US3903540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Daylight developing tank
Assignee: Meopta np
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Filing: 1974-05-03
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Granted: 1975-09-02
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Expires: 1994-05-03
Abstract
Abstract A parallelepiped daylight developing tank for developing one or more pieces of flat photographic material, such as plates or sheets of paper. The tank is formed by a body having side walls in which guideway means is provided to bear a slidable, lightproof cover provided with at least one pour-in opening and a system for stirring the solution during the developing process. The developing area of the tank is separated from its rear wall and front wall by partitions defining a system of labyrinth channels communicating with the developing area, into which the pour-in openings, provided in the cover, lead.
Inventors
- 👤 Jan Hampl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:05
CPC Classifications
G; G03; G03D; G03D13/00; G03D13/02; G03D13/04; G03D13/06
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
157 words
A photographic developing tank comprising a parallelepiped body having side and end walls, a pair of interior partitions extending between said side walls spaced from each other to define a developing area within said body and spaced respectively from each of the end walls to define labyrinth channels at each end of said body communicating with said developing area, a removable cover for said body, having openings aligned with said labyrinth channels for introduction and removal of fluid, said cover and said body having cooperating means for maintaining said developing area light-free, and a system for stirring, comprising an elongated, flexible plate secured at one end to the lower surface of said cover and having its other end extending over said developing area, an actuating button in contact with said plate, said acuating button passing through a hole in said cover, said hole being surrounded by an annular flange forming a disk shaped recess for said button.
Claim 2
Dependent Claim
157 words
A photographic developing tank comprising a parallelepiped body having side and end walls, a pair of interior partitions extending between said side walls spaced from each other to define a developing area within said body and spaced respectively from each of the end walls to define labyrinth channels at each end of said body communicating with said developing area, a removable cover for said body, having openings aligned with said labyrinth channels for introduction and removal of fluid, said cover and said body having cooperating means for maintaining said developing area light-free, and a system for stirring, comprising an elongated, flexible plate secured at one end to the lower surface of said cover and having its other end extending over said developing area, an actuating button in contact with said plate, said acuating button passing through a hole in said cover, said hole being surrounded by an annular flange forming a disk shaped recess for said button.
Claim 3
Dependent Claim
25 words
The developing tank according to claim 1 wherein the lower surface of said cover is formed with a recess for normally receiving said flexible plate.
Claim 4
Dependent Claim
28 words
The developing tank according to claim 1 wherein said button is attached to said plate, and including spring means for normally biasing said button outwardly of said plate.
Claim 5
Dependent Claim
29 words
The developing tank according to claim 3 including a pin connecting said button on said plate and a helical spring surrounding said button between said cover and said button.
Claim 6
Dependent Claim
38 words
The developing tank according to claim 1 including spacers loosely inserted within said developing area for supporting photographic sheets to be developed, said spacers comprising a plastic mesh body adapted to permit circulation of fluid within said area.
Claim 7
Dependent Claim
28 words
The developing tank according to claim 1 including means mounted on said partitions and extending into said developing area for grasping photographic sheets located in said developing area.
Claim 8
Dependent Claim
33 words
The developing tank according to claim 1 wherein said grasping means comprise at least one resilient claw mounted on the upper edge of said partion and extending toward the bottom of said body.
Claim 9
Dependent Claim
154 words
A photographic developing tank comprising a parallelepiped body having side and end walls, interior partitions extending between said side walls spaced from each other to define a developing area within said body and spaced respectively from each of the end walls to define labyrinth channels at each end of said body communicating with said developing area, and a cover for enclosing said body having openings aligned with said labyrinth channels for the introduction and removal of fluid, said cover having side walls adapted to depend adjacent the sidewalls of said body, and to be slidable over said body from one end to the other, said side walls of said body and cover having cooperating means for slidably engaging said body in closed condition, the lower surface of said cover having means engaging the upper edges of said side and end walls and said partitions to seal said body against passage of fluid and light.
Claim 10
Dependent Claim
154 words
A photographic developing tank comprising a parallelepiped body having side and end walls, interior partitions extending between said side walls spaced from each other to define a developing area within said body and spaced respectively from each of the end walls to define labyrinth channels at each end of said body communicating with said developing area, and a cover for enclosing said body having openings aligned with said labyrinth channels for the introduction and removal of fluid, said cover having side walls adapted to depend adjacent the sidewalls of said body, and to be slidable over said body from one end to the other, said side walls of said body and cover having cooperating means for slidably engaging said body in closed condition, the lower surface of said cover having means engaging the upper edges of said side and end walls and said partitions to seal said body against passage of fluid and light.
Claim 11
Dependent Claim
40 words
The developing tank according to claim 8 wherein the upper edge of the side and end walls of said body and said partition vary in height from one end to the other, and said cover varies in thickness corresponding thereto.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |