JPH11149747A - Tape reel forming method and tape reel - Google Patents

Abstract

(57) An object of the present invention is to provide a tape reel forming method and a tape reel forming method capable of preventing deformation of a lower edge side of a tape even if the reel hub is deformed due to tight tightening of a tape wound around a reel hub of the tape reel. The temperature of a mold forming the inside of an outer peripheral side hub corresponding to a base portion formed by connecting a reel hub and a flange portion is integrally formed in a state where the temperature is higher than the temperature of a mold forming the outside. Using the sink phenomenon caused by the difference, a gentle concave portion is formed outside the base portion. Alternatively, the inside of the outer peripheral hub of the root portion connected to the reel hub and the flange portion is formed thick, and a concave portion is formed outside the root portion by utilizing the sink phenomenon of the thick portion. Further, the tape reel has a structure in which a gentle concave portion is provided outside a root portion formed by connecting the reel hub and the flange portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a tape reel and a tape reel, and more particularly, to a method for extending a portion for recording and reproducing a control signal with respect to an extension of a tape caused by tight winding of the tape. The present invention relates to a method of forming a tape reel and a tape reel that minimizes the occurrence of a tape reel.

[0002]

2. Description of the Related Art Conventionally, a tape cassette containing a magnetic tape, which is a tape body serving as a recording medium for information signals, has a pair of tape reels rotatable in a cassette half formed by butt-connecting a pair of upper and lower halves. A structure is known in which a magnetic tape is wound between these tape reels.

A tape reel which is housed in a tape cassette and around which a magnetic tape is wound is formed by molding a synthetic resin material, and as shown in FIGS. 7 and 8, a cylindrical shape around which a magnetic tape 30 is wound. And a disc-shaped flange portion 20 integrally formed on the base side of the reel hub 10.

[0004] The reel hub 10 concentrically forms an outer peripheral hub 11 for directly winding a magnetic tape and an inner peripheral hub 12 to which a reel drive shaft disposed on the magnetic recording and / or reproducing apparatus side is fitted. It has a structure provided.

[0005] Between the outer peripheral hub 11 and the inner peripheral hub 12,
It has a structure connected by a plurality of radially continuous ribs 13. The plurality of ribs 13 are connected to the outer hub 1.
This is for preventing deformation such as falling of the inner hub 1 and the inner peripheral side hub 12.

The flange portion 20 is formed in a disk shape so as to protrude from the outer periphery at one end side of the base portion of the outer peripheral side hub 11,
The side edges of the magnetic tape 30 wound around the outer peripheral side hub 11 are guided and supported, so that the winding appearance is adjusted.

[0007] A circumferential portion of the outer peripheral side hub 11 projecting downward is mounted on a reel base provided on the magnetic recording and / or reproducing apparatus side, and a mounting position of the tape reel with respect to the reel base is determined. It is a positioning part 14 for positioning.

The magnetic tape 30 fixes the leader tape connected to the tape end to a part of the outer peripheral hub 11,
It is structured to be wound around the outer peripheral surface of the outer peripheral side hub 11.

The magnetic tape 30, which is a tape wound on a tape reel, is formed by using a thin film made of a synthetic resin as a base material and attaching a magnetic recording medium to one surface of the film sheet. And expands and contracts due to temperature changes. Therefore, when the magnetic tape 30 wound on the tape reel receives a temperature change, the winding state is reduced at the winding portion on the tape reel, that is, so-called tight tightening is caused.

When such tightness of the magnetic tape 30 occurs, as shown in FIGS. 9 and 10, the free end of the outer peripheral hub 11 around which the magnetic tape 30 is wound is deformed so as to reduce its diameter. Let me do it. On the other hand, since the base side where the flange portion 20 is formed is reinforced by the flange portion 20, no large deformation occurs.

[0011]

However, when the magnetic tape 30 is tightly wound as described above, the portion of the magnetic tape 30 that is wound around the free end of the hub 11 on the outer peripheral side is located on the outer peripheral side. The hub 11 contracts by the amount of deformation.

That is, when the tight state of the magnetic tape 30 occurs, as shown in FIG. 10, the portion wound around the base side of the outer peripheral side hub 11 which is reinforced by the flange portion 20 and does not cause deformation is formed on the outer peripheral side. The hub 11 is in an extended state as compared with a portion wound around the free end portion. If it does so, the lower edge 31 side wound around the base side of the outer peripheral side hub 11 of the magnetic tape 30 will be in the shape of a seaweed stretched in the longitudinal direction.

On the other hand, the lower edge 31 of the magnetic tape 30
On the side, control information for controlling the running of the tape, that is, a control (CTL) signal is recorded. For this reason, the so-called partially elongated wakame-shaped magnetic tape 30 whose lower edge 31 side of the magnetic tape 30 has been extended is mounted on a magnetic recording and / or reproducing apparatus such as a video tape recorder and the like, and is mounted on a tape running path in the apparatus. When the tape is loaded and wound on a tape guide drum provided with a rotating magnetic head, a stable winding state cannot be obtained, and problems such as disturbance of images and sounds occur.

Accordingly, even if the tape body such as a magnetic tape wound on a tape reel is tightly wound due to a temperature change, even if the tape body is partially stretched, at least the lower end portion of the tape body is recorded and reproduced. The control information has a problem that must be solved on a tape reel that can be normally recorded and reproduced.

[0015]

In order to solve the above-mentioned problems, a method of forming a tape reel according to the present invention comprises: a reel hub formed of resin and having at least an outer peripheral side hub around which a tape body is wound; A tape reel having a flange portion integrally formed by being connected to a reel hub, wherein a temperature of a mold forming the inside of the outer peripheral side hub corresponding to a root portion where the reel hub and the flange portion are connected to each other. Is formed integrally at a temperature higher than the temperature of the mold that forms the outside, and a concave portion is formed outside the root portion by utilizing a sink phenomenon caused by the temperature difference.

A method of forming a tape reel is a tape comprising a reel hub formed of resin and having at least an outer peripheral side hub around which a tape body is wound, and a flange portion integrally formed integrally with the reel hub. A reel, wherein the inside of the outer peripheral side hub of a root portion where the reel hub and the flange portion are connected is formed to be thick, and a concave portion is formed outside the root portion using a sink phenomenon of the thick portion. It is to form.

Further, the tape reel is a tape reel having a cylindrical reel hub around which a tape body is wound, and a flange portion integrally formed integrally with the reel hub. This is because a gentle concave portion is provided outside the base portion where the and are continuously provided.

In such a tape reel forming method and the tape reel, the upper end of the outer peripheral side hub is formed by forming a gentle concave portion outside the root portion continuously provided between the reel hub and the flange portion and tightening the tape body. Even if the diameter of the portion is deformed, the extension of the lower edge portion of the tape body can be minimized. Therefore, even if the elongation of the tape body occurs, the control information existing at the lower end of the tape body can be normally reproduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of a tape reel according to the present invention will be described with reference to the drawings. still,
The same components as in the prior art will be described with the same reference numerals.

As shown in FIG. 1, the tape reel for a tape cassette according to the present invention is the same as the conventional one described above, and includes a reel hub 10 around which a magnetic tape 30 as a tape body is wound, And a flange portion 20 integrally formed on the base side of the main body.

The reel hub 10 has an outer peripheral hub 11 on which the magnetic tape 30 is directly wound and an inner peripheral hub 1 on which a reel drive shaft disposed on the magnetic recording and / or reproducing apparatus side is fitted.
2 are provided concentrically. The outer peripheral hub 11 and the inner peripheral hub 12 are connected by a plurality of radially continuous ribs 13.

The flange portion 20 is formed in a disk shape so as to protrude outward from the base side of the outer peripheral side hub 11, that is, from the base portion, and forms a side edge of the magnetic tape 30 wound around the outer peripheral side hub 11. The guides are supported and the winding appearance is adjusted. The portion of the outer peripheral side hub 11 protruding toward the base side is mounted on a reel base provided on the magnetic recording and / or reproducing apparatus side, and serves as a positioning part 14 for determining a mounting position of the tape reel with respect to the reel base. I have.

As shown in FIG. 5, the recording pattern of the magnetic tape 30, which is a tape body, is such that control information 32 is recorded at the lower edge portion of a strip, and video information 33 is recorded on the upper portion.
Is recorded. The control information 32 includes a time code signal 32a and a control (CTL) signal 32b.
And video information 33 is a video (VIDEO) signal 3
3a and an audio (AUDIO) signal 33b. The video and audio signals of the video signal 33a and the audio signal 33b, which are the video information 33, are corrected by the correction function in recent digital video so that the error is not noticed even if the signal has an error. be able to.

However, if there is an error in the control signal 32b, which is the control information 32, the correction cannot be performed. Therefore, the lower edge of the magnetic tape 30 is elongated due to the tightening described in the related art. If it is in the stretched wakame state, an error occurs in the control signal 32b when mounted on a magnetic recording and / or reproducing apparatus, and problems such as disturbed images and sounds occur.

Therefore, the present invention is directed to a case where, as shown in FIG. 1, a tape body such as a magnetic tape 30 wound on a tape reel is subjected to a partial elongation due to a temperature change or the like, that is, a so-called tight winding. The gentle concave portion 4 for minimizing the lower edge of the magnetic tape 30 from being stretched.
0 is provided outside the root portion where the outer peripheral side hub 11 and the flange portion 20 are continuously provided.

As a method of providing the gentle concave portion 40, there is a method of forming the gentle concave portion 40 when forming a tape reel.
Is desirably formed in a gentle convex shape corresponding to the concave portion 40. However, in reality, the convex portion of the mold is undercut, and the formed tape reel cannot be released.

Therefore, in the embodiment according to the present invention, a gentle concave portion is formed by two methods.

The first method for forming a gentle concave portion is as follows.
As shown in FIG. 4, the temperature of the mold 50a that forms the inside of the outer peripheral side hub 11 corresponding to the root portion where the reel hub 10 (see FIG. 1) and the flange portion 20 are connected is set to the mold 50b that forms the outside. Are formed integrally at a temperature higher than the above temperature, and a concave portion 40 (see FIG. 1) is formed outside the base portion by utilizing the sink phenomenon caused by the temperature difference.

Specifically, a temperature controller 51 such as a thermocouple is installed in a mold 50a between the outer peripheral side hub 11 and the inner peripheral side hub 12. Then, the molding temperature of the root portion of the outer peripheral side hub 11 is set higher than that of the other portions, and the cooling shrinkage is delayed to increase the molding shrinkage rate of the other portions, causing sink marks to occur. The gentle recess 40 (FIG. 1)
Reference). Here, the molding shrinkage rate at the portion where the cooling of the resin is slow and at the portion where the cooling is early is in a relationship where the portion where the cooling is slow is larger than the portion where the cooling is fast.

That is, if cooling is performed in a state where the temperature of the inner lower end of the outer peripheral side hub 11 is higher than the temperature of the outer lower end,
Since the inner lower end portion of the outer peripheral side hub 11, which is a high temperature portion, cools down more slowly than the outer lower end portion, the outer periphery of the root portion is uniformly dented inward due to sink marks and hardens. Therefore, a gentle concave portion 40 (see FIG. 1) can be formed at the outer base portion of the outer peripheral side hub 11.

In order to provide this temperature difference, as shown in FIG. 4, two temperature regulators 51 and 51a are installed, and the outer peripheral side corresponding to the root portion where the reel hub 10 and the flange portion 20 are continuously provided. The mold 50a forming the inside of the hub 11 includes one temperature controller 51, and the mold 50a forming the outside.
b is provided with another temperature controller 51a. Then, the temperature of the inner mold 50a is changed to the outer mold 50.
If they are formed integrally at a temperature higher than the temperature of b,
It is possible to form a temperature difference at which a more accurate sink phenomenon easily occurs.

The outer peripheral side hub 11 formed by such a method.
As shown in FIGS. 2 and 3, the tape reel provided with a gentle concave portion 40 at the lower end is a so-called tape reel in which the magnetic tape is subjected to a temperature change and the winding state is reduced at the winding portion on the tape reel. When the tightness of the winding occurs, the free end of the outer peripheral side hub 11 is bent inward and deformed. When deformed, the difference between the diameter of the free end portion and the diameter of the base portion comes out, and the wound magnetic tape elongates in one direction, but the base tape of the outer peripheral side hub 11 around which the magnetic tape is wound is extended. Since the gentle concave portion 40 is formed in the outer peripheral portion, the lower end portion of the wound tape, that is, the control signal 32b
Can be protected from tape expansion.

Next, a second method for forming a gentle concave portion will be described with reference to FIG. Gently concave 4
A second method of forming the thickness 0 is to provide a thick-thickness portion 41 in which the inside of the outer peripheral side hub 11 at the base portion where the reel hub 10 and the flange portion 20 are connected is formed thick. The concave portion 40 is formed outside the base portion by utilizing the sink phenomenon of the portion 41 portion.

More specifically, the cooling of the thick-walled portion 41 provided at the inner base of the outer peripheral side hub 11 is delayed more than other portions, so that the molding shrinkage becomes large and the sink phenomenon occurs outside. That is, the lower end of the outer peripheral side hub 11 is drawn inward, so that a uniform gentle concave portion 40 can be formed around the base portion. In this case, in order to form a gentle concave portion, a structure may be provided in which an inclined portion 42 having a thickness gradually reduced above the thick-wall portion 41 is provided.

[0035]

As described above, the tape reel according to the present invention is provided with a gentle recess at the lower end of a reel hub around which a tape body such as a magnetic tape is wound, so that the cassette can be subjected to a temperature change or the like. , So-called, even in the case of a tight tightening state, minimize the elongation of the lower end of the tape,
By preventing errors in the control signal, magnetic recording and / or
Alternatively, there is an effect that it is possible to maintain a state in which stable tape running is always possible when a cassette is mounted on the reproducing apparatus.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a tape reel having a recess formed by a first method according to the present invention.

FIG. 2 is a cross-sectional view illustrating a state in which the magnetic tape is wound around the magnetic tape in a state where the magnetic tape is wound around the tape reel, and a cross-sectional view illustrating a shape of the magnetic tape.

FIG. 3 is a schematic perspective view showing a state in which the magnetic tape is wound around the tape reel with the magnetic tape wound thereon.

FIG. 4 is a schematic enlarged cross-sectional view of a main part in which a temperature controller for forming the concave portion is provided in a mold.

FIG. 5 is an explanatory diagram showing a recording pattern of a magnetic tape as a tape body.

FIG. 6 is a sectional view showing a tape reel in which a concave portion is formed by the second method according to the present invention.

FIG. 7 is a schematic perspective view showing a tape reel according to the related art.

FIG. 8 is a cross-sectional view of a tape reel according to the related art.

FIG. 9 is a schematic cross-sectional view showing a state in which a magnetic tape is wound around when a magnetic tape is wound around a tape reel in a conventional technique.

FIG. 10 is a schematic perspective view showing a state in which a magnetic tape wound around a tape reel in the related art is partially stretched.

[Explanation of symbols]

10 ... reel hub, 11 ... outer peripheral side hub, 12
..Inner peripheral hub, 13 rib, 14 positioning part, 20 flange part, 30 magnetic tape, 3
2a: time code signal, 32b: control signal, 33: video information, 33a: video signal, 33b: audio signal, 40: recess, 4
DESCRIPTION OF SYMBOLS 1 ... Thick preserving part, 42 ... Inclined part, 50a ... Die, 50b ... Die, 51 ... Temperature controller, 51a
... Temperature controllers

Claims (3)

[Claims] 1. A tape reel comprising: a reel hub formed of a resin and having at least an outer peripheral hub around which a tape body is wound; and a flange portion formed integrally with the reel hub. And the flange portion are integrally formed in a state in which the temperature of the mold forming the inside of the outer peripheral side hub corresponding to the base portion provided continuously with the temperature of the mold forming the outside is higher than the temperature of the mold forming the outside. A method for forming a tape reel, wherein a concave portion is formed outside the base portion using a sink phenomenon. 2. A tape reel comprising: a reel hub formed of a resin and having at least an outer peripheral hub around which a tape body is wound; and a flange portion formed integrally with the reel hub. The inner wall of the outer peripheral side hub of the root portion where the flange and the flange portion are connected is formed to be thick, and a concave portion is formed outside the root portion using the sink phenomenon of the thick portion. A method of forming a tape reel. 3. A tape reel comprising: a cylindrical reel hub on which a tape body is wound; and a flange portion formed integrally with the reel hub, wherein the reel hub and the flange portion are connected to each other. A tape reel characterized by providing a gentle concave portion outside the base portion.