JPH0734300B2 - Tape car ledge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a tape cartridge, and its main purpose is to improve the moldability of the main body case.

[Prior Art] Conventionally, an audio tape cartridge of a digital recording / reproducing system as shown in FIGS. 7 to 10 has been known (for example, Japanese Patent Laid-Open No. 61-68785). Where,
The body case 1 is made of plastic upper and lower cases 1a and 1b.
Are butted against each other and integrally coupled with a screw S or the like. Hubs 5, 5 around which the tape 4 is wound are rotatably accommodated in the left and right drive shaft insertion holes 3, 3 of the bottom wall 2 of the lower case 1b.

On the front side of the upper and lower cases 1a and 1b, tape outlets 6 and 6 are formed on the left and right sides, and a tape loading pocket 7 is formed at a position corresponding to the tape outlets 6 and 6, respectively. A tape guide boss 8 which is also used for fastening the screw S is formed on the side closer to the pocket 7. The tape 4 is led out from one hub 5 to a pocket 7 on the front side of the case through a tape outlet 6 in front of the hub 5.
The tape is taken up via the other tape pull-out port 6 and wound on the other hub 5 located behind it.

The tape loading pocket 7 is formed so as to enter the inside of the case at a position corresponding to the space between the tape outlets 6 on the bottom wall 2 of the lower case 1b, and the upper side of the pocket 7 is the upper wall 9 of the upper case 1a. It is always closed at the front end of the, but its front and lower sides are open.

Then, a front cover 10 for protecting the tape is provided on the front side of the main body case 1.
Is pivotally mounted about a pivot shaft 11 in a posture of closing the front of each of the pocket 7 and the tape outlets 6 (when not in use) and an upward posture of opening (in use).

Further, on the outer surface side of the bottom wall 2 of the lower case 1b, a shutter 12 closes the pocket 7 and the lower part of the drive shaft insertion hole 3 at the front closed position, and opens the pocket 7 and the lower part of the drive shaft insertion hole 3 respectively. It is mounted so as to be slidable in the front-back direction across the rear open position.

[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 is important because it finally influences the flow condition of the material in the cavity, the weld, and the generation of internal strain, and controls the appearance, function, size, and formability of the upper case 1a as a molded product.

In addition, it is desirable to adopt the tunnel gate method as the type of gate. This is because the tunnel gate automatically cuts the gate portion due to shearing due to the protrusion of the molded product, and there is no need for post-processing.

Considering these points, in most cases, the tunnel gate position is currently set 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 manner, the gate mark is easily noticed, which impairs the appearance and lowers the commercial value. Further, a tape guide boss 8 which requires a particularly high molding accuracy is provided on the front side of the upper case 1a. However, in the case where a tunnel gate is attached to the side wall 13, the tape guide boss 8 moves away from the gate position. It is difficult to improve the molding accuracy of the boss 8.

Further, when the tape is loaded, the tape 4 is moved up and down in the tape outlet 6 to cause unstable running, and the upper edge of the tape 4 slides on the upper edge of the opening of the tape outlet 6 to break or damage the tape 4. Problems such as being received occur. 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 tape 4 from being broken or damaged.
It is considered to stabilize the tape running. In such a case, it is required to improve the forming accuracy of the tape height regulating ribs, but as described above, if the gate is attached to the side wall 13 away from the front side of the upper case 1a, the forming accuracy of the ribs will be sufficient. Can not be raised.

This invention focuses on such a fact, and devises the position setting of the tunnel gate of the upper case so that the gate mark is not conspicuous, and the forming accuracy of the tape height regulation rib on the front side of the upper case is improved. The present invention aims to provide a tape cartridge that can be used.

[Means for solving problems]

As shown in FIG. 1, this invention incorporates a hub 5 around which a tape 4 is wound around a main body case 1 formed by abutting upper and lower cases 1a and 1b, and tape outlets 6 and 6 are provided on the left and right of the front side of the main body case 1. It is assumed that the tape cartridge is provided so that the tape 4 can be pulled out from the tape outlet 6 to the front of the main body case 1.

In addition, the present invention is such that a tape height regulating rib 14 is provided at a position corresponding to the upper portion of the tape outlet 6 in the upper case 1a, and the tunnel gate G is set on the front side of the rib 14.

〔The invention's effect〕

According to the present invention configured as described above, the gate G is set on the tape height regulating rib 14 provided at a position corresponding to the upper portion in the tape outlet 6 of the upper case 1a. We came to be able to adopt tunnel gate. That is, the front end face of the tape height regulating rib 14 can have a height enough to secure the gate width required for implementing the tunnel gate G, and the end of the runner R is fixed as shown in FIG. The forming material can be filled from the side wall of the cavity 18 by sinking from the parting line PL of the mold 16 and the movable mold 17. According to this tunnel gate G, the gate portion is automatically cut by the shearing by the part 16a of the fixed mold 16 due to the protrusion of the upper case 1a, which is a molded product, and therefore the cutting work is not necessary in the post-processing. It will be saved. Further, since the tape height restricting rib 14 to which the gate G is attached is hidden by the front lid 10 in the state, the appearance is not spoiled. Furthermore, since the tape height regulating rib 14 matches the gate position, the injection pressure of the molding material is high and the molding accuracy of the rib 14 can be improved.

〔Example〕

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

Since the overall structure of the tape cartridge is substantially the same as the conventional one described above, the same reference numerals are given and the description thereof will be omitted, and only the points different from the conventional tape outlet portion of the upper case 1a will be described. To do.

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

As described above, the upper case 1a having the tape height regulating rib 14 and the tape guide boss 8 is injection-molded. At the time of this molding, the position of the tunnel gate G of the die is the tape height regulating rib 14a. Set on the front side.

At this time, as shown in FIG. 3, the front end portion 9a of the upper surface of the upper wall 9 of the upper case 1a is formed in a step-down shape so as to be slightly lower than the other portion 9b of the upper surface of the upper wall 9a. Front lid on 9a
A front lid upper wall 10a protruding rearward from the upper end of 10 is placed so that the upper surface of the upper wall 10a and the upper surface 9b of the upper case 1a are substantially the same, so that the upper end of the closed front lid 10 and the upper case are closed. There is no gap between the front end of 1a and the entrance of dust. Further, the front end surface 9c of the upper wall 9 of the upper case 1a is inclined to be in contact with the inner surface upper portion 10b formed on the inclined surface of the front lid 10.

Therefore, since the front end surface 9c of the upper wall 9 is formed as an inclined surface as described above, the tape height regulating rib 14 is located inside the case from the tangent line T at the front portion of the peripheral surface of the boss 8 as shown in FIG. The front end face by setting the position slightly deviated by a
By escaping from 9c, a flat surface perpendicular to the front end surface 14a of the rib 14 is sufficiently secured. Thus, the tunnel gate G is set on the flat front end face 14a of the tape height regulating rib 14.

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

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

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 deviated inward from the tangent line T of the front portion of the peripheral surface of the boss 8 to the upper case 1a. Even when the front end surface 9c of the wall 9 is formed as an inclined surface, the front end surface 14a of the rib 14 has a sufficient width for attaching the tunnel gate G. Therefore, when the gate G is automatically cut, only the gate G is cut cleanly from the front end surface 14a without scraping off the gate portion on the front end surface 14a of the tape height regulating rib 14 or leaving a fragment, and the reliability is improved. You will get a high gate.

By providing a chamfer 15 for burr escape at the corner where the front end face 14a and the lower end face 14b of the tape height regulating rib 14 intersect, a highly reliable tape height regulating rib that does not damage the tape 4
You will get 14. Also, by forming the lower end surface 14b of the tape height regulating rib 14 into a rounded shape as shown in FIG. 5, it is possible to prevent the tape from being damaged by burrs.

[Another embodiment]

As shown in FIG. 6, when the front end surface 9c of the upper wall 9 is formed as a vertical surface, the front end surface 14a of the tape height regulating rib 14 is aligned with the tangent line T of the front portion of the peripheral surface of the boss 8. Formed by
The front end face 14a can be formed into a vertical flat with a sufficient width of the game.

[Brief description of drawings]

1 to 4 show an embodiment of a tape cartridge according to the present invention. FIG. 1 is an internal plan view of an upper case, FIG. 2 is a partial front view of the upper case, and FIG. FIG. 4 is a partial sectional view of the molding die of the upper case, and FIG. FIG. 5 is a sectional view of a tape pull-out 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 a tape cartridge according to another embodiment of 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 an upper case, and FIG. 9 is a perspective view of a main body case and a shutter. FIG. 10 is an enlarged sectional view taken along the line AA in FIG. 1 …… Main body case, 1a …… Upper case, 1b …… Lower case, 4 …… Tape, 5 …… Hub, 6 …… Tape outlet, 9 …… Upper wall, 10 …… Front lid, 14 …… Tape height regulation rib, 16 …… fixed mold, 17 …… movable mold, G …… tunnel gate.

Claims (1)

[Claims] 1. A hub 5 around which a tape 4 is wound is built in a main body case 1 formed by abutting upper and lower cases 1a and 1b, and tape outlets 6 and 6 are provided on the left and right of the front side of the main body case 1, and In a tape cartridge in which the tape 4 is pulled out from the outlet 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 portion inside the tape outlet 6 in the upper case 1a. A tape cartridge characterized in that a tunnel gate G is set on the front side of the regulation rib 14.