JPS6155187B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical or magnetic disk device, and more particularly to a device capable of rapidly and accurately feeding a disk in the radial direction.

Video discs are generally formed in the form of a spiral track so that one frame of video signal corresponds to one revolution of the track. Therefore, it is possible to record an address signal in units of frames in the vertical blanking section and use this to perform an address search at relatively high speed. By the way, conventional video disk devices have only one motor for moving the reading head in the radial direction of the disk. Therefore, by driving one motor at low speed, normal feeding in the disk radial direction is achieved, and by driving this motor at high speed, high speed feeding for searching in the disk radial direction is achieved, or Alternatively, the feed speed is changed by keeping the motor speed constant and converting the speed using a clutch mechanism. For this reason, it has been difficult to perform speed changes quickly and smoothly.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a disk device that can quickly change the feed speed in the disk radial direction.

To achieve the above object, the present invention includes: a disk rotating device for rotating a disk at a predetermined speed; a writing and/or reading device, that is, a head portion, for writing signals to or reading signals from the disk; a support, e.g. a support substrate, of the writing and/or reading device; a longitudinal moving body, e.g. a belt or rack, juxtaposed to the support; a first motor 25 and a first pulley, for example in an embodiment, engaged with said moving body to displace itself relative to said moving body and transport said writing and/or reading device in the radial direction of said disk; 1st like 26
a feed drive device; and a feed drive device that is attached to a fixed part separate from the support body, and that is driven to displace the movable body and engaged with the movable body via the first feed drive device. engaged with the movable body to displace the support and send the writing and/or reading device in the radial direction of the disk, and set to perform feeding at a speed different from the feeding speed by the first feeding drive device; For example, the second motor 27 and the second pulley 28 of the embodiment
a second feed drive device such as the above, and the disk can be fed in the radial direction by either the first feed drive device or the second feed drive device. It is related to equipment.

According to the present invention, the first feed drive device includes:
It is attached to the support body that is fed in the radial direction, the second feed drive device is fixedly arranged, and a common movable body such as a belt or rack is engaged with both of them, so that the first speed can be achieved with a relatively simple structure. It becomes possible to convert from feeding at a second speed to feeding at a second speed and vice versa. Therefore, it becomes possible to perform a search quickly and smoothly.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, which shows the principle of a disk player according to an embodiment of the present invention, a disk motor 2, a turntable 3, and a clamper 4 are provided as a disk rotation device for rotating a disk 1 at, for example, 1800 rpm. It is being The optical reading device 5 attached to the support substrate 32 includes a laser light source 6 consisting of a He-Ne laser tube, a concave lens 7, a diffraction grating 8, a beam splitter 9, a 1/4λ plate 10, a fixed mirror 11, and a rotating mirror. 12, condensing lens 13,
It consists of a half mirror 14, a main beam detector 15, and a sub beam detector 16. The beam emitted from the laser light source 6 of this reading device 5 is transmitted through a concave lens 7
to the diffraction grating 8, where the main beam 17
and a sub beam (not shown). The main beam 17 and sub beams are projected onto the disk 1 via a beam splitter 9, a 1/4λ plate 10, a fixed mirror 11, a rotating mirror 12 as a beam displacement device, and a condensing lens 13. beam 17
The reflected beam 18 and the reflected beam of the sub beam are:
Condensing lens 13, rotating mirror 12, fixed mirror 1
The reflected beam 1 of the main beam reaches the half mirror 14 via the 1,1/4λ plate 10 and the beam splitter 9.
8 is detected by the main beam detector 15, and the reflected beam 19 of the sub beam is detected by the sub beam detector 16. In this embodiment, information is read by the reflected beam 18 of the main beam 17, and focus detection is performed by the change of the beam spot on the main beam detector 15, that is, the detection of the focus between the condenser lens 13 and the disk 1. The interval is detected, and the beam position for tracking is detected by the reflected beam 19 of the sub-beam.

The reading device 5 as described above is supported by a support substrate 32 as a support body to constitute a reading head, and the support substrate 32 is guided by first and second guide rails 20 and 21 extending in the radial direction of the disk 1. and is movable in the radial direction. Reference numeral 22 denotes a belt as a moving body arranged in parallel to the support substrate 32. The belt 22 is connected to a left pulley 23 arranged oppositely.
and the right pulley 24, extending in the radial direction of the disk. In this embodiment, the right pulley 24 is a fixed pulley, and the left pulley 23 is a displaceable pulley attached to a tensioning lever 29. The lever 29 is rotatable about a shaft 30, and is biased counterclockwise in FIG. 1 by a spring 31.

In the disk player of this embodiment, a first motor 25 is fixed to the support substrate 32 of the optical reading device 5 as a first feeding drive device for feeding the optical reading device 5 in the radial direction. A first pulley 26 is connected to 25 via a reduction gear 33. As shown in FIG. 2, the first pulley 26 is wound with a belt 22 as a movable body formed in an endless form using wire, and a part of the belt 22 is fixed to the pulley 26 with a fixing member 34. There is. Therefore, when the pulley 26 is rotated by the motor 25 while the belt 22 is prevented from moving, the pulley 26 is rotated by the motor 25.
Since it is impossible to wind the belt 22 at a fixed position, the belt 22 is wound on one side of the pulley 26.
Wind up belt 1 on the other side of pulley 26.
0 from the pulley 26, the pulley 26 moves to the left or right, and the motor 25 and the support board 3
2 also follows and moves to the left or right. The second pulley 28 is designed so that frictional resistance is generated such that the second pulley 28 does not rotate under the tension of the belt 22 corresponding to the force necessary to send the head consisting of the support substrate 32 and the reading device 5 in the radial direction of the disk. Pulley 2
A gear 27a, a motor 27, etc. are coupled to the shaft 8.

The belt 22 is also wound around a second pulley 28 disposed at a fixed position in the same manner as the first pulley 26 shown in FIG. The second pulley 28 is coupled to a second motor 27 as a second feed drive device via a reduction gear 27a.
is fixed to a fixed part separate from the movable support substrate 32, so even when the second motor 27 is driven, the second pulley 28 does not move like the first pulley 26. Rotate in a fixed position. The support substrate 32 coupled via the belt 22 and the first pulley 26 is movable, so that when the second pulley 28 rotates, it winds the belt 22 on one side of the pulley 28 and unwinds it on the other side. The belt 22 is fed out, and the belt 22 moves in the left-right direction, and the support substrate 32 follows and moves in the left-right direction. At this time, there is frictional resistance such as gear 33 and rotation loss in the rotation transmission mechanism of the first pulley 26.
Since this abrasion resistance is greater than the force required to radially feed the supporting substrate 32 and the parts attached thereto, the movement of the belt 22 causes the first pulley 2 to
6 rotates and the support substrate 32 becomes impossible to move.

This device is configured such that the second motor 27 moves the support substrate 32 in the radial direction of the disk at high speed, and the first motor 25 normally feeds the support substrate 32 in the radial direction of the disk. .
Accordingly, if a known radial feed signal from line 37 is fed to first motor 25 via first motor control circuit 38, first motor 25 moves support substrate 32 in the disk radial direction. send to
The first motor control circuit 38 operates the first motor 25 in response to a play signal given from a line 35 based on manual operation, and operates the first motor 25 based on a play command signal given from a line 36 based on an automatic search. to drive the first motor 25.
The second motor 27 is connected via line 39 to a second motor control circuit 42 when the second motor control circuit 42 is controlled with a manually operated fast forward signal supplied from line 41 or Fast-forward drive is performed when controlled by a fast-forward command signal during automatic search supplied from.

The disk 1, which is fixed on the turntable 3 by the clamper 4, has an optical recess, that is, a width of about 1 μm, a depth of about 1/4λ (here, λ is the wavelength of the laser beam), and a length of 1.5 to 6 μm. Information such as a video signal or an audio signal is recorded on a spiral track 44 by FM using bits 43, and generally consists of a transparent resin layer having an uneven surface corresponding to the pits 43 and a transparent resin layer on the uneven surface of the resin layer. It consists of a coated reflective film and a protective film that protects the reflective film. Further, a video signal in the form of a television signal is recorded on the disk 1 so that one frame per rotation is recorded, and an address signal is recorded in the vertical blanking section.

Therefore, the present device is configured to automatically search based on the address signal, and an address detection circuit 46 is coupled to the output line 45 of the main beam detector 15. The address detection circuit 46 detects the address signal recorded in the vertical blanking interval, and sends the result to a comparison calculation circuit 47 comprised of a microcomputer. Comparison calculation circuit 4
A preset address circuit 48 is connected to 7.
This preset address circuit 48 sends a signal corresponding to a search address (target address) specified by a push button switch or the like to a comparison calculation circuit 47. Now, if the preset address (search address) preset by the preset address circuit 48 is A, and the detected address (current address) detected by the address detection circuit 46 is B, then the comparison calculation circuit 47 calculates A.
and B, and outputs various control signals. Further, the comparison operation circuit 47, that is, the microcomputer, sends a signal to the line 49 that commands forward direction feeding when A is larger than B, and commands backward direction feeding when A is smaller than B.

A time setting circuit 50 using a microcomputer is provided in order to first perform a search in fast forward mode when the difference between A and B is large, that is, in this embodiment, |A-B|≧50. . This time setting circuit 50 is a circuit that determines the time required to move the head, that is, the support substrate 32 and the reading device 5, in the fast forward mode by a distance in the disk radial direction corresponding to the difference between A and B. The output of this time setting circuit 50 is given to the second motor control circuit 42, and the second
The motor 27 is driven.

As described above, when the substrate 32 is fed in the radial direction by a predetermined amount in the fast-forward mode for the time set by the time setting circuit 50, the fast-forward mode is automatically terminated. During this fast-forward remote mode, tracking detection using the sub beam 19 is impossible, but when the fast-forward mode ends, tracking detection using this sub beam becomes possible. In this embodiment, the sub beams include a first tracking beam 19a projected toward the outside of the pit 43 and a second tracking beam projected toward the inside of the pit 43, as shown in FIG. 19b, and the tracking signal is generated by detecting the reflected beams 19 of these two beams 19a and 19b with two sub-beam detectors 16, performing AM detection on them, and inputting the detection output to an error amplifier. obtain by something. and,
The output of this error amplifier is applied by line 51 to the coil of a well-known galvanometer-type beam displacement device consisting of a rotating mirror 12 and a drive 52, the rotating mirror 12 being arranged to reduce the error output to zero. controlled by. That is, the main beam 18 is controlled so as to be located at the center of the pit 43. Furthermore, secondary beams 19a, 19
The error output of the reflected light b is supplied to the line 37 via a low-pass filter and an amplifier, and is also used to drive the first motor 25.

After finishing the fast forward mode, rotate mirror 1 as described above.
When signals are read from disk 1 under tracking control in step 2, it is also possible to detect address signals. Then, the current address, that is, the detected address B
If the search address, that is, the preset address A, completely matches, the search end circuit 53 is operated by the A=B signal obtained from the comparison calculation circuit 47, and the search end circuit 53 is activated to notify the end of the search or to automatically start the device. Stop.

After the fast-forward mode, generally A=B does not hold, but |A-B|<50 almost always holds. That is, the current address B after fast forwarding is within 50 addresses (50 tracks) of the target address A, that is, the search track. In this way, when |A-B| And beam 17
A pulse having a voltage value for jumping the track pitch in the radial direction by a unit track pitch is generated at a predetermined period. Jump pulse is reverse current blocking diode 5
Known mirror drive device 5 in galvanometer configuration via 5
The main beam 17 and sub beams 19a and 19b are sent in the disk radial direction by one track pitch by rotating the mirror 12 in response to the voltage of the jump pulse. By the way, in order to accurately perform this feeding, a counter 56 is provided in the microcomputer, and the value of |A-B|<50 obtained from the comparison calculation circuit 47 is
is memorized. A counter 58 is provided to count the jump pulses generated from the jump pulse generation circuit 54, and the outputs of both counters 56 and 58 are compared in a comparator circuit 59. When both counts are equal, that is, the beam is increased by A−B. When the signal is sent, the comparator circuit 59 outputs a signal that prevents the operation of the jump pulse generation circuit 54, the jumping mode ends, and the track deviation (address deviation) caused by the fast forward mode is caused by the action of the rotating mirror 12 due to the jump pulse. Corrected and accurate automatic search. In addition, in this jump feed mode, the first motor control circuit 38 operates, the first motor 25 is in an operable state, and the error output based on the reflected light of the sub beams 19a and 19b is converted into a signal passed through a low-pass filter. Driven. However, since the jumping period is short, in reality the first motor 2
5 hardly participates in feeding during the jumping mode. However, in cases where the rotation angle of the mirror 12 is inappropriate for jumping, the motor 25 enters a normal feeding mode and the mirror 12 is then placed in a position where jumping is possible.

Next, address retrieval by the apparatus shown in FIG. 1 will be explained in more detail with reference to the flowchart shown in FIG. 4 and the beam trajectory shown in FIG. 3. First, when it is desired to search for search address A, a search start command is issued as shown by symbol 61 in FIG. 4, and search address A is preset as shown by symbol 62 using preset address circuit 48. As a result, the search proceeds according to a predetermined program of the microcomputer. That is, first symbol 6
In order to perform address detection as shown in 3, the disc player is operated normally and the current address B is detected by the address detection circuit 46. Since the comparison calculation circuit 47 is provided with a counter for temporarily storing the detected (current) address B, the detected address B is entered into the counter as shown by symbol 64 in FIG. As a result, the search address A and the detection address B are input to the comparison calculation circuit 47, so that
Perform the operation A-B as shown by symbol 65, A-B
>0, A-B<0, or A-B=0. And if A-B=0, symbol 66
The search is complete as shown. Also, A-B>0
In this case, since the search address A is currently larger than the address B, a high level signal is sent, for example, to the first motor control circuit 38 and the second motor control circuit via the line 49 in order to carry out the forward feeding indicated by symbol 67. circuit 42 and jump pulse generation circuit 54
and set each to send the beam in a radial forward direction. Conversely, in the case of A-B<0, in order to perform the processing of symbol 68, for example, a low level signal is sent to the first motor control circuit 38, the second motor control circuit 42, and the jump pulse generation circuit 54. each set to send the beam in the radial reverse direction.

Next, as shown by symbol 78, it is determined whether |A-B| is greater than or less than 50. This 50
is the number of tracks (number of addresses) on which the beam can be sent in the radial direction of the disk only by the rotating mirror 12.

As a result of the above calculation, if |A−B|≧50, in order to perform time setting and fast forwarding as shown in symbol 69,
The time setting circuit 50 calculates and determines a fast forward time width corresponding to the value of |A-B|, and operates the second motor control circuit 42 and the second motor 27 only during this time width. When the motor 27 is driven, the belt 22 moves as described above, and the support substrate 32 and the reading device 5 are sent in the forward direction following this movement.

When the fast-forward driving is completed, address detection is performed again as shown by symbol 63, and the current address B at this point in time is determined. Also, the detected (current) address B is written into the address counter of the comparison arithmetic circuit 47 in the same way as before the start of fast forwarding. Next, as shown by symbol 65, the magnitude relationship between A and B is judged again, forward feed or reverse feed is determined, and each feed mechanism is put into a corresponding control state. Next, as shown by symbol 78, |A-B|>50 is determined again. In this case, since the beam has come close to the search address A due to fast forwarding, in most cases the result is NO, and the comparison calculation circuit 47 obtains an output of |A-B|<50. Then, in order to process symbol 79, the result of |A-B|, for example, |A-B|=C=
4 is written to the microcomputer counter 56. Further, in response to a signal indicating |A-B|<50, a jump pulse generating circuit 54 generates a jump pulse having a voltage value that allows jump (transition) of a unit track at a predetermined period. When the first jump pulse is generated, the mirror 12 rotates corresponding to one track pitch, and the main beam 17 and the sub beams 19a and 19b move from the track T ₀ as shown by the chain line 57 in FIG. truck
Move to _T1 . In this case, the tracking control circuit is in operation, so that after the beam jumps onto track _T1 , it scans on track _T1 . Tracking on track _T1 can be achieved in about 2H (horizontal scanning period), so after about 2H has elapsed, the next jump pulse is generated and the mirror 12 moves the beam to the next track _T3 . In this way C
A jump pulse of =4 is generated and the beam is sent to search track _T4 , ie, search address A. In this case, in order to make the determination of symbol 76, the jump pulses are counted by the counter 58, the value of the counter 56 is compared with the value of the counter 58 by the comparator circuit 59,
The comparison circuit 59 determines that the predetermined jumping has been completed, that is, that |A-B|=C of the counter 56 and the count value of the jump pulse of the counter 58 match.
The operation of the jump pulse generation circuit 54 is stopped. Thereafter, address detection is performed again, the search address A and the current address B are compared, A=B is confirmed, and the search end circuit 53 outputs an end signal.

Incidentally, the stepwise jump as shown in Fig. 3 is 100 msec while the disk 1 rotates once (for example, 33 msec).
50 addresses (tracks) so more than 50 times is possible
A jump of 1 is easily achieved during one rotation of the disk 1.

As is clear from the above, according to this example,
The first motor 25 for normal feeding and the second motor 27 for rapid feeding are connected to a common belt 22, so that the first motor 25 and the second motor 27 can be connected to each other without a switching operation using a clutch mechanism or the like. Since the support substrate 32 can be selectively moved with the motor 27, high-speed searches can be performed relatively easily.

Also, when the difference between search address A and current address B is less than 50, the beam is sent using a jump pulse, and it is sent in units of one track (one address), so search address A can be quickly retrieved. Moreover, it is possible to search accurately. In other words, the search can be completed within a period of time equal to the time for fast forward mode (for example, 1 second) plus the time for one rotation of the disk (for example, 33 msec).

Although the embodiments of the present invention have been described above, the present invention is not limited thereto and can be further modified. For example, as shown in FIG. 5, a rack 22a is provided in place of the belt 22, a first pinion 26a is engaged in place of the first pulley 26, and a second pinion is engaged in place of the second pulley 28. 28a may be engaged. Further, the second motor 27 is a step motor, and the time setting circuit 50
Instead, a step number setting circuit may be provided to fast-forward a predetermined track by step operation. It is also applicable to concentric tracks. Also, while the second motor 27 is sending
The speed may be further increased by continuing the feeding at step 5. In addition, an up-down counter is provided in place of the counters 56, 58 and the comparison circuit 59, and |A-B|=C is written in advance in the up-down counter, and the jump pulse is used to count down, and when the output reaches zero, the search is considered complete. Good too. It is also applicable to writing and/or reading devices using magnetic disks.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a disk player according to an embodiment of the present invention, FIG. 2 is an enlarged front view showing the connection between the belt and pulley of FIG. 1, and FIG. 3 is an explanatory plan view of the disk. FIG. 4 is a flowchart of the search performed by the apparatus shown in FIG. 1, and FIG. 5 is a front view showing the rack mechanism as a moving body. In the symbols used in the drawings, 1 is a disk, 2 is a disk motor, 5 is a reader, 22 is a belt, 25 is a first motor, 26 is a first pulley, and 27 is a second motor. , 32 is a support substrate, and 54 is a jump pulse generation circuit.

Claims (1)

[Claims] 1. A disk rotation device that rotates a disk at a predetermined speed, and a writing and/or device for writing signals to or reading signals from the disk.
or a reading device; a support for the writing and/or reading device; a longitudinal movable body juxtaposed to the support; and a longitudinal movable body attached to the support and driven by itself relative to the movable body. a first feeding drive engaged with the movable body to displace and send the writing and/or reading device in the radial direction of the disk; Displacing the movable body by driving and displacing the support body engaged with the movable body via the first feed drive device to move the writing and/or reading device in the radial direction of the disk. a second feed drive device that is engaged with the movable body so as to feed the movable body and is set to perform a feed at a different speed from the feed speed of the first feed drive device; A disk device in which the disk can be fed in the radial direction by either the drive device or the second feed drive device. 2. The first and second feed drive devices are first and second motors, and the movable body is wound around the first and second pulleys of the first and second motors, respectively, and a part thereof 2. The disk device according to claim 1, which is an endless belt fixed to said first and second pulleys. 3. The moving body is a linear rack, and the first
The feed drive device includes a first gear that meshes with the rack and a first motor that rotates the first gear, and the second feed drive device includes a second gear that meshes with the rack and a first motor that rotates the first gear. 2. The disk device according to claim 1, further comprising a second motor that rotates a second gear. 4. The disk device according to claim 1, wherein the second feed drive device is a step feed device including a step motor.