COMPACT DISK CHANGER

Abstract: Compact disk changer comprises a body, a tray having a rotational shaft for horizontally extracting from or retracting into said body, and a rotational circular plate table or roulette, on which an odd number of more than three compact disks are horizontally placed in a same plane, and arranged rotatably on the tray around the rotational shaft of the tray, wherein a revolutional shaft of the roulette is offset against a rotational shaft of the roulette.

Description: COMPACT DISK CHANGER TECHNICAL FIELD This invention relates to a compact disk changer, more particularly a compact disk changer for moving a center of a rotational circular plate table or roulette toward a relatively wide-spaced side area to reduce an overall rotational diameter, when a portion of a compact disk resting portion that is formed on an edge of the roulette on which a plurality of compact disks are placed is positioned on an edge of compact disk changer body. BACKGROUND ART Generally, a compact disk (hereafter referred to as a "CD") changer is a device that contains a plurality of CDs. A rotational circular plate table or roulette for placing a plurality of CDs is installed at the CD changer, and an optic pick-up device reproduces data stored on the CD placed at the roulette. The roulette is of rotary-type, and the CD placed on the CD resting portion moves to the optic pick-up device by rotation of the roulette. A conventional CD changer having the above rotary-type roulette, as shown in FIGs . 1 and 2, comprises a body frame 110, a plate-shaped tray 120 moving slidably in/out of the body frame 110, a rotational circular plate table or roulette 130 installed rotatably on the tray 120 and on which a plurality of CDs are placed, a rotating member (which is illustrated later) installed on the tray 120 for rotating the roulette 130, and a drive unit 140 mounted with an optic pick-up device (not shown) for reproducing data stored on the CD placed on the roulette 130. Three CD resting portions 138 are formed on the roulette 130 installed on the tray 120, and are extended radially from a rotational shaft 130C of the roulette 130. The roulette 130 rotates around the rotational shaft 130C of the roulette 130, so that the CD resting portion 138 of the roulette 130 on which the CD is placed is positioned above the drive unit 140. The rotating member comprises a driving motor 132 mounted on the tray 120, a connecting gear 134 rotated by the driving motor 132, and a circular gear 136 installed fixedly below the rotational shaft 130C of the roulette 130 to mesh with the connecting gear 134 to rotate, thereby rotating the roulette 130. By the above structure, the roulette 130 is rotated by driving of the driving motor 132 so that the CD resting portion 138 on which the CD is placed is positioned above the drive unit 140. At this time, the drive unit 140 is raised by driving of the motor (not shown) to chuck the CD against a bracket 140B, and thereafter reproducing data stored on the CD. However, the roulette 130 rotates in an inner space of a body frame 110 to move the CD to the drive unit 140. The inner space of the body frame 110 has a size for containing geometric circle in which an edge of the CD which is placed on the CD resting portion 138 rotates within the inner space of the body frame 110. Therefore, the body frame 110 has a predetermined size which limits the production of smaller size CD changers. DISCLOSURE OF INVENTION Therefore, the present invention has been proposed to overcome the above described problems in the prior art, and accordingly it is an object of the present invention to provide a CD changer for moving a center of a roulette toward a relatively wide-spaced side area to reduce an overall rotational diameter, when a CD resting portion, formed on an edge of the roulette on which a plurality of CDs are placed, is positioned on an edge of the CD changer body. To achieve the above objects, the present invention provides a compact disk changer which is comprised of a body, a tray having a rotational shaft for horizontally extracting from or retracting into the body, a rotational circular plate table or roulette, on which an odd number of more than three compact disks are horizontally placed in a same plane, and arranged rotatably on the tray, and a mechanism for revolving the plate table around the rotational shaft of the tray during rotation of the plate table around a rotational center of the plate table. Further, the mechanism comprises a plurality of protrusion members formed radially from the rotational shaft of the tray, a restriction member for restricting movement of the roulette during rotation of the rotational shaft, and a revolutional/rotational member for revolving the roulette around the rotational shaft of the tray as well as rotating the roulette around the rotational shaft of the roulette by movement of the protrusion member. Furthermore, the protrusion member is a vortex of a first equilateral triangle, the restriction member is comprised of a groove formed on the tray, and pins numbering more than two which are extended downwardly from the lower surface of the roulette and are distanced equally, for sliding movement along the groove, and the revolutional/rotational member is a number of sides of a second equilateral triangular cutout hole which is point- contacted with the vortex of the first equilateral triangle, in which each side of the second equilateral triangular cutout hole is longer than that of the first equilateral triangle. Further, a diameter of a circular plate formed on the first equilateral triangle is longer than that of an inscribed circle of the second equilateral triangular cutout hole. Furthermore, the first equilateral triangle is comprised of a pair of equilateral triangles which are rotated independently, and a helical torsion spring for forcing the vortex of each of the equilateral triangles in counter directions. Alternatively, the compact disk changer is comprised of a body, a tray having a rotational shaft for horizontally extracting from or retracting into the body, and a rotational circular plate table or roulette, on which an odd number of more than three compact disks are horizontally placed in a same plane, and arranged rotatably on the tray around the rotational shaft of the tray, wherein a revolutional shaft of the roulette is offset against a rotational shaft of the roulette. BRIEF DESCRIPTION OF THE DRAWINGS This invention will be better understood and its various objects and advantages will be more fully appreciated from the following description taken in conjunction with the accompanying drawings, in which: FIG. 1 is a perspective view of a conventional CD changer, FIG. 2 is a plane view of FIG. 1 excepi for an upper bracket, FIG. 3 is an exposed perspective view of a roulette rotational structure of a first embodiment of the CD changer in accordance with the present invention, FIG. 4 is a side cross sectional view of an assembled roulette rotational structure of a first embodiment of the CD changer in accordance with the present invention, FIG. 5 is a plane view of the CD changer showing a state when the roulette is positioned at position A, FIG. 6 is a plane view of the roulette rotational structure showing a state of FIG. 5, FIG. 7 is a plane view of the CD changer showing a state when the roulette is positioned at position B, FIG. 8 is a plane view of the roulette rotational structure showing a state of FIG. 7, FIG. 9 is an exposed perspective view of a roulette rotational structure of a second embodiment of the CD changer in accordance with the present invention, FIG. 10 is a side cross sectional view of an assembled roulette rotational structure of a second embodiment of the CD changer in accordance with the present invention, FIG. 11 is a plane view of the CD changer showing a state when the roulette is positioned at position A of FIG. 5, and FIG. 12 is a plane view of the CD changer showing a state when the roulette is positioned at position B of FIG. 7. BEST MODE FOR CARRYING OUT OF THE INVENTION Hereinafter, a first embodiment of this invention will be described in detail with reference to Figures 3-8. A CD changer in accordance with the present invention comprises a roulette 70 having a plurality of CD resting portions 72 on which each CD is placed, a plate-shaped tray 10 which is extracted from or retracted horizontally into a body of the CD changer and on which the roulette 70 is rotationally placed, and a drive unit 80 mounted with an optic pick-up device for reproducing data stored on the CD placed on the roulette 70. Further, the CD changer is comprised of a driving motor 20 mounted on the tray 10, a central circular plate 30 rotated by the driving motor 20, a first equilateral triangle 32 formed under the central circular plate 30, and an offset circular plate 40 emcompassing the central circular plate 30 and formed under the roulette 70. Furthermore, a section in the form of a second equilateral triangle is cut-out from the offset circular plate 40, in which each vortex of the first equilateral triangle 32 is contacted on sides of the second equilateral triangular cut-out hole 42 in the circular plate 40, pins 76 numbering three which are extended downwardly from the lower surface of the roulette 70 and are distanced equally in an equilateral triangle shape, and a groove curve 12 is formed on the tray 10 for sliding movement of pins 76. A motor pulley 22 is provided under the driving motor 20, and a revolution pulley 34 is provided under the central circular plate 30. Both pulleys 22,34 are coupled by a belt 24. The size of both pulleys 22,34 is determined dependant to the low speed of the central plate 30 with respect to the high speed of the motor 20. The second equilateral triangular cut-out hole 42 in the circular plate 40 is larger than the first equilateral triangle 32, that is, each side of the second equilateral triangular cut-out hole 42 in the circular plate 40 is longer than that of the first equilateral triangle 32. Thus, a gap is generated between each vortex of the first equilateral triangle 32 and each side of the second equilateral triangular cut-out hole 42 in the circular plate 40. A diameter (not shown) of a circular plate 30 formed on the first equilateral triangle 32 is longer than that of an inscribed circle (not shown) of the second equilateral triangular cut-out hole 42 in the circular plate 40, thus preventing the circular plate 30 from slipping through the second equilateral triangular cut-out hole 42 in the circular plate 40. The groove curve 12 is formed approximately as a square of which each side of the square is bowed inwardly. The roulette 70 rotates around the center rotational shaft of the offset circular plate 40 attached on the lower surface of the roulette 70, and pins 76 extended downwardly from the portion distanced from circumference of the offset circular plate 40 are inserted by freely sliding into the groove curve 12, thus enabling the roulette 70 to revolve around a revolutional shaft 34C. Hereinbelow, the operation and the effect of the CD changer of the first embodiment in accordance with the present invention is described in detail. When a user places a plurality of CDs on the CD resting portion 72 of the roulette 70 and pushes the tray 10, the tray 10 slides into the body frame and is ready to reproduce data stored on the CD. At this time, the CD resting portion 72 on which CD is placed is positioned above the drive unit 80, and the drive unit 80 is raised so that the optic pick-up device mounted on the drive unit 80 reproduces data stored on the CD. After the optic pick-up device reproduced the data stored on the CD, the drive unit 80 is lowered. And, as shown in FIGs. 5 and 7, the roulette 70 rotates from point A to point B to transfer an other CD to the reproducing position . Mechanism for rotating the roulette 70 is as follows. When the driving motor 20 rotates, the driving force is transmitted to the central circular plate 30 formed integrally to the revolutional pulley 34 by the belt 24. As shown in FIGs. 3-6, the central circular plate 30 rotates in the offset circular plate 40. One of any vortexes of the first equilateral triangle 32 formed under the central plate 30 contacts with any one side of the second equilateral triangular cut-out hole 42 in the circular plate 40, thus rotating the second equilateral triangular cut-out hole 42 in the circular plate 40. The rotation of the second equilateral triangular cutout hole 42 of the offset circular plate 40 causes the roulette 70 as well. Since the pins 76 move along the groove curve 12 formed on the tray 10, the roulette 70 revolves eccentrically against the revolutional shaft 34C. While the roulette 70 revolves around the revolutional shaft 34C and the offset circular plate 40 formed under the roulette 70 rotates around the rotational shaft 40S, simultaneously, the CD resting portion 72 on which the selected CD is placed is moved to the area above the drive unit 80. Next, the drive unit 80 rises to chuck the selected CD and to reproduce the data srored on the CD. As described above, the roulette 70 rotates around the rotational shaft 40S of the offset circular plate 40 and revolves around the revolutional shaft 34C along the groove curve 12. As shown in FIGs. 7 and 8, when any one of the CD resting portions 72 approaches the edge of the tray 10, the rotational center of the roulette 70, i.e., the rotational shaft 40S of the offset circular plate 40, moves toward the opposite portion against the revolutional shaft 34C. That is, when the roulette 70 rotates to move from point A to point B, the CD resting portion 72 of the roulette 70, positioned at the closest position from the center of a roulette 70, moves to the inner wall of the edge of the body frame, and the center of the roulette 70 moves to a relatively wide-spaced side against the inner wall of the edge of the body frame, so that an overall rotational diameter is reduced. Accordingly, the roulette 70 rotates freely without contacting the inner wall of the body frame in the relatively small space which the roulette 70 forms. Therefore, the CD changer can be produced in a smaller size than the conventional sizes. A second embodiment of this invention will be described in detail with reference to Figures 5, 7, 9-12. The CD changer according to the invention is similar to that of the first embodiment shown in Figures 3-8, except for the structure of the moving elements which are a gist of the invention. Thus an explanation with the numbers being referenced to the same elements will be made. No detailed description will be made of the components which are common to the first embodiment. The CD changer is further comprised of a driving motor 20 mounted on the tray 10, a central circular plate 30 rotated by the driving motor 20, a first upper equilateral triangle 32U and a first lower triangle 32L which are assembled with the rotational shaft 34R at the lower area of the central circular plate 30 and are elastically pushed in counter directions by a helical torsion spring 44, and an offset circular plate 40 emcompassing the central circular plate 30 and formed under the roulette 70. Furthermore, a section in the form of a second equilateral triangle is cut out from the offset circular plate 40, in which each vortex of both equilateral triangles 32U,32L is contacted on sides of the second equilateral triangular cut-out hole 42 in the circular plate 40, pins 76 numbering three are extended downwardly from the lower surface of the roulette 70 and are distanced equally in an equilateral triangular shape, and a groove curve 12 is formed on the tray 10 for sliding movement of pins 76. The body of the helical torsion spring 44 is assembled at the revolutional shaft 34C of the revolutional pulley 34, and each end of the helical torsion spring 44 is coupled with each protrusion 41,47 which is respectively extended from first upper and lower equilateral triangles 32U,32L. A pin 36 is provided on the upper surface of the revolutional pulley 34. Slots 42,48 are formed at each upper and lower equilateral triangles 32U,32L, through which pin 36 is inserted. Thus, each of the first upper and lower equilateral triangles 32U,32L is pushed in counter directions by the helical torsion spring 44. Each vortex of the first upper and lower equilateral triangles 32U,32L is contacted to the side of the second equilateral triangular cutout hole 42 formed in the offset circular plate 40. The movement range of the first upper and lower equilateral triangles 32U,32L is restricted by the pin 36 inserted into the slots 42,48. The second equilateral triangular cut-out hole 42 in the circular plate 40 is larger than the first upper and lower equilateral triangles 32U,32L, that is, each side of the second equilateral triangular cut-out hole 42 in the circular plate 40 is longer than that of the first upper and lower equilateral triangles 32U,32L. A diameter (not shown) of a circular plate 30 formed above the first upper and lower equilateral triangles 32U,32L is longer than that of an inscribed circle (not shown) of the second equilateral triangular cut-out hole 42 in the circular plate 40, thus preventing the circular plate 30 from slipping through the second equilateral triangular cut-out hole 42 in the circular plate 40. The groove curve 12 is formed approximately as a square of which each side of the square is bowed inwardly. The roulette 70 rotates around the center shaft of the offset circular plate 40 attached on the lower surface of the roulette 70, and pins 76 extended downwardly from the portion distanced from a circumference of the offset circular plate 40 are inserted by freely sliding into the groove curve 12, thus enabling the roulette 70 to revolve around a rotational shaft 34C. Hereinbelow, the operation and the effect of the CD changer of the second embodiment in accordance with the present invention is described in detail. When a user places a plurality of CDs on the CD resting portion 72 of the roulette 70 and pushes the tray 10, the tray 10 slides into the body frame and is ready to reproduce data stored on the CD. At this time, the CD resting portion 72 on which CD is placed is positioned above the drive unit 80, and the drive unit 80 is raised so that the optic pick-up device mounted on the drive unit 80 reproduces data stored on the CD. After the optic pick-up device reproduces the data srored on the CD, the drive unit 80 is lowered. And, as shown in FIGs. 5 and 9-11, the roulette 70 rotates from point A to point B to transfer an other CD to the reproducing position. Mechanism for rotating the roulette 70 is as follows. When the driving motor 20 rotates, the driving force is transmitted to the central circular plate 30 formed integrally to the revolutional pulley 34 by the belt 24. As shown in FIGs. 9-12, the central circular plate 30 rotates in the offset circular plate 40. One of any vortexes of the first upper and lower equilateral triangles 32U,32L formed under the central plate 30 contacts with any one side of the second equilateral triangular cut-out hole 42 in the circular plate 40 in counter direction. The second equilateral triangular cutout hole 42 in the circular plate 40 is rotated by a push of one vortex of the first equilateral triangle, which is rotated in the same direction as the rotational direction of the revolutional shaft 34C, among the first upper and lower equilateral triangles 32U,32L. Like the above description, the helical torsion spring 44 elastically arranged in the first upper and lower equilateral triangles 32U,32L forces each first upper and lower equilateral triangle 32U,32L in counter directions. Therefore, the offset circular plate 40 and the roulette 70 having the offset circular plate 40 attached under the roulette 70 move tightly in the second equilateral triangular cut-out hole 42 in the circular plate 40. The rotation of the second equilateral triangular cutout hole 42 of the offset circular plate 40 causes the rotation of the roulette 70 as well. Since the pins 76 move along the groove curve 12 formed on the tray 10, the roulette 70 revolves eccentrically against the revolutional shaft 34C. While the roulette 70 revolves around the revolutional shaft 34C and the offset circular plate 40 formed under the roulette 70 rotates around the rotational shaft 40S, simultaneously, the CD resting portion on which the selected CD is placed is moved to the area above the drive unit 80. Next, the drive unit 80 is raised to chuck the selected CD and reproduce the data srored on the CD. Hereafter, since the rotation and the revolution of the roulette 70 is the same as the first embodiment, the detailed explanation is omitted for the purpose of avoiding the repetition. While this invention has been particularly shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be effected therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims: CLAIMS : 1. Compact disk changer comprising: a body; a tray having a rotational shaft for horizontally extracting from or retracting into said body; a rotational circular plate table, on which an odd number of more than three compact disks are horizontally placed in a same plane, and arranged rotatably on said tray; and a revolving means for revolving said plate table around said rotational shaft of said tray during rotation of said plate table around a rotational center of said plate table. 2. The compact disk changer according to claim 1, wherein said revolving means comprises a plurality of protrusion members formed radially from said rotational shaft of said tray, a restriction member for restricting movement of said roulette during rotation of said rotational shaft, and a revolutional/rotational member for revolving said roulette around said rotational shaft of said tray as well as rotating said roulette around said rotational shaft of said roulette by movement of said protrusion member. 3. The compact disk changer according to claim 2, wherein said protrusion member is a vortex of a first equilateral triangle, said restriction member is comprised of a groove formed on said tray, and pins numbering more than two which are extended downwardly from the lower surface of said roulette and are distanced equally, for sliding movement along said groove, and said revolutional/rotational member is an offset cicular plate that remain after a second equilateral triangular section is cutout from said circular plate resulting in a hole which is point-contacted with said vortex of said first equilateral triangle, in which each side of said second equilateral triangular cutout hole is longer than that of said first equilateral triangle. 4. The compact disk changer according to claim 2, wherein a diameter of a circular plate formed on said first equilateral triangle is longer than that of an inscribed circle of said second equilateral trianglular cutout hole. 5. The compact disk changer according to claim 3, wherein said first equilateral triangle is comprised of a pair of equilateral triangles which are rotated independently, and a helical torsion spring for forcing said vortex of each of said equilateral triangles in counter directions. 6. Compact disk changer comprising: a body; a tray having a rotational shaft for horizontally extracting from or retracting into said body; and a rotational circular plate table, on which an odd number of more than three compact disks are horizontally placed in a same plane, and arranged rotatably on said tray around said rotational shaft of said tray, wherein a revolutional shaft of said plate table is offset against a rotational shaft of said plate table.

Inventors: KIM HAG-RYEOL, KIM, HAG-RYEOL
Applicants: DAEWOO ELECTRONICS CO LTD, DAEWOO ELECTRONICS CO., LTD.
Application year: 1998
Main classification: G11B17
IPC codes: G11B17