JP2020174085A - Substrate transport device and substrate transport method - Google Patents

Abstract

To transport a substrate to a delivery position where transport robot hands access and receive the substrate and the substrate is positioned with high accuracy.SOLUTION: A substrate transport device includes a roller conveyor in which a plurality of transport rollers in which a plurality of roller members is provided to be separated from each other in a first horizontal direction on a rotary shaft extending in the first horizontal direction is disposed parallel to each other in a second horizontal direction orthogonal to the first horizontal direction, a plurality of drive motors, connected to an end of the rotary shaft for each of the transport rollers, for rotating the transport rollers around an axis of the rotary shaft, and a transport control unit for positioning a substrate at a delivery position by stopping the drive motors in synchronization after decelerating a speed of the substrate to be transported toward the delivery position to a constant speed with the same deceleration by the roller conveyer by controlling the driving motors in synchronization.SELECTED DRAWING: Figure 1

Description

The present invention relates to a substrate transfer technique for transporting and positioning a substrate using a roller conveyor at a delivery position where the hand of the transfer robot accesses and receives the substrate. The substrates include FPD glass substrates such as liquid crystal display devices and organic EL display devices, semiconductor wafers, photomask glass substrates, color filter substrates, recording disk substrates, solar cell substrates, and electronic paper substrates. Such as substrates for precision electronic devices, semiconductor packages, etc. are included.

As an example of a substrate processing apparatus that performs a predetermined treatment on a substrate, for example, there is an apparatus described in Patent Document 1. This device is a slit coater that applies a coating liquid to the upper surface of a substrate conveyed in a horizontal posture, and dispenses the coated substrate to an external device. This dispensing operation is performed by a roller conveyor provided in the substrate processing apparatus and, for example, a transfer robot described in Patent Document 2. That is, the roller conveyor conveys the substrate to the transfer position of the substrate with the transfer robot and positions it. After that, the hand of the transfer robot accesses the delivery position, receives the board, and transfers it to the next board processing device.

Japanese Unexamined Patent Publication No. 2018-187597 Japanese Unexamined Patent Publication No. 2013-103331

Patent Document 1 does not specifically describe a rotary drive mechanism that rotationally drives a plurality of conveyor rollers constituting the roller conveyor, but the roller conveyor is rotationally driven by combining a single drive motor and a drive transmission mechanism. ing. However, in recent years, the following problems have arisen with the increase in size of the substrate.

It is necessary to increase the number of transport rollers constituting the roller conveyor and the number of parts of the drive transmission mechanism as the substrate becomes larger. Further, in order to convey the enlarged substrate, the hand of the transfer robot has to be increased in size, and the roller diameter of the roller member is increased accordingly to the finger roller conveyor extending from the hand. An entry space must be secured. As a result, the inertial force (inertia) generated when the roller conveyor is rotationally driven increases cumulatively, making it difficult to improve the positioning accuracy at the delivery position. Further, in the drive transmission mechanism, a plurality of gears are often used for drive transmission, and backlash or the like occurs in gear connection, which lowers the positioning accuracy.

The present invention has been made in view of the above problems, and provides a substrate transfer device and a substrate transfer method capable of transporting a substrate to a transfer position where the hand of a transfer robot accesses and receives the substrate and positioning the substrate with high accuracy. The purpose is.

One aspect of the present invention is a substrate transfer device for transporting and positioning a substrate to a delivery position where the hand of the transfer robot accesses and receives the substrate, and a plurality of rollers are provided on a rotation axis extending in the first horizontal direction. A plurality of transport rollers in which members are provided so as to be separated from each other in the first horizontal direction, a roller conveyor arranged parallel to each other in the second horizontal direction orthogonal to the first horizontal direction, and an end of a rotation shaft for each transport roller. The speed of the substrate transported toward the delivery position by the roller conveyor is controlled by synchronously controlling the plurality of drive motors and the plurality of drive motors that are connected to and rotate the transfer roller around the axis of the rotation shaft. It is characterized by including a transport control unit that simultaneously stops a plurality of drive motors and positions the substrate at the delivery position after decelerating to a constant speed at the same deceleration.

Further, in another aspect of the present invention, a plurality of transport rollers provided with a plurality of roller members separated from each other in the first horizontal direction on a rotation axis extending in the first horizontal direction are orthogonal to the first horizontal direction. A substrate transfer method in which the substrates are transported to the transfer position by a roller conveyor arranged parallel to each other in the second horizontal direction and positioned so as to be delivered to the transfer robot. The drive is connected to the end of each rotating shaft. A process in which the motors are driven synchronously to transport the substrate toward the delivery position by multiple transfer rollers and then the speed of the substrate is reduced to a constant speed at the same deceleration, and when the substrate is conveyed at a constant speed. It is characterized by including a step of stopping a plurality of drive motors at the same time and positioning the substrate at the delivery position.

In the invention configured in this way, the roller conveyor is composed of a plurality of transfer rollers, and a drive motor is connected to the end of the rotating shaft of each transfer roller. Then, in order to position the substrate conveyed by the roller conveyor at the delivery position, a plurality of drive motors are synchronously controlled as follows. That is, after the speed of the substrate transported by the roller conveyor, that is, the transport speed is decelerated to a constant speed at the same deceleration, the plurality of drive motors are stopped at the same time. As a result, the substrate is accurately positioned at the delivery position. The "deceleration" is the rate of decrease in the speed of the substrate per unit time, and means a negative acceleration (rate of change in the speed of the substrate per unit time).

As described above, since the drive motors are connected to each of the transfer rollers constituting the roller conveyor and the drive motors are rotationally driven in synchronization with each other, the inertial force (inertia) generated in each transfer roller is small. Further, a drive motor is connected to the rotating shaft of each transport roller. For this reason, the power transmission path is shorter than that of the conventional device in which a plurality of transfer rollers are driven by a smaller number of drive motors than the transfer rollers, and the plurality of transfer rollers are controlled synchronously, so that the positioning accuracy is improved. Can be made to.

It is a figure which shows the substrate processing apparatus which is equipped with the 1st Embodiment of the substrate transfer apparatus which concerns on this invention. It is a partial perspective view which shows the partial structure of the output conveyor which constitutes a substrate transfer apparatus. It is a figure which shows an example of the transport mode of a substrate by an output conveyor. It is a figure which shows an example of the substrate transporting mode by an output conveyor in the substrate processing apparatus equipped with the 2nd Embodiment of the substrate transporting apparatus which concerns on this invention. It is a partial perspective view which shows the partial structure of the output conveyor in the substrate processing apparatus equipped with the 3rd Embodiment of the substrate transfer apparatus which concerns on this invention.

FIG. 1 is a diagram showing a substrate processing device equipped with the first embodiment of the substrate transfer device according to the present invention, and FIG. 2 is a partial perspective view showing a partial configuration of an output conveyor constituting the board transfer device. The substrate processing device 1 has the same configuration as the device described in Patent Document 1 except for the configuration and operation of the output conveyor and the rotary drive mechanism that rotationally drives the output conveyor. That is, in the substrate processing apparatus 1, a coating liquid is supplied from a nozzle (not shown) to the upper surface Bf of the substrate B which is levitated and conveyed in a horizontal posture, whereby the coating process on the substrate B is performed. Further, the substrate B that has undergone the coating process is transferred to the output conveyor 3 by the output transfer unit 2. The output transfer unit 2 includes a roller conveyor 21 and a rotation / elevation drive mechanism 22 having a function of rotationally driving the roller conveyor 21 and a function of raising and lowering the roller conveyor 21. The roller conveyor 21 rotates by operating the rotation / elevating drive mechanism 22 in response to a command from the control unit 9 that controls the entire device. As a result, a propulsive force in the X direction is applied to the substrate B, and the substrate B is conveyed toward the output conveyor 3. Further, as the roller conveyor 21 moves up and down, the vertical position of the substrate B is changed, and the substrate B can be smoothly transferred to the output conveyor 3.

The output conveyor 3 is configured as described in detail later, conveys the substrate B in the X direction, and positions it at the delivery position P with the transfer robot 200.

The transfer robot 200 has hands 210 and 220 arranged in two upper and lower stages like the robot described in Patent Document 2, for example. Then, the robot control unit 230 operates the elevating mechanism (not shown) and the rotating mechanism (not shown) equipped on the robot body 240, so that one of the hands 210 and 220 accesses the delivery position P and receives the substrate B. , Send to another board processing device. In FIG. 1, the substrate B is carried out from the substrate processing device 1 by the so-called double-hand type transfer robot 200, but a single-hand type transfer robot may be used.

Next, the configurations of the output conveyor 3 and the rotary drive mechanism 4, which are the components of the substrate transport device according to the present invention, will be described. The output conveyor 3 is formed by arranging a plurality of (9 in this embodiment) transfer rollers 31 in parallel with each other in a state of being separated from each other in the X direction. Each transport roller 31 has a rotating shaft 311 extending in the Y direction orthogonal to the X direction, and a plurality of roller members 312 provided apart from each other in the Y direction with respect to the rotating shaft 311. Each rotation shaft 311 is pivotally supported in the X direction at a constant pitch Px in a state of being rotatable around an axis axis AX (FIG. 2) extending in the Y direction. In the present embodiment, in order to stably transport the thin and large substrate B by rollers while supporting it from below, and to avoid interference with the hands 210 and 220 in delivering the substrate B to the transfer robot 200. A roller member 312 having a relatively large outer diameter is used, and the pitch Px of the rotating shaft 311 of the transport roller 31 is set shorter than the outer diameter of the roller member 312, that is, the roller diameter.

In order to enable such a setting, as shown in FIG. 2, the plurality of roller members 312 provided on one transfer roller 31 in the two transfer rollers 31 adjacent to each other are provided on the other transfer roller 31. A plurality of roller members 312 are provided so as to be offset in the Y direction. Therefore, it is possible to transport the large substrate B while supporting a large number of portions of the lower surface Bb of the large substrate B from below, and it is possible to stably transport the large substrate B. However, in the output conveyor 3, it is necessary to deliver the substrate B to the hand 210 (or hand 220) of the transfer robot 200 at the delivery position P, and the roller member 312 and the finger 211 of the hand 210 (or the finger 221 of the hand 220) It is necessary to prevent interference.

Therefore, in the present embodiment, as shown in FIG. 2, the deviation amount ΔY of the roller member 312 in the Y direction in the two adjacent transport rollers 31 is half (more preferably 1/4) of the pitch Py of the roller member 312. Is set to a value smaller than. Therefore, the space SP for inserting the finger 211 (or the finger 221) is formed sufficiently wide, and the substrate B can be smoothly delivered. In other words, the roller member 312 is the finger 211 (or finger) of the hand 210 (or hand 220) that enters between the substrate B supported by the plurality of roller members 312 at the delivery position P and the plurality of rotating shafts 311. It is provided at a position avoiding 221). Further, by providing such a space SP, it becomes easy to arrange the deceleration start sensor S1 for detecting the deceleration start position Pds of the substrate B and the stop sensor S2 for stopping the substrate B at the delivery position P. ..

Of these sensors, the stop sensor S2 outputs a stop signal to the control unit 9 when the substrate B is located at the delivery position P. Therefore, the arrangement position of the stop sensor S2 is uniquely determined corresponding to the delivery position P. On the other hand, the deceleration start sensor S1 is arranged on the upstream side of the stop sensor S2 in the X direction, and outputs a deceleration start signal to the control unit 9 when the substrate B is located at the deceleration start position Pds. Therefore, the arrangement position of the deceleration start sensor S1 is strongly influenced by the size of the substrate B, particularly the size in the X direction. Therefore, in the present embodiment, the deceleration start sensor S1 is configured to be movable at different positions in the X direction, and the deceleration start sensor S1 is arranged at a position corresponding to the type of the substrate B. As the deceleration start sensor S1 and the stop sensor S2, sensors such as a reflection type and a capacitance type can be preferably used.

The rotary drive mechanism 4 for rotationally driving the output conveyor 3 configured in this way has a plurality of (nine in this embodiment) motors 41 with brakes. That is, the rotating shaft of the motor 41 is connected to the (+ Y) side end of each rotating shaft 311 via the coupling 42. Further, a motor driver 43 is electrically connected to each motor 41, and the motor 41 is accelerated / decelerated based on preset data 921 given from the control unit 9. Further, as will be described later, the power supply to the motor 41 is cut off based on the stop signal from the stop sensor, and the rotation of the rotation shaft of the motor 41 can be stopped instantly by the operation of the brake. If the substrate B can be stopped instantaneously only by shutting off the power supply, a motor without a brake may be used.

The control unit 9 includes an arithmetic processing unit 91, a storage unit 92, and the like in order to control each unit of the substrate processing device 1. In particular, in the present embodiment, a plurality of preset data 921 that define the acceleration / deceleration pattern of the motor 41 are stored in advance in the storage unit 92. Then, the arithmetic processing unit 91 has an arithmetic function such as a CPU (Central Processing Unit), and among the preset data 921 stored in the storage unit 92, preset data 921 suitable for the type of the substrate B is simultaneously input. It is given to all motor drivers 43 to synchronously control all motors 41. As a result, all the transport rollers 31 rotate in the same acceleration / deceleration pattern to transport the substrate B and position it at the delivery position P. In this way, the arithmetic processing unit 91 functions as the transport control unit 911.

FIG. 3 is a diagram showing an example of a substrate transport mode by an output conveyor. In the figure, the horizontal axis is time, and the vertical axis is the rotation speed (rotation speed per unit time) of each motor 41. At the timing T0 before the substrate B is transferred to the output conveyor 3 at a predetermined transfer speed V11 by the roller conveyor 21 of the output transfer unit 2, the transfer control unit 911 starts accelerating drive of all the motors 41 and is a roller conveyor. At the time when the substrate B is transferred from the 211, all the motors 41 rotate steadily at the rotation speed V1 and can convey the substrate B at the same speed as the transfer speed V11 of the substrate B from the roller conveyor 21. Therefore, the substrate B can be stably transferred from the roller conveyor 21 to the output conveyor 3.

The substrate B transferred from the roller conveyor 21 is conveyed in the X direction by the output conveyor 3 at a constant transfer speed V11. Then, as shown in the upper right drawing in FIG. 3, when the end portion of the substrate B on the (+ X) direction side reaches the deceleration start position Pds, the deceleration start signal S1 transmits a deceleration start signal to the control unit 9. At the timing T1 when the deceleration start signal is received, the transport control unit 911 starts decelerating all the motors 41. In this embodiment, the deceleration α (that is, negative acceleration) expressed by the following equation,
Deceleration α = (V2-V1) / (T2-T1)
The rotation speed of all the motors 41 is reduced to a speed V2 that can be stopped instantly over time (T2-T1). After that, as shown in the middle right drawing in FIG. 3, the transport control unit 911 constantly rotates all the motors 41 at a constant rotation speed V2, and transports the substrate B at a transport speed V21 capable of instantaneously stopping the substrate B. .. Then, when the end portion of the substrate B on the (+ X) direction side reaches the delivery position P, a stop signal is transmitted from the stop sensor S2 to the control unit 9. At the timing T3 when this stop signal is received, the transport control unit 911 instantly stops all the motors 41 (see the lower right drawing in FIG. 3). As a result, the substrate B is positioned at the delivery position P with high accuracy.

As described above, according to the present embodiment, the motor 41 is connected to each of the plurality of transfer rollers 31 constituting the output conveyor 3, and by controlling them in synchronization, the transfer speed of the substrate B becomes constant. After decelerating to V21 at the same deceleration, the motor 41 is stopped at the same time to position the substrate B at the delivery position P. Therefore, the inertial force generated by each transfer roller 31 is small, and the power transmission path is shorter than that of the conventional device, so that the positioning accuracy can be improved.

In the above-described embodiment, the Y direction and the X direction correspond to the "first horizontal direction" and the "second horizontal direction" of the present invention, respectively. Further, the output conveyor 3 and the motor 41 correspond to examples of the "roller conveyor" and the "drive motor" of the present invention, respectively. The substrate transfer device according to the present invention is configured by the output conveyor 3, the motor 41, and the transfer control unit 911 that drives and controls the motor 41.

The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, the deceleration of the substrate B is started by the deceleration start signal S1 as a trigger. Therefore, it is necessary for the operator to manually change the arrangement position of the deceleration start sensor S1 in the X direction according to the change in the type of the substrate B. Instead of this manual operation, for example, a deceleration reference sensor S0 is arranged on the upstream side of the stop sensor S2 in the X direction, and when a deceleration reference signal is output from the deceleration reference sensor S0 as shown in FIG. 4 (timing T0). ) May be delayed by a time ΔT to start deceleration. In this case, the deceleration delay time ΔT corresponding to the change in the type of the substrate B is stored in the storage unit 92 in advance as a recipe in which the type of the substrate B and the deceleration delay time ΔT are associated with each other. The deceleration delay time ΔT may be optimized by selecting a recipe. As a result, for any type of substrate B, the deceleration of the substrate B can always be started at an appropriate timing T1 to position the substrate B at the delivery position P with high accuracy. Further, it is not necessary to adjust the sensor arrangement position due to the change of the type of the substrate B, and the workability can be improved.

Further, the speed pattern may be changed together with the deceleration delay time ΔT or without changing the deceleration delay time ΔT. For example, as shown in the region R in FIG. 4, the speed pattern may be changed so that the deceleration at the start of deceleration is gradually increased to reach the desired deceleration α and then the deceleration α is maintained. Of course, the speed pattern may be changed so that the deceleration changes at the same time as the start of deceleration or except at the start of deceleration.

Further, as shown in FIG. 5, a rotation detection mechanism 5 may be provided for each transfer roller 31. The rotation detection mechanism 5 includes a sensor dog 51 having a protrusion 511 for detecting the position in the rotation direction, and a photo microsensor 52 for detecting the protrusion 511. The sensor dog 51 is attached to the end of the rotating shaft 311 on the (−Y) direction side, and rotates around the axis AX with the rotation of the rotating shaft 311. In each rotation detection mechanism 5, each time the photo microsensor 52 detects the protrusion 511, a rotation position signal indicating the rotation position of the transfer roller 31 is output to the control unit 9. Therefore, by referring to the rotation position signal output from each rotation detection mechanism 5, the synchronization status of the transfer roller 31 can be acquired with high accuracy, and the accuracy of synchronization control can be improved.

Further, in the above embodiment, the synchronous control of the transfer roller 31 is executed by giving the same preset data 921 to all the motor drivers 43, but the synchronous control may be performed by a method other than this. For example, when the motor 41 and the motor driver 43 whose rotation speed can be changed by the speed control signal from the control unit 9 are used, the following motor control may be performed. For example, a table having different acceleration / deceleration patterns is stored in the storage unit 92, an acceleration / deceleration pattern corresponding to the type of the substrate B or the like is selected, and a pulse signal corresponding to the acceleration / deceleration pattern is used as a speed control signal. It may be given to all motor drivers 43 at the same time to control all motors 41 in synchronization. Instead of the pulse signal, an electric signal such as a current signal, a voltage signal, or a frequency signal may be used as a speed control signal.

Further, in the above embodiment, the present invention is applied only to the output conveyor 3 of the substrate processing apparatus 1, but the present invention may also be applied to the output transfer unit 2. As a result, the substrate B can be stably conveyed even while being transferred from the output transfer unit 2 to the output conveyor 3, and the positioning accuracy to the delivery position P can be further improved. Further, the application target of the present invention is not limited to the output conveyor 3 of the substrate processing device 1, and can be applied to all the substrate transfer techniques for transferring the substrate to the transfer position with the transfer robot by the roller conveyor.

INDUSTRIAL APPLICABILITY The present invention can be applied to all board transfer techniques for transporting and positioning a substrate by using a roller conveyor at a delivery position where the hand of the transfer robot accesses and receives the substrate.

1 ... Substrate processing device 2 ... Output transfer unit 3 ... Output conveyor (roller conveyor)
4 ... Rotational drive mechanism 41 ... (Drive) motor 31 ... Transfer roller 92 ... Storage unit 200 ... Transfer robot 210, 220 ... Hand 211, 221 ... (Hand) finger 311 ... Rotation shaft 312 ... Roller member 911 ... Transfer control unit 921 ... Preset data AX ... (Rotating axis) Axial center B ... Board Bb ... (Board) Bottom surface Bf ... (Board) top surface P ... Delivery position Px ... Pitch (spacing of rotation axes in the X direction)
Pds ... Deceleration start position S0 ... Deceleration reference sensor S1 ... Deceleration start sensor S2 ... Stop sensor SP ... Space T0 ... (Receive deceleration reference signal from deceleration reference sensor) Timing T1 ... (Receive deceleration start signal from deceleration start sensor) Timing T3 ... (Receives stop signal from stop sensor) Timing X ... 2nd horizontal direction Y ... 1st horizontal direction α ... Deceleration ΔT ... Deceleration delay time

Claims (8)

A board transfer device that transfers and positions the board to a delivery position where the hand of the transfer robot accesses and receives the board.
A plurality of transport rollers in which a plurality of roller members are provided apart from each other in the first horizontal direction on a rotation axis extending in the first horizontal direction are parallel to each other in a second horizontal direction orthogonal to the first horizontal direction. Roller conveyors arranged in
A plurality of drive motors that are connected to the end of the rotating shaft for each transport roller and rotate the transport roller around the axis of the rotating shaft.
By controlling the plurality of drive motors in synchronization, the speed of the substrate conveyed toward the delivery position by the roller conveyor is decelerated to a constant speed at the same deceleration, and then the plurality of drive motors are simultaneously operated. A transfer control unit that stops and positions the substrate at the delivery position,
A substrate transfer device comprising. The substrate transport device according to claim 1.
A stop sensor that outputs a stop signal when it detects that the board is located at the delivery position is provided.
When the transfer control unit receives the stop signal from the stop sensor, the transfer control unit is a substrate transfer device that simultaneously stops the plurality of drive motors. The substrate transport device according to claim 1 or 2.
A deceleration start sensor is provided which is arranged on the upstream side of the delivery position in the second horizontal direction and outputs a deceleration start signal when the substrate is detected.
The arrangement position of the deceleration start sensor can be changed in the second horizontal direction.
When the transfer control unit receives the deceleration start signal from the deceleration start sensor, the transfer control unit starts deceleration of the substrate. The substrate transport device according to claim 1 or 2.
A deceleration reference sensor that is arranged on the upstream side of the delivery position in the second horizontal direction and outputs a deceleration reference signal when the substrate is detected is provided.
The transfer control unit is a substrate transfer device that starts deceleration of the substrate with a delay of the deceleration reference sensor and a deceleration delay time corresponding to the type of the substrate. The substrate transport device according to claim 4.
A storage unit for storing a plurality of recipes in which the type of the substrate is associated with the deceleration delay time is provided.
The transfer control unit reads the recipe corresponding to the type of the substrate detected by the deceleration reference sensor from the storage unit, and determines the deceleration delay time based on the read recipe. The substrate transfer device according to any one of claims 1 to 5.
The distance between the plurality of rotating shafts in the second horizontal direction is narrower than the roller diameter of the roller member.
In the two transfer rollers adjacent to each other, a plurality of roller members provided on the other transfer roller are provided so as to be displaced in the first horizontal direction with respect to a plurality of roller members provided on one of the transfer rollers. apparatus. The substrate transport device according to claim 6.
The plurality of roller members are provided at a position where the fingers of the hand that enter between the substrate supported by the plurality of roller members and the plurality of rotating shafts are avoided at the delivery position. .. A plurality of transport rollers provided with a plurality of roller members separated from each other in the first horizontal direction on a rotation axis extending in the first horizontal direction are parallel to each other in the second horizontal direction orthogonal to the first horizontal direction. It is a substrate transfer method in which the substrates are transported to the transfer position by the arranged roller conveyors and positioned so as to be delivered to the transfer robot.
After the drive motors connected to the ends of the rotating shafts are synchronously driven to transport the substrate toward the delivery position by the plurality of transport rollers, the speed of the substrate is reduced to a constant speed. And the process of decelerating with
A step of simultaneously stopping the plurality of drive motors when the substrate is being conveyed at the constant speed to position the substrate at the delivery position.
A substrate transport method comprising.

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