JPH031301A - Rotary head device - Google Patents

Abstract

PURPOSE:To eliminate the problems arising from contact by forming a projecting part which regulates the signal wire led out of a stator to the outside of the device so as to prevent the contact thereof with a rotary cylinder and a projecting part for holding the stator on the stator. CONSTITUTION:A stator plate 18 is formed with a contact regulating part 18a which regulates a flexible cable 19 so as to prevent the contact thereof with an upper cylinder 5 and a holding part 18b for holding the stator at the time of assembling or disassembling of the stator in a stage for assembling the head device. The contact regulating part 18a and the holding part 18b are integrally formed to a stator plate 18 and are formed as the projecting pieces continuously bent to the edge of a hole 18c. The contact regulating part 18a is bent horizontally from the edge of the hole 18c to the outer side and the front end part thereof is so formed as to face the top of the upper edge of the upper cylinder 5. The contact of the flexible cable 19 with the upper cylinder 5 is regulated in this way and the easy assembly and disassembly of the stator are executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotary head device, and more specifically, the present invention relates to a rotary head device, and more specifically, it has a fixed cylinder and a rotary cylinder that supports a magnetic head and is coaxially supported with the fixed cylinder. The present invention relates to a rotary head device that slides a magnetic tape of a magnetic recording medium and rotates a rotary cylinder to magnetically record or reproduce information.

[Prior Art] This type of rotating head device is used in a VTR (Video Cheap Recorder). For example, in the rotating head device of general VTRs including home VTRs,
As described in No. 8-190808, etc., a motor that rotationally drives the rotary cylinder is placed under a cylinder section consisting of an upper cylinder (rotating cylinder) that supports a magnetic head and a lower cylinder (fixed cylinder). Therefore, the height of the entire rotary head device inevitably became high.

On the other hand, recently, as described in Japanese Patent Application Laid-open No. 63-164014, etc., the center axes of the upper and lower cylinders are fixed axes, the upper cylinder is supported using a hydrodynamic bearing, and a cylindrical type A structure is adopted in which a rotary transformer is used and the motor is constructed on the outer periphery of the rotary transformer, and the motor is built into the upper and lower cylinders to reduce the thickness of the entire device.

However, VTRs with built-in cameras have four heads instead of the conventional two heads, and the cylinder diameter is smaller than the usual two.
/3, and a configuration in which the rotational speed of the cylinder is conversely increased by 3/2 is widely used. A camera like this > V
In the TR, the above-mentioned configuration using a hydrodynamic bearing and a cylindrical rotary transformer has problems such as the fact that the shaft torque changes greatly depending on the temperature, becomes significantly larger as the temperature drops, and that there is a limit to how thin it can be made. Not suitable.

Therefore, in recent rotary head devices for camera-integrated VTRs, a configuration is being used in which the central axis is similarly fixed, a rotary transformer is disposed on the lower cylinder side, and a motor is disposed on the upper cylinder side.

[Problem to be solved by the invention] In recent camera-integrated VTRs, the cylinder of the rotary head device fits inside the cassette when a magnetic tape cassette is attached, so the motor is placed on the upper cylinder side as described above. In this configuration, the condition is that the motor does not protrude significantly above the upper cylinder. For this reason, it is important to reduce the thickness and position of the motor. In order to reduce the thickness of the motor, the stator of the motor is fixed to the upper cylinder side end of the central axis (fixed shaft) of the cylinder, and the height of the upper surface of the stator is made to be approximately the same as the upper surface of the upper cylinder. However, such a structure causes the following two problems.

(a) In the final process of assembling a rotary head device, the stator of the motor is assembled into the device, and sometimes the only place to hold the disk-shaped stator is its outer periphery. As a result, the stator is assembled with an impact due to the magnetic attraction between the motor's stator and the drive magnet, and the jig that had previously held the outer circumference of the stator comes into contact with the upper cylinder, causing damage to the bearing. Impact loads are often applied. Additionally, when the stator is assembled, the outer circumference of the stator that can hold the stator with a jig is hidden inside the upper cylinder, and the stator is held by the strong attraction of the magnet, making it difficult to remove the stator. 6 (b) Assuming that the heights of the top surface of the motor stator and the top surface of the upper cylinder are approximately the same, the wires or cables of signal lines led from the stator to the board of the motor drive control circuit outside the device will be connected to the upper cylinder, That is, it tends to come into contact with the rotating cylinder, and if it comes into contact with it, problems such as uneven rotation of the rotating cylinder will occur.

Therefore, it is an object of the present invention to solve the above-mentioned problems in this type of rotary head device.

[Means for Solving the Problems] In order to solve the above problems, the present invention includes a fixed cylinder fixed to a fixed shaft, and a rotary cylinder supporting a magnetic head and rotatably bearing on the fixed shaft. A rotary head device in which a motor for rotationally driving the rotary cylinder is provided in the rotary cylinder, and a stator of the motor is fixed to an end of the fixed shaft on the rotary cylinder side, the stator being led out from the device. A structure is adopted in which the stator is provided with a protrusion that prevents the signal line from coming into contact with the rotating cylinder, and a protrusion that holds the stator.

[Function] According to such a structure, the two protrusions of the stator can restrict the signal line led out from the stator to the outside of the device from coming into contact with the rotating cylinder, and also prevent the stator from being incorporated into the one-rotation head device. The stator can be held securely during installation and removal.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

First Embodiment FIGS. 1 to 3 illustrate the structure of a rotary head device according to a first embodiment of the present invention. It is assumed that this rotary head device is used in a camera-integrated VTR.

In FIGS. 1 and 2, numeral 4 is the lower cylinder, and numeral 5 is the lower cylinder.
is the upper cylinder, and during recording and playback, both cylinders 4
．． A magnetic tape of a magnetic recording medium (not shown) is wound around the lower cylinder 5 so that it slides.The lower cylinder 4 is a fixed cylinder, and the upper cylinder 5 is a cylinder at the lower end of the cylinder 4.
It is a rotating cylinder that rotates while supporting a magnetic head 8 fixed at a location with a screw 31.

As shown in FIG. 2, a lead 4a is formed on the outer peripheral surface of the lower cylinder 4 for obliquely guiding the sliding path of a magnetic tape (not shown). Further, a groove 5a is formed on the outer peripheral surface of the upper cylinder 5 to stabilize the air film formed between the magnetic tape and the upper cylinder 5 during recording and reproduction.

Next, as shown in FIG. 1, on the inner bottom surface of the lower cylinder 4 is a transformer stator section 7 that constitutes a rotary transformer for outputting recording and reproducing signals to the rotating magnetic head without contact. Fixed. A hole 4b is formed in the center of the lower cylinder 4, and a fixed shaft 1 is fitted into this hole 4b and fixed. The upper cylinder 5 is rotatably supported by this fixed shaft l.

Bearings (ball bearings) 2a and 2b are rotatably attached to the fixed shaft l. Balls 2C of the bearings 2a and 2b are rotatably fitted into grooves 1a and lb formed on the outer periphery of the fixed shaft l, respectively. That is, the bearings 2a and 2b are bearings with shafts centered on the fixed shaft l.

A transformer stand 3 is fitted and fixed to the outside of the bearings 2a, 2b. A transformer rotor section 6 constituting a low retransformer is fixed to the lower surface of the transformer stand 3, and faces a transformer stator section 7 with an extremely small gap therebetween. Terminals 9 are provided protrudingly on the transformer rotor section 6, and these terminals 9 are pressed into contact with the wiring board 8a of the magnetic head 8 fixed to the lower surface of the upper cylinder 5, thereby connecting the transformer rotor section 6.
is connected to the magnetic head 8.

On the other hand, an upper cylinder 5 is fitted and fixed to the upper part of the transformer stand 3. That is, a cylindrical boss portion 5b is formed in the center of the upper cylinder 5, and this boss portion 5b is connected to the transformer stand 3.
is fitted onto the top of the holder and fixed.

Next, a motor for rotationally driving the upper cylinder 5 is provided inside the upper cylinder 5. This motor is composed of the following members indicated by numerals IO to 21 in FIG.

First, reference numeral 11 is a drive magnet, and reference numeral 13 is a rotor yoke, which are fixed to the upper and lower surfaces of the root 12, respectively. For installation, the magnet 11 and rotor yoke 13 are fixed within the upper cylinder 5 by tightening the plate 12 onto the boss portion 5b of the upper cylinder 5 with screws 32.

Reference numeral 10 denotes a motor pedestal, which is fixed to the end of the fixed shaft 1 on the upper cylinder 5 side by screwing, press-fitting, or the like. A stator of the motor is fixed onto this motor pedestal 10.

This stator is constructed by laminating and bonding a first stator plate 17 made of glass epoxy or the like as a double-sided through-hole substrate, and a second stator plate 18 which is a magnetic plate made of iron plate, silicon steel plate, etc. stator i
17 is fixed to the end of the fixed shaft 1 by tightening the screw 33 onto the motor pedestal lO.

A coil 14 is fixed to the lower surface of the stator plate 17 and faces the drive magnet 11. Further, a PG coil 16 constituting a pulse generator for detecting the rotational phase of the motor is fixed at a predetermined position on the lower surface of the stator plate 17. On the other hand, a PG magnet 15 constituting the pulse generator is fixed to the upper surface of the plate 12. As the mounting plate 12 is rotated by driving the motor, the PG coil I6 generates a pulse every time the PG magnet 15 passes in front of the PG coil 16. That is, one pulse is generated from the PG coil 16 for one rotation of the motor, and the rotational phase of the motor is thereby detected. Further, although not shown, an FG pattern for detecting the rotational speed of the motor is provided on the lower surface of the stator i17.

On the other hand, near the center of the -E surface of the stator plate 17, the motor is connected to V.
A flexible cable 19, which is a signal line cable for connecting to an unillustrated motor drive control circuit of the TR, is designated by reference numeral 1.
The parts 9a are connected by soldering, welding, or the like. each of coils 14 and PG coil 1
6 is connected to this cable 19 via a through ball (not shown) of the stator plate 17 and a wiring pattern.

The stator plate 18 of the second option is formed as a disk having a hole 18c in the center, as shown in FIG. The stator plate 18 includes a contact regulating portion 18a that regulates the flexible cable 19 from coming into contact with the upper cylinder 5, and a holder for holding the stator when the stator is assembled or removed during the assembly process of the head device. A portion 18b is formed.

The contact regulating portion 18a and the holding portion tab are integrally formed on the stator plate 18, and are formed as a bent protrusion continuous with the edge of the hole 18c. The contact regulating portion 18a is bent horizontally outward from the edge of the hole 18c, and its tip is formed so as to face the upper edge of the upper cylinder 5, as shown in FIG. The flexible cable 19 then passes over the contact regulating portion 18a and is led out to the outside as shown in FIG.

Further, the holding portion tab is bent upward perpendicularly to the main body portion of the stator plate 18 from the edge of the hole 18c. When installing or removing the stator, this holding portion 18b
The stator can be held securely through the

FIG. 3 shows the positional relationship of the contact regulating portion 18a and the holding portion 18b with respect to the magnetic tape cassette when the magnetic tape cassette is attached to the VTR. In the same figure,
Reference numeral 22 is a cassette, and 22a is a cassette lid attached to the cassette 22.

As shown in FIG. 3, when the cassette 22 is installed, about half of the upper cylinder 5 is inserted into the cassette 22. Therefore, the contact regulating portion 18a and the holding portion 18b are formed on the side of the stator i18 that does not enter the cassette 22 so as not to contact the cassette 422a.

Furthermore, components of the motor indicated by reference numerals 20 and 21 in FIG. 1 are a ground terminal and a ground plate for grounding static electricity generated between the upper cylinder 5 and the magnetic tape during recording and reproduction, respectively.

The ground plate 21 is fixed to the upper surface of the transformer base 3 and is electrically connected to the upper cylinder 5 via the transformer base 3 made of conductive metal. A base end portion of the ground terminal 20 is fixed to the lower surface of the motor pedestal 10.

The tip portion 20a slidably contacts the upper surface of the ground plate 21. In this way, the motor is constructed from six or more members to which the upper cylinder 5 is grounded via the transformer stand 3, the ground plate 21, and the ground terminal 20. During recording and reproduction of the VTR, the coil 14 is energized via the flexible cable 19 from an external motor control circuit (not shown), the coil 14 is excited, and magnetic force acts between the coil 14 and the drive magnet 11. ．． During installation, the plate 12 and rotor yoke 13 are rotated, and together with this, the upper cylinder 5 is rotated, and the magnetic head 8 is rotated.

Then, the magnetic head 8 slides on a magnetic tape (not shown) that is wound around the cylinder 4.5 and slides, thereby recording data.

According to the rotary head device of this embodiment as shown in E below, the stator! Since the flexible cable 19 is prevented from coming into contact with the upper cylinder 5 via the contact regulating portion 18a of the Fi 18, problems such as uneven rotation of the upper cylinder 5 due to such contact can be reliably prevented.

Furthermore, when the stator consisting of the stator ff117.18 is installed in or removed from the rotating device, the stator can be firmly held via the holding portion 18b of the stator plate 18. Therefore, it is easy to assemble or remove the stator.Furthermore, the contact regulating portion 18a and the holding portion 18b are integrated with the stay +SXS, and can be formed by pressing at an extremely low cost.

The reason why the contact regulating part 18a and the holding part 18b are bent from the edge of the hole 18c inside the stator plate 18 in the structure of this embodiment is because the magnet 11, rotor yoke 13, and stator plate 18 are bent when the motor is driven. This is to prevent disturbances in the flow of magnetic flux flowing through the magnetic circuit consisting of the coil 14 and the coil 14. By doing so, it is possible to prevent problems such as motor torque fluctuations, so-called cogging, caused by the flow of magnetic flux.

Second Embodiment Next, FIGS. 4 and 5 illustrate the structure of a rotary head device according to a second embodiment of the present invention. The device of this embodiment has the structure of the device of the first embodiment described above. The parts in FIGS. 4 and 5 that are common or corresponding to those in FIGS. 1 to 3 of the first embodiment are given the same reference numerals. Description of parts in this embodiment that are common to the apparatus of the first embodiment will be omitted.

The apparatus of this embodiment shown in FIGS. 4 and 5 is different from the first embodiment in that the first stator plate 17 is a magnetic plate such as an iron plate or a silicon steel plate.

As shown in FIG. 4, a flexible printed circuit board 23 on which wiring patterns for the coil 14, PG coil 16, etc. are formed is fixed to its lower surface. The terminal portion 23a at the tip of the flexible printed circuit board 23 is folded back along the outer periphery of the stator plate 17, 18, as shown in FIG.
It is fixed to the upper surface of the second stator plate 18.

The second stator plate 18 is a magnetic plate such as an iron plate or a silicon steel plate, and a wiring pattern (not shown) for connecting the coil 14, PG coil 16, etc. is formed on its upper surface. Then, the terminal portions 23a of the flexible printed circuit boards 23 of the 17 stator plates are fixed to the wiring patterns (not shown) on the stator plate 18 by soldering.
Connected. Further, a flexible cable 19 for leading out to the outside is connected to the wiring pattern on the stator plate 18 by soldering or the like.

Furthermore, the stator plate 18 is provided with a contact regulating portion 18a for regulating the flexible cable 9 from coming into contact with the upper cylinder 5.
A holding portion 18b is integrally formed with the stator plates 18 and 19 to hold the stator when the stator is assembled into or removed from the device. Note that the holding part 18
b is formed as a protruding piece bent from the edge of the hole 18c inside the stator plate 18 as in the first embodiment, whereas the contact regulating part 18a is formed by handling the stator differently from the first embodiment. It is formed as a protruding piece bent into an L shape from the outer edge of 18.

With the structure of this embodiment as well, the same effects as in the first embodiment can be obtained through the contact regulating portion 18a and the holding portion 18b of the stator plate 18.

Note that in the above structure, a contact regulating portion and a holding portion may be formed on the lower stator plate 17. In this case, the contact regulating portion and the holding portion are formed by cutting and bending the stator plate 17 from a region inside the hole 18c of the stator plate 18.

[Effects of the Invention] As is clear from the above description, the present invention includes a fixed cylinder fixed to a fixed shaft, and a rotating cylinder supporting a magnetic head and rotatably bearing on the fixed shaft, In a rotary head device in which a motor for rotationally driving the rotary cylinder is provided in the rotary cylinder, and a stator of the motor is fixed to an end portion of the fixed shaft on the rotary cylinder side, a signal is derived from the stator to the outside of the device. A structure is adopted in which the stator is formed with a protrusion that restricts the wires from coming into contact with the rotating cylinder, and a protrusion that holds the stator, so that the signal wires led out from the stator to the outside of the device are connected to the rotating cylinder. It is an excellent product that can prevent problems caused by such contact, and can also securely hold the stator when assembling and removing the stator from a one-turn head device, making it easy to assemble and remove the stator without any problems. Effects can be obtained.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing the structure of a rotary head device according to a first embodiment of the present invention, FIG. 2 is a perspective view showing the external appearance of the head device, and FIG. 3 is a magnetic tape of a VTR in which the device is incorporated. An explanatory diagram showing the positional relationship between the contact regulating part of the stator plate and the holding part with respect to the cassette when the cassette is installed. FIG. 4 is a longitudinal sectional view showing the structure of the rotary head device according to the second embodiment, and FIG. 5 is the same device. FIG. ■...Fixed shaft 2a, 2b...Bearing 3...
・Transformer stand 4...Lower cylinder 5...Upper cylinder 6...Transrotor section 7...Transformer stator section 8...Magnetic head lO...-Motor pedestal 11...Drive magnet 12...・Installation is by the root
13... Rotor yoke 14... Coil 1
5...PG magnet 16...PG coil 17
...-first stator plate 18... second stator plate
18a...Contact regulation part 18b...Holding part 19...-Flexible cable 23...-Flexible printed circuit board 1aa ft#, al length P color] J part, foundation wo drum, 7 thighs 1 shoL =dhf4man 3rd
figure

Claims (1)

[Claims] 1) It has a fixed cylinder fixed to a fixed shaft, and a rotating cylinder that supports a magnetic head and is rotatably supported by the fixed shaft, and a motor that rotationally drives the rotating cylinder is provided in the rotating cylinder, In a rotary head device in which a stator of the motor is fixed to an end portion of the fixed shaft on the rotating cylinder side, a protruding portion restricts a signal line led out from the stator to the outside of the device from contacting the rotating cylinder; A rotary head device characterized in that the stator is provided with a protrusion for holding the stator.