KR930009230B1 - TAPE LOADING SYSTEM OF 8mm VTR - Google Patents

Abstract

This tape running device that can remarkably reduce a running load comprises a drum (12), the first and second sliding slant posts (16) and (18) placed at the inlet and outlet sides of the drum (12), the first and second guiding rollers (20) and (22) placed at the outter sides of (16) and (18), the third guiding roller placed on the extension line of the rollers (20) and (22), and the fourth guiding roller (28) and the third sliding slant post (26) which are placed on the downstream side of the tape (14).

Description

Tape odometer of 8mm video cassette recorder

1 is a plan view of a tape traveling system of a conventional M-loading 8 mm VCR deck.

2 is a plan view showing the tape running system of the present invention.

* Explanation of symbols for main parts of the drawings

12: drum 16, 28, 26: sliding sland post

20, 22, 24: guide roller

The present invention relates to a tape running system of a PCM compatible 8 mm video cassette recorder using a 40 mm diameter drum, and more particularly to a tape running system of an 8 mm video cassette recorder capable of reducing a running load of a tape.

The traveling system of the prior art M-loaded 8mm BCR deck has a roller and a sliding post as the traveling elements of the tape, as shown in FIG. In the conventional M-loading traveling system, one sliding sland post (2) 3 is arranged at the entrance and exit side around the drum (1), and guide rollers (4) (5) are arranged at the outside thereof. In order for the tape 6 to be wound on the drum 1 at a predetermined reading angle and a wrapping angle, the tape, which is the initial vertical state, is deformed obliquely through the traveling post and then restored to the vertical state again after passing the drum. In the prior art, since the sliding slant posts are arranged on the inlet and outlet sides of the drum to deform and restore the tape running state, the wrapping angle wound on these sliding slant posts becomes relatively large. In addition, in the case of the roller, the rolling friction occurs with respect to the tape running, and the running part is small, while the sliding post generates sliding friction, thereby increasing the load. The difference in tape tension generated at the entrance and exit side when the tape travels on any sliding post at the wrapping angle θ can be expressed as follows.

ΔT = To (e ^μθ −1)

(Where To is the inlet tape tension and μ is the coefficient of friction between the tape and the post).

That is, ΔT becomes large in proportion to the wrapping angle θ exponentially. Therefore, the most influential factor in comparing and evaluating the load characteristics of various traveling systems is the lapping angle of the sliding post. In the conventional driving system, the lapping angles of the sliding posts are each about 75 ° and the overall latching angle is about 150 °.

In addition, the traveling system of the conventional M-loading system has the advantage of easy configuration of the loading device compared to the traveling system of the U-loading system, while the tape running portion of the traveling system has a large disadvantage. The adverse effect caused by the large running load cannot increase the tape running speed in high speed modes such as FF / REW, and has a lot of power loss in the regeneration mode.

In the present invention has been devised in view of the conventional point as described above in detail with reference to Figure 2 of the accompanying drawings as follows.

In FIG. 2, the drum 12 is disposed in front of the position where the tape cassette 10 is disposed and the first and second sliding slant posts 16 on the entry and exit side of the drum 12 in the path of the tape 14. 18 is disposed and adjacent to the first and second guide rollers 20 and 22 are disposed. According to the invention, a third guide roller 24 is arranged on a line extending the axes of the first and second guide rollers 20, 22 and a third sliding slant downstream thereof on the path of the tape 14. The post 26 and the fourth guide roller 28 are disposed.

The inclination direction of the first to third posts 16, 18 and 26 is indicated by arrows in FIG.

In the present invention, when the rollers and posts of the roller constituting the running system of the tape are inclined, the reading angle and the wrapping angle are listed in the path direction of the tape, the following table (1) shows.

TABLE 1

In the present invention, the direction of the tape 14 is changed as the base surface comes into contact with the first guide roller 20, and the tape 14 is also applied to the first sliding slant post 16 having a leading angle of about 12 °. The tape 14, which has passed through the base surface and has passed through the first post 16, has a magnetic surface with a wrapping range of 221 ° including a predetermined reading angle (4, 885 °) and the PCM area. Winding around The tape 14 exiting the drum 12 is redirected past the first post 18 with a leading angle of 0 ° to the tape, past the second and third rollers 22 and 24, and the third Go through the post 26. The third post 26 raises the tape center lowered up to the third post 26 and contacts the magnetic surface of the tape to wind the tape at a reading angle of about 20 ° to restore the tape to its original state.

The present invention as described above is applicable to a 40 mm diameter drum and will prove to be effective in the odometer of a PCM compatible 8 mm VCR deck.

The traveling system of the present invention has three sliding slant posts and the sum of the latching angles of these posts is about 90 °, which is significantly reduced compared to about 150 ° in the conventional M-loading system. . In addition, since the first roller, the first post, the second post, the second roller, the third roller, etc. contact and load the base surface of the tape, the loading apparatus similar to the conventional M-loading method may be used. In addition, since the third roller is disposed on the extension lines of the first and second rollers, it is expected that there is no problem in space utilization in the deck design.

In addition, in this invention, the 2nd sliding slot post 18 can also be abbreviate | omitted as another embodiment. In this case, the latching angle of the second guide roller should be increased.

Claims (3)

In the arrangement | positioning of the 1st and 2nd sliding-slant posts 16 and 18 on the inlet-outlet side of the drum 12, and arrange | positioning the 1st and 2nd guide rollers 20 and 22 on the outer side, the 2nd The third guide roller 24 is disposed on the extension of the first and second guide rollers 20 and 22 on the downstream side of the guide roller 22 and the third sliding slant post 26 is disposed on the downstream side of the guide roller 22. The tape odometer of the 8mm video cassette recorder, characterized in that it was excreted. The method of claim 1, wherein the leading angle of the first sliding slant post 16 is about 12 degrees, the wrapping angle is about 40 degrees, the wrapping angle of the second post 18 is about 12 degrees, and the third post ( 26) A tape odometer, characterized in that the leading angle of about 20 ° and the latching angle is about 37 °. The tape odometer according to claim 1, characterized in that the second post (18) is omitted and instead the wrapping angle of the second guide roller (22) is increased.