JP2998261B2 - Signal recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal recording / reproducing apparatus suitable for application to, for example, a video tape recorder.

[0002]

2. Description of the Related Art Tape guides used in signal recording / reproducing devices such as video tape recorders are roughly classified into rotary guides and fixed guides. The rotary type is characterized in that the running resistance applied to the tape is small. However, for example, if the rotation unevenness of the bearing used appears as tape running unevenness or if the running direction of the tape is not perpendicular to the rotating direction of the rotating roller, the tape exerts a force in the width direction from the roller. There were drawbacks such as receiving. In particular, in the latter case, the tape may move in the width direction and damage the edge of the tape. Therefore, when a rotary type tape guide is used, the precision of parts and the precision of assembly must be made extremely high, which makes the production difficult. On the other hand, the fixed type has a stable running of the tape, but has a disadvantage that the running resistance of the tape is large. For these reasons,
There is a demand for a tape guide that is a fixed type and has a small running resistance of the tape. An example is an air guide. This air guide is of a system in which air is blown out from a small hole provided on the surface of the guide body to float the tape and reduce the running resistance of the tape. However, even with this air guide, new problems arise, such as the need for a compressor as an air source. In order to solve such drawbacks and problems, the present applicant has previously disclosed an ultrasonic vibration tape guide device using ultrasonic waves (Japanese Patent Application No. 02-103627).
Has been proposed. In the ultrasonic vibration tape guide device, the running resistance of the tape can be reduced while maintaining the stability of the running of the fixed tape.
The height of the ultrasonic vibration tape guide device can be adjusted. Hereinafter, the ultrasonic vibration tape guide device will be described with reference to FIG.

In FIG. 22, reference numeral 5 denotes a main shaft erected on the base 18. The guide member 2 to which the ultrasonic transducer 3 is fixed is supported by a cylindrical brass support shaft 7 having a support protrusion 7b. The ultrasonic vibrator 3 has a positive electrode and a negative electrode electrically connected to a positive electrode plate having a positive electrode disposed on one surface and a negative electrode disposed on the other surface between a number of piezoelectric ceramic plates. An insulating member is attached to one end face of a piezoelectric ceramic element which is electrically connected to the negative electrode plate and arranged alternately, and a fixing surface is formed on the other end face of the piezoelectric ceramic element. A positive electrode lead 3a is connected to a positive electrode plate of the ultrasonic vibrator 3, and a negative electrode lead 3b is connected to a negative electrode plate of the ultrasonic vibrator 3. The fixed surface of the ultrasonic vibrator 3 is a curved surface formed at one end of the piezoelectric ceramic element corresponding to the diameter of the guide member 2, and the fixed surface contacts and adheres to the outer peripheral surface of the guide member 2.

The lower and upper flanges 9 and 10 are arranged so as to contact the upper and lower ends of the support shaft 7, and serve to guide the edge of the tape wound around the guide member 2. The main shaft 5 is configured to pass through the lower and upper flanges 9 and 10 and the support shaft 7. 6
Reference numeral denotes a height adjusting screw fitted to the inner periphery of the upper end of the support shaft 7 and screwed to a screw 23 formed at the end of the main shaft 5. Reference numeral 8 denotes a mounting member, on which an upper flange 10 is fixed with mounting screws 15,
A lower flange 9 is provided at a lower portion of the mounting member 8 with the fixing pin 2.
2 and 24 are fixed. As shown in FIG.
The element accommodating portion 8a of the mounting member 8 is formed by forming a rectangular parallelepiped hole leaving side walls 8b on both sides, and stopper fitting holes 8c are formed on both side walls 8b.

A locking projection 39a of a disc-shaped stopper 39 made of rubber is fitted into the stopper fitting hole 8c.
The rotation of the guide member 2 is prevented by sandwiching the ultrasonic vibrator 3 by the stopper 39. The mounting member 8 serves to keep the lower and upper flanges 9 and 10 parallel and to keep their spacing about 0.1 mm larger than the length of the guide member 2. As shown in FIG. 22, the lower flange 9 is pushed upward by the biasing force of a coil spring 35 disposed on the outer periphery of the main shaft 5 between the lower flange 9 and the base 18. A pin insertion hole 20 is formed in the base 18, and the insertion hole 20 has a lower flange 9.
A fixing pin 22 planted on the lower surface is inserted. In such a configuration, when the height adjustment screw 6 is rotated,
The height of the guide member 2 can be adjusted by the biasing force of the coil spring 35 and by using the biasing force. FIG. 24 shows a state in which an AC voltage is applied to the ultrasonic vibrator 3 and the state of the standing wave vibration generated in the guide member 2 is cut along line XX and developed. As shown in FIG. 24, a dotted line N-N is a node portion, on which amplitude is zero. Assuming that the distance from the end face of the guide member 2 to the position of the node is n, the axial position of the support protrusion 7b is provided at a distance of n from the end face of the guide member 2.

FIG. 25 shows a state in which a tape cassette 41 is mounted on a tape guide device 64 of a video tape recorder in which the above-described ultrasonic vibration tape guide device 1 is mounted. In FIG. 25, reference numeral 40 denotes a base of the tape guide device 64, and reference numerals 42 and 43 denote S (supply) and T (rewind) reels (hereinafter, referred to as S reel and T reel, respectively), 44, 45, 48, 49 and 5
Numeral 0 is a guide arranged at a predetermined position, 46 is a capstan, 47 is a recording / reproducing head for, for example, an audio signal, and 51 is an erasing head.

Reference numeral 41a denotes a concave portion provided in the cassette 41. Guides 57 and 58 are provided inside the tape cassette 41. The guides 57 and 58 guide the tape 59 so as to cover the front surface of the concave portion 41a of the tape cassette 41. The ultrasonic vibration tape guide device 1, the pinch roller 65, and the slider guides 60 and 61 are disposed inside the concave portion 41a covered by the tape 59.

[0008] Stoppers 53 and 54 are slider guides 60 and 61, respectively.
Are provided for performing positioning with respect to the rotary head 52, respectively. 55 and 56 are connector portions attached to stoppers 53 and 54, respectively.
5 and 56 have terminal pins 55a and 56a, respectively, and are provided for supplying an AC voltage from the video tape recorder main body 70 to the slider guides 60 and 61, respectively.

FIG. 26 shows a state in which the tape 59 is pulled out of the tape cassette 41 from the state shown in FIG. 25, is wound around the rotary head 52, and is capable of recording and reproduction. That is, in FIG. 26, FIG.
In the state (1), the slider guides 60 and 61, the ultrasonic vibration tape guide device 1, and the pinch roller 65 are respectively moved to predetermined positions, and the tape 59 is wound around the rotary head 52 (loading state). Is shown. In this case, the slider guides 60 and 61 are provided with positioning pins 60a and 6 provided respectively.
V-shaped portions 5a provided on stoppers 53 and 54, respectively.
It is configured to be positioned in contact with 3a and 54a. The ultrasonic vibration tape guide device 1 moves to the position shown in FIG. 26, and the pinch roller 65 moves to a position facing the capstan 46. In this state, the tape guide device 64 is in a state where recording and reproduction are possible.

[0010]

The effect of reducing the coefficient of friction in the ultrasonic vibration type tape guide device 1 described above has a characteristic that varies depending on the speed of the tape 59. In FIG. 27, the vertical axis indicates the friction coefficient (μ) and the horizontal axis indicates the speed (× 100 mm / s), and the tape guide device 1
Input to the ultrasonic vibrator 3 of 0 (W) to 0.6
A graph shows the relationship between the tape speed and the coefficient of friction when changing to (W). As is clear from FIG.
In a low speed region, for example, 10 mm / sec or less, a large effect of lowering the friction coefficient can be obtained with a small electric power. In a high speed region, for example, 500 mm / sec or more, the entrainment of air causes the guide member 2 by the ultrasonic vibrator 3. The coefficient of friction is low irrespective of the presence or absence of vibration. However,
Conventionally, in spite of the fact that the friction coefficient changes in relation to the speed of the tape 59, the power supplied to the ultrasonic vibrator 3 of the tape guide device 1 is changed correspondingly. I didn't. In addition, a signal recording / reproducing apparatus such as a video tape recorder has various modes such as variable speed reproduction, fast forward, and rewind in addition to a normal running mode. The power supplied to the first ultrasonic transducer 3 was not changed. Further, in the case of the fast-forward mode, for example, increasing the tape speed at a high acceleration leads to a reduction in the feeding time. However, the higher the acceleration, the lower the speed range, that is, 500 mm / mm shown in FIG.
The tension applied to the tape 59 by the frictional force in seconds or less increases. This tension can be reduced by adopting the ultrasonic vibration type tape guide device. However, in the high speed region, the friction coefficient becomes low as described above, and the ultrasonic vibration type tape guide device is used. Is less needed. That is, by controlling the voltage input to the ultrasonic vibrator 3 on the time axis, the device can be operated efficiently. However, conventionally, input voltage control on the time axis in such a single mode has not been performed. Therefore, there has been a disadvantage that the tension of the tape cannot be optimized, and efficient operation of the apparatus cannot be realized in terms of power reduction.

The present invention has been made in view of the above points, and a signal recording / reproducing apparatus capable of optimizing the tension of a tape and realizing efficient operation of the apparatus in terms of power reduction. It is intended to propose.

[0012]

The signal recording / reproducing apparatus of the present invention is constructed such that the speed of the tape 59 is controlled in accordance with the operation mode as shown in FIGS. A signal recording / reproducing apparatus which records and / or reproduces a signal on / from a tape 59 by using an ultrasonic vibration type tape guide 200 as a tape guide member for guiding, based on an operation mode and a tape speed. Control means 100, 109 and 50 for variably controlling the vibration amount of the ultrasonic vibration type tape guide 200
0 is provided.

[0013]

According to the present invention described above, the control means 100, 1
09 and 500 variably control the vibration amount of the ultrasonic vibration type tape guide 200 based on the operation mode and the tape speed, so that the tension of the tape can be optimized and the power consumption can be reduced. In this case, efficient operation of the apparatus can be realized.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the signal recording / reproducing apparatus according to the present invention will be described below in detail with reference to FIGS. First, the essential parts of the signal recording / reproducing apparatus of the present invention will be described with reference to FIG. In FIG. 3, reference numeral 52 denotes a rotary head,
115s is a movable guide on the supply reel (not shown) side, 114s is a tape guide on the supply reel side, 115t
Denotes a movable guide on a take-up reel (not shown) side;
14t is a tape guide on the take-up reel side, and a tape 59
However, these movable guide 115s, tape guide 114
s, the rotating head 52, the movable guide 115t, and the tape guide 114t to form a rotating head 5 at a predetermined winding angle.
It is wound around 2 and guided. 113s and 113t
Are ultrasonic vibrators, and one end surfaces of these ultrasonic vibrators 113s and 113t are respectively adhered to the tape guides 114s and 114t, for example, respectively.
The tape guide device main body 200 is composed of the tape guide 114s, the ultrasonic transducer 113t, and the tape guide 114t.

Reference numeral 100 denotes a control unit.
PU 102, bus 103 (consisting of data, address and control bus), ROM 104, RAM 105,
System controller 106, AD converter (analog-digital conversion circuit), and DA converter 10
8. Reference numeral 109 denotes a driving unit.
To the temperature compensation circuits 111 s and 111 t and the drive circuit 112.
s, 112t. The temperature compensation circuit 111s
Bus 103 and DA converter 108 from PU 102
The control signal is added to the offset signal and the control signal supplied via the control circuit 112, and the added signal is supplied to the drive circuit 112s. The drive circuit 112s oscillates a signal based on the added signal supplied from the temperature compensation circuit 111s, and changes the gain for the oscillated signal based on gain data supplied from the CPU 102 via the bus 103, and changes the gain. The signal is supplied as a drive signal to the tape guide device main body 200 including the ultrasonic vibrator 113s and the tape guide 114t. The temperature compensation circuit 111t
The offset signal and the control signal supplied from the U102 via the bus 103 and the DA converter 108 are added, and the added signal is supplied to the drive circuit 112t. The drive circuit 112t oscillates a signal according to the added signal supplied from the temperature compensation circuit 111t, and changes the gain for the oscillated signal based on gain data supplied from the CPU 102 via the bus 103, and changes the gain. The signal is supplied as a drive signal to the tape guide device main body 200 including the ultrasonic vibrator 113t and the tape guide 114t.

Reference numeral 116s denotes a magnetic sensing portion.
Is attached to the movable guide 115s. This magnetic sensing part 116
s is the movable guide 115s by the tension of the tape 59
Is detected, and the detected signal is supplied to the tension detection circuit 117s. The tension detection circuit 117s detects the tension of the tape 59 based on a detection signal from the magnetic sensing unit 116s, and supplies the detection signal to the CPU 102 via the A / D converter 107 and the bus 103. Reference numeral 116t denotes a magnetic sensing portion, which is attached to the movable guide 115t. This magnetic sensing part 116t
Detects the amount of movement of the movable guide 115t due to the tension of the tape 59, and supplies the detected signal to the tension detection circuit 117t. This tension detection circuit 1
17s detects the tension of the tape 59 based on the detection signal from the magnetic sensing unit 116s, and supplies this detection signal to the CPU 102 via the A / D converter 107 and the bus 103.

Reference numeral 118s denotes a peak hold circuit. The peak hold circuit 118s drives a tape guide device main body 200 on a supply reel (not shown) side and generates a substantially DC current signal from a drive signal from the drive circuit 112s. Then, the current signal is supplied to the A / D converter 107 and the bus 1
03 to the CPU 102. This current signal is used in power control described later. 119s is a peak hold circuit, and this peak hold circuit 119s is
A substantially DC voltage signal is obtained from a drive signal from the drive circuit 112s for driving the tape guide device main body 200 on the supply reel (not shown) side, and this voltage signal is converted via the AD converter 107 and the bus 103. It is supplied to the CPU 102. This voltage signal is used in power control and temperature compensation described later. 119s is a phase detection circuit. The phase detection circuit 119s obtains a voltage signal and a current signal from a sine wave drive signal from the drive circuit 112s, further obtains a rectangular wave signal from the voltage and current signal, respectively. Is detected, that is, the phase shift between the voltage and the current is detected, and this detection signal is sent to the A / D converter 107 and the bus 1.
03 to the CPU 102. Reference numeral 121s denotes a distortion detection circuit.
A voltage signal is obtained from the sine-wave drive signal from s, a harmonic component is further extracted from the voltage signal, a substantially DC voltage signal is obtained from the harmonic component, and this voltage signal is converted into an A-D converter 107 and a bus. The data is supplied to the CPU 102 via the communication terminal 103.

Reference numeral 118t denotes a peak hold circuit which drives the tape guide device main body 200 on the take-up reel (not shown) side.
A substantially DC current signal is obtained from the drive signal from the drive circuit 112t, and this current signal is supplied to the CPU 102 via the A / D converter 107 and the bus 103. This current signal is used in power control described later. 119t is a peak hold circuit.
Obtains a substantially DC voltage signal from a drive signal from a drive circuit 112t that drives the tape guide device main body 200 on the take-up reel (not shown) side, and converts this voltage signal to A-
CPU 10 via D converter 107 and bus 103
Feed to 2. This voltage signal is used in power control and temperature compensation described later. 119t is a phase detection circuit. The phase detection circuit 119t obtains a voltage signal and a current signal from the sine wave drive signal from the drive circuit 112t, further obtains a rectangular wave signal from the voltage and current signal, respectively. , That is, the phase shift between the voltage and the current is detected, and this detection signal is supplied to the CPU 102 via the A / D converter 107 and the bus 103. Reference numeral 121t denotes a distortion detection circuit.
A voltage signal is obtained from a sine wave drive signal from 12t, a harmonic component is further extracted from the voltage signal, a substantially DC voltage signal is obtained from the harmonic component, and this voltage signal is converted into an A-D converter 107 and a bus. The data is supplied to the CPU 102 via the communication terminal 103.

The above-described tape guide device main body 200 has a configuration as shown in FIGS. 6 and 7, respectively. Note that FIG.
The structure and the like of the tape guide device main body 200 shown in FIG. 7 and FIG. 7 are the same as those of the tape guide device 1 described in FIG. 22 and FIG. The ultrasonic vibrator 3 in FIG. 6 is the same as the ultrasonic vibrators 113s and 113s described above.
13t. 1 and 2 show an embodiment in which the signal recording / reproducing apparatus of the present invention is applied to a video tape recorder. In FIG. 1, portions corresponding to those in FIG. 25 are denoted by the same reference numerals, and detailed description thereof will be omitted. This FIG.
A state where the tape cassette 41 is placed on the tape guide device 64 of the video tape recorder is shown. In FIG. 1, reference numeral 40 denotes a base of the tape guiding device 64;
Reference numerals 2 and 43 denote S (supply) and T (rewind) reels (hereinafter referred to as S reels and T reels, respectively), and 44, 45, 48, 49, and 50 guides disposed at predetermined positions, respectively. , 46 are capstans, 47 is a recording / reproducing head for, for example, an audio signal or the like, and 51 is an erasing head.

Reference numeral 41a denotes a recess provided in the cassette 41. Guides 57 and 58 are provided inside the tape cassette 41. The guides 57 and 58 guide the tape 59 so as to cover the front surface of the concave portion 41a of the tape cassette 41. The tape guide device main body 200, the pinch roller 65, the slider guide 6 are provided inside the concave portion 41 a covered with the tape 59.
0 and 61 are provided respectively. 53 and 54 are stoppers, respectively. The stoppers 53 and 54 are provided for positioning the slider guides 60 and 61 with respect to the rotary head 52, respectively. 55 and 56 are connector portions attached to stoppers 53 and 54, respectively. The connector portions 55 and 56 are terminal pins 55a, respectively.
And 56a, and are provided for supplying an AC voltage from the video tape recorder main body 300 to the slider guides 60 and 61, respectively. Also, the video tape recorder 300 processes the control unit 100, the driving unit 109, the detection unit 500, the reproduction signal and the recording signal described in FIG. 3, and performs the signal processing and control by operating various operation switches and the like. It is composed of a signal processing unit 600 for performing the operation, various drive mechanisms not shown, and the like. As shown in FIG. 1 and FIG. 2 described below, the angle detectors 116s and 116t are, for example, movable guides 115s and 1t, respectively.
15t.

FIG. 2 shows that the tape 59 is pulled out of the tape cassette 41 from the state shown in FIG.
2 shows a state in which recording and reproduction are enabled. That is, in FIG. 2, in the state of FIG. 1, the slider guides 60 and 61, the tape guide device main body 200, and the pinch roller 65 are respectively moved to predetermined positions.
Reference numeral 9 denotes a wound state (loading state). In this case, the slider guides 60 and 61 are respectively provided with V-shaped portions 53a and 54 provided on the stoppers 53 and 54 by positioning pins 60a and 61a provided respectively.
a. The tape guide device main body 200 moves to the position shown in FIG. 2 and the pinch roller 65 moves to a position facing the capstan 46. In this state, the tape guide device 64 is in a state where recording and reproduction are possible.

Next, each part of the above-described signal recording / reproducing apparatus other than the tape guide device main body 200 will be described in more detail with reference to specific examples. Note that, in the following description, the reference numerals “s” attached to the respective parts indicate that they relate to the S-side reel, and “t” indicates that they relate to the T-side reel. When the portions denoted by "t" are denoted by the same reference numerals, the configurations are the same. Therefore, in such a case, one part in the figure is given the same reference numeral with the same reference numeral with "s" attached and the same reference numeral with "t" attached, and the description is given with "s". The description will be made using the reference numerals, and the description of the reference numerals with “t” will be omitted. First, the phase control of the drive signal and the temperature compensation will be described. In order to operate the tape guide device main body 200 efficiently, it is sufficient to drive the tape guide device 200 at a resonance point (the maximum point of the impedance, the frequency is, for example, 150 kHz ± 5 kHz to 10 kHz). This is because the driving is performed by current control, and the higher the impedance, the larger the power that can be generated with a smaller current. However, it has been confirmed that the resonance point changes depending on the temperature (in one example, about 9 Hz at 1 degree). When the constant frequency control is performed, the impedance changes depending on the temperature, and a constant output cannot be obtained. . FIG. 8 is a graph showing the impedance and phase characteristics near the resonance frequency, with the left vertical axis representing impedance (Ω), the right vertical axis representing phase (deg), and the horizontal axis representing frequency (KHz). The curve indicating the impedance corresponds to the vertical axis (impedance) on the left side, and the curve indicating the phase corresponds to the vertical axis (phase) on the right side. This FIG.
As shown in the figure, the resonance point Fr is a place where the impedance is the highest. The phase changes greatly near the resonance point Fr, and the correlation is substantially constant depending on the temperature. Therefore, a region from the vicinity of the maximum change point of the phase indicated by the dashed line to the vicinity where the phase becomes constant is set as the phase control region, and the phase control is performed in this phase control region to maintain a constant impedance. Therefore, in this example, a so-called frequency scan is performed to detect the resonance point, for example, when the tape guide device main body 200 is replaced or first used. The frequency scan is performed by sweeping the vibration frequency while keeping the drive current for driving the tape guide device main body 200 constant, and detecting the drive voltage at that time. The drive voltage changes according to the change in impedance, and reaches a maximum at the resonance point. Therefore, the resonance point can be detected by searching for the point where the drive voltage is the maximum.

The frequency scan and the phase control after this frequency scan are performed by the phase detection circuit 121s shown in FIG.
121t is used. FIG. 9 shows this phase detection circuit 121s,
A specific example of 121t is shown. That is, in FIG.
Reference numeral 34 denotes an amplifier circuit. One of the connection lines connecting the drive circuit 112s and the ultrasonic vibrator 113s is connected to one terminal of the amplifier circuit 134, and the drive circuit 112s is connected to the other terminal of the amplifier circuit 130. And ultrasonic transducer 113s
The other of the connection lines that connect between
The drive signal from 2s is extracted as a voltage signal. 135
Is a pulse generator, and this pulse generator 13
Reference numeral 5 indicates that the sine wave voltage signal from the amplifier circuit 134 is formed into a rectangular voltage signal. This voltage signal is supplied to the phase detector 138. Reference numeral 136 denotes an amplifier circuit.
Drive terminal 112s and ultrasonic vibrator 11
One end of a resistor R1 connecting between 3 s is connected, the other end of the resistor R1 is connected to the other terminal of the amplifier circuit 130,
The drive signal from the drive circuit 112s is extracted as a current signal. Reference numeral 137 denotes a pulse generator. The pulse generator 137 converts a sine wave current signal from the amplifier circuit 136 into a rectangular voltage signal. This voltage signal is supplied to the phase detector 138. The phase detector 138 detects a phase shift between the voltage signal from the pulse generator 134 and the voltage signal from the pulse generator 137, and supplies the detected phase detection signal to the control unit 100 via the low-pass filter 139.

Reference numeral 145 denotes an amplifier circuit. One of the connection lines connecting the drive circuit 112s and the ultrasonic vibrator 113s is connected to one terminal of the amplifier circuit 145, and the other terminal of the amplifier circuit 145 is connected. The other of the connection lines connecting the drive circuit 112s and the ultrasonic vibrator 113s is connected to the terminal, and a drive signal from the drive circuit 112s is extracted as a voltage signal. This voltage signal is supplied to the peak hold circuit 14
6. In the control unit 100, the driving circuit 112s
Is constant. The control unit 100 outputs an offset signal corresponding to the phase detection signal and a control signal for phase control to the temperature compensation circuit 111, respectively.
s and a peak hold circuit 120 composed of an amplifier circuit 145 and a peak hold circuit 146.
If it is determined from the substantially DC voltage signal from s that the maximum drive voltage has been reached, the offset data at that time and the temperature data from the temperature sensor 108 are stored.

Next, the above-described temperature compensation will be described with reference to FIG. As shown in FIG. 10, the temperature compensation includes the temperature compensation circuits 111s and 111s described in FIG.
11t and a temperature sensor 108 are used. In FIG. 10, an offset signal and a control signal from the control unit 100 are added to an adder 14 constituting a temperature compensation circuit 111s.
0 is added, and this added signal is supplied to the drive circuit 112s. Reference numeral 145 denotes an amplifier circuit.
5 is connected to one terminal of the drive circuit 112s and the ultrasonic vibrator 1
One of the connection lines connecting between the 13 s and 13 s is connected, and the other terminal of the drive circuit 112 s and the other of the connection lines connecting between the ultrasonic vibrator 113 s are connected to the other terminal of the amplifying circuit 145. The driving signal is extracted as a voltage signal. This voltage signal is supplied to the peak hold circuit 146. The peak hold circuit 146 converts the sine wave voltage signal from the amplifier circuit 145 into a substantially DC voltage signal, and supplies this voltage signal to the control unit 100. The control unit 100 changes the offset signal and the control signal based on the temperature data from the temperature sensor 108.

FIG. 11 is a graph showing the relationship between the resonance frequency and the temperature, where the vertical axis represents the resonance frequency (KHz) and the horizontal axis represents the temperature (° C.). As is apparent from FIG. 11, the resonance frequency is set to, for example, 149.85 KHz to 150.4 KHz.
Within this range, compensation can be made from −10 ° C. to + 50 ° C., and in this example, further, −2
0 ° C to + 80 ° C so that it can still compensate. Since compensation in this range is possible, even if the tape guide device main body 200 generates heat due to vibration, good driving can be always performed.

Next, the operation of the above-described frequency scanning and temperature compensation will be described with reference to the flowchart of FIG. First, in step 300, a gain data set, that is, the control unit 100 sets predetermined gain data for frequency scanning. Thereby, the drive circuit 112
The ultrasonic vibrator 11 of the tape guide device main body 200
The level of the drive signal supplied to 3s becomes constant. Then, the process proceeds to step 310. In step 310, the temperature is detected based on the temperature data from the temperature sensor 108. Then, control goes to a step 320. Step 320
Then, the control data supplied to the adder 140 of the temperature compensation circuit 111s shown in FIG. 10 is made into data corresponding to the detected temperature data. Then, control goes to a step 330. At step 330, control data is set. Thereby, temperature compensation is performed. Then, control goes to a step 340. In step 340, a frequency scan is performed.
Then, control goes to a step 350. In step 350, as described above, the offset data and the frequency scan end flag near the resonance point frequency at which the drive voltage becomes maximum are stored. Then, control goes to a step 360.
In step 360, the gain data is reset. Then, control goes to a step 370. In step 370,
Reset control data. And it ends.
In this method, control data is varied according to the temperature at the time of frequency scanning, thereby obtaining offset data at normal temperature. In this method, the control unit 100 stores the offset data and the end of the frequency scan. Only the flag may be used, and after this frequency scan, the phase control can be performed immediately.

Next, another method of frequency scanning will be described with reference to FIG. First, in step 400, a gain data set, that is, the control unit 100 sets predetermined gain data for frequency scanning. As a result, the tape guide device main body 20 is driven by the drive circuit 112s.
The level of the drive signal supplied to the zero ultrasonic transducer 113s becomes constant. Then, control goes to a step 410. In step 410, a frequency scan is performed. Then, control goes to step 420. In step 420, as described above, the offset data near the resonance point frequency at which the drive voltage becomes maximum, the temperature data from the temperature sensor 108, and the frequency scan end flag are stored. Then, control goes to a step 430. In step 430, the gain data is reset. And it ends. In this example,
The control unit 100 stores the temperature at the time of the frequency scan in addition to the offset value, and calculates the difference between the temperature data at that time and the stored temperature data during the subsequent phase control,
The offset data is compensated from this difference. Therefore, in this method, phase control can be performed regardless of the phase control range.

The above two methods differ only in whether the temperature compensation is performed during frequency scanning or phase control. By the way, in this example, the frequency scan is performed only once at the time of exchanging the tape guide device main body 200 or at the beginning of use, and the phase control can be immediately performed under any condition thereafter. . As shown in FIG. 9, the phase control after performing the frequency scan supplies the phase detection signal from the phase detector 138 to the control unit 100 via the low-pass filter 139.
The control data (control signal) to be supplied to the drive circuit 112s is varied according to the signal supplied with 00. Thus, the tape guide device main body 200 can always be driven at the above-described resonance point, and efficient driving can be performed.

Next, power control will be described with reference to FIG. This power control is performed by the drive circuit 112 shown in FIG.
s (same for 112t) is used. Hereinafter, the constant power control will be described with reference to FIG. In FIG. 4, reference numeral 142 denotes a voltage control oscillator (VCO). The voltage control oscillator 142 oscillates at a frequency corresponding to the voltage of the control signal from the temperature compensation circuit 111s and the sum signal of the offset signal. A signal of a sine wave due to this oscillation is supplied to the gain controller 143. The gain controller 143 is a voltage control oscillator 142
The gain of the sinusoidal signal is varied according to the gain data from the control unit 100. Reference numeral 144 denotes an amplifier circuit such as a driver. The amplifier circuit 144 converts a sine wave signal from the gain controller 143 into a drive signal, and supplies the drive signal to the ultrasonic vibrator 113s of the tape guide device main body 200. Thus, the tape guide device 20
0 is driven.

Reference numeral 145 denotes an amplifier circuit.
The amplifier 144 and the ultrasonic vibrator 113 are connected to one terminal of
s is connected to one of the connection lines connecting the s and the other terminal of the connection line connecting the amplifying circuit 144 and the ultrasonic vibrator 113 s to the other terminal of the amplifying circuit 145. The driving signal is extracted as a voltage signal. This voltage signal is supplied to the peak hold circuit 146. This peak hold circuit 146 is
The voltage signal of the sine wave from No. 5 is converted into a substantially DC voltage signal, and this voltage signal is supplied to the control unit 100. Reference numeral 147 denotes an amplification circuit. One of the connection lines connecting the amplification circuit 144 and the ultrasonic vibrator 113 s is connected to one terminal of the amplification circuit 147, and the other end of the amplification circuit 145 is connected to the amplification circuit 147. The other of the connection lines connecting the circuit 144 and the ultrasonic transducer 113s is connected, and the drive signal from the amplifier circuit 144 is extracted as a voltage signal. This voltage signal is supplied to the peak hold circuit 148. The peak hold circuit 148 converts the sine wave voltage signal from the amplifier circuit 147 into a substantially DC voltage signal, and converts this voltage signal into the control unit 10.
Supply 0.

The control unit 100 includes a voltage signal from a peak hold circuit 120s composed of an amplifier circuit 145 and a peak hold circuit 146, a current signal from a peak hold circuit 118s composed of an amplifier circuit 147 and a peak hold circuit 148, Further, based on the phase detection signal from the phase detection circuit 119s, the active power for driving the tape guide device main body 200 is obtained. Further, a tape running mode signal from the signal processing unit of the video tape recorder main body 300 described with reference to FIGS.
Video tape recorder body 30 supplied via the
0, a tape speed information signal from the signal processing unit, input terminal T
3 based on the tension information from the tension detection circuits 117s and 117t described with reference to FIG. 3 and supplied to the video tape recorder in the mode (so-called jog or shuttle operation) described later with reference to FIGS. And the like, and the data of the tape tension is determined, and the gain data supplied to the gain controller 143 is changed according to the data.

FIG. 14 is a graph (FIG. 14A) in which the vertical axis represents power (W) and the horizontal axis represents time (sec). The vertical axis represents tape speed (mm / sec), and the horizontal axis represents time (sec). Graphs (FIG. 14B) are shown, respectively, showing the state of power control in the fast-forward running mode. As shown in FIG. 14B,
When the tape speed rises and reaches, for example, the maximum fast-forward speed of 5000 mm / sec, a constant speed is maintained. Also, as shown in FIG. 14A,
When the tape speed rises, that is, at the moment when the friction changes from static friction to dynamic friction, the power is increased to 0.6 W, immediately after that, the power is set to 0.4 W, and when the speed reaches 1000 mm / sec, the power is set to 0 W. As described above, the power control on the time axis is performed by the gain controller 143 based on the gain data from the control unit 100. By controlling in this way, it is possible to prevent the high frictional force generated at the moment of transition from static friction to dynamic friction from acting on the tape, and in the low speed region, the frictional force can be reduced and the high speed region can be reduced. Then, by stopping unnecessary ultrasonic vibration, efficient operation of the apparatus can be realized. FIG. 15 is a graph (FIG. 15A) in which the vertical axis represents power (W) and the horizontal axis represents time (msec), the vertical axis represents tape speed (mm / sec), and the horizontal axis represents time (msec).
Each of the graphs (c) and (c) of FIG. 15B is shown, and shows the state of power control until the steady speed is reached and thereafter. As shown in FIG. 15, 100 msec until the running speed of the tape reaches, for example, a steady speed of 130 mm / sec.
During time c, power is input to 0.6 W and the steady-state speed 1
After reaching 30 mm / sec, the power is set to 0.4 W. As a result, the abnormal tension in the static friction region was eliminated, and the rise time, which conventionally required a time of 1000 msec or more, was reduced to about 1/10. FIG.
6 is a graph in which the vertical axis represents power (W), the horizontal axis represents time t, and the on / off state of the reproduction mode is represented by the vertical axis, the horizontal axis represents time t, and the jog mode is represented by on / off, and FIG. 4 shows a composite graph of a graph in which the horizontal axis represents time t, and shows a state of power control when a transition is made from the reproduction mode to the jog mode. As shown in FIG. 16, the input voltage which was 0.4 W in the steady state in the reproduction mode was changed to the input voltage in the jog mode.
0.8W. Thereby, in jog mode,
At a tape speed with many changes, the frictional resistance is reduced, and the response (response of the tape speed to a tape running command) is improved. The power control using the tape tension as a parameter is performed, for example, when the tape 59 is connected to the supply reel 4.
This is effective in a mode in which the tape 59 is transferred by the drive of the take-up reel 43, that is, in a mode in which the tape 59 is not transferred by the pinch roller 65. This control is performed by controlling the power supplied to the ultrasonic vibrators 113s and 113t so that the ratio of the tensions obtained by the tension detectors 116s and 116t of the supply-side tension arm 152 and the winding-side tension arm 152 becomes constant. Is realized by controlling

Next, distortion detection will be described. In the tape guide device, the ultrasonic vibrators 113s and 113t of the tape guide device main body 200 are subjected to severe usage such as vibrating at a resonance point at a high frequency. Therefore, the ultrasonic vibrators 113s and 113t are separated from the guides 114s and 114t, respectively. , Ultrasonic transducers 113s and 113t
In some cases, defects such as cracks may be induced on the surface. However, the effect of reducing friction caused by the contact between the tape 59 and the guides 114s and 114t by the ultrasonic vibrators 113s and 113t is not so much affected by the vibration waveform, so that it is difficult to detect these initial defects. By the way, when the current control is performed, if the ultrasonic vibrators 113s and 113t are peeled off from the guides 114s and 114t, or if a defect such as a crack occurs on the surface of the ultrasonic vibrators 113s and 113t, the ultrasonic vibrator 113s And 113t cause higher-order vibration, and as a result, distortion occurs in the voltage waveform of the drive signal. FIG. 17 is a graph showing the spectrum components of the drive voltage of the tape guide device main body, with the vertical axis representing the spectrum (dB) and the horizontal axis representing the frequency (KHz). This figure 1
As is clear from FIG. 7, each of the second order (2F) from the resonance point Fr
r) Third-order (3Fr) and higher harmonic components appear. Therefore, in this example, the distortion detection circuit 12 shown in FIG.
By using 1s and 121t, a resonance frequency component is extracted from a drive signal, distortion is detected from a harmonic component, and early detection of the above-described defect or the like can be achieved.

Hereinafter, the distortion detection will be described with reference to FIG. In FIG. 18, reference numeral 130 denotes an amplifier circuit.
One of the connection lines connecting the drive circuit 112s and the ultrasonic vibrator 113s is connected to one terminal of the amplifier circuit 130, and the drive circuit 112s and the ultrasonic vibrator 113s are connected to the other terminal of the amplifier circuit 130. The other of the connection lines that connect between them is connected, and a drive signal from the drive circuit 112s is extracted as a voltage signal. The amplifier circuit 130 supplies the voltage signal to the peak hold circuit 133 through a high-pass filter (HPF) 131 and a band elimination filter (BEF) 132. By passing the voltage signal from the amplifier circuit 130 through the high-pass filter 131 and the band elimination filter 132, the resonance frequency component is extracted as shown by the broken line in FIG. The peak hold circuit 133 converts the voltage signal from which the resonance frequency component has been extracted into a substantially DC voltage signal, and supplies this voltage signal to the control unit 100. The control unit 100 determines from the voltage signal whether or not the tape guide device main body 200 has the above. For example, a display device may be connected to the control device 100, and when the control device 100 determines that there is an abnormality, a display indicating an abnormality may be performed. in this way,
The resonance frequency component is extracted from the drive signal, and the presence or absence of a harmonic component in the drive signal is detected by a signal obtained by holding the peak of the voltage signal from which the resonance frequency has been extracted. 113t is the guide 114
Even if it is peeled off from the s or 114t or a defect such as a crack occurs on the surface of the ultrasonic vibrator 113s or 113t, it can be detected early.

Next, detection of the tension of the tape will be described. The detection of the tension of the tape makes it possible to confirm the abnormality of the tape guide device main body 200 or the amount of reduced friction. As shown in FIG. 2, the detection of the tape tension is performed by the angle detectors 116s and 116t.
And the tension detection circuits 117s and 117t. This tension detection is performed in FIG.
When the pinch roller 65 and the capstan 46 are separated,
That is, it is performed in the case of the so-called reel mode.
This tension detection may be performed each time the power is turned on to the apparatus as a self-diagnosis by the control unit 100, for example. Further, when the tape is running in the reel mode, when the tension on the S side or the T side is determined, the other tension is uniquely determined. For example, when the tape tension on the S side is a certain value when the tape is traveling in the forward direction, the value of the tape tension on the T side is determined by a guide between the angle detectors 116s and 116t and the rotary head 52 (see FIG. 3) is added. Among the guides, the friction of the rotating guide is very small, and therefore, the tape guide device main body 200 largely affects the increase in the tension (forward the tape).

Hereinafter, the tension detection will be described with reference to FIG. In FIG. 19, reference numeral 151 denotes a magnetic sensing unit, which also serves as the axis of the arm 152.
Further, the magnetic sensing portion 151 is connected to the movable guide 115s by the arm 152. Movable guide 11 of arm 152
The spring 150 is attached at a predetermined position on the 5s side. Further, one end of the magnetic sensing unit 151 is connected to the operational amplifier circuit 14 via the resistor R3.
9 and the other end of the magneto-sensitive section 151 is connected to the non-inverting input terminal (+) of the operational amplifier circuit 149 via the resistor R4, thereby inverting the operational amplifier circuit 149. The input terminal (-) and the output terminal of the operational amplifier circuit 149 are connected via a resistor R2.
The 49 non-inverting input terminal (+) is grounded via a resistor R5. Thereby, for example, a tension detection circuit 117s as a differential amplifier circuit is configured.

As shown in FIG.
51a, a magnet 151c, a magnetically sensitive element 151b, and power supply terminals 151d and 151e. The magnetically sensitive element 151b generates a signal (referred to as an angle information signal) by rotation of a magnet 151c disposed on the shaft 151a. An output signal from the magnetically sensitive element 151c is sent to a tension detection circuit 117S. Supplied.

The movable guide 115s moves in the direction shown by the solid arrow in the figure due to the tension of the tape 59.
As a result, the arm 152 also rotates around the magnetic sensing part 151 also serving as an axis, as indicated by the arrow. Thus, the angle information signal from the magnetic sensing unit 151 is supplied to each of the tension detection circuits 117s constituting the differential amplifier circuit, and the tension detection circuit 117s converts the angle information signal into a tension information signal. Supplied. Similarly, on the T side, a tension information signal is supplied to the control unit 100 by the angle detector 116t and the tension detection circuit 117t. The control unit 100 controls S and T
The tension ratio between the S side and the T side is obtained based on the tension information signal from the side, and the tape guide device main body 2 is determined based on this ratio.
The operation state of 00 is grasped, and based on this, abnormality diagnosis or confirmation of the amount of friction reduction is performed.

FIG. 21 is a graph showing the tension ratio of the S-side and T-side tape tensions when the tape 59 runs in the reel mode in the reverse and forward directions, respectively. The graph on the left shows the case where the tape is run in the reverse direction, and the graph on the right shows the case where the tape is run in the forward direction. The vertical axis is the tension ratio between the S side and the T side, and the horizontal axis is the speed at which the tape runs. In each graph, the broken line indicates the case where the tape guide device main body 200 is driven, and the solid line indicates the case where the tape guide device main body 200 is driven. This is the case where the driving was not performed. In this example, for example, as shown in FIG. 21, a case where the tension ratio is 3.0 or more is determined to be abnormal. As is apparent from FIG. 21, when the tape guide device main body 200 is driven, the tension ratio of 3.0 or more, which is determined to be abnormal, is not obtained at any speed, and the tape guide device main body 200 is not driven. The tension ratio becomes considerably smaller than when the motor is not driven. Thus, the angle detector 116
s, 116t and tension detection circuits 117S, 117
Since the tensions of the tapes on the S side and the T side are obtained from t, the tension ratio between the S side and the T side is calculated by the control unit 100, and the abnormality is determined in accordance with the tension ratio. Is the tape guide device body 20
The friction reduction effect of 0 can be easily confirmed. Further, when the friction reducing effect is not good, the tape guide device main body 200 is controlled so that the slack of the tape 59 can be substantially eliminated when the running state is changed from the running state to the stopped state. When in the state, the start of movement of the tape can be made relatively smooth.

Now, the operation of the entire tape guide apparatus will be described with reference to the flowchart of FIG. First,
In step 100, the command of the ultrasonic vibrator is determined by the system controller 106. If "ON", the process proceeds to step 110, and if "OFF", the process proceeds to step 2.
Move to 70. In step 110, the ultrasonic vibrator 1
It is determined whether 13s and 113t are on, and "YES"
If so, the process proceeds to step 120, and if “NO”, the process proceeds to step 190. In step 120, the phase control is performed by the phase detection circuits 119s and 119t described in FIG. Then, control goes to a step 130.
In step 130, the driving circuit 1 described in FIG.
Power control is performed by 12s and 112T. Then, control goes to a step 140. In step 140, distortion is detected by the distortion detection circuits 121s and 121t described with reference to FIG. Then, control goes to a step 150. In step 150, it is determined whether an abnormality is detected,
If “YES”, the flow shifts to step 160, and “NO”
If so, the process proceeds to step 230. In step 160, the abnormality information is supplied to the system controller 106. Thereby, for example, the system controller 10
The system controller performs an indication on the display device connected to 6 to indicate an abnormality. Then, control goes to a step 170.

In step 170, control data and gain data are stored in the RAM 105, respectively. Then, control goes to a step 180. In step 180, the ultrasonic vibrators 113s and 113t of the tape guide device main body 200 are turned off, respectively. If no abnormality is detected in step 150, the process proceeds to step 230. In step 230, tension is detected by the tension detection circuits 117s and 117t described in FIG. 19 and the angle detectors 116s and 116t described in FIG. Then, control goes to a step 240. In step 240, it is determined whether or not an abnormality has been detected.
If "S", the process proceeds to step 160, and if "NO", the process proceeds to step 100 again. If “NO” is determined in the step 110, the process proceeds to a step 190. In this step 190, it is determined whether or not the frequency scan has already been completed.
00, and if “NO”, the flow proceeds to step 250. In step 200, frequency compensation is performed. Then, the process proceeds to step 210. In step 210, offset data is set. Then, control goes to a step 220. In step 220, the ultrasonic vibrator 113s
And 113t are turned off. And step 1 again
Move to 20. In step 250, FIG. 9 and FIG.
The phase detection circuits 119s and 119t described in
Temperature sensor 108, temperature compensation circuits 111s and 111t
To perform a frequency scan. Then, the process proceeds to step 260. In step 260, offset data, temperature data, and the like are stored in the RAM 105. Then, the process returns to step 100 again. In step 100, "O
If it is determined to be "FF", the process proceeds to step 270. In this step 270, the ultrasonic vibrators 113s and 113s
It is determined whether 3t is off or not, and if "YES", the process returns to step 100. If "NO", step 1 is performed.
Move to 70.

As described above, in this example, the CPU 10
2, the driving circuits 112s and 112t are controlled to change the voltage of the driving signal supplied to the ultrasonic vibrators 113s and 113t in various modes, that is, in accordance with the state of the apparatus. Can be optimized, and efficient operation of the device can be realized in terms of power reduction.

It should be noted that the present invention is not limited to the above-described embodiment, but can take various other configurations without departing from the gist of the present invention.

[0045]

According to the present invention described above, the control means variably controls the vibration amount of the ultrasonic vibration type tape guide based on the operation mode and the tape speed, so that the tape tension is optimized. In addition to this, there is an advantage that an efficient operation of the device can be realized also in terms of power reduction.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a signal recording / reproducing apparatus of the present invention.

FIG. 2 is a configuration diagram showing one embodiment of the signal recording / reproducing apparatus of the present invention.

FIG. 3 is a configuration diagram showing a main part of an embodiment of the signal recording / reproducing apparatus of the present invention.

FIG. 4 is a configuration diagram showing a main part of an embodiment of the signal recording / reproducing apparatus of the present invention.

FIG. 5 is a flowchart for explaining one embodiment of the signal recording / reproducing apparatus of the present invention.

FIG. 6 is a cross-sectional view showing an example of a tape guide device main body for describing the signal recording / reproducing device of the present invention.

FIG. 7 is a top view showing an example of a tape guide device main body used for describing the signal recording / reproducing device of the present invention.

FIG. 8 is a graph showing impedance and phase characteristics near a resonance point for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 9 is a block diagram showing a specific example of a phase detection circuit used for describing the signal recording / reproducing apparatus of the present invention.

FIG. 10 is a block diagram showing a specific example of a temperature compensation circuit for explaining a signal recording / reproducing apparatus of the present invention.

FIG. 11 is a graph showing the relationship between the resonance frequency and the temperature for explanation of the signal recording / reproducing apparatus of the present invention.

FIG. 12 is a flowchart for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 13 is a flowchart for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 14 is a graph showing a state of voltage control in a fast-forward mode for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 15 is an explanatory diagram showing a difference in power before and after reaching a steady speed for explanation of the signal recording / reproducing apparatus of the present invention.

FIG. 16 is an explanatory diagram showing a difference in power between a reproduction mode and a jog mode for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 17 is a graph showing a spectrum component of a driving voltage of a tape guide device main body for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 18 is a block diagram showing a specific example of a distortion detection circuit used for describing the signal recording / reproducing apparatus of the present invention.

FIG. 19 is a diagram showing a specific example of a tension detection circuit and an angle detector for explaining the signal recording / reproducing apparatus of the present invention.

FIG. 20 is a block diagram showing a specific example of a magnetic sensing unit of an angle detector for explaining a signal recording / reproducing apparatus of the present invention.

FIG. 21 is a diagram illustrating the signal recording / reproducing apparatus according to the present invention.
6 is a graph showing the tension ratio on the side.

FIG. 22 is a cross-sectional view illustrating an example of a conventional tape guide device.

FIG. 23 is a top view showing an example of a conventional tape guide device.

FIG. 24 is a graph for explaining an example of a conventional tape guide device.

FIG. 25 is a diagram showing an example in which a tape guide device is mounted on a video tape recorder used for describing a conventional signal recording / reproducing device.

FIG. 26 is a diagram showing an example in which a tape guide device is mounted on a video tape recorder used for describing a conventional signal recording / reproducing device.

FIG. 27 is a graph showing a relationship between a tape speed and a friction coefficient.

[Explanation of symbols]

 59 tape 100 control unit 103s ultrasonic vibrator 103t ultrasonic vibrator 112s drive circuit 112t drive circuit 114s guide 114t guide 118s peak hold circuit 118t peak hold circuit 109 drive unit 120s peak hold circuit 120t peak hold circuit 200 tape guide device main body 500 Detection unit

Claims (1)

(57) [Claims] The tape speed is controlled in a predetermined manner according to an operation mode, and an ultrasonic vibration type tape guide is used as a tape guide member for guiding the tape. In a signal recording / reproducing apparatus for recording and / or reproducing a signal on / from a tape, there is provided control means for variably controlling a vibration amount of the ultrasonic vibration type tape guide based on the operation mode and the tape speed. A signal recording / reproducing apparatus characterized in that: