GB2051455A - Tape cassette loading/ejecting - Google Patents

Abstract

In a magnetic tape cassette transport mechanism, a cassette holder 6, 7 performs a cassette loading movement by first moving inwardly perpendicularly to the reel axes and then moving downwardly parallel to said axes. Manual insertion of a cassette C into holder 6, 7 move the latter inwardly thereby closing a switch 40, 42 to energise a tape drive motor 9 which also rotates a part-toothed gear 23, Fig. 10, so that a pin 22 thereon draws an entrainment slide 14, and thus holder 6, 7, inwardly until pins 34, on three-armed lever 33 linking slide 14 to holder 6, 7, reach the inner end of slot 35, continued inward movement of slide 14 then causing lever 33 to rotate about pins 34 to lower holder 6, 7 to the operative position, whereafter slide 14 is caused to move further inward to a position locked by latch 45 (Figs. 5, 6, 7) engaging pin 15 on slide 14; such further movement of slide 14 may be used to derive automatically any other desired control of the apparatus. In the locked position, pin 22 on gear 23 is engaged by a member 30 to hold the non-toothed part of gear 23 opposite motor 9 driven gear 24 (Fig. 11). On manual or automatic de-energisation of a solenoid 48 (Figs. 5-7), a spring 50 causes a member 47 to lift latch 45 so that a spring 51 can then return slide 14 and holder 6, 7 to the loading position. Toward the end of the return stroke of slide 14, a pin 32 thereon moves member 30 away from pin 22 so that a spring 29 (Fig. 11), acting on an edge of a flat facet of a member 28 integral with gear 23, rotates the gear 23 back into mesh with gear 24, motor 9 having been stopped when switch 40, 42 opens during return of holder 6, 7. <IMAGE>

Description

SPECIFICATION Tape cassette transport mechanism The present invention relates to an apparatus for reproducing and/or recording magnetic tapes in cassettes, of the type particularly adapted to be mounted on automobiles. The apparatus according to the invention is provided with a fixed base frame carrying the operating device, and with a cassettes carrying frame which is movable in parallel relationship to itself with respect to the base frame from one rest position away from the base frame, in which position the bobins in the cassette are out of engagement from the tape reel driving shaft of the tape driving mechanism and the cassettes may be inserted in, or expelled from the cassette carrying frame, to an operating position near the base frame in which the reel driving shaft of the tape driving mechanism is into engagement with one bobin of the cassette.

According to the invention, the cassettes magnetic tapes recording and/or reproducing apparatus is substantially characterized by the fact that the cassettes carrying frame effects, starting from its rest position and after the introduction of the cassette, at first a movement toward the interior of the device, in a direction substantially parallel to the base frame so as to bring one bobin of the cassette into axial alignment with the reel driving shaft, and thereafter a movement in a direction substantially at right angles toward the base frame, causing the said bobin of the cassette to engage the reel driving shaft, and thereafter starting from its operating position, a disengagement movement in a direction substantially at right angles away from the base frame, so as to disengage the bobin from the reel driving shaft, and subsequently a return movement to the rest position, in a direction substantially parallel to the base frame.

According to a further feature of the invention, the abovementioned sequence of movements of the cassettes carrier frame may be obtained with the aid of at least one lever pivotably mounted in a plane substantially at right angles both to the base frame and to the cassettes carrier frame around a pivot slidably guided in a direction parallel to the base frame, which lever is further provided with two additional arms, one of which is pivoted to the cassettes carrier frame and which is into engagement at this pivot point with one L shaped guide comprising one length parallel to the base frame and one length directed toward the base frame and substantially at right angles with it, whilst the second arm of the said lever is into engagement with a guide which is substantially at right angles to the base frame, said guide being formed in an entraining slide which is guided so as to move in a direction parallel to the base frame, in the same direction as the cassettes carrier frame, between one rest position and one operating position corresponding to the rest and operating positions of the cassette carrier frame, means being provided for displacing the entraining slide from its rest position at least up to the operating position and backwards, and locking means for holding the entraining slide in its operating position.

Preferably, according to a further feature of the invention, the entraining slide is moved for a certain length beyond its operating position, up to a stop position, whilst maintaining the cassette carrier frame in its operating position and deriving from this residual end movement of the entraining slide any desired control for the recording and/or reproducing magnetic tape cassettes device. In this case, the entraining slide is maintained by the locking means in its stop position, beyond its operating position.

The movement of the entraining slide from its rest position to its operating position and also beyond this position up to its stop position may be controlled manually and/or by means of an electric motor, more particularly by means of the electric motor of the driving mechanism of the magnetic cassettes recording and/or reproducing device, by starting preferably automatically the said motor, for example by the introduction of the cassette in the cassettes carrying frame, and/or by manually pushing the cassettes carrying frame toward the interior.The backward movement of the entrainment slide, from its operating or stop position to its rest position, is preferably effected by means of at least one return spring which is loaded by the forward movement of the entraining slide from its rest position to its operating position and which act on the said entraining slide whenever same is unlocked from the locking device.

The locking device holding the entraining slide in its operating or stop position may be constructed and controlled in any desired manner. It may be controlled either by the user or automatically, mechanically and/or electrically, and for instance it may be controlled by means of an electromagnet which may be energized or de-energized through a manual control by the user and/or through a pulse from the magnetic tape.

The above and other features of the invention and the advantages deriving from it will be evident from the following description of a preferred embodiment of the inventions shown by way of non limiting example in the annexed drawings, in which: Figure 1 is a perspective partial view of the mechanical components of a magnetic tape cassette recording and/or reproducing device according to the invention.

Figures 2, 3 and 4 are side views of the device of Fig. 1 from the side of arrow II of Fig. 1, showing the mechanical components in three succeeding positions.

Figures 5, 6 and 7 are views corresponding to the views of Figs. 2, 3 and 4, viewed from the external side, in the direction of arrow V of Fig. 1.

Figures 8 and 9 are two different positions of the electrical switch provided on the external side of the mechanical components of Fig.

1, taken in the direction of arrow VIII.

Figure 10 is a bottom plan view of the mechanical components of Fig. 1, and Figure 11 is a partial view corresponding to the view of Fig. 10, with the components shown in a different operating position.

In the drawings, only the essential mechanical components of a magnetic tape cassettes recording and/or reproducing device are shown, the remaining components being evident to a person skilled in the art, and being subject to variations.

The mechanical components shown comprises a fixed base frame, formed by two parallel superimposed and spaced apart plates 1 and 2, connected together by the side pieces 3 and 4 and by the rear cross piece 5.

On said base frame 1, 2, between the sides 3, 4 a movable cassette carrier frame is disposed, formed by two superimposed and spaced apart, apertured plates 6, 7 connected together by a side piece 8 adjacent to the side piece 4 of the base frame 1, 2. The upper plate 6 is provided with a transversal extension 106 extending up to the opposite side piece 3 of the base frame 1, 2, and ending with a short side piece 108. The two plates 6, 7 of the movable cassettes carrier frame define the receptacle for the cassettes C. The later is introduced between the plates 6, 7 in the directjon of the arrow F until abutment against an abutment member formed, by example, by the bended rear edge 206 of the upper plate 6.

On the fixed base frame the driving mechanism of the magnetic tape cassettes recorder or reproducer is mounted. The said driving mechanism comprises one electric motor 9 secured to the upper side of the upper plate 2 of the base frame which drives a pulley 10 disposed on the lower side of the said plate 2 (Figs. 10 and 11). The pulley 10 is connected through a belt 11 to a second pulley 12 integral with a coaxial pinion 13 disposed on the upper side of the upper plate 2 of the base frame. From said pinion 13 the drive for the reel driving shaft, (not shown) projecting upwardly from the base frame 1, 2 in direction of the cassettes carrying frame 6, 7, may be derived by any suitable transmission.

Between the two plates 1, 2 of the base frame an entrainment slide is mounted, comprising a transverse member 14 and two side members 114, 214 integral therewith, adjacent to the inner sides of the side pieces 4 and 3 of the base frame 1, 2. The entraining slide 14, 114, 214 is mounted so as to slide in a direction parallel to the plates 1, 2 of the base frame, to and fro in the direction F of introduction of the cassettes C, and is guided for his movement by the pins 15, 16 and 17 sliding into straight slots 18, 19 and 20 formed in the side pieces 3, 4 of the base frame 1, 2.

The transverse member 14 of the entraining slide is provided at its rear edge with an abutment wing 21 (Fig. 10 and 11) cooperating with an entraining pin or reel 22 eccentrically projecting from a toothed wheel 23 in mesh with a pinion 24.

The pinion 24 is operated by the pulley 12 through a transmission comprising a pulley 25 integral and coaxial to pulley 12, a pulley 26 integral and coaxial to pinion 24, and a belt transmission 27 between pulleys 25 and 26. The toothed wheel 23 is provided with a non-toothed sector 123 and is integral with a circular body 28 provided with two diametrically opposed side flats. This faceted body 28 cooperates with one arm of a V shaped spring 29, the second arm of which is secured to the base frame 1, 2. Moreover, the entraining pin 22 cooperates with a ratchet 30 fulchrumed at 130 to the base frame 1, 2 and urged by a spring 31 toward said entraining pin 22. The ratchet 30 cooperates further with a release pin 32 mounted on the transverse member 14 of the entraining slide.

The cassette carrier frame 6, 7 and the entraining slide 14, 114, 214 are coupled together by means of three levers 33, two of which are disposed on the inner side of the side piece 4 and the other is disposed on the inner side of the side piece 3 of the base frame 1, 2. Each of said levers 33 is swingable in a plane at right angles to the sliding plane of the entraining slide and is substantially star-like shaped with three arms 133, 233 and 333. The arm 133 carries a pin 34 forming the fulchrum of the lever 33 and same is engaged in a rotatable and slidable manner in a straight guide slot 35 formed in the corresponding side piece 3, 4 of the base frame 1, 2, said guide slot being parallel to the sliding plane of the entrainment slide 14, 114, 214. Another arm 233 of the lever 33 is pivoted by means of a pin 36 to the corresponding side piece 8, 108 of the movable cassettes carrier frame 6, 7. This pin 36 of the lever 33 is into engagement with a guide slot formed in the corresponding side piece 3, 4 of the base frame 1, 2 and formed by a length 37 parallel to the sliding plane of the entraining slide 14, 114, 214 and by an attached descending comparatively width length 137 which is substantially at right angles to the sliding plane of the entrainment slide.The third arm 333 of each lever 33 is substantially directed downwardly toward the entrainment slide and is provided with a pin 38 into engagement with a guide slot formed in the corresponding side piece 11 4, 21 4 of the entraining slide, and formed by a length 39 at right angles to the sliding plane of the entrainment slide and by an annexed length 139 parallel to the said sliding plane.

On the exterior side of the side piece 3 of the base frame 1, 2, an electric switch is mounted, comprising two fixed spaced apart contacts 40, 41, and one intermediante movable contact 42 connected through a loop 43 to one elastic blade 44 cooperating with the pin 36 of the arm 233 of the lever 33. On the other side piece 4 of the base frame 1, 2 a locking device is secured comprising a ratchet 45 fulchrumed at 145 to the side piece 4 and cooperating with the guide pin 15 of the entrainement slide. The said ratchet 45 is urged downwardly by a spring 46 and cooperates with the anchor 47 of the electromagnet 48 secured to the outer side of the side piece 4. The anchor 47 is fulchrumed at 145 and is provided with a pin 49 which is apt to engage the lower edge of the ratchet 45.A spring 50, stronger than spring 46, tends to withdrawn the anchor 47 of the electromagnet 48 causing it to rotate in clockwise direction around fulchrum 145 of Figs. 5, 6 and 7 thus lifting the pin 49 toward the ratchet 45. The anchor 47 is further provided with an appendix 147 extending along the guide slot 18 which may be overlaped by the guide pin 15 of the entraining slide 14, 114, 214 sliding in the said slot 18.

The above described mechanism for magnetic tape cassettes recording and/or reproducing devices operates as follows.

The rest position of the device is shown in Figs. 1, 2, 5, 8 and 10. The entrainment slide 14, 114, 214 is urged by a spring 51 toward the cassettes C introducing and expelling opening (left hand side in Figs. 1, 2, 8 and 10 and right hand side in Fig. 5) and is stopped, for instance, by the abutment of the pins 1 5, 1 6, 1 7 against the respective ends of the guide slots 18, 1 9 and 20.

Whenever energized, the electromagnet 48 attracts the anchor 47 in opposition to the force of the spring 50. The anchor 47 thus assumes an unlocking position, in which its pin 49 frees the ratchet 45, which is urged downwardly by the spring 46. Concurrently the guide pin 15 of the slide 14, 114, 214 overlaps the appendix 147 of the anchor 47, thus locking same also mechanically in its position attracted by the electromagnet 48. In the driving mechanism (Fig. 10) one arm of the spring 29 adheres against one flat of the faceted body 28 thus maintaining the toothed wheel 23 in an angular starting position, in which the pinion 24 is in mesh with the leading end of the toothed portion of the wheel 23, at the end of the non-toothed sector 123.The ratchet 30 is kept out of engagement with the entraining pin 22 by the toothed wheel 23, against the action of the spring 31 and by effect of the pin 32 integral with the transverse member 14 of the entraining slide. Also the cassettes carrier frame 6, 7 is in its rest position, shifted toward the opening of introduction and expulsion of the cassettes C into and fro the recording and/or reproducing device. The pins 36 of the arms 233 of the levers 33 are into abutment against the ends of the guide slots 37 parallel to the sliding plane of the entraining slide, whilst the pins 38 of the arms 333 of the levers 33 are engaged in the guide slots 39 at right angles to the sliding plane of said slide.

The pin 36 of the lever 33 associated with the side piece 3 of the base frame 1, 2 maintains the elastic blade 44 of the electric switch (Fig.

8) into depressed condition, so that the movable contact 42 adheres against the upper fixed contact 41 and the electric motor 9 is deenergized.

By introducing the cassette C in the movable cassettes carrier frame between the two plates 6, 7 and by slightly pushing said frame 6, 7 toward the interior in the direction of the arrow F by means of the same cassette C into abutment with the rear abutment edge 206, also the entrainment slide 14, 114, 214 is correspondingly shifted by means of the levers 33 which maintain their angular position unmodified and which slides with their pins 36 and 34 in the corresponding slots 35 and 37.

The pin 36 of the levers 33 disposed on the side of the side piece 3 of the base frame 1, 2 frees the elastic blade 44 of the electric switch. The blade 44 moves upwardly thus releasing the movable contact 42, under the action of the loop 43, from the position of Fig. 8 to the position of Fig. 9, in which the movable contact 42 adheres against the fixed lower contact 40. In this manner the electric motor 9 is started thus causing, through pinion 24, the rotation of the toothed wheel 23 in the direction of arrow F1 of Fig. 10. The entraining pin 22 of the toothed wheel 23 causes a further forward movement of the entraining slide 14, 114, 214 in the same direction of arrow F, by engagement with the abutment wing 21 of the transverse member 14 of said slide.

During the next automatic forward movement of the entraining slide 14, 114, 214 in the direction of the arrow F controlled by the electric motor 9, the pin 32 on the transverse member 14 of the slide (Fig. 10) frees the ratchet 30 which is brought by the spring 31 in a position in which it interfers with the path of the entraining pin 22. Moreover, the pin 15 of the entraining slide 14, 114, 214 by sliding in the corresponding guide slot 18, frees the projection 147 of the anchor 47, but same remains into its unlocking position by effect of the electromagnet 48 which is still energized (Fig. 6).

The slide 14, 114, 214 during its forward movement, controlled by the motor 9, toward the interior of the recording and/or reproducing device in the direction F of introduction of the cassettes C, entrains the cassettes carrier frame 6, 7 together with the cassette C housed inside of it. The said entrainment is performed through the levers 33 which in a first time do not change their angular position and just slide with their pins 34 and 36 in the respective guide slots 35 and 37. As soon as the fulchrum pins are stopped at the end of the respective guide slots, the pins 36 of the levers 33 comes in correspondence of the guide slots 137 at right angles to the sliding plane of the entrainment slide 14, 114, 214.

In the corresponding position of the cassettes carrying frame 6, 7 the hub or central hole of one of the two bobins of the cassette C housed in the cassettes carrying frame comes to be above the tape driving shaft, (not shown) in axial alignment therewith. During the further forward movement of the entraining slide 14, 114, 214 the levers 33, which cannot more slide together with the slide, are angularly shifted by the slide, and are oscillated around their fulchrum pins 34. The arms 233 of the levers 33 are thus oscillated downwardly, that is in direction of the base frame 1, 2, and are moved with their pins 36 in the descending length 137 of the respective guide slots, thus lowering the cassettes carrier frame 6, 7 together with the cassette C toward the base frame 1, 2, as shown in Figs.

3 and 6. In this manner, at the end of its forward movement toward the interior, the movable cassettes carrier frame 6, 7 performs a lowering or engagement movement, directed at right angles toward the base frame, at the end of which the cassettes carrier frame assumes a lowered operative position, in which the bobin in cassette C is coupled to the underlying reel driving shaft. Concurrently, also the other arm 333 of the levers 33 is substantially shifted at right angles toward the base frame so that the pins of said arms 333 are disengaged from the respective guide slots 39 directed at right angles to the sliding plane of the entraining slide 14, 114, 214 and are positioned in correspondence of the annexed guide slot 139 parallel to the sliding plane of the entraining slide, as shown in Fig. 3.

The entrainment slide 14, 114, 214 is however caused to prosecute beyond its operative position corresponding to the above described lower operative position of the cassettes carrier frame 6, 7 until it reaches a stop position shown in Figs. 4, 7 and 11. During this residual forward stroke of the entrainment slide, the guide pins 38 of the arms 333 of the levers 33 slide in the slots 139 of the entrainment slide, parallel to the sliding plane of said slide, with the levers 33 at standstill and same are maintained in their angular position corresponding to the lowered operative position of the cassettes carrier frame 6, 7 (Fig. 4). The guide pin 15 df the entraining slide 14, 114, 214 glides under the lowered ratchet 45, lifting it automatically against the action of the spring 46 (Fig. 6).As soon as the guide pin 15 passes beyond the ratchet 45, the entrainment slide 14, 114, 214 reaches its stop position. The ratchet 45 is thus lowered, also by action of the spring 46, and by engagement with the guide pin 15, holds the entrainment slide 14, 114, 214 in its stop position against the action of the return spring 51, as shown in Fig. 7. At the same time, the toothed wheel 23 has accomplished an almost complete rotation, so that its non-toothed sector 123 comes to be in correspondence of the pinion 24, whilst the entraining pin 22 comes into engagement with the ratchet 30, as shown in Fig. 11.The pinion 24 prosecutes in its rotation, since it is coupled to the electric motor 9 of the recording and/or reproducing device, but it does no more entrain into rotation the toothed wheel 23 since it is no more into engagement with the teeths of said wheel 23, but is in correspondence of the non-toothed sector 123.

The spring 29 bears with its arm against the edge of a flattening of the faceted body 28, thus exterting on said body, and by consequence on the toothed wheel 23, a rotational moment in the direction of the arrow F1. The toothed wheel 23 remains however in standstill since it is stopped by the ratchet 30.

The residual stroke of the entraining slide 14, 114, 214 from its operative position according to Figs. 3 and 6 to its stop position of Figs. 4 and 7 is used for automatically deriving any other control of the magnetic tape recording and/or reproducing device.

In order to expell the cassette C, the electromagnet 48 which up to this moment was maintaining the anchor 47 in release position, is de-energized. The said de-energizing may be controlled either manually and/or by an automatic control provided for instance by the magnetic tape. The thus freed anchor 47 is urged by the spring 50 in clockwise direction in Fig. 7 thus lifting through its pin 49 the ratchet 45 thus disengaging it from the guide pin 15 of the entrainment slide 14, 114, 214. The entrainment slide is thus released and returned by the return spring 51 suddenly from its stop position of Figs. 4, 7 and 11 to its rest position of Figs. 1, 2, 5, 8 and 10, in the direction opposite to arrow F and by passing through the operative position of Figs. 3 and 6. The levers 33 and the cassettes carrying movable frame 6, 7 are thus effecting at reverse the movements above described.

More particularly, the cassettes carrier frame 6, 7 effects at first a disengaging movement by moving away at right angles from the sliding plane of the entrainment slide 14, 114 214, that is by lifting itself from the base frame 1, 2 in order to disengage the bobin of the cassette C from the reel driving shaft. Soon after, the cassettes carrier frame C comes in its rest position of Figs. 1, 2, 5, 8 and 10, by a return movement parallel to the sliding plane of the entrainment slide 14, 114, 214, that is a movement parallel to the fixed frame 1, 2. The cassette C may be thus extracted from the cassettes carrying frame 6, 7.

Concurrently, toward the end of the return stroke of the entrainment slide 14, 11 4, 214 the release pin 32 of the transversal member 14 of said slide abuts against the ratchet 30 releasing it from the entrainment pin 22 of the toothed wheel 23, thus returning said ratchet 30, against the action of the spring 31, in its release position according to Fig.

10. The rotation moment exerted by the spring 29 on the faceted body 28, causes the toothed wheel 23 to rotate by a small angle forwardly in the direction of arrow F1, from the angular position of Fig. 11 to that of Fig.

10, so as to bring again the pinion 24 into mesh with the leading end of the toothed sector of the toothed wheel 23, at the end of the non-toothed sector 123. The pinion 24 is however stopped, since as soon as the cassette carrier frame 6, 7 comes in its rest position, it operates again by means of its guide pin 36 the electric switch, by depressing the elastic blade 44 which tripps the movable contact 42 from the position of Fig.

9 back to the position of Fig. 8, thus stopping the electric motor 9. All the parts of the mechanical device for magnetic tape cassettes recording or reproducing devices are thus reset to their starting positions, and the device is ready to receive a new cassette.

Of course, the invention is not limited to the embodiment described and shown, and may be amply varied and modified, mainly in its construction and within the limits of the mechanical equivalents, without abandoning the above described inventive concept, as claimed in the following claims.

Claims (12)

1. A magnetic tape cassette transport mechanism having at least one reel driving shaft for rotating a reel of magnetic tape in a tape cassette, wherein the mechanism comprises a cassette carrying member movable firstly from a cassette receiving position in a lateral direction relative to the axis or axes of rotation of the or each reel driving shaft to an intermediate position, and secondly from the intermediate position in a direction generally parallel to the said axis or axes to a cassette playing position.

2. An apparatus for reproducing and/or recording magnetic tape in cassettes, particularly apt for use on automobiles radio equipments or the like, comprising in combination, a fixed base frame carrying the tape driving mechanism, a cassettes carrying frame which is movable parallel to itself with respect to the base frame from a rest position far from the base frame in which the bobins of the cassette are out of engagement with the reel driving shaft of the tape driving mechanism and in which the cassettes may be introduced in, or expelled from the cassettes carrying frame, and one operative position near the base frame in which one bobin of the cassette is into engagement with the reel driving shaft of the tape driving mechanism, and back, characterized by the fact that means are provided for causing the cassettes carrying frame to effect, starting from its rest position and after the introduction of one cassette, at first one forward movement toward the interior of the device, substantially parallel to the base frame, in order to bring one bobin of the cassette into axial alignment with the reel driving shaft and thereafter a coupling movement directed substantially at right angles toward the base frame, so as to bring the said bobin of the cassette into engagement with the reel driving shaft and to cause, starting from this operative position, at first a disengagement movement directed substantially at right angles with respect to the base frame in a direction away from said frame so as to disengage the bobin of the cassette from the reel driving shaft of the tape driving mechanism, and thereafter a return movement back to the rest position, in a direction substantially parallel to the base frame.

3. An apparatus according to claim 2, characterized by at least one lever fulchrumed so as to rock in a plane substantially at right angles both to the said base frame and to the said cassettes carrying frame around a fulchrum slidably guided in a direction parallel to the base frame, the said lever being further provided with a second and a third arm; the said second arm of said lever being pivoted to the cassettes carrying frame and being into engagement through this pivot with an L shaped guide comprising a length parallel to the base frame and a length directed toward the base frame and substantially at right angles with respect to said frame; an entrainment slide on said base frame guided for movement in a direction parallel to the base frame, in the same direction of the cassettes carrying frame, between one rest position and one operative position corresponding to the rest and operative positions of the cassette carrying frame; the third arm of said lever being into engagement with a guide directed substantially at right angles with respect to the base frame, formed in said entrainment slide; and means for moving the entrainment slide from its rest position at least up to its operative position, and back, and stop means for maintaining the entrainment slide in its operative position.

4. An apparatus according to claim 3, comprising means for moving said entrainment slide by a certain length beyond its operative position, up to a stop position, whilst maintaining the cassettes carrying frame in its operative position, means for locking said slide in said stop position, and means for deriving from this residual end movement of the entrainment slide any desired control for the magnetic tape recording and/or reproducing device.

5. An apparatus according to claim 3, characterized by the fact that the guide formed in the entrainment slide at right angles to the base frame and with which one arm of the rocking lever is into engagement, is connected to a guide parallel to the base frame, in which the said arm of the rocking lever may slide.

6. An apparatus according to claim 3, characterized by the fact that more than one rocking levers are provided, in the number of at least one for each side of the cassettes carrier frame and preferably at least two rocking levers are provided on at least one side piece of the cassettes carrying frame and at least one rocking lever is provided on the opposite side of the said cassettes carrying frame.

7. An apparatus according to claim 4, characterized by the fact that the means for locking the entrainment slide are formed by a ratchet cooperating with a projection of said slide and oscillating in a plane at right angles to the sliding plane of the entrainment slide, the said ratchet being urged by spring means toward its locking position into engagement with the projection of the entrainment slide, whilst it may be disengaged from this projection by means of a manually and/or electrically operated disengagement lever.

8. An apparatus according to claim 7, characterized by the fact that the disengagement lever is connected to the anchor of an electromagnet and is maintained by the electromagnet in a rest position, whilst whenever the said electromagnet is deenergized, it is shifted by spring means in a positive ratchet disengaging position from the projection of the entrainment slide.

9. An apparatus according to the preceeding claims, characterized by the fact that the entrainment slide is moved by means of a manual control from its rest position to its operative or stop position.

10. An apparatus according to claim 3, characterized by the fact that the entrainment slide is moved automatically from its rest position to its operative or stop position by means of an electric motor which is started preferably by the introduction of the cassette in the cassettes carrying frame and/or by a short manual forward movement toward the interior of the cassette carrying frame itself.

11. An apparatus according to claim 10 characterized by the fact that the electric motor operates, by means of a pinion, a toothed wheel provided with a non-toothed sector and further provided with an excentric entrainment pin or reel which is apt to engage an abutment wing, or the like, of the entrainment slide so as to move same from its rest position to its operative or stop position, against the action of return spring means, by a single rotation of the toothed wheel, means being provided for automatically blocking the rotation of the toothed wheel in the operative or stop position of the entrainment slide, in which the non-toothed sector of the toothed wheel is in correspondence of the operating pinion, as well as means for automatically unlock the rotation of the toothed wheel and for rotating it just for that amount which is requested in order to bring its toothed sector in mesh with the operating pinion, whenever the entraining slide is returned to its rest position.

12. A recording and/or reproducing magnetic tape cassette device, substantially as described and shown in the attached drawings.