JPS62283437A - Reversing type recording and reproducing device - Google Patents

Abstract

PURPOSE:To ensure the changeover by using a couple of pickups for normal running and reverse running and allowing the pickup to detect the tape end and switch the tape running selectively. CONSTITUTION:In depressing a reproducing button 11 (recording button 12) to select the normal reproduction (recording) mode, a head base 13 is moved in the direction of arrow (a), the shaft pin 44 of the normal running pickup 40 is inserted into a recess 53 in such a case, a shaft pin 45 of the reverse running pickup 41 is removed from the recess 53, a holder 46 is shaken in the direction of arrow (h) in the notch 49 against a tensile spring 50, one pickup 40 is brought into contact with a magnetic tape 19 and the other pickup 41 is detached from the tape 19. When the mode reaches the tape end, the magnetic tape 19 is tensed and the pickup 40 pressed by the tension is driven in the direction of arrow f' in resisting to a tensile spring 47, a pressed part 56 is depressed by the pressing pin 54 and the mode is switched into the reverse by the drive of a missing gear 24 and a drive gear 31.

Description

[Detailed description of the invention] 3. Detailed description of the invention The present invention will be explained in the following order.

A. Field of industrial application B. Part 1 of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem F. Effect G. Embodiment G. Tape end detection mechanism and normal/reverse switching Description of the mechanism (Figs. 1 to 4) G2 Description of the manual switching mechanism for tape running (Figs. 3 and 4) G3 Description of the erasing head drive mechanism (Figs. 5 to 6C) G4 Stop eject Explanation of the normal priority mechanism at the time (FIGS. 7 to 8C) The present invention will be explained in detail in Section 01.

Effects of the Invention A: Industrial Field of Application The present invention is most suitable for application to, for example, reverse type tape recorders, and is capable of selectively running the tape at the end of the tape during normal tape running and reverse running. The present invention relates to a reverse type recording and reproducing device that switches to the reverse mode.

B. Summary of the Invention The present invention provides a reverse type recording and reproducing device that selectively switches the running of the tape at the end of the tape during normal running and reverse running. The end of the tape is detected by a pair of pickups for normal running or reverse running that are brought into contact with the tape, and the pickups are configured to perform a switching operation for selectively switching the running of the tape at the end of the tape. , the detection of the tape end and the subsequent switching of the tape running can be performed with an extremely simple structure and extremely reliably.

C. Conventional technology Conventionally, so-called auto-reverse tapes have been used, for example, in reverse-type tape recorders, to detect when the tape ends during normal running and reverse running, and selectively switch the running of the tape. There's a recorder.

In this case, conventionally, a sensor detects the stoppage of rotation of the reel stand due to the end of the tape, and a plunger triggers a switching mechanism for switching the running of the tape.
Alternatively, the stoppage of the rotation of the reel stand is detected by the reel stand drive rotating body that idles as the rotation of the reel stand stops, and a mechanical trigger is given to the switching mechanism by the interlocking mechanism.
It was designed to selectively switch the running of the tape at the end of the tape.

D Problems to be Solved by the Invention However, the conventional electrical configuration in which a sensor detects the stoppage of rotation of the reel stand and a plunger provides a trigger to the switching mechanism has a relatively small number of parts. Although the structure is simple, malfunctions are likely to occur, and the tape running mode is often not switched. On the other hand, a mechanical configuration using a reel table rotating body, an interlocking mechanism, etc. operates relatively reliably, but has the problem that the structure becomes extremely complicated.

SUMMARY OF THE INVENTION Accordingly, the present invention enables detection of a tape end and subsequent switching of tape running to be performed reliably with a simple structure.

E. Means for Solving Problems The present invention provides a switching rod that is moved between a normal position and a reverse position to selectively switch the running of the tape between normal running and reverse running, and a drive gear that intermittently moves the tape between normal running and reverse running. a toothless gear that is rotationally driven to move the switching rod; a lock plate that is configured to be reciprocally movable between a lock position and an unlock position and lock the toothless gear at a fixed position; a pair of pickups for normal running and for reverse running which are configured and in contact with the tape, and the pickup for normal running or reverse running is configured by moving the switching rod between the normal position and the reverse position. is selectively moved forward to make contact with the tape, and in this state, the tape end in normal running or reverse running is detected by the backward movement of the pickup due to tape tension, and the pickup at this tape end The lock plate is driven from the lock position to the lock release position by the backward movement of the lock plate to unlock the partially toothed gear.

The switching rod is moved by the rotational drive of the tape to selectively switch the running of the tape at the end of the tape.

F Function The present invention selectively moves the pick amplifier for normal running or reverse running forward and brings it into contact with the tape, so that when the tape becomes tense at the tape end, the pickup is moved backward, thereby causing the tape end to move forward. Detected.

By this return movement at the end of the tape, the lock plate that locks the partially toothed gear that moves the switching plate is driven from the lock position to the unlock position. Therefore, detection of the tape end and subsequent switching of tape running can be performed with an extremely simple structure and extremely reliably.

G. Embodiment Hereinafter, an embodiment in which the present invention is applied to an auto-reverse compact tape recorder using a compact cartridge will be described with reference to the drawings. This tape recorder can selectively switch the tape running between normal running and reverse running, and when normal running reaches the tape end, it automatically switches to reverse running, and when reverse running reaches the tape end, it automatically switches to reverse running. is shut off. Further, this tape recorder is constructed so that it always starts from normal running when a cassette is installed.

G. First, the tape end detection mechanism 1 and the normal/reverse switching mechanism 2 will be explained with reference to FIGS. 1 to 4.

In FIGS. 1 to 2C, a head substrate 13 is disposed on the chassis 10 of the tape recorder, and is moved forward in response to a pressing operation of a playback button 11 (recording button 12). A magnetic head 14, a pair of left and right pinch rollers 15 and 16, and the like are provided on the head substrate 13. As shown in FIG. 2B, in the normal mode, the head substrate 13 is moved slightly inclined in the direction of arrow a, and one pinch roller 15 is pressed against the capstan 17 provided on the chassis 10. Ru. Further, as shown in FIG.
8 is crimped. Then, the magnetic tape 19 is normally run in the direction of the arrow b' by the rotation drive device of the reel stand, or reversely run in the direction of the arrow b'.
Normal playback (recording) or reverse playback (recording) is performed.

Next, a switching rod 22 constituting the normal/reverse switching mechanism 2 is arranged at the bottom of the chassis 10. The other switching rod 22 is configured to be able to reciprocate in the directions of arrows C and e' between a normal position N shown in FIG. 2B and a reverse position R shown in FIG. 2C. A rectangular cam hole 23 is formed approximately in the center of the switching rod 22.
A cam 25 of a partially toothed gear 24 is engaged therein. That is, as shown in FIGS. 3 and 4, a partially toothed gear 24 constituting the normal/reverse switching mechanism 2 is rotatably supported by a shaft 26 below the switching rod 22. As shown in FIGS. and cam 25
is eccentrically formed integrally with the upper surface of the toothless gear 24 in a circular shape. In addition, a pair of toothless parts 27 and 28 are formed on the outer periphery of the toothless gear 24 with a bias of 180@, and these and 90
A pair of lock pawls 29 and 30 are integrally molded on the biased lower surface.The partially toothed gear 24 is configured to be driven to rotate intermittently in the direction of arrow d in FIG. 4 by a drive gear 31. Note that an initial rotational force in the direction of arrow d is applied to the partially toothed gear 24 by a spring 32.

Next, as shown in FIGS. 3 and 4, a lock plate 35 is provided below the partially toothed gear 24 for selectively locking the gear in the normal position and reverse position. This mouth
The pick plate 35 has its elongated hole 36 guided by the shaft 26 and the fourth
In the figure, it is configured to be able to reciprocate in the directions of arrows e and e', and is biased back in the direction of arrow e' by a return spring 37 stretched between it and the chassis 10. and lock plate 35
A lock portion 38 consisting of a protruding piece bent toward the partially toothed gear 24 side is formed at the partially toothed gear 24 .
Both lock claws 29 and 30 are configured to selectively abut.

Next, as shown in FIGS. 1 to 2C, the tape end detection mechanism 1 includes a pair of left and right pickups 40 that selectively contact the magnetic tape 19 depending on whether the magnetic tape 19 is running normally or in reverse. .41. That is, the pickup 40 for normal driving and the pickup 41 for reverse driving each have a substantially L-shaped arm 4.
2.43, both arms 42.43
The second
It is configured to be rotatable in the directions of arrows r, r' and g, g' in Figures A to 2C. Both pickups 40 and 41 are moved by arrows f and g by tension springs 47, respectively.
It is urged to rotate in the direction. Note that this rotation is caused by the holder 46
It is regulated by a pair of stoppers 48 provided at. The holder 46 is inserted into the notch 49 formed in the head substrate 13 below the magnetic helad 14 as shown in FIGS. 2B and 2.
In Figure C, it is loosely fitted so that it can swing in the arrow direction and i direction.

The holder 46 is moved forward by a tension spring 50 stretched between the holder 46 and the head substrate 13. Below the notch 49 of the head board 13, the switching rod 22 is provided with a recess 53 having a pair of left and right slopes 51.
4.45 is configured to be selectively inserted.

Further, pressing pins 54.55 projecting downward are integrally molded at the ends of both arms 42.43 of both pickups 40.41, and these press pins 54.55 are formed into a pressed portion 56, which is a protrusion formed on the lock plate 35. It is located on the front side.

Next, the tape end detection mechanism 1 configured as described above is
The operation and the normal/reverse switching mechanism 2 will be explained.

First, FIG. 2A shows the stop mode. Since the head substrate 13 is moved back in the direction of the arrow a'', the two shaft pins 44,45 of both the pickups 40,41 are spaced apart from the recess 53 of the switching rod 22.

The holder 46 is moved forward by the tension spring 50, and the double shaft pins 44, 45 are brought into contact with the rear edge 49a of the notch 49. And both pickups 40 and 41 are tension springs 4
7 to rotate in the directions of arrows f and g, and the rotation is restricted by both stoppers 48. Therefore, both pickups 40.degree. 41 are located symmetrically and spaced apart from the magnetic tape 19.

Next, as shown in FIG. 2B, the play button 11 (record button 1
When the mode is switched to the normal reproduction (recording) mode by pressing 2), the head substrate 13 is moved forward in the direction of arrow a. Here, since the switching rod 22 is in the normal position N moved in the direction of arrow C, the recess 53 of the switching rod 22 has also been moved in the same direction. Therefore, when the head board 13 is moved forward, the shaft pin 44 of the pickup 40 for normal running
is inserted into the recess 53, and the shaft pin 45 of the pickup 41 for reverse running is removed from the recess 53. As a result, the holder 46 resists the tension spring 50 and the notch 49
One pickup 40 is brought into contact with the magnetic tape 19, and the other pickup 41 is separated from the magnetic tape 19. In this state, both shaft pins 44 and 45 are attached to both side edges 4 of the notch 49 of the head board 13.
Since it is in contact with 9b and 49c, both pickups 4
Movement in the left and right direction of 0.41 is restricted.

Next, when the tape reaches the end in the above-mentioned normal playback (recording) mode, the magnetic tape 19 is pulled, and the pickup 40 is pushed by the tension and moves in the direction of the arrow r', against the tension spring 47, as shown by the dashed line. is rotated. The pressing pin 54 of the arm 42 is also rotated. Then,
In FIG. 4, the pressed portion 56 of the lock plate 35 is pressed by the pressing pin 54, and the lock plate 35 is moved forward in the direction of arrow e against the return spring 37. As a result, lock plate 3
5 escapes from the lock pawl 29 at the normal position of the toothless gear 24, the toothless gear 24 is rotated in the direction of arrow d by the initial rotational force of the spring 32, and the drive gear 31
is engaged with. The partially toothed gear 24 is driven by the drive gear 31 by half a rotation in the direction of the arrow d.

Then, by driving the partially toothed gear 24 by half a rotation, the cam 25 of the partially toothed gear 24 is driven within the cam hole 23 of the switching rod 22, and the switching rod 22 is reversed in the direction of arrow e' as shown in FIG. 2C. It is moved to position R. This switches the normal playback (recording) mode to the reverse playback (recording) mode.

By this movement of the switching rod 22, the pickup 40 for normal running is separated from the magnetic tape 19, and the pickup 41 for reverse running is brought into contact with the magnetic tape 19. That is, as the switching rod 22 moves in the direction of arrow e', the recess 53 is also moved in the same direction, so the shaft pin 44 of one pickup 40 is removed from the recess 53 along the slope 51, and the other pickup 40 is removed from the recess 53 along the slope 51. The shaft pin 45 of the pickup 41 is inserted into the recess 53 along the slope 52. As a result, the holder 46 is swung in the direction of arrow i against the tension spring 50, and one pickup 40 is separated from the magnetic tape 19 while the other pickup 41 is brought into contact with the magnetic tape 19. In addition, at this time, the movement of both pickups 40 and 41 in the left and right direction is due to the movement of both pickups 40 and 41.
4.45 is regulated by coming into contact with both side edges 49b and 49C of the notch 49.

Note that by switching both the pickups 40 and 41, the lock plate 35 is pressed by the pressing pin 54 of the pickup 40.
Since the pressure on the lock plate 35 is released, the lock plate 35 in FIG.
is moved back in the direction of arrow e' by the return spring 37. Therefore, the toothless gear 24 is driven half a rotation, and with the drive gear 31 facing the toothless portion 28 in the reverse position, the lock pawl 30 in the reverse position is brought into contact with the locking portion 38 of the lock plate 35. Locked in reverse position.

Next, when the tape end is reached in the reverse playback (recording) mode in FIG. ’ direction. The pressing bottle 55 of the arm 43 is also rotated. Then, as shown in FIG.
The pressed portion 56 is pressed, and the lock plate 35 is moved in the direction of arrow e.
The partially toothed gear 24 is unlocked at the reverse position. As a result, the partially toothed gear 24 is again driven half a rotation in the direction of the arrow d. During this half-rotation drive, the shaft is turned off by a shaft-off mechanism (not shown), and the head substrate 13 is moved back in the direction of arrow a# as shown in FIG. 2A, thereby entering the stop mode. Note that the switching rod 22 is moved to the normal position N again by the half-rotation drive of the partially toothed gear 24.

G2 Next, the manual switching mechanism 3 for tape running will be explained with reference to FIGS. 3 and 4.

First, a switching operation plate 60 is arranged below the lock plate 35. This switching operation plate 60 has long holes 61 and 6.
2 is guided by shafts 26 and 63 so as to be able to reciprocate in the directions of arrows j and j' in FIG.
A return spring 64, which is stretched between , is biased backward in the direction of arrow j'. Then, the switching operation plate 60 is formed with an engaging part 65 made of a long hole, and an engaged part 66 made of a protrusion formed on the locking plate 35 is inserted into the engaging part 65. . Note that a push button 67 is attached to the switching operation plate 60.

According to the manual switching mechanism 3 configured as described above, when the push button 67 in FIG. 4 is pressed and the switching operation plate 60 is moved forward in the direction of arrow j against the return spring 64, the retaining portion 65
The engaged portion 66 of the lock plate 35 is pressed by the one end 65a, and the lock plate 35 is moved forward in the direction of arrow e against the return spring 37. Then, the partially toothed gear 24 is unlocked as explained in the above section 02. Therefore, the running of the magnetic tape 19 can be arbitrarily switched from normal running to reverse running by manual operation.

03 Next, the erasing head drive mechanism 4 will be explained with reference to FIGS. 5 to 6C.

A pair of erasing heads 70.71 for normal running and reverse running are arranged on both sides of the pinch roller 16.15 on the chassis 10.

Both erase levers 70 and 71 are erase levers 72.
, 73, and both these erasers 72 and 73 are rotated in the directions of arrows k, k', l, and 1' in FIGS. It is freely supported and biased to rotate in the directions of arrows k and l by tear springs 76 and 77. Pins 78 and 79 that penetrate the chassis 10 and project downward are integrally molded on both the eraser levers 72 and 73, respectively. Note that an engagement hole 80 is formed in the erasing head lever 73 for reverse running.

Next, a recess 84 having a slope 83 is formed in one end 22a of the switching rod 22, and the pin 78 of the erasing lever 72 is inserted into the recess 84. Further, a recess 86 having a slope 85 is formed in the other end 22b of the switching rod 22, and the pin 79 of the 7-drive lever 73 is inserted into the recess 86.

Next, the recording button 12 is attached to the tip of a recording operation rod 90. As shown in FIGS. 6A to 6C, this recording operation rod 90 is configured to be able to reciprocate in the directions of arrows m and m' at the bottom of the chassis 10, and is actuated by a return spring 91 as shown in arrow m'.
It is biased backward in the direction. The 91i working rod 90 is provided with an inclined crank-shaped cam groove 92. Further, a protrusion 93 is formed on the recording operation rod 90, and this protrusion 93
The pin 78 of the erasing sleeve 72 is brought into contact with the eraser.

A control rod 94 is provided on the front end side of the chassis 10.
As shown in FIGS. 6C to 6C, it is arranged so as to be able to reciprocate in the directions of arrows n and m', and is biased back and forth in the direction of arrow n' by a return spring 95. Then, a protrusion 96 formed at one end of the control rod 94 is engaged with the cam groove 92 of the recording operation rod 90, and a protrusion 97 formed at the other end of the control rod 94 is moved to the erasing lever 73.
is inserted into the engagement hole 80 of.

In addition, in FIGS. 6A to 6C, 101 is a regeneration operation rod, and the regeneration phase 11 is attached to the tip thereof. The regeneration operation rod 101 is configured to be able to reciprocate in the directions of arrows q and q', and is biased back in the direction of arrow q' by a return spring 102. Further, 103 is a tension spring that is stretched between the reproduction operation rod 101 and the head substrate 13 and moves the head substrate 13 forward, and 104 locks the recording operation rod 90, the reproduction operation rod 101, etc. in the forward movement position. It is a rock board.

Next, the operation of the erasing head drive mechanism 4 configured as described above will be explained.

First, FIG. 6A shows the stop mode, in which the recording operation rod 90 is moved back in the direction of the arrow m', so the protrusion 93 of the recording operation rod 90 moves the erase lever 72.
The pin 78 is regulated, and the lever 72 is moved back in the direction of the arrow ' to erase it. Also, since the projection 96 of the control rod 94 is guided by one end 92a of the cam groove 92 of the recording operation rod 90, the control rod 94 is moved back in the direction of the arrow n', and the projection 97 of the control rod 94 erases data. The paddle lever 73 is moved back in the direction of arrow L''.

Even if you switch to playback mode in this state, the recording operation lever 90
is not moved forward, so the switching rod 22 moves in the direction of arrow C or C''
Even if the direction is moved to switch between normal playback and reverse playback, both erase head levers 72 and 73 are in the backward movement position, and these erase heads 70 and 71 are not connected to the magnetic tape 1.
It is separated from 9.

Next, as shown in FIG. 6B, when the recording operation rod 90 is moved forward in the direction of arrow m in the normal mode and switched to the normal recording mode, the rad lever 72 is moved to erase by the protrusion 93 of the recording operation rod 90. The restriction on pin 78 is released. At this time, the switching rod 22 is moved in the direction of arrow C, so
Rad lever 72 to erase from recess 84 in one end 22a.
The pin 78 is removed, and the erase head lever 72 is rotated in the direction of the arrow by the torsion spring 76, so that the erase head 7
0 is brought into contact with the magnetic tape 19. On the other hand, the recording operation rod 9
The forward movement of the control rod 94 guides the protrusion 96 of the control rod 94 toward the other end 92b of the cam groove 92, and the control rod 94 is moved forward in the direction of arrow n.

As a result, the restriction of the erasing lever lever 73 by the protrusion 97 of the control rod 94 is released, but since the pin 79 of the driver lever 73 has been disengaged from the recess 86 of the switching rod 22, the erasing head lever 73 is It is restricted to rotate in the direction of arrow p'.

Next, as shown in FIG. 6C, when the reverse recording mode is switched, the pin 78 of the erase lever 72 moves along the slope 83 of the switching rod 22 as the switching rod 22 moves in the direction of arrow C'. The erase head 70 is inserted into the recess 84, and the erase head lever 72 is rotated in the direction of the arrow '', thereby separating the erase head 70 from the magnetic tape 19. On the other hand, the pin 79 of the erasing head lever 73 is inserted into the recess 86 along the slope 85, and the erasing head lever 73 is aligned with the arrow! The erasing head 71 comes into contact with the tape 19 with force<+n.

G4 Next, the normal priority mechanism 5 at the time of stop/eject will be explained with reference to FIGS. 7 to 8C.

First, as shown in FIGS. 8A to 8C, the chassis lO
At the bottom on one side, a stop operation lever 108 is indicated by arrows p and p'.
It is arranged so as to be able to reciprocate in the direction of the arrow p', and is biased back in the direction of the arrow p' by a return spring 109. A stop button 110 is attached to the tip of the stop operation rod 108, and an eject operation protrusion 111 for operating a cassette eject mechanism (not shown) and a protrusion 112 for operating a control lever 116, which will be described later, are attached to the side. , and a lock release protrusion 113 for operating the lock plate 104.

A connecting lever 114 having an L-shape is supported above the stop operation lever 108 so as to be rotatable in the directions of arrows q and q' by using the support shaft 74 of the eraser lever 72. A control lever 116 is supported at one end of the connecting lever 114 via a support shaft 115 so as to be rotatable in the directions of arrows r and r', and is urged to rotate in the direction of arrow r by a return spring 117. The control lever 116 is provided at its tip with a protrusion 119 pressed by a switch operating plate 118 arranged to overlap with the lock plate 104 and a protrusion 120 pressed by a protrusion 112 of the stop operation rod 108. There is.

Note that the switch operating plate 118 operates a power switch (not shown). Further, a protrusion 121 is formed at the other end of the control lever 116, and the protrusion 121 is configured to be pressed by a protrusion 122 provided at one end 22a of the switching rod 22.

Next, an engagement hole 123 is formed at the other end of the connection lever 114, and a protrusion 125 provided at one end of the connection rod 124 is engaged within this engagement hole 123. This connecting rod 124 is connected along the front end side of the chassis IO with arrows S and S.
'It is arranged so that it can freely reciprocate in the force direction. and connecting rod 1
The other end of 24 extends to the vicinity of the partially toothed gear 24, and a protrusion 131 of a switching plate 130 is engaged in a retaining hole 126 provided at the other end. As shown in FIG. 7, this switching plate 130 has a substantially L-shape, and is connected to the shaft 26 between the locking plate 35 and the switching operation plate 60 as shown in FIGS.
It is rotatably supported in the force direction indicated by the arrow L' in FIG. 8C. A protrusion 132 is formed at the other end of the switching plate 130, and this protrusion 132 is connected to an engagement hole 132 formed in the switching operation plate 60.
is engaged within.

Next, the operation of the normal priority mechanism 5 configured as described above at the time of stop/eject will be explained.

First, FIG. 8A shows the normal playback (recording) mode, in which the switch operation plate 118 that is linked to the forward movement of the playback operation rod 101, the recording operation rod 90 (see FIGS. 6A to 6C), etc. The protrusion 119 of the control lever 116 is pressed, and the control lever 116 is rotated in the direction of arrow r against the return spring 117. Further, since the switching operation plate 60 is moved back in the direction of arrow J' by the return spring 64, the switching plate 130 is rotated in the direction of arrow L' through the engagement hole 133 and the protrusion 132. As a result, the switching plate 130
The connecting rod 124 is moved back in the direction of the arrow S' through the protrusion 131, and the connecting lever 114 is rotated in the direction of the arrow q' by the protrusion 125 of the connecting rod 124. Therefore, the control lever 116 is rotated in the direction of arrow R, and the control lever 116 is rotated in the direction of arrow U.
’ direction.

Here, when the stop button 110 is pressed and the stop operation rod 108 is moved forward in the direction of arrow p, the lock release protrusion 113 of the stop operation rod 108 is activated by the slope 104a of the lock plate 104.
is pressed, the lock plate 104 is moved, and the playback operation lever 101 and the recording operation lever 90 are unlocked to enter the stop mode (see FIG. 6A). Note that the switch operating plate 11
8 is also moved at the same time as shown by the dashed line. Then, when the stop button 110 is pressed again and the stop operation rod 108 is moved forward in the direction of the arrow p, the cassette eject mechanism a is operated by the eject operation projection ill of the stop operation rod 108, and the cassette is ejected. However, at this time, since the mode is normal mode, the switching rod 22 has been moved in the direction of arrow C, and the protrusion 122 is in contact with the control lever 116.
protrudes to the side. Therefore, the protrusion 121 of the control lever 116 is restricted by this protrusion 122, and the control lever 1
16 is held in a rotated state in the direction of arrow r.

Therefore, even if the stop operation rod 108 is moved forward in the direction of the arrow p for the second time, the protrusion 112 of the stop operation rod 108 does not press the protrusion 120 of the control lever 116, and the control lever 11
6 is not operated at all. Therefore, the normal mode is maintained as it is, and when the cassette is loaded again after the cassette is ejected, recording or playback is performed again in the normal mode.

Next, FIG. 8B shows a state in which the stop button 110 is pressed once in the reverse mode to switch to the stop mode.

At this time, since the mode is reverse mode, the switching rod 22 is moved in the direction of arrow C', and its protrusion 122 is separated from the control lever 116. Therefore, when the switch actuating plate 118 releases the pressure on the protrusion 119 of the control lever 116, the control lever 116 is released by the return spring 117.
The control lever 116 is rotated in the direction of the force indicated by the arrow r', and the protrusion 120 of the control lever 116 is inserted into a position in front of the protrusion 112 of the stop operation lever 108.

Here, as shown in FIG. 8C, when the stop button 110 is pressed again and the stop operation rod 108 is moved forward in the direction of arrow p, the eject operation protrusion 111 of the stop operation rod 108 is moved forward.
At the same time as the cassette is ejected, the protrusion 120 of the control lever 116 is pressed by the protrusion 112, and the control lever 116 is pulled up in the direction of arrow U. As a result, the connecting lever 114 is rotated in the direction of the arrow q, and the connecting rod 124 is moved forward in the direction of the arrow S through the engagement hole 123 thereof. Then, the switching plate 130 is rotated in the direction of the arrow, and the switching operation plate 60 is moved forward in the direction of the arrow j via the projection 132 and the engagement hole 133. As a result, the partially toothed gear 24 is unlocked in the reverse position as explained in the above-mentioned sections G, , and G. In this manner, in the reverse mode, after switching to the stop mode by pressing the stop button 110 for the first time, the cassette is ejected by pressing the stop button 110 for the second time, and at the same time, a return to the normal mode is performed. Therefore, when the cassette is loaded again after being ejected, recording or playback is performed in the normal mode.

In reality, after the next cassette is loaded, the partially toothed gear 24 is driven half a rotation at the start of recording or playback to switch to the normal mode.

Although one embodiment of the present invention has been described above, the present invention is not limited to the embodiment, and various effective changes can be made based on the technical idea of the present invention.

For example, in the embodiment, a pair of arms of a pair of pickups are rotatably supported on a holder, and this holder is swingably attached to a head board, and a pair of shaft pins of both arms are inserted into and removed from a recess in a switching rod. As a result, both pick amplifiers are configured to selectively reciprocate, so the switching structure for both pick amplifiers is extremely simple and the operation is extremely smooth, but the shape and structure of these can be changed in various ways. It is possible.

Note that the present invention is not limited to auto-reverse type compact tape recorders using compact cassettes, but can be applied to various types of reverse type recording and reproducing devices.

Effects of the invention In the present invention, the tape end is detected by a pair of pickups for normal running and reverse running, and the switching operation for selectively switching the tape running is performed by the pick amplifier. The electrical configuration that uses sensors and plungers to detect the stoppage of rotation of the tape does not increase the number of malfunctions, and the mechanical configuration that uses the reel table rotating body and interlocking mechanism makes the structure extremely complicated. End detection and subsequent switching of tape running can be performed with a simple structure and extremely reliably. Therefore, not only can credibility be significantly improved, but also miniaturization of tape recorders and the like can be greatly promoted.

[Brief explanation of drawings]

The drawings show an embodiment in which the present invention is applied to an auto-reverse compact tape recorder using a compact cartridge. FIG. 3 is an exploded perspective view of the normal/reverse switching mechanism and manual switching mechanism as seen from the bottom side; FIG. 4 is a bottom view of the same; FIG. 5 is an exploded perspective view of the erasing head drive mechanism; Figures 6A to 6C
FIG. 7 is an exploded perspective view of the normal priority mechanism, and FIGS. 8A to 8C are plan views of the same as above. In addition, in the symbols used in the drawings, 1.--.----.--..--.-Tape end detection mechanism 2.--.--Normal/reverse switching mechanism. 13-----1・・--1----
-Head board 19----Magnetic tape 22-----------Switching rod 24-------- -1・−・−・・Gear with missing teeth 29.
30--...-1--Lock claw 31--...
−・−・・～・Drive gear 35−・−・−・−・・
-1--Lock plate 38---1---Lock portion 40.41----Pickup 42.43-----1- -・Arm 44.45・
-・・・・Axle bottle 46 − ・−・−・・・・・・Here holder 47～・・
−・−・・・−−−−−−−−・Tension spring 49...
・−・−−−−−−−−−m-notch part 50−・−・−
−〜−−・−・−−−〜−Tension spring 53−−−−−−・
−・・−・−・−Recessed portion 54.55−−−−−−1・・
・−8 Pressure bottle 56・−m−−−−−−・−・〜・−
・It is a pressed part.

Claims (1)

[Scope of Claims] A switching rod that is moved between a normal position and a reverse position to selectively switch the running of the tape between normal running and reverse running, and a switching lever that is intermittently rotationally driven by a drive gear. a lock plate that is configured to be reciprocally movable between a lock position and a lock release position and lock the partially toothed gear at a fixed position; and a lock plate that is configured to be reciprocally movable and contact the tape. a pair of pickups for normal running and for reverse running, and the pickup for normal running or reverse running is selectively moved forward by moving the switching rod between the normal position and the reverse position. The tape is brought into contact with the tape, and in this state, the end of the tape in normal running or reverse running is detected by the backward movement of the pickup due to the tension of the tape, and the backward movement of the pickup at the tape end causes the locking plate to close. is driven from a locking position to an unlocking position to unlock the partially toothed gear, and the rotation of the partially toothed gear moves the switching rod to selectively switch the running of the tape at the end of the tape. A reverse type recording/playback device.