Abstract:
The present invention was developed in order to provide a disc player, whereby even when an inserted disc is not normally set on a stocker, or a normally set disc is dislocated from a stocker, the disc can be reset in the normal position on the stocker during a stocker lifting/division operation, so that the normal operating condition can be quickly recovered without troublesome removing activities, comprising multiple stockers for stocking discs and a lifting division device to conduct the lifting/division of these stockers, wherein disc guides for controlling the movement of a disc unexpectedly dislocated from a stocker are mounted.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a disc player and, more particularly, to a disc player which can reproduce information recorded in discs such as compact discs (CDs) and DVDs (Digital Versatile Discs). 
   2. Description of the Relevant Art 
     FIG. 26  is a sectional side view schematically showing the construction of a mobile disc player having an autochanger function disclosed in Japanese Kokai No. 2000-48462. A housing  51  constituting a disc player  50  comprises a main chassis  52 . At the front of the disc player  50 , a front panel  54  with a disc insert/eject slot  54   a  for insertion and ejection of a disc  53  formed thereon is mounted. 
   Above the forward portion of the main chassis  52 , a mount chassis  60 , which can be displaced up and down by engagement thereof with turntable lifting slide plates (not shown) slidably mounted on the sidewalls of the main chassis  52 , is arranged. 
   On the mount chassis  60 , a floating chassis  62  is arranged through a floating mechanism  61  comprising a locking member  61   a , a locking shaft  61   b  and spring parts  61   c . With the floating mechanism  61 , the influence of vibration or shock applied from the outside during reproduction can be reduced. 
   On the floating chassis  62 , a slide chassis  63  is mounted in such a manner as to be slidable in a back-and-forth direction relative to the floating chassis  62 . On the slide chassis  63 , a swing board  66  swingable in an arc, on which a turntable unit  64  having a turntable  64   a , and a pickup unit (hereinafter, referred to as a PU unit)  65  are mounted, is placed. 
   Above the swing board  66 , an insert/eject mechanism  73  comprising a disc supporting plate  70  for supporting the disc  53 , an insert/eject roller  71  for moving the disc  53  supported by the disc supporting plate  70  backward and forward, and a shutter section  72  whereby the disc insert/eject slot  54   a  is opened or closed, are arranged. With the insert/eject mechanism  73 , the insertion/ejection operation of the disc  53  can be conducted. 
   At prescribed places in the rearward portion of the main chassis  52 , a couple of lifting guides  55  are vertically mounted. On the main chassis  52 , a stocker bottom board  80 , six stockers  81  for setting discs  53  thereon, and a stocker top board  82  for retaining the surface of a disc  53  set on the uppermost stocker  81  in ascending order, are laminated with the lifting guides  55  inserted through insertion holes (not shown) arranged in each of them. 
   The stocker bottom board  80  is in engagement with lifting slide plates  56  slidably mounted on the sidewalls of the main chassis  52  in a manner whereby it moves up and down with the movement of the lifting slide plates  56 . 
   The stockers  81  are in engagement with division slide plates  57  slidably mounted on the sidewalls of the main chassis  52  in a manner whereby they are divided into the upper and lower parts with the movement of the division slide plates  57 . In insertion, ejection, reproduction or the like of a disc  53 , a prescribed space is formed by the division so that the PU unit  65  can approach the disc  53 . Drive motors (not shown) as driving forces for slidably driving these turntable lifting slide plates, lifting slide plates  56  and division slide plates  57  are arranged in two corners of the rear of the main chassis  52 . 
   On both side portions of the stocker top board  82 , hooks (not shown) for hooking coil springs (not shown) are formed. One end of a slender coil spring is caught with the hook, while the other end thereof is caught with a hook (not shown) arranged near the center of the stocker bottom board  80 . With these coil springs, the overall stockers  81  are energized for being closer, even if the stockers  81  are under divided conditions or all of them are set close. 
   A control circuit  90 , conducting driving control of each section, which is mounted on a substrate, is arranged on the outside wall of the main chassis  52 . 
     FIG. 27  comprises diagrams schematically showing the construction of the stocker  81 , wherein  FIG. 27(   a ) is a perspective view, while  FIG. 27(   b ) is an enlarged fragmentary view showing an antifloating claw. 
   The stocker  81  comprises a periphery  81   a  formed in the shape of an almost semicircular arc so as to surround the outer regions of a disc  53 , and a narrow disc receiver  81   b  for supporting the outer regions of the disc  53 . In the rear portion of the periphery  81   a , antifloating claws  81   c  for preventing the disc  53  set on the disc receiver  81   b  from floating upward are formed. The antifloating claw  81   c  is formed so as to be inwardly convex from the inner wall surface of the periphery  81   a  with a claw portion  81   e  having a slightly tapered plane  81   d  formed thereon. 
   In both side portions of the periphery  81   a , division projections  81   f  for lifting/division by engagement with the division slide plates  57 , and a couple of insertion holes  81   g  for inserting the lifting guides  55  therethrough are formed. In both end portions of the periphery  81   a , dislocation preventive projections  81   h  for preventing the dislocation of the stockers  81  when they are put in piles are formed. 
   The main operation of the conventional disc player  50  is described below. 
     FIG. 28  comprises simplified side views showing the operation of the conventional disc player  50 , which illustrate the insertion operation of a disc  53 . 
     FIG. 28(   a ) shows an insertion standby state where the disc  53  can be inserted. With the insert/eject roller  71  being lowered, the insert/eject mechanism  73  is in a state of being capable of pulling in the disc  53  to be inserted. 
   When the fifth stocker  81  from the bottom (hereinafter, referred to as the fifth stocker) is selected as a stocker on which the disc  53  is set, the first to fourth stockers  81  are kept close, while the fifth stocker is caused to ascend so that the turntable unit  64  can enter between the fourth and fifth stockers. 
   The upper stocker thereabove (the sixth stocker in this case) is caused to move further upward so that the disc  53  can be carried into the space between the selected fifth stocker and the sixth stocker. The turntable unit  64  is on standby at a prescribed standby position in order to hold the inserted disc  53  on the turntable  64   a  and carry it to the stocker  81  side. 
     FIG. 28(   b ) shows a state where one disc  53  is inserted in the disc insert/eject slot  54   a . The insert/eject roller  71  of the insert/eject mechanism  73  is driven to once pull the inserted disc  53  into the interior of the system, and then the shutter section  72  is closed ( FIG. 28(   c )). 
   Then, the disc  53  is conveyed in the reverse direction and the positioning thereof is conducted at a place where it is brought into engagement with the shutter section  72  ( FIG. 28(   d )). To the disc  53  located in  FIG. 28(   d ), the turntable unit  64  is caused to ascend, and the disc  53  is placed on the turntable  64   a . By operating a catching mechanism (not shown) of the turntable unit  64 , the disc  53  is clamped to the turntable  64   a  ( FIG. 28(   e )). 
   By sliding the slide chassis  63  to the stocker  81  side, the turntable unit  64  is horizontally moved so as to pull the disc  53  out of the insert/eject mechanism  73  and move it between the fifth and sixth stockers  81  ( FIG. 28(   f )). After moving the disc  53  to the reproduction position, the locking shaft  61   b  fixed with the locking member  61   a  is released, so that the turntable unit  64  is made in a state of mechanically floating with the floating mechanism  61 . The turntable  64   a  is rotatably driven so as to reproduce the disc  53  ( FIG. 28(   g )). 
     FIG. 29  comprises simplified side views for illustrating the changing operation of a disc to be reproduced of the conventional disc player  50 . 
     FIG. 29(   a ) shows a state of reproducing the fifth disc  53  from the bottom in the similar condition to that of  FIG. 28(   g ). When the user gives a command to reproduce the fourth disc  53  in this state, the locking shaft  61   b  is fixed with the locking member  61   a , so that the floating state of the turntable unit  64  is cleared. The turntable lifting slide plates and the division slide plates  57  are caused to slide, the turntable unit  64  and the fifth stocker  81  on which the disc  53  was previously set are caused to rise, and the disc  53  is set on the disc receiver  81   b  of the fifth stocker  81 . 
   The catching mechanism of the turntable unit  64  is activated so as to clear the state of clamping the disc  53  ( FIG. 29(   c )). Then, the turntable unit  64  is moved downward and the disc  53  is taken from the turntable  64   a  onto the fifth stocker  81  ( FIG. 29(   d )). 
   The turntable unit  64  is horizontally moved to under the insert/eject mechanism  73  ( FIG. 29(   e )), and then, all the divided stockers  81  are caused to descend, so that all the stockers  81  are piled up, resulting in reset of the divided state ( FIG. 29(   f )). 
   In the state of all the stockers  81  in piles, the stockers  81  are divided into the upper part including the selected fourth stocker  81  and the stockers  81  thereabove, and the lower part constituted of the stockers  81  below the selected fourth stocker  81  ( FIG. 29(   g )). The turntable unit  64  is moved into the space between the third and fourth stockers  81  ( FIG. 29(   h )). 
   The turntable unit  64  is moved upward, a disc  53  to be reproduced is placed on the turntable  64   a , and the catching mechanism of the turntable unit  64  is activated so as to clamp the disc  53  ( FIG. 29(   i )). Then, the locking shaft  61   b  fixed with the locking member  61   a  is released so as to make the turntable unit  64  in a mechanically floating state, the fourth stocker  81  on which the disc  53  was previously set is moved downward, and the reproduction of the selected fourth disc  53  is started ( FIG. 29(   j ). 
   When the user carelessly inserts two discs  53  successively in the insertion of the disc  53  shown in  FIG. 28(   b ), the conventional disc player  50  senses the successive insertion and tries to eject the second disc  53  by fail-safe function. However, if the user tries to push in the second disc  53  further against the ejecting operation, the first disc  53  previously inserted is pushed forward from its positioned place. In this case, the disc  53  cannot be placed on the turntable  64   a  on standby at the prescribed standby position shown in  FIG. 28(   d ), and moreover, the disc  53  falls to the stocker  81  side. 
   In the conventional disc player  50 , since the thus fallen disc  53  widely moves in the unoccupied space inside the system, the fallen disc  53  cannot be placed on the turntable  64   a  again. As a result, the disc  53  is held in a dislocated state from the stocker  81  and cannot be ejected through the disc insert/eject slot  54   a.    
   If the disc  53  is held in the dislocated state from the stocker  81 , the disc player  50  recognizes that no disc  53  is set on the stocker  81 . Therefore, when the next disc  53  is inserted, an attempt to set the disc  53  again on the stocker  81  with the disc  53  dislocated therefrom is made. As a result, two discs are stacked, so that the system gets clogged with them so as to become inoperable. 
   In the conventional disc player  50 , when vibration or shock stronger than the allowable values is applied thereto during the disc reproduction shown in  FIG. 28(   g ) or  FIG. 29(   j ), the disc  53  set on the top stocker  81  of the lower part (the fourth from the bottom in  FIG. 28(   g ), while the third from the bottom in  FIG. 29(   j )) is sometimes dislocated from the stocker  81 . 
   However, in the conventional disc player  50 , once the disc  53  is dislocated from the stocker  81 , it widely moves inside the system as it is in the dislocated state, and it is impossible to return the disc  53  to its original normal position. Therefore, the disc  53  cannot be placed on the turntable  64   a , and the disc  53  dislocated from the stocker  81  cannot be ejected through the disc insert/eject slot  54   a , similarly to the above case. 
   In the conventional disc player  50 , when strong vibration or shock is applied thereto during the dividing operation of the stockers  81  (the operation proceeding from  FIG. 29(   f ) to  FIG. 29(   g )) in changing of the disc  53  to be reproduced and the like, the locations of the division projections  81   f  in the right and left side portions of the stocker  81  in engagement with the division slide plates  57  sometimes become different from each other. As a result, the stocker  81  gets inclined and the dividing operation is interrupted, so that the system becomes inoperable. 
   When thus failing to divide the stockers  81 , the disc  53  is dislocated from the stocker  81  and falls out of the stocker  81 , so that it cannot be ejected through the disc insert/eject slot  54   a , similarly to the above cases. 
   In cases where the disc  53  cannot be taken out, or in cases where the system becomes inoperable, troublesome activities of removing the disc player  50  from the vehicle, disassembling it, taking out the disc  53  blocking inside the system, reassembling the disc player  50 , and mounting it on the vehicle, must be conducted. 
   SUMMARY OF THE INVENTION 
   The present invention was developed in order to solve the above problems, and it is an object of the present invention to provide a disc player, whereby even when an inserted disc is not normally set on a stocker, or a normally set disc is dislocated from a stocker, the disc can be reset in the normal position on the stocker during a stocker lifting/division operation, so that the normal operating condition can be quickly recovered without troublesome removing activities. 
   In order to achieve the above object, a disc player ( 1 ) according to the present invention is characterized by a disc player comprising multiple disc setting devices for stocking discs and a lifting division device to lift up and down and divide these disc setting devices, which comprises a movement control device to control the movement of a disc unexpectedly dislocated from the disc setting device. 
   Using the above disc player ( 1 ), the movement of a disc unexpectedly dislocated from the disc setting device with vibration or the like can be controlled by the movement control device. For example, through the lifting/division operation of the disc setting devices by a driving control device, the disc can be set in the normal position on the disc setting device. Therefore, even when an inserted disc is not normally set on the disc setting device, or a normally set disc is dislocated from the disc setting device, it is possible to prevent the occurrence of problems that the disc cannot be ejected from the system or that the system becomes inoperable. As a result, without troublesome removing activities, the normal operating condition can be quickly recovered. 
   A disc player ( 2 ) according to the present invention is characterized by the movement control device, comprising a first disc guide which is inserted through an insertion hole formed in the periphery of the disc setting device, being arranged in a direction almost orthogonal to the disc plane in the above disc player ( 1 ). 
   Using the above disc player ( 2 ), even when an inserted disc is not normally set on the disc setting device, or a normally set disc is dislocated from the disc setting device, it is possible to conduct the position control with the first disc guide in such a manner that the disc does not move outward from the periphery of the disc setting device, resulting in a narrow movement range of the disc. 
   A disc player ( 3 ) according to the present invention is characterized by the first disc guide, having a step portion formed in such a manner that the upper portion above a prescribed position is farther away from the central axis of a disc set on the disc setting device than the lower portion in the above disc player ( 2 ). 
   In the above disc player ( 3 ), the step portion is formed in the first disc guide. Therefore, when a disc is reproduced above the disc setting devices, it is possible to prevent the disc in reproduction and the first disc guide from coming into contact with each other. 
   A disc player ( 4 ) according to the present invention is characterized by comprising a slide chassis to horizontally move a disc carrying device on which a turntable and a pickup are mounted to a prescribed position, and the movement control device comprising a second disc guide arranged at a prescribed place on the disc setting device side of the slide chassis in any of the above disc players ( 1 )–( 3 ). 
   In the above disc player ( 4 ), the movement control device comprises the second disc guide arranged at a prescribed place on the disc setting device side of the slide chassis. Therefore, for example, even when an inserted disc is not normally set on the disc setting device, or a disc is dislocated from the disc setting device because the disc setting devices fail to be normally divided during the lifting/division operation of the disc setting devices, it is possible to control the movement of the dislocated disc toward the slide chassis side above the slide chassis. 
   Therefore, the movement of the disc outward from the second disc guide can be reliably inhibited, resulting in a narrow movement range of the disc. As a result, it becomes easy to set the dislocated disc in the normal position on its original disc setting device through the lifting/division operation. 
   A disc player ( 5 ) according to the present invention is characterized by comprising a mount chassis arranged below the slide chassis to lift up and down the slide chassis, and the movement control device comprising a third disc guide arranged at a prescribed place on the disc setting device side of the mount chassis in any of the above disc players ( 1 )–( 4 ). 
   In the above disc player ( 5 ), the movement control device comprises the third disc guide arranged at a prescribed place on the disc setting device side of the mount chassis. Therefore, for example, even when a disc is dislocated from the disc setting device because the disc setting devices fail to be normally divided during the lifting/division operation of the disc setting devices, or a disc is dislocated from the disc setting device with vibration or the like during disc reproduction, it is possible to control the movement of the dislocated disc toward the mount chassis side below the slide chassis. 
   Therefore, the movement of the disc outward from the third disc guide can be reliably inhibited, resulting in a narrow movement range of the disc. As a result, it becomes easy to set the dislocated disc in the normal position on its original disc setting device through the lifting/division operation. 
   A disc player ( 6 ) according to the present invention is characterized by the third disc guide, which is formed by upwardly bending part of the mount chassis in the above disc player ( 5 ). 
   Using the above disc player ( 6 ), since it is not necessary to mount new parts thereon, the assembling process thereof can be simplified. 
   A disc player ( 7 ) according to the present invention is characterized by the disc setting device comprising an antifalling device to prevent the falling of a disc from the disc setting device in any of the above disc players ( 1 )–( 6 ). 
   In the above disc player ( 7 ), the disc setting device comprises the antifalling device. Therefore, the falling of a disc from the disc setting device can be inhibited, so that it is possible to prevent the disc from getting caught in a state of being laid across multiple disc setting devices. Therefore, the lifting/division operation for normally setting the disc in the normal position on its original disc setting device can be normally conducted. 
   A disc player ( 8 ) according to the present invention is characterized by the antifalling device, which is formed by extending a disc receiver of the disc setting device in the direction of the center of a disc to be set on the disc setting device in the above disc player ( 7 ). 
   In the above disc player ( 8 ), the antifalling device is formed by extending a disc receiver of the disc setting device in the direction of the center of a disc to be set on the disc setting device. Therefore, for example, even when a disc is inserted in an inclined state relative to the disc setting device, or a disc is dislocated from the disc setting device with vibration or the like so as to get inclined, the falling of the disc from the disc setting device can be reliably inhibited. 
   A disc player ( 9 ) according to the present invention is characterized by a tapered portion to guide a disc in a state of dislocated from the normal position on the disc setting device to the normal position in piling the disc setting devices by lifting and division, which is formed in the periphery of the disc setting device in any of the above disc players ( 1 )–( 8 ). 
   In the above disc player ( 9 ), the tapered portion is formed in the periphery of the disc setting device. Therefore, it is possible to push in a disc in a state dislocated from the normal position on the disc setting device along the tapered portion during piling of the disc setting devices in the lifting/division operation, so that the disc can be reliably guided to the normal position. 
   A disc player ( 10 ) according to the present invention is characterized by the tapered portion, which also serves as an antifloating device for preventing a disc set on the disc setting device from floating in the above disc player ( 9 ). 
   Using the above disc player ( 10 ), since the tapered portion also serves as the antifloating device, the antifloating device can be allowed to have the two functions simply by changing the processing shape thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a sectional side view schematically showing the construction of a disc player according to an embodiment of the present invention; 
       FIG. 2  is a perspective view showing the construction of a distinctive part of the disc player according to the embodiment; 
       FIG. 3  is a perspective view schematically showing the construction of a main chassis of the disc player according to the embodiment; 
       FIG. 4  is a perspective view schematically showing the construction of a disc guide of the disc player according to the embodiment; 
       FIG. 5  is a perspective view schematically showing the construction of a mount chassis of the disc player according to the embodiment; 
       FIG. 6  is a perspective view schematically showing the construction of a floating chassis of the disc player according to the embodiment; 
       FIG. 7  is a perspective view schematically showing the construction of a slide chassis of the disc player according to the embodiment; 
       FIG. 8  is a perspective view schematically showing the construction of a disc guide of the disc player according to the embodiment; 
       FIG. 9  is a perspective view schematically showing the construction of a stocker bottom board of the disc player according to the embodiment; 
       FIGS. 10(   a )–( b ) are diagrams schematically showing the construction of a stocker of the disc player according to the embodiment, wherein  FIG. 10(   a ) is a perspective view, while  FIG. 10(   b ) is an enlarged fragmentary view showing an antifloating claw and its vicinity; 
       FIG. 11  is a perspective view schematically showing the construction of a stocker top board of the disc player according to the embodiment; 
       FIG. 12  is a sectional side view showing the operation during disc insertion in the disc player according to the embodiment; 
       FIG. 13  is a sectional side view showing the operation during disc insertion in the disc player according to the embodiment; 
       FIG. 14  is a sectional side view showing the operation during disc insertion in the disc player according to the embodiment; 
       FIG. 15  is a sectional side view showing the operation during disc insertion in the disc player according to the embodiment; 
       FIG. 16  is a sectional side view showing the operation during disc insertion in the disc player according to the embodiment; 
       FIG. 17  is a sectional side view showing the operation during disc insertion in the disc player according to the embodiment; 
       FIG. 18  is a sectional side view showing the operation during disc reproduction in the disc player according to the embodiment; 
       FIG. 19  is a sectional side view showing the operation during disc reproduction in the disc player according to the embodiment; 
       FIG. 20  is a sectional side view showing the operation during disc reproduction in the disc player according to the embodiment; 
       FIG. 21  is a sectional side view showing the operation during disc reproduction in the disc player according to the embodiment; 
       FIG. 22  is a sectional side view showing the operation during disc reproduction in the disc player according to the embodiment; 
       FIG. 23  is a sectional side view showing the operation during stocker lifting/division in the disc player according to the embodiment; 
       FIG. 24  is a sectional side view showing the operation during stocker lifting/division in the disc player according to the embodiment; 
       FIG. 25  is a sectional side view showing the operation during stocker lifting/division in the disc player according to the embodiment; 
       FIG. 26  is a sectional side view schematically showing the construction of a conventional disc player; 
       FIGS. 27(   a )–( b ) are diagrams schematically showing the construction of a stocker of the conventional disc player, wherein  FIG. 27(   a ) is a perspective view, while  FIG. 27(   b ) is an enlarged fragmentary view showing an antifloating claw and its vicinity; 
       FIGS. 28(   a )–( g ) are simplified side views showing the operation during disc insertion in the conventional disc player; and 
       FIGS. 29(   a )–( j ) are simplified side views showing the operation during disc changing and reproduction in the conventional disc player. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The preferred embodiments of the disc player according to the present invention are described below by reference to those Figures.  FIG. 1  is a sectional side view schematically showing the construction of a disc player according to an embodiment.  FIG. 2  is a diagram showing a distinctive part of the disc player shown in  FIG. 1 , which is a perspective view seen from the rear side of  FIG. 1 . Here, the same marks are affixed to component parts having the same functions as those of a conventional disc player  50  shown in  FIG. 26 . 
   The significant differences between the disc player according to the embodiment and the conventional disc player  50  are that disc guides  13 ,  20   a  and  24  are newly arranged, that the construction of a stocker  31  is modified, and that the shape of each part is altered in response to the arrangement of the disc guides  13 ,  20   a  and  24 . 
   Reference numeral  10  in the figure represents a disc player. Above the forward portion of a main chassis  12  constituting the disc player  10 , a mount chassis  20  which can be displaced up and down by engagement thereof with turntable lifting slide plates (not shown) slidably mounted on the sidewalls of the main chassis  12  is arranged. 
   On the mount chassis  20 , a disc guide  20   a  for controlling the forward movement of a disc  53  dislocated from a stocker  31  is formed. On the mount chassis  20 , a floating chassis  22  is arranged through a floating mechanism  61 . 
   On the floating chassis  22 , a slide chassis  23  is mounted in such a manner as to be slidable in a back-and-forth direction relative to the floating chassis  22 . 
   On the slide chassis  23 , disc guides  24  for controlling the forward movement of the disc  53  dislocated from the stocker  31 , and a swing board  66  with a turntable unit  64  and a PU unit  65  mounted thereon are placed. Above the swing board  66 , an insert/eject mechanism  73  is arranged. 
   At prescribed places in the rearward portion of the main chassis  12 , a couple of lifting guides  55  and a couple of disc guides  13  are vertically mounted. On the main chassis  12 , a stocker bottom board  30 , six stockers  31  for setting discs  53  thereon and a stocker top board  32  in ascending order are laminated with the lifting guides  55  inserted through insertion holes  30   c ,  31   f  and  32   c  formed therein, respectively, and the disc guides  13  inserted through insertion holes  31   g  formed in each periphery  31   a  of the stockers  31 . 
   On the sidewalls of the main chassis  12 , lifting slide plates  56  with step-like lifting grooves (not shown) formed thereon are slidably mounted along the sidewalls, so that with the movement of the lifting slide plates  56 , the stocker bottom board  30  is lifted up and down. 
   On the sidewalls of the main chassis  12 , division slide plates  57  with division grooves  57   a  formed thereon are slidably mounted along the sidewalls, so that with the movement of the division slide plates  57 , the stockers  31  and the stocker top board  32  are divided into the upper and lower parts. 
   A control circuit  40 , conducting driving control of each section, which is mounted on a substrate, is arranged on the outside wall of the main chassis  12 . 
   The distinctive portions of each component part of the disc player  10  are described below. Here, the differences from the conventional disc player  50  shown in  FIG. 26  are chiefly mentioned. 
     FIG. 3  is a perspective view schematically showing the construction of the main chassis  12 . 
   At prescribed places in the rearward portion of the main chassis  12 , a couple of mounting holes  12   a  for mounting the disc guides  13  are formed. 
     FIG. 4  is a perspective view schematically showing the construction of the disc guide  13  set in the mounting hole  12   a.    
   The disc guide  13  comprises a guide supporting portion  13   c  with a screw hole  13   a  and an extruded pin  13   b , and an almost quadrangular-prism-like guide portion  13   d  almost vertically standing on the guide supporting portion  13   c . In the guide portion  13   d , a step portion  13   e  is formed in such a manner that the upper portion above a prescribed position is farther away from the central axis of a disc  53  set on the stocker  31  than the lower portion. 
   The prescribed position in which the step portion  13   e  is formed is predetermined so as to be lower than the position of a disc  53  in reproduction. The size of the step of the step portion  13   e  is selected in consideration of the runout width of the disc  53  in reproduction and the like so that the disc  53  and the guide portion  13   d  do not come into contact with each other during reproduction. 
   At a prescribed position in the lower part of the guide portion  13   d , a convex portion  13   f  is formed so that it is located on the almost same plane as the inner wall of the periphery  31   a  of the stocker  31  in mounting. 
     FIG. 5  is a perspective view schematically showing the construction of the mount chassis  20 . 
   The mount chassis  20  comprises a recessed portion  20   b  whose rear part is concavely formed in the form of an almost semicircular arc in accordance with the disc shape, and a disc guide  20   a  formed by upwardly bending part of the mount chassis  20  located near the center of the recessed portion  20   b . The height of the disc guide  20   a  is selected to be almost the same as the floating chassis  22  arranged above the mount chassis  20  so that a disc  53  does not enter between the floating chassis  22  and the mount chassis  20 . 
   On both sidewalls of the mount chassis  20 , lifting projections  20   c  to be brought into engagement with the turntable lifting slide plates (not shown) which allow the mount chassis  20  to be displaced up and down, interlocking with the division slide plates  57 , are placed. 
     FIG. 6  is a perspective view schematically showing the construction of the floating chassis  22 . 
   In the rear portion of the floating chassis  22 , a recessed portion  22   a  is formed in the form of an almost semicircular arc in accordance with the disc shape, and in the position overlapping the disc guide  20   a  of the mount chassis  20 , a notch  22   b  to be a clearance for the disc guide  20   a  is formed. 
     FIG. 7  is a perspective view schematically showing the construction of the slide chassis  23 . 
   In the rear portion of the slide chassis  23 , a recessed portion  23   a  is formed in the form of an almost semicircular arc in accordance with the disc shape, and at prescribed places in the recessed portion  23   a  (places where no disc guides can be a hindrance to the swinging displacement of the swing board  66 ), mounting holes  23   b  for mounting disc guides  24  are formed. And arc-like guide grooves  23   c  for guiding in the swinging displacement of the swing board  66  are formed, and slide positioning projections  23   d  are fixed on both sidewalls of the forward portion. 
     FIG. 8  is a perspective view schematically showing the construction of the disc guide  24 . 
   The disc guide  24  comprises a guide supporting portion  24   c  with a screw hole  24   a  and extruded pins  24   b  formed thereon, and a guide portion  24   d  almost vertically formed along a sidewall of the guide supporting portion  24   c . In the upper part of the guide portion  24   d , a tapered plane  24   e  is formed, while in the lower part thereof, an extended portion  24   g , which is downwardly extended from the bottom  24   f  of the guide supporting portion  24   c , is formed. 
   The disc guide  24  is set in the mounting holes  23   b  with the guide portion  24   d  facing inward (to the rear side) so that the extended portion  24   g  in the lower part of the guide portion  24   d  fits on the recessed portion  23   a  of the slide chassis  23 . 
     FIG. 9  is a perspective view schematically showing the construction of the stocker bottom board  30 . 
   The stocker bottom board  30  is formed approximately in the form of a rectangle in such a manner as to be able to hold the stockers  31  almost horizontally, except for a notch  30   a  in the center portion of the forward part thereof and notches  30   b  to be a clearance in the position overlapping the disc guide  13 . Insertion holes  30   c  for inserting the lifting guides  55  therethrough, passage holes  30   d  to be a passage of a coil spring connected to the stocker top board  32 , and spring hooks  30   e  for hooking the coil springs are formed thereon. At four places on both side portions of the stocker bottom board  30 , lifting projections  30   f  for vertical displacement in engagement with step-like lifting grooves formed on the lifting slide plates  56  are fixed. 
     FIG. 10  comprises diagrams schematically showing the construction of the stocker  31 , wherein  FIG. 10(   a ) is a perspective view, while  FIG. 10(   b ) is an enlarged fragmentary view showing an antifloating claw and its vicinity. 
   The stocker  31  comprises a periphery  31   a  formed in the form of an almost semicircular arc so as to surround the outer regions of a disc  53 , and a widely formed disc receiver  31   b  having a function of supporting the outer regions of a disc  53  and a function of preventing a dislocated disc  53  from falling. 
   In the rear portion of the periphery  31   a , an antifloating claw  31   d  having a wide tapered plane  31   c  on the top thereof is formed so as to be inwardly convex from the inner wall of the periphery  31   a . On both side portions of the periphery  31   a , division projections  31   e  for division in engagement with division grooves  57   a  of the division slide plates  57 , a couple of insertion holes  31   f  for inserting the lifting guides  55  therethrough, and a couple of insertion holes  31   g  for inserting the disc guides  13  therethrough are formed. The insertion holes  31   g  are formed approximately in the form of a rectangle so that one side thereof overlaps the inner wall plane of the periphery  31   a . On both end portions of the periphery  31   a , dislocation preventive projections  31   h  for preventing the dislocation of the stockers  31  in piling are formed. 
     FIG. 11  is a perspective view schematically showing the construction of the stocker top board  32 . 
   The stocker top board  32  is formed in such a manner as to be able to retain the surface of a disc  53  set on the uppermost stocker  31 . On both side portions thereof, division projections  32   a  corresponding to the division projections  31   e  of the stocker  31 , and spring hooks  32   b  for hooking one end of the coil spring caught with the spring hook  30   f  of the stocker bottom board  30 , are formed. 
   On the stocker top board  32 , a couple of insertion holes  32   c  for inserting the lifting guides  55  therethrough, dislocation preventive holes  32   d  to be brought into engagement with the dislocation preventive projections  31   h  of the uppermost stocker  31 , notches  32   e  to be a clearance in the position overlapping the disc guide  13 , and a notch  32   f  in the center portion are formed. 
   The main operation of the disc player  10  according to the embodiment is described below. 
   The operation of the disc player  10  in cases where an inserted disc  53  is not set in the normal position on a selected stocker  31  during disc insertion operation is described below by reference to sectional side views shown in  FIGS. 12–17 . 
     FIG. 12  shows the situation wherein, in an insertion standby state where a command to set a disc  53  on the fifth stocker  31  from the bottom is given by the user, the user carelessly tries to insert two discs  53  successively, so that without being positioned by the insert/eject mechanism  73 , the first disc  53  is pushed out toward the stocker  31  side. 
   The pushed-out disc  53  falls onto the selected fifth stocker  31 . At this time, since the disc receiver  31   b  of the stocker  31  is widely formed by extending in the direction of the center of the disc, the disc  53  never falls below the fifth stocker  31  and rests on the disc receiver  31   b  of the fifth stocker  31 . 
   In this situation, it is impossible to place the disc  53  on the turntable  64   a , but after a fixed timing, the turntable unit  64  is horizontally moved toward the stocker  31  side ( FIG. 13 ). At this time, the fallen disc  53  is pushed and moved toward the stocker  31  side in a state of being mounted on the turntable  64   a . However, with the disc guide  13 , the position of the disc  53  is controlled so that it cannot move outward from the periphery  31   a  of the stocker  31 . 
   Then, the turntable unit  64  and the fifth stocker  31  are caused to ascend, and an attempt to set the disc  53  on the fifth stocker  31  is made ( FIG. 14 ). However, in this situation, since the center of the disc  53  is off its position, the disc  53  cannot be set in the normal position on the fifth stocker  31 . The disc  53  is in a state of being caught between the fifth stocker  31  and the sixth stocker  31  thereabove. 
   After finishing the removing operation of the disc  53  onto the fifth stocker  31 , the turntable unit  64  is moved to under the insert/eject mechanism  73 . The slide chassis  23  is also moved back to the position in the insertion standby state ( FIG. 15 ). 
   The upper stockers  31  and the stocker top board  32  are caused to descend ( FIG. 16 ). At this time, the front portion of the disc  53  off the fifth stocker  31  descends along the disc guide  24 , so that the movement thereof outward from the disc guide  24  is controlled. And when the disc  53  is lowered below the slide chassis  23 , the forward movement thereof is controlled with the disc guide  20   a , instead of the disc guide  24 . 
   As a result, the movement of the disc  53  is controlled with the disc guides  13 ,  20   a  and  24  so that the outer regions of the disc  53  off the fifth stocker  31  is located on the tapered plane  31   c  of the antifloating claw  31   d  formed on the stocker  31 . 
   When the stockers  31  are piled up, the disc  53  dislocated on the fifth stocker  31  is pushed onto the disc receiver  31   b  thereof along the tapered plane  31   c  so as to be set in the normal position thereon ( FIG. 17 ). After that, the operation can proceed to its normal one. 
   The operation of the disc player  10  in cases where a disc  53  is dislocated from a stocker  31  during disc reproduction is described below by reference to sectional side views shown in  FIGS. 18–22 . 
   In the disc player  10 , a disc  53  set on the top stocker  31  of the divided lower part (the fourth from the bottom in  FIG. 18 ) is held with a pressing piece (not shown) arranged near the center of the disc and the antifloating claw  31   d  so as not to be off the stocker  31 . However, when vibration or shock stronger than the allowable values is applied thereto, the disc  53  sometimes gets off the stocker  31 .  FIG. 18  shows the situation. 
   In the situation of  FIG. 18 , the position of the fourth dislocated disc  53  is controlled with the disc guide  13  so that it cannot move outward from the periphery  31   a  of the stocker  31 . Moreover, the movement thereof is controlled with the disc guide  20   a  so that the dislocated disc  53  cannot enter between the mount chassis  20  and the floating chassis  22 . 
   When a command to change the reproduced disc is given by the user in this situation, in order to set the now-reproducing disc  53  onto the fifth stocker  31 , the turntable unit  64  and the fifth stocker  31  are caused to ascend so as to be piled with the upper stocker  31 . The catching mechanism of the turntable unit  64  is released and the disc  53  is set on the disc receiver  31   b  of the fifth stocker  31  ( FIG. 19 ). 
   After finishing the removing operation of the disc  53  onto the fifth stocker  31 , the turntable unit  64  is moved to under the insert/eject mechanism  73 . The slide chassis  23  is also moved back to the position in the insertion standby state ( FIG. 20 ). 
   After that, the stockers  31  piled up in the upper part are lowered so as to be overlaid on the stockers  31  in the lower part ( FIG. 21 ). In this piling, the movement of the disc  53  is controlled with the disc guides  13  and  24  so that the outer regions of the disc  53  on the fourth stocker  31  is located on the tapered plane  31   c  of the antifloating claw  31   d  of the stocker  31 . 
   By lowering all the stockers  31  and piling up them, the disc  53  dislocated on the fourth stocker  31  is pushed onto the disc receiver  31   b  thereof along the tapered plane  31   c  so as to be set in the normal position thereon ( FIG. 22 ). 
   And then, the operation can normally proceed to the division/lifting operation of the stockers  31  for reproducing the selected disc  53 . 
   The operation of the disc player  10  in cases where a disc  53  is dislocated from a stocker  31  because the division operation of the stockers  31  is not normally conducted during the division/lifting operation of the stockers  31  is described below by reference to  FIGS. 23–25 . 
   In the disc player  10 , when strong vibration or shock is applied thereto during the division/lifting of the stockers  31  in ejecting or changing a disc  53 , the engagement states of the division projections  31   e  of the stocker  31  with the division slide plates  32  on the left and right sides sometimes become different from each other, so that the stocker  31  gets inclined and the disc  53  gets off the stocker  31 .  FIG. 23  shows the situation. 
     FIG. 23  shows the situation wherein a disc  53  of the fifth stocker  31  from the bottom is selected for reproduction, and in the middle of lifting/division of the fifth stocker  31 , strong vibration is applied, resulting in abnormal division. 
   In this situation, the disc  53  on the inclined fifth stocker  31  cannot be held in a horizontal position, so that it gets off the stocker  31  and moves within the system. However, the position of the dislocated disc  53  is controlled with the disc guide  13  so that the disc  53  cannot move outward from the periphery  31   a  of the stocker  31 , and is controlled with the disc guide  24  so that it cannot move outward from the slide chassis  23 . 
   Since it is possible neither to move the turntable unit  64  nor to continue the division of the stockers  31  in this situation, the division slide plates  57  are moved so as to clear the division state, and the stockers  31  in the upper part (the fifth and sixth from the bottom) are caused to descend to be overlaid on the stockers  31  in the lower part ( FIG. 24 ). 
   In this piling, with the disc guides  13  and  24 , the movement of the disc  53  is controlled so that the outer regions of the disc  53  on the fifth stocker  31  is located on the tapered plane  31   c  of the antiflaoting claw  31   d  of the stocker  31 . 
   Then, by descending and piling up all the stockers  31 , the disc  53  dislocated on the fifth stocker  31  is pushed onto the disc receiver  31   b  thereof along the tapered plane  31   c  to be set in the normal position thereon ( FIG. 25 ). 
   And then, the division/lifting operation of the stockers  31  can be normally conducted. 
   Using the above disc player  10  according to the embodiment, even in cases where an inserted disc  53  is not normally set on a stocker  31 , in cases where a normally set disc  53  is dislocated from a stocker  31 , or the like, the disc guide  13  enables the position control in a manner whereby the disc  53  cannot move outward from the periphery  31   a  of the stocker  31 . 
   The disc guide  24  arranged at a prescribed place on the stocker  31  side of the slide chassis  23  enables the control of the movement of the disc  53  toward the slide chassis  23  side above the slide chassis  23 . 
   And the disc guide  20   a  arranged at a prescribed place on the stocker  31  side of the mount chassis  20  enables the control of the movement of the disc  53  toward the mount chassis  20  side below the slide chassis  23 . 
   Therefore, the movement of the disc  53  outward from the circumference surrounded by the disc guides  13 ,  24  and  20   a  can be reliably inhibited. By conducting the lifting/division operation with narrowing the movement range of the disc  53  unexpectedly dislocated from the stocker  31  because of vibration or the like, it becomes possible to set the dislocated disc  53  in the normal position on the stocker  31 . The occurrence of a problem that the disc  53  cannot be ejected or that the system becomes inoperable can be prevented, so that it is possible to quickly recover the normal operating state. 
   Since the step portion  13   e  is formed in the disc guide  13 , it is possible to prevent the disc  53  in reproduction and the disc guide  13  from coming into contact with each other when the disc  53  is reproduced above the stockers  31 . 
   Since the stocker  31  has the disc receiver  31   b  formed by extending in the direction of the center of the disc  53  set on the stocker  31 , which also functions as an antifalling device, the falling of the disc  53  from the stocker  31  can be inhibited, so that it is possible to prevent the disc  53  from being caught in a state of being laid across multiple stockers  31 . For example, even in cases where a disc  53  is inserted in a state of inclined relative to the stocker  31 , or in cases where a disc  53  is dislocated from the stocker  31  because of vibration or the like so as to get inclined, the falling of the disc  53  from the stocker  31  can be reliably prevented. As a result, the lifting/division operation for setting the disc  53  in the normal position on the stocker  31  can be normally conducted. 
   Since the tapered plane  31   c  is formed in the periphery  31   a  of the stocker  31 , the disc  53  in a dislocated state from the normal position on the stocker  31  can be pushed in along the tapered plane  31   c  in piling the stockers  31  during the lifting/division operation, so that the disc  53  can be surely guided to the normal position. 
   Since the tapered plane  31   c  also serves as the antifloating claw  31   d , the antifloating claw  31   c  can be allowed to have the two functions simply by changing the processing shape thereof. 
   Here, in the above embodiment, the disc guide  13  is mounted on the main chassis  12 . However, in another embodiment, the disc guide  13  can be mounted on the stocker bottom board  30 . 
   Moreover, in the above embodiment, four disc guides, comprising the disc guides  13  and  24 , are mounted, but the mounting of at least three disc guides in the vicinity of the outer regions of the set disc may be sufficient to obtain almost the same effects, if it is possible to arrange guides in such a manner that every central angle between adjacent guides is more than 90 degrees. Thus, the mounting number or positions of disc guides may be selected as necessary in consideration of operation spacing between the disc guides and other component parts inside the system, or the like.