JP2000011597A - Magnetic tape cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occurrence of the sliding resistance and worn particle at the time of sliding between a restraint member for restricting the rotation of a reel in nonuse and a release member for releasing the restraint of the reel. SOLUTION: A single reel 2 wound with a magnetic tape is rotatably housed in a cartridge case 3, and a reel rotation restraining means 10 allowing the rotation of the reel 2 at the time of use and restricting it in nonuse is provided with the restraint member 4 for restricting the rotation by attachably/detachably moving against the reel 2, an energizing member 5 for energizing this restraint member 4 in the restraining direction, and the release member 6 for making the restraint member 4 move in the releasing direction by moving in accordance with the chucking operation of a rotation driving means 11 of the drive side while rotating integrally with the reel 2. At the time of injection molding of the restraint member 4 and the release member 6, the trace of gate is formed near the rotational center position of the reel 2 on the surface opposite to the surface where these members are slid each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cartridge, and more particularly to a magnetic tape cartridge in which a single reel having a magnetic tape wound in a cartridge case is rotatably accommodated.

[0002]

2. Description of the Related Art Conventionally, a magnetic tape cartridge used as a recording medium used for an external storage device such as a computer has a magnetic tape wound around a single reel.
A type in which this reel is rotatably housed in a cartridge case is known. Since this magnetic tape is used for data storage in computers and the like and stores important information, the magnetic tape should be pulled out carelessly so that troubles such as tape jamming do not occur and when not in use such as storage. To prevent the reel from rotating, a reel rotation stopping means for restricting the rotation of the reel is provided.

The reel rotation stopping means includes a stopping member which engages with a part of the reel and restrains the rotation of the reel, and when the cartridge is loaded into a drive such as an external storage device,
The stopping member is provided so as to release the stopped state in accordance with the reel chucking operation by the drive-side rotation driving means.

On the other hand, in order to improve the reliability of the operation of the above-described reel rotation restricting means and prevent dust from entering the cartridge case, the reel rotation restricting means has a restricting member for restricting the rotation of the reel, and a restricting member for restricting the rotation of the reel. It is conceivable to provide a structure in which a biasing member that biases the member in the stopping direction and a release member that moves in response to the chucking operation of the drive-side rotation drive unit and moves the stopping member in the release direction are separated.

In other words, in the non-use state, the magnetic tape is not pulled out by restraining the reel from being inadvertently rotated by the stopping member. When the reel is chucked, the release member moves in conjunction with the operation to release the stop member. In this state, the reel is rotatable, and the magnetic tape can be pulled out and wound up. At this time, since the release member is in contact with the stop member and rotates integrally with the reel, the release member rotates while sliding with the stop member.

[0006]

The releasing member or the stopping member described above is generally manufactured by injection molding.
This injection molding is indispensable to plastic molding technology as a technique for molding a product having a complex shape with high dimensional accuracy and high efficiency. (So-called gate mark) remains. Since the surface of the molded article is roughened unevenly due to the gate mark, if the gate mark is provided on the side of the releasing member or the stopping member that slides with each other, the sliding resistance of the releasing member and the stopping member is reduced by the unevenness of the gate mark. There is a problem that the size of the gate becomes large, which has an adverse effect on the rotation of the reel, or a gate mark is shaved to generate wear powder. For this reason, it is conceivable to provide a gate position of the mold so as to avoid a sliding portion of the release member or the stop member. However, since the release member or the stop member is formed so as to be point-symmetric or line-symmetric with respect to the rotation center of the reel in order to facilitate its manufacture, the sliding portion,
That is, if the gate position is provided so as to avoid the rotation center of the reel, the flow of the resin in the mold becomes uneven, and the dimensional accuracy of the release member or the stop member is deteriorated. In addition, since the speed at which the resin solidifies also differs for each part of the release member or the stopping member, the appearance of the resin may be mottled or the strength may be weak.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a magnetic tape cartridge capable of manufacturing a release member or a stop member accurately without adversely affecting the rotation of the reel. is there.

[0008]

According to the magnetic tape cartridge of the present invention, a single reel on which a magnetic tape is wound is rotatably accommodated in a cartridge case, and the reel is allowed to rotate during use. A magnetic tape cartridge provided with a reel rotation restraining means that sometimes restrains the rotation of the reel, wherein the reel rotation restraining means moves removably to and away from the reel and restrains the rotation of the reel; An urging member for urging the restricting member in the restricting direction; and a urging member that moves in response to the chucking operation of the drive-side rotation driving means to move the restricting member in the releasing direction, and slides with the restricting member integrally with the reel. A release member that rotates while moving, wherein the release member has an injection molding gate near the rotation center of the reel on the side opposite to the side sliding with the stop member. It is characterized in that it has a.

In the present invention, it is preferable that the stopping member also has a gate mark for injection molding near the rotation center of the reel on a side opposite to a side sliding with the releasing member.

Further, only the stopping member may have a gate mark for injection molding near the rotation center of the reel on the side opposite to the side sliding with the release member.

[0011]

According to the present invention as described above, the gate mark for injection molding is provided near the rotation center of the reel on the side of the release member and / or the stop member opposite to the side on which the slide member slides. The sliding resistance between the release member and the stopping member does not increase due to the unevenness of the trace, and no abrasion powder is generated. Further, since the gate mark is provided near the center of rotation of the reel, the flow of the resin in the mold becomes substantially uniform, so that the dimensional accuracy of the release member and / or the stop member does not deteriorate, and the appearance and the appearance are improved. A releasing member and / or a stopping member having good strength can be manufactured.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a sectional view of the magnetic tape cartridge according to this embodiment in a non-use state, FIG. 2 is an exploded perspective view of a main part, and FIG. 3 is a sectional view in a use state.

The magnetic tape cartridge 1 has a single reel 2 on which a magnetic tape (not shown) is wound, and an upper case 31.
And a lower case 32 provided with an opening 32a at the center thereof, and a lower case 32 fastened by screws or the like in a cartridge case 3;
The reel 2 is rotatably accommodated. Further, the magnetic tape cartridge 1 includes a reel rotation stopping means 10 for permitting the rotation of the reel 2 when in use and restricting the rotation of the reel 2 when not in use.

The reel 2 has a bottomed cylindrical reel hub 21 around which a magnetic tape is wound around the outer periphery, and a lower flange portion 22 and an upper flange portion which respectively protrude radially from the upper and lower ends of the reel hub 21 in a disk shape. The reel hub 21 and the lower flange 22 are integrally formed of a synthetic resin, and are connected to the upper flange 23 by, for example, ultrasonic welding. The lower portion of the reel hub 21 is closed at the center by a bottom wall 21a, and a reel gear 24 for rotating the reel 2 is engraved in an annular shape on an outer peripheral portion of a lower surface of the bottom wall 21a. Plate 25 made of annular metal plate for vacuum suction
Is attached. The reel gear 24 and the reel plate 25 of the reel 2 are
Are arranged so as to face the opening 32a on the bottom surface. The reel 2 is urged downward by an urging member 5 described later.

The drive-side rotary drive means 11 includes an annular drive gear 13 and a magnet (not shown) on the upper end surface of the rotary shaft 12, and its chucking operation is performed by inserting the so-called bucket into the bucket. The rotating shaft 12 moves upward with respect to the magnetic tape cartridge 1 moved below the drive device, and the drive gear 13 meshes with the reel gear 24, and the magnet plate attracts the reel plate 25 to maintain the meshed state.

Next, the mechanism of the reel rotation stopping means 10 will be described. The reel rotation restraining means 10 includes a restraining member 4 which moves up and down so as to be able to contact and separate from the reel 2.
A biasing member 5 for biasing the restraining member 4 in a restraining direction;
A release member 6 for moving the stop member 4 in the release direction.

The bottom wall 21a of the reel 2 has three insertion holes 2 penetrating vertically through the reel gear 24.
6 are arranged at regular intervals on the circumference, and three sets of six locking projections 27 are provided on the upper surface of the bottom wall 21a at a different phase position from the insertion hole 26 at regular intervals on the circumference. The tip of the locking projection 27 is formed in a gear tooth shape. In addition,
The insertion hole 26 and the locking projection 27 may be arranged in three or three or more sets, and the tip of the locking projection 27 may have a single gear tooth shape. The reel 2 shown in FIG.
Only the portion 1a is shown cut away.

The stopping member 4 has a substantially disc shape and is disposed inside the reel hub 21 of the reel 2 so as to face the bottom wall 21a. A stopping gear 41 is engraved in an annular shape on the outer periphery of the lower surface. The tip end of the locking projection 27 can mesh with the stopping gear 41. A cross-shaped engaging groove 42 is formed on the upper surface of the restraining member 4 so as to extend upward.
Engages with the rib 31a provided upright on the inner surface of the upper case 31 of the cartridge case 3 in a state where the rib 31a is not rotatably regulated, and the stopper member 4 moves toward and away from the bottom wall 21a of the reel 2 without rotating. It is installed as possible. The engagement groove 42 and the rib 31a may be provided linearly.

Further, an urging member 5 formed by a coil spring is contracted between the upper surface of the stopping member 4 on the outer peripheral side of the engaging groove 42 and the inner surface of the upper case 31 on the outer peripheral side of the guide portion 31a. The member 4 is urged downward in the stopping direction in which the stopping gear 41 and the locking projection 27 are engaged.

The release member 6 is vertically movably interposed between the stop member 4 and the bottom wall 21a of the reel hub 21. As shown in FIG. Extending columnar push-up portions 63 are provided. Each of the push-up portions 63 is movably inserted into an insertion hole 26 opened in the reel hub 21 so that the push-up portion 63 can move in and out, and its tip is located facing the tooth portion of the reel gear 24 on the lower surface of the reel hub 21. At this time, the locking projection 27 is
Located between three.

When the release member 6 is at the lowest position (FIG. 1), the lower end surface of the push-up portion 63 is located substantially at the tooth tip of the reel gear 24, and the drive gear is driven by the chucking operation of the drive rotation drive means 11 on the reel gear 24. The release member 6 is pressed in accordance with the engagement of the members 13 and is pushed up by a predetermined stroke amount (FIG. 3). The release member 6 rotates integrally with the reel 2 by fitting the push-up portion 63 into the insertion hole 26. Further, the stopping member 4 is urged by the urging member 5 such that the lower surface thereof comes into contact with the upper surface of the releasing member 6, and both of them come into sliding contact with the rotation of the reel 2.

FIG. 4 is a view showing a state in which the restraining member 4 is injection-molded. FIG. 4A is a sectional view showing an injection-molded state.
FIG. 4B is an enlarged view of a main part A of FIG. As shown in FIG. 4, the stopping member 4 is formed by injecting a resin from a runner 73 through a gate into a space formed by a fixed mold 71 and a movable mold 72. On this occasion,
A runner 73 is connected to a convex portion 43 formed at a rotation center position of the reel 2 on a surface of the stop member 4 opposite to a surface on which the release member 6 slides, and a movable mold is used to take out a molded product after molding. When the moving member 72 moves, the runner 73 moves
The gate mark 44 is formed on the projection 43.

FIG. 5 is a view showing a state in which the release member 6 is injection-molded, and FIG. 5A is a sectional view showing an injection-molded state.
FIG. 5B is an enlarged view of a main part B of FIG. As shown in FIG. 5, the release member 6 is formed by injecting a resin from a runner 76 through a gate into a space formed by a fixed mold 74 and a movable mold 75. On this occasion,
A runner 76 is connected to the rotation center position of the reel 2 on the surface of the release member 6 opposite to the surface on which the stop member 4 slides,
When the movable mold 75 moves to take out a molded product after molding, the runner 76 is cut off from the release member 6, and a gate mark 67 is formed here.

As described above, the stopping member 4 and the releasing member 6
By providing the gate traces 44 and 67 for injection molding near the rotation center of the reel 2 on the surfaces sliding with each other,
When the stop member 4 and the release member 6 slide, the stop member 4
The sliding resistance between the member and the release member 6 does not increase, and no abrasion powder is generated. Further, since the gate traces 44 and 67 are provided near the center of rotation, the flow of the resin in the molds 71, 72, 74 and 75 becomes substantially uniform, and the dimensional accuracy of the stopping member 4 and the releasing member 6 deteriorates. The stopping member 4 and the releasing member 6 can be manufactured with good appearance and strength.

The operation of the reel rotation stopping means 10 will be described. FIG. 1 shows a state where the magnetic tape cartridge 1 is not used, for example, in a storage state. In this state, the urging force of the urging member 5 causes the stopping member 4, The release member 6 and the reel 2 have moved to the lower case 32 side of the cartridge case 3, and the opening 32 a at the center of the lower case 32 is closed by the reel 2. The release member 6 has a lower surface formed on the bottom wall 21 of the reel hub 21.
a, which is in the lowest position in contact with the upper surface, and whose push-up portion 63 protrudes so that the leading end thereof coincides with the tooth tip position of the reel gear 24, and the stopping member 4 in contact with the upper surface of the release member 6 also moves down. In this position, the leading end of the locking projection 27 of the reel 2 is engaged with the stopping gear 41 to restrict the rotation of the reel 2 when not in use, thereby preventing the magnetic tape from being pulled out.

On the other hand, when the cartridge shown in FIG. 3 in which the magnetic tape cartridge 1 is loaded in the drive is used, the rotating shaft 12 of the drive-side rotating drive means 11 approaches the bottom surface of the reel 2 and the driving gear 1 is moved by the chucking operation.
When the gear 3 meshes with the reel gear 24 and moves the reel 2 slightly upward and holds it, the tooth tip of the drive gear 13 comes into contact with the tip of the push-up portion 63 of the release member 6 and presses it to push it up. Along with this, the release member 6 moves upward against the urging force of the urging member 5, and the stopping member 4 moves integrally with the release member 6 in the upward release direction. As a result, the engagement between the stopping gear 41 and the locking projection 27 is released, and the reel 2 becomes rotatable. Then, the magnetic tape is pulled out or wound up by the drive of the recording / reproducing apparatus.

In the above-described embodiment, the gate marks 44 and 67 are formed at the rotation center position of the reel 2 in the stop member 4 and the release member 6, however, the sliding surfaces of the stop member 4 and the release member 6 are not formed. If is formed on the opposite surface, there is no problem even if it is slightly shifted from the rotation center position.

In the above embodiment, the gate marks 44 and 67 are formed on the surface opposite to the sliding surface in both the stopping member 4 and the releasing member 6, but the stopping member 4 and the releasing member The gate trace may be formed on the surface opposite to the sliding surface in only one of the surfaces.

Further, in the above embodiment, the release member 6 is injection-molded as shown in FIG. 5, but the push-up portion 63 of the release member 6 is inserted into the insertion hole 26 and moves. Need to be erected vertically. However, the sink of the resin generated when the release member 6 is injection-molded may warp the plate portion 61 and make it impossible to accurately form the push-up portion 61. As shown in FIG. 5, a gate mark 67 is provided on the fixed mold 74 side.
And three push-up portions 63 are formed.
The sliding resistance between the fixed die 74 and the fixed die 74 increases,
When opening the movable mold 4 and the movable mold 75, the release member 6 is removed to the fixed mold 74 side, so that there is a problem that the molded product cannot be smoothly removed from the molds 74 and 75.

For this reason, as shown in FIG.
It is preferable to form a hole 6a at a position corresponding to the push-up portion 63 on the side facing the movable mold 75 so that the push-up portion 63 becomes thin. That is, a pin-shaped convex portion 75a is formed at a position corresponding to the push-up portion 63 of the movable mold 75, and when the release member 6 is injection-molded, the hole 6 is formed in the release member 6.
a may be formed. Here, since the position corresponding to the push-up portion 63 in the release member 6 is located away from the gate, when the resin is solidified, the contraction is large. Therefore, when the release member 6 is solidified in the molds 74 and 75, the hole 6a shrinks and the protrusion 75a of the movable mold 75
Will be generated. Thereby, the mold 7
When the release members 4 and 75 are released, the release member 6 is prevented from being taken by the fixed mold 74, so that the release of the molds 74 and 75 and the removal of the molded product can be performed smoothly.

Further, by making the push-up portion 63 uniform in thickness, sink of the resin can be prevented, whereby the push-up portion 63 can be prevented from falling down during molding, and as a result, the dimensional accuracy of the push-up portion 63 can be improved. Can be.

[Brief description of the drawings]

FIG. 1 is a sectional front view of a magnetic tape cartridge according to an embodiment of the present invention in a non-use state.

FIG. 2 is an exploded perspective view of a main part of the magnetic tape cartridge of FIG.

FIG. 3 is a sectional view of the magnetic tape cartridge of FIG. 1 in a state of use;

FIG. 4 is a diagram showing an injection molding state of a stopping member.

FIG. 5 is a view showing an injection molding state of a release member (part 1).

FIG. 6 is a diagram showing an injection molding state of a release member (part 2).

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 magnetic tape cartridge 2 reel 3 cartridge case 4 restraining member 5 urging member 6 release member 10 reel rotation stopping means 11 drive-side rotation drive means 12 rotation shaft 13 drive gear 21 reel hub 21a bottom wall 24 reel gear 25 reel plate 26 insertion hole 27 Locking protrusion 41 Stopping gear 44, 67 Gate mark 63 Push up 74 Fixed mold 75 Movable mold

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoo Morita 2-12-1, Ogimachi, Odawara City, Kanagawa Prefecture Inside Fuji Photo Film Co., Ltd. (72) Hideaki Shiga 2-12-1, Ogimachi, Odawara City, Kanagawa Prefecture Inside Fuji Photo Film Co., Ltd. (72) Inventor Yusuke Ishihara 2-12-1, Ogimachi, Odawara City, Kanagawa Prefecture Inside Fuji Photo Film Co., Ltd.

Claims (3)

[Claims] 1. A reel rotation stopping means which rotatably accommodates a single reel wound with a magnetic tape in a cartridge case, permits rotation of the reel when in use, and restricts rotation of the reel when not in use. A magnetic tape cartridge comprising: a reel rotation restricting means, a restricting member that is movable to and away from the reel to restrict rotation of the reel, and a biasing member that biases the restricting member in a restricting direction. And a release member that moves in response to the chucking operation of the drive-side rotation drive unit, moves the stop member in the release direction, and rotates integrally with the reel while rotating with the stop member. The magnetic tape cartridge, wherein the release member has a gate mark for injection molding near a rotation center of the reel on a side opposite to a side sliding with the stopping member. 2. The stopping member has an injection molding gate mark near a rotation center of the reel on a side opposite to a side sliding with the releasing member.
The magnetic tape cartridge as described in the above. 3. A reel rotation stopping means which rotatably accommodates a single reel wound with a magnetic tape in a cartridge case, permits rotation of the reel when in use, and restricts rotation of the reel when not in use. A magnetic tape cartridge comprising: a reel rotation restricting means, a restricting member that is movable to and away from the reel to restrict rotation of the reel, and a biasing member that biases the restricting member in a restricting direction. And a release member that moves in response to the chucking operation of the drive-side rotation drive unit, moves the stop member in the release direction, and rotates integrally with the reel while rotating with the stop member. The magnetic tape cartridge, wherein the stopping member has a gate mark for injection molding near a rotation center of the reel on a side opposite to a side sliding with the releasing member.