JP2635047B2 - Information erasing / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grassland for erasing and / or reproducing information recorded on a recording medium such as a still video floppy disk, an optical disk, and other floppy disks. For example, the present invention is particularly effective when applied to erase and / or reproduce a desired signal among image signals stored in a floppy disk by an electronic still camera or the like.

[Conventional technology]

In recent years, systems such as an electronic still camera or a still video floppy disk player that records a still image signal on a floppy disk, a so-called disk pack, and reproduces the recorded image on a television screen have been developed. For recording image information on a floppy disk, information for one field is recorded on one track,
Field recording in which one image is recorded by the track alone, information of the first field in one of two adjacent tracks (for example, an outer track), and information of the first field in the other (for example, an inner track). There is frame recording in which information of two fields is recorded, and information of the first field and the second field by such a pair of tracks is used as one image.

Regarding the electronic still camera, a unified standard has already been established for the recording method and various other items. According to this, recording of an image signal on a magnetic recording medium (floppy disk) is permitted in both field recording and frame recording. Therefore, in reproducing an image, it is prescribed that data for the identification is recorded in advance so that it can be identified whether it is a field recording or a frame recording. The recording signal for this identification is called an ID signal, and is multiplex-recorded on the recording medium together with the video signal. That is, in the frame picture recorder, the data for field / frame identification is determined to be frequency-multiplexed and recorded on the video track. Frequency of the carrier for the record, 20 is 13 times (i.e., the NTSC system in the horizontal scanning frequency f _H
(4.54 KHz), the modulation method is DPSK, and the bit rate is determined so that a 4H section (H is one horizontal scanning period, the same applies hereinafter) corresponds to one bit (Nikkei Electronics 198).
See 4.7.2 etc.).

The bit allocation on the recording track is performed as shown in FIG. That is, the 4H section (ie, 1 bit section) 28H or 28.5H after the start point (all edges of the signal) of the vertical synchronization signal (V.SYNC) is used as an initial bit, and the subsequent 8H section (ie, 2 bit section) )
Are allocated for identification data of field / frame recording. The data in the 2-bit section is "00"
The case corresponds to field recording, and the case of "01" or "10" corresponds to frame recording. In the frame recording, “01” indicates that the track is the outer track of the pair of frame recording tracks, and “10” indicates that the track is the inner track. As described above, the recording of the image signal of the floppy disk in the electronic still camera is performed with the ID signal for each recording track, and the recording is performed in a form in which the field recording and the frame recording are mixed on the same floppy disk. Is often done. As is well known, one characteristic of a floppy disk is that recording information can be rewritten or erased on a desired track. However, as described above, recording is performed in a form where field recording and frame recording are mixed. When trying to erase the record of an arbitrary track on a floppy disk made, when erasing the track corresponding to the frame recording, both of the pair of tracks corresponding to the frame may be automatically erased. desirable. A still floppy disk erasing device having such a function has already been proposed by the present applicant as Japanese Patent Application No. 61-186625.

On the other hand, when erasing and / or reproducing recorded information with a head having a width corresponding to the recording track width of the recording medium,
Eccentricity in the recording medium device, expansion and contraction and deformation of the medium itself,
Or, due to the tolerance of the head position control (for example, when a different recording / reproducing machine is used) or the like, an optimum tracking state cannot be obtained, and a partial erasure remains on a side edge of the track,
Alternatively, the envelope level of the reproduced signal may not reach the optimum level. Therefore, in order to perform erasure without erasure or to secure an ideal reproduction signal level, the head is slightly displaced, and the trajectory of the relative movement of the head with respect to the recording medium or the recording medium occupied by the trajectory. It is necessary to control the head position so that the upper region takes the optimum position. To solve one of these problems, move the head across the width of the track to be erased,
A technique for performing an erasing operation by rotating the medium (floppy disk) two or more times to thereby eliminate the unerased portion is already known in Japanese Utility Model Publication No. 57-21133.

[Problems to be solved by the invention]

When the head is moved in the track width direction to perform ideal erasure or reproduction as described above, it is desirable that the movement be minute. However, if such minute displacements are enabled, a new problem arises in that high-speed head access becomes difficult. That is, for example, if the head feed mechanism is configured to be able to feed the head in small steps so that the displacement in minute units functions to perform high-precision tracking, the head will move at a high speed when moving the head between tracks. It becomes difficult to move, and high-speed access cannot be performed. This is because in order to secondarily (and consequently) obtain a relatively long feed operation such as movement between tracks with a feed mechanism having a resolution capable of minute displacement, a very multi-stage or high rotation primary is generally used. This is because a driving operation is required.

The present invention has been made in view of such circumstances, and an object of the present invention is to enable the head to be displaced in minute units without sacrificing the head access speed, and to perform an erasing operation in which no erasure remains, An object of the present invention is to provide an information erasing / reproducing apparatus capable of smoothly performing accurate and fine tracking control and the like.

[Means for solving the problem]

The present invention solves the above problems and achieves the object,
The following measures were taken. That is, as shown in FIG. 1, a head 200 capable of functioning as at least an erasing head and a reproducing head with respect to a recording track of the recording medium 100, and a head provided to be displaceable while supporting the head 200 A carriage 300 and a driving source for generating a driving force for giving a displacement to the head carriage 30
400, the secondary displacement is zero or a small amount with respect to a predetermined amount of the primary displacement for converting the primary displacement as the input transmitted from the drive source 400 into the secondary displacement as the output provided to the head carriage 300. A plurality of stagnation characteristic portions and a displacement conversion element 500 configured to exhibit a displacement conversion characteristic including a feed characteristic portion that obtains a secondary displacement larger than the stagnation characteristic portion for a predetermined amount of the primary displacement; and In the erasing or reproducing operation mode, the head is displaced in an area on the recording medium corresponding to a section including at least a part of the stagnant special part corresponding to the track to be erased or reproduced and the feed characteristic part connected to the characteristic part. At this time, the erasing operation is performed on the head with respect to this area,
Or a control means 600 for performing a reproducing operation with tracking control for selecting a head position within this area.
Was provided. Reference numeral 700 denotes a motor for rotating the recording medium 100 at a high speed.

[Action]

By taking such means, the following effects are exhibited. That is, for example, when erasing or reproducing information recorded on a recording medium,
By controlling the driving source 400, when the head carriage 300 is displaced in a region including at least a part of the stagnation characteristic portion and the feed characteristic portion of the displacement conversion element 500, by the head 200 displaced by the head carriage 300, At the time of erasing, erasing can be performed for the entire area enlarged than the track to be erased,
At the time of reproduction, a highly accurate on-track state can be generated. When the head 200 is moved between tracks, the driving means 400 is controlled by the control means 600, and when the head carriage 300 is displaced in the area of the feed characteristic portion of the displacement conversion element 500, the head displaced by the carriage 300 200 will immediately move to the predetermined track.

〔Example〕

FIG. 2 is a block diagram showing an electric circuit section of an embodiment in which the present invention is applied to a still video floppy disk player. In the figure, a plurality of annular tracks 2 are formed concentrically on a still video floppy disk 1, and signals are transferred to and from the tracks 2 by a two-channel type multi-head 3. The head 3 includes an inner head 3a located on the inner side with respect to the radial position of the floppy disk 1, and an outer head located on the outer side.
Reference numeral 3b denotes an inline head in which the head gaps are arranged so as to be aligned in the radial direction. The inner head 3a and the outer head 3b are connected to the first
Terminal 4a and the second terminal 4b. The switching circuit 4 is provided with a third terminal 4c, a fourth terminal 4d, a fifth terminal 4e (grounded) and a sixth terminal 4f in addition to the first and second terminals 4a and 4b. It is. The switching circuit 4 is adapted to selectively switch the connection relationship between the first and second terminals and the third to fifth terminals by an external signal applied to the sixth terminal 4f. It is. Note that the sixth terminal 4f is actually a group of a plurality of terminals adapted to a plurality of external signal input lines. A third terminal 4c of the switching circuit 4 is connected to an input terminal of a reproducing circuit 5 for amplifying a signal detected by the head 3 to a predetermined level. One output terminal of the reproducing circuit 5 is connected to an input terminal of a video reproducing circuit 6 for performing signal processing for demodulating a signal relating to a video and displaying the signal on a monitor, and the output terminal of the video reproducing circuit 6 is connected to a video output terminal 7. It is connected to the. The other output terminal of the reproduction circuit 5 outputs a data signal (ID signal) multiplexed and recorded together with the video signal as described above.
Is connected to the input terminal of a data demodulation circuit 8 for demodulating the data. The data of the data demodulation circuit 8 is supplied to the control circuit 9. Further, in order to perform tracking control of the head based on the envelope of the reproduction signal, the output of the reproduction circuit 5 is directly supplied to the control circuit 9.

On the other hand, a video input terminal 10 for receiving a video signal to be recorded from the outside is provided.
Is connected to the first input terminal 11a. The recording / amplifying circuit 11 has a second input terminal 11b and a third input terminal 11c in addition to the first input terminal 11a. The recording / medium circuit 11 responds to a signal T2 from the stimulus circuit 9 given to a third input terminal 11c, and responds to the signal T2 from the first input terminal 11c.
The video signal supplied to a at a predetermined level F suitable for recording
Output as an M signal or the second input terminal 1
It includes a known amplification circuit, modulation circuit, changeover switch circuit, and the like configured to selectively perform an operation of amplifying the erase signal supplied to 1b to a sufficiently high level and outputting the amplified signal. Further, the control circuit 9 receives an instruction of an erasure or reproduction track number, an erasure or reproduction operation instruction, and various other instruction signals through the instruction signal input terminal 12 to the apparatus, and has one function corresponding to these inputs. In addition to receiving the data signal ID from the data demodulation circuit 8, the sixth terminal 4f of the switching circuit 4
The third input terminal 11c of the amplifier circuit 11 is configured to include, for example, a microcomputer adapted to supply timing signals T1 and T2. The control circuit 9 further includes a position control signal PC for controlling the position of the head 3.
To the motor drive circuit 13. The motor drive circuit 13 is provided to supply electric power to the motor 14 so as to rotate the motor 14 by an angle corresponding to the signal PC in response to the position control signal PC. The rotational displacement of the output shaft of the motor 14, ie, the primary displacement, is converted into a linear displacement, ie, a secondary displacement via a displacement transmission mechanism 15, which is abbreviated by a broken line in FIG. It is composed of In the present invention, a characteristic mechanism is adopted as the displacement transmission mechanism 15, as described later. In addition,
A second input terminal 11b of the recording / amplifying circuit 11 has an erasing signal generating circuit for generating an erasing signal which is a relatively high level AC signal for erasing the recording of the floppy disk 1.
It is configured to provide 16 outputs.

The operation of the electric circuit section of the apparatus having the above configuration will be described. First, it is assumed that a command for “erasing the nth track” is input to the control circuit 9 via the command signal input terminal 12 by an operation switch or the like (not shown). The control circuit 9 responds to the output of the motor drive circuit 13 with a position control signal PC for moving the inner peripheral head 3a of the head 3 to the n-th track position based on this input, The head 3 is moved so that the head 3a is located on the n-th track.
The current position of the head 3 can be identified in the control circuit 9 by a known means such as a head position encoder or a head position counter based on a head movement signal. When the inner peripheral head 3a is located on the n-th track, the first terminal 4a and the third terminal 4c of the switching circuit 4 are connected by the timing signal of the control circuit 9, and the detection output of the inner peripheral head 3a is output to the reproducing circuit. 5 is supplied. At this time, if a monitor is connected to the terminal 7, the recorded image on the nth track is observed. The other output of the reproduction circuit 5 is provided to a data demodulation circuit 8. The data demodulation circuit 8 demodulates the data signal ID obtained by multiplexing and recording the image signal by DPSK modulation as described above.
Give to. As described above, according to the standard of the electronic still camera, if 2-bit data indicating field recording or frame recording is “00”, the track (in this case, the n-th track) is a track on which field recording is performed, and “ If it is "01", it is the outer track of the frame recording tracks, and if it is "10", it is the inner track of the frame recording tracks. The control circuit 9 identifies the demodulated data as described above, and outputs the timing signals T1, T2 and the position control signal PC based on the data.

As a first case, consider a case in which the n-th track is identified as a field record. In this case, the first terminal 4a and the fourth terminal 4d of the switching circuit 4 are connected by the timing signal T1 without moving the head position by the position control signal PC. The operation of the recording / amplifying circuit 11 is switched by the timing signal T2. That is, a first input terminal for receiving a signal from the video input terminal 10
11a is switched to an insulated state, and an erasing signal from the erasing signal generating circuit 16 is received by the second input terminal 11b, and is switched to an operation mode in which the signal is amplified to a level sufficient for the erasing operation and output. Close. Accordingly, the amplified erase signal is supplied to the inner peripheral head 3a via the fourth terminal 4d and the first terminal 4a of the switching circuit 4, whereby the recording information of the n-th track is recorded with the rotation of the proppy disk 1. Is erased all around. In the present invention, the erase operation is repeated for one track by moving the head in order to prevent the occurrence of the unerased portion. This will be described in detail later. The erasing operation for the field recording track is now completed, and the control circuit 9 returns to the standby state.

Next, as a second case, consider a case where the n-th track is identified to be the outer track of the frame recording tracks. In this case, it becomes as follows. First, the erasure of the n track itself is performed in exactly the same manner as the erasure of the field recording track. Next, based on the position control signal PC of the control circuit 9, the motor drive circuit 13, the motor 14, and the displacement transmission mechanism 15 are moved so that the inner peripheral head 3a moves to the (n + 1) th track immediately inside the nth track. Operate. When the head 3 is moved, the connection of the switching circuit 4 and the operation of the recording / amplifying circuit 11 are switched again in the same manner as in the case of erasing the field recording track, and the erase signal amplified by the inner peripheral head 3a is output. The data is supplied and the (n + 1) th track is erased. As a result, both the n-th track and the (n + 1) -th track, which are a pair of tracks constituting the frame image, are erased, and then the control circuit 9 returns to the standby state.

As a third case, consider a case where the n-th track is the inner track of the frame recording tracks. In this case, the n-th track itself is erased in exactly the same manner as in the first case for the field recording track. Next, the head is not moved by the position control signal PC, and the connection is switched in the switching circuit 4 by the timing signal T1. That is, in the switching circuit 4, the connection between the first terminal 4a and the fourth terminal 4d at the time of the n-th track erasure is released, and the second terminal 4b and the fourth terminal 4d are connected instead. On the other hand, since the recording / amplifying circuit 11 operates to amplify and output the erase signal by the timing signal T2, the amplified erase signal is supplied to the outer head 3b. Therefore, the (n-1) th track immediately outside the nth track is erased by the outer circumference head b. That is, both the n-th track and the n-th track, which are a pair of tracks forming the frame image, are erased. Thereafter, the control circuit 9 returns to the standby state.

If the erasing signal generating circuit 16 and the recording / amplifying circuit 11 are of sufficient capacity, the first terminal 4a and the second terminal 4b of the switching circuit 4 are connected in accordance with the third case. Both are connected to the fourth terminal 4d, so that an erasing signal is simultaneously supplied to both the outer head 3b and the inner head 3a, so that the (n-1) th track and the nth track constituting a frame image are simultaneously Of course, it may be configured to erase.

Various modifications and changes can be made to the above-described erase control operation and the like within the scope of the present invention. That is, for the floppy disk 1 mounted on the apparatus, all the tracks are scanned by the head 3 in advance, and the ID of each track is
The signal is decoded, and the result is even stored in a memory in the control circuit 9. When an erasure track number is designated by a command signal from the terminal 12, the erasure operation may be performed by identifying the field / frame storage mode on the basis of the above-mentioned stored contents. In this case, the two-channel head 3 can always access the pair of frame recording tracks with one behavior and simultaneously erase the two tracks. In the example shown in FIG. 2, an in-line two-channel type head is used as the head 3 and both channels are used for recording, reproducing and erasing operations. However, a single head is used instead of such a head. Apply or record
It is also possible to provide a configuration in which an erasing head is provided in addition to the re-head. In these cases, head access to the track on the second erased side of the pair of tracks for frame recording is indispensable, but otherwise the operation is substantially the same as the above-described operation in the example of FIG. Becomes

Among the various aspects described above, there are the following problems when an erasing operation is performed by a head that is not dedicated to erasing. In other words, when erasing is performed by a head having the same width as the head used for recording, the eccentricity when the floppy disk 1 is mounted, the expansion and contraction or deformation of the floppy disk 1 itself, or the tolerance of the head position control, etc. There is a possibility that partial unerased parts may occur. In order to solve this problem, a technique is known in which the head is moved in the width direction of the track to be erased and the erasing operation is performed by rotating the floppy disk two or more times so that the unerased portion is eliminated as described above. It is. When the head is moved in the width direction of the track for the above purpose, the track pitch (the distance between the centers of adjacent tracks) is very small, so that the data is erased even to the adjacent track not to be erased. In order to avoid this, it is desirable that the size is minute. On the other hand, if such a small displacement is enabled, a new problem arises in that high-speed head access becomes difficult. Generally, in order to obtain a relatively long feed operation such as movement between tracks in a secondary mechanism (consequently) with a high-resolution feed mechanism capable of minute displacement, a very multi-stage or extremely high-speed temporary drive (for example, a motor) This is because rotation driving by a driving source is required.

In the device of the present invention, in order to solve such a problem, an extremely characteristic mechanism as described in detail below is applied as the displacement transmission mechanism 15.

FIG. 3A shows the displacement transmission mechanism 15 of the device shown in FIG.
FIG. 3 is a diagram specifically showing the mechanism of FIG. Fig. 3 (a)
The head 3 includes an inner head 3a and an outer head 3b
Is an in-line two-channel type.
The head 3 is mounted on a head carriage 20 movably provided while being guided by a pair of guide rods 21a and 21b. A cam 41 as a displacement conversion element is provided so as to be rotationally driven by a stepping motor 30 (in which a stepping motor is applied as the motor 14 in FIG. 2).
A displacement conversion mechanism 40 is formed together with a roller-shaped cam follower 42 provided on 20. Above both guide rods 21a, 21
As for b, each right end in the figure is fitted and fixed to the structural member 50 of the present apparatus. Although not shown, each left end is similarly fixed. The two guide rods 21a and 21b penetrate through insertion holes provided in the head carriage 20, and guide and support the head carriage 20 movably. Between the right side surface of the head carriage 20 in the drawing and the left side surface of the structural member 50 facing the head carriage 20, the compressible coil springs 22a are formed substantially along the outer peripheries of the guide rods 21a, 21b.
22b is provided so that a biasing force toward the cam 41 is constantly applied to the head carriage 20. Therefore, the cam follower 42 provided on the carriage 20 is always in elastic contact with the cam 41. Further, a still video floppy disk 1 rotated and driven by a spindle motor (not shown) is arranged as shown by a two-dot chain line, and the above-mentioned head is placed on the annular information recording tracks 2a and 2b formed on the floppy disk 1. 3a and 3b are configured to trace.

The cam 41 as the conversion element has a characteristic pattern as shown in FIG. 3B in which a part b of the peripheral surface is enlarged. That is, in the cam 41, the distance r from the center of rotation O to a portion P where the peripheral surface of the 41 and the peripheral surface of the cam follower 42 contact each other has a displacement of zero or a small displacement according to the clockwise rotation angle of the cam 41. The pattern is made up of a combination of a region and a region where displacement increases. The characteristics of the cam 41 will be more clearly understood from the characteristic diagram shown in FIG.

In FIG. 4, the horizontal axis represents the rotation angle of the stepping motor 30 by the number of steps, and the vertical axis represents the displacement of the head (this corresponds to the aforementioned distance r) by the track number on the medium. For the vertical axis, for example,
The distance from a track to the next n + 1 track, that is, the interval between adjacent tracks is the so-called track pitch. In the case of an electronic still camera, this is 100
μm.

The operation of the displacement transmission mechanism 15 configured as described above will be described below. The inner peripheral head 3a of the head 3 is a floppy disk 1
It is assumed that the rotation position of the cam 41 when the normal position of the n-th track is traced is the rotation reference position, that is, the position where the number of steps is zero in FIG. In order to properly trace the n-th track of the rotating floppy disk 1 while the head 3a is actually rotating, the position tolerance of the recording device when recording the same track, and the rotational driving of the floppy disk 1 during reproducing / erasing are required. The head is moved in the width direction of the track at the time of erasing in response to the dynamic displacement of the track from its normal position due to the influence of eccentricity and displacement of the floppy disk 1 over a plurality of rotations of the floppy disk 1. Perform an erase operation,
At the time of reproduction, tracking control for dynamically following the actual position of a track by dynamically displacing the head is required.

In this example, an example in which an erase operation is performed on the n-th track will be described. First, based on the n-th track erasing instruction, the stepping motor 30 moves the cam 41 one rotation step outward from the position of the stagnation characteristic portion B where the head 3a traces the rotation reference position under the above assumption, that is, the normal position of the n-th track. It rotates to the position indicated by A in the feed characteristic portion (the position where the number of steps is -1 in FIG. 4). At this position, an erasing current is supplied to the head 3a, and the floppy disk 1 is driven by one rotation so that the entire circumference of the annular portion including the outer peripheral edge of the n-th track is erased. Next, the cam 41 is rotated to the rotation reference position (the position where the number of steps is zero in FIG. 4) corresponding to the n-th track, and the head 3a moves to the reference position of the n-th track at the position of the stagnation characteristic portion B. The entire circumference is erased. Further, the cam 41 is turned to the position indicated by C (the position where the number of steps is 1 in FIG. 4) in the feed characteristic portion on the inner peripheral side of one step from the position corresponding to the n-th track. At this position, the entire periphery of the annular portion including the inner periphery of the n-th track is erased as described above. When the control circuit 9 detects that the track of the actual recording track deviates from the track of the regular track by the reproduction output, if the control circuit 9 deviates inward from the regular track, it turns. Reference position,
The full circumference operation is performed in the same manner as described above on each of the inner circumferential side of one step of the rotation reference position and the inner circumference of two steps of the rotation reference position. If the deviation is out of the normal track, the rotation reference position, the outer peripheral side of one step of the rotational reference position, and the outer peripheral side of the two steps of the rotational reference position are similarly set as described above. To perform the full circumference operation.
Needless to say, each stepping operation of the cam 41 and thus the head 3a is performed based on the position control signal PC from the control circuit 9 in FIG. In the apparatus of this example, the erasing operation is performed as described above. Therefore, when erasing the n-th track, the entire area is erased from the reference position of the track to the annular area whose width is increased toward the outer circumference and the inner circumference. Is made. Therefore, there is no possibility that the left and right edges of the track are left unerased. In the above description, the erasing area for erasing is set to ± 1 step at a time, but may be arbitrarily set to ± 2 steps at a time so as to surely remove the erasing residue. . In addition, the order of erasing is, of course, from the outer circumference to the inner circumference, and may be variously selected.

Next, operations at the time of reproduction and at the time of head access will be described. In this example, in order to perform tracking control on n tracks, the drive pulse is, for example, one step in the forward rotation direction from the motor drive circuit 13 in FIG. 1) or to provide a rotation angle of one step (-1 on the horizontal axis in FIG. 4) in the reverse direction, whereby tracking is performed to the area A or C in the feed characteristic portion of the cam 41. And fine tracking control can be properly performed. This tracking will be described in more detail. The control circuit 9 decodes the ID signal from the reproduction lead by the inner head 3a via the data demodulation circuit 8 and, if the n-th track is field recording, without further head access (fine tracking control). Is performed), and the image reproducing operation is repeated by the inner peripheral head 3a. At this time, if a monitor is connected to the video output terminal 7, the field image (still image) of the n-th track is continuously observed. When it is detected from the contents of the ID signal that the n-th track is the inner track of the frame recording tracks, the switching of the switching circuit 4 is performed without further head access (however, fine tracking control is performed). The reproduction of the outer peripheral head 3b and the inner peripheral head 3a is performed. When it is detected from the contents of the ID signal that the n-th track is the outer track of the frame recording tracks, head access is performed, and the correspondence between the head 3 (3a, 3b) and the track (inner, outer) is determined. The same operation as described above is performed, and then the image reproducing operation is repeated. At this time, a frame image (still image) is displayed on the monitor
Are continuously observed.

On the other hand, when the head 3 is made to access the head from the n-th track to the next (n + 1) -th track, the steep slope provided corresponding to the rotation angle of the pulse motor 30 and therefore the cam 41 between the first to seventh steps. The steep displacement is given to the head 3 by the action of the feed characteristic portion D, and the head 3 moves quickly from the n-th track position to the (n + 1) -th track position. Of course, the tracking control for the (n + 1) th track is performed in the same manner as performed for the nth track. The head access to the (n + 2) th track and the (n + 3) th track and the tracking control for each of those tracks are performed in the same manner as described above.

In the cam 41 as the above-described displacement conversion element, in other words, the fine displacement area is set at the normal position of each track (the fourth position).
A stagnation characteristic portion B is provided around the position of the step number 0, 8...), And a steep displacement region is provided as a feed characteristic portion D between the stagnation characteristic portions B. I can say. As described above, in the present example, the stagnation characteristic portion B (flat portion), which is a dead band, and the feed characteristic portion D formed of a steeply inclined portion connected thereto are formed. Even if the pulsation component is included in the rotation of the motor 30 (that is, the cam 41), the influence can be suppressed to a minimum, and the operation of the tracking units A and C in the feed characteristic unit D is smooth and stable. Tracking control is realized. In this respect, a step-like fine pitch feed portion V and a rough pitch feed portion W as shown in FIG.
It can be said that tracking smoothness is superior to the combination of the above. The effect of quick head access by the feed characteristic portion D which is a steeply inclined portion is obtained by comparing the characteristics of FIG. 6 with the characteristics of FIG. 4 by a general cam formed only by the fine pitch feed portion. You can clearly see how remarkable it is.

The mechanism of the present embodiment can be variously modified and changed in addition to the above. For example, instead of using the cam 41 and the cam follower 42 as shown in FIG. 3A as the displacement conversion mechanism 40, a groove cam 41 'having a spiral groove as shown in FIG. Pin-shaped cam follower 4
2 'may be applied. The groove cam 41 'as a displacement conversion element shown in FIG.
In place of the cam 41, is mounted in exactly the same way,
It is configured to be rotationally driven by the pulse motor 30. Correspondingly, a pin-shaped cam follower 42 'is also provided at a position corresponding to the cam follower 42 on the head carriage 20 in FIG. 3 (a). In this case, the cam follower
It goes without saying that the positional relationship between the groove cam 41 'and the cam follower 42' should be adjusted so that the tip of the groove 42 'can properly trace the groove on the groove cam 41'. In the groove cam 41 'as the displacement conversion element in FIG. 7, the relationship between the distance from the center of rotation to the portion where the cam follower 42' fits into and slides into the cam groove, and the rotation angle with the cam 41 ', The cam groove is configured to include a stagnation characteristic portion B and a feed characteristic portion D, just like the one shown in FIG. Therefore, in the device of the present invention, the displacement conversion mechanism
When the element shown in FIG. 7 is used as 40, the operation and effect exactly the same as those described with reference to FIGS. 3 and 4 are achieved. In particular, if an element as shown in FIG. 7 is applied as the displacement conversion mechanism 40, by appropriately selecting the shape and size of the groove, the structure shown in FIG.
It is possible to adopt a configuration in which the urging means 22a and 22b are not necessarily required.

FIG. 8 is a view showing another example of the displacement conversion mechanism in the device of the present invention. In FIG. 8, parts corresponding to those in FIG. 3 (a) are denoted by the same reference numerals. The head carriage 20 to which the head 3 is attached has structural members at both ends.
The guide rods 21 are fixed to the guide rods 21 so as to slide. One end of a cam follower member 42 'made of an elastic body is fixed to an appropriate position of the head carriage 20, and a cam follower piece 420 is provided at the other end. The cam follower piece 420 is designed to be preloaded and fitted into a cam groove of a substantially helical groove cam 41 ′ engraved on a predetermined surface of a cylindrical shaft 430. The shaft 430 is configured so that its movement in the thrust direction is regulated by bearings 440 and 450, and is rotated by the driving force of the motor 30 given through the bevel gear 60. Groove cam 41 'and cam follower piece 42
0 (cam follower member 42 ') forms the displacement conversion element of the present invention. Groove cam 41 'and therefore rotation angle of shaft 430 (number of rotation steps of motor 30) and cam follower piece
420 displacement (ie, displacement of the head 3 moved via the cam follower member 42 'and the head carriage 20)
The groove cam 41 'and the cam follower piece 420 are formed so that the displacement conversion characteristics between the groove cam 41' and the cam follower piece 420 are exactly the same as those shown in FIG. Therefore, even if the displacement conversion mechanism in the device of the present invention is configured as shown in FIG. 8, the same operation and effect as those described with reference to FIGS. 3 and 4 can be obtained. Further, according to the configuration of FIG. 8, as in the case of the example of FIG. 7, the configuration in which the urging means 22a and 22b as shown in FIG.

FIG. 10 to FIG. 12 are flowcharts showing the flow of the operation of the present apparatus. This will be described below.

It is determined whether or not the recording medium is mounted, and if it is mounted, a preliminary reproduction operation is performed for all tracks (detection of a reproduction envelope level at a regular position of each track. A reproduction envelope level one step outer circumference from the regular position of each track) Detection: Detection of the playback envelope level at the inner circumference of one step from the normal position of each track, decoding of the ID signal,
Identification of frame / field records. ).
The result obtained by this preliminary reproduction operation is stored in the RAM. Next, the operation mode changeover switch is read, and when the switch is in the "erase mode", the erase mode is entered, and the track on which the erase designated image is recorded is read. Subsequently, the state of the erase start button is determined, and if the above button is ON, the erase is started. This erase start button is for preventing erroneous erasure. The flow of the erase operation is shown in FIG. First, the state of the track deviation is determined from the RAM storing the result of the above-mentioned preliminary reproduction operation. Here, when it is determined that the track is at the regular position, the erase operation is executed for the regular position of the track and the position of ± 1 step from the regular position. If it is determined that the track is shifted inward from the regular position, the erase operation is performed for the regular position of the track and at positions ± 1 and ± 2 steps from the regular position. When it is determined that the track is shifted to the outer peripheral side from the regular position, the erasing operation is performed on the regular position of the track and the position of -1 and -2 steps from the regular position. After rewriting the RAM information on the erased track after executing each erase operation,
The operation mode changeover switch in the figure returns to the reading state.

When reading the state of the operation mode changeover switch, if the operation mode changeover switch is set to the "playback mode", the operation mode is changed to the reproduction mode, and the track on which the reproduction designated image is recorded is read, and the track read here is read. Play image information. FIG. 12 shows the flow of the reproducing operation. As in the case of erasing, the state of the track shift is determined from the information in the RAM. As a result of this determination, when it is determined that the track is at the regular position, the reproduction is executed with the head position at the regular position of the track. When it is determined that the track is shifted inward from the normal position, reproduction is executed at the head position one step inward from the normal position of the track. When it is determined that the track is shifted to the outer peripheral side from the regular position, the reproduction is executed at the head position one step outer peripheral side than the regular position of the track. After completion of each reproduction, the operation mode changeover switch in FIG. 10 returns to the reading state. As described above, even if the actual position of the track is deviated from the normal position, the tracking control for adjusting the head position to the actual position of the track is performed, and the reproducing operation is performed in an optimal state.

Operation mode changeover switch Reading result is "Recording mode"
If so, the recording mode is set and the state of the recording start button is determined. If the recording start button is ON, recording is performed. This recording start button prevents post-recording like the erase start button.

〔The invention's effect〕

According to the present invention, the primary displacement, which is input from the drive source, is converted into a secondary displacement, which is an output to be given to the head carriage, and the secondary displacement is zero or a small amount with respect to a predetermined amount of the primary displacement. A displacement conversion element configured to exhibit a displacement conversion characteristic including a plurality of stagnation characteristic portions and a feed characteristic portion that obtains a secondary displacement larger than the stagnation characteristic portion for a predetermined amount of the primary displacement is used. Therefore, an information erasing / reproducing apparatus capable of displacing the head in minute units without sacrificing the head access speed and performing an erasing operation with no erasure and accurate and fine tracking control is provided. can do.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of the present invention, FIG. 2 is a block diagram showing an electric circuit section of an apparatus as one embodiment of the present invention, FIG.
2A is a diagram showing a mechanism of a displacement transmission mechanism of the apparatus shown in FIG. 2, FIG. 3B is an enlarged view of a main part of the mechanism shown in FIG. 3A, and FIG. 4 is a diagram shown in FIG. FIGS. 5 and 6 show the characteristics of a device having no features as shown in FIG. 4, and FIG. 7 shows a modification of the mechanism of FIG. 3 (a). FIG. 8 is a diagram showing another example of the displacement transmitting mechanism in the apparatus of the present invention. FIG. 9 is a diagram showing allocation of data information recording areas on tracks of a floppy disk in the standard of an electronic still camera. 10 ~
FIG. 12 is a flowchart showing the flow of the operation of the present apparatus. 100: medium, 200: head, 300: head carriage, 400: drive source, 500: displacement conversion element, 600
... Control means, 700 ... Motor, A, C ... Tracking section, B ... Stagnation characteristic section, D ... Feeding characteristic section.

Claims (1)

(57) [Claims] 1. A head adapted to function as at least an erasing head or a reproducing head with respect to a recording track of a recording medium, a head carriage provided to be displaceable while supporting said head, and a head carriage being displaced. A driving source for generating a driving force for providing the head carriage, and converting the primary displacement as an input transmitted by the driving source into a secondary displacement as an output to be applied to the head carriage with respect to a predetermined amount of the primary displacement. It is configured to exhibit a displacement conversion characteristic including a plurality of stagnation characteristic portions in which the next displacement is zero or a small amount and a feed characteristic portion that obtains a secondary displacement larger than the stagnation characteristic portion for a predetermined amount of the primary displacement. And the stagnation characteristic section corresponding to the track to be erased or reproduced at least in the erasing or reproducing operation mode. Displacing the head in an area on the recording medium corresponding to a section including at least a part of the feed characteristic section connected to the characteristic section, and performing an erasing operation on the head in this area, or within this area. A recording information erasing / reproducing apparatus, comprising: control means for performing a reproducing operation with tracking control for selecting a head position.