Patent ID: 8079557

Claim:
A suction cup device comprising: a cup forming unit adapted to confront a flat surface, and defining a central axis normal to the flat surface to cooperate therewith to create a volume-variable space, said cup forming unit having a central portion which has suction-side and pull-side central surfaces opposite to each other in a direction of the central axis, and which is made from an elastic material such that, when said central portion is subjected to a pulling force along the central axis away from the flat surface, said suction-side surface is deformed to produce a reduced pressure in said volume-variable space while acquiring a biasing force to urge said central portion toward the flat surface, and a peripheral portion which extends from said central portion to terminate at a marginal end, said marginal end being configured to be in fluid-tight engagement with the flat surface; a liftable rod having a base end secured to said central portion, and a rod segment extending from said base end along the central axis and having an externally threaded region; a bracing shell member including a mount wall which is spaced apart from said central portion in the direction of the central axis, and which has a central hole that permits passage of said rod segment therethrough, and a circumferential abutment region that is disposed outwardly and radially of said central hole, said mount wall having a surrounding marginal cutout portion which extends towards said peripheral portion to terminate at said circumferential abutment region, and a force-transmitting surrounding wall which extends in the direction of central axis from said circumferential abutment region, and which is in engagement with said peripheral portion; and a twistable cap member having a surrounding bottom wall which abuts against said circumferential abutment region, and which is in form of an abutting rim that is configured to be fit in said marginal cutout portion, and an inner tubular surface which surrounds the central axis and which has an internally threaded region threadedly engaged with said externally threaded region such that, as a result of a manually twisted movement of said twistable cap member, said rod segment is axially moved relative to said inner tubular surface, thereby imparting said base end with the pulling force, and such that, once the manually twisted movement of said twistable cap member is discontinued for reaching a predetermined value of the reduced pressure, said surrounding bottom wall is urged by the biasing force to abut against said circumferential abutment region, thereby ensuring the fluid-tight engagement of said marginal end with the flat surface.