Flexxaire Manufacturing Inc.

Argus Machine Co., Ltd.

Brian J Bruchal

Jonathan Edwards McCallum

Murray C Gerwing

Jason Weiss

William MacDonald

A pressure switch is disclosed, comprising: a spool forming a pressure sensitive end; an actuating rod extended into the spool and slidable over a limited range within the pressure switch under external fluid pressure on the pressure sensitive end; a switch housing containing a switch operatively connected to the actuating rod; and a cylindrical connector terminating in a first axial end and a second axial end, the cylindrical connector being threaded into the spool at the first axial end and into the switch housing at the second axial end. A pressure switch is also disclosed comprising: a housing defining an interior bore that terminates in a pressure sensitive end of the housing; an actuating rod slidable over a limited range within the interior bore under external fluid pressure on the pressure sensitive end; a switch, within the housing, operatively connected to the actuating rod; and outwardly extending fins mounted on the housing.

Pressure switch

An apparatus for sensing pressure is provided comprising a housing, electronics, a pressure sensor and a secondary seal. The housing comprises an interior bore and a first end, with the interior bore forming an opening at the first end. The electronics may be disposed in the interior bore. The pressure sensor is mounted at the first end of the interior bore. The pressure sensor may be operatively connected to send signals to the electronics in response to external fluid pressure. The pressure sensor may, at least in part, form a primary seal at the first end of the interior bore. The secondary seal may be disposed in the interior bore in between the pressure sensor and the electronics. The secondary seal may be configured to act as a backup seal to the primary seal. The secondary seal provides an added degree of safety from high pressure pipeline contents. The secondary seal also ensures that the important interior electrical components of the apparatus are not damaged upon failure of any component located at the first end. If the pressure sensor or primary seal is damaged, for example, a new pressure sensor or primary seal may be installed without having to replace the entire apparatus. The secondary seal also prevents fluid from a high pressure pipeline that has compromised the primary seal from being ejected from the pipeline. The secondary seal also prevents pipeline media from migrating through the electrical cable to a non-hazardous location.

Pressure sensor with secondary seal

A variable pitch fan in which the pitch of the fan blades is varied under control of a controller according to the speed of the fan. The controller is programmed to respond to increased fan speed by decreasing pitch of the fan blades. The variable pitch fan has a piston extending axially from a main shaft, about which main shaft a fan blade hub rotates. A pitch shifter is mounted on a cylinder, which itself is mounted on the piston. The pitch shifter is actuated by hydraulic fluid supplied through the main shaft to the cylinder. The piston is preferably axially stationary in relation to the main shaft. The cylinder is secured against rotational movement by cooperating out of round surfaces. Grease for the pitch shifter is supplied through the guide pin. One guide pin may be used for grease supply, while another may be used for excess grease return. Cooling of a pitch shifter may be accomplished using a heat sink mounted within the fan hub, preferably in a fan configuration, to conduct heat away from the cylinder into air rotating within the fan hub. Counterweights are mounted on each fan blade of a variable pitch fan, preferably hydraulically actuated, in a position which generates a torque opposite in direction to torque generated by the fan blades. The counterweights may be overbalanced, underbalanced, or balanced.

Variable pitch fan

A variable pitch fan in which the pitch of the fan blades is varied under control of a controller according to the speed of the fan. The controller is programmed to respond to increased fan speed by decreasing pitch of the fan blades. The variable pitch fan has a piston extending axially from a main shaft, about which main shaft a fan blade hub rotates. A pitch shifter is mounted on a cylinder, which itself is mounted on the piston. The pitch shifter is actuated by hydraulic fluid supplied through the main shaft to the cylinder. The piston is preferably axially stationary in relation to the main shaft. The cylinder is secured against rotational movement by at least one guide pin passing into the main shaft. Grease for the pitch shifter is supplied through the guide pin. One guide pin may be used for grease supply, while another may be used for excess grease return. Cooling of a pitch shifter may be accomplished using a heat sink mounted within the fan hub, preferably in a fan configuration, to conduct heat away from the cylinder into air rotating within the fan hub. Counterweights are mounted on each fan blade of a variable pitch fan, preferably hydraulically actuated, in a position which generates a torque opposite in direction to torque generated by the fan blades. The counterweights may be overbalanced, underbalanced, or balanced.

Growing community of inventors

Edmonton, Canada

Brian J Bruchal