Abstract: A transmitter for an alignment system in which a field of electromagnetic radiation is propagated in a non-planar reference cone is disclosed. The transmitter includes a source for providing a collimated beam of electromagnetic radiation directed parallel to a beam axis. A cantilever strand supports a bob within the beam. The bob has a conical reflecting surface to reflect the collimated beam conically. Optimally, the cantilever strand and bob are chosen to provide a deflection between the bob and plumb which is substantially one-half of any angular error between the beam axis and plumb. In an especially preferred form, a housing surrounds the bob and has inner and outer surfaces which minimize temperature effects on the orientation of the reference plane. Also, detectors are provided to sense when the angular error between the beam axis and plumb is outside of an acceptable range.

Abstract: A sealed rotary compressor is provided which includes separate pump and gear chambers. Disposed within the pump chamber is a set of rotors operatively associated with a set of gears rotatably mounted within the gear chamber. A substantially pressure differential exists between the two chambers. Rotational power is applied directly to the rotors through a static seal rather than through the gears which are utilized primarily to transmit the dynamic load. The pump chamber is defined by two end plates with a surrounding thin-walled housing. Within the pump chamber are interior thin wall members with the rotary members disposed therebetween and defining inlet and outlet pockets operatively associated with a pump housing inlet and outlet means.

Abstract: A mounting system for a laser diode enables adjustment of the location of the diode and of the direction of the diode's beam. Fine adjustments may be made of the location of the diode in side-to-side, up-and-down, and forward-and-back directions as well as rotationally for azimuth and tilt angle. A mounting fork is connected to a frame for movement side-to-side on the frame, with two spaced prongs of the fork extending generally vertically. A diode holder block containing the diode is positioned between the prongs and has cylindrical, generally arcuately convex vertical edges engaged between the generally planar surfaces of the forked prongs. This enables the block to be moved for adjustment by sliding and rotational manipulation up-and-down, forward-and-back, rotationally about a vertical axis for azimuth, and rotationally about a generally transverse horizontal axis for tilt.

Abstract: A scanning apparatus and method for scanning a beam of light incorporate an optical system in which a rotatable wheel has a plurality of light deflecting facets on the periphery of the wheel. The incoming light beam is reflected by a routing mirror or a routing beam splitter cube onto a front face of a facet as that facet is rotated in line with the routing element. The beam is deflected as it makes its first pass through the facet, and a porro prism redirects the deflected beam back through the rotating facet so that the beam makes two passes through each facet rotating past the routing element. The scanning action is produced by the rotation of the facet in the path of both passes of the beam through the facet. The net result cancels the angular motion of the beam in one direction and adds to the angular motion in the orthogonal direction. Scanning action as produced by one facet is repeated for each facet located on the periphery of the wheel.

Abstract: This invention provides a method for controlling the path of a crop spraying aircraft in making repeated traverses over a field to insure that each traverse is laterally spaced from the adjacent traverse by the proper distance to assure adequate coverage of the crop land with the material being sprayed and avoiding over-lapping or insufficient coverage of any portion of the crop land. In accordance with the method of the invention, the crop spraying aircraft carries a rotating laser beam transmitter and receiver, and the transmitted beam is reflected from a plurality of reflectors located on the ground at known positions relative to each other to provide successive reflections of the transmitted laser beam from which the angular positions of the aircraft relative to the reflectors may be continuously determined.

Abstract: A lightweight, portable laser beam level instrument has an optical path which includes a solid state light source; a pendulous, positive lens; a rotatable pentaprism or mirror equivalent; and a glass plate which is tilted to provide fine tuning. The level instrument also includes a damping mechanism, a waterproof enclosure and a clip-in battery pack.The solid state light source is a diode in a specific embodiment and produces an intense beam of rapidly diverging infrared laser light.The postiive lens is suspended below the diode at approximately the focal length of the lens from the diode to collimate the light. The pendulous suspension lens maintains the beam in a truly vertical position with respect to the earth to provide self-leveling in a limited range of movement of the instrument. The pentaprism or equivalent converts this vertical beam to a horizontal beam.

Abstract: A system is disclosed for controlling the plane of a laser beam in either horizontal, vertical or selected grade angle attitudes. The system includes an assembly comprising a housing which carries the operative components in a water-tight enclosure. The laser beam is generated by a laser tube carried on a chassis which is mounted for a limited range of universal movement about orthogonally intersecting Y and X axes by means of a gimbal frame. Optics structure is provided to route the beam in a collimated path along a Z-axis longitudinally of the chassis. A beam reflector unit rotatably mounted on an end of the chassis reflects the beam in a plane orthogonal to the Z-axis through a lighthouse structure provided in an end of the housing. The system for controlling the beam plane attitude includes three level sensing vials which are carried on the chassis, as well as a pair of Y- and X-axis motors and associated drive trains.

Abstract: A grade rod and method of operation for use in a surveying system employing a laser beam which is rotated in a plane. A flexible tape formed with a graduated scale is mounted for movement in a loop within the housing. A slider on the tape carries a pair of closely spaced-apart light detectors as well as electronic circuitry which discriminates between laser beam pulses and sunlight. Output signals from the circuitry on the slider are fed into a control circuit in the housing through a flexible cable which is carried in a traveling loop. Scale indicators are mounted for movement with the slider along a fixed scale which is provided on the housing, and a manually operated cursor is mounted for movement along the housing. The control circuit includes means for driving the tape and slider in a search mode until a light pulse from the laser hits a detector, and then in a track mode for centering the detectors on the plane of the laser beam.