JPS63121161A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent a tape from being damaged, by controlling tape tension at a prescribed value in loading/unloading even when a height difference between a guide post which catches the tape and the tape exists, at the time of loading/unloading the tape. CONSTITUTION:A sensor functions so that, at the time of loading, a tape tension post 6 controls a magnetic tape 8 at a constant tension after the tape tension guide 6 draws out the magnetic tape 8 in parallel from a cassette 1, from a time when at least either the tape guide posts 7, 12, or 14 on a loading ring 27 catches the tape until the loading is completed. And at the time of unloading, during until the tape guide post 6 is separated from the tape after starting the unloading, the tape tension post 6 controls the magnetic tape 8 at the constant tension. In such way, it is possible to prevent the tape from being damaged even when the difference between the guide posts 7, 12, and 14 studding on the loading ring 27 and the tape 8 to be caught exists.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to magnetic recording and reproducing devices such as video tape recorders.

Conventional technology A conventional example will be described below with reference to the drawings.

FIG. 6 shows an example of a tape running system for U loading when the winding angle of the magnetic tape 8 around the head drum 9 is 216 degrees. Reference numeral 1 designates a cassette with two -j-pleels, 4 a guide post, 5 an erasing head, and 6 and 7 a supply tension post and a supply guide post, respectively. 9 is the head drum, 13 is the A/C head, 23
24 is a main inclined post, 24 is a tape guide, 26 is a tension post on the winding side, and 26 is a tape guide.

The magnetic tape 8 from the supply tape reel 2 to the head drum entrance point 10 is not twisted or changes in height.

The guide posts 12 and 14, the capstan 15, the turn post 16, the pinch roller 17, and the guide post 18 installed on the loading ring 27 all pass through the center of the magnetic tape 8 at the head drum exit point 11,
It is provided perpendicularly to the first # diagonal running surface perpendicular to the magnetic tape 8 .

Reference numeral 19 denotes a sub-inclined post installed on the loading ring 27, and is not provided perpendicularly to the first inclined running surface. The magnetic tape that has run on the first inclined running surface through the sub-inclined post 19 forms a second inclined running surface after passing through the sub-inclined post 19.

31 is the first inclined running surface and the reel 2.3 in the cassette;
, and 28 is a line of intersection with the second inclined running surface. However, crossing! 28 is located on the loading ring 27 as shown in the figure only when loading is completed. Therefore, during loading and unloading operations, the intersecting line is located at 31, and when the turn post 16 catches the magnetic tape 32 during loading, the turn post 16 and the magnetic The tapes 32 will have different heights.

Further, the tape guides 1B, 20, 21, and 22 set up on the loading ring 27 also come into contact with the magnetic tape while maintaining a height difference therebetween.

Problems to be Solved by the Invention However, with the above configuration, loading and
There was a problem in that if the tape tension during unloading was even slightly high, the tape would be damaged. In view of the above-mentioned problems, the present invention provides a magnetic recording and reproducing apparatus that eliminates tape damage by controlling the tape tension at a constant level during tape loading and unloading.

Means for Solving the Problems - In order to solve the above problems, the magnetic recording and reproducing apparatus of the present invention provides that, at the time of loading, the tape tension compost on the winding side pulls out the magnetic tape from the inside of the cassette in parallel. , the leading guide post stands on the loading ring and catches the tape pulled out by the take-up side tape tension post, and the take-up side chill tension post catches the tape until the loading leg is completed. controls the constant tension of the tape supplied from the take-up tape reel, and during unloading, the take-up tape tension is maintained from the start of unloading until the leading guide post leaves the tape. The post controls the constant tension of the tape being wound onto the take-up tape reel.

Effects of the present invention With the above-described configuration, the tape tension for loading and unloading can be set to a low value without any difference in the winding diameter of the tape in the reel, so that the tape tension can be set to a low value without any difference in the winding diameter of the tape in the reel. Even if there is a height difference between the caught tape and the tape, damage to the tape can be eliminated.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 4 of the drawings. Note that the same members as in the conventional example are given the same reference numerals, and their explanations will be omitted.

A spur gear is cut on the outer periphery of the loading ring 27 which is rotationally driven by a drive device (not shown), and there is a spur gear part that meshes with this spur gear, and a bevel gear for surface conversion below it. A relay two-stage gear 34 having a section is disposed parallel to the first inclined surface.

35 is a large gear having a bevel gear part that meshes with the bevel gear part of the relay two-stage gear 34;
The hand inner wall portion 3 that constitutes the Geneva intermittent mechanism with the lever of
5-a, 35-b and a kick bin 36, and is rotatably provided on a rotation support shaft 51. A first lever 37 is rotatably mounted on the support shaft 38, and engages with an elongated hole of a second lever 41 to rotate the second lever 41. 4
Reference numeral 3 denotes a tension sub-arm rotatably mounted on a support shaft 51, and a kick bin 42 mounted on a second lever 41 engages with an elongated hole of the tension sub-arm 43 and rotates. Reference numeral 33 denotes a take-up side tension arm, which is arranged in a plane parallel to the reel plane. A plate spring 46 (not shown in FIGS. 2 and 3) and a plate spring are attached to the tension sub-arm 43 to bias the curly side tension arm 33 counterclockwise and balance the tape tension to create a predetermined tension. A plate 46 is provided on the take-up side Tensilan arm 33, and a magnetic element 60 (not shown in FIGS. 2 and 3) is attached to a sensor base 49 (not shown in FIG. 2). A magnet 48 and a magnet holder 47 holding the magnet 48, which together constitute a sensor, are fastened and fixed.

Further, a kick pin 44 implanted at one end of the tension sub-arm 43 engages with a notch in the leaf spring mounting plate 45, so that the tension sub-arm 43 rotates the winding-side tensicon arm 33. It has become.

Next, the operation will be explained using FIGS. 1, 2, and 3.

Due to the drive source, the loading ring 27 rotates 410 degrees, and the first 100' of the rotation rotates around the guide post 4. Pull out the supply side tension post 6 and the take-up side tension post. At that time, the rotation ratio between the loading ring 27 and the large gear 35 is set to approximately 1. During loading, when the coding ring 27 rotates in the direction of arrow A, the relay two-stage gear 34 rotates clockwise and the large gear 35 rotates counterclockwise. The pin 36 mounted on the large gear 36 engages with the notched groove of the first lever 37 and rotates the first lever 37. The pin 39 placed on the first lever 37 rotates the second lever 41 counterclockwise, and the pin 42 placed on one end of the second lever 41 is placed in the notched groove of the tensicon sub-arm 43. to rotate the tension sub-arm 43 clockwise.

A kick bin 44 installed at the other end of the tension sub-arm 43 rotates the winding-side tension arm 33 clockwise via a leaf spring mounting plate 45.

The above operation is performed from the unloading completion state to the first approximately 1 of the total rotation angle 41o0 of the loading ring 27.
Completed during 00°. After that, the tension post 2 on the take-up side will be
6 is located at the same position as when the tape is running, so that the sensor composed of the magnet 48 and the magnetic element 5o can also be detected. Therefore, the reel motor directly connected to the take-up reel stand, Closed-loop constant tension control is possible.

In particular, when the supply reel stand is stopped by the brake device during loading and the tape is pulled out only from the take-up reel, high tension is generated due to differences in tape winding diameter and tension fluctuations, resulting in tape damage. By performing constant tension control as described above, tape damage can be eliminated.

Also, even during unloading, the winding side Te/7=I
Until the turn arm 33 begins to rotate, constant tension control is possible and damage to the tape can be prevented.

Effects of the Invention As described above, according to the present invention, the tape tension can be maintained at a predetermined value during loading and unloading even if there is a height difference between the guide post that catches the tape and the tape. Since it can be controlled, excellent effects such as being able to prevent tape damage can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an overview of the tape running system of a magnetic recording/reproducing device according to an embodiment of the present invention, FIG. 2 is a plan view of the main mechanism of the device in a state in which unloading is completed, and FIG. 3 is a plan view of the same device. FIG. 4 is a side sectional view of the main mechanism of the apparatus in a tape tension controllable state, and FIG. 5 is a plan view showing an outline of a conventional tape running system. 9... Head drum, 16... Turn post, 26... Winding side tension post, 3
3...Take-up side tension arm, 48...
...Magnet, 5°...Magnetic element. Name of agent: Patent attorney Toshio Nakao and 1 other person rl
s-J claws yyvxytzk 27-0-te-on 7-song 3j-1J-like tension 5 tour 4 34--one cut square gear 35--su, @ base 37-°-lever (angle 4 (-"<bl 45--ru song introduction 3 vinegar

Claims (2)

[Claims] (1) A rotating head drum, a loading ring having a plurality of tape guide posts for winding the magnetic tape around the head drum and arranged at an angle around the head drum, and a tape cassette for winding the magnetic tape. A tension arm having a tape tension post pulled out from the magnetic tape and making contact with the magnetic tape and causing displacement depending on the magnitude of the tension of the magnetic tape, and a sensor detecting the displacement of the tension arm to detect the tape tension, During loading, after the tape tension post pulls out the magnetic tape in parallel from inside the cassette, at least one of the tape guide posts on the loading ring catches the tape, and then the magnetic tape is pulled out in parallel from the inside of the cassette. During unloading, the tape tension post controls the magnetic tape at a constant tension, and after unloading starts, the tape guide post
A magnetic recording/reproducing device characterized in that the tape tension post controls the magnetic tape at a constant tension until the tape is separated from the tape. (2) The magnetic recording and reproducing apparatus according to claim 1, wherein the tension arm is provided on the winding side of the magnetic tape.