Apparatus and method for conveying polycrystalline silicon

Abstract

By detecting polycrystalline silicon with high accuracy using a sensor, polycrystalline silicon to be unloaded is reliably unloaded to the outside of a conveyance unit. This polycrystalline silicon conveyance apparatus (1) comprises: a conveyance unit (30) that has an unloading end (31) from which polycrystalline silicon (S) is unloaded, and conveys the polycrystalline silicon (S) to unload the polycrystalline silicon (S) to the outside from the unloading end (31); a first sensor (12) for detecting the polycrystalline silicon (S) from a plurality of directions on the conveyance unit (30); and a control unit (20) that controls the driving of the conveyance unit (30) on the basis of the result of the polycrystalline silicon (S) detected by the first sensor (12).

Description

Polycrystalline silicon transport device and polycrystalline silicon transport method

[0001] The present invention relates to a polycrystalline silicon transport device and a polycrystalline silicon transport method.

[0002] Patent Document 1 discloses a fruit feeding device that includes a sensor that detects fruit when the fruit comes into contact with a sensor and automatically controls the amount of fruit fed based on the detection result of the sensor. Patent Document 2 discloses a waste plastic sorting device that includes a passage sensor that detects the passage of waste plastic.

[0003] Japanese Patent Publication No. 59-127685 Japanese Patent Publication No. 2002-018364

[0004] When considering the conveyance and detection of irregularly shaped objects, the fruit feeding device disclosed in Patent Document 1 has the problem of being unable to detect small objects that do not come into contact with the sensor. Also, the waste plastic sorting device disclosed in Patent Document 2 has the problem of being unable to detect waste plastic with sufficient accuracy because it uses a passing sensor that detects waste plastic from one direction.

[0005] An object of one aspect of the present invention is to reliably transport polycrystalline silicon to the outside of a transport unit by detecting polycrystalline silicon with high accuracy using a sensor.

[0006] In order to solve the above problems, one embodiment of the present invention provides a polycrystalline silicon transport device comprising: a transport unit having an unloading end from which polycrystalline silicon is unloaded, which transports the polycrystalline silicon and unloads it from the unloading end to the outside; a first sensor located above the transport unit which detects the polycrystalline silicon from multiple directions; and a control unit which controls the driving of the transport unit based on the detection results of the polycrystalline silicon by the first sensor.

[0007] A method for transporting polycrystalline silicon according to one embodiment of the present invention includes a transport step of transporting polycrystalline silicon using a transport unit having an outlet end from which the polycrystalline silicon is transported and transporting the polycrystalline silicon to the outside from the outlet end, a detection step of detecting the polycrystalline silicon from multiple directions on the transport unit, and a control step of controlling the operation of the transport unit based on the detection results of the polycrystalline silicon by the detection step.

[0008] According to one aspect of the present invention, by detecting the polycrystalline silicon with high accuracy using a sensor, the polycrystalline silicon to be unloaded can be reliably unloaded to the outside of the transport section.

[0009] 1 is a schematic diagram showing an example of the configuration of a transport device for polycrystalline silicon according to an embodiment of the present invention; FIG. 2 is a functional block diagram showing an example of the configuration of the transport device shown in FIG. 1; FIG. 3 is a diagram for explaining a transport unit and a first sensor provided in the transport device shown in FIG. 1; FIG. 4 is a schematic diagram for explaining the operation of the transport device shown in FIG. 1; FIG. 5 is a flow diagram showing an example of an operation of supplying polycrystalline silicon to the transport unit provided in the transport device shown in FIG. 1; FIG. 6 is a flow diagram showing an example of an operation of the transport unit provided in the transport device shown in FIG. 1; FIG. 7 is a flow diagram showing an example of an operation of a first holding unit provided in the transport device shown in FIG. 1; FIG. 8 is a flow diagram showing an example of an operation of a second holding unit provided in the transport device shown in FIG. 1; and FIG. 9 is a flow diagram showing an example of an operation of a mounting table provided in the transport device shown in FIG.

[0010] An embodiment of the present invention will be described in detail below. However, the following description is merely an example of a transport device 1 for polycrystalline silicon S according to the present invention, and the technical scope of the present invention is not limited to the following description and the contents of FIGS. 1 to 9 .

[0011] [Overview of the Conveying Device] Polycrystalline silicon S manufactured in a rod shape by the Siemens method or the like is crushed so that it can be easily used as a raw material, and is then inspected for quality problems in the form of lumps of a predetermined size. The predetermined size refers to a size with a maximum side length of 10 mm to 150 mm. The maximum side length refers to the distance between the two furthest points on the outer shape of the polycrystalline silicon S.

[0012] The polycrystalline silicon S is inspected by photographing the polycrystalline silicon S with an imaging unit such as a camera and, for example, visually observing the photographed image of the polycrystalline silicon S. The polycrystalline silicon S may also be inspected by combining the photographed image of the polycrystalline silicon S with AI (Artificial Intelligence). The transport device 1 supplies the polycrystalline silicon S to a position where the imaging unit can photograph the polycrystalline silicon S.

[0013] [Polycrystalline Silicon Transfer Device] Fig. 1 is a schematic diagram showing an example of the configuration of a transfer device 1 according to an embodiment of the present invention. Dotted lines in Fig. 1 indicate the detection ranges of each sensor. Fig. 2 is a functional block diagram showing an example of the configuration of the transfer device 1 shown in Fig. 1. As shown in Figs. 1 and 2, the transfer device 1 includes a transfer unit 30, a first sensor 12, an upper stage sensor 13, a lower stage sensor 14, a third sensor 11, a fourth sensor 15, a control unit 20, a first holding unit 40, a second holding unit 50, a mounting table 60, and a wall unit 70.

[0014] The conveying device 1 controls the operation of the conveying section 30 based on the inspection results of the first sensor 12 that detects the polycrystalline silicon S from multiple directions on the conveying section 30, thereby enabling the amorphous polycrystalline silicon S to be reliably transported outside the conveying section 30.

[0015] [Polycrystalline Silicon Transfer Device] In the transfer device 1, the transfer unit 30 is disposed at the top, and the first holding unit 40, the second holding unit 50, and the mounting table 60 are disposed in this order from the transfer unit 30 downward. That is, the mounting table 60 is disposed at the bottom. The polycrystalline silicon S is carried out one by one from the transfer unit 30. The polycrystalline silicon S moves from the top to the bottom of the transfer device 1, in this order: the transfer unit 30, the first holding unit 40, the second holding unit 50, and the mounting table 60.

[0016] (Control Unit) The control unit 20 controls the driving of the transport unit 30, the first holding unit 40, the second holding unit 50, and the mounting table 60 based on the detection results of the first sensor 12, the upper sensor 13, the lower sensor 14, the third sensor 11, and the fourth sensor 15. The functions of the control unit 20 may be realized by a CPU (Central Processing Unit) executing a program stored in a storage unit (not shown). The control of the control unit 20 will be described in detail later.

[0017] (Transportation Section) Polycrystalline silicon S formed into chunks of a predetermined size is transported into the transport section 30 from outside the transport device 1. The polycrystalline silicon S transported into the transport section 30 is formed into chunks of a predetermined size by crushing polycrystalline silicon manufactured into a rod shape by the Siemens method or the like so that it can be easily used as a raw material.

[0018] The transport unit 30 has a discharge end 31 from which the polycrystalline silicon S is discharged, and transports the polycrystalline silicon S and discharges the polycrystalline silicon S to the outside from the discharge end 31. The transport unit 30 includes a vibrating feeder 32 that vibrates to transport the polycrystalline silicon S. The control unit 20 controls the vibrating feeder 32.

[0019] The conveying section 30 has conveying surfaces 32 a, 32 b that are inclined relative to a horizontal plane. When the conveying section 30 is viewed from the discharge end 31 side, the conveying surfaces 32 a, 32 b are V-shaped, and the conveying surfaces 32 a, 32 b form valleys 32 c. When the vibrating feeder 32 vibrates, the polycrystalline silicon S is conveyed in the conveying direction D1 along the valleys 32 c.

[0020] The vibrating feeder 32 vibrates obliquely upward relative to the conveying direction D1. Specifically, the vibration direction of the vibrating feeder 32 is between the direction from the inlet end 33 toward the outlet end 31 of the conveying unit 30 and the vertically upward direction perpendicular to the horizontal plane. The vibrating feeder 32 is, for example, a vibrating feeder that vibrates using a vibrator or an electromagnetic feeder that vibrates using an electromagnet. By using the vibrating feeder 32 as the conveying unit 30 that conveys the polycrystalline silicon S, it is easy to control the discharge of the polycrystalline silicon S outside the conveying unit 30.

[0021] (Third Sensor) The third sensor 11 detects the presence of polycrystalline silicon S being carried in near the carry-in end 33 opposite the carry-out end 31 of the transport section 30. The detection result of the third sensor 11 is output to the control section 20. As shown in FIG. 1 , it is desirable to provide one third sensor 11, but multiple third sensors 11 may be provided. The third sensor 11 may be the same sensor as the laser sensor 12a described below. The control section 20 can determine whether polycrystalline silicon S has been carried into the transport section 30 based on the detection result of the polycrystalline silicon S by the third sensor 11.

[0022] The first sensor 12 detects the polycrystalline silicon S from multiple directions on the transport unit 30. The detection results of the first sensor 12 are output to the control unit 20. The first sensor 12 is a plurality of laser sensors 12a, 12b, and 12c that are provided to detect the polycrystalline silicon S from different directions.

[0023] Furthermore, the first sensor 12 detects the polycrystalline silicon S from a plurality of directions in the vicinity of the discharge end 31 from which the polycrystalline silicon is discharged. Specifically, at least one of the laser sensors 12a to 12c detects the presence of the polycrystalline silicon S in the vicinity of the discharge end 31.

[0024] This allows the control unit 20 to accurately recognize the polycrystalline silicon S immediately before it is carried out to the outside of the transport unit 30. Therefore, the polycrystalline silicon S detected by the first sensor 12 is immediately carried out to the outside of the transport unit 30, and therefore, after the polycrystalline silicon S is carried out to the outside of the transport unit 30, the first sensor 12 can detect the polycrystalline silicon S to be carried next. Therefore, based on the detection result of the polycrystalline silicon S by the first sensor 12, the control unit 20 can control the driving of the transport unit 30 so as to smoothly transport the polycrystalline silicon S.

[0025] Fig. 3 is a diagram for explaining the conveying unit 30 and the first sensor 12 included in the conveying device 1 shown in Fig. 1. Fig. 3 is a diagram of the conveying unit 30 as viewed from the discharge end 31 side. Reference numeral 3001 in Fig. 3 is a diagram showing a case where one laser sensor 12a is provided, and reference numeral 3002 in Fig. 3 is a diagram showing a case where multiple laser sensors 12a to 12c are provided.

[0026] Laser sensor 12a emits a laser beam toward valley 32c (see FIG. 1) and measures the distance to the target object using the laser beam. Laser sensor 12a then detects the presence of polycrystalline silicon S transported to valley 32c by detecting that the measured distance falls within a predetermined range.

[0027] 3, if only one laser sensor 12a detects the polycrystalline silicon S near the discharge end 31, there is a possibility that the presence of the polycrystalline silicon S cannot be detected. This is because the polycrystalline silicon S has an irregular shape, and depending on the location where the laser light emitted from the laser sensor 12a hits the polycrystalline silicon S, the distance measured by the laser sensor 12a may not be within a predetermined range, and the presence of the polycrystalline silicon S may not be detected.

[0028] 3, the conveyance device 1 employs a plurality of laser sensors 12a to 12c as the first sensor 12, which are arranged to detect the polycrystalline silicon S from different directions. This allows the use of laser sensors that are less expensive than image sensors, etc., and reduces the manufacturing cost of the conveyance device 1.

[0029] Furthermore, in the conveying unit 30, the amorphous polycrystalline silicon S is conveyed while vibrating by the vibrating feeder 32, so the distance measured by the laser light emitted from the laser sensor is likely to change due to vibration, which may reduce the accuracy of detecting the presence of the polycrystalline silicon S. In contrast, by providing multiple laser sensors 12a to 12c, the polycrystalline silicon S can be detected by multiple laser sensors, so that the presence of the polycrystalline silicon S can be detected with high accuracy even if the measurement distance of each laser sensor changes due to vibration. Therefore, it is possible to easily control the conveyance of the polycrystalline silicon S to the outside of the conveying unit 30 and to accurately detect the presence of the amorphous polycrystalline silicon S at the same time.

[0030] When the first sensor 12 is a plurality of laser sensors, the first sensor 12 is preferably three laser sensors 12a to 12c, as indicated by reference numeral 3002 in Fig. 3. The laser sensor 12a is preferably positioned so that the laser light from the laser sensor 12a extends in a substantially vertical direction and is irradiated onto the bottom of the valley 32c between the conveying surfaces 32a and 32b.

[0031] Furthermore, it is desirable that the laser sensor 12b is disposed so that the laser light from the laser sensor 12b is irradiated along the conveying surface 32a toward the bottom of the valley 32c, and it is desirable that the laser sensor 12c is disposed so that the laser light from the laser sensor 12c is irradiated along the conveying surface 32b toward the bottom of the valley 32c.

[0032] Laser sensors 12b and 12c may be the same sensor as laser sensor 12a. By arranging laser sensors 12a to 12c in this manner, the distance to polycrystalline silicon S can be measured from multiple directions, and therefore polycrystalline silicon S at discharge end 31 can be detected with high accuracy even when transport unit 30 transports polycrystalline silicon S by vibration.

[0033] The first sensor 12 may be an image sensor that includes a camera capable of photographing the polycrystalline silicon S in three dimensions and detects the polycrystalline silicon S from multiple directions using 3D images acquired by photographing the polycrystalline silicon S with the camera. In this case, the first sensor 12 may be a single image sensor.

[0034] (First Holding Unit) The first holding unit 40 is capable of holding the polycrystalline silicon S carried out from the carrying-out end 31. Furthermore, the first holding unit 40 releases the hold of the polycrystalline silicon S, causing the polycrystalline silicon S to fall onto the second holding unit 50. The driving of the first holding unit 40 is controlled by the control unit 20.

[0035] Fig. 4 is a schematic diagram for explaining the operation of the conveying device 1 shown in Fig. 1. As shown in Fig. 1 and Fig. 4, the first holding unit 40 has a movable unit 41 and a support unit 41a. The movable unit 41 moves in a substantially horizontal direction under the control of the control unit 20.

[0036] A support portion 41a is provided at the end of the movable portion 41 on the wall portion 70 side. The support portion 41a is provided on the movable portion 41 so as to be inclined with respect to the horizontal direction so as to be able to support the polycrystalline silicon S carried out from the carry-out end portion 31. A holding space 42 is formed between the support portion 41a and the wall portion 70 by the lower end of the support portion 41a being in contact with a plate-shaped wall portion 70 that is arranged in the vertical direction below the carry-out end portion 31. The polycrystalline silicon S carried out from the carry-out end portion 31 enters the holding space 42 and is held by the support portion 41a and the wall portion 70.

[0037] Although the support portion 41 a is illustrated as a single plate in FIGS. 1 and 4 , the support portion 41 a may be, for example, box-shaped, with an open top, and forming a holding space 42 between the support portion 41 a and the wall portion 70, so as to be able to hold the polycrystalline silicon S more reliably.

[0038] Furthermore, when the movable part 41 moves so that the support part 41 a moves away from the wall part 70, the polycrystalline silicon S falls from the support part 41 a onto the second holding part 50. In other words, the holding of the polycrystalline silicon S by the first holding part 40 is released, and the polycrystalline silicon S falls from the first holding part 40 onto the second holding part 50.

[0039] (Upper stage sensor) Upper stage sensor 13 is an example of a second sensor, and detects polycrystalline silicon S falling from discharge end 31 to first holding unit 40. The detection result of upper stage sensor 13 is output to control unit 20. Upper stage sensor 13 is disposed between transport unit 30 and lower stage sensor 14. The detection range of upper stage sensor 13 is preferably a portion of the horizontal plane located between transport unit 30 and support unit 41 a that overlaps with support unit 41 a in a state where holding space 42 is formed in the vertical direction.

[0040] The upper sensor 13 may be, for example, a photoelectric sensor having a light-emitting portion (not shown) that emits planar light and a light-receiving portion that receives the light emitted from the light-emitting portion that is reflected by the polycrystalline silicon S. While it is desirable that one upper sensor 13 is provided as shown in Figures 1 and 4, a plurality of upper sensors 13 may be provided.

[0041] (Second Holding Unit) The second holding unit 50 is capable of holding the polycrystalline silicon S that falls downward from the first holding unit 40, that is, it is capable of holding the polycrystalline silicon S that has been carried out from the carry-out end 31. The second holding unit 50 also releases the hold on the polycrystalline silicon S, causing the polycrystalline silicon S to fall onto the mounting table 60. The driving of the second holding unit 50 is controlled by the control unit 20. As shown in FIGS. 1 and 4, the second holding unit 50 has a movable unit 51 and a support unit 51a. The movable unit 51 is movable in a substantially horizontal direction under the control of the control unit 20.

[0042] A support portion 51a is provided on the end of the movable portion 51 on the wall portion 70 side. The support portion 51a is provided on the movable portion 51 so as to be inclined with respect to the horizontal direction so as to be able to support the polycrystalline silicon S dropping from the first holding portion 40. A holding space 52 is formed between the support portion 51a and the wall portion 70 as the lower end of the support portion 51a comes into contact with the wall portion 70. The polycrystalline silicon S dropping from the first holding portion 40 enters the holding space 52 and is held by the support portion 51a and the wall portion 70.

[0043] Although the support portion 51 a is illustrated as a single plate in FIGS. 1 and 4 , the support portion 51 a may be, for example, a box-like shape that forms a holding space 52 between itself and the wall portion 70 and is open at the top so that the polycrystalline silicon S can be securely held.

[0044] Furthermore, when the movable part 51 moves so that the support part 51 a moves away from the wall part 70, the polycrystalline silicon S falls from the support part 51 a onto the mounting table 60. In other words, the holding of the polycrystalline silicon S by the second holding part 50 is released, and the polycrystalline silicon S falls from the second holding part 50 onto the mounting table 60.

[0045] (Lower Stage Sensor) Lower stage sensor 14 is an example of a second sensor, and detects polycrystalline silicon S that falls from discharge end 31, through first holding unit 40, and into second holding unit 50. The detection result of lower stage sensor 14 is output to control unit 20. Lower stage sensor 14 is disposed below upper stage sensor 13. The detection range of lower stage sensor 14 is desirably the portion of the horizontal plane located between support unit 41 a and support unit 51 a that overlaps with support unit 51 a in a state where holding space 52 is formed in the vertical direction.

[0046] The lower sensor 14 may be the same sensor as the upper sensor 13. While it is desirable to provide one lower sensor 14 as shown in Figures 1 and 4, a plurality of lower sensors 14 may be provided.

[0047] (Placement Table) The placement table 60 supplies the polycrystalline silicon S one by one from the first position P1 to the second position P2. The placement table 60 is movable between the first position P1 and the second position P2. The first position P1 is a position where the polycrystalline silicon S that falls downward from the second holding unit 50 can be placed. The second position P2 is a position away from the first position P1, and is, for example, a position where the polycrystalline silicon S is supplied. Furthermore, the second position P2 is, for example, a position where the above-mentioned imaging unit can image the polycrystalline silicon S.

[0048] The mounting table 60 is driven under the control of the control unit 20. The mounting table 60 places the polycrystalline silicon S that has dropped from the second holder 50 at the first position P1, and supplies the polycrystalline silicon S to the second position P2. At the second position P2, the imaging unit described above completes imaging of the polycrystalline silicon S, and the polycrystalline silicon S may be removed from the mounting table 60. Once the polycrystalline silicon S has been removed, the mounting table 60 returns from the second position P2 to the first position P1.

[0049] When the mounting table 60 is located at the first position P1, the first holding unit 40 and the second holding unit 50 are disposed above the mounting table 60. This allows the first holding unit 40 and the second holding unit 50 to temporarily hold the polycrystalline silicon S.

[0050] The transport device 1 may include only the first holding unit 40 out of the first holding unit 40 and the second holding unit 50, and may include only the upper stage sensor 13 out of the upper stage sensor 13 and the lower stage sensor 14. In this case, when the first holding unit 40 releases its hold on the polycrystalline silicon S, the polycrystalline silicon S falls from the first holding unit 40 onto the mounting table 60.

[0051] (Fourth Sensor) The fourth sensor 15 detects whether the mounting table 60 is located at the first position P1. The detection result of the fourth sensor 15 is output to the control unit 20. The fourth sensor 15 may be the same sensor as the laser sensor 12a.

[0052] (Operation flow of the transfer unit) Fig. 5 is a flow diagram showing an example of an operation of supplying polycrystalline silicon S to the transfer unit 30 included in the transfer device 1 shown in Fig. 1. Fig. 6 is a flow diagram showing an example of an operation of the transfer unit 30 included in the transfer device 1 shown in Fig. 1. The operation flow of the transfer unit 30 will be described with reference to Figs. 5 and 6.

[0053] 5, first, the control unit 20 starts supplying polycrystalline silicon S to the transport unit 30 using a supply unit (not shown) (S1). Then, the control unit 20 determines whether or not polycrystalline silicon S is detected by the third sensor 11 (S2). If polycrystalline silicon S is detected by the third sensor 11 (YES in S2), the control unit 20 stops supplying polycrystalline silicon S to the transport unit 30 by the supply unit (S3).

[0054] After stopping the supply of polycrystalline silicon S, the control unit 20 determines whether or not the detection of polycrystalline silicon S by the third sensor 11 has been released (S4). If the detection of polycrystalline silicon S by the third sensor 11 has been released (YES in S4), the control unit 20 proceeds to the processing of step S1 and resumes the supply of polycrystalline silicon S to the transport unit 30. If the detection of polycrystalline silicon S by the third sensor 11 has not been released (NO in S4), the control unit 20 continues to stop the supply of polycrystalline silicon S to the transport unit 30 until the detection of polycrystalline silicon S by the third sensor 11 has been released.

[0055] On the other hand, if polycrystalline silicon S is not detected by the third sensor 11 (NO in S2), the control unit 20 continues to supply polycrystalline silicon S to the conveying unit 30 until polycrystalline silicon S is detected by the third sensor 11.

[0056] In step S1, the control unit 20 starts supplying the polycrystalline silicon S to the transport unit 30, and then drives the transport unit 30 to transport the polycrystalline silicon S toward the discharge end 31 (S11), as shown in Fig. 6. Step S11 is an example of a transport step and a control step.

[0057] After driving the transport unit 30, the control unit 20 determines whether or not the polycrystalline silicon S has been detected by the first sensor 12 (S12). Specifically, the control unit 20 determines whether or not the polycrystalline silicon S has been detected by at least one of the laser sensors 12a to 12c. Step S12 is an example of a detection step.

[0058] When polycrystalline silicon S is detected by the first sensor 12 (YES in S12), the control unit 20 temporarily stops driving the transport unit 30 (S13). Therefore, when polycrystalline silicon S is transported following polycrystalline silicon S that has been unloaded to the outside of the transport unit 30, the transport of the subsequent polycrystalline silicon S is temporarily stopped when the first sensor 12 detects the subsequent polycrystalline silicon S. Step S13 is an example of a control process.

[0059] Then, when the transport of the polycrystalline silicon S is resumed in step S15 described below, the polycrystalline silicon S is unloaded to the outside of the transport unit 30. Therefore, the transport unit 30 can unload the polycrystalline silicon S one by one from the unloading end 31 based on the detection result of the polycrystalline silicon S by the first sensor 12. If the first sensor 12 has not detected the polycrystalline silicon S (NO in S12), the control unit 20 drives the transport unit 30 until the first sensor 12 detects the polycrystalline silicon S.

[0060] After temporarily stopping the transport unit 30 in step S13, the control unit 20 determines whether the polycrystalline silicon S is being held by the first holding unit 40 (S14). If the first holding unit 40 has not released the polycrystalline silicon S after the polycrystalline silicon S is detected by the upper sensor 13, the control unit 20 determines that the polycrystalline silicon S is being held by the first holding unit 40.

[0061] Furthermore, if the upper sensor 13 does not detect polycrystalline silicon S after the control unit 20 has caused the first holding unit 40 to release the polycrystalline silicon S, the control unit 20 determines that polycrystalline silicon S is not being held by the first holding unit 40. If the control unit 20 determines that polycrystalline silicon S is not being held by the first holding unit 40 (NO in S14), it resumes driving the transport unit 30 to unload the polycrystalline silicon S from the unloading end 31 (S15). Step S15 is an example of a transport process and a control process.

[0062] When the control unit 20 determines that the polycrystalline silicon S is being held by the first holding unit 40 (YES in S14), the control unit 20 maintains the stopped state of the conveying unit 30. After restarting the driving of the conveying unit 30, the control unit 20 determines whether the polycrystalline silicon S has been detected by the upper sensor 13 (S16).

[0063] Consider a case where it is determined that polycrystalline silicon S has been detected by the upper sensor 13 (YES in S16). In this case, the control unit 20 determines whether or not the polycrystalline silicon S transported following the polycrystalline silicon S unloaded from the unloading end 31 has been detected by the first sensor 12 (S17). When the control unit 20 determines that the next polycrystalline silicon S has been detected by the first sensor 12 (YES in S17), the control unit 20 proceeds to the processing of step S13.

[0064] When the upper sensor 13 does not detect polycrystalline silicon S (NO in S16), the control unit 20 drives the transport unit 30 until polycrystalline silicon S is detected by the upper sensor 13. When the control unit 20 determines that the next polycrystalline silicon S has not been detected by the first sensor 12 (NO in S17), the control unit 20 drives the transport unit 30 until the next polycrystalline silicon S is detected by the first sensor 12.

[0065] As described above, by using the first sensor 12 that detects the polycrystalline silicon S from multiple directions above the transport unit 30, it is possible to accurately detect amorphous polycrystalline silicon S with the first sensor 12. Therefore, the control unit 20 controls the driving of the transport unit 30 based on the detection result of the polycrystalline silicon S by the first sensor 12, so that the polycrystalline silicon S to be transported can be reliably transported outside the transport unit 30.

[0066] Furthermore, the control unit 20 controls the driving of the transport unit 30 based on the detection of polycrystalline silicon S by at least one of the plurality of laser sensors 12 a to 12 c. This allows the transport device 1 to reliably transport the polycrystalline silicon S to the outside of the transport unit 30.

[0067] (Operational Flow of First Holding Unit) Fig. 7 is a flow chart showing an example of the operation of the first holding unit 40 included in the transport device 1 shown in Fig. 1. If the answer is YES in step S16 shown in Fig. 6, the control unit 20 determines whether or not the polycrystalline silicon S is being held by the second holding unit 50 (S21). If the hold of the polycrystalline silicon S by the second holding unit 50 has not been released after the polycrystalline silicon S is detected by the lower sensor 14, the control unit 20 determines that the polycrystalline silicon S is being held by the second holding unit 50.

[0068] In addition, if the polycrystalline silicon S is not detected by the lower sensor 14 after the control unit 20 has caused the second holding unit 50 to release its holding of the polycrystalline silicon S, the control unit 20 determines that the polycrystalline silicon S is not being held by the second holding unit 50.

[0069] When the control unit 20 determines that the polycrystalline silicon S is not being held by the second holding unit 50 (NO in S21), the control unit 20 causes the first holding unit 40 to release the polycrystalline silicon S (S22). As a result, the polycrystalline silicon S falls from the first holding unit 40 to the second holding unit 50.

[0070] After causing the first holding unit 40 to release the polycrystalline silicon S, the control unit 20 determines whether or not the polycrystalline silicon S has been detected by the lower sensor 14 (S23). When the control unit 20 determines that the polycrystalline silicon S has been detected by the lower sensor 14 (YES in S23), the control unit 20 closes the first holding unit 40 (S24). When the first holding unit 40 is closed, the lower end of the support portion 41a is in contact with the wall portion 70.

[0071] On the other hand, when the control unit 20 determines that the polycrystalline silicon S is being held by the second holding unit 50 (YES in S21), the control unit 20 waits until the second holding unit 50 releases the polycrystalline silicon S from being held.

[0072] When the control unit 20 determines that polycrystalline silicon S has not been detected by the lower sensor 14 (NO in S23), the first holding unit 40 maintains the open state until polycrystalline silicon S is detected by the lower sensor 14. The open state of the first holding unit 40 is a state in which the support portion 41 a and the wall portion 70 are separated. Note that, when the control unit 20 detects polycrystalline silicon S by the first sensor 12 while the control unit 20 is executing the process shown in FIG. 7, the control unit 20 executes the process from step S13 onwards shown in FIG.

[0073] (Operation Flow of Second Holding Unit) FIG. 8 is a flow diagram showing an example of the operation of the second holding unit 50 included in the transport device 1 shown in FIG. 1 . After step S24 shown in FIG. 7 , the control unit 20 determines whether the fourth sensor 15 detects that the mounting table 60 is at the first position P1 (S31). When the control unit 20 determines that the mounting table 60 is detected by the fourth sensor 15 (YES in S31), it causes the second holding unit 50 to release its hold on the polycrystalline silicon S (S32). This causes the polycrystalline silicon S to fall from the second holding unit 50 onto the mounting table 60. Also, in step S32, the second holding unit 50 is in an open state. In this state, the support portion 51 a and the wall portion 70 are separated from each other.

[0074] Therefore, based on the detection results of the polycrystalline silicon S by the upper stage sensor 13 and the lower stage sensor 14, the control unit 20 places the polycrystalline silicon S on the mounting table 60 by causing the first holding unit 40 and the second holding unit 50 to release their hold on the polycrystalline silicon S.

[0075] After causing the second holding unit 50 to release the polycrystalline silicon S, the control unit 20 determines whether the fourth sensor 15 has detected that the mounting table 60 has been retracted (S33). In step S33, if the mounting table 60 is not at the first position P1, the fourth sensor 15 detects that the mounting table 60 has been retracted. At this time, the control unit 20 determines that the mounting table 60 has moved from the first position P1 to the second position P2. The control unit 20 also determines that there is no inventory of polycrystalline silicon S. This inventory is the inventory of polycrystalline silicon S to be supplied to the transport unit 30.

[0076] Furthermore, when the mounting table 60 is present at the first position P1, the fourth sensor 15 detects that the mounting table 60 has not been retracted. At this time, the control unit 20 determines that the mounting table 60 is waiting at the first position P1.

[0077] If the fourth sensor 15 detects that the mounting table 60 has been retracted (YES in S33), the control unit 20 closes the second holding unit 50 (S34). When the second holding unit 50 is closed, the lower end of the support portion 51a is in contact with the wall portion 70. On the other hand, when the fourth sensor 15 detects that the mounting table 60 has not been retracted (NO in S33), the control unit 20 keeps the second holding unit 50 open.

[0078] On the other hand, when the control unit 20 determines that the mounting table 60 has not been detected by the fourth sensor 15 (NO in S31), the control unit 20 waits until the mounting table 60 is detected by the fourth sensor 15.

[0079] (Operational Flow of Mounting Table) Fig. 9 is a flow diagram showing an example of the operation of the mounting table 60 included in the transfer device 1 shown in Fig. 1. After step S32 shown in Fig. 8, the control unit 20 moves the mounting table 60 on which the polycrystalline silicon S is placed from the first position P1 to the second position P2 (S41).

[0080] After the control unit 20 moves the mounting table 60 from the first position P1 to the second position P2, the polycrystalline silicon S is photographed by the above-mentioned photographing unit, and the polycrystalline silicon S is removed from the mounting table 60. Then, the control unit 20 moves the mounting table 60 from the second position P2 to the first position P1 (S42). While executing the process of step S41 or S42, the control unit 20 continues the process of the steps shown in FIGS. 5 to 7 and the process of step S31 shown in FIG. 8.

[0081] As described above, the transport device 1 is capable of temporarily holding the polycrystalline silicon S by including the first holding unit 40 and the second holding unit 50 that can hold the polycrystalline silicon S. Furthermore, the control unit 20 causes the first holding unit 40 and the second holding unit 50 to release the hold of the polycrystalline silicon S based on the detection results of the polycrystalline silicon S by the upper stage sensor 13 and the lower stage sensor 14.

[0082] As a result, the control unit 20 recognizes from the detection results of the upper stage sensor 13 and the lower stage sensor 14 that the polycrystalline silicon S is being held by at least one of the first holding unit 40 and the second holding unit 50, and then drops the polycrystalline silicon S from the second holding unit 50. The control unit 20 can then place the polycrystalline silicon S on the mounting table 60.

[0083] Furthermore, when the mounting table 60 returns from the second position P2 to the first position P1, the polycrystalline silicon S is released from the first holding unit 40 and the second holding unit 50, allowing the polycrystalline silicon S to be immediately placed on the mounting table 60 from the first holding unit 40 and the second holding unit 50. Therefore, the polycrystalline silicon S can be smoothly supplied from the first position P1 to the second position P2.

[0084] [Summary] The polycrystalline silicon transport device according to aspect 1 of the present invention comprises a transport section having an unloading end from which the polycrystalline silicon is unloaded and which transports the polycrystalline silicon and unloads the polycrystalline silicon from the unloading end to the outside, a first sensor located above the transport section which detects the polycrystalline silicon from multiple directions, and a control section which controls the driving of the transport section based on the detection results of the polycrystalline silicon by the first sensor.

[0085] By using the first sensor that detects the polycrystalline silicon from multiple directions above the transport unit, amorphous polycrystalline silicon can be detected with high accuracy by the first sensor. Therefore, the control unit controls the drive of the transport unit based on the detection result of the polycrystalline silicon by the first sensor, so that the polycrystalline silicon to be transported can be reliably transported outside the transport unit.

[0086] In a polycrystalline silicon conveying device according to aspect 2 of the present invention, in aspect 1, the first sensor may be a plurality of laser sensors arranged to detect the polycrystalline silicon from different directions, and the control unit may control the driving of the conveying unit based on the detection of the polycrystalline silicon by at least one laser sensor of the plurality of laser sensors.

[0087] A plurality of laser sensors are provided to detect the polycrystalline silicon from different directions. This allows the use of laser sensors that are less expensive than image sensors, etc., thereby reducing the manufacturing cost of the polycrystalline silicon transport device. Furthermore, the control unit controls the drive of the transport unit based on the detection of polycrystalline silicon by at least one of the plurality of laser sensors. This allows the polycrystalline silicon transport device to reliably transport the polycrystalline silicon to the outside of the transport unit.

[0088] In the polycrystalline silicon transport device according to Aspect 3 of the present invention, in Aspect 1 or 2, the transport unit may include a vibrating feeder that transports the polycrystalline silicon by vibrating.

[0089] By using a vibrating feeder as a conveying unit for conveying polycrystalline silicon, it is easy to control the conveyance of polycrystalline silicon to the outside of the conveying unit. In addition, amorphous polycrystalline silicon vibrated by the vibrating feeder can be detected with high accuracy by multiple laser sensors. Therefore, it is possible to easily control the conveyance of polycrystalline silicon to the outside of the conveying unit and accurately detect amorphous polycrystalline silicon at the same time.

[0090] In the polycrystalline silicon transport device according to aspect 4 of the present invention, in any one of aspects 1 to 3, the control unit may temporarily suspend operation of the transport unit when the polycrystalline silicon is detected by the first sensor.

[0091] When polycrystalline silicon is transported following polycrystalline silicon that has been transported to the outside of the transport unit, the transport of the polycrystalline silicon is temporarily stopped when the first sensor detects the subsequent polycrystalline silicon. When the transport of the polycrystalline silicon is resumed, the polycrystalline silicon is transported to the outside of the transport unit. Therefore, the transport unit can transport the polycrystalline silicon one by one from the transport end to the outside based on the detection result of the polycrystalline silicon by the first sensor.

[0092] In the polycrystalline silicon transport device according to Aspect 5 of the present invention, in any one of Aspects 1 to 4, the first sensor may detect the polycrystalline silicon in the vicinity of the discharge end from a plurality of directions.

[0093] The first sensor detects polycrystalline silicon near the discharge end from which the polycrystalline silicon is discharged, allowing the control unit to accurately recognize the polycrystalline silicon immediately before it is discharged to the outside of the transport unit. Therefore, since the polycrystalline silicon detected by the first sensor is immediately discharged to the outside of the transport unit, the first sensor can detect the next polycrystalline silicon to be transported after the polycrystalline silicon has been discharged to the outside of the transport unit. Therefore, the control unit can control the drive of the transport unit to smoothly transport the polycrystalline silicon based on the detection result of the polycrystalline silicon by the first sensor.

[0094] A polycrystalline silicon transport device according to a sixth aspect of the present invention is, in any one of the first to fifth aspects, provided with a holding section capable of holding the polycrystalline silicon discharged from the discharge end, and a second sensor that detects the polycrystalline silicon falling from the discharge end onto the holding section, and the control section may, based on the detection result of the polycrystalline silicon by the second sensor, cause the holding section to release its hold on the polycrystalline silicon, thereby placing the polycrystalline silicon on a mounting table that is movable between a first position where the polycrystalline silicon falling downward from the holding section can be placed, and a second position away from the first position.

[0095] The polycrystalline silicon transport device includes a holding unit capable of holding polycrystalline silicon, thereby enabling the polycrystalline silicon to be temporarily held. Furthermore, the control unit causes the holding unit to release the polycrystalline silicon based on the detection result of the polycrystalline silicon by the second sensor. Thus, the control unit recognizes from the detection result of the second sensor that the polycrystalline silicon is being held by the holding unit, and then drops the polycrystalline silicon from the holding unit and places the polycrystalline silicon on the mounting table.

[0096] Furthermore, when the mounting table returns from the second position to the first position, the polycrystalline silicon is released from the holding unit, allowing the polycrystalline silicon to be immediately placed on the mounting table from the holding unit, thereby enabling the polycrystalline silicon to be smoothly supplied from the first position to the second position.

[0097] A method for transporting polycrystalline silicon according to aspect 7 of the present invention includes a transport step of transporting the polycrystalline silicon using a transport unit having an outlet end from which the polycrystalline silicon is transported, and transporting the polycrystalline silicon to the outside from the outlet end, a detection step of detecting the polycrystalline silicon from multiple directions on the transport unit, and a control step of controlling the drive of the transport unit based on the detection results of the polycrystalline silicon by the detection step.

[0098] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Configurations obtained by appropriately combining the technical means disclosed in the embodiments are also included in the technical scope of the present invention.

[0099] REFERENCE SIGNS LIST 1 Conveying device 12 First sensor 13 Upper stage sensor (second sensor) 14 Lower stage sensor (second sensor) 20 Control unit 30 Conveying unit 31 Unloading end 40 First holding unit (holding unit) 50 Second holding unit (holding unit) 60 Placement table P1 First position P2 Second position S Polycrystalline silicon

Claims

1. A polycrystalline silicon transport device comprising: a transport unit having an unloading end from which polycrystalline silicon is unloaded and which transports the polycrystalline silicon and unloads it from the unloading end to the outside; a first sensor located above the transport unit which detects the polycrystalline silicon from multiple directions; and a control unit which controls the operation of the transport unit based on the detection results of the polycrystalline silicon by the first sensor.

2. The polycrystalline silicon transport device described in claim 1, characterized in that the first sensor is a plurality of laser sensors arranged to detect the polycrystalline silicon from different directions, and the control unit controls the operation of the transport unit based on the detection of the polycrystalline silicon by at least one of the plurality of laser sensors.

3. The polycrystalline silicon transport device according to claim 2, wherein the transport section includes a vibrating feeder that transports the polycrystalline silicon by vibrating.

4. A polycrystalline silicon transport device as described in any one of claims 1 to 3, characterized in that the control unit temporarily halts the operation of the transport unit when the polycrystalline silicon is detected by the first sensor.

5. A polycrystalline silicon transport device according to any one of claims 1 to 3, characterized in that the first sensor detects the polycrystalline silicon in a plurality of directions in the vicinity of the discharge end.

6. A polycrystalline silicon transport device as described in any one of claims 1 to 3, comprising: a holding section capable of holding the polycrystalline silicon discharged from the discharge end; and a second sensor that detects the polycrystalline silicon falling from the discharge end onto the holding section, wherein the control section, based on the detection result of the polycrystalline silicon by the second sensor, causes the holding section to release its hold on the polycrystalline silicon, thereby placing the polycrystalline silicon on a mounting table that is movable between a first position where the polycrystalline silicon falling downward from the holding section can be placed and a second position separated from the first position.

7. A method for transporting polycrystalline silicon, comprising: a transport step of transporting polycrystalline silicon by a transport part having an outlet end from which the polycrystalline silicon is transported, and transporting the polycrystalline silicon to the outside from the outlet end; a detection step of detecting the polycrystalline silicon from a plurality of directions on the transport part; and a control step of controlling the operation of the transport part based on the detection results of the polycrystalline silicon by the detection step.

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