Flexible sealing strip extendible around an enclosed movable member of predetermined contour

Claim 1

The combination with a mastic applying tool including: a. a mastic holding housing having parallel sidewalls; B. a bottom wall interconnecting the sidewalls and having an outlet opening therein for the mastic; c. a rectangular pressure plate having one end fulcrummed in the housing and having its other end movable along an arcuate wall of said housing as the pressure plate is swung toward the bottom wall for forcing mastic through the outlet opening, said plate having a groove in three of its edges for receiving a sealing strip; of d. a flexible sealing strip having an inner edge receivable in said pressure plate groove, the inner edge having V-shaped recesses positioned so as to register with the groove corners formed at the junctures of the three grooves of said plate for permitting said strip to be bent at the groove corners, the edges of the recesses being brought into abutting relation; e. the outer edge of said strip being free of any recesses and slidably contacting with the sidewalls and arcuate wall of said housing, said outer edge being formed into angular portions at the plate corners, these angular portions constituting sliding seals between said plate corners and the adjacent corners formed by the sidewalls and arcuate wall of said housing.