JPH0510741B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cassette for measuring the tape drive capability of a recording/reproducing apparatus using magnetic tape.

[Problems to be solved by conventional technology and invention]

When testing the tape driving ability of a pinch roller and capstan in a cassette tape recorder, apply a predetermined amount of back tension to the tape and run the tape with the pinch roller and capstan in this state. , to see if the tape runs normally. For this test, a tape drive ability measuring cassette, which is a modified ordinary tape cassette, is used. This measurement cassette stores a tape on which a reference signal of, for example, 3 KHz is recorded, and is also provided with a mechanism for applying a predetermined back tension to the tape. This cassette is played back by the tape recorder to be tested, and wow and flutter are checked from the played reference signal, and the tape drive ability is determined based on the degree of wow and flutter.

As a mechanism for applying back tension, the supply reel has a double structure consisting of an inner ring fixed to the cassette and an outer ring around which the tape is wound, and a magnetic hysteresis mechanism or a spiral spring is installed between the inner ring and the outer ring. Interpose a means for applying a load torque,
When the outer ring rotates in the tape feeding direction, the above means biases the outer ring in the opposite direction to provide back tension. When the measurement cassette is attached to the tape recorder, the supply reel shaft is inserted into the inner ring. During playback, the inner ring is fixed to the cassette, but when rewinding, it is released and the inner and outer rings are rotated by the reel shaft to wind up the tape. For this purpose, the cassette is provided with an inner ring locking mechanism.

Conventionally, locking and unlocking were performed by manually operating the locking mechanism, but since playback and rewinding were frequently repeated during the inspection, the operation became complicated and the operation was sometimes forgotten.

[Means for solving problems]

In the present invention, a supply reel and a take-up reel on which a tape on which a reference signal is recorded are respectively wound are housed in a cassette housing, and the above-mentioned supply reel has an inner ring into which a supply-side reel shaft is inserted and the above-mentioned tape. A means for applying a predetermined load torque to the outer ring when the outer ring rotates in the forward direction is interposed between the outer ring and the inner ring, and a means for applying a predetermined load torque to the outer ring when the outer ring rotates in the forward direction. A wire stop spring is fixed to the incisal edge of the reel shaft insertion hole and extends freely within the hole, and a protrusion is provided on the surface of the inner ring that faces the stop spring extension. When the outer ring is rotated in the forward direction, the protrusion engages with the protrusion to prevent the inner ring from rotating, thereby preventing the complicated operation or forgetting the operation. The aim is to eliminate the deficiencies of

〔Example〕

The embodiments of the present invention will be described with reference to the drawings.
In the figure, reference numeral 1 is a cassette which is a modified Phillips type tape cassette, and mainly contains an upper half 2a, a lower half 2b, a supply reel 3, a take-up reel 4, and a tape 5. A reference signal of, for example, 3KHz is recorded on the tape 5, and the upper and lower halves 2a and 2b have reel shaft insertion holes 7 and 8, an erasing head or pinch roller insertion window 10, a recording/playback head insertion window 11, and a pair of capstans, respectively. Insertion hole 12
Further, the lower half 2b is provided with a pair of guide rollers 9, a leaf spring 14 to which a pad 15 is fixed, and a shield plate 13 to which the leaf spring 14 is attached.
etc. are provided. The take-up reel 4 is provided with a take-up reel shaft insertion hole 18 . The supply and take-up reel shaft insertion holes 17 and 18 each have six holes.
pins 20 (not shown in the insertion hole 17)
is provided, and the pin 20 is inserted into the insertion hole 17,1.
The rotation of each reel shaft is transmitted to each reel 3 and 4 by engaging with a recess formed around the tip of the reel shaft inserted into the reel shaft 8 . The supply reel 3 is composed of an outer ring and an inner ring, which will be described later. After storing the reels 3, 4 and tape 5, the upper and lower halves 2a and 2b are fitted together and fastened with screws 21 at five locations in total, including the four corners and approximately the center of the front.

The above-mentioned supply reel 3 is composed of an outer ring 3a and an inner ring 3b, and the inner ring 3b is composed of a first ring 3b ₁ and a second ring 3b ₂ , respectively, and the first ring 3b ₁ and the second ring 3b ₂ are formed by a support plate. 22. The second wheels 3b ₂ each have a ring-shaped elastic body 2 such as rubber.
3. It has a structure in which a main body 24, a yoke 25, a magnet 26, etc. are stacked as shown. The magnet 26 is magnetized with six magnetic poles N and S, as shown in FIG. The first wheel 3b ₁ is provided with a protrusion 42 (described later), the pin 20 described above, and the reel shaft insertion hole 17 described above, and further has a flange 27 formed therein. This flange 27 is provided with a screw hole 28 into which an adjustment screw 29 is screwed. The tip of this adjustment screw 29 is in pressure contact with the main body 24, and by tightening or loosening it against the elasticity of the elastic body 23, the magnet 2
6 is adjusted in the vertical direction, thereby adjusting the distance d between the magnet 26 and a hysteresis plate 31, which will be described later.

The outer ring 3a is formed into an inverted dish shape, and a winding portion 32 of the tape 5 is provided on the outer side. This outer ring 3a
A protrusion 42, which will be described later, is fitted into the center hole 38 of the ring 3 and is rotatable around the inner ring _3b1 . A hysteresis plate 31 is provided on the lower surface of this outer ring 3a.
is fixed to the magnet 26 at a distance d. Further, insertion holes 35 and 36 for screwdrivers and the like are provided in the outer ring 3a and the upper half 2a, facing the screw holes 28. A sheet 39 having excellent lubricity is placed on the inner surface of the lower half 2b.

Furthermore, the above-mentioned supply reel 3 has the above-mentioned inner ring 3.
A ring upper protrusion 42 forming a part of b is provided. This protrusion 42 communicates with the supply reel shaft insertion hole 17, and has slopes 43a, 44 on its end surface 42a.
Protrusions 43, 44 with a are formed. Also, the supply side reel shaft insertion hole 7 of the upper half 2a
A pair of slots 45 and 45' are provided on the incisal edge of the hole 7 so as to face each other on a line passing through the center point of the hole 7. Inside these slots 45, 45', there is a stop spring 47 made of round wire, which is provided with a semicircular or completely circular bent part 46 in the middle, which has a detour function and a flexibility imparting function. 48, 48' are inserted into the stop spring 47, and curved stop legs 49, 49' extend from both ends of the stop spring 47. Recessed grooves 50, 50' provided on the lower surface of the incisal edge of the hole 7
and are irremovably fitted into the insertion holes 51, 51'. The linear portions 48, 48' on both sides of the stop spring 47 always return within the rotation locus of the projections 43, 44, forming the one-way clutch mechanism 16 as shown in FIG.

[Effect]

Since the present invention has the above-described configuration, when the cassette 1 is attached to the tape recorder and the supply side reel shaft 53 is inserted into the reel shaft insertion holes 7 and 17 as shown by the imaginary line in FIG. Each pin 19 is engaged with a recess formed at the tip of this reel shaft 53. When the take-up reel shaft (not shown) is driven in this state and the supply reel 3 is driven in the forward direction (tape feeding direction), the protrusion 42
is driven in the direction of arrow a in FIGS. 1 and 4. At this time, as shown in FIG.
8', the protrusion 42, i.e. the first
Rotation of the ring _3b1 is prevented, so that the inner ring 3b cannot rotate.

Further, when the reel shaft 53 is rotated in the unwinding direction, this rotation is transmitted to the inner ring 3b via the pin 20, so that the protrusion 42 rotates in the direction of arrow b in FIGS. 1 and 5. In this case, in FIG. 5, the linear portions 48 on both sides of the stop spring 47,
Since the inner ring 3b moves in the direction b while elastically contacting the slopes 43a and 44a of the protrusions 43 and 44, the inner ring 3b can rotate in the unwinding direction.

Also, when the outer ring 3a rotates in the forward direction, the second
In the figure, hysteresis loss occurs in the hysteresis plate 31, and the attractive force due to residual magnetism is applied to the magnet 2.
6. As a result, a predetermined load torque is applied to the outer ring 3a, which acts as a back tension for the tape 5. Further, when the inner ring 3b is unlocked and rotates in the rewinding direction, the inner ring 3b and the outer ring 3a rotate integrally due to the suction force of the magnet 26 against the hysteresis plate 31, and the tape 5 is wound up.

FIG. 6 shows how the measurement cassette 1 constructed as described above is used.

The cassette 1 is mounted on a tape recorder, and the reel shafts 53 and 54 are inserted into the reel shaft insertion holes 7 and 8, respectively. At the same time, a reproducing head 55, a pinch roller 56, and a capstan 57 are inserted into predetermined positions within the cassette 1.

When the reproduction mode is entered in this state, the tape 5 is run in the direction of arrow d by the pinch roller 56 and capstan 57. At this time, as described above, the inner ring 3b is fixed, and the outer ring 3a rotates while being given a predetermined back tension. By measuring wow and flutter from the reference signal reproduced by the head 55, the tape driving ability of the pinch roller 56 and capstan 57 is determined.
When the tape 5 reaches the tape end during measurement, the reel shaft 54 is driven to perform rewinding. During rewinding, the inner ring 3b and outer ring 3a rotate together to wind up the tape 5 as described above.

〔Effect of the invention〕

Since the present invention is as described above, it is not necessary to manually release the lock on the inner ring each time the tape is rewound as in the conventional case, and it can be handled in the same way as a normal cassette, thereby increasing the efficiency of measurement work. Not only does it have an excellent effect of fully achieving the purpose of eliminating defects such as complicated operations and forgetting operations, but also the present invention provides a supply side reel shaft. There is an advantage that the stop spring can be fixed to the incisal edge of the insertion hole by simple means such as slotting and fitting into the groove as in the embodiment, and the stop spring can be easily made of wire. It is possible to do so and has effects such as being economically advantageous.

[Brief explanation of drawings]

The figures show an embodiment of the tape drive ability measuring cassette of the present invention, in which Fig. 1 is an exploded perspective view of the whole, Fig. 2 is a sectional side view of the main parts, Fig. 3 is a plan view of the magnet, 4 and 5 are side views of the clutch mechanism, FIG. 6 is a plan view of the clutch mechanism in use, and FIG. 7 is a perspective view showing another type of stop spring. 1...Measurement cassette, 3...Supply reel, 3
a... Outer ring, 3b... Inner ring, 4... Take-up reel, 5... Tape, 7, 17... Reel shaft insertion hole, 16... Unidirectional clutch mechanism, 43, 44
...Protrusion, 47...Stop spring.

Claims (1)

[Claims] 1. A supply reel and a take-up reel, around which the tape on which the reference signal is recorded, are respectively wound, are housed in a cassette housing, and the above supply reel has an inner ring into which the supply reel shaft is inserted, and an inner ring around which the above tape is wound. A means for applying a predetermined load torque to the outer ring when the outer ring rotates in the forward direction is interposed between the outer ring and the inner ring, and means for applying a predetermined load torque to the outer ring when the outer ring rotates in the forward direction. A wire stop spring is fixed to the incisal edge of the insertion hole and extends freely into the hole, and a protrusion is provided on the surface of the inner ring facing the stop spring extension. 1. A cassette for measuring tape driving ability, characterized in that when the outer ring of the cassette is rotated in a forward direction, the protrusion engages with the protrusion to prevent the inner ring from rotating.