Invalidity dossier
US 1557270
Vacuum cup for washing machines
Current assignee: Individual
Added 9/23/2026, 6:56:49 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 1557270 A
Title: Vacuum cup for washing machines
Inventor: William E. Pinckney, of Portland, Multnomah County, Oregon, a US citizen
Assignee (per source): Individual (original assignee: Individual)
Application No.: US 748,920
Filing / Priority Date: November 10, 1924
Publication (Grant) Date: October 13, 1925
Anticipated Expiration: October 13, 1942; legal status listed as "Expired – Lifetime"
Classification: D06F 15/00 — washing machines having beating, rubbing or squeezing means in receptacles stationary for washing purposes
Source: https://patents.google.com/patent/US1557270/en
Purpose (from the specification): To provide an exceedingly simple and efficient type of pounder usable in square or rectangular containers without ratcheting devices or means for shifting the position of the clothes; to construct the cups so that practically every portion of the container is within reach of their pounding action; and to adapt the pounder for use with the washing machine described in the inventor's companion application, Serial No. 748,921.
Plain-language scope: The device sits in the lower part of a rectangular water container (bottom 10, sides 11 and 12). A tubular guide 13 on the bottom slidably mounts a plunger 14. Crossed arms 16 and 17 are secured across the plunger's upper end 15, carrying T-shaped cups 18 and longitudinal cups 19 fastened by short rods 20. In use, clothes and water go in and the plunger is reciprocated by an actuating device (not shown). The cup shapes leave sufficient area between cups for water and clothes displacement and suds formation, eliminating special mechanisms to bring all clothes under the pounders.
Claim 1 (sole claim): The combination of a rectangular water container having a vertical plunger mounted near the middle of its bottom; a pair of crossed arms attached to the upper end of said plunger; a pair of T-shaped cups at the opposite ends of one pair of arms; and a pair of longitudinal cups on the opposite ends of the remaining pair of arms, said longitudinal cups occupying space between said T-shaped cups, all of said cups occupying the major portion of the area of said water container.
What this excerpt does not establish: The companion application Serial No. 748,921 is identified but its text is not supplied. The actuating device, materials, cup dimensions, and drawings' full content are not described beyond the cited figures. The excerpt provides no information on assignments, litigation, validity, or prior art beyond a list of "similar documents." Legal status is stated by the source as an assumption, not a legal conclusion.
Generated 10/1/2026, 9:42:25 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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