JPS6317074Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a magnetic sheet that magnetically records a plurality of information signals in an annular track shape. This is an improved version of the mounting mechanism.

The applicant of the present invention has proposed a structure as shown in FIG. 1 as one of the magnetic sheet jackets in which this type of magnetic sheet is rotatably housed in the jacket. The magnetic sheet housed in this jacket is constructed by attaching a center core 3 formed into a cylindrical shape from a plastic material or the like into a center hole 2 of a magnetic sheet body 1 formed into a disk shape. That is, the magnetic sheet body 1 has the center hole 2
The circumferential portion 2A of the center core 3 is bonded and fixed onto the flange portion 4 protruding from the outer periphery of the middle portion of the center core 3, and an annular yoke 6 is bonded within the annular recess 5 formed on one end surface 3A of the center core 3. It is fixed with adhesive. The yoke 6 attracts a chuck magnet provided at a position corresponding to the yoke 6 on the reel stand on the side of the magnetic recording apparatus to obtain a driving force for the reel stand.

By the way, in the above configuration, since the center core 3 and the magnetic sheet body 1 and the center core 3 and the yoke 6 are fixed with adhesive, the adhesive may protrude during assembly, or the adhesive may Problems such as deterioration of adhesive strength due to chemical changes are likely to occur, and the workability of assembly is also poor.

Therefore, an object of the present invention is to solve the above-mentioned conventional drawbacks and to provide a magnetic sheet that is simple in structure and easy to manufacture and process.

Another object of the present invention is to make it possible to fix the center core and the yoke without using adhesives or increasing the number of parts as in the prior art.

In other words, the present invention provides for the shaft end surface of the center core attached to the rotation center of the magnetic sheet body.
A metal ring is attached to the center core by press-fitting a plurality of protrusions protruding from the circumference of a metal plate formed into an annular shape and bent in the axial direction.

The present invention will be described below with reference to embodiments shown in FIGS. 2 to 4.

First, in this embodiment, the center core 30 is
A flange portion 31 is provided protrudingly from one end in the axial direction, the circumferential portion of the center hole 2 of the magnetic sheet body 1 is placed on the upper surface 31a of the flange portion 31, and an annular protrusion is provided on the lower surface 31b of the flange portion 31. A portion 32 is provided in a protruding manner, and its tip 32a serves as a reference surface for attachment to a magnetic recording device (not shown).

Further, in the axial direction of the central portion, a drive shaft insertion hole 3 into which a rotational drive shaft of a magnetic recording device (not shown) is inserted and engaged.
3 is formed through it. Further, the yoke 60 is
It is formed as an annular plate made of a magnetic plate, and in this example, press-fit claws 61A, 61B, 61C, and 61D are provided to protrude in the axial direction from the inner peripheral edge 60A. The press-fit claws 61A to 61D are connected to the core 30 when the yoke 60 is fitted into the mounting recess 34 of the center core 30.
This is the part that becomes the press-fit locking part.

In addition, the press-fit claws 61A to 61D of the yoke 60
As shown in FIG. 4, they are not only disposed on the inner circumferential edge 60A side, but may also be disposed on the outer circumferential edge 60B, or may be disposed on both the inner and outer circumferential edges.

Further, each of the press-fit claws 61A to 61D can be easily inserted into the core 30 by forming a sharp protrusion toward the tip 162 of the claw body 61 as shown in FIG. 5, or as shown in FIG. 6A. The body 61 is formed as a rectangular tongue piece, which is press-fitted into a press-fit pilot hole (not shown) formed in the core 30, and twisted around its axis as shown in FIG. 6B, thereby making the press-fit state strong. can. Further, if the pilot hole provided in the core 30 into which the claw body 61 (not shown) is press-fitted is a tapered hole, or if it is formed to have a slightly narrower width than the claw body 61, a strong bond can be easily obtained.

In the above configuration, the attachment of the yoke 60 to the center core 30 can be realized by press-fitting and locking a press-fit claw in the annular recess 34 provided at one end of the core 30 in the axial direction. There is no need to use it, and a secure installation can be easily achieved.

As described above, in the present invention, the center core attached to the center of rotation of the magnetic sheet body and the yoke can be easily assembled and fixed in a stable state by a simple operation.

In particular, when the magnetic sheet jacket is housed and used in a device whose overall shape is small enough to fit on the palm of the hand, the shape of the center core and yoke is inevitably formed into a small size of several millimeters. Therefore, the assembly process can be simplified in the present invention, which can be achieved by simply engaging by press-fitting, without using an adhesive unlike the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing a conventional example, FIGS. 2 to 6 are views showing an embodiment of the present invention, FIG. 2 is a bottom view of the center core, and FIG. 3 is a sectional view, and FIG. Figure 4 shows the yoke, with A being a plan view and B being a side view. FIG. 5 is an enlarged perspective view of a press-fitting claw, FIG. 6 is an example of another press-fitting claw, A is an enlarged perspective view of the main part, and B is a perspective view showing the processing state at the time of attachment. 1... Magnetic sheet, 30... Center core, 3
1... Flange portion, 32... Annular protrusion, 60...
Yoke, 61...Claw body, 61A, 61B, 61
C, 61D...Press-fitting claw.

Claims (1)

[Scope of utility model registration request] A plurality of protrusions protruding from the periphery of a metal plate formed in an annular shape and bent in the axial direction are press-fitted onto the shaft end surface of the center core, which is attached to the center of rotation of the magnetic sheet body. A magnetic sheet with a metal ring attached.