JP2002208199A - Head cylinder device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head cylinder device which is inexpensive, having high durability and capable of carrying out precise finishing. SOLUTION: The head cylinder device is provided with a fixed cylinder and a rotary cylinder having a magnetic head arranged concentric-circularly, and designed to record, reproduce or erase information on a magnetic tape by traveling the magnetic tape along the peripheral surfaces of both the cylinders. Both or one of the cylinders is provided with a synthetic resin cylinder main body 10, and a metal outer ring 11 burned to fit the outer peripheral surface of the cylinder main body 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head cylinder device for recording, reproducing or erasing information on a magnetic tape such as a video tape recorder.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a conventional head cylinder device. It has a fixed cylinder 1 and a rotary cylinder 6 with a magnetic head 5 rotatably fitted via a bearing 4 to a support shaft 3 inserted into a central through hole 2 of the fixed cylinder 1. In addition, 7 is a rotary transformer and 8 is a motor.

In the above configuration, the magnetic tape t runs along the outer peripheral surfaces of the cylinders 1 and 6 to record, reproduce, or erase information on the magnetic tape t.

[0004] Each of the cylinders 1 and 6 is manufactured by subjecting an aluminum material formed by die-casting aluminum to a cutting process. In this case, the die-casting mold is severely worn. There is a drawback that it is necessary to replace it in a short period of time and the cost of the mold is expensive.

Therefore, as described in Japanese Utility Model Laid-Open No. 3-89513, it is conceivable to form the cylinders 1 and 6 by insert-molding a conductive synthetic resin on a metal core material such as aluminum. Have been.

[0006]

In the above structure, the synthetic resin to be insert-molded has a much larger shrinkage ratio and deformation amount at the time of solidification than aluminum. In addition, a gap or a crack may be generated between the aluminum core material and the insert-molded synthetic resin, and it may be difficult to integrate both of them, resulting in poor durability.

An object of the present invention is to provide a head cylinder device which is inexpensive, durable and can be precisely finished in view of the above-mentioned conventional disadvantages.

[0008]

According to a first aspect of the present invention, there is provided a stationary cylinder and a rotary cylinder with a magnetic head which are concentrically arranged. By running the magnetic tape, in a head cylinder device that performs recording, reproduction or erasure of information on the magnetic tape, both or one of the two cylinders, a synthetic resin cylinder body, The cylinder body includes a metal outer ring disposed on an outer peripheral surface of the cylinder body, the cylinder body having a disk portion, and a cylindrical portion integrally formed on an outer periphery of the disk portion, wherein the cylindrical portion and the disk Reinforcing ribs are integrally formed at corners between the cylindrical portion and a large number of convex portions having minute heights are formed on the entire outer peripheral surface of the cylindrical portion, and the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring are formed. On one side With Ritome ridges are formed, are other fittable groove in detent protrusion towards the formation, and characterized in that shrink-fitted to the outer ring on the cylindrical portion.

According to the above construction, both or one of the fixed cylinder and the rotary cylinder is formed by shrink-fitting a metal outer ring on a synthetic resin cylinder main body. Is unnecessary, the manufacturing cost is low, and since the cylinder body is formed of synthetic resin, since it is molded in a predetermined shape in advance,
It is not necessary to take into account shrinkage and deformation during solidification, and even if the outer ring is heated to, for example, 200 ° C. for shrink fitting, the diameter of the cylinder is only slightly increased by about 0.2 mm. Can be set precisely,
The shrink fit allows the cylinder body and the outer ring to be firmly integrated, and has excellent durability.

The cylinder body is composed of a disk portion and a cylindrical portion, and the inner peripheral surface of the outer ring is pressed against the outer peripheral surface of the cylindrical portion over a wide range by shrink fitting. Can be integrated.

Since the compressive force generated when the outer ring is reduced in diameter by annealing is received by the reinforcing rib integrally formed at the corner between the disk portion and the cylindrical portion, the deformation of the cylindrical portion is prevented. The cylinder dimensions can be set more precisely.

When the inner peripheral surface of the outer ring is pressed into contact with the tips of a large number of convex portions formed on the entire outer peripheral surface of the cylindrical portion by shrink fitting, a gap between the outer ring and the cylindrical portion is formed by the concave portions between the multiple convex portions. Is formed, the gap can absorb a shift in the amount of expansion and contraction due to a temperature change between the cylinder body made of synthetic resin and the outer ring made of metal, and thereby the integrated state of the outer ring and the cylindrical portion can be controlled by the temperature. It can always be reliably maintained following changes.

The outer ring is connected to the outer peripheral surface of the cylindrical portion by fitting a groove formed on the other side into a rotation preventing ridge formed on one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring. The surface can be integrated so as not to run idle.

According to a second aspect of the present invention, there is provided a stationary cylinder and a rotary cylinder with a magnetic head which are arranged concentrically.
By running a magnetic tape along the outer peripheral surfaces of the two cylinders, in a head cylinder device for recording, reproducing, or erasing information on the magnetic tape, both or one of the two cylinders is used. ,
It is characterized by comprising a synthetic resin cylinder body and a metal outer ring shrink-fitted on the outer peripheral surface of the cylinder body.

According to the above construction, both or one of the fixed cylinder and the rotary cylinder is formed by shrink-fitting a metal outer ring on a cylinder body made of a synthetic resin. Is unnecessary, the manufacturing cost is low, and since the cylinder body is formed of synthetic resin, it is formed in a predetermined shape in advance,
It is not necessary to take into account shrinkage and deformation during solidification, and even if the outer ring is heated to, for example, 200 ° C. for shrink fitting, the diameter of the cylinder is only slightly increased by about 0.2 mm. Can be set precisely,
The shrink fit allows the cylinder body and the outer ring to be firmly integrated, and has excellent durability.

According to a third aspect of the present invention, in the second aspect of the present invention, the cylinder body includes a disk portion and a cylindrical portion integrally formed on an outer periphery of the disk portion. The outer ring is shrink-fitted on a surface.

According to the above structure, the cylinder body is composed of the disk portion and the cylindrical portion, and the inner peripheral surface of the outer ring is pressed against the outer peripheral surface of the cylindrical portion over a wide range by shrink fitting. Can be reliably integrated into the cylinder body.

According to a fourth aspect of the present invention, in the third aspect of the present invention, a reinforcing rib is integrally formed at a corner between the disk portion and the cylindrical portion.

According to the above configuration, the compressive force generated by the outer ring being reduced in diameter by annealing is received by the reinforcing rib integrally formed at the corner between the disk portion and the cylindrical portion.
By preventing deformation of the cylindrical portion, the cylinder dimensions can be set more precisely.

The invention according to claim 5 is the invention according to claim 3 or 4.
In the invention described in the above, a large number of convex portions having a minute height are formed on the entire outer peripheral surface of the cylindrical portion.

According to the above construction, when the inner peripheral surface of the outer ring is pressed into contact with the tip of a large number of convex portions formed on the entire outer peripheral surface of the cylindrical portion by shrink fitting, the outer ring and the cylindrical portion are formed by the concave portions between the multiple convex portions. Since a gap is formed between the outer ring and the cylindrical portion, it is possible to absorb a shift in the amount of expansion and contraction due to a temperature change between the cylinder body made of synthetic resin and the outer ring made of metal due to the gap. Can always be reliably maintained by following the temperature change.

The invention according to claim 6 is the invention according to any one of claims 3 to 5, wherein one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring is provided with a rotation preventing ridge. It is characterized in that it is formed and a concave groove is formed on the other side so as to be fitted to the rotation preventing ridge.

According to the above construction, the outer ring is formed by fitting the detent groove formed on the other side into the rotation preventing ridge formed on one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring. Can be firmly integrated with the outer peripheral surface of the cylindrical portion so as not to run idle.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the cylinder body is formed of injection-molded polyphenylene sulfide, and the outer ring is formed of pressed aluminum. It is characterized by having.

According to the above construction, a polyphenylene sulfide is injection-molded to form a cylinder main body having excellent mechanical strength, and aluminum is pressed to form an inexpensive and high-precision outer ring. Since an expensive mold is not required to integrate the cylinder and the cylinder body, the production cost is low, and since the cylinder body is preformed into a predetermined shape, shrinkage and deformation during solidification are considered. In addition, since the outer ring is only slightly expanded by about 0.2 mm even if it is heated to, for example, 200 ° C. for shrink fitting, the cylinder dimensions can be set precisely. Further, the cylinder body and the outer ring can be firmly integrated by shrink fitting, and the durability is excellent.

According to an eighth aspect of the present invention, in the first aspect of the present invention, the cylinder body is formed of injection-molded polyphenylene sulfide, and the outer ring is formed of extruded aluminum. It is characterized by having.

According to the above construction, a polyphenylene sulfide can be injection-molded to form a cylinder body having excellent mechanical strength, and aluminum can be extruded to form an inexpensive and high-precision outer ring. Almost the same effects as those of the invention described in Item 7 can be obtained.

According to a ninth aspect of the present invention, in the invention according to any one of the first to sixth aspects, the cylinder body is formed of thermoset unsaturated polyester, and the outer ring is formed of extruded aluminum. It is characterized by being formed.

According to the above configuration, the cylinder body having excellent mechanical strength can be formed by thermosetting the unsaturated polyester, and the inexpensive and high precision outer ring can be formed by extruding aluminum. It is possible to obtain substantially the same effects as the seventh aspect of the present invention.

The invention according to claim 10 is the invention according to claims 1 to 6
In the invention according to any one of the above, the cylinder body is formed of a thermosetting unsaturated polyester,
The outer ring is formed of pressed aluminum.

According to the above construction, the cylinder body having excellent mechanical strength can be formed by thermosetting the unsaturated polyester, and the inexpensive and high-precision outer ring can be formed by pressing aluminum. It is possible to obtain substantially the same effects as the seventh aspect of the present invention.

[0032]

1 to 4 show a fixed cylinder 1 which is a main part of a head cylinder device according to an embodiment of the present invention. The fixed cylinder 1 is made of injection-molded polyphenylene sulfide or thermosetting molding. A cylinder body 10 made of a heat-resistant synthetic resin such as unsaturated polyester which is sufficiently resistant to a shrink-fit temperature (for example, 200 ° C.) and does not deform;
The cylinder body 10 comprises an outer ring 11 made of a metal such as aluminum that has been pressed or extruded and is disposed on the outer peripheral surface of the cylinder body 10. A cylindrical portion 10b integrally formed on the outer periphery of the disk portion 10a, and the width h of the cylindrical portion 10b and the outer ring 11 is set to be substantially the same;
A plurality of substantially right-angled triangular reinforcing ribs 10c are integrally formed at predetermined intervals in the circumferential direction at a corner portion between the outer peripheral surface of the cylindrical portion 10b and the convex portion 12 having a minute height. (See FIG. 4), a plurality of ridges 13 are formed on the inner peripheral surface of the outer ring 11 at predetermined intervals along the circumferential direction, and each ridge 13 is formed on the outer peripheral surface of the cylindrical portion 10b. A concave groove 14 that can be fitted is formed. Reference numeral 15 denotes a cable insertion hole penetrating through the disk portion 10a.

FIG. 5 shows a shrink fit jig 17 in which a center shaft 18 having an outer diameter slightly smaller than the inner diameter of the central through hole 2 of the cylinder body 10 is fixed at the center. A jig body 17a, and a concave portion 19 having an inner diameter slightly larger than the outer diameter of the outer ring 11 heated and expanded for shrink fitting on the upper surface of the jig body 17a around the central axis 18. The inner surface shape of the concave portion 19 is formed according to the outer surface shape of the cylinder body 10.

The procedure of shrink fitting will be described with reference to FIG.
As shown in (1), by fitting the central through hole 2 of the cylinder body 10 formed into a predetermined shape to the center shaft 18, the cylinder body 10 is fitted into the concave portion 19. Next, as shown in FIG. 2B, the outer ring 11 is heated to about 200 ° C. to increase its inner diameter D by, for example, about 0.2 mm so that the outer ring 11 is slightly smaller than the outer diameter d of the cylinder body 10. The outer ring 11 is inserted into the recess 19 in a state where the outer ring 11 is enlarged. Thereby, the outer ring 11 and the cylindrical portion 10b of the cylinder body 10 have a small interval α (for example, about 0.1 mm).
To face each other. Subsequently, by performing annealing, the outer ring 11 is reduced in diameter and pressed against the cylindrical portion 10b of the cylinder body 10 as shown in FIG.
The cylinder body 10 and the outer ring 11 are integrated. Thereafter, the cylinder body 10 may be taken out of the recess 19.

According to the above configuration, the fixed cylinder 1 is formed by shrink-fitting the metal outer ring 11 into the synthetic resin cylinder body 10, and an expensive mold is not required at the time of the formation. Therefore, the manufacturing cost is low, and the cylinder body 10 is formed of a synthetic resin. However, since the cylinder body 10 is formed in a predetermined shape in advance, it is not necessary to take into account shrinkage and deformation during solidification, and furthermore, the outer ring For example, even if the cylinder 11 is heated to 200 ° C. for shrink fitting, the diameter of the cylinder is only slightly increased by about 0.2 mm, so that the cylinder dimensions can be set precisely. 10 and the outer ring 11 can be firmly integrated, and the durability is excellent.

The cylinder body 10 is composed of a disk portion 10a and a cylindrical portion 10b, and the inner peripheral surface of the outer ring 11 is pressed against the outer peripheral surface of the cylindrical portion 10b over a wide range by shrink fitting. Can be surely integrated with the cylinder body 10.

The compressive force generated when the outer ring 11 is reduced in diameter by annealing is received by the reinforcing ribs 10c, so that the deformation of the cylindrical portion 10b is prevented and the cylinder dimensions can be set more precisely.

As shown in FIG. 4A, the heated outer race 1
From the state in which the outer ring 11 is opposed to the cylindrical portion 10b of the cylinder body 10 (see FIG. 5B), the outer ring 11 is reduced in diameter by annealing to form a large number of inner circumferential surfaces on the entire outer circumferential surface of the cylindrical portion 10b. When pressed against the tip of the convex portion 12, a gap β is formed between the outer ring 11 and the cylindrical portion 10 b by the concave portions between the large number of convex portions 12. And outer ring 11 made of metal
Can be absorbed by the change in the amount of expansion and contraction due to the temperature change, whereby the integrated state of the outer ring 11 and the cylindrical portion 10b can always be reliably maintained by following the temperature change.

A detent ridge 1 formed on the outer race 11
By fitting the groove 3 into the groove 14 formed in the cylindrical portion 10b, the outer ring 11 can be integrated with the outer peripheral surface of the cylindrical portion 10b so as not to run idle.

In the above-described embodiment, the ridge 13 is connected to the outer ring 1.
1 and the concave groove 14 is formed in the cylindrical portion 10b. Conversely, the ridge 13 may be formed in the cylindrical portion 10b and the concave groove 14 may be formed in the outer ring 11. Further, it is sufficient that at least one of the ridge 13 and the concave groove 14 is formed.

[0041]

First Embodiment A cylinder body 10 is formed of injection-molded polyphenylene sulfide (PPS), and an outer ring 11 is formed of pressed aluminum.

[Second Embodiment] The cylinder body 10 is formed of injection-molded polyphenylene sulfide (PPS), and the outer ring 11 is formed of extruded aluminum.

[Third Embodiment] The cylinder body 10 is made of thermoset unsaturated polyester, and the outer race 11 is made of extruded aluminum.

Fourth Embodiment The cylinder body 10 is made of thermoset unsaturated polyester, and the outer race 11 is made of pressed aluminum.

As the polyphenylene sulfide and the unsaturated polyester, those having a composition having a coefficient of linear expansion close to that of aluminum and having a small shrinkage in a different direction are selected.

According to the first to fourth embodiments, the cylinder main body 10 having excellent mechanical strength is formed by injection molding of polyphenylene sulfide or thermosetting of unsaturated polyester, and press working of aluminum. Inexpensive and high-precision outer ring 11 can be formed by extrusion or extrusion, and since the outer ring 11 and the cylinder main body 10 are integrated with each other, an expensive mold is not required. In addition, since the cylinder body 10 is formed in a predetermined shape in advance, it is not necessary to take into account shrinkage and deformation during solidification.
Even when heated to 00 ° C, the diameter of the cylinder is only slightly increased by about 0.2 mm, so the cylinder dimensions can be set precisely, and the cylinder body 10 and outer ring 11 are firmly integrated by shrink fitting. It has excellent durability.

In the above embodiment, the case where the fixed cylinder 1 is formed has been described as an example.
Can be similarly formed.

[0048]

According to the first aspect of the present invention, both or one of the fixed cylinder and the rotary cylinder is formed by shrink-fitting a metal outer ring on a synthetic resin cylinder body. In this case, an expensive mold is not required, so that the manufacturing cost is low.Also, although the cylinder body is formed of synthetic resin, since the cylinder body is formed in a predetermined shape in advance, consideration is given to shrinkage and deformation during solidification. In addition, since the outer ring is heated to 200 ° C. for shrink-fitting and is only slightly expanded by about 0.2 mm, the cylinder dimensions can be set precisely. ,
The shrink fit allows the cylinder body and the outer ring to be firmly integrated, and has excellent durability.

The cylinder body is composed of a disk portion and a cylindrical portion, and the inner peripheral surface of the outer ring is pressed against the outer peripheral surface of the cylindrical portion over a wide range by shrink fitting. Can be integrated.

The compressive force generated when the outer ring is reduced in diameter by annealing is received by the reinforcing ribs integrally formed at the corners between the disk portion and the cylindrical portion, so that the deformation of the cylindrical portion is prevented. The cylinder dimensions can be set more precisely.

When the inner peripheral surface of the outer ring is pressed against the tip of a large number of convex portions formed on the entire outer peripheral surface of the cylindrical portion by shrink fitting, a gap between the outer ring and the cylindrical portion is formed by the concave portion between the multiple convex portions. Is formed, the gap can absorb a shift in the amount of expansion and contraction due to a temperature change between the cylinder body made of synthetic resin and the outer ring made of metal, and thereby the integrated state of the outer ring and the cylindrical portion can be controlled by the temperature. It can always be reliably maintained following changes.

The outer ring is formed on the outer peripheral surface of the cylindrical portion by fitting a detent groove formed on one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring with a detent ridge formed on one of them. The surface can be integrated so as not to run idle.

According to the second aspect of the present invention, both or one of the fixed cylinder and the rotary cylinder is formed by shrink-fitting a metal outer ring on a synthetic resin cylinder body. Since an expensive mold is not required, the manufacturing cost is low, and the cylinder body is formed of a synthetic resin. However, since the cylinder body is formed in a predetermined shape in advance, shrinkage and deformation during solidification are taken into consideration. It is not necessary, and for example, 200 ° C for shrink fitting of the outer ring
Even when heated, the diameter of the cylinder is expanded only slightly by about 0.2 mm, so the cylinder dimensions can be set precisely,
Further, the cylinder body and the outer ring can be firmly integrated by shrink fitting, and the durability is excellent.

According to the third aspect of the present invention, the cylinder body is composed of a disk portion and a cylindrical portion, and the inner peripheral surface of the outer ring is pressed against the outer peripheral surface of the cylindrical portion over a wide range by shrink fitting. Therefore, the outer ring can be surely integrated with the cylinder body.

According to the fourth aspect of the present invention, the compressive force generated when the outer ring is reduced in diameter by annealing is received by the reinforcing rib integrally formed at the corner between the disk portion and the cylindrical portion. By preventing deformation of the cylindrical portion, the cylinder dimensions can be set more precisely.

According to the fifth aspect of the present invention, when the inner peripheral surface of the outer ring is pressed against the tips of a large number of convex portions formed on the entire outer peripheral surface of the cylindrical portion by shrink fitting, the concave portions between the multiple convex portions are formed. As a result, a gap is formed between the outer ring and the cylindrical portion, so that the gap can absorb a shift in the amount of expansion and contraction due to a temperature change between the cylinder body made of synthetic resin and the outer ring made of metal. The integrated state of the cylinder and the cylindrical portion can always be reliably maintained by following the temperature change.

According to the sixth aspect of the present invention, of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring, the detent groove formed on the other is fitted into the detent ridge formed on one of them. Thus, the outer ring can be firmly integrated with the outer peripheral surface of the cylindrical portion so as not to run idle.

According to the seventh aspect of the present invention, it is possible to form a cylinder body having excellent mechanical strength by injection molding polyphenylene sulfide, and to form an inexpensive and highly accurate outer ring by pressing aluminum. No expensive mold is required to integrate the outer ring with the cylinder body, which reduces production costs. In addition, since the cylinder body is formed in a predetermined shape in advance, shrinkage during solidification occurs. It is not necessary to take into account the deformation and deformation, and even if the outer ring is heated to, for example, 200 ° C. for shrink fitting, it is 0.2 mm
Because the diameter is increased only slightly, the cylinder dimensions can be set precisely, and the cylinder body and outer ring can be firmly integrated by shrink fitting, and the durability is excellent. .

According to the eighth aspect of the present invention, it is possible to form a cylinder body having excellent mechanical strength by injection molding polyphenylene sulfide, and to form an inexpensive and high precision outer ring by extruding aluminum. Thus, substantially the same effects as those of the invention described in claim 7 can be obtained.

According to the ninth aspect of the present invention, the unsaturated polyester is thermoset-molded to form a cylinder body having excellent mechanical strength, and aluminum is extruded to form an inexpensive and high-precision outer ring. Claim 7
Almost the same effects as those of the described invention can be obtained.

According to the tenth aspect of the present invention, the cylinder body having excellent mechanical strength is formed by thermosetting molding the unsaturated polyester, and the inexpensive and high precision outer ring is formed by pressing aluminum. Claim 7
Almost the same effects as those of the described invention can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a fixed cylinder which is a main part of a head cylinder device according to an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is an exploded perspective view of the same.

FIG. 4A is an enlarged partial cross-sectional view of the state before the shrink fit, and FIG. 4B is an enlarged partial cross-sectional view of the shrink fit state.

FIGS. 5A to 5C are schematic longitudinal sectional views showing a shrink-fitting procedure.

FIG. 6 is a longitudinal sectional view showing a conventional head cylinder device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed cylinder 6 Rotating cylinder 10 Cylinder main body 10a Disk part 10b Cylindrical part 10c Reinforcement rib 11 Outer ring 12 Convex part 13 Detent ridge 14 Depression groove t Magnetic tape

Claims (10)

[Claims] The present invention has a fixed cylinder and a rotary cylinder with a magnetic head which are concentrically arranged, and runs a magnetic tape along the outer peripheral surface of both cylinders to record information on the magnetic tape. In a head cylinder device for performing reproduction or erasing, etc., both or one of the two cylinders comprises a synthetic resin cylinder main body and a metal outer ring arranged on the outer peripheral surface of the cylinder main body. Has a disk portion, and a cylindrical portion integrally formed on the outer periphery of the disk portion, and a reinforcing rib is integrally formed at a corner portion between the cylindrical portion and the disk portion, and the cylindrical portion is formed. A large number of projections of minute height are formed on the entire outer peripheral surface of the portion, and between one of the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the outer ring, a detent ridge is formed on one of the outer peripheral surface and the inner peripheral surface of the outer ring. Fits on ridges for stopping A head cylinder device, wherein a concave groove that can be fitted is formed, and the outer ring is shrink-fitted to the cylindrical portion. 2. A recording medium comprising: a fixed cylinder and a rotary cylinder with a magnetic head arranged concentrically; a magnetic tape running along the outer peripheral surface of both cylinders to record information on the magnetic tape; In a head cylinder device configured to perform reproduction or erasure, both or one of the two cylinders includes a synthetic resin cylinder main body and a metal outer ring shrink-fitted on the outer peripheral surface of the cylinder main body. Characteristic head cylinder device. 3. The cylinder body comprises a disk portion and a cylindrical portion integrally formed on the outer periphery of the disk portion, wherein the outer ring is shrink-fitted on the outer peripheral surface of the cylindrical portion. The head cylinder device according to claim 2. 4. The head cylinder device according to claim 3, wherein a reinforcing rib is integrally formed at a corner between the disk portion and the cylindrical portion. 5. The head cylinder device according to claim 3, wherein a plurality of convex portions having a minute height are formed on the entire outer peripheral surface of the cylindrical portion. 6. A detent ridge is formed on one of an outer peripheral surface of the cylindrical portion and an inner peripheral surface of the outer ring,
The head cylinder device according to any one of claims 3 to 5, wherein a concave groove which can be fitted to the rotation preventing ridge is formed on the other side. 7. The head cylinder according to claim 1, wherein the cylinder body is formed of injection-molded polyphenylene sulfide, and the outer ring is formed of pressed aluminum. apparatus. 8. The head cylinder according to claim 1, wherein the cylinder main body is formed of injection-molded polyphenylene sulfide, and the outer ring is formed of extruded aluminum. apparatus. 9. The cylinder according to claim 1, wherein the cylinder body is formed of a thermosetting unsaturated polyester, and the outer ring is formed of extruded aluminum. Head cylinder device. 10. The method according to claim 1, wherein the cylinder body is formed of a thermoset unsaturated polyester, and the outer ring is formed of pressed aluminum. Head cylinder device.