Abstract: A heating, ventilation, and air conditioning (HVAC) system includes a primary heat transfer circuit having a first heat exchanger fluidly coupled to an ambient environment and a compressor fluidly coupled to the first heat exchanger and configured to circulate a refrigerant through the primary heat transfer circuit. The HVAC system also includes a secondary heat transfer circuit having a second heat exchanger fluidly coupled to a thermal load and a pump fluidly coupled to the second heat exchanger and configured to circulate a heat transfer fluid through the secondary heat transfer circuit, where the heat transfer fluid is a non-volatile or inert fluid.

Abstract: A rope climbing apparatus (15) comprising a frame (16), a seat (18) supported by the frame and adapted to move relative to the frame from a first position (19) to an elevated second position (20), a lower pulley assembly (21) connected to the seat, an upper pulley assembly (22) connected to the frame, a rope (23) extending between the lower pulley assembly and the upper pulley assembly and having a rope climbing portion (24) graspable by a user (25) when the user is seated on the seat, and the rope, the seat, the lower pulley assembly and the upper pulley assembly configured and arranged such that a downward force (26) on the rope climbing portion of the rope causes an upward force (28) on the seat. The downward force on the rope climbing portion may result in an upward force on the seat at a mechanical advantage provided by the lower pulley assembly and the upper pulley assembly, and the mechanical advantage may be four.

Abstract: A rope climbing apparatus (15) comprising a frame (16), a seat (18) supported by the frame and adapted to move relative to the frame from a first position (19) to an elevated second position (20), a lower pulley assembly (21) connected to the seat, an upper pulley assembly (22) connected to the frame, a rope (23) extending between the lower pulley assembly and the upper pulley assembly and having a rope climbing portion (24) graspable by a user (25) when the user is seated on the seat, and the rope, the seat, the lower pulley assembly and the upper pulley assembly configured and arranged such that a downward force (26) on the rope climbing portion of the rope causes an upward force (28) on the seat. The downward force on the rope climbing portion may result in an upward force on the seat at a mechanical advantage provided by the lower pulley assembly and the upper pulley assembly, and the mechanical advantage may be four.

Abstract: A size-adjustable, foldable hamstring stretching apparatus of unitary construction provides for easily, effectively, and efficiently exercising (stretching) the hamstrings. The apparatus consists of a unitary frame and is used in a prone position, thus, avoiding back strain. The apparatus provides means for supporting the user's foot and means for assuring that the user's leg is maintained in a straight position. Means for holding allows for ease in grasping the apparatus allowing the user to pull or push the apparatus as desired. The means for supporting a foot, maintaining the leg in a straight position, and for holding may all be padded or made of a soft material for increased ease of use and comfort. The frame is made of any strong, lightweight material, such as plastic or aluminum and it is contemplated that the apparatus be made using a molding process to reduce the cost of manufacturing.

Abstract: A ladder-climbing exercise device (10) includes an inclined flight (13) along which a plurality of rungs (29) are presented in an endless manner. The marginal ends of the rungs are mounted on endless chains which are supported by a frame. The chains are coupled to a fan (43) having a squirrel cage-like rotor. The position of an operator (P) relative to the flight changes the size of a fan aperture (45) to vary the resistance afforded by the device to the climbing motion.