1. Field of the Invention
The present invention relates to a disk recording/reproducing device provided with a tray for carrying a disk.
2. Related Art
In case a disk such as a DVD is to be recorded with data, or in case the recorded data are to be reproduced, a disk recording/reproducing device is employed such that the disk is placed on a turntable and is rotated at a high speed. A tracking control is made so that an information-reading beam may follow the information track on the disk, and a focusing control is made so that a beam spot may be precisely formed on the information track. Thus, the information is recorded and reproduced without fail.
When the disk is to be placed on the turntable, there is often employed a tray of the type, in which an opening swing door disposed in the front panel of a cabinet is slid to be opened and dosed. The disk is placed on the tray slid to protrude from the swing door and moved backward to be placed on the turntable.
A drive pinion to be rotated by a motor meshes with a rack of the tray so that the tray may be able to slide along a guide rail disposed in the disk device. When the disk is to be set or removed, the tray is pushed out into an open state, and the disk set on the tray is accommodated in the disk device as the tray moves backward. When the disk is to be reproduced, a traverse unit rises to push up the disk placed on the tray, and a spindle motor rotates at a high speed while clamping the disk on the turntable.
The conventional tray 1 slides back and forth, as the pinion rotationally driven by a reversible motor meshes with the rack 4. When the forward movement ends, the switch is turned OFF to stop the forward movement of the tray 1. When the tray 1 in a disk exchanging position, i.e., in the open state is slightly pushed by an operator's hand, the switch is turned ON so that the motor is activated backward rotation, contrary to the forward movement, to start the backward movement. This backward movement of the tray can also be started by operating a button not by the manual push.
At the end of the backward movement, the switch is turned OFF to stop the rotation of the motor. The switch for turning ON/OFF the motor is a three-point switch. This switch is adapted to be activated when its switching arm is pushed by protrusions disposed at a predetermined interval on a rack loader, which moves in the right and left direction as a cam rod boss loosely fitted in the cam groove 5 moves along the cam groove 5. The switch OFF state, in which the tray 1 protrudes to the disk exchanging position, is kept as it is when once turned OFF, due to the straight shape of the rear end of the cam groove 5. In the absence of the retaining pawl 6, the tray 1 can be extracted from the opening of the device.
When the tray loaded in the disk recording/reproducing device is pulled from the protruding state to the disk exchanging position, the retaining pawl is caught by the stopper but may be brought out or damaged if it is subjected to an excessive load. This is the problem to be solved by the invention, and the invention has an object to provide a disk recording/reproducing device, which is controlled to block the extraction of a tray by means of a motor for driving the tray forward and backward.
According to the invention, therefore, there is provided a disk recording/reproducing device with a tray, including: a tray for placing a disk thereon to carry in/out the disk; a reversible motor for driving the tray; a pinion connected to the reversible motor rotatably forward and backward; a rack loader made slidable perpendicularly to the carrying direction of the tray; and a switch for turning ON/OFF in response to the sliding action of said rack loader, wherein said rack loader having a cam rod boss rising therefrom, said tray being provided on its bottom face with a rack extending in its carrying direction and meshing with the pinion and with a generally L-shaped cam groove for fitting said cam rod boss loosely therein, said cam groove having a longitudinal cam groove extending in parallel with the rack, a transverse cam groove perpendicular to the rack, a corner cam groove formed obliquely between the longitudinal cam groove and the transverse cam groove, a trapezoidal curve portion formed near the back end of the longitudinal cam groove and curved generally in a trapezoidal shape, and a straight portion formed behind said trapezoidal curve portion and lying on an extension line of the longitudinal cam groove, and a central portion of the trapezoidal curve portion and the corner cam groove portion at passing time of the cam rod boss providing OFF area of the switch whereas the longitudinal cam groove and the straight portion providing ON area of the switch.
On the back of the trapezoidal curve portion of the cam groove, there is further formed a straight portion, which falls on the extension line of the longitudinal cam groove. When the tray in the disk exchanging position is pulled until the cam rod boss comes to the straight portion as ON area of the switch, the motor is restarted to bring back the tray to the initial position of the center of the trapezoidal curve portion.
The switch may include a switch arm arranged near the rack loader and extending toward the rack loader, and the rack loader may be provided with switching ribs at a predetermined interval, so that the switching ribs bring down the switch arm to right and left direction, as the rack loader moves, whereby the switch ON is established when the switch arm is in an upright state whereas the switch OFF is established when the switch arm falls down to the right and left direction.
Thus, according to the disk recording/reproducing device of the invention, the straight portion is further formed on the extension line of the longitudinal cam groove on the back of the trapezoidal curve portion of the cam groove, so that switch ON area is provided at the position where the cam rod boss is at the straight portion. As a result, even if the tray in the disk exchanging position is further pulled forward, when the cam rod boss comes to the straight portion, the motor can be started to move back the tray to the initial disk exchanging position. In other words, the tray is not pulled out of the front panel, and the retaining pawl or the stopper is not damaged by an excessive load.
The pinion 7 is rotationally driven by a reversible motor 9. When the pinion 7 is rotated forward and backward, the rack 4 and the tray 1 are moved forward to protrude to the disk exchanging position or are carried into the device to retract to the reproducing position. The tray 1 is moved forward and backward within a predetermined distance between the disk exchanging position and the reproducing position so that the cam rod boss 8 accordingly slides in the cam groove 5 from the front end side to the back end side. As shown in
The cam rod boss 8 is protruded from a rack loader 13 disposed on the lower side of the tray 1 to be able to freely move transversely. In accordance with the transverse movement of the cam rod boss 8 in the cam groove 5, therefore, the rack loader 13 moves transversely. To the body chassis, there is attached a switch 18 for driving the reversible motor 9 rotationally. This switch 18 is provided with a switch arm 19 extending toward the rack loader 13. As shown in
In the trapezoidal curve portion 14 of the cam groove 5, a central portion 15 provides an OFF area of the switch 18, which corresponds to the state of the switch arm 19 of the switch 18 as shown in
When the cam rod boss 8 comes from the longitudinal cam groove 10 to the trapezoidal curve portion 14, the rack loader 13 moves leftward in
As shown in
Number | Date | Country | Kind |
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2004-158969 | May 2004 | JP | national |