JPH0544111B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape recorder using a direct drive system, and more particularly to a magnetic shielding device for magnetically shielding its motor, magnetic tape, magnetic head, etc. As is well known, in a conventional tape recorder, a pair of reel shafts, a flywheel (capstan), etc. are transmitted from a single drive motor through a rotation transmission mechanism consisting of a belt, a pulley, an idler, etc.
The tape is driven by rotation. By the way, the conventional tape running means as described above has various disadvantages such as a large number of parts, a complicated structure, and difficulty in manufacturing, as well as an increase in size and weight. In addition, in terms of sound quality, since there is a loss of rotational force due to the rotation transmission mechanism being interposed between the drive motor, reel shaft, and flywheel (capstan), it is especially important to improve the wow and flutter values. Currently, it is difficult to do so, and there are limits to the improvement of sound quality. Therefore, in recent years, a so-called direct drive (DD) has been developed in which a pair of reel shafts and a rotary shaft of a flywheel (also used as a capstan) constitute multiple motors that are each directly connected to a rotor.
Tape recorders using this method have been developed. In other words, by rotating the tape recorder's reel shaft, flywheel (capstan), etc. using a direct drive system, conventional rotation transmission mechanisms such as belts, pulleys, and idlers are no longer necessary, and the structure is simple and easy to manufacture. , it is suitable for compactness and weight reduction, and can further improve wow and flutter values, contributing to improved sound quality. In addition, the rotational speed and rotational direction of the reel shaft and flywheel (capstan) can all be changed electrically, which facilitates simple configuration changes and allows for soft-touch operation of various controls. It has various advantages, such as being able to However, the tape recorders that are currently being developed using the direct drive system are still in the development stage, and despite having the various advantages mentioned above, there are currently no configurations that actively utilize these advantages. However, detailed development is strongly desired from various aspects. This invention was made based on the above circumstances, and is an extremely good invention that can prevent the leakage magnetic field from the motor from having an adverse effect on the magnetic neep, magnetic head, etc., and also contributes to miniaturization and weight reduction with a simple configuration. An object of the present invention is to provide a magnetic shielding device for a tape recorder. Before explaining one embodiment of the present invention, types of tape drive mechanisms in tape recorders and driving principles of motors used in the direct drive system will be briefly explained. first,
There are three types of tape drive mechanisms, as shown in FIGS. 1a to 1c. That is, the one shown in FIG. 1a shows the most common configuration as a normal tape drive mechanism. , 12, via a pair of guide rollers 14, 15, so as to be movable in the directions of arrows A and B in the figure. When the tape 13 is running at a constant speed, the tape 13 is moved between the guide rollers 14 and 15 by a capstan 17 that is coaxially provided with the flywheel 16.
and the pinch roller 18, as indicated by arrow A in the figure.
It runs at a constant speed in the direction of the vehicle. In addition, the one shown in FIG. 1b has two flywheels 16 and 1 between both guide rollers 14 and 15.
9 and pinch rollers 18, 21 which are in pressure contact with capstans 17, 20, which are provided coaxially with the flywheels 16, 19, respectively, and have an auto-reverse function. This configuration is particularly adopted for tape recorders with And tape 1
3 is the capstan 17, 20 and the pinch roller 1
8 and 21, respectively, and run at a constant speed in directions A and B in the figure. Furthermore, the one shown in FIG.
and a pinch roller 1 that is pressed against a capstan 17 that is provided coaxially and integrally with the flywheel 16.
8, which is a so-called center capstan type, and is particularly used in micro cassette tape recorders and the like. And tape 13
is clamped between a capstan 17 and a pinch roller 18, and is run at a constant speed in the direction of arrow A in the figure. Next, the driving principle of the motor used in the direct drive method will be explained. As shown in FIG. 2a, this motor has a rotating shaft 22 of a rotor magnet 22 that is approximately disk-shaped and has a slight thickness.
1 is rotatably supported by a bearing 24 attached to a printed wiring board 23. The other end of the rotating shaft 221 passes through a bearing 26 attached to a tape mounting board 25 of the tape recorder and protrudes above the board 25 in the figure.
This protruding part is formed into a capstan shape,
A reel stand is attached to it. In addition, as shown in FIG. 2b, the lower surface of the rotor magnet 22 in FIG. ing. Four stator cores 271 to 274 are arranged on the surface of the printed wiring board 23 facing the magnetic pole surface of the rotor magnet 22 in a positional relationship as shown in FIG. 2b. These stator cores 271 to 274 have coils W ₁ , W _{3 ′} , W 2 , W 4 ′, W ₃ , W 3 ′, W 2 , W ₄ ′, W ₃ ,
It is formed by laminating W ₁ ′, W ₄ , and W ₂ ′. However, the coils W ₁ to W ₄ are wound in the same direction,
The coils W ₁ ′ to W ₄ ′ are also wound in the same direction. Further, on the surface of the printed wiring board 23, two Hall elements are installed in the same positional relationship as shown in FIG. 2b.
H ₁ and H ₂ are arranged. Then, each of the above-mentioned coils W ₁ to W ₄ and W ₁ ′ to
W ₄ ' and Hall elements H ₁ and H ₂ are connected as shown in FIG. 3a. In this circuit, the Hall element H ₁ generates an output that turns on the transistors Q ₁ and Q ₂ when N-pole and S-pole magnetic fields are respectively applied thereto. Further, the Hall element H ₂ generates an output that turns on the transistors Q ₃ and Q ₄ when each of the N-pole and S-pole magnetic fields is applied thereto. Here, FIG. 3b shows the rotor magnet 2
2. The positional relationships among the coils W ₁ to W ₄ , the coils W ₁ ′ to W ₄ ′, and the Hall elements H ₁ and H ₂ are shown in a plan view for convenience, and the operation will be explained with reference to this drawing. First, as shown in Figure 3b, the Hall element
Assuming that H ₁ is opposed to the magnetic pole N ₁ of the rotor magnet 22, the Hall element H ₁ turns on the transistor Q ₁ due to the action of its N pole. Then, current flows through the coils W ₂ and W ₂ ' in the direction shown in b in the same figure, and N and S pole limits occur on each coil W ₂ and W ₂ '. Therefore, attractive force and repulsive force in the direction of the arrow in the figure are generated between the magnetic field generated by the coils W ₂ and W ₂ ' and the magnetic pole of the rotor magnet 22, and the rotor magnet 22 is moved in the direction of the arrow C in the figure. rotated in the direction Next, when the rotor magnet 22 rotates and the Hall element H ₂ faces the magnetic pole N ₁ of _the rotor magnet ₂₂ as shown in _FIG . A current flows through ' as shown in b in the same figure. For this reason, the coil
N-pole and S-pole magnetic fields are generated on W ₃ ' and W ₃ , respectively, and the rotor magnet 22 is thereby rotated. Similarly, rotational torque is generated in the state shown in FIG. 3b, and the rotor magnet 22
The rotation of the image continues. The motor configured as above has each coil W ₁ to W ₄ ,
By appropriately setting the winding direction of W ₁ ′ to W ₄ ′ and the magnitude of the applied current, the rotation direction and rotation speed of the rotor magnet 22 can be arbitrarily set. Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. In the examples described below, unless otherwise specified, Figure 1 a
A tape recorder having a tape drive mechanism of the type shown in FIG. 2 will be described, and the Hall elements H ₁ and H ₂ shown in FIGS. 2 and 3 will be omitted from the drawings for simplicity. That is, in FIG. 4, 31 and 32 are rotor magnets, and these rotating shafts 311 and 321
One end portion (lower end portion in the drawing) of is rotatably supported by bearings 34 and 35 attached to the printed wiring board 33 as described later. In addition, each of the rotating shafts 31
The other end (upper end in the figure) of 1,321 is inserted through bearings 37 and 38 respectively attached to a tape mounting board 36 of a tape recorder, and is projected upward in the figure of the board 36. There is. And the rotating shaft 31
The protruding portion of the rotary shaft 321 is directly formed as a capstan 39, which serves as a rotating body for driving the tape at a constant speed. A reel 40 is fitted. Further, as described above, a plurality of stator cores 41,
..., 41 and 42, ..., 42 are arranged. A portion consisting of the rotor magnet 31 and stator cores 41, . . . , 41 constitutes a capstan motor 43 , and a portion consisting of the rotor magnet 32 and stator cores 42, . 44 . Further, the other reel motor will be described later, but has a similar configuration. The reel 40, the other reel (not shown), and the capstan 39 are fitted into and inserted into a reel hub (not shown) and a capstan insertion hole (not shown) of the tape cassette 45, respectively, as shown by the two-dot chain line in the figure, for example. In addition, the substrate 36
A head chassis 47 on which a recording/reproducing head 46 is attached is arranged in parallel above. This head chassis 47 is supported so as to be slidable in the direction of the arrow in the figure, and is used to move the recording/reproducing head 46 toward and away from the tape (not shown) of the tape cassette 45. Further, a connector 48 is connected to one end of the printed wiring board 33, and is connected to other printed wiring boards, a power source, etc. (not shown). Here, as shown in FIG. 5, the stator cores 41, . . . , 41, 42, . . . , 42 and the stator cores 49, .
9 are arranged on the printed wiring board 33, for example, four at a time. Further, a bearing 50 for a rotating shaft of a rotor magnet, which will be described later, is attached to the center portion surrounded by the stator cores 49, . . . , 49 of the other reel motor. Further, the printed wiring board 33 includes each stator core 41,..., 41, 42,..., 42, 4.
9, .
3 is formed. As shown in FIG. 6, these FG patterns 51 to 53 are connected to each rotor magnet 31, 32 and each rotating shaft 311, 3 of the rotor magnet 54 of the other reel motor.
21 and 541 are supported by bearings 34, 35, and 50, respectively, and each rotor magnet 3
1, 32, and 54 in FIG. 6. Note that the other reel 55 is fitted onto the upper part of the rotating shaft 541 of the rotor magnet 54 via a reel stand (not shown). The rotor magnet 54 and the stator cores 49, . . . , 49 constitute the other reel motor 56 . In addition, each stator core 41, ..., 4
1, 42, . . . , 42, 49, . It is something that As shown in FIG. 7, each stator core 41 of each rotor magnet 31, 32, 54,
......,41,42,...,42,49,...,4
As previously shown in FIG. 2B, a magnetic pole portion 57 for rotationally driving the rotor magnets 31, 32, and 54 is formed on the surface facing the rotor magnet 9. As shown in FIG.
In addition, each FG of rotor magnets 31, 32, and 54
A magnetic pole portion 58 is formed in a peripheral portion facing the patterns 51 to 53, in which S and N pole magnetic fields are alternately arranged more densely than the magnetic pole portion 57. Here, the interaction between the FG patterns 51 to 53 and the magnetic pole portion 58 will be described later, and tape running will be explained first. First, a tape recorder employing this direct drive system has a touch switch structure in which a plurality of controls (not shown) are used to set the tape recorder in a predetermined operating state or stop state, and when any one of the controls is operated,
An LSI (not shown) dedicated to tape recorder control detects that the touch switch is turned on, and
It has a so-called logic configuration in which the LSI generates a corresponding output signal to control the rotation, stop, etc. of the capstan 39 and reels 40, 55. Therefore, for example, if you operate the fast forward or rewind operator, the LSI will control the reel motor 4 .
Outputs a signal to the stator cores 42,..., 42 or 49,..., 49 to rotate the rotor magnet 32 or 54 at a rotation speed and direction corresponding to the fast forward or rewind state. However, the tape is fast forwarded or rewound. Furthermore, when the tape constant speed running operator (recording or playback operator) is operated, the LSIs are operated by the stator cores 41, . . . of the capstan motor 43 and the reel motor 44 , respectively.
A signal is outputted to 41 and 42, . . At this time, it goes without saying that a pinch roller (not shown) is pressed against the capstan 39 via a tape. In addition, in the case of the dual capstan type tape recorder shown in FIG. 1b, a stator core for the other capstan motor is mounted at a predetermined position on the printed wiring board 33, as shown in FIG. 5
9,...,59 and FG pattern 60, bearing 6
1, and the rotor magnet 31
What is necessary is to rotate a rotor magnet (not shown) similar to that shown in FIG. Here, in the configuration shown in FIG. 6 again,
The effects of the FG patterns 51 to 53 and the magnetic pole portion 58 will be explained. That is, when each of the rotor magnets 31, 32, and 54 rotates, each of its magnetic pole parts 58 rotates on the FG patterns 51 to 53, which are coils. An electromotive force (hereinafter referred to as FG signal) having a frequency and phase corresponding to the rotational speed of each rotor magnet 31, 32, 54 is generated. This FG signal is transmitted to the capstan motor 43 and the reel motor 4.
4, 56 , and is used as follows. First , the capstan motor 43 will be explained. As shown in FIG.
The FG signal obtained from the FG pattern 51 is supplied to one input end of each of the φ-V conversion circuit 63 and the F-V conversion circuit 64 via the amplifier circuit 62.
This φ-V conversion circuit 63 and F-V conversion circuit 64
A reference frequency signal obtained by frequency-dividing the output signal from the reference oscillation circuit 65 by a frequency dividing circuit 66 is supplied to the other input terminal of each of the reference oscillation circuits 65 and 66, respectively. Based on the voltage supplied from the reference voltage generation circuit 67, the φ-V conversion circuit 63 and the F-V conversion circuit 64 generate a voltage corresponding to the phase difference and frequency difference between the FG signal and the reference frequency signal. are output to the comparison circuit 68, respectively. This comparison circuit 68 is a signal that controls the rotational speed of the capstan motor 43 so as to eliminate the difference between the output voltages from the φ-V conversion circuit 63 and the F-V conversion circuit 64, or so that the voltage difference becomes a predetermined value. is supplied to the stator cores 41, . . . , 41 of the capstan motor 43 via an amplifier circuit 69 and a predetermined drive circuit 70. Therefore, the capstan motor 43
Since the rotation speed is constantly controlled so that the FG signal is equal to the phase and frequency of the reference frequency signal, the rotation speed can always be kept constant, and the wow and flutter values can be significantly improved. be. Also, from the above FG pattern 51
By counting the FG signal by the counter circuit 71 and displaying it by the digital display circuit 72, it is possible to display the tape running amount or the tape running time in the tape constant speed running state. Furthermore, when the tape is running at a constant speed,
The FG signal is counted by a counter circuit 73, and when the count value reaches a predetermined value, a predetermined drive mechanism 74 is operated to cause the tape recorder to switch modes such as automatic stop, auto repeat, or auto reverse operation. It may be done as follows. Next, the reel motors 44 and 56 will be explained. As shown in FIG. 10, the reel motors 44 and 56 are rotationally driven in accordance with the output from the LSI 75 dedicated to controlling the tape recorder, as described above. It is something that However, in FIG. 10, only fast forwarding and rewinding are shown for simplicity. That is, when a fast forward/rewind operator (not shown) having a touch switch structure is operated, a predetermined signal is sent to the fast forward/rewind input terminal (I.FF) of the LSI 75 via the connection terminals 761, 762 in accordance with the operation. ), (I.REW). Then, LSI
75 determines which of the fast forward and rewind operators has been operated, and drives circuits 771 and 77 from the fast forward and rewind output terminals (O.FF) and (O.REW).
A drive signal is output to 2. This drive circuit 771,
772, when a drive signal is supplied, each stator core 42,..., 42 of the reel motor 44 , 56
and 49 , . Then, the reel motors 44 and 56 are rotated. When the tape constant speed running operator is operated, the reel motor 44 and the capstan motor 43 are rotationally driven from the tape constant speed running output end (not shown) of the LSI 75 via a drive circuit (not shown). It outputs a signal. The FG signal from the FG pattern 52 of the reel motor 44 is counted by a counter circuit 78, and the count value is displayed by a digital display circuit 79. In this way, the amount of tape running can be displayed in both constant tape speed and high speed tape running states. Further, the presence or absence of the FG signal from the FG pattern 53 of the reel motor 56 is detected by a detection circuit 80. That is, since the reel motor 56 is constantly rotating in the tape running state, the FG signal is continuously supplied to the detection circuit 80. At this time, the detection circuit 80 does not output any drive signal to the mode switching mechanism 81, which will be described later. For example, when the tape reaches the end and the rotation of the reel motor 56 is stopped, the detection circuit 80 detects that the FG signal is no longer input for a predetermined period of time, and the mode switching mechanism 81 Outputs a drive signal. This mode switching mechanism 81 includes, for example, a so-called automatic stop mechanism (ASO) that switches from a tape running state to a tape running stopped state, an auto repeat mechanism that switches between a tape playback state and a tape rewinding state, and a one-sided tape recording and playback state. Various mechanisms are employed to switch the mode of the tape recorder, such as an auto-reverse mechanism that switches between the recording and playback state on the other side. Then, a drive signal from the detection circuit 80 is supplied to the mode switching mechanism 81, whereby a mode switching operation is performed. This means that, for example, when the tape reaches its end,
When the rotation of the reel motor 56 is stopped, etc.
It is possible to switch modes such as automatic stop, auto repeat, and auto reverse operation. Here, for example, the signal is supplied to the detection circuit 80.
The FG signal is the FG pattern 5 of the reel motor 44 .
2, the reel motor 56 has
The FG pattern 53 may not be provided,
Conversely, the FG signal supplied to the counter circuit 78 may be obtained from the FG pattern 53 of the reel motor 56 , and the reel motor 44 may not be provided with the FG pattern 52. This can be changed as appropriate depending on circumstances. Therefore, according to the above configuration, first, each capstan motor 43 and reel motors 44 and 56 for rotationally driving the capstan 39 and the pair of reels 40 and 55, etc. necessary for tape running, are Since the motors 43 and 4 are integrally assembled on one printed wiring board 33,
4 and 56 , it is not necessary to separately provide a support member, etc., and the structure can be extremely simplified and the weight can be reduced. In addition, each stator core 41, ..., 41, 4 is directly attached to the printed wiring board 33.
Since the wires 2, . . . , 42, 49, . Furthermore, since the capstan motor 43 is always controlled to a constant rotational speed by comparing the FG signal and the reference frequency signal, the wow and flutter values can be significantly improved. In addition, the reel motors 44 and 56 operate each stator core 4 according to the fast forwarding, rewinding, and constant speed tape running states.
2, ..., 42 and 49, ..., 49, their rotational speeds and directions are determined, so switching is easy, and the actual moving parts are rotor magnets. net 32,5
4, which greatly simplifies the configuration and contributes to reduction in size and weight. Note that the rotor magnets 31, 32, and 54 do not need to be made up entirely of magnets;
8 may be stacked. Here, using the FG signal from the capstan motor 43 or the reel motors 44 and 56 ,
Since the modes of the automatic stop mechanism, auto repeat mechanism, auto reverse mechanism, etc. are switched, reliable mode switching operation can be performed with an extremely simple configuration. In addition, since the amount of tape travel is displayed by counting the FG signals from the capstan motor 43 or the reel motors 44 and 56 , there is no need to provide a separate tape counter mechanism. This can also contribute to simplifying the configuration and making it smaller and lighter. Next, details of the bearings 34, 35, and 50 attached to the printed wiring board 33 will be explained. That is, as shown in FIGS. 11a and 11b, each bearing 3
Reference numerals 4, 35, and 50 are made of a synthetic resin material such as Diuracon, which has a smooth surface, and are formed into a substantially cylindrical shape, and are outsert-formed at predetermined positions on the printed wiring board 33. And each bearing 34, 3
Among the rotor magnets 31, 32, 50, the portions of the printed wiring board 33 that protrude toward the side facing the rotor magnets 31, 32, 54 are provided with the rotor magnets 31, 32, 5
Recesses 341, 351, 501 into which the rotation shafts 311, 321, 541 of No. 4 are fitted are formed, respectively. Also, among the bearings 34, 35, 50, the rotor magnets 31, 32, 54 of the printed wiring board 33
The portions protruding toward the surface not facing the bearings 34, 35, and 50 are connected to each other by runners 821 to 823 formed integrally with the bearings 34, 35, and 50. Therefore, the bearings 34, 35, 50 of the capstan motor 43 and the reel motors 44 , 56 are formed as outserts on the printed wiring board 33, and these bearings 34, 35, 50 are connected to the runner 821.
Since the bearings 34, 35, 50 are connected to each other by 823, the bearings 34, 35, 50 can be easily formed, the printed wiring board 33 can be reinforced, and the rotor magnets 31, 32, 54 can be connected easily. It can be stably supported. In addition, in the case of the dual-capstan type tape recorder mentioned above, as shown in FIGS. Approximately loop-shaped, approximately H-shaped, approximately U-shaped, etc. depending on the
It can be formed into various shapes. Furthermore, in the case of a center capstan type tape recorder, as shown in FIG.
4 and 50 can be connected by a substantially T-shaped runner 827. Next, as shown in FIG. 14a, the substrate 36
For example, a magnetic shield member 83 is attached to the surface facing each rotor magnet 31, 32. By doing this, the rotor magnets 31, 32 and the stator cores 41,..., 4
The magnetic field radiated from 1, 42, ..., 42 etc. is
This makes it possible to prevent the magnetic tape of the tape cassette 45, the recording/reproducing head 46, etc. from being adversely affected. Also, a capstan motor 43 , a reel motor 44 , a magnetic tape and a recording/reproducing head 4,
In order to magnetically shield the rotor magnet 3 and the
The rotor magnets 31, 32 and the stator cores 41, . . . , 41 and 42, . 4
2 may be covered. In the magnetic shielding means shown in FIG. 14a, the magnetic shielding member 83 may be provided on the upper surface side of the substrate 36 in the figure. Further, especially when the magnetic shielding member 83 is provided on the substrate 36, it is more effective in terms of magnetic shielding if the substrate 36 is made of a synthetic resin material. Then, as described above, each rotor magnet 3
1, 32, 54 and stator core 41, ..., 4
1, 42, . . . , 42, 49, . This is a feature of the present invention. Next, as shown in FIG.
At the top, a magnetic shielding member 85 is installed approximately vertically between the capstan motor 43 , the reel motor 44 , and the other reel motor 56 (see FIG. 6), which is not visible in FIG. .
That is, this magnetic shielding member 85 is located at the 16th point when the printed wiring board 33 is viewed from above in FIG.
As shown in the figure, the parts where the capstan motor 43 and the reel motors 44 and 56 are constructed are as follows:
Each of them is installed in a substantially T-shape so as to be magnetically shielded. Then, by magnetically seeding each capstan motor 43 and reel motor 44 , 56 with the magnetic shield member 85 as described above, each rotor magnet 31, 32, 54 and stator core 41,..., 41, 42,...,4
This can prevent leakage of the magnetic fields generated from each of the motors 2, 49, . . . , 49 from adversely affecting the rotation of the other motors 43 , 44 , 54 . This is especially true for the reel motors 44 , 5 .
The leakage of the magnetic field generated from the rotor magnets 32, 54 and the stator cores 42,..., 42, 49,..., 49 of the capstan motor 43
If the rotation of the capstan motor 43 is affected,
This is especially important since there is a problem that the rotational speed of the motor is not constant, leading to deterioration of wow and flutter. Further, in the case of the dual-capstan type tape recorder, as shown in FIG.
By arranging the motors in the same manner, magnetic shielding can be achieved between the motors. Here, as shown in FIG. 18a, each stator core 41, ..., 41, 42, ..., 42 of the capstan motor 43 and the reel motor 44 is
The rotor magnets 31, 3 of the printed wiring board 33
It may be arranged on the side of the second surface 332 opposite to the first surface 331 facing 2. In this way, stator cores 41, . . . , 41, 4 are placed on the second surface 332 side of printed wiring board 33
2, . A magnetic shielding member 88 that magnetically shields between the stator cores 41, 41, 42, 42 may be installed. In addition, if necessary, as shown in FIGS. 18b and 18c, the first surface 3 of the printed wiring board 33 may be
Magnetic shielding members 87 and 88 are installed only on the 31 and second surface 332 sides, respectively, between the rotor magnets 31 and 32 and between the stator cores 41, . . .
. . , 41, 42, . . . , 42 may be magnetically shielded. Further, as a means for magnetically shielding between the capstan motor 43 and the reel motor 44 , it is also possible to realize the means shown in FIGS. 19a and 19b. That is, in FIG. 19a,
The rotating shaft 311 of each rotor magnet 31, 32,
321, each rotor magnet 3
Printed wiring boards 89 provided facing each other every 1,32
Through holes 893 and 89 formed at 1,892 and 1,892 respectively
4 is inserted. Of these printed wiring boards 891, 892, rotor magnets 31,
FG patterns 51 and 5 are on one side facing 32.
2 are formed, and stator cores 41,... are formed on the other side.
..., 41 and 42, ..., 42 are arranged, respectively. Here, the capstan motor 43 consisting of the rotor magnet 31 and the printed wiring board 891 and the reel motor 44 consisting of the rotor magnet 32 and the printed wiring board 892 are the motors 43 , 44.
The recesses 901 and 90 of the magnetic shielding member 90 have recesses 901 and 902 that can accommodate the recesses 901 and 902, respectively.
It is housed within 2. Both ends of this magnetic shielding member 90 are fixed to the substrate 36 by screws 911, 911 and nuts 912, 912. Note that in the recesses 901 and 902 of the magnetic shielding member 90, printed wiring boards 891 and
892 support portions 903 and 904 are formed, respectively. Further, the rotation shafts 31 of the rotor magnets 31 and 32 are provided on the bottom surfaces of the recesses 901 and 902.
Bearing 90 that supports the lower end in the figure of 1,321
5 and 906 are attached, and the magnetic shield member 90 serves to magnetically shield between the capstan motor 43 and the reel motor 44 , and also serves to support the rotor magnets 31 and 32. Furthermore, what is shown in FIG. 19b is a configuration in which the recesses 901 and 902 of the magnetic shielding member 90 are separated, and the capstan motor 43 and the reel motor 44 are covered with independent magnetic shielding members 907 and 908, respectively. , each magnetic shield member 907, 908 with screws 913, 9, respectively.
13 and 914,914 and Natsuto 915,915
and 916, 916, and are fixed to the substrate 36. Next, as shown in FIG. 20a, the printed wiring board 3
3 stator cores 41,..., 41 and 42,
..., 42 and the corresponding portions have through holes 33.
3,..., 333 and 334,..., 334 are formed, and the through holes 333,..., 333 and 334,
..., 334, each stator core 41,
..., 41 and 42, ..., 42 may be fitted. In this way, each stator core 41,..., 41 and 42,...
The thickness of the stator cores 41,..., 42 is substantially reduced by the thickness of the printed wiring board 33, which is suitable for downsizing, and the stator cores 41,..., 41 and
2, . Furthermore, as shown in FIG. 20b, the number of coil turns of the stator cores 41 , . . . , 41 and 42, . , the overall size remains unchanged from that previously shown in FIG. 18a. In other words, it is possible to increase the rotational torque by the same amount. Furthermore, as shown in FIGS. 20c and 21, a substrate 92 made of a synthetic resin material is brought into close contact with the lower surface of the printed wiring board 33 in the drawings. This board 92
Bearing recesses 921, 922, 923 are formed at positions corresponding to the rotating shafts 311, 321, 541 of the rotor magnets 31, 32, 54, and each stator core 41, . . . , 41, 4
Recesses 924, ..., 924, 9 are provided at positions corresponding to 2, ..., 42 and 49, ..., 49, respectively.
25, . . . , 925 and 926, . . . , 926 are formed. Then, with the printed wiring board 33 and the substrate 92 in close contact, each rotor magnet 31, 32, 5
The rotating shafts 311, 321, 541 of 4 are inserted through the through holes 335, 336 of the printed wiring board 33 and supported by the bearing recesses 921 to 923 of the board 92, respectively, and the rotating shafts 311, 321, 541 of the stator cores 41, .
1, 42, ..., 42 and 49, ..., 49 are recessed portions 924, ..., 924, 925, ..., 925
and 926, . . . , 926, respectively. According to this configuration, since the bearing recesses 921 to 923 are formed in the substrate 92, there is no need to attach bearings to the printed wiring board 33. In other words, the weight of the rotor magnets 31, 32, 54 is reduced. Since the printed wiring board 33 can be received by the substrate 96 instead of the printed wiring board 33, the thickness of the printed wiring board 33 can be reduced. In addition, the printed wiring board 33 has a substrate 9
2 are in close contact with each other, the printed wiring board 33 can be reinforced. Next, as shown in FIG. 22a, the printed wiring board 3
3 may be attached to the substrate 36. That is, as previously explained in FIG. 20, the stator cores 41, . . . , 41 and 42, .
33 and 334, . And rotor magnet 3
The upper part of each rotating shaft 311, 321 of No. 1, 32 in the figure is a through hole 337, 3 formed in the printed wiring board 33.
38 and bearings 931, 9 attached to the substrate 36
32 respectively, and protrude upward from the board 36 in the figure. In addition, the rotor magnets 31 and 32
The lower ends of the rotating shafts 311, 321 in the figure are fitted with screws 917, 917 and nuts 918, 91 in the shape shown in the figure.
8 and is rotatably supported by a receiving member 94 fixed to the substrate 36. According to this configuration, the printed wiring board 33 and the receiving members 94 that support the rotor magnets 31 and 32 are all attached to the board 36, so that the members that support the printed wiring board 33, the receiving members 94, etc.
There is no need to provide it separately in a cabinet (not shown) of the tape recorder, which greatly simplifies the configuration and facilitates miniaturization. Furthermore, when the operating parts (not shown) of the tape recorder and the like are assembled on the board 36, the capstan motor 43 and the reel motor 44 can be assembled at the same time, which is very convenient for assembly work. Furthermore, as shown in FIG. 22b, a printed wiring board 33 may be used for directly placing the tape in place of the substrate 36. In this case, for example, the head chassis 47
Various pins 96, . ,…
..., 96 as shown in FIG. 23, the runner 97,
. . , 97, it is convenient and the printed wiring board 33 can be reinforced. Furthermore, when a printed wiring board 33 is used in place of the substrate 36, as shown in FIG. A capstan motor 43 and a reel motor 44 ,
The magnetic tape and the recording/reproducing head 46 can be magnetically shielded. Here, what is shown in FIG. 24b shows an example using two printed wiring boards. That is,
At the bottom of the figure of the rotor magnets 31, 32, stator cores 41,..., 41 and 42,..., 4 are shown.
A printed wiring board 33 is provided with FG patterns 51 and 52. This printed wiring board 33
is installed on the bottom surface of the receiving member 99 formed in a substantially concave shape. The receiving member 99 is fixed at both ends to another printed wiring board 100 provided in place of the substrate 36 with screws 101, 101 and nuts 102, 102. Here, the rotating shafts 311, 32 of the rotor magnets 31, 32
The lower end of FIG. 1 is a bearing 10 attached to the printed wiring board 33 and the bottom of the receiving member 99 as shown.
3 and 103, respectively, and are rotatably supported. Further, the upper portions of the rotating shafts 311, 321 of the rotor magnets 31, 32 in the drawing are connected to the printed wiring board 1.
The bearings 104, 104 attached to the printed wiring board 100 are respectively inserted therethrough and protrude upward in the drawing of the printed wiring board 100. In this way, even if the configuration includes two printed wiring boards 33 and 100, by attaching the magnetic shielding member 105 to the lower surface of the printed wiring board 100, for example, the capstan motor 43 and the reel The motor 44 and the magnetic tape and recording/playback head 46 can be magnetically shielded. Next, as previously shown in FIG. 22b, the substrate 3
When a printed wiring board 33 is provided in place of 6, as shown in FIG.
For example, a power switch 106, an operator 10 for setting the tape type (normal, chrome, metal, etc.)
7, 107, 107 and its display section 108, 10
8, 108, various operation sections and display sections such as a noise reduction (NR) processing setting operation element 109 and its display section 110, and a tape running state display section 111 can be formed. Here, as the display section 111 for the tape running state, for example, an appropriate color is formed between the reels 40 and 55 of the printed wiring board 33 by silk printing or the like, and the reel 4
As the tape is wound around 0 and 55, this display portion 111 is sequentially covered by the tape from the end, thereby displaying the tape display amount. In addition to this, the display section 111 includes:
As shown in FIGS. 26a and 26b, both reels 40 and 5
Multiple LEDs 112, ..., 112, 1 between 5
13, ..., 113 are arranged, reels 40, 55
As the tape is wound around the LED
112,...,112 and 113,...,113
Alternatively, the lights may be lit sequentially from the end. Then, as mentioned above, the capstan motor 4
3 and the reel motors 44 and 56 , a printed wiring board 33 is provided with various operation parts and display parts.
For example, as shown in FIG. 27, this is incorporated into a cassette tape deck or the like. That is,
Front panel 1111 of this cassette tape deck
A printed wiring board 33 is installed so as to be substantially parallel to the front panel 1111, and a cassette lid made of a transparent material is provided on the front panel 1111 so that the reels 40, 55 and the display section 111 can be seen from the outside. 111
2 is provided, as well as a power switch 106, setting operators 107, 109, and a display section 10 thereof.
A through hole, a display window, etc. (not shown) are formed so that the parts 8 and 110 can be operated and confirmed from the outside. Furthermore, on the front panel 1111, there are an operation section 1113 for setting the cassette tape deck in a predetermined operating state and a stopped state, a VU/peak level meter 1114, and a recording level adjustment dial 11.
15, playback output level adjustment dial 1116,
A headphone jack 1117, an external microphone jack 1118, and the like are provided. Therefore, as described above, the capstan motor 43 and the reel motor 4 are connected to the printed wiring board 33.
4 and 56 as well as various operating sections and display sections, the configuration can be simplified and downsized, and processing operations such as half-mounting of the printed wiring board 33 can be performed all at once. It can be easily manufactured.
Further, as shown in FIG. 27, the printed wiring board 33
It is possible to incorporate the various operating sections and display sections into the front panel 1111 at the same time as incorporating it into a cassette tape deck or the like, and in this respect as well, the ease of assembly can be improved. Further, the operation section 1113, the VU/peak level meter 1114, the recording level adjustment dial 1115, and the playback output level adjustment dial 111
6. The headphone jack 1117 and the external microphone jack 1118 are also attached to the printed wiring board 3.
3, the assembly work can be made even easier. In addition, at least the front panel 1111 of the printed wiring board 33
For example, a solder resist or the like may be applied to the portion visible from the outside so as not to spoil the aesthetic appearance. Furthermore, the display section 111 for the tape running state
As, LED112,...,112 and 11
3, . . . , 113, for example, a liquid crystal display or the like may be used. In addition to providing various operating units and display units on the printed wiring board 33, as shown in FIGS.
and each stator core 41,..., 41, 42,...
..., 42, 49, ..., 49 and 59, ..., 5
9 (the one shown in FIG. 28 is a dual capstan type) control circuit section 1120 or the like may be provided. Next, as shown in FIGS. 29a and 29b, parts of the rotor magnets 31 and 32 of the capstan motor 43 and the reel motor 44 may be provided so as to overlap (wrap) each other. be. That is, both rotor magnets 3
1 and 32 are shown in figure b when viewed from above in figure 29.
As shown in the figure, they are installed so that they partially overlap each other. And each rotor magnet 3
Between 1 and 32 are printed wiring boards 1121 and 1122.
are arranged side by side. This printed wiring board 1121 has stator cores 42, .
2 is formed. In addition, the printed wiring board 11
22, stator cores 41, . . . , 41 and an FG pattern 51 are formed in a portion facing the rotor magnet 31. Then, the rotating shaft 311 of the rotor magnet 31
The lower end in the figure is the printed wiring board 1121, 11
It is rotatably supported by a bearing 1124 attached to a substrate 1123 installed substantially parallel to 22. Further, the rotating shaft 3 of the rotor magnet 31
The upper part of the figure 11 shows printed wiring boards 1122, 112.
1 through the through holes 1126, 1125 formed in the printed wiring boards 1121, 1122, and a bearing 1128 attached to the board 1127 installed approximately parallel to the printed wiring boards 1121, 1122, and protrudes upward in the board 1127 in FIG. 29a. has been done. Furthermore, the rotating shaft 3 of the rotor magnet 32
The lower part of the figure 21 shows printed wiring boards 1121, 112.
The bearing 113 is attached to the substrate 1123 by passing through the two through holes 1129 and 1130, respectively.
1 is rotatably supported. Further, the upper part of the rotating shaft 321 of the rotor magnet 32 in the figure passes through a bearing 1132 attached to the base plate 1127, and projects upwardly in the figure of the base plate 1127. Therefore, as mentioned above, the rotor magnet 3
By arranging parts of 1 and 32 to overlap each other, the rotor magnets 31 and
32 diameter can be increased, the moment of inertia of the rotor magnets 31 and 32 can be increased,
This makes it possible to substantially improve rotational torque. This is especially effective when the positions of the capstan 39 and the reel 40 are predetermined, such as in a cassette tape recorder. Further, as shown in FIG. 30a, a portion of each rotor magnet 32, 54 of the reel motors 44 , 56 may be overlapped with each other. That is, printed wiring boards 1133 and 1134 are arranged in parallel between the rotor magnets 32 and 54, which are installed so as to partially overlap each other. This printed wiring board 1133 has stator cores 49, . . . , 49 in a portion facing the rotor magnet 54.
and FG pattern 53 are formed. Also,
The printed wiring board 1134 has stator cores 42,...
..., 42 and an FG pattern 52 are formed. Then, the rotating shaft 321 of the rotor magnet 32
The lower end in the figure is the printed wiring board 1133, 11
It is rotatably supported by a bearing 1136 attached to a substrate 1135 installed substantially parallel to 34. Further, the rotation shaft 3 of the rotor magnet 32
The upper part of the figure 21 shows printed wiring boards 1134, 113.
3, and a bearing 1140 attached to a substrate 1139 installed substantially parallel to the printed wiring boards 1133, 1134, and protrudes upward in the figure of the substrate 1139. . Furthermore, the rotating shaft 5 of the rotor magnet 54
The lower part of the figure 41 shows printed wiring boards 1133, 113.
The bearing 114 is attached to the substrate 1135 by passing through the through holes 1141 and 1142 of No. 4, respectively.
3 is rotatably supported. Further, the upper portion of the rotating shaft 541 of the rotor magnet 54 in the drawing passes through a bearing 1144 attached to the substrate 1139, and projects upwardly in the drawing of the substrate 1139. Even with such a configuration, the reels 40 and 55
It is possible to increase the rotational torque without changing the interval between the two, and is particularly suitable for cassette tape recorders and the like. By combining the configurations shown in FIGS. 29a and 30a, the motor magnet 32 of the reel motor 44 can be assembled as shown in FIG. 30b.
It is also possible to partially overlap the rotor magnet 31 of the capstan motor 43 and the rotor magnet 54 of the reel motor 56 , respectively. Further, as shown in FIG. 31a, printed wiring board 1
Between 133 and 1134, magnetic shielding member 114
If 5 is interposed, the reel motor 4
4 and 56 can be magnetically shielded. Further, in FIG. 29a, printed wiring board 1121,
Even if a magnetic shielding member (not shown) is interposed between the capstan motor 43 and the reel motor 44, the capstan motor 43 and the reel motor 44 can be magnetically shielded. Here, what is shown in FIG. 31b is
In the configuration shown in Figure a, printed wiring board 112
1 and 1122 are removed, and the substrates 1127 and 1123 are removed.
Printed wiring boards 1146, 1147 are installed in place of the printed wiring boards 1146, 1147, and each stator core 42,..., 42, 41,..., 41 and
FG patterns 52 and 51 are formed respectively. And, by the magnetic shielding members 1148 and 1149 formed in a substantially box shape,
Rotor magnet 31 and stator core 41,...
By covering the rotor magnets 32 and stator cores 42, . . . , 41, respectively, the capstan motor 43 and the reel motor 44 can be magnetically shielded. This also means that the reel motors 44 , 5
It can also be applied to magnetic shielding between 6 and 6. Note that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without departing from the gist thereof. Therefore, as detailed above, according to the present invention, it is possible to prevent the leakage magnetic field from the motor from having an adverse effect on the magnetic tape, magnetic head, etc., and it is possible to contribute to reduction in size and weight with a simple configuration. An extremely good magnetic shielding device for a tape recorder can be provided.

[Brief explanation of the drawing]

Figures 1 a to c are configuration diagrams showing the types of tape drive mechanisms, Figures 2 a and b, and Figures 3 a and b.
are explanatory diagrams showing the principle of a direct drive type motor, and Figures 4 to 7 are respectively 1
A side sectional view, a top view, a perspective view, and a plan view showing a configuration in which a capstan motor and a reel motor are assembled on a printed wiring board, and FIG. A top view showing the incorporation of the capstan motor and reel motor, Figure 9 is a block diagram showing rotation speed control using the FG signal from the capstan motor, and Figure 10 shows the connection from the reel motor.
A block configuration diagram showing the tape running amount display and mode switching by the FG signal. Figures 11a and 11b are a top view and side view respectively showing the detailed configuration of the bearings of the capstan motor and reel motor incorporated in the printed wiring board. Cross-sectional views, FIGS. 12a to 12c and FIG. 13 are configuration diagrams showing bearing structures in dual capstan type and center capstan type tape recorders, respectively, and FIGS. 14a and b are diagrams showing the tape recorder according to the present invention. 15 and 16 are side sectional views showing an embodiment of the magnetic shielding device for the capstan, respectively, showing a structure for magnetically shielding the capstan motor and reel motor, and the magnetic tape and recording/playback head. FIG. 17 is a side sectional view and top view showing a configuration for magnetically shielding between the motor and reel motor; FIG. 17 is a top view showing a magnetic shielding structure between each motor in a dual-capstan type tape recorder; FIG. a to c and Figure 19 a, b
20A to 21C are side sectional views showing a modified example of a configuration for magnetically shielding between a capstan motor and a reel motor, respectively, and FIGS. 20a to 21C are respectively views in which the stator core of the motor is provided by penetrating the printed wiring board. FIGS. 22A and 22B are a side sectional view and a perspective view showing the configuration, respectively. The figure is a top view showing the printed wiring board shown in Fig. 22b with various guide pins etc. formed as outserts, and Figs. 24a and 24b respectively show the case where a printed wiring board is provided in place of the above board. 25, a side sectional view showing a configuration for magnetically shielding a capstan motor, a reel motor, a magnetic tape, and a recording/reproducing head;
The figure is a plan view showing a configuration in which various operating units and display units are incorporated into a printed wiring board in which a capstan motor and a reel motor are incorporated, and Figures 26a and 26b each show details of the display unit in the tape running state. 27 is a front view showing the printed wiring board shown in FIG. 25 assembled into a cassette tape deck;
FIGS. 28a and 28b are a top view and a side sectional view respectively showing a state in which a predetermined signal processing circuit section of a tape recorder and a control circuit section of a stator core are provided on a printed wiring board in which a capstan motor and a reel motor are incorporated. , FIGS. 29a and 29b are a side sectional view and a top view showing a configuration in which rotor magnets of a capstan motor and a reel motor are partially overlapped, respectively, and FIGS. 30a and 30b are a capstan motor and a reel motor, respectively. A side sectional view and a top view showing a configuration in which the rotor magnets of the motor and two reel motors are partially overlapped, and FIGS. FIG. 3 is a side sectional view showing a configuration in which a capstan motor and a reel motor are magnetically shielded from each other in the configuration. 11, 12...Reel stand, 13...Tape, 1
4, 15... Guide roller, 16... Flywheel, 17... Capstan, 18... Pinch roller, 19... Flywheel, 20... Capstan, 21... Pinch roller, 22... Rotor magnet, 23 ...Printed wiring board, 24... Bearing, 25... Substrate, 26... Bearing, 271 to 274... Stator core, 31, 32... Rotor magnet, 33... Printed wiring board, 34, 35...
... bearing, 36 ... board, 37, 38 ... bearing, 39 ... capstan, 40 ... reel, 4
1, 42...Stator core, 43 ...Capstan motor, 44 ...Reel motor, 45...
Tape cassette, 46...Recording/playback head, 47
...Head chassis, 48...Connector, 49...
... Stator core, 50 ... Bearing, 51 to 53
...FG pattern, 54...rotor magnet,
55... Reel, 56 ... Reel motor, 57
...Magnetic pole part, 58...Magnetic pole part, 59...Stator core, 60...FG pattern, 61...Bearing,
62...Amplification circuit, 63...φ-V conversion circuit, 6
4...F-V conversion circuit, 65... Reference oscillation circuit,
66... Frequency dividing circuit, 67... Reference voltage generation circuit,
68...Comparison circuit, 69...Amplification circuit, 70...
Drive circuit, 71... Counter circuit, 72... Display circuit, 73... Counter circuit, 74... Drive mechanism, 75... LSI, 761, 762... Connection terminal, 771, 772... Drive circuit, 78... ... Counter circuit, 79 ... Display circuit, 80 ... Detection circuit, 81 ... Mode switching mechanism, 821 to 827
...Runner, 83 to 88...Magnetic shielding member, 891,892...Printed wiring board, 90...Magnetic shielding member, 911...Screw, 912...Nut, 92...Substrate, 931,932...Bearing , 94...Receiving member, 95...Movable member, 96
... Pin, 97 ... Runner, 98 ... Magnetic shielding member, 99 ... Reception member, 100 ... Printed wiring board, 101 ... Screw, 102 ... Nut, 10
3,104...bearing, 105...magnetic shielding member, 106...power switch, 107...setting operator, 108...display section, 109...setting operator, 110,111...display section, 112,1
13...LED, 1111...Front panel, 11
12...Cassette lid, 1113...Operation unit, 11
14...VU and peak level meter, 1115...
... Dial for adjusting recording level, 1116 ... Dial for adjusting playback output level, 1117 ... Jack for headphone, 1118 ... Jack for external microphone, 1119 ... Signal processing circuit section, 11
20...Control circuit section, 1121, 1122...Printed wiring board, 1123...Substrate, 1124...Bearing, 1125, 1126...Through hole, 1127...
Board, 1128...Bearing, 1129, 1130
...Through hole, 1131, 1132...Bearing, 11
33,1134...Printed wiring board, 1135...Substrate, 1136...Bearing, 1137,1138...
...Through hole, 1139...Substrate, 1140...Bearing, 1141, 1142...Through hole, 1143,1
144...Bearing, 1145...Magnetic shielding member, 1146, 1147...Printed wiring board, 114
8,1149...Magnetic shielding member.

Claims (1)

[Claims] 1. A substrate formed of a synthetic resin material, a magnetic head supported on one side of the substrate and capable of approaching and separating from the magnetic tape, a rotating magnet disposed on the other side of the substrate, and a rotating magnetic field applied to the rotating magnet. a motor that includes a fixed coil that drives the magnetic tape with a rotating shaft of the rotating magnet; and a magnetic shielding member that is provided on the substrate and magnetically shields the rotating magnet and fixed coil, and the magnetic tape and magnetic head. A magnetic shielding device for a tape recorder, comprising: