JPS6342335B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic tape device with a simplified drive mechanism for a reel stand. More specifically, the present invention relates to a magnetic tape device in which a drive mechanism for a reel stand is simplified. A reel that selectively engages with a reel hub and rotates as a unit in a magnetic tape device that records/plays signals by pulling the tape out of the cassette and running it along a magnetic head installed outside the cassette. This invention relates to an improvement in the drive mechanism of the stand.

Traditionally, in many magnetic tape devices such as cassette-type video tape recorders, an idler installed between the reel stands is connected between the drive shaft and the reel stand as a reel stand driving means, and the recording/playback mode and fast forward mode are controlled. The device was configured to wind up magnetic tape at the same time. However, conventional reel stand driving means require complicated mechanisms such as plungers and switching mechanisms in order to selectively connect the idler between two reel stands. This poses a problem in that the response time required for switching operations is also large, making it difficult to respond to complex movements. In addition, when external vibrations are applied when pulling out a magnetic tape from a cassette, the idler rolls into contact with the reel stand, which increases the rotational load of the roll contact on the reel stand and applies abnormal tension to the magnetic tape being pulled out. However, serious accidents such as damage to the magnetic tape were likely to occur.

The purpose of the present invention is to solve this problem by pulling out the magnetic tape from a cassette containing a pair of reel hubs wound with the magnetic tape to the outside of the cassette and attaching it to a magnetic head installed outside the cassette. A magnetic tape device that records/plays signals by running the tape has a simple mechanism and is configured so that the idler does not come into contact with the reel stand when the tape is pulled out, making it possible to safely and reliably pull out the tape from the cassette. The purpose of the present invention is to provide a magnetic tape device with a high level of functionality.

Next, the configuration and operation of the magnetic tape device of the present invention will be described based on illustrated embodiments. In FIG. 1, a supply reel stand 15 and a take-up reel stand 16 are rotatably loosely fitted to each of reel shafts 13 and 14 set up on a substrate 11.
When the cassette 17 is installed in the main body of the apparatus, it engages with the supply reel hub 18 and the take-up reel hub 19 inside the cassette 17 and rotates integrally. The magnetic tape 20 wound on the supply reel hub 18 is
A pair of notches 3 provided at the front of the cassette 17
It is guided by guide posts 32 and 33 in the cassette 17 so as to cover the front surfaces of the windings 0 and 31, and is wound up on the take-up reel hub 19.

Inside the pair of notches 30 and 31 are guide posts 34 and 3 for pulling out and guiding two magnetic tapes 20 from the cassette 17, respectively.
5, 36, and 37 are arranged. The guide posts 34 and 35 are implanted on a first drawer block 40 that slides while being guided by a first groove 38 on the sub-board 12 that is placed parallel to the board 11. The guide posts 36 and 37 also slide while being guided by the second groove 39 on the sub-board 12. As is well known, the operation and effect of the pair of drawer blocks 40 and 50 installed on the second drawer block 50 is achieved by rotating a lever or transmitting the rotational force of a motor through a group of gears. By moving the pull-out blocks 40, 50 to a predetermined position in the direction of arrow A, the guide post 3
4, 35 and 36, 37 are moved to the position indicated by the dotted line in FIG. 1 and fixed while pulling out the magnetic tape 20. The pulled-out magnetic tape 20 is attached at a predetermined angle to a drum 51 having a rotating head (not shown) therein and to a fixed head 52.

On the other hand, as shown in FIG. 2, a belt 54, a pulley 5
5. A cam 58 having a gear on its outer periphery and driven by a motor 57 via a gear 56 is loosely fitted to be rotatable. As shown in FIGS. 2 to 4, this cam 58 is configured as a positive cam having a groove 59 extending over 360 degrees, and its lift curve is as shown in FIG.゜, 80゜~100゜,
Between 360° and 380°, the cam follower 61 (described later)
seems to be moving. Furthermore, this board 1
A guide shaft 60 is implanted on the back side of the reel shaft 1, and an actuation plate 62 is provided on the actuation plate 62, which has a cam follower 61 that fits into the groove 59 of the cam 58 together with the protruding parts on the back side of the reel shafts 13 and 14. It is guided by loosely fitting into elongated holes 63, 64, and 65.

The clockwise rotation of the motor 57 causes the cam 5 to
8 begins to rotate counterclockwise, the actuating plate 62 does not move at all from 0° to 30°, but from 30° to 50°, the actuating plate 62 moves as shown by the arrow in FIG. Stroke of cam 58 in direction B: 3mm
Move by minutes. This state is a state in which the stop mode shown in FIG. 2 has shifted to the fast forward mode. When the actuating plate 62 moves 3 mm, a switch (not shown) connected to the motor 57 is turned off and the rotation of the motor 57 is stopped. At this time, since the motor 57 has an inertial mass, there is a time delay in stopping, and the cam 58 changes the rotation angle.
Even if the rotation exceeds 50 degrees, as shown in Fig. 6, the lift amount is zero from the rotation angle of 50 degrees to 80 degrees of the cam 58, so the actuating plate 62 does not move and the stroke is accurately 3 mm. Secured.

On the substrate 11, as shown in FIG. 1, a supply side brake 66 and a take-up side brake 67 are loosely fitted to shafts 68, 69 on the substrate 11 so as to be freely rotatable.
A spring 70 is stretched across the brakes 66, 67,
A rotational force is applied in the direction of the supply reel stand 15 and the take-up reel stand 16, respectively. Further, in the supply side brake 66 and the winding side brake 67, pressing pins 71 and 72 are implanted in the direction of the back surface of the substrate 11, respectively. It's growing. Further, the pressing pins 71, 72 pass through openings 76, 75 having cam surfaces 73, 74 provided in the actuating plate 62, as shown in FIG. Therefore, as the actuating plate 62 moves 3 mm in the direction of arrow B in FIG. 75, the supply side brake 66 and take-up side brake 67 are separated from the supply reel stand 15 and take-up reel stand 16, respectively, against the rotational force of the spring 70. This spaced apart condition is shown in FIG.

The actuating plate 62 has a protruding locking portion 81 below an idler support shaft 91 of an idler 90, which will be described later, in FIG. FIG. 5 shows the structure of the idler section, and an idler arm 94 is loosely fitted to a motor shaft 93 of a reel motor 92 attached to the back side of the substrate 11 so as to be freely rotatable. Further, a drive gear 95 is fixed to the reel motor shaft 93 so as to rotate integrally with the reel motor shaft 93, and meshes with a tooth portion 96 formed on the idler 90. The idler 90 is rotatably fitted loosely into an idler support shaft 91 mounted on an idler arm 94, and the felt 90 is rotated by a compression spring 97.
8 to the idler arm 94 to obtain a predetermined rotational slip torque. Therefore, if the reel motor shaft 93 rotates clockwise in FIG.
0 is rotated counterclockwise by the engagement of the tooth portion 96 with the drive gear 95, and at the same time, clockwise rotational force is applied to the idler arm 94, and the idler arm 94 is rotated in the direction of the take-up reel stand 16. Rotate. Conversely, if the reel motor shaft 93 rotates counterclockwise, a counterclockwise rotational force is applied to the idler arm 94 and the supply reel stand 15
rotate in the direction. A capstan 77 rotatably disposed on the substrate 11 is rotated clockwise in FIG. 1 by a capstan motor 79 via a belt 78.

The pinch roller 80 is located near the solid line shown in FIG. 1 except in the recording/reproduction mode, and is moved in the direction of the arrow B in FIG. The pinch roller arm 83, which has a spring 82 stretched between it and the operating plate 62, rotates counterclockwise and moves to the position indicated by the dotted line in FIG.
7 to move the magnetic tape 20 to the right in FIG. In this case, the transferred magnetic tape 20 is wound onto the take-up reel hub 19 by the idler 90 driving the take-up reel stand 16 in rolling contact.

Next, the operation of the magnetic tape device configured as described above will be explained. In the stop mode where the cam rotation angle is 0 degrees, when the record/playback switch (not shown) of the device is pressed, the motor 57 shown in FIG.
9 begins to rotate counterclockwise. The rotation of the motor 57 is controlled by the cam 5 via a belt 54 and a gear 56.
As shown in FIG.
Even when the cam 7 starts rotating, the actuating plate 62 does not start moving immediately, and when the rotation angle of the cam 58 starts to exceed 30 degrees, the cam follower 61 moves in the direction of arrow B in Fig. 2, so the actuating plate 62 moves toward the reel. The cam 58 guided by the shafts 13, 14 and the guide shaft 60 moves 3 mm in the direction B shown in FIG. 2 until the rotation angle reaches 50 degrees, and the cam surface 7
3 and 74 press the pressing pins 71 and 72 set on the supply side brake 66 and the take-up side brake 67, respectively, so that the supply side brake 66 and the take-up side brake 67 are completely connected to the supply reel stand 15 and the take-up reel. It is separated from the stand 16. At this time, the locking portion 81 provided on the actuating plate 62 is located approximately midway between the two reel stands 15 and 16, as shown in FIG.

Further, the motor 57 continues to rotate, but the cam 58
While the rotation angle is from 50° to 80°, the actuating plate 62 does not move as shown in Fig. 6, and the rotation angle is from 80° to 100°, and then the actuating plate 62 is rotated 3 mm further in the direction of arrow B shown in Fig. 2. The locking portion 81 moves to the position shown in FIG. 3, and at the same time, the reel motor 92 starts rotating counterclockwise in FIG. As a result, the idler arm 94, which was rotatable around the motor shaft 93, is given a rotational force in the counterclockwise direction in FIG. As shown in FIG. 3, the idler 90 comes into contact with the locking portion 81 and only rotates to the position shown by the dotted line, that is, the position shown by the solid line in FIG. 1, and does not come into contact with the take-up reel stand 16. Also brakes 66, 6
7 is spaced apart from both reel stands 15 and 16 because the pressing pins 71 and 72 remain on the cam surfaces 73 and 74 as shown in FIG.

After this, the motor 57 continues to rotate, but
For the rotation angle of the cam 58 from 100° to 360°, the operating plate 6
2 does not move and remains in the state shown in FIG.
Although not particularly shown, the pair of drawer blocks 40 and 50 in FIG. 1 are moved in the direction of arrow A from the solid line position in FIG. While moving, the magnetic tape 20 is pulled out by the guide posts 34, 35 and 36, 37 and fixed at a predetermined position indicated by the dotted line in FIG. In the magnetic tape device of the present invention, even during the operation of pulling out the magnetic tape 20, the reel motor 92 continues to rotate in the counterclockwise direction, and the idler 90 is moved between the two reel stands 15 as shown in FIG. ，
It is forcibly held at a position between 16 and 16. As a result, the reel stands 15 and 16 can rotate freely, and there is no fear that excessive tension will be applied to the magnetic tape 20 when the magnetic tape 20 is pulled out. That is, if the idler 90 is able to freely roll onto both reel stands 15 and 16 as in a conventional magnetic tape device, for example, the take-up reel stand 1 in FIG.
6 rotates clockwise when the magnetic tape 20 is pulled out, and if the idler 90 comes into contact with this, the idler 90 will wedge between the take-up reel stand 16 and the drive gear 95. As a result, an excessive braking force is applied to the take-up reel stand 16, and an excessive tension is generated on the magnetic tape 20, resulting in serious damage such as permanent elongation or breakage.

Further, as the cam 58 continues to rotate from a rotation angle of 360° to 380°, the actuating plate 62 moves an additional 3 mm and then stops, resulting in the state shown in FIG. This state is
Since the locking part 81 has moved to the right in FIG. 4 in response to the recording/reproduction mode, the idler support shaft 91
The idler 9 does not come into contact with the locking part 81.
0 is brought into contact with the take-up reel stand 16 by the counterclockwise rotation of the reel motor 92, and the take-up reel stand 16
is rotated counterclockwise in FIG. The pinch roller 80 also moves to the position indicated by the dotted line in FIG.
0 at a predetermined speed. The transferred magnetic tape 20 is wound onto the take-up reel hub 19.

Next, in this recording/reproduction mode, when the stop switch (not shown) of the device is pressed, the motor 57 rotates counterclockwise in FIG.
8 rotates clockwise, and the actuating plate 62 moves to the right at a rotation angle of 380° to 360°. Therefore, the pinch roller 80 is separated from the capstan 77, resulting in the state shown in FIG. 3. At this time, reel motor 9
2 in the clockwise direction, the idler arm 94 is given a clockwise rotational force, and the idler 90 rolls into contact with the supply reel stand 15, contrary to FIG. Start rotating in the direction. At the same time, the motor 57 rotates counterclockwise, and the cam 58 further rotates from a rotation angle of 360°.
Rotates up to 100°. In this case, contrary to the above-described drawing operation of the magnetic tape 20, the pair of drawing blocks 40 and 50 move in the direction of arrow C from the position indicated by the dotted line shown in FIG. 1 to the position indicated by the solid line. be returned. The magnetic tape 20 is reliably wound around the supply reel hub 18 without slack due to the rotation of the supply reel stand 15 described above.

Further, the motor 57 rotates and the cam 58 changes the rotation angle.
When the rotation from 100° to 0° is completed, the device enters the stop mode. In this process, the brakes 66 and 67 are applied to both reel stands 15 and 30 at the rotation angle of the cam 58 from 50° to 30°
16 to ensure that the reel stand 1 is
5 and 16 are in a stopped state.

Next, in the stop mode, when a rapid forward switch (not shown) of the device is pressed, the cam 58 rotates, resulting in the state shown in FIG. 2. At this time, as mentioned above, both brakes 66 and 67 are connected to both reel stands 1.
5 and 16, and the locking portion 81 is located approximately midway between both reel stands 15 and 16. Therefore, if the reel motor 92 is rotated clockwise in FIG. 2, the idler spindle 91 of the idler 90 does not come into contact with the locking portion 81, so that the supply reel stand 15 is rotated as shown by the two-dot chain line in FIG. The reel stand 1 rotates and rotates to supply the magnetic tape 20.
5 and reversely rotate the reel motor 92 counterclockwise in FIG. 2, the magnetic tape 20
is fast-forwarded to the take-up reel stand 16.

As explained above, in the magnetic tape device of the present invention, the magnetic tape is pulled out from the first position inside the cassette to the outside of the cassette, and the second position is attached to the magnetic head located outside the cassette.
When the magnetic tape is pulled out to the position shown in FIG. Since the idler means is positioned stably between the reel stands, it is resistant to external vibrations, and the idler means does not dig into both reel stands while the tape is being pulled out. It is possible to prevent the application of tension, and therefore, it is possible to reliably and stably draw out the magnetic tape without damaging the magnetic tape. During the tape storage operation, even if the locking means is in the same state as when the tape is being pulled out, simply rotating the idler drive shaft in the opposite direction makes it possible to rotate the idler means into contact with the other reel stand. A reel stand drive mechanism can be realized with a simple configuration. Moreover, since the locking means is configured to operate in conjunction with the operating member that switches the operating mode of the magnetic tape device, it engages with each member such as the pinch roller and brake that realizes each operating mode of the magnetic tape device. It is possible to ensure the timing of the operation with the stop means, and to further improve the reliability and safety of the operation of pulling out and storing the magnetic tape. Further, since it is not necessary to move many members to connect and separate the idler means, there is also an effect that the follow-up speed for switching the direction of contact of the idler means is high and the operation is smooth. Moreover, its manufacturing cost is low, and its industrial value is extremely large.

[Brief explanation of drawings]

1 to 6 are views showing embodiments of the magnetic tape device of the present invention, in which FIG. 1 is a top view of the magnetic tape device, and FIG. 2 is a top view of the magnetic tape device in a fast forward mode. 3 is a back view of the magnetic tape device during tape draw-out operation, FIG. 4 is a back view of the magnetic tape device during recording/reproducing mode, and FIG. 5 is a back view of the magnetic tape device of the present invention. FIG. 6, a cross-sectional view of the idler drive mechanism used, is a diagram showing the lift amount of the cam. DESCRIPTION OF SYMBOLS 11... Board, 15... Supply reel stand, 16... Take-up reel stand, 51... Drum, 40, 50... Drawer (block), 57... Motor, 58... Cam, 62...
Operating plate, 77... Capstan, 90... Idler, 91... Idler support shaft, 81... Locking portion.

Claims (1)

[Scope of Claims] 1. Using a reel stand driving means, a magnetic tape is pulled out from a cassette containing a pair of reel hubs wound with magnetic tape to the outside of the cassette and attached to a magnetic head installed outside the cassette. A magnetic tape device that records/reproduces signals by running a magnetic tape device includes: a pair of reel stands that respectively engage with and rotate integrally with a pair of reel hubs in the cassette; and a pair of reel stands that are located between the reel stands and are rotatable in forward and reverse directions. an idler means located between a drive shaft and the reel stand, the idler means being configured to be rotatable about the drive shaft and capable of selectively rolling into contact with the pair of reel stands; a rotational force applying means for applying a rotational force by rotation of a shaft and selectively rolling the idler means into contact with one of the pair of reel stands according to the rotational direction of the drive shaft; a locking means for preventing the provided idler means from rolling into contact with the reel stand as necessary, and pulling the magnetic tape out of the cassette from a first position within the cassette; When pulling out the magnetic tape to bring it to the second position where it is attached to the magnetic head, by rotating the drive shaft in one direction,
A magnetic tape device characterized in that the idler means is prevented from rolling into contact with the reel stand by applying rotational force to the idler means in the direction of one reel stand and bringing the idler means into contact with the locking means. 2. When the magnetic tape is pulled out from the first position to the second position, the drive shaft is rotated in one direction, and the idler means is brought into contact with one of the pair of reel stands. The second magnetic tape is blocked by the locking means.
When storing the tape from the position to the first position, the drive shaft is rotated in the other direction, and the idler means is brought into contact with the other of the pair of reel stands. A magnetic tape device according to claim 1. 3 The above-mentioned locking means is used for recording/recording of the above-mentioned magnetic tape device.
Claims characterized in that the magnetic tape device is configured to operate in conjunction with the operation of an operating member that moves to a plurality of positions corresponding to operation modes of playback, stop, and fast winding, and switches the operation mode of the magnetic tape device. 1st
The magnetic tape device according to any one of Items 1 and 2. 4. The magnetic tape device according to claim 3, wherein the operating member moves following a cam that is rotationally driven by a motor.