Substrate transfer device and method for operating the substrate transfer device

Abstract

The present invention relates to a substrate transfer device that senses a collision of an end - effector and a method of operating the substrate transfer device. The substrate transfer device includes an end - effector on which a substrate is supported, a motor that provides power for the movement of the end - effector, a collision sensing unit that senses a collision of the end - effector, and a control unit that controls the driving of the motor in response to the collision sensing by the collision sensing unit. The collision sensing unit may include a torque measurement unit that measures a torque value of the motor, a differential value calculation unit that calculates a torque differential value between two torque measurement values measured with a time difference, and a collision determination unit that determines a collision of the end - effector based on the torque differential value.

Description

Technical Field

[0001] The present invention relates to a substrate transfer device and an operation method thereof, and more particularly, to a substrate transfer device that senses a collision of an end-effector and an operation method thereof.

Background Art

[0002] In the manufacturing processes of semiconductors and displays, in order to carry out various unit processes such as vapor deposition, etching, and cleaning, a plurality of devices suitable for each process characteristic are provided, and each of these different devices is provided with a substrate transfer device for transferring a substrate such as a wafer.

[0003] Generally, a substrate transfer device of semiconductor equipment serves to transfer a substrate from a load-lock chamber to a substrate storage member (for example, a FOUP (Front Opening Unified Pod, a sealed wafer / carrier for transfer / storage), a carrier, etc.) or from the substrate storage member to the load-lock chamber.

[0004] Such a substrate transfer device performs mechanical motion using the power provided by a motor and operates within a defined moving area. If the substrate deviates from a defined position while moving within this area, if the end-effector of the substrate transfer device is not in a defined position, or if an error occurs in the transfer program, etc., there is a possibility of a collision with an obstacle due to some cause, which may cause damage to the substrate transfer device and / or the collision object (or obstacle) or defects in the substrate.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention provides a substrate transfer device that senses a collision of an end-effector and protects the end-effector, a collision object, and / or a substrate, and an operation method of the substrate transfer device.

Means for Solving the Problems

[0007] A substrate transfer device according to an embodiment of the present invention includes an end-effector on which a substrate is supported, a motor that provides power for the movement of the end-effector, a collision sensing unit that senses a collision of the end-effector, and a control unit that controls the driving of the motor in response to the collision sensing by the collision sensing unit. The collision sensing unit may include a torque measurement unit that measures a torque value of the motor, a differential value calculation unit that calculates a torque differential value between two torque measurement values measured with a time difference, and a collision determination unit that determines a collision of the end-effector based on the torque differential value.

[0008] The collision sensing unit further includes a reference value setting unit that sets a collision determination reference value. The collision determination unit determines that there is a collision of the end-effector when the torque differential value is equal to or greater than the collision determination reference value. The control unit may stop the driving of the motor or drive the motor in the reverse direction when the collision determination unit determines a collision of the end-effector.

[0009] The collision sensing unit further includes a measurement position storage unit that records a measurement position of the torque value. The control unit may stop the driving of the motor after driving the motor to the previous measurement position.

[0010] The collision detection unit further includes a measurement value storage unit that stores the measured torque value of the motor. The torque measurement unit measures the torque value of the motor at a predetermined period, and the difference value calculation unit may calculate a torque difference value between the torque measurement value of the current period and the torque measurement value of the immediately preceding period for each of the predetermined periods.

[0011] The driving of the motor includes acceleration driving in which the torque of the motor increases, constant-speed driving in which the torque of the motor is maintained within a predetermined deviation, and deceleration driving in which the torque of the motor decreases, and may further include an acceleration time setting unit that sets the time of the acceleration driving.

[0012] The reference value setting unit may set the collision determination reference value according to the change rate of the torque value of the motor with respect to the set time of the acceleration driving.

[0013] The collision detection unit further includes a measurement period setting unit that sets the measurement period of the torque value of the motor according to the set time of the acceleration driving. The measurement period setting unit may set the measurement period of the torque value of the motor to be shorter than the set time of the acceleration driving.

[0014] The torque measurement unit may measure the torque value of the motor at least two or more times during the acceleration driving.

[0015] The torque measurement unit may measure the torque value of the motor at least at the start point of the acceleration driving.

[0016] An operation method of a substrate transfer device according to another embodiment of the present invention includes a process of providing power via a motor to move an end effector on which a substrate is supported, a process of measuring the torque value of the motor a plurality of times with a time difference, a process of calculating a torque difference value between two measured torque measurement values, and a process of determining a collision of the end effector based on the calculated torque difference value.

[0017] The operation method of the substrate transfer device further includes a process of setting a collision determination reference value, and a process of stopping the driving of the motor or driving the motor in the reverse direction when it is determined that the end effector has collided in the process of determining the collision of the end effector. In the process of determining the collision of the end effector, when the calculated torque difference value is equal to or greater than the set collision determination reference value, it may be determined that the end effector has collided.

[0018] The operation method of the substrate transfer device further includes a process of recording the measurement position of the torque value. The process of stopping the driving of the motor or driving the motor in the reverse direction may include a process of stopping the driving of the motor after driving the motor to the previous measurement position.

[0019] The operation method of the substrate transfer device further includes a process of storing the measured torque value of the motor. In the process of measuring the torque value of the motor, the torque value of the motor is measured at a predetermined period. In the process of calculating the torque difference value, the torque difference value between the torque measurement value of the current period and the torque measurement value of the immediately previous period may be calculated for each predetermined period.

[0020] The process of moving the end effector includes an acceleration process of increasing the torque of the motor to move, a constant speed process of moving while maintaining the torque of the motor within a predetermined deviation, and a deceleration process of decreasing the torque of the motor to move. The process of setting the time of the acceleration process may further be included.

[0021] In the process of setting the reference value, the collision determination reference value may be set according to the change rate of the torque value of the motor with respect to the set time of the acceleration process.

[0022] The method of operating the substrate transport device may further include a process of setting a measurement period for the torque value of the motor in accordance with the set time of the acceleration process, and in the process of setting the measurement period, the measurement period for the torque value of the motor may be set to be shorter than the set time of the acceleration process.

[0023] In the step of measuring the torque value of the motor, the torque value of the motor may be measured at least two times during the acceleration step.

[0024] In the step of measuring the torque value of the motor, the torque value of the motor may be measured at least at a starting point of the acceleration process. Effect of the Invention

[0025] A substrate transport apparatus according to an embodiment of the present invention can effectively detect an end-effector collision by calculating a torque differential value between two torque measurements measured at a time interval using a collision detection unit and determining an end-effector collision based on the calculated torque differential value. As a result, the motor can be stopped or rotated in the reverse direction to minimize damage caused by the end-effector collision.

[0026] In other words, by using two torque measurement values ​​measured with a time difference rather than the absolute amount (or value) of torque, and determining the collision of the end effector using the amount of torque change over time (or per unit time), it is possible to detect the collision of the end effector regardless of the moving speed and moving distance of the end effector, and it is possible to effectively detect the collision of the end effector both when the end effector moves while accelerating or decelerating and when the end effector moves at a constant speed, and it is also unnecessary to subdivide and vary the collision judgment criteria value according to the moving speed and moving distance of the end effector. [Brief description of the drawings]

[0027]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0028] Hereinafter, embodiments of the present invention will be described in more detail based on the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and can be embodied in various different forms. These embodiments are merely provided to make the disclosure of the present invention complete and to fully inform those with ordinary knowledge of the scope of the invention. In describing the present invention, the same reference numerals are assigned to the same components, and the drawings may be partially exaggerated in size for the purpose of accurately explaining the embodiments of the present invention. In the drawings, the same reference numerals indicate the same components.

[0029] FIG. 1 is a schematic diagram showing a substrate transfer device according to an embodiment of the present invention. FIG. 1(a) is a plan view of the substrate transfer device, and FIG. 1(b) is a block diagram of the collision detection unit.

[0030] Referring to FIG. 1, a substrate transfer device 100 according to an embodiment of the present invention may include an end effector 110 that supports a substrate 10, a motor 120 that provides power for the movement of the end effector 110, a collision detection unit 130 that detects a collision of the end effector 110, and a control unit 140 that controls the driving of the motor 120 in response to the collision detection by the collision detection unit 130.

[0031] The end-effector 110 can support the substrate 10 and can extend in the first direction. For example, the end-effector 110 may have a fork shape having a plurality of fingers arranged (or arrayed) in a second direction intersecting the first direction so as to be aligned in the first direction, and can support the substrate 10 in contact with the lower surface of the substrate 10. Here, the second direction may be a direction intersecting the first direction among the horizontal directions, and may be the left-right direction when the first direction is the front-rear direction. Further, the end-effector 110 may be made of a ceramic material such as quartz, aluminum oxide (Al2O3), aluminum nitride (AlN), silicon carbide (SiC), titanium dioxide (TiO2), silicon dioxide (SiO2). At this time, the substrate 10 may be a wafer, and is not particularly limited thereto, and may be a glass substrate or the like.

[0032] On the other hand, the end-effector 110 may be composed of a plurality and arranged (or stacked) in multiple stages (or a third direction intersecting both the first direction and the second direction), and the substrate 10 is supported on each stage (that is, each of the plurality of end-effectors), and two or more substrates 10 corresponding to the number of the plurality of end-effectors 110 can be transported collectively.

[0033] The motor 120 can provide power for the movement of the end effector 110, and the end effector 110 can be moved through the mechanical movement of the arms 111, 112, and 113 connected to the end effector 110 by the power. For example, the power can be provided to the arms 111, 112, and 113 by rotating the rotating shafts 21, 22, and 23 of the motor 120, and the rotation speeds of the rotating shafts 21, 22, and 23 can be controlled by the control unit 140. At this time, as shown in FIG. 1(a), the ends are connected between the arms 111, 112, and 113, and the end effector 110 can also be moved by performing joint movement due to the rotation of the rotating shafts 21, 22, and 23. The arm 113 to which the end effector 110 is connected can also be moved along a guide rail (not shown) by the rotational force of the motor 120 to move the end effector 110.

[0034] For example, when performing joint movement by the rotation of the rotating shafts 21, 22, and 23, the substrate transfer device 100 of the present invention may include three arms 111, 112, and 113 and three rotating shafts 21, 22, and 23. One end of the first arm 111 is fixed (or connected) to the first rotating shaft 21 and can rotate axially about the first rotating shaft 21.

[0035] And one end of the second arm 112 may be connected to the other end of the first arm 111 by the second rotating shaft 22 and can rotate axially about the second rotating shaft 22.

[0036] Also, one end of the third arm 113 may be connected to the other end of the second arm 112 by the third rotating shaft 23, and the other end thereof may be connected to the end effector 110 and can rotate axially about the third rotating shaft 23.

[0037] The first arm 111, the second arm 112, and the third arm 113 can rotate about the first rotation axis 21, the second rotation axis 22, and the third rotation axis 23, respectively, so that the position of the end effector 110 can be changed (or moved).

[0038] The collision detection unit 130 can detect a collision of the end effector 110 and can notify the control unit 140 of the presence or absence of collision detection so as to control the drive of the motor 120. For example, when the collision detection unit 130 detects a collision of the end effector 110, it can generate a collision detection signal and transmit it to the control unit 140.

[0039] The control unit 140 can control the drive of the motor 120 according to the collision detection of the collision detection unit 130 and can control the rotation speeds of the rotation axes 21, 22, and 23. For example, if the collision detection signal is transmitted from the collision detection unit 130, the control unit 140 can generate a control signal for controlling the rotation speeds of the rotation axes 21, 22, and 23 and transmit it to the motor 120.

[0040] Here, the collision detection unit 130 may include a torque measurement unit 131 that measures the torque value of the motor 120, a difference value calculation unit 132 that calculates a torque difference value (Difference value; D) between two torque measurement values measured with a time difference, and a collision determination unit 133 that determines a collision of the end effector 110 based on the torque difference value D. The torque measurement unit 131 can measure the torque value of the motor 120, and can sense the speeds of the rotating shafts 21, 22, 23 of the motor 120 and / or the rotation angles of the rotating shafts 21, 22, 23. For example, the torque measurement unit 131 may include an encoder, a tacho generator (speed generator), etc. that sense the speeds of the rotating shafts 21, 22, 23 of the motor 120, the rotation angles of the rotating shafts 21, 22, 23, or the rotation torque of the rotating shafts 21, 22, 23. At this time, the numerical value (or current amount) of the current supplied to the motor 120 when the motor 120 is driven can be converted into the torque of the motor 120 to measure (or measure) the torque value of the motor 120.

[0041] FIG. 2 is a graph showing the (current) torque measurement values for each period and the immediately preceding period torque measurement values for each period. Here, the dashed rectangle indicates the portion (or time point) where a collision of the end effector occurred.

[0042] Referring to FIG. 2, the difference value calculation unit 132 can calculate the torque difference value D between two torque measurement values measured with a time difference, and can calculate the torque difference value D between the currently measured torque measurement value (or current torque measurement value) and the torque measurement value measured (or previous torque measurement value) before (a predetermined time). Here, the difference value calculation unit 132 can subtract (or subtract) the torque measurement value measured before a predetermined time (i.e., the previous torque measurement value) from the torque measurement value measured in real time (i.e., the current torque measurement value) to calculate the torque difference value D in real time, and the torque difference value D can also be shown as an absolute value.

[0043] The collision determination unit 133 can determine the collision of the end effector 110 based on the torque difference value D, and can determine that it is a collision of the end effector 110 when the torque difference value D is equal to or greater than a critical torque difference value (or a collision determination reference value). That is, the collision determination unit 133 does not compare the torque measurement value measured in real time with the torque critical value, but subtracts (or subtracts) the torque measurement value measured before the predetermined time from the torque measurement value measured in real time. The torque difference value D thus obtained is compared with the critical torque difference value to determine the collision of the end effector 110.

[0044] Conventionally, while moving the end effector 110 in the same manner as during the conveyance (process) of the substrate conveyance apparatus 100 in advance, the torque value of the motor 120 is measured, and the torque critical value is set to be about 1.5 to 2 times higher than the highest numerical value (or the maximum value) of the measured torque value of the motor 120. When the torque measurement value measured in real time during the conveyance of the substrate conveyance apparatus 100 is equal to or greater than the torque critical value, it is determined that there is a collision of the end effector 110, and the driving of the motor 120 is stopped. In such a case, since the torque value of the motor 120 generated during the acceleration drive of the motor 120 is (very) larger than the torque value of the motor 120 generated during the constant speed drive of the motor 120, the torque critical value that is larger than the torque value of the motor 120 generated during the acceleration drive of the motor 120 is much larger than the torque measurement value (or the torque value of the motor generated during the constant speed drive of the motor) that is normally (or generally) measured during the constant speed drive of the motor 120. As a result, the difference between the torque critical value and the torque measurement value normally measured during the constant speed drive of the motor 120 becomes very large. As a result, it becomes difficult to effectively detect the collision of the end effector 110 generated during the constant speed drive of the motor 120.

[0045] In order to solve such problems, the acceleration drive of the motor 120, the constant-speed drive of the motor 120, and the deceleration drive of the motor 120 are classified according to the speeds of the rotating shafts 21, 22, and 23 of the motor 120 (or the rotational speeds of the rotating shafts), and the torque critical values are respectively specified (differently) for each drive (or for each of the acceleration drive of the motor, the constant-speed drive of the motor, and the deceleration drive of the motor). However, in such a case, the time for each drive will be different according to the moving distance and / or moving speed of the end effector 110, and the highest numerical value of the torque value of the motor 120 measured during conveyance (process) in each drive (particularly, the highest numerical value of the torque value of the motor measured during conveyance in the acceleration drive of the motor) will be different. Therefore, there is a problem that it becomes necessary to newly (again) specify the torque critical values for each drive every time the moving distance and / or moving speed of the end effector 110 differ.

[0046] However, in the substrate transfer device 100 of the present invention, since the torque difference value D is compared with the critical torque difference value to determine the collision of the end effector 110, it is possible to effectively detect the collision of the end effector 110 occurring in all drives (all of the acceleration drive of the motor, the constant-speed drive of the motor, and the deceleration drive of the motor) with one critical torque difference value. Since the critical torque difference value does not have a strong correlation with the highest numerical value of the torque value of the motor 120 measured during conveyance in each drive, there is also no problem (no need to specify) that it becomes necessary to newly set (or specify) the critical torque difference value every time the moving distance and / or moving speed of the end effector 110 differ.

[0047] Furthermore, the collision detection unit 130 may further include a reference value setting unit 134 that sets a collision determination reference value. The reference value setting unit 134 can set the collision determination reference value, and the collision determination reference value may be the critical torque difference value indicating a sudden change in the torque measurement value (or that the current torque measurement value has suddenly become much larger than the previous torque measurement value), rather than the torque critical value. For example, the reference value setting unit 134 experimentally (or empirically) measures in advance the torque value (average value) of the motor 120 due to the collision of the end effector 110, and appropriately sets (or determines) the collision determination reference value between the torque value of the motor 120 due to the collision of the end effector 110 measured in advance and the maximum value of the change amount (or the torque difference value) of the torque value per unit time in normal times.

[0048] Therefore, based on the torque difference value D, while determining the collision of the end effector 110, the collision determination unit 133 can determine that it is a collision of the end effector 110 when the torque difference value D is equal to or greater than the collision determination reference value, and can determine that it is a collision of the end effector 110 by confirming that the torque difference value D has become equal to or greater than the critical torque difference value. When a collision of the end effector 110 occurs, since the currently measured torque measurement value suddenly (very) increases, the torque difference value D can also suddenly increase and can become equal to or greater than the collision determination reference value (i.e., equal to or greater than the critical torque difference value). Thereby, when the torque difference value D is equal to or greater than the collision determination reference value, the collision determination unit 133 can recognize that the currently measured torque measurement value has suddenly (very) increased and determine that it is a collision of the end effector 110.

[0049] At this time, when the collision determination unit 133 determines a collision of the end effector 110, the control unit 140 can stop the driving of the motor 120 or drive the motor 120 in the reverse direction. When the collision determination unit 133 determines a collision of the end effector 110, the control unit 140 can stop the driving of the motor 120 or drive the motor 120 in the reverse direction, stop the driving of the motor 120 to reduce damage caused by the collision of the end effector 110 (for example, damage to the substrate transfer device and / or the collision object or defects in the substrate, etc.), and drive the motor 120 in the reverse direction to minimize the damage caused by the collision of the end effector 110.

[0050] Further, the collision detection unit 130 may further include a measurement position storage unit 135 that records the measurement position of the torque value. The measurement position storage unit 135 can record (or store) the measurement position of the torque value, and it is possible to know at what position the torque value of the motor 120 is measured. For example, the position of the end effector 110 (associated with the driving of the motor) can be recorded using the measurement position of the torque value, or the measurement position of the torque value can be recorded using the rotation angles and / or rotation speeds of the rotation shafts 21, 22, and 23.

[0051] Through this, the control unit 140 can drive the motor 120 to the previous measurement position (for example, the immediately previous measurement position) and then stop the driving of the motor 120. When the collision determination unit 133 determines a collision of the end effector 110, the control unit 140 can drive the motor 120 in the reverse direction, drive the motor 120 in the reverse direction to adjust (or move) the position of the end effector 110 or the rotation angles (or rotation speeds) of the rotary shafts 21, 22, 23 to the previous measurement position, and stop the driving of the motor 120 at the previous measurement position. Here, the previous measurement position may be the immediately previous measurement position, and it is possible to check (or inspect) the damage caused by the collision of the end effector 110. When maintenance of the end effector 110 is performed at the previous measurement position (that is, the immediately previous measurement position) or when the damage caused by the collision of the end effector 110 is very slight, the conveyance (process) can be continued again while measuring (or recording) the torque value of the motor 120 and the measurement position of the torque value (periodically) from the previous measurement position.

[0052] Therefore, in the substrate conveyance device 100 according to the present invention, the control unit 140 can drive the motor 120 in the reverse direction to the previous measurement position using the measurement position storage unit 135, making it easy to perform maintenance while suppressing the damage caused by the collision of the end effector 110 as much as possible, and improving the confirmation of the damage caused by the collision of the end effector 110 and / or the continuity of the conveyance (process) after the maintenance.

[0053] FIG. 3 is a conceptual diagram for explaining the calculation of the torque difference value according to an embodiment of the present invention. FIG. 3(a) is a partially enlarged graph of a graph of torque measurement values for each period and the immediately preceding period torque measurement value for each period, and FIG. 3(b) is a graph showing the torque difference value between the torque measurement value for each period and the immediately preceding period torque measurement value. Here, FIG. 3(a) is a graph showing an enlarged view of the rectangular portion of the dashed-dotted line in FIG. 2, and the rectangular portion of the dashed-dotted line in FIG. 3(b) indicates the portion where the collision of the end effector occurred, similar to the rectangular portion of the dashed-dotted line in FIG. 2.

[0054] Referring to FIGS. 2 and 3, the torque measurement unit 131 can measure the torque value of the motor 120 at a predetermined period T, and the difference value calculation unit 132 can calculate a torque difference value D between the torque measurement value of the current period and the torque measurement value of the immediately preceding period for each of the predetermined periods T. The torque measurement unit 131 can measure the torque value of the motor 120 at a predetermined period T, and according to the predetermined period T, can determine (or specify) the object to be compared (or calculated) with the currently measured torque measurement value (that is, the torque measurement value measured at a different time). At this time, the currently measured torque measurement value can be compared with the torque measurement value measured in the immediately preceding period (or the torque measurement value of the immediately preceding period), and the torque measurement value measured in the immediately preceding period can be subtracted (or subtracted) from the currently measured torque measurement value.

[0055] Here, the differential value calculation unit 132 can calculate a torque differential value D between the torque measurement value of the current cycle (i.e., the torque measurement value currently measured) and the torque measurement value of the immediately preceding cycle (i.e., the torque measurement value measured in the immediately preceding cycle) for each of the predetermined periods T. Thereby, while measuring the torque measurement value of the current cycle in real time, the torque differential value D can be calculated in real time, and the collision of the end effector 110 can be determined by comparing the torque differential value D calculated for each of the predetermined periods T with the collision determination reference value. Through this, the collision of the end effector 110 can be detected (or determined) with respect to the entire time of the conveyance (process).

[0056] The collision detection unit 130 may further include a measurement value storage unit 136 that stores the measured torque value of the motor 120. The measurement value storage unit 136 can store the measured torque value of the motor 120 and can measure and record (or store) the torque measurement value of the current cycle in real time. At this time, when the measured torque value of the motor 120 is stored in the measurement value storage unit 136, the measurement position storage unit 135 can record the measurement position of the torque value. Through this, the torque measurement value of the immediately preceding cycle can be read and compared (or calculated) with the torque measurement value of the current cycle currently measured. On the other hand, the measurement value storage unit 136 can repeatedly perform storage (or writing) and update (or deletion), and in such a case, the capacity of the storage location becomes small and the processing speed becomes fast.

[0057] When a stopped object is driven (or moved) and then stopped again, it will be accelerated and then decelerated. For stable driving (or moving), the object can be driven (or moved) at a constant speed between acceleration and deceleration.

[0058] For this purpose, the driving of the motor 120 may include an acceleration drive in which the torque of the motor 120 increases, a constant-speed drive in which the torque of the motor 120 is maintained within a predetermined deviation, and a deceleration drive in which the torque of the motor 120 decreases. The acceleration drive accelerates (or accelerates the movement of) the stopped end effector 110 and / or the rotational speeds of the rotary shafts 21, 22, 23. For this reason, the torque of the motor 120 may increase.

[0059] The constant-speed drive moves the end effector 110 at a constant speed (or rotates the rotary shaft), and for this reason, the torque of the motor 120 is maintained within a predetermined deviation.

[0060] The deceleration drive decelerates (or decelerates the movement of) the rotational speeds of the end effector 110 and / or the rotary shafts 21, 22, 23 to stop the end effector 110 and / or the rotary shafts 21, 22, 23. For this reason, the torque of the motor 120 may decrease.

[0061] Here, in the acceleration drive, since the torque of the motor 120 (greatly) increases, there is a possibility that the torque difference value D between the current torque measurement value and the previous torque measurement value becomes large. When the torque difference value D becomes large, the collision determination reference value also becomes large. When the collision determination reference value becomes large, there is a possibility that the sensitivity of the collision detection of the end effector 110 decreases. In particular, in the constant-speed drive, since the average value of the torque difference value D is very low and close to "0", even if the torque difference value D increases due to a collision of the end effector 110, it does not exceed the increased collision determination reference value. As a result, even if a collision of the end effector 110 occurs, there is a possibility that it cannot be detected.

[0062] The substrate transfer device 100 according to the present invention may further include an acceleration time setting unit 150 that sets the time of the acceleration drive.

[0063] The acceleration time setting unit 150 can set the time of the acceleration drive and can adjust the change amount of the torque value per unit time (or per one cycle T) in the acceleration drive. For example, the acceleration time setting unit 150 can adjust the time of the acceleration drive to lower the maximum value of the change amount of the torque value per unit time (or the torque difference value) in the acceleration drive, and through this, can lower the collision determination reference value determined according to the maximum value of the change amount of the torque value per unit time.

[0064] At this time, the change amount (the maximum value) of the torque value per unit time can become lower as the maximum torque value in the acceleration drive is smaller and as the time of the acceleration drive is longer, and the time of the acceleration drive can be appropriately determined according to the moving distance of the end effector 110. When the moving distance of the end effector 110 becomes shorter, the time of the acceleration drive relatively has to become shorter, and the maximum torque value in the acceleration drive also becomes smaller. On the contrary, if the moving distance of the end effector 110 is sufficiently long, for smooth (or high-speed) conveyance (process), the maximum torque value in the acceleration drive becomes larger, and the time of the acceleration drive can be set (longer) so that the change amount (the maximum value) of the torque value per unit time becomes lower according to the increased maximum torque value in the acceleration drive.

[0065] Here, the reference value setting unit 134 can set the collision determination reference value according to the change rate (or change amount) of the torque value of the motor 120 with respect to the set acceleration drive time. If the change rate of the torque value of the motor 120 with respect to the set acceleration drive time (the change amount of the torque value of the motor / the set acceleration drive time) is large, the torque difference value D (or the change amount of the torque value per unit time) in the acceleration drive becomes large, and the collision determination reference value can be set large. Conversely, if the change rate of the torque value of the motor 120 with respect to the set acceleration drive time is small, the torque difference value D becomes small in the acceleration drive, and as a result, the collision determination reference value can be set small. That is, the reference value setting unit 134 can set the collision determination reference value in proportion to the change rate of the torque value of the motor 120 with respect to the set acceleration drive time.

[0066] At this time, (experimentally or empirically), since the maximum torque value in the acceleration drive is fixed (or determined) according to the moving distance of the end effector 110, the collision determination reference value can be set according to the set acceleration drive time, and the maximum value of the change amount of the torque value per unit time (in the acceleration drive) is determined according to the set acceleration drive time. It is possible to prevent the end effector 110 from being determined to be in a collision even when there is no collision of the end effector 110 until the collision determination reference value becomes larger than the maximum value of the change amount of the torque value per unit time. Therefore, the reference value setting unit 134 can set the collision determination reference value to be larger than the maximum value of the change amount of the torque value per unit time according to the set acceleration drive time.

[0067] And the collision detection unit 130 may further include a measurement period setting unit 137 that sets a measurement period T of the torque value of the motor 120 according to the set acceleration drive time. The measurement period setting unit 137 can set the measurement period T of the torque value of the motor 120 according to the set acceleration drive time, whereby the torque value of the motor 120 can be measured at the set period (i.e., the predetermined period), and while measuring the torque value of the motor 120 for each set period T, the collision of the end effector 110 can be detected (or determined) in real time by comparing with the torque measurement value of the previous period.

[0068] For example, the measurement period setting unit 137 can set the measurement period T of the torque value of the motor 120 so as to measure the torque value of the motor 120 at least once in the acceleration drive according to the set acceleration drive time, and can set the measurement period T of the torque value of the motor 120 so as to measure the torque value of the motor 120 at least two or more times for detecting the collision of the end effector 110 effective in the acceleration drive. When the torque value of the motor 120 is first measured once in the acceleration drive, the torque value of the motor 120 measured first (or at first) can be compared (or calculated) with "0", and the measured torque value of the motor 120 can be the same as the torque difference value D.

[0069] At this time, the measurement period setting unit 137 can set the measurement period T of the torque value of the motor 120 to be shorter than the set acceleration drive time. In order to detect the collision of the end effector 110 even during the acceleration drive, the torque value of the motor 120 must be measured at least once during the acceleration drive. For this purpose, the measurement period setting unit 137 can set the measurement period T of the torque value of the motor 120 to be shorter than the set acceleration drive time. Thereby, the collision of the end effector 110 can be detected even during the acceleration drive, and the collision of the end effector 110 occurring in all drives (all of the acceleration drive of the motor, the constant speed drive of the motor, and the deceleration drive of the motor) can be effectively detected.

[0070] For example, the measurement period setting unit 137 can set the measurement period T of the torque value of the motor 120 to be within 4 to 12 milliseconds (ms), and can set the measurement period T of the torque value of the motor 120 to be a short time (for example, 4 to 12 ms) such that there is no damage to the end effector 110 and the substrate 10, or such that the damage can be minimized.

[0071] Then, the torque measurement unit 131 can measure the torque value of the motor 120 at least twice or more in the acceleration drive (section). If the torque value of the motor 120 is not measured even once in the acceleration drive (section), the collision of the end effector 110 cannot be detected in the acceleration drive (section). If the torque value of the motor 120 is measured only once in the acceleration drive (section), since the measured torque value of the motor 120 is the same as the torque difference value D, the maximum value of the torque value of the motor 120 increases, and the collision determination reference value has to increase. When the collision determination reference value increases, the sensitivity of detecting the collision of the end effector 110 decreases. In particular, since the sensitivity of detecting the collision of the end effector 110 decreases during the constant-speed drive, the torque measurement unit 131 can measure the torque value of the motor 120 at least twice or more in the acceleration drive (section) so that the sensitivity of detecting the collision of the end effector 110 is improved in all drives (all of the acceleration drive of the motor, the constant-speed drive of the motor, and the deceleration drive of the motor).

[0072] Here, the torque measurement unit 131 can measure the torque value of the motor 120 at least at the start point (or start time) of the acceleration drive. The torque measurement unit 131 can measure the torque value of the motor 120 at the origin (or the start point of the acceleration drive), can measure the torque value of the motor 120 at the origin before starting the acceleration drive, and can also measure the torque value of the motor 120 at the origin at 0 cycle T. The torque value of the motor 120 measured at the start point of the acceleration drive (or the origin) can be compared (or calculated) with the torque value of the motor 120 that is first measured after being acceleration-driven, and the torque difference value D can be calculated by subtracting (or subtracting) the torque value of the motor 120 measured at the start point of the acceleration drive (or 0 cycle torque measurement value) from the torque value of the motor 120 that is first measured (or torque measurement value of 1 cycle). Thereby, even if only the torque value of the motor 120 in 1 cycle T is measured in the acceleration drive, the torque difference value D can be calculated by subtracting (or subtracting) the torque measurement value in 0 cycle T (or the torque value of the motor measured at the start point of the acceleration drive) from the torque measurement value in 1 cycle T, and the collision of the end effector 110 can be detected in the acceleration drive.

[0073] On the other hand, the calculation of the torque measurement value in 0 cycle T and the like with the torque measurement value in 1 cycle T in 1 cycle T can be performed in the difference value calculation unit 132, and can also be performed in other components of the collision detection unit 130. At this time, the torque measurement value in 0 cycle T may not be "0", may be smaller than 0, or may be forcibly fixed to "0". When forcibly fixed to "0", the torque value of the motor 120 cannot be directly (or substantially) measured at the start point of the acceleration drive, and the torque measurement value in 1 cycle T can also be calculated as the torque difference value D without calculation in the difference value calculation unit 132.

[0074] FIG. 4 is a flowchart showing an operation method of a substrate transfer device according to another embodiment of the present invention.

[0075] Based on FIG. 4, the operation method of the substrate transfer device according to another embodiment of the present invention will be described in more detail. However, matters overlapping with the parts previously described in relation to the substrate transfer device according to an embodiment of the present invention will be omitted.

[0076] The operation method of the substrate transfer device according to another embodiment of the present invention may include a process (S100) of moving an end effector that supports a substrate by providing power via a motor, a process (S200) of measuring the torque value of the motor multiple times with a time difference, a process (S300) of calculating a torque difference value between two measured torque measurement values, and a process (S400) of determining a collision of the end effector based on the calculated torque difference value.

[0077] First, move an end effector that supports a substrate by providing power via a motor (S100). By providing power via a motor, the end effector that supports the substrate can be moved, and through this, the substrate can be transferred. Here, the control unit can control the driving of the motor and adjust (or regulate) the movement of the end effector.

[0078] Next, measure the torque value of the motor multiple times with a time difference (S200). The torque value of the motor can be measured multiple times during the movement of the end effector, and the torque measurement unit of the collision detection unit can measure the torque value of the motor multiple times with a time difference. For example, the torque measurement unit can measure the torque value of the motor at a predetermined period.

[0079] Next, calculate the torque difference value between the two measured torque measurement values (S300). While measuring the torque value of the motor multiple times, the torque difference value (Difference value) between two torque measurement values measured with a time difference can be calculated, and the difference value calculation unit of the collision detection unit can calculate the torque difference value between two torque measurement values among the multiple torque measurement values measured multiple times with the time difference. For example, the torque difference value between the currently measured torque measurement value (or the current torque measurement value) and the torque measurement value (or the previous torque measurement value) measured (a predetermined time) ago can be calculated, and the torque difference value can be calculated in real time by subtracting (or subtracting) the torque measurement value measured (a predetermined time) ago from the torque measurement value measured in real time (i.e., the current torque measurement value), and the torque difference value can also be shown as an absolute value.

[0080] Then, based on the calculated torque difference value, determine whether the end effector has collided (S400). Based on the calculated torque difference value, it is possible to determine whether the end effector has collided, and the collision determination unit of the collision detection unit can determine whether the end effector has collided based on the torque difference value. When the torque difference value is equal to or greater than the critical torque difference value (or the collision determination reference value), it can be determined that the end effector has collided. For example, instead of comparing the torque measurement value measured in real time with the torque critical value, the collision determination unit can compare the torque difference value obtained by subtracting (or subtracting) the torque measurement value measured (a predetermined time) ago from the torque measurement value measured in real time with the critical torque difference value to determine whether the end effector has collided.

[0081] The operation method of the substrate transfer device according to the present invention may further include a process of setting a collision determination reference value (S50), and a process of stopping the driving of the motor or driving the motor in the reverse direction (S500) when it is determined in the process of determining the collision of the end effector (S400) that the end effector has collided.

[0082] The collision determination reference value can be set (S50). The reference value setting unit of the collision detection unit can set the collision determination reference value, and the collision determination reference value may be a critical torque difference value indicating a sudden change in the torque measurement value (or that the current torque measurement value has suddenly become much larger than the previous torque measurement value), rather than a torque critical value. For example, the reference value setting unit can experimentally (or empirically) measure in advance the torque value (average value) of the motor due to the collision of the end effector, and appropriately set (or determine) the collision determination reference value between the torque value of the motor due to the collision of the end effector measured in advance and the maximum value of the change amount of the torque value (or the torque difference value) per unit time in normal times.

[0083] And when it is determined in the process of determining the collision of the end effector (S400) that the end effector has collided, the driving of the motor can be stopped or the motor can be driven in the reverse direction (S500). When the collision determination unit determines that the end effector has collided in the process of determining the collision of the end effector (S400), the control unit can stop the driving of the motor or drive the motor in the reverse direction. When the collision determination unit determines that the end effector has collided, the control unit can stop the driving of the motor or drive the motor in the reverse direction, and the damage caused by the collision of the end effector (for example, damage to the substrate transfer device and / or the collision object or defects in the substrate, etc.) can be reduced, and the damage caused by the collision of the end effector can be minimized by driving the motor in the reverse direction.

[0084] In the process (S400) of determining the collision of the end effector, when the calculated torque difference value is greater than or equal to the set collision determination reference value, it can be determined that there is a collision of the end effector. In the process (S400) of determining the collision of the end effector, while the collision determination unit determines the collision of the end effector based on the torque difference value, when the torque difference value is greater than or equal to the set collision determination reference value, it can be determined that there is a collision of the end effector, and it can be confirmed that the torque difference value has become greater than or equal to the critical torque difference value, and it can be determined that there is a collision of the end effector. When a collision of the end effector occurs, since the currently measured torque measurement value suddenly (very) increases, the torque difference value also suddenly increases and becomes greater than or equal to the collision determination reference value (that is, greater than or equal to the critical torque difference value). Thereby, when the torque difference value is greater than or equal to the collision determination reference value, the collision determination unit can recognize that the currently measured torque measurement value has suddenly (very) increased and determine that there is a collision of the end effector.

[0085] The operation method of the substrate transfer device according to the present invention may further include a process (S250) of recording the measurement position of the torque value.

[0086] The measurement position of the torque value can be recorded (S250). The measurement position storage unit of the collision detection unit can record (or store) the measurement position of the torque value, and it can be known at what position the torque value of the motor is measured. For example, the position of the end effector (associated with the drive of the motor) can be recorded with the measurement position of the torque value, or the measurement position of the torque value can be recorded with the rotation angle and / or the number of rotations of the rotating shaft.

[0087] And the process (S500) of stopping the drive of the motor or driving the motor in the reverse direction may include a process (S510) of driving the motor to the previous measurement position and then stopping the drive of the motor.

[0088] After driving the motor to the previous measurement position, the drive of the motor can be stopped (S510). After the control unit drives the motor to the previous measurement position (for example, the immediately previous measurement position), the drive of the motor can be stopped. When the collision determination unit determines a collision of the end effector, the control unit can drive the motor in the reverse direction, and by driving the motor in the reverse direction, the position of the end effector or the rotation angle (or rotation speed) of the rotation axis can be adjusted (or moved) to the previous measurement position, and the drive of the motor can be stopped at the previous measurement position. Here, the previous measurement position may be the immediately previous measurement position, the damage caused by the collision of the end effector can be confirmed (or inspected), when maintenance of the end effector is performed at the previous measurement position (that is, the immediately previous measurement position), or when the damage caused by the collision of the end effector is very slight, the conveyance (process) can be continued again while measuring (or recording) the torque value of the motor and the measurement position of the torque value (periodically) from the previous measurement position.

[0089] Therefore, in the operation method of the substrate transfer device according to the present invention, the measurement position of the torque value can be recorded and the motor can be driven in the reverse direction to the previous measurement position, making it easy to perform maintenance while minimizing the damage caused by the collision of the end effector, and improving the continuity of the conveyance (process) after confirming the damage caused by the collision of the end effector and / or after the maintenance.

[0090] The operation method of the substrate transfer device according to the present invention may further include a process (S240) of storing the measured torque value of the motor.

[0091] The measured torque value of the motor can be stored (S240). The measurement value storage unit of the collision detection unit can store the measured torque value of the motor, and can measure and record (or store) the torque measurement value of the current cycle in real time. At this time, when the measured torque value of the motor is stored in the measurement value storage unit, the measurement position of the torque value can be recorded in the measurement position storage unit. Through this, the torque measurement value of the previous cycle can be read and compared (or calculated) with the torque measurement value of the currently measured current cycle. On the other hand, the torque value of the motor stored in the measurement value storage unit can be updated (periodically). That is, the measurement value storage unit can repeatedly perform storage (or writing) and update (or deletion), and in such a case, the capacity of the storage location becomes smaller and the processing speed becomes faster.

[0092] In the process of measuring the torque value of the motor (S200), the torque value of the motor can be measured at a predetermined cycle. In the process of calculating the torque difference value (S300), the torque difference value between the torque measurement value of the current cycle and the torque measurement value of the previous cycle can be calculated for each predetermined cycle. In the process of measuring the torque value of the motor (S200), the torque measurement unit can measure the torque value of the motor at a predetermined cycle, and according to the predetermined cycle, the object to be compared (or calculated) with the currently measured torque measurement value (that is, the torque measurement values measured at different times) can be determined (or specified). At this time, the currently measured torque measurement value can be compared with the torque measurement value measured in the previous cycle (or the torque measurement value of the previous cycle), and the torque measurement value measured in the previous cycle can be subtracted (or subtracted) from the currently measured torque measurement value.

[0093] And in the process (S300) of calculating the torque difference value, the difference value calculation unit can calculate the torque difference value between the torque measurement value of the current cycle (i.e., the torque measurement value currently measured) and the torque measurement value of the immediately preceding cycle (i.e., the torque measurement value measured in the immediately preceding cycle) for each of the predetermined periods. Thereby, while measuring the torque measurement value of the current cycle in real time, the torque difference value can be calculated in real time, and the collision of the end effector can be determined by comparing the torque difference value calculated for each of the predetermined periods with the collision determination reference value. Through this, the collision of the end effector can be detected (or determined) with respect to the entire time of the conveyance (process).

[0094] The process (S100) of moving the end effector may include an acceleration process (S110) of increasing the torque of the motor to move, a constant speed process (S120) of moving while holding the torque of the motor within a predetermined deviation, and a deceleration process (S130) of decreasing the torque of the motor to move.

[0095] The acceleration process (S110) of increasing the torque of the motor to move accelerates (or accelerates the movement of) the rotational speed of the stopped end effector and / or the rotating shaft, and for this purpose, the torque of the motor may be increased.

[0096] The constant speed process (S120) of moving while holding the torque of the motor within a predetermined deviation moves the end effector at a constant speed (or rotates the rotating shaft), and for this purpose, the torque of the motor may be held within a predetermined deviation.

[0097] The deceleration process (S130) of decreasing the torque of the motor to move decelerates (or decelerates the movement of) the rotational speed of the end effector and / or the rotating shaft to stop the end effector and / or the rotating shaft, and for this purpose, the torque of the motor may be decreased.

[0098] Here, in the acceleration process (S110), since the torque of the motor increases (significantly), there is a possibility that the torque difference value between the current torque measurement value and the previous torque measurement value may become large. When the torque difference value becomes large, the collision determination reference value also becomes large. When the collision determination reference value becomes large, there is a possibility that the sensitivity of the collision detection of the end effector may decrease. In particular, in the constant speed process (S120), since the average value of the torque difference value is very low, close to "0", even if the torque difference value increases due to a collision of the end effector, it does not exceed the increased collision determination reference value. As a result, there is a possibility that even if a collision of the end effector occurs, it cannot be detected.

[0099] The operation method of the substrate transfer device according to the present invention may further include a process (S40) of setting the time of the acceleration process (S110).

[0100] The time of the acceleration process (S110) can be set (S40). The acceleration time setting unit can set the time of the acceleration process (S110) and can adjust the change amount of the torque value per unit time (or per one cycle T) in the acceleration process (S110). For example, the acceleration time setting unit can adjust the time of the acceleration process (S110) to lower the maximum value of the change amount of the torque value per unit time (or the torque difference value) in the acceleration process (S110). Through this, the collision determination reference value determined according to the maximum value of the change amount of the torque value per unit time can be lowered.

[0101] At this time, the change amount (maximum value) of the torque value per unit time can be made lower as the maximum torque value in the acceleration process (S110) is smaller and as the time of the acceleration process (S110) is longer, and the time of the acceleration process (S110) can be appropriately determined according to the moving distance of the end effector. When the moving distance of the end effector becomes shorter, the time of the acceleration process (S110) must relatively become shorter, and the maximum torque value in the acceleration process (S110) also becomes smaller. On the contrary, if the moving distance of the end effector is sufficiently long, the maximum torque value in the acceleration process (S110) becomes larger for smooth (or high-speed) conveyance (process), and according to the increased maximum torque value in the acceleration process (S110), the time of the acceleration process (S110) can be set (longer) so that the change amount (maximum value) of the torque value per unit time becomes lower.

[0102] Here, in the process (S50) of setting the reference value, the collision determination reference value can be set according to the change rate (or change amount) of the torque value of the motor with respect to the set time of the acceleration process (S110). If the change rate of the torque value of the motor with respect to the set time of the acceleration process (S110) (change amount of the torque value of the motor / set time of the acceleration process) is large, as a result, the torque difference value (or the change amount of the torque value per unit time) in the acceleration process (S110) becomes large, and thus the collision determination reference value can be set large. Conversely, if the change rate of the torque value of the motor with respect to the set time of the acceleration process (S110) is small, as a result, the torque difference value in the acceleration process (S110) becomes small, and thus the collision determination reference value can be set small. That is, the reference value setting unit can set the collision determination reference value in proportion to the change rate of the torque value of the motor with respect to the set time of the acceleration process (S110).

[0103] At this time, since the maximum torque value in the acceleration process (S110) is fixed (or determined) according to the moving distance of the end effector (experimentally or empirically), the collision determination reference value can be set according to the set time of the acceleration process (S110), and according to the set time of the acceleration process (S110), the maximum value of the change amount of the torque value per unit time (in the acceleration process) is determined. Only when the collision determination reference value is greater than the maximum value of the change amount of the torque value per unit time, it is possible to prevent the determination that the end effector has collided even if the end effector does not actually collide. Therefore, in the process (S50) of setting the reference value, the reference value setting unit can set the collision determination reference value to be greater than the maximum value of the change amount of the torque value per unit time according to the set time of the acceleration process (S110).

[0104] The operation method of the substrate transfer device according to the present invention may further include a process (S45) of setting the measurement period of the torque value of the motor according to the set time of the acceleration process (S110).

[0105] The measurement period of the torque value of the motor can be set according to the set time of the acceleration process (S110) (S45). The measurement period setting unit of the collision detection unit can set the measurement period of the torque value of the motor according to the set time of the acceleration process (S110), whereby the torque value of the motor can be measured at the set period (that is, the predetermined period), and while measuring the torque value of the motor for each set period, the collision of the end effector can be detected (or determined) in real time by comparing with the torque measurement value of the previous period.

[0106] For example, the measurement period setting unit can set the measurement period of the torque value of the motor so as to measure the torque value of the motor at least once in the acceleration process (S110) according to the time of the set acceleration process (S110), and can set the measurement period of the torque value of the motor so as to measure the torque value of the motor at least two or more times for sensing the collision of the effective end effector in the acceleration process (S110). When the torque value of the motor is first measured once in the acceleration process (S110), the torque value of the motor measured first (or initially) can be compared (or calculated) with "0", and the measured torque value of the motor can be the same as the torque difference value.

[0107] In the process (S45) of setting the measurement period, the measurement period of the torque value of the motor can be set to be shorter than the time of the set acceleration process (S110). In the process (S45) of setting the measurement period, the measurement period setting unit can set the measurement period of the torque value of the motor to be shorter than the time of the set acceleration process (S110). In order to sense the collision of the end effector in the acceleration process (S110) as well, the torque value of the motor must be measured at least once in the acceleration process (S110). For this purpose, the measurement period setting unit can set the measurement period of the torque value of the motor to be shorter than the time of the set acceleration process (S110). Thereby, the collision of the end effector can be sensed also in the acceleration process (S110), and the collision of the end effector occurring in the process (S100) of moving the end effector (or the entire moving process of the end effector including the acceleration process, the constant speed process, and the deceleration process) can be effectively sensed.

[0108] For example, the measurement period setting unit can set the measurement period of the torque value of the motor to be within 4 to 12 milliseconds (ms), and can set the measurement period of the torque value of the motor to be a short time (for example, 4 to 12 ms) such that there is no damage to the end effector and the substrate, or the damage can be minimized.

[0109] In the process (S200) of measuring the torque value of the motor, the torque value of the motor can be measured at least twice or more in the acceleration process (S110). In the process (S200) of measuring the torque value of the motor, the torque measurement unit can measure the torque value of the motor at least twice or more in the acceleration process (S110). If the torque value of the motor is not measured even once in the acceleration process (S110), the collision of the end effector cannot be sensed in the acceleration process (S110). If the torque value of the motor is measured only once in the acceleration process (S110), since the measured torque value of the motor is the same as the torque difference value, the maximum value of the torque value of the motor increases, and the collision judgment reference value has to increase. When the collision judgment reference value increases, the sensitivity of the collision sensing of the end effector decreases. In particular, the sensitivity of the collision sensing of the end effector decreases in the constant speed process (S120). Therefore, in order to improve the sensitivity of the collision sensing of the end effector in all the movement processes of the end effector (all of the acceleration process, the constant speed process, and the deceleration process), the torque measurement unit can measure the torque value of the motor at least twice or more in the acceleration process (S110).

[0110] In the process (S200) of measuring the torque value of the motor, the torque value of the motor can be measured at least at the starting point (or starting time) of the acceleration process (S110). In the process (S200) of measuring the torque value of the motor, the torque measurement unit can measure the torque value of the motor at least at the starting point (or origin) of the acceleration process (S110). The torque measurement unit can measure the torque value of the motor at the origin (or the starting point of the acceleration process), can measure the torque value of the motor at the origin before starting the acceleration process (S110), and can also measure the torque value of the motor at the origin at 0 cycle (or the starting time of the acceleration process). The torque value of the motor measured at the starting point (or the origin) of the acceleration process (S110) can be compared (or calculated) with the torque value of the motor that is first measured when the end effector starts to move in the acceleration process (S110), and the torque difference value can be calculated by subtracting (or subtracting) the torque value of the motor measured at the starting point of the acceleration process (S110) (or 0 cycle torque measurement value) from the torque value of the motor that is first measured (or 1 cycle torque measurement value). Thereby, even if only the torque value of the motor for 1 cycle is measured in the acceleration process (S110), by subtracting (or subtracting) the torque measurement value of 0 cycle (or the torque value of the motor measured at the starting point of the acceleration process) from the torque measurement value of 1 cycle, the collision of the end effector in the acceleration process (S110) can be detected.

[0111] In this way, in the present invention, a torque difference between two torque measurements measured with a time difference is calculated using a collision detector, and a collision of the end effector is judged based on the torque difference, so that the collision of the end effector can be effectively detected, and damage caused by the collision of the end effector can be minimized by stopping the motor or rotating it in the reverse direction. That is, the collision of the end effector can be detected regardless of the moving speed and moving distance of the end effector by judging the collision of the end effector using the torque change amount with time using two torque measurements measured with a time difference, not the absolute amount of torque, and the collision of the end effector can be effectively detected both when the end effector moves while accelerating or decelerating and when the end effector moves at a constant speed, and it is not necessary to differentiate the collision judgment reference value according to the moving speed and moving distance of the end effector.

[0112] Although the preferred embodiment of the present invention has been illustrated and described above, the present invention is not limited to the above embodiment, and it should be understood that various modifications can be made thereto and equivalent other embodiments can be adopted by those skilled in the art without departing from the gist of the present invention as claimed in the claims. Therefore, the technical scope of protection of the present invention should be determined by the appended claims.

Claims

1. An end effector on which a substrate is supported, A motor that provides power for the movement of the end effector, A collision sensing unit that senses a collision of the end effector, A control unit that controls the driving of the motor in response to the collision sensed by the collision sensing unit, comprising wherein the collision sensing unit includes a torque measurement unit that measures a torque value of the motor, a difference value calculation unit that calculates a torque difference value between two torque measurement values measured with a time difference, and a collision determination unit that determines a collision of the end effector based on the torque difference value, A substrate transfer device comprising the above.

2. The collision sensing unit further includes a reference value setting unit that sets a collision determination reference value, The collision determination unit determines that there is a collision of the end effector when the torque difference value is equal to or greater than the collision determination reference value, The control unit stops the driving of the motor or drives the motor in the reverse direction when the collision determination unit determines a collision of the end effector. The substrate transfer device according to claim 1.

3. The collision sensing unit further includes a measurement position storage unit that records a measurement position of the torque value, The control unit drives the motor to the previous measurement position and then stops the driving of the motor. The substrate transfer device according to claim 2.

4. The collision sensing unit further includes a measurement value storage unit that stores the measured torque value of the motor, The torque measurement unit measures the torque value of the motor at a predetermined period, The difference value calculation unit calculates a torque difference value between the torque measurement value of the current period and the torque measurement value of the immediately previous period for each of the predetermined periods. The substrate transfer device according to claim 1.

5. The driving of the motor includes: an acceleration drive in which the torque of the motor increases; a constant-speed drive in which the torque of the motor is maintained within a predetermined deviation; a deceleration drive in which the torque of the motor decreases; and further includes an acceleration time setting unit for setting the time of the acceleration drive. The substrate transfer device according to claim 2.

6. The reference value setting unit sets the collision determination reference value according to the change rate of the torque value of the motor with respect to the set time of the acceleration drive. The substrate transfer device according to claim 5.

7. The collision detection unit further includes a measurement period setting unit for setting a measurement period of the torque value of the motor according to the set time of the acceleration drive. The measurement period setting unit sets the measurement period of the torque value of the motor to be shorter than the set time of the acceleration drive. The substrate transfer device according to claim 5.

8. The torque measurement unit measures the torque value of the motor at least two or more times during the acceleration drive. The substrate transfer device according to claim 5.

9. The torque measurement unit measures the torque value of the motor at least at the start point of the acceleration drive. The substrate transfer device according to claim 5.

10. A process of providing power through a motor to move an end effector on which a substrate is supported; a process of measuring the torque value of the motor multiple times with a time difference; a process of calculating a torque difference value between two measured torque measurement values; a process of determining a collision of the end effector based on the calculated torque difference value; including, an operation method of a substrate transfer device.

11.

11. The process of setting the collision determination reference value, and In the process of determining the collision of the end effector, when the collision of the end effector is determined, the process of stopping the driving of the motor or driving the motor in the reverse direction, and further includes In the process of determining the collision of the end effector, when the calculated torque difference value is equal to or greater than the set collision determination reference value, it is determined that there is a collision of the end effector. The operation method of the substrate transfer device according to claim 10.

12. further includes the process of recording the measurement position of the torque value, and The process of stopping the driving of the motor or driving the motor in the reverse direction includes the process of stopping the driving of the motor after driving the motor to the previous measurement position. The operation method of the substrate transfer device according to claim 11.

13. further includes the process of storing the measured torque value of the motor, and In the process of measuring the torque value of the motor, the torque value of the motor is measured at a predetermined period, and In the process of calculating the torque difference value, a torque difference value between the torque measurement value of the current period and the torque measurement value of the immediately previous period is calculated for each of the predetermined periods. The operation method of the substrate transfer device according to claim 10.

14. The process of moving the end effector is an acceleration process of increasing the torque of the motor and moving, a constant speed process of holding the torque of the motor within a predetermined deviation and moving, a deceleration process of decreasing the torque of the motor and moving, and includes further includes the process of setting the time of the acceleration process. The operation method of the substrate transfer device according to claim 11.

15. In the process of setting the reference value, the collision determination reference value is set according to the change rate of the torque value of the motor with respect to the time of the set acceleration process, the operation method of the substrate transfer device according to claim 14.

16. The method further includes a process of setting a measurement period of the torque value of the motor according to the set time of the acceleration process, In the process of setting the measurement period, the measurement period of the torque value of the motor is set to be shorter than the set time of the acceleration process, the operation method of the substrate transfer device according to claim 14.

17. In the process of measuring the torque value of the motor, the torque value of the motor is measured at least two or more times in the acceleration process, the operation method of the substrate transfer device according to claim 14.

18. In the process of measuring the torque value of the motor, the torque value of the motor is measured at least at the start point of the acceleration process, the operation method of the substrate transfer device according to claim 14.

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