Conveying unit, article conveying system, and control method for a conveying unit

Abstract

The present invention provides a transport unit travelling on a track arranged along a ceiling, the transport unit comprising a main body provided with a travel drive, a travel wheel rotating by receiving power from the travel drive, a gripping member configured to grip an article, a lifting member arranged between the main body and the gripping member and configured to move the gripping member in a vertical direction, and a controller, wherein the controller lowers or raises the gripping member while the transport unit travels on the track, wherein the controller controls the lifting member and the travel drive such that lowering or raising of the gripping member is performed in a constant speed segment in which the transport unit travels at a constant speed.

Description

TECHNICAL FIELD

[0001] The present application relates to a transfer unit, an article transfer system, and a control method of a transfer unit. BACKGROUND

[0002] Generally, in order to manufacture semiconductor devices, various types of processes such as deposition, photolithography, and etching are performed, and devices each of which performs one of these processes are arranged in a semiconductor production line. Articles such as substrates (e.g., wafers, glasses) which are objects to be processed in a semiconductor device manufacturing process can be provided to each semiconductor processing apparatus in a state of being accommodated in a container such as a FOUP or a POD. In addition, articles on which processes have been performed can be collected from each semiconductor processing apparatus into a container, and the container in which the articles are collected can be transferred to the outside.

[0003] The container is transferred by a transfer vehicle such as an overhead hoist transport (OHT) apparatus. The transfer vehicle travels on a track provided along the ceiling of the semiconductor production line. The transfer vehicle transfers the container in which the articles are accommodated to a load port of any one of the semiconductor processing devices. In addition, the transfer vehicle can pick up the container in which the processed articles are accommodated from the load port and transfer the container to the outside, or transfer the container to another one of the semiconductor processing devices.

[0004] Figure 1 is a diagram illustrating a method in which a transfer vehicle in the related art transfers a container to a port. Referring to Figure 1 Generally, the transfer vehicle A (such as an OHT apparatus) includes a gripper G for holding the container F, a belt B connected to the gripper G, and a lifter L for winding or unwinding the belt B to lift or lower the gripper G. Further, the transfer vehicle A travels along a track R. When traveling along the track R, the transfer vehicle A places the container F in the port P. In Figure 1 , AP denotes a travel path of the transfer vehicle A. In addition, in Figure 1 , GP denotes a movement path of the gripper G.

[0005] As can be seen from Figure 1 , the transfer vehicle A operates in the following order: moving to an upper portion of the port P and stopping; unwinding the belt B to lower the gripper G and the container F; and placing the container F down on the port P according to opening and closing of the gripper G, winding the belt B to lift the gripper, and starting traveling. However, in this way, the waiting time of the transfer vehicle A is long, so that the operation efficiency of the transfer vehicle AP is reduced.

[0006] To solve this problem, as Figure 2As shown, a method in which the belt B is wound or unwound while the transport carrier A travels can be considered. In this case, the advantage is that the waiting time of the transport carrier A can be shortened, so that the operation efficiency of the transport carrier A can be increased. However, in this method, since the transport carrier A travels in a state in which the length of the belt B increases, the position of the gripper G connected to the belt B can greatly change. For example, Figure 3 The change in the position x of the transport carrier A with time t, the change in the speed v of the transport carrier A with time t, and the change in the length l of the belt B with time t, and the change in the angle Θ of the belt B with time t are shown. The angle Θ of the belt B means the angle between an axis perpendicular to the floor and the belt B. As shown, Figure 3 As shown, it can be seen that when the length l of the belt B changes from t2 to t3, which is a section in which the transport carrier A accelerates and decelerates, the angle Θ of the belt B significantly changes. In this case, the gripper G connected to the belt B also greatly shakes. In addition, when the gripper G holds the container F, impurities such as particles are generated in the container F, thereby contaminating the article such as a substrate or damaging the article. SUMMARY

[0007] The present application is proposed in order to provide a transport unit, an article transport system, and a control method of a transport unit, which can stably transport an article.

[0008] The present application is also proposed in order to provide a transport unit, an article transport system, and a control method of a transport unit, which can minimize vibrations generated in an article or a container in which an article is accommodated.

[0009] The present application is also proposed in order to provide a transport unit, an article transport system, and a control method of a transport unit, which can shorten the time of transporting an article or a container in which an article is accommodated.

[0010] The objects of the present application are not limited to the above, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

[0011] An exemplary embodiment of the present invention provides a transport unit traveling on a track disposed along a ceiling, the transport unit including a main body provided with a travel driver, a travel wheel rotating by receiving power from the travel driver, a clamping member configured to clamp an article, a lifting member disposed between the main body and the clamping member and configured to move the clamping member in a vertical direction, and a controller, wherein the controller is configured to control the lifting member and the travel driver to lower or raise the clamping member while the transport unit travels on the track, and the controller controls the lifting member and the travel driver such that lowering or raising of the clamping member is performed in a constant speed section in which the transport unit travels at a constant speed.

[0012] According to an exemplary embodiment, the lifting member can include a belt connected with the clamping member, and a lifting driver winding or unwinding the belt.

[0013] According to an exemplary embodiment, the controller can control the travel driver and the lifting driver such that a length of the belt is fixed in an acceleration section or in a deceleration section.

[0014] According to an exemplary embodiment, the controller can control the travel driver such that a shake attenuation operation attenuating a shake of the article clamped by the clamping member is performed in an acceleration section in which a travel speed of the transport unit increases or in a deceleration section in which the travel speed of the transport unit decreases.

[0015] According to an exemplary embodiment, the shake attenuation operation can be an operation of changing a travel acceleration of the transport unit in a half period of a shake cycle of the article.

[0016] According to an exemplary embodiment, the shake attenuation operation can be an operation of changing the travel acceleration of the transport unit from a first acceleration to a second acceleration smaller than the first acceleration.

[0017] According to an exemplary embodiment, the shake attenuation operation can be an operation of changing the travel of the transport unit from a first accelerated travel at the first acceleration to constant speed travel and changing the travel of the transport unit from the constant speed travel to a second accelerated travel at the second acceleration.

[0018] According to an exemplary embodiment, a time during which the transport unit performs the constant speed travel can be shorter than a time during which the transport unit performs the first accelerated travel or the second accelerated travel.

[0019] Another exemplary embodiment of the present invention provides an article conveying system for conveying a container containing an article along a ceiling of a production line in which semiconductor processing apparatuses are continuously arranged, the article conveying system including: a track arranged along the ceiling; a port configured to allow the container to be placed; a conveying unit traveling along the track and configured to convey the container to the port, wherein the conveying unit includes: a main body provided with a traveling driver; a gripping member configured to grip the container; a lifting member arranged between the main body and the gripping member and configured to move the gripping member in a vertical direction; and a controller, wherein the controller is configured to control the lifting member and the traveling driver to lower or raise the gripping member as the conveying unit travels on the track, and the controller controls the lifting member and the traveling driver such that the lowering or raising of the gripping member is performed in a constant speed section in which the conveying unit travels at a constant speed.

[0020] According to an exemplary embodiment, the lifting member can include a belt connected with the gripping member, and a lifting driver that changes a length of the belt by winding or unwinding the belt.

[0021] According to an exemplary embodiment, the controller can control the traveling driver and the lifting driver such that the length of the belt is fixed in an acceleration section in which a traveling speed of the conveying unit increases and in a deceleration section in which the traveling speed of the conveying unit decreases.

[0022] According to an exemplary embodiment, the controller can control the traveling driver such that a sway damping operation that attenuates sway of the article gripped by the gripping member is performed in an acceleration section in which a traveling speed of the conveying unit increases or in a deceleration section in which the traveling speed of the conveying unit decreases.

[0023] According to an exemplary embodiment, the sway damping operation can be an operation that changes a traveling acceleration of the conveying unit in a half period of a sway cycle of the article.

[0024] According to an exemplary embodiment, the sway damping operation can be an operation that changes the traveling acceleration of the conveying unit from a first acceleration to a second acceleration smaller than the first acceleration.

[0025] According to an example embodiment, the shake attenuation operation can be an operation of changing the travel of the transport unit from a first accelerated travel at the first acceleration to a constant speed travel and changing the travel of the transport unit from the constant speed travel to a second accelerated travel at the second acceleration.

[0026] According to an example embodiment, a time during which the transport unit performs the constant speed travel can be shorter than a time during which the transport unit performs the first accelerated travel or the second accelerated travel.

[0027] Yet another embodiment of the present invention provides a method of controlling a transport unit that travels on a track provided along a ceiling of a semiconductor production line and transports a container that houses a substrate, the transport unit including a travel wheel that travels on the track, a travel driver that transmits power to the travel wheel, a clamping member that clamps the container, a belt that is connected to the clamping member, and a lift driver that changes a length of the belt by winding or unwinding the belt, the method including controlling the lift driver to change the length of the belt in a constant speed section in which the transport unit travels at a constant speed among a constant speed section in which the transport unit travels at a constant speed, an acceleration section in which a travel speed of the transport unit increases, and a deceleration section in which the travel speed of the transport unit decreases.

[0028] According to an example embodiment, the lift driver can be controlled so that the length of the belt is fixed in the acceleration section and the deceleration section.

[0029] According to an example embodiment, the travel driver can be controlled to perform a shake attenuation operation that attenuates a shake of the article clamped by the clamping member in the acceleration section or in the deceleration section.

[0030] According to an example embodiment, the shake attenuation operation can be an operation of changing an acceleration of the travel of the transport unit in a half period of a shake cycle of the article.

[0031] Yet another exemplary embodiment of the present application provides a method of controlling a transport unit to cause the transport unit to perform operations, the transport unit traveling on a track provided along a ceiling of a semiconductor production line and transporting a container in which a substrate is accommodated, the transport unit including a traveling wheel traveling on the track, a traveling driver for delivering power to the traveling wheel, a clamping member for clamping the container, and a lifting driver for changing a height of the clamping member, the operations including lowering the clamping member before the transport unit reaches an upper portion of a port in which the container is placed, moving the transport unit to the upper portion of the port while the height of the clamping member is fixed, and loading or unloading the container to or from the port by the clamping member.

[0032] According to an exemplary embodiment, the operations further include moving the transport unit away from the upper portion of the port while the height of the clamping member is fixed, and raising the clamping member after the transport unit moves away from the upper portion of the port.

[0033] According to an exemplary embodiment, the lowering of the clamping member or the raising of the clamping member can be performed while the transport unit travels.

[0034] According to an exemplary embodiment, the lowering of the clamping member or the raising of the clamping member can be performed while the transport unit travels at a constant speed.

[0035] According to an exemplary embodiment, a speed of the transport unit can be changed while the height of the clamping member is fixed.

[0036] According to an exemplary embodiment, an article can be stably transported.

[0037] Further, according to an exemplary embodiment of the present application, vibration generated in an article or a container in which an article is accommodated can be minimized.

[0038] Further, according to an exemplary embodiment of the present application, a time for transporting an article or a container in which an article is accommodated can be shortened.

[0039] Effects of the present application are not limited to the above-mentioned effects and a person skilled in the art can clearly understand other unmentioned effects from the present specification and the attached drawings. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 is a diagram showing a method in which a transport vehicle in the related art transports a container to a port.

[0041] Figure 2 is a graph showing an improved method in which the transport carrier transports the container to the port.

[0042] Figure 3 is a graph showing Figure 2 a change in position of the transport carrier, a change in speed of the transport carrier, a change in length of the belt of the transport carrier, and a change in angle of the belt of the transport carrier.

[0043] Figure 4 is a graph schematically showing a state of the semiconductor production line as viewed from above.

[0044] Figure 5 is a graph showing a transport unit traveling on a track of Figure 4 as viewed from the front.

[0045] Figure 6 is a graph showing a transport unit traveling on a track of Figure 4 as viewed from the side.

[0046] Figure 7 is a graph showing a transport unit traveling on a track of Figure 4 as viewed from above.

[0047] Figure 8 is a graph showing a case where the transport unit of the present application travels while maintaining a traveling direction in a branch region as viewed from above.

[0048] Figure 9 is a graph showing a case where the transport unit of the present application travels while changing a traveling direction in a branch region as viewed from above.

[0049] Figure 10 is a graph showing a state where the transport unit of the present application transports a container in which an article is accommodated.

[0050] Figure 11 is a graph showing a change in rotational speed of a traveling driver for rotating a traveling wheel and a change in rotational speed of a lifting driver for winding or unwinding a belt according to the present application.

[0051] Figure 12 is a graph showing a change in position of the transport unit, a change in speed of the transport unit, a change in length of the belt of the transport unit, and a change in angle of the belt of the transport unit according to the present application.

[0052] Figure 13 , Figure 14 and Figure 15 are graphs showing a change in angle of the belt for describing a sway damping operation of Figure 11 . DETAILED DESCRIPTION

[0053] Hereinafter, exemplary embodiments of the present application will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the application are shown. The application may, however, be embodied in different ways and is not limited to the embodiments below. In the following description of the present application, detailed descriptions of known functions and configurations incorporated herein are omitted to avoid making the subject matter of the present application unclear. Furthermore, for portions having similar functions and operations, the same reference numerals are used throughout the drawings.

[0054] Unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. It will be understood that the terms "comprise" and "have" are intended to denote the presence of the feature, number, step, operation, component, and parts or combinations thereof described in the specification, but do not preclude the possibility of additional one or more other features, numbers, steps, operations, components, and parts or combinations thereof.

[0055] The singular expression used herein includes the plural expression unless they have a clearly opposite meaning in the context. Therefore, for a clearer description, the shape, size, etc. of the elements in the drawings can be exaggerated.

[0056] Terms such as first and second are used to describe various constituent elements, but the constituent elements are not limited by the terms. The terms are merely used to distinguish one constituent element from another. For example, without departing from the scope of the present application, a first constituent element can be called a second constituent element, and similarly, a second constituent element can be called a first constituent element.

[0057] It should be understood that when one constituent element is referred to as "coupled" or "connected" to another constituent element, the one constituent element can be directly coupled or connected to the other constituent element, but there can also be an intermediate element. In contrast, when one constituent element is "directly coupled" or "directly connected" to another constituent element, it should be understood that there is no intermediate element. Other expressions describing the relationship between constituent elements, such as "between" and "directly between" or "adjacent" and "directly adjacent", should be similarly interpreted.

[0058] All terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art, unless they are differently defined. Terms defined in commonly used dictionaries should be interpreted as having a meaning that matches those in the context of related technology, and should not be interpreted in an idealized or overly formal sense, unless they are clearly defined in the present application.

[0059] The article transfer system of the present exemplary embodiment can be used to transfer containers. In particular, the article transfer system of the present exemplary embodiment transfers containers that contain articles. The articles can be substrates such as wafers, glass, or reticles. The containers that contain the articles can be front opening unified pods (FOUPs) or tape cassettes. Further, the containers that contain the articles can be PODs. In addition, the containers that contain the articles can include cassettes for containing a plurality of printed circuit boards, trays for containing a plurality of semiconductor packages, and the like.

[0060] Hereinafter, a case where the article transfer system transfers containers that contain substrates such as wafers to semiconductor processing apparatuses provided in a semiconductor production line will be described as an example. The articles transferred by the article transfer apparatus will be described based on substrates for manufacturing semiconductor elements as an example. However, the present application is not limited thereto, and the article transfer apparatus of the present exemplary embodiment can be equally or similarly applied to various production lines that require transfer of articles and / or containers that contain the articles.

[0061] Hereinafter, a case where the article transfer system transfers containers that contain substrates such as wafers to semiconductor processing apparatuses provided in a semiconductor production line will be described as an example. The articles transferred by the article transfer apparatus will be described based on substrates for manufacturing semiconductor elements as an example. However, the present application is not limited thereto, and the article transfer apparatus of the present exemplary embodiment can be equally or similarly applied to various production lines that require transfer of articles and / or containers that contain the articles. Figures 4 to 15 An exemplary embodiment of the present application will be described in detail.

[0062] Figure 4 is a diagram schematically showing a state of a semiconductor production line viewed from above. With reference to Figure 4 The article transfer system 1000 according to the present application can transfer containers 20 that contain articles to a semiconductor production line in which semiconductor processing apparatuses 10 are continuously arranged. The article transfer system 1000 can include a track 300, a transfer unit 500, and a port P which will be described later. The port P can be a load port included in the semiconductor manufacturing apparatus 10 and on which the container 20 is placed. Alternatively, the port P can be a port included in a container storage apparatus (not shown) for storing the container 20. Alternatively, the port P can be a buffer frame installed on a ceiling of the semiconductor production line.

[0063] The track 300 provides a path along which the transfer unit 500 which will be described later travels. The track 300 can include a travel track 310 and a turning track 330. The track 300 can be fixedly installed on a ceiling of the semiconductor production line.

[0064] The transfer unit 500 can be referred to as a carrier or a transfer carrier. The transfer unit 500 can be an overhead hoist device. The transfer unit 500 can grip the container 20. The transfer unit 500 can travel on a predetermined path along the track 300.

[0065] In Figure 4In the middle, the track 300 is shown in a substantially hexagonal shape, but the shape of the track 300 can be variously modified, such as a circular shape or a square shape. The track 300 is disposed along the ceiling of the semiconductor production line and can be installed so that the semiconductor processing apparatus 10 can be inspected from above. The installation range of the track 300 can be arranged in a wide area so that the entire semiconductor processing apparatus 10 can be seen.

[0066] Figure 5 is a view showing a transfer unit traveling on a track of Figure 4 from the front, Figure 6 is a view showing a transfer unit traveling on a track of Figure 4 from the side, and Figure 7 is a view showing a transfer unit traveling on a track of Figure 4 from above.

[0067] Referring to Figures 5 to 7 As described above, the article transfer system 1000 can include a track 300 and a transfer unit 500.

[0068] The track 300 can include a travel track 310 and a turning track 330.

[0069] The travel track 310 can provide a travel path along which the transfer unit 500 to be described later travels. The travel wheels 520 of the transfer unit 500 to be described later can be in contact with the travel track 310. The travel track 310 can be provided in plurality and can be disposed to be spaced apart from each other. For example, the travel track 310 can be provided as a pair. The pair of travel tracks 310 can be parallel to each other and can be disposed at the same height.

[0070] The turning track 330 can change the travel direction of the transfer unit 500 to be described later. The turning track 330 can be in contact with the turning wheels 532 of the transfer unit 500 to be described later. The turning track 330 can include a straight branch track 332 and a curved branch track 334. The straight branch track 332 can maintain the travel path of the transfer unit 500 in a region where the travel track 310 branches. In addition, the curved branch track 334 can maintain the travel path of the transfer unit 500 in a region where the travel track 310 branches.

[0071] The transfer unit 500 can travel on the track 300. The transfer unit 500 can travel on the travel track 310. The transfer unit 500 can grip the container 20. The transfer unit 500 can travel on the track 300 while gripping the container 20. The transfer unit 500 can include a main body 510, travel wheels 520, a turning member 530, a frame 540, a neck 550, a slider 560, a lifting member 570, a gripping member 580, and a controller 590.

[0072] The traveling wheels 520, the steering member 530, and the neck portion 550 can be coupled to the main body 510. The traveling wheels 520 can be rotatably coupled to the main body 510. In addition, the main body 510 can be provided with a traveling driver 511 for rotating the traveling wheels 520. In addition, the main body 510 can be provided with a controller 590 that controls the operation of the transport unit 500. Also, the steering member 530 can be provided on the upper surface of the main body 510. In addition, the neck portion 550 can be rotatably coupled to the main body 510.

[0073] The traveling driver 511 can transmit power to the traveling wheels 520 to rotate the traveling wheels 520. In addition, a plurality of main bodies 510 can be provided. Each main body 510 can have the aforementioned traveling driver 511. In addition, the aforementioned driving wheels 520, the steering member 530, and the neck portion 550 can be coupled to each main body 510.

[0074] The traveling wheels 520 can be rotatably coupled to the main body 510. The traveling wheels 520 can be rotated by receiving power from the traveling driver 511. The traveling wheels 520 can be rotated while being in contact with the rail 300. The traveling wheels 520 can be coupled to the main body 510. The traveling wheels 520 can be rotatably coupled to the main body 510. The traveling wheels 520 can be in contact with the traveling rail 310 in the rail 300, and can be rotated to travel on the traveling rail 310. A plurality of traveling wheels 520 can be provided. The driving wheels 520 can be provided as a pair. One of the traveling wheels 520 can be rotatably coupled to one surface of the main body 510, and the other of the traveling wheels 520 can be rotatably coupled to the other surface opposite to the one surface of the main body 510.

[0075] The steering member 530 can be provided above the main body 510. The steering member 530 can include a plurality of steering wheels 532 and a steering rail 534. When viewed from above, the steering wheels 532 can be provided in a direction parallel to the traveling direction of the transport unit 500. In addition, when viewed from above, the longitudinal direction of the steering rail 534 can be parallel to a direction perpendicular to the traveling direction of the transport unit 500. Also, the position of the steering wheels 532 can vary along the longitudinal direction of the steering rail 534.

[0076] The frame 540 can have an internal space. The slider 560, the lifting member 570, and the clamping member 580, which will be described later, can be disposed in the internal space of the frame 540. In addition, the frame 540 can have a hexahedral shape in which both the lateral surface and the lower surface are open. That is, the front surface and the rear surface of the frame 540 can be provided as a baffle. Accordingly, it is possible to prevent the container 20 held by air resistance from shaking while the transport unit 500 travels. In addition, the frame 540 can be coupled to the body 510 via the neck 550. The neck 550 can be rotatably disposed with respect to the body 510 and the frame 540. The frame 540 can be coupled to at least one body 510 via at least one neck 550. For example, one frame 540 can be provided, and two necks 550 can be coupled to one frame 540. In addition, two necks 550 can be respectively coupled to different bodies 510, respectively.

[0077] The slider 560 can be coupled to the frame 540. The slider 560 can be coupled such that the position of the slider 560 with respect to the frame 540 can be changed. The slider 560 can be disposed in the internal space of the frame 540 and can be coupled to the lower surface of the frame 540. The slider 560 can be coupled to the frame 540 so as to change the position of the slider 560 to the left and the right with respect to the traveling direction of the transport unit 500. Also, the slider 560 can be coupled to the lifting member 570, which will be described later. Accordingly, the position of the lifting member 570 can be changed by changing the position of the slider 560.

[0078] The lifting member 570 can be disposed between the body 510 and the clamping member 580. The lifting member 570 can move the clamping member 580 in the vertical direction. The lifting member 570 can raise or lower the clamping member 580. The lifting member 570 can include a lifting driver 571 and a belt 572. The lifting member 570 can be referred to as a hoisting device. The lifting driver 571 can change the length of the suspended belt 572 by winding or unwinding the belt 572. For example, the length of the belt 572 can increase when the lifting driver 571 unwinds the belt 572, and the length of the belt 572 can be shortened when the lifting driver 571 winds the belt 572. In addition, a plurality of belts 572 can be provided. One end of each of the plurality of belts 572 can be connected to the clamping member 580.

[0079] The clamping member 580 can clamp the container 20. When the clamping member 580 is closed, the clamping member 580 can clamp the container 20. When the clamping member 580 is opened, the clamping member 580 can release the container 20. That is, the clamping member 580 can detachably clamp the container 20. The clamping member 580 can unload the container 20 from a port P, such as a load port of a semiconductor processing apparatus.

[0080] The controller 590 can be provided in the main body 510, as described above. The controller 590 can be provided in the internal space of the main body 510. The controller 590 can control at least one of the components of the conveying unit 500, for example, the traveling driver 511, the lifting driver 571, and the slider 560. In addition, the controller 590 can generate a control signal for performing the control method of the conveying unit 500, which will be described below.

[0081] Figure 8 is a view illustrating a case in which the conveying unit of the present application travels while maintaining a traveling direction in a branching region, viewed from above. Referring to Figure 8 When the conveying unit 500 travels while maintaining the traveling direction in the branching region, the turning wheel 532 of the turning member 530 moves to a position in contact with the straight branching track 332. Accordingly, in the branching region, the traveling wheel 520 is in contact with any one of the traveling tracks 310, the turning wheel 532 is in contact with the straight branching track 332, and the traveling direction of the conveying unit 500 is maintained.

[0082] Figure 9 is a view illustrating a case in which the conveying unit of the present application travels while changing a traveling direction in a branching region, viewed from above. Referring to Figure 9 When the conveying unit 500 travels while changing the traveling direction in the branching region, the turning wheel 532 of the turning member 530 moves to a position in contact with the curved branching track 334. Accordingly, in the branching region, the traveling wheel 520 is in contact with any one of the traveling tracks 310, the turning wheel 532 is in contact with the curved branching track 334, and the traveling direction of the conveying unit 500 is changed.

[0083] Hereinafter, a method of controlling the conveying unit 500 according to an exemplary embodiment of the present application, more specifically, a control method of the conveying unit 500 for performing the article conveying method, will be described in detail.

[0084] Figure 10 is a view illustrating a state in which the conveying unit of the present application conveys a container in which an article is accommodated. In Figure 10 In, AP denotes a traveling path of the conveying unit 500. GP denotes a moving path of the gripping member 570. Referring to Figure 10, the conveying unit 500 can convey the container 20 containing the article to the port P. The conveying unit 500 can move along the travel rail 310 to convey the container 20 to the port P. For example, before the conveying unit 500 reaches the upper portion of the port P where the container 20 is placed, the lifting drive 571 can lower the clamping member 580. When the lowering of the clamping member 580 is completed, the height of the clamping member 580 can be fixed. When the height of the clamping member 580 is fixed, the conveying unit 500 can move to the upper portion of the port P. Thereafter, the clamping member 580 can load the container 20 into the port P or unload the container 20 from the port P. Figure 10 The figure shows the operation of the conveyor unit 500 loading the container 20 into the port P. For example, when the conveyor unit 500 stops at the upper portion of the port P, the gripping member 580 can be opened. When the gripping member 580 completes the operation of loading or unloading the container 20, the conveyor unit 500 can begin to move forward. At this time, the conveyor unit 500 can leave the upper portion of the port P, while the height of the gripping member 580 is fixed. After the conveyor unit 500 leaves the upper portion of the port P, the gripping member 580 can move upward.

[0085] The height of the gripping member 580 can be changed by the elevating driver 571. Furthermore, the operation of changing the height of the gripping member 580 (that is, the operation of the elevating driver 571 winding or unwinding the belt 572 to lower or raise the gripping member 280) can be performed while the conveyor unit 500 is traveling. Since the height control of the gripping member 580 is performed while the conveyor unit 500 is traveling, the waiting time (e.g., the stop time) of the conveyor unit 500 can be shortened. Consequently, the time it takes for the conveyor unit 500 to convey an article or a container 20 containing an article can be shortened.

[0086] Figure 11 is a graph showing the rotational speed of a travel drive for rotating a travel wheel and the rotational speed of a lifting drive for winding or unwinding a belt according to the present invention, and Figure 12 is a graph showing a position change of a conveying unit, a speed change of a conveying unit, a belt length change of a conveying unit, and a belt angle change of a conveying unit according to the present invention.

[0087] although Figure 11 VP1 in FIG. 5 represents the rotation speed of the travel driver 511 , but VP1 may represent the travel speed of the conveyor unit 500 . VP2 in FIG. 5 represents the rotation speed of the elevating driver 571 , but VP2 may represent the length change speed of the belt 572 .

[0088] Figure 12The change in the position x of the conveyance unit 500 with time t, and the change in the speed v of the conveyance unit 500, the change in the length l of the belt 572 of the conveyance unit 500, and the change in the angle Θ of the belt 572 of the conveyance unit 500 can be represented. The angle Θ can mean the angle between the longitudinal axis of the belt 572 and the axis perpendicular to the ground.

[0089] As shown in FIG. 10, the travel of the conveyance unit 500 can have an acceleration section S10, a constant speed section S20, and a deceleration section S30. The acceleration section S10 (t0 to t3) can be a section in which the travel speed of the conveyance unit 500 increases. The constant speed section S20 (t3 to t6) can be a section in which the conveyance unit 500 travels at a constant speed. The deceleration section S30 (t6 to t9) can be a section in which the travel speed of the conveyance unit 500 decreases. The constant speed section S20 can be a section between the acceleration section S10 and the deceleration section S30. Figure 11 Figure 12 As shown in FIG. 10, the travel of the conveyance unit 500 can have an acceleration section S10, a constant speed section S20, and a deceleration section S30. The acceleration section S10 (t0 to t3) can be a section in which the travel speed of the conveyance unit 500 increases. The constant speed section S20 (t3 to t6) can be a section in which the conveyance unit 500 travels at a constant speed. The deceleration section S30 (t6 to t9) can be a section in which the travel speed of the conveyance unit 500 decreases. The constant speed section S20 can be a section between the acceleration section S10 and the deceleration section S30.

[0090] In the acceleration section S10 or the deceleration section S30, the conveyance unit 500 can perform a sway attenuation operation to attenuate the sway of the container 20 gripped by the gripping member 580. The sway attenuation operation can be performed by changing the travel speed of the conveyance unit 500. For example, the sway attenuation operation can be an operation of changing the magnitude of the acceleration of the conveyance unit 500 in half of the sway period of the container 20 that accommodates an article such as a substrate.

[0091] The sway period can be a period in which the container 20 sways when the conveyance unit 500 that is stopped starts to travel at t0. In addition, the sway period can be a period in which the container 20 sways when the conveyance unit 500 that travels at a constant speed starts to decelerate at t6.

[0092] The sway attenuation operation can be an operation of changing the travel acceleration of the conveyance unit 500 from a first acceleration to a second acceleration that is smaller than the first acceleration. For example, the sway attenuation operation can be an operation of changing the travel of the conveyance unit from first accelerated travel (t0 to t1 or t6 to t7) at the first acceleration to constant speed travel (t1 to t2 or t7 to t8) and changing the travel of the conveyance unit from the constant speed travel (t1 to t2 or t7 to t8) to second accelerated travel (t2 to t3 or t8 to t9) at the second acceleration. In addition, the time (t1 to t2 or t7 to t8) in which the conveyance unit 500 travels at a constant speed can be much shorter than the time in which the conveyance unit 500 performs the first accelerated travel (t0 to t1 or t6 to t7) and / or the second accelerated travel (t2 to t3 or t8 to t9).

[0093] Hereinafter, the sway attenuation operation of the present application will be described in more detail with reference to Figures 13 to 15 Figure 13 ​​The change in the angle θ of the belt 572 when the shaking attenuation operation of the present application is not performed is shown. As shown in Figure 13 , when the conveyance unit 500 accelerates / decelerates, the angle θ of the belt 572 changes to a waveform A having one cycle T c due to inertia. In general, an operation such as clamping the container 20 should be performed after waiting until the change in the angle θ of the belt 572 stabilizes (that is, the vibration is eliminated). However, as shown in Figure 14 , when a shaking of a smaller size is generated after a half cycle (1 / 2T c ) of the waveform B of the same event, only a waveform R as shown in Figure 15 remains. That is, the shaking attenuation operation of the present application can minimize the shaking that occurs in the container 20 by the following method: in the acceleration section S10 or the deceleration section S30, after the event (the start of acceleration or the start of deceleration) that causes the shaking in the container 20, a shaking of the same cycle is again generated in the container 20 after a half cycle (1 / 2T c ) of the shaking cycle that occurs in the container 20 (the acceleration is again started after traveling at a constant speed from tl to t2, or the deceleration is again started after traveling at a constant speed from t7 to t8).

[0094] Referring again to Figure 11 and Figure 12 , in this shaking attenuation operation, the size of the traveling acceleration of the conveyance unit 500 can be changed in a half cycle (1 / 2T c ) of the shaking cycle of the container 20. For example, the operation of changing the size of the traveling acceleration can be an operation in which the size of the traveling acceleration of the conveyance unit 500 is changed from a first acceleration at tl or t7 to 0 and to a second acceleration after t2 or t8. The second acceleration can be a speed smaller than the first acceleration. Furthermore, the interval t0 to tl can be greater than the interval t2 to t3. Also, the interval t6 to t7 can be greater than t8 to t9.

[0095] Also, in the belt 572, the length l of the belt 572 can be fixed in the acceleration section S10 and / or the deceleration section S30. That is, the distance from the main body 510 to the clamping member 580 can be fixed in the acceleration section S10 and / or the deceleration section S30.

[0096] The length l of the belt 572 can be changed in the constant speed section S20. In other words, the raising or lowering of the clamping member 580 can be performed in the constant speed section S20. In the constant speed section S20, since the resultant force transmitted to the components of the conveyance unit 500 is 0, even if the length l of the belt 572 (the height of the clamping member 580 is changed), the occurrence of shaking can be suppressed as much as possible.

[0097] In addition, when the length l of the belt 572 is changed in the acceleration section S10 and / or the deceleration section S30, the oscillation period of the clamping member 580, which is a parameter of the aforementioned vibration damping operation, changes, so that the rocking is not suppressed. Therefore, in the control method of the conveying unit 500 according to the example embodiment of the present application, the length l of the belt 572 is fixed in the acceleration section S10 and the deceleration section S30, and the length l of the belt 572 is changed in the constant speed section S20 in which the vibration damping operation is not required, whereby the occurrence of the aforementioned problem is minimized.

[0098] In the foregoing example, although the case where the length l of the belt 572 is changed in the constant speed section S20 in the section in which the conveying unit 500 travels has been described as an example, the present application is not limited thereto. For example, when the slider 560 of the conveying unit 500 moves the lifting member 570, the travel of the lifting member 560 of the conveying unit 500 can have an acceleration section, a constant speed section, and a deceleration section. In this case, the length of the belt 572 can be changed in the constant speed section among the sections in which the conveying unit 500 travels.

[0099] In the foregoing example, the case where the article conveying system 1000 is applied to a semiconductor production line has been described as an example, but the present application is not limited thereto. For example, the article conveying system 1000 can be equally or similarly applied to various production lines in which articles need to be conveyed.

[0100] The foregoing detailed description shows the present application. Furthermore, the foregoing shows and describes example embodiments of the present application, and the present application can be used in various other combinations, modifications, and environments. That is, the foregoing can be modified or corrected within the scope of the inventive concept disclosed in the present specification, the scope equivalent to the present disclosure, and / or the scope of the knowledge of those skilled in the art. The foregoing example embodiments describe the best state for implementing the technical spirit of the present application, and various changes required by the specific application field and use of the present application are possible. Therefore, the foregoing detailed description of the present application is not intended to limit the present application to the disclosed example embodiments. Furthermore, the appended claims should be interpreted as also including other example embodiments.

Claims

1. A substrate transport system for transporting a container containing a substrate along a ceiling of a semiconductor production line on which semiconductor processing apparatuses are continuously provided, the substrate transport system comprising: a track provided along the ceiling; a port configured to allow the container to be placed; a transport unit that travels along the track and is configured to transport the container to the port, wherein the transport unit includes: a main body provided with a travel driver; a travel wheel that rotates by receiving power from the travel driver; a clamping member configured to clamp the container and configured to load or unload the container to or from the port; a lifting member provided between the main body and the clamping member and configured to move the clamping member in a vertical direction; and a controller, and wherein the controller is configured to control the lifting member and the travel driver: to lower or raise the clamping member in a constant speed section in which the transport unit travels at a constant speed while the transport unit travels on the track; to fix a height of the clamping member in an acceleration section in which a travel speed of the transport unit increases and in a deceleration section in which the travel speed of the transport unit decreases; and to perform a sway damping operation that attenuates a sway of the container clamped by the clamping member in the acceleration section or in the deceleration section.

2. The substrate transport system according to claim 1, wherein the lifting member includes: a belt connected with the clamping member; and a lifting driver that changes a length of the belt by winding or unwinding the belt.

3. The substrate transport system according to claim 1, wherein the sway damping operation is an operation that changes a travel acceleration of the transport unit in a half period of a sway cycle of the substrate.

4. The substrate transport system according to claim 3, wherein the sway damping operation is an operation that changes the travel acceleration of the transport unit from a first acceleration to a second acceleration smaller than the first acceleration.

5. The substrate transport system according to claim 4, wherein the sway damping operation is an operation that changes the travel of the transport unit from a first accelerated travel at the first acceleration to a constant speed travel and changes the travel of the transport unit from the constant speed travel to a second accelerated travel at the second acceleration.

6. The substrate transport system according to claim 5, wherein a time during which the transport unit performs the constant speed travel is shorter than a time during which the transport unit performs the first accelerated travel or the second accelerated travel. a travel wheel that travels on the track; 7. A method of controlling a transport unit that travels on a track provided along a ceiling of a semiconductor production line and transports a container that houses a substrate, the transport unit comprising: a travel driver for transmitting power to the travel wheel; a clamping member for clamping the container; a belt connected with the clamping member; ​ and a lifting drive for changing a length of the belt by winding or unwinding the belt, the method comprising: controlling the lifting drive and the travel drive to change the length of the belt in constant speed segments in which the conveying unit travels along the track at a constant speed, to fix the length of the belt in acceleration segments in which a travel speed of the conveying unit increases and in deceleration segments in which the travel speed of the conveying unit decreases, and to perform a sway damping operation that attenuates a sway of the container held by the holding member in the acceleration segments or in the deceleration segments.

8. The method according to claim 7, wherein the sway damping operation is an operation that changes a travel acceleration of the conveying unit in a half period of a sway cycle of the substrate.

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