Patent Document

BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a transfer apparatus for transferring a transported object, such as a container which accommodates or houses various substrates for manufacturing semiconductor devices, between a processing apparatus, such as a semiconductor manufacturing apparatus, and a transporting vehicle, such as a vehicle, which travels along a track. Here, the “transported object” in the present invention means a product, an intermediate product, a part, an article, a work, a partly-finished good, a good or the like (e.g. a semiconductor or LCD device), or means a box or container for containing such a product or the like (e.g, a container containing the semiconductor or LCD device), which has been transported or is to be transported by a transporting carriage. The load may be a carrier for containing an object to be carried such as a FOUP. 
         [0003]    2. Description of the Related Art 
         [0004]    As this kind of transfer apparatus, for example, such an apparatus is commercialized that is fixed to the outer frame of a processing apparatus or the exterior of an outer casing and that transfers a transported object, such as a container which is referred to as a FOUP (Front Opening Unified Pod), between the transfer apparatus and the processing apparatus or between the transfer apparatus and the transporting vehicle. Specifically, the transfer apparatus is equipped with two shelves, such as a port, for transferring the FOUP with the transporting vehicle on the top, and is equipped with six shelves, such as a buffer storage, for temporarily putting the FOUP below the port (e.g. refer to Japanese Patent No. 4182521). 
         [0005]    Moreover, as the aforementioned transfer apparatus, such an apparatus has been suggested that is provided with a plurality of shelves, each of which can support the transported object, such as a wafer support pod; and a gripper, which can be displaced to any position in an X-Z plane including the plurality of shelves. Specifically, this system supplies the wafer support pod to the processing apparatus, such as a semiconductor process tool and a measurement tool (e.g. refer to Japanese Patent Kohyo (Japanese translation of PCT international application) No. 2001-509465). 
         [0006]    However, the transfer apparatus described in Japanese Patent No. 4182521 and Japanese Patent Kohyo (Japanese translation of PCT international application) No. 2001-509465 is firmly fixed to the outer frame of the processing apparatus or the outer casing. In other words, once the transfer apparatus is fixed to the processing process, it takes a long time for an operation of canceling the fixation. Moreover, when the transfer apparatus is fixed to the processing apparatus, the transfer apparatus blocks the front of the processing apparatus (in particular, a wall portion in which the port for taking the transported object in and out exists). Thus, it is hard or impossible to perform operations associated with the repair, failure, and maintenance of the processing apparatus while the transfer apparatus remains fixed. In other words, in order to perform the operation associated with the repair or the like, there arises a time-consuming operation of detaching the transfer apparatus from the processing apparatus. Moreover, after that, when the transfer apparatus is fixed again to the processing apparatus, there also arises a new fixation operation between the two, which requires a certain degree of positioning accuracy. Moreover, with regard to the transfer apparatus, it is bulky in appearance to a non-negligible extent and its fixation position is limited, so that it will be a major hurdle when it is tried to save a space around the processing apparatus in a factory, which is technically problematic. 
       SUMMARY OF THE INVENTION 
       [0007]    It is therefore an object of the present invention to provide a transfer apparatus which can be easily fixed to a processing apparatus, with the entire apparatus miniaturized. 
         [0008]    The above object of the present invention can be achieved by a transfer apparatus for transferring a transported object with a transporting vehicle, which travels along a track and which transports the transported object, and with a port which can take in and out the transported object or a processed object in a processing apparatus which performs a process on the processed object accommodated in the transported object, the transfer apparatus provided with: a first shelf which is disposed to block an original transfer path in the middle which is from a transfer position at which the transporting vehicle transfers the transported object to the port and which can transfer the transported object with the transporting vehicle; a second shelf which can at least temporarily put the transported object; and a displacing device which can reciprocate the transported object with respect to the first shelf and the port in a first direction, which is a direction coming close to and going away from the processing apparatus, and which can reciprocate the transported object at a first direction position, which is away in the first direction at least by the transported object from the first shelf and the port, in a second direction crossing the first direction. 
         [0009]    The processing apparatus of the present invention is a semiconductor manufacturing apparatus, such as a process apparatus and an inspection apparatus, and it performs a predetermined process (e.g. an exposure process, film formation, heat treatment, or the like) on the transported object, such as a FOUP, and actually on the processed object, such as wafers accommodated in the transported object. When the process is performed, typically, the transported object to be processed is transported to the processing apparatus by the transporting vehicle, such as an OHT (Overhead Hoist Transport), which travels along the track laid on a ceiling in a factory, such as a semiconductor manufacturing factory, and it is transferred from the transporting vehicle or to the port which can transfer it to the transporting vehicle. After that, for example, the processed object accommodated in the transported object on the port is taken out of the transported object by the displacing device of the processing apparatus, and it is taken into and out of the processing apparatus. Incidentally, if the processing apparatus is provided with a buffer in a form of the processed object which is taken into or out of the processing apparatus as a processing target, it is not necessarily the processed object itself as described above, but it may be the transported object itself (i.e. the transported object which accommodates the processed object). 
         [0010]    Here, for example, in semiconductor manufacturing, it is a challenge to improve the operating rate of the processing apparatus in order to ensure more production without expanding manufacturing facilities. For example, it is assumed that a waiting time for the transported object (i.e. the down time of the processing apparatus) between when the transported object on which the process has been completed is taken away from the port by a first transporting vehicle and when the transported object to be processed from now is brought to the port by a second transporting vehicle is several minutes. In contrast, the operating rate of the processing apparatus is 50% if it takes several minutes for the process in a first transported object. As described above, in order to improve the operating rate which reduces in accordance with the waiting time, it is requested to reduce the down time of the processing apparatus by quickly removing the transported object on which the process has been completed in the processing apparatus from the port and by quickly putting the transported object to be processed next onto the port (i.e. by quickly replacing the transported object on the port). 
         [0011]    According to the transfer apparatus of the present invention, the transfer apparatus is a temporally-holding apparatus, such as a buffering apparatus for temporarily putting or holding the transported object on which the process is to be performed or has been performed by the processing apparatus. According to the transfer apparatus, for example, in the operation, firstly, the transportation and the process with respect to the first transported object are requested of three elements on the basis of a semiconductor manufacturing schedule by the controlling device in the manufacturing system for integrally controlling the transfer apparatus, the transporting vehicle, and the processing apparatus (hereinafter referred to as “three elements” as occasion demands). Then, the transporting vehicle which transports the first transported object is stopped at a position corresponding to the first shelf, and the first transported object is transferred from the transporting vehicle to the first shelf. Here, the “first shelf” means a shelf which is referred to as an “OHT port” and which has a put surface on which the transported object transferred from or to the transporting vehicle can be put. The first transported object transferred to the first shelf is transferred from the first shelf to the port by the displacing device, such as a robot arm which can hold the flange of a FOUP and a transfer mechanism which can support the transported object from below. After that, the processed object accommodated in the first transported object is displaced from the inside of the transported object on the port to the inside of the processing apparatus, for example, by an inner and outer displacing device in the processing apparatus. Then, the process is performed on the processed object within the processing apparatus. Then, the transportation and the process with respect to a second transported object to be processed next are requested of the three elements. Then, the transporting vehicle which transports the second transported object is stopped at the position corresponding to the first shelf, and the second transported object is transferred (i.e. brought) from the transporting vehicle to the first shelf. Then, the second transported object on the first shelf is transferred from the first shelf to the second shelf by the displacing device. Here, the “second shelf” means a shelf which is referred to as a “buffer” or a “buffer shelf” and which has a put surface on which either the first or second transported object can be temporarily put in order to replace the transported object on the port from the first transported object on which the process has been completed to the second transported object on the first shelf to be processed next. Then, if the process has been completed on the first processed object (actually, the processed object in the first transported object), the processed object is displaced by the inner and outer displacing device from the inside of the processing apparatus to the inside of the first transported object on the port. Then, the transportation (i.e. taking away) of the first transported object on which the process has been completed is requested of the transporting vehicle which is closest to the transfer apparatus or the processing apparatus, out of unloaded transporting vehicles which do not transport the transported object. After that, in parallel with that the first transported object on the port is transferred by the displacing device from the port to the first shelf (i.e. that the first transported object on which the process has been completed is taken away from the port), the transportation and the process (i.e. bringing in) with respect to a third transported object to be processed next to the second transported object are requested of the three elements. Then, the second transported object on the second shelf is transferred from the second shelf to the port, and the replacement of the transported object on the port is quickly performed. After that, by the transporting vehicle which is requested to transport the first transported object on which the process has been completed, the first transported object on the first shelf is transferred from the first shelf to the transporting vehicle (i.e. taken away). On the other hand, if the process has been completed on the second transported object on the port (actually, the processed object in the second transported object), the transportation (i.e. taking away) of the second transported object on which the process has been completed is requested of the transporting vehicle which is unloaded and which is closest to the transfer apparatus or the processing apparatus. As described above, by transferring the transported object to be processed from now to the first shelf in order and by using the second shelf to efficiently replace the transported object on the port on which the process has been completed by the transported object on the first shelf, it is possible to improve the operating rate of the processing apparatus. 
         [0012]    As described above, the transfer apparatus of the present invention is provided only with: the one second shelf for replacing the transported object in the one port; and the first shelf for transferring the transported object with the transporting vehicle, as the shelf which can put or transfer the transported object. Thus, it is possible to make the transfer apparatus small and light. Moreover, in the situation that the transfer apparatus is miniaturized, the transfer apparatus can be easily fixed to the one port (or processing apparatus), and there is provided the displacing apparatus which can be displaced among the one port, the first shelf, and the second shelf. Thus, the connection may be unnecessary. 
         [0013]    Moreover, according to the transfer apparatus of the present invention, with regard to the inner arrangement and the outer arrangement, firstly, the first shelf is disposed to block the original transfer path in the middle which is from the transfer position at which the transporting vehicle transfers the transported object, typically, the transfer position at which the transporting vehicle performs longitudinal transfer in the vertical direction, to the port. Thus, as viewed from the transporting vehicle side, it is possible to perform the transfer operation on the port if there is no transfer apparatus and to perform the transfer operation on the first shelf if there is the transfer apparatus, in almost the same manner. Moreover, the displacing device can reciprocate the transported object with respect to the first shelf and the port in the first direction (e.g. horizontal one direction), which is a direction coming close to and going away from the processing apparatus, and more specifically, an outer frame, outer casing surface, side surface, or side wall on which the port is provided in the processing apparatus. Moreover, the displacing device can reciprocate the transported object at the first direction position (e.g. horizontal direction position), which is away in the first direction at least by the transported object from the first shelf and the port, in the second direction (e.g. vertical direction). Thus, it is possible to include a path or space for displacing the transported object in the transfer apparatus, in an extremely small space. In particular, if such a condition is added that the second shelf which functions as the buffer does not block the path or space in the direction reciprocation of the transported object between the first shelf and the port, it is possible to approximately minimize the path or space for displacing the transported object in the transfer apparatus as described above. In other words, it is possible to reduce the width of the path or space for displacing the transported object in the transfer apparatus, within the width of the port. Thus, with respect to one processing apparatus provided with a plurality of ports, it is also possible to dispose the same number of transfer apparatuses as the number of ports in line along the track. In other words, it is also possible to make the outer width of the outer frame or outer casing or the like of the transfer apparatus, equal to, or less than or equal to the pitch of the ports. By this, it is also possible to select whether or not to use the transfer apparatus for each port, as occasion demands. 
         [0014]    In one aspect of the transfer apparatus of the present invention, the second shelf is disposed at a position of the first direction position, which is not obstructive when the displacing device displaces the transported object in the first direction and the second direction between the first shelf and the port. 
         [0015]    According to this aspect, the second shelf is disposed at the position of the first direction position (e.g. a position at which a distance in the horizontal direction from the outer wall on which the port is provided in the processing apparatus is fixed), which is not obstructive when the transported object is displaced in the first direction (e.g. horizontal direction) and the second direction (e.g. vertical direction) between the first shelf and the port. Specifically, for example, the second shelf is disposed near the lower limit in the movable range in the vertical direction of the displacing device, at the horizontal direction position located slightly below the port, which is close to the port disposed below the first shelf. Alternatively, the second shelf is disposed near the upper limit in the movable range in the vertical direction of the displacing device, at the horizontal direction position located slightly above the first shelf. Thus, it is possible to approximately minimize the path or space for displacing the transported object in the transfer apparatus while the second shelf which particularly functions as the buffer does not block the path or space in the direct displacement of the transported object between the first shelf and the port. Thus, it is possible to approximately minimize the outer shape of the outer frame or outer casing or the like of the transfer apparatus. 
         [0016]    Alternatively, in another aspect of the transfer apparatus of the present invention, the second shelf is disposed between the first shelf and the port in the original transfer path. 
         [0017]    According to this aspect, the second shelf is disposed between the first shelf and the port in the original transfer path, and the three parts of the first shelf, the second shelf, and the port are disposed in such a form that they are distant from each other. Therefore, it is possible to approximately minimize the path or space for displacing the transported object in the transfer apparatus while not blocking the path or space in the displacement of the transported object among the three parts at a second direction position. Thus, it is possible to approximately minimize the outer shape, such as the outer frame and outer casing, of the transfer apparatus. 
         [0018]    In another aspect of the transfer apparatus of the present invention, the processing apparatus has a plurality of ports, and the transfer apparatus has a width which is less than or equal to an arrangement pitch of the ports in its outside dimension and is disposed such that the first direction matches a direction which is at right angles to a direction of arranging the ports. 
         [0019]    According to this aspect, the transfer apparatus has the width which is less than or equal to the arrangement pitch of the ports in its outside dimension, and typically, the first direction matches the direction which is at right angles to the direction of arranging the ports, wherein the direction of arranging the ports is along the track. Thus, it is possible to place a plurality of transfer apparatuses correspondingly to the ports, in a one-to-one manner. Since the width of the transfer apparatus is small with respect to the width direction of the port, it is also possible to arrange the plurality of transfer apparatuses in accordance with the arrangement of the ports. 
         [0020]    In another aspect of the transfer apparatus of the present invention, the first shelf can be bent or accommodated on a main body side of the transfer apparatus. 
         [0021]    According to this aspect, if the transfer apparatus is removed for maintenance or the like or is installed, the first shelf is bent or accommodated on the main body side of the transfer apparatus. By this, it is only necessary to pull out or displace the transfer apparatus which is narrowed by the bent or accommodated portion, so that it is extremely useful in practice. 
         [0022]    Incidentally, if the second shelf is disposed between the first shelf and the port in the original transfer path, it may be also constructed such that the second shelf can be bent or accommodated on a main body side of the transfer apparatus. 
         [0023]    Specifically, the first shelf and/or the second shelf are fixed to one portion of a slide mechanism, and they are slide below the track or to the horizontal one direction position. For example, the first shelf and/or the second shelf are rotatably fixed to a hinge, and they are displaced to a put position horizontally disposed below the track, or an accommodation position vertically disposed in an accommodation device. 
         [0024]    In another aspect of the transfer apparatus of the present invention, the transporting vehicle longitudinally transfers the transported object in a vertical direction, the first direction is a horizontal one direction which is perpendicular to the vertical direction, and the second direction is the vertical direction. 
         [0025]    According to this aspect, the transporting vehicle can perform the longitudinal transfer on the port along the original transfer path which extends in the vertical direction if the transfer apparatus is not provided in the processing apparatus, and the transporting vehicle can also perform the longitudinal transfer on the first shelf along the original transfer path in the same manner even if the transfer apparatus is provided in the processing apparatus. Moreover, by the displacing device displacing the transported object put on the first shelf in the horizontal one direction and the vertical direction, it is possible to displace it to the second shelf or the port. Alternatively, by the displacing device displacing the transported object put on the port in the horizontal one direction and the vertical direction, it is possible to displace it to the second shelf or the first shelf. 
         [0026]    In this aspect, the transporting vehicle is provided with, for example, a hoist mechanism which can hoist the transported object, and the hoist mechanism holds the transported object within the transporting vehicle in the transportation (i.e. including the travel in the transportation) and brings down or pulls up the transported object in the vertical direction with a transfer shelf, such as a stocker or the port, of the processing apparatus or the like, in the transfer. Here, the “longitudinal transfer” in the transporting vehicle means that the transported object is transferred by the displacement in the vertical direction. Typically, the port of the processing apparatus is placed in the vertical direction of the track. In this case, according to this aspect, the first shelf is disposed between the port and the transporting vehicle which is stopped at the transfer position, and the second shelf is disposed below the first shelf, specifically, between the first shelf and the port, or below the port. 
         [0027]    In another aspect of the transfer apparatus of the present invention, the transfer apparatus has an outer shape which allows the transfer apparatus to be attached to the port, and the transfer apparatus is further provided with a positioning device for positioning the transfer apparatus with respect to the port. 
         [0028]    According to this aspect, the main body of the transfer apparatus is, for example, an outer frame, outer casing, case, or frame. According to this aspect, the transfer apparatus is attached to the port such that there is the port in an area in the first direction (e.g. horizontal one direction) and the second direction (e.g. vertical direction) to which the displacing device can reach, in the operation. For the attachment, for example, the transfer apparatus main body has the outer shape which avoids the port and the transported object on the port. Moreover, the transfer apparatus has the outer shape which opens a portion adjacent to the transported object on the port in the transfer apparatus main body such that the displacing device can transfer the transported object with the port. 
         [0029]    Moreover, according to this aspect, for example, it is possible to position the transfer apparatus by setting one portion of the transfer apparatus to the positioning device, such as a positioning block or pin, placed below the port or on the floor surface below the transfer apparatus. Incidentally, the positioning device may be provided not only on the floor surface but also on an inner wall or the like in a factory, such as a semiconductor manufacturing factory, rail, processing apparatus, or port. 
         [0030]    In this aspect, the transfer apparatus may be further provided with a fixing device which fixes the transfer apparatus in a state that the transfer apparatus is positioned by the positioning and which can release the fixation. 
         [0031]    By virtue of such construction, it is possible to fix the transfer apparatus by fixing one portion of the positioned transfer apparatus to the fixing device which is fixed on the floor surface, rail, or ceiling and which is made of a high-strength material. 
         [0032]    In another aspect of the transfer apparatus of the present invention, it is further provided with a travelling device which enables the transfer apparatus to be displaced in the first direction. 
         [0033]    According to this aspect, the transfer apparatus can be displaced by providing a plurality of travelling devices, such as a travel roller and a travel caterpillar, on the bottom surface of the transfer apparatus main body. In particular, in the attachment to the port, the transfer apparatus is displaced in the first direction, which is horizontal one direction, with respect to the port. In other words, the transfer apparatus can be arbitrarily attached or detached with respect to the port. Incidentally, the travelling device may be a transportation carriage which can support the transfer apparatus from below even if it is not provided for the transfer apparatus main body. 
         [0034]    In another aspect of the transfer apparatus of the present invention, the displacing device has: a holding device for holding the transported object; a first displacing part capable of reciprocating the holding device in the first direction; and a second displacing part capable of reciprocating the holding device in the second direction. 
         [0035]    According to this aspect, the displacing device holds the transported object by using the holding device, such as a gripper which can hold the upper part of the transported object and a transfer mechanism which can support the transported object from below, in the operation. Then, the displacing device which holds the transported object is displaced in the first direction (e.g. horizontal one direction) and the second direction (e.g. vertical direction) among the port, the first shelf, and the second shelf (i.e. the three element) by the first displacing device, which is, for example, a horizontal displacing device, driven by the power of an actuator, a motor, or the like, and the second displacing device, which is, for example, a vertical displacing device. As described above, it is possible to quickly displace the transported object onto an arbitrary put surface of the three elements, by simple biaxial operation performed by the two-direction displacing devices. 
         [0036]    In another aspect of the transfer apparatus of the present invention, it is further provided with a controlling device for controlling the displacing device, if one transported object transferred from the transporting vehicle to the first shelf is displaced to the port, firstly to displace the one transported object from the first shelf to the second shelf, secondly to displace another transported object, which is put on the port, from the port to the first shelf while the one transported object is temporarily put on the second shelf, and thirdly to displace the one transported object from the second shelf to the port. 
         [0037]    According to this aspect, if the one transported object is transferred from the transporting vehicle to the first shelf, the one transported object is firstly displaced to the second shelf by the displacing device, under the control of the controlling device including a controller or the like. Then, while the one transported object is temporarily put on the second shelf, the other transported object, on which the process has been completed by the processing apparatus and which is put on the port, is displaced to the first shelf by the displacing device. After that, the one transported object temporarily put on the second shelf is displaced to the port by the displacing device, and it is used for the subsequent process by the processing device. 
         [0038]    As described above, it is possible to prioritize carrying out the other transported object on which the process has been completed to the first shelf, over carrying the one transported object into the port. By this, for example, it is possible to appropriately respond to the situation that the entire operation efficiency can be increased by rapidly transporting the transported object on which the process has been completed by using the transporting vehicle. 
         [0039]    In another aspect of the transfer apparatus of the present invention, it is further provided with a controlling device for controlling the displacing device, if one transported object transferred from the transporting vehicle to the first shelf is displaced to the port, firstly to displace the one transported object to the port without temporarily putting the one transported object on the second shelf on which another transported object transferred to the second shelf is already put, and secondly to displace the other transported object from the second shelf to the first shelf. 
         [0040]    According to this aspect, if the one transported object is transferred from the transporting vehicle to the first shelf, the one transported object is displaced directly to the port without being displaced to the second shelf, by the displacing device, under the control of the controlling device including a controller or the like. On the other hand, when the one transported object is displaced from the first shelf to the port, the other transported object is already put on the second shelf. Normally, the predetermined process is already performed on the other transported object by the processing apparatus. After that, the other transported object is displaced from the second shelf to the first shelf and is transported from the first shelf by the transporting vehicle which is closest and empty or the transporting vehicle which arrives next. 
         [0041]    As described above, it is possible to carry out the other transported object on which the process has been completed to the first shelf after carrying the one transported object into the port. By this, for example, for example, it is possible to appropriately respond to the situation that the entire operation efficiency can be increased by rapidly transporting the unprocessed transported object to the processing apparatus. 
         [0042]    Incidentally, the aforementioned two types of control in the two aspects can be also selectively performed according to circumstances. For example, any of the two types of control may be selected and performed, as occasion demands, in accordance with various situations, such as a processing standby situation and a transfer standby situation of the transported object on the port, a transfer standby situation and a transportation standby situation in the first shelf. 
         [0043]    The above object of the present invention can be also achieved by a second transfer apparatus for transferring a transported object with a transporting vehicle, which travels along a track and which transports the transported object, and with a port which can take in and out the transported object or a processed object in a processing apparatus which performs a process on the processed object accommodated in the transported object, the transfer apparatus provided with: a first shelf which is disposed to block an original transfer path in the middle which is from a transfer position at which the transporting vehicle transfers the transported object to the port and which can transfer the transported object with the transporting vehicle; a second shelf which can at least temporarily put the transported object; and a displacing device which can reciprocate the transported object with respect to the first shelf and the port in a third direction, which is a direction along the processing apparatus and which is a direction coming close to and going away from the port, and which can reciprocate the transported object at a third direction position, which is away in the third direction at least by the transported object from the first shelf and the port, in a second direction crossing the third direction. 
         [0044]    According to the second transfer apparatus of the present invention, firstly, the first shelf is disposed or constructed to be disposed to block the original transfer path in the middle which is from the transfer position at which the transporting vehicle transfers the transported object (typically, the transfer position at which the transporting vehicle performs longitudinal transfer in the vertical direction) to the port, as in the first shelf of the transfer apparatus of the present invention described above (hereinafter referred to as a “first transfer apparatus” as occasion demands). On the other hand, the displacing device can reciprocate the transported object with respect to the first shelf and the port in the third direction (e.g. horizontal one direction), which is the direction along the processing apparatus, which is, more specifically, a direction along the outer frame surface, outer casing surface, side surface, or side wall on which the port is disposed in the processing apparatus, and which is the direction coming close to and going away from the port. Correspondingly to this, the displacing device can reciprocate the transported object at the third direction position (e.g. horizontal direction position), which is away in the third direction from the first shelf and the port, in the second direction (e.g. vertical direction). Thus, with regard to the inner arrangement of the transfer apparatus, as in the first transfer apparatus, it is possible to include a path or space for displacing the transported object in the transfer apparatus in the third direction and the second direction, in an extremely small space. 
         [0045]    Therefore, according to the second transfer apparatus of the present invention, if there is an obstacle in the first direction (i.e. in front) of the port when the transported object is transferred between the transporting vehicle and the first shelf, it is possible to disposed the first shelf in the original transfer path by bringing the first shelf close to the port in the third direction. In other words, the transfer apparatus can be disposed on the side of or right beside the port, or right beside the processing apparatus, in accordance with the placed position of the port in the processing apparatus. Thus, with regard to the outer arrangement of the transfer apparatus, the transfer apparatus does not occupy a space in front of the port of the processing apparatus in the transfer or the transported object and does not block a passage of an operator and equipment or the like in the space. In other words, it is possible to narrow the space in accordance with the arrangement of the transfer apparatus. 
         [0046]    On the other hand, according to the second transfer apparatus of the present invention, it is possible to certainly reduce the protrusion of the transfer apparatus into the path for the passage of the operator and equipment or the like (i.e. including the aforementioned space), in comparison with the first transfer apparatus which brings the first shelf close to the port in the first direction. 
         [0047]    In one aspect of the second transfer apparatus of the present invention, the transfer apparatus is disposed such that the third direction matches a direction along the track. 
         [0048]    According to this aspect, when the transported object is transferred between the transporting vehicle and the first shelf, for example, if there is an obstacle in the first direction of the processing apparatus (specifically, in front of the port of the processing apparatus), it is possible to bring the transfer apparatus close to the port in the third direction, with the first shelf in front, in order to dispose the first shelf in the original transfer path. In other words, the transfer apparatus can be certainly disposed right beside the port, regardless of the placed position of the port in the processing apparatus. Thus, with regard to the outer arrangement of the transfer apparatus, the transfer apparatus does not occupy a space at all in front of the port of the processing apparatus and does not block the passage of the operator and equipment or the like in the space, by being displaced in the third direction which matches the direction along the track in the transfer of the transported object. In other words, it is possible to narrow the space in accordance with the arrangement of the transfer apparatus. 
         [0049]    Incidentally, even the second transfer apparatus of the present invention can also adopt the same various aspects as those of the first transfer apparatus described above. 
         [0050]    The nature, utility, and further features of this invention will be more clearly apparent from the following detailed description with reference to preferred embodiments of the invention when read in conjunction with the accompanying drawings briefly described below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0051]      FIG. 1  is a perspective view showing the overall structure of a manufacturing system provided with a transfer apparatus in a first embodiment; 
           [0052]      FIG. 2  is a cross sectional view in one direction showing the transfer apparatus in  FIG. 1 ; 
           [0053]      FIG. 3  is a cross sectional view in another direction showing the transfer apparatus in  FIG. 1 ; 
           [0054]      FIG. 4  is a flowchart showing a first transfer operation process in the first embodiment; 
           [0055]      FIG. 5  is a flowchart showing a second transfer operation process in the first embodiment; 
           [0056]      FIG. 6  is a cross sectional view in one direction showing the transfer apparatus of the present invention, which is different from the transfer apparatus in  FIG. 1 ; 
           [0057]      FIG. 7  is a top view showing the panoramic view of a transportation system in  FIG. 1 ; 
           [0058]      FIG. 8  is a cross sectional view in one direction showing the transfer apparatus of the present invention which is different from the transfer apparatuses in  FIG. 1  and  FIG. 6 ; 
           [0059]      FIG. 9  are a top view and a side view showing a positioning device in the first embodiment; 
           [0060]      FIG. 10  are a top view and a side view showing one example of the positioning device of the present invention which is different from the positioning device in  FIG. 9 ; 
           [0061]      FIG. 11  are a top view and a side view showing one example of the positioning device of the present invention which is different from the positioning devices in  FIG. 9  and  FIG. 10 ; 
           [0062]      FIG. 12  are a top view and a side view showing one example of the positioning device of the present invention which is different from the positioning devices in  FIG. 9  to  FIG. 11 ; 
           [0063]      FIG. 13  is a side view showing one example of the fixing device of the present invention; 
           [0064]      FIG. 14  is a side view showing one example of the fixing device of the present invention; 
           [0065]      FIG. 15  are a top view and a side view showing one example of the travelling device of the present invention; 
           [0066]      FIG. 16  is a one-direction cross sectional view showing one example of the fixing device of the present invention; 
           [0067]      FIG. 17  is a one-direction cross sectional view showing one example of the fixing device of the present invention; 
           [0068]      FIG. 18  are a top view and a side view showing one example of the fixing device of the present invention; 
           [0069]      FIG. 19  are a top view and a side view showing one example of the fixing device of the present invention; 
           [0070]      FIG. 20  is a perspective view showing the overall structure of a manufacturing system provided with a transfer apparatus in a second embodiment; 
           [0071]      FIG. 21  is a cross sectional view in another direction showing the transfer apparatus in  FIG. 20 ; 
           [0072]      FIG. 22  is a top view showing the transfer apparatus in  FIG. 20 ; 
           [0073]      FIG. 23  is a top view showing one example of the second transfer apparatus of the present invention which is different from the transfer apparatus in  FIG. 20 ; and 
           [0074]      FIG. 24  is a cross sectional view in another direction showing one example of the second transfer apparatus of the present invention which is different from the transfer apparatuses in  FIG. 20  and  FIG. 23 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0075]    Hereinafter, embodiments of the present invention will be explained with reference to the drawings. 
       First Embodiment 
     Structure of Manufacturing System 
       [0076]    Firstly, the structure of a manufacturing system provided with a transfer apparatus in a first embodiment will be explained with reference to  FIG. 1  to  FIG. 3 .  FIG. 1  is a perspective view schematically showing the overall structure of the manufacturing system provided with the transfer apparatus in the first embodiment.  FIG. 2  is a one-direction cross sectional view conceptually showing a cross section if the transfer apparatus in  FIG. 1  is cut in one direction (i.e. an anteroposterior or front-back direction in  FIG. 1 ).  FIG. 3  is an another-direction cross sectional view conceptually showing a cross section if the transfer apparatus in  FIG. 1  is cut in another direction (i.e. in a horizontal direction in  FIG. 1 ). 
         [0077]    In  FIG. 1 , a manufacturing system  100  is provided with a rail  1 , a vehicle  10 , a manufacturing apparatus  20 , and a buffer apparatus  30 . The manufacturing system  100  has a transportation function, which allows the vehicle  10  to travel along the rail  1  and which transports a FOUP 3  (i.e. one example of the “transported object” of the present invention) which can accommodate or house a plurality of wafers (i.e. one example of the “processed object” of the present invention) to the manufacturing apparatus  20 ; and a manufacturing function, which performs various processes on the wafers in the FOUP 3  by using the manufacturing apparatus  20 , thereby manufacturing a semiconductor element. 
         [0078]    The rail  1  serves as a track for the vehicle  10  traveling, as one example of the “track” of the present invention. The rail  1  is laid on a ceiling in a factory in which the manufacturing system  100  is placed. 
         [0079]    The vehicle  10  is an OHT (Overhead Hoist Transport) driven by using a linear motor as power, as one example of the “transporting vehicle” of the present invention, and it is attached to the rail  1  in a suspended form. The vehicle  10  travels along the rail  1  and transports the FOUP 3  not only to the manufacturing apparatus  20  but also to a stocker, OHT buffer, large-scaled stocker, or the like not illustrated. The operations, such as transportation and travel, of the vehicle  10  are controlled by a not-illustrated controller in the manufacturing system  100 . Incidentally, for convenience of explanation, only one vehicle  10  is illustrated on the rail  1 ; however, typically, more vehicles  10  (e.g. several tens or several hundreds) are provided. 
         [0080]    The vehicle  10  is provided therein with a hoist mechanism  11 , which has a winding device  12  having a not-illustrated winding shaft, a winding belt  13 , and a gripper  14 . One end of the winding belt  13  is fixed to the winding shaft, and the other end is fixed to the gripper  14 . The winding device  12  rotates the winding shaft by using a not-illustrated motor as power, and it can wind up or wind off the winding belt  13  from the one end. The gripper  14  can be displaced into a holding state in which an upper part (i.e. flange)  3   a  of the FOUP 3  is held on the both ends of the gripper  14  which are bent inward, or into a release state in which the flange  3   a  of the FOUP 3  is released. By the winding belt  13  being wound up or wound off, the hoist mechanism  11  having such a structure hoists the gripper  14  in a vertical direction below the rail  1  and displaces the gripper  14  at a vertical position, thereby transferring the FOUP 3  from the vehicle  10  side to the buffer apparatus  30  side described later, or from the buffer apparatus  30  side to the vehicle  10  side. As described above, in the embodiment, a transfer path by the vehicle  10  extends downward in the vertical direction from the transfer position of the vehicle  10  (i.e. a stop position shown in  FIG. 1 ) to longitudinally transfer the FOUP 3 . 
         [0081]    The manufacturing apparatus  20  performs a predetermined process on the FOUP 3 , and actually on the wafers accommodated in the FOUP 3 , as one example of the “processing apparatus” of the present invention. The manufacturing apparatus  20  is provided therein with a not-illustrated processing device for performing the predetermined process on the wafers, and two openings H 1  and H 2  which can bring in and out the wafer to be processed, in the processing device. The manufacturing apparatus  20  is provided with two load ports LP 1  and LP 2  which function as ports for transferring the FOUP 3  with the buffer apparatus  30 , in the exterior adjacent to each of the two openings H 1  and H 2  and below the rail  1 . The manufacturing apparatus  20  is provided with a not-illustrated inner and outer transfer mechanism which brings in and out the wafers, which are in the FOUP 3  transferred to each of the two load ports LP and LP 2 , in the processing device through the opening H 1  or H 2 . The operations, such as bringing in and out the wafers, and the predetermined process, of the manufacturing apparatus  20  are controlled by the controller in the manufacturing system  100 . Incidentally, for convenience of explanation, only one manufacturing apparatus  20  is illustrated below the rail  1 ; however, typically, more manufacturing apparatuses  20  (e.g. several or several hundreds) are provided which perform different processes on the FOUP 3 . Moreover, the number of the openings and the load ports are not limited to two but may be three or more, and the arrangement thereof can be also in various aspects. 
         [0082]    The buffer apparatus  30  transfers the FOUP 3  with the vehicle  10  and with the manufacturing apparatus  20  such that the FOUP 3  is efficiently transferred between the vehicle  10  and the manufacturing apparatus  20 , as one example of the “transfer apparatus” of the present invention. Incidentally, for convenience of explanation, only one buffer apparatus  30  corresponding to the one load port LP 1  is illustrated on the manufacturing apparatus  20  provided with the two load ports LP 1  and LP 2 ; however, two buffer apparatuses  30  each corresponding to respective one of the load ports LP 1  and LP 2  may be provided as another embodiment. 
         [0083]    The buffer apparatus  30  is provided with a main body part  31 , an OHT port P 1 , a buffer P 2 , and a transfer mechanism  32 . In  FIG. 2 , the main body part  31  is an inverted L-shaped case which can be installed or attached from the front side (i.e. the left side in  FIG. 2 ) to the load port LP 1 . The main body part  31  is disposed such that a longitudinal direction is a direction perpendicular to the orientation of the rail  1  (i.e. one example of the “horizontal one direction” of the present invention and an X direction in  FIG. 2 ) in the installation or attachment. The main body part  31  has a length (i.e. a length Lx in  FIG. 2 ) which allows at least two FOUPs  3  to be disposed in the X direction and has a length (i.e. a length Lw in  FIG. 3 ) which allows at least one FOUP 3  to be disposed in the orientation of the rail  1 . Incidentally, for convenience of explanation, the structure of the buffer apparatus  30  in which the main body part  31  is attached to the load port LP 1  will be explained. 
         [0084]    Within the main body part  31 , there are placed the OHT port P 1 , the buffer P 2 , and the transfer mechanism  32 . The main body part  31  is provided with an opening H 11  which can transfer the FOUP 3  between the OHT port P 1  and the vehicle  10 , on an upper surface corresponding to the vertical direction of the rail  1  (i.e. shown by an alternate long and short dash line G 1  in  FIG. 2  and  FIG. 3 ). Moreover, the main body part  31  is provided with an opening H 12  which can transfer the FOUP 3  with the load port LP 1  (i.e. the manufacturing apparatus  20 ), on the side surface adjacent to the FOUP 3  put on the load port LP 1 . 
         [0085]    The OHT port P 1  functions as a port of the buffer apparatus  30  for transferring the FOUP 3  on which the predetermined process is to be performed or has been performed in the manufacturing apparatus  20 , through the opening H 11  with the vehicle  10 , as one example of the “first shelf” of the present invention. The OHT port P 1  is placed above the load port LP 1  in the vertical direction of the rail  1  such that the vehicle  10  can transfer the FOUP 3  in a short time by longitudinal transfer (i.e. transfer which allows the FOUP 3  to be displaced only in the vertical direction in the transfer). As is clear from  FIG. 1  to  FIG. 3 , the OHT port P 1  exists at a position to block the transfer path (i.e. the “original transfer path” of the present invention) when the vehicle  10  longitudinally transfers the FOUP 3  with respect to the load port LP 1  of the manufacturing apparatus  20  if the buffer apparatus  30  is removed. Thus, as viewed from the vehicle  10 , it is only necessary to perform the transfer operation on the port which is at the same position in planar view, i.e. which is below the transfer position in the vertical direction, regardless of the presence of the buffer apparatus  30 . In other words, if there is only a difference in the height of the port as viewed from the vehicle  10 , the control with respect to the transfer operation by the vehicle  10  is almost the same, regardless of the presence of the buffer apparatus  30 , so that it is extremely useful in practice. 
         [0086]    The buffer P 2  functions as a temporary put shelf for at least temporarily putting the FOUP 3  on which the predetermined process is to be performed or has been performed in the manufacturing apparatus  20 , as one example of the “second shelf” of the present invention. The buffer P 2  is placed below the load port LP 1  in the vertical direction of the rail  1  and in the X direction so that it does not block the transfer of the FOUP 3  by the transfer mechanism  32  described later. 
         [0087]    The transfer mechanism  32  is displaced among the load port LP 1 , the OHT port P 1 , and the buffer P 2  and transfers the FOUP 3  among them, as one example of the “displacing device” of the present invention. The transfer mechanism  32  is provided with a holding device  33 , a horizontal displacement mechanism  34 , and a hoist mechanism  35 , and it is placed on the front side of the main body part  31  (i.e. the left side in  FIG. 2 ). The holding device  33  is one example of the “holding device” of the present invention and has a pair of planar portions. The planar portions enter below the flange  3   a  in the X direction and support the both ends of the flange  3   a  from the below, thereby holding the FOUP 3 . As shown in  FIG. 2 , the horizontal displacement mechanism  34  is one example of the “horizontal displacing device” of the present invention, and it is provided with a rail part  34   a  placed such that the longitudinal direction is parallel to the X direction; and a slide part  34   b  which can be slid in the X direction along the rail part. To the tip of the horizontal transfer mechanism  34  (i.e. the end on the manufacturing apparatus  20  side of the slide part  34   b ), the holding device  33  is fixed. The hoist mechanism  35  is one example of the “vertical displacing device” of the present invention, and it is provided with a turn belt  35   a  which can turn in the vertical direction by using a not-illustrated motor as a power source; and a hoist device  35   b  which is displaced in the vertical direction with the turn of the turn belt. To the hoist device  35   b , one end of the rail part  34   a  is fixed. 
         [0088]    The transfer mechanism  32  displaces the holding device  33  in the X direction (i.e. one example of the “first direction” of the present invention) and in the vertical direction (e.g. one example of the “second direction” of the present invention) among the load port LP 1 , the OHT port P 1 , and the buffer P 2  by the mutual operation performed by the horizontal transfer mechanism  34  and the hoist mechanism  35  described above, and the transfer mechanism  32  holds or releases the FOUP 3  on the holding device  33 , thereby transferring the FOUP 3  among them. The operations, such as the displacement of the transfer mechanism  32  and the transfer of the FOUP 3 , are controller by the controller in the manufacturing system  100 . 
         [0089]    &lt;First Transfer Operation Process in Manufacturing System&gt; 
         [0090]    Next, the transfer operation between the transporting vehicle and the processing apparatus via the transfer apparatus in the manufacturing system  100  will be explained with reference to  FIG. 4 .  FIG. 4  is a flowchart showing the first transfer operation process in the first embodiment. 
         [0091]    In  FIG. 4 , firstly, an instruction to transport the FOUP  3  to the manufacturing apparatus  20  is given to the vehicle  10  which holds the FOUP  3  on which the process in the manufacturing apparatus  20  is to be performed, by the controller in the manufacturing system  100 . Here, it is assumed that the FOUP which is the first transportation target is “FOUP 0 ”. After that, on the basis of the instruction from the controller, the vehicle  10  (i.e. written as “OHT” in  FIG. 4 ) travels along the rail  1  and stops at a predetermined transfer position corresponding to the buffer apparatus  30  (i.e. stop position shown in  FIG. 1  to  FIG. 3 ). Then, by the hoist mechanism  11 , the gripper  14  holding the FOUP 0  is lowered in the vertical direction through the opening H 11  in the buffer apparatus  30  from the inside of the vehicle  10 , and the FOUP 0  is released from the gripper  14  at the vertical position at which the FOUP 0  is in contact with the upper surface of the OHT port P 1 . In other words, the FOUP 0  is transferred from the vehicle  10  to the OHT port P 1  (step S 51 ). 
         [0092]    Then, in the buffer apparatus  30 , the holding device  33  is displaced to below the flange  3   a  of the FOUP 0  on the OHT port P 1  by the horizontal displacement mechanism  34 , and the hoist mechanism  35  before the holding device  33  is raised until it comes into contact with the lower surface of the flange  3   a . In this manner, the FOUP 0  is held by the holding device  33 . Then, the holding device  33  which holds the FOUP 0  is displaced to above the load port LP 1  (i.e. written as “L port” in  FIG. 6 ) through the opening H 12  before the holding device  33  is lowered until the FOUP 0  comes into contact with the load port LP 1 . In this manner, the FOUP 0  is transferred from the OHT port P 1  to the load port LP 1  (step S 52 ). After that, the holding device  33  is horizontally displaced to the side of the FOUP 0  on the load port P 1 , and the FOUP 0  is released from the holding device  33 . The wafers in the FOUP 0  transferred to the load port LP 1  are temporarily accommodated in the manufacturing apparatus  20 , and the predetermined process is performed inside before the wafers are put into the FOUP 0  on the load port LP 1  again. 
         [0093]    Then, on the basis of a new instruction from the controller, as in the operation in the step S 51 , a FOUPn (i.e. “n” is a variable indicating the order that the FOUP 3  is transported) which is a second transportation target is transferred onto the OHT port P 1  from the vehicle  10  which has arrived at a new transfer position which is different from the previous one (step S 53 ). Then, the holding device  33  which holds the FOUPn on the OHT port P 1  is displaced to above the buffer P 2  by the horizontal displacement mechanism  34  and the hoist mechanism  35  before the holding device  33  is lowered until the FOUPn comes into contact with the buffer P 2 . In this manner, the FOUPn is transferred from the OHT port P 1  to the buffer P 2  (step S 54 ). 
         [0094]    Then, it is judged whether or not the predetermined process in the manufacturing apparatus  20  has been completed on the FOUP (here, FOUP 0 ) on the load port LP 1 , by the controller (step S 55 ). As a result of the judgment, if it is judged that the predetermined process has not been completed (the step S 55 : NO), it becomes in a standby state until the predetermined process has been completed. 
         [0095]    On the other hand, as a result of the judgment in the step S 55 , if it is judged that the predetermined process has been completed on the FOUP (here, FOUP 0 ) on the load port LP 1  (the step S 55 : YES), the FOUP on which the process has been completed is transferred from the load port LP 1  to the OHT port P 1  by the transfer mechanism  32  (step S 56 ). At this time, the FOUP on which the process has been completed is displaced to the OHT port P 1  such that it slips through above the FOUPn put on the buffer P 2 . Then, the FOUPn is transferred from the buffer P 2  to the load port LP 1  by the transfer mechanism  32  which is unloaded (i.e. which no longer holds the FOUP 3 ) (step S 57 ). 
         [0096]    After that, on the basis of the instruction from the controller, the vehicle  10  of the transfer mechanism  32  which is unloaded (i.e. which no longer holds the FOUP 3 ) is stopped at a predetermined transfer position. Then, the unloaded gripper  14  is lowered in the vertical direction through the opening H 11  by the hoist mechanism  11 , and the FOUP on which the process has been completed is held by the gripper  14 . In other words, the FOUP on which the process has been completed is transferred from the OHT port P 1  to the vehicle  10  (step S 58 ). After that, the gripper  14  which holds the FOUP on which the process has been completed is raised by the hoist mechanism  11  and is held within the vehicle  10 . In this manner, the vehicle  10  becomes in the state that it can travel. 
         [0097]    Then, it is judged whether or not there is an instruction to transport the FOUP 3  to be processed, by the controller (step S 59 ). As a result, if it is judged that there is the instruction (the step S 59 : YES), the FOUP which is a third transportation target is set to “FOUPn+1” (step S 60 ). Then, as in the operation in the step S 51 , the FOUPn+1 which is the third transportation target is transferred to the OHT port P 1  from the vehicle  10  which has arrived at a new transfer position which is different from the previous one, as the operation in the step S 53  again. After that, the FOUPn+1 is transferred from the OHT port P 1  to the buffer P 2 , as the operations in the step S 54  to the step S 59 . Then, it is judged whether or not the predetermined process has been completed on the FOUP (here, FOUPn) on the load port LP 1 , and when it is judged that the predetermined process has been completed, the FOUP on which the process has been completed is transferred from the load port LP 1  to the OHT port P 1 . Then, after the FOUPn+1 is transferred from the buffer P 2  to the load port LP 1 , if the FOUP on which the process has been completed is transferred from the OHT port P 1  to the vehicle  10 , it is judged whether or not there is another instruction to transport the FOUP 3  to be processed. 
         [0098]    On the other hand, as a result of the judgment in the step S 59 , if it is judged that there is no further instruction (the step S 59 : NO), it is judged whether or not the predetermined process has been completed on the FOUP (here, FOUPn+x (i.e. “n+x” is shown by the FOUP 3  which is the last transportation target)) on the load port LP 1  as the operations in the steps S 55 , S 56 , and S 58 . If the predetermined process has been completed, when the last FOUP on which process has been completed is transferred from the load port LP 1  to the OHT port P 1 , the last FOUP is transferred from the OHT port P 1  to the vehicle  10 . By this, all the FOUPs 3  on which the predetermined process is performed in the manufacturing apparatus  20  are transferred to the vehicle  10  through the buffer apparatus  30 , and the series of first transfer operation process is ended. 
         [0099]    As described above, according to the first transfer operation process in the embodiment, it is possible to improve the operating rate of the manufacturing apparatus  20  by using the buffer P 2  for replacing the FOUP 3  on the load port LP 1  to efficiently replace the FOUP 3  on which the process has been completed by the FOUP 3  to be processed from now. 
         [0100]    Incidentally, the operation in the step S 58  may be performed in tandem with the step S 57  if it is after the FOUP 3  on which the process has been completed is transferred to the OHT port P 1  as the operation in the step S 56 . 
         [0101]    &lt;Second Transfer Operation Process in Manufacturing System&gt; 
         [0102]    Next, another transfer operation which is different from the first transfer operation in  FIG. 4  will be explained with reference to  FIG. 5 .  FIG. 5  is a flowchart showing a second transfer operation process in the first embodiment. 
         [0103]    In  FIG. 5 , firstly, as in the case of  FIG. 4 , an instruction to transport the FOUP 3  to the manufacturing apparatus  20  is given to the vehicle  10  which holds the FOUP  3  on which the process in the manufacturing apparatus  20  is to be performed, by the controller in the manufacturing system  100 . Here, it is assumed that the FOUP which is the first transportation target is “FOUP 0 ”. After that, on the basis of the instruction from the controller, the FOUP 0  is transferred from the vehicle  10  (i.e. written as “OHT” in  FIG. 5  as in the case of  FIG. 4 ) to the OHT port P 1  (step S 61 ). Then, in the buffering apparatus  30 , the FOUP 0  is transferred from the OHT port P 1  to the load port LP 1  (i.e. written as “L port” in  FIG. 5  as in the case of  FIG. 4 ) by the transfer mechanism (step S 62 ). Then, it is judged whether or not the predetermined process in the manufacturing apparatus  20  has been completed on the FOUP (here, FOUP 0 ) on the load port LP 1  (step S 63 ). As a result of the judgment, if it is judged that the predetermined process has not been completed (the step S 63 : NO), it is continued until the predetermined process has been completed. 
         [0104]    On the other hand, as a result of the judgment in the step S 63 , if it is judged that the predetermined process has been completed on the FOUP (here, FOUP 0 ) on the load port LP 1  (the step S 63 : YES), it is judged whether or not there is an instruction to transport the FOUP 3  to be processed, by the controller (step S 64 ). As a result, if it is judged that there is the instruction (the step S 64 : YES), the FOUP on which the process has been completed is transferred from the load port LP 1  to the buffer P 2  by the transfer mechanism  32  (step S 65 ). Then, if the FOUPn which is the second transportation target is transferred from the vehicle  10  to the OHT port P 1  on the basis of a new instruction from the controller (step S 66 ), the FOUPn is directly transferred from the OHT port P 1  to the load port LP 1  (step S 67 ). In other words, as opposed to the case of the first transfer operation process described above, the FOUPn before the processing is not temporarily put on the buffer P 2 . Then, the FOUP on which the process has been completed (here, FOUP 0 ) is transferred from the buffer P 2  to the OHT port P 1  (step S 68 ). After that, the FOUP is transferred from the OHT port P 1  to the vehicle  10  (step S 69 ). Here, the FOUP which can be the third transportation target is set to “FOUPn+1” (step S 70 ). 
         [0105]    Then, as in the operation in the step S 63  and the step S 64  again, it is judged whether or not the predetermined process in the manufacturing apparatus  20  has been completed on the FOUP on the load port LP 1 , and when it is judged that the predetermined process has been completed, it is judged whether or not there is an instruction to transport the FOUP 3  to be processed next. 
         [0106]    On the other hand, as a result of the judgment in the step S 64 , if it is judged that there is no further instruction (the step S 64 : NO), the FOUP on which the process has been completed is transferred from the load port LP 1  to the OHT port P 1  (step S 71 ), and then, the FOUP is transferred from the OHT port P 1  to the vehicle  10  (step S 72 ). By this, as in the first transfer operation in  FIG. 4 , all the FOUPs 3  on which the predetermined process is performed in the manufacturing apparatus  20  are transferred to the vehicle  10  through the buffer apparatus  30 , and the series of second transfer operation process is ended. 
         [0107]    As described above, according to the second transfer operation process in the embodiment, if the predetermined process has been completed in the manufacturing apparatus  20 , the FOUP 3  on the load port LP 1  is removed immediately after that, and the FOUP to be processed next is put onto the load port LP 1  (actually, the wafers in the FOUP 3  are brought into the manufacturing apparatus  20 ). Therefore, it is possible to further improve the operating rate of the manufacturing apparatus  20 . 
         [0108]    Incidentally, according to the first embodiment, the OHT port P 1  is disposed above the load port LP 1  in the vertical direction of the rail  1 , and the buffer P 2  is disposed below the load port LP 1  in the vertical direction and in the X direction; however, the arrangement of the buffer is not limited to this.  FIG. 6  is a one-direction cross sectional view for explaining one example of the arrangement which is different from the arrangement of the second shelf in the embodiment. In  FIG. 6 , in a buffering apparatus  130 , a buffer P 12  is disposed between an OHT port P 11  and a load port LP 11  in a vertical direction G 1  of the rail  1 . A transfer mechanism  132  is displaced among the buffer P 12 , the OHT port P 11 , and the load port LP 11 , and the FOUP 3  can be transferred among them. By this, even in the arrangement of the buffer P 12 , it is possible to obtain the same operation and effects as those in the buffer apparatus  30  in the first embodiment described above. 
         [0109]    Incidentally, according to the first embodiment, the buffer apparatus  30  has the length Lx which allows at least two FOUPs  3  to be disposed in the X direction (i.e. the longitudinal direction of the buffer apparatus  30 , which is one example of the “first direction” of the present invention) which crosses the orientation of the rail  1  at right angles in the state that it is attached to the load port LP 1 ; however, the form of the buffer apparatus  30  is not limited to this.  FIG. 7  is a top view schematically showing the panoramic view of a transportation system provided with the transfer apparatus in the embodiment. In  FIG. 7 , a transportation system  300  is provided with a plurality of manufacturing apparatuses  20  and  220 . The plurality of manufacturing apparatuses  20  and  220  are provided with a path (i.e. a hatching portion in  FIG. 7 ) which is used for a system administrator or the like who administrates the transportation system in the failure or maintenance of any element, to carry in and out broken equipment or maintenance equipment, or to place the transfer apparatus of the present invention. The plurality of manufacturing apparatuses  20  and  220  are placed in two lines such that the path is between them and such that the load ports LP 1 , LP 2 , and LP 21  to LP 23  are disposed on the path side. As shown in  FIG. 7 , the width of the path Lth (i.e. the shortest distance between the load ports LPs in a pair of manufacturing apparatuses opposed to each other across the path) is less than a length La in the X direction of the buffer apparatus  30  in the first embodiment. Thus, the buffer apparatus  30  cannot be attached to any of the load ports. 
         [0110]      FIG. 8  is a one-direction cross sectional view for explaining one example of the outer shape which is different from the outer shape of the transfer apparatus in the first embodiment. In  FIG. 8 , a buffer apparatus  230  which is also shown in  FIG. 7  has a length Ly obtained by combining a length of a space required for a transfer mechanism  232  to be displaced in the vertical direction and a length which allows one FOUP 3  to be disposed, in the X direction, before and after it is attached to the load port LP 1  (i.e. except the attachment). The length Ly is less than the width of the path Lth. This is because a storage mechanism  40  which can be stored in a main body part  231  is provided before and after an OHT port P 21  is attached to the load port LP 1 . The storage mechanism  40  is provided with a storage device  41  and a hinge device  42 . The accommodation device  41  is placed in the vicinity of an opening  211  which can let the FOUP 3  through by the transfer of the transfer mechanism  232  in the main body part  231 , and the accommodation device  41  accommodates or houses the OHR port P 21  in the perpendicular direction. The hinge  42  rotatably connects one end of the OHT port P 21  with the accommodation device  41 , and the hinge  42  can displace the OHT port P 21  between a transfer position opposed to the rail  1  and an accommodation position at which it is accommodated in the accommodation device  41 . 
         [0111]    As shown in  FIG. 8 , when the buffer apparatus  230  is attached to the load port LP 1 , the buffer apparatus  230  is displaced on the path in  FIG. 7  in the state that the OHT port P 21  is accommodated at the accommodation position (i.e. the state of a buffer mechanism  230 A in  FIG. 8 ), and it is disposed on the front side (i.e. the left side in  FIG. 8 ) of the load port LP 1  which is an attachment target. Then, the buffer apparatus  230  is attached to the load port LP 1  in the state that the OHT port P 21  is displaced to the transfer position (i.e. the state of a buffer mechanism  230 B in  FIG. 8 ). In the attachment, the OHT port P 21  is disposed in the vertical direction of the rail  1 . As described above, by providing the accommodation mechanism  40  which can accommodate the OHT port P 21 , it is possible to make the buffer apparatus compact and light. Therefore, it facilitates the displacement of the buffer apparatus, and it increases the degree of freedom in the attachment of the buffer apparatus. 
         [0112]    &lt;Method of Positioning Transfer Apparatus&gt; 
         [0113]    Next, a method of positioning the transfer apparatus of the present invention will be explained with reference to  FIG. 9  to  FIG. 15 . Each of  FIG. 9  is a top view or a side view showing one example of a positioning device for positioning the buffer apparatus with respect to the manufacturing apparatus  20  in  FIG. 1  to  FIG. 3 . 
         [0114]      FIG. 9A  is a top view showing the buffer apparatus  30  in the first embodiment poisoned (in other words, attached) with respect to the manufacturing apparatus  20  in the first embodiment, and  FIG. 9B  is a side view showing the buffer apparatus  30  in  FIG. 9A . In  FIG. 9A , the buffer apparatus  30  is provided with a cylindrical abutting part  4  on the side surface on the load port LP 1  side. In contrast, on a floor surface between the buffer apparatus  30  and the manufacturing apparatus  20  (i.e. below the load port LP 1  in  FIG. 1  to  FIG. 3 ), there is placed a poisoning block  5  (i.e. one example of the “positioning device” of the present invention) in which one surface is formed in a tapered shape. The buffer apparatus  30  is set into a displacement state described later when it is attached to the load port LP 1 , and the buffer apparatus  30  is displaced in the X direction until the abutting part  4  abuts on the positioning block  5 . By this, the buffer apparatus  30  is positioned with respect to the manufacturing apparatus  20 . 
         [0115]    In  FIG. 9B , the buffer apparatus  30  is provided with a plurality of travel roller  38  for displacement and a plurality of legs  39  each of which makes a pair with respective one of the plurality of travel rollers  38 , on the bottom surface. Each travel roller  38  is provided with a caster  38   a  and a jack bolt  38   b  which can extend and contract the caster  38   a  in the perpendicular direction. Each leg  39  is provided with a support part  39   a  which is in contact with the floor surface and which supports the main body of the buffer apparatus  30 ; and an adjuster  39   b  which fixes the support part  39   a  to the floor surface of the buffer apparatus  30  without displacing the support part  39   a . When the buffer apparatus  30  is displaced, the jack bolts  38   a  are tightened counterclockwise. Then, the buffer apparatus  30  becomes in the state that the casters  38   a  extending from the main body of the buffer apparatus  30  come into contact with the floor surface and that the support parts  39   a  are released from the floor surface (i.e. the displacement state of the buffer apparatus). In this state, the buffer apparatus  30  can be easily displaced by rotating the caster  38   a . Moreover, by the abutting part  4  abutting on the positioning block  5 , the jack bolts  38   b  are tightened clockwise when the buffer apparatus  30  positioned with respect to the manufacturing apparatus  20  is fixed. Then, the buffer apparatus becomes in the state that the casters  38   a  contracted toward the main body of the buffer apparatus  30  are released from the floor surface and that the support parts  39   a  are in contact with the floor surface (i.e. the fixed state of the buffer apparatus). In this state, the buffer apparatus  30  is stably disposed. 
         [0116]      FIG. 10(   a ) is a top view showing the buffer apparatus  130  positioned with respect to the load port LP 1 , and  FIG. 10(   b ) is a side view showing the buffer apparatus  130  in  FIG. 10(   a ). Incidentally, in  FIG. 10 , the same constituent elements as in the case of the buffer apparatus  30  in  FIG. 9  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0117]    In  FIG. 10(   a ), the buffer apparatus  130  is provided with an abutting part  104  in which an abut surface is formed in a tapered shape, on the side surface on the load port LP 1  side. In contrary, on a floor surface between the buffer apparatus  130  and the manufacturing apparatus  20  (i.e. below the load port LP 1  in  FIG. 1  to  FIG. 3) , there is placed a cylindrical poisoning pin  105  (i.e. one example of the “positioning device” of the present invention). The buffer apparatus  130  is set into the displacement state when it is attached to the load port LP 1 , and the buffer apparatus  130  is displaced in the X direction until the abutting part  104  abuts on the positioning pin  105 . By this, the buffer apparatus  130  is positioned with respect to the manufacturing apparatus  20 . 
         [0118]      FIG. 11(   a ) is a top view showing the buffer apparatus  230  positioned with respect to the load port LP 1 , and  FIG. 11(   b ) is a side view showing the buffer apparatus  230  in  FIG. 11(   a ). Incidentally, in  FIG. 11 , the same constituent elements as in the case of the buffer apparatus  30  in  FIG. 9  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0119]    In  FIG. 11(   a ), the buffer apparatus  230  is provided with an abutting part  204  in which an abut surface is formed in a tapered shape, on the side surface on the load port LP 1  side. In contrary, on a floor surface between the buffer apparatus  230  and the manufacturing apparatus  20  (i.e. below the load port LP 1  in  FIG. 1  to  FIG. 3) , there are placed two cylindrical poisoning pins  205   a  and  205   b  (i.e. one example of the “positioning device” of the present invention). The buffer apparatus  230  is set into the displacement state when it is attached to the load port LP 1 , and the buffer apparatus  230  is displaced in the X direction until the two positioning pins  205   a  and  205   b  engage with the abutting part  204 . By this, the buffer apparatus  230  is positioned with respect to the manufacturing apparatus  20 , more accurately than in the case of one positioning pin. 
         [0120]      FIG. 12(   a ) is a top view showing a buffer apparatus  330  positioned with respect to the load port LP 1 , and  FIG. 12(   b ) is a side view showing the buffer apparatus  330  in  FIG. 12(   a ). Incidentally, in  FIG. 12 , the same constituent elements as in the case of the buffer apparatus  130  in  FIG. 10  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0121]    In  FIG. 12(   a ), the buffer apparatus  330  is provided with not only the abutting part  104  which abuts on the positioning pin  105  (i.e. one example of the “positioning device” of the present invention) but also an engagement part  36  (i.e. one example of the “positioning device” and the “fixing device” of the present invention) which can certainly lock the main body of the buffer apparatus  330  on the positioning pin  105 . One end of the engagement part  36  is rotatably mounted on the side surface on the load port LP 1  side, and the other end is bent so that it engages with the positioning pin  105  at a predetermined turn position. The buffer apparatus  330  is provided with a lock lever  38  on the side surface on the opposite side of the load port LP 1 . The lock lever  37  can be operated by the system administrator, and it can displace the engagement part  36  between a lock position which is the aforementioned predetermined turn position and at which the main body of the buffer apparatus  330  is locked with respect to the positioning pin  105  (i.e. shown by the engagement part  36  in a dashed line in  FIG. 12A)  and a non-lock position which is a turn position initially set and at which the main body of the buffer apparatus  330  is released (i.e. shown by the engagement part  36  in a solid line in  FIG. 12A ). In the attachment to the load port LP 1 , firstly, the buffer apparatus  330  is set into the displacement state, and the lock lever  37  is displaced to the non-lock position. Then, the buffer apparatus  330  is displaced in the X direction until the abutting part  104  abuts on the positioning pin  105 , and then, the engagement part  36  is displaced to the lock position. After that, the buffer apparatus  330  is set into the fixed state and is fixed at the position that the buffer apparatus is positioned. By this, the buffer apparatus  330  is positioned with respect to the manufacturing apparatus  20 , more accurately and certainly than the case where it is positioned only by the abutting part  104 . 
         [0122]    &lt;Method of Fixing Transfer Apparatus&gt; 
         [0123]      FIG. 13  is a side view showing a buffer apparatus  430  positioned with respect to the load port LP 1 . Incidentally, in  FIG. 13 , the same constituent elements as in the case of the buffer apparatus  330  in  FIG. 12  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0124]    In  FIG. 13 , on a floor surface on which a buffer apparatus  430  positioned with respect to the manufacturing apparatus  20  is disposed, there are placed convex cones  406  (i.e. one example of the “fixing device” of the present invention). In contrast, a plurality of legs  439  of the buffer apparatus  430  have support parts  439   a  which are formed in a concave shape and which engage with the cones  406  on their contact surfaces with floor surface. When the buffer apparatus  430  is displaced, the jack bolts  38   b  are tightened counterclockwise, and the extended casters  38   a  come into contact with the floor surface. At the same time, the support parts  439   a  are set into the aforementioned displacement state that they are released from the floor surface (i.e. the floor surface including the portions in which the cones  406  are placed). When the buffer apparatus  430  positioned with respect to the manufacturing apparatus  20  is fixed, the jack bolts  38   b  are tightened clockwise, and the contracted casters  38   a  are released from the floor surface. At the same time, the support parts  439   a  are set into the aforementioned fixed state that they engage with the cones  406 . By this, the buffer apparatus  430  is disposed more stably than the case of a simple flat floor surface. 
         [0125]      FIG. 14  is a side view showing the buffer apparatus  430  positioned with respect to the load port LP 1 , as in  FIG. 13 . Incidentally, in  FIG. 14 , the same constituent elements as in the case of the buffer apparatus  430  in  FIG. 13  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0126]    In  FIG. 14 , on a floor surface on which the buffer apparatus  430  positioned with respect to the manufacturing apparatus  20  is disposed, there are placed the same cones  407  (i.e. one example of the “fixing device” of the present invention) as the cones  406  in  FIG. 13 . However, portions  6  of the floor surface in which the cones  407  are placed are lower than the original floor surface on which the manufacturing apparatus  20 , the buffer apparatus  430 , and the like are placed, by the height of the cones  407 . This is to avoid a danger to a person, such as the system administrator tripping over or falling on the cones which project from the floor surface. As in the case of  FIG. 13 , when the buffer apparatus  430  is displaced, the jack bolts  38   b  are tightened counterclockwise, and the extended casters  38   a  come into contact with the original floor surface. At the same time, the support parts  439   a  are set into the aforementioned displacement state that they are released from the floor surface (i.e. the floor surface including the portions  6  in which the cones  407  are placed). When the buffer apparatus  430  positioned with respect to the manufacturing apparatus  20  is fixed, the jack bolts  38   b  are tightened clockwise, and the contracted casters  38   a  are released from the original floor surface. At the same time, the support parts  439   a  are set into the aforementioned fixed state that they engage with the cones  407 . By this, the buffer apparatus  430  is disposed more stably than the case of the simple flat floor surface, as in the case of  FIG. 13 , while avoiding the danger to a person caused by the placement of the cones  407 . 
         [0127]    &lt;Method of Travelling Transfer Apparatus&gt; 
         [0128]      FIG. 15A  is a top view showing a buffer apparatus  530  positioned with respect to the load port LP 1 , and  FIG. 15B  is a side view showing the buffer apparatus  530  in  FIG. 15A . Incidentally, in  FIG. 15 , the same constituent elements as in the case of the buffer apparatus  30  in  FIG. 9  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0129]    In  FIG. 15 , the buffer apparatus  530  is not provided with a travelling device, such as the travel roller  38  in  FIG. 9 , and the buffer apparatus  530  cannot be displaced by itself. Thus, for the displacement of the buffer apparatus  530 , a jack carriage  50  (i.e. one example of the “travelling device” of the present invention) is used. The jack carriage  50  is provided with a not-illustrated hydraulic jack part; a support table  51 , which can support the bottom surface of the main body of the buffer apparatus  530 ; a plurality of roller parts  52 , which have wheels and which are displaceably mounted on the bottom surface of the support table  51 ; a handhold  53 , which is held by the system administrator when the jack carriage  50  is displaced (i.e. including when the buffer apparatus  530  is displaced). When the buffer apparatus  530  supported by the plurality of legs  39  is displaced after being positioned with respect to the manufacturing apparatus  20 , firstly, the roller parts  52  are inclined (i.e. shown by the roller parts in dashed lines in  FIG. 15B ) by the power of the jack part, thereby setting the support table  51  at a level (i.e. entrance level) which allows the support table  51  to enter below the main body of the buffer apparatus  530 . Then, the jack carriage  50  is displaced in the X direction by the operation of handhold  53 , and the support table  51  at the entrance level is disposed below the center of the main body of the buffer apparatus  530  away from the plurality of legs  39 . Then, by the operation of the jack part, the inclined roller parts  52  are made vertical (i.e. shown by the roller parts in solid lines in  FIG. 15B ). Then, the plurality of legs  39  are released from the floor surface, and the support table  51  is set at a level (i.e. support level) which allows the support table  51  to be in contact with the bottom surface of the main body of the buffer apparatus  530 , so that the buffer apparatus  530  is set into the displacement state. After that, if the jack carriage  50  is pulled in the X direction from a position at which an abutting part  33  abuts on the positioning block  5  and is released from a position at which the buffer apparatus  530  is positioned with respect to the manufacturing apparatus  20  by the operation of the handhold  53 , the buffer apparatus  530  can be arbitrarily displaced. The displacement here may be performed by man power, or by using an external or built-in power mechanism, such as an electric motor. Incidentally, if the buffer apparatus  530  in displacement is positioned with respect to the manufacturing apparatus  20 , the aforementioned processes may be performed in the reverse order. 
         [0130]    &lt;Method of Fixing Upper Part of Transfer Apparatus&gt; 
         [0131]    Next, with reference to  FIG. 16  and  FIG. 17 , a method of fixing the transfer apparatus in the first embodiment will be explained.  FIG. 16  is a one-direction cross sectional view showing one example of the fixing device for fixing the transfer apparatus in the embodiment.  FIG. 17  is a one-direction cross sectional view for explaining one example of the fixing device in another form which is different from the fixing device in  FIG. 16 . Incidentally, in  FIG. 16  and  FIG. 17 , the same constituent elements as in the case of the buffer apparatus  230  in  FIG. 8  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0132]    In  FIG. 16 , the buffer apparatus  330  is provided with a fixation part  63  for fixing the upper part of the main body of the buffer apparatus  530 . The fixation part  63  has an opening which can let through a connection bolt  62  described later. In contrast, a bracket  60  (i.e. one example of the “fixing device” of the present invention) which can be connected to the fixation part  63  is fixed to a rail  301 . The bracket  60  is provided with a main body part  61  and the connection bolt  62 . One end of the main body part  61  is fixed on the side surface of the rail  301 , and the other end has an opening which can screw in the connection bolt  62 . If the buffer apparatus  330  is positioned with respect to the manufacturing apparatus  20 , the other end abuts on the fixation part  63  on the buffer apparatus  330  side. In this condition, the fixation part  63  is screwed to the main body part  61  by using the connection bolt  62 , by which the upper part of the buffer apparatus  330  is fixed and the buffer apparatus  30  is more stably disposed. 
         [0133]    In  FIG. 17 , a bracket  70  (one example of the “fixing device” of the present invention) is fixed on the ceiling, with respect to the fixation part  63  of the buffer apparatus  330  which is also shown in  FIG. 16 . The bracket  70  is provided with a main body part  71  and a connection bolt  72 , as in the bracket  60  in  FIG. 16 . When the buffer apparatus  330  is positioned with respect to the manufacturing apparatus  20 , the fixation part  63  is screwed to the main body part  71  by using the connection bolt  72  while the other end of the main body part  71  abuts on the fixation part  63  on the buffer apparatus  330  side, by which the upper part of the buffer apparatus  330  is fixed and the buffer apparatus  30  is more stably disposed. 
         [0134]    &lt;Method of Fixing Lower Part of Transfer Apparatus&gt; 
         [0135]      FIG. 18A  is a top view showing a buffer apparatus  630  positioned with respect to the load port LP 1 , and  FIG. 18B  is a side view showing the buffer apparatus  630  in  FIG. 18A . Incidentally, in  FIG. 18 , the same constituent elements as in the case of the buffer apparatus  30  in  FIG. 9  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0136]    In  FIG. 18 , a fixation pin  7  (one example of the “fixing device” of the present invention) for fixing the lower part of the main body of the buffer apparatus  630  is fixed on the bottom surface of the buffer apparatus  630 . The fixation pin  7  is provided with a main body part  7   a , a horizontal positioning part  7   b , and a fixation bolt  7   c . The main body part  7   a  has a concave portion on the side surface, and it can extend and contract in the perpendicular direction. One end of the horizontal positioning part  7   b  can engage with the concave portion of the main body part  7   a  in the horizontal one direction, and the other end has an opening which can let through the fixation bolt  7   c . In contrast, a fixation part  8  is placed on the floor surface corresponding to the aforementioned fixation pin  7  of the buffer apparatus  630  positioned with respect to the manufacturing apparatus  20 . The fixation part  8  has a concave portion which can engage with the fixation pin  7  and an opening which can screw in the fixation bolt  7   c , on the upper surface. When the buffer apparatus  630  positioned with respect to the manufacturing apparatus  20  is fixed, the main body part  7   a  abuts on the concave portion of the fixation part  8 , and one end of the horizontal positioning part  7   b  engages with the concave portion of the main body part  7   a  in the horizontal one direction. In this condition, the horizontal positioning part  7   b  is screwed to the fixation part  8  by using the fixation bolt  7   c , by which the lower part of the buffer apparatus  630  is fixed on a predetermined horizontal surface and the buffer apparatus  30  is disposed more stably than the case where the legs  39  are simply in contact with the floor surface. 
         [0137]      FIG. 19A  is a top view showing a buffer apparatus  730  positioned with respect to the load port LP 1 , and  FIG. 19B  is a side view showing the buffer apparatus  730  in  FIG. 19A . Incidentally, in  FIG. 19 , the same constituent elements as in the case of the buffer apparatus  30  in  FIG. 9  described above will carry the same referential numerals, and the explanation thereof will be omitted. 
         [0138]    In  FIG. 19 , a fixation pin  107  (one example of the “fixing device” of the present invention) for fixing the lower part of the main body of the buffer apparatus  730  is fixed on the bottom surface of the buffer apparatus  730 . The main body of the fixation pin  107  can extend and contract in the perpendicular direction, partially as in the fixation pin  7  in  FIG. 18 . A portion  108  on the floor surface corresponding to the fixation pin  107  of the buffer apparatus  730  positioned with respect to the manufacturing apparatus  20  is lower than the original floor surface on which the manufacturing apparatus  20 , the buffer apparatus  730 , and the like are placed so that it can engage with the fixation pin  107 . When the buffer apparatus  730  positioned with respect to the manufacturing apparatus  20  is fixed, the fixation pin  107  is extended and engages with the portion  108  of the floor surface. By this, the lower part of the buffer apparatus  730  is fixed in the horizontal direction and the buffer apparatus  30  is disposed more stably than the case where the legs  39  are simply in contact with the floor surface. 
         [0139]    Incidentally, the positioning device, the fixing device, and the travelling device shown in  FIG. 9  to  FIG. 19  described above may be provided alone for the transfer apparatus of the present invention. Alternatively, one or a plurality of combinations of the plurality of devices may be provided. 
         [0140]    The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be regarded in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing or following description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. For example, a transfer apparatus provided with two second shelves for two ports (i.e. in which two transfer apparatuses in the embodiment are arranged side by side) is also included in the technical scope of the invention. 
       Second Embodiment 
       [0141]    Next, the structure of a manufacturing system provided with a transfer apparatus in a second embodiment will be explained with reference to  FIG. 20  to  FIG. 22 .  FIG. 20  is a perspective view schematically showing the appearance of a manufacturing system provided with the transfer apparatus in  FIG. 8 , as a second embodiment.  FIG. 21  is an another-direction cross sectional view conceptually showing a cross section when the transfer apparatus shown in  FIG. 20  is cut in another direction (i.e. vertical direction in  FIG. 20 ).  FIG. 22  is a top view showing the arrangement of the transfer apparatus shown in  FIG. 20  with respect to a processing apparatus. Incidentally, in  FIG. 20  and  FIG. 22 , the same constituent elements as in the case of the manufacturing system  300  in  FIG. 8  described above will carry the same referential numerals, and the explanation thereof will be omitted. The specification which is different from the case of the manufacturing system  300  in  FIG. 8  will be particularly explained. 
         [0142]    In  FIG. 20 , a manufacturing system  1100  is different from the manufacturing system  300  in  FIG. 8  in that the buffer apparatus  230  is disposed on the side surface side (the right side in  FIG. 20 ) of the load port LP 1  instead of being disposed on the front side of the load port LP 1 . In other words, the manufacturing system  300  and the manufacturing system  1100  have different attachment positions of the buffer apparatus  230  to the load port LP 1 . 
         [0143]    In the second embodiment, in particular, in  FIG. 22 , the buffer apparatus  230  is constructed such that a length W 2  in the X direction of the load port P 21  (i.e. in the direction perpendicular to the orientation of the rail  1 ) is less than or equal to a length W 1  in the X direction of the load port LP 1 . Thus, for example, if there is an obstacle on the front side of the load port P 21  (i.e. in the X direction in  FIG. 21  and  FIG. 22 ), the buffer apparatus  230  can approach the manufacturing apparatus  20  from the orientation of the rail  1  (i.e. the right side in a Z direction in  FIG. 20  and  FIG. 21 ). Moreover, the buffer apparatus  230  can transfer the FOUP 3  from a position which is away on the right side in the Z direction of the load port LP 1 . Incidentally, the buffer apparatus  230  may be constructed such that the length W 2  of the load port P 21  is greater than or equal to the length W 1  of the load port LP 1 . In this case, for example, the side part of the buffer apparatus  230  protrude into the path in  FIG. 7 ; however, the protraction into the path can be significantly reduced, in comparison with the case where the buffer apparatus  230  is disposed on the front side of the load port LP 21 . 
         [0144]    In the second embodiment, preferably, in the buffer apparatus  230 , the width length Lw of the main body part  231  is less than or equal to the length W 1  in the X direction of the load port LP 1 , and for example, the buffer apparatus  230  can be disposed in a space which is made on the side of the load port LP 1  between the main body of the manufacturing apparatus  20  and the path without protruding into the path in  FIG. 7 . In  FIG. 21 , when the buffer apparatus  230  is attached to the load port LP 1 , it is displaced in the Z direction in the state that the OHT port P 21  is accommodated at the accommodation position (i.e. the state of a buffer mechanism  230 A in  FIG. 21 ), and it is disposed on the side surface side of the load port LP 1  which is the attachment target (i.e. the right side surface side of the load port LP 1  in  FIG. 21 ). Then, the buffer apparatus  230  is attached to the load port LP 1  in the state that the OHT port P 21  is displaced to the transfer position (i.e. the state of a buffer mechanism  230 B in  FIG. 21 ). At this time, the transfer mechanism  232  of the buffer apparatus  230  is disposed such that the longitudinal direction of a slide device  234  which can slide a holding device  233  matches the Z direction. 
         [0145]    When the buffer mechanism  230  is in the state of the buffer mechanism  230 B, for example, the holding device  233  is displaced in the Z direction toward to the load port LP 1  by the horizontal displacement mechanism  234 , and a pair of planar portions of the holding device  233  enters below the flange  3   a  of the FOUP 3  on the load port LP 1  and support the both ends of the flange  3   a  from below (i.e. hold the FOUP 3 ). In other words, in the second embodiment, the transfer mechanism  232  can displace the holding device  233  by the mutual operation of the horizontal displacement mechanism  234  and a hoist mechanism  235  described above, in the Z direction (i.e. one example of the “third direction” of the present invention) and the vertical direction (one example of the “second direction” of the present invention) among the load port LP 1 , the OHT port P 21 , and the buffer P 22 . 
         [0146]    According to the second embodiment, in the buffer apparatus  230 , the orientation of the rail  1  matches the Z direction (i.e. the third direction) in which the horizontal displacement mechanism  234  displaces the FOUP 3 , so that the buffer apparatus  230  can be also disposed on the side of the load port LP 1  (right beside in the second embodiment). As described above, if the buffer apparatus  230  is disposed on the side of the load port LP 1 , it is possible to effectively use the space which is made on the side of the load port LP 1 . On the other hand, the buffer apparatus  230  does not occupy the path at all, which is provided on the front side of the load port LP 1  in the manufacturing apparatus  20 , and the buffer apparatus  230  does not block a passage on the path at all. In other words, it is also possible to provide a narrow path in accordance with the arrangement of the buffer apparatus  230 . 
         [0147]    On the other hand, as described above, it is useful if the width length Lw of the main body part  231  is set to less than or equal to the length W 1  in the X direction of the load port LP 1 ; however, as shown in  FIG. 23 , it is also possible to set the width length Lw to greater than or equal to the length W 1  in the X direction of the load port LP 1 . In this case, in  FIG. 23 , if the buffer apparatus  330  is brought close to the manufacturing apparatus  20  in the Z direction, the main body part of the buffer apparatus  330  collides with the outer frame of the manufacturing apparatus  20  or the corner of the main body of the manufacturing apparatus  20 . In this case, however, it is not particularly problematic if the arrangement and size of the ports P 21  and LP 1  are constructed such that the OHT port P 21  is located above the load port LP 1  when or immediately before the buffer apparatus  330  collides with the corner of the main body of the manufacturing apparatus  20 . For example, it is useful if the load port LP 1  is provided as close to one corner on the front surface of the main body of the manufacturing apparatus  20  as possible (i.e. the right corner on the front surface of the manufacturing apparatus  20  in  FIG. 20  and  FIG. 21 ). Alternatively, in this case, the OHT port LP 21  and the transfer mechanism  232  may be able to extend in the horizontal direction (i.e. toward the left side in  FIG. 20  and  FIG. 21 ). Moreover, by making the OHT port LP 21  and the transfer mechanism  232  extendable, the buffer apparatus  330  can transfer the FOUP 3  with respect to the load port LP 2  located far away from the front surface of the manufacturing apparatus  20  (i.e. the load port on the left side in  FIG. 20  and  FIG. 21 ). 
         [0148]    In the manufacturing system  1100  provided with the buffer apparatus  230  in the second embodiment, it is possible to perform the same process as the first transfer operation process in  FIG. 4  or the second transfer operation process in  FIG. 5  by using a controller in the manufacturing system  1100 , with respect to the transfer operation between the vehicle  10  and the manufacturing apparatus  20  through the buffer apparatus  230  disposed on the side of the load port LP 1 , and it is also possible to quickly transfer the FOUP 3  with respect to the load port LP 1 , thereby improving the operating rate of the manufacturing apparatus  20 . Moreover, the buffer apparatus  230  can apply the positioning device (or positioning method), the fixing device (or fixing method), and the travelling device (or traveling method) in  FIG. 9  to  FIG. 19 , and the buffer apparatus  230  can be more stably disposed by the devices. 
         [0149]    Incidentally, the buffer apparatus in the second embodiment described above may be also constructed such that its height is equal to or greater than the height of a manufacturing apparatus, in response to the large-scaled manufacturing apparatus. In this case, as shown in  FIG. 24 , the buffer apparatus  430  is constructed, for example, such that a second OHT port P 40  can be disposed above an OHT port P 41  corresponding to the OHT port P 21  in  FIG. 20 . The second OHT port P 40  is displaced between a transfer position at which the FOUP 3  can be transferred with the vehicle  10  in the horizontal state and an accommodation position at which it is accommodated in a main body part  431  in the vertical state, as in the OHT port P 41 . For example, if the buffer apparatus  430  is disposed on the side surface side of the load port LP 1  (i.e. the right side in  FIG. 24 ), a transfer mechanism  432  is controlled by a controller in a manufacturing system  1200 , and the transfer mechanism  432  displaces a holding device  433  in the Z direction (i.e. one example of the “third direction” of the present invention) and the vertical direction (one example of the “second direction” of the present invention) among the aforementioned second OHT port P 40 , the OHT port P 41 , and the transfer mechanism  432  holds or releases the FOUP 3  on the holding device  433 , thereby transferring the FOUP 3  among them. 
         [0150]    Incidentally, the buffer apparatus  430  can be disposed not only on the side surface side of the load port LP 1  but also on the front side of the load port LP 1 , as in the buffer apparatus  30  in  FIG. 2  as shown in  FIG. 24 . For example, the main body part  431  of the buffer apparatus  430  is provided with a frame which is free of as much side surfaces as possible. In this case, when it is to dispose the buffer apparatus  430  on the front side of the load port LP 1 , the buffer apparatus  430  can be attached to the load port LP 1  such that one portion of the load port LP 1  (i.e. the front part of the load port LP 1 ) is located within the main body part  431 . By this, it is possible to dispose the buffer apparatus  430  closer to the main body of a manufacturing apparatus  420  in the X direction, and for example, it is possible to reduce the protrusion of the buffer apparatus  430  into the path in  FIG. 7 . 
         [0151]    The entire disclosure of Japanese Patent Application No. 2009-183310 filed on Aug. 6, 2009 including the specification, claims, drawings and summary is incorporated herein by reference in its entirety.

Technology Category: h