JP2007220290A - Magnetic tape cassette - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic tape cassette which can be decomposed easily, safely, easily preferably without destruction and efficiently in the case of decomposing, separating and sorting an upper half body and a window member which form a substrate of the magnetic tape cassette discarded after use so as to recycle them as raw materials of new products. <P>SOLUTION: The magnetic tape cassette has a resin-made upper half 410 with an opening for forming a transparent window and a transparent resin-made window 412 installed in the opening. At least the upper half and the window are molded in two colors in a single mold using two kinds of resin materials having no compatibility between each other and having no adhesive property to each other. Then, the upper half and the window after molding are fitted to each other from prescribed directions. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cassette having a transparent window that can be disassembled, and in particular, when a magnetic tape cassette is discarded after use, a transparent resin that constitutes a transparent window provided in an upper half of the magnetic tape cassette ( In order to separate the window member made of plastic) from the opening of the base body, that is, the upper half body, and to recycle the base body and the window member as raw materials, that is, in order to be recyclable, the base body (upper half body) ) And the window member can be easily disassembled.

  More specifically, the present invention provides a transparent tape for checking (recognizing) the remaining amount of tape provided in a casing (cassette case) of a magnetic tape cassette constructed by resin molding so that members of different materials can be easily separated. The present invention relates to a magnetic tape cassette formed so that a window can be easily separated from a casing (base body).

More specifically, for example, a magnetic tape cassette in which a long magnetic tape is wound around a pair of winding hubs and the pair of winding hubs are rotatably housed in a casing (cassette case) is well known. It has become. In such a magnetic tape cassette, a transparent window is provided in the upper half of the magnetic tape cassette in order to visually recognize the amount of the magnetic tape wound on the left and right winding hubs. When such a magnetic tape cassette is discarded after use, the upper half of the cassette case and the upper half body (base) and a transparent window are used to save resources and save resources or protect the environment. It is clear that it is most desirable to disassemble each of the parts and recycle them together as new raw materials.
Accordingly, the present invention relates to a magnetic tape cassette (upper half) that can be easily disassembled in consideration of these points.

  In recent years, interest in environmental issues has increased, and there are concerns about adverse environmental impacts due to an increase in various types of waste such as resins (plastics) or composite materials. Therefore, it is becoming important that the amount of waste is small or it does not cause any trouble in environmental conservation even if it is disposed of, so-called environmental load is small. For this reason, it has been promoted to make industrial products advantageous for the circulation system of the entire society by making it easy to disassemble each different material constituting the product and making each part reusable as much as possible.

  By the way, as a large-capacity recording medium for data backup in an external storage device such as a recording / playback tape used for video tape recorders or video cameras for consumer use or business use, or from the upper half and the lower half Magnetic tape of a system in which a cassette case (hereinafter, also simply referred to as a housing) is rotatably accommodated with a pair of winding hubs wound with magnetic tape or a single tape reel wound with magnetic tape. Cassettes are known. For example, magnetic tape cassettes whose structure and dimensions are specified in JIS X6127, X6129, X6130, X6171, X6172 or ECMA-288 are known, and these various magnetic tape cassettes are used for each component. According to the required performance and shape, it is configured as a composite structure in which various metal members and synthetic resin members are combined.

  In these various magnetic tape cassettes, one or two or more provided on the upper plate of the upper half so that the winding amount and winding state of the tape reel stored in the cassette case can be confirmed from the outside. A window formed by fitting a transparent or translucent window member in the window opening is disposed. These windows are made of various resin materials according to impact strength, wear resistance, durability, and the like required for the magnetic tape cassette. For example, a window case made of AS (acrylonitrile styrene) resin is fitted to a case housing made of ABS (acrylonitrile butadiene styrene) resin, or a cassette case and a window member are all Various resins are used depending on the performance and shape required of the magnetic tape cassette, such as being formed of PS (polystyrene) resin, and are not formed of a uniform material.

For example, FIG. 65 shows a schematic perspective view of a general magnetic tape cassette.
As shown in FIG. 65, the magnetic tape cassette 90 includes an upper half 91 and a lower half 92 that constitute a cassette case serving as a casing. A slider 93 is attached to the lower surface side of the lower half 92, and a lid 94 is provided on the front side of the cassette (front side in the figure). The slider 93 is installed so as to be slidable in the front-rear direction of the cassette along the lower surface of the lower half 92. When the cassette is not used, the slider 93 closes the open portion on the lower side of the cassette case. The lid 94 is attached to the upper half 91 so as to be rotatable around a support shaft 94a so that the front side of the cassette can be opened and closed.

  In addition, a magnetic tape 95 wound around a pair of winding hubs is accommodated in the housing of the magnetic tape cassette 90. The upper half 91 is provided with a transparent window 96 for checking the remaining amount of tape when, for example, the magnetic tape cassette 90 is taken out of the deck (not shown) during use.

Each member of such a magnetic tape cassette is formed of a synthetic resin as described above. Specifically, for example, a member requiring slidability (abrasion resistance) is a resin molded POM (polyacetal), and in consideration of cost performance, the PS resin is Si (silicon). In addition, when considering the strength, ABS resin or the like is used.
In addition, the transparent window for checking the remaining amount of the tape provided on the video cassette or the like molded with ABS or the like is molded with AS or PMMA (polymethyl methacrylate) having adhesiveness with ABS. There were many cases. This is because the adhesion between the window and the cassette case by two-color molding (two-layer molding) and welding is considered.

Conventionally, molding of such a magnetic tape cassette, for example, molding of the upper half 91 and the window 96 is performed as follows.
As shown in FIG. 66 (a), the mold 100 for molding the upper half 91 and the window member 96 mainly includes an upper mold 102, a lower mold 104, and a movable (slide) core 106. Then, molten resin (for example, ABS (acrylonitrile butadiene styrene) resin or the like) is injected into a space 108 formed by the upper mold 102, the lower mold 104, and the movable core 106 to mold the upper half 91. is doing.

Next, as shown in FIG. 66 (b), the movable core 106 is moved downward by the thickness of the window member 96, and a transparent resin (for example, AS (acrylonitrile styrene) resin or the like) is placed in the resulting space 110. The window member 96 is molded by injection.
Conventionally, as shown in FIGS. 66 (a) and 66 (b), the end of the movable core 106 is cut obliquely (tapered), and the contact area between the window 96 and the upper half 91 is increased and bonded. Molded to increase the degree.

  Further, in such a magnetic tape cassette, the transparent window provided in the upper half of the cassette case is a perspective view in which the upper half is a cross-sectional view of the transparent window in FIG. As shown in the cross-sectional view taken along the window, the upper half 80 of the cassette case includes an opening 82a into which the transparent window member 84 is fitted into the upper half main body 82 serving as a base, and the periphery of the opening 82a. Is provided with a window frame 82b for supporting the window member 84, the window member 84 is fitted into the opening 82a of the upper half main body 82, and the window member 84 and the window frame 82b for supporting the window member 84 are ultrasonically welded. Manufactured by welding.

  The transparent window manufacturing method as shown in FIG. 67 and FIG. 68 is a manufacturing method that is easy to manufacture and suitable for mass production when manufacturing a cassette case. When disassembling the upper half 80 into the upper half main body 82 and the window member 84 and trying to recycle each as a new raw material, the transparent window 84 is welded to the upper half main body 82. It was very difficult to disassemble, and it was impossible to disassemble unless either the upper half body 82 or the window member 84 was destroyed.

  Even if one of these upper half body 82 or window member 84 is destroyed and disassembled, it is almost impossible to reliably separate upper half body 82 and window member 84 from the welded portion, A part of the window member 84 remains fixed to the upper half main body 82 or a part of the upper half main body 82 remains fixed to the window member 84. Therefore, when the upper half main body 82 and the window member 84 are to be recycled as new raw materials, a part of the window member 84 is included in the upper half main body 82, and a part of the upper half main body 82 is included in the window member 84. It was inevitable that the purity as a raw material would be reduced due to mixing with the part fixed.

  This transparent window constitutes a cassette case as a part of the upper half 80 and requires airtightness for dust prevention and the like, and is also portable, stored, and used for a recording / reproducing apparatus. Since handling such as loading is performed manually, there is a demand for sufficient strength that does not break or come off.

  In the case of a magnetic tape cassette molded by the molding method shown in FIGS. 66 (a) and 66 (b), as described above, conventionally, in order to maintain the strength of the cassette case, Adhesion is very strong, and usually a considerable amount of force is required to separate the window from the housing with human hands. Therefore, there is a problem that separation and recovery of ABS and AS or PMMA of different materials is difficult due to this strong adhesiveness. That is, a high peel strength is desirable from the viewpoint of securing the function, but there is a problem that the shape is not in consideration of the degradability of the product.

  In addition, for example, if a person forcibly separates a window from the housing and collects it, the window must be broken. If the window is not easily cracked cleanly, the broken window may be scattered and injured. There was also. However, there is also a problem that the dust-proof property of the cassette case cannot be ensured only by making the window easy to break by means such as simply making a cut (slit) in the window. Also, once strongly bonded windows are not easily cracked, and if they are forcibly destroyed, some of them remain stuck to the housing, which is better than before, but still completely meaning Then it is not separated. Also, when not separated and recovered, or when it cannot be completely separated in this way, because different materials are mixed, recycling as a recycled material (material recycling) is difficult, quality as a recycled material is poor, There was also a problem that it was difficult to sell as a recycled material, and it was necessary to improve the separation accuracy.

  Thus, in a magnetic tape cassette, it is desired to be able to easily separate the window from the housing while ensuring the dustproof property of the cassette case. Also, in general resin products, it is desired to increase the number of parts that can be recycled so that each part can be easily separated and collected.

In addition, as described above, in recent years, industrial products have been required to use limited earth resources effectively and consider the global environment. Therefore, as mentioned above, even for magnetic tape cassettes that are used in large quantities for a wide range of applications, the components or materials are recycled to save resources, and when they are discarded, the environmental load should not be increased. Is desired.
Generally, as a method of recycling the resin constituting the magnetic tape cassette, it is roughly classified into a method of recycling as it is as a member, component or resin material, so-called material recycling, and a method of using as fuel, so-called thermal recycling.

The former material recycling is less likely to cause problems in terms of resource saving and the environment, but thermal recycling is used as thermal energy, and the amount of heat released to the environment increases during the recycling process to prevent global warming. Is not effective. Therefore, it is desirable that there are few members, parts, or materials constituting the magnetic tape cassette that are inevitably subjected to thermal recycling or those that are inevitably subject to thermal recycling.
From these viewpoints, it is desirable that the window member fitted to the upper half of the magnetic tape cassette also does not cause resource saving, global environmental conservation, and global warming.

Accordingly, the present invention has been made in view of the above circumstances, and a first object of the present invention is to solve the above-mentioned problems of the prior art and to provide a base for a magnetic tape cassette discarded after use. When the upper half body and window member are disassembled, separated and separated, and recycled as raw materials for new products, they are easily and safely disassembled easily and efficiently, preferably without destruction. It is possible to use a base or window member obtained by disassembling a new product without causing a part of the window member to adhere to the base or a part of the base to the window member. Provided is a magnetic tape cassette having a transparent window having sufficient airtightness and strength, and thus having sufficient airtightness and strength, even when reused as a raw material, without being reduced in purity as a raw material. In the door.
In addition, another object of the present invention is to provide a magnetic tape cassette having a structure capable of performing a safe operation only when disassembling and separating the upper half body and the window member of the magnetic tape cassette discarded after use. There is to do.

  In order to achieve the above object, a magnetic tape cassette according to the present invention includes a resin base having an opening for forming a transparent window, and a transparent resin window member that closes the opening of the base. And at least the base and the window member using two types of resin materials that are not compatible with each other and are not adhesive to each other. Two-color molding is performed, and the base body and the window member after molding are combined from a predetermined direction.

According to the present invention, since the base material (upper half main body) and the window member constituting the transparent window of the magnetic tape cassette are not welded, disassembly is easy, and part of the window member is attached to the base material. Alternatively, a part of the base material does not remain fixed to the window member and can be completely separated, and when recycled and reused, the purity as a new raw material does not drop newly.
In addition, according to the present invention, in addition to this, even in the work of disassembling the base material and the window member, the window member can be easily and safely separated from the base material. It has a great effect.

  In other words, according to the present invention, a resin-made component of a magnetic tape cassette is obtained by a core back type two-color molding method using two types of resin materials that are not compatible with each other and are not adhesive to each other. (Substrate (upper half body) and window member) are molded in two colors at the same timing with a single mold, and after molding, each part is taken out and configured by combining each part. It becomes possible to easily separate and collect the above-mentioned parts of the tape cassette.

Also, in the first to twelfth related techniques of the present invention described later, since the base material (upper half body) and the window member constituting the transparent window of the magnetic tape cassette are not welded, disassembly is easy. In addition, a part of the window member does not remain attached to the base material or a part of the base material remains fixed to the window member, and can be completely separated. However, the purity as a raw material does not fall.
In addition, in the work of disassembling the base material and the window member, the window member can be easily and safely separated from the base material, which has a great effect on the safety of the operator. It is. The same effect as described above can be obtained.

  In addition, according to the first to twelfth related techniques of the present invention, even if a part of the discarded magnetic tape cassette is sent to thermal recycling, it is possible to reduce the heat radiation amount in thermal recycling. In addition, providing a magnetic tape cassette has the effect of being able to play. That is, according to each aspect of the present invention, it is possible to provide a magnetic tape cassette that reduces the amount of heat released during the recycling process and is effective in preserving the global environment and preventing global warming.

  A magnetic tape cassette according to the present invention will be described in detail below based on a preferred embodiment shown in the accompanying drawings.

First, with reference to FIGS. 1-8, the magnetic tape cassette which is the 1st related technique of this invention is demonstrated.
FIG. 1 is an exploded perspective view of a magnetic tape cassette having a transparent window according to the first related art of the present invention. FIG. 2 is a perspective view of the transparent window portion of the upper half of the magnetic tape cassette shown in FIG. FIG. 3 is a partial cross-sectional view of the upper half shown in FIG. FIG. 4 is a partially enlarged sectional view showing a state of engagement between the wedge-shaped (first) protrusion of the upper half body (base body) and the wedge-shaped (second) protrusion of the window member.

  In the magnetic tape cassette 10 having a transparent window according to the first related art, both end portions of a predetermined long magnetic tape 12 are fixed to a pair of winding hubs 14 and 14 as shown in FIG. The winding hubs 14 and 14 are wound from both ends. The pair of winding hubs 14 and 14 around which the magnetic tape 12 is wound are rotatably accommodated in a cassette case configured by combining the upper half 16 and the lower half 18. The magnetic tape 12 between the take-up hubs 14 and 14 is stretched through a predetermined path, and only the protruding portion 12a of the magnetic tape corresponding to the position of the magnetic head of the recording / reproducing apparatus (not shown) can be exposed to the outside. It is comprised so that.

  In order to cover and protect the magnetic layer surface of the overhanging portion 12a of the magnetic tape that can be exposed from the cassette case, the upper half 16 is provided with a front lid (lid) 22 pivotally supported by a pin 20 so as to be magnetic in the overhanging portion. The lid 22 is provided so as to swing between a closed position that covers the tape 12a and an open position that is exposed. The lid 22 is biased toward the closed position by a torsion coil spring (not shown).

  The lower half 18 has a bottom plate 24 having a rectangular shape, and a central portion of the bottom plate 24 rotatably supports a pair of winding hubs 14 and 14 around which the magnetic tape 12 is wound. When this magnetic tape cassette is loaded into a recording / reproducing apparatus (not shown), a reel shaft (not shown) protrudes from the recording / reproducing apparatus and is inserted into the winding hubs 14, 14. Reel shaft insertion holes 26 and 26 for rotational driving are provided.

  Further, the bottom plate 24 is formed with projecting portions 28, 28 extending forward from both left and right ends, and the left and right projecting portions 28, 28 are magnetic tapes stretched between the pair of winding hubs 14, 14. Cylindrical tape guides 30 and 30 for guiding 12 to the front surface of the cassette case through a predetermined path are erected vertically from the bottom plate 24. Between the left and right projecting portions 28 and 28, the lower half 18 It is a space where the bottom plate 24 does not exist and forms an opening of the cassette case.

  The tape guides 30 and 30 are positioned by inserting a positioning pin (not shown) protruding from the upper half 16, and screwed from below into a screw hole provided at the center of the positioning pin (also, It is also a screw boss for fixing the upper half 16 and the lower half 18 together. Also, screw bosses 32, 32 having the same structure are provided at the left and right corners behind the lower half 18, and a cassette in which the magnetic tape 12 and the like are assembled inside by tightening these four screws. The magnetic tape cassette 10 is configured by fastening the halves together.

  The slider 34 has a thin flat plate-like bottom plate 36 provided in contact with the bottom plate 24 of the lower half 18 from the lower side. The bottom plate 36 is an open portion on the lower surface side of the cassette case, that is, when the cassette is not used. The opening of the cassette case and the reel shaft insertion holes 26, 26 provided in the lower half 18 are closed for dust prevention, guided by the side walls 38, 38 of the lower half 18, and The cassette case is slidable in the longitudinal direction of the cassette along the lower surface, and the cassette case opening and the reel shaft insertion holes 26 and 26 are closed by the bottom plate 36 by moving forward, and the cassette case by moving backward. And the positions of the reel shaft insertion holes 36, 36 of the lower half 18 and the reel shaft insertion holes 40, 40 of the slider 34 coincide with each other. Reel shafts of the recording and reproducing apparatus can be inserted.

  The bottom plate 24 of the lower half 18 is provided with an intermediate wall 42 that is curved in an arc shape along the magnetic tape 12 wound around the winding hub 14, and is formed at a central connection portion of the intermediate wall 42. A leaf spring mounting portion 44 is erected in front of the recessed portion, and a slider spring 46 made of a leaf spring is inserted between the recessed portion formed in the central connecting portion of the intermediate wall 42 and the leaf spring mounting portion 44. The rib 48 provided in front of the slider 34 is pressed forward (in the direction in which the slider 34 closes).

  Gears 50 and 50 are respectively provided at the centers of the pair of winding hubs 14 and 14, and brake pieces 54 and 54 of a brake member 52 provided on the upper half 16 are engaged with the gears 50 and 50. Thus, a rotation prevention mechanism for the take-up hub that locks the take-up hubs 14 and 14 from rotating when the magnetic tape cassette 10 is not used is formed. A transparent window for visually recognizing the winding amount of the winding hubs 14 and 14 is formed in the upper half 16, and this transparent window has an opening formed in the upper half body 56. A window member 58 made of a transparent resin (plastic) is attached to the opening.

  FIG. 2 is a perspective view in which the transparent window portion of the upper half 16 of the magnetic tape cassette 10 described above is sectioned along the line II in FIG. As is clear from the drawing, the transparent window of the upper half 16 includes an opening 56a formed as a window in the upper half body 56 of the upper half 16, and a window made of a transparent resin attached to the opening 56a. And a member 58.

As shown in FIGS. 3 and 4, the details of the opening 56 a formed in the upper half main body 56 are wedge-shaped first on the inner peripheral portion of the opening 56 a forming the transparent window of the upper half main body 56. One projection 56b is provided. On the other hand, the window member 58 has a shape that fits into the upper half main body 56, and is provided with a wedge-shaped second protrusion 58a on the outer peripheral portion thereof.
Further, the wedge-shaped projection 56b of the upper half body 56 and the wedge-shaped projection 58a of the window member 58 are formed by pressing the window member 58 from above as shown in FIGS. 4 (a) and 4 (b). When mounting, both wedge-shaped projections are elastically deformed to pass through, and after mounting, they are formed in a wedge shape so that they do not engage and disengage. The wedge-shaped projections 56b of the upper half body 56 and the wedge-shaped projections 58a of the window member 58 are intermittently arranged at the same position so as to engage with each other.

  As shown in FIG. 4A, when the wedge-shaped projections 56b and 58a are formed so as to be in close contact with each other, the window member 58 is most difficult to come off. The window member 58 may be rattled without being able to be reliably engaged or without being in close contact. In order to prevent this, as shown in FIG. 4B, at least one of the engagement surfaces is inclined so that the engagement cannot be ensured and the window member 58 does not adhere to the upper half 56. It is possible to prevent the rattling from occurring. The angle of the inclined surface can be determined to an appropriate angle in consideration of variations in the dimensions of the wedge-shaped protrusion 56b of the upper half body 56 and the wedge-shaped protrusion 58a of the window member 58.

  According to the first related art, when the upper half main body and the window member are disassembled and recycled, the upper half or the window member obtained by disassembling can be easily disassembled as a new raw material. As a result, it is possible to realize a magnetic tape cassette that does not deteriorate in purity even when reused and that can be efficiently disassembled.

  FIG. 5 is a cross-sectional view of the upper half of the magnetic tape cassette according to the second related technology of the present invention, and FIG. 6 shows the state of engagement between the window frame of the upper half main body and the claw member of the window member. It is an expanded sectional view. This configuration example shows another implementation example of the engaging means for engaging the opening 56a formed in the upper half main body 56 of the magnetic tape cassette with the window member 58.

  That is, in the magnetic tape cassette according to the second related technology, the window frame 56c is provided on the inner peripheral portion of the opening 56a formed in the upper half body 56, and the window member 58 is provided with the window frame 56c. A locking claw 58b is provided to hold and hold 56c. Then, when the window member 58 is pressed and attached from above, the locking claw 58b of the window member 58 snaps into engagement with the window frame 56c of the upper half body 56, and the opening 56a of the upper half body 56 is engaged. A window member 56 is attached to the door.

  As shown in FIGS. 6A and 6B, the shape of the locking claw 58b is such that the window frame 56c formed on the lower side of the inner peripheral portion of the opening 56a of the upper half body 56 has a window The engaging claw 58b of the member 58 is engaged so as to sandwich and hold the window frame 56c. Usually, as shown in FIG. 6A, the lower surface of the upper half main body 56 and the window frame 56c. The lower surface of the film is formed at the same height.

However, since the locking claw 58b of the window member 58 protrudes from the lower surface of the upper half body 56, when this projection is disliked, the lower surface of the window frame 56c is lower than the lower surface of the upper half body 56 as shown in FIG. A groove is formed so as to be low, and an engagement surface of the window frame 56c is provided inside the groove, and a locking claw 58b of the window member 58 is also lowered by the same height, and an appropriate groove is provided around the groove. Thus, a structure in which the locking claw 58b does not protrude from the lower surface of the upper half body 56 can be achieved.
Similarly to the first related art, by making at least one of the engagement surfaces of the window frame 56c and the locking claw 58b into an inclined surface, it is possible to achieve a configuration that can be reliably engaged and has excellent adhesion. It is.

  Also according to the second related technology, when the upper half main body and the window member are disassembled and recycled, it can be easily disassembled, and the upper half or window member obtained by disassembling is used as a new raw material. It is possible to realize a magnetic tape cassette that does not deteriorate in purity even when reused and that can be efficiently disassembled.

  FIG. 7 relates to a third related technique of the present invention, and shows an engaging means for engaging an opening 56 a formed in the upper half main body 56 and the window member 58. The window-shaped member 58 is engaged with the wedge-shaped protrusion 56 b provided on the inner peripheral portion of the opening 56 a formed in the upper half body 56 and the wedge-shaped protrusion 58 a provided on the outer peripheral portion of the window member 58. The engaging claw 58b provided on the window member 58 snap-fits the engaging means shown in the first related art for holding the window frame 56c formed on the lower side of the opening 56a of the upper half body 56. And the second related technology to be held.

  Here, in FIG. 7, the wedge-shaped projections 58a provided on the outer peripheral portion of the window member 58 and the locking claws 58b are drawn at the same position, but in actuality, they are shown in FIG. As shown in the perspective view of the window member 58, it is desirable that the wedge-shaped projections 58a and the locking claws 58b provided on the outer periphery of the window member 58 are arranged in different positions. And, by configuring like this third related technology, it has the advantages of both the first related technology and the second related technology, and can obtain a transparent window with better adhesion. it can.

Next, a magnetic tape cassette according to the fourth related technique of the present invention will be described with reference to FIGS.
In the present technology, the transparent window provided in the upper half of the magnetic tape cassette is characterized in that the window member constituting the transparent window is fixed by being obliquely press-fitted into the opening of the upper half body serving as a base. The magnetic tape cassette according to the related art is shown in FIG. 1 except for the mounting and fixing mechanism of the window member constituting the upper half transparent window and the opening of the upper half main body to which the window member is mounted. Since this has the same configuration as the magnetic tape cassette shown, only this mechanism will be described in detail below, and the other description will be omitted.
FIG. 9 is an enlarged perspective view showing one configuration example of the window member locking portion provided in the upper half of the magnetic tape cassette according to the fourth related technique of the present invention. FIG. 10 is a perspective view showing a configuration example of a window member having a locking member that is locked to the upper half window member locking portion shown in FIG. 9.

  First, in the window member 178 of the magnetic tape cassette according to the fourth related technique shown in FIG. 10, the locking member 178a is provided on one of the two opposite sides of the window member 178, and the dust-proofing is provided on the other two sides. A stepped portion 178b for use is formed. Further, here, the dust prevention on the two sides where the above-described locking member 178a is provided is dealt with by providing the window member 178 with a dust prevention collar (178). In FIG. 10, the upper surface of the figure is the outer surface side of the upper half of the magnetic tape cassette.

  Further, the window member 178 according to the fourth related technique shown in FIG. 10 is shown on the opposite side of the dust-proof collar 178c by partially extending (178d) the above-mentioned collar so that the window member 178 is moved upward. It shows that the reel spring that presses the reel around which the magnetic tape is wound in the lower half direction when being fitted into the opening of the half main body 176 can also be used to sandwich the reel spring with the upper half. .

  Then, according to the fourth related technique shown in FIG. 9, the locking member 178a of the window member 58 is locked to the window member locking portion (periphery of the opening) of the upper half 176 corresponding to the window member 178. And a stepped portion 176b corresponding to the stepped portion 178b are formed. The locking member 178a and the locking groove 176a, and the stepped portion 178b and the stepped portion 176b engage with each other. By doing so, it is comprised so that the effect | action of a latching and dust prevention may be implement | achieved.

  In the window member locking portion and the window member locking mechanism according to the fourth related technique shown in FIGS. 9 and 10, the locking member 178a of the window member 178 is inclined from the inner surface side of the upper half 176 of the magnetic tape cassette. 9 is inserted into the locking groove 176a of the window member locking portion shown in FIG. 9, and the window member 178 is locked to the window member locking portion of the upper half 176 by applying a force along this direction. Can be made. As will be described later, at the final stage of this locking operation, the stepped portion 178b of the window member 178 and the stepped portion 176b of the window member locking portion of the upper half 176 are fitted in a substantially vertical direction. It will be.

  As described above, the window member locking operation according to the fourth related technology that acts in two stages, so to speak, makes the window member locking portion according to this related technology strong against relatively simple fitting operation. The fitting can be realized, and when disassembling, the original locking member is first applied by a predetermined oblique direction force after first releasing the locking of the stepped portion by a vertical direction force. And the safety measure of releasing the locking by the locking groove stands out.

  This will be described more specifically with reference to FIG. 11 is a cross-sectional view taken along an imaginary center line II-II in FIG. 9 in a state where the window member 178 is locked to the window member locking portion of the upper half 176. FIG. As shown in detail in FIG. 11, first, in a state where the window member 178 is locked to the window member locking portion of the upper half 176, the stepped portion side surfaces 179a, 179b (upper) of the window member 178 and 180a, 180b (lower stage) and the stepped portion side surfaces 181a, 181b (upper stage) and 182a, 182b (lower stage) of the window member locking portion of the upper half 176 are in contact with each other, whereby the window member 178 is in the upper half 176 Is accurately positioned with respect to the (window member locking portion).

  At the same time, when removing the window member 178 from the upper half 176 (the window member locking portion thereof), as described above, basically it can be removed only from a predetermined oblique direction, but the horizontal component of the force in the oblique direction is The window member 178 is pressed in the vertical direction from the outer surface of the upper half (downward in the drawing) to release the restriction, and thus the force from the oblique direction described above. If you do not add, you can not remove.

FIGS. 12A to 12C are schematic views illustrating a situation where the window member 178 is fitted into the window member locking portion provided in the upper half 176. FIG.
In the fourth related technique, when the window member is fitted into the window member locking portion, the window member 178 is continuously formed along a predetermined inclination angle as shown in FIGS. May be inserted into the window member locking portion provided in the upper half 176.

FIGS. 13A to 13C are schematic views illustrating a situation in which the window member 178 is removed from the window member locking portion provided in the upper half 176. FIG.
When removing the window member from the window member locking portion, as shown in FIG. 13 (a), first, one end portion of the window member 178 is pushed upward vertically, and then, FIG. As shown in c), it may be pulled up along the same predetermined inclination angle as that at the time of fitting.

  In addition, accompanying the above-described fitting operation of the window member 178, the stepped portion 178b of the window member 178 is engaged with the stepped portion 176b, and dust prevention around the window member 178 is also realized. Further, the flange 178c of the window member 178 realizes the dustproofing action of the remaining portion around the window member 178 (the side surface with the locking member 178a).

  In FIG. 14, the structural example of the shape of the latching member 178a provided in the side surface of the window member 178 is enumerated. In FIG. 14, (a) is a standard rectangular shape with both ends rounded, (b) is the shape shown in (a) with the side face shaved to facilitate insertion, (c) is a further narrowed tip side at the time of insertion, and (d) is one in which the length at the time of insertion is shortened to facilitate the insertion.

  Since the magnetic tape cassette according to this aspect is configured as described above, when the magnetic tape cassette is used, the locking member 178a provided on the window member 178 and the opening of the upper half main body 176 are provided. Since the stepped portion 176b provided in the opening of the upper half main body 176 and the stepped portion 178b provided in the window member 178 are closely attached and engaged with the locking groove 176a, the bonding strength and There is no practical problem with airtightness.

  In the fourth related technique shown in FIGS. 9 and 10, the engagement angle between the locking member 178 a provided in the window member 178 and the locking groove 176 a provided in the opening of the upper half body 176. Is not clearly defined, but it is usually preferable to be inclined about 10 to 45 ° from the vertical direction. Here, the direction of the inclination is preferably one of the longitudinal directions of the upper half body 176.

  FIG. 15 is a diagram showing further details of the locking groove 176a of the window member locking portion provided in the upper half main body 176 according to the fourth related technique shown in FIG. As shown in FIG. 15, the entrance side 176aa (right side in the drawing) of the locking groove 176a is a somewhat gentle guiding portion so as to facilitate the insertion of the locking member 178a provided on the window member 178. On the contrary, the outlet side 176ab (left side in the drawing) of the locking groove 176a is not easily detached from the pressing force from the direction close to the vertical. Therefore, it is preferable to maintain a precise predetermined angle.

  FIGS. 16A and 16B are detailed sectional views showing still another configuration example of the locking groove 176a of the window member locking portion provided in the upper half main body 176. FIG. Here, FIG. 16A shows a shape of a locking groove that is effective when a locking member having a short cross-section as shown in FIG. Is shown. In this case, it is preferable to move the window member by a small amount downward in the vertical direction after fitting at a predetermined inclination angle.

Further, the example shown in FIG. 16B also shows the shape of the locking groove that is effective when a locking member having a short length in the insertion direction is used. In this case, it is preferable to first insert a small angle in the vertical direction and then insert it at a predetermined inclination angle.
As the shape of the locking groove 176a of the window member locking portion, various other shapes such as a combination thereof can be adopted.

  FIG. 17 shows another configuration example of the shape in the vicinity of the locking groove 176a of the window member locking portion. In the example shown here, the above-described locking groove 176a is further extended on the 176aa side (extension portions, 176ac, 176ac) to improve locking reliability.

In this related technology, in addition to the above configuration example, it is also possible to adopt a locking claw having another structure, and various types for visually confirming the inside provided in other types of magnetic tape cassettes. Obviously, the same applies to transparent windows.
For example, in the above configuration example, the window member 58 is provided with two locking members 58a on the left and right. However, if the number of the locking members 58a is one or more on the left and right, the magnetic tape It may be arbitrarily determined according to the size of the cassette or the size of the window. Further, the width and depth of the stepped portions 58b and 56b provided in the window member 58 and the upper half main body 56 may be arbitrarily determined.

Next, a magnetic tape cassette according to a fifth related technique of the present invention will be described with reference to FIGS.
Note that the magnetic tape cassette according to the related art also has substantially the same configuration as the magnetic tape cassette shown in FIG. 1 except for the structure of the transparent window of the upper half. Hereinafter, only this structure will be described. This will be described in detail, and other descriptions will be omitted.
FIG. 18 shows a configuration example of the transparent window of the cassette case according to the related technique, and is a cross-sectional view in the longitudinal direction of the transparent window portion of the upper half. FIG. 19 is a cross-sectional view in a direction orthogonal to this. As is clear from these drawings, the upper half transparent window is made of an opening 206a formed as a window in the upper half main body 206, and a transparent resin mounted so as to close the opening 206a. And a window member 208.

As shown in FIG. 18 (cross-sectional view in the longitudinal direction of the transparent window), the cross-sectional shape of the joint between the opening 206a of the upper half body 206 and the window member 208 is V-shaped at both ends in the longitudinal direction. The protrusions and the recesses are joined to each other. That is, the left side cross-sectional shape of the opening 206a of the upper half body 206 is provided with a concave portion 206b that is lowered by one step from the upper surface, and an inclined surface 206c that is lowered to the left is provided below the concave portion 206b. A V-shaped protrusion 206d is formed by the surface of the recess 206b and the inclined surface 206c.
The above-mentioned V shape refers to a state where two surfaces are opposed to each other at an angle, and at least one surface is parallel to the surface of the upper half body, and the other surface is In contrast, it has a predetermined angle. Further, the predetermined angle refers to an angle within a range where it can be smoothly inserted when pressed, and is usually preferably 30 ° or more.

  On the other hand, the left sectional shape of the window member 208 attached to the opening 206a of the upper half body 206 corresponds to the sectional shape of the opening 206a of the upper half body 206, and the concave portion of the upper half body 206 is on the upper side. A flange 208a to be fitted into 206b is provided, and an inclined surface 208b corresponding to the inclined surface 206c of the upper half main body 206 is provided on the lower side thereof, and the upper half is formed by the lower surface of the flange 208a and the inclined surface 208b. The same V-shaped recess 208c corresponding to the V-shaped protrusion 206d of the main body 206 is formed.

  Further, the right side cross-sectional shape of the opening 206a of the upper half main body 206 is opposite to the left cross-sectional shape, and an inclined surface 206e is provided on the upper side of the opening 206a of the upper half main body 206, and a concave portion 206f is provided on the lower side. Is provided with a V-shaped protrusion 206g, and the window member 208 has a sectional shape 208d corresponding to the inclined surface 206e of the upper half body 206 on the upper side and an upper half on the lower side. A flange 208e to be fitted into the recess 206f of the main body 206 is provided, and the same V-shaped recess 208f corresponding to the V-shaped protrusion 206g of the upper half main body 206 is formed. As shown in FIG. 19, the cross-sectional shape perpendicular to the longitudinal direction of the joint portion of the transparent window is provided with a recess 206h above the opening 206a of the upper half body 206, and a window member 208 is provided in the recess 206h. The flange 208g is fitted.

  Since the cross-sectional shape of the joint between the opening 206a of the upper half body 206 and the window member 208 in this configuration example is thus formed in a shape that combines two sets of inclined V-shapes, the window member When assembling 208 into the opening 206a of the upper half main body 206, the protrusion 206g and the flange 208e are elastically deformed and easily assembled by combining the left joint and pressing strongly from above.

  Once the upper half body 206 and the window member 208 are assembled, both ends in the longitudinal direction of the transparent window are, as shown in FIG. 18, the V-shaped protrusion 206d of the upper half body 206 and the V-shape of the window member 208. The cross-sectional shape orthogonal to the longitudinal direction of the transparent window is shown in FIG. 19 while the V-shaped protrusion 206g of the shape recess 208c and the upper half body 206 and the V-shaped recess 208f of the window member 208 are in close contact with each other. As shown, the flange 208g of the window member 208 is in close contact with the recess 206h provided on the upper side of the opening 206a of the upper half body 206, thereby providing sufficient airtightness and from the outside (upper side in the drawing). It can have sufficient strength against force.

  When disposing the upper half main body 206 and the window member 208 when disposing the magnetic tape cassette after use, as shown by the arrows, the right end of the window member 208 is directed from the inside (lower side in the figure) to the upper left direction. The flange 208g of the window member 208 is disengaged from the V-shaped protrusion 206g of the upper half main body 206, and can be disassembled without destroying the upper half main body 206 and the window member 208. . Here, a mark that can be easily understood by the user or the discarder, such as “PUSH”, is described at the pressing position, or an arrow indicating the pressing direction is described, so that the method of disassembling can be shown more reliably.

  FIG. 20 shows still another configuration example of the related technology, in which the flange 208a (208e) of the window member 208 and the V-shaped recess 208c (208f) are alternately and intermittently provided. is there. By comprising in this way, an undercut does not arise in the metal mold | die which shape | molds the window member 208, the structure of a metal mold | die becomes a simpler structure, and the window member 208 can be manufactured cheaply. . Of course, in this case, in order to improve the appearance quality of the magnetic tape cassette, the recesses 206b and 206f and the V-shaped protrusions 206d and 206g in the opening 206a of the upper half main body 206 are also formed in a shape corresponding thereto. It is desirable. Moreover, this V shape should just be provided in at least one place, and does not need to be provided over the whole width of a window.

  Since the transparent window of the cassette case according to the related art is configured as described above, unlike the conventional technique in which the window member is simply fitted and welded, the opening of the upper half body and the window member are joined. Since the cross-sectional shape of the part is formed in an inclined V shape, it can be assembled without welding, it is substantially immovable after assembly, has sufficient airtightness, and from the outside It is possible to have a sufficient strength against this force. When disposing the upper half main body and the window member when disposing the magnetic tape cassette after use, the window member is pushed obliquely from the inner side (lower side) to remove the window member from the upper half main body. It can be reliably disassembled without breaking from the opening.

Next, a resin molded product according to the sixth related technique of the present invention will be described with reference to FIGS.
In the following, the resin molded product according to the related technology will be described in detail by taking a representative example of a magnetic tape cassette in which a transparent window for checking the remaining amount of the magnetic tape is incorporated in a separable manner. It goes without saying that it is not limited.
FIG. 21 shows a configuration example of a magnetic tape cassette according to the related art. As shown in FIG. 21, the magnetic tape cassette 230 according to this related technology includes an upper half 231 and a lower half 232 that constitute a casing (cassette case). A slider 233 is attached to the lower surface side of the lower half 232, and a lid 234 is provided on the front side of the cassette (front side in the figure). In this related art, the configuration of the magnetic tape cassette not shown in FIG. 21 is the same as that of the magnetic tape cassette shown in FIG.

  Further, the magnetic tape wound around the pair of winding hubs is accommodated in the housing of the magnetic tape cassette 230. For example, when the magnetic tape cassette 230 is removed from a deck (not shown) during use, a transparent window member (hereinafter, the window member is simply referred to as a window) 236 for checking the remaining amount of the tape is provided. The upper half 231 is installed in a window receiving portion (window member receiving portion) 237 so that it can be easily separated and recovered.

  In the present configuration example, in order to facilitate the separation and collection of the window 236, the projections 238 (238a, 238b, 238c, 238d). In order to make the arrangement and shape of the protrusions 238 easier to understand, FIG. 22 is a cross-sectional view taken along line III-III in FIG. 21, and FIG. 23 is a cross-sectional view taken along line IV-IV.

As shown in FIG. 22, protrusions 238 a and 238 b are provided on the opposite end surfaces 237 a and 237 b of the window receiving portion 237 of the upper half 231 so as to alternate with each other, and the window 236 is sandwiched from above and below. Similarly, the protrusions 238c and 238d also sandwich the window 236 from above and below.
Further, as shown in FIG. 23, protrusions 238a, 238d and the like are arranged in a staggered manner on one end surface 237a of the window receiving portion 237 of the upper half 231 with the window 236 sandwiched from above and below.

  FIG. 24 is an enlarged perspective view of the vicinity of the protrusions 238b and 238c of the window receiving portion 237 of the upper half 231 of FIG. As shown in FIG. 24, protrusions 238b, 238c, etc. are formed on the end surface 237b of the window receiving portion 237 so that the window 236 can be inserted therebetween with a gap d corresponding to the thickness of the window 236. Alternately, they are arranged in a staggered pattern.

  FIG. 25 shows a state where the window 236 is actually incorporated in the window receiving portion 237 of FIG. Thus, the window 236 is installed in the upper half 231 by inserting the window 236 having the thickness d between the protrusions 238b and 238c. At this time, if the vertical distance d between the protrusions 238b and 238c is set slightly smaller than the thickness of the window 236, the window 236 is firmly fixed to the upper half 231 and does not come off by a slight impact.

The shape of the window 236 is not a simple rectangular plate shape, but is preferably a stepped rectangular shape in which two large and small rectangles are connected as shown in FIG. Naturally, the window receiving portion 237 also has a shape that matches the shape of the window 236. Then, the window 236 having such a shape is inserted into the window receiving portion 237 of the upper half 231 from the side having a smaller width as shown by an arrow A in FIG.
Conversely, when removing the window 236 from the upper half 231, as shown by the arrow B in FIG. 27, if the window 236 is pushed from the small side of the window 236, the window 236 can be easily separated and recovered from the upper half 231. Can do.

  As shown in FIG. 26, the window 236 may have a uniform thickness as a whole, but as shown in FIG. 28, the window 236 is made slightly thicker than the inter-projection spacing d shown in FIG. You may make it provide the shallow recessed part 236a, 236b etc. in the part which hits each projection part 238. FIG. By doing so, the recesses 236a and the like and the projections 238 are engaged to prevent the window 236 from shifting in the lateral direction, and the window 236 and the upper half 231 are more securely fixed.

  Further, the shape of the window 236 is not limited to the stepped rectangular shape as described above, and the opposite side (arrow B side) is closer to the window insertion side (arrow A side) shown in FIG. For example, a trapezoidal shape may be used. That is, when the window 236 is inserted into the window receiving portion 237, it is only necessary to stop at a predetermined position without penetrating through the other side. Therefore, the window 216 may have a simple rectangular shape as long as the engagement between the protrusion 238 and the recess (236a, etc.) shown in FIG.

  Further, the shape of the window receiving portion 237 does not have to be opened completely through the longitudinal direction of the upper half 231 from end to end, and the arrow B side in FIG. 27 is closed without being opened. Also good. In this case, when separating and collecting the window from the upper half 231, it is only necessary to apply a force from above to the window and push it toward the side from which the window is detached.

According to this configuration example, it is easy to attach and remove the window to the upper half of the magnetic tape cassette, and the housing and the window, which are different materials, can be easily separated and collected.
In the above description, the upper half of the magnetic tape cassette and the window are separated and recovered as an example. However, the same idea is applied to a resin molded product composed of parts of the same different materials. Thus, parts of different materials can be easily separated and collected, and the parts can be easily recycled.

Next, with reference to FIGS. 29-35, the magnetic tape cassette based on the 7th related technique of this invention is demonstrated.
In addition, in the magnetic tape cassette according to this related technology, except for the structure of the upper half transparent window and its mounting structure, it has substantially the same configuration as the magnetic tape cassette shown in FIG. Only these structures will be described in detail, and other descriptions will be omitted.
FIG. 29 is a perspective view showing the upper half of one configuration example of the magnetic tape cassette according to the related art. FIG. 30 is a cross-sectional view taken along the line VV of the upper half in FIG. FIG. 31 is a side view showing the window member shown in FIG. 30. FIG. 32 is a perspective view of the window member shown in FIG. 31 as viewed from below. As is clear from these figures, the transparent window of the upper half 250 according to this configuration example is provided in the upper half body 256 of the upper half 250, and two circular openings 256a formed as windows, It comprises a circular window member 258 made of two transparent resins attached to the opening 256a.

  A window member 258 having the shape shown in FIGS. 31 and 32 is attached to the opening 256 a formed in the upper half body 256. The window member 258 shown in this configuration example is provided with a screw-like screwed portion 260 on the outer periphery that fits into the opening 256 a of the upper half main body 256. In addition, the opening 256 a of the upper half body 256 is provided with an engaging portion 262 that engages with a screw-like screwed portion 260 provided on the outer periphery of the window member 258. The engagement portion 262 may be a screw having the same pitch as that of the screw-like screw portion 260 of the window member 258. However, a pin-like protrusion is used, and the screw portion 260 is allowed to pass through the protrusion at the time of mounting. The window member 258 can be attached and detached more easily by providing a well-known bayonet structure by providing the gap 264 in the window.

  Further, it is desirable to provide a flange 266 on the upper side of the window member 258 so that the window member 258 is attached and firmly fixed to maintain airtightness. In this case, it is desirable to provide a step in the opening 256 a of the upper half body 256 so that the window member 258 does not protrude from the upper half body 256. Furthermore, it is desirable to provide a groove 268 on the bottom surface of the window member 258 that is inserted and rotated when a window member 258 is attached to the upper half main body 256.

  The groove 268 is also used when disassembling and separating the upper half body 256 and the window member 258 when the magnetic tape cassette is discarded after use. In order to prevent the window member 258 from being accidentally disassembled when the magnetic tape cassette is used, it is desirable to provide the groove 268 on the bottom surface side of the window member 258. The groove 268 may be provided with a remaining tape scale. On the contrary, when it is not preferable that the groove 268 is seen with the remaining amount of the tape when the inside of the magnetic tape cassette is visually confirmed, the groove 68 is replaced with the groove 68. Two holes or the like provided in the outer peripheral portion can be used.

  According to the above configuration example, the upper half body and the window member of the magnetic tape cassette discarded after use are disassembled and separated, and can be easily and safely disassembled when recycled as raw materials for new products. Therefore, a magnetic tape cassette having a transparent window can be provided.

  FIG. 33 is a view showing a transparent window portion of another configuration example of the magnetic tape cassette according to the related technology, (a) is a perspective view of a window member constituting the transparent window, and (b) It is the side view. 34 is a partial perspective view showing an opening portion of the upper half to which the window member shown in FIG. 33 is mounted, and FIG. 35 is a window member and an inner peripheral surface of the opening portion of the upper half in the configuration example shown in FIG. It is a figure explaining the engagement condition.

  In the engagement method of the transparent window portion of the magnetic tape cassette according to this configuration example, the engagement portion formed of a part of a spiral on the inner peripheral surface of the upper half opening is opposite to the method shown in the previous configuration example. 274, and an engaging projection 272 is provided on the outer peripheral surface of the window member 270. In the transparent window portion of the magnetic tape cassette according to this configuration example configured as described above, the window member 270 can be easily assembled and disassembled in the same manner as the method shown in the previous configuration example.

  That is, according to the above configuration example, the upper half body and the window member of the magnetic tape cassette discarded after use are disassembled and separated, and easily and safely disassembled when recycled as raw materials for new products. A magnetic tape cassette having a transparent window can be provided.

Next, a magnetic tape cassette and a method for manufacturing the magnetic tape cassette according to the eighth related technology of the present invention will be described with reference to FIGS.
In addition, in the magnetic tape cassette according to this related technology, except for the structure of the upper half transparent window and its mounting structure, it has substantially the same configuration as the magnetic tape cassette shown in FIG. Only these structures will be described in detail, and other descriptions will be omitted.
36 is a perspective view showing one structural example of the upper half of the magnetic tape cassette according to the related art, and FIG. 37 is a cross-sectional perspective view of the upper half in FIG. 38 and 39 are cross-sectional views taken along the line VII-VII of the upper half and the window member in FIG. 37, respectively. In the present configuration example, as is clear from these drawings, the transparent window 306 includes an opening 300a formed as a window in the upper half 300 and a window member made of a transparent resin attached to the opening 300a. 306.

  As shown in FIG. 38, the cross-sectional shape of the opening 300a formed in the upper half (upper half main body) 300 is such that the upper window frame 300b formed thick enough to have sufficient rigidity and elastically deformable. The lower window frame 300d is formed thin, and a groove 300c for inserting the window member 306 is formed between the upper window frame 300b and the lower window frame 300d. It has a shape. Here, in the related technique shown in FIG. 38, the thickness of the lower window frame 300d is constant, but it may be formed partially thin in order to facilitate elastic deformation.

  On the other hand, the shape of the window member 306 attached to the opening 300a formed in the upper half 300 is the same as the shape of the groove 300c in the opening 300a of the upper half 300, as shown in FIG. For this reason, the thickness is slightly smaller, and the thickness is the same as the width of the groove 300c in the opening 300a of the upper half 300, or is formed slightly thinner to facilitate insertion. The window member 306 is provided with a protrusion 306a at a position where the window member 306 contacts the lower window frame 300d when inserted into the groove 300c of the upper half 300.

  In the magnetic tape cassette according to this configuration example, the dismountable transparent window can be attached as a first step when the transparent window member 306 is attached to the upper half 300 formed as described above. The window member 306 is inserted into the groove portion 300c of 300 and temporarily joined. At this time, since the protrusion 306a of the window member 306 is provided at a position where it abuts on the lower window frame 300d of the upper half 300, the lower window frame 300d is elastically deformed as shown in FIG. Temporary joining is performed in a state of being held by the upper half 300.

  Next, as a second step, a welding operation using ultrasonic waves or heat is performed on the temporary joint portion where the lower window frame 300d is elastically deformed and holds the window member 306. However, the material of the upper half 300 and the material of the window member 306 are not compatible or compatible as in the case where the material of the upper half 300 is ABS resin and the material of the window member 306 is transparent PS resin. In the case of a material having low solubility, the upper half 300 and the window member 306 (particularly, the protrusion 306a) are not welded by the welding operation using ultrasonic waves or heat. The joint surface (protrusion 306a) is only crushed and deformed. This situation is shown in FIG.

  That is, the elastic deformation of the lower window frame 300d is eliminated by the above-described ultrasonic wave or heat welding operation, but the upper half 300 and the window member 306 are not welded and contact each other without a gap. In order to use it as a transparent window of a magnetic tape cassette in a state where it cannot be moved (pinched / fixed), it becomes the same as the transparent window of the prior art and can be used without any trouble. The protrusion 306a may be provided not on the window member 306 but on the upper half 300 side.

  On the other hand, when the cassette case manufactured in this manner is disassembled after being used and the upper half 300 and the window member 306 of the cassette case are disassembled and recycled as new raw materials, the upper half 300 and the window member. Since 306 is not welded, the window member 306 can be easily taken out by deforming the lower window frame 300d of the upper half 300 by strongly pressing the window member 306 from above. In this case, when the window member 306 is pushed out from the lower window frame 300d, even if the deformation of the lower window frame 300d is insufficient and the window member 306 is damaged, the upper half 300 and the window member 306 are not welded. The damaged window member 306 can be easily taken out from the groove 300c of the upper half 300.

Further, the upper half 300 and the window member 306 disassembled in this way are not welded to the upper half 300 and the window member 306, so that a part of the window member 306 or the window member 306 is not attached to the upper half 300. A part of the half 300 does not remain fixed, and the upper half 300 and the window member 306 can be completely separated, and when recycled and reused, the purity as a new raw material is newly reduced. The effect that there is nothing is obtained.
Further, even in the operation of disassembling the upper half 300 and the window member 306, since the upper half 300 and the window member 306 are not welded, the window member 306 can be easily removed from the upper half 300 of the cassette case as described above. Even if the window member 306 is damaged, since the upper half 300 and the window member 306 are not welded, the damaged window member 306 can be easily taken out from the groove portion 300c of the upper half 300. Since it can, it can be disassembled safely.

FIG. 42 is a perspective view of the magnetic tape cassette according to still another configuration example of the related art in a cross-sectional view at the transparent window portion of the upper half of the magnetic tape cassette. The difference from the configuration example shown above is that the upper window frame 300b of the opening 306a formed in the upper half 300 for sandwiching and fixing the window member, and the lower window formed thin so as to be elastically deformable Each of the frames 300d is not continuous but has a shape dispersed in a plurality of places.
Also with the magnetic tape cassette according to the related technology, the same effect as that obtained in the related technology described above can be obtained.

By the way, in the manufacturing method of the magnetic tape cassette according to the related technology for manufacturing the magnetic tape cassette according to the above configuration example, the window member 306 is not compatible with the material of the upper half 300 serving as the base or is extremely compatible. In order to insert the window member 306 between the upper window frame 300b having sufficient rigidity and the lower window frame 300d capable of being elastically deformed, at least part of the opening 300a of the upper half 300 is molded with a low material. The upper half 300 is molded so as to have a groove portion 300c serving as a temporary fitting portion, and at this time, the upper window frame 300b or the lower window frame 300d of the opening 300a of the upper half 300, or the window member 306 is an upper window frame. A protrusion (protrusion 306a on the window member 306 side in the illustrated example) is provided at a position where 300b or the lower window frame 300d and the window member 306 contact each other. The window member 306 is inserted into the groove portion 300c of the opening 300a of the upper half 300, the lower window frame 300d is elastically deformed and temporarily joined, and an ultrasonic wave or ultrasonic wave is applied to the temporarily joined portion. Heat is applied.
As a result, in the manufactured magnetic tape cassette, as described above, the projection 306a of the temporarily joined portion is deformed and crushed by the action of ultrasonic waves or heat, and the window member 306 is opened in the upper half 300. It can be securely fixed in the groove 300c between the upper and lower window frames 300b and 300d of 300a. Of course, when disassembling from the upper half 300 of the window member 306, it is needless to say that as described above, it can be completely disassembled and separated easily and safely without fixing a part thereof. . This method of manufacturing a magnetic tape cassette is a very effective method.

Next, a magnetic tape cassette and a method for manufacturing the magnetic tape cassette according to the ninth related technique of the present invention will be described with reference to FIGS.
The magnetic tape cassette according to the related technology also has the same configuration as the magnetic tape cassette shown in FIG. 1 except for the structure of the upper half transparent window and its mounting structure. Only the structure will be described in detail, and the other description will be omitted.
43 is a longitudinal sectional perspective view showing an upper half of one configuration example of the magnetic tape cassette according to the related art, and FIG. 44 is a partially enlarged sectional view of the upper half shown in FIG. In the present configuration example, as is clear from these drawings, the transparent window includes an opening 330a formed in the upper half 330 and a window member 336 made of a transparent resin attached to the opening 330a. It has become.

  As shown in FIG. 44, the opening 330a formed in the main body of the upper half 330 is provided with recesses 330b and 330c on both side surfaces of the opening 330a, and an edge 330d is formed on the inside thereof. It has a cross-sectional shape. Here, in the configuration example shown in FIG. 44, the cross-sectional shape of the edge portion 330d formed inside the opening portion 330a is a shape in which a quadrangular block protrudes. The shape is not limited to a quadrangular shape.

  The edge 330d provided inside the opening 330a may be provided on the entire circumference along the inside of the opening 330a, or may be provided intermittently. However, it is desirable to provide the edge 330d shown in FIG.

Next, a method for forming the transparent window will be described.
45 (a) and 45 (b) are diagrams for explaining a method for manufacturing the transparent window according to the configuration example shown in FIG. 44, in which the upper half body 330 having the transparent window according to the related technology is molded and molded. The forming mold includes an upper mold 360 and a lower mold 362 that mold the entire shape of the upper half body 330. The upper mold 360 and the lower mold 362 for molding the entire shape of the upper half main body 330 are well-known ones for molding the upper half main body 330 into a predetermined shape, and are the same as those in the prior art. Will be omitted, and only the parts related to the method of manufacturing the transparent window will be described.

  The first core (or the upper core 360, which forms the opening 330a for mounting the transparent window, is formed in the upper die 360 and forms the concave portion 330b on the surface side of the molding die composed of the upper die 360 and the lower die 362. Cavities) 364 and a second core 366 (or cavity) that is provided in the lower mold 362 and forms a recess 330c on the back surface side and an edge 330d of the opening 330a. Both the 364 and the second core 366 are configured to be able to be inserted into and removed from the upper mold 360 or the lower mold 362.

  When the upper half body 330 is molded with this mold, the first core 364 and the second core 366 are projected from the upper mold 360 or the lower mold 362 as shown in FIG. By bringing the tips of the core 364 and the second core 366 into close contact with each other, the space formed by the upper mold 360 and the lower mold 362 and the first core 364 and the second core 366, that is, the cavity 368, A resin such as ABS resin is injected and injection molded to mold the upper half main body 330, and the concave portions 330b and 330c on both side surfaces formed in the opening 330a and the edge portion 330d formed inside thereof are molded. .

Next, when the transparent window member 336 is formed in the opening 330a of the upper half main body 330, the above-described upper mold 360 and lower mold 362, and the first core 364 and the second core 366 are combined. Using the mold as it is, as shown in FIG. 45 (b), the molded upper half body 330, the first core 364, and the second core 366 are immersed in the upper mold 360 and the lower mold 362. A transparent resin that is incompatible with or extremely incompatible with a resin such as ABS resin injected to mold the upper half body 330 into the space formed by the mold, that is, the cavity 370. For example, PS resin is injected, and a transparent window member 336 is integrally molded and attached to the upper half main body 330.
The transparent window according to the configuration example shown in FIG. 46 can also be formed in the same manner by injecting a transparent resin into the cavity (372), and therefore detailed description thereof is omitted here.

  By the way, the manufacturing method of the magnetic tape cassette which concerns on this related technique which manufactures the magnetic tape cassette which concerns on the said structural example consists of the upper mold | type 360 and the lower mold 362 as a shaping | molding die for shape | molding the upper half main body 330, Furthermore, First core 364 slidable from the front side of upper half body 330 to form opening 330a of upper half body 330, and slidable from the back side of upper half body 330, and opening of upper half body 330 First, a first mold of the molding die is used. The molding die includes a second core 366 having concave portions 366a and 366a at both ends for providing a convex portion 330d for locking the window member 336 to the 330a. The core 364 and the second core 366 are brought into close contact with each other, and the upper half main body forming resin material is injected, and the upper half main body 330 having the opening 330a. After the molding, the first core 364 and the second core 366 of the mold are separated from each other, and the space (cavity) formed therebetween is not compatible with the upper half body forming resin material. Alternatively, a transparent window member forming resin material having extremely low compatibility is injected to mold the window member 336, and the upper half main body 330 and the window member 336 are integrally molded. This method of manufacturing a magnetic tape cassette is a very effective method.

  When the magnetic tape cassette employing the upper half body 330 is disassembled and separated in order to recycle a cassette case discarded after use, the upper half 330 is removed and the window member 336 is moved from the lower side in the figure. It can be easily disassembled by pressing strongly. That is, in the first configuration example shown in FIG. 44, since the upper half main body 330 and the window member 336 are not welded, the edge 330d of the opening 330a is plasticized by strongly pressing the window member 336 from the lower side. It can be easily disassembled by being deformed or by cracking and dropping off the edge portion of the window member 336.

  In particular, the stress is concentrated by placing the lower end of the edge portion 330d of the upper half body 330 close to the upper end of the annular portion 336a of the window member 336, and forming both ends into a pointed shape, and a relatively small force. Thus, the annular portion 336a of the window member 336 can be configured to crack and fall off. In this case, it is desirable to provide the edge 330d along the entire inner side of the opening 330a so as to crack and fall off along the entire periphery of the opening 330a.

  The window member formed by the configuration example shown in FIG. 46 is configured such that the edge 330e of the opening 330a is more easily deformed by strongly pressing the window member 336 from below. In this configuration example, since the cross-sectional shape of the edge portion 330e is a shape in which a triangular block whose inner side is inclined protrudes, the inclined surface is elastically deformed by pressing the window member 336 from below, Further, the window member 336 can be easily disassembled from the upper half main body 330 by causing plastic deformation by pressing more strongly and the annular portion 336a of the window member 336 falling off. Therefore, in the case of this related technology, it is desirable to provide the edge 330e intermittently along the inside of the opening 330a.

  The transparent window used in the magnetic tape cassette according to this configuration example is configured as described above, and the upper half 330 serving as the base and the window member 336 are not compatible with each other (or compatible resin). Since it is molded as a single piece with a resin that is rare, it has excellent airtightness for dust prevention, etc., and it is mainly external even when being handled by hand such as carrying, storing, loading into a recording / reproducing device, etc. Therefore, if the strength of the edge portion 330d or 330e is secured so as not to be broken or detached due to the impact from the inside, there is no problem in terms of strength.

Although described later, a magnetic tape cassette according to an embodiment of the present invention and a method of forming the magnetic tape cassette by a two-color molding method will be described below with reference to FIGS.
In particular, in the examples used in the following description, a magnetic tape cassette is taken as a representative example as a resin product, and in particular, an upper half constituting a casing of the magnetic tape cassette and a magnetic tape provided on the upper half are particularly mentioned. Although described as a method for forming a transparent window for confirmation, the present invention is not limited to this. The magnetic tape cassette of the present embodiment also has the same configuration as that of the magnetic tape cassette shown in FIG. 1 except for the structure of the upper half transparent window and its mounting structure. Only the structure will be described in detail, and the other description will be omitted.

  FIG. 47 is a plan view showing the upper half of the magnetic tape cassette according to the present embodiment and the transparent window for checking the magnetic tape provided in the upper half. As shown in FIG. 47, the upper half 410 is provided with a transparent window (hereinafter simply referred to as a window) 412 for confirming the remaining amount of the magnetic tape stored in the housing. The window 412 has protrusions 412a, 412b,... Around the window 412, and is fitted to a predetermined shape provided on the upper half 410 side. This state is shown in FIG. 48 as a cross-sectional view along the line VIII-VIII. As shown in FIG. 48, the protrusions 412 a and 412 b of the window 412 are vertically fitted alternately with a predetermined shape provided at the end 411 of the opening of the window portion of the upper half 410.

  In FIG. 49, the combination state of the upper half 410 and the window 412 is further easily understood, and a part thereof is enlarged and shown in a perspective view. As shown in FIG. 49, the projection 412a of the window 412 is fitted into a recess 411a provided at the end 411 of the window opening of the upper half 410, and the projection 412b is the end of the window opening of the upper half 410. It is fitted into the recess 411 b of the part 411. Here, the recess 411a has a bottom surface, and the protrusion 412a is on the bottom surface, and the upper part is open. Moreover, the recessed part 411b does not have a bottom face, and instead, the upper part is closed like a lid, and a protrusion 412b is fitted therein.

In this embodiment, the upper half 410 and the window 412 are simultaneously formed by core back type two-color molding, and the window 412 can be assembled from the upper half 410 so as to be easily disassembled. It is.
For this purpose, the upper half 410 is configured such that the end 411 of the window opening has a shape as shown in FIG. That is, the recesses 411a to 411d into which the protrusions 412a and the like of the window 412 are fitted, and the recesses 411a ′ to 411d ′ for forming these protrusions 412a and the like are formed along the end 411 of the window opening.

At this time, the recesses 411a and the like into which the protrusions 412a and the like of the window 412 are fitted are adjacent to each other so that the window 412 and the upper half 410 are up and down. That is, the recess 411a has a bottom surface 413, but the recess 411c does not have a bottom surface 413, but instead has a top surface 415 like a lid.
The bottom surface 413 is formed so as to protrude slightly inward from the window opening along the end 411 of the window opening. This is because, as will be described later, when the window 412 is assembled, the edge of the window 412 slightly rides on the bottom surface 413 to completely eliminate the gap and improve the dust resistance.

  FIG. 51 shows a part of the window 412 as an enlarged perspective view. As shown in FIG. 51, the window 412 has protrusions 412 a to 412 d for coupling to the upper half 410. The protrusions 412a and the like are formed with the same thickness as the window 412. The protrusions 412a and the like are rounded at the corners so that the protrusions 412a and the like can be easily fitted with the recesses 411a and the like of the upper half 410. Or you may make it provide a predetermined taper in order to make it fit with the recessed part 411a of the upper half 410, etc. reliably.

  FIG. 52 is a partially enlarged perspective view showing a state where the upper half 410 and the window 412 are formed at the same time. In this embodiment, the upper half 410 and the window 412 are formed of materials that are not compatible with each other and are not adhesive to each other at the same time, and then the window 412 is removed and turned upside down. To fit in. Therefore, as shown in FIG. 52, for example, in order to mold the protrusion 412a of the window 412, a recess 411a 'is provided on the opposite side of the recess 411a across the window opening of the upper half 410. Similarly, a recess 411b 'is provided on the opposite side of the recess 411b of the upper half 410 to mold the projection 412b, and a recess 411c' is provided on the opposite side of the recess 411c of the upper half 410 to mold the projection 412c. It has been. A recess 411d 'for forming the protrusion 412d is provided next to the recess 411d.

  FIG. 53 shows a configuration example of a mold for forming the upper half 410 and the window 412 as shown in FIG. 53A and 53B are cross-sectional views of the mold corresponding to the cross section taken along line IX-IX in FIG. As shown in FIG. 53A, a mold 420 for forming the upper half 410 and the window 412 is mainly composed of an upper mold 422, a lower mold 424, and a movable core 426. First, molten resin is injected into a space (cavity) 430 formed by the upper mold 422, the lower mold 424 and the movable core 426 to mold the upper half 410.

Next, as shown in FIG. 53 (b), the movable core 426 is moved downward by the thickness of the window 412, and the resulting space 432 is bonded to each other and is not compatible with the resin in which the upper half is molded. The window 412 is formed by injecting resin having no property.
An outline of the movable core 426 is shown in a perspective view in FIG. The movable core 426 has a protrusion 426a and the like for forming the protrusion 412a and the like of the window 412. Note that the movable core 426 shown in FIGS. 53A and 53B shows a cross section taken along the line HH in FIG. 53C.

  Thus, by forming two colors with the same mold 420, the upper half 410 and the window 412 are molded as shown in FIG. 52 at the same timing. As described above, since the upper half 410 and the window 412 are made of incompatible materials, the window 412 is lifted from the upper half 410 after molding (in FIG. 52, the window 412 is lifted upward). ) Easy to remove.

  The removed window 412 is turned over and fitted into the upper half 410 as shown in FIG. That is, the projection 412 a of the window formed by the recess 411 a ′ of the upper half 410 is fitted into the recess 411 a of the upper half 410. Similarly, the projection 412b of the window 412 formed by the recess 411b ′ is fitted into the recess 411b on the opposite side, and the projection 412c of the window 412 formed by the recess 411c ′ is fitted into the recess 411c on the opposite side. It is. Further, the projection 412d of the window 412 formed by the recess 411d 'is fitted into the recess 411d adjacent to the recess 411d'. In addition, the end of the window 412 is placed on the slightly overhanging bottom surface 413 of the upper half 410 so as to close the gap around the window 412 (in the portion where the protrusion 412a or the like is not provided) and to prevent dust. It is increasing.

  The magnetic tape cassette of the above embodiment is compatible with a resin part including the upper half (main body) 410 and the window (member) 412 by a manufacturing method to which the multicolor molding method of the resin product of this aspect is applied. In addition, using two or more kinds of materials that are not adhesive to each other, each part is molded in multiple colors with a single mold 20, and after molding, each part of the upper half 410 and the window member 412 is taken out, 412 can be manufactured by reversing the front and back and assembling the upper half 410.

  As described above, in the present embodiment, the upper half and the window are made of a material that is not compatible, that is, a material having a dissimilar value for the compatibilization parameter and a material that is not adhesive, and is the same in two-color molding. Molded with a mold, the window is separated from the upper half after molding, and the window is turned over so that it fits into the upper half, making it easy to assemble and later to separate and recover the window from the upper half To be able to.

In FIG. 52 or 54, for example, the fitting between the projection 412b of the window 412 and the recess 411b is drawn so that there is a gap between the upper portion of the projection 412b and the recess 411b. In order to express the coupling state of the protrusion 412b and the recess 411b in an easy-to-understand manner, in fact, as shown in the sectional view of FIG. 48 or the perspective view of FIG. Is closely fitted in the recess 411a of the upper half 410, and the window 412 does not rattle.
However, the connection between the window and the upper half is not limited to the above method, and the shape of the upper half and the window is not limited to this, and the window is locked to the upper half by other engagement methods. It may be.

  As described above, in this embodiment, the window and the upper half are formed of an incompatible material, and the window and the upper half are formed by core back type two-color molding (two-layer molding). By separating the window from the half and fitting it into the upper half by turning the window upside down, it is possible to lock the window to the upper half by the concave and convex fitting formed on the molded product or other engagements. It is possible to facilitate the separation and collection of each part.

Next, a magnetic tape cassette according to the tenth related technique of the present invention will be described with reference to FIGS.
The magnetic tape cassette according to the related technology also has the same configuration as the magnetic tape cassette shown in FIG. 1 except for the structure of the upper half transparent window and its mounting structure. Only the structure will be described in detail, and the other description will be omitted.
FIG. 55 is an enlarged perspective view showing a cross-section of a part of the operation locking portion provided in the upper half of the configuration example of the magnetic tape cassette according to the related technology, and FIG. 56 is a configuration shown in FIG. It is sectional drawing along the longitudinal direction of the magnetic tape cassette which concerns on an example. As is clear from FIGS. 55 and 56, the transparent window provided in the upper half 116 in this configuration example is provided with the opening 156a formed in the upper half body 156 over the entire length in the longitudinal direction of the upper half body 156. A window member 158 made of a transparent resin attached to the opening 156a is attached over the entire length of the upper half body 156 so as to cover the entire opening 156a.

  An edge 156b is provided on the inner side of the opening 156a of the upper half body 156, and the window 158a is provided on the edge 156b so that the edges 158a provided on both side surfaces of the window member 158 are placed. By attaching the member 158, the upper half main body 156 and the window member 158 are brought into close contact with each other to maintain the airtightness of the upper half 116, and are handled manually such as carrying, storing, and loading into a recording / reproducing apparatus. The window member 158 is configured not to be broken or detached due to an external pressing force or an impact caused by.

  Both ends of the window member 158 extend to both ends of an opening 156a provided in the longitudinal direction of the upper half main body 156, and a locking member 160 bent at a right angle is provided at the tip thereof. The operation locking claws 160a provided in the upper half main body 156 are fitted and locked in locking grooves 156c provided at both ends in the longitudinal direction. Further, a detaching groove 156d for inserting a tool when the operation locking claw 160a fitted and locked in the locking groove 156c is removed is provided below the locking groove 156c.

  Here, the window member 158 attached to the opening 156a of the upper half body 156 is preferably slightly curved upward so as to be in close contact with the opening 156a, and the locking member 160 of the window member 158 is used. It is desirable to keep the shape slightly warped inward. By adopting such a shape, the window member 158 comes into close contact with the edge portion 158a of the window member 158 and the edge portion 156b provided in the opening 156a of the upper half body 156 due to its own elasticity. The member 160 is biased so as to be surely fitted into the locking groove 156c and not to be removed.

  Since the magnetic tape cassette according to this configuration example is configured as described above, when the magnetic tape cassette is used, the magnetic tape cassette is provided at the edge 156b provided at the opening 156a of the upper half body 156 and the window member 158. Since the edge 158a is attached in close contact, there is no practical problem with respect to airtightness and strength. When the magnetic tape cassette is discarded after use, a tool is inserted into the removal groove 156d of the upper half main body 156, and the operation locking claw 160a of the locking member 160 provided in the window member 158 is inserted into the locking groove 156c. It can be easily disassembled by removing it by extruding it, and other materials do not adhere to the disassembled upper half body 156 and window member 158.

  In the configuration example shown in FIGS. 55 and 56, the removal groove 156d provided in the upper half body 156 is sufficient to insert a tool for releasing the locking of the operation locking claw 160a. However, it is needless to say that the shape may be continuous from the upper end to the lower end of the upper half end face.

  57 is a perspective view of a magnetic tape cassette having a transparent window according to another configuration example of the related technology, and FIG. 58 is a cross-sectional view taken along the line AA in FIG. In this configuration example, the window member 158 is not provided over the entire length of the upper half main body 156 in the longitudinal direction, and a transparent window having the same size as that of the prior art can be obtained. That is, the transparent window of the upper half 116 in this configuration example is provided with an opening 156a having the same size as that of the prior art in the upper half body 156 as shown in FIG. 57, and the opening 156a has the same size as this. The window member 158 is fitted.

  On the inner side of the opening 156a of the upper half body 156, an edge 156b similar to the above configuration example is provided over the entire circumference except for the notch 156e of the opening 156a, and the above configuration example is provided on this edge 156b. The edge part 158a of the window member 158 similar to is mounted and mounted. As shown in FIG. 58 (a) or (b), the side of one of the window members 158 (the left side in FIG. 58) is sandwiched so as to sandwich the edge 156b of the upper half body 156. A claw 158b is provided, and the clamping claw 158b clamps the edge 156b of the upper half main body 156 and the edge 158a of the window member 158 in close contact with each other.

  A locking member 162 that fixes the window member 158 to the upper half main body 156 is provided at the center of the other side surface (the right side in FIG. 58) of the window member 158. Note that the locking member 162 in this configuration example is located in the notch 156e of the opening 156a of the upper half body 156 described above, and the locking claw 162a on the window member 158 side on the lower surface of the upper half body 156. The spring portion 162b, which is thin and elastic, can be securely locked to the lower surface of the upper half body 156.

  In the configuration example shown in FIG. 58 (a), the clamping claw 158b of the window member 158 and the locking claw 162a of the locking member 162 protrude below the upper half main body 156. When it is not desirable that the clamping claws 158b and the locking claws 162a protrude below the upper half main body 156 due to the arrangement of the tape or the like, as shown in FIG. 58 (b), the clamping claws 158b of the window member 158 And the locking claw 162a of the locking member 162 can be disposed inside the upper half body 156. In this case, the recess for locking the locking claw 162a can be used as it is as the removal groove 156f for removing the locking claw 162a from the lower surface of the upper half.

  In the magnetic tape cassette shown in this configuration example, when the magnetic tape cassette is used, the edge 156b provided in the opening 156a of the upper half body 156 and the edge 158a provided in the window member 158 are in close contact with each other. Therefore, there is no practical problem with respect to the airtightness and strength of the window member 158.

  In both the configuration examples shown in FIGS. 58A and 58B, when the magnetic tape cassette is discarded after use, a tool is inserted into the operation locking portion 156g or 156h from the upper surface of the cassette case. Thus, the cassette case can be easily disassembled by removing the latching claws 162a of the latching member 162 from the notches of the corresponding openings 156a without disassembling the upper half main body 156. Other materials are not fixed to and mixed in the upper half main body 156 and the window member 158.

In addition, this related technology is not limited to the above-described configuration example, and it is also possible to adopt a locking claw having another structure, for visually confirming the inside provided in another type of magnetic tape cassette. Obviously, the same applies to various transparent windows.
For example, in each of the above configuration examples, the example in which the window member 158 is mechanically locked to the upper half 156 is shown. However, the related technology is not limited to this, and the window member 158 is fixed to the upper half. It can also be used in a state where it is locked by heat welding to 156 or a state where it is locked by heat melting with compatible resins.

Next, a magnetic tape cassette according to the eleventh related art of the present invention will be described.
By the way, as described above, conventionally, when selecting the type of resin that constitutes each part (member) of the magnetic tape cassette, its mechanical strength (including creep resistance), dimensional stability, In recent years, physical properties such as heat resistance or chemical properties such as corrosion resistance have been regarded as important. Easiness (hereinafter referred to as biodegradability) has been considered.

A magnetic tape cassette (hereinafter simply referred to as a cassette) according to the related art uses such a resin having excellent biodegradability as a resin constituting each part (member) of the cassette. In the description of the related art, “upper” means the side where the upper half is located, and “lower” means the side where the lower half is located.
This related technology is applied to a magnetic tape cassette having a magnetic tape and a casing for rotatably storing the magnetic tape, and a pair of tape reels formed by winding the magnetic tape around a pair of reel hubs is provided in the casing. The present invention is also applicable to any two-reel type magnetic tape cassette that is accommodated in a predetermined location so that the magnetic tape can be pulled out or run from. Alternatively, any one reel type of magnetic material in which a single tape reel formed by winding a magnetic tape around one reel hub is accommodated in a predetermined location so that the magnetic tape can be pulled out or run from the housing. The present invention can also be applied to a tape cassette.

  Further, in the cassette of the related technology, the casing (cassette case) means that the upper half and the lower half are main constituent members, and the magnetic tape is wound including other members attached to the upper half or the lower half. This means a member including a tape reel and a member attached to the upper half or the lower half in order to hold or accommodate a part of the magnetic tape drawn out from the tape reel. For example, as other members, it is composed of a plurality of members including a lid (front lid), a slider that is slidably mounted on the bottom surface of the lower half, and is formed by combining the upper half and the lower half Say.

  In the cassette of one configuration example of the related art, the window member fitted in at least one of the window openings provided in the upper half is made of a biodegradable resin. The biodegradable resin that forms the window member, while maintaining the same functions as conventional resins during use, is finally decomposed into inorganic substances such as water and carbon dioxide by the action of microorganisms that exist in nature after use. This resin is a biodegradable resin whose test method is described in ISO14851, ISO14852, or ISO14855.

  Here, in ISO14851 and ISO14852, biodegradability in an aerobic water system is prescribed, in ISO14885, the decomposition rate is obtained from oxygen consumption, and in ISO14852, the decomposition rate is obtained from the amount of generated carbon dioxide. The one that reaches the decomposition rate. ISO 14855 refers to a substance that decomposes 70% or more in a maximum of 6 months from the amount of carbon dioxide generated under composting conditions.

The biodegradable resins are broadly classified as follows.
(1) Microbial production polymer (a) Poly β-hydroxybutyric acid (for example, Bio Green, manufactured by Mitsubishi Gas Chemical)
(B) Polyhydroxybutyrate / valerate (for example, Biopol made by Nippon Monsanto, but up to about 30% as an additive (filler))

(2) Synthetic polymer (a) Polylactic acid (for example, Lacty manufactured by Shimadzu Corporation, Lacia manufactured by Mitsui Chemicals, Eco-Play manufactured by Cargill Dow)
(B) Polycaprolactone (PCL) (for example, Sercelin PH manufactured by Daicel Chemical Industries, but up to about 30% as an additive (filler))

(3) Natural product polymer (a) Cellulose acetate (for example, Cell Green P- manufactured by Daicel Chemical Industries)
CA,)
(B) Starch + PCL (for example, Matterby made by Nippon Synthetic Chemical, Novon made by Chisso)
(C) Modified starch (for example, corn starch manufactured by Nippon Corn Starch)
However, any of the above polymers can be used as an additive (filler).

  In this embodiment, a microbial degradation accelerator may be used. Examples of the microbial degradation accelerator include corn starch, potato starch, rice starch, and master batches obtained by blending various starches such as these modified starches at a high concentration.

  Here, as the biodegradable resin for forming the window member, a material mainly composed of polylactic acid is preferable. Furthermore, polylactic acid may be polyhydroxybutylene (PHB), polycaprolactone (PCL), or polybutylene succinate (PBS). ) Is preferred. In particular, polylactic acid blended with polyhydroxybutylene (PHB), polycaprolactone (PCL) or polybutylene succinate (PBS) in an amount of 1 to 60%, and further 20 to 30% is excellent in melt fluidity during molding. And it is preferable at the point which can obtain the window member excellent in impact resistance, transparency, and hydrolysis resistance obtained.

  In this configuration example, the window member made of a biodegradable resin can be molded by injection molding using the biodegradable resin or a material containing the biodegradable resin as a main material and other components. . Further, the shape, dimensions, etc. are appropriately selected according to the magnetic tape cassette to be fitted.

  In addition, the method of fitting the window member into the window opening can be performed by various methods such as welding, mechanical fitting, and snap fitting, and is not particularly limited. In addition, when fitting by welding, for example, compared with the case where the half is made of a general-purpose resin such as ABS, in the biodegradable resin, the amount of heat generated when used for thermal recycling is the conventional ABS. Less than half.

Next, with reference to FIGS. 59 to 64, a method for destructive separation of dissimilar materials according to the twelfth related art of the present invention will be described.
The following is a method for destructing and separating different materials according to the related art. As a resin product made of different materials, a magnetic tape cassette is taken as a representative example, and a residual amount of magnetic tape provided in a cassette case (housing) is confirmed. It goes without saying that the present invention, which will be described in detail, is not limited to the method for making it possible to easily separate and recover the transparent window by breaking it from the casing.

  FIG. 59 shows a magnetic tape cassette according to this configuration example. As shown in FIG. 59, the magnetic tape cassette 460 according to this configuration example includes an upper half 461 and a lower half 462 constituting a casing (cassette case). A slider 463 is attached to the lower surface side of the lower half 462, and a lid 464 is provided on the front side of the cassette (front side in the figure). The slider 463 is installed so as to be slidable in the front-rear direction of the cassette along the lower surface of the lower half 462. When the cassette is not used, the open portion on the lower side of the cassette case is closed to prevent dust. The lid 464 is attached to the upper half 461 so as to be rotatable around a support shaft 464a so that the front side of the cassette can be opened and closed. Also in this configuration example, the configuration of the magnetic tape cassette not shown in FIG. 59 is the same as that of the magnetic tape cassette shown in FIG. 1, and therefore, detailed description thereof will be omitted below.

In addition, a magnetic tape (not shown) wound around a pair of winding hubs is accommodated in the housing of the magnetic tape cassette 460. The upper half 461 is provided with a transparent window 466 for checking the remaining amount of tape when the magnetic tape cassette 460 is taken out from a deck (not shown) during use, for example.
In this configuration example, the window 466 can be easily separated and recovered from the upper half 461 constituting the magnetic tape cassette housing.

  Therefore, the window 466 of the magnetic tape cassette 460 of this configuration example is devised so that it can be easily broken and separated. That is, normally, when the window 466 is injection-molded, molten resin is injected and molded from the gate provided at the center of the window 466. In this configuration example, as shown in FIG. 466 is provided at one end in the longitudinal direction. A destruction mark 468 is provided at the other end of the window 466 facing the gate 467 in the longitudinal direction. Here, the destruction mark 468 can be easily broken if a force is applied to the position of the destruction mark 468 when the window 466 is separated and recovered from the upper half 461, and the window 466 is divided into the upper half 461. It is a sign indicating that it can be easily separated from.

  In general, it is known that an injection molded product tends to be easily broken in the flow direction of the molten resin. In addition, if the thickness is the same, the molten resin has a property of trying to flow uniformly and radially from the gate. For example, when the window 466 of the magnetic tape cassette shown in FIG. 59 is injection-molded, the molten resin is radially spread from the gate 467 and molded as shown in FIG. Therefore, when a force is applied to an arbitrary point P to generate a crack 469, the crack 469 proceeds toward the gate 467 perpendicular to the radial line where the resin spreads.

  In this configuration example, by utilizing this property, as shown in FIG. 59 or FIG. 61, in the longitudinal direction of the window 466, a destruction mark 468 is attached at a position facing the gate 467 opposite to the gate 467. . In this configuration example, the gate 467 is at the midpoint (slightly inside) of one side in the longitudinal direction of the window 466, and the destruction mark 468 is opposed to the opposite side of the side in the longitudinal direction of the window 466. It is arranged at the midpoint (slightly inside). If a force is applied to the breakage mark 468, the window 466 can be cleanly divided into two in the longitudinal direction from the breakage mark 468 to the gate 467 straight.

The method of attaching the breakage mark 468 described above is not particularly limited, and when the window 466 is injection-molded, it may be molded by a mold so as to have a predetermined shape such as a triangle (Δ) or later. A stamp may be pressed, a predetermined mark or a character indicating that the mark can be clearly broken if pressed, or such a sticker may be affixed.
Note that the window 466 may be molded by two-color molding simultaneously with the same mold as the upper half 461, or the window 466 may be molded separately.

Further, two short sides (end portions) 466a and 466b of the window 466 that intersect with a straight line connecting the gate 467 and the destruction mark 468 are not fixed to the upper half 461, and are a straight line connecting the gate 467 and the destruction mark 468. If only the other two long sides 466c and 466d of the window 466 that do not intersect with each other are fixed to the upper half 461, the window 466 can be broken in the longitudinal direction cleanly in the middle.
The fixing method of the sides 466c and 466d in the longitudinal direction of the window 466 is not to fix the entire side, but as shown in FIG. 62, several protrusions 20 are provided on the sides 466c and 466d, and only here. The upper half 461 may be bonded. In this way, after the window 466 is broken into two in the longitudinal direction, each part is fixed to the upper half 461 only in several places, so that each part after the break is separated from the upper half 461. Is easy.

  In addition, if the fracture mark 468 is broken only by applying a very small force, the strength of the product cannot be secured during normal use. Therefore, a certain amount of force must be applied to the fracture mark 468 when actually breaking. It is also necessary to prevent cracks from occurring. However, it takes a considerable amount of force to break and it becomes difficult to break. Therefore, as shown in FIG. 63, a slight notch 472 is made in the side 466b on the side where the destruction mark 468 is present, and a force is applied to the destruction mark 468 so as to apply a force in the direction toward the gate 467. In this case, the crack may smoothly enter from the destruction mark 468 toward the gate 467.

  In this way, if a force is applied to the breakage mark 468 in the direction along the notch 472, a crack extends from the notch 472 toward the gate 467 without applying a great force, so that the window can be easily displayed. 466 can be broken. The notch 472 may be provided so that the side 466b of the window 466 slightly overlaps the upper half 461, and is provided at the overlapping portion. In this way, dust does not enter the magnetic tape cassette through the gap of the notch 472.

  Further, as shown in FIG. 64, a linear groove 474 that connects the gate 467 and the destruction mark 468 may be provided in the longitudinal direction of the window 466. If the groove 474 is too deep, the groove 474 may be broken by a slight impact in normal use. Further, when the window 466 is to be broken by applying a force to the break mark 468, the crack is broken by the gate 467. It doesn't have to be so deep because it only has to help you move forward.

  By the way, depending on the window of the magnetic tape cassette, there is a case where a rib for regulating the position of the take-up hub of the magnetic tape is installed inside the window. In such a window, force is applied to the destruction mark. However, the cracks entered from the destruction mark may stop at the take-up hub position regulating rib, or the direction may change from side to side, and the window may not break well in the longitudinal direction.

Even in such a case, if a groove 474 as shown in FIG. 64 is inserted, cracks will advance along the groove 474, and the window can be reliably broken in the longitudinal direction.
Alternatively, the winding hub position regulating rib may be cut out at a portion corresponding to a position where the crack advances from the break mark toward the gate.

  Normally, in window injection molding, the gate is located at the center of the window, but in this case as well, a break mark is placed near the middle of one side in the longitudinal direction of the window as in the above configuration example. If you push the destruction mark, the crack will progress toward the center gate. If cracked properly, the crack advances directly beyond the central gate toward the opposite side in the longitudinal direction. Therefore, even in this case, the method of attaching the fracture mark in this configuration example is effective.

In addition to the rectangular windows shown above, various shapes are conceivable, but even in that case, the position where the destruction mark is applied is a crack from that point to the gate by applying an impact to that point. It is good to set it in a position where it enters. For example, a destructive mark may be put on a position farthest from the gate on the window.
Considering the relative positions of the gate and the destruction mark, the gate and the destruction mark are generally provided at positions where the straight line connecting the gate and the destruction mark has the longest length that cuts the window. Then, the window can be largely broken by approximately half, and the subsequent separation and recovery can be facilitated, which is preferable.

As described above, one configuration example of the related art has been described in detail. According to this configuration example, the transparent window for checking the remaining amount of the magnetic tape provided in the upper half of the magnetic tape cassette can be easily broken to Separation of the window from the half can be performed smoothly, reliably and safely.
Moreover, this related technology is applicable not only to the window of such a magnetic tape cassette but also to other resin molded products in general.

As mentioned above, regarding the magnetic tape cassette according to the present invention and the manufacturing method related thereto, resin molded products, multicolor molding methods of resin products, and fracture separation methods of different materials, various examples and configuration examples of related technologies are given. However, the above embodiments and configuration examples are only examples, and the idea of the present invention can be easily changed in detail, and other types of magnetic tape cassettes. Obviously, the present invention can be similarly applied, and various improvements and modifications can be made without departing from the spirit of the present invention.
For example, the disassembleable transparent window as described above is provided not only for checking the remaining amount of the tape of the magnetic tape cassette but also for visually checking the inside, in particular, various types provided for other types of magnetic tape cassettes. It is obvious that the present invention can be similarly applied to the transparent windows and the like, and the assembly of various transparent windows.
Further, the various joining methods of different resin (plastic) parts according to the present invention shown in the above embodiments and configuration examples can be widely applied to resin (plastic) products other than magnetic tape cassettes.

It is a disassembled perspective view of one structural example of the magnetic tape cassette which concerns on one related technique of this invention. It is the perspective view which made the cross section the transparent window part of the upper half of the magnetic tape cassette shown in FIG. 1 by the arrow II line. It is a fragmentary sectional view of the upper half shown in FIG. (A) is a partial expanded sectional view which shows the state of engagement with the wedge-shaped protrusion of the upper half main body shown in FIG. 3, and the wedge-shaped protrusion of a window member, (b) shows the modification. It is a partial expanded sectional view. It is sectional drawing of the upper half of the other structural example of the magnetic tape cassette which concerns on one related technology of this invention. (A) is an expanded sectional view which shows the state of engagement with the window frame of the upper half main body shown in FIG. 5, and the nail | claw member of a window member, (b) is an expanded sectional view which shows the modification. . It is sectional drawing of the upper half of the other structural example of the magnetic tape cassette which concerns on one related technology of this invention. It is a perspective view of the window member in the structural example shown in FIG. It is the elements on larger scale of the window member latching | locking part provided in the upper half of the other structural example of the magnetic tape cassette which concerns on one related technology of this invention. FIG. 10 is a perspective view of a window member having a locking member that is locked to the upper half window member locking portion shown in FIG. 9. It is sectional drawing in the virtual centerline II-II in FIG. 9 of the window member latching | locking part provided in the window member and the upper half. (A)-(c) is a schematic diagram explaining the condition which inserts the window member which concerns on one related technique of this invention in the window member latching | locking part provided in the upper half, respectively. (A)-(c) is a schematic diagram explaining the condition which removes the window member which concerns on one related technique of this invention from the window member latching | locking part provided in the upper half, respectively. (A)-(d) is the perspective view which enumerated the structural example of the shape of the latching member provided in the side surface of the window member which respectively concerns on one related technique of this invention. It is sectional drawing which shows the further detail of the latching groove | channel of the window member latching | locking part which concerns on the structural example shown in FIG. (A) And (b) is detail sectional drawing (the 1) which shows another example of a structure of the latching groove | channel of the window member latching | locking part provided in the upper half main body which concerns on one related technique of this invention, respectively. is there. It is detail sectional drawing (the 2) which shows another structural example of the latching groove | channel of the window member latching | locking part provided in the upper half main body which concerns on one related technique of this invention. It is sectional drawing of the transparent window part of the upper half which shows one structural example of the other related technology of this invention. It is sectional drawing in the surface orthogonal to FIG. 18 of the transparent window part of the upper half of this structural example. It is a perspective view which shows the detail of the part which fits the transparent window of the upper half based on the other structural example of this related art. It is a perspective view which shows the outline of one structural example of the magnetic tape cassette which concerns on the other related technology of this invention. It is sectional drawing along the III-III line of FIG. It is sectional drawing along the IV-IV line of FIG. It is a perspective view which expands and shows a part of window receiving part of the upper half of the magnetic tape cassette of this structural example. It is a perspective view which shows the state which integrated the window in FIG. It is a perspective view which shows the window in this structural example. It is a perspective view of the magnetic tape cassette which shows the assembly method of the window in this structural example. It is a perspective view which shows the other example of the window in this structural example. It is a perspective view of the upper half of one structural example of the magnetic tape cassette which has the transparent window which concerns on the other related technology of this invention. It is the VV sectional view taken on the line which shows the part of the transparent window of the upper half shown in FIG. It is a side view which shows the window member shown in FIG. It is the perspective view which looked at the window member shown in FIG. 31 from the downward direction. It is a figure which shows the part of the transparent window of the other structural example of the magnetic tape cassette which concerns on this related technique, (a) is a perspective view, (b) is a side view. It is a perspective view which shows the opening part of the upper half in the structural example shown in FIG. It is a figure explaining the engagement condition of the window member and opening part internal peripheral surface in the structural example shown in FIG. It is a perspective view of an example of 1 composition of a magnetic tape cassette which has a disassembly transparent window concerning other related technology of the present invention. It is the VI-VI line sectional perspective view of the transparent window part of the upper half of the magnetic tape cassette in FIG. It is the VII-VII sectional view taken on the line of the upper half in FIG. It is the VII-VII sectional view taken on the line of the window member of the transparent window in FIG. It is sectional drawing when the window member shown in FIG. 39 is inserted in the groove part of an upper half, and is temporarily joined. It is sectional drawing of the junction part which fixed the temporary junction part shown in FIG. 40 by ultrasonic welding or heat welding. It is the perspective view which made the cross section the part of the transparent window of the upper half of the other structural example of the magnetic tape cassette which concerns on this related art. It is a fractured perspective view which shows the upper half of the example of 1 structure of the magnetic tape cassette which concerns on the other related technology of this invention. It is sectional drawing of the transparent window part of the upper half shown in FIG. (A) And (b) is sectional drawing which shows the state of the shaping | molding die for demonstrating an example of the manufacturing method of the transparent window of the upper half shown in FIG. 44, respectively. It is sectional drawing of the window part of the upper half of the other structural example of the magnetic tape cassette which concerns on this related technique, and its shaping | molding die. It is a top view which shows the window for magnetic tape confirmation provided in the upper half of one Example of the magnetic tape cassette which concerns on one Embodiment of this invention, and this upper half. It is sectional drawing along the VIII-VIII line of FIG. 47 which shows the combined state of an upper half and a window. It is a perspective view which expands and shows the combination state of the upper half and window shown in FIG. It is a perspective view which expands and shows a part of upper half which concerns on this embodiment. It is a perspective view which expands and shows a part of window concerning this embodiment. It is an expansion perspective view which shows a mode when the upper half and window which concern on this embodiment are shape | molded simultaneously. (A) And (b) is sectional drawing of the metal mold | die corresponding to the cross section along the IX-IX line of FIG. 52, respectively, (c) is a perspective view which shows a movable core. It is an expansion perspective view which shows the state which assembled | attached the window which concerns on this embodiment to the upper half after shaping | molding. It is the expansion perspective view made into the partial cross section of the latching | locking part for operation provided in the upper half of the one structural example of the magnetic tape cassette which concerns on the other related technology of this invention. It is sectional drawing along the longitudinal direction of the upper half shown in FIG. It is a perspective view which shows the other structural example of the transparent window of the upper half of this related art. (A) And (b) is sectional drawing in the arrow XI-XI of FIG. 57, respectively. It is a perspective view which shows the outline of one structural example of the magnetic tape cassette which concerns on the other related technology of this invention. It is explanatory drawing which shows the destructive property of a general resin molded product. It is a perspective view which shows one structural example of the window of this related technology. It is a perspective view which shows the other structural example of the window of this related technology. It is a perspective view which shows the other structural example of the window of this related technology. It is a perspective view which shows the other structural example of the window of this related technology. It is a perspective view which shows the outline of a general magnetic tape cassette. (A) And (b) is a figure explaining the shaping | molding method of the upper half and window of the magnetic tape cassette performed conventionally. It is the perspective view which made the upper half of the prior art the cross section in the part of the transparent window. FIG. 68 is a cross-sectional view of the upper half including the transparent window portion shown in FIG. 67.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Magnetic tape cassette 16,116 Upper half 56,156,176,206 Upper half main body 56a, 156,206a Opening part 56b, 58a Wedge-like protrusion 56c Window frame 58,158,178,208 Window member 58b Locking claw 156b Edge portion 156c Locking groove 156d, 156f Removal groove 156e Notch portion 156g, 156h Operation locking portion 158a Edge portion 158b Holding claw 160, 162 Locking member 160a, 162a Operation locking claw 162b Spring portion 176a Locking groove 176aa Locking groove inlet side 176ab Locking groove outlet side 176ac Locking groove outlet side extension part 176b Stepped part 178a Locking member 178b Stepped part 206b, 206f, 206h Recessed part 206c, 206e Inclined surface 206d, 206g V-shaped projection 208a, 2 8g Flange 208b, 208d Inclined surface 208c, 208f V-shaped concave portion 210 Magnetic tape cassette 211, 250, 300, 330 Upper half 216 Window 216a, 216b (Window) concave portion 217 Window receiving portion 217a, 217b (Window receiving portion) ) End surface 218 (218a to 218d) Protruding part 256 Upper half main body 256a, 300a, 330a Opening part 258, 270 Window member 260 Screwed part 262 Engaging part 264 Gap 266, 276 Flange 272 Engaging protrusion 274 Engaging part 300b Upper part Window frame 300c Groove portion 300d Lower window frame 306 Transparent window 306a Protrusion 330b, 330c Recess 330d, 330e Edge portion 336 Window member 336a Annular portion 360 Upper die 362 Lower die 364 First core 366 Second core 368, 370, 372 Tie 410,461 Upper half 411 Upper half window opening end 411a to 411d, 411a 'to 411d' Recess 412 Window member 412a to 412d Protrusion 413 Bottom 415 Upper surface 420 Mold 422 Upper mold 424 Lower mold 426 Movable core 426a Protruding part 430, 432 Space 460 Magnetic tape cassette 466 Window 466a to 466d (Window) side 467 Gate 468 Destruction mark 469 Crack 470 Protruding part 472 Notch 474 Groove

Claims (1)

A magnetic tape cassette having a resin base having an opening for forming a transparent window and a transparent resin window member closing the opening of the base,
At least the base and the window member are two-color molded with a single mold using two kinds of resin materials that are not compatible with each other and are not adhesive to each other.
A magnetic tape cassette comprising the base after molding and the window member combined in a predetermined direction.

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