JPS6327322Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a tape cassette most suitable for application to, for example, a tape cassette for a video tape recorder.

BACKGROUND ART AND PROBLEMS FIGS. 1 and 2 show a conventional tape cassette for a video tape recorder, in which a cassette housing 1 has an upper half 2 integrally molded from synthetic resin. It consists of the lower half 3,
The upper half 2 and the lower half 3 are fitted from above and below,
For example, set screws 4a to 5 points at the four corners and approximately in the center.
4e, they are screwed together. Inside the cassette case 1 are a pair of left and right reels 5,
6 are rotatably housed, and a magnetic tape 7 is wound and housed around both reels 5 and 6, respectively. A rotatable front cover 9 is attached to the front opening 8 of the cassette housing 1, and the magnetic tape 7 is guided by a pair of tape guides 10 and 11 to the front opening 8 along the inside of the front cover 9. 8 has been passed.

A leaf spring 13 is housed in the space between the lower surface of the upper half 2 and the upper surfaces of both reels 5 and 6 within the cassette housing 1. This leaf spring 13 has a planar shape bent into a substantially V-shape, and is fixed to the upper half 2 at a bending point, which is a substantially central portion 13a in the longitudinal direction, as will be described later. Both ends 13b and 13c in the longitudinal direction of this leaf spring 13
is elastically pressed onto small protrusions 5a, 6a integrally formed on the center portions of the upper surfaces of both reels 5, 6, thereby pressing both reels 5, 6 toward the lower half 3 side. The leaf spring 13 is made of a metal spring such as a stainless steel plate or a phosphor bronze plate, and its central portion 13a is inserted through a small hole 15 into a dowel 14 integrally formed on the inner surface (lower surface) of the upper half 2. and is fixed by welding the lower end of the dowel 14. Also, the central portion 13a of the leaf spring 13
A position near the dowel 14 is inserted through an insertion hole 17 into a screw fixing boss 16 of a set screw 4e integrally formed on the inner surface of the upper half 2.

On the other hand, a light emitting element insertion hole 19 is provided in the lower half 3 at a position corresponding to the intermediate portion of both reels 5 and 6.
Upper and lower halves having a substantially U-shaped cross section are integrally molded on the inner surfaces (upper and lower surfaces) of the upper half 2 and the lower half 3, respectively, to surround the light emitting element insertion hole 19 inside the cassette housing 1. A pair of cylindrical walls 20, 21
is provided. Note that both these cylindrical walls 20, 2
Reference numeral 1 denotes a pair of upper and lower partition walls 22 and 23 that are integrally molded on the inner surfaces of the upper half 2 and the lower half 3, respectively, to partition the inside of the cassette housing 1 between the reel storage section side and the front opening 8 side. It is located on the back of the .
A pair of left and right window holes 24 are provided at the upper and lower abutting portions (approximately at the center in the vertical direction) of the left and right sides of both the cylindrical walls 20 and 21. Further, a pair of left and right light detection windows 25 are provided on both left and right side walls 1a of the cassette housing 1, facing the window holes 24. Note that when the front cover 9 is in the closed state, both the light detection windows 25 are closed by the left and right ends 9a of the front cover 9, but when the tape cassette is attached to the video tape recorder and the front cover 9 is opened. When the lid is closed, both of these light detection windows 25 are opened.

This tape cassette is constructed as described above, and when it is installed in a video tape recorder,
As shown by the imaginary line in FIG. 2, the light emitting element insertion hole 19
A light emitting element 26 such as a small lamp is inserted inside.
At the same time, as shown in FIG. 1, light-receiving elements 27 and 28 such as phototransistors are arranged on the outside of both light-detecting windows 25 opened by opening the front cover 9. When the magnetic tape 7 is recorded or played back by a video tape recorder, when the end of the tape is reached, a transparent leader tape is placed on one of the pair of optical paths between the window holes 24 and the light detection windows 25. appears, the light emitted from the light emitting element 26 to both sides of the window holes 24 passes through the transparent leader tape and hits either of the light detection windows 2.
5 is received by one of the light receiving elements 27, and optical detection of the tape end is performed. Note that when the tape end is optically detected, the running of the magnetic tape 7 is automatically stopped.

However, in the conventional tape cassette constructed as described above, there is a problem when assembling the cassette housing 1 by fitting the upper and lower halves 2 and 3 from above and securing them with the five set screws 4a to 4e. Ta.

In other words, if the leaf springs 13 were not provided, when the upper and lower halves 2 and 3 were fitted from above and below, they would fit together easily, but because of the leaf springs 13, the two halves would fit together easily as shown in FIG. Due to the repulsive force of the leaf spring 13, the upper half 2 floats significantly relative to the lower half 3. Therefore, when screwing, the operator must press the upper half 2 onto the lower half 3 against the leaf spring 13 each time, making the screwing work extremely inconvenient. In addition, on the manufacturing line, while the upper half 2 is fitted onto the lower half 3 and transported to the screw-fastening process position, the upper half 2 may rattle on the lower half 3, causing misalignment. Inconveniences such as the upper half 2 accidentally falling off from the lower half 3 often occur.

Purpose of the invention The present invention aims to provide a tape cassette capable of correcting the above-mentioned defects.

Summary of the invention The present invention provides the tape cassette described in FIGS. 1 and 2 with the cylindrical wall integrally molded into one of the upper half or the lower half, and the cylindrical wall. A pair of split grooves are provided on both left and right sides, a pair of fitting walls press-fitted into the split grooves are integrally molded on the other half of the upper half or the lower half, and the upper half and the lower half are provided with a pair of fitting walls press-fitted into the split grooves. When these are fitted from above and below, the above-mentioned fitting walls are press-fitted into the above-mentioned split grooves at a predetermined height, and the combination of these fitting walls and the split grooves forms the above-mentioned window holes. The upper half and the lower half can be temporarily fixed by the frictional force of the fitting between the fitting walls and the dividing grooves, which greatly facilitates the assembly work of the cassette case. We can provide something that works well.

Embodiment An embodiment in which the present invention is applied to a tape cassette for a video tape recorder will be described below with reference to FIGS. 3 to 6. Note that structural parts that are the same as those of the conventional example shown in FIGS. 1 and 2 are given the same reference numerals, and their explanations are omitted.

That is, in this tape cassette, first, as shown in FIG.
are integrally molded. This cylindrical wall 31 is molded so as to be integrally connected to the back side of the partition wall 23 and extends above the partition wall 23. As will be described later, when the upper and lower halves 2 and 3 are fitted from above and below, the upper end surface 3 of the cylindrical wall 31
The height h 1 of the cylindrical wall 31 is such that the leaf spring 1a can be fixed by pressing the center part of the leaf spring 13 fixed to the inner surface (lower surface) of the upper half ₂ from below.
is constructed high enough. However, a pair of grooves 32 are vertically formed on both left and right sides of the cylindrical wall 31 of the lever. This double groove 32 is connected to the cylindrical wall 31.
It is vertically cut downward from the upper end surface 31a, and the height _h2 is set to be, for example, approximately 2/3 or more of the height _h1 of the cylindrical wall 31. Of the front and rear inner surfaces 32a of the split groove 32, for example, a tapered surface 33 that widens upward is formed at the upper end of the front inner surface 32a.

On the other hand, on the inner surface (lower surface) of the upper half 2, a pair of fitting walls 34 which are press-fitted into the above-mentioned split grooves 32 are integrally molded. Both fitting walls 34 are integrally connected to the back surface of the partition wall 22 via a pair of connecting walls 35 and are formed in a parallel shape, and the height h ₃ of both fitting walls 34 is The height is, for example, 1/2 of the height _h2 of the groove 32. Further, the width w ₁ of both fitting walls 34 in the front-rear direction is configured to be slightly larger than the groove width w ₂ of both dividing grooves 32 in the front-rear direction.

The tape cassette of the present invention is constructed as described above, and when the upper and lower halves 2 and 3 are fitted from above and below when assembling the cassette housing 1 as shown in FIGS. Both ends 13b and 13c of the leaf spring 13 are pressed against the elasticity onto the small protrusions 5a and 6a at the center of the upper surfaces of the reels 5 and 6. ] As shown in FIG. 6, both connecting walls 35 of the upper half 2 are fitted to the outer sides of both left and right sides of the cylindrical wall 31, and at the same time both fitting walls 34 are inserted into the dividing grooves 32 so that the cylindrical wall 31 They are press-fitted against the elasticity in the front-rear direction. Note that the elasticity of the cylindrical wall 31 in the front-rear direction at this time is obtained by forming both dividing grooves 32, and since both tapered surfaces 33 are formed,
Both fitting walls 34 can be easily press-fitted into the split grooves 32.

By press-fitting both the fitting walls 34 into the split grooves 32, the window holes 24 are formed by the combination of the fitting walls 34 and the split grooves 32. At the same time, the front and rear outer surfaces 34a of both fitting walls 34 and the front and rear inner surfaces 32 of both dividing grooves 32
The upper and lower halves 2 and 3 are in a temporarily fixed state in which they are mechanically coupled due to the frictional force of fitting with a. This temporary fixing prevents the upper half 2 from accidentally floating above the lower half 3 due to the repulsive force of the leaf spring 13. Therefore, when screwing the upper and lower halves 2 and 3 using the five set screws 4a to 4e, the operator must press the upper half 2 onto the lower half 3 against the leaf spring 13 while tightening the screws. This eliminates the need for screws, and the work of screwing them becomes significantly easier. In addition, on the manufacturing line, even when the upper half 2 is fitted onto the lower half 3 and transported to the screw-fastening process position, the upper half 2 may wobble on the lower half 3, causing misalignment. Inconveniences such as the upper half 2 accidentally falling off from the lower half 3 can also be reliably prevented.

Note that when the upper and lower halves 2 and 3 are screwed together to assemble the cassette housing 1, the upper end surface 31a of the cylindrical wall 31 is aligned with the center portion 13 of the leaf spring 13, as shown in FIG.
Press a from below to remove the inner surface (lower surface) of upper half 2.
Because the leaf spring 13 gets caught between
The central portion 13a of is firmly fixed to the upper half 2.

Although one embodiment of the present invention has been described above, according to the present invention, contrary to the configuration shown in the embodiment, the cylindrical wall 3
1 may be integrally molded on the upper half 2 side, and both fitting walls 34 may be integrally molded on the lower half 3 side.

Application Examples The present invention is not limited to tape cassettes for video tape recorders, but can be applied to tape cassettes for various other recording/reproducing devices and information processing devices.

Effects of the invention The present invention, when the upper and lower halves are fitted from above and below as described above, press-fits both the fitting walls and the split grooves to form a pair of window holes on both the left and right sides of the cylindrical wall. At the same time, the upper and lower halves are configured to be temporarily attached mechanically, and the upper and lower halves are configured to be temporarily attached using the structure for forming the pair of window holes. be. Since the upper and lower halves can be mechanically temporarily fastened, it is extremely easy to fasten them with a single screw when assembling the cassette case by fastening them with a plurality of set screws. In addition, since the upper and lower halves can be screwed together while being mechanically temporarily secured, automatic assembly using an automatic machine can be performed very easily.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing a conventional example of a tape cassette for a video tape recorder, and FIG. 2 is a sectional view taken along the line shown in FIG. 1. 3 to 6 show an embodiment of a tape cassette for a video tape recorder to which the present invention is applied. FIG. 3 is an exploded perspective view of the main parts, and FIG. FIG. 5 is a cross-sectional view taken from the line shown in FIG. 4, and FIG. 6 is a perspective view showing the press-fitted state of the main parts. In addition, in the symbols used in the drawings, 1...Cassette housing, 2...Upper half, 3...Lower half,
4a, 4b, 4c, 4d, 4e...stop screws, 5,
6... Reel, 7... Magnetic tape, 8... Front opening, 13... Leaf spring, 13a... Center portion of leaf spring, 13b, 13c... Both ends of leaf spring, 19...
...Light emitting element insertion hole, 24... Window hole, 25... Light detection window, 26... Light emitting element, 27... Light receiving element, 3
1... Cylindrical wall, 32... Division groove, 33... Tapered surface, 34... Fitting wall, 35... Connection wall.

Claims (1)

[Scope of utility model registration request] A cassette housing composed of an upper half and a lower half, a pair of reels rotatably housed in the cassette housing, a tape wound around and housed on both reels, and a cassette housing consisting of an upper half and a lower half; a leaf spring having a central portion fixed to the inner surface of the upper half and elastically pressing the central portions of the reels toward the lower half at both ends in the longitudinal direction; and an intermediate portion of the reels. A light emitting element insertion hole opened in the lower half at a corresponding position, a cylindrical wall integrally molded within the cassette housing to surround the light emitting element insertion hole, and a cylindrical wall provided on the left and right sides of the cylindrical wall. It has a pair of left and right window holes provided at substantially the center in the vertical direction on both sides, and a pair of left and right light detection windows provided on both left and right sides of the cassette casing, facing the both window holes. In the tape cassette, the cylindrical wall is integrally molded into one of the upper half or the lower half, and a pair of split grooves are provided on both left and right sides of the cylindrical wall, and the cylindrical wall is press-fitted into the split groove. A pair of fitting walls to be fitted are provided by integral molding on the other half of the upper half or the lower half, and when the upper half and the lower half are fitted from above and below, both the fitting walls are connected to the By press-fitting into the split grooves at a predetermined height, the above-mentioned window holes are formed by the combination of these fitting walls and the split grooves, and the fitting friction between these fitting walls and the split grooves is reduced. A tape cassette characterized in that the upper half and the lower half are temporarily fixed together by force.