JPH04318358A - Tape guide drum device - Google Patents

Abstract

PURPOSE:To enable mass production without worsening rotational accuracy by reducing the number of manpower in adjustment and to obtain the tape guide drum device with high performance at low cost. CONSTITUTION:The device is equipped with a magnetic head 55, a rotary disk 62 having a bearing part 66 and a rotary drum means for guiding a magnetic tape. Then, after fixing the rotary drum means to the rotary disk 62 by using at least one fixing means, a bearing part 80 of the rotary disk 62 and a magnetic tape guide surface 58 of the rotary drum means are simultaneously processed, and after obtaining required accuracy, they are combined with the side of a fixed drum means.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape guide drum device that is effective for use in a magnetic recording and reproducing device for recording and reproducing signals.

0002

2. Description of the Related Art In recent years, as the demand for video tape recorders has increased, higher performance and lower cost video tape recorders have been required. Moreover, video cameras with integrated cameras are required to be smaller and lighter. Therefore, tape guide drum devices are also required to have multiple heads, be smaller in size, and reduce costs.

An example of the above-mentioned conventional tape guide drum device will be described below with reference to the drawings.

FIG. 3 is a sectional view showing the structure of a conventional tape guide drum device. To explain this structure and operation, first, the upper cylinder 10 and the disk 12 are individually machined to obtain the required precision. At this time, a gap S is provided between the upper cylinder 10 and the disc 12 in order to enable centering adjustment. A main shaft 16, a stator unit 20, and a fixed rotary transformer 22 are coaxially fixed to the lower cylinder 14.

The radial bearing portion 30 of the disk 12, on which the rotating rotary transformer 18 and the rotor magnet unit 24 are coaxially fixed, is inserted into the main shaft 16, and the thrust bearing member 32 is fixed to the disk 12, forming a fluid bearing portion and allowing free rotation. is maintained. After that, the magnetic head 5
The upper cylinder 10, which is fixed with It is fixed with screws.

[0006]

[Problems to be Solved by the Invention] However, with the above configuration, (1) centering adjustment takes a long time, (2) the relative positions of the components shift due to the screw rotation torque when screwing. 3) There was a problem in that the pressure applied during centering adjustment had the effect of tilting the bearing and main shaft, impairing rotational accuracy.

In view of the above problems, the present invention provides a tape guide drum device that reduces the number of adjustment steps and does not impair rotational accuracy.

[0008]

[Means for Solving the Problems] In order to solve the above problems, a tape guide drum device of the present invention is provided with a magnetic head, a rotating disk having a bearing portion, and a rotating drum means for guiding a magnetic tape. After fixing the rotating drum means to the rotating disk using at least one fixing means, the bearing part of the rotating disk and the magnetic tape guide surface of the rotating drum means are simultaneously machined, and after obtaining the required accuracy, the fixed drum means side is machined. It has a configuration that allows for combinations.

[0009]

[Function] The present invention reduces the number of adjustment steps and enables mass production without sacrificing rotational accuracy, and provides a high-performance, inexpensive tape guide drum device.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS A tape guide drum device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the configuration of a tape guide drum device according to an embodiment of the present invention, and FIG. 2 is a sectional view showing the main parts of the device. To explain this structure and operation, first, a cutting allowance (not shown) for finishing is provided in advance for the bearing portion 80 of the disk 62 and the tape guide surface 58 of the upper cylinder 60. At this time, the upper cylinder 60 and the disk 62 are engaged with each other with only a slight gap. Upper cylinder 60 to disk 62
After fixing with screws 61 to form an upper cylinder unit, the bearing part 80 and tape guide surface 58 are finished simultaneously to obtain the necessary accuracy. The screw fixing force is sufficient to prevent the coaxiality of the disk 62 and the upper cylinder 60 from shifting due to machining, assembly process, impact, etc. The upper cylinder unit inserts the bearing part 80 into the shaft 66 fixed to the lower cylinder 64, fixes the thrust bearing member 82, forms a fluid bearing part, and becomes rotatable.

[0012] In this way, the tape guide surface has a configuration in which rotational runout accuracy can be easily obtained without any adjustment, and mass productivity is improved.

Furthermore, even in a structure in which the shaft 66 is fixed to the disk 62 by a method such as shrink fitting, and a bearing part is provided on the lower cylinder 64 side, the tape guide surface can be cut based on the shaft to obtain the necessary accuracy. Can be done.

Furthermore, after the magnetic head 55 and the rotor magnet 74 are attached, the upper cylinder 60 may be deformed by the fixing force, so as shown in FIG. , deformation can be prevented by providing a portion t2, where t2<t1, around the entire circumference of the fixed portion slightly on the outer circumference side.

Further, the effect of the upper cylinder unit will be further improved if the bearing portion 80 and tape guide surface 58 are finished after the magnetic head 55 and rotor magnet 74 are attached.

[0016]

[Effects of the Invention] As described above, the present invention reduces the number of adjustment man-hours, enables mass production without sacrificing rotational accuracy, and achieves high performance.
This has the effect of providing an inexpensive tape guide drum device.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a tape guide drum device in an embodiment of the present invention.

[Figure 2] Cross-sectional view showing the main parts of the device

[Fig. 3] Cross-sectional view showing a conventional tape guide drum device

[Explanation of symbols]

60 Upper cylinder 62 Disc 64 Lower cylinder 66 Shaft

Claims (4)

[Claims] 1. A rotary disk comprising a magnetic head and a bearing portion, and a rotary drum means for guiding a magnetic tape, the rotary drum means being fixed to the rotary disk using at least one fixing means. The tape guide drum device is characterized in that the bearing portion of the rotary disk and the magnetic tape guide surface of the rotary drum means are subsequently machined at the same time, and after the necessary precision is obtained, they are combined with the fixed drum means side. 2. The tape guide drum device according to claim 1, wherein the bearing portion is a fluid bearing portion, and the rotating disk is integrally formed with a radial bearing member made of a rigid body that can be plastically worked. [Claim 3] The rotating disk has a main shaft coaxially fixed,
2. The tape guide drum device according to claim 1, wherein the magnetic tape guide surface of the rotary drum means is machined based on the main axis to obtain necessary accuracy. 4. The rotating drum means is configured such that, with respect to the thickness t1 of the rotating disk fixing location, there is a portion having a thickness t2 over the entire circumference from the fixing location to the outer circumferential side where t1>t2. Item 1. Tape guide drum device according to item 1.