JPS62279574A - Tape cartridge - Google Patents

Abstract

PURPOSE:To form a gate width required for operation of a tunnel gate by providing a tape height control rib in a position just above a tape leading-out hole on an upper case and setting the position of the tunnel gate to the front side of this rib. CONSTITUTION:A tape height control rib 14 is formed integrally at a prescribed height from the inside face of an upper wall 9 in a position just above the aperture front end of a tape leading-out hole 6 on the upper wall of an upper case 1a, and a tape guide boss 8 is formed as integrally in the end part to a pocket of the rib 14. The upper wall 9 is so stepped that a front end part 9a of the upper face of the wall 9 is slightly lower than the other part 9b, and a front cover upper wall 10a projected back from the upper end of a front cover 10 is put on the lower front end part 9a, and the upper face of the upper wall 10a and the upper face 9b of the upper case 1a are on the same plane to prevent the generation of a gap which dust penetrates from between the upper end of the front cover 10 and the front end of the upper case 1a. A front end face 9c of the upper wall 9 is formed into a slope so that it is brought into face contact with an inside face upper part 10b formed into a slope of the front cover 10.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a tape cartridge, and its main objective is to improve the moldability of its main body case.

[Conventional technology]

2. Description of the Related Art Hitherto, an audio tape cartridge of a digital recording/playback method as shown in FIGS. 7 to 10 has been known (for example, Japanese Patent Laid-Open No. 61-68785).

There, the main body case 1 is formed by abutting upper and lower plastic cases 1a and 1b and integrally connecting them with screws S or the like. Hubs 5, 5 around which the tape 4 is wound are rotatably housed above the left and right drive shaft insertion holes 3, 3 in the bottom wall 2 of the lower case lb.

On the front sides of the upper and lower cases la and 1b, tape outlet ports 6 and 6 are formed on the left and right sides, and a tape loading pocket 7 is formed at a position corresponding to between the tape outlet ports 6 and 6. A tape guide boss 8, which also serves to fasten the screw S, is formed on the side closer to the pocket 7. The tape 4 is led out from one hub 5 through a tape outlet 6 in front of the hub to a pocket 7 on the front side of the case, passes through the other tape outlet 6, and is wound onto the other hub 5 located behind it. .

A tape loading pocket 7 is formed in the bottom wall 2 of the lower case 1b at a position corresponding to the tape outlet openings 6 and 6 so as to extend into the case.

The upper part of this pocket 7 is always closed by the front end of the upper wall 9 of the upper case 1a, but the front and lower parts are open.

2. Front cover 1 for protection with tape on the front side of the main body case 1.
0 closes the front of pocket 7 and tape outlet 6, 6 (when not in use), and opens upward (when in use)
It is pivotably mounted around a rotation shaft 11 across the entire body.

Further, a shutter 12 is provided on the outer surface of the bottom wall 2 of the lower case 1b.
is attached so as to be slidable in the front-rear direction between a front closed position where the pocket 7 and the drive shaft insertion hole 3 are closed at the bottom, and a rear open position where the pocket 7 and the drive shaft insertion hole 3 are opened at the bottom. There is.

[Problems to be Solved by the Invention] The problem here is how to set the type and position of the gate of the mold when injection molding the upper case 1a of the tape cartridge.

The position of the gate ultimately affects the material flow conditions within the cavity, welding, and internal strain generation.

This is important because it governs the appearance, function, and dimensions of the upper case 1a, which is a molded product, and the moldability.

Furthermore, it is desirable to adopt a tunnel gate method as the type of gate. This is because according to the tunnel gate, the gate portion is automatically cut by shearing due to the protrusion of the molded product, and there is no need for post-processing.

Taking these points into consideration, most of the current models generally have the tunnel gate located on the side wall 13 of the upper case 1a.

However, when the gate position is set on the side wall 13 of the upper case 1a in this way, the gate marks are easily visible and spoil the appearance, leading to a decrease in commercial value.

Further, a tape guide post 8, which requires particularly high molding accuracy, is provided protruding from the front side of the upper case 1a.

In the case where the tunnel gate is attached to the side wall 13, the tape guide post 8 is far away from the gate position, making it difficult to improve the molding accuracy of the boss 8.

Furthermore, when loading the tape, the tape 4 is moved up and down within the tape outlet 6, causing unstable running.1 Also, the upper edge of the tape 4 slides against the upper edge of the opening of the tape outlet 6, causing the tape 4 to bend or be damaged. Problems such as being exposed to In order to solve this problem, a tape height regulating rib is provided on the inner surface of the upper wall 9 that closes the upper part of the tape outlet 6 on the front side of the upper case 1a to prevent the chip 14 from being bent or damaged.

One possibility is to stabilize the tape running. In such a case, it is required to improve the molding precision of this tape height regulating rib, but as mentioned above, the gate is
If it is attached to the side wall 13 far from the front side of the rib, it is not possible to sufficiently improve the molding accuracy of the rib.

This invention focuses on this fact, and by devising the positioning of the tunnel gate on the upper case, it is possible to make the gate marks less noticeable and to improve the molding accuracy of the tape height regulating rib on the front side of the upper case. The aim is to provide a tape cartridge that can.

[Means for solving problems]

As shown in FIG. 1, this invention includes upper and lower cases 1a and 1b.
A hub 5 on which the tape 4 is wound is built into the main case 1 which is made by butting the main body case 1, and tape outlets 6 are provided on the left and right sides of the front side of the main body case 1. This assumes a tape cartridge that can be pulled out to the front.

In addition, the present invention provides a tape height regulating rib 1 at a position corresponding to the upper part of the tape outlet 6 in the upper case 1a.
4, and a tunnel gate G is positioned on the front side of this rib 14.

〔Effect of the invention〕

According to the present invention configured as described above, since the gate G is positioned on the tape height regulating rib 14 provided at a position corresponding to the upper part of the tape outlet 6 in the upper case 1a, 1 the gate G can be used as a tunnel. We were able to adopt the gate. That is, the front end surface of the tape height regulating rib 14 can be sunk below the parting line PL of the mold 17 that secures the gate width required for implementing the tunnel gate G, and can be filled with the forming material from the side wall of the cavity 18. . According to this tunnel gate G, the gate part is automatically cut by shearing by the part 16a of the fixed mold 16 due to the protrusion of the upper case la, which is a molded product, so there is no need to perform cutting in post-processing. I will live. In addition, the tape height regulating rib 14 to which this gate G is attached
Since it is normally hidden by the front cover 10 and is inconspicuous, it does not spoil the appearance. moreover.

Since the tape height regulating rib 14 matches the gate position,
Since the injection pressure of the molding material is high, the molding precision of the ribs 14 can be improved.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

Since the overall structure of the tape cartridge is almost the same as the conventional one described above, the same reference numerals will be given and the explanation thereof will be omitted. 1. Only the points that are different from the tape outlet of the conventional upper case 1a will be explained. do.

A tape height regulating rib 14 is integrally molded at a predetermined height from the inner surface of the upper wall 9 at a position corresponding to the upper part of the opening light of the tape outlet 6 on the upper wall 9 of the upper case 1a. A tape guide boss 8 is integrally formed at the end of the regulating rib 14 on the side closer to the pocket 7.

In this way, the upper case 1a having the tape height regulating rib 14 and the tape guide post 8 is injection molded.
The position G is set on the front side of the tape height regulating rib 14.

At this time, as shown in FIG. 3, the front end 9a of the upper surface of the upper wall 9 of the upper case 1a is formed in a stepped shape that is slightly lower than the other portion 9b of the upper surface of the upper wall 9.

A front lid upper wall 10a that protrudes rearward from the upper end of the front lid 10 is placed on this low front end 9a so that the upper surface of the upper wall 10a and the upper surface 9b of the upper case 1a become the road surface.
This prevents a gap from forming between the upper end of the closed front cover 10 and the front end of the upper case 1a through which dust can enter. Further, the front end surface 9C of the upper wall 9 of the upper case 1a is formed as a slope so as to be exposed to the inner surface upper part 10b formed on the slope of the front cover 10.

Therefore, since the front end surface 9C of the upper wall 9 is formed as a slope in this way, the tape height regulating rib 14 is directed toward the inside of the case from the tangent T at the front circumferential surface of the boss 8, as shown in FIG. The front end surface 14. of the rib 14 is set at a position that is slightly offset by a distance a from the front end surface 9C. Secure a sufficient flat surface perpendicular to a. Thus, a tunnel gate (G) is set on the flat front end surface 14a of this tape height regulating rib 14.

As shown in FIG. 4, the tunnel gate G is designed so that the end of the runner 15 is sunk below the parting line PL of the upper movable mold 17 and the lower fixed mold 16, and the molding material is filled from the side wall of the cavity 18. do.

According to this gate G, the gate G is automatically cut by shearing of the part 16a of the fixed mold 16 as the upper case 1a, which is the product, is ejected.

At this time, the front end surface 14a of the tape height regulating rib 14 to which the tunnel gate G is attached is set at a position that is biased inward of the case from the tangent line T of the front circumferential surface of the boss 8, as described above.
Even when the front end surface 9C of the upper wall 9 of the upper case 1a is formed as a slope, the front end surface 14a of the rib 14 has a sufficient width to attach the tunnel gate G. therefore.

When automatically cutting the gate G, the gate portion on the front end surface 14a of the tape height regulating rib 14 is not scraped off or any fragments are left behind (only the gate G is
This results in a highly reliable gate that is cut cleanly from a.

Front end surface 14a and lower end surface 14b of tape height regulating rib 14
By providing chamfers 15 for relief at the corners where they intersect, a highly reliable tape height regulating rib 14 that does not add loss (3%) to the tape 4 can be obtained. By forming the lower end surface 14b of the tape height regulating rib 14 into a rounded shape, damage to the tape due to flashing can be similarly prevented.

[Another example]

As shown in FIG. 6, when the front end surface 9c of the upper wall 9 is formed on a vertical surface, the front end surface 1 of the tape height regulating rib
Even if 4a is formed so as to coincide with the tangent line T of the front part of the circumferential surface of the boss 8, it can be formed in a perpendicular flat shape with a sufficient width on the front end surface 14a.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the tape cartridge according to the present invention, in which FIG. 1 is an internal plan view of the upper case, FIG. 2 is a partial front view of the upper case, and FIG. 3 is a partial front view of the upper case. A sectional view of the tape outlet portion, and FIG. 4 is a partial sectional view of the mold for forming the upper case. FIG. 5 is a sectional view of the tape outlet portion showing another embodiment of the tape cartridge according to the present invention. FIG. 6 is a sectional view of a tape outlet portion showing still another embodiment of the tape cartridge according to the present invention. 7 to 10 show a conventional tape cartridge. FIG. 7 is an external perspective view, FIG. 8 is an internal plan view of the upper case, FIG. 9 is a perspective view of the main case and shutter, and FIG. FIG. 10 is an enlarged sectional view taken along the line A--A in FIG. 7. 1... Main body case. 1a...upper case, 1b...lower case. 4...Tape. 5...Hub. 6...Tape outlet. 9...Mud wall. 10...Front lid 1 14...Tape height regulation rib. 16...Fixed mold. 17...Movable mold. G......Tunnel gate.

Claims (1)

[Claims] Main case 1 formed by butting together upper and lower cases 1a and 1b
This tape cartridge has a built-in hub 5 around which the tape 4 is wound, tape outlet ports 66 are provided on the left and right sides of the front side of the main body case 1, and the tape 4 is drawn out from the tape outlet ports 6 to the front of the main body case 1. , a tape height regulating rib 14 is provided at a position corresponding to the upper part of the tape outlet 6 in the upper case 1a.
4. A tape cartridge characterized in that a tunnel gate G is positioned on the front side of the tape cartridge.