JPS61269214A - Rotary head assembly of magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:Not to generate a damage, an accuracy failure, etc. of a tape sliding surface of a lead groove and a lead end face of a fixed cylinder, and also to bring the fixed cylinder to a forming work by an inexpensive metallic mold, by forming the outside peripheral surface of the fixed cylinder to below a semi-cylinder, and also providing it as a separate body from a bearing mechanism for a rotary cylinder. CONSTITUTION:The outside peripheral surface of a fixed cylinder 3A is formed to below a semi-cylinder. That is to say, it is formed to below 180 deg. centering around an axis of ordinate. Therefore, as for a metallic mold for forming the outside peripheral surface having a lead groove 5, it will suffice that it is mold-released in a diameter direction 7 of the fixed cylinder, and a sink hole work of the outside peripheral surface of the fixed cylinder for reducing an abrasion against a tape-shaped recording medium, a prevention of buckling of the tape-shaped recording medium, and a formation of the fixed cylinder having a theft of a lead end face for preventing an abrasion of the lead end face can be executed. Also, since a bearing mechanism 4A of a rotary cylinder and the fixed cylinder 3A are provided as separate bodies, the respective forming metallic molds become simple and inexpensive, and also the metallic mold can be worked easily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvements in the formation of a rotary head assembly for a magnetic recording and reproducing device, particularly a fixed cylinder thereof.

[Conventional technology]

The rotary head assembly of the conventional magnetic recording/reproducing device is the fifth
It is constructed as shown in FIG. 6 and FIG. @Figure 5 is a perspective view, and Figure 6 is an enlarged vertical sectional view of Figure 5. In the figure, (1) is a tape-shaped recording medium such as a videotape (
A magnetic head for recording and reproducing information on (magnetic tape) is attached to a rotating cylinder (2). (3) is a fixed cylinder equipped with a bearing mechanism (4) that supports the rotary cylinder (2), and has a lead groove (5) on its outer peripheral surface that guides the running of the tape-shaped recording medium. Note that (6) is a tape-shaped recording medium.

Recently, a method of molding the stationary cylinder from plastic material or the like has been used because it is easy to process and inexpensive. Therefore, the lead groove that guides the tape-shaped recording medium of the fixed cylinder is lined with sink marks to reduce friction between the tape-shaped recording medium and the fixed cylinder, and the lead groove guides the tape-shaped recording medium. The lead end face is provided with a recess extending inward from the surface of the fixed cylinder in order to prevent buckling of the tape-shaped recording medium and prevent abrasion between the tape-shaped recording medium and the lead end face.

[Problem that the invention seeks to solve]

Conventional fixed cylinders are constructed as described above, so when molding them, it is difficult to release the mold.
There are problems in that the tape sliding surface force in the lead groove, damage to the lead end face, poor precision, etc. occur frequently, and the mold is complicated and expensive.

This invention was made to solve the problems of the conventional products, and it is possible to mold a fixed cylinder using an inexpensive mold without causing damage to the tape sliding surface of the lead groove and the lead end face, or poor precision. It is an object of the present invention to provide a magnetic recording and reproducing device that allows the recording and reproducing information to be read.

[Means for solving problems]

A rotary head assembly for a magnetic recording/reproducing device according to the present invention has a fixed cylinder whose outer circumferential surface is a semicircular cylinder or less, a bearing mechanism for the rotary cylinder that is formed separately from the fixed cylinder, and a bearing mechanism for the rotary cylinder that is separate from the fixed cylinder. A positioning means is provided for positioning both at predetermined relative positions.

[Effect]

The rotary head assembly of the magnetic recording/reproducing device according to the present invention has the outer circumferential surface of the fixed cylinder made smaller than a semi-cylindrical cylinder, and the bearing mechanism of the rotary cylinder is formed separately from the fixed cylinder, so that the mold can be adjusted to the diameter of the fixed cylinder. The fixed cylinder and the bearing mechanism can be molded with a simple mold, respectively.
Furthermore, by providing the positioning means, the accuracy of the combination of the fixed cylinder and the bearing mechanism can be maintained at the same level as that of conventional integral molding.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Fig. 1 is a perspective view, Fig. 2 is an enlarged vertical sectional view of Fig. 1, Fig. 3 is a perspective view of the fixed cylinder, and Fig. 4 is a perspective view of the bearing mechanism. are given the same reference numerals and their explanation will be omitted.

In the figure, (3A) is a bearing mechanism for a fixed cylinder, and (4A) is a bearing mechanism for a rotating cylinder (2), which are each formed separately as shown in FIGS. 3 and 4. The outer peripheral surface of the fixed cylinder (3A) is formed into a semi-cylindrical shape or less. That is, the conventional shape was completely cylindrical, but the angle is now less than 180° around the vertical axis. By doing this, the mold that forms the outer circumferential surface having the lead groove (5) only needs to be released in the radial direction (7) of the fixed cylinder, and it is necessary to release the mold in the radial direction (7) of the fixed cylinder. It is possible to form a fixed cylinder having sink marks on the outer surface of the fixed cylinder, and a recess on the lead end face for preventing buckling of the tape-shaped recording medium and preventing wear of the lead end face. Moreover, the rotating cylinder bearing mechanism (4A)
By separating the mold and the fixed cylinder (3A), each mold becomes simpler and cheaper, and the mold is easier to process, which improves the accuracy of the linearity of the lead groove (5). .

(8) is a positioning means for positioning the fixed cylinder (3A) and the bearing mechanism (4A) at a predetermined relative position,
Axial holes (801) and (802) formed in the axially overlapping portion of the fixed cylinder (3A) and the fixed cylinder (4A) so as to align with each other at the predetermined relative positions.
and a pin (803) inserted into the axial holes (801) and (802) across the fixed head (3A) and the bearing mechanism (4A). Such positioning means (8)
By providing this, even though the fixed cylinder (3A) and the bearing mechanism (4A) are formed as separate bodies, the accuracy of their combination can be maintained at the same level as that of conventional integral molding.

In the above embodiment, the positioning means is a fixed cylinder (3
A) and the axial hole (801) formed in the bearing mechanism (4A).
), (802) and a pin (803) inserted into this, but the pin (803) is either insert molded into either the fixed head (3A) or the bearing mechanism (4A), or is integrally formed. Alternatively, an axial hole may be formed on the other side and the pin may be inserted into the hole.

〔Effect of the invention〕

As described above, according to the present invention, by making the outer circumferential surface of the fixed cylinder smaller than a semi-cylindrical cylinder and making it separate from the bearing mechanism for the rotating cylinder, the tape sliding surface of the lead groove of the fixed cylinder and The fixed cylinder can be molded using an inexpensive mold without causing damage to the lead end face or poor precision, etc. Because the mold processing is easy, the accuracy of the linearity of the lead groove is improved, and the large size due to molding is It becomes possible to produce lids, and by providing positioning means for the fixed cylinder and the bearing mechanism, the accuracy of the combination of these two can be maintained at the same level as that of conventional integral molding, and effects such as hanging can be achieved.

[Brief explanation of the drawing]

Figure 1 is a perspective view of an embodiment of the present invention, Figure 2 is an enlarged vertical sectional view of Figure 1, Figure 3 is a perspective view of the fixed cylinder in the embodiment of Figure 1, and Figure 4 is a bearing. A perspective view of the mechanism;
Figure 9s5 is a perspective view of a conventional rotary head assembly, No. 6
The figure is an enlarged longitudinal sectional view of FIG. 5. In Figure 2, (1) is a magnetic head, (2) is a rotating cylinder, (3A) is a fixed cylinder, (4A) is a bearing mechanism, (
6) is a tape-shaped recording medium, (8) is a positioning means, (8) is a tape-shaped recording medium; (8) is a positioning means;
01) and (802) are axial holes, and (803) is a pin. The same reference numerals in each figure represent the same or equivalent parts. Agent Patent Attorney Masuo Oiwa Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Procedural amendment (voluntary) 1. Indication of case Japanese Patent Application No. 111028/1983 Assembly 3, Amendment Patent applicant 5, Claims column of the specification to be amended, Detailed explanation of the invention column 6 of the specification, Contents of the amendment: 1) Claims of the specification attached Correct as follows. '2) "Fixed head" in lines 8 and 9 of page 7 of the specification is corrected to "fixed cylinder."'3)"Fixed spatula F" on page 7, line 20 is corrected to "fixed cylinder." The attached appended claims (1) A rotating cylinder that holds a magnetic head, a bearing mechanism that rotatably supports this rotating cylinder, and a fixing device that holds this bearing mechanism and guides a tape-shaped recording medium on its outer peripheral surface. In a rotary head assembly of a magnetic recording and reproducing device including a cylinder, the outer circumferential surface of the fixed cylinder is made less than or equal to a semi-cylindrical cylinder, and the bearing mechanism is formed separately from the fixed cylinder, and the bearing mechanism and the fixed cylinder are separated from each other. A rotary head F assembly for a magnetic recording/reproducing device, characterized in that a positioning means for positioning both of these at a predetermined relative position is provided. (2) The positioning means includes an axial hole formed in the axially overlapping portion of the fixed cylinder and the bearing mechanism so as to be aligned with each other at a predetermined relative position between the fixed cylinder and the bearing mechanism; A rotating head F assembly for a magnetic recording/reproducing device according to claim 1, comprising a pin inserted across the rotating head F assembly of a magnetic recording/reproducing device. (3) The positioning means is configured to position an axial pin fixed to either one of the fixed cylinder and the bearing mechanism at a predetermined relative position between the fixed cylinder and the bearing mechanism at the axial overlap part of the fixed cylinder and the bearing mechanism/structure. 2. A rotary head assembly for a magnetic recording and reproducing apparatus as claimed in claim 1, comprising an axial hole formed in the other of the fixed cylinder and the bearing mechanism so as to align with said pin and allow said pin to be inserted therein. (4) A rotary header assembly for a magnetic recording/reproducing device according to any one of claims 1 to 3, characterized in that the fixed cylinder and the bearing mechanism are molded.

Claims (4)

[Claims] (1) A magnetic recording and reproducing device equipped with a rotating cylinder that holds a magnetic head, a bearing mechanism that rotatably supports this rotating cylinder, and a fixed cylinder that holds this bearing mechanism and guides a tape-shaped recording medium on its outer peripheral surface. In the rotating head assembly, the outer peripheral surface of the fixed cylinder is made into a semi-cylindrical shape or less, the bearing mechanism is formed separately from the fixed cylinder, and the fixed cylinder and the bearing mechanism are further positioned at predetermined relative positions. 1. A rotary head assembly for a magnetic recording/reproducing device, characterized in that a positioning means is provided for positioning the head. (2) The positioning means includes an axial hole formed in the axially overlapping portion of the fixed cylinder and the bearing mechanism so as to be aligned with each other at a predetermined relative position between the fixed cylinder and the bearing mechanism, and a fixed head and the bearing mechanism inserted into the axial hole. 2. A rotary head assembly for a magnetic recording/reproducing apparatus according to claim 1, comprising a pin inserted across the magnetic recording and reproducing apparatus. (3) The positioning means includes an axial pin fixed to either one of the fixed head and the bearing mechanism at the axial overlap portion of the fixed cylinder and the bearing mechanism, and a positioning means that connects the pin at a predetermined relative position between the fixed head and the bearing mechanism. 2. A rotary head assembly for a magnetic recording and reproducing apparatus as claimed in claim 1, comprising a fixed head and an axial hole formed in the other side of the bearing mechanism so as to allow the pin to be inserted therein in alignment. (4) A rotary head assembly for a magnetic recording/reproducing device according to any one of claims 1 to 3, characterized in that the fixed cylinder and the bearing mechanism are molded.