JPS5939354Y2 - Tape usage time display device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tape usage time display device for a cassette type tape recorder, a video tape recorder, etc.

A typical tape recorder is equipped with a counter configured to display a number corresponding to the number of rotations of the supply or take-up reel base, and this counter displays the amount of tape used as a digital amount. ing.

However, although this type of counter is suitable for locating the beginning of the tape using the number displayed on the counter as a guide, it is not possible to accurately know the tape usage time or remaining tape time even by reading the above-mentioned number. It has the disadvantage that it cannot be done.

Therefore, it is often difficult to accurately and immediately judge whether or not a predetermined recording source can be recorded on the remaining portion of the tape based on the display of the counter.

The present invention has been devised in view of the above-mentioned circumstances, and it is an object of the present invention to provide a tape usage time display device that can accurately and immediately read the tape usage time or remaining tape time.

An embodiment in which the present invention is applied to a tape usage time display device in a cassette type tape recorder will be described below with reference to the drawings.

FIG. 1 shows a tape usage time display device 1 (hereinafter referred to as "Pa display device") of this example.

), and this display device 1 has a display drum 3.
A tape running drive system (not shown) is attached to this display drum 3.
and a driving force transmission means 5 for transmitting the driving force from the driving force.

First, the structure of the display device 1 will be explained in detail.
As is clear from the figures and FIG. 4, the base 7 made of synthetic resin or the like is integrally provided with drum support parts 9 and 10 facing each other, and the through holes provided in these support parts 9 and 10 are Both ends of a shaft 3a provided integrally with a display drum 3 made of synthetic resin or the like are inserted into the display drum 3 and rotatably supported.

A worm gear 12 made of synthetic resin or the like is fitted onto the shaft 3a of the display drum 3 in a regulated position between the stepped portion 3b of the shaft 3a and the drum shaft support portion 9. .

The inner cylindrical portion 14 of the worm gear 12 is provided with, for example, three slits 16 as shown in FIGS. 1 and 3, and is divided by the slits 16 into three elastic pieces each having elasticity. 14a, 14b.

Due to the elastic restoring force of 14c, the inner cylindrical portion 14 is fixed to the shaft 3.
It is crimped and fixed to the circumferential surface of a.

However, a rotational force exceeding the degree that occurs between the shaft 3a and the elastic piece 14
a.

14 b y 14 c, they are able to slip against each other against the frictional force acting between them, forming a so-called slip mechanism.

Furthermore, as is clear from FIGS. 1, 2, and 4, the base 7 has a pair of drum supports facing each other in a direction substantially perpendicular to the direction connecting the pair of drum supports 9 and 10. Worm support portions 18.19 are integrally provided, and the longitudinal movement of both ends of the shaft 21a, which is provided integrally with the worm 21 made of synthetic resin or the like, is restricted by these support portions 18.19. It is rotatably supported.

The worm 21 is disposed below the cylindrical body 13 and meshes with the worm gear 12.

A worm gear 23 is integrally molded at one end of the worm 21, and a worm 24 made of synthetic resin or the like and rotatably supported on the base 7 meshes with the worm gear 23.

Further, a pulley 25 is integrally provided at one end of the worm 24 in order to transmit driving force from a tape running drive system (not shown) such as a reel stand drive mechanism to the display device 1, as shown in FIG. As shown in the figure, the rotation of the reel stand 210 is transmitted to the pulley 25 via the belt 26.

Further, as clearly shown in FIG. 1, a scale plate 29 is attached to the circumferential surface of the display drum 30 on which a plurality of tape use time display scale bands 28 are marked according to the type of tape length.

That is, as shown in FIG. 5, the display scale band 28 has time scaled exponentially, for example, 30 minutes, 4 minutes, etc.
When using tape cassettes for 5 minutes, 60 minutes, 90 minutes, and 120 minutes, scale bands 28 corresponding to the tape lengths are provided, and these starting lines (scale markings indicating 0 minutes) are provided. lines) are arranged on the same straight line.

Note that this scale band 28 indicates 5 minutes, 10 minutes, etc. with the starting line as 0 minutes.
......The time is displayed so that it gradually increases to n minutes.

Also, one end of the display drum 3 is provided with anti-slip teeth and has a larger diameter than the display drum 3.
is integrally molded.

As shown in FIG. 4, the operating flange 30 is placed in a state that slightly protrudes outward through an opening 34 provided in the cabinet 32 of the cassette tape recorder main body, and the user can use the operating flange 30 to The display drum 3 is configured to be able to be rotated as required by operating the protruding portion of the display drum 30.

On the other hand, the cabinet 32 is provided with a transparent window 36 marked with marks such as arrows and reference lines so that the boop usage time display scale band 28 provided on the circumference of the display drum 30 can be seen from outside the cabinet. It is being

Next, the operation of the display device 1 configured as described above will be explained together with the operating procedure.

First, a tape cassette having a desired tape usage time is loaded into the tape recorder main body, the tape recorder main body is switched to the REW mode, and the entire tape is wound onto the supply reel side.

Thereafter, the display drum 3 is set by rotating the operating flange 30 of the display drum 3 with a fingertip, for example, in the direction of arrow A or E in FIG.

That is, the display drum 3 has a worm gear 12 and a worm 21.
Although the rotation is prevented by the engagement with the worm gear 120, when a rotational force is applied to the operating flange 30, the elastic pieces 14 a y 14 b, 14 of the worm gear 120
Only the display drum 3 is rotated in the direction of the arrow A or E against the pressing force (frictional holding force) acting between the display drum 30 and the shaft 3a of the display drum 30.

Therefore, the display drum 3 is rotated by the operation described above to align the starting line of the scale band 28 with the arrow or reference line of the transparent window 36.

In other words, the scale band 28 is reset to the starting position.

In this case, 30 revolutions of the display drum is caused by the worm gear 12.
The reel stand 2 is
7, the display drum 3 can be reliably reset to the start position without any adverse effect on the tape.

Next, switch the tape recorder main body to FWD mode.

As a result, the tape running drive system is activated, and the reel stand 2
7 rotates in the direction of arrow B in FIG.

As a result, 270 rotations of the reel stand are transmitted to the pulley 25 via the belt 26 and L7.

As the reel stand 270 rotates, the worm 24 and worm gear 23 constituting the first reduction mechanism rotate in the directions indicated by arrows C and D in FIG. 1, thereby decelerating the rotation of the reel stand H. and is transmitted to the second worm 21.

Then, the worm 21 and the worm gear 12, which constitute the second speed reduction mechanism, rotate in the directions shown by arrows and E in FIG.
It is further transmitted to the worm gear 12 by the speed reduction mechanism.

As a result, the display drum 3 has elastic pieces 14a and 14b.

The worm gear 12 is rotated together with the worm gear 12 in the direction of the arrow E by the pressing force (frictional engagement force) acting between the shaft 14c and the shaft 3a.

That is, at this time, the elastic pieces 14 a y 14 b y
14c and the shaft 3a of the display drum 3, the display drum 3 and the worm gear 12 rotate together in accordance with the number of revolutions of the reel stand 270 without slipping between them.

When the user wants to know the tape usage time or remaining tape time, the user looks into the transparent window 36 and corresponds to the type of tape length among the scales on the display drum 3 indicated by the indication line of the transparent window 36. If you read the scale on the scale band 28,
The read value is the tape usage time.

Note that the remaining tape time can be easily determined by subtracting the usable time of the tape from the tape usage time according to the type of tape length.

Although the present invention has been described above with reference to one embodiment, the present invention is not limited to this embodiment, and various modifications can be made based on the technical idea of the present invention.

For example, if the scale of the scale band 28 is reversed to that shown in the embodiment, and it is a C-60 tape cassette, the starting line is set to 60 minutes, which is the maximum time, and 50.40...・
If the time is displayed so as to gradually decrease from 0 minutes, the remaining tape time can be displayed using this scale band 28.

Further, the slip mechanism provided between the shaft 3a of the display drum 3 and the worm gear 12 can be changed to various configurations.

Furthermore, in this embodiment, first and second deceleration mechanisms each consisting of a worm 21.24 and a worm gear 12.23 are provided in order to decelerate the rotation of the reel stand 27 and transmit it to the display drum 3. The number of such speed reduction mechanisms may be increased or decreased as necessary.

Further, it is not always necessary to obtain the driving force from the tape running drive system from the reel stand 27. For example, the driving force may be obtained from the rotating shaft of a motor for driving the reel stand or a capstan. Good too.

It goes without saying that the present invention is also applicable to video tape recorders and the like.

As mentioned above, the present invention includes a worm that is rotationally driven by the driving force from the tape running drive system, a worm gear that is meshed with the worm at right angles and is rotationally driven by the worm, and a shaft that is integrally provided at the center. A display drum, a slip mechanism integrally provided on the inner periphery of the worm gear and frictionally engaged with the outer periphery of the shaft, and a plurality of tapes provided on the outer periphery of the display drum depending on the type of tape length. It consists of a time display scale band and an operation flange having a larger diameter than the display drum, which is integrally provided at one end of the display drum, and the display drum is rotated by the large diameter operation flange, and the display drum is rotated. The display drum is configured to slip with respect to the worm gear by the slip mechanism while the worm gear is stopped by the worm when the display drum is set to the start position. This is configured so that the signal is not transmitted to the tape running drive system.

Therefore, according to the tape usage time display device of the present invention, the tape usage time and tape remaining amount time can be read accurately and instantly according to the type of tape length, which is very convenient.

In particular, there is a great practical advantage in that it can be reliably determined whether or not a predetermined recording source can be recorded on the tape that one actually wants to use.

In addition, by effectively utilizing the self-locking function created by the engagement between the worm and the worm gear, only the display drum is allowed to slip using the slip mechanism while the worm is stopped, so the display drum is rotated to start the tape usage time display scale band. Can be easily reset to position.

Moreover, since the worm is completely stopped at this time, even if the frictional engagement force of the slip mechanism is made extremely strong, the rotational force of the display drum is never transmitted to the tape running drive system.

Therefore, the resetting operation of the display drum will not cause the tape to unexpectedly shift and cause wrinkles, cuts, etc., and the resetting operation can be performed reliably without any trouble.

In addition, since the frictional engagement force of the slip mechanism can be made extremely strong, when the display drum is rotated by the driving force from the tape running drive system, the display drum will not slip against the worm gear at all, and the display There is no chance of the drum being misaligned and causing an inaccurate tape usage time display.

However, when the display drum is rotated to perform a reset operation, the display drum can be rotated lightly by the operating flange having a diameter larger than that of the display drum, so the reset operation can be easily performed.

In addition, multiple tape use time display scale bands are provided on the outer periphery of the display drum according to the type of tape length, so the display part of the scale band (for example, a transparent window in a cabinet) can be formed using a narrow slit with an extremely small area. It also has a good appearance and appearance.

[Brief explanation of drawings]

The drawings show an embodiment of a tape usage time display device in a cassette type tape recorder according to the present invention, in which FIG. 1 is a perspective view of the display device, and FIG. 2 is a partially cutaway plan view of the display device. , FIG. 3 is a sectional view taken along the line M-■ in FIG. 2, FIG. 4 is a front view of the display device, and FIG. be. In addition, in the symbols used in the drawings, 1...
・Tape usage time display device, 3...Display drum, 5...Driving force transmission means, 12, 23...
...Worm gear, 14a-14c...Elastic piece, 16...Slit, 21, 24...
・Worm, 27...Reel stand, 28...
... Tape usage time display scale band, 3a ... Axis of display drum, 30 ... Operation flange.

Claims (1)

[Scope of utility model registration request] A worm rotatably driven by the driving force from the tape running drive system, a worm gear meshed with the worm at right angles and driven by the worm, and a display drum integrally provided with a shaft in the center; a slip mechanism integrally provided on the inner periphery of the worm gear and frictionally engaged with the outer periphery of the shaft; and a plurality of tape usage time display scale bands provided on the outer periphery of the display drum according to the type of tape length. , an operating plunger having a diameter larger than that of the display drum, which is integrally provided at one end of the display drum, and the display drum is rotated by the large diameter operating flange to set the scale band at the starting position. When operating, the display drum is configured to be caused to slip with respect to the worm gear by the slip mechanism while the worm gear is stopped by the worm,
A tape usage time display device configured such that rotational force of the display drum is not transmitted to the tape running drive system.