JP3344103B2 - Tension detection device and tension control 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 tension detecting device for detecting a tension applied when a tape runs while being wound and slidably contacted between one reel and the other reel on the outer peripheral surface of a drum of a rotary head device. The present invention relates to a tension control device that controls tension using the tension detection device.

[0002]

2. Description of the Related Art A recording / reproducing apparatus using a tape-type recording medium sends a tape from a supply reel to a take-up reel, and conversely, a tape tension when sending a tape from a take-up reel to a supply reel. The tape tension is controlled to a predetermined tension while being detected by the tension pickup. In order to prevent the tape from sagging at the predetermined tape tension, the recording / reproducing apparatus applies a pulling force to the tape as a back tension in a direction opposite to a traveling direction of the tape during recording or reproduction.

Further, it is known that the tape tension changes according to the operation mode of the recording / reproducing apparatus.

As a method of detecting the tape tension, for example, there is a method using one tension pickup (hereinafter, referred to as one tension pickup method) and a method using two tension pickups (hereinafter, two tension pickup method).

In the 1-tension pickup method, a tension pickup is provided at the entrance of the drum of the recording / reproducing apparatus, that is, between the drum and the supply reel. The tension detection in this case is used only in, for example, a normal reproduction mode, that is, a so-called FWD mode.

In the two tension pickup method,
One tension pickup is arranged for each of the drum entrance side and the drum and the take-up reel with respect to the drum. When the two-tension pickup method is adopted, the recording / reproducing apparatus uses a tension pickup on the drum entrance side in the fast-forward reproduction mode, and uses a tension pickup on the drum exit side in the reverse reproduction mode.

An apparatus using such a tension pickup performs speed control in a normal reproduction mode or a reverse reproduction mode using a capstan FG signal from a capstan motor. For this reason, this apparatus can perform tracking servo by performing control requiring accuracy.

[0008]

By the way, as the size of the recording / reproducing apparatus is reduced, the recording / reproducing apparatus is being developed with the aim of further improving the function. For example, in an 8 mm VTR which is one of the recording / reproducing apparatuses, if priority is given to miniaturization of the apparatus, it is difficult to dispose two tension pickups in the 8 mm VTR in terms of space. In this case, only the 1-tension pickup method can be used for the 8 mm VTR to control the tape tension.

However, in the 1-tension pickup method, the tape tension can be detected only in the so-called FWD mode as described above.
As for the VTR, the tape tension is detected only in the above-mentioned FWD mode, and the function up is suppressed.

In addition, such an 8 mm VTR cannot guarantee a tape tension in a mode other than this mode, for example, a reverse reproduction mode.

However, recently, tapes having a thinner base layer have been marketed to increase the recording time. If the back tension or the like is not controlled and the tension is not controlled in a mode other than the so-called FWD mode, an excessive load is applied and the tape may be damaged. When such a thin tape is used, it is necessary for the 8 mm VTR to detect the tape tension applied to the tape for each operation mode and to control so that an appropriate tension can be applied.

It is known that high-speed rotation cannot be performed by the control using the capstan FG signal described above. Here, when the tape is run without pressing the pinch roller against the tape in order to perform the high-speed running of the tape, it is not possible to perform a control requiring precision such as tracking servo.

Further, if both the tracking servo and the speed control are to be satisfied, a corresponding cost and a large motor are required. In particular, when the size of the motor is increased, the height of the device cannot be suppressed to, for example, a size of 3.5 inches.

The present invention has been made in view of the above-mentioned circumstances, and a tension detecting device capable of detecting a tape tension corresponding to each operation mode while reducing the size of a recording / reproducing device. The purpose is to provide.

It is another object of the present invention to provide a tension control device capable of controlling the tape tension according to each operation mode while reducing the size of the recording / reproducing device.

[0016]

SUMMARY OF THE INVENTION A tension detecting device according to the present invention is used for winding a tape between one reel and the other reel on the outer peripheral surface side of a drum of a rotary head device and causing the tape to travel while sliding. In a tension detecting device for detecting such a tape tension, a rotatable guide roller slidably in contact with the tape is disposed on one end side, and a rotation arm member defining an interval between the guide roller and a rotation shaft positioned at a rotation center. A first position detecting means comprising two magnets disposed on a substrate which rotates integrally with a rotation shaft of the rotation arm member; and a relative rotation of the first position detection means. A second position detecting means comprising a Hall element fixedly disposed at a position for detecting a moving amount, and an urging means for urging the rotary arm member in a direction in which the tape and the guide roller are in sliding contact with each other; It is characterized by having.

Here, the distance between the rotation shaft of the rotation arm member and the guide roller is such that the equilibrium position between the rotation torque caused by the tension coil spring and the tape tension is rotated at least about ± 15 ° with respect to the reference position. Set to distance. The tension detected by the rotation of the magnet and the Hall element has a detection range of 7 to 20 g.
One tension detecting device is provided between the drum and the supply reel that supplies the tape.

Further, the tension control device according to the present invention comprises two reel motors for independently driving the supply and take-up reels, respectively, while winding and slidingly contacting the outer peripheral surface of the drum of the rotary head device. Used in the tape drive mechanism used, in a tension control device that controls the tape tension by supplying a control signal according to the operation mode to each reel motor, a rotatable guide roller that slides on the tape is disposed on one end side, A rotating arm member defining a distance between the guide roller and a rotating shaft positioned at the center of rotation; and a tape tension detecting means disposed between the drum and a supply reel for supplying tape. The tape tension detecting means is a first position detecting means comprising two magnets disposed on a substrate which rotates integrally with the rotation axis of the rotation arm member. When, it is characterized in that a second position detecting means comprising a Hall element fixed disposed at a position to detect a relative rotational amount of the position detecting means of the first.

[0019]

In the tension detecting device according to the present invention, a rotatable guide roller is provided at one end as a tension arm for slidingly contacting the tape, and the distance between the guide roller and a rotation shaft positioned at the center of rotation is defined. The rotation position at which the rotational torque generated by the urging force of the tension coil spring and the tape tension are balanced is set to at least a larger rotation amount than the conventional position with respect to the reference position, and a single pickup is used to detect the tension in the operation mode of the device to be used. I correspond.

By setting the distance between the rotation axis of the tension arm and the guide roller at a distance for rotating at least about ± 15 ° with respect to the reference position in the balance between the rotation torque and the tape tension, a plurality of modes are generated. Detection is performed within the range of the tape tension to be performed.

Using a magnet as the first position detecting means,
By using a Hall element for the second position detecting means,
The relationship between the rotation angle of the tension arm and the tape tension in each mode can be adjusted so as to be substantially linear in each range.

The tension detected with the rotation is 7 to
By detecting a range of about 20 g, tension detection in a plurality of modes can be supported.

By arranging one between the drum and the supply reel for supplying the tape, the space required for the arrangement can be reduced without using two pickups for detecting the tension in a plurality of modes as in the prior art. .

The tension control device according to the present invention presses the tape against the pinch roller in the normal reproduction mode and the reverse reproduction mode while satisfying the control of the tracking servo and the like, and releases the pinch roller during the search to separate the tape from the tape. To run at high speed.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a tension detecting device and a tension control device according to the present invention will be described below with reference to the drawings.

The tension detecting device is, for example, a device for detecting the tension applied when a tape is run between a supply reel and a take-up reel while the tape is wound around the outer peripheral surface of a drum of a rotary head device while slidingly contacting the same. Used.

This tension detecting device is disposed between the supply reel and the entrance of the drum for sliding the tape, for example, as described later, between the supply reel and the take-up reel. FIGS. 1 to 3 show the tension detecting device provided during this time, and the description will be made with reference to these drawings.

As shown in FIG. 1, for example, the tension detecting device 1 includes a tension arm 11 for rotating around a rotation shaft 10 and a guide roller 12 on one end 11a of the tension arm 11. A substrate 13 having the same rotating shaft 10 is attached below the tension arm 11. The substrate 13 rotates integrally with the tension arm 11 about the rotation shaft 10.

A pair of magnets 14 are provided on the tip 13a side of the substrate 13. Also, this magnet 1
At a fixed position corresponding to 4, a Hall element 15 is provided. One end 14a and the other end 14b of the magnet 14 correspond to the S pole and the N pole, respectively.

A pin 11b, for example, is provided upright on the tension arm 11 at a position facing the magnet 14 so as to lock one end 16a of the tension coil spring 16. The other end 16b side of the tension coil spring 16 is attached to, for example, a pin 17 erected on a chassis or a substrate of a device to which the tension detecting device is attached.

The tension coil spring 16 always urges the tension arm 11 in the direction of pressing the tension arm 11 in the tape 2 direction. The urging force of the tension coil spring 16 is
, A spring constant is set so as to balance the rotational torque generated by pushing the guide roller 12 of the tension arm 11. As will be described in detail later, the spring constant required for the operation in a plurality of modes is completed with only one value by considering the length and arrangement of each part, as will be described in detail later.

The other end 1 of the tension arm 11
On the 1b side, a balancer 18 is provided. The balancer 18 can detect the tape tension even when the tension detecting device is installed in a vertical direction such that the tension detecting device is not set horizontally but vertically set, for example, in the installation direction of the device equipped with the tension detecting device. This is for adjusting the balance so that the difference from the case of the horizontal arrangement does not appear.

Further, the dimensions of the members of the tension detecting device will be specifically described.

First, the reference interval <a> in FIG.
Includes two guide line perpendicular from the midpoint position to the straight line L _GG which connects the guide pins 19, 20 of pins 19, 20 L _GP provided in the tape path route in supplying the tape to the drum is in units of distance between the straight line L _RP passing through the center of the rotation shaft 10 parallel to the straight line L _GP. This reference interval <
Based on a> = 1, the interval <b> between the guide pins 19 and 20 is <b> = 20, the interval between the straight line L _GG and the straight line L _RPP perpendicular to the straight line L _RP passing through the center of the rotating shaft 10. <C> is
<C> = 4.

The center of the rotating shaft 10 and the magnet 14
Is set to 4.5 mm. The tension coil spring 16 uses a spring constant k = 0.02 N / mm. When such dimensions and positional relationship are set as reference positions, the winding angle θ of the tape 2 around the guide roller 12 is θ = 45 ° ± 5 °.

Next, in this tension detecting device, when the tension received from the tape 2 is the minimum tension, that is, when the reference position shown in FIG.
When rotated by -15 °, a straight line _LGP1 passing through the center of rotation of the guide roller 12 perpendicular to a straight line connecting the guide pin 19 and the guide roller 12, and a straight line passing through the center of the rotating shaft 10 parallel to the straight line _{LGP1 Assuming} that the distance <a _′> = 1 from L _RP1 ,
The tangent line L _G19 and this straight line L _G19 are parallel to the straight line perpendicular to the straight line L _RP1 and on the side of the guide pin 19 not in sliding contact with the tape 2.
The distance between the tangent line _LG20 and the guide pin 20 parallel to
6.7>. The winding angle θ of the tape around the guide roller 19 is θ = 65 °.

Next, when the tension received from the tape in this tension detecting device is the maximum tension,
That is, when FIG. 1 is set as the reference position, when the tape 2 is rotated clockwise by + 15 °, the straight line L _GT in the tangential direction at the midpoint of the range where the tape 2 is wound around the guide roller 12 is parallel to the straight line L _GT . _Assuming that the distance <a ″> = 1 from a straight line L _GC passing through the center of rotation of the guide roller 12, a straight line L ₁₀ perpendicular to these straight lines and passing through the center of the rotating shaft 10 and a straight line passing through the center of the guide pin 19. distance between L ₁₂ will <1.8>. the wrap angle theta to the guide roller 12 the tape 2, there theta = 10 °.

When the rotational torque at the time of the minimum tension and the rotational torque at the time of the maximum tension are represented by a ratio, the rotational torque ratio is each <6.7.
> And <1.8>.

By arranging in this manner, the product of the value of the tension and the rotation torque ratio at the time of the minimum tension is about 40, as shown by the relationship between the rotation angle of the tension arm 11 and the tension in FIG. Value, there is no measured value at the maximum tension, but 25 near -15 の
A similar calculation using (g) yields approximately 45. Conventionally, there is a large difference between the minimum tension and the maximum tension.

Incidentally, in order to bridge this difference, the spring constant k of the tension coil spring 16 used at the time of the minimum tension and at the time of the maximum tension must be changed correspondingly. Further, in the conventional tension detection device, the rotation angle can be only about ± 9 °, and the tension detection range is usually about 5 ± 1 (g).

However, in the tension detecting device according to the present invention, by taking the above-mentioned arrangement relationship, one tension constant can cope with both tensions.
Thus, the tension detection range can be set to about 7 to 20 (g), and the dynamic range can be widened.

In the tension detecting device, for example, the output voltage from the Hall element 15 with respect to the tension is obtained as shown in FIG. When the tension is in the range of about 11 to 20 (g), the output voltage is as small as about 0.65 (V). When using this output voltage to calculate the tension applied as a load to the tape, taking advantage of this tendency that is close to linear,
An accurate tension amount can be detected. The region where the tension is low, about 6 to 8, also shows a sufficiently linear output voltage characteristic. Thus, it can be seen that accurate tension detection is possible in a tension detection range of about 7 to 20 (g).

Next, a tension control device according to the present invention will be described with reference to FIGS.

Here, this tension control device is, for example, a 3.5-inch standard height 8 mm VTR.
(Hereinafter referred to as 8 mm VTR). This 8
The mmVTR can independently drive the supply reel and the take-up reel.

As shown in FIG. 6, for example, as shown in FIG. 6, the tension control device includes one tension pickup 100 between the S reel motor 30 for rotating a supply reel (hereinafter referred to as S reel) and the drum 6 in FIG. It has a reel on the side where the tape is wound and a signal processing unit 33 for controlling the tape tension of the reel on the side where the tape is sent out in accordance with the operation mode based on the tension detection signal from 100.

The 8 mm VTR includes an S_FG amplifier 34 that amplifies a signal from a frequency generator (hereinafter, referred to as an S reel FG) that changes a frequency signal output according to the rotation speed of the S reel 30A, and a take-up reel (hereinafter, referred to as an S reel FG). T
A frequency generator (hereinafter referred to as a T reel FG) that changes a frequency signal to be output according to the rotation speed of the reel 31A
T_FG amplifier 35 for amplifying the signal from
A frequency generator (hereinafter, CAPFG) that changes a frequency signal to be output according to the rotation speed of the capstan motor 32
CAP_FG amplifier 36 that amplifies the signal from
Are supplied to the SFG, TFG, and CAPFGWO arithmetic processing unit 33, which are signals detected respectively. These signals are supplied to an arithmetic processing circuit 33a in the arithmetic processing unit 33.

As shown in FIG. 7, the tension pickup 100 detects the tension of the tape running between the S reel 30A and the T reel 31A. An output signal from the Hall element is used for tension detection. The tension pickup 100 supplies a tension detection signal to the signal processing unit 33 via the amplifier 37. The tension pickup 100 detects the tape tension of the reel on which the tape is wound and the reel on which the tape is sent out in accordance with the operation mode of the apparatus described later.

The signal processor 33 converts the tension detection signal into a digital signal at the A / D port and supplies the digital signal to the arithmetic processing circuit 33a. Although not shown, the arithmetic processing circuit 33a obtains a position error signal by weighting the difference between the tape position signal and the reference tape position, and corrects, for example, the reel motor speed of the side on which the tape is wound. Further, the arithmetic processing circuit 33a controls the back tension of the reel motor on the side of sending the tape in accordance with the position error signal. These control signals are output from the arithmetic processing circuit 33a to the LPF units 38, 39, and 40 as pulse width modulated (hereinafter referred to as PWM) output signals as shown in FIG.

Each of the LPF units 38, 39, and 40 limits the band of the output, and then amplifies the output via amplifiers 41, 42, and 43, and switches the switching transistors 44, 45, and 46.
Supply to the gate.

The switching transistors 44, 4
Reference numerals 5 and 46 denote emitter outputs of the S reel motor 3 respectively.
0, a motor driver 48 for driving the capstan motor 32, and the T reel motor 3.
1 is supplied to a motor driver 49 for driving the motor 1.

The motor drivers 47 and 49 receive a reel-on signal for turning on the reel motor from the signal processor 33 and a reel forward signal (reel F) as a control signal for setting the rotation direction of the reel to the forward direction.
WD). Further, a cap-on signal for turning on the operation of the capstan motor and a capstan forward signal (cap FWD) as a control signal for rotating the capstan motor in the forward direction are supplied from the signal processing unit 33 to the motor driver 48. ing.

Next, the control of the four kinds of operation modes will be described after the loading of the control of the tension control device is described.

First, the tape 2 is pulled out from the tape cassette by the guide posts 3a and 3b from the S reel 30A during loading. At this time, the tape 2 is guided by the guide post 3a to the guide post 4 and the guide roller 10 of the tension pickup 100 which is a tension detecting device.
1. Sliding contact with the impedance roller 5 respectively
It is supplied to the inlet side of the drum 6. The tape 2 is pulled out of the tape cassette by the guide post 3b on the exit side of the drum 6, and at this time, the tape 2 is also pulled out so as to be in sliding contact with the impedance roller 7, the capstan 8, and the guide post 9. In this way, the tape in the tape cassette becomes 8
It is loaded on the drum 6 of the mmVTR. This 8m
The mVTR has four operation modes. Hereinafter, description will be made in order.

The arrangement and operation relationship shown in FIG.
This shows a so-called FWD mode state.

In the FWD mode, the pinch roller 50 is pressed against the capstan 8. The capstan 8 is provided with a capstan motor. The speed of the tape 2 is controlled by the driving of the capstan motor, that is, the CAPFG signal detected by the capstan FG, and the tape 2 is wound around the T reel.

In this winding, a T reel motor (not shown) provided for driving the T reel is controlled by constant voltage control. The T-reel motor detects the winding diameter, outputs a voltage corresponding to the winding diameter, rotates clockwise, and shifts from BOT to E
Open loop control is performed so that the tension is almost constant until OT.

In the S reel 30A, a so-called forward back tension is applied to the tape to prevent the tape from becoming loose. In controlling the back tension, the position of the tension pickup 100 is detected from the output of the Hall element. The tension control device increases or decreases the voltage of the motor driver 47 based on a control signal from the arithmetic processing circuit 33a so that the position of the tension pickup 100 is at a regular position. In this way, the closed loop control is performed so as to keep the tension in the drum 6 within a predetermined range.

When the tape 2 is actually brought into sliding contact with each part, the tension applied to the tape in the operation mode is about 7 to 9 based on the output from the tension pickup 100.
(G). Tape tension control is performed based on the detected value.

Next, the arrangement and operation relationship in FIG. 7 show a state of a so-called RVS mode during reverse reproduction. In this mode, images and the like can be searched.

Also in the RVS mode, the pinch roller 50 is pressed against the capstan 8, that is, the so-called pinch roller is turned on. The capstan 8 is rotated in a direction opposite to that of the FWD by driving the capstan motor to pull the tape 2 to apply tension. In this case, the take-up reel side is the S reel 30A and the tape sending side is the T reel 31A. The operations of the T reel motor and the capstan motor perform exactly the same operations as in the FWD mode described above. When the pinch roller 50 is turned on, the tape 2 is pressed against the capstan 8 to control the winding tape tension on the S reel 30A.

Also in the RVS mode, the S reel motor detects the position of the tension pickup 100 from the output of the Hall element, as in the case of the FWD mode. The tension control device includes a tension pickup 1
Arithmetic processing circuit 33 so that the position of 00 is at the normal position.
The voltage of the motor driver 47 is increased or decreased based on the control signal from a. However, the running direction of the tape 2 is FWD
Tension is higher because the anti-clockwise rotation is opposite to that in the mode. In this way, the closed loop control is performed so as to keep the tension in the drum 6 within a predetermined range.

The tension applied to the tape in the operation mode by actually bringing the tape into sliding contact with each part is about 11 to 13 based on the output from the tension pickup 100.
(G). Tape tension control is performed based on the detected value.

Next, the arrangement and operation relationship shown in FIG. 8 show a so-called FF mode during fast forward reproduction. In this state, search can be performed by fast-forward reproduction.

In the FF mode, the pinch roller 50 is not pressed against the capstan 8, that is, a so-called pinch roller off state. T reel and S reel
A speed control signal based on the TFG signal and the SFG signal is supplied from each FG of the reel. The tape 2 is wound around the T reel 31A while being controlled in speed by the rotation of the T reel motor.

The S reel motor controls the back tension by rotating counterclockwise while performing the same running control as in the FWD mode, thereby preventing the tape from becoming loose.

The tension applied to the tape in the operation mode by actually bringing the tape into sliding contact with each part is about 7 to 9 (g) based on the output from the tension pickup 100 due to the pinch-off state. It turns out that it is small. Tape tension control is performed based on the detected value.

Finally, the arrangement and operation relationship shown in FIG. 9 show a so-called REW mode at the time of early winding. In this state, a search is performed by fast-forward reverse playback.

In the REW mode, the pinch roller 32 is not pressed against the capstan 8, that is, the pinch roller is turned off. The S reel motor has a TFG signal,
The arithmetic processing based on the SFG signal is performed by the arithmetic processing circuit 33a, and the result is supplied as a speed control signal. Further, the arithmetic processing circuit 33a supplies the information on the position variation supplied from the tension pickup 100, that is, the feedback correction signal based on the tension detection signal to the S reel motor for control.

The T reel motor also detects the position of the tension pickup 100, and increases or decreases the drive voltage of the T reel motor so that the tension on the entrance side of the S reel 30A becomes constant.

As described above, the tape 2 is pulled and wound on the S reel 30A while giving tension by the rotation drive of the S reel motor. The back tension is controlled by rotating the T-reel motor clockwise to prevent the tape from becoming loose.

The tension applied to the tape in the operation mode by actually bringing the tape into sliding contact with each part is about 14 to 20 based on the output from the tension pickup 100.
(G) It turns out that it is large. Tape tension control is performed based on the detected value.

Conventionally, a plurality of tension pickups have been required to detect the tape tension in such a plurality of operation modes. However, one tension pickup, which is the tension detection device of the present invention, is provided at the entrance side of the drum. Just do it.

In this embodiment, 3.5 inches 8 mm
Although the VTR has been described, the present invention is not limited to this embodiment, and the tape tension can be similarly detected over a wide range by using a general magnetic recording device such as a tape streamer or a digital audio tape recorder. , Tension control based on this detection can be performed.

With the above configuration, the tension detecting device and the tension control device can detect the tension in a plurality of modes with a small number of components.
Space saving and cost reduction of the device can be achieved. Thereby, even if the device is downsized, the function can be maintained without lowering the operation mode. In particular, it is effective when used for products such as 3.5-inch standard height 8 mm tape streamers and 8 mm VTRs.

[0075]

According to the tension detecting device of the present invention, a plurality of modes of tension can be detected with a small number of components, and the space and the cost of the device can be reduced.

Further, according to the tension control device of the present invention, it is possible to detect the tension in a plurality of modes with a small number of components, and it is possible to reduce the space and cost of the device. Thereby, even if the device is downsized, the function can be maintained without lowering the operation mode. In particular, it is effective when used for products such as 3.5-inch standard height 8 mm tape streamers and 8 mm VTRs.

[Brief description of the drawings]

FIG. 1 is a plan view showing a schematic configuration of a tension detection device according to the present invention and a relation between a reference arrangement.

FIG. 2 is a plan view showing an arrangement at the time of minimum tension in the tension detecting device.

FIG. 3 is a plan view showing an arrangement at a maximum tension in the tension detecting device.

FIG. 4 is a graph showing a relationship between a rotation angle of a tension arm and tension in the tension detection device.

FIG. 5 is a graph showing a relationship between a tension and an output voltage from a Hall element in the tension detecting device.

FIG. 6 is a schematic block diagram of a tension control device according to the present invention.

FIG. 7 is a schematic diagram for explaining an FWD mode of a 3.5-inch standard height 8 mm VTR provided with the tension control device.

FIG. 8 is a schematic diagram illustrating an RVS mode of a 3.5-inch standard height 8 mm VTR provided with the tension control device.

FIG. 9 is a schematic diagram illustrating an FF mode of a 3.5-inch standard height 8 mm VTR provided with the tension control device.

FIG. 10 is a schematic diagram for explaining a REW mode of a 3.5-inch standard height 8 mm VTR provided with the tension control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tension detector 10 Rotating shaft 11 Tension arm 12 Guide roller 13 Substrate 14 Magnet 15 Hall element 16 Tension coil spring 11b, 17 Pin 18 Balancer 19, 20 Guide pin 30 S reel motor 31 T reel motor 32 Capstan motor 8 Capstan 30A S reel 31A T reel 50 Pinch roller

Continued on the front page (72) Inventor Mitsunori Sakuma 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Within Sony Corporation (72) Inventor Katsumi Maekawa 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Stock In-company (72) Inventor Masaki Yoshizawa 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (56) References JP-A-6-176435 (JP, A) JP-A-6-195806 (JP) (A) JP-A-4-168649 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 15/093 101 G11B 15/43

Claims (5)

(57) [Claims] 1. A tension detecting device for detecting a tape tension when a tape is run between one reel and the other reel while the tape is wound around an outer peripheral surface side of a drum of a rotary head device and slides on the drum. A rotatable guide roller disposed on one end side for sliding contact with the rotary arm member, the rotary arm member defining a distance between the guide roller and a rotary shaft positioned at the center of rotation, and a rotary shaft of the rotary arm member integrated therewith. A first position detecting means composed of two magnets disposed on a substrate which is rotatably rotated, and a hall element fixedly disposed at a position for detecting a relative rotation amount of the first position detecting means. 2. A tension detecting device comprising: a second position detecting means; and a biasing means for biasing the rotating arm member in a direction in which the tape and the guide roller slide. 2. The distance between the rotating shaft of the rotating arm member and the guide roller is set such that the equilibrium position between the rotational torque caused by the urging force of the urging means and the tape tension is at least ± 15 ° with respect to at least the reference position. 2. The tension detecting device according to claim 1, wherein the rotation distance is set to a predetermined value. 3. A tension detected by rotation of the first position detecting means and the second position detecting means,
2. The tension detecting device according to claim 1, wherein the detection range is set to a range of about 7 to 20 g. 4. The tension detecting device according to claim 1, wherein one is provided between the drum and a supply reel that supplies the tape. 5. A tape drive mechanism using two reel motors for independently driving a reel on a supply side and a reel on a winding side while winding and slidingly contacting the outer peripheral surface side of a drum of a rotary head device. In a tension control device that controls a tape tension by supplying a control signal according to an operation mode to a reel motor, a rotatable guide roller that slides on the tape is provided on one end side.
And a rotating shaft positioned at the center of rotation with the guide roller.
And a tape tension detecting means disposed between the drum and a supply reel for supplying the tape, wherein the tape tension detecting means comprises a rotating arm member.
Two mats arranged on a substrate that rotates integrally with the
A first position detecting means comprising a gnet, and a position for detecting a relative rotation amount of the first position detecting means.
Position detecting means comprising a Hall element fixedly disposed
And a tension detecting device.