Claims
- 1. A perforator for forming perforations at regular intervals in first sections of a continuous photographic film, said first sections alternating with second sections of a constant length along said continuous photographic film, said second sections having no perforations formed therein, said perforator comprising:
- a die set having a plural number of punches and dies arranged in a feeding direction of said continuous photographic film;
- an actuating device for actuating said die set to perform die-punching to form said plural number of said perforations at once through a length of A in said continuous photographic film;
- a film feeder for intermittently feeding said continuous photographic film; and
- a main controller for controlling said film feeder and said actuating device such that when said first section has a length of N.times.A, N being an integer, and said constant length of said second section is B-A, said film feeder feeds said continuous photographic film intermittently (N-1) times by the length A and, thereafter, once by a length of B, and such that said die set is actuated by said actuating device after each film feeding.
- 2. A perforator according to claim 1, wherein said main controller is configured to control said film feeder to feed said continuous photographic film at a higher speed for the B length feeding than for the A length feeding to maintain a feeding time for each film feeding constant, and maintain a die-punching interval of said die set constant.
- 3. A perforator according to claim 1, wherein said main controller is configured to control said film feeder to feed said continuous photographic film at the same speed for the A length feeding and the B length feeding.
- 4. A perforator according to claim 1, further comprising at least a pilot pin and a die for said pilot pin which are disposed in a downstream portion of said die set in said feeding direction, and a driving device for driving said pilot pin to be inserted in said die such that a leading one of said perforations to be formed by die-punching of the die set subsequent one of said A length feedings is spaced from a trailing one of said perforations formed by the preceding die-punching of the die set in said feeding direction at said regular interval, and said pilot pin not being inserted in said die during the die-punching of said die set following the B length feeding.
Priority Claims (2)
Number |
Date |
Country |
Kind |
4-326981 |
Dec 1992 |
JPX |
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4-329506 |
Dec 1992 |
JPX |
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Parent Case Info
This is a divisional of application Ser. Nos. 08/704,977 filed Aug. 28, 1996, now U.S. Pat. No. 5,746,001, which is a divisional of application Ser. No. 08/162,299, filed Dec. 7, 1993, now abandoned.
US Referenced Citations (15)
Foreign Referenced Citations (6)
Number |
Date |
Country |
0329172 |
Aug 1989 |
EPX |
1530062 |
May 1968 |
FRX |
4135787 |
May 1992 |
DEX |
61-214999 |
Sep 1986 |
JPX |
42800 |
Jan 1992 |
JPX |
496056 |
Mar 1992 |
JPX |
Divisions (2)
|
Number |
Date |
Country |
Parent |
704977 |
Aug 1996 |
|
Parent |
162299 |
Dec 1993 |
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