US3792845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver recovery unit
Assignee: Individual
•
Filing: 1972-12-11
•
Granted: 1974-02-19
•
Expires: 1992-12-11
Abstract
Abstract An improved unit for the recovery of silver from spent photograhic processing solutions by a metallic replacement technique. The unit is designed to pass silver-bearing photographic processing solution through a roll of steel wool, and includes a high-density polyethylene cartridge to hold the steel wool, fitted with suitable plumbing for passing the solution through the roll in the cartridge. The polyethylene cartridge is essentially a drum with a generally flat lid, and includes a rim clamp for locking the lid tightly on the drum. The rim clamp fits around the top of the drum and has a lever lock operable from one side of the drum. The plumbing attached to a drum includes fittings for routing the solution into and out of the drum through a pair of openings in the cartridge lid. When the unit is in operation, feed solution passes into the top of the cartridge, contacts the steel wool roll in the cartridge drum, and then passes out of the drum for recycle use or discard to a sewer. The unit operates efficiently until the steel wool in the cartridge is exhausted, at which point it becomes necessary to replace the cartridge. This requires removal of the cartridge lid, but the removal can be easily accomplished without disconnecting the plumbing from the lid since the lever lock is operable from the side of the drum to permit loosening of the clamp for easy movement of the lid with the plumbing attached.
Inventors
- 👤 H Ott
- 👤 K Larson
- 👤 J Drew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:34
CPC Classifications
C; C22; C22B; C22B11/00; C22B11/04; C22B11/042; C22B11/046; C22B3/00; C22B3/02; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
193 words
Cartridge means particularly suitable for use in the recovery of silver from spent photographic processing solutions comprising, in combination: a drum with an outturned flange around its top; a lid for said drum having a peripheral lip adapted to fit over said outturned flange, said lid being further characterized by the presence of a pair of outthurst bosses defining openings therethrough, the outthrust bosses being adapted to receive plumbing means for admitting feed solution to said drum for desilvering treatment therein and draining the solution from the drum after it has been desilvered; and a rim clamp adapted to encircle and radially embrace the edges of the outturned flange of the drum and the overlying peripheral lip of said lid, when the lid is positioned on said drum, said rim clamp being of an expansible and contractible type whereby it can be tightened and locked to fasten the lid in place on the drum, and having a locking mechanism operable at the outer periphery of the clamp to permit the latter to be loosened, for removal of the lid from the drum, without the necessity of separating said plumbing means from said lid.
Claim 2
Dependent Claim
193 words
Cartridge means particularly suitable for use in the recovery of silver from spent photographic processing solutions comprising, in combination: a drum with an outturned flange around its top; a lid for said drum having a peripheral lip adapted to fit over said outturned flange, said lid being further characterized by the presence of a pair of outthurst bosses defining openings therethrough, the outthrust bosses being adapted to receive plumbing means for admitting feed solution to said drum for desilvering treatment therein and draining the solution from the drum after it has been desilvered; and a rim clamp adapted to encircle and radially embrace the edges of the outturned flange of the drum and the overlying peripheral lip of said lid, when the lid is positioned on said drum, said rim clamp being of an expansible and contractible type whereby it can be tightened and locked to fasten the lid in place on the drum, and having a locking mechanism operable at the outer periphery of the clamp to permit the latter to be loosened, for removal of the lid from the drum, without the necessity of separating said plumbing means from said lid.
Claim 3
Dependent Claim
129 words
Cartridge means in accordance with claim 1 in which the desilvering treatment comprises subjecting the feed solution to intimate contact with steel wool wound in the form of a roll around a hollow core and snugly positioned in said drum, and said cartridge means includes spacer means adapted to support the steel wool roll at a level above the bottom of the drum to provide space in the bottom of said drum for the accumulation of the below-mentioned sludge; whereby silver is precipitated from said solution as a result of metallic replacement action when the silver contacts said steel wool, and the precipitated silver gravitates to said space in the bottom of said drum as a component of a sludge which can be removed for recovery of said silver.
Claim 4
Dependent Claim
16 words
Cartridge means in accordance with claim 2 in which said locking mechanism is a lever lock.
Claim 5
Dependent Claim
30 words
Cartridge means in accordance with claim 3 in which said drum and lid are each made of a heavy duty plastic material substantially impervious to attack by said feed solution.
Claim 6
Dependent Claim
20 words
Cartridge means in accordance with claim 4 in which the drum and lid are of rotationally molded, high-density polyethylene construction.
Claim 7
Dependent Claim
57 words
Cartridge means in accordance with claim 5 including an O-ring gasket for said lid, said gasket being made of a rubbery material substantially impervious to attack by said feed solution and capable of providing a tight seal around the top of said drum when said lid is fastened in place thereon by means of said rim clamp.
Claim 8
Dependent Claim
16 words
Cartridge means in accordance with claim 6 in which said gasket is made of Buna-N rubber.
Claim 9
Dependent Claim
114 words
Cartridge means in accordance with claim 7 in which said pair of downthrust sockets defining openings in said lid includes a first socket situated at the center of the lid, said tubular core of said steel wool roll is pOsitioned directly underneath said first socket when said drum is loaded with said roll for operation of said cartridge means, and the bottom of said first socket is aligned with said tubular core and serves as a stop to prevent upward movement of the latter to thereby hold said steel wool roll at the proper level within said drum to provide space thereabove for the inflow of feed solution during operation of said cartridge means.
Claim 10
Dependent Claim
72 words
Cartridge means in accordance with claim 7 in which said pair of outthrust bosses defining openings in said lid comprise a pair of upthrust, externally threaded bosses of round cross section, including a first boss situated at the center of the lid and said tubular core of said steel wool roll is positioned directly underneath said first boss when said drum is loaded with said roll for operation of said cartridge means.
Claim 11
Dependent Claim
70 words
Cartridge means in accordance with claim 8 in combination with an outlet tube forming part of said plumbing means and adapted to extend downwardly from said first socket in said lid and fit snugly within said tubular core, when the lid is positioned on the drum, to receive desilvered solution which has passed through said steel wool to permit drainage thereof from said drum during operation of the cartridge means.
Claim 12
Dependent Claim
71 words
Cartridge means in accordance with claim 9 in combination with an outlet tube forming part of said plumbing means and adapted to extend downwardly from said first boss in said lid and fit snugly within said tubular core, when the lid is positioned on the drum, to receive desilvered solution which has passed through said steel wool roll to permit drainage thereof from said drum during operation of the cartridge means.
Claim 13
Dependent Claim
160 words
The cartridge means-outlet tube combination of claim 11 in which said plumbing means includes a circulating unit having a T-shaped inlet fitting with a first tubular vent adapted to route feed solution from a feed line into said drum when the cartridge means is in service, a T-shaped outlet fitting with a second tubular vent adapted to route desilvered solution from said outlet tube into a drain line from said drum when said cartridge means is in service, and a U-shaped by-pass tube with a vent opening in the top of its bight connecting the first and second tubular vents in the inlet and outlet fittings; the inlet and outlet fittings being adapted for threaded connection with said externally threaded bosses, said first boss being threaded internally from the bottom and said outlet tube being externally threaded at its upper end whereby said outlet tube is threadedly engageable with said first boss for downward extension therefrom within said tubular core.
Claim 14
Dependent Claim
13 words
The combination of claim 12 in further combination with said steel wool roll.
References Cited (Backward Citations)
US3630505A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-18 | 1977-08-20 | 1978-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-18 | 1981-08-20 | 1982-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-18 | 1985-08-20 | 1986-02-19 | $7700.00 | Window Closed / Lapsed |