JPS5838846B2 - Tape recorder automatic reverse touch - Google Patents

Description

Detailed Description of the Invention This invention uses a magnetic head for one channel and two tracks, and switches its height position in two stages, and in response to the switching operation, reverses the negative state of the upper and lower coils of the magnetic head. The present invention relates to an auto-reverse device for a tape recorder, which operates a changeover switch to perform recording and playback in a 2-channel, 4-track system.

Conventionally, tape recorders that use a tape cassette in which two-channel magnetic tape is wound between a pair of reels,
The tape feed direction is constant, and when recording or playback of one channel is completed, the cassette must be turned over to start recording or playback of the other channel, and it is extremely difficult to automate this operation.

Therefore, when recording and playback of one channel is finished,
A so-called auto-reverse device has been devised that detects the end of the tape and automatically switches the tape feeding direction so that recording and playback of the other channel can be performed continuously.

However, in this case, an expensive 2-channel magnetic head must be used. In particular, a 2-channel 4-track stereo magnetic head is extremely expensive, and as a result, the tape recorder itself becomes expensive. there were.

Therefore, the present inventor used a single-channel magnetic head and changed its height position to two levels.
The idea was to enable recording and playback using the channel method.

However, with stereo 2-channel 4-track magnetic tape, the outer track is usually connected to the right speaker, and the inner track is connected to the left speaker. This caused a problem in that the negative polarity of the pair of cores of the magnetic head was reversed between the high position and the low position.

Therefore, it is possible to provide a changeover switch that reverses the polarity of the upper and lower coils of the magnetic head, and to change the above switch when changing the height position of the magnetic head. Providing a mechanism for switching and a mechanism for switching the switch would complicate the configuration, and furthermore, it would be necessary to operate both switching mechanisms at the same time, resulting in an even more complicated configuration.

This invention was made in view of these circumstances, and uses a magnetic head for one channel and two tracks.
In addition to switching the height position in two stages, a pair of left and right pinch rollers is switched toward and away from the corresponding capstan shaft, and in response to the switching operation, the polarity of the upper and lower coils of the magnetic head is reversed. The purpose of the present invention is to provide an auto-reversing device for a tape recorder having a simple structure, which operates a polarity reversal switch to perform recording and playback in a 2-channel, 4-track system.

An embodiment of the present invention will be described below with reference to the drawings.

Figure 1 shows a plan view of the tape recorder, with the board 1
Cassette loading sections 2, 2 into which a tape cassette is inserted from the front end are provided on the left and right sides of the upper front surface of a, and a pair of reel shafts 3, 3 are disposed between the loading sections 2, 2.

Further, capstan shafts 4, 4 are disposed at the front positions of the respective reel shafts 3, 3, and the capstan shafts 4, 4 and the reel shafts 3, 3 are disposed on the lower surface side of the substrate 1a. The drive board 1b is mounted on the drive board 1b.

The driving board 1b moves upward in conjunction with the loading operation of the tape cassette, and accordingly, the above-mentioned -/14 shafts 3, 3 are inserted into the tape reel of the tape cassette from below. .

A one-channel two-track magnetic head 5 is attached to the center of the upper surface of the substrate 1a via an operating plate 6.

The magnetic head 5 is vertically symmetrical with respect to the core.

Further, on both sides of the magnetic head 5, a pair of tape guides 7, 7 and pinch rollers 8, 8, each functioning as a tape tension detecting member, are arranged.

The tape guide 7.7 is movable back and forth in the front and back direction via supports 9, 9 fixed to the upper surface of the board 1a.
The pinch rollers 8, 8 are rotatably supported at respective ends of support arms 10.10 rotatably mounted on the upper surface of the substrate 1a.

Each support arm 10.10 is rotationally biased in a direction that presses a pinch roller 8,8 against a respective capstan shaft 4.4.

A motor 11 and a small gear 12 mounted on the drive board 1b are disposed at a rear position on the upper surface of the board 1a.

Further, an auxiliary board 1c is mounted parallel to the board 1a at a rear position on the upper surface of the board 1a, and an intermediate rotating body, that is, a large gear 13, is rotatably mounted on the back side of the auxiliary board 1c.

As shown in FIGS. 2 to 4, this large gear 13 has rest portions 14° 14 in which several teeth are missing at two symmetrical locations, and an annular rib 15 is provided protruding from the top surface. , its rib 15
A height cam 16 is formed on a part of the outside.

The height cam 16 has a high portion 16a at the center, and taper portions 16b, 16b inclined along the circumferential direction on both sides.

Further, a circular eccentric cam 17 is formed at the center of the upper surface.

Furthermore, locking portions 1B, 1B are provided protrudingly at two symmetrical locations on the inner surface of the lip 15.

The lower surface of the large gear 13 has an eccentric position (this engagement shaft 19
A is provided protrudingly, and a roller 19 is rotatably mounted on this shaft.

Various operating levers 20 are attached to the front end of the board 1 so as to be movable forward and backward.

FIG. 5 shows the drive mechanism attached to the drive board 1b, in which the body 21 includes a motor pulley attached to the motor shaft 22;
23. 23 is a flywheel attached to each capstan shaft 4°4, 24 is an intermediate boot IJ attached to the small gear 12, 2
Reference numerals 5 and 25 designate reel stands on which each reel shaft 3.3 is mounted via a friction mechanism.

Further, reference numeral 26 denotes an idler pulley that selectively presses against each flywheel 23, 23, and this idler pulley 26 is rotatably connected to the rotating end of a swinging lever 27 whose one end is rotatably supported on the drive board 1b. It is installed.

The central shaft 28 of the idler pulley 26 protrudes upward,
Switching booths IJ 29 and 29 are provided between the central shaft 28 and each reel stand 25° 25, respectively.

The switching boos IJ 29 , 29 are rotatably supported by one end of a switching lever 30.30 mounted on the driving board 1b at a left-right symmetrical position so as to be movable forward and backward.

This switching lever 30.degree. 30 is always urged forward.

The motor pulley 21 and the intermediate pulley 24 are rotationally connected via an endless belt 31, and the intermediate pulley 24 and one flywheel 23 are rotationally connected via an endless belt 32.

Further, the other flywheel 23 is pressed into contact with the endless belt 32 from the outside, so that both flywheels 23, 2
3, that is, both capsun shafts 4, 4 rotate simultaneously at the same speed in different directions.

FIG. 6 shows the pinch roller operating mechanism for moving the pinch rollers 8, 8 toward and away from the capstan shaft 4.4. In the figure, reference numeral 33 has a long hole 34 in the center and tape guides 7 at both ends. The detection lever 35 facing the rear end of the detection lever 35 is an interlocking lever that is located below the detection lever 33 and is attached to the upper surface of the board 1a so as to be movable forward and backward.

The detection lever 33 is rotatably supported in its elongated hole 34 and can move back and forth in the front and rear directions, and has a suppression piece 3 at the center of its front edge that presses the front end of the interlocking lever 35, as shown in FIG.
6 is cut and raised downward.

A contact piece 37 is provided protruding from the front end side of the interlocking lever 35,
The tip of the manual switching operation lever 2Qa faces this contact piece 3T.

Further, an L-shaped hole 38 is bored in the center of the interlocking lever 35.

Reference numeral 39 in the figure denotes a locking lever for controlling the rotational movement of the large gear 13, whose middle part is rotatably attached to the back side of the auxiliary board 1C, and one end of which is attached to the L-shaped hole 38 of the interlocking lever 35.
It has an engaging pin 40 that is inserted into the main gear, and a locking pin 41 that locks into the locking portion 18 of the large gear 13 at the other end.

This locking pin 41 always locks the large gear 13 at a position where one of the rest portions 14 corresponds to the small gear 12.

Furthermore, in the figure, reference numeral 42 denotes an actuation lever as a tape running direction switching mechanism for actuating the pinch rollers 8, 8, whose central portion is rotatably supported on the substrate 1a, and has a pair of left and right actuating arms 4.
3.43 is made to face the tip of the support arm 10.degree. 10 of the pinch roller from the front, so that one of the support arms can be selectively pulled away from the capstan shaft 4.

Further, a connecting arm 44 extending rearward is located on the lower surface side of the large gear 13, and a cam hole 45 provided in this arm 44 is provided.
A roller 19 attached to the lower surface of the large gear 13 is inserted into the roller 19.

So now, when the tape guide 7.7 moves backwards,
Pushed by this, the detection lever 33 and the interlocking lever 35 move in the same direction, the locking lever 39 that engages with the L-shaped hole 38 rotates in the non-biasing direction, and the locking pin 41 of the locking lever 39 comes to come off from the locking portion 18 of the large gear 13.

Then, the operating lever 42 is rotationally biased by the return force of the support arm 10 that has been separated from the capstan shaft 4, and the operating lever 42 and the large gear 13 engage with each other through the cam hole 45 and the roller 19. Therefore, the large gear 13 rotates slightly in the direction of the arrow in the figure due to the restoring force of the support arm 10, and rotates while meshing with the small gear 12, which is constantly rotating.

When the other half rotates, the other resting part 14 is disengaged from the small gear 12, and the other locking part 1
8 is locked to the locking pin 41 and held in the locked state again.

During the above operation, the operating lever 42 rotates in conjunction with the rotation of the large gear 13, and its operating arm 43.43 pulls the pinch roller 8, which is in pressure contact with the capstan shaft 4, from the capstan shaft 4. Then, the pinch roller 8 at the separated position is brought into pressure contact with the capstan shaft 4.

7 to 10 show how the magnetic head 5 is mounted. In the figures, 46 is a bracket fixed to the upper surface of the substrate 1a, and 47 is a U-shaped joint, with both sides of the joint 47 facing forward. The bottom end thereof is attached to the bracket 46 via a small screw 58 so as to be rotatable in the left and right directions.

A forward bent piece 48 is formed on the lower edge of the bottom piece of the joint 47, and a compression coil spring 49 is inserted between this bent piece 48 and the base plate 1a.
A low level adjustment screw 50 is inserted into the center of 8 from above, and the screw 50 is screwed into a screw hole drilled in the substrate 1a.

On the other hand, a magnetic head 5 is attached to the lower surface of one end of the actuating plate 6.

The operating plate 6 has both rear end edges bent downward to form a U-shape, and the U-shaped portion 6a is fitted between both sides of the joint 47.

A support shaft 51 is inserted between both sides of the joint 47, and the actuating plate 6 is rotatable in the vertical direction about the support shaft 51.

Further, one side edge of the actuating plate 6 is bent downward from a position slightly behind the magnetic head mounting portion to the rear end, and the actuating plate 6 is placed between the front end of the bent piece 52 and the substrate 1a. A tension spring 53 biased downward is tensioned.

Further, the actuating plate 6 connects the middle part of the other side edge to the large gear 13.
A screw hole is provided in the extending portion, and a machine screw 55 is screwed into the screw hole from the upper side via a compression coil spring 54.

The lower end of this machine screw 55 comes into elastic contact with the upper surface 4 of the large gear 13 due to the action of the tension spring 53, and selectively slides into contact with the height cam 16.

A pair of studs 56, 56 are provided upright on both sides of the magnetic head 5 on the upper surface of the substrate 1a.
The upper end of the upper end is screwed with height adjustment screws 57, 57.

The image adjustment screws 57, 5γ lightly contact both side edges of the front end of the actuating plate 6, prevent the actuating plate 6 from swinging in the left-right direction, and also prevent the head 57a from swinging.

The lower surface of 57a restricts the amount of upward movement of the front end of actuating plate 6.

Therefore, the actuating plate 6 operates as follows.

In other words, the machine screw 55 is connected to the height cam 1 on the top surface of the large gear 13.
When the actuating plate 6 is in contact with the symmetrical position, the actuating plate 6
That is, although the magnetic head 5 is in the low position shown in FIGS. 7 and 8, as the large gear 13 rotates, the lower end of the machine screw 55 comes into sliding contact with the upper surface of the large gear 13, and when the large gear 13 rotates half a rotation, the small screw 55 slides into contact with the upper surface of the large gear 13. The screw 55 rises along the tapered portion 16b and comes into contact with the high portion 16a of the height cam 16.

At this time, the actuating plate 6 rotates upward about the support shaft 51, and positions the magnetic head 5 at a high position as shown in FIG.

When the magnetic head 5 is in the low position, the actuating plate 6 can be rotated in the left and right height directions about the machine screw 58 by rotating the low adjustment screw 50.

In other words, when the adjusting screw 50 is tightened, the actuating plate 6 moves to the joint 47.
The adjustment screw 5 is rotated clockwise in FIG.
When 0 is heated, it rotates counterclockwise due to the return force of the spring 49.

This makes it possible to adjust the inclination of the magnetic head 5 in the horizontal and horizontal height directions.

Furthermore, when the magnetic head 5 is at a high position, the left and right height adjusting screws 57 and 57 can be tightened to adjust the degree of tightening (the inclination of the magnetic head 5 in the left and right height direction can also be adjusted).

Note that since the actuating plate 6 rotates around the support shaft 51,
The vertical movement of the magnetic head 5 is an arc movement.

However, if the radius of rotation is made sufficiently long compared to the width of rotation, that is, if the actuating plate 6 is made long, the vertical movement of the magnetic head 5 can be approximately regarded as vertical movement.
There is no problem in practical use.

However, in this embodiment, the accuracy is further improved.

That is, the magnetic head 5 is adjusted so that there is no inclination in the front-back direction when it is in a low position, and when it is rotated to a high position, the actuating plate 6 is moved between the magnetic head mounting part and the bending piece 52. The neck portion 59 is bent, thereby compensating for the longitudinal inclination of the magnetic head 5.

FIG. 11 shows the positional relationship between the magnetic head 5 and the magnetic tape 61 in the tape cassette 60.
moves up and down between the solid line position (low position) and the chain line position (high position) at (1) in the cassette 60, and the magnetic tape 61
Two tracks are recorded and played back in the lower and upper halves of the disc, respectively.

In addition, 62 in the same figure is a pad splash.

FIG. 12 shows left and right speakers SP1. This figure shows the operating part of a polarity reversal switch 63 that reverses the connection relationship between SP2 and the upper and lower coils C1, C2 (see FIG. 13) of the magnetic head 5 to switch between left and right tracks.

That is, the changeover switch 63 is arranged at the rear end of the top surface of the board 1, with its changeover knob 64 facing forward, and one end of a rotary lever 65 whose central portion is rotatably mounted on the bottom surface of the auxiliary board 1c. The switching knob 64 is held between the two.

The other end of the rotating lever 65 holds the eccentric cam 17 of the large gear 13.

Therefore, the rotary lever 65 is rotated by the rotational movement of the large gear 13.
In conjunction with this, a reciprocating rotation operation is performed, and the changeover switch 63 is operated every time the large gear 13 makes a half rotation.

As shown in FIG. 13, this selector switch 63 connects the magnetic head 5 and the left and right amplifiers AMP1. AMP2, and each amplifier AMP1. AMP2 is each speaker SP
1.

Connected to SF3.

The changeover switch 63 is connected to each amplifier AMP1. A pair of movable contacts S1. connected to AMP2. One movable contact S1 is selectively switched to fixed contacts al and bl, and the other movable contact S2 is switched to fixed contacts a2 and b2 in conjunction with each other.

The fixed contacts a and b2 are connected to one coil c1 of the magnetic head 5, and the fixed contacts a2 and bl are connected to the other coil C2 of the magnetic head 5.

Therefore, as shown in the figure, the movable contact S1 is connected to the fixed contact a.
1 and the movable contact S2 is connected to the fixed contact a2, one coil c1 of the magnetic head 5 is connected to one (left) speaker SP1 via AMPl, and the other coil c2 is connected to AMP2. to the other (right side) speaker SP2.

Then, when the switching knob 64 is switched and the movable contact S1 is connected to the fixed contact b1 and the movable contact S2 is connected to the fixed contact b2, one coil c1 of the magnetic head 5 is transferred to the other (right side) coil c1 through the AMP2. The coil c2 is connected to the speaker SP2, and the other coil c2 is connected to one (left) speaker SP1 via the AMPL.

Next, the operation of this embodiment will be explained.

First, when the tape cassette 60 is loaded into the cassette loading section 2.degree. 2, the motor 11 is connected to the power source in response to this loading operation, and the motor 11 is started.

At this time, assuming that the upper surface of the large gear 13, which is symmetrical to the height cam 16, is in contact with the machine screw 55 and the magnetic head 5 is in a low position, the operating lever 42 is rotated to the left. The right pinch roller 8 is separated from the capstan shaft 4, the left pinch roller 8 is pressed against the capstan shaft 4, and the magnetic tape 61 moves from right to left.

The left reel shaft 3 is rotated by the rotational force of the right capstan shaft that does not contribute to tape running, that is, the rotational force of the right flywheel 23, and winds the tape onto the left reel.

The magnetic head 5 is in sliding contact with the lower half of the magnetic tape 61, the changeover switch 63 is located at the position shown by the chain line in FIG. 12, and the movable contacts S1. S2 respectively fixed contacts a1゜a2
The upper coil C0 of the magnetic head 5 is connected to the left speaker SP1, and the lower coil C2 is connected to the right speaker S.
For example, a playback operation is performed by connecting to P2.

Further, a pair of tape guides T and γ enter the cassette 60 from both sides of the magnetic head 5 and come into pressure contact with the magnetic tape 61 to regulate the height position of the tape 61.

The magnetic tape 61 is placed on the feeding direction side with the magnetic head 5 as a boundary,
In other words, the tension on the left side is stronger, so the left tape guide 7 is pushed back a little, and the detection lever 33 pivoted behind it is tilted slightly to the right.

Then all the tape is wound onto the left reel,
When the right reel runs out of tape, since the end of the tape is fixed to the reel, the tension of the tape increases rapidly, and the detection lever 33 and the interlocking lever 35 move rearward due to the tape tension.

When the locking lever 39 that engages with the interlocking lever 35 rotates to release the lock on the large gear 13, the large gear 13 is moved in the direction of the capstan shaft 4 of the right pinch roller via the operating lever 42. Due to the return force, it rotates slightly ζ in the direction of the arrow in FIG. 6, and meshes with the small gear 12.

Therefore, the large gear 13 rotates by half a rotation due to the rotational force of the small gear 12, stops rotating when the next resting portion 14 corresponds to the small gear 12, and is locked again at the stop position by the locking lever 39.

While the large gear 13 rotates half a rotation, the actuating lever 42 rotates to the right to bring the right pinch roller 8 into pressure contact with the capstan shaft 4 (the left pinch roller 8
from the capstan shaft 4 (Fig. 6).

Then, in conjunction with the forward rotation of the support arm 10 that supports the right pinch roller 8, the right switching lever 30 moves forward, causing the right switching pulley 29 to switch between the right reel and the right switching pulley 29. The idler pulley 26 is inserted into a wedge shape between the stand 25 and the center shaft 28 of the idler pulley 26, and the idler pulley 26 is pressed against the left flywheel 23, so that the idler pulley 26 is connected from the left flywheel 23 to the right reel shaft 3. form a rotation transmission path to the

Further, the height cam 16 of the large gear 13 pushes up the operating plate 6 via the small screw 55, and pushes up the magnetic head 5 to a height where the operating plate 6 comes into contact with the heads 57a, 57a of the height adjustment screws 57, 57. .

Furthermore, the rotary lever 65 rotates to the right, and the changeover switch 63 is operated (as shown by the solid line in FIG. 12).

Therefore, as the large gear 13 rotates half a rotation, the magnetic head 5 moves to a high position, and the tape feeding and winding directions are switched from left to right, and the coil c1 above the magnetic head 5 acts as a movable contact. The right speaker 5P2Q is connected via S2, and the lower coil c2 is connected to the movable contact S.
1 to the left speaker SP1, and a predetermined reproduction operation is performed continuously.

As detailed above (according to this invention), a pair of capstan shafts and pinch rollers are disposed on the left and right sides of a magnetic head for one channel, two tracks, and the running direction of the magnetic tape is switched. The height position of the magnetic head is switched between two levels, and in response to the height position switching operation, a polarity reversal changeover switch is actuated to reverse the connection relationship between the left and right speakers and the upper and lower coils of the magnetic head. Since recording and playback are performed using the 2-channel 4-track system, ordinary 2-channel 4-track magnetic tape can be used without any inconvenience, and there is no need to turn over and reload the tape cassette for each channel. An auto-reverse device for a tape recorder can be provided.

In addition, an intermediate rotating body is provided that rotates in conjunction with the switching operation of the running direction of the magnetic tape, and the height position switching and switch switching of the magnetic head are performed via this common intermediate rotating body. It is possible to obtain the excellent effect that the switching of the magnetic head and the switch can be performed at the same time.

[Brief explanation of drawings]

The drawings show an embodiment of this invention. Fig. 1 is a plan view, Fig. 2 is a plan view of a large gear, Fig. 3 is a sectional view taken along line A-A in Fig. 2, and Fig. 4 is a cross-sectional view of a large gear. 5 is a plan view showing the drive mechanism 1, FIG. 6 is a plan view showing the pinch roller operating mechanism, and FIG. 7 is a side view showing the magnetic head mounting section with a portion cut away. 8 is a front view of the same, FIG. 9 is a rear view of the same, FIG. 10 is a side view of the same, FIG. 11 is a partially cutaway side view showing the positional relationship between the magnetic head and the magnetic tape, and FIG. Figure 12 is a plan view showing the actuating part of the polarity reversal switch;
The figure is an electric circuit diagram, and FIG. 14 is a partial perspective view. 4... Capstan shaft, 5... Magnetic head, 8... Pinch roller, 61...
Magnetic tape, 63...Polarity reversal switch.

Claims (1)

[Claims] 1. A one-channel, two-track magnetic head that is provided vertically movably in the width direction of the magnetic tape, a pair of capstan shafts located on the left and right sides of this magnetic head, and a corresponding capstan shaft. a pinch roller that can be pressed alternately, a pair of left and right speakers, a changeover switch for reversing the connection relationship between these two speakers and the upper and lower coils of the magnetic head, and a pinch roller that contacts the magnetic tape and adjusts the tension of the magnetic tape. a tape tension detection member that operates based on the tape tension when the tape tension increases rapidly; and the rotational force of the motor associated with the magnetic tape drive morph is obtained by the operation of this detection member to drive the pair of left and right pinch rollers, respectively. A tape recorder comprising: an intermediate rotating body that switches the magnetic head toward and away from the corresponding capstan shaft, switches the height position of the magnetic head in two stages, and switches the changeover switch. Auto reverse device.