Abstract: A surface measurement method includes inspecting a plurality of samples of a first irregular workpiece surface in two dimensions, determining, based on the inspections of the samples, a total number of surface peaks on each of the plurality of samples, and deriving a control limit from a statistical variation of the total number of surface peaks on each of the samples. The control limit specifies an out-of-tolerance condition for the total number of surface peaks on a second irregular workpiece surface. The method further includes inspecting a portion of the second irregular workpiece surface in two dimensions, determining, based on the inspection of the portion of the second irregular workpiece surface, a total number of surface peaks on the portion, and comparing the total number of surface peaks on the portion to the control limit to determine whether the second irregular workpiece surface is in the out-of-tolerance condition.

Abstract: A surface measurement method includes inspecting a plurality of samples of a first irregular workpiece surface in two dimensions, determining, based on the inspections of the samples, a total number of surface peaks on each of the plurality of samples, and deriving a control limit from a statistical variation of the total number of surface peaks on each of the samples. The control limit specifies an out-of-tolerance condition for the total number of surface peaks on a second irregular workpiece surface. The method further includes inspecting a portion of the second irregular workpiece surface in two dimensions, determining, based on the inspection of the portion of the second irregular workpiece surface, a total number of surface peaks on the portion, and comparing the total number of surface peaks on the portion to the control limit to determine whether the second irregular workpiece surface is in the out-of-tolerance condition.

Abstract: A rotary union assembly for an automatic tire inflation system for maintaining the pressure in the tires on a tractor trailer or other vehicle having a source of pressurized air for communication with the tires. The assembly communicates the tires with the air source through the axle interior using a conduit having a rigid portion and a flexible portion that extends between a support in the axle spindle and a rotary union housing secured against the outside end surface of the hub cap so as to be outside the wheel lubrication compartment and rotatable with the hub cap. The two-component conduit allows for a durable seal with the support in the axle spindle and accommodates misalignment of the rotary union housing with the conduit support. Relief valves in the housing prevent excessive pressure buildups in the housing and in the hub cap in the event of an air leak.

Abstract: An assembly to be mounted in an axle spindle for communicating pressurized air to a rotary union in a tire inflation system. The assembly includes an arbor having an air flow channel extending therethrough, a flange intermediary of the arbor ends and an axially inclined portion proximate the flange. A sealing member is carried by the flange for forming a seal with the axle spindle. A split ring locking assembly is disposed about the inclined portion of the arbor that is comprised of a plurality of segments held by an expansible retention spring. The segments move radially outwardly upon the locking assembly being moved along the inclined arbor portion and engage the axle spindle, securing the plug assembly within the spindle. A fastening member threadably engages the arbor for urging the locking assembly along the inclined arbor portion to effect securement of the plug assembly within the axle spindle.