JPS5815849B2 - Shut-off mechanism in recording/playback equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shutoff mechanism in a recording and reproducing apparatus suitable for application to, for example, a tape recorder, and particularly.

(a) A detection member which is rotationally biased in a predetermined direction by the rotation of the reel shaft, and whose bias is released when the rotation of the reel shaft is stopped, and which has a first recess and a second recess. (b) A drive member that is constantly driven by a motor.

(c) It is reciprocated by the driving member, and when the reel shaft is rotating, it reciprocates within the first recess with a first stroke, and when the reel shaft is stopped, it reciprocates within the second recess. a reciprocating member having a pin that reciprocates with the second stroke; (d) a lock that operates when the reciprocating member reciprocates with the second stroke to release a lock plate of a play button or a record button; Plate operating member.

The present invention relates to a shut-off mechanism in a recording/playback apparatus that unlocks a playback button or a record button when the rotation of the reel shaft stops due to the tape end during playback or recording.

In this type of conventional device, the rotational bias of the detection member is released in the stopped state and the detection member is in a state where it can freely rotate. Often, it is stopped while being rotated in the opposite direction.

When the stopped state is switched to the playback state or the recording state, the moment the playback button or the record button is pressed, the pin of the reciprocating member driven by the drive member moves to the detection member. The lock plate actuating member is unexpectedly moved into the second recess and reciprocated in the second stroke, and the lock plate actuating member is unexpectedly released and the shut-off operation is unexpectedly performed.

That is, there was a major defect in that a shutoff malfunction occurred the moment the playback button or record button was pressed.

The present invention aims to provide a device that can prevent such shutoff malfunctions.

An embodiment in which the present invention is applied to a cassette tape recorder will be described below with reference to the drawings.

This tape recorder 1 uses an ordinary compact cassette 2, and yet the cabinet 3 is constructed to be extremely thin and exhibits an extremely compact outer diameter as a whole.

FIG. 1 shows the entire tape recorder 1, which has the above-mentioned characteristics.

The right rear corner of cabinet 3 has three
A cassette mounting section 6 with an open surface is formed, and a compact cassette (hereinafter simply referred to as "set") 2 is mounted onto the cassette device section 6 from above in the same manner as in the prior art.

The upper surface, right side surface, and rear surface of the cassette mounting portion 6 are configured to be opened by an opening/closing lid T pivotally mounted to the cabinet 3.

Further, on the front end side of the cabinet 3 and at a position on the right side, five push buttons are arranged in order from the left: a rewind button 8 that also serves as a review, a stop button 9, a play button 10, a fast forward button 11 that also serves as a cue, and a record button 12. There is.

Further, an eject button 13 is provided on the left side of the cassette mounting section 6 of the cabinet 3.

Figures 2 to 4 show the characteristic mechanical board 15 and head board 1.
This shows the relationship with 6.

The mechanical board 15 is manufactured by sheet metal processing as is conventionally known, and is housed within the cabinet 3.

In the cassette mounting section 6, this mechanical board 15 has a main flat plate part 15a on the rear side and a main flat plate part 15a on the front side.
It is formed in a low flat plate part 15b that is recessed downward with respect to 5a, and these parts are connected by a one-step difference part 15c.

A pair of left and right reel shafts 17 and 18 for feeding and winding, a cassette presser spring 21, etc., which are conventionally known, are connected to the mechanical board 1.
It is attached to the main flat plate part 15a of the capstan 6.
0 and a pair of left and right cassette positioning pins 20at20b
etc. are attached to the low flat plate portion 15b of the mechanical board 15 at a position offset toward the rear side.

On the other hand, the head substrate 16 has a conventionally known T-shape, and is composed of a front plate portion j6a extending in the left-right direction and a rear plate portion 16b extending rearward from the front plate portion j6a.

However, the head substrate 16 is provided with a stepped portion 16c at the connection portion between the front plate portion 16a and the rear plate portion 16b.
The rear plate portion 16b is configured lower than the front plate portion 16a.

The rear plate portion 16b is inserted into a long hole-shaped notch 22 cut out from the low flat plate portion 15b to the stepped portion 15c of the mechanical board 15, and extends to a position below the main flat plate portion 15a. .

Further, at this time, the front end side of the rear plate portion 16b is configured to be flush with the low flat plate portion 15b.

Note that, as is conventionally known, on the upper surface of the front plate portion 16a of the head substrate 16, an erasing head 23, a recording/reproducing head 24,
A pinch roller 25 is attached.

However, the erasing head 23 and the pinch roller 25 are moved to the fulcrum pins 28 and 25 by levers 26 and 27, respectively, as in the conventional case.
29, and is rotatably attached via a tension spring 30.
．． 31, each is biased to rotate clockwise in FIG.

In addition, 32 in the figure is a decorative board formed from a thin plate, and this decorative board 32 also has main flat plate portions 32 corresponding to the main flat plate portion 15a, the low flat plate portion 15b, and the stepped portion 15c of the mechanical board 15, respectively.
a, a low flat plate portion 32b, and a step portion 32c are formed.

The decorative board 32 is overlapped and bonded to the upper surface of the mechanical board 15 so as to be in close contact therewith.

However, by providing the mechanical board 15 with the downwardly recessed flat plate part 15b as described above, and configuring this low flat plate part 15b to be flush with the rear plate part 16b of the head board 16, The cassette 2 can be mounted extremely close to the head substrate 15, thereby making it possible to make the cabinet 3 extremely thin.

That is, the cassette 2 has a cassette housing 2 as is conventionally known.
A pair of upper and lower bulges 2 b and 2 c are provided on the upper and lower surfaces of the front end of a.
is formed.

However, when this cassette 2 is installed, the lower bulge 2
As clearly shown in FIG. 3, it is possible to enter the concave space 33 on the low flat plate part 15b which is recessed downward with respect to the main flat plate part 15a of the mechanical board 15.

However, this lever allows the cassette 2 to be mounted extremely close to the main flat plate portion 15a of the head substrate 15, which greatly contributes to making the entire cabinet 3 extremely thin.

5 to 25 show a characteristic mode switching mechanism.

First, the push button device will be explained, which is clearly shown in FIG. 10 and FIGS. 18 to 25.

That is, the five push buttons 8 to 12 are each rotatably supported by a common fulcrum shaft 40 installed on the mechanical board 15.

Each of these push buttons 8 to 12 is made of synthetic resin and has an inverted cross-section.
．． The vertical pieces 10, 11 and 12 are lever pressing parts 8a and 12, respectively.
10a.

11a and 12a, and the vertical piece of the stop button 9 is configured as an operating portion 9a of a lock plate, which will be described later.

Of these push buttons, the stop button 9, play button 10, and record button 12 are moved back by a leaf spring 41, but the rewind button 8 and fast forward button 11 are configured to be moved back by a lever to be described later. has been done.

On the other hand, the lock plate 43 for locking the other push buttons 8, 10.
This lock plate 43 is also formed into an ultra-thin shape.

However, in this case, the lock plate 43 has a reinforcing plate (metal plate) 14 having a KL-shaped cross section closely attached to the lower surface, and a plurality of welded dowels 45 integrally formed on the lock plate 43 are attached to the reinforcing plate 44. These dowels 43 and 44 are inserted into a plurality of dowel holes 46, and are integrally joined and reinforced by welding of these welding dowels 45.

This lock plate 43 is rotatably supported at both ends by a pair of fulcrums 1° 4T on the mechanical board 15,
It is urged to rotate counterclockwise in FIGS. 19 to 23 by a reciprocating tension spring 48.

On the upper surface of the rear edge side of this lock plate 43, there are claws 54, 55, 56, 57 corresponding to the push buttons 8 to 12, respectively.
.

58 are integrally molded.

At this time, the claws 54 corresponding to the rewind button 8 and the fast forward button 11.
57 is a claw 55 formed into a small mountain and corresponding to the stop button 9.
is formed into the largest mountain, play button 10 and record button 12
The corresponding pawls 56, 58 are formed into medium-sized peaks.

Note that other than the stop button 9 and play button 10, other push buttons 8, 11.
12 is configured such that when these are pressed, the lower end of the lever pressing portion 8a is locked by the rear edge portion 433 of the lock plate 43, but only the playback button 10 will be described later. When pressed in this manner, the claw 56 is configured to be locked by a stepped portion 56a formed on the claw 56.

Note that 49 in the figure is a projecting piece integrally formed on the right end portion of the lock plate 43.

To explain the locking and unlocking operations of the push buttons 8, 10, 11, and 12 other than the stop button 9 by the lock plate 43, first, when the play button 10 is pressed as shown in FIG. 'The bar pressing portion 10a climbs over the pawl 56 and is locked by the stepped portion 56a.

Note that even if the rewind button 8 and the fast forward button 11 are pressed in this state as shown in FIG.
does not come into contact with the claws 54 and 57, and the lock plate 43 is not operated at this time.

This makes it possible to press the rewind button 8 and fast forward button 11 while holding down the play button 10 (locked 5).
You can perform the review and cue operations described below.

Similarly, when the rewind button 8, fast forward button 11, and record button 12 are pressed as shown in FIGS. 19, 23, and 24, respectively, Ci these lever pressing portions 8a, 11a.

12a climbs over winter melons 54, 57, and 5B to lock plate 4
It is locked at the rear edge 43a of No. 3.

If the stop button 9 is pressed while the push buttons 8, 10.1L12 are locked, the operating portion 9a will come into contact with the pawl 55, causing the lock plate 43 to rotate significantly.
The locks of the push buttons 8, 10, 11 and 12 are released and they are respectively moved back.

This device enables one-touch recording as described later, so when the record button 12 is pressed while the playback button 10 is pressed, or when the playback button is pressed while the record button 12 is pressed. When 10 is pressed, the play button 10 and the record button 12 are unlocked.

Furthermore, when the play button 10 or the record button 12 is pressed while the rewind button 8 or the fast forward button 11 is being pressed, the lock of the rewind button 8 or the fast forward button 11 is released. Furthermore, when one of the rewind button 8 and fast forward button 11 is pressed while the other is pressed, the lock of the one that was pressed first is released. There is.

Next, details of the mode switching mechanism will be explained.

This is clearly illustrated in FIGS. 5-17.

First, a capstan 60 is pivotally supported at a predetermined position on the mechanical board 15, and a flywheel 61 is fixed to the lower end of the capstan 60.

This flywheel 61 has pulleys 62 above and below it.
,63.

is formed.

Further, an anti-rolling flywheel 64 is connected to the mechanical board 15 via a shaft 65 on the left side of the capstan 60.
It is pivoted on.

Note that a pulley 66 is also formed on this flywheel 64.

The left end of the mechanical board 15. A motor 6B is attached to the motor 6B, and a belt 6 is attached to the motor pulley 67 and the boos IJ 62 and 66 of the flywheel 6L64.
9 is twisted and wound at right angles as shown in the figure.

On the other hand, at the lower end of the supply reel shaft 17 is a two-stage boot IJ70.
．． 71 is fixed.

A pulley 72 is fixed to the upper side of the lower end of the take-up reel shaft 18, a pulley 73 is rotatably fitted to the lower part of the pulley 72, and a collar 74 is fixed to the lower part of the pulley 72. The fitted washer 75 and the above pulley.

The compression spring 76 interposed between the boot I and T3
J73 is always elastically pressed upward, and this pulley 7
3 and the above-mentioned pulley 12, the friction plate 77 made of felt or the like is always elastically pressed by a friction plate 77, forming a so-called limiter mechanism.

(See Figures 27 and 28).

A counter T8 is attached to a predetermined position on the mechanical board 15, and a pulley 80 fixed to the counter drive shaft 79 and the pulley 71 are interlocked by a belt 81.

Further, an intermediate shaft 82 is pivotally supported on the mechanical board 15 at a rear side position of the take-up reel shaft 18 .

A pulley 83 is fixed to this intermediate shaft 82, and this pulley 83 and the pulley 63 are interlocked by a belt 84.

Here, 86 is an idler that drives the take-up reel shaft 18 at a predetermined speed during playback and recording, which will be described later, and 81 is an idler that drives the take-up reel shaft 18 at a high speed during fast forward and cue times, which will be described later. Reference numeral 88 denotes an idler that is supplied during winding and review, which will be described later, and drives the part 17 in reverse at high speed.

These idlers 86, 8γ, and 88 are each constituted by a rubber roller, and the idler 86 is configured to be press-fitted between the pulley 73 and the boss portion 83a of the pulley 83 so as to be able to be separated therefrom.

Further, the idler 87 is configured in two stages, upper and lower, with an upper part 87a being press-fitted to the pulley 72, and a lower part 87b being press-fitted to the flywheel 61, respectively, so that they can be freely separated.

Furthermore, the idler 88 is configured to be press-fitted to and detached from the flywheel 61.

A link 89 having the idler 86 pivotally attached to its tip is pivotally supported via a pin 90 to a malfunction prevention lever 91 of a shut-off mechanism, which will be described later.

The malfunction prevention lever 91 is rotatably supported on the mechanical board 15 via a fulcrum pin 92, and includes an arm 91a integrally formed at one end thereof and a rear plate portion 16b of the head board 16. It is rotated clockwise in FIG. 5 by a tension spring 93 stretched between the rear end and a part of the rear end.

The clockwise rotation angle of the lever 91 is regulated by the arm 91a coming into contact with a stopper 94 integrally formed near the rear end of the rear plate portion 16b. .

On the other hand, the head board 16 is engaged with a pair of guide pins 96 implanted in the mechanical board 15 through a pair of elongated holes 9T, and is configured to be able to reciprocate back and forth in a conventionally known manner.
I'm here.

Further, 9B is a regeneration lever, and the rear end side of the regeneration lever 9B is pivotally supported by a link 100 via a pin 99.
Guide pin 10 whose front end side is implanted in mechanical board 15
1 through a long hole 102.

Note that the link 100 is pivotally supported on the mechanical board 15 via a fulcrum pin 103.

Therefore, the regeneration lever 98 is configured to be able to reciprocate in the front and back direction, and is urged to slide forward by a tension spring 104 whose one end is locked to the pin 99.

This reproduction lever 98 and the front plate part 1 of the head board 16
The head substrate 16 is connected to the head substrate 16 via a tension spring 105 stretched between a stopper 106 integrally formed on a part of the head substrate 6a.
is configured to reciprocate following the reproduction lever 98.

Note that the lever pressing portion 10a of the regeneration button 10 is in contact with a part of the front end surface 98a of the regeneration lever 98, and the stopper 106 is in contact with this front end surface 98a.

A link 107 with the idler 81 pivotally attached to the tip is pivotally supported to the tip of the link 109 via a pin 108,
This link 109 is pivotally supported on the mechanical board 15 via a fulcrum pin 110.

Further, the idler 88 is pivotally connected to one end of a link 112 that is pivotally supported on the mechanical board 15 via a fulcrum pin 111.

A boo IJ 113 is integrally formed on this idler 88, and this pulley 113 and the pulley 70 are interlocked by a belt 114.

The belt 114 urges the link 112 to rotate counterclockwise in FIG.

Further, 116 is a recording lever, and this recording lever 116
is rotatably supported on the mechanical board 15 via a fulcrum pin 117.

The recording lever 116 is biased to rotate clockwise in FIG. has been done.

Further, a roller 118 having an inverted conical shape and pivotally mounted on one end 116a thereof is in contact with a part of the front end surface 16d of the front plate portion 16a of the head substrate 16.

The other end of this recording lever 116 is connected to the switch operating lever 1 via a link 119 and a pair of pins 120, 121.
22.

This switch operating lever 122 is rotatably supported on the mechanical board 15 via a fulcrum pin 123, and is adapted to operate a recording/playback circuit changeover switch 125 by a plate spring 124 fixed to the other end. It is configured.

The switch operating lever 122 is biased to rotate counterclockwise in FIG. 5 by a tension spring 126, one end of which is locked on the other end.

Further, 128 is a fast forward lever, and this fast forward lever 1
Reference numeral 28 denotes a guide pin 129 implanted in the mechanical board 15.
The mechanical board 15 is engaged with the mechanical board 15 through a long hole 130, and guided by a slide guide (not shown) formed integrally with the mechanical board 15, so that it can freely reciprocate in the front and rear directions.

The fast-forwarding lever 128 is urged to slide forward by a tension spring 131 having one end locked thereto, and its front end 128a is brought into contact with the lever pressing portion 11a of the fast-forwarding button 11.

Note that a U-shaped notch 132 is formed at the rear end of this fast-forwarding lever 128, and the link 1 is inserted into this notch 132.
One end 133a of 33 is engaged.

This link 133 is pivotally supported by the mechanical board 15 via a fulcrum pin 134, and the other end is connected to the link 109.
is in contact with the other end.

Further, a tension spring 13 is connected between these links 133 and 109.
5 is stretched.

Further, an arm 136 integrally extending rearward from the right end of the head substrate 16 connects to the other end 133 of the link 133.
It is configured so that it can come into contact with b.

Further, 138 is a rewind lever, and this rewind lever 1
38 is engaged with a pair of guide pins 139 implanted in the mechanical board 15 through a pair of elongated holes 140, and is configured to be able to reciprocate in the front and back direction.

The rewind lever 138 is biased to slide forward by a tension spring 141, one end of which is locked to the front end 138a of the rewind lever 138.
is in contact with the lever pressing portion 8a.

Further, a stopper 142 is integrally formed at the rear end of the rewind lever 138.

A leaf spring 143 fixed to the other end of the link 112 is pressed against the stopper 142.

Note that 144 is connected to the mechanical board 15 via a fulcrum pin 145.
This is a link that is pivoted to the
44a is in contact with the lever pressing portion 8a of the rewind button 8, and the other end 144b is configured to be in contact with a stopper 146 integrally formed on a part of the front plate portion 16a of the head substrate 16. There is.

Further, 148 is a brake lever, and this brake lever 148 is engaged with a pair of guide pins 149 implanted in the mechanical board 15 through a pair of elongated holes 150, so that it can freely reciprocate in the front and rear direction. There is.

A plate spring 151 is fixed to the rear end 148b of the brake lever 148 (7), and a pair of brake pads 152 fixed to both ends of the plate spring 151 are connected to the both bools IJ7.
0 and 72 so that they can be pressed and separated.

The brake lever 148 is biased to slide forward by a tension spring 153, one end of which is locked.

On the other hand, a link 154 is pivotally supported on the shaft 65, and one end 154a of this link 154 abuts against a stopper 155 integrally formed with a portion of the brake lever 148.

Also, the mechanical board 15 is located on the left side of this linri 154.
A link 156 is pivotally supported via a fulcrum pin 157, and one end 156a of this link 156 is connected to the link 15.
4 is in contact with the other end 154b.

The other end 156b of this link 156 is in contact with a stepped portion 158 formed on the rewind lever 138.

Further, the rear end 98b of the regeneration lever 98 is connected to the link 15.
It is configured so that it can come into contact with one end 154a of 4.

Further, the rear end 138b of the rewinding lever 138 is configured to be able to come into contact with a stopper 159 formed integrally with a part of the switch operating lever 122 (7).

Reference numeral 160 denotes an erase head operating lever, and this lever 160 is pivotally supported on the mechanical board 15 via a fulcrum pin 161.

One end 160a of this lever 160 is in contact with a pin 162 hanging down from the erase lever 26.5The other end of this lever 160 is connected to the switch operating lever 122 via the pin 121. .

Further, 164 is an accidental erasure prevention claw detection lever.

This detection lever 164 detects the presence or absence of the accidental erasure prevention claw on the cassette 2, as is conventionally known, by means of a detection piece 164a formed integrally therewith.

This detection lever 164 is pivotally supported on the mechanical board 15 via a fulcrum pin 165, and is biased to rotate counterclockwise in FIG. 5 by a tension spring 166, one end of which is locked.

Note that the detection lever 164 is configured such that the rear end 122a of the switch operating lever 122 can come into contact with one end surface 164a.

Further, 168 is a malfunction prevention lever, and this lever 16
8 is pivotally supported on the mechanical board 15 via the fulcrum pin 165.

This lever 168 is biased to rotate counterclockwise in FIG. .

Further, the rear end 122a of the switch operating lever 122 is configured to be able to come into contact with the other end surface 168b of this lever 168.

Reference numeral 111 denotes an ejection prevention lever, and this lever 171 is engaged with a pair of guide pins 112 implanted in the mechanical board 15 via an elongated hole 113, so as to be able to reciprocate in the front and back direction.

Note that this lever 171 is connected to the left end portion 1 of the head substrate 16 between a pair of stoppers 174 integrally formed therewith.
6e.

Next, the switching status of each mode will be explained based on the structure described above.

[Stop mode]

This stop mode is clearly shown in Fig. 15. At this time, all members are moving backwards as shown in the figure, and both brake pads 1
52 is press-fitted to the circumferential surfaces of both boos IJ70 and 72, and brakes are applied to both reel shafts 17 and 18.

[Playback mode]

This playback mode is clearly illustrated in FIGS. 6 and 7.

When the playback button 10 is pressed as described above, the lever pressing part 10
a pushes the playback lever 98 backward.

As a result, the head substrate 16 is pulled through the tension spring 105, and the head substrate 16 is elastically and
It moves forward (slides backward) against the force 04.

At this time, when the head board 16 has moved a predetermined distance, the rear end 98b of the regeneration lever 98 is moved to the one end 154 of the link 154.
In order to abut and push the stopper 155 of the brake lever 148 via a, the brake lever 148 is moved forward against the tension spring 153, and first both brake pads 15
2 are spaced apart from both boos IJ 70, 72.

Then, the forward movement of the brake lever 148 turns on a power switch (not shown).

When the motor 68 is activated by the power switch,
Both flywheels 61 and 64 are rotated in the arrow directions via the motor pulley 61, belt 681, and pulleys 62 and 66, respectively, and the capstan 60 is driven.

Note that when the capstan 60 is driven, the pulley 83 is rotated in the direction of the arrow via the pulley 63 and the belt 84.

Therefore, due to the forward movement of the head substrate 16, the tension spring 91
The malfunction prevention lever 91 is rotated clockwise via the
Approach 3a.

At this time, as the head board 16 moves forward, one end 160a of the erasing head actuating lever 160 presses the pin 162 relatively backward, so the erasing head lever 26 on the head board 16 moves counterclockwise against the tension spring 30. rotated in the direction.

As a result, the recording/reproducing head 24 and the pinch roller 25 are moved forward by the forward movement of the head substrate 16, but the erasing head 23 is held at the backward movement position.

Then, when the head substrate 16 reaches the forward movement end position, the recording/reproducing head 24 . and a pinch roller 25 are inserted into the cassette 2 in a conventional manner.

The recording/reproducing head 24 comes into contact with the tape in the cassette 2, and almost at the same time as the pinch roller 25 presses the tape against the capstan 60, the idler 86 is pressed against the pulley 73 and the boss portion 83a of the pulley 83.

As a result, almost at the same time when the tape is driven to run at a predetermined speed by the capstan 60, the rotational force of the pulley 83 is applied to the idler 86. Pulley 13, friction plate TI, pulley 72
is frictionally transmitted to the take-up reel shaft 18 via the take-up reel shaft 18, which drives a take-up reel hub (not shown) in the cassette 2 in a conventional manner.

The desired regeneration is performed as described above, but as the brake lever 148 moves forward, the malfunction prevention lever 168 is rotated counterclockwise by the tension spring 169 as shown in the figure.

As a result, even if an attempt is made to accidentally press the record button 12 in the playback mode, the rear end 122a of the switch operating lever 122 will come into contact with the rear end surface 168b of the malfunction prevention lever 168, and the clockwise rotation of the lever 122 will be prevented. To be prevented.

As a result, the record button 12 cannot be pressed.

This prevents malfunctions such as accidentally pressing the record button 12 in the playback mode.

[Recording mode]

This recording mode is clearly illustrated in FIGS. 8-11.

Note that to switch to this recording mode, it is sufficient to press only the record button 12, and there is no need to press the playback button 10 at the same time.

At this time, if the accidental erasure prevention claw 176 of the cassette 2 is not broken off, the detection piece 164a of the accidental erasure prevention claw detection lever 164 is pushed by the claw 116, and the detection lever 164 is pulled as shown by the solid line in FIG. The detection lever 164 is rotated clockwise against the spring 166, but when the accidental erasure prevention claw 116 is broken off, this detection lever 164 is rotated clockwise against the spring 166.
The state shown by the dashed line in the figure is maintained.

Therefore, at this time, even if you try to press the record button 12 unexpectedly,
The rear end 122a of the switch actuation lever 122 comes into contact with the other end surface 164b of the detection lever 164, and the lever 122
As a result, the record button 1 is prevented from rotating clockwise.
2 cannot be pressed, and so-called erroneous erasure is prevented.

Therefore, switching to this recording mode is possible only when the accidental erasure prevention claw 116 of the cassette 2 is not broken off.

When the recording button 12 is pressed as described above, the lever pressing part 12
a pushes one end 116a of the recording lever 116.

As a result, the roller 118 pushes the head substrate 16, so that the head substrate 16 is moved forward in the same manner as described above.

However, as clearly shown in FIG.
In order to press d, the head substrate 16 is pushed backward by the cam action at this time and receives a downward pressing force.

Therefore, when the head board 16 moves forward, the head board 16 is always pressed against the upper surface side of the mechanical board 15 and is moved very effectively. No floating occurs.

Note that in this device, as described above, the rear plate portion 1 of the head substrate 16
6b is configured to be flush with the low flat plate portion 15b of the mechanical board 15, unexpected floating of the head board 16 may cause serious alignment.

Therefore, by preventing the head substrate 16 from floating, the head substrate 16 can be reciprocated extremely smoothly in this ultra-thin device, which is of great significance.

When the head board 16 is moved forward, the stopper 106 pushes the regeneration lever 98.
8 is pushed against the tension spring 105 in the same way as in the second mode described above.

As a result, the tape runs in the same way as in the playback mode, but at this time, since the recording lever 116 is rotated counterclockwise against the tension spring 127, the recording lever 116 is rotated counterclockwise against the tension spring 127. is rotated clockwise on the tension spring 126, and the circuit changeover switch 125 is switched to the recording mode side by the leaf spring 124.

Also, at this time, since the erasing head operating lever 160 is rotated counterclockwise, the erasing head 23 moves forward together with the recording/reproducing head 24 and is inserted into the cassette 2.

As described above, the desired recording is performed.

As the head board 16 is moved forward, the arm 136
approaches the other end 133b of the link 133.

As a result, even if you try to press the fast forward button 11 unexpectedly in the recording mode, the other end 133b of the link 133
36 and prevents the link 133 from rotating clockwise, resulting in the inability to press the fast forward button 11.

Similarly, when the switch operating lever 122 is rotated clockwise, the stopper 159 is moved to the rewind lever 1.
38 approaches the rear end 138b.

As a result, even if you accidentally try to press the rewind button 8 in the recording mode.

Since the rear end 138b of the rewind lever 138 comes into contact with the stopper 159 of the switch operating lever 122 and is prevented from moving forward, the rewind button 8 cannot be pressed as a result.

Therefore, malfunctions such as accidentally pressing the fast forward button 11 and the rewind button 8 in the recording mode are prevented.

[Fast forward mode]

This fast forward mode is clearly illustrated in FIGS. 12 and 13.

When the fast forward button 11 is pressed as described above, the lever pressing part 1
1a pushes the fast forward lever 128 backward against the tension spring 131.

As a result, the link 133 is rotated clockwise, and the link 109 is rotated counterclockwise via the tension spring 135.

Idler 81 is crimped between pulley T2 and flywheel 61 via link 107.

At this time, the stepped portion 137 of the fast-forwarding lever 128 comes into contact with the front end 148b of the brake lever 148 and pushes it backward, so that the same operation as in the playback mode described above is performed.

However, at the time of leverage, the rotational force of the flywheel 61 is transmitted to the boot 912 via the idler 8T, so the 1-take-up reel shaft 1B is driven at high speed in the direction of the arrow.

The tape is therefore wound at a high speed and the desired rapid forwarding is achieved.

Note that in this fast-forward mode, the malfunction prevention lever 168 is rotated counterclockwise in the same way as in the playback mode described above.
Since the switch operating lever 122 is prevented from rotating clockwise, the record button 12 cannot be pressed unexpectedly in this fast-forward mode as in the playback mode.

[Rewind mode]

This rewind mode is clearly illustrated in FIGS. 14 and 15.

When rewind button 8 is pressed as described above. The lever pressing part 8a
pushes the rewind lever 138 backward against the tension spring 141.

As a result, the stopper 142 rotates the link 112 clockwise via the leaf spring 143, so that the idler 88
is crimped onto the flywheel 61.

Note that the stepped portion 158 of this original note return lever 138 is the link 1.
56 and rotates the link 156 clockwise, the link 154 is rotated counterclockwise, and one end 154a of the link 154 is pressed against the brake lever 1.
48 and pushes it backward.

As a result, the same operation as in the reproduction mode described above is performed.

However, at this time, the rotational force of the flywheel 61 is transmitted to the pulley 70 via the idler 88, pulley 113, and belt 112, so the supply reel shaft 11 is driven in the direction of the arrow at high speed and in reverse.

Therefore, the tape is rewound at a high speed to achieve the desired rewound.

Note that in this rewind mode, the malfunction prevention lever 168 is rotated counterclockwise in the same way as in the playback mode described above.
Since the switch operating lever 122 is prevented from rotating clockwise, the record button 1 is still pressed even in this rewind mode.
I can't press 2 unexpectedly.

[Cue mode]

This cue mode is clearly illustrated in FIG.

When the fast forward button 11 is pressed in the playback mode described above, the fast forward lever 128 is pushed backward and the link 133 is rotated clockwise.

As a result, the link 109 is rotated counterclockwise via the tension spring 135, and the idler 80 is moved to the flywheel 61.
and the pulley 72, and the take-up reel shaft 18 is driven at high speed in the direction of the arrow.

At the same time, the other end 133b of the link 133 comes into contact with the arm 136 of the head board 16 and pushes it back forward.

As a result, the head substrate 16, which was being moved forward, is moved to the tension spring 1.
Because it is pushed back a little towards the front against 05.

The recording/reproducing head 24 and the pinch roller 25 on the head substrate 16 are also pushed back slightly forward, and the recording/reproducing head 24 maintains contact with the tape, but the pinch roller 25 separates from the capstan 60.

Also, at this time, the stopper 94 of the head board 16 comes into contact with the arm 91a of the malfunction prevention lever 91 and presses it.
When this lever 91 is rotated counterclockwise, the idler 8
6 is spaced apart from the pulley 73 and the boss portion 83a of the pulley 83.

As described above, only while the record button 12 is pressed, the tape is wound at high speed while being played back, and the desired cue operation is performed.

Note that when the record button 12 is released, it is moved backward as described above, and at the same time as the idler 87 separates from the flywheel 61 and pulley 72, the head base plate 16 returns to the forward movement position.

As a result, the reproduction mode described above is automatically switched to perform the desired reproduction.

[Review mode]

This review mode is clearly illustrated in Figure 1T.

When the rewind button 8 is pressed in the playback mode described above, the rewind lever 138 is pressed and the link 112 is rotated clockwise.

As a result, the idler 88 is pressed against the flywheel 61, and the supply reel shaft 17 is driven reversely at high speed in the direction of the arrow.

At the same time, the link 144 is rotated clockwise so that the other end 144b is connected to the stopper 1 of the head board 16.
46 and push it back forward.

As a result, the head substrate 16, which was being moved forward, is moved to the tension spring 1.
05 and was pushed back a little towards the front.

The same operation as in the queue mode described above is performed.

As described above, only while the rewind button 8 is pressed, the tape is rewound at high speed while being played back, and the desired review operation is performed.

As in the cue mode, when the rewind button 8 is released, the mode is automatically switched to the playback mode.

26 to 34 show a characteristic shutoff mechanism.

This shutoff mechanism is attached to the lower end portion of the take-up reel shaft 18, and includes a first detection lever 17.
7. Second detection lever 178, first shut-off lever 1
79, second shut-off lever 180, third shut-off lever 181. Levers such as the malfunction prevention lever 91 and malfunction prevention plate 182 are provided.

The first detection lever 177 is fitted around the outer periphery of the lower end portion 74a of the collar 74, which is fixed to the lower end side of the take-up reel shaft 18, so as to be relatively rotatable.

Note that there is a bushing 1 at the bottom end of the take-up reel shaft 18.
85 is fixed, and the flange 18 of the bush 185
The malfunction prevention plate 182 is fitted to the outer circumferential position of this bushing 185 on 5a so as to be relatively rotatable.

The first detection lever 171 and the malfunction prevention plate 1
A coiled spring 186 wound several times around the outer periphery of the bushing 185 is interposed between the upper end 186 of the coiled spring 186 and
a is locked to the first detection lever 1T7, and the lower end 186b is locked to the malfunction prevention plate 182.

The first detection lever 177 is constantly pressed upward by the compressive repulsive force of the coiled spring 186, and the collar 74 is pressed upward at all times.
It is press-fitted to the lower surface of a flange portion 74b that is integrally formed with the flange portion 74b.

Therefore, this first detection lever 177 is connected to the take-up reel shaft 18.
When the collar 74 rotates, a frictional driving force (however, this frictional force is very weak) is obtained from the outer peripheral surface of the lower end 74a of the collar 74 and the lower surface of the collar 74b, which urges the take-up reel shaft 18 to rotate in the rotational direction. is configured to be

The coiled spring 186 is connected to the first detection lever 1 as described above.
At the same time as pressing 77 upward, this first detection lever 1
17 in the counterclockwise direction in FIG. 26, and the malfunction prevention plate 182 in the clockwise direction.

Note that a notch 187 cut out on one side is formed at the end of the first detection lever 177.
7 has a first recess 188. and a second recess 189' are formed.

Note that reference numeral 190 denotes a top portion provided closer to the tip of the lever than the first recess 188, and this top portion 190 extends from the straight line connecting the first recess 188 and the take-up reel shaft 18 to the winding position indicated by the arrow in FIG. It protrudes in the 18th rotation direction of the reel shaft.

The second detection lever 178 is rotatably supported on the mechanical board 15 via a fulcrum pin 191.

A detection pin 192 is integrally protruded from one end 178a of the second detection lever 178.
Is the above notch 1B? It is configured to be able to freely move back and forth within.

Further, the first shut-off lever 179 is rotatably supported via a fulcrum pin 193 at a position on the other end 178b side of the fulcrum pin 191 of the second detection lever 178.

One end 179 of this first shut-off lever 179
By the tension spring 194 whose one end is locked at the a side position,
This first detection lever 179 is rotated counterclockwise in FIG. 26 about the fulcrum pin 193, and the fulcrum pin 1
The second detection lever 178 is activated by the spring force applied to the portion 93.
It is also rotated counterclockwise in FIG. 26 about the fulcrum pin 191.

Note that one end 179a of this first shut-off lever 119
A partial gear 195 having an arc shape centered on the fulcrum pin 193 is formed on the end face of the gear.

On the other hand, a gear 196 is integrally formed at the end of the boss portion 83a of the pulley 83 attached to the intermediate shaft 82, and this gear 196 includes reduction gears 197, 198,
199 and 200 are linked sequentially.

The gears 197 and 198 and 199 and 200 are integrally molded in two stages, upper and lower, and are supported by the mechanical board 15 via shafts 201 and 202, respectively.

Therefore, the partial gear 195 is the gear 2 at the final stage of reduction.
It is configured to be able to engage and disengage freely.

On the other hand, a cam 203 is integrally formed on the lower surface of the gear 199, and this cam 203 is connected to the second detection lever 118.
It is configured to be rotated while contacting the side surface of the other end 178b.

The second shut-off lever 180 has an L-shape and is pivotally supported on the mechanical board 15 via a fulcrum pin 205.

One end 180 of this second shut-off lever 180
a to the other end 179b of the first shut-off lever 179;
The second shut-off lever 180 is configured to be able to come into contact with it.
One end 181a of the third shut-off lever 181 is connected to the other end 180b via a pin 206.

Note that this third shut-off lever 181 extends to one end position of the lock plate 43, and is engaged with a guide pin 207 implanted in the mechanical board 15 through a long hole 213, so that it can be moved in the front-rear direction. It is configured to be able to freely reciprocate.

The other end (front end) 181b of the third shut-off lever 181 is configured to be able to come into contact with the protrusion 49 of the lock plate 43.

On the other hand, two arms 208 and 209, which are a first locking part and a second locking part, are integrally formed on the other end side of the malfunction prevention lever 91.
is configured to be able to come into contact with one end 178a of the second detection lever 118 and an arm 210 integrally formed with the malfunction prevention plate 182.

The tip 210a of the arm 210 is bent into a substantially L-shape so that the idler 88 can come into contact with the lower end of the idler shaft 211 which is pivotally connected to the link 112.

Note that, as a matter of course, this idler shaft 211 is extended downward to a predetermined length.

Further, the third shut-off lever 181 is urged to slide forward by a tension spring 212, one end of which is locked.

Furthermore, the other end 119b of the first shut-off lever 119
is in contact with one end 180a of the second shut-off lever 180, so that the rotation angle of the first shut-off lever 179 by the tension spring 194 is regulated.

Next, the operation of the above-mentioned shutoff mechanism will be explained.

As is well known in the art, this shutoff operation is performed when the tape reaches the end in the playback mode or the record mode, and the running of the tape is automatically stopped.

FIG. 26 shows the stop mode. At this time, the malfunction prevention lever 91 is rotated counterclockwise as described above, and its arms 208 and 209 are connected to one end 118a of the second detection lever 118 and the malfunction prevention lever 91. The second detection lever 118 is rotated clockwise against the tension spring 194 by contacting the arms 210 of the prevention plate 182, and the malfunction prevention plate 182 is rotated counterclockwise.

Note that the counterclockwise rotation of the malfunction prevention plate 182 twists the coil spring 186, causing the first detection lever 117 to rotate counterclockwise, while the second detection lever 118 rotates clockwise. , the detection pin 192 has a notch 18γ
In the stop mode, the first detection lever 177 is brought into contact with the detection pin 192.
The detection lever 177 is forcibly rotated counterclockwise, the second detection lever 17B is forcibly rotated clockwise, and the first detection lever 177 is forcibly brought into contact with the detection pin 192. At the same time, this detection pin 192 is inserted into the notch 1.
81 and is pushed out to an outer position than at least the first recess 188 .

However, this means that the detection pin 192 is inserted into the second recess 189 of the notch 181 immediately before starting the playback mode or recording mode.
This prevents the shutoff operation from being performed unexpectedly due to the shutoff operation being described later.

This is because in the stop mode, the rotation of the take-up reel shaft 18 is stopped, and the first detection lever 111 is in a state where it can freely rotate in any direction around the take-up reel shaft 18.

On the other hand, it is unclear at what position the cam 203 is stopped.

For this reason, the first detection lever 111 and the second detection lever 17B
It is also expected that the detection pin 192 is in the position indicated by the chain line in FIG. 26, and the detection pin 192 is depressed into the second recess 189.

However, in the levered state, the partial gear 195 engages with the gear 200 as shown by the chain line, and in this state, the playback mode or recording mode is started, and when the motor 68 is activated, a shutoff operation, which will be described later, is performed. It turns out.

Therefore, as soon as the playback button 10 or the record button 12 is pressed, these pushbuttons 10 and 12 are unlocked, resulting in a so-called shut-off malfunction.

FIG. 32 shows the state when the tape is running in the play mode or the record mode.

First, in this reproduction mode or recording mode, as described above, the head substrate 16 is moved forward and the malfunction prevention lever 91 is rotated clockwise, so at this time both arms 208.2
09 are spaced apart from one end 118a of the second detection lever 178 and the arm 210 of the malfunction prevention plate 182, respectively.

On the other hand, at this time, the idler 86 is connected to the pulley 73 and the pulley 8.
1 take-up reel shaft 1.
8 is being rotated at a predetermined speed in the direction of the arrow.

At this time, the rotational force of the motor 68 that is being transmitted to the boot 983 is being transmitted to the gear 200 via the gears 196, 197, 198, and 199,
03 is being rotated at low speed in the direction of the arrow.

While the take-up reel shaft 18 is rotating in the direction of the arrow, the first detection lever 111 is urged to rotate in the same direction by the aforementioned frictional driving force.

On the other hand, due to the rotation of the cam 203, this cam 203
Since the detection lever 118 rotates by intermittently contacting the side surface of the other end 178b, the second detection lever 118 rotates alternately clockwise and counterclockwise in conjunction with the cam 203 and in cooperation with the tension spring 194. This results in a reciprocating motion.

However, the reciprocating stroke S1 of the second detection lever 178 at this time is within the angular range shown by the solid line and the chain line in FIG. 32.

That is, when the second detection lever 178 is kicked by the cam 203 and rotated clockwise to the maximum, the detection pin 192
reaches the position of the solid line.

At this time, the top 190 of the first detection lever 177 is connected to the detection pin 1.
92 pushes, the first detection lever 177 is rotated in the opposite direction of the arrow against the aforementioned frictional driving force, and becomes the state shown by the solid line.

As the cam 203 continues to rotate, this cam 20
3 leaves the second detection lever 118, the second detection lever 178 is rotated counterclockwise by the tension spring 194, and the detection pin 192 starts moving toward the inner side of the notch 181.

However, at this time, since the first detection lever 177 is always urged to rotate in the direction of the arrow, it rotates in the direction of the arrow toward the position indicated by the chain line as the detection pin 192 moves.

As a result, the detection pin 192 moves from the top 190 to the first recess 18.
By completely entering the first recess 188 as shown by the chain line, the notch 181 is prevented from moving further to the inner side.

At this moment, the tension spring 19 of the second detection lever 178
4 is prevented from rotating counterclockwise.

As a result of the above, while the tape is running in the playback mode or the recording mode, the second detection lever 178 has a stroke S or less.

This means that it is constantly reciprocating within the angular range of .

At this time, as the second detection lever 17B reciprocates, the partial gear 195 of the first shut-off lever 119 is moved toward and away from the gear 200. The partial gear 195 is configured such that it cannot engage with the gear 200 even if it is turned most counterclockwise.

FIG. 33 shows the instant of the shutoff operation.

When the tape ends in the playback mode or recording mode described above and the rotation of the one-winding reel shaft 18 stops, the frictional driving force that has been applied to the first detection lever 177 is also released, and at this moment the first detection lever 177 is in a state where it can freely rotate in any direction around the take-up reel shaft 1B.

In contrast, the cam 203 continues to rotate.

The second detection lever 118 continues to perform the previous reciprocating motion.

When the detection pin 192 is once moved to the position indicated by the chain line, the detection pin 192 kicks the top 190 of the first detection lever 17T, and the first detection lever 177 is moved back to the position shown in the figure. It is then stopped at that position.

However, after levering the second detection lever 178, the tension spring 194
When the detection pin 192 is rotated counterclockwise by 2 into the recess 189.

That is, at this time, the second detection lever 118 has a large stroke S that is larger than the previous reciprocating stroke S1.
2, it will be rotated counterclockwise.

As a result, the first shut-off lever 179 is moved significantly upward, and its partial gear 195 is engaged with the gear 200 as shown by the solid line.

However, at this moment, the partial gear 195 is moved by the gear 200.
is driven, and the first shut-off lever 179 is forcibly rotated clockwise as shown by the chain line around the fulcrum pin 193 against the tension spring 194.

As a result, the third shutter-off lever 181 is moved to the second position via the second shutter-off lever 180 against the tension spring 212.
It is drawn backwards as shown by the solid line in Figure 9.

Then, the other end 181b pulls the protrusion 49 of the lock plate 43 backward, so the lock plate 43 is rotated downward against the tension spring 48, and the playback button 10 or record button 12, which has been locked until now, is locked. is released.

If these push buttons 10 and 12 are released, the above-mentioned stop mode is entered and the tape drive is stopped.

FIG. 34 explains the malfunction prevention effect in the review mode.

In the review mode, the idler 88 is pressed against the flywheel 61 as described above, and the tape is rewound at high speed.

At this time, the take-up reel shaft 18 is driven by the tape and reversely rotated in the direction of the arrow, opposite to that in the reproduction mode and recording mode.

On the other hand, since the aforementioned frictional driving force is applied to the first detection lever 177 as long as the take-up reel shaft 18 rotates, in this review mode, this first detection lever 17
7 is rotationally energized in the rotational direction of the take-up reel shaft 18, that is, in the opposite direction to that in the reproduction mode and recording mode.

If the first detection lever 177 is reversely rotated in the direction of the arrow 5, this detection lever 177 will be separated from the detection pin 192.
It is obvious from looking at the fire that it will be moved to the position shown in the diagram.

If this state occurs, the above-mentioned shut-off operation will be unexpectedly performed at that moment.

Therefore, in the review mode, the system is always placed in a situation where a malfunction of the shutoff is possible, which is really inconvenient.

However, according to the present device, in the review mode, when the idler 88 is pressed onto the flywheel 61, the lower end of the idler shaft 211 touches the arm 2 of the malfunction prevention plate 182.
This malfunction prevention plate 182 is rotated counterclockwise in order to come into contact with and push the tip 210a of 10.

Then, the malfunction prevention plate 182 is rotated counterclockwise, and the first detection lever 177 is rotated counterclockwise via the five-helical spring 186, that is, in the opposite direction to the direction of the arrow, which is the rotation direction of the take-up reel shaft 18. be moved.

In other words, even in the review mode, the first detection lever 11
7 is elastically biased to rotate in the same direction as in the playback mode and the record mode, thereby performing the same function as in the playback mode and the record mode.

Therefore, even in this review mode, the second detection lever 178 is reciprocated within the angular range of the stroke S1, making it possible to prevent the aforementioned shutoff malfunction.

FIGS. 35 to 37 show the characteristic eject mechanism portion.

The eject button 13 is fixed on one end 214a of a leaf spring 214.

The other end 214b of the leaf spring 214 is crimped at a predetermined position on the mechanical board 15 by a pair of crimping pins 215.

On the other hand, an eject lever 216 is pivotally attached to the mechanical board 15 at a lower position of one end 214a of the leaf spring 214 via a horizontal fulcrum pin 217 so as to be freely rotatable in the vertical direction.

This eject lever 216 is connected to the fulcrum pin 21.
It is rotated clockwise in FIG. 36 by a coiled spring 218 wound in seven parts, and is positioned horizontally with its tip 216a in contact with the mechanical board 15.

The eject lever 216 is inserted into the lower side of the cassette 2 mounted on the cassette mounting section 6, and the other end 216b is connected to one end 214a of the leaf spring 214.
is in contact with the bottom of the

Further, the eject prevention lever 111 is arranged perpendicularly to the eject lever 216,
When this is moved forward, its tip 171a is configured to overlap the tip 216a of the eject lever 216.

After completing the desired recording or playback operation, open the opening/closing lid 7 and press the eject button 13 as shown by the chain line in FIG.
14a pushes the other end 216b of the eject lever 216 downward.

As a result, this eject lever 216 moves to the fulcrum pin 217.
The cassette 2 is rotated upward against the coil spring 218, and its tip 216a kicks up the lower surface of one end of the cassette 2.

As a result, the cassette 2 is ejected above the cassette mounting section 6.

Note that when you release your finger from the eject button 13 after ejecting the cassette, the eject button 13 is moved upward by the leaf spring 214, and the eject lever 216 is moved upward by the coil spring 2.
18, it is moved back downwards.

The leaf spring 214 serves both as a support member for the eject button 13 and as a spring member for backward motion.

Not only is the structure very simple, but the space factor is also very good, which greatly contributes to making the entire cabinet 3 thinner.

The ejection prevention lever 171 is moved forward in conjunction with the forward movement of the head substrate 16 in the above-described playback mode and recording mode, so that its tip 171a overlaps the tip 216a of the eject lever 216. Therefore, in the reproduction mode and the recording mode, even if an attempt is made to press the eject button 13, the eject prevention lever 111 prevents the eject lever 216 from rotating upward.

Therefore, as a result, the eject button 13 cannot be pressed in the playback mode and the record mode, and it is possible to prevent malfunctions such as accidentally ejecting the cassette 2 in the middle of the playback mode and the record mode. .

The invention is as described above.

(a) A detection member that is rotatably biased in a predetermined direction by rotation of an IJ reel shaft, and that the bias is released when the rotation of the reel shaft is stopped, and that has a first recess and a second recess.

(b) A drive member that is constantly driven by a motor.

(c) It is reciprocated by the driving member 1, and when the reel shaft is rotating, it reciprocates within the first recess with a first stroke, and when the reel shaft is stopped, it moves reciprocatingly within the second recess. A reciprocating member having a pin that reciprocates with two strokes.

(d) A lock plate actuating member that is activated when the reciprocating member reciprocates in the second stroke to release the lock plate of the playback button or the record button.

In a shut-off mechanism for a recording/playback device, which releases the lock of a playback button or a record button when the rotation of a reel shaft stops due to the tape end during playback or recording.

(e) A head substrate that is in a first position when stopped and is slid from the first position to a second position when the playback button or the record button is operated.

(f) The head substrate is rotated from the first position to the second position in conjunction with the sliding movement of the head substrate from the first position to the second position, and and a malfunction prevention lever having two engaging portions, the first engaging portion of the malfunction prevention lever being in the first position when stopped causes the pin of the reciprocating member to move to the first position of the detection member. 2. A shutoff mechanism in a recording/reproducing device, characterized in that the shutoff mechanism is configured to prevent the detection member from moving into the second recess and to rotationally urge the detection member in the predetermined direction by the second engagement portion. .

Therefore, according to the present invention, it is possible to reliably prevent the reciprocating member from unexpectedly reciprocating with the second stroke at the moment the playback button or record button is pressed in the stopped state, resulting in a shutoff malfunction. It can be prevented and highly reliable.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an embodiment in which the present invention is applied to a cassette tape recorder, and FIG. 1 is an overall perspective view;
Figure 2 is an exploded perspective view of the main parts showing the relationship between the mechanical board and the head board, and Figure 3 is the assembled state.
Figure 4 is an enlarged cross-sectional view taken along line IV-IV in Figure 2, Figure 5 is an enlarged plan view showing the stop mode with the mechanical board removed, Figure 6 is FIG. 1 is an enlarged plan view showing the reproduction mode relationship with the mechanical board removed. FIG. 8 is an enlarged plan view showing the recording mode relationship with the mechanical board removed. is a perspective view of the same as above, 1st
Figure 0 is a sectional view taken along the line X-X in Figure 8, Figure 11 is an enlarged partially cutaway plan view showing the relationship between the cassette's accidental erasure prevention claw and the recording button, and Figure 12 is a mechanical board showing the relationship between fast forward mode. Fig. 13 is an enlarged plan view shown with the parts removed, and Fig. 13 is a perspective view of the same as above.
Figure 4 is an enlarged plan view showing the rewind mode relationship with the mechanical board removed, Figure 15 is a perspective view of the same as above, and Figure 16 is an enlarged plan view showing the cue mode relationship with the mechanical board removed. , Fig. 17 is a review mode related Fig. 18 is a partially cutaway enlarged perspective view showing the lock plate and push button, and Fig. 19 is a view of the first
Figure 8 is a cross-sectional view taken along the line XIX-XIX, Figure 20 is a cross-sectional view taken along the line 18, Figure 21 is a cross-sectional view taken along the line XXI-XXI in Figure 18, and Figure 22 is a cross-sectional view taken along the line -xxu shown in Figure 18. Drawing, 2nd
Figure 3 is a sectional view taken along the line 18°C, Figure 24 is an enlarged exploded perspective view of the lock plate, and Figure 25 is an enlarged cross-section of the main part showing the relationship between the push button and the lock plate at the time of cue or review. Figure 26 is an enlarged plan view showing the shutoff mechanism with the mechanical board removed, and Figure 27 is Figure 26.
Line sectional view, Figure 28 is an exploded perspective view of the same as above, Figure 29 is an enlarged plan view showing the relationship between the shutoff mechanism and the lock plate with the mechanical board removed, and Figure 30 is the right side of Figure 29. 31 is a perspective view of the same as above, FIGS. 32 to 34 are enlarged plan views showing the operation of the shutoff mechanism with the mechanical board removed, and FIG. 35 is an enlarged plan view showing the eject mechanism. 36 is a sectional view taken along the line XXXVI-XXXVI in FIG. 35, and FIG. 37 is an exploded perspective view of the same. Also, in the symbols used in the drawings, 9 is a stop button, 10 is a stop button, and 10 is a stop button.
12 is a playback button, 12 is a record button, 16 is a head board, 18 is a take-up reel shaft, and 43 is a lock plate. 91 is a malfunction prevention lever, 177 is a first detection lever, 1
78 is a second detection lever, 179 is a first shutter-off lever, 180 is a second shutter-off lever, 181 is a third shutter-off lever, 182 is a malfunction prevention plate, 188 is a first recess, 189 is a second recess, 192 is the detection pin, 208
, 209 is an arm, and 211 is an idler shaft.

Claims (1)

[Scope of Claims] 1 (a) ') - Rotationally biased in a predetermined direction by the rotation of the reel shaft, and the bias is released when the rotation of the reel shaft is stopped, and the first recess and the first reel are A detection member having two recessed portions. (b) A drive member that is constantly driven by a motor. (C) It is reciprocated by the driving member, and when the reel shaft is rotating, it reciprocates within the first recess with a first stroke, and when the reel shaft is stopped, it reciprocates within the second recess. A reciprocating member having a pin that reciprocates with a stroke of. (d) a lock plate actuating member that operates when the reciprocating member reciprocates in the second stroke and releases the lock plate of the playback button or the record button;
In a shut-off mechanism in a recording/playback device that is configured to release the lock of the playback button or the record button when the rotation of the reel shaft stops due to the end of the tape during playback or recording, (e) when the stop is stopped, the first (f) a head substrate that is located at a position and is slid from the first position to a second position when the playback button or the record button is operated; (f) a head substrate that is slid from the first position to the second position; a malfunction prevention lever configured to be rotated from a first position to a second position in conjunction with the sliding movement of the lever, and having a first engaging portion and a second retaining portion; When stopping, the first
The first engaging part of the malfunction prevention lever located at the position prevents the pin of the reciprocating member from moving into the second recess of the detecting member, and the second engaging part prevents the detecting member from moving into the second recess of the detecting member. A shutoff mechanism in a recording and reproducing apparatus, characterized in that the member is configured to be rotationally biased in the predetermined direction.