JPH05151656A - Magnetic recording reproducing device - Google Patents

Abstract

PURPOSE:To improve reliability by keeping an engaging relation between reel platform driving body whose rotary center is placed on a fixed position and the reel platform constant regardless of the kind of a tape cassette and transmitting torque for rotating the reel platform via the reel platform driving body. CONSTITUTION:In the case of a small cassette, reel platform moving frame bodies 17a and 17b are abutted on stoppers 40a and 40b and in the case of a large cassette, they are abutted on stoppers 41a and 41b. Since the frame bodies 17a and 17b continue to be pressed by a driving means, the frame bodies 17a and 17b are positioned on specified places, the reel platforms 5a and 5b are also positioned on specified places and their positions are maintained. When a cassette holder is moved, and the reel of the cassette is engaged with the reel platforms 5a and 5b to be positioned under the condition that the reel platform 5a and 5b are positioned on the specified places, each guide post 26 positioned in the opening part 44 of the cassette is moved, a tape 12 is pulled out and wound round a cylinder 30 at a specified angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus, and more particularly to an excellent magnetic recording / reproducing apparatus capable of carrying out magnetic recording / reproducing by mounting tape cassettes having different sizes and shapes.

[0002]

2. Description of the Related Art Home video tape recorders (VT
Depending on the application, the R) has a stationary VTR that uses a large-sized tape cassette with a large amount of magnetic tape wound, and is convenient for outdoor portable use in order to record or reproduce for a long time. There is a handy type VTR or video camera which uses a small tape cassette which is small and lightweight and has a relatively small amount of magnetic tape wound. In this case, the two VTRs have different configurations such as the spacing of the reel bases (reel shafts), and the tape cassettes used for the two VTRs naturally have different reel shaft spacings as well as external dimensions.

As a prior art of a magnetic recording / reproducing apparatus for such tape cassettes having different shapes and sizes, there is one described in Japanese Patent Publication No. 63-63978. Hereinafter, a conventional technique of the magnetic recording / reproducing apparatus disclosed in Japanese Patent Publication No. 63-63978 will be described with reference to the drawings. FIG. 5 is a plan view showing a tape drive mechanism in a conventional magnetic recording / reproducing apparatus, but since this figure shows the entire magnetic tape drive mechanism and is complicated, only an essential part thereof is extracted and enlarged. 6 and FIG. 7.

FIG. 6 corresponds to a small tape cassette 1 for a handy type VTR (hereinafter referred to as a small cassette).
FIG. 7 shows a state in which the internal mechanism of the magnetic recording / reproducing apparatus is arranged corresponding to a large-sized tape cassette 2 for a stationary VTR (hereinafter referred to as a large cassette).
3a and 3b are reel base moving substrates 5a and 5b which are rotatable around rotation center points 4a and 4b, and 5a and 5b are reel bases which are rotatably installed on the reel base moving substrates 3a and 3b. Reference numeral 6 is a tension lever which rotates about a rotation center point 7, 8 is a tension band, 9a and 9b are brake levers whose rotation center points are 10a and 10b, 11 is the above-mentioned reel base moving boards 3a and 3b, Tension lever 6
A fixed substrate to which other members (not shown) are attached, and 12 is a magnetic tape (hereinafter referred to as a tape). In such a configuration, the tension lever 6 rotates about the rotation center point 7 according to the tension of the tape 12, and one end of the tension band 8 fixed on the reel base moving substrate 3a is pulled. By doing so, the reel base 5a is braked and the tape tension is maintained at an appropriate value. That is, the tape tension control mechanism is constituted by the combination of the tension lever 6 and the tension band 8. When the tape is stopped, the brake levers 9a and 9b are driven by driving means (not shown) centering on the rotation center points 10a and 10b, and are rotated to brake the reel bases 5a and 5b to stop the reel bases 5a and 5b. maintain. In addition,
The rotation center point 4a of the reel base moving board 3a, one end of the tension band 8 and a part of the brake lever 9a overlap each other at the same position, but the positions in the height direction are different. They do not interfere with each other.

FIG. 7 is a view in which the reel base moving substrates 3a and 3b are rotated around the rotation centers 4a and 4b and positioned so as to correspond to the large cassette 2. Thus, the reel stand 5a, the brake lever 9a and the tension band 8 are
And a reel base moving board 3a on which the reel base 5b and the brake lever 9b are mounted.
The positions of the reel bases 5a and 5b are changed by rotating the. To accommodate the type of tape cassette.

FIG. 8 is a diagram for explaining a state in which the rotational torque is transmitted to the reel stand 5b in the state of the magnetic recording / reproducing apparatus corresponding to the small cassette 1. The idler 14 contacts both the motor pulley 13 and the reel stand 5b. The idler 14 relays the torque applied by the motor pulley 13 to the reel stand 5b. FIG. 9 is a diagram for explaining a state in which the rotational torque is transmitted to the reel base 5b in the state of the magnetic recording / reproducing apparatus corresponding to the large cassette 2, and the size of the cassette described in the above Japanese Patent Publication No. 63-63978. When the cassette type is detected by the detection means and the large cassette 2 is detected, the reel base 5b changes its position with respect to the motor pulley 13 to expand the reel shaft center interval,
As the position of the reel base 5b is changed, the position of the idler 14 is changed so that the idler 14 abuts and engages both the motor pulley 13 and the reel base 5b, and the torque given by the motor pulley 13 is transmitted to the reel base 5b.

[0007]

However, in the above conventional structure, when the type of tape cassette changes and the reel base moving boards 3a, 3b move, the motor pulley 13,
Each center makes an angle of the idler 14 and the reel base 5b is different from an angle theta ₂ in the case corresponding to an angle theta ₁ with the large cassette 2 when corresponding to the small cassette 1, the angle of the case corresponding to the small cassette 1 theta _When the value of ₁ becomes too small, the idler 14 receives a force that escapes from the motor pulley 13 and the reel stand 5b, while the angle θ ₁ corresponding to the small cassette 1 becomes a proper value. When 13 and the reel stand 5b are arranged, the angle θ ₂ corresponding to the large cassette 2 becomes too large, and a force acts such that the idler 14 is bitten between the motor pulley 13 and the reel stand 5b. Thus, as the angle theta ₁ and the angle theta ₂ of both proper angle in the case of corresponding to the large cassette 2 when corresponding to the small cassette 1 to position the idler 14, the motor pulley 13 and the reel base 5b However, there is a problem that it is difficult to apply an unnecessary lateral pressure to the reel stand 5b or the magnetic recording / reproducing apparatus itself must be enlarged. Even when the reel base 5a side is driven to rewind to the supply side reel, the side pressure is applied to the reel base 5a as in the case of the reel base 5b. In this way, the reel stand 5
When driving either a or 5b, the reel bases 5a and 5b receive the biasing force transmitted by the idler 14 directly, so that the structure of the reel bases 5a and 5b is made firm, and the positioning of the reel bases 5a and 5b is further enhanced. However, there is also a problem that it is necessary to do it firmly.

The present invention solves the above-mentioned problems of the prior art, does not apply unnecessary lateral pressure to the reel stand regardless of the size of the cassette, and complicates the structure of the reel stand to make the positioning member strong. It is an object of the present invention to provide a highly reliable magnetic recording / reproducing apparatus that maintains accuracy and is durable.

[0009]

In order to achieve the above object, a magnetic recording / reproducing apparatus of the present invention comprises a fixed substrate and a reel stand moving frame which can be rotated with respect to the fixed substrate about a rotation center point. A reel base driving body rotatably installed at the center of rotation of the reel base moving frame, and a reel base moving body that is constantly engaged with the reel base moving body on the reel base moving frame. A reel base which is rotatably installed and whose rotation is driven by a reel base drive; a means for applying a torque for rotating the reel base to the reel base drive; a means for detecting the type of a tape cassette mounted; A means for rotating and fixing the reel base moving frame at a predetermined position determined by the type of the detected tape cassette so that a plurality of types of tape cassettes having different reel center positions can be mounted. .

[0010]

Therefore, according to the structure of the present invention, even if the reel base moving frame rotates, the reel base driving body does not move and is in a fixed position, and the distance between the rotation axes of the reel base and the reel driving body is always constant. It is constant and the engagement state between the reel base and the reel drive body is constant regardless of the rotation position of the reel base moving frame body, and is driven to the reel base via the reel base drive body without directly applying side pressure to the reel base. Since the force can be transmitted and the torque for rotating the reel stand is constant regardless of the size of the cassette, the accuracy can be improved without complicating the structure of the reel stand or making the positioning member powerful. It is possible to maintain the magnetic recording / reproducing apparatus, and the magnetic recording / reproducing apparatus itself is not upsized.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the magnetic recording / reproducing apparatus of the present invention will be described below with reference to the drawings.

FIGS. 1 to 4 are views showing a main part of a magnetic recording / reproducing apparatus of the present invention. In FIGS. 1 to 4, the same members as those of the conventional example shown in FIGS. The same symbols as the names are attached.

1 and 2 are plan views showing a tape drive mechanism in a magnetic recording / reproducing apparatus of the present invention. FIG. 1 shows a case where a small cassette 1 is mounted on the magnetic recording / reproducing apparatus and a large cassette 2 is mounted on the magnetic recording / reproducing apparatus. Is shown. FIG. 3 shows A in FIG.
The cross-section of ₁ -O ₁ -O ₂ -A ₂ line is a sectional view seen from the direction of the arrow.

1 to 3, 1 is a small cassette, 2 is
Is a large cassette, 5a and 5b are reel bases, 6 is a tension lever that rotates about a rotation center point 7, 8 is a tension band, and 9a and 9b are brakes that rotate around rotation center points 10a and 10b. A lever, 11 is a fixed substrate to which each member constituting the tape drive mechanism and other members (not shown) are attached, 12 is a tape, 15a, 15b
Is a reel base driving body that freely rotates around the shafts 16a and 16b with respect to the fixed substrate 11 during operation (including rewinding)
Other than the above, braking is applied by the brake levers 9a and 9b. Reference numerals 17a and 17b are reel base moving frames for rotating the reel bases 5a and 5b, and 18a and 18b are reel bases 5.
It is an axis that serves as the center of rotation of a and 5b. 19a and 19b are the slip members 20 on the lower cylindrical portions of the reel stands 5a and 5b.
a, 20b, gears 21a, 21b and disc springs 22a, 22
After inserting b in a stack, the bushes press-fitted into the lower cylindrical portions of the reel stands 5a, 5b apply the pressing force of the disc springs 22a, 22b to the slip member 2 via the gears 21a, 21b.
0a, 20b. The gears 21a and 21b can rotate with respect to the lower cylindrical portions of the reel stands 5a and 5b while receiving the pressing force of the disc springs 22a and 22b. Reference numeral 23 is an idler for driving the rotation of the reel base driving body 15a or 15b, 24 is a rotation shaft of the idler 23, 25 is a tension post for transmitting the tension of the tape 12 to the tension lever 6, and 26 is a tape 1
2 is a plurality of guide posts for forming a predetermined traveling path, 27 is a capstan for giving the tape 12 a constant traveling speed, 28 is a pinch roller for sandwiching the tape 12 with the capstan 27, 29 Is capstan 2
7, a flywheel that simultaneously rotates coaxially with 7, and also serves as a pulley for transmitting the rotation to the reel stands 5a and 5b via an idler 23, etc., and 30 has a magnetic head or the like for contacting with the tape 12 for recording and reproducing. Cylinder 31 is a spring for rotating the tension lever 6 in the clockwise direction around the rotation center point 7 and 32a and 32b are brake levers 9a and 9b for stopping the tape 12 from running.
a is a spring for abutting against a and 15b, 33 is a brake contact position with respect to the reel base driving bodies 15a and 15b when the large cassette 2 is mounted, 40a and 40b are reel base moving frames 17a and 17b, and a small cassette. 1, stoppers 41a and 41b contact when the reel base moving frames 17a and 17b are in positions corresponding to the large cassette 2, and 43a and 43b move left and right. A cam that controls the operation of the brake levers 9a and 9b, and 44 indicates an opening of the cassette.

4 (a) and 4 (b) show the rotation drive section 42, and 34 is an intermediate idler for driving the rotation of the idler 23. Reference numeral 35 denotes an intermediate idler 34 and an idler 23 engaged with each other, and the idler 23 is wound on a reel base driving body 15a side or a supply side reel base driving body 15b.
The idler moving board for moving the idler 23 to engage with either side, 36 is a slip member provided between the intermediate idler 34 and the idler moving board 35, and 37 is a flange of the intermediate idler 34 and the shaft 38. A disc spring 39 provided between the intermediate belt and the portion is a square belt for transmitting the rotation of the flywheel 29 also serving as a pulley to the intermediate idler 34.

The operation of the magnetic recording / reproducing apparatus of this embodiment constituted by the members described above will be described below.

First, when the tape running is stopped, the cams 43a and 43b are moved in the direction of the arrow driven by a driving means (not shown), and the brake levers 9a and 9b are pulled by the springs 32a and 32b, and the brake levers 9a and 9b rotate about the center point 10a. The reel base driving bodies 15a and 15b are braked by rotating around 10b to maintain the stopped state of the reel bases 5a and 5b. In this state, when the small cassette 1 or the large cassette 2 is inserted into the cassette holder (not shown) of the magnetic recording / reproducing apparatus, the size of the cassette can be increased or decreased by the same means as described in Japanese Patent Publication No. 63-63978. 1 is detected when the cassette is the small cassette 1 and in the state shown in FIG. 2 when the cassette is the large cassette 2, the reel stand moving frame members 17a and 17b are not shown. The drive means rotates the shafts 16a, 16b (see FIG. 3) as a center, and in the case of the small cassette 1, the reel stand moving frame bodies 17a, 1
7b abuts the stoppers 40a, 40b, and the large cassette 2
In the case of, it contacts the stoppers 41a and 41b. Since the reel base moving frames 17a and 17b are continuously urged by the driving means, the reel base moving frames 17a and 17b are positioned at predetermined positions, and the reel bases 5a and 5b are also positioned at predetermined positions. maintain. Reel stand 5a, 5
In this state in which b is positioned at a predetermined position, the cassette holder moves and the reel of the cassette moves to the reel stands 5a and 5b.
1 and 2, each of the plurality of guide posts 26 positioned in the opening 44 of the cassette moves to engage the tape 12 and the tape 12 is pulled out to the cylinder 30 at a predetermined angle. And the tape path is formed.

When the recording or reproducing operation is started, the cams 43a and 43b move in the direction opposite to the arrow, and push the protrusions of the brake levers 9a and 9b to move the brake levers 9a and 9b to the pivot center point 10a. , 10b are rotated to release the contact with the reel base moving frame bodies 17a, 17b, and the reel bases 5a, 5b can be freely rotated in response to external driving. The tape 12 is pressed against the capstan 27 by the pinch roller 28 and runs at a constant speed by the rotation of the capstan 27. The capstan 27 is coaxial with the flywheel 29, and the flywheel 29 is the capstan 27.
It rotates at the same angular velocity as. The flywheel 29 also serves as a pulley for the square belt 39.
The rotation of 9 is transmitted to the intermediate idler 34 by the square belt 39.

The structure of the rotary drive unit 42 including the intermediate idler 34 and the idler 23 is shown in FIGS. 4A and 4B. FIG. 4A is a plan view of the rotary drive unit 42.
(B) shows the longitudinal cross-sectional view. Intermediate idler 3
Since 4 is pressed against the idler moving base plate 35 by the disc spring 37 via the slip member 36, the rotation of the intermediate idler 34 is transmitted to the idler moving base plate 35,
When the flywheel 29 rotates in the direction of the arrow, the intermediate idler 34 rotates in the direction of the arrow A shown in FIG. With the rotation of the intermediate idler 34 in the direction of the arrow A, the idler moving board 35 moves the shaft 38 of the intermediate idler 34.
Is rotated in the direction of arrow B with the fulcrum as a fulcrum, the idler 23 engages with the reel base driving body 15b as shown in FIG. 1 or 2, and the reel base driving body 15b is rotated in the direction of the arrow. Once idler 23 is reel base driver 15b
After engaging with the idler moving board 35, the idler moving board 35 stops its rotation and maintains its position, and slip occurs at the slip member portion sandwiched between the idler moving board 35 and the intermediate idler 34.
The intermediate idler 34 rotates only the reel base driving body 15b via the idler 23.

The rotation of the reel base driver 15b in the direction of the arrow is transmitted to the reel base 5b, and the reel base 5b is rotated in the direction of the arrow to wind the tape 12 onto the reel of the cassette. In this way, the rotation of the flywheel 29 causes the reel stand 5 to move.
When the rotation of b is driven, the reel stand 5b is sandwiched by the capstan 27 and the pinch roller 28, and tries to rotate at a speed higher than the rotation speed required for winding the tape 12 running at a constant speed on the reel. .. However, as shown in FIG. 3, the reel base 5b is provided with the slip member 2 between the reel base 5b and the gear 21b whose rotation is driven by the reel base driving body 15b.
0b is sandwiched between the gear 21b and the disc spring 22b from below.
Since it is pressed by and presses the slip member 20b,
When tension is applied to the tape 12, slip occurs between the reel base 5b and the gear 21b, and the reel base 5b rotates at a rotation speed suitable for constant-speed running of the tape 12 to wind the tape 12 by the reel. In this case, the gear 2 of the reel stand 5b
The torque for driving 1b is constant regardless of the size of the cassette.

In the meantime, in the tensioning mechanism shown in FIGS. 1 and 2, the tape 12 is the tension post 2.
5 and the tension lever 6 around the rotation center point 7
Rotate counterclockwise. The tension lever 6 has one end fixed to the fixed base plate 11 and pulls the other end of the tension band 8 which is in contact with the outer circumference of the reel base driving body 15a for a half circumference. The counterclockwise rotation of the tension lever 6 drives the reel base. It acts in a direction that weakens the braking exerted on the body 15a by the spring 31. When the braking applied by the spring 31 to the reel base driving body 15a is weakened, the tape 1
The tension of No. 2 becomes small, and the braking applied to the reel base driving body 15a by the spring 31 becomes strong, so that the tension of the tape 12 becomes strong again. In this way, the tension of the tape 12 and the spring 31
The braking force applied by the tape keeps balance 1
A proper back tension of 2 is maintained.

When the tape 12 is wound on the side of the supply reel, the flywheel 29 rotates in the direction opposite to the arrow in FIGS. 1 and 2, and the intermediate idler 34 in FIG. The idler moving board 35 rotates in the direction opposite to A, and the idler moving substrate 35 also rotates in the direction opposite to arrow B, so that the idler 23 and the reel stand 5b are disengaged from each other, and the idler 23 moves to the reel stand driving body 15a. Engage. This state is shown in FIG. 1 and FIG.
It is indicated by a dashed line. Further, in FIG. 3, the center of the rotary shaft 24 of the idler 23 moves from A to B. As the idler 23 moves and engages with the reel base driving body 15a in this manner, the reel base driving body 15a and the reel base 5a rotate in the direction of the arrow as shown in FIGS. The winding on the supply reel is performed.

According to the magnetic recording / reproducing apparatus of the present embodiment, which has been described above, when the tape 12 is wound on the take-up reel side, the relative positions of the intermediate idler 34, the idler 23, and the reel stand drive body 15b are as follows. Small cassette 1 shown in FIG.
2 and the case of the large cassette 2 shown in FIG. 2, the angle θ formed by the center of the intermediate idler 34, the center of the idler 23, and the center of the reel base driving body 15b is always constant, and even if the idler 23 is used. Since the biting angle of the idler 23 can be arbitrarily selected, the degree of freedom in design can be increased. In addition, the reel base driver 15b and the reel base 5b
The positional relation between the reel base moving frame 17b is regulated to a constant value, and the rotational force of the idler moving base plate 35 is applied to the reel base driving body 15b. The reel base driving body 15b is directly mounted on the fixed base plate 11. Since it is firmly held by 16b and lateral pressure is not directly applied to the reel base 5b, it does not adversely affect the positioning accuracy of the reel without complicated and robust manufacturing unlike the conventional example. that's all,
Although the effect of the present embodiment has been described in the case of winding the tape 12 on the take-up reel side, the same is true for the case of winding the tape 12 on the supply-side reel.

[0024]

As is apparent from the above description, in the magnetic recording / reproducing apparatus of the present invention, regardless of the type of tape cassette, the engagement between the reel base driving body whose rotation center is at the fixed position and the reel base is fixed. , Is configured to be kept constant,
Since the torque to rotate the reel stand can be transmitted through the reel stand driving body, the contact angle of the idler can be freely and properly selected, and the reel stand is not directly subjected to the side pressure of the idler, so that the reel stand maintains accuracy. It is possible to realize a magnetic recording / reproducing apparatus having high accuracy and reliability, without requiring excessive strength, rationalization in design, and without increasing the size of the apparatus itself.

[Brief description of drawings]

FIG. 1 is a plan view in which a tape drive mechanism in one embodiment of a magnetic recording / reproducing apparatus of the present invention is applied to a small cassette.

FIG. 2 is a plan view in which the tape drive mechanism in one embodiment of the magnetic recording / reproducing apparatus of the present invention is applied to a large cassette.

FIG. 3 is a sectional view taken along line A ₁ -O ₁ -O ₂ -A _{2 in} FIG.

FIG. 4A is a plan view of the rotary drive unit, and FIG. 4B is a vertical cross-sectional view of the rotary drive unit.

FIG. 5 is a plan view of a tape drive mechanism of a conventional magnetic recording / reproducing apparatus.

FIG. 6 is a plan view of a main part when a conventional magnetic recording / reproducing apparatus is applied to a small cassette.

FIG. 7 is a plan view of a main part when the device is applied to a large cassette.

FIG. 8 is a plan view of a drive unit when the conventional magnetic recording / reproducing apparatus is applied to a small cassette.

FIG. 9 is a plan view of a drive unit when the device is applied to a large cassette.

[Explanation of symbols]

1 Small cassette (tape cassette) 2 Large cassette (tape cassette) 5a, 5b Reel stand 11 Fixed substrate 15a, 15b Reel stand driver 16a, 16b Axis (rotation center point) 17a, 17b Reel stand moving frame 40a, 40b Stoppers (Fixing Means) 41a, 41b Stoppers (Fixing Means) 42 Rotational Drive Unit (Means for Applying Torque to Reel Base Drive Body)

Claims (1)

[Claims] 1. A magnetic recording / reproducing apparatus capable of mounting a plurality of types of tape cassettes having different reel center positions, the reel base moving frame being rotatable with respect to the fixed substrate and the fixed substrate. Body, a reel base driving body rotatably installed at the center of rotation of the reel base moving frame, and the reel base moving on the reel base moving frame by always engaging the reel base driving body. A reel base that is rotatably mounted on the frame and whose rotation is driven by the reel base drive; a unit that applies a torque to rotate the reel base to the reel base drive; A magnetic recording / reproducing apparatus comprising means for detecting a type and means for rotating and fixing the reel base moving frame at a predetermined position determined by the detected type of the tape cassette.