JP4017311B2 - Magnetic tape cassette - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic tape cassette, and more particularly to a magnetic tape cassette having an improved lid (front cover) provided in front of an upper half in order to protect a magnetic tape exposed on the front side of the cassette.
[0002]
[Prior art]
Conventionally, a small and light magnetic tape cassette capable of recording digital signals at high density has been used.
[0003]
This magnetic tape cassette, as defined by JIS X6127, X6129, X6130, or ECMA-288, is fixed to each end of a long magnetic tape and then wound with a pair of windings. Only the portion of the magnetic tape stretched between the pair of take-up hubs and the like on a case (cassette body) formed by joining the take-up hub or take-up reel with the upper half and the lower half joined together in a lid shape Is configured to be exposed.
In addition, since high-density recording is performed on the magnetic tape, it is necessary to improve the sealing of the case in order to prevent the fingers from coming into contact with the magnetic tape and the dust from adhering to the magnetic tape. Therefore, the upper half is provided with a front lid (lid) to cover the front side where the magnetic tape is exposed, and the lower half is provided with a slider that closes the opening on the lower side when the magnetic tape cassette is not used. It has been.
[0004]
FIG. 8 is a perspective exploded view showing a schematic configuration of a conventional magnetic tape cassette.
The magnetic tape cassette is coupled in a lid-like manner and is slidably mounted in the front-rear direction on the lower half of the upper half 110, the lower half 112, and the lower half 112 that constitute a casing that serves as a cassette case (cassette body). The slider 114 is mainly configured. In the case constituted by the upper half 110 and the lower half 112, the magnetic tape 132 wound around the winding hub 130 is accommodated. A front lid (lid) 120 that covers and protects the magnetic tape 132 when the cassette is not used is rotatably attached to the front side of the upper half 110. In addition, a slider 114 is attached to the lower surface of the lower half 112 so as to be slidable in the front-rear direction in order to block the open part on the lower side of the case and improve the sealing performance.
[0005]
A brake member 116 is attached to the upper half 110 in order to prevent the magnetic tape 132 wound around the winding hub 130 from loosening when the cassette is not used. The brake member 116 engages the brake piece 116 a with a gear 130 a provided on the upper portion of the winding hub 130, thereby prohibiting the rotation of the winding hub 130 and preventing the magnetic tape 132 from slackening. The brake member 116 is urged by a brake spring 118 to a position where the brake piece 116a is engaged with the gear 130a when the cassette is not used. The brake spring 118 is locked to a protrusion 110 a provided on the upper half 110.
[0006]
The lower half 112 has reel shaft insertion holes 112b and 112b for inserting the reel shaft into the cassette case when the cassette is used on the rectangular bottom surface 112a, and an overhang portion extending forward from the left and right ends of the bottom surface 112a. 112c and 112c. A cylindrical tape guide 112d for guiding the portion of the magnetic tape 132 stretched between the pair of winding hubs to be exposed to the front surface of the case when the cassette is used. , 112d are vertically provided on the bottom surface. The space between the left and right overhanging portions 112c and 112c is a space for a so-called tape loading device provided on the recording / reproducing device (deck) side into which the magnetic tape cassette is loaded to enter.
[0007]
The slider 114 is in contact with the bottom surface 112a of the lower half 112 from the lower side and slides in the front-rear direction of the cassette. When the slider 114 is positioned forward, the space between the left and right projecting portions 112c, 112c of the lower half 112 and The reel shaft insertion hole 112b is blocked by a bottom surface 114a of the slider 114 for dust prevention. Further, when the slider 114 is positioned rearward, the space between the left and right projecting portions 112c and 112c is opened, and the reel shaft insertion holes 114b and 114b provided on the bottom surface 114a of the slider 114 are provided in the lower half. 112 is aligned with the reel shaft insertion holes 112b and 112b. When the slider 114 is mounted on the deck when the cassette is used, the slider 114 is automatically positioned rearward due to the action of the device in the deck. However, when the cassette is not used, the slider 114 is positioned forward by the leaf spring 122 provided on the lower half 112. Is done.
[0008]
Two split-cylinder ribs are continuously connected to the bottom surface 112a of the lower half 112 perpendicularly to the side facing the space between the left and right projecting portions 112c and 112c (the side from which the magnetic tape is exposed). A wall-shaped member (reel area front wall) 112e provided in a letter shape is erected. The wall-shaped member 112e curved in the shape of a letter C is shaped so as to follow the magnetic tape winding ball wound around the winding hub 130, and the reel area is formed in the case. Forming. Then, columnar ribs 124 are erected vertically at substantially the center of the bottom surface portion 112f divided into a triangular shape by the wall-shaped member 112e. Between the columnar rib 124 and the wall-shaped member 112e, a C-shaped apex portion 122a of the leaf spring 122 is incorporated. The slider 114 is biased so as to be fixed at a front position by the leaf spring 122 when the cassette is not used. However, since the slider 114 receives a biasing force from the tip 122b of the leaf spring 22, the slider 114 is perpendicular to the front of the bottom surface 114a. Wall-shaped ribs 114c are provided.
[0009]
In FIG. 9, the upper half 110 and the lid 120 are turned upside down, and the inside is shown in a perspective view. In FIG. 9, the other side with the lid 120 is the front side. The lid 120 has side plates 120b that are vertically connected to the horizontal portion 120a at both left and right ends of a horizontal portion 120a that extends to the left and right. Then, the support pin 120 c provided inside the side plate 120 b is inserted into the pin support holes 110 c of the left and right flange portions 110 b provided on the bottom surface of the upper half 110. Accordingly, the lid 120 is rotatably supported by the flange portion 110b of the upper half 110. The ribs 110d and 110d provided in the vicinity of the flange portion 110b are brake member sliding guides for holding the brake member 116 and assisting its smooth sliding. The bosses 110e and 110e are for receiving the tape guides 112d and 112d of the lower half 112 during assembly.
[0010]
FIG. 10 shows another example of the upper half. The upper half 140 is the same as the upper half 120 in that the left and right flange portions 140a, 140a are provided with pin support holes 140b, 140b for receiving the spindle pins 120c, 120c of the lid 120. The upper half 140 is provided with a brake member sliding guide 142a integrated with a prism 142 which is a member for optically detecting the end of the magnetic tape 132. The brake member sliding guide 142a has a trapezoidal shape in which a columnar rib becomes thinner toward the tip, and a part of the outer side of the tip is cut out to form a stepped shape. It is intended to guide the sliding.
[0011]
FIG. 11 is a plan view showing a part of the state in which the upper half 110 and the lid 120 in FIG. 9 are combined. The lid 120 inserts a support pin 120b provided on the inner side of the side plate 120a into a pin support hole 110c (not shown in FIG. 11) of the flange portion 110b on the side of the upper half 110, and rotates around the support pin 120b. Is supported rotatably. The spindle pin 120b is provided with a lid spring 122, and urges the lid 120 to a position where the lid 120 closes the front surface of the cassette.
[0012]
[Problems to be solved by the invention]
However, in the conventional magnetic tape cassette as described above, when the lid 120 is assembled to the upper half 110 (or 140), the spindle pin 120b of the lid 120 is inserted into the pin support hole 110c (140b) of the upper half 110. In order to facilitate the rotation of the lid 120, the pin support hole 110c (140b) and the support pin 120b are required to have some allowance. Further, since the lid 120 is supported by the flange portion 110b (140b), the flange portion 110b (140a) is required to have a certain degree of strength.
[0013]
Therefore, as shown in FIG. 11, when the lid 120 is moved to the leftmost side of the drawing, there is a gap L between the locking pin 120b and the flange portion 110b, so that the lid 120 is shifted to the left and right. There was a problem of causing so-called looseness. In particular, if left and right play occurs in the deck, that is, when the lid 120 is in the open position, there is a problem that dust or the like due to play is scattered in the deck.
On the other hand, for example, it is conceivable that the backlash is restricted by the dimensions of the support pin 120b and the pin support hole 110c. In addition to the deterioration of the properties, there are problems such as powder falling off when the lid 120 slides, and it cannot be an effective measure against the rattling of the lid.
[0014]
The present invention has been made in view of the above-described conventional problems. It is easy to assemble a lid for protecting the magnetic tape on the front side of the magnetic tape cassette, and the right and left sides of the lid when the lid is in the open position when the magnetic tape cassette is used. It is an object of the present invention to provide a magnetic tape cassette that suppresses rattling.
[0015]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention comprises a cassette body that accommodates a pair of winding hubs wound with a magnetic tape, and a portion of the magnetic tape stretched between the pair of winding hubs. The upper half and the lower half are combined in a lid-like manner so as to be exposed on the front side of the cassette, the horizontal portion extends in the left-right direction of the cassette, and the side plate portions that are vertically connected to the horizontal portion at both left and right ends thereof. The spindle pin provided on the side plate portion is inserted into the pin support hole of the flange portion provided on the bottom surface of the upper half, and the front side of the magnetic tape exposed on the front side of the cassette is the horizontal portion. A magnetic tape cassette comprising: a closed position that covers and a front lid that is pivotable between an open position that opens the front side of the magnetic tape, wherein the front lid is in the open position When the side plate of the front lid is the upper half bottom Of like thickness of the side plate of the side opposite to the portion becomes thicker, to provide a magnetic tape cassette, characterized in that a thickness difference in the side plate portion.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a magnetic tape cassette according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.
[0017]
FIG. 1 is a plan view showing an upper half of a magnetic tape cassette and a part of a lid according to an embodiment of the present invention.
FIG. 1 corresponds to FIG. 11 and shows a state in which the lid 20 is assembled to the upper half 10 of the magnetic tape cassette 1. In the magnetic tape cassette 1 of the present embodiment, the constituent members other than the upper half 10 and the lid 20 shown in FIG. 1 are the same as those shown in the perspective exploded view of FIG.
[0018]
The lid 20 has side plate portions 20b vertically connected to left and right end portions of a horizontal portion 20a extending in the left-right direction of the magnetic tape cassette, and the support pin 20c provided inside the side plate portion 20b It penetrates into the pin support hole 10c of the flange part 10b provided in the bottom face 10a of the half 10. At the tip of the support pin 20c, a stopper 20d is provided when the support pin 20c is inserted through the pin support hole 10c. The spindle pin 20c is provided with a lid spring 22, which always urges the lid 20 to a closed position that protects the magnetic tape. When the magnetic tape cassette 1 is loaded into a deck (not shown), the lid 20 is rotated to the open position by the operation of the device in the deck, and when the magnetic tape cassette 1 is taken out from the deck, the lid spring 22 functions. The lid 20 automatically returns to the closed position.
[0019]
Further, the upper half 10 is provided with a brake member sliding guide 10d that holds a brake member (not shown) and ensures smooth sliding thereof. Reference numeral 10e denotes a boss for receiving the cylindrical tape guide of the lower half.
In this embodiment, when the lid 20 is in the open position, the side plate portion 20b is thick on the side plate portion 20b so that the portion of the side plate portion 20b that faces the side portion of the bottom surface 10a of the upper half 10 becomes the thick portion 20e. A difference is provided.
[0020]
A sectional view taken along line II-II in FIG. 1 is shown in FIG. As shown in FIG. 2, the shape of the thick part 20e provided in the side plate part 20b is thick only in the upper part in FIG. 2, and the lower part has the same thickness as the conventional one. This is to facilitate assembly when the lid 20 is assembled into the upper half 10, but the method of providing the thick portion is not limited to this. When the lid 20 is easily assembled to the upper half 10 and the lid 20 is in the open position, the thick wall portion 20e approaches the side of the bottom surface 10a of the upper half 10 so that the left and right play of the lid 20 is suppressed. Any shape and position may be used. In FIG. 2, when the lid 20 moves to the open position, the side plate portion 20 b moves in the direction indicated by the arrow A.
[0021]
FIG. 3 shows how the lid 20 moves to the open position. FIG. 3 is a perspective view of the portion of FIG. In FIG. 3, the lid spring 22, the brake member sliding guide 10d, the boss 10e, and the like are omitted for easy understanding.
FIG. 3A shows a state where the lid 20 is in the closed position. FIG. 3B shows a state where the lid 20 is rotated around the spindle pin 20c and is moved to the open position. As shown in FIG. 3B, as the lid 20 moves to the open position, the thick portion 20 e of the side plate portion 20 b gradually approaches the side portion 10 f of the bottom surface 10 a of the upper half 10. As a result, in the open position, back and forth of the lid 20 is suppressed.
[0022]
FIG. 4 shows another example of how to provide the thickness difference of the side plate portion 20b. 4 is a plan view showing a state in which the lid 20 is assembled to the upper half 10 of the magnetic tape cassette 1 as in FIG.
In this example, the thickness of the side plate portion 20b of the lid 20 is gradually increased toward the horizontal portion 20a, so that it becomes a tapered shape 20f. At this time, the shape of the bottom surface 10a of the upper half 10 may be the same as that of the above embodiment, but as shown in FIG. 4, in accordance with the tapered shape 20f of the side plate portion 20b, the tapered shape 10g is formed on the side portion of the bottom surface 10a. May be provided. In this way, when the lid 20 is assembled to the upper half 10, it can be easily assembled, and when the lid 20 is in the open position, the respective taper shapes 20 f and 10 g approach each other, and the lid 20. Left and right play is suppressed.
[0023]
Next, another example of preventing lid right and left play at the open position will be described.
In this example, unlike the embodiment, the thickness of the side plate portion of the lid is not changed, the thickness of the side plate portion is constant, and the left and right side plate portions are inclined inward toward the horizontal portion of the lid. In this way, when the lid is in the open position, the left and right side plate portions approach the left and right side portions of the upper half bottom surface to prevent the backlash of the lid at the lid open position.
[0024]
FIG. 5 shows a part of the upper half 10 and the lid 21 of the magnetic tape cassette 2 according to this example. FIG. 5 is a plan view corresponding to FIG.
The lid 21 of the magnetic tape cassette 2 of this example is indicated by a symbol B in FIG. 5 from the vicinity of the side plate portion 21b where the support pin 21c is provided toward the portion connected to the front horizontal portion 21a. As shown in FIG. Except for this point, the second embodiment is the same as the first embodiment, and detailed description thereof is omitted.
[0025]
FIG. 6 is a perspective view showing a state where the lid 21 of the magnetic tape cassette 2 of this example is slightly opened.
The lid 21 rotates toward the open position as shown by an arrow C in FIG. At this time, the left and right side plates in the portion where the side plate portions 21b and 21b are connected to the horizontal portion 21a, rather than the distance D between the left and right side plate portions 21b and 21b in the vicinity of the portion where the lid 21 is supported by the upper half 10 by the support pin 21c. The distance d between the portions 21b and 21b is smaller. That is, d <D.
[0026]
As a result, when the lid 21 is in the open position, the side plate portion 21b near the horizontal portion 21a approaches the bottom surface side portion 10f of the upper half 10, and the left and right sides of the lid 21 in the lid open position are the same as in the first embodiment. The backlash is suppressed.
In this example, as a result, the horizontal dimension of the horizontal portion 21a of the lid 21 is also slightly shortened compared to the conventional case, which also saves material.
[0027]
In the embodiment described above or another example, the lid 20 (or 21) is supported by the bottom surface side portion 10f of the upper half 10 in the open position. As a result, the flange portion 10b does not require that much strength as in the conventional case, and the thickness of the flange portion 10b can be made thinner than the conventional case. Further, the length of the support pin 20c (21c) can be shortened, and the stopper 20d (21d) can be reduced. As a result, as shown in FIG. 1 (or FIG. 5), the gap between the flange portion 10b and the spindle pin 20c (21c) when the lid 20 (21) approaches the innermost side (left side of FIG. 1 or 5). L ′ (or L ″) can be made smaller than the conventional gap L as shown in FIG.
Accordingly, the material can be reduced by reducing the members in the upper half 10 or the lid 20 (21), and the effective space in the cassette case can be expanded.
[0028]
By the way, recently, in order to increase the recording capacity of the magnetic tape, the winding of the tape is increased. Therefore, when using the magnetic tape in the deck, when the tape guide on the deck side pulls the magnetic tape out of the cassette case, the magnetic tape travel position moves to the outside by the amount of the tape wound ball and remains the same as before. However, there is a problem that the magnetic tape is rubbed against the flange portion of the upper half, the tip of the spindle pin, or the sliding guide.
[0029]
However, in the above-described embodiment, for example, the side plate portion 20b of the lid 20 is provided with the thick portion 20e on the side plate portion 20b so as to approach the side portion 10f of the upper half bottom surface 10a at the lid open position. Since the lid 20 is supported by the portion 10f, the flange portion 10b is thinned, and further, the flange portion 10b is slightly shifted outward, and the support pin 20c is also shortened (the stopper 20d is thinned). Is possible.
Therefore, even if the lid 20 is displaced, as shown by the alternate long and short dash line 30 in FIG. 7 when the magnetic tape is pulled out from the cassette case by the tape guide on the deck side, the displacement L ′ is negligible. Yes, the end of the spindle pin 20c does not hit the magnetic tape. Also, the sliding guide 10d can be prevented from contacting the magnetic tape by reducing its thickness or by removing a portion that may hit the magnetic tape.
In addition, the point which can prevent interference with a magnetic tape at the time of a magnetic tape traveling is also the same in other examples shown in FIG.
[0030]
The magnetic tape cassette of the present invention has been described in detail above. However, the present invention is not limited to the above examples, and various modifications and changes may be made without departing from the scope of the present invention. Of course.
[0031]
【The invention's effect】
As described above, according to the present invention, it is possible to effectively prevent the backlash of the lid, particularly when the magnetic tape is used in the deck, when the lid is in the open position.
[Brief description of the drawings]
FIG. 1 is a plan view showing a part of an upper half and a lid of a magnetic tape cassette according to an embodiment of the present invention.
2 is a cross-sectional view taken along the line II-II in FIG.
3A is a perspective view showing a portion of an upper half and a lid in FIG. 1, and FIG. 3B is a perspective view showing a state where the lid moves to an open position in the same portion.
FIG. 4 is a plan view showing another example of the upper half and the lid.
FIG. 5 is a plan view corresponding to FIG. 1 and showing another example of a magnetic tape cassette.
FIG. 6 is a plan view showing the upper half of the magnetic tape cassette and a part of the lid as in FIG. 1;
FIG. 7 is a perspective view showing another example of a magnetic tape cassette.
FIG. 8 is an exploded perspective view showing a conventional magnetic tape cassette.
FIG. 9 is a perspective view showing a state in which the upper half and the lid of FIG. 8 are turned over.
10 is a perspective view showing an example of an upper half different from FIG. 9. FIG.
11 is a plan view showing a part of a state where the upper half and the lid of FIG. 9 are combined. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Magnetic tape cassette 10 Upper half 10a Bottom face 10b Flange part 10c Pin support hole 10d Brake member sliding guide 10e Boss 10f (on the upper half bottom face) Side part 20 Lid 20a Horizontal part 20b Side plate part 20c Spindle pin 20d Detaching prevention 20e Thickness Meat 110, 140 Upper half 112 Lower half 114 Slider 116 Brake member 118 Brake spring 120 Lid 122 Leaf spring 130 Winding hub 132 Magnetic tape

Claims (1)

A cassette body that accommodates a pair of take-up hubs wound with magnetic tape is constructed, and the magnetic tape stretched between the pair of take-up hubs is coupled in a cover-like manner so that the front side of the cassette is exposed. Upper half and lower half,
The cassette has a horizontal portion extending in the left-right direction and side plate portions that are vertically connected to the horizontal portion at both left and right ends, and a support pin provided on the side plate portion is provided on the bottom surface of the upper half. It is inserted between the pin support holes of the flange portion, and is rotated between a closed position where the front side of the magnetic tape exposed on the cassette front side is covered with the horizontal portion and an open position where the front side of the magnetic tape is opened. A magnetic tape cassette provided with a movable front lid,
When the front lid is in the open position, the side plate portion has a thickness difference so that the thickness of the side plate portion of the portion facing the side portion of the upper half bottom surface is increased. A magnetic tape cassette characterized by the provision of

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