Abstract: An improved roll-up closure utilizing a flexible cover or curtain selected from a material suitable to effect the type of closure sought. The cover is at least as wide as the portal to be covered and is typically longer than the portal. Each lateral margin of the cover has a strip of hook and loop fastener material affixed thereto, and a complementary strip is affixed to the lateral margins of the structure defining the portal. A first end of the cover is rigidly affixed across a first margin of the portal. The opposite end of the cover can be upturned and connected to a driven take-up roller mounted to the first margin of the portal. In this embodiment, an elongated transverse rod is supported within the upturned end of the cover. In an alternate embodiment, the opposite end of the cover is attached to an elongated transverse rod such that as the curtain is raised or lowered, the curtain is wound or unwound around the rod, respectively.

Abstract: An improved roll-up closure utilizing a flexible cover or curtain selected from a material suitable to effect the type of closure sought. The cover is at least as wide as the portal to be covered and is typically longer than the portal. Each lateral margin of the cover has a strip of hook and loop fastener material affixed thereto, and a complementary strip is affixed to the lateral margins of the structure defining the portal. A first end of the cover is rigidly affixed across a first margin of the portal. The opposite end of the cover is upturned and connected to a driven take-up roller mounted to the first margin of the portal. An elongated transverse rod is supported within the upturned end of the cover. Activation of the driven roller lengthens or shortens the effective length of the cover and moves the rod therewith. As the driven roller is activated, the mating hook and loop fasteners are positioned to seal and unseal the cover to the lateral margins of the portal.

Abstract: A device for actuating switches in a power winch apparatus used in livestock enclosures. An actuator block is mounted on a linear rod within the frame of the power winch. When the winch is operated the movable load bearing block of the power winch engages and moves manually adjustable limits on the rod. Subsequently the actuator block mounted to the rod moves relative to a series of switches which are electrically connected to auxiliary devices as well as the power supply and drive motor of the power winch.

Abstract: A method for ventilating an animal enclosure using a plurality of closable ventilation openings. Sensors measure ambient outside temperature and ambient atmospheric pressure. A controller correlates said measurements for temperature, and pressure to determine a differential pressure between the interior of said enclosure and atmospheric pressure. Air is then transported by said fans to draw said air in a predetermined volume to achieve said determined differential pressure.

Abstract: A unitized metallic fan housing having a peripheral wall spaced about a fan's axis of rotation and extending axially therebeyond. A plurality of flanges are integrally connected to and extend substantially perpendicular to the peripheral wall toward the axis of rotation. At least one screen is connected to the flanges by rigid but malleable tabs formed thereon that are bent around a peripheral strand of the screen. Apertures are defined by and extend through the flanges to provide access to the tabs such that the tabs may be urged toward the peripheral wall to tension the screen therewithin, whereby the rigid nature of the tabs secures the screen to the flanges in a tensioned position. Holes are defined by and extend through the peripheral wall to provide access to the tabs such that the tabs may be urged from the peripheral wall to reduce the tension of the screen and to disengage the peripheral strand from the tabs such that the screen may be removed from the peripheral wall and replaced.

Abstract: Sensor circuitry which detects the presence or absence of material and activates a motor responsive thereto, having a capacitor which emits electric signal responsive to the presence of the material, a signal processing unit receives the capacitor's signal and shapes it into a usable signal, wherein the usable signal is received by a timer which is held in reset thereby. When the material's presence is no longer detected, the timer counts a delay during which a control signal is output to a control transistor which responsively actuates a relay which is connected to and forms a link of a power circuit that supplies energy to the motor. A transformer is connected to the power circuit and selected windings of the transformer are connected to the relay. When the transistor is off and relay is inactive, there is a large voltage drop across the transformer thereby deactivating the motor.