Abstract: A magnetic tape cartridge includes a reel around which a magnetic tape is wound, a cartridge case rotatably accommodating the reel, a reel lock for locking rotation of the reel relative to the cartridge case, a resilient member urging the reel lock toward the reel, a release pad for disengaging the reel lock by displacing the reel lock against an urging force of the resilient member, so as to allow rotation of the reel, and a pivot provided on the reel lock at a position facing with and slidably contacting a contact surface of the release pad in a manner allowing rotation of the release pad. The pivot and the contact surface are both made of resin, and the contact surface is made of a resin having a higher hardness than the pivot.

Abstract: There is provided a magnetic tape, to be used at a running speed of at least 4,000 mm/sec., wherein servo signals for controlling tracking are recorded on the magnetic layer or the backcoat layer, and wherein the difference between the recording track width and the reproducing track width is 16 ?m or less, characterized in that the value of [?/(Tw?Tr)] is 0.2 or less, wherein a [?m] is an amount of a weave occurring on one of both edges of the magnetic tape and on the side of reference for the running of the tape; Tw [?m] is a recording track width; and Tr [?m] is a reproducing track width; and that a coefficient of humidity expansion in the tape widthwise direction is (0 to 14)×10?6/% RH; and a coefficient of thermal expansion in the tape widthwise direction is (0 to 10)×10?6/° C.

Abstract: A cartridge case includes a first case and a second case that are fitted together to form a cartridge body capable of housing an information recording carrier therewithin. The first case is constructed by attaching a reference hole forming member, in which a positioning reference hole is formed, to a main plate of the first case.

Abstract: The present invention is a laminate media, in the form of a continuous strip of carrier-less, pre-cut plastic patch protections, connected by perforations. The invention further describes both a method for separating the patches from each other by stressing the perforated patch area without stopping the driving process and a cassette within which the separation process occurs.

Abstract: The present invention aims to provide a magnetic tape cartridge capable of improving operational precision and efficiency in the process of mounting a release part for unlocking a reel. A magnetic tape cartridge having a release button (part) for unlocking a reel, the release button being mounted in a hub with a cup shape formed on the reel, wherein a bottom portion of the hub has a fitting opening into which the release part fits, and a detection opening with a predetermined positional relationship with the fitting opening; and a reflection (metal) plate attached on a bottom surface of the bottom portion of the hub is viewed from an aperture of the detection opening defined in a top surface of the bottom portion of the hub.

Abstract: A reel which rotates to wind or feed out the recording or recordable tape wound therearound is set in a cartridge. The reel rotation is locked by a reel lock that seizes the reel by being pushed against the reel with a spring and is unlocked by the release pad pushed back against the force of the spring. The release pad has a pivot, of which tip has a partial globe shape head, on the surface facing to the reel lock and the reel lock has a recess on the surface facing to the release pad. The curvature of the recess is larger than that of the pivot. The head of the pivot contacts within the recess. Then the pivot and the recess on reel lock surface can keep uniformly wear out in tape winding or feeding out and the reel lock hardly generates sound noise in the operation.

Abstract: A magnetic tape cartridge made up of a cartridge case composed of an upper and lower cases welded together on the mating surfaces by ultrasonic welding with a plurality of energy directors, and a single reel of magnetic tape rotatalby retained in the case, in which the weld deposits formed by the energy directors may be prevented from sticking out of the mating surfaces. A plurality of energy directors provided on one of the mating surfaces have an elongated shape, and are disposed with the longitudinal direction substantially perpendicular to the direction along the side wall of the upper and lower cases.

Abstract: In a recording tape cartridge, a braking member positioned at a restricting position within a reel hub in a state of abutting an inner surface of a floor plate of a case when the recording tape cartridge is not in use, is held at the restricting position by a top end surface of the braking member abutting a bottom end surface of a clutch member. Upward movement of a reel is restricted. When a release operation portion is pushed by a releasing portion of a drive device and the clutch member rotates, due to cam grooves and cam projections converting torque of the clutch member into axial direction moving force, the braking member, whose held state is cancelled by the bottom end surface sliding along the top end surface, moves to a rising-up permitting position, such that rising-up of the reel within the case is permitted.

Abstract: When a recording tape cartridge is not in use, rotation of a reel, which abuts an annular rib of a floor plate of a case, is locked by a braking member which meshes together from above with an engaging gear, and a gap between the braking member and a spacer wall of a ceiling plate is filled-in by a spacer portion of a spacer member, and movement away from the annular rib is impeded. When, due to operation of a drive device, the spacer portion enters into a relief portion of the braking member which relief portion opens upwardly, the braking member is raised up by an amount corresponding to the gap formed between the braking member and the spacer wall, and meshing of the braking member and the engaging gear is cancelled. The reel thereby becomes able to rotate and to move away from the annular rib.

Abstract: A reel has: a hub which is cylindrical, which is molded of a resin material, and around which a recording tape is wound; and a flange provided at an end portion of the hub, and holding a transverse direction end portion of the recording tape. A ring-shaped member formed of metal is provided at the hub by insert molding. In accordance with the present invention, there is provided a reel in which can maintain a highly-accurate configuration of the hub, regardless of environmental changes.

Abstract: A roll holder device is for use with a recording paper roll including a tubular spool shaft and continuous recording paper wound about the tubular spool shaft in a roll form. In the roll holder device, first and second holder cores are inserted in respectively first and second ends of the tubular spool shaft. A holder frame supports the first and second holder cores in a rotatable manner. Anti-dropping levers prevent the tubular spool shaft from dropping from the first and second holder cores by pushing a shaft inner surface of the tubular spool shaft.

Abstract: The present magnetic tape cartridge having a data storage medium connected to an integral cleaning tape section is designed to accommodate the length of cleaning tape in a manner that is compatible with existing tape drive systems. In particular, the hub on the supply reel in the single reel magnetic tape cartridge is dimensioned to accept the length of cleaning tape such that the radial position of the End Of Tape hole in the magnetic tape media occurs in the same position as that of existing single reel magnetic tape cartridges that are not equipped with the length of cleaning tape appended to the magnetic tape media. This enables the cleaning tape equipped magnetic tape cartridge to be compatible with existing tape drive systems.

Abstract: A magnetic tape cartridge having an opening provided on one side wall of a cartridge case, a slide door slidably supported by a guide part disposed along the one side wall, the slide door for achieving a shutting-and-opening operation of the opening. A spring member impels the slide door to the shutting direction side, and is provided with a supported part. A spring supporting part retains the supported part. The spring member is retained by the spring supporting part through the supported part and impels the slide door to the shutting direction side.

Abstract: A brake slide assembly for securing a spool inside a data storage tape cartridge housing is disclosed. The brake slide assembly includes at least one brake slide and a flexible member. The brake slide(s) include a locking wedge, a brake button end, and a riser. The locking wedge is configured to selectively engage between the spool and an interior surface of the cartridge. The brake button end is configured to slidingly couple with a brake button of the cartridge. The riser extends between the locking wedge and the brake button end. In this regard, the flexible member is coupled to the brake slide(s).

Abstract: A reel has: a cylindrical hub, which is molded of a resin material, and around which a recording tape is wound; a pair of flanges provided at end portions of the hub, and holding transverse direction end portions of the recording tape; and a ring-shaped member formed of metal and disposed at an inner side of the hub, at least one portion of an outer peripheral surface of the ring-shaped member contacting an inner peripheral surface of the hub. The ring-shaped member of the reel contacts a substantially central portion, in a heightwise direction, of the inner peripheral surface of the hub.

Abstract: A tape cartridge housing allowing for both pre-shell closure and post-shell closure insertion of an auxiliary memory unit is provided. A flexible tape cartridge housing allows a manufacturer of tape cartridges to select whether to incorporate an auxiliary memory unit into the tape cartridge during the manufacturing process while a tape cartridge is still not fully assembled, during the end of the manufacturing process when the tape cartridge top and bottom shells have been combined, or after the manufacturing process when the tape cartridge is ready for operation.

Abstract: A metal plate of a recording tape cartridge is provided with a tapered portion at an outer circumference thereof. In a state in which the metal plate is attached at a fixed-side mold plate of a metal mold for molding a reel hub and a lower flange, a gap is formed between the tapered portion and the fixed-side mold plate. During molding, molding material flows into the gap. Because of this gap, an annular pawl portion is formed at the reel hub, which annular pawl portion integrally joins the metal plate with the reel hub by sandwiching the metal plate via the tapered portion.

Abstract: A magnetic tape cartridge has a case including a datum hole into which a positioning pin is inserted at a predetermined position thereof; a reel rotatably supported on the case with a magnetic tape wound thereon and including an engaging gear formed in the outer periphery of the flange thereof; a rotation restricting mechanism disposed in the case and engaging with the engaging gear of the reel to thereby restrict the rotation of the reel; and, an engagement releasing element slidably inserted into the datum hole from inside the case and removing the engagement between the rotation restricting mechanism and the engaging gear through the sliding movement thereof within the datum hole, wherein the positioning pin is inserted into the datum hole from outside of the case and push and slide the engagement releasing element, thereby releasing the rotation restriction of the reel by the rotation restricting mechanism.

Abstract: A tape reel in which molding quality of a flange unit is improved so as to improve reliability at the time when a magnetic tape runs at high speed, and a tape cartridge having the same. A plurality of reference planes (152v) formed between a chucking gear (152b) and an outer peripheral rib (152r2) formed at an outer peripheral side of this chucking gear (152b) are provided separately from the outer peripheral rib (152r2). And the reference plane (152v) is formed with edge planes of each of a first rib (152v1) extending toward a circumference and a second rib (152v2) extending toward a direction crossing the first rib (152v1). According to this arrangement, a volume at a portion constituting the reference plane (152v) is made smaller, occurrence of a sink after a resin is hardened is suppressed, and molding quality of the flange unit (152) is improved so that straight runnability of the magnetic tape at high speed running and reliability in recording/reproducing operation are improved.

Abstract: A case of a recording tape cartridge, which accommodates a reel on which a recording tape is wound, has a substantially rectangular opening at a rear end wall which is at a rear side in a direction of loading the recording tape cartridge into a drive device. A block, which is equipped with a memory on which various types of information such as a recording capacity and the like are stored, is fit into and mounted to the opening. The memory is mounted to the block so as to be inclined at substantially 45° with respect to a rear surface and a bottom surface of the case. The block can be attached to and removed from the case. Access to the memory in order to read and write information from and onto the memory is possible from the rear and from beneath.

Abstract: A magnetic tape cartridge which includes a single tape reel on which magnetic tape is wound on the outer peripheral surface of a reel hub thereof, rotatably housed in the inside of a cartridge case; and a reel lock member for inhibiting the rotation of the tape reel, provided movably in an axial direction of the tape reel between a lock position and a lock release position, in the inside of the reel hub; wherein a position restriction rib opposed to the outer periphery of the reel lock member for restricting an axial deviation of the reel lock member from the axial position of the tape reel is formed discontinuously with the inner peripheral surface of the reel hub on the top surface of the bottom of the reel hub in the inside of the reel hub.

Abstract: A recording tape cartridge has a reel at whose axially central portion is provided a reel hub which is shaped as a cylindrical tube having a bottom and around whose outer peripheral surface a recording tape is wound; an engaging gear provided within the reel hub; a case rotatably accommodating the reel; and a braking member having a braking gear which can mesh with the engaging gear. The engaging gear is formed in a form of internal teeth or in a form of external teeth. A tooth surface of each tooth is substantially parallel to an axis of the reel hub. The braking member is supported so as to be unable to rotate with respect to the case, and moves along an axis of the reel, and can be disposed at a rotation locking position, at which the braking gear meshes with the engaging gear, and a released position at which meshing is released.

Abstract: A gripped part structure of recording tape cartridges of different types housed in a same library, with each recording tape cartridge including a case housing therein recording tape, and two gripped parts that are gripped by a gripping mechanism of the library, wherein the gripped parts are formed in the case, and a distance from a side wall of the case facing the gripping mechanism of the library to the gripped parts, a height of the gripped parts in a thickness direction of the recording tape cartridge is identical for each recording tape cartridge regardless of the type of recording tape cartridge, and a distance between the gripped parts cartridge is identical for each recording tape cartridge regardless of the type of recording tape cartridge.

Abstract: In order to provide a recording tape cartridge which always can be piled up stably while a region for a label can be secured, there is provided a recording tape cartridge comprising a case having a substantially boxed shape and rotatably accommodating a reel around which a recording tape is wound, a recessed portion formed on an upper surface of the case, and a stacking rib protrudingly provided manner on a lower surface of the case, for engaging with the recessed portion when a plurality of the recording tape cartridges is stacked, a protruding portion, which defines a label region, being formed at a position in the recessed portion, which position does not interfere with the stacking rib when the plurality of the recording tape cartridges is stacked.

Abstract: A recording tape cartridge which can be assuredly positioned in a drive device. A positioning cover bridges across and parallel to a mounting portion of a bucket of the drive device. Stoppers are provided at corner portions of the positioning cover that are positioned at a deeper side of the bucket. Angled surfaces, which are surface-contactable with the stoppers, are provided at a magnetic tape cartridge. The magnetic tape cartridge can be positioned in horizontal directions in the drive device by surface-contacting the angled surfaces with the stoppers. Consequently, reference holes for positioning the magnetic tape cartridge in horizontal directions in the bucket are not required.

Abstract: The self-centering tape reel for a single reel tape cartridge provides a magnetic tape reel that is equipped with one or more features to center the tape reel with respect to a rotatably driven feature, such as a drive chuck, in the tape drive that rotates the tape reel. The self-centering tape reel uses a chamfered ring that encircles the drive teeth formed on the tape reel that engage the drive chuck. The chamfered ring fits into a chamfer that is formed in the circumference of the spline access hole located in the bottom of the tape cartridge housing.

Abstract: A recording tape cartridge has: a case rotatably accommodating a reel on which a recording tape is wound; a reel area rib provided at an inner surface of the case, and defining a range in which the reel is accommodated; and a contact preventing mechanism which is provided at an inner surface of the case, is positioned in a reel hub forming the reel, and prevents contact between the reel area rib and the reel.

Abstract: A holder device for holding a recording paper roll includes a pair of holders. A first holder has a first fitting portion with an anti-slip device and a first engagement portion. The anti-slip device has two claw members for forward rotation symmetrically disposed each other with respect to a center of rotation of the recording paper roll, two claw members for backward rotation disposed likewise, and springs biasing each claw member to an engagement position. When the first holder rotates in a forward or backward direction, the claw members for forward rotation or for backward rotation move to the engagement positions, respectively, in order to prevent a slip of the recording paper roll. An edge of each claw member is tapered along an attachment direction of the recording paper for easy attachment.

Abstract: A recording tape cartridge has a reel accommodated within a case, an engaging portion provided at a floor portion of a reel hub; a braking member provided so as to be unable to rotate within the case, and approaching and moving away from the floor portion of the reel hub, and able to assume a rotation locked position at which the braking member engages with the engaging portion, and a rotation permitted position at which a state of engagement with the engaging portion is cancelled; and a releasing member disposed at an inner side of a guide wall portion provided at the floor portion of the reel hub, and when the reel is rotated, the releasing member holds the braking member at the rotation permitted position while abutting the braking member. The braking member has a tubular wall portion which overlaps with an outer side of the guide wall portion.

Abstract: A single reel with magnetic tape wound thereon is housed in a case. A restraining member, for restricting rotation of the reel by moving toward or away from the reel, is urged in a restraining direction by an urging member. The pushing-up portions of a releasing member are inserted into the through holes bored in the reel gear of the reel 2 so that the lower ends can abut a driving gear. The releasing member moves the restraining member in a releasing direction by moving according to the chucking operation of drive-side rotation drive means. In this manner, reel-rotation restraining means allows rotation of the reel when being used and restricts the rotation when not being used. In this construction, each of the through holes is bored between the tooth edges of the reel gear so that the releasing member can perform a reliable releasing operation.

Abstract: A magnetic tape cartridge is provided, in which the mating of the lower half and the upper half can be easily performed and which is applicable to automated assembly, when the magnetic tape cartridge having a sliding door is assembled. The rib projects from the upper section of the first guide wall in the direction of the opposite second guide wall. On the other hand, the groove, which faces the rib, is carved on the inner side surface of the sliding door. The rib engages with the groove, thereby restricting the vertical displacement of the sliding door. Also, the engagement of the rib and the groove guides the sliding door in the guide channel freely.

Abstract: A tape cartridge, for use with a tape drive having an actuation member, includes a cartridge body that is insertable into the tape drive and a door movably associated with the cartridge body. The door is engageable with the actuation member when the cartridge body is inserted into the tape drive, and is movable between a closed position and an open position upon engagement with the actuation member. Furthermore, the door includes a retainer that is enageable with the actuation member when the door is in the open position to facilitate retention of the cartridge body in the tape drive.

Abstract: A magnetic tape cartridge with an improved reel-rotation restraining mechanism is disclosed. The reel-rotation restraining mechanism has a reel locking member, which is movable toward and away from the reel, for restricting rotation thereof; an urging member for urging the reel locking member in a restraining direction; and an releasing member, which is rotatable integrally with the reel, for moving the reel locking member in an unlocking direction by moving according to a chucking operation of a rotation drive mechanism of a drive unit. The releasing member has three leg portions on the vertexes of a triangular plate portion insertable into through holes in the reel. The releasing member is sized so that with part of the releasing member inserted into a center opening of the reel, and two of the three leg portions positioned near the through holes, the remaining one leg portion can be dropped and inserted within the center opening.

Abstract: Tape is spooled onto a hub by receiving the tape between guide members. The guide members guide one or both edges of the tape as the tape begins to wrap around the hub and floats on a layer of air formed between the tape and a previously wound layer of the tape.

Abstract: A take-up or supply reel for aligning and stacking storage tape. The tape reel may include a hub, where tape wraps around the hub and two flanges. The flanges are spaced apart on the hub, where surfaces of the flanges face each other at a distance such that the tape may pass therebetween. At least one of the opposing surfaces includes a guiding portion where a separation distance between the opposing surfaces of the flanges corresponding to the guiding portion decreases as tape is wound to the hub. The guiding portion guides the tape as it passes therebetween to stack more uniformly on the hub.

Abstract: The present invention aim at providing a magnetic tape cartridge, which can be assembled using an automated products line by enabling the assembling operation of a spring member and a slide door with ease. For attaining these problems, there is provided a magnetic tape cartridge comprising a magnetic tape cartridge comprising; an opening provided on one side wall of a cartridge case, and is used for tape drawing; a slide door slidably supported by a guide part disposed along said one side wall, and said slide door is used for achieving the shutting-and-opening operation of said opening; a spring member for impelling said slide door to the shutting direction side, and is placed on said guide part; and a leading part for leading one end part of said spring member to a spring engaging part provided on said slide door, and is provided at one end part of said spring member.

Abstract: A recording tape cartridge is disclosed wherein when in non-use, a reel accommodated in a case and having a recording tape wound thereon is prevented from rotating by being meshed with a braking member which is non-rotatble with reference to the case; and when in use, in response to the braking member being pushed up by a release pad or a clutch member, the reel is released from the meshed state and allowed to rotate together with the release pad or the clutch member. With the rotation of the reel, the braking member has its pivot portion disposed in sliding contact with a sliding contact portion formed at a portion corresponding to an axial center of the release pad or the clutch member while being pressed against the sliding contact portion by a biasing force of a compression coil spring. The recording tape cartridge is designed such that a relation ?×L?0.

Abstract: A tape reel assembly for a data storage tape cartridge is described. The tape reel assembly has a hub. The hub includes a cylindrical core, an annular arm, and a web. The cylindrical core defines a drive side and a top side. The annular arm is co-axially disposed exterior to and separated from the cylindrical core. Additionally, the annular arm defines a tape winding surface bisected by a center line into a top half opposite the drive side and a bottom half adjacent the drive side. The web extends from the top side of the core, and a web center connects to the annular arm at a point in the top half.

Abstract: A recording tape cartridge in which a reel includes a reel gear and an engaging gear. The reel gear is formed in an annular shape at an outer face of a base portion of a reel hub. The engaging gear is formed in an annular shape at an inner face of the base portion. Magnetic tape is wound onto an outer periphery of the reel hub. A braking member is engaged with the engaging gear by an urging force and prevents the reel from rotating. A clutch member opposes a gear aperture at a radial direction inner side relative to the reel gear. An operationally pushed surface of the clutch member is pushed by a releasing surface of a drive device and the brake member is lifted, whereby rotation of the reel is enabled.

Abstract: A recording tape cartridge comprises: a case which is substantially rectangular, and at which an upper case and a lower case are joined together with peripheral walls thereof abutting one another, and which rotatably accommodates a single reel on which a recording tape is wound; and an opening formed at a corner portion of the case at a side of loading the case into a drive device, the opening being for pulling out of a leader member attached to an end portion of the recording tape. Concave portions, which extend over the upper case and the lower case and which are isosceles trapezoidal in plan view, are formed at a peripheral wall of the case at the side of loading the case into the drive device. In accordance with this structure, a peripheral wall, whose end portion is a free end due to an opening being formed, can be reinforced, and thereby a deterioration in strength of the peripheral wall can be prevented.

Abstract: Stackable rotary devices form a multi-position mechanical indicator for a portable data storage cartridge. Each rotary device is a right cylindrical section, and is separately rotatable in a chamber of the cartridge. A peripheral surface of the rotary device has an encoded pattern of 1) at least one cylindrical surface and at least one facet interrupting the cylindrical surface, or of 2) readable indicia, located at various angularly spaced rotational positions. At differing rotational positions of the rotary devices, at least one or none of the facets or readable indicia are positioned at an exterior wall opening of the cartridge chamber.

Abstract: In a recording tape cartridge, at a reel which is accommodated within a case, a magnetic tape is wound around an outer peripheral portion of a reel hub, and a reel gear is provided coaxially and annularly at an end surface of the reel hub. An annular convex portion projects coaxially from the end surface of the reel hub. An end surface of the annular convex portion is a reference surface which is orthogonal to an axis of the reel. When the magnetic tape is used, the reference surface abuts a positioning surface of a drive device, the reel is positioned in an axial direction, and the reel rises up within the case. The reel rotates around the axis due to driving force of a driving gear which meshes with the reel gear.

Abstract: A recording tape cartridge has: a case which is substantially rectangular and which rotatably accommodates a single reel on which a recording tape is wound; an opening for pulling-out of the recording tape, the opening being formed in a wall surface of the case at a side of loading into a drive device other than at a corner portion of the case; a leader block fixed to an end portion of the recording tape, and pulled-out by a pull-out member of the drive device, and able to close the opening; and a position restricting portion disposing the leader block at an inner side of the wall surface and parallel to the wall surface.

Abstract: A tape unit has a support including a rotation support section rotatably supporting a tape spool and facing a roll part of a print tape, and a junction section extending from the rotation support section. A guide groove for guiding the print tape pulled out from the roll part is formed on the junction section. By virtue of such composition, the tape unit can be attached to a cassette case body of a tape cassette maintaining the print tape in the guide groove, by which the replacement of the tape unit which is stored in the cassette case body can be made easier.

Abstract: A recording tape cartridge in which melting, abrasion or the like does not occur at a portion of abutting of a brake member with a release member, or with a release portion of a drive device, during rotation of a reel. In this recording tape cartridge, a magnetic tape is wound onto the reel at a reel hub inside a case. A brake member is non-rotatably provided inside the case. The reel is rotation-locked when the brake member is disposed at a rotation-locking position, at which the brake member engages with an engaging protrusion of a bottom portion. A release pad is disposed between the bottom portion and the brake member and abuts against both thereof. When the release pad holds the brake member at a rotation-enabling position, the reel is rotatable.

Abstract: A magnetic tape cartridge made up of a cartridge case composed of an upper and lower cases welded together on the mating surfaces by ultrasonic welding with a plurality of energy directors, and a single reel of magnetic tape rotatalby retained in the case, in which the weld deposits formed by the energy directors may be prevented from sticking out of the mating surfaces. A plurality of energy directors provided on one of the mating surfaces have an elongated shape, and are disposed with the longitudinal direction substantially perpendicular to the direction along the side wall of the upper and lower cases.

Abstract: A magnetic tape cartridge is constructed by rotatably housing a reel having magnetic tape wound therearound within a cartridge case. The cartridge case is constructed by an upper case and a lower case. The cartridge case has a tape extraction opening in a side wall thereof. The upper case and the lower case are fixed by welding at an abutment surface P, where the upper case and the lower case abut each other. In addition, vertically extending ribs that alternately extend up and down beyond the abutment surface P are provided on the inner surfaces of the side walls of the upper case and the lower case in the vicinity of the opening. By this construction, the strength of the cartridge case in the vicinity of the opening is improved, thereby preventing damage thereto even when the magnetic tape cartridge is dropped or the like.

Abstract: In a region more on the back surface side than on the front surface of the circumferential side surface of a magnetic plate, a circumferential projection having an outer diameter larger than that on the front surface side is formed, and the magnetic plate is fitted to a circular reel portion so as to be embedded in the circular reel portion at the circumferential projection thereof.

Abstract: A magnetic tape cartridge includes a cartridge case consisting of an upper half and lower half; a magnetic tape pulling-out port formed at a corner of side wall of the cartridge case, a curved door opening/closing the tape pulling-out port, a guide groove guiding the door to universally slide in its opening/closing directions, a door-side spring hooking portion protrusively provided with the door, a case-side spring hooking portion formed in an inner surface of the cartridge case, a tensile coil spring, of which one end of the coil spring is hooked in the door-side spring hooking portion and the other end of the coil spring is hooked in the case-side spring hooking portion, energizing the door to a closing position of the tape pulling-out port, and a spring putting platform provided neighboring the door-side spring hooking portion, and for receiving the tensile coil spring in a state in which the tensile coil spring is temporarily assembled on the door side spring hooking portion.

Abstract: A recording tape cartridge in which it is possible to suppress radial direction movement of a reel by a braking member which impedes rotation of the reel at a time when the recording tape cartridge is not being used, while ensuring strength of a reel hub with respect to pressure of winding of a recording tape therearound. At the recording tape cartridge, the reel, around which a magnetic tape is wound and which is accommodated in a case, is set in a rotation locked state when a braking member, which cannot rotate due to the braking member engaging with a cross-shaped rib, engages with anchor projections. When the braking member moves apart from the anchor projections, a meshed state is cancelled, and the reel can rotate with respect to the case. A reinforcing ring, which is fit together with an inner peripheral surface of the reel hub, reinforces the reel hub whose top end is open.