JPH048494Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is equipped with a tape end detection device that detects the end of the tape by mechanically detecting the stoppage of rotation of the reel shaft, and automatically returns to the stopped state upon detection of the end of the tape. The present invention relates to a magnetic recording/reproducing apparatus configured as described above, and particularly to a magnetic recording/reproducing apparatus characterized in that a tape end detection device is prevented from malfunctioning.

A tape end detection device that detects the end of a tape by mechanically detecting the stoppage of rotation of a reel shaft is generally constructed as shown in FIG.
That is, 1 is rotatably pivoted to the take-up reel shaft 2,
This is a detection lever that is shifted in the rotational direction of the take-up reel shaft 2, and has an arrow-shaped groove 3 formed at its tip. 4 is a cam gear driven by a motor (not shown), and as shown in FIG. 2, cams 5 and 6 are formed and cam grooves (A), (B), and (C) are formed. Reference numeral 7 denotes a release lever which is pivotally supported at the center by a chassis shaft 8 and biased counterclockwise by a spring 9, as well as projecting pins 10 and 11 implanted above and below one end as shown in FIG.
is engaged with the arrow-shaped groove 3 and cam groove of the detection lever 1, and the other end faces a position where it engages with a locking plate 12 that locks the operating lever.

Therefore, when the take-up reel shaft 2 is rotated and the tape is running, the detection lever 1 receives the counterclockwise rotational force of the take-up reel shaft 2, and is shifted counterclockwise, thereby causing the detection lever 1 to act on the cam gear. 4, the upper projecting pin 10 of the release lever 7 is reciprocated along the oblique side of the arrow-shaped groove 3 of the detection lever 1, so that the lower projecting pin 11 moves through the cam groove of the cam gear 4 into the fourth and fourth cam grooves. As shown in Figure 5, it is moved along the route A→B→A. Therefore, the other end of the release lever 7 is moved back and forth between the first and second positions as shown in FIGS. 4 and 5, and is not engaged with the locking plate 12.

However, when the tape reaches the end and the rotation of the take-up reel shaft 2 is stopped, the rotational force is no longer applied to the detection lever 1 as shown in FIG. arrow shaped groove 3
The release lever 7 is rotated largely counterclockwise to the first position by entering the long groove C of the cam gear 4 and the lower protrusion pin 11 entering the cam groove C of the cam gear 4. By engaging with the lock plate 12 and moving the lock plate 12 to the right, the control lever is unlocked and shifted to the stopped state.

In this way, the end of the tape is detected and the stopped state is restored. However, depending on the positional relationship between the detection lever 1 and the projecting pin 10 of the release lever 7 at the time of returning to the stopped state, a play operation may be performed next. There was a problem in that when the tape end detection device was activated by mistake, the tape end detection device was immediately returned to the stopped state. That is, when the stopped state is restored, the detection lever 1 is in a position where it is not displaced as shown in FIG. If the arrow-shaped groove 3 is stopped while moving in the long groove direction, the next time a play operation is performed and the take-up reel shaft 2 and cam gear 4 are rotated, the detection lever 1 detects the rotational force of the take-up reel shaft 2. Before the release lever 7 is deflected counterclockwise, the upper projecting pin 10 of the release lever 7 is moved into the long groove of the arrow-shaped groove 3 of the detection lever 1, so that the release lever 7 is moved to the position as described above. The play bar was moved until it was unlocked and returned to a stopped state.

Therefore, the present invention has been made to improve the above-mentioned drawbacks, and provides a magnetic recording/playback device that prevents the tape end detection device from malfunctioning by forcibly shifting the detection lever when the tape end is returned to the stopped state. It is something to do.

Embodiments of the present invention will be described below with reference to the drawings.
Note that the same components as in FIG. 1 are indicated by the same figure numbers. 1
Reference numeral 3 denotes a detection lever control plate rotatably mounted on the detection lever 1 mounted on the take-up reel shaft 2, which is biased counterclockwise by a spring 14 and has a control pin 15 projecting downward. is brought into contact with one side of the detection lever 1, thereby acting to forcibly rotate the detection lever 1 in the counterclockwise direction. 16 is slid in the direction of the arrow by the play operation, comes into contact with the protruding shaft 17 installed at one end of the detection lever control plate 13, and rotates the detection lever control plate 13 clockwise against the bias of the spring 14. The first sliding plate 18 is slid in the direction of the arrow by fast forwarding or winding operation, and comes into contact with a protruding shaft 19 installed at the other end of the detection lever control plate 13, and the detection lever control plate 13 is moved by the spring 14. This is a second sliding plate that is rotated clockwise against the urging force of the second sliding plate.

Next, the operation of the present invention having such a configuration will be explained.

When a play operation is performed and the tape is running, the first sliding plate 16 comes into contact with the protruding shaft 17 of the detection lever control plate 13, as shown in FIG. By rotating clockwise against the force, the detection lever control plate 13
Since the control pin 15 is separated from the detection lever 1, the detection lever 1 performs the aforementioned detection operation without being restricted in any way by the control pin 15, and the release lever 7 is reciprocated between the first position and the second position. There is.

Next, when a fast forwarding or winding operation is performed, the second sliding plate 18 slides in the direction of the arrow as shown in FIG. 19 and rotates the detection lever control plate 13 clockwise against the bias of the spring 14, the detection lever 1 performs the detection operation without being restricted in any way as in the case of the play operation.

Therefore, when the end of the tape is detected as described above during play, fast forwarding or rewinding and the tape is returned to the stopped state, the first or second sliding plates 16, 18
is also returned to its initial position, and the detection lever control plate 13 is disengaged from the protruding shafts 17 and 19, whereby the detection lever control plate 13 is rotated counterclockwise under the bias of the spring 14, and the detection lever control plate 13 is rotated counterclockwise under the force of the spring 14. As shown in FIG. 8, the control pin 15 comes into contact with one side of the detection lever 1, forcing the detection lever 1 to rotate counterclockwise.

Therefore, even if the next play operation or the like is performed and the projecting pin 10 above the release lever 7 is moved in the direction of the long groove of the arrow-shaped groove 3 of the detection lever 1, the projecting pin 10 will move along the oblique side of the arrow-shaped groove 3. Since the player is moved along with the player and never enters the long groove, the automatic stop is activated immediately after the play operation as described above, and the player is not returned to the stopped state.

As mentioned above, the magnetic recording/playback device of the present invention is configured to forcibly shift the detection lever of the tape end detection device in the stopped state.
When a play operation or the like is performed from a stopped state, it is possible to prevent the tape end detection device from malfunctioning. Furthermore, since the detection lever control board and the detection lever are coaxially provided on the reel shaft, the storage space required for the detection lever control board can be minimized, thereby providing a practically useful magnetic recording and reproducing device. be able to.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional example of a magnetic recording and reproducing device.
Figure 2 is a diagram showing the configuration of the main parts in Figure 1, Figure 3 is a sectional view of the main parts in Figure 1, and Figures 4, 5, 6, and 7 are the operating states of Figure 1. Figures 8 and 9 showing
The figure shows the configuration of the magnetic recording and reproducing device of the present invention.
10 and 11 are diagrams showing the operating state of FIG. 8. 1...Detection lever, 2...Reel shaft, 4...Cam gear, 7...Release lever, 12...Lock plate, 1
3...Detection lever control board.

Claims (1)

[Scope of utility model registration request] In a magnetic recording and reproducing device comprising a tape end detection device that has a detection lever attached to a reel shaft and is shifted by the rotational force of the reel shaft, and detects the end of the tape by detecting the stoppage of rotation of the reel shaft, the detection lever A magnetic recording and reproducing device comprising a detection lever control plate that is mounted coaxially on a reel shaft, forcibly shifts the detection lever in a stopped state, and releases the shift by a play operation or the like. .