nd flat band part 122 second engagement portion 200, 200a Transport robot 300 shelves 310 Case 320 Support member 330 Guide Rail

Claims

1. a pipe structure formed by spirally winding a first belt and a second belt disposed inside the first belt around an axis; a drive unit that extends and contracts the pipe structure up and down; a mounting portion attached to the tip of the pipe structure; a control unit that selects a height at which the placement unit is to be stopped from a plurality of candidates based on a height history of heights at which the placement unit has been stopped in the past; Equipped with the control unit selects a candidate from the plurality of candidates that the placement unit has stopped at relatively less frequently in the past; a shelf for accommodating the loads to be placed on the loading section includes a support section for supporting the loads and a guide rail for guiding the loading section in a vertical direction up to the height of the support section; Each of the plurality of candidates is included in a height range lower than the lower end of the guide rail. Conveying system.

2. When the height at which the placement unit is stopped is set lower than a predetermined height, the control unit preferentially selects a relatively higher candidate from among the plurality of candidates included in a height range lower than the predetermined height. The transport system according to claim 1 .

3. The control unit selects the height at which the placement unit is to be stopped based on a weight history of weights of packages previously placed on the placement unit. The transport system according to claim 1 .

4. The control unit selects a candidate from the plurality of candidates that is different from the height at which the placement unit most recently stopped. The transport system according to claim 1 .

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