JPH05258444A - Cartridge release control circuit - Google Patents

Abstract

PURPOSE:To unnecessitate a sensor discriminating the presence or absence of a cartridge by discriminating the lever position based on the current value of the motor driving current and controlling the motor driving current according to the result of discrimination. CONSTITUTION:A power supply means 111 of a cartridge release control circuit supplies the drive current to a motor 101. A current measurement means 112 measures the current value of the drive current. A discrimination means 113 discriminates the position of a lever 102 based on the current value obtained by the current measurement means 112. A control means 114 directs the drive current supply according to the position of the lever 102 obtained by a discrimination means 113 to the power supply means 111, releasing the cartridge with the cartridge release mechanism operated. In this case, when the motor 101 is the DC motor, the torque differs according to the rotation state, the discrimination depends on the intensity of the drive current without using the sensor directly discriminating the cartridge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cartridge and a spindle motor when a cartridge containing a storage medium such as a magneto-optical disk is ejected from a drive device for writing / reading information to / from the storage medium. The present invention relates to a cartridge release control circuit that controls a mechanism for releasing the locked state of the cartridge.

In recent years, information processing devices such as personal computers have become more sophisticated, and along with this, the use of drive devices having a large-capacity magneto-optical disk as a storage medium has been used as auxiliary storage devices for personal computers. Is desired. Therefore, there is a demand for miniaturization of the drive unit for the magneto-optical disk, and miniaturization of each part such as a mechanism for releasing the cartridge from the spindle motor (hereinafter referred to as a cartridge releasing mechanism) is required. There is.

[0003]

2. Description of the Related Art FIG. 6 (a) is a top view of a cartridge releasing mechanism, and FIGS. 6 (b) and 6 (c) show a cartridge releasing mechanism with a cartridge mounted and a cartridge released, respectively. A side view is shown.

In FIG. 6A, the spindle motor 10
Reference numeral 7 denotes the base plate 1 via the cam mechanisms 611a to 611d provided on the both sides of the base plate 104.
It is held at 04. A claw 612 is provided on the motor 101 side of the base plate 104, and the motor 101 rotates the lever 102 and pushes the claw 612 to move the base plate 104.

The above-mentioned cam mechanism 611 corresponds to the moving-direction changing member 105, and the spindle motor 10
The pins protruding from 7 are as shown in Fig. 6 (b) and (c).
The spindle motor 107 is configured to move downward by moving along the oblique cam groove in accordance with the movement of the base plate 104.

Here, the spindle motor 107 is composed of a motor section and a rotary table, and a magnet is attached to the upper surface of the rotary table. Further, the magnet attracts the metal piece attached to the cartridge 106 to chuck the cartridge 106 on the turntable and rotate the magneto-optical disk housed in the cartridge 106.

Therefore, as described above, by moving the spindle motor 107 in the direction of the arrow B, chucking by the magnet and the metal piece is removed, and the cartridge 106 is released from the spindle motor 107. Thereafter, the cartridge 106 is transferred to the motor 10 by another mechanism that is linked to the cartridge releasing mechanism.
It is discharged to the 1st side.

The base plate 104 described above is provided with a guide groove 613 for restricting the moving direction, and a pin 614 fixed to the housing is provided with this guide groove 613.
It is embedded in. Similarly, the spindle motor 107
Is provided with a guide pin 615 for restricting the movement direction of the spindle motor 107 and penetrates the spindle motor 107 and is fixed to the housing.

Further, in FIG. 6, a spring 616 corresponds to the urging member 103, and both ends thereof are attached to the above-mentioned base plate 104 and housing, respectively.
The base plate 104 is urged toward the motor 101 according to the movement of the base plate 104. The locking member 617 is shown in FIG.
As shown in (c), the base plate 104 is the cartridge 1
When moving to the release position of 06, by engaging the tab of the locking member 617 with the opening 618 provided in the base plate 104, the base plate 104 is engaged against the biasing force of the spring 616 described above. It is configured to stop.

Conventionally, the releasing operation by the above-mentioned cartridge releasing mechanism has been controlled by the cartridge releasing control circuit shown in FIG. However, in FIG. 7, the cartridge releasing mechanism is shown in a simplified manner.

In FIG. 7, the cartridge release control circuit is a sensor 711 for determining the presence or absence of the cartridge 106.
Depending on the output of the microprocessor (MPU) 721
However, the motor drive circuit 722 that supplies a drive current to the motor 101 is controlled.

The sensor 711 described above is the cartridge 1
When the cartridge 106 is mounted, it is arranged at a position where it contacts the cartridge 106 or its holding member, and the presence or absence of the cartridge 106 is directly determined depending on whether the cartridge 106 is in contact with the sensor 711. Is sent to the microprocessor 721.

When starting the release operation of the cartridge 106, the microprocessor 721 determines whether or not the cartridge 106 is in the mounted state based on the above-mentioned detection signal, and when it is in the mounted state, the base plate An instruction to supply a drive current for rotating the lever 102 to the 104 side is sent to the motor drive circuit 622. In addition, the microprocessor 721 starts the release operation of the cartridge 106, and then the sensor 711 and the cartridge 106.
When a detection signal indicating that and are not in contact is input,
When it is determined that the discharging operation including the releasing operation of the cartridge 106 is completed, the motor driving circuit 722 is instructed to stop the driving current to the motor 101.

[0014]

As described above, conventionally, the presence / absence of the cartridge 106 is determined by using the sensor 711, and the microprocessor 7 is determined according to the determination result.
21 controls the motor drive circuit 722 to control the releasing operation of the cartridge.

Therefore, in addition to the circuit for directly controlling each part of the cartridge releasing mechanism shown in FIG.
It is necessary to provide wiring for supplying power to the circuit for driving 11 and the sensor 711. Therefore, the circuit scale of the cartridge release control circuit becomes large, and
A space for installing the sensor 711 is required inside the drive device, which is an obstacle to downsizing of the drive device.

It is an object of the present invention to provide a cartridge release control circuit which does not require a sensor for determining the presence / absence of a cartridge.

[0017]

FIG. 1 is a block diagram showing the principle of the present invention. According to the present invention, the lever 102 is rotated by the rotation of the motor 101, the base plate 104 biased to the lever 102 side by the biasing member 103 is moved to the opposite side of the lever 102, and the moving direction conversion member 105 is used. In the cartridge release control circuit that controls the operation of the cartridge release mechanism that releases the locked state of the cartridge 106 containing the recording medium and the spindle motor 107, the current supply unit 1 that supplies a drive current to the motor 101.
11 and current measuring means 11 for measuring the current value of the drive current
2 and the current value obtained by the current measuring means 112, the determining means 113 for determining the position of the lever 102, and the current supplying means 111 for supplying the drive current according to the position of the lever 102 obtained by the determining means 113. To the control means 114
It is characterized by having and.

[0018]

According to the present invention, the motor 101 is provided with the current supply means 111.
The current value of the drive current supplied from the current measuring means 112
The control means 114 controls the current supply means 111 according to the position of the lever 102 determined by the determination means 113 based on the measured current value.

When a direct current motor is used as the motor 101, the torque required for rotation is different depending on whether the motor 101 is freely rotating or rotating with resistance. The magnitude of the current is different. For example, when the lever 102 pushes the base plate 104, the urging member 10 acting on the base plate 104.
The biasing force of 3 acts as a resistance against the rotation of the motor 101. Therefore, from the magnitude of the drive current, the lever 1
It is possible to determine whether 02 is in a position for exerting a pressing force on the base plate 104 and whether the locked state between the cartridge 106 and the spindle motor 107 has been released. In other words, by controlling the drive current according to the determination result of the determination unit 113, the release operation of the cartridge 106 can be controlled, and the cartridge release control that does not require a sensor for directly determining the presence or absence of the cartridge. A circuit can be constructed.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 2 shows the configuration of an embodiment of the cartridge release control circuit of the present invention.

However, in FIG. 2, the cartridge releasing mechanism shown in FIG. 6 is shown in a simplified manner. In FIG. 2, a motor drive circuit 211 corresponds to the current supply unit 111, and in response to an instruction from a microprocessor (MPU) 212 corresponding to the control unit 114, supplies a drive current of a specified polarity to the motor 101. It is configured to supply to.

A resistor 221 having one end grounded is connected to the output side of the above-mentioned motor drive circuit 211, and the comparison circuit 222 determines a predetermined voltage drop V caused by the resistor 221 when a drive current flows. The comparison is made with the threshold value V _TH, and the comparison result is sent to the microprocessor 212. That is, by comparing the converted drive current to the voltage drop V with the threshold V _TH, which is configured to determine whether or not exceed the current value which the absolute value of the drive current corresponding to the threshold V _TH. When the voltage drop V that exceeds the threshold value V _TH is input, the above-mentioned comparison circuit 222 outputs a logic “1” indicating that overcurrent has been detected, and when the voltage drop V is less than or equal to the threshold value V _TH , for example. Logical "0"
May be output.

Here, when a direct current winding motor, for example, is used as the motor 101, as shown in FIG. 3, the drive current I and the torque T have a substantially proportional relationship, and the drive current I and It is known that there is an almost inverse proportional relationship with the rotation speed RPM. Here, when the rotation of the motor 101 is started, or when the lever 10 attached to the motor 101 is used.
2 is pushing the base plate 104, the motor 10
The inertia of 1 or the action of the spring 616 corresponding to the biasing member 103 serves as resistance against the rotation of the motor 101, and the torque T for rotation increases. Therefore, due to the above-described relationship, a large drive current I flows through the motor 101. Further, when the lever 102 hits the positioning member 202 provided for determining the initial position of the lever 102, resistance to rotation of the motor 101 is generated, and thus a large drive current similarly flows to the motor 101.

Therefore, it is possible to know from the magnitude of the drive current I whether or not the motor 101 is freely rotating. Further, since the rotation direction of the motor 101 can be known from the polarity of the drive current I, when there is resistance to the rotation of the motor 101, it is determined whether the resistance is due to the base plate 104 or the positioning member 202. be able to.

Here, when the motor 101 is freely rotating, the magnitude of the drive current flowing through the motor 101 is 200 mA or less, and when there is resistance, a drive current of 400 mA or more flows. Therefore, for example, if a voltage value corresponding to a drive current of 280 mA is set as the threshold value V _TH in the above-mentioned comparison circuit 222, whether the position of the lever 102 is the above-described initial position or the position where the lever 102 abuts the cartridge holding member 201, Alternatively, it is possible to determine whether or not the position is not in contact with any of these.

That is, the function of the current measuring means 112 and the judging means 113 is fulfilled by the resistor 221 and the comparison circuit 222. FIG. 4 is a flowchart showing the cartridge releasing operation. Further, FIG. 5 shows a timing chart showing the operation of the cartridge release control circuit.

In the initial state, the lever 102 is in the above-mentioned initial position, but is in abutment with the positioning member 202, and the motor 101 is not rotating. In step 401, the microprocessor 212
The motor drive circuit 211 is instructed to supply a drive current having a polarity for rotating the motor 101 clockwise. In response to this, the lever 102 starts rotating toward the base plate 104 side. At this time, the drive current flowing through the motor 101 becomes a normal drive current of 200 mA or less after a large current for starting the motor 101 flows, as shown in FIG. 5 (a). However, in FIG. 5A, the motor 101
The polarity of the drive current that rotates the is indicated as a negative polarity.

After the movement toward the base plate 104 side is started in this way, the microprocessor 212 waits for a predetermined time τ (step 402), and a timer (not shown) for detecting an abnormality in the releasing operation. No.) for a set time t (for example, 1.5 sec) to start (step 40).
3).

After that, the microprocessor 212 checks the output of the comparison circuit 222 at every time t _d (for example, 50 ms) (step 404) and determines whether an overcurrent is detected (step 405). Further, in the case of a negative determination in step 405, it is determined whether or not the timer set time t has elapsed (step 40
6) If not elapsed, return to step 404.

It takes a predetermined time (for example, about 700 ms) from the start of the rotation operation of the motor 101 until the lever 102 comes into contact with the base plate 104, and during this time, the motor 101 rotates freely. is doing. Therefore,
Time τ shorter than the above required time (eg 550ms)
It suffices to wait for that and then start monitoring the output of the comparison circuit 222. This also prevents erroneous detection of a voltage drop caused by noise or the like as an increase in drive current.

In this case, the monitoring of the output of the comparison circuit 222 is started from the time point indicated by the arrow A in FIG. 5, and the above-mentioned steps 404 to 406 are repeated, so that the comparison circuit at the time point indicated by the arrow B. The output of 222 becomes logic "1" (see FIG. 5B), the fact that overcurrent is detected is notified to the microprocessor 212, and an affirmative determination is made in step 405.

As described above, when the overcurrent is detected within the set time t of the timer, the microprocessor 212 determines that the lever 102 has moved to the position where it abuts the base plate 104, and instructs the motor drive circuit 211 to do so. And gives an instruction to stop the supply of the drive current (step 40).
7). At this time, the microprocessor 212 may wait _a predetermined time ta after the comparison circuit 222 detects the overcurrent and then instructs the motor drive circuit 211 to stop the drive current. Here, the predetermined time t _a as described above, in accordance with the movement of the base plate 104 by the lever 102, the cam mechanism 611 which corresponds to the moving direction conversion member 105, the spindle motor 107 is sufficiently moved (FIG. 6 ( (See b) and (c)), the time required until the chucking of the cartridge 106 and the spindle motor 107 is released may be set. As a result, the cartridge 106 can be reliably released from the spindle motor 107, and the cartridge 106 can be ejected by another mechanism that works in conjunction with this cartridge releasing mechanism.

Next, the microprocessor 212 causes the motor drive circuit 211 to rotate the motor 101 counterclockwise with respect to the motor drive circuit 211 in order to position the lever 102 at the initial position (in FIG. 5 (a)). Instructing to supply a positive polarity current (step 4)
08). Then, similarly to steps 402 to 406, the output of the comparison circuit 222 is monitored (steps 409 to 413).

For example, when the drive current changes as shown in FIG. 5A, at the time of arrow C, the comparison circuit 22
The output of 2 becomes logic "1" (see FIG. 5 (b)), the fact that overcurrent has been detected is notified to the microprocessor 212, and an affirmative decision is made in step 412.

In response, the microprocessor 212
Judges that the lever 102 has moved to the position where it abuts the positioning member 202 (initial position), and instructs the motor drive circuit 211 to stop the drive current (step 4).
14) The process may be terminated.

By the way, the lever 102 is attached to the base plate 104.
If the overcurrent is not detected within the set time t of the timer while rotating to the side, the motor 1
01 may have stopped or the release operation of the cartridge 106 may have failed. Therefore, in the case of a positive determination in step 406, the microprocessor 212 notifies the upper-level device (for example, the control unit of the drive device, the personal computer, etc.) of the abnormality as an error process (step 415), and then the above-described step 407. ~ The step 414 may be performed to move the lever 102 to the initial position.

On the other hand, if the overcurrent is not detected within the set time t of the timer while the lever 102 is being moved to the initial position, that is, step 41
In the case of a positive determination of 3, the microprocessor 212
When it is determined that the motor 101 is abnormal, step 4
As in the case of 15, the upper device is notified of the abnormality (step 41
6) Then, the process proceeds to step 414, the motor 101 is stopped, and then the process is ended.

In this manner, the direction of movement of the lever 102 and whether or not the motor 101 is freely rotating are judged from the polarity and magnitude of the drive current of the motor 101, and the lever 102 is moved to the base plate 104 or the positioning. It is possible to determine whether it is in a position where it abuts against the member 202 or in a position where it abuts against none of these members.

Thus, instead of directly determining the presence or absence of the cartridge 106 by the sensor, the motor 101
It is possible to determine whether or not the cartridge 106 and the spindle motor 107 are chucked based on the drive current of the cartridge 106 and control the release operation of the cartridge 106. A circuit can be constructed. Further, the circuit required for this purpose is only the resistor 221 and the comparison circuit 222, which is smaller than the circuit for driving the sensor.

Therefore, as described above, the motor 10
By controlling the release operation of the cartridge 106 based on the drive current of 1, the circuit size of the cartridge release control circuit can be reduced, and the installation space of the sensor itself and the wiring space associated with the sensor can be reduced. Since it is unnecessary, the drive device can be downsized.

Further, by limiting the time for monitoring the output of the comparison circuit 222 by using the timer, it is possible to flexibly deal with an error such as the case where the cartridge 106 is not released normally.

In order to confirm that the lever 102 is positioned at the initial position, before the step 401, the supply of the drive current of the polarity for rotating the motor 101 in the counterclockwise direction is instructed to check the overcurrent. After detecting, the processing from step 401 onward may be executed.

[0043]

As described above, the present invention provides the motor 1
The position of the lever 102 is determined based on the current value of the drive current of 01, and the drive current of the motor 101 is controlled according to the result of the determination to detect the presence or absence of the cartridge 106 directly by a sensor. Without doing so, it is possible to control the releasing operation of the locked state between the cartridge 106 and the spindle motor 107. Therefore, the cartridge release control circuit can be downsized, and the sensor installation space can be eliminated, so that a magneto-optical disk or the like can be used. The size of the drive device can be reduced.

[Brief description of drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment of a cartridge release control circuit of the present invention.

FIG. 3 is an explanatory diagram of characteristics of a motor.

FIG. 4 is a flowchart showing a cartridge releasing operation.

FIG. 5 is a timing chart showing the operation of the cartridge release control circuit.

FIG. 6 is a configuration diagram of a cartridge release mechanism.

FIG. 7 is a configuration diagram of a conventional cartridge release control circuit.

[Explanation of symbols]

 101 motor 102 lever 103 biasing member 104 base plate 105 moving direction converting member 106 cartridge 107 spindle motor 111 current supply means 112 current measuring means 113 discriminating means 114 control means 202 positioning member 211,722 motor drive circuit 212,721 microprocessor ( MPU) 221 resistance 222 comparison circuit 611 cam mechanism 612 claw 613 guide groove 614 pin 615 guide pin 616 spring 617 locking member 618 opening 711 sensor

Claims (1)

[Claims] 1. A lever (102) is rotated by rotation of a motor (101), and a base plate (104) urged toward the lever (102) by an urging member (103) moves the lever (102). To the opposite side to control the operation of the cartridge release mechanism that releases the locked state of the cartridge (106) containing the recording medium and the spindle motor (107) via the movement direction conversion member (105). In the cartridge release control circuit, a current supply unit (111) that supplies a drive current to the motor (101) and a current measurement unit (11) that measures the current value of the drive current.
2) and a discriminating means (11) for discriminating the position of the lever (102) from the electric current value obtained by the electric current measuring means (112).
3) and the supply of the drive current according to the position of the lever (102) obtained by the determination means (113), the current supply means (11).
A cartridge release control circuit comprising: a control means (114) for instructing 1).