JPH0610511Y2 - Operation mode switching mechanism of tape recorder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is a tape recorder mode in which the switching operation of the position of the head chassis in each of the reproduction, music selection, and stop modes can be performed by a single cam disk. The present invention relates to a switching mechanism.

(Prior art and its problems) Conventionally, in order to improve the feeling of operation, a so-called motor shift in which a position of a head chassis or the like is controlled by using a cam rotated by a motor and operation modes are switched A tape recorder equipped with a mechanism is well known.

However, looking at the head chassis control mechanism in the general motor shift mechanism, the playback position where the magnetic head is pressed against the tape, the stop position where the magnetic head is separated from the tape, and the magnetic head slightly touches the tape by retracting slightly from the playback position. When controlling the head chassis to a possible song selection position such as the beginning of the song on the tape, the mechanism for moving the head chassis from the stop position to the playback position and the head chassis slightly from the playback position to the song selection position Mechanisms for retracting are provided separately, and each operating mechanism requires an operating cam and its controlling plunger, which complicates the structure of the mechanism and control circuit, and also in terms of cost and space. However, it has many drawbacks such as being disadvantageous.

(Purpose of the Invention) To provide a motor shift mechanism that eliminates the drawbacks of the conventional motor shift mechanism and that can control the head chassis to play, stop, and move to the music selection position by a single cam disk. It is in.

(Outline of the Invention) A head chassis movably arranged for reproduction, stop, and music selection position, a cam board for controlling the head chassis to each of the moving positions, and the cam board for each of the moving positions of the head chassis. In the operation mode switching mechanism including a trigger lever that is locked and unlocked at a rotational position according to the above, and an electromagnet that controls the trigger lever, the trigger lever is excited by exciting the electromagnet. Each time it is operated, the cam disk is kept in a rotating state, and the head chassis is controlled so that it can be stopped, played, and sequentially moved to the music selection position, so that the mechanism is a single cam disk and the excitation time or timing of the electromagnet. It is a novel tape recorder operation mode switching mechanism capable of controlling to a desired operation mode by controlling the.

(Embodiment) FIGS. 9 to 11 are plan views of a tape recorder of the present invention, in which 1 is a chassis, 2a and 2b are reel stands, and 3a and 3b are capstans. Flywheels 4a and 4b are attached to the capstans 3a and 3b so as to rotate integrally, and are connected by a pulley 6 of a motor 5 and a belt 7 so as to rotate in mutually opposite directions. Reference numeral 8 is a regulating pulley for the belt 7.

On the chassis 1 facing the capstans 3a, 3b,
The pinch roller levers 10a and 10b, which are respectively rotatably arranged with pinch rollers 9a and 9b, have shafts 11a and 11a.
It is rotatably attached by b.

The pinch roller levers 10a and 10b are provided with springs 12 for pressing them to the capstans 3a and 3b.
a, 12b, the head chassis 14 and the tape running direction switching lever 60 described later, the capstans 3a, 3a.
Pins 101a and 101b for controlling contact and separation with b are provided.

On the chassis 1 between the reel stands 2a and 2b, a head chassis 14 to which a recording / reproducing head 13 is attached is provided with a long hole 1
4a to 14c, the pins 15a and 15b on the chassis 1 and the bearing 16b of the capstan 3b are arranged so as to be slidable forward and backward, and are always urged downward by a spring 67 as seen in the figure, and both ends thereof are Engaging portions 141a and 141b are formed to push down the pins 101a and 101b of the pinch roller levers 10a and 10b to separate them from the capstans 3a and 3b in the stopped state.

A notch 142 is formed in the central portion of the head chassis 14, and engagement protrusions 143 and 144 are cut and raised downward, and engage with an engagement portion 18a at one end of a lever 18 described later. Further, on the right side of the long hole 14a, an engagement protrusion 145 for releasing the lock of the lock lever 51 described later is formed.

Head guides 20a, 20b for guiding the movement of the erasing heads 19a, 19b are attached to both sides of the recording / reproducing head 13, and tape guides 201a, 201b are formed on the respective head guides 20a, 20b. Again 2
Reference numerals 02a and 202b are engaging portions for restricting the protrusion amount of the erasing heads 19a and 29b.

On the other hand, the erasing heads 19a and 19b have long holes 191a,
191b is rotatably attached to both ends of the lever 21, the lever 21 is rotatably attached to one end of the rotating arm 22 by a shaft 23, and the other end of the rotating arm 22 is the pinch roller lever 10a. Is rotatably arranged on the shaft 11a.

The lever 21 is provided with pins 211a and 211b for engaging the tape running direction switching lever 60, which will be described later, to operate the erasing heads 19a and 19b in a seesaw operation. Detailed operation will be described later.

FIG. 8 shows the back surface of the tape recorder. Reference numeral 30 denotes a head chassis 14, a stop position ST at which the head 13 is separated from the tape T, a recording / reproducing position RP at which the head 13 is pressed against the tape T, and a head 13. Is a head chassis control mechanism for slightly retreating from the recording / playback position to lightly contact the tape to a music selection position MS where music can be selected, and 31 is a pinch roller lever 10a, 10b and a reel stand depending on the tape running direction. It is a tape running direction switching mechanism for controlling the tape running direction switching lever 60 for switching the rotating directions of 2a and 2b and an electric circuit (not shown).

The head chassis control mechanism 30 and the tape running direction switching mechanism 31 are driven by cam disks 34 and 35 which are rotatably arranged by shafts 32 and 33, respectively. Is rotated by a drive gear 37 that is rotatably disposed. And, as is clear from FIG. 8, the drive gear 37 is the gear 3 arranged coaxially with the flywheel 4a.
8 to the gear 39 rotatably arranged on the chassis 1
a, a gear 39b that rotates integrally with the gear 39a, and a gear 40
The rotation is transmitted via a gear 40b that rotates integrally with a and the gear 40a.

The head chassis control mechanism 30 will be described with reference to FIGS. 1 to 7 showing the back surface of the chassis.

A lever 18 for moving the head chassis 14 back and forth is rotatably arranged by a shaft 17 on the rear surface of the chassis 1, and an engaging portion 18a at one end thereof is always provided between the engaging protrusions 143, 144 of the head chassis 14. The engagement pin 18b at the other end is always engaged with the first cam portion 342 of the cam board 34 described later, and the head chassis 14 can be moved back and forth by rotating the cam board 34. It is like this.

The recording control lever 4 is attached to the bearing 16b of the capstan 3b.
2 is rotatably attached, and is always biased counterclockwise by a spring 43. An engaging piece 42a that engages with the free end of the rotating arm 22 is formed at one end of the recording control lever 42. The engaging piece 42a is always connected to the rotating arm 22 by a spring 44. When the recording control lever 42 rotates counterclockwise, the rotating arm 22 is pulled up via the spring 44. Further, by setting the rotation stroke of the recording control lever 42 larger than the stroke of the rotation arm 22, the rotation arm 22 is moved upward by the spring 44 in the recording state in which the recording control lever 42 is rotated counterclockwise. Is urged to. As a result, the erasing head 19a or 19b attached to the rotating arm 22 via the lever 21 is pressed by the elasticity of the spring 44 to the engaging portion 202a or 202b of the head guide 20a or 20b.
The amount of protrusion of the erase head with respect to the tape T can be accurately determined.

Further, the recording control lever 42 has an engagement piece 42b engageable with an engagement portion 45b of an operation plate 45 described later and an engagement portion 42c engaged with an engagement step portion 51a of a lock lever 51 described later.
Are formed.

On the other hand, the bearing 16b between the recording control lever 42 and the chassis 1 includes the recording control lever 4 depending on the operation mode.
An operating plate 45 that engages with and disengages from 2 is arranged rotatably and movable left and right through a long hole 45a, and is always biased leftward by a spring 46 as viewed in the figure. An engaging portion 45b engageable with the engaging protrusion 144 of the head chassis 14 is formed at the tip portion thereof, and an engaging piece 45c engageable with the engaging protrusion 42b of the recording control lever 42 is formed. An engaging portion 45d that can be engaged with a trigger lever 47, which will be described later, is formed in the substantially central portion.

Below the recording control lever 42 and the operating plate 45 in the drawing, a trigger lever 47 for controlling the cam board 34 is rotatably arranged by a shaft 48, and the cam board 3 is provided at one end thereof.
4 third cam portion 343 and second cam portion 344 on the upper surface
An engaging pin 47a that engages with the metal plate 47b is attached to the other end of the metal plate 47b so as to be attracted to the electromagnet 50, and an operating plate 45 is provided approximately in the middle.
The engaging arms 47c that can engage with the engaging portions 45d are formed respectively, and are always biased clockwise by the spring 49.

The electromagnet 50 and the electromagnet 66, which will be described later, used in the tape recorder of the present invention are so-called release electromagnets and have a permanent magnet iron core, and the magnetic force of the permanent magnet is offset by exciting the coil. I am using a type that does. Therefore, for example, when the electromagnet 50 is excited with the metal plate 47b of the trigger lever 47 being attracted to the permanent magnet of the electromagnet 50 as shown in FIG. It is rotated clockwise by the elasticity of.

A lock lever 51 for locking the recording control lever 42 in the operating position is provided above the recording control lever 42 in each figure.
Is rotatably attached by a shaft 52 and is biased clockwise by a spring 53. The lock lever 51 is provided with an engaging portion 51a that engages with and locks the engaging portion 42c of the recording control lever 42, and an engaging protrusion 51b that can engage with the engaging protrusion 145 of the head chassis 14. ing. Incidentally, 54 is a stopper pin of the lock lever 51.

As is clear with reference to both FIG. 16 and FIG. 16, the cam disk 34 has a gear portion 341 formed on the outer periphery thereof.
Stop position ST, recording / playback position RP, music selection position M
In S, toothless portions 341a, 3 facing the drive gear 37
41b and 341c are formed.

A first cam portion 342, which is constantly engaged with the pin 18b of the lever 18, is formed on the lower surface of the cam board 34, and the head chassis 14 is stopped at the stop position ST, the recording / reproducing position RP, and the music selecting position M.
Engagement surfaces 342a, 342b, 342 for movement control to S
c are continuously formed.

The engagement surface 342a has the largest diameter, the engagement surface 342b has the smallest diameter, and the engagement surface 342c has a diameter slightly larger than that of the engagement surface 342b. Has been decided.

That is, when the pin 18b of the lever 18 is located on the engagement surface 342a having the largest diameter, the lever 18 is in the most clockwise position as shown in FIG. As shown in FIG. 9, it is at the stop position ST farthest from the tape T. Also pin 1 of lever 18
When 8b is located on the engagement surface 342b having the smallest diameter, the lever 18 is in the most counterclockwise rotation state as shown in FIG. 4, and the head chassis 14 is as shown in FIG. Then, the recording / reproducing position RP is advanced so that the head 13 is pressed against the tape T.

Further, when the pin 18b is engaged with the engagement surface 342c, the lever 18 is in a position rotated slightly clockwise as compared with when the pin 18b is engaged with the engagement surface 342b, and as shown in FIG. The head chassis 14 is slightly retracted from the recording / reproducing position RP, and becomes the so-called high-speed music selection position MS where the head 13 is lightly contacted with the tape T.

On the upper surface of the cam board 34, a third cam portion 343 and a second cam portion 344 that engage with the pin 47a of the trigger lever 47.
Are formed to face each other.

The second cam portion 344 on the outer side is for locking the positioning of the cam board 34, and is a locking projection for engaging with the pin 47a of the trigger lever 47 to stop, record and play, and lock the music disk 34 at the music selection position. 344a, 344b, 344c are formed.

The inner third cam portion 343 is for controlling the trigger lever 47, and the trigger lever 47 separated from the electromagnet 50 and unlocking the cam board 34 is rotated counterclockwise to rotate the cam portion 344. Engaging protrusions 343a to 343 for returning the engaging protrusions 344a to 344c to positions where they can be engaged.
43d is formed, and the pin 47 of the trigger lever 47 is further formed.
An engagement slope 343e for converting the pressure contact of a into the starting force of the cam disk 34 is formed.

Looking at the tape traveling direction switching mechanism 31, as shown in FIGS. 12 to 15, pinch roller levers 10a and 10b, a reel base drive system (not shown), an electric circuit and the like are provided on the rear surface of the chassis 1 in the tape traveling direction. A tape running direction switching lever 60 for switching in accordance with the above is arranged so as to be able to move laterally left and right by the long holes 60a and 60b and the shafts 61 and 33, and is always biased to the right by the spring 62 as seen in each drawing.

The pinch roller levers 10a and 10b are controlled at the lower edge of the tape running direction switching lever 60 to control the pinch rollers 9a and 9b.
Engaging slopes 601a, 601b for controlling contact and separation with the capstans 3a, 3b, and pins 211a, 2 of the lever 21.
11b to engage the erasing heads 19a and 19b with the tape T
Engaging slopes 602a and 602b for contacting with and separating from each other are formed.

Therefore, as shown in FIG. 13, when the tape running direction switching lever 60 is moved to the right, the forward side pinch roller lever 10a comes off the engaging slope 601a and presses the pinch roller 9a to the capstan 3a. The reverse side pinch roller lever 10b is pushed down by the engagement slope 601b to separate the pinch roller 9b from the capstan 3b. As for the erasing head, the engaging pin 2
11b is pushed down by the engagement slope 602b, and the engagement pin 211a is removed from the engagement slope 602a, whereby the lever 21 is rotated counterclockwise, the forward side erasing head 19a is pressed against the tape T, and reverse. The side erasing head 19b is separated from the tape T. As a result, the tape forward running state is set.

Further, the tape reverse running state can be performed in exactly the same manner by moving the tape running way switching lever 60 to the left as viewed in the figure, contrary to the above.

In the stopped state shown in FIG. 12, the pinch roller levers 10a and 10b on the left and right are clearly arranged on the engaging portion 141 of the head chassis 14 with reference to FIG.
a, 141b are separated from the capstans 3a, 3b, and the erasing heads 19a, 19b are also retracted from the tape T and have nothing to do with the tape running direction switching lever 60. As the chassis 14 and the lever 21 move forward, they can be controlled by the tape running direction switching lever 60. Details will be described later.

On the other hand, a pin 603 is provided on the tape running direction switching lever 60.
Is provided, the pin 603 is engaged in the cam portion 352 on the lower surface of the cam disc 35 for switching the tape traveling direction, and the rotation of the cam disc 35 causes the tape traveling direction switching lever 60 to move laterally. There is.

A gear portion 351 that can mesh with the drive gear 37 is formed on the outer periphery of the cam disk 35, and the gear portion 351 has toothless portions 351a and 351b facing the drive gear 37 in the forward traveling state and the reverse traveling state. Has been formed.
A cam portion 352 including a large diameter portion 352a for moving the tape running direction switching lever 60 with its pin 603 to the right position (forward) and a small diameter portion 352b for moving it to the left position (reverse) is formed on the lower surface. There is.
Further, a cam portion 353 is formed on the upper surface for engaging with a trigger lever 63, which will be described later, to lock the rotational position.
The cams 35 are locked to the forward positions of the cams 35,
Locking portions 353a, 35 for locking in the reverse position
3b is formed away, and the outer periphery has an engagement slope 35 for converting the pressure contact force of the trigger lever 63 into the rotational force of the cam disk 35.
4a, 354b, small diameter portion 354 for returning the trigger lever 63
A cam portion 354 that forms c is formed.

The trigger lever 63 is rotatably attached to the chassis 1 by a shaft 64 and is biased counterclockwise by a spring 65, and has a cam portion 353 of the cam board 35 at one end.
Is provided with an engaging pin 63a, and the other end is provided with a metal plate 63b. A release-type electromagnet 66 that attracts and holds the trigger lever 63 against the spring 65 is arranged on the chassis 1 facing the metal plate 63b.

Next, the operation will be described step by step.

(1) Stopped state As shown in FIG. 1, the cam disk 34 has a toothless portion 341a.
Is opposed to the drive gear 37, and the locking projection 344a of the second cam portion 344 on the upper surface is locked by the pin 47a of the trigger lever 47 to maintain that position. The position of the trigger lever 47 rotated counterclockwise against the spring 49 is held by being attracted to the permanent magnet of the electromagnet 50.

The pin 18b of the lever 18 for controlling the head chassis is in a position where the maximum diameter portion 342a of the first cam portion 342 is engaged, and the lever 18 is rotated clockwise by the spring 67 of the head chassis 14. The head chassis 14 is retracted to a stop position ST where the head 13 is separated from the tape T, as shown in FIG.

The left and right pinch roller levers 10a and 10b are engaged with the engaging portions 141a and 141b of the head chassis 14, respectively.
It is pushed down by and is forcibly separated from the capstans 3a and 3b.

The recording control lever 42 is rotated counterclockwise by a spring 43, and the rotation arm 22 is also in a position where the lever 21 is retracted downward as viewed in the figure, and the erasing heads 19a and 19b at both ends of the lever 21 are Both are in the stop position ST separated from the tape T.

Further, the trigger lever 47 rotates counterclockwise and its arm portion 47c moves leftward as viewed in FIG. 1, whereby the operating plate 45 is moved leftward by the spring 46, and its engagement The portion 45b is in a position where it does not engage with the engagement protrusion 144 of the head chassis 14.

The lock lever 51 is held by a stopper pin 54 at a position where it is rotated clockwise by a spring 53.

(2) Play state In the stop state described above, the electromagnet 50 is instantly excited only once.

The holding force of the permanent magnet is canceled by the excitation of the electromagnet, and the trigger lever 47 moves the spring 49 as shown in FIG.
Is rotated clockwise by.

As a result, the pin 47a of the trigger lever 47 is attached to the cam board 3
4 is separated from the locking projection 344a of the second cam portion 344, and the locked state of the cam board 34 is released. At the same time, the pin 47a of the trigger lever 47 is connected to the inner third cam portion 3
The cam disc 34 is pressed against the engagement slope 343e of the shaft 43, receives the rotational activation force in the clockwise direction, meshes with the drive gear 37, and is thereafter rotated by the drive gear 37.

When the cam disk 34 rotates counterclockwise, the lever 18 is rotated counterclockwise by moving the pin 18b thereof to the large diameter portion 342a of the first cam portion 342 or gradually to the small diameter portion 342b. The head chassis 14 is moved upward by the engaging portion 18a as viewed in the figure, that is, in the direction of advancing toward the tape T.

On the other hand, when the cam board 34 is rotated to the position shown in FIG. 3, the pin 47a of the trigger lever 47 is pressed outward by the engaging projection 343a of the third cam portion 343, so that the trigger lever 47 springs 49. Counterclockwise, the position is held again by the permanent magnet of the electromagnet 50 (at this time, the electromagnet 50 is in the non-excited state).

In the above-mentioned operation, when the trigger lever 47 is rotated clockwise, the engagement plate 47c moves the actuation plate 45 to the right against the spring 46, and the engagement portion 45 is temporarily moved.
b is brought to a position facing the engagement protrusion 144 of the head chassis 14, but the trigger lever 47 is rotated counterclockwise by the engagement protrusion 343a of the third cam portion 343 to return again. When the head chassis 14 moves forward, the engaging portion 4 is moved by the elasticity of the spring 46 to the left.
5b is controlled so as not to engage with the engagement protrusion 144 of the head chassis 14. That is, the operating plate 45 does not operate even when the head chassis 14 moves forward, and the erasing heads 19a, 1
The rotating arm 22 that controls 9b does not move from the stop position.

After that, the cam disk 34 continues to rotate, and the pin 18b of the lever 18 moves the small diameter portion 34 of the first cam portion 342 as shown in FIG.
When the head chassis 14 is moved to 2b, as shown in FIG. 10, the head chassis 14 comes to the recording / reproducing position RP where the head 13 is pressed against the tape T.

As the head chassis 14 moves forward, the pinch roller levers 10a and 10b become free, and the engaging traveling slopes 601a and 601b of the tape traveling direction switching lever 60 can be switched to the side corresponding to the tape traveling direction.

On the other hand, as shown in FIG.
1b is in the opposite position, the rotation transmission to the cam disc 34 is cut off, and at the same time, the pin 47a of the trigger lever 47 engages with the locking portion 344b of the second cam portion 344 to cause the cam disc 3 to move.
Position 4 is locked.

It should be noted that the first cam portion 3 in pressure contact with the pin 18b of the lever 18
An inclined surface is formed on the small diameter portion 342b of 42, and the pressing force of the pin 18b of the lever 18 acts as a starting force for rotating the cam disk 34 clockwise.

(3) Recording State The recording operation is performed by exciting the electromagnet 50 similarly to the play operation, but the play operation and the recording operation can be selected by the excitation timing of the electromagnet.

The operation of the head chassis 14 is exactly the same as that of the play operation. By exciting the electromagnet 50, the cam disk 34 is unlocked and engaged with the drive gear 37. Thereafter, the head disk 14 is moved forward by the rotation of the cam disk 34. However, during the recording operation, as shown in FIG. 3, the cam board 34 is moved to the position where the trigger lever 47 is rotated counterclockwise by the engaging projection 343a of the third cam portion 343. When it is rotated, the electromagnet 50 is excited again (it may remain excited after the start of the cam disk 34). Then, the trigger lever 47 is returned to the position where it was once attracted to the electromagnet 50 by the engaging protrusion 343a, but since the electromagnet is excited, the engaging protrusion 34 as shown in FIG.
When 3a is removed, it is rotated clockwise by the spring 49 again.

By rotating the trigger lever 47, the engaging arm 4
7c presses the engaging portion 45d of the operating plate 45 to the right, and the operating plate 45 is moved to the right against the spring 46. Then, the engaging portion 45b of the actuating plate 45 is at a position where it can be engaged with the engaging protrusion 144 of the head chassis 14. The operating plate 45
Even if the key moves to the right, the engaging piece 45c is in a position where it can be engaged with the engaging protrusion 42b of the recording control lever 42.

Therefore, when the cam plate 34 continues to rotate clockwise and the head chassis 14 moves forward by the lever 18, the engagement protrusions 144 of the head chassis 14 cause the actuation plate 45 to rotate clockwise, and the engagement piece 45c is used. The engagement protrusion 42b of the recording control lever 42 is pressed, and this is rotated clockwise.

The recording control lever 42 is rotated by the spring 44 to rotate the arm 22.
Since the recording control lever 42 is rotated, the rotating arm 22 is rotated counterclockwise as viewed in the figure, and the lever 21 is moved forward to the tape T, depending on the tape running direction. Side erasing head (forward side erasing head 19a in the figure) advances according to the head guide 20a on the head chassis 14 and is pressed against the tape T to form a tenth portion.
The recording state shown in the figure is reached. Further, since the rotation stroke of the recording control lever 42 is set to be larger than the rotation stroke of the rotating arm 22, the recording control lever 42 separates the engaging portion 42a from the rotating arm 22 in the recording state to rotate it. The moving arm 22 is biased upward by a spring 44 as viewed in the figure. As a result, the erasing head 19a advances to the tape T along with the head guide 20a on the head chassis 14, and the engaging portion 202a of the head guide 20a.
The tape 44 is pressed against the tape T by the elastic force of the spring 44 and positioned with respect to the tape T.

When the cam disk 34 continues to rotate and the head chassis 14 is brought to the recording / reproducing position, as shown in FIG. 6, the cam disk 34 has the toothless portion 341b in the drive gear 37 as in the play operation. Stop while facing each other. Also the trigger lever 4
7 is rotated counterclockwise by the engagement protrusion 343b of the third cam portion 343 immediately before the cam board 34 reaches the recording / reproducing position. At this time, the electromagnet 50 is already in a non-excited state, and the trigger lever 47 is held at its rotating position by the permanent magnet of the electromagnet 50, and the pin 47a thereof is held.
Becomes a position facing the locking protrusion 344b of the second cam portion 344. Therefore, the cam disc 34 is held at its rotational position in exactly the same manner as during the play operation.

The recording control lever 42 is locked at its rotation position by the engagement portion 42c of the recording control lever 42 engaging with the engagement portion 51a of the lock lever 51, so that the rotation arm 22 or the tape T of the erasing head 19a or 19b is locked. The pressed forward position is locked and the recording state is maintained.

The lock lever 51 is pressed by the engagement protrusion 145 on the side surface of the head chassis while the head chassis 14 is moving forward,
Although the head chassis 14 is once rotated counterclockwise, when the head chassis 14 is advanced to the recording / reproducing position, it is brought to the position rotated clockwise by the spring 53 again, and the recording control lever 42 is surely moved. Locked.

(4) Reversing operation of tape running direction In the above recording and reproducing states, the tape running direction can be reversed by exciting the electromagnet 66.

FIG. 13 shows a tape forward recording state. The cam disk 35 is in a position where its toothless portion 351a faces the drive gear 37, and the locking portion 353a of the cam portion 353 is engaged with the pin 63a of the trigger lever 63. The position is held by being stopped.

The tape running direction switching lever 60 has its pin 603 located at the large diameter portion 352a of the cam portion 352, and is in the state of being moved to the right as viewed in the figure. Therefore, the reverse side pinch roller 9b and the erasing head 19b are retracted from the tape T by the engaging slopes 601b and 602b, respectively, and the forward side pinch roller 9a and the erasing head 19a are pressed against the capstan 3a and the tape T, respectively. It is in the forward recording state. Needless to say, the reel drive system, electric circuit and the like (not shown) are also switched to the forward running side by the tape running direction switching lever 60.

When the electromagnet 66 is excited in this state, as shown in FIG. 14, the trigger lever 63 is rotated counterclockwise by the spring 65, and its engaging pin 63a is pressed against the locking portion 354a of the cam portion 353. It As a result, a clockwise rotation starting force is applied to the cam board 35, and the cam board 35 is brought into mesh with the drive gear 37 as shown in FIG.

When the cam board 35 rotates, the tape running direction switching lever 6
0 indicates that the pin 603 has a large diameter portion 352a of the cam portion 352.
To the small diameter portion 352b, and moves leftward against the spring 62. As a result, the forward side pinch roller 9a and the erasing head 19a are respectively engaged with the engaging slope 60.
The reverse side pinch roller 9b and the erasing head 19b are pressed against the capstan 3b and the tape T by the tapes 1a and 602a, and at the same time, the reel base drive system and the electric circuit (not shown) are switched, and the reverse recording state is set. Become.

The cam disk 35 is at a position where the toothless portion 351b faces the drive gear 37. Immediately before that, the pin 63a of the trigger lever 63 is returned to be rotated clockwise by the small diameter portion 354c of the cam portion 354, and is held by the electromagnet 66 again, and the cam board 35 is engaged with the cam portion 353. The position of the stopper 353b is maintained by being locked by the engagement pin 63a of the trigger lever 63.

After that, the electromagnet 66 is momentarily excited to rotate the trigger lever 63, thereby rotating the cam board 35 and reversing the tape running direction.

(5) Music selection operation A music selection state can be obtained by exciting the electromagnet 50 in the recording or playing state.

For example, when the electromagnet 50 is excited in the recording state shown in FIGS. 6 and 10, the trigger lever 47 is rotated clockwise by the spring 49, and the engagement pin 47a thereof is separated from the locking portion 344b of the cam portion 344. Then, the lock of the cam board 34 is released.

The cam board 34 is rotated clockwise by the pressure contact force between the inclined surface of the small diameter portion 342b of the first cam portion 342 and 18b of the lever 18, and is in mesh with the drive gear 37.

The cam disk 34 is rotated to a position where the toothless portion 341c faces the drive gear 37, and the pin 18b of the lever 18 moves to the music selection position 342c where the diameter is slightly larger than the small diameter portion 342b of the first cam portion 342. . At this time, trigger lever 4
7 rotates counterclockwise when its pin 47a is pressed by 343c of the third cam portion 343, and the electromagnet 5
7, the cam disk 34 is held at this position by the locking portion 344c of the cam portion 344 being locked by the pin 47a of the trigger lever 47, as shown in FIG. ing.

This causes lever 18 to rotate slightly clockwise,
As shown in FIG. 11, the head chassis 14 has a tape T
The head 13 is moved back to the music selection position where the head 13 is lightly touched.
When the head chassis 14 is retracted, the pinch roller 9a is separated from the capstan 3a by the engaging portion 141a, and the engaging portion 51b of the lock lever 51 is pushed leftward by the engaging portion 145 of the head chassis 14. Is rotated counterclockwise by the recording control lever 42.
Is unlocked.

Therefore, the recording control lever 42 is returned counterclockwise by the spring 43, and the rotary arm 22 is also returned to the stop position retracted from the tape T. The operating plate 45 is also moved to the left by the elastic force of the spring 46, and the engaging portion 45b of the operating plate 45 is returned to the original position where it does not face the protrusion 144 of the head chassis 14.

By the above operation, the recording state is released, the tape recorder becomes a state in which music can be selected as shown in FIGS. 7 and 11, and the reel base drive system (not shown) is set to the high speed transfer mode,
By detecting a non-recording portion on the tape T by a well-known inter-track detecting circuit, it is possible to find the beginning of the music recorded on the tape.

The tuned position 342c of the first cam portion 342 is also formed with an inclined surface for converting the pressure contact force of the pin 18b of the lever 18 into a rotational force in the clockwise direction, so that the cam disk 34 is biased clockwise. It is held in a closed state.

In the above-described music selection state, when a music interval on the tape T is found, or when the music selection operation is stopped, the electromagnet 50 is excited to rotate the trigger lever 47 clockwise.
The lock of the cam board 34 is released.

The cam disk 34 is meshed with the drive gear 37 by the pressure contact force of the pin 18b of the lever 18, and when the toothless portion 341a is rotated to the position facing the drive gear 37, the engagement protrusion 343d of the third cam portion 343 is used. The locking portion 344a of the second cam portion 344 is locked by the pin 47a of the trigger lever 47 that has been returned to the outside, and then the pin 47a returns to the stopped state of FIG.

If the electromagnet 50 is excited again (or the electromagnet 5
If 0 is left excited, the play state can be established as described above, and the play state can be established following the music selection operation.

It should be noted that when the operation is shifted from the play state to the music selection operation, the operation for canceling the recording is not necessary and the operation is exactly the same as the above-mentioned operation, and therefore the description thereof will be omitted.

As described above, the operation mode switching mechanism of the present invention can control four operation modes of recording, reproduction, song selection, and stop by one cam board 34, and the cam board 34 can be located at a position corresponding to each mode. Whether or not to stop is controlled by the excitation timing or the excitation time of the electromagnet 50. Therefore, when the cam board 34 moves from the recording or playback position to the music selection position, the electromagnet 50 is excited or the previous operation mode is released. If the excitation state is maintained from that time, the rotation of the cam board 34 can be controlled to the stop position without stopping. Further, if the cam disk 34 is rotated from the stopped state and the electromagnet 50 is excited or excited when the cam disk 34 reaches the recording / reproducing position, the next music selection state can be directly established, and the excitation timing of the electromagnet 50 or By controlling the excitation time, switching patterns of all operation modes are possible.

(Effects of the Invention) As described above, according to the operation mode switching mechanism of the present invention, the head chassis movably arranged to play, stop, and select music positions, and the head chassis is controlled to the respective moving positions. Cam disk, a trigger lever that locks the cam disk in a rotational position corresponding to each of the moving positions of the head chassis and releases the locking, and an electromagnet that controls the trigger lever. In the operation mode switching mechanism consisting of, the cam disk is made to rotate every time the trigger lever is operated by exciting the electromagnet, the head chassis is stopped, and the reproduction and music selection positions can be sequentially controlled. With a single cam board and control plunger, the head chassis can be stopped, played, and controlled to multiple operating positions for song selection, greatly simplifying the control mechanism and reducing costs. It is also advantageous in terms of space, and it is also possible to skip the intermediate operation mode and directly control to the desired operation mode simply by controlling the excitation time or timing of the electromagnet, which simplifies the control circuit and improves operability. Is also effective.

[Brief description of drawings]

Each drawing shows an embodiment of the present invention, and is shown in FIG.
FIG. 7 is a plan view of the head chassis control mechanism as seen from the back side. FIG. 1 is a stopped state, FIGS. 2 and 3 are states in the middle of transition from the stopped state to a recording or playback state, and FIG. Is a play state, FIG. 5 is a state showing the moment when the recording operation is started, FIG. 6 is a recording state, and FIG. 7 is a music selection state. FIG. 8 is a plan view showing the structure of the back surface of the tape recorder. 9 to 11 are plan views seen from the front side of the tape recorder. FIG. 9 shows a stopped state, FIG. 10 shows a forward recording state, and FIG. 11 shows a music selection state. First
2 to 15 are plan views seen from the back side of the tape running direction switching mechanism. FIG. 12 shows a stopped state (the tape running direction is the forward side), FIG. 13 shows a forward recording state, and FIG.
The figures respectively show states in the middle of switching the tape running direction from the forward direction to the reverse direction. FIG. 16 is a plan view of the cam board 34. Explanation of symbols 1 ... Chassis, 3a, 3b ... Capstan 10a, 10b ... Pinch roller lever 14 ... Head chassis, 143-145 ... Engagement protrusion 18 ... Lever, 19a, 19b ... Erase head 21 ...... Lever, 22 …… Rotating arm 30 …… Head chassis control mechanism 31 …… Tape running direction control mechanism, 34,35 …… Cam board 37 …… Drive gear, 42 …… Recording control lever 45 …… Operating plate , 47, 63 …… Trigger lever 50, 66 …… Electromagnet, 51 …… Lock lever 60 …… Tape running direction switching lever

Claims (1)

[Scope of utility model registration request] 1. A magnetic head provided with a stop position, a reproduction position where the magnetic head is pressed against the tape, and a music selection position where the magnetic head is slightly retracted to bring the magnetic head into light contact with the tape. A head chassis that is freely arranged, a drive gear that is driven by a motor, a cam disc that is rotated by the drive gear to control the movement of the head chassis to each of the moving positions, and the cam disc that is the head chassis of the head chassis. In an operation mode switching mechanism including a trigger lever that locks at a rotation position corresponding to each moving position and an electromagnet that controls the trigger lever, the cam disk has a plurality of toothless portions facing the drive gear. A first gear for bringing the head chassis to a stop position, a reproduction position, a music selection position, and a stop position in this order as the gear part and the cam disk rotate. Second for engaging with the cam portion, said trigger lever engaging with said cam plate to said respective rotational position
A cam portion and a third cam portion for guiding the trigger lever from a lock releasing position separated from the second cam portion to a lockable locking position, and the electromagnet Is magnetized at all times and is non-magnetized when energized. When the electromagnet is magnetized, the trigger lever is attracted so that the head chassis can be moved through the second cam portion of the cam board. A tape recorder characterized in that the operation mode is switched by permitting rotation of the cam disk by releasing the attraction of the trigger lever when the electromagnet is not magnetized by energization while being locked in position. Operation mode switching mechanism.