Disk changer

Abstract: The invention is intended to reduce the size of a disk changer. The disk changer comprises a first rack member (23) supporting on its one end side a latch pawl (32) adapted to latch a pin (17), and a second rack member (24) supporting on its other end side a latch pawl (33) adapted to latch the pin (17), the first and second rack members being slidably supported in parallel with each other. After the first rack member (23) transfers a tray (6) by a predetermined distance, latching of the tray (6) thereon is switched over from the first rack member (23) to the second rack member (24). The tray (6) is then further transferred by the second rack member (24).

Description: The present invention relates to a disk changer to be used in combination with a magazine accommodating a plurality of disks, such as compact disks (CD's), for withdrawing a desired disk out of the magazine for playback. Disk changers of the type for withdrawing a desired one of a plurality of trays accommodated in a magazine are known. A conventional disk changer of this type has a tray withdrawing mechanism having a structure in which one end of a swing arm engages with a tray to withdraw the tray out of the magazine. However, the tray withdrawing mechanism having a swing arm as described above suffers from the problem that the swing arm moves over a wide range and thus space sufficient to ensure the wide range of movement of the swing arm is required, making it difficult to reduce the disk changer size. An object of the present invention is to solve the above-mentioned problem of the prior art, and to provide a disk changer which has a reduced size. To achieve the above object, according to the present invention, there is provided a disk changer comprising a housing in which a magazine containing at least one disk is inserted via an insertion opening thereof said disk changer including a disk conveying mechanism for drawing a disk out of the magazine and conveying it to a turntable, said disk conveying mechanism including drive means for moving a driven member which conveys said disk in a drawing direction from a disk storage position to a disk turntable position or in a direction opposite to the drawing direction, characterized in that said disk changer also comprises first and second rack members supported to be slidable in said drawing direction or in said direction opposite to the drawing direction, and extending in said drawing direction, said first and second rack members each being arranged with one end near to said disk turntable position, said first rack member having at its said one end a first latch member for latching said driven member, said second rack member having at its said another end a second latch member for latching said driven member, and latching switchover means for actuating said first and second latch members to latch or unlatch said driven member, said first and second rack members are juxtaposed with each other prior to drawing a disk out of said magazine, and said first latch member is switched over by said latching switchover means to latch said driven member so that said drive means engages only with said first rack member to thereby move it towards said disk turntable position, and, when said first rack member reaches a predetermined position, said latching switchover means unlatches said driven member from said first latch member and switches over said second latch member to cause it to latch said driven member to permit said drive means to engage only with said second rack member to move it towards said disk turntable position, where it is once again juxtaposed with said first rack member. With the arrangement of the present invention, when the drive source is actuated with the driven member, such as a tray holding a compact disk (CD) thereon, latched to one of the rack members by its associated latch member, the one of the rack members is moved by a driving force of the drive source so that the driven member is also moved therewith. When the one of the rack members has moved to a predetermined position, the rack member latching the driven member thereon is released and the other rack member is latched to the driven member, and then the driven member is further moved with the other rack member. In this way, the driven member is transferred by a predetermined distance with the successive movement of the first and second rack members. The foregoing and further features of the invention will be more readily understood from the following description of a preferred embodiment with reference to the drawings of which:- Fig. 1 is a perspective view of a disk changer according to the present invention; Fig. 2 is a perspective view of a magazine for use in the embodiment of figure 1; Fig. 3 is a perspective view showing a state where a tray is withdrawn from the magazine; Fig. 4 is a perspective view of a tray withdrawing mechanism; Fig. 5 is a top plan view of a tray withdrawing mechanism; Fig. 6 is an exploded perspective view of the tray withdrawing mechanism; Fig. 7 is a side view, partly in section, of the tray withdrawing mechanism; Fig. 8 is a view for explaining the operation of the tray withdrawing mechanism; Fig. 9 is another view for explaining the operation of the tray withdrawing mechanism; and Fig. 10 is yet another view for explaining the operation of the tray withdrawing mechanism. Fig. 1 shows a disk changer for compact disks (CD's) according to the embodiment of the present invention. In Fig. 1, designated by the reference numeral 1 is a box-shaped housing which has a magazine insertion opening formed on a left side of its front surface 2. Reference numeral 3 designates a slide cover supported on the front surface 2 of the housing 1 in a slidable manner, able to slide to the left and right for opening and closing the magazine insertion opening. Fig. 1 shows a state where the slide cover 3 is slid to the left side of the front surface 2 to close the magazine insertion opening. Figs. 2 and 3 show a magazine accommodating a plurality of CD's therein. In these drawings, designated by the reference numeral 4 is a box-shaped magazine body and 5 is an opening formed on one lateral side of the magazine body 4. On the inner wall surfaces of the magazine body 4, a plurality of guide pieces 7 are formed in parallel for guiding respective trays 6. A recess 8 is formed on the upper surface of each tray 6 for accommodating a CD therein and has a hole 9 at the center thereof. Reference numeral 10 designates a hook lug formed on a front edge of the tray 6. A pawl of a tray withdrawing mechanism engages with the hook lug 10 for withdrawing the tray 6 out of the magazine body 4 or returning the tray 6 back into the magazine body 4. Reference numeral 11 is a cut-out formed in the magazine body 4. In the disk changer of Fig. 1, the slide cover 3 is slid to the right to open the magazine insertion opening, and the magazine shown in Fig. 2 is inserted into the magazine insertion opening. The magazine shown in Fig. 2 is received on the left side of the housing 1 as shown in Fig. 1, while the housing 1 accommodates in the right side thereof a tray withdrawing mechanism capable of moving up and down, a turntable for drivingly rotating the CD, a clamping mechanism for clamping the CD on the turntable, an optical pickup for reading data recorded on the CD, and so forth. Fig. 4 shows an elevating plate 12 supported to be vertically movable in the housing 1 in the direction of arrow Y. In fig. 4, designated by the reference numeral 13 is a motor mounted on the elevating plate 12, 14 is a gear train for transmitting a torque of the motor 13, and 15 is a guide member fixed to the upper surface of the elevating plate 12 for supporting a pair of rack plates (not shown in fig. 4) in a slidable manner. Reference numeral 16 is a guide hole formed in the guide member 15 to guide movement of a pin 17 there-along. Reference numeral 18 is a slide member capable of sliding on the upper surface of the guide member 15. The pin 17 is inserted through a hole in the slide member 18 so that the slide member 18 is driven by the pin 17. Reference numeral 19 is a pawl capable of engaging with the hook lug 10 of a particular tray within the magazine. In a state shown in Fig. 4, the pawl 19 of the slide member 18 engages with the hook lug 10 of the tray 6 selected from among the plurality of trays in the magazine. When the motor 13 is rotated, the driving torque is transmitted through the gear train 14 to the rack plates in the guide member 15 for driving the pin 17 to move along the guide hole 16 in the direction of arrow X. Therefore, the slide member 18 is driven by the pin 17 to move together therewith, causing the tray 6 in the magazine to be withdrawn in the direction of arrow X. The CD on the withdrawn tray is clamped over the turntable by a. clamping mechanism (not shown). It is to be noted that Fig. 4 shows an outline only of the tray withdrawing mechanism for withdrawing a tray out of the magazine and returning it back into the magazine. The tray withdrawing mechanism of this embodiment will be next described with reference to Figs. 5 and 7. Reference numerals 20, 21 are respectively first and second guide pieces jointly constituting the guide member 15. These guide pieces 20, 21 are fixed to the upper surface of the elevating plate 12 by screws 22. The guide hole is formed between the first guide piece 20 and the second guide piece 21. Reference numerals 23, 24 are respectively first and second rack plates capable of sliding in the direction of arrow X (Fig. 4) while being guided by two guide grooves 25, 26 (see Fig. 7) formed in the guide pieces 20, 21. Reference numerals 27, 28 are elongate holes respectively formed in the rack plates 23, 24 for receiving the pin 17. Reference numerals 29, 30 are toothed portions respectively formed on one side of each rack plate 23, 24. These toothed portions 29, 30 are both able to mesh with a gear 31 at a final stage of the gear train 14 rotatably supported on the elevating plate 12. Reference numeral 32 is a latch pawl rotatably supported to one end (the left end in Fig. 6) of the rack plate 23 on its upper surface, and 33 is a latch pawl rotatably supported on one end (the right end in Fig. 6) of the rack plate 24 on its lower surface. The latch pawls 32, 33 are respectively turned while being guided by guide surfaces 34, 35 (see Fig. 7) formed on the guide pieces 20, 21, in such a manner as to latch or release the pin 17. The aforesaid slide member 18 is provided with the pawl 19 which is able to engage with the hook lug 10 of the tray 6. In Fig. 5, reference numerals 36, 37 are lock pieces rotatably supported on the upper surface of the elevating plate 12 by shafts 38, 39 and reference numerals 40, 41 are springs for normally biasing the lock pieces 36, 37, respectively. The lock pieces 36, 37 are engaged with cutouts 42, 43 of the rack plates 23, 24 for slightly locking the rack plates 23, 24, respectively. Upon rotation of the gear 31, the tray transferring mechanism slides the slide member 18 between the left and right ends of the guide hole 16, shown in Fig. 5. This sliding movement allows the tray 6 engaging with the pawl 19 of the slide member to go into or come out of the magazine. Operation of the tray withdrawing mechanism will now be described with reference to Figs. 8 to 10. It is to be noted that while the rack plates 23, 24 are arranged one above the other as shown in Fig. 7, they are shown as not overlapping with each other in Figs. 8 to 10 for convenience of illustration. Fig. 8 shows a state where the slide member 18 is positioned close to the magazine as in Fig. 5. In this state, the latch pawl 32 of the first rack plate 23 is turned counterclockwise by the guide surface 34 with the pin 17 held between the latch pawl 32 and the left end of the elongate hole 27. Therefore, when the gear 31 is rotated counterclockwise, the first rack plate 23 held in mesh with the gear 31 slides to the right. Correspondingly, the pin 17 also moves to the right together with the rack plate 23. Because the pin 17 is inserted through a hole in the slide member 18, the rightward movement of the pin 17 causes the slide member 18 to move to the right, whereby the tray engaging with the pawl 19 of the slide member 18 is withdrawn out of the magazine. At this time, since the second rack plate 24 is not held in mesh with the gear 31, the second rack plate 24 will not move to the right and remains stationary regardless of the rightward movement of the first rack plate 23. When the first rack plate 23 is further moved to the right, as shown in Fig. 9, the latch pawl 32 supported on the first rack plate 23 strikes against a projection 34a of the guide surface 34 so that the latch pawl 32 is turned clockwise to be disengaged from the pin 17. Also, at the time the first rack plate 23 comes to the position shown in Fig. 9, the gear 31 does not mesh with the first rack plate 23 any longer and driving of the first rack plate 23 by the gear 31 is completed. Reference numeral 29a denotes a non-toothed portion of the first rack plate 23. While the first rack plate 23 moves from the position shown in Fig. 8 to the position shown in Fig. 9, the pin 17 is moved to the right in the elongate hole 28 of the second rack plate 24 remaining at rest and then strikes against an inner wall of the elongate hole 28 at the right end, so that the second rack plate 24 is moved to the right by the pin 17 and comes into mesh with the gear 31. Simultaneously, the latch pawl 33 supported by the second rack plate 24 is turned clockwise by the guide surface 35. Therefore, the pin 17 is now held between the latch pawl 33 and an inner wall of the elongate hole 28 at the right end. Thus, the counterpart meshing with the gear 31 is switched over from the first rack plate 23 to the second rack plate 24 and the counterpart engaging with the pin 17 is also switched over from the first rack plate 23 to the second rack plate 24. Subsequent to the state shown in Fig. 9, the second rack plate 24 is slid to the right by the torque of the gear 31 for further rightward movement of the pin 17. When the second rack plate 24 reaches the position shown in Fig. 10, the slide member 18 actuates a switch (not shown) so that the motor stops its rotation and the second rack plate 24 also stops its movement. In this way, the pin 17 is moved from the left end of the guide hole 16 shown in Fig. 8 to the right end thereof shown in Fig. 10, and the tray 6 is withdrawn out of the magazine by the slide member 18 engaging with the pin 17. The operation of returning the tray 6 back into the magazine in a reversal of the above operation of withdrawing the tray. Thus, by rotating the gear 31 clockwise, the tray returning operation proceeds in the order of sequence of Fig. 10, Fig. 9 and Fig. 8. The tray withdrawing mechanism of the illustrated embodiment, as mentioned above, employs the two rack plates 23, 24 in the form of a flat plate as primary parts. Thus, the tray withdrawing mechanism can be reduced in thickness. Also, since the tray 6 can be moved through a large distance by a combination of respective sliding movements of the two rack plates 23, 34 within a specific limited range, the tray withdrawing mechanism can be reduced in width to provide a small-sized disk changer. It should be understood that while the above embodiment is explained in connection with the mechanism for withdrawing a tray, the present invention can also be applied to a disk withdrawing mechanism for disk changers of the type where disks are directly accommodated in a magazine without using trays.

Claims: A disk changer comprising a housing (1) in which a magazine (4) containing at least one disk is inserted via an insertion opening thereof, said disk changer including a disk conveying mechanism for drawing a disk out of the magazine (4) and conveying it to a turntable, said disk conveying mechanism including drive means (31) for moving a driven member (18) which conveys said disk in a drawing direction from a disk storage position to a disk turntable position or in a direction opposite to the drawing direction, characterized in that said disk changer also comprises first and second rack members (23, 24) supported to be slidable in said drawing direction or in said direction opposite to the drawing direction, and extending in said drawing direction, said first and second rack members (23, 24) each having one end near to said disk turntable position and another end remote from said disk turntable position, said first rack member (23) having at its said another end a first latch member (32) for latching said driven member (18), said second rack member (24) having at its said one end a second latch member (33) for latching said driven member (18), and latching switchover means (34, 34a, 35, 35a) for actuating said first and second latch members (32, 33) to latch or unlatch said driven member (18), said first and second rack members (23, 24) are juxtaposed with each other prior to drawing a disk out of said magazine (4), and said first latch member (32) is switched over by said latching switchover means (34) to latch said driven member (18) so that said drive means (31) engages only with said first rack member (23) to thereby move it towards said disk turntable position, and, when said first rack member (23) reaches a predetermined position, said latching switchover means (34a, 35) unlatches said driven member (18) from said first latch member (32) and switches over said second latch member (33) to cause it to latch said driven member (18) to permit said drive means (31) to engage only with said second rack member (24) to move it towards said disk turntable position, where it is once again juxtaposed with said first rack member (23). A disk changer according to claim 1, characterised in that said latch members (32, 33) for latching said driven member (18) each comprise a latch pawl (32, 33) rotatably supported adjacent an end of an elongate hole (27, 28) formed in the respective rack member (23, 24). A disk changer according to claim 2, characterised in that said latching switchover means (34, 34a, 35, 35a) comprises guide surfaces (34, 35) coming into contact with said latch pawls (32, 33).

Inventors: DAIGAKU HAJIME, KAGOHASHI YASUYOSHI, NAKAGAWA YOSHIAKI, NAKAMA SEIJI, NAKAYAMA TUKASA, SEKIYA SHINJI, SUZUKI TAKASHI, DAIGAKU, HAJIME, KAGOHASHI, YASUYOSHI, NAKAGAWA, YOSHIAKI, NAKAMA, SEIJI, NAKAYAMA, TUKASA, SEKIYA, SHINJI, SUZUKI, TAKASHI
Applicants: MATSUSHITA ELECTRIC IND CO LTD, MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
Application year: 1992
Main classification: G11B17
IPC codes: G11B17, G11B33