Slim-type optical disc drive

A slim-type optical disc drive includes a casing and a tray. A first circuit board is disposed within the casing. A second circuit board is disposed on the tray. A spring switch is disposed on the second circuit board. A first end of the spring switch is fixed on the second circuit board. A resistor is connected between the first end of the spring switch and a first power source. A second end of the spring switch is extended outside the second circuit board. In a tray-out status, the second end of the spring switch is not contacted with any object, so that a first status signal is generated. In a tray-in status, the second end of the spring switch is contacted with a conducting zone of a second power source, so that a second status signal is generated.

This application claims the benefit of People's Republic of China Application Serial No. 201210016473.1, filed Jan. 18, 2012, the subject matter of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a component of an optical disc drive, and more particularly to a switch structure of a slim-type optical disc drive.

BACKGROUND OF THE INVENTION

FIG. 1is a schematic view illustrating the inner portion of a conventional slim-type optical disc drive. As shown inFIG. 1, the slim-type optical disc drive comprises a tray110, a casing112, and two sliding rails140,142. After the tray110is pushed into casing112of the optical disc drive, the tray110is fixed within the casing112by a locking unit (not shown). Under this circumstance, the tray110is in a tray-in status. Whereas, after an eject button on the tray110is pressed by the user, the locking unit will release the tray110and the tray110will be withdrawn from the optical disc drive. Under this circumstance, the tray110is in a tray-out status. In other words, if the tray110is not stored within the casing112and the optical disc drive is in the tray-out status, the tray110may be pulled out along the rails140and142. After the tray110is pulled out, the optical disc loaded into the tray110may be replaced or the tray110may be pushed into the casing112(i.e. in the tray-in status).

Moreover, a daughter board (not shown) is fixed within the tray110. A main board160is fixed on the casing112. The main board160and the daughter board are electrically connected with each other to transmit signals through a U-shaped flexible cable150. In other words, during the process of moving the tray110, the daughter board is still in communication with the main board160.

Generally, a spindle motor120, a spindle motor driver chip (not shown), an optical pickup head130and an optical pickup head control chip (not shown) are mounted on the daughter board. In addition, a variety of circuits are installed on the main board160. These circuits include for example an analog signal microprocessor, a digital signal process (DSP)/decoder microprocessor, a flash ROM chip, a SDRAM chip, and so on. The main board160and the daughter board are in communication with each other through the U-shaped flexible cable150. Moreover, since the casing112is made of a metallic material, the casing112is also electrically connected to a ground voltage (Gnd).

After the optical disc drive confirms that the tray110is in the tray-in status, the optical disc drive is enabled. Whereas, after the optical disc drive confirms that the optical disc drive is disabled (spindle motor120and optical pickup head130are disabled), the tray110may be controlled to be in the tray-out status. Moreover, the optical disc drive is usually equipped with a limit switch162to detect the whether the tray110is in the tray-out status or the tray-in status.

Please refer toFIG. 1again. The limit switch162is mounted on the main board160. When the tray110is fixed within the casing112by the locking unit, the limit switch162is also pressed by the tray110. Consequently, the limit switch162generates a first status signal. According to the first status signal, the circuits on the main board160may confirm that the tray110is in the tray-in status, and thus the optical disc drive will be enabled. Whereas, when the tray110is in the tray-out state, the limit switch162is no longer pressed by the tray110. Consequently, the limit switch162generates a second status signal. Until the limit switch162is pressed by the tray110again and the first status signal is generated, the optical disc drive will be enabled again.

FIG. 2Ais a schematic circuit diagram illustrating a first type of conventional limit switch.FIG. 2Bis a schematic circuit diagram illustrating a second type of conventional limit switch. As shown inFIG. 2A, in a case that a touch terminal A of the limit switch162is not pressed, the second status signal at a high voltage level (Vcc) is outputted from an output terminal Out of the limit switch162. Whereas, in a case that the touch terminal A of the limit switch162is pressed, the first status signal at a low voltage level (Gnd) is outputted from the output terminal Out of the limit switch162.

As shown inFIG. 2B, in a case that a touch terminal A of the limit switch162is not pressed, the second status signal at the low voltage level (Gnd) is outputted from an output terminal Out of the limit switch162. Whereas, in a case that the touch terminal A of the limit switch162is pressed, the first status signal at the high voltage level (Vcc) is outputted from the output terminal Out of the limit switch162.

From the above discussions, the limit switch162is an important component of the optical disc drive for detecting whether the optical disc drive is in the tray-out status or the tray-in status. However, since the limit switch162is not cost-effective, it is necessary to provide another component to replace the limit switch162.

SUMMARY OF THE INVENTION

A first embodiment of the present invention provides a slim-type optical disc drive. The slim-type optical disc drive includes a casing and a tray. A first circuit board is disposed within the casing. The tray is selectively accommodated within the casing or withdrawn from the casing. A second circuit board is disposed on the tray. A spring switch is disposed on the second circuit board. A first end of the spring switch is fixed on the second circuit board. A resistor is connected between the first end of the spring switch and a first power source. The first end of the spring switch is served as an output terminal of the spring switch. A second end of the spring switch is extended outside the second circuit board. In a tray-out status, the second end of the spring switch is not contacted with any object, so that a first status signal is generated from the output terminal of the spring switch. In a tray-in status, the second end of the spring switch is contacted with a conducting zone of a second power source, so that a second status signal is generated from the output terminal of the spring switch.

A second embodiment of the present invention provides a slim-type optical disc drive. The slim-type optical disc drive includes a casing and a tray. A first circuit board is disposed within the casing. A spring switch is disposed on the first circuit board. A first end of the spring switch is fixed on the first circuit board. A resistor is connected between the first end of the spring switch and a first power source. The first end of the spring switch is served as an output terminal of the spring switch. A second end of the spring switch is extended outside the first circuit board. The tray is selectively accommodated within the casing or withdrawn from the casing, wherein a second circuit board is disposed on the tray. In a tray-out status, the second end of the spring switch is not contacted with any object, so that a first status signal is generated from the output terminal of the spring switch. In a tray-in status, the second end of the spring switch is contacted with a conducting zone of a second power source, so that a second status signal is generated from the output terminal of the spring switch.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides a slim-type optical disc drive. In comparison with the conventional optical disc drive, the relationship between the main board and the daughter board of the optical disc drive of the present invention is distinguished. The configurations of the other components (e.g. the tray110, the eject button114, the sliding rails140,142, and the casing112) are similar to those of the conventional optical disc drive, and are not redundantly described herein. Moreover, for clarification and brevity, only the daughter board of the tray110is shown but the spindle motor and the optical pickup head are not shown in the drawings.

In accordance with a key feature of the present invention, a cost-effective spring switch is employed to replace the function of the limit switch of the conventional optical disc drive in order to detect the operating status of the tray.

FIGS. 3A and 3Bschematically illustrate a circuit for detecting the operating status of the tray of the optical disc drive according to a first embodiment of the present invention. A spring switch S1is disposed on the daughter board318. A first end of the spring switch S1is fixed on the daughter board318. A resistor R is connected between the first end of the spring switch S1and a source voltage Vcc. In addition, the first end of the spring switch S1is also served as the output terminal Out of the spring switch S1. A second end of the spring switch S1is suspended and extended outside the daughter board318. As shown inFIG. 3A, in a case that the tray110is in the tray-out status, the second end of the spring switch S1is not contacted with any object. Meanwhile, a first status signal (e.g. a high voltage level) is outputted from the output terminal Out of the spring switch S1.

Whereas, as shown inFIG. 3B, in a case that the tray is in the tray-in status, the second end of the spring switch S1is contacted with an inner surface of the casing112. Since the casing112is connected to a ground voltage (Gnd), a second status signal (e.g. a low voltage level) is outputted from the output terminal Out of the spring switch S1. Moreover, the first status signal or the second status signal outputted from the output terminal of the spring switch S1may be transmitted to the main board360through the U-shaped flexible cable150. According to the first status signal or the second status signal, the optical disc drive may judge whether the tray110is in the tray-out status or the tray-in status.

FIGS. 4A and 4Bschematically illustrate a circuit for detecting the operating status of the tray of the optical disc drive according to a second embodiment of the present invention. A spring switch S2is disposed on the main board460. A first end of the spring switch S2is fixed on the main board460. A resistor R is connected between the first end of the spring switch S2and a source voltage Vcc. In addition, the first end of the spring switch S2is also served as the output terminal Out of the spring switch S2. A second end of the spring switch S2is suspended and extended outside the main board460. As shown inFIG. 4A, in a case that the tray110is in the tray-out status, the second end of the spring switch S2is not contacted with any object. Meanwhile, a first status signal (e.g. a high voltage level) is outputted from the output terminal Out of the spring switch S2.

Whereas, as shown inFIG. 4B, in a case that the tray is in the tray-in status, the second end of the spring switch S2is compressed by the tray110and contacted with an inner surface of the casing112. Since the casing112is connected to a ground voltage (Gnd), a second status signal (e.g. a low voltage level) is outputted from the output terminal Out of the spring switch S2. According to the first status signal or the second status signal, the optical disc drive may judge whether the tray110is in the tray-out status or the tray-in status. It is noted that the part of the tray110to compress the spring switch S2is made of a non-conductive material (e.g. a plastic material).

FIGS. 5A and 5Bschematically illustrate a circuit for detecting the operating status of the tray of the optical disc drive according to a third embodiment of the present invention. A spring switch S3is disposed on the daughter board518. A first end of the spring switch S3is fixed on the daughter board518. A resistor R is connected between the first end of the spring switch S3and a source voltage Vcc. In addition, the first end of the spring switch S3is also served as the output terminal Out of the spring switch S3. A second end of the spring switch S3is suspended and extended outside the daughter board518. As shown inFIG. 5A, in a case that the tray110is in the tray-out status, the second end of the spring switch S3is not contacted with any object. Meanwhile, a first status signal (e.g. a high voltage level) is outputted from the output terminal Out of the spring switch S3.

Whereas, as shown inFIG. 5B, in a case that the tray is in the tray-in status, the second end of the spring switch S3is contacted with a conducting zone of the main board560in order to receive a ground voltage (Gnd). Meanwhile, a second status signal (e.g. a low voltage level) is outputted from the output terminal Out of the spring switch S3. Moreover, the first status signal or the second status signal outputted from the output terminal of the spring switch S3may be transmitted to the main board560through the U-shaped flexible cable150. According to the first status signal or the second status signal, the optical disc drive may judge whether the tray110is in the tray-out status or the tray-in status.

However, those skilled in the art will readily observe that numerous modifications and alterations of the third embodiment may be made while retaining the teachings of the invention. For example, the spring switch S3may be disposed on the main board560, and the daughter board518may be equipped with a conducting zone having the ground voltage (Gnd). In such configuration, the purpose of detecting the operating status of the tray110is also achieved.

FIGS. 6A and 6Bschematically illustrate a circuit for detecting the operating status of the tray of the optical disc drive according to a fourth embodiment of the present invention. A spring switch S4is disposed on the daughter board618. A first end of the spring switch S4is fixed on the daughter board618. A resistor R is connected between the first end of the spring switch S4and a ground voltage Gnd. In addition, the first end of the spring switch S4is also served as the output terminal Out of the spring switch S4. A second end of the spring switch S4is suspended and extended outside the daughter board618. As shown inFIG. 6A, in a case that the tray110is in the tray-out status, the second end of the spring switch S4is not contacted with any object. Meanwhile, a first status signal (e.g. a low voltage level) is outputted from the output terminal Out of the spring switch S4.

Whereas, as shown inFIG. 6B, in a case that the tray is in the tray-in status, the second end of the spring switch S4is contacted with a conducting zone of the main board660in order to receive a source voltage Vcc. Meanwhile, a second status signal (e.g. a high voltage level) is outputted from the output terminal Out of the spring switch S4. Moreover, the first status signal or the second status signal outputted from the output terminal of the spring switch S4may be transmitted to the main board660through the U-shaped flexible cable150. According to the first status signal or the second status signal, the optical disc drive may judge whether the tray110is in the tray-out status or the tray-in status.

However, those skilled in the art will readily observe that numerous modifications and alterations of the fourth embodiment may be made while retaining the teachings of the invention. For example, the spring switch S4may be disposed on the main board660, and the daughter board618may be equipped with a conducting zone having the source voltage Vcc. In such configuration, the purpose of detecting the operating status of the tray110is also achieved.

From the above description, the limit switch used in the conventional optical disc drive is replaced by the cost-effective spring switch of the optical disc drive of the present invention. Consequently, the fabricating cost of the optical disc drive is reduced while achieving the purpose of detecting the operating status of the tray.