Claims
- 1. In a disk cartridge with a case comprising an upper and a lower shell halves for accommodating a disk and a spindle insertion hole located at a center of the cartridge and a head insertion hole adjacent the spindle insertion hole on each shell half so that the head insertion hole and the spindle insertion hole are opened and closed by a closing plate of a shutter, the improvement in which each shell half is formed by an injection molding of polycarbonate in which a mold having a single injection hole is used, the injection hole being opened directly to a cavity corresponding to a groove formed adjacent the spindle insertion hole in the case in a lateral direction of the case for receiving a retaining plate to guide a slide plate formed at a distal portion of the closing plate of the shutter, a distal opening end of the injection hole being opposed directly to a center of the cavity corresponding to the groove for receiving the retaining plate in the lateral direction of the case, so that polycarbonate is supplied perpendicularly to an extending direction of the groove for the retaining plate.
- 2. A disk cartridge according to claim 1, wherein the injection hole has a diameter of about 1.5 mm in the case of a 5-inch disk cartridge.
- 3. A disk cartridge according to claim 1, wherein said mold is used under condition of a mold temperature of 80.degree. to 90.degree. C., an injection pressure of 1,500 to 1,600 kg/cm.sup.2, and a melted resin temperature of 250.degree. to 280.degree. C.
- 4. In a mold for injection molding of a disk cartridge with a case made of polycarbonate and comprising an upper and a lower shell halves for accommodating a disk and a spindle insertion hole located at a center of the cartridge and a head insertion hole adjacent the spindle insertion hole on each shell half so that both holes the head insertion hole and the spindle insertion hole are opened and closed by a closing plate of a shutter, the improvement in which said mold comprises two half molds to be assembled with each other to form a casing cavity for either the upper or lower shell half of the case, either of two half molds having a single injection hole which is opened directly to a cavity corresponding to a groove formed adjacent the spindle insertion hole in the case in a lateral direction of the case for receiving a retaining plate to guide a slide plate formed at a distal portion of the closing plate of the shutter, a distal opening end of the injection hole being opposed directly to a center of the cavity corresponding to the groove for receiving the retaining plate in the lateral direction of the case, so that polycarbonate is supplied perpendicular to an extending direction of the groove for the retaining plate.
- 5. A mold according to claim 4, wherein the injection hole has a diameter of about 1.5 mm in the case of a 5-inch disk cartridge.
- 6. A mold according to claim 4, wherein said mold is used under condition of a mold temperature of 80.degree. to 90.degree. C., an injection pressure of 1,500 to 1,600 kg/cm.sup.2, and a melted resin temperature of 250.degree. to 280.degree. C.
Priority Claims (11)
Number |
Date |
Country |
Kind |
2-007307 U |
Jan 1990 |
JPX |
|
2-007308 U |
Jan 1990 |
JPX |
|
2-007704 U |
Jan 1990 |
JPX |
|
2-007705 U |
Jan 1990 |
JPX |
|
2-018572 U |
Feb 1990 |
JPX |
|
2-018573 U |
Feb 1990 |
JPX |
|
2-018574 U |
Feb 1990 |
JPX |
|
2-026505 U |
Mar 1990 |
JPX |
|
2-064869 |
Mar 1990 |
JPX |
|
2-013182 U |
Apr 1990 |
JPX |
|
2-100585 U |
Sep 1990 |
JPX |
|
Parent Case Info
This is a continuation of application Ser. No. 08/398,051 filed Mar. 2, 1995 now abandoned which is a Continuation of U.S. Ser. No. 08/245,857 filed May 19, 1994, now abandoned, which is a Continuation of U.S. Ser. No. 07/931,587 filed Aug. 18, 1992, which is a Division U.S. Ser. No. 07/647,571 filed Jan. 28, 1991 now U.S. Pat. No. 5,166,922 now abandoned.
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Date |
Kind |
4714973 |
Kato et al. |
Dec 1987 |
|
4827468 |
Odawara et al. |
May 1989 |
|
4866697 |
Yamaguchi et al. |
Sep 1989 |
|
4945530 |
Sandell et al. |
Jul 1990 |
|
5161081 |
Machida et al. |
Nov 1992 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
647571 |
Jan 1991 |
|
Continuations (3)
|
Number |
Date |
Country |
Parent |
398051 |
Mar 1995 |
|
Parent |
245857 |
May 1994 |
|
Parent |
931587 |
Aug 1992 |
|