JPH0538457Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a tape reel built into a tape cartridge, and improves the structure of the spring bearing part that is located at the center of the upper end face in the central axis direction and receives the spring pressure of the pressure leaf spring.

[Conventional technology]

This type of plastic tape reel generally has a spring receiving projection 15 integrally formed in the center of the upper end surface of the reel body 3, as shown in FIGS. 3 and 4.

This tape reel is rotatably incorporated inside the tape cartridge. At this time, the tape reel receives the reel pressing spring S mounted inside the tape cartridge with the spring receiving protrusion 15, so that the tape cartridge can be rotated. It is regulated internally to prevent it from unintentionally rattling in the thrust direction, and is pressed against the drive shaft of the drive when loaded into the drive.

The spring receiving projection 15 is required to have extremely little wear due to friction with the reel presser spring S when the tape reel rotates at high speed, and for this reason, materials such as polyacetal, which have relatively excellent wear characteristics, are often used.

However, since this spring receiving protrusion 15 is integrally molded with the reel body 3, the material of the reel body 3 is limited to the required characteristics of the spring receiving protrusion 15, and the characteristics exceed the required characteristics of the material of the reel body 3. The problem was that expensive materials had to be used.

As a countermeasure against this problem, various methods have been proposed and implemented in which the spring receiving piece 2 is molded from a different material separately from the reel body 3 and assembled to the reel body 3.

A typical example is the form shown in FIG.
In this case, a piece flange 10 with a spring receiving protrusion 11 protruding from the center of the upper surface is used as the spring receiving piece 2, a leg portion 12 is provided protruding from the center of the lower surface of the piece flange 10, and the leg portion 12 is reeled. It is inserted into and connected to the center hole 8 of the upper flange 4 fixed to the body (Japanese Utility Model Publication No. 101381/1981).

[Problem that the invention attempts to solve]

However, it has been found that the conventional spring receiving piece 2 is easily deformed or cracked by the impact of an accidental drop of the tape cartridge. This is because when an impact load is applied from the arrow W to the spring receiving piece 2 due to a falling impact, stress is concentrated at the part of the piece flange 10 where it contacts the upper end opening edge E of the center hole 8 of the reel upper flange 4. Due to this stress concentration, the piece flange 10 undergoes bending deformation as shown by the two-dot chain line A in FIG. In particular, when the gate G is positioned on the piece flange 10, this gate part has a large residual stress and is easily distorted, so cracks are likely to occur in the piece flange 10 starting from the gate part due to the impact load. .

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a tape reel in which a separate spring receiving piece can be easily positioned and attached to the reel upper flange fixed on the reel body by push-fitting from above.

Another object of the present invention is to obtain a tape reel in which the spring receiving piece has excellent impact resistance and the piece flange is less likely to undergo bending deformation.

[Means to solve the problem]

In order to achieve the above object, the tape reel of the present invention has the following features: a reel upper flange 4 is fixed on the upper end surface of the reel body 3 in the central axis direction, as shown in FIG. , the piece flange 10
Spring receiving protrusion 1 protruding upward from the center of the top surface
1, and an elastically deformable leg part 12 which protrudes downward from the center of the lower surface of the piece flange 10 and has a non-return claw part 13 on the outer periphery of the lower end. A center hole 8 is opened at the center of the flange 4, and an upwardly expanding tapered surface 9 is formed on the inner periphery of the upper opening edge of the center hole 8. It is fitted into the center hole 8 of the reel upper flange 4 from above in a manner that prevents it from coming off, and the outer diameter d of the base of the spring receiving projection 11 with the piece flange 10 is set so that the upper end of the center hole 8 is open. The content is that the hole diameter is set larger than the hole diameter D.

[Effect]

With the reel upper flange 4 fixed to the reel body 3, the spring receiving piece 2 can be attached later. That is, the spring receiving piece 2 is connected to the sled leg portion 12.
from above and fit into the center hole 8 on the reel upper flange 4 side. At this time, since the leg portion 12 is elastically deformable and has a tapered surface 9 formed on the inner periphery of the upper opening edge of the center hole 8, the leg portion 12 can be easily guided and fitted into the center hole 8. I can do it. A non-return claw portion 13 provided on the outer periphery of the lower end of the leg portion 12 is inserted into the center hole 8 of the leg portion 1.
To prevent the entire spring receiving piece 2 from coming off upward when the pieces 2 are completely fitted.

When the spring receiving piece 2 is installed, the spring receiving protrusion 11 has a large diameter and is in a state where it straddles the center hole 8. Therefore, even if an impact load is applied to the spring receiver piece 2 as indicated by the arrow W in FIG. will receive. That is, although the piece flange 10 of the spring receiving piece 2 is received around the center hole 8 on the upper surface of the reel upper flange 4, the impact load is not applied only to the piece flange 10.

[Effect of idea]

According to this invention, the outer diameter d of the base of the spring receiving protrusion 11 with the piece flange 10 is set to be larger than the upper end opening diameter D of the center hole 8 of the reel upper flange 4. It is possible to effectively and reliably prevent deformation and cracks of the piece flange 10, which are likely to occur due to this, and increase the strength. In actual prototype production, it was confirmed that the strength could be increased approximately 20 times compared to the conventional example shown in Figure 5. Moreover, since the center hole 8 of the reel upper flange 4 has a tapered surface 9 formed on the inner periphery of the upper opening edge thereof, the leg portion 12 of the spring receiving piece 2 also utilizes the elastic deformation of the center hole 8. It can be easily positioned and pushed into the center hole 8 from above, and when this fitting is installed, the non-return claw part 1 on the outer periphery of the lower end of the leg part 12
3 simultaneously prevents the spring receiving piece 2 from coming off upward, and the assembly work is also easy.

〔Example〕

1 and 2 show an embodiment of the invention.

In FIG. 2, 1 is a tape reel molded from a plastic material such as polystyrene, and 2 is a spring receiving piece assembled to the tape reel 1.

The tape reel 1 consists of a reel body 3 with a lower flange and a reel upper flange 4 fixed to the upper end of the reel body 3. The reel body 3 is formed into a double cylinder shape with a drive shaft hole 5 that is open at the bottom.
The upper end of the drive shaft hole 5 is closed with a blind wall 6. A lower flange 7 is integrally formed on the outer periphery of the lower end of the reel body 3. The reel upper flange 4 is stacked on the upper surface side of the blind wall 6 of the reel body 3 and integrally joined by caulking welding or the like, and a center hole 8 is opened in the center of the upper flange 4.
A tapered surface 9 with an upwardly expanding shape is formed on the inner periphery of the upper end opening edge so that a leg portion 12 of a spring receiving piece 2, which will be described later, can be easily inserted. Note that the manner in which the reel upper flange 4 is fixed to the reel body 3 does not matter.

The spring receiving piece 2 is a plastic molded product made of polyacetal or the like, and includes a piece flange 10,
The flange 10 has a spring receiving projection 11 projecting upward from the center of the upper surface, and a leg portion 12 projecting downward from the center of the lower surface of the flange 10.

The spring receiving protrusion 11 is formed in a chevron-shaped cross section, and the cross section of the base part with the piece flange 10 is as follows.
The outer diameter d of the base is set to the center hole 8 of the reel upper flange 4 so that the cross-sectional shape is wider in the radial direction than the upper end opening diameter D of the reel upper flange 4.
It is set larger than the upper end opening diameter D of.

The leg portion 12 is formed into a cylindrical shape that is elastically deformable in the radial direction, and its outer diameter is set to be approximately the same as the minimum inner diameter of the center hole 8 of the reel upper flange 4, and a non-return check is provided on the outer periphery of the lower end of the leg portion 12. It has a claw part 13.

The spring receiving piece 2 thus formed is assembled in a manner to prevent it from coming off by press-fitting the non-return claw part 13 of the leg part 12 into the center hole 8 of the reel upper flange 4 from above through its elastic deformation.

In such a case, even when a drop impact load is applied to the piece flange 10 of the spring receiving piece 2, the spring receiving protrusion 11 has a cross section expanded radially outward from the upper end opening diameter D of the center hole 8. As a result of receiving an impact load, stress concentration occurs in the piece flange 10 at the contact point between the upper end surface 4a of the reel upper flange 4 (the seat surface that receives the piece flange 10) and the upper end opening edge E where the tapered surface 9 intersects. As a result, the test results showed that the piece flange 10 was completely free from bending deformation and cracking.

[Brief explanation of the drawing]

1 and 2 show an embodiment of a tape reel according to the present invention, with FIG. 1 being an enlarged cross-sectional view of the main parts, and FIG. 2 being a longitudinal cross-sectional view of the entirety. 3 and 4 show a conventional tape reel, with FIG. 3 being a perspective view and FIG. 4 being a longitudinal sectional view.
FIG. 5 is a sectional view of main parts showing another conventional example. 1...Tape reel, 2...Spring receiver piece,
3... Reel body, 4... Reel upper flange,
8... Center hole, 9... Tapered surface, 10... Piece flange, 11... Spring receiving protrusion, 12... Leg portion, d... Outer diameter of the base of the spring receiving protrusion, D...
...Opening diameter at the top of the center hole.

Claims (1)

[Claims for Utility Model Registration] A reel upper flange 4 is fixed on the upper end surface of the reel body 3 in the direction of the central axis, and a piece flange 10;
Spring receiving protrusion 1 protruding upward from the center of the top surface
1, and an elastically deformable leg part 12 which projects downward from the center of the lower surface of the piece flange 10 and has a non-return claw part 13 on the outer periphery of the lower end. A center hole 8 is opened at the center of the flange 4, and an upwardly expanding tapered surface 9 is formed on the inner periphery of the upper opening edge of the center hole 8. It is fitted into the center hole 8 of the reel upper flange 4 from above in a manner that prevents it from coming off, and the outer diameter d of the base of the spring receiving projection 11 with the piece flange 10 is the upper end opening diameter D of the center hole 8. A tape reel characterized by being set larger than the .