Abstract:
An optical disc mounting mechanism, comprising, a front sweeper ( 32 ) for catching an optical disc from a front slot ( 12 ) and bringing said disc into a drive module followed by pushing an optical disc out of the front slot; a rear sweeper ( 34 ) for pushing the disc out of a rear slot ( 16 ) or catching the disc from the rear slot; one or more front sensors for sensing the insertion of an optical disc; a center sensor for sensing the present of the disc in a drive module; one or more rear sensors for sensing the moving direction of the disc; a drive head for reading or writing the disc; a controlling mechanism for mounting or unmounting an optical disc to said drive head ( 92 ). The said disc mounting mechanism has good adaptability and simple structures.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a field of optical drive for data storage or retrieval, more specifically, to a disc mounting mechanism. 
     BACKGROUND OF THE INVENTION 
     Multimedia programs are often stored on media, such as compact disc (CD), for running in a computer or other apparatus with a drive. Typically, the disc can be loaded into a drive and read by a reader inside the drive through a tray. The tray is triggered when a disc is sufficiently inserted and it moves backwards and forwards to eject and retract the disc. Usually there are internal mechanisms to control the movement of the tray, such as those disclosed in the U.S. Pat. No. 6,256,278 and US patent application 20060026611A1. However, all the related art references work in the same way: the user must locate the target disc and insert it into the drive. Then the drive can read and for write onto the disc or run the program. If the user has a large number of discs, it will be time consuming and bothersome to pick up the target disc and run it. Alternate approaches include the application of roller technology into the drive mechanism. However, rubber rollers which grasp the disc will be easily worn out and as such are inappropriate for applications beyond occasional consumer use. 
     There were also many technical solutions in the related art to handle this problem. US patent application 2005/0024996A1 provides circular support platters to hold discs and an external pick device with arm to efficiently pick the target disc from a large number of discs. U.S. Pat. No. 7,254,818 also provides a self aligning disc tray drive in which robot arm is used to pick a disc from a stack to move it into a tray assembly. The reference also discloses the use of a disc tray which also has a finished disc storage bin. 
     In all of the above applications, however, the disclosed mechanisms do not have good adaptability and have complex structures which can be more prone to mechanical failure over time. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide an unconventional way of disc insertion and retrieval process to save space and to have a higher device reliability while reducing the number of parts needed. 
     The presently claimed invention is a disc mounting mechanism comprising both front and rear slots for disc inserting. The mechanism has a front sweeper and a rear sweeper under the control of gears to catch and push the disc. The mechanism also has front sensors to detect the insert of the disc in the front slot, center sensor to detect the presence of the disc inside the drive module and rear sensors to detect the moving direction of the disc in the rear slot. The mechanism also has two drive plates holding a drive head and a magnet device for reading and writing the disc. The drive plates are controlled by two knobs. The movement of these knobs will further cause the movement of a disc drain which is used for the disc mounting and unmounting. 
     The advantage of the front and rear sensors is to ensure the position of the disc and enable firmware to accurate signals to the disc operation. The advantage of the disc drain is to align the disc to the right position between the drive head and the magnet device. During the mounting process, the disc will not be disturbed by human intervention and will assure the accuracy. The components of the mechanism above cooperate with each other to obtain a fluent and accurate result of disc mounting and overcome the disadvantages of the conventional drive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of the disc mounting mechanism; 
         FIG. 2  is the front view of the front and rear sweeper mechanism; 
         FIG. 3  is the left side view of the disc mounting mechanism without the right side cover  14 ; 
         FIG. 4  is an exploded view of the disc knob, disc shaft, disc lever and disc drain; 
         FIG. 5  is the top view of the disc knob, disc shaft, limit switches and disc lever. 
         FIG. 6  is the flow chart of disc insert from front process steps. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIG. 1 , the disc mounting mechanism  10  of the present invention as claimed is a box with two slots: the front slot  12  is on the right side cover  14  and the rear slot  16  on the left side cover  18 . Inside the right side cover  14 , front sensors  20  are arranged on the opposite sides of the front slot  12 . The front sensors in one embodiment are infra-red sensors but could be any type of sensors which are able to detect the presence or absence of a disk. A slot  26  is arranged on the inner board  22  in consistent with the front slot  12 . The right side cover  14  and the inner board  22  are attached to the mechanism  10  in the direction of arrow  101  and  102 . The left side cover  18  is attached to the mechanism  10  in the direction of arrow  103 . A supporting frame  28  is vertically arranged on the bottom  30 . A front sweeper  32  and a rear sweeper  34  are separately arranged on the supporting frame  28 . 
     In  FIG. 2 , the front sweeper  32  pivots on the shaft  36  and the rear sweeper  34  pivots on the shaft  38 . The front sweeper  32  is a whole piece of sheet metal in a desired embodiment composed of a catch  32 ( a ), an arm  32 ( b ), a plate  32 ( c ), two knobs  32 ( d   1 ) and  32 ( d   2 ) and disc stop arm  32 ( e ). The catch  32 ( a ) is a thin straight strip which is vertical to the supporting frame  28 . When the front sweeper  32  is in its lowest position, the catch  32 ( a ) is located in a narrow groove  40 . The arm  32 ( b ) has a curve shape and is connected to the end of the catch  32 ( a ). The other end of the arm  32 ( b ) is connected to a plate  32 ( c ). The knobs  32 ( d   1 ) and  32 ( d   2 ) are separate sector-like projections on the plate  32 ( c ). The plate  32 ( c ) is connected to a half gear  42  with rivets (not shown). The half gear  42  is able to pivot on the shaft  36 . As the relationship between the front sweeper  32  and the half gear  42  is fixed by the rivets, the rotation of the half gear  42  will cause synchronization rotation of the front sweeper  32  in the direction of arrow  108 . Another thin strip called disc stop arm  32 ( e ) is connected to the plate  32 ( c ). 
     Continuing with  FIG. 2 , there are two micro switches  46  and  48  arranged on a PCB of the supporting frame  28  near the knobs  32 ( d   1 ) and  32 ( d   2 ). With the rotation of the front sweeper  32 , the switches  46  and  48  can be switched by the knobs  32 ( d   1 ) and  32 ( d   2 ). The working processes will be discussed in detail below. 
     The rear sweeper  34  in a preferred embodiment is also a whole piece of sheet metal composed of a catch  34 ( a ), an arm  34 ( b ), a plate  34 ( c ) and two knobs  34 ( d   1 ) and  34 ( d   2 ). The arrangement of the rear sweeper  34  is similar to that of the first sweeper  32 . The catch  34 ( a ) is a thin straight strip which is vertical to the supporting frame  28 . When the rear sweeper  34  is in its lowest position, the catch  34 ( a ) is located in a narrow groove  50 . The arm  34 ( b ) has a curve shape and is connected to the end of the catch  34 ( a ). The other end of the arm  34 ( b ) is connected to a plate  34 ( c ). The knobs  34 ( d   1 ) and  34 ( d   2 ) are separate sector like projections on the plate  34 ( c ). The plate  34 ( c ) is connected to a half gear  52  with rivets (not shown). The half gear  52  is able to pivot on the shaft  38 . As the relationship between the rear sweeper  34  and the half gear  52  is fixed by the rivets, the rotation of the half gear  52  will cause synchronization rotation of the front sweeper  34  in the direction of arrow  110 . 
     There are two micro switches  56  and  58  arranged on the PCB of the supporting frame  28  near the knobs  34 ( d   1 ) and  34 ( d   2 ). With the rotation of the rear sweeper  32 , the switches  56  and  58  can be switched by the knobs  34 ( d   1 ) and  34 ( d   2 ). The working processes will be discussed in detail below. 
     Micro switches  46  and  48  control the first motor (not shown) through a control circuit  60 . The first motor is used to control the rotation and rotation direction of the axis of shaft  62 . In a similar way, the micro switches  56  and  58  control the second motor (not shown) through the control circuit  60 . The second motor is also used to control the rotation and rotation direction of the shaft  64 . Each shaft of shafts  62  and  64  has a set of gears working together to finally control the movement of the front sweeper  32  and rear sweeper  34  through the half gears  42  and  52 . 
     Returning to the  FIG. 1 , a first drive plate  70  is attached to the mechanism  10  in the direction of arrow  103 ( a ) and is used for covering the supporting frame and the front and rear sweepers thereon. The first drive plate  70  is arranged between the inner board  22  and the left side cover  18  through a rod  79 . A magnet device  78  is arranged on the inner side of the first drive plate  70  facing the sweepers. On the top of the first drive plate  70  attaches a connecter  80 . The second drive plate  90  is at the back of the mechanism  10  and is attached between the inner board  22  and the left side cover  18  through another rod (not shown). There is a drive head  92  for reading and writing arranged on the second drive plate  90 . Furthermore, there are a pair of rear sensors  210  and a center sensor  212  arranged on the upper portion of the mounting mechanism  10  between the drive plates  70  and  90 . 
     Referring to the  FIG. 3 , the other end of the disc stop arm  32 ( e ) mentioned above is connected to a disc stopper  44 . The disc stopper  44  is able to move along the lower portion of the slot  26  in the direction of arrows  106 . The rod  79  for the first drive plate  70  is arranged inside a hole  77  at the left bottom of the inner board  22 . The rod  83  for the second drive plate  90  is arranged inside another hole  79  at the right bottom of the inner board  22 . The first and second drive plates  70  and  90  are able to separately pivot on the rods  79  and  83  in the direction of  105  and  107 . There is drive stopper  89  of a “L” shape attached to the second drive plate  90 . The drive stopper  89  extends out of the inner board  22  through a slot  91 . With the movement of second drive plate  90  along the arrow  107 , the drive stopper  89  is able to block the slot  26 . Optionally, the second drive plate  90  can have another drive stopper. The other drive stopper which has similar structure of drive stopper  89  is arranged facing the left side cover  18  for blocking the rear slot  16 . 
     Referring to the  FIG. 4 , there is a disc drain  94  for keeping the disc aligned between the first and the second drive plates (not shown). The disc drain  94  is a groove. Close to the front sweeper  32 , the disc drain  94  is attached with a vertical drain lever  96  through an axis  98 . The vertical drain lever  96  will move in the direction of arrow  116  under the control of the horizontal drain lever  200 . The horizontal drain lever  200  is connected to the vertical drain lever  96  through an axis  202 . 
     Referring to  FIG. 5 , two drive knobs  224  and  226  are arranged opposite each other on the top of the mechanism  10 . These two knobs  224  and  226  concentrically go through a drive shaft  228  and can move closely or separately in the direction of arrow  118  under the rotation of the drive shaft  228 . Connector  80  of the front drive plate  70  is arranged close to the drive knob  224  and connector  86 , which is attached to and can be simultaneously moved with the second drive plate  90 , is arranged close to the drive knob  226 . There are two switches  220  and  222  and a control circuit  218  arranged on the top of the mechanism  10  close to one drive knob  224 . The switches  220  and  222  control the third motor (not shown) through the control circuit  218 . The third motor is used to control the rotation of the drive shaft  228 . The working processes will be discussed in detail below. 
     Retuning back to  FIG. 4 , when the knob  224  is approaching the knob  226 , the wedged edge  224 ( a ) of the knob  224  will be under the horizontal lever  200  and the said lever  200  will be raised in the direction of arrow  120 . The raise of horizontal lever  200  will cause the drop of vertical lever  96  under the pivot of the axis  202 . The disc drain  94  will thus be lowered by the horizontal lever  96 . 
     The working procedure of the whole mechanism is as follow: 
     Drive Module Initialization 
     The purpose of this initialization process is to ensure that the drive module is always ready to use when the unit is powered up. During this process, all the discs are pushed back to the storage device and there is no disc in the drive module. 
     The initialization process starts 3 seconds after each time the power is on. The drive plates are checked first to assure they are opened. Later, the front sweeper is checked. The front sweeper  32  will be lowered if it is not at the lowest position. Next, the rear sweeper  34  is managed for two steps: raise the rear sweeper and then lower it. 
     After finishing the initialization process, the mechanism of this invention is ready for reading and writing. As the disc can be inserted both from the front slot  12  and the rear slot  16 , the processes for inserting will be described separately. 
     Disc Insertion from Front 
     The purpose of this process is to insert a disc through the front slot  12  to read/write in the disc module. 
     Referring to the  FIG. 6 , in step  601 , insert a disc into the front slot. When the disc is passing through the two sets of front sensors, in step  602 , the front sensors can detect the presence of the disc. The front sensors are two sets of infra-red sensors. As mentioned above, the two sets of sensors are placed perpendicular to the disc. One of each set provides a constant infra-red beam and the other one works as the receiver. When the disc exists in front of the sensor, the infra-red beam is broken. 
     The first motor is used to control the rotation of the axis and through a series of gears to control the rotation of front sweeper. In step  603 , after two sets of sensors detect the presence of the disc, the front sweeper raises until the knobs touches the switch to stop the rotation of the first motor and it can catch the disc which was inserted into the front slot. Incidentally, the disc stop arm of the front sweeper which is attaching to the drive stopper will be lowered to allow insertion of the disc into the drive module. The reason for arranging two sets of front sensors is to avoid misread signals. The disc has a round edge. If there is only one set of sensors, when the disc is rolling, it may break the constant beam and reactivate the front sensors again. Therefore, a misread signal is presented resulting wrong movements of the first sweeper. The front sensor will regard the rolling of the disc as an insert of new disc. The disc will be pushed back into the storage device (not shown). The whole mechanism is waiting for the next disc. Two sets of front sensors will be helpful to avoid such circumstance. 
     Then in step  604 , the center sensor notices the present of the disc. The center sensor is made up of one set of infra-red sensor with one of it working as a sender of infra-red beam and the other working as a receiver. Due to the position of the center sensor, it is hard to misread the information. When the infra-red beam is broken, it usually means that one disc is present within the scope of the drive module. In step  605 , the front sweeper is then lowered to place the media in the center of the drive module. At the same time, the drive stopper is raised to close the front slot. This is to ensure that when a disc is within the drive module, no other disc can be inserted into the drive module from the front. 
     In step  606 , the rear sweeper rises to push the disc through the rear slot. The angle of the rear sweeper can be about 110° to ensure that the disc will be pushed out of the rear slot completely. Then in step  607 , as the rear sensors are two sets of infra-red sensors, they are able to detect the moving direction of the disc. The switches and are used to stop the movement of the rear sweeper by knobs through the rotation of plate. In step  608 , the clearance of both rear sensors indicates that the disc has already been moved from the disc module. The rear sweeper will be lowered to wait for the next instruction. 
     Disc Insertion from Rear 
     Disc insertion at the rear slot does not require the raise of the rear sweeper at the beginning as the inserted disc is completed in a “non-human intervention” condition. After the media is inserted into the rear slot, the rear sensors  210  will detect an opposite direction of the movement of the disc and then determine that the media is coming in from the rear. The disc rolls into the drive module and the center sensor detects the presence of the disc. The front sweeper then rises and pushes the disc out to the front slot. The angle of the raised front sweeper is about 45°, which is enough for the disc to protrude from the front slot  12 . The disc is able to sit on the front slot  12  and can be picked by the user. The front slot sensor detects the presence of the disc at the front slot. After the disc is picked, the front slot sensor clears and then the front sweeper will be lowered. The disc will be waiting at the front slot for duration of 10 seconds. After that, if the disc hasn&#39;t been picked by the user, the front sensor will detect the presence of the disc again. The disc will then be retracted back into the storage device following the Disc Insertion from Front procedures. 
     Disc Mounting and Unmounting 
     If the disc needs reading or writing, then the next stage before the disc is pushed out from either the rear slot  16  or the front slot  12  will be mounting the disc to the drive. The center sensor  212  will be used to assure the existence of the disc as the center sensor  212  is located at the top portion of the mechanism. The center sensor  212  can only sense the signal when the disc is in the center. Firmware of the mechanism will provide a reading or writing signal to the third motor (not shown) to rotate the shaft  228 . The shaft  228  will make the drive knob  226  and  224  moving toward each other in the direction of arrow  118 . As mentioned before, the first drive plate  70  is attached to the drive knob  224  through the connector  80  and the second drive plate  90  is attached to the drive knob  226  through the connector  86 . When these knobs  226  and  224  are close enough, the wedged edge  224 ( a ) of the knob  224  will raise the horizontal drain lever  200  to cause further movement of the vertical lever  96 . At last the disc drain is lowered to ensure the disc to be operated between the magnet device  78  and the drive head  92  in the right position. The lower of the disc allows the disc to spin freely when the disc is being operated. The rotation of the shaft  228  is controlled by the limited switches  222  and  220  through the movement of the knob  224 . When the disc is operated between the magnet device  78  and the drive head  92 , the first drive plate  70  and the second drive plate  90  are parallel. 
     When the disc is mounted between the first and second drive plates  70  and  90 , the “L” shape drive stopper  89  will be moved together with the second drive plate  90  within the slot  91  to block the slot  26 . The “L” shape drive stopper  89  is used to protect the disc while the drive head is operating on the disc and to prevent any damage to the disc and any interruption to the operation process. Optionally, another drive stopper will also be moved together with the second drive plate  90  to block the rear slot  16 . Thus no further disc can be inserted into the slots  26  and  16  when the disc is read or written. 
     The unmounting process is similar to the mounting process. The difference only lies on the opposite moving direction of the knobs  224  and  226 . The plates  70  and  90  are separated. As the plates  70  and  90  separately pivot on the rods  79  and  83 , during the unmounting process, the side view of drive plates  70  and  90  present a shape of concave. The disc drain  94  is raised to move the disc out of the drive head  92  and the magnet device  78 . 
     It will be appreciated that while only a few specific embodiments of the invention have been described herein for the purposes of illustration, various changes or modifications may be made without departing from the scope and spirit of the invention.