JPH0343701B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording and reproducing device, and in particular, in releasing a locked state of an operation mode by operating a tape end detection mechanism using a planetary gear device.
The object of the present invention is to be able to reliably release the operation mode at the end of the tape without adversely affecting the running of the magnetic tape, and to achieve significant miniaturization including a mechanism for releasing the locked state.

A conventional tape end detection mechanism using a planetary gear device includes an end detection wheel that automatically reverses at the end of the tape in the planetary gear device, and a detection lever that releases the operation mode is pressed against the end detection wheel by a spring or the like. , while the tape is running, the end detection wheel rotates forward, the detection lever escapes from the release part of the detection wheel, and when the tape reaches the end, the end detection wheel automatically reverses, the detection lever bites into the release part of the detection wheel, There is a device in which the detection lever cancels the current operating mode by the reverse driving force of the detection wheel. In this type of device, there is an elastic member such as a spring between the end detection wheel and the detection lever, so the frictional force on the circumferential surface of the end detection wheel adversely affects the running of the magnetic tape and consumes energy during recording and playback. This required an extra current.

The present invention eliminates the above-mentioned conventional drawbacks, and utilizes a tape end detection device having a planetary gear system, which does not affect the running of the tape in any way and consumes less current consumption for the tape end detection device. The present invention provides a magnetic recording and reproducing device equipped with an operation mode unlocking device. An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a plan view of the main parts of the magnetic recording/reproducing apparatus of this embodiment showing a stopped state, and FIG. 2 is a side view of the apparatus. In Fig. 1, reference numeral 1 denotes a winding reel stand with a gear 2 integrally provided at the bottom thereof, and is rotatably mounted around a shaft 5 implanted in a lower substrate 4 which is fixed integrally with a substrate 3. It is being
Reference numeral 6 denotes a drive gear driven by a motor (not shown); 9 is pressed from the upper surface by a compression spring 7; and the lower surface is connected to the drive gear 6 via a winding friction member 8.
It is a winding gear to which power is transmitted. The gear 2 of the reel stand meshes with the take-up gear 9 and, on the other hand, with a control gear 10 of a planetary gear set, which will be described later. Note that the driving gear 6 and the winding gear 9 are rotatably mounted around a shaft 11 implanted in the lower substrate 4,
The upper substrate 12, which is integrally fixed to the substrate 3, prevents it from coming off.

The planetary gear device is rotatably mounted around a shaft 13 embedded in the lower substrate, and the control gear 10 coupled to the gear 2 of the reel base, the sun gear 14 and the detection gear 15 are connected to this shaft 13 as described above. Rotate around the center of rotation. A gear 14a is integrally provided on the outer periphery of the central shaft portion of the sun gear 14, and a gear 14b is also integrally provided on the outer periphery of the sun gear 14. An intermediate gear 16 rotatably provided on a shaft 17 implanted in the lower substrate 4 is coupled to the lower gear 6a of the drive gear 6 and the gear 14b of the sun gear 14, and the sun gear 14 is connected to the intermediate gear 14. 16, it is always rotated in a constant direction at a constant speed during operations such as playback and recording. Furthermore, a rotatable planetary gear 18 is disposed on a shaft 10a integrally provided below the control gear 10, and this planetary gear 18 is connected to a center gear 14a of the sun gear 14. Furthermore, the planetary gear 18 is an internal gear 15a of the detection gear 15.
It is also connected to The detection gear 15 is inscribed in the inner wall of the gear 14b on the outer periphery of the sun gear 14, is rotatable, and is similarly prevented from coming off by the control gear 10, which is prevented from coming off by the upper substrate 12. Two detection claws 15 are provided at 180° symmetrical positions on the upper outer periphery of the detection gear 15.
b is integrally formed.

The detection lever 19 for coming into contact with the detection pawl 15b of the detection gear 15 is rotatably provided on the lower side of the substrate 3 about a shaft 20a formed integrally with the release lever 20, and is mounted on the substrate 3. Rotation is regulated by a stopper 21 provided. The ends of both arms of the detection lever 19 are provided with a trace claw 19a for tracing the detection claw 15b of the gear 15, and a release claw 19b for releasing the playback lock mechanism at the end of the tape by the detection claw 15b. has been done. Further, the release lever 20 has a lock pin 22a that is integrally installed in the lock arm 22.
It is rotatable around the center and is located between the operating rod 23 and the base plate 3.

The operating rod 23 is slidable while being guided by guide pins 24 and 25 embedded in the base plate 3, and is prevented from coming off by fastening parts (not shown) on the guide pins 24 and 25. It is also biased to one side by a spring 27, one end of which is hung on this operating rod and the other end is hung on a hook 26 embedded in the board 3.
Furthermore, a pin 28 implanted in the operating rod 23
is inserted into the square hole of the release lever 20, and as the operating rod 23 slides, the release lever 20 is released.
It is configured to rotate. Note that when the operating lever 23 slides to the left, the release lever 20
Guide pin 2 is attached to the board 3 so as to move the
9 is implanted, and a pin 28 is implanted in the operating rod 23. Next, in order to lock the operating rod 23, a lock pawl 23a that engages with the locking pin 22a is formed integrally with the operating rod 23. The lock arm 22, on which the lock pin 22a is implanted, rotates around a shaft 30 implanted in the lower substrate 4, and one end is hung on a hook 31 implanted in the lower substrate 4, and the other end is attached to the hook 31 implanted in the lower substrate 4. A tension spring 31 attached to the lock arm 22 urges the lock arm 22 to rotate clockwise.

Next, the operation of the configuration of the above embodiment will be explained. FIGS. 3 and 4 are plan views during tape constant speed running operations such as recording and reproduction.

First, when the operating rod 23 is manually pushed in to lock the operating rod 23 (described later) and tape constant speed running operations such as recording and playback are started, the drive gear 6 is rotated in the direction of arrow A by the rotation of a motor (not shown). The take-up gear 9 is rotated in the same direction via the take-up friction member 8, the gear 2 is further rotated in the direction of arrow B, and the reel base 1 integrated with the gear 2 is rotated in the direction of arrow B, thereby removing the cassette. Wind the tape in a certain direction. (The reel stand 1 is a take-up reel stand.) On the other hand, the rotation of the drive gear 6 causes the intermediate gear 16 to rotate in the direction of arrow C, causing the sun gear 14 to rotate at a constant speed in the direction of arrow D. In addition, the control gear 1 is rotated by the rotation of the gear 2 integrated with the reel stand 1.
0 in the direction of arrow D. At the same time, the shaft 10a integrally formed with the control gear 10 rotates in the E direction, the planetary gear 18 rotating around this shaft 10a revolves in the E direction, and the center outer circumference of the sun gear 14 rotates. The gear 14a rotates in the direction of arrow F, and the planetary gear 18 rotates in the direction of arrow G.

The reel stand 1 allows the tape to be fed at a constant speed by a capstan and a pinch roller (not shown), so that the take-up friction member 8 may slip due to the difference in rotational speed between the take-up gear 9 and the drive gear 6. The material is wound onto the hub in the cassette by the constant winding force generated by the winding. Here, as described above, the control gear 10 rotates based on the rotation speed of the reel stand 1, but the rotation speed of the sun gear 14 is reduced by the gear 6a of the drive gear 6 and the intermediate gear 16, and the reduction ratio is as described above. The detection gear 15 rotated by the planetary gear 18 is set to rotate in the direction of arrow H.

On the other hand, when the operating rod 23 is pushed to the left in the figure against the spring 27, the lock pawl 23a engages the lock pin 22.
Rotate the lock arm 22 while pressing against the tension spring 32 so as to push up the lock pawl 23a.
If the lock pin 2 goes too far, the tension spring 32
2a locks the lock pawl 23a, and the operating rod 23 becomes locked by the force of the spring 27 at the locking position of the lock pin 22a and the lock pawl 23a. At the same time, the pin 28 of the operating rod 23 inserted into the square hole of the release lever 20
is rotated to the left in the figure so as to rotate around the lock pin 22a of the lock arm 22. Therefore, the detection lever 19 approaches the detection gear 15, and the tracing claw 19a and release claw 19b, which are integral with the detection lever 19, come into contact with the detection claw 15b of the detection gear 15. Since the detection gear 15 rotates in the direction of arrow H, the detection lever 19 swings along the detection pawl 15b of the detection gear as shown in FIGS. 3 and 4.

Next, when the reel stand 1 stops at the end of the cassette tape, the winding friction member 8 slides as shown in FIG. 5, and the winding gear 9 meshing with the gear 2 of the reel stand 1 stops, and the control Gear 10 stops. On the other hand, the drive gear 6 is continuously rotated by the motor in the direction of the arrow A, so that the sun gear 14 is always rotated in the direction of the arrow F via the intermediate gear 16. Gear 14a on the outer periphery of the center of this sun gear 14
The planetary gear 18 coupled to the control gear 10 does not revolve around the control gear 10, but only rotates in the direction of arrow G due to the rotation of the gear 14a of the sun gear 14. Therefore, the detection gear 15 automatically reverses in the direction of arrow I.

The trace pawl 19a of the detection lever 19 is shaped so that it rides on the outer periphery of the detection pawl 15b with respect to the detection gear 15 rotating in the I direction, while the release pawl 19b of the detection lever 19 is shaped so as to sink into the outer circumference of the detection pawl 15b. It is a shape. Therefore, the detection gear 15
During at least 1/2 rotation in the direction of arrow I, the release pawl 19b engages with the detection pawl 15b, and as shown in FIG. While being guided upward by the guide pin 29 on the board 3 and the pin 28 on the operating rod 23, move the release lever 20 in the direction of arrow J.
The lock arm pin 22a integrated with the lock arm 22 is rotated upward while resisting the tension spring 32. Therefore, the engagement between the lock pawl 23a of the operating rod 23 and the lock arm pin 22a is disengaged, and the operating rod 23 is moved in the direction of arrow K by the bias of the tension spring 27 and returned to the stop mode position. Of course, in the case of a reciprocating reversal type magnetic recording/reproducing apparatus, the running direction of the magnetic tape may be reversed using another output member instead of the return operation of the operating rod 23.

According to the configuration of the above embodiment, the detection gear 15 is
180 It has two detection claws 15b at symmetrical positions, while the detection lever 19 is pivotally supported at the center by a pin 20a and can swing freely, and one claw at each end of both arms, that is, tracing claws 19a. , release claw 1
9b, the detection gear 1 rotates together with the reel stand 1 during playback, recording, etc.
When the two claws 19a and 19b of the detection lever come into contact with the detection lever 5, at least one of the claws touches the detection claw 15b.
If it rides on the detection gear 15b, the other claw will come into sliding contact with the detection gear 15 which does not have the detection claw 15b, so there is no need to always keep the release claw in elastic contact with the detection gear using an elastic member such as a spring as in the conventional case. It is. That is, in the configuration of the above-described embodiment, the detection gear 15 reverses immediately when the reel stand stops, and the release claw 19b
is in sliding contact with the detection gear 15, so the detection claw 15b
Always engages. Therefore, in this example,
In addition to eliminating the need for conventional elastic members, the frictional force generated on the circumferential surface of the detection gear 15 is extremely small, and the lock release mechanisms such as the detection lever 19 and release lever 20 improve the rotational performance of the reel stand and tape running performance. It has no negative effect on the Since the generation of frictional force is small, power consumption does not increase.

Furthermore, in the above configuration, since the detection claws 15b are provided at two locations (180° opposing positions) on the detection gear 15, after the reel stand has stopped, the detection gear 1
Be sure to turn the detection claw 15 while 5 rotates at least 1/2
Since the release claw 19b engages with the release claw 19b, it is possible to quickly release the lock at the end of the tape.

In addition, as described above, the structure does not require an elastic member, and at the same time, the rotation fulcrum of the release lever 20 is
By sharing the operating lever 23 with the lock pin 22a, it is possible to significantly reduce the size and weight of the tape end detection and lock release mechanism.

Although the above embodiment describes a device using a cassette tape, the present invention can also be applied to a reel-to-reel type device, as long as both ends of the magnetic tape are attached so that they do not come off the reel. It can be applied not only to a tape recorder for recording audio but also to a video tape recorder for recording images, and can also be applied to detecting the end of a magnetic tape wound around a magnetic drum in a computer device or the like.

As described above, the present invention includes a control wheel that receives the rotation of the reel stand, a planetary wheel having a support shaft on the control wheel, and an internally toothed detection wheel sandwiching the planetary wheel between the sun wheel. The rotational force from the motor is always transmitted to the sun wheel, and the detection wheel has two detection claws at 180° symmetrical positions, and two claws are attached to each end of both arms for this detection wheel. By making the swingable detection lever slidable, the two claws of the detection lever slide into sliding contact with the rotating detection wheel during playback and recording, and when the reel stand stops, the detection wheel is quickly reversed. The detection claw engages with the detection lever claw to release the locked state. The configuration of the detection wheel and detection lever allows them to be in sliding contact with each other at all times during operation, and there is no need for an elastic member to constantly press them together, and the sliding contact can be made with a very light load. Therefore, it is possible to provide a magnetic recording and reproducing apparatus that does not adversely affect the rotation of the reel stand or the running of the tape during operation, and does not consume excess power due to friction. Furthermore, since it has a simple configuration as described above, it has many advantages such as being small, lightweight, and inexpensive to manufacture.

[Brief explanation of drawings]

FIG. 1 is a plan view of essential parts of an embodiment of the magnetic recording/reproducing apparatus of the present invention in a stopped state, FIG. 2 is a side view thereof, and FIGS. 3 and 4 are plane views showing operating states of recording or reproduction. 5 and 6 are plan views showing the release operation of the operating lever. DESCRIPTION OF SYMBOLS 1... Reel stand, 3... Board, 4... Lower board, 6... Drive wheel, 8... Winding friction member, 9...
... Winding gear, 10 ... Control gear, 12 ... Upper board, 14 ... Sun gear, 15 ... Detection gear, 15
b...detection claw, 16...intermediate gear, 18...planetary gear, 19...detection lever, 19a...trace claw, 19b...release claw, 20...release lever, 2
2...Lock arm, 22a...Lock pin, 2
3...Operation rod, 23a...Lock claw, 27...
...Spring, 32...Tension spring.

Claims (1)

[Scope of Claims] 1. A reel stand rotatably provided on a substrate for winding a tape, and a planetary gear device that receives the rotational drive of the reel stand and another constant speed rotational drive. , the planetary gear device is provided with a control wheel that receives the rotational drive of the reel stand, a sun wheel that receives the constant speed rotational drive, and further has a planetary wheel that rotates around a rotating shaft that is integrated with the control wheel. The planetary wheel is configured to mesh between the external gear of the sun wheel and the internal gear of the detection wheel, and while the tape is running, the control wheel, sun wheel, and detection wheel are rotated forward in the same direction, and the tape ends. When the rotation of the reel stand is stopped, the planetary wheel rotates and the detection wheel is reversed in the opposite direction to the control wheel, and two point-symmetric detection claws are provided on the outer periphery of the detection wheel. and a detection lever having a rotation center has two arms, one of which is provided with a tracing claw and the other with a release claw at the tip of each arm for contacting the detection claw of the detection wheel. , that trace nail,
The release pawl is shaped so that when the detection wheel rotates forward, the pawls at both ends escape, and when the detection wheel reverses, one of the release pawls bites into the detection pawl. and a release lever engaged with the locking member, the detection wheel rotates in the normal direction while the tape is running, and the tracing claw of the detection lever and the release claw of the detection lever move the outer periphery by the detection claw of the detection wheel that rotates in the normal direction. At the end of the tape, the detection wheel is reversed, and the release claw of the detection lever bites into and engages with the detection claw of the reversing detection wheel, and the release lever is moved by the reversal driving force of the detection wheel. 1. A magnetic recording and reproducing device characterized in that it is configured to be released from a locking member. 2. The magnetic recording and reproducing device according to claim 1, wherein the rotation shaft of the release lever is also used as a locking pin that engages with a locking pawl of a locking member.