Transport vehicle

Abstract

To provide a transport vehicle which can prevent deterioration of transport efficiency of a processed object.SOLUTION: A transport vehicle travels on a transport path installed above a processing device, transports a processed object, and includes: a container configured to store the processed object; a storage area in which the container is housed; a lifting unit which moves up or down the container between the storage area and the processing device; and a determination unit which determines whether or not the processed object is stored in the container.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a transport vehicle for transporting a workpiece. [Background technology]

[0002] A wafer on which a plurality of devices are formed is divided and diced to produce device chips each including a device. A package substrate is formed by mounting a plurality of device chips on a predetermined substrate and covering and sealing the mounted device chips with a resin layer (mold resin). A package device including a plurality of packaged device chips is manufactured by dividing and dicing this package substrate. The device chips and package devices are incorporated into various electronic devices such as mobile phones and personal computers.

[0003] Workpieces such as wafers and package substrates are processed by various processing devices such as cutting devices, grinding devices, polishing devices, laser processing devices, etc. When processing a workpiece with a processing device, an operator transports a cassette containing multiple workpieces to the processing device. Then, when the cassette is set in the processing device, the processing device takes out the workpieces one by one from the cassette and processes them in order.

[0004] In recent years, a transport system has been proposed that automatically transports workpieces to processing devices. For example, Patent Document 1 discloses a method of transporting workpieces using a transport vehicle that runs on a transport path provided above multiple processing devices. The transport vehicle runs while carrying the workpieces and transports the workpieces to a predetermined processing device at a predetermined timing. This automates the transport of the workpieces and improves the efficiency of the transport operation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-161578 A Summary of the Invention [Problem to be solved by the invention]

[0006] When the workpieces are transported by the transport vehicles as described above, each transport vehicle is connected by wire or wirelessly to a controller (control unit) that controls the operation of the transport vehicles. For example, the controller outputs commands (control signals) to each transport vehicle while monitoring the transport status of the transport vehicles (the location of the transport vehicle, whether the transport vehicle is transporting or waiting, which transport vehicle is transporting what workpiece, etc.). This allows efficient transport and handover of the workpieces to be performed automatically.

[0007] However, during the operation of the transport vehicle, the transport status of the transport vehicle recognized by the controller may unintentionally differ from the actual transport status of the transport vehicle. For example, if an abnormality occurs in the processing device or the transport vehicle while transporting the workpiece, an error is issued, the transport vehicle makes an emergency stop, and the transport system is inspected. At this time, depending on the content of the error, the workpiece housed in the stopped transport vehicle is removed by an operator, and the workpiece is inspected. If the operator mistakenly forgets to return the workpiece to the transport vehicle after the inspection and restarts the transport system, the controller still recognizes that the workpiece is housed in the transport vehicle, but the workpiece is not actually housed in the transport vehicle.

[0008] When the transport status of the transport vehicle is erroneously recognized as described above, the workpiece may not be transported to the desired location at the desired timing, which may hinder smooth transport operations. For example, it may be discovered that the workpiece is not accommodated in the transport vehicle only when the transport vehicle arrives at the processing device, which is the destination, and an error is issued at the stage of handing over the workpiece. In this case, it is necessary to restart the transport of the workpiece after the transport vehicle has finished traveling, and a loss of transport time occurs due to resetting the transport schedule and retransporting the workpiece. In this way, when a situation occurs in which the transport status of the transport vehicle recognized by the controller differs from the actual transport status of the transport vehicle, the transport efficiency of the workpiece decreases, which causes a delay in the processing of the workpiece by the processing device.

[0009] The present invention has been made in consideration of such problems, and has an object to provide a transport vehicle that is capable of preventing a decrease in the transport efficiency of workpieces. [Means for solving the problem]

[0010] According to one aspect of the present invention, there is provided a transport vehicle that travels on a transport path installed above a processing device to transport a workpiece, the transport vehicle comprising a container for housing the workpiece, a storage area in which the container is stored, a lifting unit for raising and lowering the container between the storage area and the processing device, and a judgment unit for determining whether the workpiece is housed in the container.

[0011] Preferably, the determination unit has a non-contact sensor that detects the workpiece through the container. Also, preferably, the lifting unit has a hanging member connected to the container and suspending the container, a rotatable reel around which the hanging member is wound, and a motor that controls rotation of the reel, and the determination unit determines whether the container contains the workpiece based on the torque applied to the motor.

[0012] Further, preferably, an individual identification tag containing individual information of the workpiece is attached to the workpiece, and the determination unit reads the individual information from the individual identification tag. Effect of the Invention

[0013] The transport vehicle according to one aspect of the present invention has a function of automatically determining whether or not a workpiece is contained in a container mounted on the transport vehicle. This makes it possible to avoid continuing to transport the workpiece while the container is in an inappropriate state, and prevents a decrease in the efficiency of transporting the workpiece. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a plan view showing the transport system. [Diagram 2]FIG. 2 is a block diagram showing a transport system. [Diagram 3] FIG. 3(A) is a perspective view showing the top side of the transport vehicle, and FIG. 3(B) is a perspective view showing the bottom side of the transport vehicle. [Figure 4] FIG. 13 is a perspective view showing a transport vehicle that places a container on a placement area. [Diagram 5] FIG. 5(A) is a perspective view showing the container, and FIG. 5(B) is a front view showing the container. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. 8(A) is a front view showing a reel that pays out a hanging member, and FIG. 8(B) is a front view showing the reel when a container is placed on the placement area. [Figure 9] FIG. 9(A) is a front view showing the reel rotating in the reverse direction, and FIG. 9(B) is a front view showing the reel when the slack in the hanging member is being eliminated. [Figure 10] FIG. 2 is a block diagram showing a controller. [Figure 11] Figure 11(A) is an oblique view showing a workpiece unit in which an individual identification tag is attached to the workpiece, Figure 11(B) is an oblique view showing a workpiece unit in which an individual identification tag is attached to the frame, and Figure 11(C) is an oblique view showing a workpiece unit in which an individual identification tag is attached to the sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. First, a configuration example of a transport system in which a transport vehicle according to this embodiment is used will be described. Fig. 1 is a plan view showing a transport system 2.

[0016] The transport system 2 is a system for transporting a workpiece 11 above a plurality of processing devices 4 that process the workpiece 11. Although only one processing device 4 is illustrated in Fig. 1, the number of processing devices 4 included in the transport system 2 can be set arbitrarily.

[0017] There is no limitation on the type of the processing device 4. Examples of the processing device 4 include a cutting device that cuts the workpiece 11, a grinding device that grinds the workpiece 11, a polishing device that polishes the workpiece 11, a laser processing device that performs laser processing on the workpiece 11, and the like.

[0018] The cutting device includes a processing unit (cutting unit) that cuts the workpiece 11. The cutting unit includes a spindle, and an annular cutting blade is attached to the tip of the spindle. The cutting blade is rotated and cuts into the workpiece 11, thereby cutting the workpiece 11.

[0019] The grinding device includes a processing unit (grinding unit) that grinds the workpiece 11. The grinding unit includes a spindle, and an annular grinding wheel including a plurality of grinding stones is attached to the tip of the spindle. The grinding wheel is rotated while the grinding stones are brought into contact with the workpiece 11, thereby grinding the workpiece 11.

[0020] The polishing device includes a processing unit (polishing unit) that polishes the workpiece 11. The polishing unit includes a spindle, and a disk-shaped polishing pad is attached to the tip of the spindle. The polishing pad is rotated and brought into contact with the workpiece 11, thereby polishing the workpiece 11.

[0021] The laser processing device includes a processing unit (laser irradiation unit) that performs laser processing on the workpiece 11. For example, the laser irradiation unit includes a laser oscillator that pulses a laser beam of a predetermined wavelength, and a condenser that condenses the laser beam emitted from the laser oscillator. The laser beam irradiated from the laser irradiation unit is condensed on the front surface, back surface, or inside of the workpiece 11, whereby the laser processing is performed on the workpiece 11.

[0022] For example, the workpiece 11 is a disk-shaped wafer made of a semiconductor material such as single crystal silicon, and has a front surface (first surface) and a back surface (second surface) that are generally parallel to each other. The workpiece 11 is divided into a plurality of rectangular regions by a plurality of streets (planned division lines) arranged in a lattice shape so as to intersect with each other. Furthermore, devices such as ICs (Integrated Circuits), LSIs (Large Scale Integration), LEDs (Light Emitting Diodes), and MEMS (Micro Electro Mechanical Systems) devices are formed in each of the plurality of regions divided by the streets.

[0023] A cutting device or a laser processing device processes the workpiece 11 and divides it along the streets to produce a plurality of device chips, each including a device. Also, by processing the workpiece 11 before division to thin it with a grinding device or a polishing device, it is possible to obtain thinned device chips.

[0024] However, there are no limitations on the type, material, size, shape, structure, etc. of the workpiece 11. For example, the workpiece 11 may be a wafer (substrate) made of a semiconductor other than silicon (GaAs, InP, GaN, SiC, etc.), sapphire, glass, ceramics, resin, metal, etc. In addition, there are no limitations on the type, number, shape, structure, size, arrangement, etc. of devices, and the workpiece 11 does not necessarily have to have devices formed thereon.

[0025] Furthermore, the workpiece 11 may be a package substrate such as a CSP (Chip Size Package) substrate or a QFN (Quad Flat Non-leaded package) substrate. For example, a package substrate is formed by mounting a plurality of device chips on a predetermined substrate and covering and sealing the mounted device chips with a resin layer (mold resin). By dividing and individualizing the package substrate, a package device including a plurality of packaged device chips is manufactured.

[0026] When processing the workpiece 11 with the processing device 4, the workpiece 11 may be supported by an annular frame 13 for ease of handling (transporting, holding, etc.) the workpiece 11. The frame 13 is an annular member made of a metal such as SUS (stainless steel), and a circular opening is provided in the center of the frame 13, penetrating the frame 13 in the thickness direction. The diameter of the opening in the frame 13 is larger than the diameter of the workpiece 11.

[0027] A sheet 15 supporting the workpiece 11 is fixed to the workpiece 11 and the frame 13. For example, the sheet 15 is a circular tape having a diameter larger than the opening of the frame 13, and has a film-like base material and an adhesive layer (glue layer) provided on the base material. However, the sheet 15 may be a thermocompression sheet that does not have an adhesive layer (glue layer) and can be thermocompression bonded to the workpiece 11 and the frame 13.

[0028] With the workpiece 11 placed inside the opening of the frame 13, the center of the sheet 15 is affixed to the back side of the workpiece 11, and the outer periphery of the sheet 15 is affixed to the frame 13. As a result, the workpiece 11 is supported by the frame 13 via the sheet 15, and a workpiece unit (frame unit) 17 including the workpiece 11, the frame 13, and the sheet 15 is formed.

[0029] A plurality of pipes 6 are connected to the side of the processing device 4. For example, the pipes 6 correspond to a supply duct for supplying liquid or gas to the processing device 4, an exhaust duct for exhausting liquid or gas from inside the processing device 4, and the like.

[0030] A storage device (loader / unloader) 8 that stores a plurality of workpieces 11 is installed adjacent to the processing device 4. The storage device 8 stores the workpieces 11 before they are processed by the processing device 4 and the workpieces 11 after they have been processed by the processing device 4.

[0031] The transport system 2 also includes a transport path 10 installed above the multiple processing devices 4 and the storage devices 8. The transport path 10 is installed so as to span the spaces between the processing devices 4 and between the processing devices 4 and the storage devices 8. In other words, the multiple processing devices 4 and the storage devices 8 are connected via the transport path 10. An unmanned transport vehicle (transport device) 12 that transports the workpiece 11 is disposed on the transport path 10. Although two transport vehicles 12 are illustrated in FIG. 1, there is no limit to the number of transport vehicles 12 that may be disposed on the transport path 10.

[0032] The transport vehicle 12 transports the workpiece 11 between the processing devices 4 or between the processing device 4 and the storage device 8. For example, the workpiece 11 before processing that is stored in the storage device 8 is carried into the transport vehicle 12. Then, the transport vehicle 12 travels on the transport path 10 while storing the workpiece 11 received from the storage device 8, and transports the workpiece 11 to a predetermined processing device 4. In addition, the transport vehicle 12 travels on the transport path 10 while storing the processed workpiece 11 received from the processing device 4, and transports the workpiece 11 to another processing device 4 or the storage device 8.

[0033] An opening 10a is provided in the transport path 10 in a region located directly above the processing device 4 or the storage device 8. The workpieces 11 are transferred between the transport vehicle 12 and the processing device 4 and between the transport vehicle 12 and the storage device 8 through the opening 10a.

[0034] As described above, in the transport system 2, the workpiece 11 is transported by the transport vehicle 12 traveling on the transport path 10 installed above the processing device 4 and the storage device 8. This automates the transport of the workpiece 11, improving the efficiency of the transport operation. In addition, it is possible to prevent the pipes 6 connected to the side of the processing device 4 and the like from interfering with the transport of the workpiece 11, thereby achieving smooth transport of the workpiece 11.

[0035] 2 is a block diagram showing the transport system 2. The transport system 2 includes a controller (control unit, control section, control device) 14 that controls the transport system 2. The controller 14 is connected wirelessly or by wire to the components of the transport system 2 (the processing device 4, the storage device 8, the transport vehicle 12, etc.) and controls the operation of each component by outputting a control signal (command). This controls the travel of the transport vehicle 12, the transfer of the workpiece 11 between the processing device 4 and the transport vehicle 12, the transfer of the workpiece 11 between the storage device 8 and the transport vehicle 12, etc. In addition, various information (signals, data, etc.) transmitted from the components of the transport system 2 is input to the controller 14.

[0036] For example, the controller 14 is configured by a computer and includes a processing unit that performs processing such as calculations necessary for the operation of the transport system 2, and a storage unit that stores various information (data, programs, etc.) used for the operation of the transport system 2. The processing unit includes a processor such as a CPU (Central Processing Unit). The storage unit includes memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory).

[0037] Next, a description will be given of the details of the transport vehicle 12 that travels on the transport path 10 to transport the workpiece 11. Fig. 3(A) is a perspective view showing the top side of the transport vehicle 12, and Fig. 3(B) is a perspective view showing the bottom side of the transport vehicle 12.

[0038] The transport vehicle 12 includes a plate-shaped main body frame 20 on which the various components that make up the transport vehicle 12 are mounted. A pair of axles 22 are provided on both ends on the front side of the main body frame 20. The axles 22 are disposed on the underside of the main body frame 20 such that one end protrudes from the side surface of the main body frame 20, and wheels (front wheels) 24 are attached to each one end of the axles 22.

[0039] A pair of wheels (rear wheels) 26 are arranged at the rear end of the main body frame 20, spaced apart from each other in the width direction (vehicle width direction) of the main body frame 20. For example, the wheels 26 are casters that can rotate 360° around a rotation axis that is roughly parallel to the vehicle height direction of the transport vehicle 12, and are attached to the underside of the main body frame 20. The wheels 24 and 26 are wheels for traveling when the transport vehicle 12 travels on the transport path 10 (see FIG. 1).

[0040] 3(A), a drive unit 28 that drives the pair of wheels 24 is mounted on the front end of the main body frame 20. The drive unit 28 includes a pair of motors 30 that are connected to the wheels 24 via the axles 22. The motors 30 include a rotating shaft (output shaft) 30a, and generate power for rotating the wheels 24.

[0041] 3(B), a pulley 32 is fixed to the other end of the axle 22. An endless connecting member (not shown), such as a belt or chain, is wound around the rotating shaft 30a of the motor 30 and the pulley 32. This forms a power transmission mechanism that connects the axle 22 and the motor 30. The power (rotational force) generated by the motor 30 is transmitted to the wheel 24, causing the wheel 24 to rotate.

[0042] The drive unit 28 independently controls the rotation direction of the pair of wheels 24 by a pair of motors 30. When the pair of wheels 24 are rotated in the same direction, the transport vehicle 12 moves forward or backward. When the pair of wheels 24 are rotated in opposite directions, the transport vehicle 12 rotates around a rotation axis that is approximately parallel to the vehicle height direction, and the traveling direction of the transport vehicle 12 is controlled.

[0043] A battery (secondary battery) 34 that supplies power to the motor 30 and the like is connected to the drive unit 28 via a power supply wiring (not shown). For example, the battery 34 is attached to the front end of the main body frame 20, and supplies power to the motor 30 for rotating the wheels 24. A lithium ion battery or the like is used as the battery 34.

[0044] 3(B), a pair of power receiving terminals 36 connected to a battery 34 via wiring (not shown) is provided on the underside of the front end of the main body frame 20. The pair of terminals 36 is connected to a power supply terminal installed, for example, outside the transport vehicle 12. The battery 34 is charged by power supplied from the power supply terminal to the pair of terminals 36.

[0045] A storage area 38 is provided below the main body frame 20. The storage area 38 corresponds to a space surrounded by the pair of wheels 24 and the pair of wheels 26, and located above the lower ends of the wheels 24 and 26. As shown in Fig. 3(A), a container (cassette) 40 capable of accommodating one or more workpieces 11 is stored in the storage area 38. The configuration of the container 40 will be described in detail later (see Figs. 5(A) and 5(B)).

[0046] When the transport vehicle 12 transports the workpiece 11, the container 40 containing the workpiece 11 is placed in the storage area 38. At this time, the bottom surface of the container 40 is positioned higher than the bottom ends of the wheels 24 and 26. Therefore, the container 40 does not come into contact with the transport path 10 (see FIG. 1) while the transport vehicle 12 is traveling.

[0047] A lifting unit (lifting mechanism) 42 that lifts and lowers the container 40 between the storage area 38 and the processing device 4 or the accommodation device 8 (see FIG. 1) is provided in an area overlapping with the storage area 38 on the upper surface side of the main body frame 20. The lifting unit 42 lowers the container 40 stored in the storage area 38 to place it in a predetermined placement area, and lifts the container 40 placed in the placement area to store it in the storage area 38.

[0048] 4 is a perspective view showing the transport vehicle 12 which places the container 40 on the placement area (destination) 16. The lifting unit 42 includes a plurality of hanging members 44, one end of which is connected to the container 40, and a drive mechanism 46 which pays out and takes up the hanging members 44. For example, the placement area 16 corresponds to the placement surface of a placement table which is provided inside the processing device 4 or the storage device 8 (see FIG. 1) and on which the workpiece 11 is temporarily placed.

[0049] A belt having a predetermined width, a wire rope that can be reeled in and out, or the like is used as the hanging member 44. Fig. 4 shows an example in which the hanging member 44 is a belt, and the tip ends (lower ends) of four hanging members 44 are connected to four positions on the upper surface side of the container 40, respectively. However, there is no limit to the number of hanging members 44.

[0050] When the hanging member 44 is unwound by the drive mechanism 46 while the container 40 is stored in the storage area 38, the container 40 is lowered and placed in the placement area 16. When the hanging member 44 is wound up by the drive mechanism 46 while the container 40 is placed in the placement area 16, the container 40 is raised and stored in the storage area 38.

[0051] 3(B), a plurality of contact members (contact pins) 48 that come into contact with the upper surface side of the container 40 are provided on the lower surface side of the main body frame 20. The plurality of contact members 48 are formed in columnar shapes of approximately the same height, and are fixed to the main body frame 20 so as to protrude downward from the lower surface of the main body frame 20. When the container 40 is stored in the storage area 38, the upper surface side of the container 40 is supported by contacting the lower ends of the plurality of contact members 48.

[0052] For example, the contact member 48 is made of an elastic body that undergoes elastic deformation when the container 40 is pressed against it. When an elastic body is used for the contact member 48, the impact when the container 40 comes into contact with the contact member 48 is mitigated, and the container 40 and the workpiece unit 17 housed in the container 40 are less likely to be damaged. In addition, when the transport vehicle 12 travels on the transport path 10 (see FIG. 1), the contact member 48 functions as a buffer material, making it less likely that vibrations of the main body frame 20 will be transmitted to the container 40 and the workpiece unit 17.

[0053] The contact member 48 may be made of rubber (urethane rubber, silicone rubber, etc.), sponge, etc. In particular, if rubber that exerts a large frictional force between the contact member 48 and the container 40 is used, the container 40 is less likely to shift position during transportation. The contact member 48 does not necessarily need to be made of an elastic material in its entirety, and it is sufficient that at least the area (lower end) of the contact member 48 that comes into contact with the container 40 is made of an elastic material.

[0054] It is preferable that the contact members 48 contact the upper surface side of the container 40 at three or more positions. For example, as shown in Fig. 3(B), three columnar contact members 48 are provided on the main body frame 20. In this case, the upper surface of the container 40 is supported along a plane including the lower ends of the three contact members 48, making it difficult for the container 40 to tilt.

[0055] However, the shape, number, arrangement, etc. of the contact members 48 may be changed as desired. For example, a pair of linear (strip-shaped) contact members 48 arranged generally parallel to each other may be provided on the main body frame 20. Also, a plate-shaped contact member 48 made of sponge or the like may be fixed to the entire lower surface side of the main body frame 20.

[0056] A cover 50 is provided below the rear end of the main body frame 20. When the container 40 is stored in the storage area 38, the cover 50 covers the loading / unloading opening (opening 40b, see FIG. 4) for the workpiece 11 provided in the container 40. This makes it possible to prevent foreign matter from entering the container 40 while the transfer vehicle 12 is traveling, and prevents foreign matter from adhering to the workpiece 11. In addition, even if the container 40 tilts or vibrates while the transfer vehicle 12 is traveling, the cover 50 prevents the workpiece 11 from jumping out of the container 40.

[0057] A pair of first sensors 52 are provided at the front and rear ends of the main frame 20. A pair of second sensors 54 are provided at both side ends of the main frame 20. The first sensor 52 and the second sensor 54 are each mounted to face the conveying path 10 (see FIG. 1) along which the transport vehicle 12 travels, and detect marks affixed to the conveying path 10. Based on the results of detection of the marks by the first sensor 52 and the second sensor 54, the operation of the transport vehicle 12 (travel, turn, stop, etc.) is controlled.

[0058] As shown in Fig. 3(A), a pair of third sensors 56 for detecting collision of the transport vehicle 12 with an obstacle is provided on the front end side of the main body frame 20. When the front end of the transport vehicle 12 collides with an obstacle, the third sensors 56 are activated to detect the collision of the transport vehicle 12, and the transport vehicle 12 makes an emergency stop. As the third sensors 56, for example, a push button switch is used. However, there is no limitation on the type of the third sensors 56 as long as they can detect the collision of the transport vehicle 12.

[0059] A plate-shaped support base 58 fixed to the main body frame 20 is provided on the upper side of the lifting unit 42. A controller (control unit, control section, control device) 60 for controlling the transport vehicle 12, and a receiver 62 and a transmitter 64 connected to the controller 60 are provided on the support base 58.

[0060] The controller 60 is connected to the components of the transport vehicle 12 (the drive unit 28, the battery 34, the lifting unit 42, the first sensor 52, the second sensor 54, the third sensor 56, the receiver 62, the transmitter 64, etc.) and controls the operation of each component. For example, the controller 60 is configured by a computer and includes a processing unit that performs processing such as calculations necessary for the operation of the transport vehicle 12, and a storage unit that stores various information (data, programs, etc.) used for the operation of the transport vehicle 12. The processing unit is configured to include a processor such as a CPU. The storage unit is configured to include memories such as a ROM and a RAM.

[0061] The receiver 62 receives a signal (information) from the outside and inputs it to the controller 60. For example, the receiver 62 receives information (signals, data, etc.) transmitted from the controller 14 (see FIG. 2) of the transportation system 2 and inputs it to the controller 60. Then, the controller 60 controls the operation of the transportation vehicle 12 based on the information received from the receiver 62.

[0062] The transmitter 64 receives a signal (information) from the controller 60 and transmits it to the outside. For example, the controller 60 outputs information (signals, data, etc.) related to the transport vehicle 12 to the transmitter 64. Then, the transmitter 64 transmits the information received from the controller 60 to the controller 14 of the transport system 2.

[0063] Furthermore, in the transport vehicle 12 according to this embodiment, as shown in Fig. 3(B), one or more sensors (detectors) 66 for detecting the workpiece 11 contained in the container 40 are provided on the underside of the main body frame 20. The sensor 66 is a detector for detecting the workpiece 11 through the container 40, and is connected to the controller 60. The controller 60 controls the sensor 66 to detect the workpiece 11 contained in the container 40. The function of the sensor 66 will be described in detail later (see Fig. 5(B)).

[0064] The lifting unit 42, the first sensor 52, the second sensor 54, the third sensor 56, the controller 60, the receiver 62, the transmitter 64, and the sensor 66 may each be connected to the battery 34 via a power supply wiring (not shown). In this case, the lifting unit 42, the first sensor 52, the second sensor 54, the third sensor 56, the controller 60, the receiver 62, the transmitter 64, and the sensor 66 can be operated by power supplied from the battery 34.

[0065] Next, the container 40 that houses the workpiece 11 will be described in detail. Fig. 5(A) is a perspective view showing the container 40, and Fig. 5(B) is a front view showing the container 40. As an example, the container 40 that can house two types of workpiece units 17 (workpiece units 17A and 17B, see Fig. 5(B)) that differ in size and weight will be described below. Each of the workpiece units 17A and 17B includes a workpiece 11, a frame 13, and a sheet 15 (see Fig. 1).

[0066] For example, the container 40 is formed in a hexagonal shape in a plan view, and a storage section (storage space) 40a capable of storing the workpiece units 17A, 17B is provided inside the container 40. The storage section 40a is connected to the outside of the container 40 via a slit-shaped opening 40b that opens on one side surface of the container 40. The workpiece units 17 are carried into the storage section 40a through the opening 40b, and are carried out of the storage section 40a through the opening 40b.

[0067] Container 40 is configured so that workpiece units 17A and 17B can be simultaneously accommodated in accommodation portion 40a. Specifically, accommodation portion 40a of container 40 is provided with a pair of first guide rails 70 that support workpiece unit 17A, and a pair of second guide rails 72 that support workpiece unit 17B.

[0068] Each of the pair of first guide rails 70 includes a side wall 70a fixed to the upper wall 40c of the storage section 40a and a protruding portion 70b protruding from the lower end of the side wall 70a. The upper surface of the protruding portion 70b constitutes a holding surface 70c that holds the lower surface of the workpiece unit 17A. The pair of second guide rails 72 are fixed to the bottom wall 40d of the storage section 40a so as to be spaced apart from each other. The upper surface of the second guide rail 72 constitutes a holding surface 72a that holds the lower surface of the workpiece unit 17B.

[0069] The distance between the pair of first guide rails 70 is adjusted so that the pair of holding surfaces 70c can support workpiece unit 17A from below. The distance between the pair of second guide rails 72 is adjusted so that the pair of holding surfaces 72a can support workpiece unit 17B from below. However, the distance between the pair of first guide rails 70 is narrower than the distance between the pair of second guide rails 72.

[0070] For example, workpiece unit 17A includes a workpiece 11 having a diameter of 200 mm (8 inches) and a frame 13 that supports the workpiece 11. Workpiece unit 17B includes a workpiece 11 having a diameter of 300 mm (12 inches) and a frame 13 that supports the workpiece 11. The frame 13 of workpiece unit 17A has a smaller diameter and weight than the frame 13 of workpiece unit 17B.

[0071] When workpiece units 17A and 17B are carried into container 40, frame 13 of workpiece unit 17A is supported by a pair of first guide rails 70, and frame 13 of workpiece unit 17B is supported by a pair of second guide rails 72. In this way, container 40 can simultaneously accommodate two types of workpiece units 17A and 17B of different sizes.

[0072] The container 40 containing the workpieces 11 is stored in the storage area 38 of the transport vehicle 12 (see FIG. 3(A)). Then, the workpieces 11 contained in the container 40 are detected by a sensor 66 (see FIG. 3(B)) provided on the underside of the main body frame 20 of the transport vehicle 12.

[0073] Specifically, when two types of workpiece units 17A and 17B are accommodated in the container 40, a sensor 66 (sensor 66A) for detecting the workpiece unit 17A and a sensor 66 (sensor 66B) for detecting the workpiece unit 17B are mounted on the transport vehicle 12. Then, as shown in Fig. 5(B), the sensor 66A detects the workpiece unit 17A through the upper wall 40c of the container 40, and the sensor 66B detects the workpiece unit 17B through the upper wall 40c of the container 40. This makes it possible to check whether the workpiece units 17A and 17B are accommodated in the container 40.

[0074] The sensor 66A is a detector capable of detecting at least one of the workpiece 11, the frame 13, and the sheet 15 (see FIG. 1) provided in the workpiece unit 17A housed in the container 40. The installation position of the sensor 66A is set so that the sensor 66A can detect the workpiece unit 17A housed in the container 40. For example, the sensor 66A is installed so as to overlap the workpiece 11, the frame 13, or the sheet 15 of the workpiece unit 17A housed in the container 40 in the vertical direction (the vehicle height direction of the transport vehicle 12).

[0075] The sensor 66B is a detector capable of detecting at least one of the workpiece 11, the frame 13, and the sheet 15 (see FIG. 1) of the workpiece unit 17B housed in the container 40. The installation position of the sensor 66B is set so that the sensor 66B can detect the workpiece unit 17B housed in the container 40. For example, the sensor 66B is installed so as not to overlap the workpiece unit 17A and the first guide rail 70 housed in the container 40 in the vertical direction, and to overlap the workpiece 11, the frame 13, or the sheet 15 of the workpiece unit 17B housed in the container 40 in the vertical direction.

[0076] When workpiece units 17A and 17B are housed in container 40, sensor 66A detects workpiece unit 17A, and sensor 66B detects workpiece unit 17B. Sensors 66A and 66B may directly detect workpiece 11, or may indirectly detect workpiece 11 by detecting frame 13 or sheet 15.

[0077] The sensors 66A and 66B are each a non-contact type sensor capable of detecting an object without contacting the object. For example, the sensors 66A and 66B are photoelectric sensors including a light projecting unit that projects light and a light receiving unit that receives the light projected from the light projecting unit. There is no limitation on the type of the photoelectric sensor, and a light transmission type photoelectric sensor, a light reflection type photoelectric sensor, or the like can be used. The sensors 66A and 66B may also be an imaging unit (camera) equipped with an image sensor such as a CCD (Charged-Coupled Devices) sensor or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor.

[0078] Furthermore, the container 40 is configured so that the sensors 66A, 66B can detect the workpiece units 17A, 17B through the container 40. Specifically, when the sensors 66A, 66B are optical sensors such as photoelectric sensors or imaging units, the material of the container 40 is selected so that the light (detection light) received by the sensors 66A, 66B passes through the container 40. For example, when the sensors 66A, 66B are visible light sensors that receive and detect visible light, the container 40 is made of a transparent body such as plastic or glass that can transmit visible light.

[0079] However, as long as the sensors 66A, 66B can detect the workpiece units 17A, 17B through the container 40, there is no limitation on the configuration of the container 40. For example, only the area of ​​the container 40 through which the detection light passes may be made of a transparent body that transmits the detection light. Also, an opening (through hole) may be provided in the area of ​​the container 40 through which the detection light passes. In this case, the material of the other areas of the container 40 can be freely selected.

[0080] The sensors 66A, 66B generate signals (detection signals) corresponding to the detection results of the workpiece units 17A, 17B and output them to the controller 60. Then, the controller 60 determines whether or not the workpiece units 17A, 17B are accommodated in the container 40 based on the detection signals.

[0081] For example, the controller 60 detects the intensity I of the detection signals input from the sensors 66A and 66B. A ,I B and a preset reference value (threshold) of the detection signal strength I ref Then, the controller 60 compares the intensity I A is the reference value I ref If the strength I is higher than the strength I, it is determined that the workpiece 11 of the workpiece unit 17A is contained in the container 40. A is the reference value I ref If the intensity I is lower than the intensity I, it is determined that the workpiece 11 of the workpiece unit 17A is not accommodated in the container 40. B is the reference value I ref If the strength I is higher than the strength I, it is determined that the workpiece 11 of the workpiece unit 17B is contained in the container 40. B is the reference value I ref If it is lower than this, it is determined that the workpiece 11 of the workpiece unit 17B is not accommodated in the container 40.

[0082] As described above, the controller 60 and the sensors 66A, 66B automatically determine whether the workpiece 11 is contained in the container 40 and the type of the workpiece 11 contained in the container 40. That is, the controller 60 and the sensors 66A, 66B constitute a determination unit 68 that determines the containment state of the container 40.

[0083] The sensor 66 may be capable of detecting a plurality of types of workpiece units 17. For example, the transport vehicle 12 may be equipped with one sensor 66 capable of detecting both workpiece units 17A and 17B. The container 40 may be a container capable of accommodating one type of workpiece unit 17, or a container capable of accommodating three or more types of workpiece units 17.

[0084] Furthermore, the storage state of the container 40 can also be determined by a method other than detection of the workpiece 11 by the sensor 66. For example, it may be determined whether or not the workpiece 11 is stored in the container 40 based on the load when the lifting unit 42 lifts and lowers the container 40 (see FIG. 4). A method of determining the storage state of the container 40 using the lifting unit 42 will be described below.

[0085] 6 is a plan view showing the lifting unit 42. As described above, the lifting unit 42 includes a plurality of hanging members 44 that suspend the containers 40, and a drive mechanism 46 that reel in and reel in the hanging members 44.

[0086] The drive mechanism 46 includes a motor 80 having a rotating shaft (output shaft) 80a. The motor 80 is configured by a pulse motor, a servo motor, or the like, and generates the power required for unwinding and winding the hanging member 44 by rotating the rotating shaft 80a. In addition, a pair of rods (rotating shafts) 82A, 82B are provided on both sides (upper and lower sides in FIG. 6) of the motor 80. The pair of rods 82A, 82B are disposed approximately parallel to each other so as to sandwich the motor 80 in a plan view.

[0087] A pulley 84 is fixed to one end of rod 82A. An endless connecting member 86 such as a belt or chain is wound around the rotating shaft 80a of motor 80 and pulley 84. The rotating shaft 80a of motor 80, pulley 84, and connecting member 86 constitute a power transmission mechanism that transmits the power of motor 80 to rod 82A, and connects motor 80 and rod 82A. On the other hand, no pulley is provided on one end of rod 82B.

[0088] A pulley 88A is fixed to the other end of rod 82A, and a pulley 88B having the same diameter as pulley 88A is fixed to the other end of rod 82B. An endless connecting member 90 such as a belt or chain is wound around pulley 88A and pulley 88B. The pulleys 88A, 88B and connecting member 90 constitute a power transmission mechanism that transmits the power of rod 82A to rod 82B, and connects rod 82A and rod 82B.

[0089] A pair of rotatable cylindrical reels 92A around which the hanging member 44 is wound are provided at both ends of the rod 82A. A through hole (not shown) that passes through the reel 92A in the height direction is provided in the center of the reel 92A, and an end of the rod 82A is inserted into this through hole. The pair of reels 92A is not fixed to the rod 82A, but is attached in a state that allows it to rotate freely relative to the rod 82A. Therefore, when an external force is applied to the reel 92A, the reel 92A rotates about a rotation axis that is approximately parallel to the length direction of the rod 82A, independently of the rod 82A.

[0090] A cylindrical roller 94A is provided on each of the outer sides (opposite the motor 80) of the pair of reels 92A, supporting the hanging member 44. The pair of rollers 94A are disposed below the pair of reels 92A (see FIG. 7), and are supported in a freely rotatable state around a rotation axis that is approximately parallel to the longitudinal direction of the rod 82A.

[0091] A columnar pressing member (protrusion, convex portion) 96A protruding radially outward from a side surface (outer circumferential surface) of the rod 82A is fixed to the rod 82A. For example, a pair of pressing members 96A are provided between a pair of reels 92A.

[0092] The pair of reels 92A are connected to each other via a bar (shaft) 98A arranged generally parallel to the rod 82A. For example, both ends of the bar 98A are fixed to opposing surfaces of the pair of reels 92A. When the reel 92A rotates, the bar 98A rotates around the rod 82A in conjunction with the reel 92A while maintaining a state in which it is arranged generally parallel to the rod 82A.

[0093] The rod 82A and the bar 98A are connected by a biasing member 100A. For example, a spring (spiral spring) made of a metal strip wound in a spiral shape is used as the biasing member 100A. In this case, one end of the spiral spring is wound around and fixed to the center of the rod 82A. The other end of the spiral spring is fixed to the center of the bar 98A and connected to the pair of reels 92A via the bar 98A.

[0094] On the other hand, a pair of rotatable cylindrical reels 92B around which the hanging member 44 is wound are provided at both ends of the rod 82B. A through hole (not shown) that passes through the reel 92B in the height direction is provided in the center of the reel 92B, and an end of the rod 82B is inserted into this through hole. The pair of reels 92B is not fixed to the rod 82B, but is attached in a state that allows it to rotate freely relative to the rod 82B. Therefore, when an external force is applied to the reel 92B, the reel 92B rotates around a rotation axis that is approximately parallel to the length direction of the rod 82B, independently of the rod 82B.

[0095] On the outer side of the pair of reels 92B (the side opposite to the motor 80), cylindrical rollers 94B are provided, respectively, that support the hanging member 44. The pair of rollers 94B are disposed below the pair of reels 92B (see FIG. 7), and are supported in a freely rotatable state around a rotation axis that is approximately parallel to the longitudinal direction of the rod 82B.

[0096] A columnar pressing member (protrusion, convex portion) 96B protruding radially outward from a side surface (outer circumferential surface) of the rod 82B is fixed to the rod 82B. For example, a pair of pressing members 96B are provided between a pair of reels 92B.

[0097] The pair of reels 92B are connected to each other via a bar (shaft) 98B arranged generally parallel to the rod 82B. For example, both ends of the bar 98B are fixed to opposing surfaces of the pair of reels 92B. When the reel 92B rotates, the bar 98B rotates around the rod 82B in conjunction with the reel 92B while maintaining a state in which it is arranged generally parallel to the rod 82B.

[0098] The rod 82B and the bar 98B are connected by a biasing member 100B. For example, a spring (spiral spring) made of a metal strip wound in a spiral shape is used as the biasing member 100B. In this case, one end of the spiral spring is wound around and fixed to the center of the rod 82B. The other end of the spiral spring is fixed to the center of the bar 98B and connected to the pair of reels 92B via the bar 98B.

[0099] The pair of reels 92A and the pair of reels 92B each have a hanging member 44 wound around them. One end (tip end, lower end) of the hanging member 44 is connected to the container 40 (see FIG. 4), and the other end (base end, upper end) of the hanging member 44 is connected to the reels 92A and 92B. The hanging member 44 fixed to the reel 92A hangs down in contact with the outer circumferential surface (side surface) of the roller 94A. Similarly, the hanging member 44 fixed to the reel 92B hangs down in contact with the outer circumferential surface (side surface) of the roller 94B.

[0100] Fig. 7 is a front view showing the lifting unit 42. For ease of explanation, some of the components of the lifting unit 42 are omitted from Fig. 7.

[0101] The hanging member 44 wound around reel 92A is unwound from the upper side of reel 92A and supported by roller 94A. Meanwhile, the hanging member 44 wound around reel 92B is unwound from the lower side of reel 92B and supported by roller 94B. The rotation of reels 92A and 92B is controlled by controlling motor 80 with controller 60. This controls the unwounding and winding of hanging member 44, and container 40 moves up and down.

[0102] When the transport vehicle 12 travels on the transport path 10 (see FIG. 1) and reaches directly above the destination processing device 4 or storage device 8 (see FIG. 1), the lifting unit 42 pays out the hanging member 44 to lower the container 40. As a result, the container 40 passes through the opening 10a (see FIG. 1) of the transport path 10 and is placed in a predetermined location (placement area 16, see FIG. 4) inside the processing device 4 or storage device 8.

[0103] Next, a specific operation of the lifting unit 42 will be described. First, the torque of the motor 80 is controlled by the controller 60 to make the rotating shaft 80a rotatable in the rotation direction A1 (the direction indicated by the arrow A1). Then, the weight of the container 40 causes the reel 92A to rotate in the rotation direction B1 (the direction indicated by the arrow B1) in which the hanging member 44 is unwound, and the hanging member 44 wound around the reel 92A is unwound.

[0104] At this time, the bar 98A rotates in conjunction with the reel 92A and comes into contact with the pressing member 96A fixed to the rod 82A. Then, the pressing member 96A is pressed by the bar 98A, and the rod 82A rotates in conjunction with the reel 92A in the rotation direction B1.

[0105] Similarly, the reel 92B rotates in a rotation direction C1 (indicated by an arrow C1) in which the hanging member 44 is unwound due to the weight of the container 40, and the hanging member 44 wound around the reel 92B is unwound. Also, the rod 82B rotates in the rotation direction C1 in conjunction with the reel 92B.

[0106] When the hanging members 44 are unwound from the reels 92A, 92B, the container 40 descends. At this time, the speed at which the container 40 descends can be adjusted by controlling the torque of the motor 80 with the controller 60. For example, if the container 40 is heavy and the unwounding of the hanging members 44 due to the weight of the container 40 is too fast, a force is applied to the rotating shaft 80a of the motor 80 in a rotational direction A2 (the direction indicated by the arrow A2) opposite to the rotational direction A1.

[0107] The power of the rotating shaft 80a is transmitted to the rod 82A via the connecting member 86 and the pulley 84. As a result, a force is applied to the rod 82A in a rotational direction B2 (indicated by an arrow B2) opposite to the rotational direction B1. Then, a pressing member 96A fixed to the rod 82A presses the bar 98A in the rotational direction B2. As a result, a force in the rotational direction B2 is applied to the reel 92A connected to the bar 98A, and the rotation of the reel 92A in the rotational direction B1 is decelerated.

[0108] Furthermore, the power of rod 82A is transmitted to rod 82B via pulleys 88A and 88B (see FIG. 6) and connecting member 90. As a result, a force in rotational direction C2 (direction indicated by arrow C2) opposite to rotational direction C1 is applied to rod 82B. Then, pressing member 96B fixed to rod 82B presses bar 98B in rotational direction C2. As a result, a force in rotational direction C2 is applied to reel 92B connected to bar 98B, and the rotation of reel 92A in rotational direction C1 is decelerated.

[0109] 8(A) is a front view showing the reel 92A that pays out the hanging member 44. When the reel 92A rotates in the rotation direction B1 due to the weight of the container 40, the bar 98A fixed to the reel 92A rotates around the rod 82A in the rotation direction B1 and contacts the pressing member 96A. At this time, the tip of the biasing member 100A fixed to the rod 82A is pulled by the bar 98A, and the biasing member 100A deforms and contracts so as to be wound around the rod 82A.

[0110] As a result, the restoring force of the biasing member 100A acts on the bar 98A and the reel 92A, and the reel 92A is biased in the opposite direction (rotational direction B2) to the rotational direction B1. However, while the container 40 is descending, the force with which the container 40 pulls the reel 92A is stronger than the force with which the biasing member 100A biases the reel 92A, so the reel 92A rotates in the rotational direction B1 and pays out the hanging member 44. Similarly, the biasing member 100B (see FIG. 6) biases the reel 92B in the rotational direction C2 (see FIG. 7).

[0111] Then, when a predetermined amount of the hanging member 44 is unwound from each of the reels 92A and 92B, the container 40 reaches the placement area 16. FIG. 8(B) is a front view showing the reel 92A when the container 40 is placed on the placement area 16. When the container 40 is placed on the placement area 16, the weight of the container 40 no longer acts on the reel 92A. However, since the rotation of the reel 92A does not stop immediately, the hanging member 44 is slightly unwound from the reel 92A even after the container 40 is supported on the placement area 16. As a result, sagging occurs in the excessively unwound hanging member 44.

[0112] Here, when the container 40 is placed on the placement area 16, the restoring force of the biasing member 100A acts on the bar 98A, and the bar 98A is biased in the rotational direction B2. When the weight of the container 40 is not acting on the reel 92A, the bar 98A rotates in the rotational direction B2 due to the restoring force of the biasing member 100A, and the reel 92A connected to the bar 98A also rotates in the rotational direction B2 in conjunction with the bar 98A. In other words, when the container 40 is placed on the placement area 16, the reel 92A rotates in the reverse direction.

[0113] 9A is a front view showing the reel 92A rotating in the reverse direction. When the reel 92A is rotated in the rotation direction B2 by the biasing member 100A, the hanging member 44 is wound up on the reel 92A. As a result, the slack in the hanging member 44 is automatically eliminated.

[0114] 9(B) is a front view showing the reel 92A when the slack in the hanging member 44 is eliminated. The characteristics (spring constant, etc.) of the biasing member 100A are set so that a torque greater than the weight of the hanging member 44 and less than the weight of the container 40 is applied to the reel 92A. That is, when the container 40 is placed on the placement area 16, the biasing member 100A rotates the reel 92A so that the hanging member 44 is wound up and the container 40 does not leave the placement area 16. Therefore, the container 40 does not float up from the placement area 16 due to the reverse rotation of the reel 92A.

[0115] In addition, the reel 92B is also rotated in the reverse direction by the action of the biasing member 100B (see FIG. 6). This also eliminates the slack in the hanging member 44 that has been unwound from the reel 92B. The characteristics of the biasing member 100B are set in the same manner as those of the biasing member 100A.

[0116] Then, the workpiece 11 is carried out from the container 40 placed in the placement area 16. Also, the workpiece 11 is carried into the container 40 placed in the placement area 16.

[0117] When the container 40 placed on the placement area 16 is raised, the rotating shaft 80a of the motor 80 (see FIG. 7) is rotated in the rotation direction A2. Then, the power of the rotating shaft 80a is transmitted to the rod 82A, and the rod 82A rotates in the rotation direction B2. Then, the pressing member 96A provided on the rod 82A presses the bar 98A, and the reel 92A and the bar 98A rotate in the rotation direction B2. As a result, the hanging member 44 connected to the reel 92A is wound up.

[0118] Furthermore, the power of rod 82A is transmitted to rod 82B via connecting member 90, causing rod 82B to rotate in rotation direction C2. Then, pressing member 96B provided on rod 82B presses bar 98B, causing reel 92B and bar 98B to rotate in rotation direction C2. As a result, hanging member 44 connected to reel 92B is wound up. When reels 92A and 92B are wound up by hanging members 44, container 40 moves up away from placement area 16 and is stored in storage area 38 of transport vehicle 12 (see FIG. 3(A)).

[0119] Then, after the container 40 is set on the transport vehicle 12, the transport vehicle 12 travels on the transport path 10 (see FIG. 1) and transports the workpiece unit 17 housed in the container 40. When the transport vehicle 12 travels with the container 40 stored therein, a force is applied to the rotating shaft 80a of the motor 80 in the rotation direction A2 (see FIG. 7) so that the hanging member 44 is not unwound from the reels 92A, 92B due to the container 40's own weight.

[0120] As described above, the lifting and lowering of the container 40 is controlled by the lifting unit 42. Here, the torque applied to the motor 80 differs depending on the storage state of the container 40. Therefore, the storage state of the container 40 can be determined based on the torque applied to the motor 80.

[0121] Fig. 10 is a block diagram showing the controller 60. The determination of the storage state of the container 40 based on the torque of the motor 80 is automatically performed by the controller 60. That is, the controller 60 functions as a determination unit that determines the storage state of the container 40. Note that Fig. 10 also shows a schematic diagram of some of the components of the container 40 and the lifting unit 42, in addition to a block showing the functional configuration of the controller 60.

[0122] The controller 60 includes a processing unit 110 that executes processing required to determine the storage state of the container 40, and a storage unit 120 that stores various information (data, programs, etc.) used for the processing in the processing unit 110. The processing unit 110 also includes a motor control unit 112 that controls the motor 80, a detection unit 114 that detects a value corresponding to the torque of the motor 80, and a determination unit 116 that determines the storage state of the container 40.

[0123] The motor control unit 112 outputs a control signal to the motor 80 to control the number of rotations and the rotation speed of the rotating shaft 80a of the motor 80, thereby adjusting the lifting distance and the lifting speed of the container 40. Specifically, when placing the container 40 at the destination, the motor control unit 112 outputs a control signal to the motor 80 to instruct the motor 80 to lower the container 40. As a result, the container 40 descends a predetermined distance at a predetermined speed from the state stored in the transport vehicle 12 and reaches the destination. On the other hand, when transporting the container 40, the motor control unit 112 outputs a control signal to the motor 80 to instruct the motor 80 to lift the container 40. As a result, the container 40 placed at the destination rises a predetermined distance at a predetermined speed and is stored in the transport vehicle 12.

[0124] The detection unit 114 is connected to the motor 80, and calculates a value corresponding to the torque of the motor 80 (torque corresponding value) based on a signal input from the motor 80. The torque corresponding value may be the value of the torque applied to the rotating shaft 80a of the motor 80, or may be another value corresponding to the torque applied to the rotating shaft 80a of the motor 80. For example, when the torque applied to the rotating shaft 80a of the motor 80 increases, the current value of the motor 80 required to maintain the rotation speed of the rotating shaft 80a also increases. Therefore, the current value of the motor 80 can also be used as the torque corresponding value.

[0125] The torque corresponding value detected by the detection unit 114 is output to the determination unit 116. The detection unit 114 may output a torque corresponding value measured by a predetermined sensor built into or connected to the motor 80 to the determination unit 116, or may calculate a torque corresponding value based on information (signal) input from the motor 80 to the detection unit 114 and output the calculated torque corresponding value to the determination unit 116.

[0126] A specific method for measuring the torque corresponding value can be appropriately selected. For example, when the container 40 is stored in the transport vehicle 12, the motor control unit 112 controls the motor 80 to pay out the hanging member 44 by a predetermined amount at a predetermined speed. As a result, the container 40 moves down a predetermined amount at a predetermined speed and then stops. Then, the torque and current value of the motor 80 when the container 40 stops are detected by the detection unit 114 as the torque corresponding value. However, the torque and current value of the motor 80 while the container 40 is rising or falling may also be detected as the torque corresponding value.

[0127] The determination unit 116 determines the storage state of the container 40 based on the torque corresponding value input from the detection unit 114. For example, the determination unit 116 determines whether or not the workpiece 11 is stored in the container 40 and / or the type of the workpiece 11 stored in the container 40 by comparing the torque corresponding value with a predetermined reference value (threshold value) set in advance.

[0128] For example, consider a case where the size and weight of workpiece unit 17A (see FIG. 5(B)) housed in container 40 is smaller than that of workpiece unit 17B (see FIG. 5(B)). In this case, the torque applied to motor 80 when workpiece unit 17A and workpiece unit 17B (see FIG. 5(B)) are not housed in container 40 is set to T0, and the torque applied to motor 80 when only workpiece unit 17A is housed in container 40 is set to T A The torque applied to the motor 80 when only the workpiece unit 17B is accommodated in the container 40 is T B When the workpiece unit 17A and the workpiece unit 17B are accommodated in the container 40, the torque applied to the motor 80 is T AB Then, the relationship between each torque is T0 <T A <T B <T AB That is, the torque applied to the motor 80 varies depending on the storage state of the container 40.

[0129] So, for example, the reference value of torque is Tref1 (T0 <T ref1 <T A ), T ref2 (T A <T ref2 <T B ), T ref3 (T B <T ref3 <T AB ) is set and stored in advance in the storage unit 120. The determination unit 116 then determines whether the torque T of the motor 80 detected by the detection unit 114 is a reference value T ref1 , T ref2 , T ref3 Compare with each other.

[0130] The torque T of the motor 80 is T ref1 If the torque T of the motor 80 is smaller than T ref1 If it is greater than , the determination unit 116 determines that the workpiece unit 17 is contained in the container 40. This makes it possible to determine whether or not the workpiece unit 17 (workpiece 11) is contained in the container 40.

[0131] In addition, when the workpiece units 17 are accommodated in the container 40, the type and number of the workpiece units 17 (workpieces 11) are also determined. ref1 Larger than T ref2 If the torque T of the motor 80 is smaller than T ref2 Larger than T ref3 If the torque T of the motor 80 is smaller than T ref3 If it is greater than , determining unit 116 determines that container 40 contains workpiece unit 17A and workpiece unit 17B.

[0132] If the judgment result by the judging unit 116 indicates that the assumed storage state of the container 40 differs from the actual storage state of the container 40, the controller 60 transmits an error to the controller 14 (see FIG. 2) via the transmitter 64 (see FIG. 3(A)). This notifies the controller 14 of an abnormality in the storage state of the container 40 in the transport vehicle 12.

[0133] The storage state of the container 40 may be determined automatically at a preset timing, or may be determined whenever a command for inspection is sent from the controller 14 (see FIG. 2) to the transport vehicle 12. For example, the storage state of the container 40 is inspected immediately before or immediately after the container 40 is stored in the transport vehicle 12, while the transport vehicle 12 is transporting the container 40, or immediately before or immediately after the container 40 is placed in the placement area 16 (see FIG. 4).

[0134] Furthermore, when an abnormality occurs in the transport system 2 (see Figs. 1 and 2) and the transport vehicle 12 makes an emergency stop, the storage state of the container 40 may be determined before the transport vehicle 12 resumes transport of the workpieces 11 after the abnormality is resolved. This makes it possible to check whether the appropriate workpieces 11 are stored in the transport vehicle 12 before transport is resumed, even if the workpieces 11 are taken in or out while the transport vehicle 12 is stopped, and prevents erroneous transport.

[0135] As described above, the transport vehicle 12 according to this embodiment has a function of autonomously determining whether or not the workpiece 11 is contained in the container 40 mounted on the transport vehicle 12. This makes it possible to avoid continuing the transport of the workpiece 11 while the container 40 is in an inappropriate state, and prevents a decrease in the transport efficiency of the workpiece 11.

[0136] In the present embodiment, an example has been described in which the presence or absence of the workpiece 11 is detected by the sensor 66 when determining the storage state of the container 40 (see FIG. 5(B)). However, when inspecting the storage state of the container 40, in addition to detecting the workpiece 11, individual information of the workpiece 11 may be read.

[0137] 11(A) is a perspective view showing a workpiece unit 17 in which an individual identification tag 19 is attached to a workpiece 11. The workpiece 11 may be attached with an individual identification tag 19 indicating individual information (identification information) of the workpiece 11.

[0138] The individual information of the workpiece 11 is information for identifying the workpiece 11, and includes various information related to the workpiece 11 (such as the shape, material, dimensions, structure, manufacturer, date of manufacture, and processing history of the workpiece 11). An individual identification tag 19 including the individual information of the workpiece 11 is attached to, for example, the outer periphery of the workpiece 11.

[0139] There is no restriction on the type of individual identification tag 19 as long as it is possible to record the individual information of the workpiece 11. For example, an individual identification mark such as a character string (individual ID) consisting of a string of numbers, alphabets, symbols, etc., a barcode, or a two-dimensional code is attached to the workpiece 11 as the individual identification tag 19. In this case, the individual identification mark may be printed directly on the workpiece 11, or a tag such as a sticker with the individual identification mark attached may be attached to the workpiece 11. The individual identification tag 19 may also be an IC tag, an RFID (Radio Frequency Identification) tag, or the like, in which the individual information of the workpiece 11 is recorded.

[0140] The judgment unit 68 (see FIG. 5(B)) includes a reader (reading unit) that reads the individual information of the workpiece 11 from the individual identification tag 19. For example, the sensor 66 has a function of reading the individual information of the workpiece 11 in addition to the function of detecting the workpiece 11. In this case, the sensor 66 also functions as a reader. However, the transport vehicle 12 may be equipped with a dedicated reader for reading the individual information of the workpiece 11 separately and independently from the sensor 66.

[0141] The type of reader is appropriately selected depending on the type of the individual identification tag 19. For example, if the individual identification tag 19 is a character string, a barcode, a two-dimensional code, or the like, the reader may be an OCR (Optical Character Recognition Reader), a barcode reader, a two-dimensional code reader, or the like. Also, if the individual identification tag 19 is an IC tag or an RFID tag, the reader may be an IC reader or an RFID reader.

[0142] When determining the storage state of the container 40, the sensor 66 detects the workpiece 11, and the reader reads the individual information of the workpiece 11 from the individual identification tag 19. The controller 60 then stores the read individual information in the memory unit 120 (see FIG. 10) and collates the individual information as necessary. This makes it possible to confirm whether the desired workpiece 11 is stored in the container 40.

[0143] The timing for reading the individual information can be set freely, and does not necessarily have to coincide with the timing for detecting the workpiece 11 by the sensor 66. For example, just after the workpiece 11 is placed in the container 40, only the reading of the individual information may be performed.

[0144] However, there may be cases where there is no surplus space on the workpiece 11 for attaching the individual identification tag 19. Also, there may be cases where the area of ​​the workpiece 11 to which the individual identification tag 19 is attached is processed (cutting, laser processing, etc.), making it difficult to read the individual information from the individual identification tag 19. For this reason, the individual identification tag 19 may be attached to the frame 13 or the sheet 15.

[0145] Fig. 11(B) is a perspective view showing the workpiece unit 17 with the individual identification tag 19 attached to the frame 13, and Fig. 11(C) is a perspective view showing the workpiece unit 17 with the individual identification tag 19 attached to the sheet 15. Even if there is a problem in attaching the individual identification tag 19 to the workpiece 11, it becomes possible to read the individual information of the workpiece 11 by attaching the individual identification tag 19 to the frame 13 or the sheet 15. The individual identification tag 19 may be attached to the workpiece 11 and the frame 13, or to the workpiece 11 and the sheet 15. Furthermore, the individual identification tag 19 may be attached to each of the workpiece 11, the frame 13, and the sheet 15.

[0146] In addition, the structures, methods, etc. according to the above-described embodiments can be modified as appropriate without departing from the scope of the object of the present invention. [Explanation of symbols]

[0147] 11 Workpiece 13 Frame 15 sheets 17, 17A, 17B Workpiece unit (frame unit) 19 Individual Identification Tags 2. Transport System 4 Processing equipment 6 Piping 8 Storage equipment (loader / unloader) 10 Transport path 10a opening 12 Transport vehicle (transportation device) 14 Controller (control unit, control section, control device) 16 Placement area (destination) 20 Main frame 22 Axles 24 Wheels (front wheels) 26 wheels (rear wheel) 28 Drive unit 30 Motor 30a Rotating shaft (output shaft) 32 Pulley 34 Battery (secondary battery) 36 Terminals 38 Storage 40 Container (Cassette) 40a Storage section (storage space) 40b opening 40c upper wall 40d bottom wall 42 Lifting unit (lifting mechanism) 44 Suspension member 46 Drive mechanism 48 Contact member (contact pin) 50 Cover 52 First Sensor 54 Second Sensor 56 3rd Sensor 58 Support stand 60 Controller (control unit, control section, control device) 62 Receiver 64 Transmitter 66A, 66B Sensor (detector) 68 Judgment Unit 70 First guide rail 70a side wall 70b Protrusion 70c holding surface 72 Second guide rail 72a Holding surface 80 Motor 80a Rotating shaft (output shaft) 82A, 82B Rod (rotating shaft) 84 Pulley 86 Connecting member 88A, 88B Pulley 90 Connecting member 92A, 92B Reel 94A, 94B Roller 96A, 96B Pressing member (projection, convex part) 98A, 98B Bar (shaft) 100A, 100B Pressing member 110 Processing section 112 Motor control unit 114 Detection unit 116 Judgment section 120 Storage section

Claims

1. A transport vehicle that travels on a transport path installed above a processing device to transport a workpiece, A container for accommodating the workpiece; a storage area in which the container is stored; a lifting unit for lifting the container between the storage area and the processing device; and a determination unit that determines whether the workpiece is contained in the container.

2. 2. The transport vehicle according to claim 1, wherein the determination unit has a non-contact sensor that detects the workpiece through the container.

3. the lifting unit includes a hanging member connected to the container and suspending the container, a rotatable reel around which the hanging member is wound, and a motor for controlling rotation of the reel; 2. The transport vehicle according to claim 1, wherein the determination unit determines whether the workpiece is contained in the container based on a torque applied to the motor.

4. An individual identification tag including individual information of the workpiece is attached to the workpiece; 4. The transport vehicle according to claim 1, wherein the determination unit reads the individual information from the individual identification tag.

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