A method of forming a fused bifocal contact lens having "no jump" characteristics at all points of the segment line separating the distant vision segment or zone from the near vision zone is disclosed. In one embodiment a cylindrical blank is rotated about a given center line and a front curve imparted thereto by moving a tool in an arc about a point radially offset from said center line, in which an opening is then cut in the center of the resulting blank of a size desired to provide a distant ...

A mold assembly for injection molding of precision composite articles, which is particularly adapted for use in making highly precise oil seals having a rubber body bonded to a metal mounting flange. The assembly comprises a bottom mold member adapted to be supported in fixed relation to a vertically reciprocable top mold member, the bottom member has means forming an upwardly opening annular recess for supporting therein a circular oil seal stamping of generally L-shaped cross section with an i...

An apparatus for manufacturing fluid seals, which includes first and second mold parts movable along a given axis between open and closed positions. One mold part has a radially extending mold surface adapted to receive and support one surface of the flange portion of an insert to which a molded part of the seal is to be bonded, and the other mold part has a portion adapted to engage an opposite surface of the flange to hold the flange against the receiving and supporting mold surface to prevent...

A press and vacuum box combination for manufacturing articles from fluent, curable or hardenable material within a vacuum atmosphere, especially designed to provide access to the mold parts, optimum article handling and improved safety. The press has side frame members, a cross head lying in a horizontal plane and extending between the side frame members, an axially reciprocable ram movable between raised and lowered positions, a platen associated with the cross head and a platen associated with...

An apparatus and method for molding an article such as finished seal of known type, comprising a flexible member bonded to a rigid element. During conventional manufacture, the rigid element is clamped between upper and lower seal-forming molding elements and, in many instances, after engagement of the rigid element, continued traveling of the upper and lower molding elements toward each other is used to provide a "closed stroke". In the closed stroke operation of the present invention, the cont...

A disposable filter unit for use with a parts washer or the like. The filter consists of a body in the general form of a bag, made from a softenable but substantially solvent-impermeable thermoplastic material having a neck portion attached to a mounting collar. The mounting collar is a stiff but resilient element suitable for being positioned and retained within the drain opening of the parts washer, being constantly held in place by a cup or screen. The filter body has large by-pass openings i...

A combination flight vehicle and launching apparatus for use as a toy or as a teaching and demonstration aid. The launcher unit includes a base portion and a tower portion, with the tower having an elastic member affixed thereto at one end and a portion of a latch assembly disposed on the other end. The latch portion is adapted to cooperate with part of the flight vehicle to hold it in position prior to launching. The free end of the elastic member or energizer is releasably attached to the nose...

An apparatus for molding articles, particularly those having a body portion formed from a cured material and bonded to a relatively rigid insert portion. Two mold members are arranged for relative movement along a given axis between open and closed positions. Each of the members includes surfaces at least partly directed towards each other to define in said closed position of the members, a molding cavity between the members. One of the mold members has a part for engaging a relatively rigid ins...

Various oil seal constructions are described in which the flexible primary lip portion is defined by converging first and second, at least partially axially undulating, frusto-conical surfaces disposed respectively at first and second included angles with respect to the axis of said seal unit, facing respectively the exterior and interior of a region to be sealed, with the lip engaging an oppositely directed surface portion of a sealed element in fluid-tight relation along an undulating seal ban...

An oil seal and novel rubber composition especially adapted for use as an oil seal material and thus requiring highly specialized physical properties. The rubber comprises a major portion of a polyacrylate elastomer having therein up to about 25% of a modifier imparting outstanding low temperature performance to rubber compositions which are otherwise unsuited for use in very low temperature environments. A preferred seal is made from a rubber composition which includes, based on 100 parts of ru...