Patent ID: 7682098

Claim:
A liquid applicator having a collapsible liquid reservoir comprising: a. an elongated outer chamber wall and a seal preventing leakage in the liquid reservoir and having a characteristic length; b. an inner piston having a length substantially equal to the characteristic length, wherein the inner piston is telescopically received in the outer chamber wall; c. an elongated intermediate chamber wall having a length substantially equal to the characteristic length and wherein the intermediate chamber wall is telescopically received in the outer chamber wall and located circumferentially intermediate the inner piston and the outer chamber wall, the intermediate chamber wall including an end cap having a first portion disposed circumferentially around the intermediate chamber wall and a second portion extending partially over an end of the intermediate chamber wall and defining an opening providing fluid communication between the liquid reservoirs formed by the intermediate and outer chamber walls, and including a seal preventing leakage in the liquid reservoir formed by the intermediate chamber wall, and wherein the intermediate chamber wall and the inner piston are each telescopically movable relative to one another and to the outer chamber wall, and may be telescopically expanded to i. a fully expanded condition wherein the outer chamber wall and the inner chamber wall form the liquid reservoir, and the combined length of the liquid reservoir and inner piston is about three times the characteristic length, and ii. a partially expanded condition wherein the combined length of the liquid reservoir and inner piston is substantially less than half the length of the liquid reservoir and piston in the fully expanded condition; and d. a liquid applicator head in fluid communication with the collapsible liquid reservoir.