JPS596537Y2 - Tape recorder auto-reverse device - Google Patents

Description

[Detailed explanation of the invention] This invention has a pair of capstan shafts and a Vinci roller on each side of the magnetic head, and uses the rotational force of the Capstan shaft on the side where the Vinci rollers are separated from each other to take up the tape. The present invention relates to an auto-reverse device for a tape recorder which rotates the reel shaft of the tape recorder.

For example, in a tape recorder that uses a tape cassette with a two-channel magnetic head wound between one pair of reels, the tape feed direction is constant, and the cassette is turned over when recording or playback of one channel is completed. The other channel must be recorded or played back, and it is extremely difficult to automate this operation.

Therefore, a pair of capstan shafts and Vinci rollers are arranged on the left and right sides of the magnetic head, and each Vinci roller is alternately pressed against the capstan shaft. A so-called auto-reverse device is considered, which 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.

On the other hand, the tape is held in pressure between a capstan shaft and a vinyl roller, and is sent in a fixed direction by the rotational force of the capstan shaft, but in order to wind the tape, it is necessary to rotate the reel shaft on the tape running side. .

Therefore, the reel shaft is usually driven to rotate by the rotational force of the capstan shaft.

However, with such a structure, the load on the capstan shaft increases, which causes wow and flutter.

This idea was devised in view of these circumstances. A pair of capstan shafts and vinci rollers are placed on each side of the magnetic head, and the running direction of the magnetic tape is switched to enable recording and playback using a multi-channel system. This eliminates the trouble of turning over and reloading the tape cassette every time one channel is completed, and also rotates the reel shaft on the tape winding side using the rotational force of the capstan shaft on the side where the vinyl roller is separated. The load on the capstan shaft that drives and feeds the tape is reduced, thereby preventing the occurrence of wow and flutter, and the switching operation of the left and right Vinci rollers and the power transmission switching operation between the left and right reel shafts. and an auto-reversing device for a tape recorder that can set the timing relationship of the vertical movement of the magnetic head with high precision, and that can perform switching operations with the same reliability no matter which direction the tape is running. This is what I am trying to do.

An embodiment of this 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.

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

The driving board 1b moves upward in conjunction with the loading operation of the tape cassette, and along with this, the reel shaft 3,
3 is inserted into the tape reel of the tape cassette from below.

A 1-channel, 2-track magnetic head 5 is mounted at 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 tension detection chips 7, 7 and a pair of vinyl rollers 8, 8 are arranged.

The tape tension detection chips 7, 1 are movable back and forth in the front and rear directions via supports 9, 9 fixed on the upper surface of the substrate 1a, and the Vinci rollers 8, 8 are rotatable on the upper surface of the substrate 1a. Mounted support arm 10. It is rotatably supported at each tip of 10.

Each support arm 10. 10 is rotationally biased in a direction that presses the Vinci rollers 8, 8 against the respective capstan shafts 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 IC 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 this auxiliary board IC.

As shown in FIGS. 2 to 4, this large gear 13 has a resting portion 14 with several teeth missing at two symmetrical locations. 14
It has an annular rib 15 protruding from its upper surface, and the rib 1
A height cam 16 is formed on a part of the outside of 5.

This height cam 16 has a high part 16a at the center, and tapered parts 16b, 16b inclined along the circumferential direction on both sides.
It is said that

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

Furthermore, locking portions 18 are provided at two symmetrical locations on the inner surface of the rib 15. 18 are installed protrudingly.

A retaining shaft 19a is provided at an eccentric position on the lower surface of the large gear 13.
is provided protrudingly, and a roller 1g 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 mounted on the drive board 1b, in which reference numeral 21 denotes 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 pulley attached to small gear 12;
5 and 25 are reel stands on which the respective reel shafts 3 and 3 are mounted via friction mechanisms.

26 is each flywheel 23. The idler pulley 26 selectively presses against the swing lever 27, which has one end rotatably supported on the drive board 1b.
It is rotatably attached to the rotating end of.

The central shaft 2B of the idler pulley 26 protrudes upward,
Switching pulleys IJ 29, 29 are provided between the central shaft 2B and each reel stand 25, 25, respectively.

The switching pulleys IJ29, 29 are switching levers 30 mounted at symmetrical positions on the drive board 1b so as to be movable forward and backward.
, 30 is rotatably supported.

The switching levers 3G, 30 are always biased 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 against the endless belt 32 from the outside, so that both flywheels 23,
23, that is, both capstan shafts 4, 4 rotate simultaneously at equal speeds in different directions.

FIG. 6 shows a switching mechanism for moving the vinyl rollers 8, 8 toward and away from the capstan shafts 4, 4. In the figure, reference numeral 33 has a long hole 34 in the center, and a tape tension detection chip 1 at both ends. , 7 is an interlocking lever located below the detection lever 33 and mounted on 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 forward and backward in the front and rear directions, and a pressing piece 36 that presses the front end of the interlocking lever 35 is cut downward and shaped at the center of the front edge. It has been pierced.

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 20a faces this contact piece 37.

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

Reference numeral 39 in the figure denotes a locking lever for controlling the rotation of the large gear 13, whose middle part is rotatably attached to the back side of the auxiliary board 1C, and whose one end is inserted into the elongated hole 34 of the interlocking lever 35. It has a locking pin 40 that locks on 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 parts 14 corresponds to the small gear 12.

The detection lever 33, interlocking lever 35, and locking lever 39 constitute a trigger lock mechanism.

As will be described later, in this first rigger lock mechanism, the tape tension detection chips 7, 7 are pressed against the running magnetic tape, and when the tension of the magnetic tape is suddenly increased at the end of the tape, the tension is transferred to the two detection chips 7. , 7 to release the holding state from the large gear 13.

Further, reference numeral 42 in the figure is an operating lever for operating the pinch rollers 8, 8, whose center portion is rotatably supported on the base plate 1a, and a pair of left and right operating arms 43, 43 are connected to the support arms 10, 10 of the pinch rollers. The tips of the support arms are opposed from the front, and one of the support arms is 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.

Now, when the tape tension detection chips 7, 7 move backward, they push the detection lever 33 and the interlocking lever 3.
5 moves in the same direction, the locking lever 39 that engages with the L-shaped hole 3B rotates in the non-biasing direction, and the locking pin 41 of the locking lever 39 comes off from the locking portion 1B of the large gear 13. It becomes like this.

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 return 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 by the locking pin 41 and held in a stopped state again.

During the above operation, the operating lever 42 rotates in conjunction with the rotation of the large gear 13, and its operating arms 43, 43 pull the Vinci roller 8, which is in pressure contact with the capstan shaft 4, from the capstan shaft 4. Then, the vinyl roller 8 at the separated position is brought into pressure contact with the capstan shaft 4.

Figures 7 to 10 show the mounting part of the magnetic head 5, and in the figures, 46 is a bracket fixed to the upper surface of the board 1a, and 47 is a U-shaped joint, with both sides of the joint 47 facing forward. , and one end of the bottom is attached to the bracket 47 via a pin 58 so as to be rotatable in the left-right direction.

A forward bent piece 4B 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 4B and the base plate 1a.
A low adjustment screw 5G is inserted into the center of 8 from above, and the screw 50 is screwed into a screw hole drilled in the board 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 small screw 55 is screwed into the screw hole from the upper surface side via a compression coil spring 54.

The lower end of this machine screw 55 is elastically abutted against the upper surface of the large gear 13 by the action of the tension spring 53, and the height cam 1
selectively slides into contact with 6.

A pair of studs 56. are provided on both sides of the magnetic head 5 on the upper surface of the substrate 1a. 56 are erected, and each stud 56,
At the upper end of 56 is a height adjustment screw 57. 57 are screwed together.

Both adjusting screws 57. 57 lightly contacts both side edges of the front end of the actuating plate 6 to prevent the actuating plate 6 from swinging in the left-right direction, and also controls the amount of upward movement of the front end of the actuating plate 6 with the lower surface of the heads 57a, 57a. I'm trying to regulate it.

Therefore, the actuating plate 6 operates as follows.

That is, the machine screw 55 is connected to the height cam 16 of the top surface of the large gear 13.
When the actuating plate 6, that is, the magnetic head 5 is in a low position as shown in FIGS. 7 and 8, the machine screw 55 lowers its lower end as the large gear 13 rotates When the machine screw 55 comes into sliding contact with the upper surface of the large gear 13 and rotates half a turn, the machine screw 55 rises along the tapered part 16b and comes into contact with the high part 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 a low position, the operating plate 16 is adjusted by rotating the low adjustment screw 50.
It can be rotated horizontally and vertically around the center.

That is, 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 loosened, the return force of the spring 49 causes it to rotate counterclockwise.

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

When the magnetic head 5 is in the high position, the left and right height adjustment screws 57. By adjusting the tightness of the magnetic head 57, the inclination of the magnetic head 5 in the left and right height direction can 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-rear direction when it is in a low position, and when it is rotated to a high position, the actuating plate 6 moves into the so-called neck part between the magnetic head mounting part and the bending piece 52. 59, thereby compensating for the inclination of the magnetic head 5 in the longitudinal direction.

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) within the cassette 60, and records and plays two tracks on the lower and upper halves of the magnetic tape 61, respectively. ing.

Note that 62 in the figure is a pad spring.

FIG. 12 shows the operating portion of the polarity reversal switch 63 for switching between the left and right tracks of the magnetic head 5. In FIG.

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 underside of the auxiliary board IC. The switching knob 64 is held between the two.

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

Therefore, the rotary lever 65 rotates back and forth in conjunction with the rotation of the large gear 13, and ? The changeover switch 63 is operated every time the gear 13 makes a half turn.

As shown in FIG. 13, this changeover switch 63 is interposed between the magnetic head 5 and the left and right amplifiers AMP1, AMP2, and each amplifier AMP1
, AMP2 are connected to speakers SP1 and SP2, respectively.

The changeover switch 63 has a pair of movable contacts S1, S2 connected to each amplifier AMP1, AMP2, one movable contact S1 connects to fixed contacts a1, b1, and the other movable contact S2 connects to fixed contacts a2, b2 selectively and 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 b1 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 SPE via AMP1, and the other coil C2 is Connect to the other (right side) speaker SP2 via AMP2.

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 C of the magnetic head 5 is connected to the other (right side) speaker via the AMP2. SP2, and the other coil C2 is connected to one (left) speaker SP1 via AMP1.

Next, the operation of this embodiment will be explained.

First, when the tape cassette 60 is loaded into the cassette loading section 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 Vinci roller 8 is separated from the capstan shaft 4, the left Vinci 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.

Further, 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 indicated by the chain line in FIG. 12, and connects the movable contacts S1 and S2 to the fixed contacts a1 and a2, respectively, so that the upper coil C1 of the magnetic head 5 is connected to the left speaker SP1, and the lower coil is connected to the left speaker SP1. C2 is the right speaker SP
2, for example, a playback operation is performed.

Further, a pair of tape guides 7, 7 enters into the cassette 68 from both sides of the magnetic head 5, presses against the magnetic tape 61, and regulates 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 strong, 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.

Then, when the locking lever 39 that engages with the interlocking lever 35 rotates and releases the lock on the large gear 13, the large gear 13 is actuated. Due to the return force, it rotates slightly 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 press the right Vinch roller 8 against the capstan shaft 4 while also pressing the left Vinch roller 8 onto the capstan shaft 4. (Figure 6).

Then, the right switching lever 30 moves forward in conjunction with the forward rotation of the support arm 10 that supports the right Vinci roller 8, and the right switching pulley 29 switches 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.

Further, the height cam 16 of the large gear 13 pushes up the operating plate 6 via the machine screw 55, and the magnetic head 5 is raised to the height where the operating plate 6 abuts the heads 57a, 57a of the height adjusting screws 57, 57. Push it up.

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 direction switches from left to right, and the coil C1 above the magnetic head 5 moves. The lower coil C2 connects to the right speaker SP2 via the contact S2, and the lower coil C2 connects to the movable contact S.
1 to the left speaker SPI, and a predetermined reproduction operation is performed continuously.

As detailed above, according to this invention, a pair of capstan shafts and a Vinci roller are arranged on each side of the magnetic head, and the running direction of the magnetic tape is switched to perform recording and playback in a multi-channel system. In this way, the trouble of turning over and reloading the tape cassette every time one channel is completed is eliminated, and the reel shaft on the tape winding side is rotationally driven by the rotational force of the capstan shaft on the side where the vinyl roller is separated. This reduces the load on the capstan shaft on the tape feeding side, thereby preventing the occurrence of wow and flutter.

In addition, the magnetic head is moved up and down in the tape width direction using a motor that drives the capsun shaft and reel shaft.
By making the switching operation of the Vinci roller and the intervention of the switching pulley between the capstan shaft and the reel shaft, it is possible to simplify the setup and reduce the star-falling motion of the magnetic head. The switching operation of the vinch roller and the intervening operation of the switching pulley between the capstan shaft and the reel shaft can be performed at optimal timing.

Furthermore, by arranging tape tension detection chips on both sides of the magnetic head, an auto-reversing device for a tape recorder is provided, which has the effect of ensuring uniform and reliable operation no matter which direction the magnetic tape runs. It is something that can be done.

[Brief explanation of the drawing]

The figures show one 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 plan view of a large gear. 5 is a plan view showing the drive mechanism, FIG. 6 is a plan view showing the Vinci roller operating mechanism, and FIG. 7 is a side view showing the magnetic head mounting part with a portion cut away. Figure 8 is the front view of the same, Figure 9 is the rear view of the same,
0 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, FIG. 12 is a plan view showing the actuating part of the polarity reversal switch, and FIG. The figure is an electrical circuit diagram.

Claims (1)

[Scope of utility model registration request] A pair of capstan shafts with flywheels attached to the left and right sides of the magnetic head, and a pair of Vinci rollers that are alternately pressed against or separated from each capstan shaft are installed to switch the running direction of the magnetic tape. In a device that performs recording and playback using a multi-channel system by moving a magnetic head in the width direction of a magnetic tape, the magnetic head is constantly rotated in a fixed direction and the two capstan shafts are moved in opposite directions to each other. - A single motor that simultaneously rotates in the tape feeding direction, a pair of tape tension detection chips that are provided on the left and right sides of the magnetic head so that they can move forward and backward in the direction toward and away from the magnetic tape, and these two detection chips run. a trigger lock mechanism that is pressed against the magnetic tape and operates by receiving the tension through the detection chips when the tension of the magnetic tape is suddenly increased at the end of the tape; and a small gear that is constantly driven to rotate by the motor. and an eccentric cam whose radial dimension changes according to the position in the circumferential direction, and a height cam which changes the height dimension in the axial direction and changes the position of the magnetic head in the tape width direction as the magnetic head rotates. is held in a non-locked state with respect to the small gear by the trigger lock mechanism, and is released from the hold by the trigger lock mechanism when the trigger lock mechanism is activated by the tension of the magnetic tape; and the capstan shaft. When the large gear is released from the trigger lock mechanism, the large gear meshes with the small gear, and the large gear engages with the small gear. an actuating lever that, when driven by the eccentric cam, switches both Vinci rollers toward and away from their respective capstan shafts as the eccentric cam rotates; a reel stand provided on each of the left and right reel shafts; a swinging lever that is freely provided; an idler pulley that is rotatably supported on the swinging lever and can be selectively pressed against the left and right flywheels by swinging the swinging lever; When the Vinch rollers are switched toward and away from their corresponding capstan shafts, the reel stand provided on the reel shaft on the tape winding side and the idler pulley are connected to the support arm that supports each Vinch roller. The left and right 1 inserts the idler pulley into pressure contact with the flywheel attached to the capstan shaft on the side where the Vinci roller is separated, and transmits the rotational force of the flywheel to the reel shaft on the tape winding side.
An auto-reverse device for a tape recorder, characterized in that it is equipped with a pair of switching pulleys.