JPS5911976B2 - magnetic recording and reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a magnetic recording/reproducing apparatus having a novel configuration for driving a tape without using a pinch roller.

Conventionally, in magnetic recording and reproducing devices, the tape is generally driven during recording and reproduction by pressing the tape against the capstan using a pinch roller. Since it is made of an elastic material such as rubber, the deformation caused by pressure contact with the capstan has a subtle effect on the running of the tape, and has a particularly large effect on wow and flutter.

In other words, after the pinch roller is molded, its outer peripheral surface is polished to improve its accuracy, but in this case, it is difficult to maintain a high level of polishing accuracy due to its elasticity, and uneven hardness occurs, making it difficult to achieve uniform crimping. In addition, since the pinch roller is normally attached to a bearing that is rotatably supported by the pinch roller shaft, variations in thickness occur due to eccentricity at that time, which worsens wow and flutter during tape running. This was a major cause.
H5 The present invention is designed to eliminate such conventional drawbacks, and one embodiment thereof will be described below with reference to the drawings. Reference numeral 1 denotes a main body of the apparatus, and reel stands 4 and 5 are disposed on the left and right sides of the front surface of the main body 1, and reel stands 4 and 5 are provided integrally with reel shafts 2 and 3, respectively.
The shafts of the motors 6 and T provided therein are integrated with the reel shafts 2 and 3 and are directly connected to the motors.

A capstan 8 is arranged at the central lower blade of the main body 1,
Further, in the front surface 35 of the main body 1 at the lower part of the capstan 8, elongated holes 9 and 10 are formed in the left and right directions so as to be symmetrical with respect to the perpendicular line Al passing through the center of the capstan 8. , 10 have tape guides 11, 1 on both sides.
2 is provided. On the perpendicular line A of the upper blade of the capstan 8 is a tape guide 13 consisting of a pin, etc.
Further, a recording head 14 and a reproducing head 15 are provided on both sides of the tape guide 13 in symmetrical positions with respect to the perpendicular line A, and the heads 14 and 15 are protected by a head cover 16. In addition, the long hole 9
, 10 are provided with guide rollers 17 and 18 movable along the elongated holes, and an erasing head 19 is provided between the tape guide 11 and the guide roller 17, and the erasing head 19 is covered with a head cover. 120. As shown in FIG. 3, the guide rollers 17 and 18 are rotatably supported by shafts 23 and 24 at the lower ends of rotating levers 21 and 22 formed in a substantially L shape. , 22 are both rotatably supported by a pin 26 on a slide lever 25 that can slide vertically. Arms 27 and 28 are integrally formed on the left and right sides of the slide lever 25, and elongated holes 29 and 30 formed in the arms 27 and 28 are provided with pins fixed to the rotary levers 22 and 21. 31 and 32 are fitted. The erasing head 19 is mounted on a rotary lever 21 in the vicinity of the guide roller 17, and is adapted to move left and right as the rotary lever 21 rotates.

The rotating levers 21 and 22 are operated by springs 33 and 34, respectively, so that the lower ends of the levers 21 and 22 are forced to separate from each other, that is, the guide roller 17
, 18 are urged in the direction of force to separate them, and as a result, the slide lever 25 is also urged against the lower blade by pins 31 and 32, and the rod 37 of a plunger 36 connected to this slide lever 25 with a pin 35 is in a pulled out state when it is not energized.

Note that the tape guide 13 is attached to the lower end of the slide lever 25. The plunger 36 is configured to be energized by a regeneration operation.
6 is energized, the slide lever 25 moves to the upper blade together with the rod 37, which causes the pin 31,
32 is pushed up, the rotation levers 21 and 22 are moved by the spring 3
3 and 34, they are rotated in the direction of force so that they approach each other as shown in FIG. Then, the guide roller 17,
18 are guided by the elongated holes 9 and 10 on the front surface of the main body 1 and come close to each other, and the erasing head 19 is also moved toward the center.Furthermore, by sliding the slide lever 25 to the upper side, the tape guide 13 is also moved to the upper side. This state is maintained as long as the plunger 36 is energized. Of course, it is also possible to cut off the power to the plunger 36 by mechanically holding it with a separate holding mechanism. Next, the rotational drive configuration of the capstan 8 will be explained with reference to FIG.
The capstan shaft 38 is rotatably supported by a housing 39 constituting a capstan motor 40 by bearings 41a and 41b.

A disc-shaped pulley 42 made of a magnetic material such as iron is fixed to the capstan shaft 38, and a predetermined number of teeth 43 are formed on the outer periphery of the pulley 42. A rotation speed detection section 44 that generates a voltage with a frequency proportional to the rotation speed of the pulley 42 is provided at the position where the rotation speed of the pulley 42 is proportional to the rotation speed. That is, the housing 39 is provided with a coil 46 wound around a core 45, and when the coil 46 is energized, the core 45 and the pulley 42 are configured to receive magnetic force. 42 is rotated integrally with the capstan 2, the rotation speed detection unit 44 detects the magnetic force from the teeth 43 of the pulley 42,
For one revolution of the capstan 8, an AC output with a frequency equal to the number of teeth 43 is generated. First, a rotor 48 made of a magnetic material having a recess 47 at the lower part is fitted and supported on the capstan shaft 38 by the lower blade of the pulley 42 so as to be movable up and down and rotatable independently with respect to the capstan shaft 38. The rotor 48 is biased downward by a spring 49 interposed between the rotor 48 and the pulley 42, and is brought into contact with a locking portion 50 fixed to the lower end of the capstan shaft 38.

A magnet 51 is provided on the inner circumference of the recess 47 of the rotor 48.
is attached, and the stator core 52 attached to the housing 39 and its coil 53 are arranged in the internal force of the magnet 51. The stator coil 53 is configured to be energized when power is supplied to the device, that is, when the power switch is turned on, and as a result, a rotating magnetic field is generated in the stator core 52, and the magnet 5
1 rotates together with the rotor 48. This rotation of the rotor 48 is not transmitted to the pulley 42 and the capstan 8 because the spring 49 slips at the contact portion with respect to the pulley 42, and the capstan 8 is not rotated even when the rotor 48 rotates. In this case, if the spring 49 cannot completely block the transmission of rotational force, the pulley 1J42 may be braked to prevent it from following rotation. When the power switch is turned on and a regeneration operation is performed while the rotor 48 is rotating, the coil 46 is energized and the coil 46 is magnetized, so that the rotor 4
8 is attracted to the upper blade and moves against the elastic force of the spring 49, and the upper surface of the rotor 48 comes into pressure contact with the friction plate 54 provided on the lower surface of the pulley 42, whereby the pulley 1J42 The capstan 8 is also rotated together with the capstan 8.

Of course, if the pulley 42 is braked, the brake is released at the same time as the coil 42 is energized. When the core 46 is energized, the cap nut 8 is driven to rotate, and at the same time, the pulley 1 42 is magnetized, causing it to rotate, so that the teeth 43 formed on its outer periphery sequentially pass through the rotational speed detection section 44. As a result, a voltage with a frequency proportional to the rotation speed of the pulley 42, that is, the cap nut 8, is generated in the detection section 44, and by controlling the rotation of the rotor 48 using the output, the rotation speed of the cap nut 8 is kept constant. The rotation speed is maintained. FIG. 6 shows an electric circuit in which a power switch 56 and a nutator coil 53 are connected in series to a power source 55, and a series circuit of a switch 57 and a coil 46, which are closed by a regeneration operation, is connected to the power source 55 via a power switch 56. and a plunger 36 in parallel with the coil 46.
is connected.

With the above configuration, in the stopped state (power switch not turned on), the motors 6 and 7 are stopped, and the motor that rotates the cap nut 8 is also stopped. The guide rollers 17 and 18 are located apart from each other as shown in FIGS. 1 and 3, and the erasing head 19 is also moved to the left. Further, the tape guide 13 is in a state of being moved to the lower blade. In this state, both reel stands 4
, 5 are equipped with reels 58 and 59 as shown in FIG.
The tape 60 is transferred from the reel 58 on the supply side to the tape guide 11.
The tape is wound onto the reel 58 on the winding side through the lower blade of the tape guide 17, the guide roller 17, the left side of the capstan 8, the upper side of the tape guide 13, the right side of the capstan 8, the guide roller 18, and the lower blade of the tape guide 12.

With the tape 60 mounted in this manner, the tape between the tape guide 11 and the guide roller 17 is located at the lower blade than the front surface of the erasing head 19, as shown in FIGS. 2 and 7. Although it is lifted by the tape guide 13 at the upper blade of the capstan 8, it is located at the lower blade of the recording head 14 and playback head 15 and is away from these heads. After attaching this tape 60 or turning on the power switch 56 in front of the device, the motor 40 for the capstan 8
The rotor 48 rotates, but the capstan 8 is still in a stopped state. Next, for example, when a stop operation or a playback preparatory operation is performed, the motors 6 and 7 for driving the reel stand are energized, and the motor 6 is rotated in the clockwise direction, and the motor is in the clockwise direction. 7 is also driven with a weak driving force in the counterclockwise direction, and the tape 60 is pulled in mutually opposite directions. In this case, the torques of the motors 6 and 7 in opposite directions are set so that the tension on the tape supply side and the tape tension on the tape winding side are the same or almost the same, or the torque of the motors themselves is set to be approximately the same. Capstan 8 of tape 60 set to be identical
The tape 60 is set so as not to be moved in any direction of force due to contact friction with the tape guides 11, 12, 13, guide rollers 17, 18, etc.

Here, when the regeneration operation is performed and the switch 57 is closed, the coil 46 of the motor 40 is energized, so the capstan 8 is driven to rotate, and the rotation speed of the capstan 8 is kept constant by the output of the rotation speed detection section 44. At the same time, the plunger 36 operates and the slide lever 25 moves upward, causing the tape guide 13 to further lift the tape 60 and bring the tape 60 into contact with the recording head 14 and playback head 15. The guide rollers 17 and 18 are moved closer to each other, and the eighth
As shown in the figure, the tape 60 is wrapped approximately once to the lower edge of the capnut tongue 8 to increase the contact angle.

As the guide roller 17 moves, the erasing head 19 also moves, and the movement is arcuate, so that the erasing head 19
The front side of is contacted with tape 60.

Due to the rotation of the capstan 8, the tape 60, which had been stopped until then, runs in the rotation direction of the capstan 8,
It runs at the same speed as the circumferential speed of the capstan 8 to perform a reproduction or recording operation. Furthermore, if the stop operation is performed, the power to the coil 46 and plunger 36 is cut off, so the rotation to the cap nut 8 is cut off, and the guide rollers 17, 18, tape guide 13 and erasing head 19 are returned to their original state when stopped. When the tape 60 returns to its position, it leaves the recording head, playback head, and erase head. Next, tape fast-forwarding and rewinding operations are performed by energizing the motor 6 or motor 7. In this case, for example, during tape fast-forwarding, the motor 7 is driven clockwise;
The motor 6 on the winding side may be rotated with a weak torque in the direction in which the tape 60 is supplied, that is, in the counterclockwise direction, so that the start-up of the fast-forwarding operation can be smoothly performed.

In addition, at the start of the regeneration operation, since the rotor of the rotation motor 40 of the cap nut 8 is rotated before the regeneration operation, the pulley 1J42 and the rotor are rotated so that the rotational force is transmitted to the pulley 42. When combined with the rotor 48,
The capstan 8 immediately shifts to constant speed rotation.

This is because the mass of the rotor 48 and the magnet 51 attached to it is usually large, and if the rotor 48 is rotated at the same time as the tape 60 starts running, it will take time to shift to constant speed rotation, and the start-up of the playback or recording operation will be delayed. However, by rotating the rotor 48, which has a large mass, in advance, and connecting the capstan 8, which has a relatively light mass, to the rotor 48 during the tape running operation, the tape 60 can start running in a short time. Thus, a smooth tape running start operation is performed. In the above embodiment, the plunger 36 is operated by the reproducing operation, but it is operated at the same time as the reel motors 6 and 7 are driven to rotate, and the tape 60 is run when the capstan 8 starts rotating. The tape may have been previously contacted to each head.

With this configuration, the unstable state caused by the tape contacting the head at the start of tape running can be eliminated. As described above, the present invention provides a reel stand for supply and winding, one capnut provided in the middle part of the reel stand, and a capnut in the vicinity of the capstan at a line-symmetrical position with respect to a perpendicular line passing through the center of the capstan. first and second tape guide members provided so as to be movable close to each other in the capstan, and a third tape guide member provided movable on the perpendicular line on the opposite side of the capstan from the first and second tape guide members. a tape guide member, two heads disposed on both sides of the third tape guide member, and a first moving means for moving the first and second tape guide members in a direction closer to each other in conjunction with a playback operation. and a second tape guide member for moving the third tape guide member away from the capstan.
the tape is mounted in contact with the first tape guide member, one side of the capstan with respect to the perpendicular line, the third tape guide member, the other side of the capstan, and the second tape guide member; During the playback operation, the first, second, and third tape guide members are moved to bring the tape into contact with the head, and the capstan is rotated with the tape being wound approximately once around the outer periphery of the capstan. According to the present invention, the tape is attached to the capstan at a constant speed.
The tape is wound and smoothly runs at a constant rate following the rotation of the capstan, allowing recording and reproducing operations to be performed without the need for pinch rollers.

Moreover, since the area of the tape that is in contact with the capstan is separated and comes into contact with the head is extremely small, there is little wow and flutter, and modulation noise due to longitudinal vibration of the tape is also extremely low. Industrial efficiency is great.

[Brief explanation of the drawing]

Fig. 1 is a front view showing one embodiment of the present invention, Fig. 2 is a front view of the tape in the attached state, Fig. 3 is a front view showing the control mechanism of the tape guide, and Fig. 4 is the same operating state. Front view, 5th
6 is a partially sectional side view of the capstan and its motor section, FIG. 6 is an electric circuit diagram, FIG. 7 is a front view of the capstan section with tape attached, and FIG. 8 is a front view of the same tape running state. 4, 5... Reel stand, 8... Cap nut tongue, 13... Tape guide, 14...
Sound head, 15... Playback head, 17, 18
...Guide roller, 19 ... Erasing head, 40 ... Motor.

Claims (1)

[Claims] 1. A reel stand for supply and winding, a capstan provided in the middle of the reel stand, and movable in close proximity to each other in the vicinity of the capstan in a line-symmetrical position with respect to a perpendicular line passing through the center of the capstan. a third tape guide member provided so as to be movable on the perpendicular line on the opposite side of the capstan from the first and second tape guide members; 2 placed on both sides of the third tape guide member.
a first moving means for moving the first and second tape guide members in a direction closer to each other in conjunction with the playback operation, and a second moving means for moving the third tape guide member in a direction away from the capstan. The tape is mounted in contact with one side of the capstan with respect to the perpendicular line from the first tape guide member, the third tape guide member, the other side of the capstan, and the second tape guide member, and is played. During operation, the tape is brought into contact with the head by the movement of the first, second, and third tape guide members, and the tape is wound approximately once around the outer periphery of the capstan, and the tape is rotated at a constant speed by the rotation of the capstan. A magnetic recording/reproducing device characterized in that it is configured to run.