JPH044668B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention involves pulling out a magnetic tape outside the cassette from a cassette containing a pair of reel hubs on which the magnetic tape can be wound, and causing the tape to run along a rotating magnetic head drum installed outside the cassette. The present invention relates to magnetic tape devices such as video tape recorders that record or reproduce signals.

Generally, in a magnetic tape device such as a cassette-type video tape recorder, in a recording mode, the magnetic tape is pulled out and wound around a rotating magnetic head or a fixed magnetic head for audio at a predetermined angle for running, but in a stationary mode, the magnetic tape is inserted into a cassette. There are many ways to store them. In such a magnetic tape device, when recording is temporarily interrupted during signal recording, the magnetic tape is generally wound around the rotating magnetic head drum at a predetermined angle and the running of the magnetic tape is stopped, which is the so-called recording pause mode. It is provided separately from the stop mode. If the operating mode of the device is changed from the recording mode to the recording pause mode, the next time the device is switched to the recording mode again, too many recording joints overlap and the previously recorded portion becomes large. The magnetic tape is run slightly in the opposite direction in order to prevent erasure, the formation of no-signal areas at the joints, so-called gap areas, or disturbances in the signals at the joints. Then, when the recording mode is entered, the running of the magnetic tape becomes stable and the length of the running magnetic tape is corrected until the signal is stably recorded.

However, in this recording pause mode, when the next recording mode is entered, the rotating magnetic head and the capstan that run the magnetic tape at a constant speed remain in a rotating state to enable instantaneous recording, and the signal Generally, power is still being supplied to the processing circuits of the magnetic tape devices, so some users of such magnetic tape devices may interrupt the recording operation to save power. Occasionally, the mode is changed to a stop mode instead of a temporary stop mode. However, when the magnetic tape that has been pulled out during the transition from the recording mode to the stop mode is stored in a cassette, an extremely large amount of the magnetic tape is wound up on the reel hub on the side where the tape is wound, and the next transition to the recording mode occurs. When starting recording, a large portion of the previously recorded portion may be erased, or there may be gaps. To solve this problem, some machines apply a brake force to prevent the reel hub on the side that sends out the magnetic tape from rotating when the magnetic tape is pulled out and stored in a cassette. Abnormal tension is likely to occur on the magnetic tape due to the winding force used to take and store it, and this can cause serious damage to the magnetic tape, especially when magnetic tapes become thinner due to the tendency for recent magnetic tape devices to record/play back for long periods of time. A problem has arisen in providing .

The present invention can solve the above problems, and provides a magnetic tape device that prevents erasing of signals more than necessary even when recording is interrupted via a stop mode, and furthermore does not damage the magnetic tape. It is.

Hereinafter, the present invention will be explained based on illustrated embodiments. 1 and 3 show top views of this embodiment.
In the figure, a take-up reel stand 10 and a supply reel stand 12, which are rotatably loosely fitted to shafts 4 and 6 installed on the upper surface of a substrate 2, are arranged so that when a cassette 20 is installed at a predetermined location on the main body of the apparatus, the cassette each engages with the take-up reel hub 14 and the supply reel hub 16 in 20,
Both reel stands 10 and 12 can be rotated integrally by claws 8 provided thereon. FIG. 2 shows a sectional view of the reel stand drive system, and the take-up reel stand 10 and the supply reel stand 12 have reel gears 30 and 40, respectively, and the reel gears 30 and 40 are planted on the substrate 2. Axis 5
0 and 60, which are rotatably fitted loosely into the take-up reel idler gear unit 52 and the supply reel idler gear unit 62, respectively, and are driven to rotate.
The take-up reel idler gear unit 52 and the supply reel idler gear unit 62 each have a take-up reel idler gear 54, as shown in FIG.
The rotation of the supply reel idler gear a and the supply reel idler gear 64a is transmitted to the take-up reel idler gear 54b, which meshes with the reel gears 30 and 40, and the supply reel idler gear 64b, through clutch means using friction members such as felts 56 and 66. It has a structure that allows for

On the other hand, the capstan 72, which is rotatably supported by a bearing member 70 fixed to the substrate 2, has a rotating roller part 74 in a part thereof, and is pressed against the rotating roller part 74 by applying a predetermined pressing force. main eye 76
The rotation is transmitted to. The main idler 76 has a belt 84 stretched between a pulley portion 78 that is integrally constructed and a relay roller 82 that is rotatably loosely fitted to a shaft 80 that is axially oriented on the base plate 2. 82. A rotary arm 88 having a rotatable idler gear 86 supported at one end is loosely fitted to the shaft 80, and the rotary arm is arranged so that a multi-pole magnetized magnet 90 on the outer periphery is substantially concentric with the shaft 80. 88. Further, on the inner periphery of the relay roller 82, a magnetic material 92 having a magnetic hysteresis characteristic is arranged so as to face the magnet 90 with a predetermined clearance.
is fixed, generates a predetermined attraction force between it and the magnet 90, and applies a rotational force to the rotating arm 88 in the same direction as the rotational direction of the relay roller 82. Further, the idler gear 86 is constantly connected to the relay roller 82.
The relay roller 82 is configured to mesh with a gear portion 94 provided in the relay roller 82 depending on the operation mode of the device.
The take-up reel idler gear 54 is rotated by rotation of the take-up reel idler gear 54.
a or the supply reel idler gear 64a to selectively transmit the rotation of the capstan 72 to the take-up reel stand 10 or the supply reel stand 12 depending on the direction of rotation.

A pinch roller lever 22 is rotatably fitted loosely onto a shaft 18 that is set up on the substrate 2, and a pinch roller 192 is rotatably supported on a shaft 24 that is set up at one end of the pinch roller lever 22. ing. A crimping lever 32 with an elongated hole 28 is loosely fitted onto a shaft 26 that is rotatable and slidable in the longitudinal direction, and a pin 3 that is set on one end of the lever 32 is loosely fitted onto the shaft 26 that is set on the base plate 2.
A connecting arm 36 is rotatably fitted into the pin 4, and the other end of the connecting arm 36 is rotatably fitted into a pin 38 set up on the other end of the pinch roller lever 22. A spring hook 42 is formed at the other end of the crimp lever 32, and a tension spring 44 is stretched between the shaft 26 and the spring hook 42 to hold the crimp lever 32 as shown in FIG. direction, and the end of the elongated hole 28 and the shaft 26 are in contact with each other. That is, the pinch roller lever 22, the connecting arm 36, and the pressure lever 32 constitute a so-called toggle mechanism. Further, at the other end of the crimp lever 32, a pin 46 is configured to pass through a hole (not shown) provided in the substrate 2, extend toward the rear surface of the device, and come into contact with a bent portion 21 provided in a main rod 48, which will be described later. There is. Therefore, when the main rod 48, which will be described later in FIG. 1, moves to the left,
Since the bent portion 21 is in contact with the pin 46, the pressure lever 32 is rotated clockwise, and the pinch roller lever 22 is rotated counterclockwise until the pinch roller 192 comes into contact with the capstan 72. Although the pinch roller lever 22 is not rotated after that,
As the crimp lever 32 continues to rotate clockwise, the crimp lever 32 is guided by the elongated hole 28 and moves downward in FIG. It is crimped onto the capstan 72 with a crimping force of .

In the recording mode, as shown in FIG. 3, the magnetic tape 180 wound on the supply reel hub 16 is moved to the tape drawer member 18 with guide posts 23, 25 and 27, 29 set up from the front surface of the cassette 20.
2 and 183 are guided by guide grooves 31 and 33, respectively, and moved to fixed members 184 and 185 to be pulled out, and a rotating magnetic head drum 186 containing a rotating magnetic head and a fixed head 188 for recording/reproducing audio signals are pulled out. and attached to a tape guide 190 fixed to the substrate 2. Further, since the capstan 72 rotates clockwise in FIG. 3, the main idler 76 rotates counterclockwise in FIG. 3, and the belt 84 and relay roller 82 also rotate counterclockwise in FIG. 3. Therefore, the rotating arm 88 is given a rotational force in the counterclockwise direction in FIG. 3 about the shaft 80, and the idler gear 86 rotating clockwise in FIG.
a, the take-up reel stand 10 rotates clockwise via the clutch means described above, and the pinch roller 192 and capstan 72 work together to transfer the magnetic tape 180 fed at a constant speed to the take-up reel hub without slack. Wind it to 14.

In addition, shafts 110, 120 planted on the surface of the device
A take-up side brake 112 and a supply side brake 122 are respectively rotatably fitted loosely into the take-up reel, and are urged to rotate clockwise and counterclockwise in FIG. 1 by tension springs 114 and 124, respectively. A pressing force is applied to the stand 10 and the supply reel stand 12. In addition, holes (not shown) are made in the board 2 for the take-up side brake 112 and the supply side brake 122.
Tight pin 11 extending to the back of the device through
8,128 is planted, and the lock pin 118,1
The movement of the take-up side brake 112 and the supply side brake 122 is controlled by the engagement and disengagement between the sub rod 130 and the lock lever 43, which will be described later.

On the other hand, a driving gear 160 driven by a motor (not shown) is disposed on the back surface of the substrate 2 shown in FIGS. The sub-cam 142 is rotatably loosely fitted onto the shaft 156. The sub cam 14
2 is a positive cam having a groove 144 spanning 300° as shown in Fig. 9, and its lift curve is such that the cam follower 146 moves only in the section where the lift amount changes as shown in Fig. 9. . Further, the rotating shaft 4 of the take-up reel stand 10 extending from the front surface to the back surface of the substrate 2, the rotating shaft 50 of the take-up reel idler gear unit 52, the guide shaft 132 planted on the back surface of the substrate 2, and the sub-cam 142. rotation axis 15
6 includes a sub rod 130 having a cam follower 146 that engages with the groove 144 of the sub cam 142.
The guide grooves 45, 4 provided in the sub-rod 130
7, 49, and 51 so as to be freely movable back and forth.

Further, the sub-cam 142 is rotatably loosely fitted onto a shaft 164 mounted on the base plate 2 and meshes with a main cam 162 having a gear on its outer periphery, so that the main cam 162 rotates in synchronization with the sub-cam 142 at the same angle. As shown in FIG. 9, the cam is a positive cam having a groove 166 extending over 360 degrees, and its lift curve is as shown in FIG. 9. As shown in FIG.
65 is made to move. Further, a main rod 48 having a cam follower 165 that engages with a groove 166 of the main cam 162 is provided on the shafts 4, 50, 132 to which the sub-rod 130 is loosely fitted and the rotating shaft 164 of the main cam 162. Guide grooves 35, 37, 39, 4
1 and overlaps the sub-rod 130, and is loosely fitted so as to be movable back and forth.

A hole 53 is bored in the sub-rod 130, and an end surface 72 of the sub-rod 130 is adapted to be able to engage with a lock pin 128 of the supply brake 122. Furthermore, a lock lever 43 having a groove 57 wider than the outer diameter of a pin 67 installed in a cam lever 63 (described later) is rotatably fitted into the shaft 55 installed in the sub-rod 130, as shown in FIG. As shown in FIG. 2, the tightening lever 43 has a tightening surface 59 that can engage with the tightening pin 118 of the take-up side brake 112.

Further, a shaft 61 is mounted on the main rod 48, and a cam lever 63 is loosely fitted therein so as to be freely rotatable. The cam lever 63 is provided with a groove 65 that can engage with the shaft 50 set on the base plate 2 as shown in FIGS.
A pin 67 that engages with the groove 57 of No. 3 is planted. The groove 65 allows the tightening lever 43 to be aligned with the shaft 6 according to the left and right movement of the main rod 48 in FIG.
It is a positive cam that rotates around 1.
Further, the main rod 48 is provided with the bent portion 21 and the pin 4 provided at the other end of the crimp lever 32.
It is arranged so that it is in contact with 6.

Although detailed explanation will be omitted since this can be realized by well-known means, the tape pull-out members 182 and 183 are configured to move in accordance with the rotation of the main cam 162, and as shown in FIG. The tape pull-out members 182 and 183 are moved in a clockwise rotation angle range from 40° to 180° from the stopped state shown in FIG. 5 of 162 in FIG.

Now, from the stop state shown in FIG. 5, the sub cam 142
is rotated counterclockwise by a rotation angle of 40° in Figure 5,
The sub-rod 130 is driven by the groove 144 and moves 3 mm to the right in FIG. 5, pushing the kick pin 128. Therefore, the supply brake 122 rotates clockwise in FIG. 1 about the shaft 120 to release the braking force on the supply reel stand 12. on the other hand,
The lock lever 43, which moves together with the sub-rod 130, also moves 3 mm to the right, but as shown in FIG. 9, the clockwise rotation angle of the main cam 162 in FIG.
When rotated by 40 degrees, the main rod 48 does not move and maintains the position shown in FIG. 5, and therefore the cam lever 63 remains in the state shown in FIG. The upright pin 67 does not abut, and the tightening lever 43 is in a freely rotatable state, so the tightening surface 59 does not touch the tightening pin 11.
8 cannot be pressed, and therefore the take-up side brake 112 does not release the braking force on the take-up reel stand 10.

Subsequently, when the sub-cam 142 rotates to a rotation angle of 65 degrees, the position of the sub-rod 130 does not change as shown in FIG. 9, but the main rod 48 moves 1.5 mm to the right in FIG. 5, resulting in the state shown in FIG. 6. becomes.
Therefore, the cam lever 63 is also moved 1.5mm to the right.
As it moves, the cam lever 63 slightly rotates counterclockwise about the shaft 61 as shown in FIG. 6 due to the engagement relationship between the groove 65 and the shaft 50. However, since the pin 67 of the cam lever 63 is located in the recess provided in the groove side surface 69 of the tightening lever 43 shown in FIG.
18 cannot be pressed, and the take-up side brake 112 is
As shown in the figure, it is in a state where it is pressed against the take-up reel stand 10. On the other hand, as mentioned above, the main cam 16
2, the tape pull-out members 182, 18
3 starts moving and smoothly pulls out the magnetic tape 180 from the supply reel hub 16 whose brake force has been released. Further, the pin 46 pressed against the bent portion 21 of the main rod 48 also moves to the right in FIG.
Move in the direction of.

Next, the sub cam 142 and the main cam 162
When rotated from 65° to 95°, main rod 48 does not move as shown in Figure 9, but sub rod 1
30 further moves to the right by approximately 1 mm, resulting in the state shown in FIG. At this time, the tightening lever 43 also moves about 1 mm to the right, so the pin 67 of the cam lever 63 presses the groove side surface 69 of the tightening lever 43, and the tightening lever 43 starts rotating counterclockwise around the shaft 55 in FIG. , the tightening surface 59 presses against the tightening pin 118. Therefore, the take-up side brake 112 rotates counterclockwise in FIG. 4 to release the braking force on the take-up reel stand 10. At this time, the tape pull-out members 182 and 183 are in a state (not shown) in which the magnetic tape 180 is pulled out further than in FIG. Although the wrapping angle of the magnetic tape 180 has also increased,
Further, the braking force of the take-up reel stand 10 is released, and the magnetic tape 180 can be pulled out from the take-up reel hub 14 without applying excessive tension to the magnetic tape 180.

Thereafter, the sub cam 142 and the main cam 162 continue to rotate up to a rotation angle of 205 degrees as shown in FIG. As shown in FIG. 4, the rotation is further counterclockwise, and the pin 67 presses and rotates the tightening lever, so that the take-up side brake 112 and the supply side brake 122 are spaced apart from the take-up reel stand 10 and the supply reel stand 12, respectively. maintain.
In addition, as shown in FIG. 3, the guide posts 23, 2
7 is fixed to the fixing members 184 and 185, and the magnetic tape 180 completes the predetermined attachment to the rotating magnetic head drum 186 and the audio fixed head 188.
The pinch roller 192 is also pressed against the capstan 72 by the movement of the main rod 48. At this time, the capstan 72 rotates clockwise in FIG.
Wind it to 4.

Next, the operation of storing the pulled-out magnetic tape 180 into the cassette 20, which is the main point of the present invention, will be explained.

When a stop button (not shown) is pressed in the recording mode shown in FIG. 3, the drive gear 160 driven by the motor rotates counterclockwise in FIG. 7, causing the sub cam 142 and main cam 162 to rotate clockwise and Rotate counterclockwise. When rotated from a rotation angle of 205 DEG to 180 DEG as shown in FIG. 9, the pinch roller 192 is separated from the capstan 72 due to the movement of the main rod 48 to the right in FIG.
Further, the tape pull-out members 182 and 183 are separated from the fixing members 184 and 185 and begin to move toward the cassette 20. On the other hand, the capstan 72
Start the reverse rotation in the counterclockwise direction in the figure, and rotate the rotating arm 88.
rotates clockwise, the idler gear 86 meshes with the supply reel idler gear 64a, rotates the supply reel stand 12 counterclockwise via the clutch means, and even if the tape pull-out members 182, 183 move. The magnetic tape 180 is wound around the supply reel hub 14 without slack. At this time, the take-up side brake 112 is separated from the take-up reel stand 10, but the magnetic tape 180 is attached to the rotating magnetic head drum 186, the guide posts 23, 25, 27, 2
9 is large, and the friction loss of the magnetic tape 180 is also large. As shown near C in FIG. It's just the slack, and the amount is small.

Next, the state when the sub cam 142 and the main cam 162 are rotated from a rotation angle of 95 degrees to around 65 degrees is shown in FIG. 4, and the moving positions of the tape pull-out members 182 and 183 at this time are shown in FIG. When there is no braking force applied to the take-up reel stand 10 in the vicinity of point B, the magnetic tape 180 is almost unwound around the rotating magnetic head drum 186, and the friction loss of the magnetic tape 180 is reduced. As shown by the solid line in the figure, there was a tendency that not only the slack due to the movement of the tape pull-out members 182 and 183 but also the magnetic tape 180 that had been wound around the take-up reel hub 14 was wound onto the supply reel hub 16 to a large extent. . However, in this embodiment, in the vicinity of B in FIG. 10, that is, in the vicinity of the rotation angle of 65 degrees to 95 degrees of the main cam 162 and sub cam 142, the take-up side brake 112 is moved to the take-up reel stand 10 by the cooperation of the hard lever 43 and the cam lever 63. makes contact and applies braking force. Therefore, from the take-up reel hub 14 to the supply reel hub 1
6, the magnetic tape 180 is not wound, and the amount of winding decreases as shown by the dotted line in FIG. Further, as described above, since the winding angle of the magnetic tape 180 around the rotating magnetic head drum 186 or the guide posts 23, 25, 27, 29 is small, the winding angle is determined by applying a braking force to the take-up reel stand 10 and using the clutch means. Magnetic tape 180
No damage is caused to the magnetic tape 180 even when the magnetic tape 180 is wound.

When the sub cam 142 and the main cam 162 further rotate to a rotation angle of 40 degrees, the tape pulling member 18
2, 183 completely returns to the stop position shown in FIG. 1, and as the sub cam 142 continues to rotate, the sub rod 130 moves to the left in FIG. However, the supply side brake 122 is also press-fitted to the supply reel stand 12. After that, when the sub cam 142 and the main cam 162 rotate to a rotation angle of 0°, a switch (not shown) operates to stop the rotation of the motor.
Further, the rotation of the capstan 72 is also stopped, resulting in the stopped state shown in FIG.

As described above in detail based on the embodiments of the present invention, according to the present invention, during the movement of the tape unloading means toward the tape cassette due to the unloading operation of the magnetic tape, the magnetic Since the operating state of the brake means is controlled so that only the brake means on the reel stand on the side where the tape is not wound is in the operating state, it is possible to temporarily interrupt the recording operation due to the recording mode of the device once the tape is placed in the cassette. When recording is performed in the storage stop mode, the amount of tape wound around the storage reel hub is extremely small, so even if the tape loading and unloading operations are repeated, there is no major change in the tape position, and the recording is paused. Even if you switch to the recording mode from 1 to 3, the joint part of the previous recording overlaps and the previously recorded part is largely erased, or a large amount of open space is formed at the joint part, which is an inconvenience. At the same time, it is possible to prevent the tape from being damaged when it is removed from the cassette or when it is stored.
The effects are extremely large.

[Brief explanation of drawings]

Fig. 1 is a surface view of the main part of an embodiment of the present invention in a stopped mode, Fig. 2 is a schematic sectional view of the reel drive system, Fig. 3 is a surface view of the main part in a recording mode, and Fig. 4 is a magnetic Figure 5 is a front view of the main parts during tape storage operation, Figure 5 is a back view of the main parts in the stopped mode, Figures 6 and 7 are back views of the main parts during magnetic tape storage operation, and Figure 8 is the winding side brake. FIG. 9 is a cam lift curve diagram, and FIG. 10 is a graph showing the amount of tape wound onto the supply reel hub. 48... Main rod, 74... Capstan, 86... Idler gear, 130... Sub rod, 142... Sub cam, 162... Main cam, 43... Tight lever, 63... Cam lever, 118, 128... Tight pin, 112...
Take-up side brake, 122...Supply side brake, 1
80...magnetic tape, 186...rotating magnetic head drum.

Claims (1)

[Claims] 1 Using a tape cassette containing a pair of reel hubs capable of winding a magnetic tape, the magnetic tape is pulled out from the tape cassette and run along a rotating magnetic head drum installed outside the tape cassette to record or reproduce signals. A pair of reel stands 10, 12 configured as shown in FIG. A pair of brake means 112, 12 corresponding to the pair of reel stands
2, and a magnetic tape drawer that moves back and forth between a first position for drawing out the magnetic tape in the tape cassette and a second position for drawing the magnetic tape out of the tape cassette and attaching it to the rotating magnetic head drum at a predetermined angle. means 182, 183, and magnetic tape storage means 82, 86, 64 for storing the magnetic tape pulled out from the tape cassette into the tape cassette when the magnetic tape extraction means moves from the second position to the first position.
a, 64b, and in the movement of the magnetic tape pull-out means back from the second position to the first position, when the magnetic tape pull-out means is in the second position, the pair of brake means is in an inoperative state. None, during the movement from the second position to the first position, of the pair of brake means, only the brake means of the reel stand on the side that does not wind the magnetic tape is activated, and when the reel stand is located at the first position, Brake control means 43, 48, 63, 142, 16 which are in an operating state together with the pair of brake means.
0.0,162, and is configured so that when the pulled-out magnetic tape is stored in a cassette, the amount of magnetic tape transferred to the reel on the winding side is reduced.