JP2000011594A - Magnetic tape cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evade the disturbance in the entering/leaving operation with respect to a drive or the loading/unloading work with respect to a library caused by the trace of gate at the time of injection molding for a magnetic tape cartridge and also to attain the molding with the high dimensional accuracy by the gate of one point for the injection molding without the unevenness of resin. SOLUTION: In the magnetic tape cartridge 1 housing a single reel wound with the magnetic tape in a resin cartridge case whereon an opening part 26 for pulling out the magnetic tape is formed on the side wall, the position of the gate for the injection molding is set on recessed parts 10 arranged on the surface of the center thick part 10 of an upper cartridge case 2 of the magnetic tape cartridge 1, or recessed parts 14, 15 for the purpose other than the setting of the gate position, or a recessed part 36 for stacking, or a recessed part arranged on the surface of a projecting part for stacking, or a recessed part arranged on the area of the reference hole side surrounded with a center line of a lower cartridge case and a straight line passing the reference hole perpendicular to the center line, or in the area extended backward in the cartridge loading direction from the projecting part for stacking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-reel type magnetic tape cartridge used for a computer or the like.

[0002]

2. Description of the Related Art Conventionally, a magnetic tape cartridge (hereinafter, also referred to as "cartridge") for accommodating a magnetic tape used as a recording medium used in an external storage device such as a computer includes a magnetic tape mounted on a single reel. The reel is rotatably stored in the cartridge case, and one end of the magnetic tape is pulled out to the device side from the magnetic tape draw-out opening provided on the side wall of the cartridge case to be used for one reel type. Are known.

The main body of the cartridge case is generally manufactured by injection molding.

A magnetic tape cartridge is used by being mounted on a recording / reproducing device (hereinafter, referred to as a "drive") such as an external storage device. At the time of loading, the magnetic tape cartridge is positioned at a predetermined position in the drive. Positioning is performed with reference to a reference hole provided on the bottom surface of the cartridge case and the outer wall surface of the cartridge case itself. In some cases, the cartridges are stored in the library by arranging them in the library.However, the cartridge case is provided with a stacking projection and a concave portion that engage with each other in order to prevent the cartridges from shifting when stacked in the library. At the time of use, a desired cartridge is taken out of the library and loaded into a drive for use.

[0005]

The above-mentioned injection molding is indispensable to plastic molding technology as a technique for producing a product having a complicated shape with high dimensional accuracy and high efficiency. However, during molding, a gate mark is left on the surface of the product, and depending on the position, the gate mark may cause a problem in a drive insertion / removal operation when a cartridge is loaded into or removed from the drive.
For example, the cartridge may be caught inside the drive due to the trace of the gate, or may be shaved to generate powder.

[0006] In addition, when a library is inserted or removed from a library by taking out a desired cartridge from a library by a chucking machine and loading the cartridge into the drive, or taking out a cartridge from the drive and storing it in the library, a part of a cartridge case rear side inserted into the drive is used. Must be pinched by the chucking claw, but it is necessary to stably chuck the library to perform the library entry and exit correctly, but if there is a gate mark on the surface of the cartridge case,
There is a problem that it hinders stable library access work.

If the gate position is provided in an arbitrary concave portion of the cartridge, the above problem can be avoided, but the flow of resin naturally deteriorates because the thickness of the cartridge case near the gate is thin. As a result, unevenness of the resin occurs around the gate, or the resin pressure is not sufficiently applied, so that the flow end (side wall or the like) is opened and the dimensional accuracy is deteriorated. In some cases, the resin does not flow to the side wall and a so-called short shot occurs. There is a problem that occurs. Therefore, it is conceivable to secure a stable resin flow by using a plurality of injection molding gates, but a problem remains in terms of cost and the like.

It is also conceivable to provide a tunnel gate or a side gate on the side surface or the like, but the flow length of the resin becomes long, and it is difficult to secure dimensional accuracy.

The present invention has been made in view of the above circumstances, and a single injection molding gate is used to form a fine shape with high dimensional accuracy, and does not affect the cartridge case entry / exit operation and library entry / exit operation. It is an object of the present invention to provide a magnetic tape cartridge.

[0010]

According to the magnetic tape cartridge of the present invention, a single reel on which a magnetic tape is wound can be rotated in a resin cartridge case having a magnetic tape draw-out opening formed in a side wall. In the magnetic tape cartridge accommodated in the cartridge case, the cartridge case has a thick portion at least a central portion of an upper wall and a lower wall, and at least one concave portion is provided on an outer surface of the thick portion, A gate position for molding the cartridge case is provided in the recess.

Here, "the central portion of at least one of the upper wall and the lower wall" is a portion located at substantially the center of at least one of the upper wall and the lower wall of the cartridge case,
The flow length of the resin flowing during the injection molding becomes substantially uniform, and to the extent that the molded product does not have a problem as a product, it refers to a position where the resin can flow without resin unevenness, as a specific example, the upper wall of the cartridge case or Starting from the center of the lower wall,
40 of the length from the center to the outer circumference of the cartridge case
%, More preferably 25%. The “thick portion” refers to a portion of the upper wall or the lower wall of the cartridge case having a wall thickness larger than the basic wall thickness.

When the recess provided with the gate position is deviated from the center of the cartridge case, it is desirable to provide the recess in a region near the magnetic tape drawing-out opening on the outer surface of the thick portion.

In the magnetic tape cartridge of the present invention, a single reel wound with a magnetic tape is rotatably housed in a resin cartridge case having a magnetic tape draw-out opening formed in a side wall. In the magnetic tape cartridge, the cartridge case is provided with a concave portion on at least one of an outer surface of an upper wall and a lower wall thereof for a purpose other than setting a gate position at the time of molding the cartridge case. Is provided. A “recess provided for a purpose other than setting the gate position when forming the cartridge case” is not a recess specially provided for setting the gate position on the outer surface of the cartridge case, but may be a function for other purposes. In terms of design or design, it refers to the part formed as a recess.
It may be an insertion mark, a slip prevention portion, or a portion formed with a grip pattern and formed as a recess.

The "recess provided for a purpose other than the setting of the gate position at the time of molding the cartridge case" is a stacking recess engaged with the stacking protrusion of the adjacent magnetic tape cartridge when the magnetic tape cartridges are stacked in the vertical direction. It may be. "Stacking recess"
Is a concave portion for preventing the upper and lower cartridges from shifting each other when stacking the cartridges in the vertical direction,
The shape is not particularly limited. In this case, the concave portion has a depth necessary for stacking, and it is desirable to make the whole or a part deeper than the original shape so that the gate mark does not interfere with the stacking convex portion.

In the magnetic tape cartridge of the present invention, a single reel on which a magnetic tape is wound is rotatably accommodated in a resin cartridge case having an opening for drawing out a magnetic tape on a side wall. In the magnetic tape cartridge, the cartridge case is provided with a stacking projection for vertically stacking the magnetic tape cartridges, the projection is provided with a recess, and the recess is provided with a gate for molding the cartridge case. It is characterized in that a position is provided. The “stacking projection” is a projection for preventing the upper and lower cartridges from shifting from each other when the cartridges are stacked in the vertical direction, and the shape is not particularly limited.

In the magnetic tape cartridge of the present invention, a single reel on which a magnetic tape is wound is rotatably housed in a resin cartridge case having a magnetic tape draw-out opening formed in a side wall. In the magnetic tape cartridge, the cartridge case is provided with at least two reference holes for positioning the cartridge case in the recording / reproducing apparatus, and the center of the cartridge case is parallel to a straight line connecting the reference holes. A recess is provided on the outer surface of a region on the reference hole side surrounded by a center line passing through the reference hole and a straight line passing through the reference hole perpendicular to the center line, and the recess is provided with a gate position at the time of molding the cartridge case. It is characterized in that it is.

Further, in the magnetic tape cartridge of the present invention, a single reel wound with a magnetic tape is rotatably accommodated in a resin cartridge case having a magnetic tape draw-out opening formed in a side wall. In the magnetic tape cartridge, the cartridge case is provided with a stacking projection for vertically stacking the magnetic tape cartridges in the loading direction of the recording / reproducing apparatus, and the cartridge case outer surface is A gate position at the time of forming the cartridge case is provided in a region extending from the stacking projection to the rear in the magnetic tape cartridge loading direction. Here, "the area extending from the stacking projection to the rear in the magnetic tape cartridge loading direction" refers to the stacking projection located on the front side with respect to the loading direction of the magnetic tape cartridge loaded in the drive. Means the area located behind and without contact with the drive.

[0018]

According to the magnetic tape cartridge of the present invention, the gate position at the time of molding the cartridge case is formed in the concave portion provided on the outer surface of the thick portion located at the center of at least one of the upper wall and the lower wall of the cartridge case. Is provided, the flow length of the resin at the time of molding becomes substantially uniform, and the thickness of the cartridge case near the gate due to the provision of the concave portion can be prevented from becoming thin, so that the flow of the resin becomes smooth. As a result, resin unevenness around the gate can be prevented, and problems such as sinking of the flow end (side wall and the like), poor dimensional accuracy, and short shot can be solved. In addition, since the gate position is provided in the concave portion, the problem that the cartridge is caught in the drive due to the gate trace or the powder is generated due to the trace of the gate at the time of the drive in / out operation is solved, and the chucking can be stably performed at the time of the library access operation. .

A gate at the time of molding is formed in a concave portion provided in a region near the magnetic tape drawing-out opening portion on the outer surface of the thick portion located at the center of at least one of the upper wall and the lower wall of the cartridge case. When provided, the resin flows through the opening side having many ribs, so that resin unevenness can be effectively prevented.

The magnetic tape cartridge according to the present invention may be provided in a recess provided on the outer surface of at least one of the upper wall and the lower wall for a purpose other than the setting of the gate position when the cartridge case is formed, or in a stacking recess. Since the gate position is provided when molding the case, the cartridge remains trapped inside the drive due to the gate marks when the drive enters and exits, and there is a problem that powder is generated when the drive enters and exits without having to provide a recess for setting the gate position again. This is resolved, and stable chucking can be performed when entering and exiting the library.

Further, in the magnetic tape cartridge according to the present invention, the concave portion for setting the molding gate is provided in the stacking convex portion, so that the thickness of the cartridge case near the gate due to the provision of the concave portion is prevented from becoming thin. Therefore, the flow of the resin is smooth, the resin unevenness around the gate can be prevented, and the flow ends (side walls, etc.)
Problems such as sink marks, poor dimensional accuracy, and short shots are eliminated.

Further, in the magnetic tape cartridge according to the present invention, a center line passing through the center of the cartridge case parallel to a straight line connecting a reference hole for positioning in the recording / reproducing apparatus, and the reference hole perpendicular to the center line. Since the concave portion is provided on the outer surface of the region on the side of the reference hole surrounded by a straight line passing through, a sufficient and appropriate resin pressure can be applied around the reference hole to solidify, so that the reference hole is accurately formed. It is possible to improve the positioning accuracy of the cartridge.

Still further, the magnetic tape cartridge according to the present invention extends rearward in the magnetic tape cartridge loading direction from a stacking projection for vertically stacking the magnetic tape cartridges in the loading direction to the recording / reproducing apparatus. By providing a gate position for forming the cartridge case in the area, this area does not come into contact with the inside of the drive. The entry / exit operation and library entry / exit operation can be performed smoothly.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnetic tape cartridge according to the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing the entire structure of a magnetic tape cartridge according to an embodiment of the present invention.

As shown in FIG. 1, the cartridge 1 according to the embodiment of the present invention has a magnetic tape 20 on a single reel 4 in which a lower reel 5 and an upper reel 6 are joined by ultrasonic welding.
And the reel 4 is rotatably housed in a cartridge case 7 in which the upper cartridge case 2 and the lower cartridge case 3 are fastened by screws or the like. An opening 26 for drawing out the magnetic tape 20 is formed on one side wall of the cartridge case 7. A slide door 27 that is movable in the direction of arrow A parallel to the side wall of the cartridge case 7 is attached to the opening 26. When the cartridge 1 is not used, the magnetic tape 20 is completely wound on the reel 4 and the magnetic tape 20 is not used.
The leader pin 21 attached to the end of the opening is locked in a recess 28 formed near the opening 26.

When the cartridge 1 is inserted into the drive in the loading direction X and is set at a predetermined position in the drive, the brake button 9 moves upward in the figure against the urging force of the coil spring 10, whereby The locking of the braking gears 9A, 23A between the brake button 9 and the reel hub 23 is released, so that the reel 4 is rotatable, and the magnetic rotary driving means is fitted to the reel 4 to rotate the reel 4. . At the same time, the leader pin 21 is pulled into a predetermined position on the tape running path, and data can be read from and written to the magnetic tape 20.

Hereinafter, the gate position when the cartridge case 7 is injection-molded will be described.

FIG. 2 is a perspective view of the external shape of the cartridge viewed from the upper cartridge case, and FIG.
FIG. 4 is a cross-sectional view of the upper cartridge case taken along the line, as viewed from the direction of the arrow. FIG.

As shown in FIG. 3, the upper cartridge case 2 has two thick portions 12 and 13 formed at the center of the upper wall 11. That is, the rib 31 is located at the center of the upper wall 11.
The portion where the rib 31 is provided is a thick portion 12 having a wall thickness larger than the basic wall thickness (base wall thickness) t ₀ of the upper wall 11. An annular rib 32 is provided on the outer periphery.
Also part is provided and has a thick portion 13 the wall thickness is greater than the basic wall thickness t _0. The upper cartridge case 2 has a thick portion 1 at the center of the upper wall 11.
A concave portion 10 is provided at a central position indicated by an arrow A on the outer surface 2 (also the central position of the upper wall 11), and an injection molding gate is set in this concave portion 10 for injection molding.

The recess 10 for setting the position of the gate for injection molding is not limited to the portion of the thick portion 12 indicated by the arrow A.
The outer surface of the thick portion 13 may be provided anywhere as long as it is the outer surface of the thick portion in the center portion of the upper wall 11. For example, a region (closer to the center of the upper wall 11 than the center of the upper wall 11) Can also be provided at the portion indicated by the arrow B which is a region near the opening 26).

Since the gate position for injection molding is set in the concave portion formed on the outer surface of the thick portion at the center of the upper wall 11 as described above, the gate position is located at the center of the upper wall. Since the resin flow length can be made uniform when the cartridge case 2 is molded, and the gate position is set in the concave portion 10, the gate mark protrudes from the outer surface of the upper wall, which hinders the drive access operation and library access operation. In addition, since the concave portion 10 is formed in the thick portion, the wall thickness near the gate can be maintained larger than when the concave portion 10 is formed in a portion other than the thick portion. Can be avoided.

When the concave portion 10 is provided not in the central portion indicated by the arrow A but in the portion indicated by the arrow B, that is, at a portion closer to the magnetic tape drawing-out opening portion 26 in the thick portion at the central portion, the opening In the vicinity of the portion 26, there are more ribs than in other portions, and more resin is required. Therefore, compared with the case where the rib is provided in a portion far from the opening 26, for example, a portion indicated by an arrow C, the vicinity of the opening 26 is larger. This is advantageous because the resin can be more reliably supplied to the ribs.

When the gate is a bubble gate, the recess 10
The whole may be a gate. In this case, the recess 10 can be made small so that the gate mark is not conspicuous.

In the above example, the upper cartridge case 2 is injection-molded. However, also in the injection molding of the lower cartridge case 3, if a thick portion exists at the center of the lower wall 22, A concave portion can be formed on the outer surface of the thick portion, and a gate position can be provided in the concave portion.

The gate position can be provided in a concave portion provided for a purpose other than the setting of the gate position in both the upper and lower cartridge cases 2 and 3. For example, in the case of the upper cartridge case 2, a portion indicated by an arrow D in an insertion mark 14 which is a recess formed in the case 2, a portion indicated by an arrow E in a slip prevention portion 15 which is also a recess,
Alternatively, in the case of the lower cartridge case 3, the lower cartridge case 3 can be provided in a grip pattern portion 33 which is a concave portion formed in the case 3. Since these portions are already concave portions in terms of function or design, it is not necessary to newly provide a concave portion for setting the gate position, which is convenient.

Further, the gate position can be provided in a portion indicated by an arrow F in the stacking concave portion 36 of the upper cartridge case 2. Since the inside of the stacking concave portion 36 overlaps with the stacking convex portion 35 of the lower cartridge case 3, a gate mark is formed on the stacking convex portion 35.
It is preferable that a part or the whole of the stacking recess 36 is slightly deepened so as not to interfere with the above. Note that the stacking projections 35 and the stacking recesses 36 are not limited to the shapes shown in the figure, and may be, for example, elongated in the loading direction of the cartridge case 7.

The above-mentioned stacking convex portion 35 and concave portion 3
Numeral 6 is used to prevent the positional deviation between the upper and lower cartridges by engaging the convex portions 35 and the concave portions 36 of the upper and lower cartridges when the cartridges 1 are vertically stacked. Although the concave portion 36 is provided with the convex portion 35 in the lower cartridge case 3, it is of course possible to provide the convex portion 35 in the upper cartridge case 2 and the concave portion 36 in the lower cartridge case 3. In the injection molding of the case 3, a gate position can be provided in the stacking concave portion 36.

The above gate position is determined by focusing on two reference holes 34 for positioning the cartridge 1 provided in the lower cartridge case 3 at a predetermined position in the recording / reproducing apparatus, and a straight line connecting the reference holes 34 to each other. A concave portion is provided on the outer surface of a region 39 surrounded by a center line 17 passing through the center of the lower cartridge case 3 parallel to 16 and straight lines 18 and 19 perpendicular to the center line 17 and passing through the reference hole 34. Can also be set. The recess may be in this region, but may be located at the same distance from the two reference holes 34, and further, may be recessed at the center of the region connecting the two reference holes 34, for example, on the outer surface of the portion indicated by arrow G in the figure. Is preferably set in the recess. If a gate position for injection molding is provided in this area, the resin can flow from the gate to both reference holes 34 without resin unevenness, and both reference holes can be formed with high precision. Also in this case, when the reference hole 34 is provided in the upper cartridge case 2, the upper cartridge case 2 is injection-molded by forming a concave portion in the central portion of a region connecting the reference hole 34 and providing a gate position in the concave portion. be able to.

The gate position is determined by forming a concave portion at the tip end surface of the stacking convex portion 35 formed on the lower cartridge case 3 (the end surface in the direction in which the convex portion 35 protrudes), for example, at the portion indicated by the arrow H. It can also be provided in the recess.

Further, the gate position is indicated by an arrow I which is a central portion of the area, for example, in an area 38 provided in the lower cartridge case 3 on the rear side in the drive loading direction of the stacking projection 35. It may be provided at a portion (may be a central portion of the left region 38 in the figure). This area 38 does not need to be provided with a recess because the stacking projection 35 does not contact the inside of the drive even if the gate mark is present on the surface when the cartridge 1 moves in the drive. It is convenient.

In the above two cases, when the stacking projection 35 is formed on the upper cartridge case 2, injection molding of the upper cartridge case 2 is performed by forming a recess on the surface of the stacking projection 35, Alternatively, a recess may be formed in an area 38 behind the stacking projection 35 in the drive loading direction, and a gate position may be provided in the recess.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing the overall configuration of a magnetic tape cartridge according to an embodiment of the present invention.

FIG. 2 is a perspective view of the external shape of the cartridge viewed from the upper cartridge case side.

FIG. 3 is a cross-sectional view of the upper cartridge case taken along the line SS shown in FIG.

FIG. 4 is a perspective view of the external shape of the cartridge viewed from a lower cartridge case side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic tape cartridge 2 Upper cartridge case 3 Lower cartridge case 7 Cartridge case 26 Magnetic tape drawer opening 35 Stacking convex part 36 Stacking concave part

Claims (7)

[Claims] 1. A magnetic tape cartridge comprising a resin cartridge case having a magnetic tape draw-out opening formed in a side wall, and a rotatable single reel wound with a magnetic tape housed therein. At least one of the upper wall and the lower wall of the case has a thick central portion, and at least one concave portion is provided on the outer surface of the thick portion, and a gate position at the time of molding the cartridge case is provided in the concave portion. A magnetic tape cartridge characterized by being manufactured. 2. The concave portion provided with the gate position is a concave portion provided in a region near the magnetic tape drawing-out opening portion on the outer surface of the thick portion. The magnetic tape cartridge as described in the above. 3. A magnetic tape cartridge wherein a single reel on which a magnetic tape is wound is rotatably housed in a resin cartridge case having a magnetic tape draw-out opening formed in a side wall. A case in which a concave portion is provided on at least one of the outer surfaces of the upper wall and the lower wall for a purpose other than the setting of the gate position when the cartridge case is formed, and the concave portion is provided with a gate position when the cartridge case is formed. A magnetic tape cartridge characterized by the following. 4. The magnetic device according to claim 3, wherein the concave portion is a stacking concave portion which engages with a stacking convex portion of an adjacent magnetic tape cartridge when the magnetic tape cartridges are vertically stacked. Tape cartridge. 5. A magnetic tape cartridge in which a single reel on which a magnetic tape is wound is rotatably housed in a resin cartridge case having a magnetic tape drawer opening formed in a side wall. The case is provided with a stacking projection for vertically stacking the magnetic tape cartridges, a recess is provided in the projection, and a gate position is provided in the recess when the cartridge case is molded. A magnetic tape cartridge characterized by the above-mentioned. 6. A magnetic tape cartridge in which a single reel on which a magnetic tape is wound is rotatably housed in a resin cartridge case having a magnetic tape drawer opening formed in a side wall. The case is provided with at least two reference holes for positioning the cartridge case in the recording / reproducing apparatus;
A recess is provided on an outer surface of a region on the reference hole side surrounded by a center line passing through the center of the cartridge case parallel to a straight line connecting the reference hole and a straight line passing through the reference hole perpendicular to the center line. A magnetic tape cartridge, wherein the recess is provided with a gate position at the time of molding the cartridge case. 7. A magnetic tape cartridge in which a single reel on which a magnetic tape is wound is rotatably housed in a resin cartridge case having a magnetic tape draw-out opening formed in a side wall. A case is provided with a stacking protrusion for vertically stacking the magnetic tape cartridges in the loading direction of the recording / reproducing apparatus, and the magnetic tape cartridge is mounted on the outer surface of the cartridge case from the stacking protrusion. A magnetic tape cartridge, wherein a gate position at the time of molding a cartridge case is provided in an area extending rearward in the loading direction.