Conveying system

Abstract

To provide a transport system that prevents the mounting platform from overrunning while facilitating system recovery. [Solution] The transport system according to this disclosure comprises a guide rail extending in the vertical direction, a mounting table engaged with the guide rail, and a lifting unit for raising and lowering the mounting table, a control unit that outputs a control signal to suppress the operation of the lifting unit when the mounting table reaches a first height, and a safety control unit that cuts off the supply of power to the lifting unit when the mounting table reaches a second height after reaching the first height.

Description

Technical Field

[0007] , ,

[0001] The present disclosure relates to a conveying system.

Background Art

[0002] Patent Document 1 discloses a safety control unit that detects an overrun of a mounting table that moves up and down along a guide rail and cuts off the supply of energy to a lifting mechanism.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is a problem that physically cutting off the supply of energy to the lifting mechanism requires a long time for the system to recover.

[0005] The present disclosure has been made in view of the above background, and an object thereof is to provide a conveying system that facilitates system recovery while preventing the overrun of the mounting table.

Means for Solving the Problems

[0008] [Figure 1] This is a perspective view showing the schematic configuration of the transport robot according to Embodiment 1. [Figure 2] This is a side view showing the schematic configuration of the transport robot according to Embodiment 1. [Figure 3] This is a block diagram showing the functional configuration of the transport robot according to Embodiment 1. [Figure 4] This is a front view showing the schematic configuration of the shelf according to Embodiment 1. [Figure 5] This is a diagram illustrating the operation of the limit switch according to Embodiment 1. [Modes for carrying out the invention]

[0009] The following describes specific embodiments applying this disclosure with reference to the drawings. However, this disclosure is not limited to the following embodiments. Also, for clarity, the following description and drawings have been simplified as appropriate.

[0010] Embodiment 1 The transport system according to Embodiment 1 will be described below with reference to the drawings. The transport system includes a transport robot for transporting goods. The transport system may further include a server for managing the transport of goods by the transport robot. In this case, some of the functions of the transport robot according to Embodiment 1 may be provided in the server. A system in which processing is completed by the transport robot may also be included in the transport system according to Embodiment 1. The transport system according to Embodiment 1 may further include shelves for storing goods.

[0011] Figure 1 is a perspective view showing the schematic configuration of the transport robot 10 according to Embodiment 1. Figure 2 is a side view showing the schematic configuration of the transport robot 10 according to Embodiment 1. Figure 3 is a block diagram showing the functional configuration of the transport robot 10 according to Embodiment 1. The transport robot 10 comprises a movable mobile unit 11, a lifting unit 12, a mounting platform 13, a telescopic arm 14, a pair of limit switches 15a and 15b, a control unit 16, and a safety control unit 17. The control unit 16 controls the mobile unit 11, the lifting unit 12, and the telescopic arm 14. The safety control unit 17 suppresses the operation of the lifting unit 12 based on the detection results from the limit switches 15a and 15b.

[0012] The mobile unit 11 comprises a mobile body 111, a pair of left and right drive wheels 112 and a pair of front and rear driven wheels 113 rotatably mounted on the mobile body 111, and a pair of motors 114 that rotate each drive wheel 112. Each motor 114 rotates each drive wheel 112 via a reduction gear or the like. Each motor 114 rotates each drive wheel 112 in response to a control signal from the control unit 16, thereby moving the mobile body 111 to any desired position. Note that the configuration of the mobile unit 11 described above is just an example and is not limited thereto. For example, the number of drive wheels 112 and driven wheels 113 of the mobile unit 11 can be arbitrary, and any configuration can be applied as long as the mobile body 111 can be moved to any desired position.

[0013] The lifting mechanism 12 raises and lowers the mounting platform 13. The lifting mechanism 12 may be configured, for example, as a telescopic extension mechanism.

[0014] The loading platform 13 is located at the tip of the lifting section 12. The loading platform 13 is a platform on which cargo can be placed, and is also referred to as the top plate. A pair of grooves 131a and 131b extending vertically are provided on the side of the loading platform 13. When the pair of grooves 131a and 131b are not distinguished from each other, they may simply be referred to as groove 131. The pair of grooves 131a and 131b are provided so as to extend from the bottom surface to the top surface of the loading platform 13. The pair of grooves 131a and 131b can engage with a pair of guide rails 23a and 23b, which will be described later.

[0015] The telescopic arm 14 is attached to the mounting table 13. The telescopic arm 14 moves a hook attached to a guide rail mechanism (not shown) inside the mounting table 13 horizontally, for example. The telescopic arm 14 pushes the luggage placed on the mounting table 13 into the shelf 20 described later and pulls out the luggage stored in the shelf 20 to the mounting table.

[0016] The limit switch 15a is provided in the groove 131a of the mounting table 13. The limit switch 15b is provided in the groove 131b of the mounting table 13. When the limit switches 15a and 15b are not distinguished from each other, they may be simply referred to as the limit switch 15. The limit switch 15 includes, for example, an actuator that mechanically displaces and a microswitch that is operated via the actuator. The limit switch 15 can detect the presence of the guide rail 23 described later in the groove 131.

[0017] Referring to FIG. 4, the shelf 20 engaged with the transport robot 10 according to Embodiment 1 will be described. FIG. 2 is a front view showing a schematic configuration of the shelf 20. In FIG. 1, the lower side of the shelf 20 is omitted from the illustration.

[0018] The shelf 20 includes a frame body 21, a pair of support members 22, and a pair of guide rails 23a and 23b. The frame body 21 has, for example, a substantially rectangular frame shape when viewed from the front as a basic form, and the front surface of the frame body 21 is open.

[0019] A pair of support members 22 extending in the depth direction are provided on the inner surface of the frame body 21. A flange protruding from the side of a luggage (e.g., a letter pack) not shown is placed on the pair of support members 22. Although not shown in FIG. 1, a plurality of pairs of support members 22 may be arranged at intervals in the vertical direction of the frame body 21.

[0020] On the front surface of the frame body 21, a pair of guide rails 23a and 23b extending in the vertical direction are provided. When not distinguishing between the guide rails 23a and 23b from each other, they may be simply referred to as the guide rail 23. The guide rail 23a engages with the groove 131a of the mounting table 13. The guide rail 23b engages with the groove 131b of the mounting table 13. When the pair of guide rails 23 engage with the pair of grooves 131, the pair of guide rails 23 engage with the mounting table 13. A gap may be formed between the lower surface of the frame body 21 and the lower ends of the pair of guide rails 23 for the transfer robot 10 in the lowered state to enter.

[0021] A groove 231a is formed at the upper end portion of the guide rail 23a, and a groove 231b is formed at the upper end portion of the guide rail 23b. The grooves 231a and 231b are recessed, for example, in the depth direction of the shelf 20. The grooves 231a and 231b extend in the vertical direction. The height of the upper end of the groove 231a is equal to the height of the upper end of the groove 231b. The height of the lower end of the groove 231a is higher than the height of the lower end of the groove 231b. The distance d indicated by the double-sided arrow indicates the difference between the height of the lower end of the groove 231a and the height of the lower end of the groove 231b. When the mounting table 13 rises to the upper end portions of the pair of guide rails 23, the actuator of the limit switch 15a enters the groove 231a, and the actuator of the limit switch 15b enters the groove 231b.

[0022] Referring to FIG. 5, the operation of the limit switch 15 will be described. First, referring to the leftmost figure in FIG. 5, the actuator of the limit switch 15 is located below the lower end of the groove 231. At this time, the state of the limit switch 15 is the on state. Subsequently, when the mounting table 13 rises, as shown in the second figure from the left in FIG. 5, the actuator of the limit switch 15 reaches the lower end of the groove 231. Subsequently, as shown in the third figure from the left in FIG. 5, the actuator of the limit switch 15 enters the groove 231, and the limit switch 15 starts to switch from the on state to the off state. Subsequently, as shown in the fourth figure from the left in FIG. 5, the actuator of the limit switch 15 moves upward within the groove 231, and the state of the limit switch 15 becomes the off state.

[0023] Referring to Figure 3, the control unit 16 may control the movement of the transport robot 10 by performing well-known controls such as feedback control and robust control based on rotation information of the drive wheels 112 detected by rotation sensors provided on the drive wheels 112. The control unit 16 may also autonomously move the transport robot 10 by controlling the movement unit 11 based on information such as distance information detected by distance sensors such as cameras and ultrasonic sensors provided on the transport robot 10, and map information of the movement environment. In addition, the control unit 16 supplies control signals for controlling the lifting unit 12 and the telescopic arm 14.

[0024] The control unit 16 is hardware-based and consists of a microcomputer, for example, a CPU 161 (Central Processing Unit) that performs control processing, calculation processing, etc., a memory 162 consisting of ROM (Read Only Memory) and RAM (Random Access Memory) that stores control programs, calculation programs, etc. executed by the CPU 161, and an interface unit (I / F) 163 that performs signal input and output with the outside. The CPU 161, memory 162, and interface unit 163 are interconnected via a data bus or the like.

[0025] The control unit 16 acquires the detection results from the limit switches 15a and 15b. When the state of the limit switch 15b switches from the ON state to the OFF state, the control unit 16 outputs a control signal to the lifting unit 12 that suppresses the operation of the lifting unit 12. The control signal may be a signal that sets the command value of the lifting speed of the mounting platform, for example, the command value of the speed of the motor included in the lifting unit 12, to zero. Alternatively, the control signal may be a signal that reduces the lifting speed of the mounting platform 13.

[0026] The distance d in Figure 4 may be set to be greater than, for example, the sum of the product of the speed of the mounting platform 13 (e.g., maximum speed) and the response time of the limit switch 15a, and the distance the mounting platform 13 moves from the time the control unit 16 outputs a control signal until the mounting platform 13 stops.

[0027] The safety control unit 17 acquires the detection results from a pair of limit switches 15a and 15b. The safety control unit 17 shuts off the power supply to the lifting unit 12 when the state of limit switch 15a switches from the ON state to the OFF state and the state of limit switch 15b switches from the ON state to the OFF state. The safety control unit 17 may include a processor, memory, etc., similar to the control unit 16. The safety control unit 17 may also be a PLC (Programmable Logic Controller). Specifically, the safety control unit 17 shuts off the power supply to the lifting unit 12. The safety control unit 17 may, for example, shut off a relay provided in the power supply path to the lifting unit 12. If a drive source such as high-pressure air or oil is used instead of power, the safety control unit 17 may shut off a valve.

[0028] If the mounting platform 13 accidentally reaches the upper ends of the pair of guide rails 23a and 23b, first the actuator of the limit switch 15b enters the groove 231b of the guide rail 23b, and the control unit 16 suppresses the movement of the lifting unit 12. If the control unit 16 is able to suppress the movement of the lifting unit 12, the safety control unit 17 does not operate, and Embodiment 1 can shorten the time required to recover the transport robot 10.

[0029] If the control unit 16 fails to suppress the movement of the lifting unit 12, the actuator of the limit switch 15a enters the groove 231a of the guide rail 23a, and the safety control unit 17 cuts off the power supply to the lifting unit 12. Therefore, even if the control unit 16 malfunctions, Embodiment 1 can safely stop the lifting unit 12. Compared to the case where the raising of the platform 13 is stopped mechanically, Embodiment 1 can reduce the risk of cargo scattering or damage to the platform 13 or the lifting unit 12.

[0030] This disclosure is not limited to the embodiments described above, and may be modified as appropriate without departing from its spirit.

[0031] For example, a pair of grooves 231a and 231b may be arranged side by side on one of the pair of guide rails 23. In this case, a pair of limit switches 15a and 15b may be arranged side by side on one of the pair of grooves 131 of the mounting base 13. Alternatively, a pair of photoreflectors may be provided instead of the pair of limit switches 15. At the upper ends of the pair of guide rails 23, a region with high reflectivity or a region with low reflectivity may be provided instead of grooves 231a and 231b. Alternatively, a pair of photoreflectors may be used to detect grooves 231a and 231b. [Explanation of symbols]

[0032] 10 Transport robots 11 Mobile unit 111 Mobile Unit 112 Drive wheels 113 Driven wheels 114 Motor 12 Lifting section 13. Mounting platform 131, 131a, 131b, 231, 231a, 231b groove 14 Extendable Arm 15, 15a, 15b limit switches 16 Control Unit 161 CPU 162 memory 163 Interface Section 17 Safety Control Unit 20 shelves 21 Frame 22 Support member 23, 23a, 23b Guide rails

Claims

1. A guide rail extending in the vertical direction, A mounting base that engages with the aforementioned guide rail, A lifting mechanism for raising and lowering the aforementioned mounting platform Equipped with, When the mounting platform reaches a first height, a control unit outputs a control signal to suppress the operation of the lifting unit, After the mounting platform reaches the first height, and then when the mounting platform reaches the second height, a safety control unit cuts off the power supply to the lifting unit. A transport system equipped with [a specific feature / feature].

2. The mounting base engages with the first guide rail and the second guide rail, The mounting base is provided with a first sensor corresponding to the first guide rail and a second sensor corresponding to the second guide rail. The first sensor detects that the aforementioned stand has reached the first height, and the second sensor detects that the aforementioned stand has reached the second height. The transport system according to claim 1.

3. A first groove is provided in the first guide rail in a height range from the first height to a predetermined height, and a second groove is provided in the second guide rail in a height range from the second height to the predetermined height. The first sensor detects the first groove, and the second sensor detects the second groove. The transport system according to claim 2.

4. The first and second sensors are limit switches. The transport system according to claim 3.

5. The safety control unit is configured to shut off the power supply when the actuator of the first sensor limit switch enters the first groove and the actuator of the second sensor limit switch enters the second groove. The transport system according to claim 4.

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