JPS62281113A - Rotary head device - Google Patents

Abstract

PURPOSE:To make a device into miniaturization, lightening, compactness, and high efficiency, by providing another motor that is rotated and driven independently on the same axis of a rotary body structure driving motor, and constituting a pair-shaped rotator structure sandwiching a stator coil between either motor at least out of plural motors, constituting it as an electromagnetic part. CONSTITUTION:The titled device is structured in such a way that a capstan axis driving motor, etc., is also arranged along with a head driving DD motor on the same axis, and a multifunctional driving can be performed under a miniaturized, light, and compact constitution. Especially, a center axis 1 is fixed on the bottom plane part of a guide drum 3 directly, or indirectly, and at the upper part, a head rotary body structure of housing rotary type is engaged, and the lower part is structured to engage a driving rotary part of the same type for a capstan axis, etc., thereby, the constitution of plural motors can be facilitated. Furthermore, at least either out of the plural motors whose rotator is formed in the pair-shaped structure, makes a rotator magnet 18, and a rotary yoke 19 in one body sandwiching the stator coil, or the first rotator magnet, and the second rotator magnet are linked opposing thier magnet poles with each other, thereby, it is possible to remarkably reduce a load, core loss, and a cogging force applied on a bearing.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the structure of a rotary head device for a VTR or digital audio tape recorder (NIR), and in particular, it is small, compact, low cost, and provides multifunctionality and high performance. Regarding structure.

[Conventional technology]

Conventional devices have a structure that has a single rotating part that only has a head rotation function, as shown in the patent publication No. 53-55007, and there is no other example of a structure that has a rotation operation function. An example of the structure of a motor that obtains a plurality of rotating powers from the same axis, although the purposes are different, is the structure described in Japanese Patent Publication No. 110574/1982. The purpose of this example is to simultaneously drive a capstan and a reel shaft for a VTR. 2 The basic configuration of the part that obtains power is as follows. That is, it has a first rotary output shaft to which a first rotor is fixed on the same axis and a second rotary output shaft to which a second rotor is fixed, and the first rotor is fixed to a corresponding motor. The second rotor is rotated by supplying power to the rotor, and the second rotor, which is electromagnetically coupled to the rotor, is also rotated accordingly. Therefore, this structure is configured to obtain both the first and second rotating shaft outputs from the rotational force of the first motor rotor, and it is not possible to obtain each output separately. Further, since two combined bodies each consisting of one rotor and one rotating shaft are provided as a unit rotating structure as a rotating part, it is difficult to improve assembly precision such as concentricity between each rotating combined body. Further, the loss in the electromagnetic coupling portion is considered to be particularly large, and the power consumption of the motor for generating the first rotor power increases. Furthermore, the second rotor has poor speed controllability and is difficult to rotate at a constant speed.

The motor scale also tends to be large, and there is a limit to miniaturization.

Even when this prior art structure is used in a rotary head device, there are problems similar to those described above.

[Problem that the invention seeks to solve]

The above conventional technology has a configuration in which a first rotational output is obtained from the rotational force of one motor, and a second rotational output is obtained using a coupling. High controllability, high precision assembly, small size and weight, high efficiency, etc. are not considered, and it is impossible to significantly improve these points with this structure.

An object of the present invention is to improve the above-mentioned drawbacks of the prior art, and to provide a rotary head device that is small, lightweight, and highly efficient, and has a multi-axis output function that can independently perform rotational operations other than the head rotational operation. be.

[Means for solving problems]

In order to achieve the above object, the rotary head device of the present invention has a structure in which a capstan shaft drive motor, etc. is also installed on the same axis as the head drive DD motor, allowing multi-functional drive in a small, lightweight, and compact device configuration. It is characterized by points. %, the central shaft is directly or indirectly fixed to the bottom of the guide drum, the upper part is engaged with a rotating housing type head rotating structure, and the lower part is engaged with a driving rotating part such as a capstan shaft of the same shape. This makes it easy to realize the multiple motor configuration described above. Furthermore, at least one of the motors has a rotor having a pair-like structure, and a rotor magnet and a rotating yoke are integrated with a stator coil sandwiched therebetween, or the first rotor magnet and the second rotor magnet are mutually polarized. The bearings are arranged facing each other in a row, so that the load on the bearing, iron loss, and cogging force can be significantly reduced.

[Effect]

(IJ) With a structure in which multiple motors are arranged concentrically on the central axis, it is easy to easily take out separate shaft outputs independently from the same axis, and control is also easy.The overall size, including the drive load, can be significantly reduced. Since the structure shares the same structure, the number of parts can be reduced and it is easy to integrate, resulting in low costs.

(2) Since the center shaft is fixed to the lower guide drum, the upper tram can be fixed to the tip of the center shaft, and the rotating section can be built in or sandwiched between the upper and lower drums. This structure can significantly improve the head touchability with respect to recording media such as tape, motor load, disturbance, etc. compared to conventional upper drum rotating structures.

(3) If the motor section is constructed with a paired rotor sandwiched between air-core stator coils, no iron loss or cogging torque will occur within the stator even when the rotor magnet rotates. Also, the magnet suction force does not act on the bearing. Therefore, the motor can have low power consumption, low uneven rotation, and long life.

〔Example〕

The present invention will be explained below based on examples.

FIG. 1 is a diagram showing a first embodiment of the rotary head device of the present invention, in which V
This is an example of the structure of a rotating head device for TR. This embodiment has a fixed-shaft middle drum rotating structure, in which the center shaft 1 is fixed by press-fitting into the bottom of the lower drum 3, and the upper drum 2 is not rotated, but a second shaft is provided at the bottom of the upper drum 2. It has a structure that rotates the drum.

A flat first drive motor built inside the lower tram 3 rotates a rotating section including a disk on which a head (video head) 8 is mounted, and a second motor is similar to the first motor. A flat motor is provided concentrically around a central shaft 1 that is located on the lower surface of the bottom of the lower drum 3 and protrudes through the lower surface, and in this example, it drives a capstan shaft. The upper drum 2 has a fixed disk 1 at the top end of the central shaft 1.
It is indirectly fixed via o. The head 8 is fixed to the outer periphery of a head identification disk 78, and the disk 78 is fixed to the outer periphery of the rotating structure 4 via a magnetic fixed disk 75. The rotating structure 4 is provided with bearings 5α and 5b such as ball bearings at two locations above and below the center thereof, and is rotatably engaged with the central fixed shaft 1.

The rotating side yoke 15 of a flat rotary transformer is fixed to the upper surface of the head fixing disk 78, and the rotor of the first motor (
(composed of a rotor magnet 18 and a rotor yoke 19)
It is fixed. A fixed side yoke 14 of the rotary transformer is fixed to the lower surface of a fixed disk 10 at the upper end of the shaft 1. The electromagnetic part of the first motor includes a rotor magnet 181, a rotating yoke 22. The rotating yoke 22 is fixed to the lower end of the rotating structure 4, sandwiching the stator coil 21 therebetween. The stator coil 21 is formed into a highly rigid flat shape, and its outer peripheral edge is fixed to the inner peripheral edge of the lower drum 6 with screws 12 or the like. The stator coil 21 contains iron.

It has an air-core configuration that does not contain any magnetic material such as ferrite.

A multi-pole magnet 51 for FG (frequency generator) is fixed to the lower surface of the rotating yoke 22, and is opposed to the FG board 29 provided on the bottom surface of the lower drum 3 with a small gear knob in between. Further, a tack magnet 42 for generating a position signal of the head 8 is fixed to the lower surface of the rotating yoke 22, and a tack magnet 42 for generating a position signal of the head 8 is fixed to
A tack sensor 41 is fixed on top of the tack sensor 9. A second motor is provided at the bottom of the bottom of the lower drum 3, with its rotating portion engaged with its central fixed shaft. The second motor also
The electromagnetic part configuration is similar to that of the motor, and the air-core stator coil 2
1' is sandwiched between the rotor magnet 18' and the rotating yoke 22.
′ are paired to form a rotating body. The rotating structure 4' has bearings 5c and 5d at its center, and a pulley 11 for power transmission via a belt at its lower end. 6 and 6' are preload pieces for applying preload to the bearings 5α, 5A, 5c, and 5cL. Substrate 28 fixed on head fixing disk 78
is for connecting the terminal of the head 8 and the winding terminal of the rotary transformer 15.

Also, a substrate 2 provided on the fixed side yoke 14 of the rotary transformer
Reference numeral 4 is for connecting the winding terminal of the rotary transformer 14 and the head signal processing circuit. As the signal processing circuit, a signal amplification circuit IC101 (reproducing system) 102 (recording system) and other post-processing circuit IC106 are installed.

The signal circuit mounting structure reduces disturbances and significantly improves signal S/N. 60 is a lead bin for connecting the terminal of the stator coil 21 to a wiring board 30 provided outside the drum. a terminal of the stator coil 21' of the second motor;
Sensor terminals and the like are also connected on the surface of the substrate 30. Stator coil: N, 21 by external servo electronic circuit
' Controlly supplies power to the motors and rotates the rotor of each motor at a predetermined rotation speed and torque. The first motor is a so-called drum motor, which rotates a head fixed to the rotor via a disk 75, 78 directly connected to the rotor at a predetermined constant speed.

The rotational speed signal is obtained from a back electromotive force frequency signal generated in the radial conductor pattern on the FG substrate by the FG magnet. The rotational position of the head 8 is detected by a voltage signal generated in the tack sensor 41 by the magnetic field of the tack magnet 42. The FG double signal rotation speed is feedback-controlled, and the rotation phase is controlled by the tack signal. The head 8 has its tip protruding by a small amount from the flat side surface of the upper drum 2 and lower drum 3, and scans the tape surface running diagonally on the side surface by lightly sliding it to record or record a video signal. It's meant to be played. In this embodiment, the second motor provided on the lower surface of the lower drum is a capstan motor, and a capstan shaft provided elsewhere is decelerated and driven by a belt 150 to drive the tape to run at a predetermined speed.

The FG of the second motor is provided in the stator coil 21'. According to the rotary head device of this embodiment structure in which the motor is also controlled at a constant speed by the FG and the phase is controlled based on a signal from a separately provided oscillator, etc. Since a head rotation motor and a capstan drive motor are provided, a small, lightweight and compact VTR can be constructed.

(2) Since the central axis is fixed, there is less need to take pictures when the motor rotates. Furthermore, since one shaft is used, it is easy to assemble the first and second motors and each rotating part with high precision. Especially the first one. The second independent rotary motors can easily be arranged in close proximity.

Each motor has high rotational stability with no torsional vibration of the shaft.

Since the number of parts including the load system driven by the f3+second motor and the number of assembly steps can be reduced, this can be manufactured at low cost.

(4) Compared to the conventional structure in which the second motor is provided separately in other parts, in the structure of this embodiment, the second motor is provided on the lower surface of the lower drum, so that the mounting strength and precision can be extremely high. This point is particularly advantageous in the case of a structure built into a thin-walled chassis.

+51 Since multiple main motors of a VTR can be housed in a small space within the same location, magnetic leakage caused by these motors can be easily shielded and lowered.

(6) Because the rotating parts are placed close together on the same axis that shares a fixed part, there is no need to replace jigs, reinstall, or replace the testing machine during dynamic balance testing of each rotating part. Therefore, efficient work is possible.

(7) Since a rotor is used in which an air-core stator coil is sandwiched between a magnet and a rotor, no iron loss or cogging torque is generated within the stator due to the magnetic field of the magnet during rotation. Therefore, the efficiency of the motor can be increased. Further, the magnetic attraction force only acts between the rotary yokes 22 and 22' and does not act between them and the stator. As a result, the load on the bearing, including the preload load, can be reduced, thereby significantly reducing bearing friction and reducing disturbance vibrations generated from the bearing. Furthermore, the life of the bearing can be extended. These effects are particularly noticeable when rotating at high speed.

(8) When the second motor decelerates and rotates the load rotating body connected to it at a constant speed, the second motor (capstan motor) rotates at high speed, so the FG can be set at a low rate and with high accuracy, and the load rotation Since the rotational inertia converted to the body axis (capstan axis) can be significantly increased, the performance of the servo system can be improved and low rotational unevenness can be reduced. Therefore, a high-performance VTR with low jitter and low wow/flutter can be realized.

(9) Since the head rotating body is housed in a semi-closed manner within the space formed between the upper drum and the lower drum, noise during rotation can be masked and significantly reduced. Furthermore, since the surface area of the rotating parts can be reduced, air friction can be reduced, and noise (wind noise) and loss (windage damage) caused by this can also be reduced.

α1 Since the rotating part driven by the first motor (drum drive motor) can be made small, lightweight, and low inertia, the amount of dynamic unbalance of the rotating part can be reduced and the vibrations caused by this can be reduced. In addition, the start-up time can be shortened.

Since the θυ bearing is not directly connected to the lower drum, the vibration of the lower tram is reduced to a low level.

Since the distance between the bearings can be shortened, the entire device can be made thinner, and the preload applied to the bearings during assembly can be reduced, reducing bearing friction and lowering power consumption.

α3 Since the upper drum has a fixed structure, the disturbances such as vibrations that the upper drum gives to the running tape are extremely small.

Therefore, wow/flutter and jitter can be improved.

α4 Since the upper drum is fixed, it prevents the tape from floating up and down from the drum surface due to the rotation of the upper drum. Good head touch is obtained even under low head balance protrusion and low tape tension, resulting in stable high performance. You can get the head output.

In addition, damage to the tape surface and wear on the head can be improved. Furthermore, since there are few restrictions on the shape, size, and material of the surface of the upper drum, these processes can be easily performed and at low cost.

α9 Is there an upper drum support member such as a coupler on the side of the drum? - Since the structure can be made without cutting, the angle of tape winding can be easily increased, and therefore the drum diameter can be reduced and the device can be made more compact.

σe Since the upper drum is fixed, there are various advantages such as the ability to provide multi-functionality by providing a lead structure on the side surface of the upper drum to regulate the tape running posture, and attaching other structural pieces.

FIG. 2 is a diagram showing a second embodiment of the rotary head device of the present invention, in which rotary transformers 14 and 15 are provided on the inner bottom surface of the lower drum 3, and the rotary side yoke 15 is used as the rotary yoke of the motor to drive the motor magnetic circuit. It has a structure that also serves as a member. A tack magnet 42 is also fixed on the yoke surface. A thin wiring board 25.2 is attached to the stator coil 21.21'.
5' are pasted together, each coil terminal and sensor 40,
4i, 40' terminals, etc. are wired. Rotating transformer 1
5, the coil end unwired substrates 2a, 2a' are the lower drum 3.
The signal amplification circuits IC101, 102, the post-processing circuit IC103, etc. are also provided on the lower part of the iron substrate 2 as in the first embodiment.
4' above. FIG. 2A shows a configuration example in which a magnetic material plate 61 such as a thin iron plate is provided on the back surface of the rotary transformer 15 to form a magnetic circuit with the first rotor magnet 18. By providing the magnetic material plate 61, the wall thickness and outer diameter of the rotary transformer 15 can be reduced, and it is possible to prevent the rotor magnet magnetic field from being mixed into the transformer coil signal as a disturbance.

According to the structure of the second embodiment having the configurations shown in FIG. .

(2) Since the rotating transformers i4 and 15 are provided inside the lower drum s, the rotating part can have a low center of gravity structure. Therefore, rotational stability can be improved. In addition, since the weight of the parts fixed to the upper end of the shaft 1 can be reduced, the weight of the parts fixed to the upper end of the shaft 1 can be reduced. The resonance frequency of the fixed support system of the upper drum 2 can be increased and the disturbance resistance can be improved.

(3) Rotating transformer 1! , 15 are removed from the upper part of the head fixing disk 78, making it easy to attach and detach the head 8.

(4) Since the connection leads for the 9-rotation transformer signal system of the motor are both located at the bottom of the lower drum, there is a risk of bending load being applied to shaft 1 during handling and damage to the drum surface or head. You can get the effect of 2nd class with less.

FIG. 5 is a diagram showing a third embodiment of the rotary head device of the present invention, in which the rotating body is supported non-contact by using fluid dynamic pressure in place of the bearings 5α and 5b in the structures of the first and second embodiments. A side view of the structure using a pressure bearing, and Figure 4 is an enlarged view of the hydrodynamic bearing.
(α) is a plan view of the journal part, (A+ is a plan view of the thrust part. The configuration of the second motor provided at the lower end of the shaft 1 is as follows:
This is similar to the example.

The dynamic pressure bearing is constructed by forming dogleg-shaped shallow grooves (herringbone group) 200α, 200A, and 215 at two locations on the upper and lower sides of the outer peripheral surface of the fixed shaft 1 and on the upper surface of the thrust load receiving piece 210. A second rotating sleeve (hydrodynamic bearing sleeve) 170 is located at the center of the first rotating sleeve (rotating structure) 4.
is fixed, and the inner circumferential surface and lower end face thereof are opposed to each group part with a narrow gap between them.

Each narrow gap portion is filled with a lubricating fluid such as grease or oil, and the lubricating fluid is drawn into each group by rotation (counterclockwise rotation) of the dynamic pressure bearing spring 170.
Fluid dynamic pressure is generated in each portion to float the fluid dynamic pressure sleeve 170 in the radial direction and thrust direction. That is, in the journal section, groups 200α and 200b
Dynamic pressure is generated in the radial direction, and upward dynamic pressure in the axial direction is generated by the group 215 in the thrust portion. In this way, the bearing sleeve +70 is supported by the shaft 1 and the thrust load receiving piece 210 through the fluid in a non-contact state.

In this structural example, the thrust load receiving piece 210 is made of a material having a coefficient of linear expansion that corresponds to the temperature characteristics of the fluid viscosity, so that even if the fluid viscosity decreases due to temperature rise, the thrust dynamic pressure decreases, and the flying height decreases. The expansion of the receiving piece 210 compensates for the variation, keeping the height of the rotating body constant, and the magnetic head 8
This is so that the position of the camera can always be maintained at a predetermined position. Concave portions are provided in the upper, middle, and lower portions of the dynamic pressure bearing sleeve 170 so that fluid can be held therein. The structure in which the FG magnet 51 is provided on the lower surface of the yoke 22 is the same as in the first embodiment. A magnetic material plate 65 is provided below the FG board 29. By providing this magnetic material plate 65, a thrust attraction force is generated between it and the FG magnet 51 to pull the rotating part downward. As a result, even if the apparatus is placed on its side or upside down, the rotating part can always be maintained at a constant height, and in balance with the buoyancy force generated by the group 215, highly rigid non-contact thrust support can be achieved.

Further, F interlinking with the FG pattern on the FG board 65
Since the magnetic flux from the G magnet 51 can be increased, the FG signal output level can be improved. Further, since the uniformity of the magnetic flux distribution can be improved, the FG signal accuracy can be improved.

350 is a small hole for removing air from within the hydrodynamic bearing.

According to this structure using hydrodynamic bearings, compared to the structures of the first and second embodiments using conventional bearings such as ball bearings, the rotating part can be supported without contact with the fixed part, so vibrations during rotation can be significantly reduced. Can be reduced.

(2) Bearing...Using part (hydrodynamic bearing sleeve 17
Since the outer diameter of the 0° rotation sleeve 4) can be made smaller, the dimensions of the electromagnetic part of the motor can be increased and the performance of the motor can be improved.

(3) The life of the bearing can be extended.

(4) New effects such as the second one, which can reduce the cost of the bearing part, can be obtained.

FIG. 5 is a diagram showing a fourth embodiment of the rotary head device of the present invention, in which a first motor built in the lower drum 6 and a second motor provided at the outer lower part of the drum 3 are connected by two rotor magnets. magnets with the same number of magnetic poles (first rotor magnet 18
α and second rotor magnet) +8b, first rotor magnet 184' and second rotor magnet) +ab'
), and air-core stator coils 21 and 21' are arranged one above the other with opposite poles facing each other.

In the same figure, each magnet 18α, +8A, 48shi,
+8'7° is rotor yoke 19α, 19A, respectively.
+9- and +9'b, and are attached to the magnet fixing disk 75 and the lower surface of the rotating structure 4.

In the structure of this embodiment, each first rotor magnet 18ai8
Large dimensions with 'a as the main magnet, each second rotor magnet) +8b.

+8'b') Although the auxiliary magnet has a small size, it may have the same size or a reverse dimensional relationship.

Also, the materials of each magnet are 18α and +8.6.18λ.

Both 18'h may be the same or different ones may be combined.

According to the structure of this embodiment, (1) Since two rotor magnets with opposite polarities are used, the magnetic path length of the magnet magnetic circuit can be shortened, and low-energy, low-cost magnets such as thin magnets and ferrite can be used. A strong magnetic field can be easily obtained using this method. Therefore, it is possible to increase the motor constant value and improve the stability against load, and also realize cost reduction.

(2) Rotor magnets 18α, 18h and +8.
The attraction forces of ', +8'b do not act on the bearings 5, 5'.

Therefore, the load on the bearing can be reduced and friction torque can be significantly reduced.

Bearing preload loss does not occur.

(3) Since the uniformity of the magnetic field distribution between each two magnet poles can be increased, the amount of magnetic flux linkage with the stator coil can be increased, and the motor efficiency can be improved. Furthermore, it is possible to reduce the rate of deterioration of motor performance, such as an increase in torque ripple due to deviation in the fixing position of the stator coil within the gap. Therefore, installation work and accuracy control are easy.

(4) Since the permeance of the magnet magnetic circuit is high, there is extremely little magnetic leakage to the outside. Therefore, it is possible to reduce the noise caused by the rotating magnetic head, signal system circuit, etc.

(5) Between opposing magnets 18α and 18h or 1B≦, 18
By combining dimensions, materials, magnetic pole shapes, etc., the magnetic field distribution and magnetic flux amount can be changed to achieve high efficiency, low torque ripple, and low cost.

New effects such as

Fig. 6 shows a fifth embodiment of the present invention, which has a structure in which two flat motors (the upper side is called the second motor and the lower side is called the third motor) are directly connected to the lower part of the lower drum. . A first motor and a second motor that drive the head 8 DD are connected to the yoke 2.
2.22' configuration, the third motor is the yoke 2
It is a configuration that fixes #2. The second motor is a capstan shaft drive motor, and the fifth motor is a reel shaft drive motor.

According to this structure, three independent rotary powers can be easily obtained, so the power transmission mechanism can be simplified, and a set such as a VTR can be made smaller and lighter, and at the same time, it can achieve high performance with low disturbance. Also, unlike the first to fourth embodiments, the fixed disk 7-day disk has an outer diameter almost equal to that of the upper drum 2 and the lower drum, so that the tape running resistance on the drum surface is reduced and the first The motor can save power.

FIG. 7 shows a sixth embodiment of the apparatus of the present invention, in which a third motor is fixed to the upper part of the upper drum 2. The stator of the third motor is fixed to the upper surface of the upper drum 2. The structure of this embodiment also provides substantially the same effects as the fifth embodiment.

FIG. 8 shows a seventh embodiment of the apparatus of the present invention, in which a head 8 is fixed to the lower surface of an upper drum 2, and the upper drum 2 is rotated by a first motor. The central shaft 1 is fixed at the center of the bottom surface of the lower drum 3 as in the previous embodiments.

The first motor attached to the lower drum 3 and driving the head 8 in DD is configured to rotate the yoke 22, and the first motor is attached to the lower part of the lower drum 3 and drives the capstan shaft etc. via the belt 150. Motor No. 2 has a configuration using two magnets (18g, +86) with different polarities facing each other. 400 is a conductive material plate, and noise such as high frequency electric field in the external world is transferred to the rotating transformer +
4, 15 and their signal processing circuits/boards, and to prevent dirt and the like from entering the rotating transformer lis section. According to the structure of this embodiment,
Since the rotary transformers 14 and 15 are provided on the upper part of the upper drum 2, it is easy to assemble the transformers and perform adjustment work such as opening the gap. Furthermore, compared to the conventional shaft-rotating upper drum rotating structure, since the shaft is fixed, there is no torsional vibration of the shaft, resulting in low vibration. The effect of having a plurality of second motors coaxially provided is the same as in the previous embodiments.

In each of the above embodiments, flat brushless motors are combined as a plurality of motors.
The scope of the present invention is not limited to brushless motors, and may include combinations of motors of other types with brushless motors, or combinations of motors of completely different types. In the case of a brushless motor, a method that does not use sensors may also be used. Further, the shape is not limited to a flat shape, but may be a cylindrical shape or the like. There is also a structure in which a magnetic material is provided in a part of the stator coil section and the magnetic attraction force generated by the magnetic material is applied to the bearing. Furthermore, especially in a configuration in which two magnets (main magnet and auxiliary magnet) are used as a rotor with their magnetic poles facing each other, the combination of the opposite-polarity magnetic pole opposing structure and the air-core stator coil described in the example, and the configuration In addition, there are combination configurations of a different polarity magnetic pole facing structure and a stator coil that partially contains magnetic material, and a combination configuration of a same polarity magnetic pole facing structure and an air-core stator coil or a stator coil that has a magnetic material inside. Also within the scope of this invention.

〔Effect of the invention〕

According to the present invention, (1) the head rotation motor and the motor for driving other parts can be installed compactly on the head rotation center line;
A set such as R can be realized with a small size, light weight, and simple structure.

(2) In a structure in which the support shaft of the head rotating structure is fixed, the rotating part can be rotated with low vibration and high stability.

(31) This can be manufactured at low cost because the number of parts and manufacturing man-hours can be reduced, including the load system driven by the second motor section.

(4) Due to the structure in which the rotary support shafts are arranged on the same straight line, it is easy to assemble and it is easy to improve the assembly accuracy. Therefore, a high-performance device with low torque ripple can be constructed.

t5) It is easy to prevent multiple motors required to drive a set such as a VTR from collapsing into a small space within the same location.

(6) Dynamic balance testing of multiple rotating parts can be performed efficiently and easily. .

(7) When the second motor decelerates and drives a load rotating body connected to it by a belt or the like, the second motor must rotate at a high speed, so the FG can be made at a lower rate and with higher precision. Furthermore, since the inertia value converted to the axis of the load rotor can be greatly increased, servo performance can be improved, the load rotor can be rotated highly smoothly, and sets such as VTRs can be improved in performance.

(8) At least one of the motors arranged on the same axis is connected to a paired rotor consisting of an air-centered stator coil, a rotor magnet and a rotating yoke, or a first rotor magnet and a second rotor magnet. This structure eliminates iron loss and cogging torque within the stator during rotation,
It also prevents the bearing load from increasing due to the rotor magnet absorption force, making it possible to reduce the load. This allows the device to have high efficiency and low rotational unevenness.

FIG. 1 shows a first embodiment of the rotary head device of the present invention, and a second embodiment of the rotary head device of the present invention.
The figure is a diagram of the second embodiment of the same, Figure 3 is a diagram of the sixth embodiment of the same, and Figure 4 is an enlarged view of the bearing part in the structure of Figure 3.
FIG. 6 is a diagram of the fifth embodiment, FIG. 7 is a diagram of the sixth embodiment, and FIG. 8 is a diagram of the seventh embodiment.

1・・・・・・・・・・・・・・・・・・・・・・・・・・・
・Central axis 2・・・・・・・・・・・・・・・・・・
・・・・・・Upper drum 3・・・−・・・・−・・・・
・・・・・・・・・・・・Lower drum 4・・・・・・・・・
・・・・・・・・・・・・・・・・・・Rotating structure 5
a~5d・・・・・・・・・・・・Bearing 8...
・・・・・・－・・・・・・・・・・・・・・・ Head 14.15・・・・・・・・・・・・・・・Rotating transformer 21.21 ', 21'...Stator coil 22. 22'... Hitting... Rotating yoke 229...・・・・・・
・−・Stator yoke +8. +8α・・・・・・−・・
......First rotor magnet 18b of the first motor......Second rotor magnet of the first motor +8' , +8',......First rotor magnet 18'b of second motor......
2nd rotor magnet N, I+' of 2nd motor...Pulley No.
・・・・・・・・・・・・・・・Tap・List・Magnetic fixed disk 78・・・・・・・・・・・・・・・・・・・・・・
Head fixed disk 150, 150'... Opening/transmission belt agent Patent attorney Masaru Ogawa Ooya 1 Figure also 2 figures (ml Kushi 31 yen 1 Figure 4 (b) Liu 5 Figure 6 Mo7 Figure 8th Ward

Claims (1)

[Scope of Claims] 1. A rotary head device that directly connects and drives a rotary structure mounted with a recording/reproducing head such as a magnetic head, and rotates and scans the surface of a signal recording medium such as a magnetic tape running on the side surface of a guide drum. , further comprising another motor that rotates coaxially with the rotary structure driving motor and rotates independently of the rotary structure driving motor,
A paired rotor structure consisting of at least one of the plurality of motors as its electromagnetic part, a rotor magnet and a rotating yoke with a stator coil sandwiched between them, or a first rotor magnet and a second rotor magnet. A rotary head device characterized in that it has a configuration. 2. A rotary head device according to claim 1, characterized in that the central shaft supporting the rotary structure is directly or indirectly fixed to the bottom of a fixed guide drum.