JPS6288163A - Auto reverse type recording and reproducing device - Google Patents

Abstract

PURPOSE:To automatically shut-off the titled device when switching a normal running to a reverse running, in case a claw for a B face does not exist, by detecting by a detecting lever for the B face whether the claw for the B face exits or not, when switching the normal running to the reverse running, and switching a shut-off mechanism to a state of non-operation/operation in accordance with whether the claw for the B face exists or not. CONSTITUTION:When a control lever 210 is oscillated in the direction as indicated with an arrow D' from a state as shown in the figure, in which a switching lever is moved to a reverse position, one end edge 204a of a long hole 204 of a detecting lever 190 for an A face is pressed by a pin 211 of the lever 210, and the detecting lever 190 is brought to a forward motion in the direction as indicated with an arrow B and controlled at a lock release position. On the other hand, a detecting lever 191 for a B face is not controlled by the pin 211 of the control lever 210 but made to be able to execute a reciprocating motion between arrows C, C'. Accordingly, when the switching lever is in the reverse position, the detecting lever 191 for he B face detects independently a claw for the B face, and when the claw 174 for the B face does not exist, the detecting lever 191 is brought to a backward motion at a lock position in the direction as indicated with the arrow C' by a spring 197.

Description

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

A. Field of industrial application B. Overview of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem F. Effect G. Embodiment G1 Overview of operation of tape running drive system and tape recorder Explanation (Fig. 1 to Fig. 3) Explanation of 62 normal/reverse switching device (Fig. 1 to Fig. 4)
Figures to Figures 6C) G3 Explanation of the head support mechanism (Go to Figures 7 and 8B) G4
Explanation of the trigger mechanism (Fig. 1, Fig. 9A to Fig. 10) Explanation of the G5 shutoff mechanism (Fig. 1, Fig. 11A to Fig. 11D) G. Description of the mode switching mechanism (Fig. 1, Fig. 11A) Figure ~ 1st
(Fig. 1D) Explanation of G, normal, reverse switching means (Fig. 1,
1A to 11D) Explanation of the G8 recording switching mechanism (Fig. 1, 12 to 13C)
G7 Description of the recording shutoff mechanism which is the main part of the present invention (FIGS. 1, 12, 14A to 14F) G1 Description of the mode switching mechanism in the recording mode (FIGS. 1, 14F)
14A to 14F) Description of normal/reverse switching means in GI+ recording mode (Fig. 1, 14A to 14F) Description of GI2 erase head drive mechanism (Fig. 1, 15 to 14F)
Figure 16B) H Effect of the Invention A Industrial Application Field The present invention is most suitable for application to, for example, a tape recorder, and is capable of switching the tape running from normal running to reverse running. This invention relates to an auto-reverse recording and reproducing device.

B. Invention (Existing Invention) The present invention is an auto-reverse type recording and reproducing device that is capable of switching the running of a tape from normal running to reverse running. The presence or absence of the two accidental erasure prevention claws for normal driving and reverse driving is determined for A side and B side.
Detected independently from each other by two detection rods for the surface,
When switching from normal driving to reverse driving, the B-side detection rod detects the presence or absence of the B-side pawl, and depending on the presence or absence of the B-side pawl, the shy I/off mechanism is set in the inactive state and in the activated state. By switching to , it is possible to automatically shut off when switching from normal driving to reverse driving when there is no pawl for the B side.

C. Conventional technology As is well known, in a tape recorder having a recording function, a detection mechanism detects the presence or absence of an accidental erasure prevention claw provided on the tape cassette to be loaded, and only when the claw is present, the recording mode is activated. It is possible to switch to.

By the way, even in auto-reverse type tape recorders, etc., which are capable of switching the tape running from normal running to reverse running, the two claws for side A and side B of the tape cassette are There was only one nail detection pattern for side A. When the tape cassette to be loaded has a claw for the A side, it is possible to record in reverse running following normal running even if there is no claw for the B side.

-D Problems to be Solved by the Invention As mentioned above, in the past, the structure was such that only the claw for the A side of the tape cassette to be installed was detected, so the normal running If it was possible to record in reverse mode, it was possible to record in reverse mode following normal mode, regardless of the presence or absence of the B-side pawl. Therefore, even if the claws for the B side were removed, normal running would automatically switch to reverse running, resulting in the inconvenience that double recording would occur unexpectedly during reverse running. For this reason, if you do not want to record during reverse driving, you must be very careful about ending the recording during normal driving, which is extremely troublesome during recording.

Therefore, the present invention makes it possible to automatically switch to reverse driving when there is a pawl for the B side when switching from normal driving to reverse driving, and to automatically shut off when the pawl is not present. It is.

E. Means for Solving Problems The present invention provides a reciprocating recording operation rod that switches from a stop mode to a recording mode by being moved from a backward position to a forward position, and a recording operation rod that switches between a normal position and a reverse position. a switching rod that is moved between positions to selectively switch the running of the tape between normal running and reverse running, and a tape cassette for side A and side B that is controlled by this switching rod and provided on the tape cassette to be mounted. The two detection rods for the A side and the B side are reciprocated independently depending on the presence or absence of the two accidental erasure prevention claws, and the reciprocating movement of the detection rod for the B side allows the inactive state and the activated state to be determined. and a shutoff mechanism that performs a shutoff operation when switching from normal driving to reverse driving in the operating state, and in the recording mode when the recording operation rod is moved to the forward position, the shutoff mechanism is switched from normal driving to reverse driving. When switching to reverse running, the switching rod is moved to the reverse position, so that the detection rod for side B detects the presence or absence of the claw for side B of the tape cassette, and if the claw is present, the shutoff is activated. The shut-off mechanism is not operated, and the shut-off mechanism is switched to the operating state by the B-side detection rod to perform the shut-off operation only when the claw is absent.

F Function According to the present invention, when the switching lever is moved to the reverse position when switching from normal running to reverse running in the recording mode, the switching lever controls the detection lever for side B so that it can reciprocate. In this state, if there is a claw for side B of the tape cassette, the detection rod for side B is moved forward and the shutoff mechanism is switched to a non-operating state, and the shutoff operation is not performed and reverse running is automatically performed. can be switched to

On the other hand, if there is no pawl for the B side, the detection rod for the B side is moved back, the shutoff mechanism is switched to the operating state, and the shutoff operation is automatically performed.

G. Embodiment Hereinafter, an embodiment in which the present invention is applied to an auto-reverse compact tape recorder using a compact cassette will be described with reference to the drawings.

G1 First, the tape running drive system and the general operation of the tape recorder will be explained with reference to FIGS. 1 to 3.

FIG. 2 shows the tape running drive system of this tape recorder, in which a cassette 4 containing a magnetic tape 3 wound around a pair of left and right reel hubs 1.2 is mounted on a chassis 6.
It is mounted horizontally on the top of the

A pair of left and right reel stands 7.8, a capstan 9.10, a pinch roller 11.12, a magnetic head 13, etc. are provided on the upper part of the chassis 6, and a reel hub l of the cassette 4 mounted on the chassis 6, 2 is engaged with the reel stand 7.8, and the magnetic tape 3 is passed onto the capstan 9.10 and the magnetic head 13. Note that mode switching buttons such as a record button 15, a play button 16, a stop phase 17, a fast forward button 18, and a rewind button 19 are attached to the front surface of the chassis 6.

Next, as shown in FIGS. 2 and 3, at the bottom of the chassis 6, there is a flat and thin motor 21 installed coaxially with the reel stand 8, and a cap fixed to the lower end of the capstan 9 and 10. Capstan pulley 22.23, which also serves as a stand flywheel, intermediate boot IJ 24 installed approximately in the middle of reel stand 7.8, capstan pulley 2
A reversing pulley 25 is provided, which is arranged in one example of the third part. An elastic heald 27 is wound between each of these pulleys 22, 23, 24, 25 and the drive pulley 26 of the motor 21.

On the other hand, the reel stand 7 attached to the upper part of the chassis 6
．． A reel stand gear 30.31 is formed on the outer periphery of the reel stand 7.8, and an FR first idle gear 33 and F
An R second idle gear 34 is provided. Further, an NR idle gear 35 and an intermediate gear 36 for normal running and rehearsing running of the magnetic tape 3 are provided in the middle of the reel stand 7.8. Further, a partially toothed gear 37 for switching the magnetic tape 3 between normal running and reverse running, and a drive gear 37 for intermittently rotating the gear are attached to the lower part of the chassis 6.

This tape recorder has a record button 15 and a playback button 1.
6. When the fast forward sum 18 and rewind buttons 19 are pressed, a power switch (not shown) is turned on, the motor 21 is rotated at a constant speed, and its drive boob IJ 26 is rotated in the direction of arrow a in FIG. The intermediate pulley 24 and capstan pulleys 22 and 23 are configured to be rotationally driven in the directions of arrows A, C, and D, respectively.

When the fast forward button 18 is pressed, a fast forward/rewind switching mechanism (not shown) causes the FR drive gear 39 formed on the outer periphery of the intermediate pulley 24 to be set to the FR first idle position, as shown by the solid line in FIG. While the gear 33 is engaged, this F
The FR second idle gear 33 is always engaged with the R first idle gear 33.
Idle gear 34 is the reel stand gear 3 of one reel stand 7
0 selectively engaged. As a result, one reel stand 7 is driven to rotate at high speed in the direction of arrow e, and a fast-forward mode is entered in which the magnetic tape 3 is run in the direction of arrow f and wound around one reel hub 1 at high speed.

On the other hand, when the rewind button 19 is pressed, the PR first idle gear 33 is selectively engaged with the FR drive gear 39 and the reel stand gear 31 of the other reel stand 8, as shown by the dashed line in FIG. Ru. As a result, the other reel stand 8 is driven to rotate at high speed in the direction of arrow g, and a rewinding mode is entered in which the magnetic tape 3 is run in the direction of arrow f' and wound onto the other reel hub 2 at high speed.

Next, when the regeneration button 16 is pressed, the NR is provided on the same axis as the intermediate pulley 24 and is driven to rotate in the same direction as the intermediate pulley 24 via a torque limiter (not shown).
NR idle gear 3 constantly engaged with drive gear 40
5 is selectively engaged with the intermediate gear 36, which is always engaged with the reel stand gear 30 of one reel stand 7, by a normal/reverse switching device 45, which will be described later, as shown by the solid line in FIG. . At the same time, the magnetic head 13 is brought into contact with the magnetic tape 3 by a head support mechanism 46 to be described later, and the pinch roller 11 is attached to one capstan 9.
is crimped. As a result, one reel stand 7 is
The magnetic tape 3 is driven to rotate in the direction of the arrow f and is wound on one of the rolling hubs 1 in a normal reproduction mode, and the magnetic head 13 performs normal reproduction.

When the normal running of the magnetic tape 3 reaches the end of the tape, a trigger mechanism 47 (to be described later) is activated by a drive gear 38 which is constantly rotated integrally with the intermediate gear 42 by the integral drive gear 41 in the same axis as the intermediate boolean IJ24. As a result of the operation, the partially toothed gear 37 is selectively engaged, and the partially toothed gear 37 is driven half a rotation. Then, the normal/reverse switching device 45 is driven to switch to reverse driving. By this switching, the NR idle gear 35 is selectively engaged with the reel stand gear 31 of the other reel stand 8 as shown by the dashed line in FIG. 3, and the pinch roller 12 is pressed against the other capstan 10. Ru. As a result, the other reel stand 8 is rotationally driven in the direction of the arrow g, the magnetic tape 3 is run in the direction of the arrow f' and is wound on the other reel hub 2, entering the reverse reproduction mode, and the magnetic head 13
Reverse playback is performed.

In addition, this tape recorder has a recording function, and has two sides, one for side A and one for side 8, provided on the cassette 4 to be loaded.
The presence or absence of the two accidental erasure prevention claws 173 and 174 is detected independently from each other by a recording switching mechanism 172, which will be described later, and by pressing the recording button 15, normal and reverse recording is performed in the same manner as the above-mentioned normal and reverse reproduction. In the recording mode, two erasing heads 177 and 178 for normal running and reverse running are brought into selective contact with the magnetic tape 3 by an erasing head drive mechanism 176, which will be described later.

Note that when the stop button 17 is pressed in fast forward, rewind, playback, or recording modes, the power switch is turned off and the rotation of the motor 21 is stopped, and as shown in FIG. The idle gears 33, 34 or NR idle gear 35 are returned to the neutral position and enter the stop mode.

By the way, this tape recorder is configured so that when the magnetic tape 3 reaches the tape end during reverse running, a shutoff operation is performed by a shutoff mechanism 48, which will be described later, and the tape recorder automatically enters a stop mode. Further, this tape recorder has a reciprocating mode in which the magnetic tape 3 is stopped after normal running followed by reverse running, and a reciprocating mode in which the magnetic tape 3 is repeatedly switched between normal running and reverse running by a mode switching mechanism 49 to be described later. It is configured such that it can be selectively switched to a continuous mode in which the vehicle is run.

Furthermore, this tape recorder is configured so that the magnetic tape 3 can be selectively switched between normal running and reverse running at any time by a normal/reverse switching means 50, which will be described later.

In addition, in this tape recorder, when switching from normal running to reverse running in the recording mode, a recording shutoff mechanism 175 (described later) performs a shutoff operation only when there is no accidental erasure prevention claw 174 for the B side of the cassette 4. is configured to automatically enter stop mode.

Furthermore, in the recording mode, the mode switching mechanism 49 is forcibly switched to the one reciprocating mode, and the normal/reverse switching means 50 is locked in a state in which switching is disabled.

02 Next, details of the normal/reverse switching device 45 will be explained with reference to FIGS. 1 and 4 to 6C.

First, as shown in FIG. 4, the regeneration phase 16 is fixed to one end of the regeneration operation rod 53. As shown in FIG. The operating rod 53 is configured to be able to reciprocate in the arrow and h' directions at the lower part of the chassis 6, and a connecting lever 55 is connected to the other end by a pin 54. The connecting lever 55 is rotatably supported in the upper part of the chassis 6 from a shaft 561 in the directions of arrows i and i', and has a pin 57 at its free end. The connecting lever 55 is urged to rotate in the direction of arrow i' by a return spring 58 stretched between it and the chassis 6.

Next, a drive rod 60 is disposed at the bottom of the chassis 6 in the front-rear direction. The drive rod 60 has a substantially L-shape, and is configured to be able to reciprocate in the directions of arrows j and i' by guiding the rotary shaft 61 of the drive gear 38 through an elongated hole 62. And U/ formed at one end of the drive rod 60
A pin 57 of the connecting lever 55 is engaged with #63, and a tension spring 64 is stretched between the pin 57 and the drive rod 60. Further, the other end side 60a of the drive rod 60 is formed almost symmetrically on the left and right sides, and a pair of left and right regulating portions 6 made of projecting pieces are provided on both sides of a notch 65 formed on the other end side 60a.
6.67 is provided. Further, as shown in FIGS. 5 to 6C, a shaft 6 is provided at the center of the other end 60a of the drive rod 60.
8 is crimped, and a linear spring 69 having a substantially U-shape is attached to this shaft 68. And this spring 6
9 is fitted to the shaft 68 at the central portion 69c so that both ends 69a and 69b protrude toward the notch 65 side, and
It is configured to be able to swing freely in the and ' directions. A pair of drive pins 70 and 71 are provided at the other end 60a of the drive rod 60.
is fixed to the upper part of the chassis 6 so as to protrude therefrom.

Next, as shown in FIGS. 5 to 6C, a switching lever 73 is provided at the bottom of the chassis 6 and in the middle of the reel stand 7.8. This switching lever 73 is fitted into a circular hole 74 formed in the chassis 6 and is connected to the outer periphery of the NR drive gear 40 as indicated by the arrow. The NR idle gear 35 is rotatably supported on the upper surface of one end thereof.

At the other end of the switching lever 73, there is a pressed portion 75 formed of a projecting piece, and a pair of left and right restricted portions 76 on both sides of the pressed portion 75.
77 are formed laterally symmetrically. The other end of the switching lever 73 is located within the notch 65 of the drive rod 60, and the pair of restricted portions 76.77 are connected to the pair of restricted portions 66.77.
67. Therefore, both ends 69a and 69b of the spring 69 are located on both sides of the pressed portion 75 of the switching lever 73. Note that the NR idle gear 35, which is pivotally supported by the switching lever 73, and the NR drive gear 40 are always engaged.

Next, as shown in FIG. 4, a switching rod 80 is arranged between the chassis 6 and the other end 60a of the driving rod 60 so as to be substantially perpendicular to the driving rod 60. As shown in FIG. This switching rod 80 is moved between the normal position N shown by the solid line and the reverse position R shown by the dashed-dotted line by guiding the elongated hole 83.84 by the guide shaft 81.82 which also serves as the capstan 9 and the bearing of the machine 0. It is configured to be able to freely reciprocate in the directions of arrows m and m''. A spring pressing portion 85 consisting of a protrusion is provided approximately at the center of the switching rod 80, and this spring pressing portion 85 is inserted between the ends 69a and 69b of the spring 69. Further, a protrusion 86 extending toward the partially toothed gear 37 is provided at one end of the switching rod 80, and a cam hole 87 formed in this protrusion 86 is integrally formed on the upper surface of the partially toothed gear 37. Bin 89 is engaged. A pair of regulating bins 91 and 92 are fixed to the switching rod 80 so as to protrude from the upper part of the chassis 6.

Next, the operation of the normal/reverse switching device 45 configured as described above will be explained.

First, in the stop mode shown by the dashed line in FIG. 4, the connecting lever 55 is moved back in the direction of arrow i' by the return spring 58, so that the regeneration operating rod 53 is moved back in the direction of arrow h'' and is driven. The rod 60 is pressed against the bottle 57 and the arrow j
It has been moved back to the return position in the 'direction. Further, in this stop mode, the switching rod 80 is stopped at one of the normal position N shown by a solid line and the reverse position R shown by a chain line.

Here, as shown by the solid line in FIG. 6A, when the switching rod 80 is moved to the normal position iN, the spring pressing portion 85 of the switching rod 80 presses one end 69a of the spring 69 from the inside to the outside. Therefore, the spring 69 is swung in the direction indicated by the arrow as shown by the solid line, and the other end 69b presses the pressed portion 75 of the switching lever 73 from one side.
A swinging force in the direction is applied. At this time, the drive rod 60 is being moved back in the direction of the arrow j', and this drive rod 60
The pair of restricting portions 66 and 67 are simultaneously brought into contact with the pair of restricted portions 76 and 77 of the switching lever 73. Therefore, the swinging of the switching lever 73 in the direction of the arrow β is restricted, and the switching lever 73 is held in the neutral position against the spring 69.

On the other hand, when the switching rod 80 is moved to the reverse position R indicated by the dashed line, the spring pressing part 85 of the switching rod 80 presses the other end 69b of the spring 69 from the inside to the outside, so that the spring 69 is held at one point. It is swung in the direction of the arrow ' as shown by the chain line, and its one end 69a presses the pressed portion 75 of the switching lever 73 from the other side, and the switching lever 73 is given a swinging force in the direction of the arrow i'. Ru. However, the return movement of the drive rod 60 in the direction of the arrow j' restricts the swinging of the switching lever 73 in the direction of the arrow β'.
is held in a neutral position against the

Next, when the regeneration button 16 is pressed in FIG. Through this, the drive rod 60 is moved forward to the forward movement position in the direction of arrow j. Note that the regeneration operation rod 53 is in the forward movement position when its locking claw 53a is
is the lock portion 9 of the well-known lock plate 94 (see FIG. 11A).
4a and is locked, thereby driving the drive rod 60.
is also locked in the forward movement position. Note that the tension spring 64 serves as a limiter spring when the drive rod 60 is in the forward movement position.

Next, as described above, the driving rod 60 is moved forward in the direction of the arrow j by switching to the reproducing mode, and the state in which the switching rod 80 is moved to the normal position N at this time is shown in FIG. 6B. That is, the forward movement of the drive rod 60 causes the pair of restricting portions 66 and 67 to engage the pair of restricted portions 7 of the switching lever 73.
6.77 at the same time. At the same time, spring 69
Since the spring 69 is also moved forward (advanced toward the switching lever 73 side), one end 69a of the spring 69 is relatively pressed by the spring pressing portion 85 of the switching rod 80, and the spring 69 is further moved in the direction of the arrow. The switching lever 73 is rotated at the other end 69b while being swung.
The pressed portion 75 of is pressed from one side. As a result, the restriction on the swinging of the switching lever 73 is released, and the spring force of the spring 69 is further applied, and the switching lever 73 moves to the direction indicated by the arrow. The NR file gear 35 is swung in the direction of the intermediate gear 36.
is engaged with. The spring 69 exerts a limiter spring function to generate a pressure force, and the pressure force causes the NR file gear 35 to be pressure-bonded to the intermediate gear 36. Then, the rotation of the NR drive gear 40 in the direction of the arrow is transmitted to the reel base gear 30 via the NR file gear 35 and the intermediate gear 36.
The reel stand 7 is rotationally driven in the direction of arrow e and enters the normal playback mode.

When the normal running of the magnetic tape 30 reaches the end of the tape in the above-mentioned normal playback mode, the rotation of the reel stand 7 is stopped by a detector 96 such as an optical sensor disposed in the elongated hole 95 provided in the drive rod 60. Detected. Then, as shown in FIG. 4, the partially toothed gear 37 is driven half a rotation, and due to the cam action between the drive pin 89 of the partially toothed gear 37 and the cam hole 77 of the switching rod 8o, the switching rod 8o moves in the direction indicated by the arrow m'.
direction, and is moved from the normal position N to the reverse position R. When the switching rod 80 is moved to the reverse position R in the direction of arrow m' as shown in FIGS. 6B to 6C, the spring pressing portion 85 of the switching rod 80 is moved from the state in which it presses one end 69a of the spring 69. The state is changed to press the other end 69b.

As a result, the spring 69 is swung in the direction of the arrow ', and one end 69a of the spring 69 is pushed against the pressed portion 75 of the switching lever 73.
Press from the other side. At this time, drive rod 6 in playback mode.
0 has been moved forward in the direction of arrow j, so the switching lever 7
3 is not regulated, and its switching lever 73 is moved in the direction of arrow β'.
The NR file gear 35 is engaged with the reel base gear 31. Then, the spring 69 exerts a limiter spring function to generate a crimping force, and the NR file gear 35 is crimped to the reel base gear 31 by this crimping force.

Then, the rotation of the NR drive gear 40 in the direction of the arrow is transmitted to the reel base gear 31 via the NR file gear 35.
The reel stand 8 is rotationally driven in the direction of arrow g to enter the reverse playback mode.

In addition, in the above-mentioned reverse playback mode, the switching rod 80 is
When the switching lever 73 is moved from the reverse position R to the normal position N, the switching lever 73 is again swung in the direction of the arrow a as shown in FIG. 6B, and enters the normal reproduction mode. In this way, the running of the magnetic tape 3 can be selectively switched between normal running and reverse running only by reciprocating the switching rod 80.

Next, in the normal playback mode shown in Figure 6B or in the reverse playback mode shown in Figure 6C, stop! When switched to stop mode by operation of l717 or shutoff operation, the 6th A
As shown in the figure, since the drive rod 60 is moved back in the direction of the arrow j'', the switching lever 73 is held at the neutral position against the spring 69 as described above. However, at this time, the spring 69 is moved back as shown by the solid line when the switch to the stop mode is made in the normal playback mode, and as shown by the dashed line when the switch is made in the reverse playback mode. For this reason, as mentioned above, the switching lever 73 is moved by the arrow! Alternatively, it is held at the neutral position with a rocking force applied in the β' direction. Therefore, in this normal/reverse switching device 45, the normal or reverse playback mode before the stop mode is mechanically memorized by the normal position N or reverse position R of the switching rod 80 and the spring 69, and the pause mechanism and When you perform a similar pause function and then switch to playback mode,
The normal running (Figure 6B) or reverse running (Figure 6C) before the stop mode will be automatically returned.

Further, in this normal/reverse switching device 45, the spring pressing portion 85 of the switching rod 80 has one substantially U-shaped spring 69.
The other end 69b or one end 69a of the spring 69 is pressed by pressing the one end 69a or the other end 69b from the inside to the outside.
Since the switching lever 73 is pressed and swung, the switching lever 8
The spring force at the normal position N and the reverse position R of 0 is exerted under the same conditions, and the intermediate gear 36
The pressure bonding of the NR file gear 35 to the reel stand gear 31 is performed evenly.

61 Next, details of the head support mechanism 46 will be explained with reference to FIGS. 7 to 8B.

First, the magnetic head 13 and pinch rollers 11 and 12
is attached to a cassette holder 98 rotatably attached to the chassis 6. That is, this cassette holder 9
8, the head arm 100 is connected by the shaft 99 to the arrows n and n.
A magnetic head 13 is attached to this head arm 100. The tip 100a of the head arm 100 extends to the front of one of the drive pins 70 of the drive rod 60.
A protrusion 101 is provided. Also, pinch roller 1
1.12 are rotatably supported by pinch roller levers 102 and 103, and these pinch roller levers 102 and 102 are rotatably supported.
．． 103 by the axis 104.99 arrows 0 and 0', p
and p' directions so as to be swingable. Pinch roller levers 102, 103 are moved by arrows 0', p by torsion springs 105, 106 wound around shafts 104, 99.
It is biased backward in the ' direction. Further, another torsion spring 107.108 is wound around the shaft 104.99, and the tips 107a, 108a of these torsion springs 107.10B extend to the front of the pair of drive pins 70.71 of the drive rod 60. It is locked by a locking part 109, 110 formed at the tip of the pinch roller lever 102, 103. Note that the tip 107a of one torsion spring 107 is connected to the helad arm 100.
The projection 101 is abutted from the front. In addition, the switching rod 80 is located on the tip side of the pinch roller lever 102, 103.
V-shaped notches 111 and 112 are formed corresponding to the pair of regulating pins 91 and 92, respectively.

Next, the operation of the head support mechanism 46 configured as described above will be explained.

First, in the stop mode, the driving rod 60 is moved backward, so that the pair of driving pins 70 and 71 of the driving rod 60 also move toward the chassis 6.
It is moved backward within a pair of U grooves 114 and 115 formed in FIGS. 8A and 8B as shown by the dashed-dotted lines. This causes the pinch roller levers 102, 103 (return spring 105
．． At 106, the pinch rollers 11, 12 are rotated in the directions of arrows 0', p', and both the pinch rollers 11, 12 are separated from the capstan 9, 10.

At the same time, the tip 107a of the torsion spring 107 presses the protrusion 101 of the head arm 100, so that the head arm 100 is also moved back in the direction of the arrow n', and the magnetic field 13 is separated from the magnetic tape 3. There is.

Next, as shown in FIG. 8A, when the drive rod 60 is moved forward in the direction of arrow j with the switching rod 80 moved to the normal position N to switch to the normal playback mode, the pair of drive pins 70 and 71 The tip 107a of the torsion spring 107.108 is moved forward (forward) within the pair of UN1114.115,
108a is pressed. At this time, since the switching rod 80 has been moved to the normal position N, the pair of regulation bins 91.92 of the switching rod 80 are also moved within the pair of elongated holes 116, 117 provided in the chassis 6, and one The regulation bin 91 is located in front of the notch 111 of the pinch roller lever 102, and the other regulation bin 92 is removed from the notch 112 of the pinch roller lever 103. Therefore, only the pinch roller lever 102 is moved forward in the direction of arrow O, and the pinch roller 11
is crimped onto the capstan 9. The pinch roller lever 103 is regulated by the regulation bin 92, and the pinch roller lever 103 is regulated by the arrow p'.
The pinch roller 12 is maintained in a reciprocating state in the direction, and the pinch roller 12 is spaced apart from the capstan 10. One drive pin 7
0 directly presses the tip 100a of the head arm 100, the head arm lOO is moved forward in the direction of the arrow n, and the magnetic head 13 comes into contact with the magnetic tape 3.

Next, when the switching rod 80 is moved to the reverse position R as shown in FIG.
．． 117. Then, one regulation bin 91
is removed from the notch 111 of the pinch roller lever 102, restricts forward movement of the pinch roller lever 102 in the direction of arrow O, and the pinch roller 11 is separated from the capstan 9. Then, the other regulating pin 92 enters into the notch 112 of the pinch roller lever 103, and the pinch roller lever 103 is moved forward in the direction of arrow P, and the pinch roller 12 is pressed against the capstan 10.

As described above, by selectively moving the switching rod 80 between the normal position N and the reverse position R, the pinch roller 11.12 is selectively pressed against and separated from the capstan 9.10. Note that the tear springs 107 and 108 serve as limiter springs that press the pinch roller 11.12 against the capstan 9.10. At this time, when the drive rod 60 is in the forward movement state, the tips 107a and 10 of the torsion springs 107 and 108 are
8a are pressed together, the pair of regulation bottles 91.8a are pressed together.
92, the pinch roller levers 102, 103 can be
The switching of the reciprocating motion is performed smoothly.

64 Next, details of the trigger mechanism 47 will be explained with reference to FIGS. 1 and 9A to 10.

This trigger mechanism 47 applies an initial mechanical rotational force to the partially toothed gear 37 that drives the switching rod 8o between the normal position N and the reverse position R.

First, in the partially toothed gear 37, the partially toothed section 120 in the normal position and the partially toothed section 121 in the reverse position are formed so as to be offset by 180'' from each other. Nearby are a lock claw 122 in the normal position and a lock claw 1 in the reverse position, each consisting of a protrusion.
23 are integrally molded. Further, on the lower surface of the partially toothed gear 37, both lock pawls 122 and 123, a normal position pressed part 124 and a reverse position pressed part 125, each consisting of a protrusion offset by approximately 90'', are integrally molded. The pressed parts 124 and 125 have a substantially triangular shape, and slopes 124a and 125a are formed respectively.

Next, near the partially toothed gear 37 at the bottom of the chassis 6, a trigger lever 127 is pivotally supported by a shaft 128 provided on the chassis 6 so as to be swingable in the directions of arrows q and q'. A return spring 129 stretched between the two is biased to move forward in the direction of arrow q. This trigger lever 1
27, a lock arm portion 130 to which the lock claws 122 and 123 are brought into contact, an elastic arm portion 131 having elasticity for pressing the pressed portion 124 and 125, and a holding arm portion 132 are integrally made of synthetic resin. It is molded into. The lock arm part 130 and the elastic arm part 131 are connected to the lock claw 122 and the pressed part 124 in the normal position.
The partially toothed gear 3 is formed in a substantially dogleg shape so as to correspond to the lock pawl 123 and the pressed portion 125 in the reverse position.
It is inserted into the bottom side of 7. Note that the elastic arm portion 131
is curved into an arc. and holding arm portion 132
A movable iron core 134 is swingably attached to the tip of the shaft 133 by means of a shaft 133. In addition, as shown in FIG. 10, the shaft 13
3 has a barrel shape, which allows the movable iron core 134
is equipped with an automatic alignment function. Further, a tip end 135 of the holding arm portion 132 is integrally molded, and this pin 135 is inserted into a hole 136 formed in the chassis 6. At the bottom of the chassis 6, there is a movable iron core adsorption type solenoid 138 that adsorbs the movable iron core 134 and holds the trigger lever 127 in a reciprocating state in the direction of arrow q'.
is located.

Next, the operation of the trigger mechanism 47 configured as described above will be explained.

First, FIG. 9A shows the normal reproduction mode. That is, the movable iron core 134 of the holding arm portion 132 is attracted to the magnet 138a of the solenoid 138, so that the trigger lever 127 is held in a double-motion state in the direction of arrow q'. As a result, the lock pawl 122 of the partially toothed gear 37 at the normal position is engaged with the tip of the lock arm portion 130, and the partially toothed gear 37 is locked at the normal position.

Therefore, the toothless portion 120 of the toothless gear 37 at the normal position is opposed to the drive gear 38, and the magnetic tape 3 is running normally.

Then, when the normal running reaches the end of the tape and the detector 96 shown in FIG. 4 detects that the reel stand 7 has stopped rotating as described above, the solenoid 138 is momentarily energized. Then, as shown in FIG. 9B, the magnet 138a
A repulsive force of the movable iron core 134 is generated, the adsorption of the movable iron core 134 is released, and the trigger lever 127 returns to the spring 129.
It is moved forward in the direction of arrow q. By this forward movement, the engagement between the lock arm portion 130 and the lock pawl 122 is released, and the partially toothed gear 37 is unlocked. At the same time, the tip of the elastic arm 131 presses the pressed part 12 at the normal position.
The slope 124a of No. 4 is pressed, and this causes the partially toothed gear 3
7 is given a mechanical initial rotational force in the direction of arrow r,
The partially toothed gear 37 is engaged with the drive gear 38. Note that when the pin 135 of the holding arm portion 132 comes into contact with the side surface of the hole 136, the forward movement of the trigger lever 127 in the direction of arrow q is stopped.

Since the drive gear 38 is always rotationally driven in the direction of the arrow S by the rotation of the intermediate pulley 24 in the direction of the arrow S via the drive gear 41 and the intermediate gear 42, the drive gear 38 is driven as shown in FIG. 9C. The partially toothed gear 37 is indicated by the arrow r.
It is rotated in the direction. When the partially toothed gear 37 is rotated approximately 90'', the lock pawl 122 is moved along the inner circumferential surface 131a of the elastic arm portion 131, so that the elastic arm portion 131 gradually moves against the elasticity. , the trigger lever 127 is moved back in the direction of arrow q' force against the return spring 129, and the movable iron core 134 is again attracted to the magnet 138a of the solenoid 138.The movable iron core 134 is attached to the barrel-shaped shaft. 133, which has an automatic centering function and is attached to the holding arm 132.
Even if there are some molding errors of the trigger lever 127 or installation errors between the trigger lever 127 and the solenoid 138, the movable iron core 134 is reliably attracted to the solenoid 138.

Subsequently, the toothless gear 37 is rotationally driven in the direction of the arrow r, and when it has been driven half a rotation as shown in FIG. The lock pawl 123 is engaged with the tip of the lock arm portion 130, and the partially toothed gear 37 is locked in the reverse position. In addition, this time the elastic arm part 13
The pressed portion 125 in the reverse position is located near the tip of the tip.

When the toothless gear 37 is driven half a rotation as described above, the switching rod 80 is rotated by the cam action between the drive pin 89 of the toothless gear 37 and the cam hole 87 of the protrusion 86 of the switching rod 80.
is driven from the normal position N to the reverse position fR, and the normal reproduction mode is switched to the reverse reproduction mode as described above.

When the reverse travel reaches the end of the tape, the same operation as described above is performed, and the toothless gear 37 is driven half a rotation from the reverse position to the normal position, and this rotational drive moves the switching rod 80 from the reverse position R to the normal position. Driven to N.

As described above, this trigger function 47 allows the lock arm section 130 to lock and unlock the partially toothed gear 37 at the normal position and reverse position, and the elastic arm section 131
Applying mechanical initial rotational force to the partially toothed gear 37 by
The return movement of the trigger lever 127 by utilizing the rotational drive of the partially toothed gear 37 and the holding in the return movement state by the holding arm portion 132 are performed by a single trigger lever 127.

In this embodiment, the spring 69 of the normal/reverse switching device 45 is also used in addition to the trigger lever 127 to apply the mechanical initial rotational force to the partially toothed gear 37 described above. That is, as explained in FIG. 6B, when the switching rod 80 is moved to the normal position N, the spring pressing part 85 presses the one end 69a of the spring 69, so that the switching rod 80
A moving force in the direction of the reverse position R is applied by the reaction force of the spring 69. Therefore, in FIG. 9A, the drive pin 89 of the partially toothed gear 37 is pressed in the direction of arrow m' by one side 87a of the cam hole 87 of the switching rod 80. Therefore, when the partially toothed gear 37 is unlocked at the normal position, the initial rotational force from the switching rod 80 is applied to the partially toothed gear 37 . Conversely, as explained in FIG. 6C, when the switching rod 8-0 is moved to the reverse position R, the switching rod 80 is subjected to a moving force in the normal position N direction due to the reaction force of the spring 69. is working.

Therefore, in FIG. 9D, the drive pin 89 of the partially toothed gear 37
arrow m due to the other side surface 87b of the cam hole 87 of the switching rod 80.
being pushed in the direction. Therefore, when the partially toothed gear 37 is unlocked in the reverse position, the initial rotational force from the switching rod 80 is applied to the partially toothed gear 37. 05 Next, Fig. 1 and Fig. 11A - Details of the shutoff mechanism 48 will be explained with reference to FIG. 11D.

This shutoff mechanism 48 is configured to perform a shutoff operation when the magnetic tape 3 is switched from reverse running to normal running.

First, a boss portion 140 is integrally molded on the upper surface of the partially toothed gear 37, and a shutoff portion is provided on the circumferential surface of the boss portion 140 on the rear side in the rotational direction of the partially toothed gear 37 from the lock pawl 123 in the reverse position. A driving claw 141 is formed. The shut-off lever 1
43 is rotatably supported in the arrow and t' directions.

The shutoff lever 143 includes a driven pawl 144 that protrudes toward the partially toothed gear 37, and a protrusion 94b of the lock plate 94.
A drive pawl 145 that comes into contact with the protrusion 147 and a protrusion 147 having a pin 146 at its tip are integrally molded. The shutoff lever 143 is urged to rotate in the direction of the arrow by a torsion spring 148 stretched between the chassis 6 and the pin 146.

Next, the operation of the shutoff mechanism 48 configured as described above will be explained.

First, FIG. 11A shows a state in which the partially toothed gear 37 is in the normal position and locked as described above.

When the tape reaches the end of normal running, the partially toothed gear 37 is driven half a rotation in the direction of arrow r, and is locked in the reverse position as shown by the solid line in FIG. 11B. At this time, toothless gear 3
The driving claw 141 of No. 7 is located near the driven claw 144 of the shutoff lever 143. During this half-rotation drive of the partially toothed gear 37, the drive claw 141 is rotated by the shut-off lever 143.
Since it has nothing to do with this, normal driving is automatically switched to reverse driving.

Next, at the end of the tape for reverse running, gear 3 with missing teeth
7 is rotationally driven in the direction of arrow r from the reverse position,
At that moment, the drive pawl 141 of the partially toothed gear 37 kicks the driven pawl 144 of the shut-off lever 143, as shown by the dashed line, and the shut-off lever 143 torsion spring 148
is rotated in the direction of arrow t' against the As a result, the protruding piece 94b of the lock plate 94 is pressed by the drive claw 145 of the shut-off lever 143, and the lock plate 94 is moved as shown by the dashed line to engage the lock claw 53a of the regeneration operation rod 53 with the lock portion 94a. The connection is canceled. As a result, a shutoff operation is performed in which the reverse playback mode is automatically switched to the stop mode. Thereafter, the partially toothed gear 37 is driven to rotate in the direction of arrow r and is locked again at the normal position.

66 Next, details of the mode switching mechanism 49 will be explained with reference to FIG. 1 and FIGS. 11A to 11D.

First, at the bottom of the chassis 6, an L-shaped mode switching lever 151 is rotatably supported in the directions of arrows U and U' by a shaft 152 provided on the chassis 6. A return spring 153 stretched between the two is biased to rotate in the direction of arrow U'. One end 151a of this mode switching lever 151 is connected to the shutoff lever 1.
43 side, and a pin 146 of the shut-off lever 143 is brought into contact with one end 151a thereof.

Therefore, rotation of the shutoff lever 143 in the direction of the arrow is restricted by the mode switching lever 151.

Note that there is a notch 154 on the other end side of the mode switching lever 151.
is formed. Further, at the bottom of the chassis 6, an operating lever 15 is provided which is substantially orthogonal to the other end of the mode switching lever 151.
6 is pivotally supported by a shaft 157 provided on the chassis 6 so as to be rotatable in the force directions of arrows V and v'. Note that a pin 158 is integrally molded on the operation lever 156, and this pin 155 is engaged with a notch 154 of the mode switching lever 151.

Next, the operation of the mode switching mechanism 49 configured as described above will be explained.

First, FIG. 11B shows a state in which the operating lever 156 is switched in the direction of arrow V, and the mode switching mechanism 49 is switched to one reciprocating mode. That is, since the pin 158 of the operating lever 156 enters the notch 154 of the mode switching lever 151, the mode switching lever 151 is rotated in the direction of arrow U' by the return spring 153. Therefore,
The pin 146 of the shutoff lever 143 is brought into contact with one end 151a of the mode switching lever 151, and the shutoff lever 143 is held in a solid line state. As a result, the shutoff lever 143 is switched to the operating state, and as described above, the shutoff operation is performed at the moment the partially toothed gear 37 is rotationally driven from the reverse position to the normal position.

That is, in this single reciprocating mode, the magnetic tape 30 is automatically stopped after normal running and then reverse running.

Next, as shown in FIG. 11C, when the operating lever 156 is switched in the direction of arrow W', the pin 1 of the operating lever 156
58 is pulled out from within the notch 154 of the mode switching lever 151, so that the mode switching lever 151 is rotated in the direction of arrow U against the return spring 153. Then, by moving one end 151a of the mode switching lever 151, the shutoff lever 143 is rotated in the direction of the arrow by the torsion spring 148, and the driven pawl 144 follows the rotation locus of the driving pawl 141 of the partially toothed gear 37. Separated from within. As a result, the shutoff lever 143 is switched to a non-operating state, and even when the partially toothed gear 37 is rotationally driven from the reverse position to the normal position, the driving pawl 141 passes through the driven pawl 144 without kicking it.

That is, in this continuous mode, the magnetic tape 3 is repeatedly and continuously run in normal running and reverse running.

07 Next, details of the normal/reverse switching means 50 will be explained with reference to FIG. 1 and FIGS. 11A to 11D.

First, a switching operation lever 161 is arranged at the bottom of the chassis 6. This switching operation rod 161 is configured to be able to reciprocate in the directions of arrows W and W' by having its elongated hole 162 guided by a guide pin 163 provided on the chassis 6. The switching operation rod 161 includes an elastic arm 164 having elasticity, a pin 165, and a protrusion 166 that are integrally molded from synthetic resin. and elastic arm 164
The switching lever 161 is moved back in the direction of the arrow W' by elastically abutting the tip of the switching lever 161 against the stepped portion 168 of the chassis 6. Further, a changeover switch 169 made of a leaf switch is arranged near the pin 165. Further, the protrusion 166 is located at the other end 151b of the mode switching lever 151.
is in contact with.

Next, the operation of the normal/reverse switching means 50 configured as described above will be explained.

First, as shown by the dashed line in Fig.
61 in the direction of arrow W, the changeover switch 169 is actuated by the pin 165 of the changeover operation lever 161. Then, the solenoid 138 is momentarily energized, and the trigger mechanism 47 is activated as described above, causing the partially toothed gear 370 to be activated.
Rotation drive is started.

At this time, as explained in FIG. 11C, the mode switching mechanism 4
9 is switched to continuous mode, the shutoff operation is not performed when switching from reverse to normal driving, so pressing the switching operation lever 161 allows you to selectively switch between normal driving and reverse driving at any time. Can be switched. However, as explained in FIG. 11B, if the mode switching mechanism 49 is switched to the single reciprocating mode, the shutoff operation is performed when switching from reverse driving to normal driving, so the switching operation lever 161 is not operated during reverse driving. If you press it, it will be shut off.

However, according to this normal/reverse switching means 50, there is only one point tm&! in FIG. 11D. As shown in , when the switching operation rod 161 is pushed in the direction of arrow W while the mode switching mechanism 49 is switched to the single reciprocating mode, the protrusion 166 of the switching operation rod 161 causes the mode switching lever 151 to The other end 151b is pressed, and the mode switching lever 151 is forcibly rotated in the direction of arrow U against the return spring 153 as shown by a chain line. That is, when the switching operation lever 161 is pressed, the mode switching mechanism 49 is forcibly switched to the continuous mode explained in FIG. 11C, and the shutoff operation is not performed when switching from reverse running to normal running. , it becomes possible to selectively switch between normal driving and reverse driving at any time.

Note that the shutoff lever 143 is switched to the non-operating state by forced rotation of the mode switching lever 151 only while the switching operation rod 161 is pressed; however, when the switching operation rod 161 is pressed, Since the partially toothed gear 37 is immediately driven to rotate, by the time the mode switching lever 151 is moved back after releasing the switching operation rod 161, the shutoff operation has already been performed and the mode has been switched to normal running.

Gl Next, details of the recording switching mechanism 172 will be explained with reference to FIGS. 1 and 12 to 13C.

First, the recording button 15 is fixed to one end of a recording operation lever 180 disposed at the lower part of the chassis 6 on the side of the playback operation lever 53. The recording operation rod 180 is connected to a guide bin 181.182 provided in the chassis 6 through a long hole 183.18.
4 to be able to reciprocate in the directions of arrows A and A', and a return spring 185 stretched between the guide pin 163 for the switching operation rod 161
It is biased backward in the ' direction. And recording operation rod 180
A protrusion 186 is formed therein, and this protrusion 186 is engaged with a notch 53b provided in the regeneration operation rod 53. Further, a lock pin 187 having a substantially triangular prism shape is implanted on the upper surface of the recording operation rod 180 near the protrusion 186 .

Next, at the bottom of the chassis 6, there are two accidental erasure prevention claws 17 for side A and side B provided on the cassette 4 to be installed.
Two detection rods 190 and 191 for side A and side B, which independently detect the presence or absence of 3.174, are arranged substantially perpendicular to the reproduction and recording operation rods 53 and 180. The detection rod 190 for side A is configured to be able to reciprocate in the directions of arrows B and B' by having guide pins 192 and 193 provided on the chassis 6 guide elongated holes 194 and 195. The rod 191 is superimposed on the lower part of the A-side detection rod 190 and is configured to be able to reciprocate in the force directions of arrows C and C' by having a guide pin 193 guide an elongated hole 196. Both detection rods 190 and 191 are biased toward each other in the direction of force indicated by arrows B' and C' by a tension spring 197 stretched between them. And both detection rods 190
．． A shaft 19 provided on the chassis 6 is attached to one end side of the 191.
Detection lever 20 rotatably supported by 8.199
0.201 are connected in bins 202 and 203, respectively. Note that the detection levers 200 and 201 have detection pieces 200a and 201a that protrude from the top of the chassis 6. Further, elongated holes 204 and 205 are formed in the overlapping portions of both detection rods 190 and 191. Furthermore, a lock portion 206 made of a protruding piece is formed at the other end of the detection rod 190 for the A side, and a hole 207 is formed at one end of the detection rod 191 for the B side.
A lock portion 208 made of a protruding piece is formed at the portion.

Then, the locked bin 187 of the recording operation rod 180 is inserted into the hole 207 from below, and the two locking parts 206.2
It is located between 08.

Next, a control lever 210 is pivotally supported at the lower part of the chassis 6 by a shaft 56 of the connecting lever 55 so as to be able to swing in the directions of arrows and D'. 211 are inserted into the elongated holes 204, 205 of both detection rods 190, 191. A bent portion 210a is formed at the other end of the control lever 210, and this is engaged with a notch 212 formed at the tip of the protrusion 86 of the switching rod 80, as shown in FIG. 14A. There is.

Next, the operation of the recording switching mechanism 172 configured as described above will be explained.

First, FIG. 13A shows a state in which the switching rod 80 is moved to the normal position N. That is, the control lever 210 is driven by the movement of the switching rod 80 to the normal position N.
is swung in the direction of the arrow.

Then, the bottle 211 of the control lever 210 presses one end edge 205a of the long hole 205 of the detection rod 191 for the B side.
The detection rod 191 is moved forward in the direction of arrow C against the tension spring 197 and is regulated to the unlocked position. As a result, the lock portion 208 of the detection rod 191 is disengaged from the locked pin 187 of the recording operation rod 180. On the other hand, since the detection rod 190 for side A is not restricted by the pin 211 of the control lever 210, it can reciprocate between the unlocked position moved forward in the direction of arrow B and the locked position moved back in the direction of arrow B'. controlled to a possible state.

Therefore, when the switching rod 80 is in the normal position N, the detection rod 190 for the A side is attached to the claw 1 for the A side of the cassette 4.
73 will be detected independently.

As shown in FIG. 13A, in the absence of the A-side pawl 173, the detection piece 200a of the detection lever 200 is not regulated, so the detection rod 190 is moved back to the lock position in the direction of arrow B' by the tension spring 197. Ru. As a result, the lock portion 206 of the detection rod 190 is engaged with the locked pin 187 of the recording operation rod 180, and the recording operation rod 180 is locked at the backward movement position in the direction of arrow A'. Therefore, it is not possible to press the record button 15 and it is not possible to switch to the record mode.

On the other hand, when the claw 173 for side A of the cassette 4 is present as shown in FIG. 13C, the detection piece 20 of the detection lever 200
0a is restricted by the claw 173, the detection lever 200 is rotated and the detection rod 190 is moved forward to the unlocked position in the direction of arrow B against the tension spring 197. As a result, the lock portion 206 of the detection rod 190 is disengaged from the locked pin 187 of the recording operation rod 180, and the recording operation rod 180 is unlocked at the return position. Therefore, record button 15
By pressing , the recording operation rod 180 is moved forward in the direction of arrow A, making it possible to switch to the recording mode.

Next, FIG. 13B shows a state in which the switching rod 80 has been moved to the reverse position R. That is, this time the control lever 210
is swung in the direction of arrow D', this control lever 21
The elongated hole 20 of the detection rod 190 for the A side is connected by the pin 211 of 0.
4 is pressed, and the detection rod 190 is regulated to the unlocked position where it is moved forward in the direction of arrow B against the tension spring 197. On the other hand, since the detection rod 191 for the B side is not restricted by the pin 211 of the control lever 210, it can reciprocate between the unlock position moved forward in the direction of arrow C and the lock position moved back in the force direction of arrow C'. controlled to a possible state.

Therefore, when the switching rod 80 is in the reverse position R, the B-side detection rod 191 independently detects the B-side pawl 174 of the cassette 4. In the absence of the claw 174 for surface B, the detection rod 191 is moved back to the lock position in the force direction of arrow C' by the tension spring 197. As a result, the lock portion 208 of the detection rod 191 is engaged with the locked pin 187 of the recording operation rod 180, and the recording operation rod 180 is locked at the backward movement position in the direction of arrow A'.

On the other hand, as shown in FIG. 13C, when the claw 174 for surface B is present, the detection lever 201 is rotated and the detection rod 191
is moved toward the unlocked position in the direction of arrow C against the tension spring 197. As a result, the lock portion 2 of the detection rod 191
08 is removed from the locked pin 187 of the recording operation rod 180, and the recording operation rod 180 is unlocked at the return position.

Therefore, by pressing the record button 15, the record operation lever 18
0 is moved forward in the direction indicated by the arrow, allowing switching to the recording mode.

As mentioned above, even if the claws 173 and 174 for the A side or B side of the installed cassette 4 are missing and recording cannot be performed in normal driving or reverse driving, the cassette 4 can be reinstalled (with the AB side By selectively moving the switching rod 80 to the reverse position iR or the normal position N without turning it over, the claw 174 for the B side or the A side can be moved in that state.
．． 173 allows recording in reverse or normal driving. The switching rod 80 can be moved by operating the normal/reverse switching means 50 described in section 07 above.

G. Next, Figures 1, 12, 14A to 14F
Details of the recording shutoff mechanism 175 will be explained with reference to the drawings.

First, the shut-off switching rod 214 of the recording shut-off mechanism 175 is arranged to overlap the lower part of the recording operation rod 180, and the guide pins 215 and 216 implanted in the recording operation rod 180 and the R'i guide By letting the pin 181 guide the elongated holes 217, 218, and 219,
It is configured to be able to freely reciprocate in the directions of arrows E and E'. A shut-off lever 220 is rotatably supported at the tip of the shut-off switching rod 214 by a shaft 221 in the directions of arrows F and F', and is biased to rotate in the direction of arrow F by a torsion spring 222. There is. A pin 223 is formed on the shut-off lever 220, and this pin 223 abuts against a protrusion 224 formed on the recording operation rod 180. Further, a U groove 225 is formed at the other end of the shutoff switching rod 214, and a pin 226 implanted in the detection lever 201 of the detection rod 191 for the B side is inserted into the long hole of the recording operation rod 180 in this U groove 225. 227 is inserted and engaged. Therefore, this shut-off switching rod 214 is reciprocated in the directions of arrows E and E' by the rotation of the detection lever 201, that is, by the reciprocating movement of the detection rod 191 depending on the presence or absence of the accidental erasure prevention claw 174 for side B of the cassette 4. It is configured to

Next, the operation of the recording shutoff mechanism 175 configured as described above will be explained.

First, in FIG. 14A, the switching rod 80 is in the normal position N in the stop mode, and the attached cassette 4 has a claw 1 for side A.
73, and there is no claw 174 for the B side. Since the switching rod 80 is in the normal position N, the control lever 210 is swung in the direction of the arrow, and the detection rod 190 for the A side is controlled to be able to reciprocate, but since there is a pawl 173 for the A side, The detection rod 190 is moved forward in the direction of arrow B to the unlocked position, making it possible to switch to the recording mode.

Here, if you press the record button 15 as shown in FIG. 14B,
The recording operation rod 180 is moved forward to the forward position in the direction of arrow A, and the stop mode is switched to the recording mode. At this time, the protrusion 186 of the recording operation rod 180 pushes the notch 53b of the playback operation rod 53, so the playback operation rod 53 is also moved forward in the direction of the arrow, and its lock claw 53a locks into the lock portion 9 of the lock plate 94.
4a and is locked. In addition, the recording operation rod 180
The locking claw 180a is connected to the locking portion 94 of the locking plate 94.
c and is locked in the forward movement position.

Therefore, the mode becomes the normal recording mode, similar to the normal playback mode explained in Section 62 above.

Next, when the normal running of the magnetic tape 3 reaches the tape end in the normal recording mode, as shown in FIG. 14C,
The partially toothed gear 37 is rotated in the direction of arrow r, and the switching rod 80 is rotated.
movement from the normal position N to the reverse position R is started. At this time, the control lever 210 is swung in the direction of arrow D', and the B-side detection rod 191 is now controlled to be reciprocally movable. Then, since there is no claw 174 for the B side, the detection piece 201a of the detection lever 201 is not regulated, and the detection rod 19
1, the detection lever 201 is rotated by the backward movement in the direction of arrow C'. Due to this rotation of the detection lever 201, the shutoff switching rod 214 is moved back in the direction of arrow E', and the driven pawl 228 at the tip of the shutoff lever 220 is connected to the partially toothed gear 3.
It is inserted into the rotation locus of the drive claw 229 formed at 7. That is, the recording shutoff mechanism 175 is switched to the operating state. As shown in FIG. 14D, the drive claw 229 is rotated by the partially toothed gear 37 in the direction of the arrow r.
kicks the driven pawl 228 of the shutoff lever 220,
The shutoff lever 220 is rotated in the direction of arrow E' against the torsion spring 222. The pin 223 of this shut-off lever 220 is connected to the protrusion 94d of the lock plate 94.
By pressing , the lock plate 94 is moved and the recording operation lever 180 is unlocked, and the playback operation lever 53 is also unlocked to enter the stop mode.

In this way, if the B-side pawl 174 is not present when switching from normal running to reverse running, a shutoff operation is automatically performed at the time of the switching.

On the other hand, as shown in FIG. 14E, when there is a pawl 174 for the B side, even if the detection rod 191 for the B side can freely reciprocate when switching from normal driving to reverse driving, the detection lever 201 can Since the piece 201a is restricted by the claw 174 and the detection lever 201 is not rotated, the shutoff switching rod 214 is held in a forward movement state in the direction of arrow E. That is, the driven pawl 228 of the shutoff lever 220 is removed from the rotation locus of the drive pawl 2290 of the toothless gear 37, and the recording shutoff mechanism 175 is switched to a non-operating state. Therefore, the partially toothed gear 37 is
Even if the driving claw 229 is rotationally driven in the direction, the driving claw 229
8 is passed without kicking, and the shutoff operation is not performed.

That is, normal running is switched to reverse running while the recording mode is maintained, and reverse recording is performed following normal recording.

After that, when the tape reaches the end during reverse running in the reverse recording mode, the shutoff lever 143 of the shutoff mechanism 48 is driven as shown in FIG. automatically switches from reverse recording mode to stop mode. That is, for shutoff after reverse recording, the shutoff mechanism 48 after reverse playback is shared.

As shown in FIG. 14A, when the recording operation lever 180 is moved back to the backward movement position in the direction of arrow A', the shutoff lever 220 of the recording shutoff mechanism 175 is moved so that the bin 223 is moved back to the recording operation lever. 180(7) Since it is not pressed by the protrusion 224, it is rotated in the direction of arrow F by the torsion spring 222.

Therefore, even if the reproduction mode is in the continuous mode described in item 06 above, the shutoff lever 220 is not driven by the drive claw 141. and the first
As shown in FIG. 4B, when the recording mode is switched, the bottle 223 of the shut-off lever 220 is pressed by the protrusion 224 of the recording operation rod 180 and rotated in the direction of arrow F', and further as shown in FIG. 14C. Thus, when there is no pawl 174 for the B side, it will be inserted into the rotation locus of the drive pawl 229.

As described above, in the recording mode, when switching from normal running to reverse running, the claw 174 for the B side of the cassette 4
Only when there is no pawl 174 for the B side, it is automatically shut off at the time of switching, and when there is a pawl 174 for the B side, it is automatically switched to reverse travel.

G. Next, the mode switching mechanism 49 in the recording mode will be explained with reference to FIGS. 1 and 14A to 14F.

First, a pin 233 is integrally molded at the tip of the operation lever 156 of the mode switching mechanism 49, and the recording operation lever 180
A pressing portion 232 consisting of a protrusion that presses the pin 233 is provided. That is, the operating lever 156 is arranged substantially perpendicular to the recording operating rod 180, and the operating lever 156
The tip of the recording operation rod 180 is inserted into the movement locus of the pressing portion 232 of the recording operation rod 180.

According to such a mode switching mechanism 49, when the recording operation rod 180 is in the backward movement position as shown in FIG. 14A,
Since the bottle 233 of the operating lever 156 is not pressed by the pressing portion 232 of the recording operating rod 180, the reproducing mode can be switched between the one reciprocating mode and the continuous mode by switching the operating lever 156 as explained in item 06 above. . However, when the mode is switched to the recording mode as shown in FIG. 14B, the pin 233 of the bar 156 is pressed by the pressing portion 232 of the recording operation lever 180, and the operation lever 156 is forcibly rotated in the direction of arrow V. be moved. Therefore, even if the mode switching mechanism 49 is switched to the continuous mode when switching to the recording mode, the recording mode in which the recording operation rod 180 is moved forward is forcibly set to the one-reciprocation mode. In other words, it is always shut off after recording in reverse driving,
There is no possibility of switching from reverse driving to normal driving again.

01 Next, according to FIG. 1 and FIGS. 14A to 14F,
The normal/reverse switching means 50 in the recording mode will be explained.

First, the switching operation lever 1 of the normal/reverse switching means 5o
61 is integrally molded with a protrusion 237, and the recording operation rod 180 has a regulating portion 2 formed of a protrusion that comes into contact with the protrusion 237.
36 are provided. That is, the switching operation rod 161 is disposed substantially perpendicular to the recording operation rod 180, and the regulating portion 236 of the recording operation rod 180 is aligned with the protrusion 237 of the switching operation rod 161.
It is configured to be inserted within the movement trajectory of.

According to such normal/reverse switching means 50,
As shown in FIG. 14A, when the recording operation rod 180 is in the backward movement position, the protrusion 237 of the switching operation rod 161 is not restricted by the restriction section 236 of the recording operation rod 180, so that the 09
As explained in section 14, by moving the switching operation rod 161 in the direction of arrow W, it is possible to selectively switch between normal running and reverse running at any time in playback mode.However, as shown in Fig. 14B, in recording mode When the recording operation lever 180 is switched to
It is inserted into the movement locus of the protrusion 237 of 61. That is, the switching operation rod 161 is locked in a state in which it is moved back in the force direction of arrow W', which is a state in which switching is impossible. Therefore, in the recording mode, selective switching between normal driving and reverse driving becomes impossible.

G, □ Next, details of the erasing head drive mechanism 176 will be explained with reference to FIGS. 1 and 15 to 16B.

First, the erasing heads 177 and 178 for normal running and reverse running are connected to the erasing lever 240, respectively.
, 241, and these erase head levers 240, 241 are rotatably attached to the helad arm 100 by a shaft 242. These erasing levers 240 and 241 are urged to rotate in a direction away from the magnetic tape 3 by a torsion spring 243. Also, the erase levers 240 and 241 have pins 244 and 245.
is integrally molded.

On the other hand, on the side of the switching rod 80, a drive lever 246 is movable reciprocally in the directions of arrows G and G' by guiding a long hole 248 to a guide bin 247 provided in the chassis 6. It is configured to be rotatable in the direction.

The drive lever 246 is moved forward in the direction of arrow G by a tension spring 249 stretched between it and the drive rod 60.

Further, a protrusion 250 is formed on the end portion 246a (!Ij) of the drive lever 246, and the protrusion 250 is configured to abut against a protrusion 251 formed on the switching rod 80.

A pair of L-shaped pressing portions 252 and 253 are formed at the other end of the drive lever 246 extending below the erasing head 177 and 178.
A recess 254 is formed on the side. Furthermore, the drive lever 24
6 is pressed by the end 180b of the recording operation rod 180.

Next, the erasing head drive mechanism 17 configured as described above is
The operation of step 6 will be explained.

First, when the recording operation rod 180 is moved forward in the direction of arrow A to switch to the recording mode, as shown from the dashed line to the solid line in FIG. 246a is pressed, and the drive lever 246 is rotated in the direction of arrow H. When the switching rod 80 is moved to the normal position N, the drive lever 246 is moved forward in the direction of arrow G (in the embodiment, it is moved forward by the tension spring 249), so one of the drive levers 246 The pressing part 252 is inserted into the pin 244 of the rad lever 240 for normal driving, and the other pressing part 253 is inserted into the pin 244 of the rad lever 241 for reverse driving, and the pin 245 is positioned in the concave part 254. do. Therefore, when the drive lever 246 is rotated in the direction of the arrow H, the pin 244 is pressed by one of the pressing parts 252, and only one of the erasing head levers 240 is pressed against the torsion spring 2.
Rad 177 is rotated in the direction of the arrow ■ against 43 and erased.
only the magnetic tape 3 is contacted.

On the other hand, when the switching rod 80 is moved to the reverse position R as shown in FIG. 16B, the protrusion 251 of the switching rod 80
The protrusion 250 of the drive lever 246 is pressed, and the drive lever 246 is moved back in the direction of arrow G' against the tension spring 249. Then, one pressing portion 252 of the drive lever 246 comes off the pin 244, and the other pressing portion 252
53 is located in the bin 245 portion. Therefore, when the drive lever 246 is rotated in the direction of arrow H, the other pressing portion 25
3 presses the pin 245, and only the other erasing head lever 241 is rotated in the direction of arrow I' against the torsion spring 243, so that only the erasing head 178 comes into contact with the magnetic tape 3.

Note that when switching from normal driving to reverse driving in recording mode, the drive lever 24 is moved by moving the switching rod 80.
6 is moved back in the direction of arrow G' while being rotated in the direction of arrow H. However, at the same time as the erasing head 177 for normal running is separated from the magnetic tape 3, the erasing head 178 for reverse running is magnetically moved. The tape 3 is contacted. Like this 1
Since the two erasing heads 177 and 178 are selectively driven by the two drive levers 246 in accordance with normal running and reverse running, the two erasing heads 177 and 178 are selectively driven when switching between normal running and reverse running. is driven continuously and smoothly.

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, a structure for switching to recording mode using a recording operation lever, a structure for switching between normal running and reverse running using a switching lever,
The detection structure of the erroneous erasure prevention claw using the detection rod and the structure of the shutoff mechanism are not limited to the structure of the embodiment, and various structures can be applied.

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

H Effects of the Invention As described above, according to the present invention, when switching from normal running to reverse running, the B
When there is a claw for the surface, it can automatically switch to reverse running, and when there is no claw, it can be automatically shut off. Therefore, if the claw for the B side is removed, it will be shut off reliably after recording in normal driving, and accidental double recording in reverse driving can be prevented, making recording extremely safe.

[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 cassette, in which FIG. 1 is an overall plan view, FIG. 2 is an exploded perspective view of a tape running drive system, and FIG. Fig. 3 is a plan view of the same as above, Fig. 4 is a plan view of the normal and reverse switching device, Fig. 5 is an exploded perspective view of the main parts of the same, Figs. 7 is a perspective view of the head support mechanism, FIGS. 8A and 8B are plan views of the same, FIGS. 9A to 9D are plan views of the trigger mechanism, FIG. 10 is a sectional view of the same, and FIGS. 11A to 11A.
Fig. 11D is a plan view of the shutoff mechanism, mode switching mechanism, and normal/reverse switching means; Fig. 12 is an exploded perspective view of the recording switching mechanism and recording shutoff mechanism;
Figures 3A to 13C are plan views of the recording switching mechanism, and Figure 14A is a plan view of the recording switching mechanism.
Figures 14F to 14F are plan views of the recording shutoff mechanism, mode switching mechanism, and normal/reverse switching means;
The figure is an exploded perspective view of the erasing head drive mechanism, and FIGS. 16A and 16B are plan views of the same. In addition, in the symbols used in the drawings, 3--1--...--m=...Magnetic tape 4--
−−−−−−−−・−−−−11−Cassette 7・−−11−−−−−・−・−・−・−Reel stand 8−−−
1・・・・・−・−Reel stand 15−・−・・−−1−−
−−〜−・−・Record button 37・−・・−・−・−・−・−
Missing tooth gear 45・-11--------・-1--------
Normal/reverse switching device 80...--1------
・・−・−・−Switching rod 173・・−・−・・・・−−−
- Accidental erasure prevention claw 174・−・−・・−・−・−−−−
1. Erroneous erasure prevention claw 175 - 1. Recording shutoff mechanism 180 . . . 11 -
---・Recording operation rod 190-----・-・-
Detection rod 191---------・----111 detection rod 2
01・---------・---m-detection lever 210
−・−−−−−−−−−−・−Control lever 214−−
−−−−−−−−−−・Shutoff switching rod 220−
・−・・−−−1−−−−Shutoff lever 228
・−・・−−１−−・・・−・−Driven claw 229−−−
-------------One driving claw.

Claims (1)

[Claims] A reciprocating recording operation rod that switches from a stop mode to a recording mode by being moved forward from a backward movement position to a forward movement position, and a recording operation rod that can be moved between a normal position and a reverse position to normalize tape running. They are independent of each other due to the presence or absence of a switching rod that selectively switches between running and reverse running, and two accidental erasure prevention claws for the A side and B side provided on the tape cassette that is controlled by this switching rod and installed. two detection rods for the A side and the B side that are reciprocated by the
The shutoff mechanism is switched between a non-operating state and an operating state by the reciprocating movement of a surface detection rod, and in the operating state performs a shutoff operation when switching from normal driving to reverse driving, and the above-mentioned recording operation When switching from normal running to reverse running in the recording mode in which the rod has been moved forward to the forward position, the switching rod is moved to the reverse position, so that the B side detection rod detects the B side of the tape cassette. detects the presence or absence of the claw, and when the claw is present, the shutoff mechanism is not operated, and only when the claw is absent, the shutoff mechanism is switched to the operating state by the detection rod for side B, and the shutoff operation is performed. An auto-reverse recording and reproducing device configured to perform.