Patent ID: 12217553

While various embodiments are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the claimed inventions to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the claims.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention are described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below and is implemented in various other forms. Embodiments below are not provided to fully complete the present invention but rather are provided to fully convey the range of the present invention to those skilled in the art.

In the specification, when one component is referred to as being on or connected to another component or layer, it can be directly on or connected to the other component or layer, or an intervening component or layer may also be present.

Unlike this, it will be understood that when one component is referred to as directly being on or directly connected to another component or layer, it means that no intervening component is present. Also, though terms like a first, a second, and a third are used to describe various regions and layers in various embodiments of the present invention, the regions and the layers are not limited to these terms.

Terminologies used below are used to merely describe specific embodiments, but do not limit the present invention. Additionally, unless otherwise defined here, all the terms including technical or scientific terms, may have the same meaning that is generally understood by those skilled in the art.

Embodiments of the present invention are described with reference to schematic drawings of ideal embodiments. Accordingly, changes in manufacturing methods and/or allowable errors may be expected from the forms of the drawings. Accordingly, embodiments of the present invention are not described being limited to the specific forms or areas in the drawings, and include the deviations of the forms. The areas may be entirely schematic, and their forms may not describe or depict accurate forms or structures in any given area, and are not intended to limit the scope of the present invention.

FIG.1is a block diagram illustrating a material transport apparatus in accordance with an embodiment of the present invention,FIG.2is a schematic view illustrating a transport vehicle as shown inFIG.1, andFIG.3is a schematic view illustrating a dog bar mounted on a slide unit and a home sensor mounted on a frame unit as shown inFIG.2.

Referring toFIGS.1and2, a material transport apparatus400, in accordance with an embodiment of the present invention, may include a transport vehicle100configured to be movable along a transport rail10and configured to transport a material20, a control unit200for controlling a movement operation of the transport vehicle100and loading and unloading operations of the material20, and an abnormality prediction unit300for predicting whether an abnormality will occur in the transport vehicle100. For example, the transport vehicle100may transport a material20such as a cassette for accommodating semiconductor substrates, a magazine for accommodating printed circuit boards or lead frames, and a reticle pod for accommodating a reticle.

The transport vehicle100may include a drive unit110, a frame unit120, a slide unit130, a hoist unit140, and a hand unit150.

For example, a pair of drive units110may be disposed on the transport rail10, and the frame unit120may be connected to lower portions of the drive units110. Each of the drive units110may include drive wheels111and a drive motor (not shown) for rotating the drive wheels111. The frame unit120may have a space for accommodating the material20, and a lower portion of the frame unit120may be opened for vertical movement of the material20. Further, one side or both sides of the frame unit120may be opened for horizontal movement of the material20.

The slide unit130may be disposed in the frame unit120, and the slide unit130may be configured to be movable in a horizontal direction perpendicular to a moving direction of the drive units110through the open side portions of the frame unit120.

The transport vehicle100may include a dog bar131and a home sensor133for detecting a home position of the slide unit130. The dog bar131may be mounted on the slide unit130, and the home sensor133may be mounted on the frame unit120to detect the dog bar131. The dog bar131may have a predetermined length in the horizontal direction, and the home sensor133may be disposed above the dog bar131in order to detect the dog bar131.

The hoist unit140may move the hand unit150in a vertical direction using a belt141, and the hand unit150may include a gripper for gripping the material20. The hoist unit140may be mounted on a lower portion of the slide unit130, and may be moved in the horizontal direction by the slide unit130. Further, although not shown, the hoist unit140or the hand unit150may be configured to be rotatable.

In addition, although not shown in figures, the transport vehicle100may include an obstacle sensor and a front distance sensor mounted on the frame unit120, sensors for detecting a movement operation of the transport vehicle100and loading and unloading operations of the material20, a position sensor for detecting a position of the transport vehicle100on the transport rail10, and a code reader for detecting a barcode or QR code attached to the transport rail10.

In accordance with an embodiment of the present invention, the transport vehicle100may include a data acquisition section160, a determination section170, a self-correction section180, and a first communication section190.

The data acquisition section160may acquire operation data on the movement operation and the loading and unloading operations of the transport vehicle100. For example, the operation data may be acquired from the sensors, and the data acquisition section160may generate a log file related to the movement operation and the loading and unloading operations.

Specifically, the operation data on the movement operation may be data on an operation of the drive unit110of the transport vehicle100. The operation data on the loading and unloading operations may be data on operations of the slide unit130, the hoist unit140, and the hand unit150of the transport vehicle100.

The operation data may include a home position and left and right limit adjustment state of the slide unit130, a deviation between a home position of the hoist unit140and a position of the hoist unit140, an operation time and sensor detection state of the hand unit150, a distortion and input/output of an obstacle sensor and a front distance sensor mounted on the frame unit120, and a sensing distance of the sensors for a movement of the drive unit110and loading and unloading of the material20, a recognition rate of barcode or QR code of a code reader mounted on the frame unit120, and a wear state of drive wheels111of the drive unit110.

The determination section170may determine whether there is an abnormality in the movement operation and the loading and unloading operations on the basis of the operation data acquired by the data acquisition section160. Further, when there is an abnormality in the movement operation or the loading and unloading operations, the determination section170may generate a first movement signal to move the transport vehicle100to a self-testing area (not shown) connected to the transport rail10.

The determination section170may check whether the drive unit110, the slide unit130, the hoist unit140, and the hand unit150normally operate based of the operation data acquired by the data acquisition section160. For example, the determination section170may compare values measured by the sensors with predetermined reference values.

In particular, when difference values between the measured values and the reference values satisfy an allowable range, the determination section170may determine that the movement operation and the loading and unloading operations of the transport vehicle100are normal. Further, when the difference values between the measured values and the reference values are out of the allowable range, the determination section170may determine that an abnormality has occurred in the movement operation and/or the loading and unloading operations of the transport vehicle100.

When it is determined that there is an abnormality in the movement operation and the loading and unloading operations of the transport vehicle100, the determination section170may generate the first movement signal for moving the transport vehicle100to the self-testing area. As another example, when an abnormality occurs in the drive unit110, it may be impossible to move the transport vehicle100. In such case, the determination section170may notify the operator of the abnormality of the transport vehicle100by generating an alarm signal.

After the transport vehicle100moves to the self-testing area, the determination section170may self-test whether there is an abnormality in the transport vehicle100. For example, the determination section170may determine again whether the movement operation and the loading and unloading operations are abnormal based on the operation data acquired by the data acquisition section160.

When it is determined that there is no abnormality in the transport vehicle100as a result of the self-inspection, the determination section170may generate a return signal for moving the transport vehicle100to the transport rail10.

When an abnormality is detected in the transport vehicle100, the determination section170may check whether the abnormality can be self-corrected. When the abnormality cannot be self-corrected, the determination section170may generate a take-out signal to take out the transport vehicle100to the outside. Alternatively, when the abnormality can be self-corrected, the self-correction section180may self-correct the abnormality. In addition, after the self-correction is performed, the determination section170may generate a return signal for returning the transport vehicle100to the transport rail10.

The first communication section190may transmit the first movement signal, the alarm signal, the return signal, and the take-out signal to the control unit200. Also, the first communication section190may transmit the operation data acquired by the data acquisition section160to the abnormality prediction unit300.

The control unit200may include a second communication section210, a signal generation section220, and a path generation section230.

The second communication section210may be configured to enable wireless communication with the first communication section190, and may receive the first movement signal, the alarm signal, the return signal and the take-out signal from the first communication section190.

When the first movement signal is transmitted from the first communication section190to the second communication section210, the signal generation section220may generate a first control signal for moving the transport vehicle100to the self-testing area, and the second communication section210may transmit the first control signal to the transport vehicle100. Further, when the return signal is transmitted from the first communication section190to the second communication section210, the signal generation section220may generate a second control signal for returning the transport vehicle100onto the transport rail10, and the second communication section210may transmit the second control signal to the transport vehicle100.

Meanwhile, a take-out port (not shown) for taking out the transport vehicle100from the transport rail10to the outside may be connected to the transport rail10. When the take-out signal is transmitted from the first communication section190to the second communication section210, the signal generation section220may generate a third control signal for moving the transport vehicle100from the self-testing area to the take-out port, and the second communication section210may transmit the third control signal to the transport vehicle100.

When the alarm signal is transmitted from the first communication section190to the second communication section210, the signal generation section220may generate a second alarm signal to notify the operator of the abnormality of the transport vehicle100. For example, the signal generation section220may turn on a warning light or generate a buzzer sound.

When an abnormality occurs in the transport vehicle100as described above, the self-test and the self-correction of the transport vehicle100may be performed automatically. Further, when the self-correction of the abnormality is not possible, the transport vehicle100may be automatically taken out. Accordingly, the time and cost required for the management of the transport vehicle100may be significantly reduced, and the operation rate of the transport vehicle100may be greatly improved.

The path generation section230may generate a movement path of the transport vehicle100. For example, when the second communication section210receives the first movement signal from the first communication section190, the path generation section230may generate a first movement path from a current position of the transport vehicle100to the self-testing area. In this case, the current position information of the transport vehicle100may be received from the first communication section190together with the first movement signal, and the generated information on the first movement path may be transmitted to the transport vehicle100by the second communication section210.

When the second communication section210receives the return signal from the first communication section190, the path generation section230may generate a second movement path from the self-testing area to a predetermined position for the transport of the material, and the second communication section210may transmit information on the generated second movement path to the transport vehicle100.

Further, when the second communication section210receives the take-out signal from the first communication section190, the path generation section230may generate a third movement path from the self-testing area to the take-out port, and the second communication section210may transmit information on the generated third movement path to the transport vehicle100.

The abnormality prediction unit300may include a third communication section310, a prediction section320, and a storage section330.

The third communication section310may receive the operation data acquired by the data acquisition section160from the first communication section190, and the prediction section320may predict whether an abnormality will occur in the transport vehicle100using the received operation data.

The storage section330may store reference operation data of a plurality of reference transport vehicles, and the prediction section320may compare the received operation data with the reference operation data to predict an occurrence of an abnormality in the transport vehicle100.

For example, data on how the reference operation data of each of the reference transport vehicles changes for a predetermined time may be stored in the storage section330. The prediction section320may select reference operation data equal or similar to the received operation data by comparing the received operation data with the reference operation data.

Further, the prediction section320may check how the selected reference operation data changes during a predetermined time so as to predict the occurrence of abnormality in the transport vehicle100. For example, when a reference transport vehicle having the selected reference operation data operates normally for the predetermined time, the prediction section320may predict that the transport vehicle100will maintain a normal operating state for the predetermined time.

As another example, when an abnormality occurs within the predetermined time in the reference transport vehicle having the selected reference operation data, the prediction section320may predict that an abnormality will occur within the predetermined time in the transport vehicle100.

In particular, when it is predicted that an abnormality will occur in the transport vehicle100, the prediction section320may generate a second movement signal for moving the transport vehicle100to the self-testing area, and the third communication section310may transmit the second movement signal to the second communication section210. Further, the third communication section310may receive a current position information of the transport vehicle100from the first communication section190, and may transmit the current position information of the transport vehicle100to the second communication section210. In this case, the signal generation section220may generate a fourth control signal for moving the transport vehicle100to the self-testing area, and the second communication section210may transmit the fourth control signal to the transport vehicle100. Further, the path generation section230may generate a fourth movement path from the current position of the transport vehicle100to the self-testing area, and the second communication section210may transmit information on the generated fourth movement path to the transport vehicle100.

The transport vehicle100may move to the self-testing area using the fourth control signal and the fourth movement path, and then, the determination section170may self-test whether there is an abnormality in the transport vehicle100.

On the other hand, the third communication section310may periodically receive the operation data from the transport vehicle100, and the storage section330may store the received operation data. The operation data stored periodically as described above may be used as the reference operation data.

FIG.4is a flowchart illustrating a transport vehicle management method in accordance with an embodiment of the present invention.

Referring toFIG.4, in step S110, the transport vehicle100may be moved to the self-testing area connected to the transport rail10. Then, in step S120, the transport vehicle100may be self-tested to determine whether there is an abnormality in the transport vehicle100.

For example, while the transport vehicle100is operating, the data acquisition section160may generate a log file including operation data of the transport vehicle100by using values measured by the sensors mounted on the transport vehicle100. The determination section170may analyze the log file to determine whether there is an abnormality in the operations of the transport vehicle100. As an example, when a position control of the slide unit130is not precise, that is, when a difference value between position coordinates of the slide unit130moved for loading or unloading of the material and predetermined position coordinates is out of an allowable range, the determination section170may determine that an abnormality has occurred in the operations of the transport vehicle100, and may generate a first movement signal for moving the transport vehicle100to the self-testing area.

The first movement signal may be transmitted to the second communication section210of the control unit200by the first communication section190, and the signal generation section220of the control unit200may generate a first control signal for moving the transport vehicle100to the self-testing area. Further, the path generation section230may generate a first movement path from a current position of the transport vehicle100to the self-testing area, and the second communication section210may transmit the first control signal and information on the first movement path to the transport vehicle100.

As another example, when the prediction section320of the abnormality prediction unit300predicts that an abnormality will occur in the transport vehicle100, the transport vehicle100may move to the self-testing area. Alternatively, the transport vehicle100may periodically move to the self-testing area.

After the transport vehicle100moves to the self-testing area, the determination section170may self-test a home position and left and right limit adjustment state of the slide unit130, a deviation between a home position of the hoist unit140and a position of the hoist unit140, an operation time and sensor detection state of the hand unit150, a distortion and input/output of an obstacle sensor and a front distance sensor mounted on the frame unit120, and a sensing distance of the sensors for a movement of the drive unit110and loading and unloading of the material20, a recognition rate of barcode or QR code of a code reader mounted on the frame unit120, and a wear state of drive wheels111of the drive unit110.

In step S130, when an abnormality is detected in the transport vehicle100, the determination section170may determine whether the transport vehicle100is capable of self-correcting the detected abnormality. For example, when a position error occurs in an operation of the slide unit130, the determination section170may determine whether the position error of the slide unit130is self-correctable.

A dog bar131may be mounted on the slide unit130, and a home sensor133for detecting the dog bar131may be mounted on the frame unit120. For example, the dog bar131may be detected by the home sensor133while the slide unit130is moved in a horizontal direction. In particular, a distance that the slide unit130moves during a time that the dog bar131is detected by the home sensor133is a total length of the dog bar131, and the determination section170may determine whether the self-correction is possible by comparing the total length of the dog bar131with a predetermined reference length.

Specifically, when the total length of the dog bar131is different from the reference length, a failure may have occurred in the home sensor133, or damage may have occurred to the dog bar131. Accordingly, the determination section170may determine that the position error of the slide unit130cannot be self-corrected. In this case, the determination section170may generate a take-out signal for taking out the transport vehicle100to the outside, and the transport vehicle100may be taken out from the self-testing area in step S140. As another example, when the total length of the dog bar131is equal to the reference length, the determination section170may determine that the position error of the slide unit130is self-correctable.

Further, a left length that the dog bar131is detected may be measured while the slide unit130is moved from a predetermined home position in a right direction, and a right length that the dog bar131is detected may be measured while the slide unit130is moved from the predetermined home position in a left direction. The determination section170may compare the measured left length with the measured right length. As a result of the comparison, when the measured left length is equal to the measured right length, the determination section170may determine that the operating state of the slide unit130is normal. In such case, the determination section170may generate a return signal for returning the transport vehicle100onto the transport rail10, and the transport vehicle100may return to the transport rail10from the self-testing area for material transport in step S150.

On the other hand, when the measured left length and the measured right length are different from each other, the self-correction section180may correct the home position of the slide unit130so that the left length and the right length of the dog bar131are equal to each other in step S160.

After the self-correction is performed, the determination section170may generate a return signal for returning the transport vehicle100to the transport rail10, and the transport vehicle100may return to the transport rail10from the self-testing area for material transport in step S170.

FIG.5is a flowchart illustrating a transport vehicle management method in accordance with another embodiment of the present invention, andFIG.6is a flowchart illustrating a self-correcting step as shown inFIG.5.

Referring toFIGS.5and6, a transport vehicle management method, in accordance with another embodiment of the present invention, may be used to correct a position error of the slide unit130of the transport vehicle100when the position error occurs in the slide unit130. As shown inFIG.3, a dog bar131may be mounted on the slide unit130, and a home sensor133for detecting the dog bar131may be mounted on the frame unit120of the transport vehicle100.

In accordance with another embodiment of the present invention, in step S210, a total length of the dog bar131may be measured. For example, the total length of the dog bar131detected by the home sensor133may be measured while the slide unit130is moved in the horizontal direction. Specifically, the total length of the dog bar131may be a distance that the slide unit130moves while the dog bar131is detected by the home sensor133. As an example, the slide unit130may be moved in the horizontal direction by a driving section (not shown) such as a motor, and an encoder for measuring the number of revolutions of the motor may be mounted on the motor. The moving distance of the slide unit130may be calculated based on a signal of the encoder.

In step S220, the determination section170may determine whether the total length of the dog bar131is equal to a predetermined reference length. When the total length of the dog bar131is different from the reference length, it may be determined that a failure has occurred in the home sensor133or damage has occurred in the dog bar131. Accordingly, the determination section170may determine that the position error of the slide unit130cannot be self-corrected. In such case, the determination section170may generate a take-out signal for taking out the transport vehicle100to the outside, and the transport vehicle100may be taken out from the self-testing area in step S230.

When the total length of the dog bar131is equal to the reference length, a left length of the dog bar131may be measured in step S240, and a right length of the dog bar131may be measured in step S250. For example, after moving the slide unit130to a predetermined home position, the left length of the dog bar131may be acquired by measuring a moving distance of the slide unit130that the dog bar131is detected by the home sensor133while moving the slide unit130in a right direction. Further, after moving the slide unit130to the predetermined home position, the right length of the dog bar131may be acquired by measuring a moving distance of the slide unit130that the dog bar131is detected by the home sensor133while moving the slide unit130in a left direction.

In step S260, the determination section170may compare the measured left length and the measured right length of the dog bar131with each other. When the measured left length and the measured right length are equal to each other as a result of the comparison, the determination section170may determine that the operating state of the slide unit130is normal. In such case, the determination section170may generate a return signal for returning the transport vehicle100onto the transport rail10, and the transport vehicle100may return onto the transport rail10from the self-testing area for material transport in step S270.

When the measured left length and the measured right length are different from each other, the self-correction section180may correct the home position of the slide unit130so that the left length and the right length of the dog bar131are equal to each other in step S280. Specifically, as shown inFIG.6, in step S281, the determination section170may move the home position of the slide unit130by half of the difference between the two lengths in a longer direction among the measured left length and the measured right length. In step S282, the determination section170may set the moved home position as a new home position.

After correcting the home position of the slide unit130, the determination section170may generate a return signal for returning the transport vehicle100onto the transport rail10, and the transport vehicle100may return onto the transport rail10from the self-testing area for material transport in step S290.

In accordance with the embodiments of the present invention as described above, when an abnormality occurs in the transport vehicle100, the abnormality may be detected by self-test and may then be self-corrected. Accordingly, the time and cost required for managing the transport vehicle100may be significantly reduced.

Although the example embodiments of the present invention have been described with reference to the specific embodiments, they are not limited thereto. Therefore, it will be readily understood by those skilled in the art that various modifications and changes can be made thereto without departing from the spirit and scope of the appended claims.