Abstract:
A double-seal mechanism is provided on a cover member for sealing closed a container main body. The double-seal mechanism includes an inner seal piece that seals an interior of the container main body and is positioned between an inner seal reception section of a flange of the container main body and a seal pressing section of the cover. An outer seal piece forms a second seal between the container main body and the periphery of the cover member. The inner seal piece has a rounded distal end fitted into a fitting groove in the flange. A cover member fixing unit of the cover member includes a latch shaft that is linearly projected from and retracted, a latch roller attached to a tip end of the latch shaft, and a crank mechanism that linearly projects and retracts the latch shaft as the crank mechanism rotates. The latch roller travels along an inclined retracting surface on the container main body which forces the cover member inward into sealing engagement with the container main body.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a thin film storage container which has an improved sealability for sealing a cover and a container main body and an improved detachability. 
   2. Description of the Related Art 
   Generally, there is known, as a thin film storage container, a container for storing and transporting semiconductor silicon wafers. As for the wafer storage and transport container, it is important to transport the container while keeping an interior of the container clean in order to prevent contamination of surfaces of the wafers contained therein. To this end, the interior of the container is sealed. That is, a cover member is fixed to a container main body, thereby sealing an interior of the container main body. The sealing of the cover member and the container main body is normally performed by providing a sealant between the cover member and the container main body. This sealant, which is attached to a peripheral edge of the cover member, and which elastically abuts against the container main body using a force of pressing the cover member against the container main body, seals the interior of the container main body. 
   Since the thin film storage container has a small gap between the cover member and the container main body, the sealant is substantially exposed to the outside. For this reason, a contaminant sometimes enters the container from the outside. This contaminant also enters into an abutment portion between the sealant and the container main body. If the cover member is attached to the container main body, the contaminant does not pose a serious problem. However, when the cover member is detached from the container main body, a problem occurs. Namely, when the cover member is detached from the container main body, an internal pressure of the container main body is temporarily negative, so that the outside air flows into the container main body from the gap formed in the abutment portion between the sealant and the container main body. If the contaminant enters the abutment portion between the sealant and the container main body, the contaminant disadvantageously enters the container main body. 
   SUMMARY OF THE INVENTION 
   The present invention has been achieved in light of the conventional disadvantages. It is an object of the present invention to provide a thin plate storage container capable of improving sealability for the sealing between a cover member and a container main body and improving a detachability of the cover member. 
   According to a first aspect of the present invention, there is provided a thin plate storage container comprising: a container main body which contains and supports a plurality of thin plates; a cover member which closes the container main body, and which keeps an interior of the container main body clean; and a double-seal mechanism that seals the interior of the container main body by the cover member, characterized in that the double-seal mechanism comprises: an inner seal piece attached to a peripheral edge of the cover member, abutting against the container main body, and thereby sealing the interior of the container main body; and an outer seal piece attached to an outside of the inner seal piece on the peripheral edge of the cover member, abutting against the container main body, and thereby sealing an abutment portion between the inner seal piece and the container main body. 
   With this constitution, the cover member is attached to the container main body, and the inner seal piece abuts against the container main body side, thereby sealing the inside and outside of the container main body from each other. The outer seal piece abuts on the container main body side, thereby covering the abutment portion between the inner seal piece and the container main body from the outside. It is, therefore, possible to prevent a contaminant from entering the abutment portion between the inner seal piece, which seals the inside and outside of the container main body from each other, and the container main body from the outside. As a result, even if the internal pressure of the container main body is temporarily negative when the cover member is detached from the container main body, the external air does not forcibly flow into the container main body from a gap in the abutment portion between the inner seal piece and the container main body since the outer seal piece covers the outside of the abutment portion therebetween. Furthermore, since no contaminant enters the abutment portion, it is possible to ensure preventing the contaminant from entering the container main body when the cover member is detached from the container main body. 
   According to a second aspect of the present invention, the thin plate storage container according to the first aspect of the present invention is characterized in that the inner seal piece is formed into an annular plate, and an inner end portion of the inner seal in a normal direction is supported by the cover member and extends outward in the normal direction, a seal pressing section that abuts against and presses the outside of the inner seal piece is formed annularly on an inner side surface of the peripheral edge of the cover member, and in that a seal reception section is formed annularly to be opposed to the seal pressing section, the seal reception section abutting against the inner seal piece, which is put between the seal reception section and the seal pressing section, from inside while the cover member is attached to the container main body. 
   With this constitution, since the inner seal piece is put between the inner seal reception section and the seal pressing section when the cover member is attached to the container main body, it is possible to ensure sealing the interior of the container main body. 
   According to a third aspect of the present invention, the thin plate storage container according to the first aspect of the present invention is characterized in that a bulge section is formed over an entire periphery of an outer end portion of the inner seal piece of the double-seal mechanism in the normal direction, and in that a fitting groove, into which the bulge section is fitted, is formed in the seal reception section of the container main body. 
   With this constitution, since the bulge section on the tip end of the inner seal piece is fitted into the fitting groove of the inner seal reception section of the container main body when the cover member is attached to the container main body, it is possible to ensure sealing the interior of the container main body. 
   According to a fourth aspect of the present invention, there is provided a thin plate storage container comprising: a container main body which contains and supports a plurality of thin plates; a cover member which closes the container main body, and which keeps an interior of the container main body clean; and cover member fixing means, provided at the cover member, for fixing the cover member to the container main body, characterized in that the cover member fixing means comprises: a latch shaft linearly projected from and retracted toward the cover member; and a latch roller rotatably attached to a tip end of the latch shaft, and in that a cover member retracting surface is provided on the container main body, the cover member retracting surface being formed to be inclined to be open outward toward the latch roller, abutting against the latch roller by extension of the latch shaft, and retracting the cover member toward the container main body while rotating. 
   With this constitution, the latch shaft of the cover member fixing means extends from the cover member, whereby the latch roller on the tip end of the latch shaft abuts against the cover member retracting surface of the roller reception hole of the container main body. If the latch shaft further extends in this state, the latch roller is forced into the cover member retracting surface while rotating. The cover member is thereby retracted into and fixed to the container main body. 
   According to a fifth aspect of the present invention, there is provided a thin plate storage container comprising: a container main body which contains and supports a plurality of thin plates; a cover member which closes the container main body, and which keeps an interior of the container main body clean; and cover member fixing means, provided at the cover member, for fixing the cover member to the container main body, characterized in that the cover member fixing means is comprised of a crank mechanism for projecting and retracting an engagement piece from and toward the cover member when rotating, the crank mechanism comprises: a rotary plate directly engaged with the engagement piece and rotating, thereby projecting and retracting the engagement piece; and a support piece supporting rotation of the rotary plate, and in that the support piece comprises: a pin reception section individually fitting and supporting a plurality of engagement pins provided on the rotary plate while extending the engagement piece from the cover member; and an elastic support section elastically supporting the plurality of pin reception sections, and adjusting the rotary plate to be located at a set angle at a set position. 
   With this constitution, while the engagement piece extends from the cover member, the pin reception section of the support piece individually fits and supports a plurality of engagement pins provided on the rotary plate. At this moment, the pin reception section is elastically supported by the elastic support section, and the support piece elastically supports the rotary plate and adjusts the rotary plate to be located at the set angle at the set position. Therefore, even if there is a slight positional deviation of the T-shaped tip end portions of the attachment/detachment arm of the attachment/detachment device relative to the thin plate storage container, the deviation can be absorbed by causing the support piece to elastically support the rotary plate. 
   According to a sixth aspect of the present invention, the thin plate storage container according to any one of the first to fifth aspects of the present invention is characterized by comprising: a small hole provided in the container main body; a filter which permits pass of only the air between an inside and an outside of the container main body, and which removes a contaminant; and a cover provided outside of the filter. 
   With this constitution, even if the thin plate storage container is moved or put at various locations, it is possible to prevent the filter from contacting with something and being damaged. 
   According to a seventh aspect of the present invention, the thin plate storage container according to any one of the first to sixth aspects of the present invention is characterized in that, at an uppermost position of a thin plate support section comprising comb&#39;s teeth that support the plurality of thin plates contained in the container main body at certain intervals, respectively, an additional comb&#39;s tooth for supporting another thin plate is provided. 
   With this constitution, one comb&#39;s tooth for supporting another thin plate is further provided at the upper post position and the unnecessary semiconductor silicon wafer is used as a cover for the uppermost semiconductor silicon wafer. It is thereby possible to prevent the contaminant or the like from adhering to the uppermost semiconductor silicon wafer. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an important part cross-sectional view which illustrates a cover member reception section of a semiconductor silicon wafer storage container according to the present invention; 
       FIG. 2  is a perspective view which illustrates the silicon wafer storage container according to the present invention; 
       FIG. 3  is a perspective view which illustrates the silicon wafer storage container according to the present invention; 
       FIG. 4  is an important part cross-sectional view which illustrates the cover member reception section of the silicon wafer storage container according to the present invention; 
       FIG. 5  is an important part cross-sectional view which illustrates the cover member reception section of the silicon wafer storage container according to the present invention; 
       FIG. 6  is an important part cross-sectional view which illustrates the cover member reception section of the silicon wafer storage container according to the present invention; 
       FIG. 7  is an important part perspective view which illustrates a crank mechanism of cover member fixing means; 
       FIG. 8  is an important part perspective view which illustrates the crank mechanism of the cover member fixing means; 
       FIG. 9  is a perspective view which illustrates a support piece of the crank mechanism of the cover member fixing means; 
       FIG. 10  is an important part perspective view which illustrates the crank mechanism of the cover member fixing means; 
       FIG. 11  is a perspective view which illustrates a filter; 
       FIG. 12  is a cross-sectional view which illustrates the semiconductor silicon wafer storage container; and 
       FIG. 13  is a perspective view which illustrates a modification of the semiconductor silicon wafer storage container according to the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   An embodiment of the present invention will be described hereinafter with reference to the accompanying drawings. 
   This embodiment will be described, while taking a semiconductor silicon wafer storage container for storing and transporting, as thin plates, semiconductor silicon wafers as an example. 
   As shown in  FIGS. 2 ,  3 , and  12 , the semiconductor silicon wafer storage container  1  includes a container main body  2  which stores and supports many semiconductor silicon wafers S inside, wafer support sections  3  which are provided on opposed sidewalls in the container main body  2 , respectively, and each of which serves as a thin plate support section for holding the many semiconductor silicon wafers S contained in the container main body  2  one piece by one piece from both sides at certain intervals, and a cover member  4  which airtight closes an opening portion of the container main body  2  and which keeps an interior of the container  1  clean. 
   The entire container main body  2  is generally formed into a cube. The wafer support section  3  is attached to an inside of each sidewall of the container main body  2 . 
   A transport flange section  7  is provided on an end wall on one side (an upper side in  FIG. 12 ) of the container main body  2 . The transport section  7  is gripped by an arm of a transport device (not shown) provided on a production line or the like when the transport device transports the container  1 . As shown in  FIG. 2 , positioning fitting sections  8  are provided on an end wall on the other side of the container main body so as to accurately adjust a mounting position of the container  1 . 
   Handles  9  are provided on the both sidewalls of the container main body  2 , respectively so that an operator can hold the container main body  2  with operator&#39;s hands to carry the container  1  and can put the container  1  vertically. 
   A cover member reception section  11  is provided on a front end portion (a left end portion in  FIG. 12 ) of the container main body  2  so as to fit the cover member  4  into the container main body  2 . AS shown in  FIGS. 1 ,  4 ,  5 , and  6 , this cover member reception section  11  is formed by enlarging the end portion of the container main body  2  so as to be adjusted to the cover member  4 . This cover member reception section  11  is formed into two steps so as to be suited to a double-seal mechanism  65  to be described later. Specifically, the cover member reception section  11  is comprised of an inner step  12  and an outer step  13 . 
   The inner step  12  is formed to be widened from a front end of the sidewall of the container main body  2  toward an outer periphery of the container main body  2 . This inner step  12  constitutes an inner seal reception section  15  on which an inner seal piece  66  of the double-seal mechanism  65  abuts. A fitting groove  16 , into which a bulge section  66 C on a tip end of the inner seal piece  66  is fitted, is formed in the inner seal reception section  15 . The inner step  12  is extended to constitute a grip flange  17 . The grip flange  17  is a flange gripped by the operator when the transport device transports the container main body  2 . 
   The outer step  13  is formed on an outside (a right side shown in  FIG. 1 ) of the inner step  12  so as to be deviated by as much as a thickness of the cover member  4 . This outer step  13  constitutes an outer seal reception section  18  on which an outer seal piece  67  of the double-seal mechanism  65  abuts. 
   Roller reception holes  21  are provided between the inner step  12  and the outer step  13 . The roller reception holes  21  are provided at four positions corresponding to respective latch rollers  42  to be described later. Each roller reception hole  21  is set to have a size enough to contain the corresponding latch roller  42 . An outer side surface  22  of the roller reception hole  21  is comprised of a cover member supporting surface  22 A and a cover member retracting surface  22 B. The cover member supporting surface  22 A, which is formed horizontally,(vertically), is abutted by the corresponding latch roller  42  with the latch roller  42  completely fitting into the roller reception hole  21 , thereby fixedly supporting the cover member  4  on the container main body  2 . The cover member retracting surface  22 B is formed to be inclined so as to be open outward to the corresponding latch roller  42 . By so forming, the cover member retracting surface  22 B directly presses the latch roller  42  and indirectly presses the cover member  4  against the container main body  2 . Namely, when the latch roller  42  enters the roller reception hole  21  in response to the extension of a latch shaft  41  to be described later, the latch roller  42  abuts against the cover member retracting surface  22 B, moves deep into an inclined face of the cover member retracting surface  22 B while rotating. Thus, the cover member  4  is retracted toward the container main body  2 , as seen in state transition from a state shown in  FIG. 1  to a state shown in  FIG. 6 . Another step  24  is provided around the outer step  13  to thereby form an outer end face  25  of the container main body  2 . The outer end face  25  of the container main body  2  is set to be flush with an outer end face of the cover member  4  while the latch roller  42  abuts against the cover member supporting surface  22 A of the roller reception hole  21  and the cover member  4  is attached to the container main body  2 . 
   As shown in  FIGS. 1 to 6 , the cover member  4  is formed into a hollow thick plate. Specifically, the cover member  4  is comprised of a shallow plate-like main body section  27  and a cover plate section  28  that closes the main body section  27 . An inner gasket support groove  29  and an outer gasket support groove  30  are provided on a peripheral edge of the plate-like main body section  27 . 
   The inner gasket support groove  29  is formed annularly on an inner side surface (a left side surface in  FIG. 1 ) of a peripheral edge of the main body section  27 . The inner seal piece  66  having a L-shaped cross section to be described later is extended outward in a normal direction while a proximal end portion of the seal piece  66  is fitted into and supported by the inner gasket support groove  29 . On the inner side surface (left side surface in  FIG. 1 ) of the peripheral edge of the main body section  27 , a seal pressing section  32  that abuts against and presses an outer side surface of the inner seal piece  66  is formed annularly outward in the normal direction of the inner gasket support groove  29 . This seal pressing section  32  presses the outer side surface of the inner seal piece  66 , whereby the inner seal piece  66  is put between the seal pressing section  32  and the inner seal reception section  15  of the container main body  2 . 
   The outer gasket support groove  30  is formed annularly on an outer portion (a right portion in  FIG. 1 ) of the peripheral edge of the main body section  27 . This outer gasket support groove  30  is constituted as an annular groove that is open outward in the normal direction. An outer wall  30 A of the outer gasket support groove  30  is formed to be enlarged so as to cover and protect the outer seal piece  67 . 
   Shaft holes  34  are provided at four positions, respectively between the inner gasket support groove  29  and the outer gasket support groove  30 . Each of the shaft hole  34  is intended to slidably support the latch shaft  41  to be described later. A bearing  35  is attached to each shaft hole  34 . This bearing  35  is set to be substantially equal in size to a roller support section  41 B of the latch shaft  41  so as not to generate an excessively large gap in a sliding portion. This is intended to prevent a contaminant or the like from entering the inner seal piece  66  even if the contaminant is generated in the main body section  27 . 
   As shown in  FIGS. 1 and 5  to  10 , cover member fixing means  37  is provided in the main body section  27  so as to fix the cover member  4  to the container main body  2 . This cover member fixing means  37  is comprised of an engagement piece  38  and a crank mechanism  39 . 
   The engagement piece  38  is comprised of the latch shaft  41  and the latch roller  42 . The latch shaft  41  is a shaft that is linearly projected from and retracted toward the main body section  27  of the cover member  4 . The latch shaft  41  is comprised of a metallic rod section  41 A, the roller support section  41 B, and a crank engagement section  41 C. The metallic rod section  41 A is a member that maintains the strength of the latch shaft  41 . The roller support section  41 B, which is made of a synthetic resin, is slidably inserted into the bearing  35  of the main body section  27  and supports projective and retractive movements of the latch shaft  41 . The crank engagement section  41 C is a member engaged with a projection/retraction elongated hole  47  of a rotary plate  45  to be described later. An engagement pin  41 D fitted into the projection/retraction elongated hole  47  of the rotary plate  45  is provided on a tip end portion of the crank engagement section  41 C. 
   The latch roller  42  is a member for abutting the cover member  4  against the container main body  2  and fixing the cover member  4  to the container main body  2  without friction. This latch roller  42  is rotatably attached to a tip end of the roller support section  41 B. 
   The crank mechanism  39  is a member for allowing the engagement piece  38  to be projected from or retracted toward the cover member  4  when the crank mechanism  38  rotates. This crank mechanism  39  is comprised of the rotary plate  45  and a support piece  46 . 
   The rotary plate  45  is a member which is engaged with the engagement piece  38  and which allows the engagement piece  38  to be projected from or retracted toward the cover member  4  when the rotary plate  45  rotates. The rotary plate  45  is formed into a disk and provided with two projection/retraction elongated holes  47  helically extending toward a center of the rotary plate  45 . The crank engagement section  41 C of the latch-shaft  41  is engaged with each projection/retraction elongated hole  47 , and attracted toward the center of the rotary plate  45  or forced toward a peripheral edge of the rotary plate  45 , thereby projecting or retracting the engagement piece  38 . A fitting recess  49  is provided at a core on a surface of the rotary plate  45 . This fitting recess  49  is formed to be depressed by protruding surroundings of the recess  49 . The fitting recess  49  is a portion into which a T-shaped tip end portion of an attachment/detachment arm of a cover member attachment/detachment device (not shown) is fitted. 
   On a rear surface of the rotary plate  45 , engagement pins  51  are provided at three positions, respectively. Each of the engagement pins  51  is a member, engaged with the support piece  46  to be described later, for adjusting a position and an angle of the rotary plate  45 . A rotary shaft  52  is provided at a center of the rear surface of the rotary plate  45 . 
   The support piece  46  is a member for supporting the rotation of the rotary plate  45 . The support piece  46  is comprised of U-shaped fixing sections  54 , pin reception sections  55 , an elastic support section  56 , and a rotary shaft hole  57 . 
   The U-shaped fixing sections  54  are members for fixing the support piece  46  to the cover member  4 . The U-shaped fixing sections  54  are provided at three positions around the rotary shaft hole  57 , and attached to fixing tools  59  of the cover member  4 , respectively, thereby fixing the support piece  46  to the side of the cover member  4 . 
   The pin reception sections  55  are members for supporting the rotary plate  45  at a set angle. Namely, while the engagement piece  38  is extended from the cover member  4 , the engagement pins  51  of the rotary plate  45  are fitted into and supported by the respective pin reception sections  55 , whereby the pin reception sections  55  support the rotary plate  45  at the set angle at a set position. The pin reception sections  55  are formed into V shape and engaged with the engagement pins  51 , respectively. The pin reception sections  55  are provided at three positions corresponding to the engagement pins  51  provided at the three positions on the rear surface of the rotary plate  45 , respectively. 
   The elastic support section  56  is a member for elastically supporting the respective pin reception sections  55 . The elastic support section  56  is made of a rod material spanning between tip ends of the adjacent U-shaped fixing sections  54 . This elastic support section  56  has elasticity, so that the elastic support section  56  elastically supports the pin reception sections  55  by tip end portions thereof while proximal end portions are supported by the respective U-shaped fixing sections  54 . The elastic support section  56  thereby elastically supports the respective pin reception sections  55  at set positions, adjusts the rotary plate  45  to be located at its set angle at its set position through the engagement pins  51  engaged with the respective pin reception sections  55 , and thereby supports the rotary plate  45 . Reference symbols  60  and  61  denote stoppers that restrict the rotation of the rotary plate  45 . By abutting the engagement pins  51  against the stoppers  60  and  61 , the unnecessary rotation of the rotary plate  45  is restricted. 
   The rotary shaft hole  57  is a member for supporting the rotation of the rotary plate  45 . An inside diameter of the rotary shaft hole  57  is set slightly larger than an outside diameter of the rotary shaft  52  of the rotary plate  45 , thereby providing the rotary plate  45  with play. Even if the semiconductor silicon wafer storage container  1  is slightly deviated from the T-shaped tip end portions of the attachment/detachment arm of the cover member attachment/detachment device, this play can absorb the deviation. 
   The two cover member fixing means  37  are provided respectively at two positions in the main body section  27 , to enable the four engagement pieces  38  to be projected from and retracted toward neighborhoods of four corners of the cover member  4 , respectively. 
   The cover plate section  28  is a member that covers and closes the main body section  27  including the cover member fixing means  37 . The cover plate section  28  is formed into a rectangular plate, and provided with elongated holes  63  into which the T-shaped tip end portions of the attachment/detachment arm of the attachment/detachment device are inserted, respectively. The elongated holes  63  are provided at two positions to correspond to the engagement pieces  38  of the two cover member fixing means  37  provided in the main body section  27 , respectively. By providing the elongated holes  63 , the two T-shaped tip end portions of the attachment/detachment arm of the attachment/detachment device are inserted into the elongated holes  63 , and fitted into the fitting recesses  49  of the cover member fixing means  37  provided in the main body section  27 , respectively. 
   The double-seal mechanism  65  that seals the interior of the container main body  2  is provided on the peripheral edge of the cover member  4 . This double-seal mechanism  65  is comprised of the inner seal piece  66  and the outer seal piece  67 . 
   The inner seal piece  66  is a member that seals the interior of the container main body  2 . This inner seal piece  66  is attached to the peripheral edge of the cover member  4 , and abuts against the container main body  2 , thereby sealing the interior of the container main body  2 . The inner seal piece  66  is formed into a generally annular plate having an L-shaped cross section. The inner seal piece  65  is comprised of a support section  66 A which is fitted into the inner gasket support groove  29  of the cover member  4 , and an extension section  66 B which is put between the container main body  2  and the cover member  4  and which seals the interior of the container main body  2 . The support member  66 A is fitted into the inner gasket support groove  29  of the cover member  4 , whereby the inner seal piece  66  is supported by the cover member  4 . While the support section  66 A is fitted into the inner gasket support groove  29  of the cover member  4 , the extension section  66 B is provided to extend outward in the normal direction. The extension section  66 B is provided to cover the seal pressing section  32  while being provided to extend outward in the normal direction. The bulge section  66 C fitted into the fitting groove  16  is formed on a tip end of the extension section  66 B. The bulge section  66 C is formed by expanding the tip end of the extension section  66 B so as to have a circular cross section. 
   The outer seal piece  67  is a member that seals the abutment portion between the inner seal piece  66  and the container main body  2 . This outer seal piece  67  is formed into a generally annular plate, and fitted into the outer gasket support groove  30 . The outer seal piece  67  is thereby attached to cover an outside of the inner seal piece  66 . The outer seal piece  67  is comprised of a proximal fitting section  67 A and a distal abutment section  67 B. The proximal fitting section  67 A is fitted into the outer gasket support groove  30  of the cover member  4 , and supports the outer seal piece  67  toward the cover member  4 . The distal abutment section  67 B abuts against the outer step  13  of the container main body  2 , thereby sealing the abutment portion between the inner seal piece  66  and the inner seal reception section  15  of the container main body  2 . 
   As shown in  FIG. 4 , wafer pressers  71  are attached to an inner surface of the cover member  4 . 
   As shown in  FIGS. 2 and 11 , a small hole (not shown) is formed on a mount surface of the container main body  2 , and a filter  72  is attached to the small hole. This filter  72  is a member that removes the contaminant or the like between inside and outside of the container main body  2  and that permits only the air to enter the container main body  2 . A cover  73  for protecting the filter  72  is provided outside of the filter  72 . This cover  73  is comprised of an annular section  74  covering surroundings of the filter  72  and radial protection arm sections  75  extending from this annular section  74  toward a center of the cover  73 . 
   As shown in  FIG. 12 , each of the wafer support sections  3  attached into the container main body  2  includes many comb&#39;s teeth  5  that are arranged in parallel at certain intervals and that support the semiconductor silicon wafers S at certain intervals, respectively. Since the number of the semiconductor silicon wafers S supported in the container main body  2  is fixed according to a standard, so that the number of the comb&#39;s teeth  5  is fixed, accordingly. The comb&#39;s tooth  5  corresponding to one semiconductor silicon wafer S is further provided on the uppermost comb&#39;s tooth  5 . This is intended to protect the uppermost semiconductor silicon wafer S. Namely, the contaminant or the like often adheres to an upper side surface of the uppermost semiconductor silicon wafer S among a plurality of semiconductor silicon wafers S contained in the container  1 . Therefore, if an unnecessary semiconductor silicon wafer S is stored in the container  1  to be put on the upper side surface of the uppermost semiconductor silicon wafer S, the contaminant or the like adheres to the unnecessary semiconductor silicon wafer S, making it possible to prevent the contaminant or the like from adhering to the uppermost semiconductor silicon wafer S. 
   [Function] 
   The semiconductor silicon wafer storage container  1  constituted as stated above is used as follows. 
   In order to contain the semiconductor silicon wafers S in the container main body  2 , the two T-shaped tip end portions of the attachment/detachment arm of the cover member attachment/detachment device are inserted first into the respective elongated holes  63 , and fitted into the fitting recesses  49  of the rotary plate  45  of the cover member fixing means  37 . At this moment, the rotary plate  45  is elastically supported by the support piece  46  to be adjusted to be located at the set angle at the set position. Therefore, the T-shaped tip end portions are smoothly fitted into the fitting recesses  49  without contacting with the recesses  49 . While being fitted into the fitting recesses  49 , the T-shaped tip end portions are rotated and the latch roller  42  is retracted toward the cover member  4  through the latch shaft  41 . As a result, the latch roller  42  is detached from the roller reception hole  21 , the cover member  4  is unfixed from the container main body  2 , and the cover member attachment/detachment device detaches the cover member  4  from the container main body  2 . 
   Next, the semiconductor silicon wafers S are installed into the container main body  2  by the transport device. In this case, after the semiconductor silicon wafers S of a set number are installed, the unnecessary semiconductor silicon wafer S that may be contaminated with the contaminant or the like is provided on an uppermost position. 
   The cover member attachment/detachment device attaches the cover member  4  to the container main body  2 . Specifically, the cover member  4  is inserted into the cover member reception section  11  of the container main body  2 , and the rotary plate  45  of the cover member fixing mean  37  is rotated. As a result, the latch shaft  41  extends outward from the cover member  4 , and the latch roller  42  abuts on the cover member retracting surface  22 B of the roller reception hole  21 . The latch roller  42  is further forced inside while abutting on the retracting surface  22 B. The latch roller  42  is forced even into the cover member supporting surface  22 A while press-contacting the cover member retracting surface  2 B, whereby the cover member  4  is retracted toward and fixed as seen in the state transition from the state shown in  FIG. 1  to the state shown in  FIG. 6 . Accordingly, the inner seal piece  66  of the double-seal mechanism  65  abuts against the inner seal reception section  15 , and the outer seal piece  67  thereof abuts against the outer seal reception section  18 . Further, the bulge section  66 C of the inner seal piece  66  is fitted into the fitting groove  16 , and the extension section  66 B is put between the inner seal reception section  15  and the seal pressing section  32 , thereby ensuring sealing the interior of the container main body  2 . In addition, by causing the outer seal piece  67  to abut against the outer seal reception section  18 , the abutment portion between the inner seal piece  66  and the inner seal reception section  15  is sealed, thereby preventing the contaminant or the like from entering the abutment portion between the inner seal piece  66  and the inner seal reception section  15  from the outside during transport. 
   In this state, the fitting recess  49  of the rotary plate  45  is matched to each elongated hole  63 , and the T-shaped tip end portions are pulled out as they are. The semiconductor silicon wafer storage container  1  is then transported to a predetermined location. 
   During the transport, even if the contaminant or the like floats around the semiconductor silicon wafer storage container  1 , the contaminant or the like does not enter the abutment portion between the inner seal piece  66  and the inner seal reception section  15  since the outer seal piece  67  abuts on the outer seal reception section  18 . 
   In order to detach the cover member  4  from the container main body  2  at a destination, the two T-shaped tip end portions of the attachment/detachment arm of the cover-member attachment/detachment device are inserted into the respective elongated holes  63 , and fitted into the fitting recesses  49  of the rotary plate  45  of the cover fixing means  37 . At this moment, the rotary plate  45  is elastically supported by the support piece  46  to be adjusted to be located at the set angle at the set position. Therefore, the T-shaped tip end portions are smoothly fitted into the fitting recesses  49  without contacting with the recesses  49 . While being fitted into the fitting recesses  49 , the T-shaped tip end portions are rotated and the latch roller  42  is retracted toward the cover member  4  through the latch shaft  41 . As a result, the latch roller  42  is detached from the roller reception hole  21 , the cover member  4  is unfixed from the container main body  2 , and the cover member attachment/detachment device detaches the cover member  4  from the container main body  2 . 
   When detaching the cover member  4  from the container main body  2 , the internal pressure of the container main body  2  becomes instantaneously negative. Due to this, even if the air outside of the inner seal piece  66  flows into the container main body  2 , the contaminant or the like is hardly present in the abutment portion between the inner seal piece  66  and the inner seal reception section  15 , thereby preventing the contaminant or the like from entering the container main body  2 . 
   Although the semiconductor silicon wafer storage container  1  is mounted at various locations during transport, the container  1  is not damaged since the cover  73  is provided on the filter  72 . 
   [Advantages] 
   As stated so far, since the storage container  1  includes the double-seal mechanism  65 , it is possible to ensure preventing the contaminant from entering the container main body  2  when the cover member  4  is detached from the container main body  2 . 
   Since the inner seal piece  66  is put between the inner seal reception section  15  and the seal pressing section  32 , it is possible to ensure sealing the interior of the container main body  2 . 
   Since the bulge section  66 C on the tip end of the inner seal piece  66  is fitted into the fitting groove  16  of the inner seal reception section  15  of the container main body  2 , it is possible to ensure sealing the interior of the container main body  2 . 
   The latch shaft  41  of the cover member fixing means  37  extends from the cover member  4 , and the latch roller  42  on the tip end of the latch shaft  41  abuts against the cover member retracting surface  22 B of the roller reception hole  21  of the container main body  2  and is forced inside while rotating, whereby the cover member  4  is retracted toward the container main body  2 . It is, therefore, possible to ensure fixing the cover member  4  to the container main body  2 . 
   The support piece  46  elastically supports the rotary plate  45  and adjusts the rotary plate  45  to be located at the set angle at the set position. Therefore, even if there is a slight positional deviation of the T-shaped tip end portions of the attachment/detachment arm of the attachment/detachment device relative to the semiconductor silicon wafer (thin plate) storage container, the deviation can be absorbed and the cover member  4  can be detached from the container main body  2  smoothly. 
   The cover  73  is provided outside of the filter  72 . Therefore, even if the semiconductor silicon wafer (thin plate) storage container  1  is moved or put at various locations, it is possible to prevent the filter  72  from contacting with something and being damaged. 
   Since the unnecessary semiconductor silicon wafer S is used as a cover for the uppermost semiconductor silicon wafer S, it is possible to prevent the contaminant or the like from adhering to the uppermost semiconductor silicon wafer S. 
   [Modification] 
   
       
       (1) In the embodiment, the example of using the semiconductor silicon wafer S as the thin plate has been described. However, the thin plate is not limited to the semiconductor silicon wafer S but may be any thin plate, such as a liquid crystal glass plate or a storage disk, which may possibly be adversely influenced by gas, fine particles, and the like. 
       (2) In the embodiment, the elastic support section  56  of the support piece  46  is connected to the adjacent U-shaped fixing sections  54 . Alternatively, the elastic support section  56  may be formed into another shape so as to secure necessary elasticity. For example, as shown in  FIG. 13 , an elastic support section  56 A may be cut off halfway so as to secure higher elasticity. 
     
  
   As stated so far in detail, the storage container of the present invention exhibits the following advantages. 
   Since the storage container includes the double-seal mechanism, it is possible to ensure preventing the contaminant from entering the container main body when the cover member is detached from the container main body. 
   Since the inner seal piece is put between the inner seal reception section and the seal pressing section, it is possible to ensure sealing the interior of the container main body. 
   Since the bulge section on the tip end of the inner seal piece is fitted into the fitting groove of the inner seal reception section of the container main body, it is possible to ensure sealing the interior of the container main body. 
   The latch shaft of the cover member fixing means extends from the cover member, and the latch roller on the tip end of the latch shaft abuts against the cover member retracting surface of the roller reception hole of the container main body and is forced into the surface while rotating, whereby the cover member is retracted into the container main body. It is, therefore, possible to ensure fixing the cover member to the container main body. 
   The support piece elastically supports the rotary plate and adjusts the rotary plate to be located at the set angle at the set position. Therefore, even if there is a slight positional deviation of the T-shaped tip end portions of the attachment/detachment arm of the attachment/detachment device relative to the thin plate storage container, the deviation can be absorbed and the cover member can be detached from the container main body smoothly. 
   The cover is provided outside of the filter. Therefore, even if the thin plate storage container is moved or put at various locations, it is possible to prevent the filter from contacting with something and being damaged. 
   Since the unnecessary semiconductor silicon wafer is used as a cover for the uppermost semiconductor silicon wafer, it is possible to prevent the contaminant or the like from adhering to the uppermost semiconductor silicon wafer.