JPH11317045A - Magnetic tape cassette and assembling method of magnetic tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic tape cassette and the assembling method of the magnetic tape cassette attaining the improvement of efficiency of the assembling work by preventing a reel spring from floating when the reel spring for pressurizing the tape reel is fixed to a cassette half. SOLUTION: In the magnetic tape cassette 1, a groove part 4 is formed on the upper half cassette 2 and a notch 3d is formed on a base end part 3b of the leaf spring 3 to impart the elasticity in the horizontal width direction. When the base end part 3b is fitted into the groove part 4, the base end part 2b in the horizontal width direction is shortened, and after the insertion, it is restrained to the groove part 4 in the outside direction of the base end part 3b by the elasticity to prevent the reel spring 3 from floating. Consequently, the fixing work of the reel spring 3 is efficiently and accurately performed, then the assembling work of the magnetic tape cassette is efficiently carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cassette provided with a leaf urging leaf spring for elastically pressing a tape reel rotatably housed in upper and lower cassette halves, and the reel urging plate. The present invention relates to a method of assembling a spring for biasing a reel applied when assembling a spring to a cassette half.

[0002]

2. Description of the Related Art Conventionally, in audio equipment and video equipment, a pair of tape reels is rotatably held in upper and lower cassette halves, and recording and reproduction are performed by running a magnetic tape wound around the tape reels. Magnetic tape cassettes such as digital video cassettes (DVC) are widely used.

The tape reel is pressed toward the lower cassette half by a band-shaped reel urging leaf spring (hereinafter, simply referred to as a reel spring) attached to the inner surface of the upper cassette half in a cantilever manner. It is configured as follows. Further, the reel spring is provided corresponding to each of the pair of tape reels.

Hereinafter, the reel spring will be described in more detail with reference to FIGS. FIG. 15 is a plan view showing the shape of the inner surface of the upper cassette half 52 constituting the large (L) size DVC cassette 51. The upper cassette half 52 is provided with a pair of reel springs 53 for pressing a pair of tape reels (both not shown) rotatably attached to the lower cassette half toward the upper cassette half. The reel spring 53 is made of a band-shaped metal plate as shown in FIGS. 16 and 17, and has an arm portion 53a for elastically pressing the tape reel and a base end portion fixed to the inner surface of the upper cassette half 52. 53b, and a through-hole 53c is formed in the base end 53b.

Next, a method of fixing the reel spring 53 to the upper cassette half 52 will be described. As shown in FIG.
Through the boss portion 54 provided at the bottom. Next, a pair of positioning ribs 5 provided on the upper cassette half 52 is provided.
The base end portion 53b is fitted between the five and the positioning of the reel spring 53 in the width direction is performed. While maintaining this state, the boss 54
Is melted by ultrasonic vibration, and the arm portion 53a is fixed to the inside of the cassette so that the arm portion 53a projects downward, and finally the state shown in FIG. 15 is obtained.

[0006]

When the reel spring 53 is fixed to the upper cassette half 52, it is necessary to penetrate the boss portion 54 through the through hole 53c. Therefore, the through hole 5
The diameter of 3c is set to be slightly larger than the diameter of the boss portion 54 so that penetration can be easily performed. On the other hand, the center of gravity of the leaf spring 53 is on the right side of the arm 53a from the bent position. Therefore, the top of the boss 54 is melted by ultrasonic waves, and the reel spring 53 is moved to the upper cassette half 52.
17, the rear end of the base end portion 53b formed on the reel spring 53 sometimes floats as shown by the interval t as shown in FIG. Thus, the proximal end 53
If b rises, it is necessary to press the base end portion 53b against the upper cassette half 52 again and then fix it to the boss portion 54, which is very troublesome.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above problems, and a magnetic tape cassette and a magnetic tape cassette which are configured to easily fix a reel spring that elastically presses a tape reel. An object of the present invention is to provide an assembling method.

[0008]

According to the present invention, a pair of tape reels around which a magnetic tape is wound are rotatably supported in a cassette case comprising upper and lower cassette halves, and are formed at a base end portion. A reel which is cantilevered by the upper cassette half by welding the boss portion in a state where the through-hole is fitted into the boss portion of the upper cassette half, and biases each of the tape reels to predetermined sides. In a magnetic tape cassette provided with a biasing leaf spring, a groove is formed at a predetermined position of the upper cassette half for fixing the base end of the reel biasing leaf spring, and the groove is formed in a width direction of the base end. A notch is formed along the longitudinal direction of the base end to impart elasticity, and the base end is held in the groove by the elasticity. It is solved me.

According to the magnetic tape cassette having the above configuration,
A notch is formed in the base end of the reel spring to impart elasticity in the width direction of the base end, and the elasticity locks the groove, so that when the reel spring is fixed to the boss, the reel spring can be prevented from falling down. it can. Accordingly, the work of assembling the reel spring to the upper cassette half can be efficiently performed.

Another object of the present invention is to provide a reel urging device for rotatably supporting a pair of tape reels around which a magnetic tape is wound in a cassette case comprising upper and lower cassette halves, and for urging the tape reel. A method of assembling a magnetic tape cassette in which a base end of a leaf spring is fixed to a predetermined position of the upper cassette half, wherein the base of the flat plate spring for urging the reel is provided at a predetermined position of the upper cassette half. An end portion is fixed, and the vicinity of the fixing position is pressed against the upper cassette half side by a pressing jig, and a bending jig is inserted from a gap between a free end of the reel biasing leaf spring and the upper cassette half. And bending the holding jig to a predetermined angle from the holding position of the holding jig. That.

According to the method of assembling the magnetic tape cassette having the above-described configuration, the base end of the reel spring having an initial shape of a flat plate is fixed to the boss portion, and then the vicinity of the fixing position is pressed by the pressing jig. Then, the reel spring is bent at a predetermined angle by a bending jig. Therefore, when the reel spring is fixed, the reel spring has a flat plate shape, so that the reel spring does not rise from the cassette half, and the assembling operation can be performed efficiently and reliably.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a magnetic tape cassette according to the present invention will be described in detail with reference to FIGS. 1 is a plan view of the upper cassette half of the magnetic tape cassette of the present embodiment, FIG. 2 is an enlarged perspective view showing a groove portion for fitting the reel spring in FIG. 1, and FIG. 3 is a perspective view of the reel spring in FIG. 4 is a partially enlarged plan view of a main part for explaining the elastic action of the reel spring in FIG. 3, and FIG. 5 is a perspective view showing a locked state of the reel spring in FIG.

As shown in FIG. 1, a magnetic tape cassette 1
Has a configuration in which an upper cassette half 2 and a lower cassette half (not shown) are overlapped, and a pair of tape reels (not shown) are rotatably mounted on the lower cassette half. The upper cassette half 2 has a pair of reel springs 3 for pressing the tape reel toward the lower cassette half.
Is provided. As shown in FIG. 2, a concave groove portion 4 is formed at a position where the reel spring 3 is fixed, and a boss portion 5 is formed inside the groove portion 4 in a standing state. The groove 4 is
Two of the upper cassette halves 2 are formed, one of which is shown.

Further, as shown in FIG. 3, the reel spring 3
An arm portion 3a, which is formed of a band-shaped metal plate and elastically presses the tape reel, and a base end portion 3b which is fixed after fitting into the groove portion 4 are formed, and a through hole 3c is formed in the base end portion 3b. Are formed. A wedge-shaped cut 3d is formed at the rear end side of the base end 3b up to the vicinity of the through hole 3c. The base end 3b has the following dimensional settings to be fitted into the groove 4. That is, FIG.
The width W2 of the rear end of the base end 3b is set to be larger (W2> W1) than the width W1 of the groove 4, as shown in FIG.
2 can be reduced as indicated by the imaginary line in the figure, and after the reduction, it attempts to elastically return to its original shape. In addition,
The length L1 in the longitudinal direction of the groove 4 is slightly longer than the length L2 in the longitudinal direction of the base end 3b, and the bottom has a gentle slope.

When the reel spring 3 is fixed to the upper cassette half 2 as shown in FIG. 5, the boss 5 is inserted into the through hole 3c, and then the rear end of the base end 3b is reduced to W1 or less to form the groove. 4, the base end 3 b is released from the contraction, and is elastically locked in the groove 4. In the present embodiment as well, the arm 3a is longer than the length of the base end 3b, and the center of gravity is on the arm 3a side.
However, since the base end 3b is locked in the groove 4, after the base end 3b is fitted into the groove 4, no inconvenience such as falling down to the side of the arm 3a occurs at all. 5 can stably perform the welding step using ultrasonic waves. Therefore, the reel spring 3 can be securely fixed in the groove 4 without displacement.

As described above, in the present embodiment, the base end portion 3b of the reel spring 3 is provided with elasticity and is locked in the groove 4 by this elasticity, so that the reel spring 3 can be reliably prevented from falling down. it can. Therefore, the efficiency of the operation of assembling the magnetic tape cassette including the operation of fixing the reel spring 3 to the upper cassette half 2 can be improved.

Next, a second embodiment of the magnetic tape cassette according to the present invention will be described in detail with reference to FIGS. FIG. 6 is a perspective view of the reel spring of the present embodiment, FIG. 7 is a partially enlarged plan view of a main part illustrating the elastic action of the reel spring in FIG. 6, and FIG. 8 is a perspective view showing a locked state of the reel spring. . The difference between the present embodiment and the first embodiment is as follows.
The notch 6d of the reel spring 6 is formed so as to communicate with the through hole 6c. As shown in FIG. 7, in the reel spring 6 of the present embodiment, the width W2 of the base end portion 6b is set to be larger than the width W1 of the groove portion 4 (W2> W1). In this configuration, the portion 6b is fitted in the groove 4 in a reduced state. At this time, since the cut 6d is formed deeply so as to communicate with the through hole 6c, the elasticity of the base end 6b is improved, and the work of reducing the width to the width W1 or less becomes easy. Then, as shown in FIG. 8, when the reel spring 6 is fitted in the groove 4, the reel spring 6 does not fall down, and the welding step of the boss 5 can be performed efficiently.

Next, a method of assembling the magnetic tape cassette according to the present invention will be described in detail with reference to FIGS. 9 is a perspective view showing the shape of the reel spring of the present embodiment, FIG. 10 is a longitudinal sectional view in FIG. 9, FIG. 11 is a partially enlarged perspective view showing the fixing position of the reel spring on the upper cassette half side, and FIGS. FIG. 14 is an operation explanatory view showing the assembling method of the present embodiment. As shown in FIG. 9, the reel spring 11 of the present embodiment is formed in a flat plate shape. However, a through-hole 11a is formed at a position acting as a base end when fixed to the upper cassette half 2, and a bent portion 11b is formed at an end opposite to the through-hole 11a. Therefore, FIG.
When the reel spring 11 is placed on the upper cassette half 2 as shown in FIG. 0, a gap T for inserting a bending jig described later is formed at the end thereof.

As shown in FIG. 11, the upper cassette half 2 has a pair of ribs 12 for positioning the reel spring 11, and a boss 13 in the middle. The configurations of the ribs 12 and the bosses 13 may be the same as those in the related art, and the conventional upper cassette half can be used. Next, as shown in FIG. 12, when the reel spring 11 is fixed to the upper cassette half 2, the boss 13 is inserted into the through hole 11a, and the base end is fitted between the ribs 12, 12. At this stage, the flat plate-shaped reel spring 11 does not cause a floating phenomenon, the displacement of the reel spring 11 is prevented, and when the boss portion 13 is welded by ultrasonic waves,
Since it is a flat plate, it is not necessary to press the reel spring 11, and the fixing work of the reel spring 11 can be easily performed.

Next, as shown in FIG.
Is fixed to the upper cassette half 2 by the pressing jig 14 in the vicinity of the fixing position. That is, the holding jig 14 is lowered from the position shown by the imaginary line to hold the reel spring 11. Next, the bending jig 15 is inserted into the gap T from the horizontal direction, and is rotated while moving in the direction of the holding jig 14, so that the reel spring 11 can be bent to a substantially right angle state as indicated by an imaginary line. . Next, as shown in FIG. 14, the reel spring 11 is urged by a jig (not shown) in the direction of the arrow to form an arm portion having a predetermined elasticity capable of elastically pressing the tape reel. Can be.

As described above, in the method of assembling the magnetic tape cassette according to the present embodiment, the base end of the plate-shaped reel spring 11 is fixed to a predetermined position of the upper cassette half 2 and a jig for holding the vicinity of the fixed position is provided. 14 presses against the upper cassette half 2 side. Then, the bending jig 15 is inserted from the gap T between the free end of the reel spring 11 and the upper cassette half 2 and bent at a predetermined angle from the pressing position of the pressing jig 14. Therefore, the initial shape of the reel spring 1 is flat.
The base end of the reel spring is fixed to the cassette half together with the welding of the boss portion 13, and then the reel spring is bent at a predetermined angle by the bending jig while the vicinity of the fixing position is pressed by the pressing jig. Therefore, at the time when the reel spring is fixed, the reel spring has a flat plate shape, so that the reel spring does not rise from the cassette half, and the assembling work can be performed efficiently and reliably.

[0022]

As described above, in the magnetic tape cassette according to the present invention, a groove is formed at a predetermined position of the upper cassette half for fixing the base end of the biasing leaf spring, and the width of the base end is formed. A cut is formed along the longitudinal direction of the base end to provide elasticity in the direction, and the base end is held in the groove by elasticity. Therefore, when the reel spring is fixed to the boss portion, the fall of the reel spring can be prevented, and the work of assembling the reel spring to the upper cassette half can be performed efficiently.

Further, according to the magnetic tape cassette assembling method of the present invention, the base end of the plate-like biasing leaf spring is fixed to a predetermined position of the upper cassette half, and the vicinity of the fixing position is fixed. Hold down the upper cassette half with the holding jig and insert a bending jig through the gap between the free end of the leaf spring for biasing the reel and the upper cassette half to bend the holder at a predetermined angle from the holding position of the holding jig. I do. Therefore, when the reel spring is fixed, the reel spring has a flat plate shape, so that the reel spring does not rise from the cassette half, and the assembling operation can be performed efficiently and reliably.

[Brief description of the drawings]

FIG. 1 is a plan view of an upper cassette half showing a first embodiment of a magnetic tape cassette according to the present invention.

FIG. 2 is an enlarged perspective view showing the shape of a groove in FIG.

FIG. 3 is a perspective view showing a reel spring in FIG. 1;

FIG. 4 is an enlarged partial plan view of a main part showing a groove portion and an elastic action of a reel spring in FIG. 3;

FIG. 5 is a perspective view showing a locked state of a reel spring in a groove according to the present invention.

FIG. 6 is a perspective view of a reel spring showing a second embodiment of the magnetic tape cassette according to the present invention.

FIG. 7 is an enlarged partial plan view of a main part showing a groove portion and an elastic action of a reel spring in FIG. 6;

FIG. 8 is a perspective view showing a state in which a reel spring is locked in a groove according to the present invention.

FIG. 9 is a perspective view of a reel spring showing one embodiment of a method of assembling a magnetic tape cassette according to the present invention.

FIG. 10 is a longitudinal sectional view showing a shape of a reel spring in FIG. 9;

FIG. 11 is a perspective view showing a shape of a fixing position of a reel spring according to the present invention.

FIG. 12 is a perspective view showing a step of fixing a reel spring according to the present invention.

13 is a longitudinal sectional view showing a state in which the reel spring in FIG. 12 is being bent.

FIG. 14 is a longitudinal sectional view showing a state where bending of the reel spring in FIG. 13 is completed.

FIG. 15 is a plan view showing an example of a conventional upper cassette half.

FIG. 16 is a perspective view showing a conventional reel spring fixing process.

FIG. 17 is a perspective view showing a floating state of a conventional reel spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic tape cassette 2 Upper cassette half 3, 6, 11 Reel spring 3a, 6a Arm part 3b, 6b Base end part 3c, 6c, 11a Through hole 3d, 6d Cut 4 Groove part 5, 13 Boss part 12 Rib 14 Jig 15 bending jig

Claims (2)

[Claims] 1. A pair of tape reels around which a magnetic tape is wound are rotatably supported in a cassette case composed of upper and lower cassette halves, and a through hole formed in a base end portion is fitted into a boss portion of the upper cassette half. In the magnetic tape cassette provided with a reel biasing leaf spring that is cantilevered by the upper cassette half by welding the boss portion while being inserted, and biases each of the tape reels to a predetermined side. Forming a groove at a predetermined position of the upper cassette half for fixing the base end of the reel urging leaf spring;
A magnetic tape, wherein a cut is formed along a longitudinal direction of the base end to impart elasticity in the width direction of the base end, and the base end is held in the groove by the elasticity. cassette. 2. A pair of tape reels each having a magnetic tape wound thereon are rotatably supported in a cassette case composed of upper and lower cassette halves, and a base end of a reel urging leaf spring for urging the tape reels is provided. In a method of assembling a magnetic tape cassette fixed to a predetermined position of an upper cassette half, the base end portion of the flat plate-like reel urging leaf spring is fixed to a predetermined position of the upper cassette half, and the fixing is performed. The vicinity of the position is pressed against the upper cassette half side by a holding jig, and a bending jig is inserted from a gap between a free end of the reel urging plate spring and the upper cassette half to hold the holding jig. A method of assembling a magnetic tape cassette, wherein the magnetic tape cassette is bent at a predetermined angle from an attachment position.