GB2217506A - Tape feeding device - Google Patents

Abstract

Reel hub gears are driven by a motor gear train which progresses to a gear 27 coupled onwards to a coaxial gear 29 through a high torque frictional coupling 49 so as, with gear 31, to selectively provide fast drive forward or reverse to a fast wind idler gear (34), and is also coupled through a low torque frictional coupling 47 to drive gears 28,30, small gears 28a and 30a of which selectively engage for forward or reverse drive of slow speed idler gear (33). The coupling 49 has radial spring fingers 49a engaging the inner wall of peripheral flange 29a. A spring 48 provides pressure for the felt ring 47 comprising the low torque coupling. A corrugated ring element (86) (fig 10) may comprise the high torque coupling. The couplings may be separate coaxial spring loaded felt discs on opposite sides of the directly driven gear, (Fig 11). No frictional clutches are required in the reel hubs. The slow speed idler gear is controlled for automatic reverse and the high speed idler mounting is interlocked with the head mounting plate. <IMAGE>

Description

TAPE FEEDING DEVICE BACKGROUND OF THE INVENTION 1) - Field of the Invention This invention relates to a tate feeding device wherein a turning force of a motor is transmitted at a predetermined speed or at a higher speed selectively to a pair of reel receivers, and more particularly to improvements in or relating to a friction transmission mechanism of a tape feeding device of the type mentioned.

2) #Des#cri#tion of the Prior Art A tape feeding device for-a tape recorder of the type which includes an automatic reversing mechanism is already known. An exemplary one of such known tape feeding devices is shown in FIG. 12.

Referring to FIG. 12, a turning force of a motor pulley 2 directly connected to a rotary shaft of a motor 1 is transmitted to a pair of capstan fly-wheels 3a and 3b and a pulley 4 with an integral gear by means of respective belts. The gear of the pulley 4 is held in meshing engagement with a large diameter one of three large, intermediate and small diameter gears of a gear member 5. A clutch gear 6 and a tape feeding direction change-over driving gear 7 are held in meshing engagement with the intermediate and small diameter gears of the gear member D, respectively.An intermittent gear 8 is brought into meshing engagement with the tape feeding direction change-over driving gear 7 in response to a tape end detection signal which is developed when a magnetic tape is fed to its end. The turning force of the intermittent gear is utilized to shift a pair of left and right pinch rollers not shown alternatively into and out of contact with a corresponding pair of capstans 9a and 9b.

A torque transmitting gear 10 is disposed in a concentrical relationship with the clutch gear 6. The torque transmitting gear 10 is pressed axially against the clutch gear 6 by a spring mechanism not shown to produce a contact resistance between the gears 6 and 10, thereby constituting a first friction transmission mechanism though not particularly shown in FIG. 12. A large diameter one of a pair of integral large and small diameter gears of a gear member 11 is held in meshing engagement with the torque transmitting gear 10, and a large diameter one of a pair of integral large and small diameter gears of another gear member 12 is held in meshing engagement with the large diameter gear of the gear member 11.Rotation of the small diameter gear of the gear member 11 is selectively transmitted to a forward side reel gear 14b via a forward side low speed transmitting idler 13b while rotation of the small diameter gear of the gear member 12 is selectively transmitted to a reverse side reel gear 14a via a reverse side low speed rotation transmitting idler 13a.

When the pinch rollers are alternatively shifted into or out of contact with the capstans 9a and 9b, the low speed rotation transmitting idlers 13a and 13b are alternately brought out of respective rotation transmitting routes.

A pair of reverse and forward side reel receivers 15a and 15b are disposed in a coaxial relationship with the reel gears 14a and 14b, respectively. Rotation of the reel gears 14a and 14b are transmitted to the reel receivers 15a and 15b, respectively, via respective second friction transmission mechanisms not shown.

A forward side high speed rotation transmitting idler 16b and a reverse side high speed rotation transmitting idler 16a are held in meshing engagement with the large diameter gears of the gear members 11 and 12, respectively. Upon forward feeding of a tape at a high speed, the forward side high speed rotation transmitting idler 16b is shifted also into meshing engagement with the reel gear Ilb, and alternatively upon reverse feeding of the tape at a high speed, the reverse side high speed rotation transmitting idler 16a is shifted into meshing engagement with the reel gear 14a.

It is to be noted that, in FIG. 12, the gears are all represented by mere circles corresponding to pitch circles thereof while points at which the gears mesh with each other are represented by small black circles or points.

With the tape feeding device of the construction described above, when a manually operable member not shown is manually operated to feed a magnetic tape at a constant low speed for recording or reproduction, a magnetic head not shown is shifted into contact with the magnetic tape and one of the pinch rollers, for example, the forward side pinch roller is pressed against the corresponding capstan 9b while the low speed rotation transmitting idler 13b on the same side is shifted into meshing engagement with the reel gear 14b. The turning force of the motor 1 is thus transmitted to the reel receiver 15b via the pulley 4, ear member 5, clutch gear 6, first friction transmission mechanism, torque transmitting gear 10, gear member 11, low speed rotation transmitting idler 13b, reel gear 14b and second friction transmission mechanism.

The magnetic tape is thus wound onto the reel on the forward side. Then, when the magnetic tape has been completely wound up and comes to its extreme end, the tape end is detected and a tape end detection signal is developed by suitable means not shown. In response to the tape end detection signal, the intermittent gear 8 is brought into meshing engagement with the tape feeding direction change-over driving gear 7. Consequently, the intermittent gear 8 is rotated by the tape feeding direction change-over driving gear 7 thereby to move the forward side pinch roller out of contact with the capstan 9b and move the reverse side pinch roller into contact with the capstan 9a instead.In response to such a sequence of operations, the forward side low speed rotation transmitting idler 13b is shifted out of meshing engagement with the reel gear 14b while the reverse side low speed rotation transmitting idler 13a is shifted into meshing engagement with the reel gear 14a, thereby changing over the feeding direction of the magnetic tape to allow a recording or reproducing operation to be thereafter resumed.

To the contrary, when another manually operable member not shown is manually operated to start high speed forward feeding of the magnetic tape while the magnetic tape is being fed and wound onto the forward side reel to proceed recording or reproducing operation, the forward side pinch roller is shifted out of contact with the capstan 9b while the forward side low speed rotation transmitting idler 13b is shifted out of meshing engagement with the gear member 11 to stop its rotation transmitting function, and the magnetic head is moved a little distance away from the magnetic tape.

Simultaneously, the forward side high speed rotation transmitting idler 16b is shifted into meshing engagement with the-reel gear lOb. Consequently, the turning force of the motor 1 is transmitted at a high speed to the reel receiver 15b via the pulley 4, gear member 5, clutch gear 6, first friction transmission mechanism, torque transmitting gear 10, gear member il, forward side high speed rotation transmitting idler 16b, reel gear lAb and second friction transmission mechanism so that the magnetic tape is wound onto the forward side reel at a high speed. When the tape is wound at a high speed in this manner and comes to its final end, the system from the torque transmitting gear 10 to the reel receiver 15b is compulsorily stopped by tension of the magnetic tape. Consequently, a slip is yielded in the direction of rotation in the first friction transmission mechanism between the clutch gear 6 and the torque transmitting gear 10 so that the system from the motor 1 to the clutch gear 6 is allowed to continue its rotation.

Various tape recorder constructions have been proposed in connection with such a condition reached as described just above. For example, an automatic stopping mechanism may be rendered operative in response to a tape end detection signal when the condition described above is reached. Or, the tape feeding direction may be changed over to start a reproducing operation in the reverse direction. Or else, the feeding device is left in the condition in which a slip is yielded in the direction of rotation in the first friction transmission mechanism until a further manually operable member is manually operated to stop operation of the tape feeding device.

The conventional tape feeding device having such a construction as described above has following problems.

As a general matter at first, when a magnetic tape is fed at a predetermined low speed for recording or reproduction, the feeding speed of the tape is defined with a high degree of accuracy by the turning speed of a capstan while the tape winding speed of a reel receiver is set a little faster than the tape feeding speed and an excessive amount of the speed then is absorbed by a second friction transmission mechanism for allowing feeding of the tape at a low speed such as the friction transmission mechanism provided between the reel gear 14a or 14b and the reel receiver 15a or 15b in the arrangement of FIG. 12. Therefore, the turning force of the reel receiver is defined by the second friction transmission mechanism.The turning force of the reel receiver is preferably set as small as possible because a great turning force of the reel receiver may cause such a bad influence that the turning speed of the capstan is increased.

To the contrary, when the tape is fed at a high speed, the pinch roller is shifted out of contact with the capstan so that rotation of the capstan does not have an influence on the feeding speed of the tape. The reel receiver is thus rotated at a high speed to wind the tape at a high speed. The turning force of the reel receiver then is preferably set as great as possible because small turning force of the reel receiver may not possibly allow winding of the tape with certainty.

It is thus desirable that the turning force of the reel receiver is minimized for feeding of a tape at a low speed but maximized for feeding at a high speed.

With the tape feeding device of FIG. 12, however, the turning force of the motor 1 is transmitted to the reel receiver 15a or 15b via the first friction transmission mechanism and the second friction transmission mechanism whether the tape is fed at a low speed or at a high speed, and upon low speed feeding of the tape, a slip is yielded in the second friction transmission mechanism, but after the tape is fed to its extreme end during high speed feeding thereof, a slip is yielded in the first friction transmission mechanism. Thus, a slip is yielded in the second friction transmission mechanism to decrease the turning force of the reel receiver during low speed feeding.Accordingly, there is a limitation in reduction of the rotation transmitting force of the reel receiver upon low speed feeding, which makes it impossible to meet the demand to minimize the rotation transmitting force of the reel receiver.

Further, the arrangement of FIG. 12 is complicated in construction because the friction transmission mechanisms are disposed at three locations.

Simplification of the arrangement is thus desired.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tape feeding device wherein a turning force of a reel receiver for feeding of a tape at a predetermined low speed and a turning force of the reel receiver for feeding of the tape at a high speed can be set freely independently of each other and simplification in construction can be attained.

In order to attain the object, according to the present invention, there is provided a tape feeding device of the type wherein a turning force of a motor is transmitted at a predetermined speed or a higher speed selectively to a pair of reel receivers, comprising a first rotary plate connected to receive the turning force of the motor, second and third rotary plates disposed in a coaxial relationship with the first rotary plate, first and second friction transmission mechanisms for transmitting the turning force of the first rotary plate to the second and third rotary plates, respectively, with different rotation transmitting forces, a low speed rotation transmitting idler operable for transmitting the smaller turning force of the second rotary plate selectively to the pair of reel receivers, and a high speed rotation transmitting idler operable alternatively to the low speed rotation transmitting idler for transmitting the greater turning force of the third rotary plate selectively to the pair of reel receivers.

With the tape feeding device, when a tape is to be fed at the predetermined speed, the turning force of the motor is transmitted to a selected one of the reel receivers via the first friction transmission mechanism, but to the contrary when the tape is to be fed at the higher speed, the turning force of the motor is transmitted to the selected reel receiver via the second friction transmission mechanism.

Accordingly, the rotation transmitting force of the first friction transmission mechanism can be made as small as possible in order to minimize the turning force of the reel receiver upon forward feeding of the tape at the predetermined speed while the turning force of the reel receiver for feeding of the tape at the higher speed can be set to a high level independently of the rotation transmitting force of the first friction transmission mechanism.

Besides, since the first and second friction transmission mechanisms are disposed in a concentrated manner at a single location, reduction in quantity of parts and simplification in construction can be attained.

A specific embodiment of the present invention will now be described in detail by way of example with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 4 are plan views of rotation transmitting routes of a tape feeding device in different positions showing a first embodiment of the present invention; FIG. 5 is a fragmentary perspective view of a friction transmission mechanism and associated parts of the tape feeding device of FIG. 1; FIG. 6 is a vertical sectional view of the friction transmission mechanism and the associated parts of FIG. 5; FIG. 7 is a fragmentary perspective view of a cassette holder and associated parts of the tape feeding device of FIG. 1; FIGS. 8 and 9 are side elevational views showing the cassette holder and an eject lever of the tape feeding device of FIG. 1 in different positions; ; FIG. 10 is a fragmentary perspective view of a friction transmission mechanism and associated parts of a tape feeding device showing a second embodiment of the present invention; FIG. 11 is a fragmentary perspective view of a friction transmission mechanism and associated parts of a tape feeding device showing a third embodiment of the present invention; and FIG. 12 is a plan view of rotation transmitting routes of a conventional tape feeding device.

DETAILED DESCRIPTION OF THE ILLUSTRATED~EMBODIMENTS Referring first to FIGS. 1 to 4, rotation transmitting routes of a tape feeding device according to a first preferred embodiment of the present invention are shown. The tape feeding device includes a motor 21 a turning force of which is transmitted from a pulley 22 directly connected to a rotary shaft of the motor 21 to a pair of capstan wheels 23a and 23b by means of a belt 22a. The pulley 22 has an integral gear 22b from which the turning force of the motor 21 is transmitted successively to first and second speed reduction gear members 24 and 25 and a tape feeding direction changeover driving gear 26 so that the tape feeding direction change-over driving gear 26 is driven to rotate at a reduced speed.Each of the speed reduction gear members 24 and 25 includes a pair of integral large and small diameter gears, and the large diameter gear of the second gear member 25 is held in meshing engagement with a clutch gear 27 (also refer to FIGS. 5 and 6) which serves as a first rotary member.

A low torque transmitting gear 28 and a high torque transmitting gear 29 which serve as second and third rotary members, respectively, are disposed above the clutch gear 27 with the low torque transmitting gear 28 located above the high torque transmitting gear 29.

The two gears 28 and 29 are mounted for rotation on a hollow shaft 27a (refer to FIGS. 5 and 6# which is formed in an integral relationship with the clutch gear 27. The torque transmitting gears 28 and 29 have a same diameter with the clutch gear 27, and a smaller diameter gear 28a is provided in an integral relationship on an upper face of the low torque transmitting gear 28 located above the high torque transmitting gear 29.

First and second reversing gears 30 and 31 having a same diameter with the clutch gear 27 are disposed in a coaxial relationship adjacent the clutch gear 27 and held in meshing engagement with the low torque transmitting gear 28 and the high torque transmitting gear 29, respectively. A smaller diameter gear 30a having a same diameter with the smaller diameter gear 28a is formed in an integral relationship on an upper face of the upper reversing gear 30. The clutch gear 27 and the torque transmitting gears 28 and 29 are located adjacent a forward side reel gear member 32b which includes a pair of integral large and small diameter gears while the reversing gears 30 and 1 are located adjacent a reverse side reel gear member 32a which includes a pair of integral large and small diameter gears.A low speed rotation transmitting idler 33 and a high speed rotation transmitting idler 34 are disposed between the reel gear members 32a and 32b.

A magnetic head 36 is mounted on a head mounting plate 37 which is in turn mounted for linear back and forth sliding movement on a chassis 35 of the tape feeding device.

The low speed rotation transmitting idler 33 is mounted for rotation and also for sliding movement on the head sliding plate 37 in a direction perpendicular to the direction of sliding movement of the head mounting plate 37 from and to a rest position shown in FIG. 1. When the low speed rotation transmitting idler 33 is at the rest position of FIG. 1, it is held in a spaced relationship from the smaller gears 28a and 30a.

If the head mounting plate 37 is advanced to its recording or reproducing operation position in response to manual operation of a manually operable member for recording or reproducing operation, however, the low speed rotation transmitting idler 33 is shifted into meshing engagement with either one of the smaller diameter gears 28a and 30a while it is also brought into meshing engagement with the forward side reel gear member 32b or the reverse side reel gear member 32a (refer to FIGS. 2 and 3). Whether the low speed rotation transmitting idler 33 is meshed with the reverse side reel gear member 32a or the forward side reel gear member 32b depends upon a position of a slide plate 38 which is disposed for movement in a direction perpendicular to the head mounting plate 37 in an overlapping relationship on the head mounting plate 37.

To the contrary, in response to a tape end detection signal when a tape is fed to its final end, an intermittent gear 39 is brought into meshing engagement with the tape feeding direction change-over driving gear 26. Thus, the turning force of the intermittent gear 39 is utilized to slidably move the slide plate 38 to move one of a pair of pinch rollers not shown into or out of meshing engagement with a corresponding one of a pair of capstans 40a and 40b.

Referring to FIGS. 3 and 4, a pivotal plate 41 is mounted for pivotal motion around a shaft 41a on the chassis 35 below the head mounting plate 37. A guide pin 42 is mounted on the pivotal plate 41, and when the guide pin 42 is fitted in a narrow slot 43 formed in the head mounting plate 36, pivotal motion of the pivotal plate 41 is inhibited as shown FIG. 1.

The high speed rotation transmitting idler 34 is supported for rotation at an end portion of the pivotal plate 41. An engaging slot 44 is formed at a rear end portion of the pivotal plate 41, and an engaging pin 46 is engaged in the engaging slot 44 of the pivotal plate 41. The engaging pin 46 is mounted on a feeding direction change-over plate 45 which is mounted for movement in the same direction as the direction of sliding movement of the slide plate 38.If a manually operable high speed forward feeding member not shown is manually operated to cause high speed forward feeding of a magnetic tape, then the feeding direction change-over plate 45 is slidably moved in the rightward direction in FIG. 1 to pivot the pivotal plate 41 in the counterclockwise direction, but if a manually operable high speed reverse feeding member is manually operated to cause high speed reverse feeding of the tape, the feeding direction change-over plate 45 is slidably moved in the leftward direction to pivot the pivotal plate 41 in the clockwise direction. Upon counterclockwise pivotal motion of the pivotal plate 41, the high speed rotation idler 34 is brought into simultaneous meshing engagement with the reversing gear 31 and the small gear of the reverse side reel gear member 32a as shown in solid lines in FIG. 4.To the contrary, upon clockwise pivotal motion of the pivotal plate 41, the high speed rotation idler 34 is brought into simultaneous meshing engagement with the high torque transmitting gear 29 and the small gear of the forward side reel gear member 32b as indicated in phantom in FIG. 4.

Associated parts around the clutch gear 27 and low and high torque transmitting gears 28 and 29 are particularly shown in FIGS. 5 and 6.

Referring to FIGS. 5 and 6, a felt plate 47 is interposed between the low and high torque transmitting gears 28 and 29. A coil spring 48 serving as a first spring member and a tripod spring plate 49 serving as a second spring member are interposed between the clutch gear 27 and the high torque transmitting gear 29 with the tripod spring plate 49 placed on the coil spring 48.

The tripod spring plate 49 has three substantially tangentially extending spring fingers 49a, and three tabs 49b extending downwardly from base portions of the spring fingers 49a. The spring fingers 49a have end portions thereof resiliently pressed against an inner circumferential face of an annular wall 29a formed on a lower face of the high torque transmitting gear 29 while the tabs 49b are inserted in corresponding slits 50 formed in the clutch gear 27.The tape feeding device thus includes a first friction transmission mechanism 51 for applying a low contact resistance to the low torque transmitting gear 28 via the felt plate 47 with the spring force of the coil spring 48 acting in the axial direction, and a second friction transmission mechanism 52 for applying a high contact resistance to the high torque transmitting gear 29 with the spring force by the spring fingers 49a of the tripod spring plate 49 acting in radial or centrifugal directions.

Referring now to FIGS. 7 to 9, there is illustrated a relationship among the chassis 35, a cassette holder 53, an eject lever 54 and associated elements. A pivotal connecting plate 55 is connected for pivotal motion in upward and downward directions to portions of an end edge of the chassis 35. The cassette holder 53 is connected at an upper plate portion thereof for pivotal motion in upward and downward directions to pivotal end portions of the pivotal connecting plate 55.

A slider 56 is mounted for linear sliding movement on the pivotal connecting plate DD, and also a spring receiving member 57 is mounted for pivotal motion on the pivotal connecting plate 55. A toggle spring 58 extends between the slider 56 and a free end portion of the spring receiving member 57.

An arresting member 59 is mounted for pivotal motion on a lower face of the pivotal connecting plate 55 in a coaxial relationship with the spring receiving member 57.

The slider 56 is engaged in one of a pair of reel holes of a tape cassette 60 when the tape cassette 60 is inserted into the cassette holder 53, and as the tape cassette 60 is moved further, the slider 56 is acted upon and moved in the inserting direction by such advancing force of the tape cassette 60 while increasing the amount of resilient deformation of the toggle spring 58. When the slider 56 reaches a predetermined or dead center position, the toggle spring 58 is turned over so that the spring force thereof now acts in the direction to further move the slider 56 in the same direction.

Consequently, the tape cassette 60 is drawn to a predetermined end position into the cassette holder 53 by the spring force of the toggle spring 58.

The arresting plate 59 is provided to arrest the pivotal connecting plate and the cassette holder 53 at respective upper or lifted positions. The eject lever D4 is mounted for linear sliding movement on an outer face of a side wall of the chassis 35. The spring receiving member 57 is connected to the eject lever 54 by way of a connecting link 61.

A cassette lifting plate 63 is mounted for sliding movement in parallel to the eject lever 54 on an inner face of the side wall of the chassis 35. The eject lever 54 and the cassette lifting plate 63 are normally biased in respective returning directions opposite the cassette inserting direction by tension coil springs 64 and 65, respectively.

A pair of inclined guideways 66 are formed in opposite end portions of the cassette lifting plate 63, and a pair of guide projections 67 are provided on an outer face of a side wall of the cassette holder 53 and individually fitted in the inclined guideways 66 of the cassette lifting plate 63. Each of the inclined guideways 66 has a horizontal portion at the top thereof. Due to fitting engagement of the guide projections 67 in the inclined guideways 63, when the lifting plate 63 moves in the cassette inserting direction, the cassette holder 53 is moved upwardly while maintaining a horizontal posture as seen in FIG. 8.To the contrary, when the lifting plate 63 moves in the opposite or returning direction, the cassette holder 53 is moved downwardly while maintaining the horizontal posture until the tape cassette 60 within the cassette holder 53 is loaded onto a pair of reel receivers 68a and 68b (refer to FIGS. 1 to 4) and the capstans 40a and 40b as seen in FIG. 9.

The eject lever 54 and the cassette lifting plate 63 are associated with each other in such a relationship that, when the eject lever 54 is moved against the spring 64, an edge 70a of an opening 70 formed in the eject lever 54 pushes a bent lug 71 formed on the cassette lifting plate 63 to move the cassette lifting plate 63 against the spring 65.

The pivotal connecting plate 55 and the eject lever 54 are associated with each other in such a relationship that, when the cassette holder 53 is at its lowered position, an inclined edge 72 of the opening 70 of the eject lever 54 engages with a bent lug 73 formed at an end portion of a side wall of the pivotal connecting plate 55 so that the spring force of the tension coil spring 64 acts as a force to bias the pivotal connecting plate 55 in the downward direction.

Accordingly, the spring force of the spring 64 is utilized also as a force to hold the cassette holder 53 at the lowered position.

The spring receiving member 57 and the eject lever 54 are associated with each other in such a relationship that, when the eject lever 54 is pushed in against the spring 64 while the cassette holder 53 is held in the lowered position as shown in FIG. 9, the spring receiving member 5 is pivoted via the connecting link 61 to cause the toggle spring 58 to be turned over so that the spring force of the turn-over spring 58 thereafter acts as a cassette pushing back force upon the slider 56.

The arresting member 59 and the cassette lifting member 63 are associated with each other in such a manner that, when the cassette lifting plate 63 is moved against the tension coil spring 65, the arresting member 59 is engaged with an engaging tab 74 formed at an end of the lifting plate 63 to arrest the cassette lifting plate 63 from returning to its initial position. When the slide plate 56 is moved in the cassette inserting direction, the arresting member 59 is pushed to pivot by the slider 56 whereupon it is disengaged from the engaging tab 74 of the lifting plate 63.

With the tape feeding device having such a construction as described above, when the tape feeding device is in its rest condition, the cassette lifting plate 63 is arrested at its forwardly moved position by the arresting plate 59 wherein the guide projections 67 of the cassette holder 53 are positioned at the top horizontal portions of the inclined guideways 66 of the lifting plate 63 to hold the cassette holder 53 and the pivotal connecting plate 55 at their individual lifted positions as shown in FIG. 8. Further, the low speed rotation transmitting idler 33 and the high speed rotation transmitting idler 34 are both held in a spaced relationship from the reel gear members 32a and 32b as seen in FIG. 1, and hence the rotation transmitting routes from the motor 21 to the reel receivers 68a and 68b are in the cut condition.

Then, if a tape cassette 60 is inserted into the cassette holder 53, one of the reel holes of the cassette 60 is engaged with the slider 56, and then as the tape cassette 60 is moved further in the same direction, the slider 56 is pushed to move forwardly by the reel hole portion and the leading end portion of the tape cassette 60 while increasing the amount of resilient deformation of the toggle spring 58. Then, after turning over of the toggle spring 58, the tape cassette 60 is drawn to the end position into the inside of the cassette holder 53 by the spring force of the spring 58 whereupon the arresting member 59 is pushed to pivot by the slider 56 until the arresting member 59 is disengaged from the engaging tab 4 of the cassette lifting plate 63.

Consequently, the cassette holding plate 63 is moved back to its home position by the spring 65 while the guide projections 67 on the cassette holder 53 are slidably moved within the inclined guideways 66 of the cassette lifting plate 63 until the cassette holder 53 is moved down to the lowered position for recording or reproduction shown in FIG. 9.In the lower position, the cassette holder 53 is acted upon by the spring force of the spring 65 as a downward pressing force through engagement between the inclined guideways 66 of the cassette lifting plate 63 and the guide projections 67 on the cassette holder 53 while it is also acted upon by the spring force of the spring 64 as a downward spring force through engagement between the inclined edge 72 of the eject lever D4 and the bent lug 73 of the pivotal connecting plate 55.Upon such returning movement of the cassette lifting plate 63, the head mounting plate 37 is advanced from its rest position shown in FIG. 1 to its recording/reproducing position shown in FIG. 2 to move the magnetic head 36 into contact with a tape within the tape cassette 60 while one of the pinch rollers is pressed against the corresponding capstan 40b and the low speed rotation transmitting idler 33 is moved into simultaneous meshing engagement with the smaller diameter gear 28a and the forward side reel gear member 32b as seen in FIG. 2.

When the tape feeding device is in this condition, the turning force of the motor 21 is transmitted to the capstans 40a and 40b and also to the reel receiver 68b via the first friction transmission mechanism 1. Consequently, the tape held between the capstan 40b and the corresponding pinch roller is fed at a predetermined low speed and wound onto the forward side tape reel while recording on or reproduction from the tape is performed by the magnetic head 36 which is held in contact with the tape.

The magnetic tape is wound onto the forward side tape reel in this manner, and when it is completely wound up and comes to its extreme end, the tape end will be detected by a suitable detecting means which thus develops a tape end detection signal. In response to such tape end detection signal, the intermittent gear 39 is moved into meshing engagement with the tape feeding direction change-over driving gear 26. Consequently, the intermittent gear 39 is rotated by an angle of 180 degrees. The turning force of the intermittent gear 39 then is transmitted to slidably move the slide plate 38 in the leftward direction in FIG. 2. Consequently, the right-hand side pinch roller is spaced away from the capstan 40b while the left-hand side pinch roller is pressed against the capstan 40a.Upon such sliding movement of the slide plate 38, also the low speed rotation transmitting idler 33 is disengaged from the smaller diameter gear 28a integral with the low torque transmitting gear 28 and also from the forward side reel gear member 32b and now engaged with the smaller diameter gear 30a of the reversing gear 30 and the reverse side reel gear member 32a as seen in FIG. 3, thereby changing over the feeding direction of the magnetic tape to thereafter resume a recording or reproducing operation of the tape feeding device.

Subsequently, if, for example, the manually operable high speed reverse feeding member is manually operated to cause high speed feeding of the magnetic tape when a recording or reproducing operation is proceeding, the head mounting plate 37 is retracted by a predetermined amount to move the pinch roller away from the capstan and simultaneously move the low rotation transmitting idler 33 away from the smaller diameter gear 28a or 30a. Further, the feeding direction changeover plate 4D is moved in the rightward direction as seen in FIG. 4 to pivot the pivotal plate 41 in the counterclockwise direction whereupon the high speed rotation transmitting idler 34 is meshed with the smaller diameter gear of the reverse side reel gear member 32a and with the reversing gear 31.

When the tape feeding device is in this condition, the turning force of the motor 21 is transmitted at a high speed to the reel receiver 68a via the second friction transmission mechanism 52 so that the magnetic tape is fed and wound at a high speed onto the reverse side tape reel. Then, when the tape is fed at a high speed to its final end, the system from the high torque transmitting gear 29 to the reel receiver 68a is compulsorily stopped by tension of the tape, but the system from the motor 21 to the clutch gear 27 continues its rotation while yielding a slip in the direction of rotation in the second friction transmission mechanism 52, or more particularly, between the spring fingers 49a of the tripod spring plate 49 and the annular wall 29a of the high torque transmitting gear 29.

When this condition is reached, a tape end detection signal is developed as described above. In response to such tape end detection signal, an automatic stopping mechanism may be rendered operative, or else the tape feeding direction may be reversed to start a reproducing operation in the forward direction.

Description of such mechanisms, however, is omitted herein because they have no direct relation to the present embodiment.

On the contrary, if the manually operable high speed forward feeding member is manually operated to cause high speed feeding of the magnetic tape in the forward direction, the feeding direction change-over plate 45 is slidably moved in the leftward direction in FIG. 4 so that the high speed rotation transmitting idler 34 is meshed with the smaller diameter gear of the forward side reel gear member 32b and with the high torque transmitting gear 29 as indicated in phantom in FIG. 4 to drive the forward side reel receiver 68b to rotate at a high speed.

Subsequently, in order to end a recording or reproducing operation and take out the tape cassette 60, the eject lever 54 is moved in the forward direction against the tension coil spring 64.

Upon forward movement of the eject lever 54, the edge 70a of the opening 70 of the eject lever D4 pushes the bent lug 71 of the cassette lifting plate 63 to move the cassette lifting plate 63 in the forward direction against the spring 65. Accordingly, the guide projections 67 provided on the cassette holder 53 move upwardly in the inclined guideways 66 of the cassette lifting plate 63 so that the cassette holder 53 is moved upwardly while maintaining a horizontal posture.

Further upon forward movement of the eject lever 54, the spring receiving member 57 is pivoted in the direction to increase the amount of resilient deformation of the toggle spring 58. Then, after turning over of the toggle spring 58, the slider 56 is pushed back together with the tape cassette 60 by the spring force of the toggle spring 60. Such movement of the slider 56 starts at the same time with completion of the upward movement of the cassette holder 53 to enable removal of the tape cassette 60 from the cassette holder 53.

It is to be noted that the cassette lifting plate 63 having been pushed to move forwardly to its forwardly moved position is thereafter held at the forwardly moved position through engagement of the arresting member 59 with the engaging tab 74 of the cassette lifting plate 63. In this instance, the guide projections 67 on the cassette holder 53 are positioned at the top end horizontal portions of the inclined guideways 66 of the cassette lifting plate 63 so that the cassette holder 53 is held at its lifted position shown in FIG. 8.

With the tape feeding device having such a construction as described above, when a tape is to be fed at a predetermined low speed for recording or reproduction, the turning force of the motor 21 is transmitted to the reel receiver 68a or 68b by way of the first friction transmission mechanism 51, but when the tape is to be fed at a high speed, the turning force of the motor 21 is transmitted to the reel receiver 68a or 68b by way of the second friction transmission mechanism 52.

Accordingly, the rotation transmitting forces of the first and second friction transmission mechanisms 51 and 52 can be freely set independently of each other.

As a result, a spring having a weak spring force may be used as the coil spring 48 so as to reduce the turning force of the low torque transmitting gear 28 while another spring having a strong spring force may be used as the tripod spring plate 49 so as to increase the turning force of the high torque transmitting gear 29 to increase the turning force of the reel receiver 68a or 68b during feeding of a tape at a high speed. It will be appreciated that a spring member of the type which yields a spring force in a radial direction such as the tripod spring plate 49 used here is suitable as a spring to apply a high contact resistance to a rotary plate.

Meanwhile, it is not necessary to provide a friction transmission mechanism for each of a pair of left and right reel receivers as in the conventional arrangement shown in FIG. 12, and the first and second friction transmission mechanisms 51 and f2 are disposed in a concentrated manner at one location together with the clutch gear 27 and the two torque transmitting gears 28 and 29 provided in a coaxial relationship with the clutch gear 27. Accordingly, the number of parts can be reduced, and simplification in entire construction can be attained.

It is to be noted that while in the embodiment shown in FIGS. 1 to 9 the tripod spring 49 made of a thin steel plate is employed as a component or second spring member of the second friction transmission mechanism 52, it may otherwise be such a spring member as shown in either of FIGS. 10 and 11 in which second and third embodiments of the present invention are shown wherein construction of the friction transmission mechanism and associated parts is differentiated from each other and from that of the embodiment of FIGS. 1 to 9. It is to be noted that since the second and third embodiments of the present invention are basically similar in construction to the first embodiment, like parts or elements are denoted by like reference numerals to those of FIGS. 1 to 9, and overlapping description thereof is omitted herein to avoid redundancy.

Referring to FIG. 10, a second spring member 81 is formed from a corrugated thin steel band which is curved into a substantially annular ring. The second spring member 81 is accommodated in an annular groove 83 formed on a high torque transmitting gear 82 serving as a third rotary plate such that it may be resiliently pressed alternately against inner and outer circumferential walls of the annular groove 83 of the high torque transmitting gear 82. The second spring member 81 has a plurality of laterally extending projections 81a formed thereon which are fitted in a corresponding plurality of slits 85 formed in a clutch gear 84 serving as a first rotary plate so as to prevent rotation of the second spring member 81 relative to the clutch gear 84, thereby constituting a second friction transmission mechanism 86 for applying a contact resistance to the high torque transmitting gear 82.

With the tape feeding device of the second embodiment, the second spring member 81 having a substantially annular configuration can be pressed at a large number of locations against the inner and outer circumferential walls of the annular groove 83 of the high torque transmitting gear 82. Accordingly, the turning force of the high torque transmitting gear 82 can be further increased, and the turning force of the reel receiver upon high speed feeding of a tape can be increased readily. Further, also in the second embodiment, it can be freely made to decrease the rotation transmitting force of the first friction transmission mechanism 51 and increase the rotation transmitting force of the second friction transmission mechanism 86.

Referring now to FIG. 11, a clutch gear 91 serving as a first rotary plate and a shaft 92 for the clutch gear 91 are formed in an integral relationship, for example, by molding, or else the shaft 92 is secured to the clutch gear 91 by press fitting. A low torque transmitting gear 93 serving as a second rotary plate and a high torque transmitting gear 94 serving as a third rotary plate are mounted for rotation on the shaft 92 on the opposite sides of the first rotary plate 91.

A felt plate 95 and another felt plate 96 having a greater diameter than the felt plate 95 are interposed between the clutch gear 91 and the low torque transmitting gear 93 and between the clutch gear 91 and the high torque transmitting gear 94, respectively. The torque transmitting gears 93 and 94 are axially pressed against the clutch gear 91 by a pair of compression coil springs 97 and 98, respectively, which serve as first and second spring members, respectively. Here, the compression coil spring 97 has a smaller spring force than the other compression coil spring 98. Thus, a first friction transmission mechanism 99 can be constructed wherein a small turning force is applied to the low torque transmitting gear 93 by the coil spring 97 having a smaller spring force and a second friction transmission mechanism 100 wherein a great turning force is applied to the high torque transmitting gear 94 by the coil spring 98 having a greater spring force.

Similar effects to those of the first and second embodiments can be attained also by the tape feeding device of the third embodiment described just above.

Claims (5)

CLAIMS:

1. A tape feeding device of the type wherein a turning force of a motor is transmitted at a predetermined speed or a higher speed selectively to a pair of reel receivers, comprising a first rotary plate connected to receive the turning force of said motor, second and third rotary plates disposed in a coaxial relationship with said first rotary plate, first and second friction transmission mechanisms for transmitting the turning force of said first rotary plate to said second and third rotary plates, respectively, with different rotation transmitting forces, a low speed rotation transmitting idler operable for transmitting the smaller turning force of said second rotary plate selectively to said pair of reel receivers, and a high speed rotation transmitting idler operable alternatively to said low speed rotation transmitting idler for transmitting the greater turning force of said third rotary plate selectively to said pair of reel receivers.

2. A tape feeding device as set forth in claim 1, wherein said first friction transmission mechanism includes a first spring member for exerting an axial spring force to provide a contact resistance to said second rotary plate, and said second friction transmission mechanism includes a second spring member mounted against rotation relative to said first rotary plate and resiliently pressed in a radial direction against said third rotary plate to provide a contact resistance to said third rotary plate.

3. A tape feeding device as set forth in claim 2, wherein said second spring member of said second friction transmission mechanism has a substantially annular configuration and is accommodated in an annular groove formed on said third rotary plate such that it may be alternately pressed against inner and outer circumferential walls of said annular groove of said third rotary plate.

4. A tape feeding device as set forth in claim 1, wherein said first rotary plate is formed in an integral relationship with a shaft therefor while said second and third rotary plates are mounted for rotation on said shaft on the opposite sides of said first rotary plate, and said first and second friction transmission mechanisms includes first and second spring members, respectively, for resiliently pressing said second and third rotary plates, respectively, in axial directions against said first rotary plate.

5. A tape feeding device substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.