Abstract: A modular barrier system enables demountable outdoor rinks—typically for ice hockey, or ice skating, or street hockey. A rink includes multiple panels, each having a factory-attached link. These panels are linearly disposed, adjacent to one another, to form a piecewise continuous boundary wall enclosing a desired area. Attaching one link to the next, typically via insertion of a thumbscrew, connects the panels into a robust assembly. Both straight and curved panels are provided, thereby enabling a rink with round corners. Each panel includes a shell molded from plastic resin, and has a hollow interior which can be filled with water (or other ballast).

Abstract: A high performance, yet low cost, modular barrier system enables demountable outdoor rinks—typically for ice hockey, or ice skating, or street hockey—that are robust and convenient to install. A rink includes multiple panels, each having a factory-attached link. These panels are linearly disposed, adjacent to one another, to form a piecewise continuous boundary wall enclosing a desired area. Attaching one link to the next, typically via insertion of a thumbscrew, connects the panels into a robust assembly. Both straight and curved panels are provided, thereby enabling a rink with round corners. Each panel includes a shell molded from plastic resin, and has a hollow interior which can be filled with water (or other ballast).

Abstract: A portable ice rink includes a wall formed of multiple wall members linearly disposed adjacent to one another to form a piecewise continuous wall that encloses a desired area, and also includes a chain of links disposed on the outside of the wall members for reinforcement. The rink may further include a waterproof tarp extending underneath the wall members and folded upwards along the outer side of the wall, with its edge tied to the change of links. The tarp can contain water which then freezes to form a skating surface. Curved wall members are provided to form a rink with round corners. Each wall member is a discrete unit, made of molded plastic, and having a hollow interior which can be filled with water (or other ballast). Each wall member is designed with stiffening features to maintain the flatness of its inner surface after filling.

Abstract: A portable ice rink includes a wall formed of multiple wall members linearly disposed adjacent to one another to form a piecewise continuous wall that encloses a desired area, and also includes a chain of links disposed on the outside of the wall members for reinforcement. The rink may further include a waterproof tarp extending underneath the wall members and folded upwards along the outer side of the wall, with its edge tied to the change of links. The tarp can contain water which then freezes to form a skating surface. Curved wall members are provided to form a rink with round corners. Each wall member is a discrete unit, made of molded plastic, and having a hollow interior which can be filled with water (or other ballast). Each wall member is designed with stiffening features to maintain the flatness of its inner surface after filling.

Abstract: An actuating mechanism for spectacles which include two variable focal length lens units. Each lens unit is fitted with a coupling member which extends from the lens unit into the bridge of the spectacles. A linearly-movable finger-operated slider, having a finger pad extending above the bridge, causes a cam within the bridge to rotate as it is moved, the cam being coupled to the coupling members causing them to move and the focal length of the lens units thereby to change.

Abstract: A liquid-filled variable focal length lens of the type which has a distensible membrane as one of the lens surfaces, and a membrane support member to support the perimeter of the free area of the membrane. By using a membrane support member having a toroidally shaped portion, the membrane is supported such that it has a circular free area irrespective of the shape of the perimeter of the lens. The cross sectional shape of the toroidal portion of the support member is preferably approximately an arc of a circle, and the perimeter of the free area of the membrane is maintained tangent thereto.