KR900010126Y1 - Magnetic tape cassette equipment - Google Patents

Abstract

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Description

Magnetic Tape Cassette Device

1 is a perspective view of a magnetic tape cassette of the present invention in which the front cover and the sliding plate are closed.

FIG. 2 is a cassette bottom cross-sectional perspective view of FIG. 1 with the front cover and sliding plate in an open position.

3 is an enlarged sectional view of the sliding plate latched in the closed position taken along line III-III of FIG.

4 is a view of the sliding plate at the same position as FIG. 3 taken along IV-IV of FIG.

FIG. 5 is a cross-sectional view of the operating portion of the latching member which is lifted by the latch release means of the magnetic tape cassette device cut along the line IV-IV of FIG.

6 is a sectional view of a sliding plate which is latched in the open position by the latching portion of the latching member cut along the line II-II of FIG.

7 is a bottom partial perspective view of another embodiment of the magnetic tape cassette of the present invention with the front cover and sliding plate in the open position.

FIG. 8 is an enlarged cross-sectional view of the sliding plate latched in the open position cut along the line VII-VII of FIG. 7. FIG.

* Explanation of symbols for main parts of the drawings

1 housing 2 first basic wall

3: second basic wall 4: opening

8: partitioning 9: sliding plate

13: projection 19: passage

20: front cover 22: side flange

23: stop plate 27: latching unit

30: operating part 31: groove

The present invention relates to a magnetic tape cassette device suitable for cooperating with a magnetic tape cassette. In the apparatus according to the present invention, the slide plate of the cassette is latched in a closed position by at least one latching member having a latching portion and an actuating portion, and the main portion of the slide plate is from the front edge of the main portion of the slide plate. A slot or groove extending rearward, the actuating portion being arranged to protrude into a slot or groove proximate the rear edge in the closed position of the sliding plate, the mounting device of the device having an unlatching member, The latching member is characterized in that it is introduced and passed through the slot or groove of the main part of the sliding plate during insertion of the cassette into the mounting apparatus for operating the latching member operation. During insertion of the cassette, the unlatching member introduces a slot or groove into the slide plate to effectively unlatch the slide plate so that the slide plate can be moved from the closed position to the open position.

Magnetic tape cassettes are described in the specification of US Pat. No. 4,235,395 (PHN 9121). The known cassette, the V-2000 cassette, has a front opening covered at the front by the front cover and covered by the sliding plate at the side walls of the two base walls. In the closed position of the front cover and sliding plate, the cassette can be protected against dust penetration and mechanical damage. The damage is to damage the tight portion of the magnetic tape extending across the front opening. In the closed position, the slide plate consists of a latch for the front cover so that it is not improperly opened while the user is using the cassette. However, since the slide plate can be freely displaced backward in the closed position, the front cover can be suddenly shaken open by the user after the slide plate slides backward, so that the magnetic tape portion extending across the front opening is damaged. You can get It can also penetrate dust or inside the cassette housing. Because in certain situations, the interior of a known cassette cannot be completely sealed at the opening position in the two base walls.

It is an object of the present invention to provide a cassette which completely closes the cassette and enables the parts used to close the cassette to be effectively latched in the closed position.

In the present invention for this purpose, there is no opening over the entire area of the second base wall, the main part of the front cover is adjacent to the base wall in the closed position of the cover, and the main part of the sliding plate slides to cover the opening. Extending rearward beyond the spindle opening in the first base wall in the closed position of the plate and having two openings exposing the opening when the slide plate is in the open position, the slide plate having at least one having a latching and actuating portion; Latched in the closed position by the latching member, the main part of the slide plate being provided with a slot or groove extending rearward from the main part front edge of the slide plate, the working projection being a slot proximate the rear edge in the closed position of the slide plate. Or it is arranged to protrude into the groove.

As a result, a cassette is always provided which is sufficiently closed at the side of the second base wall and can be closed by the sliding plate at the side of the first base wall. The slide plate may be latched by a latching member, which latches the front cover through the slide plate. The separated latching and actuating parts of the latching member can move more freely than the structure of the unlatching means on the magnetic tape device. Slots or grooves in the main part of the sliding plate provide the advantage that the unlatching means can actuate the actuating part through sliding motion so that the cassette can be inserted into the device. The shape of the latching portion makes it suitable for the latching action and allows the sliding plate to be sufficiently latched.

In practice, the actuation portion along with the slot or groove substantially prevents accidental opening of the slide plate and front cover. The slide plate can only be unlatched by the unlatching means in the magnetic tape cassette device. When using the cassette in the open position, the slide plate does not occupy any additional space in the magnetic tape cassette device.

The magnetic tape cassette device of the present invention is suitable for use in magnetic audio, video and data recorders. Therefore, the structure conforming to the present invention can be usefully used for small cassettes. In particular, the present invention is suitable for magnetic tape cassettes for digital audio recording, in which magnetic tapes are drawn out from the cassettes and wound around a rotating drum.

In a suitable embodiment of the present invention, the latching and actuating portions are located near the free ends of the resilient arms and the arms are connected to the first base wall at the other end and the free ends of the arms are planar of the first base wall. There is a feature that moves almost vertically. This allows the sliding plate to be effectively latched by the latching member means. Further, the unlatching means of the magnetic tape cassette device can move the latching portion out of the latched position by floating the operating portion against the spring force.

The resilient arm allows for the selection of the length and thickness of the arm or for local compression or the use of concave portions within the arm to determine the spring force acting on the latching portion.

In another suitable embodiment of the present invention, the latching, actuating and resilient arms are characterized by forming an integrated unit with the first base wall. Thus, the latching member is configured with the first basic wall to minimize the number of separated parts used in the cassette structure of the present invention.

In another suitable embodiment of the present invention, the operating portion is rounded or pyramid shaped, the latching portion is rectangular, and the operating portion is positioned adjacent to the latching portion in a direction transverse to the moving direction of the sliding plate. The contour of the actuating portion facilitates smooth cooperation between the actuating portion on the device and the unlatching means such that the shape of the adjacent latching portion is particularly suitable for latching operation.

The latching portion is in the closed position of the slide plate, and the latching portion has the advantage of being able to cooperate with the hole wall in the inner surface of the slide plate to latch the slide plate in the closed position.

In another suitable embodiment of the present invention, the front cover has a recess in the main edge, and when the front cover is in the closed position, the recess is arranged in line with the slot or groove in the main portion of the sliding plate. have.

When the magnetic tape cassette is inserted into the device by sliding movement, the unlatching means can be inserted into slots or grooves in the main part of the sliding plate, which has the advantage of unlatching the plate without obstruction by the front cover.

If the slide plate has a lateral portion adjacent to the main part and is located in one adjacent side wall of the housing and each guided to a groove in the adjacent side wall, the slide plate can be guided safely.

The groove also connects the sliding plate to the housing of the cassette in an effective manner. In this respect, another suitable embodiment is characterized in that, in the closed position of the sliding plate, the side portion cooperates with the lateral flange of the front cover to latch the cover to the closed position. By allowing the side of the slide plate to latch on the front cover, it is not necessary to use other parts specifically for this purpose.

Hereinafter, with reference to the accompanying drawings will be described in detail two embodiments of the present invention.

The magnetic tape cassettes shown in FIGS. 1 and 2 have parallel and substantially rectangular base walls, namely a first base wall 2 (FIG. 2) and a second base buck 3 (FIG. 3). The housing 1 is provided. The base wall 2 constitutes the lower wall of the housing and consists of two circular spindle openings 4 in which the terminal (only the right opening) is shown in FIG. 2. The other base wall 3 has no circular spindle opening. The cassette housing 1 has two side walls 5 and a rear wall 6 and has an opening 7 in the front which extends from the bottom into the first base wall 2 and on the diaphragm 8. It is separated from the inside of the housing 1. The sliding plate 9 can slide on the first base wall 2 and has a main part 10 and two lateral parts 11, the main part being parallel to the plane of the base wall with respect to the first base wall. Located in the plane, the two side parts 11 are connected to the main part and located adjacent to each side wall 5. Each side portion 11 has a ridge portion 11a therein, which allows the ridge portion 11a to slide in the outer groove 12 of the adjacent side wall 5 to the sliding plate 9. The slide plate is connected to the housing 1 at the same time. Thus, the sliding plate has a closed position indicated by a solid line in FIG. 2 covering the front opening of the cassette housing at the bottom and a point where the front opening is exposed at the bottom so that the tape ejecting means of the tape cassette device (not shown) can be drawn into the opening. It may slide relative to the cassette housing between the open positions indicated by the dashed lines. The slide plate 9 has a projection 13 therein. The protrusion can slide in a slot (not shown) of the first base wall 2 in a direction perpendicular to the rear wall 6, one end of the tension spring 14 being connected to the protrusion and the other end of the protrusion Fixed in the interior of the primary wall 2, the tension spring 14 constitutes a resilient means, which directs the sliding plate 9 to the closed position.

The main part 10 of the sliding plate 9 has two openings 15 which are coaxial with the opening 4 in the base wall 2 in the open position of the sliding plate (FIG. 2). Allows the drive spindle, not shown, of the magnetic tape cassette device to be drawn into the cassette housing through the opening 4.

In the interior of the housing 1 two reel hubs 16, 17 are supported between the base walls 2 and 3 so that they can rotate relative to the side extending perpendicular to the base wall. The magnetic tape 18 is wound around the reel hub, and the tape portion 18a extends taut across the front opening 7. The partition 8 is formed by a convex tape guide 8a having a cylindrical curve at both ends, the left tape guide of which can be seen in FIG. A portion of each tape guide 8a and adjacent sidewall 5 is adjacent to passage 19 at the front end, through which magnetic tape 8 extends the front opening 7 from the interior of housing 1. Stretched across). When the cassette is not used, i.e. when the cassette is not inserted into the magnetic tape cassette device, the front opening 7 and the magnetic tape portion 18a and the two passages 19 extending across the opening have a front cover. All are covered from the front by 20, and the cover has a main portion 21 and two side flanges 22 at both ends. The side flange 22 is pivotally connected to each side wall 5 of the housing by a pivot pin 22a.

As shown in FIG. 1, the main portion 21 of the front cover has a flange or lip 21a along the upper edge, and when the cover is closed the upper edge is actually in line with the second base wall 3 of the housing 1. Adjacent and have the same plane. Similarly, when the front cover is closed, the lateral flanges 22 of the front cover are actually adjacent to the rear portion 11 of the sliding plate 9 and have the same plane. Thus, the magnetic tape cassette is closed correctly.

The stop plate 23, located inside the housing 1 and adjacent to the base wall 3, can be moved in a plane parallel to the plane of the base wall 3 and supported by a spring 24 supported by a diaphragm 8. It is compressed by the barrier 6. When the stop plate 23 is not used, the stop plate 23 prevents the reel hub from rotating against the peripheral surface of the reel hubs 16 and 17 under the influence of the spring 24 and the tape 18 is cassette. The tension is maintained across the front opening 7 of the housing. The stop plate 23 extends from side to side across the cassette housing adjacent to the wall having a vertical side portion 25 provided with a protrusion 26 so that the protrusion is a slot in an adjacent side wall 5 (not shown). Not stretched). The protrusion 26 can slide in the slot and is covered by the side portions 11 of the slide plate 9 in the closed position of the slide plate. Thus, when the slide plate 9 is closed, the protrusion 26 is not activated. However, when the slide plate slides back to the open position indicated by the solid line in Fig. 2, the protrusions 26 are exposed and operated together with the pivot pins 22a of the lateral protrusions 22 of the front cover 20 so that the front cover is closed. The stop plate 23 is moved forward by the flange 22 when the 20 is turned to the open position.

Thus, the stop plate 23 is released from the reel hubs 16 and 17 when the front cover 20 swings open.

As shown in FIG. 1, in the closed position of the slide plate 9, the ridge portion 11b of each side portion 11 of the slide plate is formed at the edge portion of the adjacent side flange 22 of the front cover 20. Adjacent to 22b), the front cover is latched in the closed position.

When the slide plate 9 is directed to the open position shown in solid line in FIG. 2 and slides backward, the side portion 11 of the plate moves backwards and pivots the side flanges to unlatch the front cover. Allow it to swing and open.

In the first basic wall 2 two latching members 27 are arranged, only the right latching member is shown in FIG. 2.

The latching member 27 extends perpendicular to the plane that is perpendicular to the base wall 2 and includes the rotational axis of reel hubs 16, 17, and is mirrored relative to the plane that is equidistant from the reel hubs 16, 17. Arranged in a symmetrical relationship. The latching member 27 is formed together with the base wall 2 and is positioned over a short distance from the opening 34 associated with the base wall to behind the passage 29 adjacent the side wall in the opening 34 associated with the base wall 5. do. Each latching member 27 has a resilient arm 28 which lies in the plane of the base wall 2 and extends in the direction of movement of the slide plate 9.

The arm is connected to the base wall 2 at the rear edge and forms a latching portion 29 (FIG. 3) and an actuating portion 30 (FIG. 4) at the front edge, the latching portion and the actuating portion as one protrusion. It is arranged in parallel on the arm 28 and projects from the plane of the first base wall 2 on the outer (lower) side, as shown in FIGS. 3 and 4, respectively. As shown in FIG. 3, in the closed position of the sliding plate 9, the latching portion 29 of each latching member is terminated in the associated groove formed by the groove 31 of the inner surface of the sliding plate 9. In cooperation with the wall 31a, the groove 31 extends perpendicular to the rear wall 6 to latch the slide plate 9 in the closed position. In the open position of the slide plate 9, the latching portion 29 cooperates with the front edge 10a of the main portion 10 of the slide plate 9 to securely latch in this position, as shown in FIG. 6. Therefore, the front and rear surfaces of the latching portion 29 of each latching member, that is, the surface cooperating with the sliding plate, extend perpendicular to the parallel surface of the sliding plate and the base wall 2, and the latching portion should be rectangular as appropriate. In the closed position of the slide plate 9, the actuating portion 30 of each latching member 27 protrudes into an associated slot 32 in the main portion 10 of the slide plate 9. The slot 32 extends rearward from the front edge of the plate 9 and the actuating portion 30 is located near the rear edge of the slot in the closed position of the plate.

When the cassette slides into and inserts into the magnetic tape cassette device, each slot 32 receives an unlatching member provided in the device. The unlatching member may for example be a pin 33.

As the cassette moves forward, each actuating portion 30 engages and slides with the member to be lifted by the member, and the actuating portion 30 has a circular contour, which can slide smoothly on the unlatching member. . The latching of the resilient arm 28 of the latching member 27 directs the member out of the groove of the sliding plate 9 to unlatch the pin. The spring force of the arm 28 can be determined by selecting the length and thickness of the arm.

In addition, the use of the arm 28, the latching portion 29 and the actuating portion 30 makes use of additional parts necessary for latching the slide plate 9 to no avail.

As described above, when the magnetic tape cassette device is not used, the slide plate 9 is in the closed position and covers the opening 4 in the lower wall 21 of the cassette housing.

The plate covers the front opening 7 of the housing at the bottom such that the tape portion 18a of the magnetic tape 18 is inaccessible from the bottom of the cassette housing. At the front, the tape portion 18a is covered by the main part 21 of the closed front cover 20, while on the upper side the upper flange or lip 21 of the front cover 20 and the base wall 3 of the cassette housing. Contact between them provides effective shielding. When the latching member 27 is in the position shown in FIG. 3, the latching member 27 prevents the sliding plate 9 from moving. When the cassette 29 is not in the magnetic tape cassette device, the unlatching of the sliding plate 9 is very difficult. This is because the equipment of the two latching members and the actuator 30 are located in a relatively narrow slot 32, which makes it difficult to press the actuator with a finger or a fingernail. Therefore, the cassette according to the present invention is good for preventing accidental opening of the sliding plate 9. Latching of the slide plate also causes the front cover 20 to latch, so that the front cover cannot be accidentally opened. Latching the front cover and the sliding plate has the advantage that the stop plate 23 does not operate accidentally, and therefore the reel hub does not rotate when rotation is not required.

When the slide plate 9 and the front cover 20 are closed, the magnetic tape cassette of the present invention forms a completely closed unit to prevent mechanical influences damaging the magnetic tape of the cassette and to effectively infiltrate dust and contaminants. Shield. The magnetic tape portion 18a must be securely protected since the cassette is exposed when not in use.

As described above, when the cassette is inserted into the magnetic tape device, recording or reading is possible by the rotating magnetic head in the head drum when the tape ejecting means of the device draws the tape 18 and advances around the head drum of the device. The magnetic tape portion needs to be exposed at the front opening 7 of the cassette housing. The device working with the rotating head drum may be a video record. Another example of this is an audio or data recorder using digital recording and reproduction signals. The latter type of recorder requires a relatively small length of magnetic tape. The cassette of the present invention is particularly suitable for this purpose. Because the parts used are very small.

In order to mount a cassette in a magnetic tape cassette device, it is necessary to insert the cassette into a mounting mechanism in the device. In this case the device may be provided with a so-called "letter box" which is open from the front. During the insertion of the cassette, the unlatching member of the apparatus, which can be stably arranged in the mounting mechanism, passes through the recess 21b in the lower edge of the main portion 21 of the front lid 20 of the cassette (FIG. 1). The recessed portion 21b is arranged in line with the slot 32 when the front cover is brought into the closed position in the slide plate 9 of the slide plate 9. Instead of the pin 33, the unlatching member may have a ridge at the bottom of the mounting mechanism into which the cassette is inserted. As shown in FIG. 5 and described above, during insertion of the unlatching member of the apparatus, the latching member is lifted by floating the actuating portion 30 of the latching member 27 against the spring force of the arm 28. For this purpose, the arm is deflected to release the latching protrusion 29 from the groove 31 of the sliding plate 9.

As a result, the arm is inclined to release the latching protrusion from the groove 31 of the sliding plate 9 to unlatch the plate. Therefore, when the cassette is inserted adjacent to the rear end wall of the slot 31 in the plate 9, the sliding plate 9 is fixed rearward by the unlatching member 33 so that the cassette housing ( The lower part of the front opening 7 of 1) is exposed. During the movement the spring 14 is again taut. When the unlatching member passes through the front edge 10a of the main portion 10 of the sliding plate 9, the latching portion 29 is formed at the edge 10a by the influence of the spring force of the arm 28 of the latching member 27. ) Snap to the position shown in FIG. In this position, the two latching portions 29 allow the slide plate 9 to be accurately positioned and latched in this position. When the slide plate is in the open position, the unlatching member can no longer be mounted and can be withdrawn from the cassette operating position. In the final position the sliding plate joins with the floating part of the first base wall 2 which is a short distance from the rear wall 6. In this position, the opening 15 approaches the opening 4 in the first base wall 2. Thus, the drive spindle of the magnetic tape cassette device can be easily engaged in the reel hub, or the cassette can be lowered by the mounting mechanism on the drive spindle.

As described above, the front opening 20 is unlatched by the rearward movement of the sliding plate. As a result of the downward movement of the mounting mechanism of the device, the front cover is opened by shaking in a known manner in the position shown in FIG. 2 and the stop plate 23 is the side flange 22 of the front cover against the force of the spring 24. Move forward, release the reel hubs (16, 17). In this example, a tape pivot pin or similar means protruding into the front opening 7 of the cassette housing can draw the loop of magnetic tape 18 out of the cassette and wind it around the head drum. Therefore, it is possible to record on the tape or to reproduce the record from the tape 18.

When the cassette is withdrawn from the apparatus, the actuating portion 30 of the latching member 27 is lifted again by the unlatching member 33 of the apparatus so that the latching portion 29 is in front of the main portion 10 of the sliding plate 9. Loosen from the edge 10a to unlatch the sliding plate.

Thus, the spring 14 returns the slide plate to the position shown in FIGS. 3 and 4, in which the slide plate is automatically latched by the latching portion 29. Prior to the return of the sliding plate 9 to the closed position, the front cover 20 returns to the closed position under the influence of the weight and the force and weight exerted on the stop plate 23 by the spring 24. When the slide plate is returned to the closed position, the front cover 20 is latched back to the closed position by the side portion 11 of the slide plate 9.

The second embodiment shown in Figs. 7 and 8 has many parts already shown in the first embodiment and denoted by the same reference numerals. In the second embodiment the two latching members 35 have a resilient arm 36, which arm has a rectangular latching portion 37 and an actuating portion 38, the actuating portion latching member 37. It is located in the shape of a pyramid. In the closed position of the sliding plate 39, the latching portion 37 joins the wall of the inner surface groove 40 of the plate 39 to latch the plate 39. The actuating portion 38 protrudes into the associated groove 41 in the plate 39, which extends in the same direction as the slot 32 in the first embodiment. The groove 40 is located in the bottom wall of the groove 41 and the other hole 42 in the bottom wall is located near the front edge of the sliding plate 39. In the open position of the plate 39, the latching portion 37 joins to the wall of the hole 42 to latch the plate. The side wall of the groove 41 is tunneled toward the main portion of the front cover 20, and the main portion 21 is provided with a concave portion 21b arranged in line with the groove 41. During insertion of the cassette as shown in FIGS. 7 and 8, the groove 41 receives the unlatching member 33 of the device. Each member raises the actuating part 38, which is located in the groove 41 adjacent the hole 40. At the same time, pins (not shown) on the device join the front edge of the plate 39 to direct the plate to the rear wall. By this force, the pyramidal portion 38 can slide smoothly at the edge of the hole 40 and the arm 36 is deflected until the portion 38 is released from the wall of the hole 40.

Thus, the slide plate 39 is unlatched from the latching member 35.

When the cassette is inserted, the inside of the plate 39 is at the top of the pyramidal portion 38 until the pyramidal portions 37 and 38 snap into the holes 42 under the influence of the spring force of the arm 36. Slide

In the position of the plate 39 shown in FIG. 7, the latching portion 37 allows the slide plate 39 to be accurately positioned and latched.

When the cassette is withdrawn from the device, each actuating portion 38 is lifted again by the unlatching member 33 of the device so that the pyramidal portions 37 and 38 are released from the wall of the hole 42 and the plate 39 ). The spring 14 then returns the plate 39 back to the position shown in FIG. 8 and the plate 39 automatically latches when the portions 37 and 38 snap into the hole 40 in that position. To be. Since the actuating portion 38 is arranged in a relatively narrow groove 41 and the portion 38 does not extend on the plane of the sliding plate 39, it is difficult to press the actuating portion with fingers or nails so that when no cassette is present in the apparatus Unlatching the sliding plate 39 is very difficult. Therefore, the embodiment of the present invention can reliably prevent the sliding plate 39 from being opened accidentally.

In a variant embodiment not shown, only one latching member 27 or 35 is used instead of two latching members 27 or 35. It is also possible to latch the sliding plate to the closed position using the latching portion 29 or 37 of each latching member. The slide plate can be fixed in the open position by the unlatching member of the magnetic tape cassette device. Further, as described in connection with the second embodiment of FIGS. 7 and 8, the slide plate can be fixed in the open position by pins, which pins direct the slide plate to the rear wall when the cassette is inserted.

Claims (5)

First and second base walls 2,3 and two side walls 5 parallel to each other, a rear wall 6, a front opening 7 extending rearward to the second base wall, and two reels A housing (1) having hubs (16, 17), wherein the first base wall (2) has two spindle openings (4) through which the drive spindles of the magnetic tape cassette device are connected to the reel hub. By way of example, a magnetic tape 18 is wound around the reel hubs 16, 17, extending from the tape portion 18a across the front opening 7, and moving between the closed and open positions and having a main portion ( And a front cover 20 comprising a front cover 20, wherein the main portion 21 has a front opening 7 in a closed position of the front cover 20 and a magnetic tape portion extending across the front opening. 18a) and lateral flanges 22 adjacent the respective sidewalls 5 of the housing 1 and pivotally connected to said sidewalls. A sliding plate (9,39) located outside the housing (1) and having a main portion (10) adjacent to the first base wall (2) of the housing; The sliding plate is guided so that the sliding plate latches the front cover 20 in the closed position, and also the front opening 7 in which the main portion 10 of the sliding plates 9 and 39 extends rearward to the first base wall 2. In the covering closed position, the housing is unlatched to operate in parallel with the first base wall towards the rear wall in an open position that allows the device and the tape ejecting means to adjoin the front opening 7 for the passage through. The slide tape guides the image, the sliding plates 9 and 39 move from the closed position to the open position when the cassette is inserted into the mounting apparatus of the apparatus, and the magnetic tape cassette moves from the open position to the closed position when the cassette is withdrawn from the mounting apparatus. Magnetic tape suitable to cooperate with In the cassette device, the slide plates 9 and 39 of the cassette are in a closed position by at least one latching member 27 and 35 having latching portions 29 and 37 and actuating portions 30 and 38. The main part 10 of the sliding plate 9, 39 has a slot or a groove 32, 41 extending rearward from the front edge of the main part of the sliding plate, and the actuating parts 30, 38 have a sliding plate. (9,39) are arranged to protrude into slots or grooves (32, 41) proximate the rear edge in the closed position, the mounting device of the device having an unlatching member (33), the unlatching member Through the slots or grooves 32, 41 of the main portion 10 of the sliding plates 9, 39 while inserting the cassette into the mounting apparatus for operating the actuating portions 30, 38 of the latching members 27, 35. A magnetic tape cassette device characterized by being drawn in and passing through. 2. The unlatching member (33) according to claim 1, wherein the unlatching member (33) has inclined front and rear edges, and while the sliding plates (9, 39) are inserted in the closed position, the front edge is in contact with the actuating portions (30, 38). And the rear edge is in contact with the actuating portion (30,38) while the sliding plates (9,39) are withdrawn in the open position. The magnetic tape cassette device according to claim 1 or 2, wherein the unlatching member (33) has an unlatching protrusion which is stably disposed on the lower portion of the mounting apparatus. 4. The magnetic tape cassette device according to claim 3, wherein the unlatching member (33) has an unlatching ridge portion disposed on a lower portion of the mounting position. 3. The mounting device according to claim 1 or 2, wherein the mounting device is close to the front edge 10a of the main part 10 of the sliding plates 9 and 39 after unlatching and the rear wall 6 holds the sliding plate during insertion of the cassette. Magnetic tape cassette device characterized in that it is directed to.