JPH06101168B2 - Magnetic recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention allows a magnetic tape to be wound around a rotating cylinder on which a magnetic head is mounted to run so as to make a sliding contact between the magnetic head and the magnetic tape, and a predetermined information signal of a video signal. The present invention relates to a magnetic recording / reproducing apparatus such as a video tape recorder configured to record / reproduce.

2. Description of the Related Art In recent years, magnetic recording and reproducing devices such as cassette type video tape recorders have become smaller and lighter, and in camera-integrated video tape recorders, the diameter of the cylinder is set to 3/2 of the standard type, The type that uses a 4-head type small diameter cylinder with an angle of 285 ° is becoming mainstream.

The configuration of the conventional magnetic recording / reproducing apparatus is shown in FIGS.
Explain using Figure 15.

FIG. 12 is a plan view of a conventional magnetic recording / reproducing apparatus.

In FIG. 12, 1 is a cassette containing a reel around which a magnetic tape is wound, and 2 is a rotating cylinder in which magnetic heads 3a to 3d are divided into 90 ° on the circumference. The tape guide posts 4a and 4b are arranged inside the cassette opening (shown by a broken line) when the cassette is mounted, and when the cassette mounting switch is detected by the cassette detection switch (not shown), the tape guide posts 4a and 4b are moved to the first position. 12 Tape loading is performed along the path indicated by the arrow in the figure, and the tape is fixed in place.
5a and 5b are inclined posts, and the inclined posts 5a are fixed to the same base as the tape guide posts 4a. The inclined post 5b is fixed on the substrate 9. 6 is a magnetic tape 10
Is a capstan that causes the magnetic tape 10 to travel at a predetermined speed, and the pinch roller 8 presses the magnetic tape 10 onto the capstan 6 to rotate the capstan 6 against the magnetic tape.
The magnetic tape 10 is transmitted to the magnetic tape 10 at a predetermined speed.

FIG. 13 shows a rotary cylinder of a conventional magnetic recording / reproducing apparatus,
FIG. 14 is a view from above and FIG. 14 is a front view of FIG.

The fifteenth shows switching of heads when using a 4-head type small diameter cylinder, and magnetic heads are 3a → 3d → 3c.
Recording / playback is performed in the order of → 3b → 3a. The wrap angle of the rotating cylinder is 285 °, which is 3/2 times the standard type 190 °.

SUMMARY OF THE INVENTION However, in the above-described conventional configuration, in the standard having the standard wrap angle of 221 ° and the PCM audio track in addition to the video track, as in the 8 mm video format, the conventional example has been described. To reduce the size and weight of the device by using the 4-head type small diameter cylinder system, the wrap angle should be 331.5 ° (2
21 ° x 2/3 = 331.5 °), which inevitably reduces the gap between the rotating cylinder and the tape guide post, and requires high assembly precision in the manufacturing process, resulting in high yield. Had the problem of being bad.

In view of the above problems, the present invention is a magnetic recording / reproducing apparatus in which the posts located in front of and behind the rotary cylinder are arranged in parallel with the axis of the cylinder of the rotary cylinder to ensure a precise gap between the rotary cylinder and the post. It is intended to provide.

Means for Solving the Problems In order to achieve the above object, a magnetic recording / reproducing apparatus of the present invention includes a rotary cylinder having a magnetic head, a substrate on which the rotary cylinder is mounted, and a reel around which a magnetic tape is wound. The magnetic tape is pulled out from the cassette to the outside of the cassette, wound around the rotary cylinder at a predetermined angle, and positioned parallel to the central axis of the rotary cylinder. And a stopper pin that is set on the substrate in parallel with the central axis of the rotary cylinder and that holds the post together with the lower cylinder portion of the rotary cylinder.

With the above configuration, the post that pulls out the magnetic tape from the cassette is fixed in parallel with the central axis of the cylindrical surface of the rotary cylinder, so that the clearance between the rotary cylinder and the post and the post is as large as possible and highly accurate. Positioning can be realized.

Example Hereinafter, a magnetic recording substrate device of an example of the present invention,
A description will be given with reference to the drawings.

FIG. 1 is a schematic plan view of a magnetic recording / reproducing apparatus according to an embodiment of the present invention. Reference numeral 2 is a rotating cylinder, which is a magnetic tape pulled out from the cassette 1 mounted in the magnetic recording / reproducing apparatus.
10 is wound around the outer peripheral surface in an M shape over a range of 331.5 °. The rotating cylinder 2 has four magnetic heads.
Make sure that 3a, 3b, 3c, 3d slightly project the tip and
It is divided into ° and arranged on the circumference. On the outer circumference of the rotary cylinder 2, loading rings 11a and 11b are rotatably provided for guiding the magnetic tape 1 drawn out from the cassette 1 to be wound around the outer peripheral surface of the rotary cylinder 2. This loading ring 11a has a tape guide post 12a, 12b and a post 13 fixed parallel to the rotary cylinder 2 when the tape loading is completed.
A shaft holder 14a holding a is attached, and a tape guide post 12c is also attached to the loading 11b.
And, when the tape loading is completed, a shaft holder 14b holding a cassette 13b fixed in parallel with the rotary cylinder 2 is attached.

The loading motor 15, which is a drive motor for loading operation, and the cam gear 16 mesh with each other via a worm 17, and the loading ring 11a and loading 1
1b is connected by a relay gear A18 and a relay gear B19, and the loading rings 11a, 11b are configured so that their rotating directions are opposite to each other. Tape guide post 12a, 12 above
The magnetic tape 10 wound around the c is wound around the rotary cylinder 2 when the loading ring 11b is rotated clockwise and the loading ring 11a is rotated counterclockwise.

A cassette mounting portion for mounting a cassette is formed on the side of the base that faces the rotary cylinder 2, and the mounted cassette 1 is held at a predetermined position in the cassette mounting portion, and a cassette mounting detection switch (not shown). When the mounting of the cassette is detected by (1), the loading motor 15 rotates the cam gear 16, and the drive arm 21 having the cam pin 20 corresponding to the cam portion of the cam gear 16 causes the sub chassis 31 to rotate on the substrate 32. It is moved in the direction of cylinder 2. The cassette 1 moves in the direction of the rotating cylinder 2, and the rotating cylinder 2 is arranged in the opening of the cassette 1. The cassette mounting portion is provided with a pair of reel stands 22 and 23. The cassette 1 includes a tape supply reel 24 and a tape take-up reel 25 around which the magnetic tape 10 is wound, and corresponding reel stands 22 and 23, respectively. It is fitted and fitted to.

26 is a capstan that rotates at a predetermined number of revolutions to allow the device to run the magnetic tape 10 at a predetermined speed in the recording / reproducing mode, 27 is a capstan motor that gives a rotational force to the capstan 26, and 28 is a magnetic field for the capstan 26. A pinch roller that presses the tape 10 and transmits the rotational force of the capstan 26 to the magnetic tape 10. 29 is a magnetic tape for recording / playback 10
Impedance roller 30 is provided for the purpose of suppressing the longitudinal vibration generated in the magnetic tape 10, and is a tension regulator post 30 for detecting the tension, which is provided to give a constant tension to the magnetic tape 10.

Next, the structure of the rotary head cylinder of the 4-head system will be described. The 8 mm video tape format is shown in FIGS. 3a and 3b.

As is well known, in the 8 mm video format, a PCM audio track of 28.5 ° is added in addition to the track part for recording image signals (180 °), so the wrap angle of the standard cylinder (2 head type) is 221 °. It has become. In order to reduce the size of the rotary cylinder while keeping this standard, as in the case of the conventional example, a 4-head type small-diameter cylinder type configuration is adopted. As shown in FIG. 4, the four magnetic heads 3a, 3
When b, 3c, and 3d are sequentially switched to enable recording and rewriting, the tape winding angle on the rotating cylinder is 3/2 times 221 °.
It becomes 331.5 °. Also, the tape wrapped around the rotating cylinder must be folded back at an acute angle to prevent overlap (for the 8m / m standard).

Next, a method of fixing the posts 13a and 13b that are fixed in parallel with the rotary cylinder 2 when the tape loading is completed will be described with reference to FIGS.

FIG. 5 is a schematic plan view showing the structure of the stocker pin 33 for accurately fixing the posts 13a and 13b at predetermined positions, and FIG. 6 is a front view thereof. 7 and 8 are side views showing a schematic configuration of the shaft holders 14a and 14b.

In FIGS. 5 and 6, the stopper pin 33 is erected on the substrate 32 in parallel with the central axis of the cylindrical surface of the rotary cylinder 2. The posts 13a and 13b attached to the shaft holders 14a and 14b are directly sandwiched by the cylindrical portion of the lower cylinder 34 (the diameter of which is larger than the diameter of the cylinder by a step forming a lead) and the stopper pin 33. Fixed as. Further, as shown in FIGS. 7 and 8, the shaft holders 14a and 14b have projections 14a 'and 14b extending and abutting against the lower mounting surface 34' of the lower cylinder 34 for preventing floating in the vertical direction. 'Is provided. Therefore, the positional accuracy of the posts 13a and 13b with respect to the rotary cylinder 2 in plan view is such that the posts 13a and 13b are brought into contact with the cylindrical portion of the lower cylinder 34 of the rotary cylinder 2 and the substrate 32 on which the lower cylinder 34 is mounted. In addition, since the posts 13a and 13b are brought into contact with the stopper pin 33 vertically erected on the mounting surface of the lower cylinder 34, the positioning can be performed with high accuracy. In addition, the protrusions 14a ′, 1 provided on the shaft holders 14a, 14b
Since 4b 'is configured to directly contact the mounting surface 34' of the lower cylinder 34, the tape guide posts 12a, 12b
The height position of c can be secured with high accuracy.

The operation of the magnetic recording / reproducing apparatus configured as described above will be described below. FIG. 9 is a schematic plan view of a state immediately after the cassette is mounted on the magnetic recording / reproducing apparatus.

As shown in FIG. 9, in this state, the tape guide posts 12a, 12b, 12c, 12e, the posts 13a, 13b, 13c, the pinch roller 28, and the tension regulator post 30 are located inside the cassette opening. Next, when the mounting of the cassette is detected by the detection switch (not shown), the loading motor 15 starts rotating. The rotational force of the loading motor 15 is transmitted to the cam gear 16 via the worm 17, and the drive arm 21 is driven by the cam pin 20 corresponding to the cam groove.
Is rotated clockwise, and the sub-chassis 31 on which the reel stands 22 and 23 are arranged and which holds the cassette 1 is moved in the direction of arrow A. At the same time as the operation of the subchassis 31 and the like, the loading 11b that directly meshes with the cam gear 16 is rotated clockwise, and the loading ring 11a is rotated counterclockwise, so that the posts 13a and 13b and the tape guide post are rotated. 12a, 12b, 12c are moved and fixed so that the magnetic tape 10 is wound around the rotating cylinder 2 by a predetermined angle. Further, the tape guide post 12e, the post 13c, the pinch roller 28, and the tension post 30 are also moved to the positions shown in FIG. 1 and fixed.

For reference, FIG. 10 is a schematic side view showing the positional relationship between the rotary cylinder 2 and the cassette 1 when the cassette is mounted, and FIG.
The figure is a schematic side view showing the positional relationship between the rotary cylinder 2 and the cassette 1 after the tape loading is completed.

Next, the tape running path of this embodiment will be described with reference to FIG.

The magnetic tape 10 that has exited the supply reel 24 is pulled out of the cassette 1 from the cassette 1, and the tape guide post 12f, the tension regulator post 30, the impedance roller 29,
Between the tape guide post 12c and the post 13b, the substrate 32
Is pulled out horizontally. The magnetic tape 10 is twisted by the post 13b, and the twisted tape and the post 13 are
b is inclined by the lead angle (4.885 ° in the 8mm video standard). The magnetic tape wound around the rotary cylinder 2 is gradually lowered along the lead of the rotary cylinder 2, wound at a predetermined angle, then wound around the post 13a and twisted again, and then the tape guide post 12a,
Ascends through 12b, and returns to almost the standard height at the position of the tape guide post 12d through the capstan 26. Further, the post 13c removes the twist, and the substrate is wound again on the winding reel in a horizontal state. Posts 13a, 13
The wrap angles of b and 13c are 50 °, 110 ° and 23 ° respectively, and the inclinations with respect to the magnetic tape 10 are 4.885 ° (lead angle) and 4.88, respectively.
5 ° (lead angle) and 25 °.

As described above, according to this embodiment, after the completion of loading,
The same cylinder of the lower cylinder 34 of the rotating cylinder 2 and the substrate 32
Since the posts 13a and 13b are brought into contact with and sandwiched by the stopper pin 33 vertically erected on the mounting surface 34 'of the lower cylinder 34, the posts 13a and 13b can be positioned with high precision. Becomes Also shaft holder
The protrusions 14a ′ and 14b ′ of 14a and 14b are attached to the mounting surface 3 of the lower cylinder 34.
The shaft holder 1
The height positions of the tape guide posts 12a, 12b, 12c arranged on the 4a, 14b can be secured with high accuracy.

Advantageous Effects of Invention According to the present invention, the magnetic tape is pulled out of the cassette from a cassette having a rotary cylinder equipped with a magnetic head, a substrate on which the rotary rotary cylinder is mounted, and a reel around which a magnetic tape is wound. A post that is wound around the cylinder at a predetermined angle or is positioned parallel to the central axis of the rotating cylinder, and the inclined post together with the lower cylinder portion of the rotating cylinder that is installed on the substrate in parallel with the central axis of the rotating cylinder. Since the stopper pin for holding is provided, the positioning accuracy of the tilt post is determined by the positioning accuracy of the stopper pin and the rotary cylinder on the substrate, and highly accurate positioning can be realized.

[Brief description of drawings]

1 is a schematic plan view of a magnetic recording / reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a front view thereof, FIGS. 3a and 3b are schematic views showing an 8 mm video format, and FIG. 4 is a schematic view of the present invention. FIG. 5 is a schematic view showing an 8 mm video format of a magnetic recording / reproducing apparatus of one embodiment, FIG. 5 is an enlarged plan view of the vicinity of a tilt post of the apparatus, FIG. 6 is a front view of the apparatus, and FIGS. FIG. 8 is a side view showing the details of the shaft holder, FIG. 8 is a perspective view of the substrate of the apparatus, FIG. 9 is a schematic plan view immediately after the cassette is mounted in the apparatus, and FIG. 10 is a schematic immediately after the cassette is mounted in the apparatus. FIG. 11 is a side view, FIG. 11 is a schematic side view of the apparatus when tape loading is completed, FIG. 12 is a schematic plan view of a conventional magnetic recording / reproducing apparatus, and FIGS. 13 and 14 are main parts of the apparatus, respectively. Fig. 15 is a plan view and its side view, and Fig. 15 is in the conventional format.
It is a schematic diagram explaining a format when a head type cylinder is used. 1 ... Cassette, 2 ... Rotating cylinder, 3 ... Magnetic head, 10 ... Magnetic tape, 12 ... Tape guide post, 13
…… Post, 14 …… Shaft holder, 26 …… Capstan, 27 …… Capstan motor, 28 …… Pinch roller, 29 …… Impedance roller, 30 …… Tension regulator post, 31 …… Sub chassis, 32… …
Substrate, 33 …… V stopper, 34 …… Lower cylinder.

Claims (1)

[Claims] 1. A rotary cylinder provided with a magnetic head, a substrate to which the rotary cylinder is attached, and a magnetic tape winding reel, the magnetic tape is pulled out from the cassette to a predetermined position in the rotary cylinder. A post that is angle-wound and positioned parallel to the central axis of the rotary cylinder; and a stopper pin that is set on the substrate in parallel with the central axis of the rotary cylinder and that holds the post together with the lower cylinder portion of the rotary cylinder. A magnetic recording / reproducing apparatus having.