JPH02249164A - Reel base - Google Patents

Abstract

PURPOSE:To realize a high response tension servo for a running tape driven by a reel motor by fitting a tape reel on a reel base by bitting plural driving bosses protruded in plural reel grooves at their tapered area. CONSTITUTION:The reel base is provided with the tapered part 22 in which either the plural driving bosses 21 provided at the outer periphery of the central axis part of the reel base 1 main body with equal intervals are freely inserted in and out with a certain stroke and pressed in an outer peripheral direction, or the plural reel grooves 23 provided at the inner periphery of the center hole of the tape reel 8 is converged in the outer peripheral direction on a plane perpendicular to the central axis part. And also, it is comprised in such a way that the plural driving bosses 21 protruded in the plural reel grooves 23 are set in the plural reel grooves 23 at the tapered part 22, and the tape reel 8 can be fitted on the reel base main body 1. Therefore, it is possible to rotatably drive the tape reel 8 integrally with the reel base 1 by the plural driving bosses 21 without generating slippage between the reel base 1 and the tape reel 8. Thereby, the tension servo for the running tape with high response can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a reel stand used in a magnetic recording/reproducing device such as a video tape recorder.

BACKGROUND OF THE INVENTION In recent years, various types of video tape recorders have been developed, and among these, efforts have been made to further improve the operability of stationary models used for recording and playback. Therefore, even in high-speed tape search functions, etc., it is required to perform tension servo to prevent over-tension from being applied to the tape during the tape running transition period.
Accordingly, there is a need for a reel stand that rotationally drives the tape reel to have a mechanism that enables tensile servo with higher responsiveness.

A first example of a conventional reel stand will be described below.

FIG. 3 is a cross-sectional view showing how a tape reel is attached to a reel stand in the first conventional example, and FIG. 4 is a vertical cross-sectional view thereof. In Figures 3 and 4,
1 is a reel stand. 2 is a reel stand body on a disk. Reference numeral 3 denotes a central shaft portion, which is integrally formed perpendicularly to the center of the reel stand main body 2. 4 is multiple (three in this conventional example)
These drive pawls are arranged at equal intervals around the outer circumference of the central shaft part 3, and are capable of moving in and out of the central shaft part 3 by a fixed stroke (S) in the radial direction of the central shaft part 3, and are normally biased by a spring 5. and protrudes from the outer periphery of the central shaft portion 3. Reference numeral 6 denotes a motor shaft of a reel motor (not shown), which rotationally drives the reel stand 1 consisting of the reel stand main body 2, the central shaft portion 3, a plurality of drive claws 4, and a spring 5. 7 is a tape cassette mounted on the reel stand 1, 8 is a tape reel in the tape cassette 7, 9 is a center hole of the tape reel 8, and 10 is a center hole 9
A plurality of (9 in this conventional example) formed at equal intervals on the inner circumference of the
The reel grooves 11 are a plurality of driven pawls forming the reel groove 10.

Note that the number of these plurality of reel grooves 1o is an integral multiple of the number of plurality of drive claws 4 of the reel stand 1.

Further, 12 is an annular convex portion formed on the lower surface of the tape reel 8, 13 is a magnetic tape wound around the tape reel 8, 14 is a lower half of the cassette 7, and 15 is an upper half 14. A leaf spring is used to press the tape reel 8 against the reel stand main body 2 or the lower half 16.

The operation of the first example of the conventional reel stand configured as described above will be described below.

When the tape cassette 7 is mounted on the reel stand 1, the center hole 9 of the tape reel 8 is inserted into the center shaft part 3 of the stand 1, and as shown in FIG. The driving claws 4 are urged in the outer circumferential direction by the spring 5, so that they protrude within the plurality of reel grooves 10 formed on the inner circumference of the center hole 9. At the same time, as shown in FIG. 4, the annular convex portion 12 formed on the lower surface of the tape reel 8 is pressed against the upper surface of the reel stand main body 2 by the spring force of the leaf spring 15. When attaching the tape reel 8 to the reel stand 1, after the annular convex portion 12 on the lower surface of the tape reel 8 comes into contact with the upper surface of the reel stand main body 2, the lower surface of the lower half 16 is further pressed by a certain amount into a stopper (not shown). As the tape cassette 7 descends until it comes into contact with the leaf spring 15, the tape reel 8
The tape reel 8 floats a certain amount above the lower half 1e against this, and the lower half 16 and the tape reel 8 can rotate without contacting each other. When the reel stand 1 is rotated by the motor shaft 6 of a reel motor (not shown), the tape reel 8 is moved to the reel stand 1 by the plurality of drive claws 4 protruding within the plurality of reel grooves 10 of the tape reel 8. It is rotated as one unit.

On the other hand, when the center hole 9 of the tape reel 8 is inserted into the center shaft part 3 of the reel stand 1, the phases of the plurality of reel grooves 10 and the plurality of drive claws 4 are shifted, as shown by the dashed line in FIG. Then, the plurality of driving claws 4 are pushed into the central shaft portion 3 by the plurality of driven claws 11 against the spring 5, and in this state, the annular convex portion 12 of the tape reel 8 is brought into close contact with the upper surface of the reel stand main body 2. be done. When the reel stand 1 is rotated by the motor shaft 6, the annular convex portion 12 of the tape reel 8 slides relatively on the reel stand main body 2, and the plurality of drive claws 4 protrude between the plurality of reel grooves 10. do.

Next, a second example of a conventional reel stand will be explained.

FIG. 5 is a longitudinal cross-sectional view showing how the tape reel is mounted on the reel stand of the first conventional example, and the cross-sectional view is a cross-sectional view showing the same cross-sectional view of the first example. It is the same as Figure 3.

The difference from the first example of the conventional reel stand is that an annular high-friction member 1 made of rubber or the like is provided on the outer periphery of the upper surface of the reel stand main body 2.
7 is fixed, and the rest is the same as the first example of the conventional reel stand.

The operation of the second example of the conventional reel stand configured as described above will be described below.

When the tape cassette 7 is mounted on the reel stand 1, the center hole 9 of the tape reel 8 is inserted into the center shaft portion 3 of the reel stand 1, and the center hole A plurality of drive pawls 4 arranged on the outer periphery of the center hole 9 protrude within a plurality of reel grooves 10 formed on the inner periphery of the center hole 9. As shown in FIG. It is crimped by force. When installing the tape reel 8 on the reel stand 1, the tape reel 8 is placed on the top surface of the high friction member 17.
After the annular protrusion 12 on the lower surface contacts, the tape cassette 7 further descends by a certain amount until the lower surface of the lower half 16 contacts a stopper (not shown), so that the tape reel 8 resists the leaf spring 15. The tape reel 8 floats a certain amount above the lower half 16, and the lower half 16 and tape reel 8 can rotate without contacting each other. When the reel stand 1 is rotated by the motor shaft 6 of a reel motor (not shown), the tape reel is moved by the plurality of drive pawls 4 protruding within the plurality of reel grooves 10 of the tape reel 8 and the high friction member 17. 8
is rotated integrally with the reel stand 1.

Problem to be Solved by the Invention However, in the above conventional configuration, in the first example, the torque of the reel motor (not shown) is transferred to the tape reel 8.
The signal is transmitted to the tape reel 8 by the plurality of drive claws 4 of the reel stand 1 that protrude within the plurality of reel grooves 10, and the drive claws 4 are designed to smoothly enter the plurality of reel grooves 10. Due to dimensional tolerance, the width l of the plurality of drive claws 4 and the width of the plurality of reel grooves 10 are L −1=0
．． The dimensions are such that there is a clearance of around 8mm.

Therefore, if an attempt is made to transmit a force greater than the frictional force between the annular convex portion 12 on the lower surface of the tape reel 8 and the upper surface of the reel stand main body 2 from the reel motor (not shown) to the tape reel 8, the reel stand 1 Slippage occurs between the tape reel 8 and
The plurality of drive claws 4 are now in a state where they can freely move within the range of clearance (L-1) within the plurality of reel grooves 10, and the torque generated in the reel motor (not shown) is reliably transferred from the reel stand 1 to the tape reel 8. Therefore, there was a problem in that the reel motor (not shown) could not perform tension servo with high responsiveness on the running tape.

In the second example, an annular high-friction member 17 made of rubber or the like is fixed to the outer periphery of the upper surface of the reel stand main body 2 to prevent slippage between the reel stand 1 and the tape reel 8. In this way, the torque of the reel motor (not shown) is transmitted to the tape reel 8 by the plurality of drive claws 4 and the high friction part side 17 of the reel stand 1. It is necessary to fix the high friction member 17 to the upper surface, and when the center hole 9 of the tape reel 8 is fitted to the center shaft portion 3 of the reel stand 1, a plurality of reel grooves are formed as shown by the dashed line in FIG. 10 and the plurality of drive claws 4, the plurality of drive claws 4 are pushed into the central shaft portion 3 by the plurality of driven claws 11 against the spring 5, and in this state, the annular shape of the tape reel 8 is The convex portion 12 is in close contact with a high friction portion side 17 fixed to the upper surface of the reel stand main body 2. Therefore, by rotating the reel stand 1 and sliding the annular convex portion 12 relatively against the frictional force on the high friction portion side 17, the plurality of driving claws 4 can be made to protrude within the plurality of reel grooves 10. However, there is a problem in that torque transmission from the reel stand 1 to the tape reel 8 is performed only by the high-friction member 17.

In view of the above conventional problems, the present invention provides a reel stand that can reliably transmit the torque of the reel motor from the reel stand to the tape reel and perform highly responsive tension servo of the running tape by the reel motor. With the goal.

Means for Solving the Problems To achieve this object, the reel stand of the present invention has a plurality of drive pawls provided on the outer periphery of the central shaft portion of the reel stand body and a plurality of drive claws provided on the inner periphery of the center hole of the tape reel. At least one of the reel grooves has a tapered part that tapers in the outer circumferential direction on a plane perpendicular to the central axis, and a plurality of drive claws protruding into the plurality of reel grooves have a plurality of drive pawls in the tapered part. The tape reel is configured to fit onto the reel stand main body by coming into contact with the reel groove.

According to the above-described configuration, the present invention has a shape in which at least one of the plurality of drive pawls and the plurality of reel grooves has a tapered portion that tapers in the outer circumferential direction on a plane perpendicular to the central axis, and the plurality of reels The plurality of drive claws protruding within the groove abut the plurality of reel grooves at the tapered portion, thereby fitting the tape reel onto the reel stand without any clearance, and preventing slippage between the reel stand and the tape reel. and
It is possible to reliably transmit the torque of the reel motor from the reel stand to the tape reel, and to perform highly responsive tension servo on the running tape by the reel motor.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing how a tape reel is attached to a reel stand in an embodiment of the present invention, and FIG. 2 is a longitudinal cross-sectional view of the same.

Note that the same components as in the conventional example are given the same numbers and detailed explanations thereof will be omitted.

1 and 2, reference numeral 21 indicates a plurality of (three in this example) drive claws with a constant stroke (S
'), and is normally biased by a spring 5 and protrudes toward the outer circumference.

Reference numeral 22 denotes a tapered portion formed on the plurality of driving claws 21 so as to taper in the outer circumferential direction on a plane perpendicular to the central shaft portion 3, and reference numeral 23 denotes a plurality of (nine in this embodiment) glue-R grooves. can be,
24 is a plurality of driven pawls forming a plurality of reel grooves 23; 25 is a plurality of driving pawls 21 within the plurality of reel grooves 23;
These are the large corner portions of the plurality of reel grooves 23 that come into contact with the tapered portion 22 when the grooves protrude.

Regarding the reel stand of this embodiment configured as above,
The operation will be explained below.

When the tape cassette 7 is installed on the reel stand 1, the center hole 9 of the tape reel 8 is inserted into the center shaft part 3 of the reel stand 1, and the tape reel 8 is placed on the outer periphery of the center shaft part 3 as shown in FIG. A plurality of drive pawls 21 protrude within a plurality of reel grooves 23 formed on the inner periphery of the center hole 9. At that time, the plurality of drive claws 21
has a tapered part 22 that tapers in the outer circumferential direction on a plane perpendicular to the central axis part 3, and the width 11 at the tip of the tapered part 22 of the plurality of drive claws 21 and the width 11 at the root of the tapered part 22 The relationship between the width I2 and the width of the plurality of reel grooves 23 is 11
< L < 12.

Therefore, the plurality of driving pawls 21 urged by the spring 5 to protrude in the outer circumferential direction of the central shaft portion 3 are
2 protrudes into the plurality of reel grooves 23 while contacting the entrance corners 25 of the plurality of reel grooves 23. At the same time, the first
As shown in the figure, an annular convex portion 12 formed on the lower surface of the tape reel 8 is pressed onto the upper surface of the reel stand main body 2 by the spring force of a leaf spring 15. When the tape reel 8 is attached to the reel stand 1, the tape reel 8 floats a certain amount above the lower half 16 against the leaf spring 15, and becomes rotatable.

When the reel stand 1 is rotated by the motor shaft 6 of a reel motor (not shown), the tape reel 8 is fitted onto the reel stand main body 2 by the plurality of drive claws 21 without any clearance. The reel table 1 is rotated integrally with the reel stand 1 without slipping between the reel stand 1 and the reel stand 1.

On the other hand, the tape reel 8 is attached to the central shaft portion 3 of the reel stand 1.
When the plurality of reel grooves 23 and the plurality of drive pawls 21 are out of phase as shown by the dashed line in FIG. The claw 21 is pushed into the central shaft portion 3 against the spring 5, and in this state, the annular convex portion 12 of the tape reel 8 is brought into close contact with the upper surface of the reel stand main body 2. When the reel stand 1 is rotated by the motor shaft 6, the annular convex portion 12 of the tape reel 8 slides relatively on the reel stand main body 2, and the tapered portion 22 of the plurality of driving pawls 21 is connected to the plurality of reel grooves 23. The reel protrudes into the plurality of reel grooves 23 while in contact with the inlet corner 25 of the reel.

As described above, according to this embodiment, the plurality of drive claws 21 have a shape having a tapered portion 22 that tapers in the outer circumferential direction on a plane perpendicular to the central axis portion 3, and the tapered portion 22 of the plurality of drive claws 21 The plurality of driving claws 21 protrude into the plurality of reel grooves 23 with the plurality of drive claws 21 in contact with the entrance corners 25 of the plurality of reel grooves 23, thereby fitting the tape reel 8 onto the reel stand main body 2 without any clearance. With this structure, in order to increase the friction between the annular convex portion 12 of the tape reel 8 and the upper surface of the reel stand main body 2, a high friction member 17 made of rubber or the like is provided on the outer periphery of the upper surface of the reel stand main body 2. It is possible to prevent slippage between the reel stand 1 and the tape reel 8, and to reliably transmit the torque of the reel motor (not shown) from the reel metalwork to the tape reel 8. , it is possible to perform tension servo with high responsiveness of the running tape by the reel motor, and when the center hole 9 of the tape reel 8 is fitted to the center shaft portion 3 of the reel stand 1, the plurality of driving claws 21 and the plurality of Even if the reel grooves 23 are out of phase and the plurality of drive claws 21 are pushed into the central shaft portion 3, the rotation of the reel stand 1 will cause the annular convex portion 12 of the tape reel 8 to move on the reel stand main body 2. relatively slippery,
The tapered portions 22 of the plurality of drive claws 21 are connected to the plurality of reel grooves 23.
The plurality of drive claws 21 can protrude into the plurality of reel grooves 23 while in contact with the entrance corner 25 of the reel groove 23 .

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

For example, in this embodiment, a plurality of drive pawls that can freely move in and out of the center shaft portion and are biased toward the outer circumference are provided, and a plurality of reel grooves are provided on the inner circumference of the center hole of the tape reel. A plurality of drive pawls are provided on the inner periphery of the center hole of the reel and are biased in the inner circumferential direction, and a plurality of reel grooves are provided on the outer periphery of the central shaft portion. Either one has a shape having a tapered part that tapers in the inner circumferential direction on a plane perpendicular to the central axis part, and a plurality of drive pawls protruding into the plurality of reel grooves come into contact with the plurality of reel grooves in the tapered part. A similar effect can be obtained even if the tape reel is fitted onto the reel stand main body by contacting the tape reel.

Effects of the Invention As described above, the present invention provides a plurality of drive pawls which are provided on the outer periphery of the central shaft portion of the reel stand main body at equal intervals and can move in and out with a fixed stroke in the radial direction, and which are biased in the outer circumferential direction. At least one of B- and the plurality of reel grooves provided at equal intervals on the inner circumference of the center hole of the tape reel is shaped to have a tapered portion that tapers in the outer circumferential direction on a plane perpendicular to the center axis, By configuring the tape reel to fit onto the reel stand main body by a plurality of drive claws protruding into the plurality of reel grooves coming into contact with the plurality of reel grooves at the tapered part, the reel stand and the tape reel can be connected to each other. The tape reel can be rotated integrally with the reel stand by multiple drive pawls without slipping between them, and the torque of the reel motor can be reliably transmitted from the reel stand to the tape reel. The tension servo with high responsiveness of the running tape can be placed on the tail side, and when the center hole of the tape reel is fitted to the center shaft of the reel stand, the phases of the plurality of reel grooves and the plurality of drive pawls can be adjusted. Even if the multiple drive claws are pushed into the center shaft due to misalignment, the tape reel slides relatively on the reel base body due to the rotation of the reel base, and the multiple drive claws protrude into the multiple reel grooves. The practical effects are great.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing how a tape reel is attached to a reel stand in an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of the same, and FIG.
The figure is a cross-sectional view showing how the tape reel is mounted on the reel stand of the first conventional example, FIG. 4 is a vertical cross-sectional view of the same, and FIG. It is a longitudinal cross-sectional view showing attachment. 1... Reel stand, 2... Reel stand body, 3
... Central shaft portion, 8... Tape reel, 9.
...Center hole, 21...Plural drive claws, 22...
Tapered portion, 23... multiple reel grooves. Name of agent Patent attorney Shigetaka Awano and 1 other person Takaku = Hiku 1 Shi Son-in-law 4040 Famous =) Bi Rental Fuchi double→-
! a'r''
-CXJ (') coo-Q, a K cluster e i e- one 1 tokii] 畢8fu akihaya, ii'piG': eef 912 taku) lead ninguchi ox II - ox 111 to 4! ! <Ip →= =1 1 Heat 40 Toki: ″ Fukichi?! e'pbo GG ′! Taku 12 Tsugane) Ushicho!! +h -f+ Whip beast-+c+) Sunco c> 9mi

Claims (1)

[Claims] a reel stand main body that comes into contact with the lower surface of the tape reel; and a central shaft part that is provided perpendicularly to the center of the reel stand main body and into which the center hole of the tape reel is inserted and serves as a center of rotation of the reel stand main body and the tape reel. , a plurality of reels having a plurality of driving pawls provided on the central shaft portion so as to be movable in the radial direction and biased in the outer circumferential direction, and the plurality of driving pawls are provided on the inner periphery of the center hole. A reel stand configured to rotate the tape reel by protruding into a groove, wherein at least one of the plurality of drive claws and the plurality of reel grooves is on a plane perpendicular to the central axis. The plurality of drive claws protruding into the plurality of reel grooves abut against the plurality of reel grooves in the tapered portion, thereby moving the tape reel into the reel stand main body. A reel stand configured to be fitted onto the reel stand.