Abstract: A truck scale has a weighbridge built with two parallel beams for carrying the wheels of a truck. The beams are laterally interconnected, and are each narrower than half the width of the weighbridge, so there is a gap at the center between the beams. Each beam rests directly on load cell devices supported by foundation members. In very long scales each beam is composed of shorter sections, each supported by a pair of load cell devices. The gap in the center of the weighbridge is covered by removable cover plates or blocks, which may have side walls extending above the beams to limit the lateral travel of truck wheels on the scale.

Abstract: Weighing of railway cars is accomplished by replacing a short section of fixed rail with a weigh-rail, and supporting the weigh-rail as well as sections of the fixed rail near the weigh-rail on an added foundation structure. The weigh-rail has a weigh-rail body for supporting the wheels of the railway car, and two dual shear beam load cells arranged transverse to the weigh-rail body. The weigh-rail is supported on the foundation structure solely by the four ends of the two dual shear beam load cells, and bumpers are arranged adjacent the ends of the load cells for maintaining the weigh-rail body aligned with the fixed rail ends. Bumpers are also arranged to prevent one end of the weigh-rail from flipping upwards when a railway car wheel enters the other end of the weigh-rail.

Abstract: A strain gage transducer system, such as a load cell based weighing system, is protected against moisture related errors by an electrically conducting guard circuit for terminals and other parts subject to wet or humid conditions. The guard circuit is connected to an electrical potential close to a potential of signal terminals in a strain gage bridge, for instance to a center tap in a power supply for the strain gage bridge.

Abstract: A weighing method for a wheel supported load, such as a hospital bed, uses a weighing device having a base with a flat bottom surface, and a track surface for a wheel arranged parallel to the bottom surface. The track surface is supported on an arrangement for sensing weight which includes a pair of cantilever bending beams with strain gages, and one end of the track surface extends beyond the end of the flat bottom surface. To start weighing, the weighing device is first tilted, so the track surface can be wedged between a wheel and the floor. In this position the track surface acts as a ramp for the wheel. The wheel is next rolled up onto the track surface until it is above the front edge of the flat bottom surface. At this point the weighing device will flip over by gravity to rest on the flat bottom surface, and the weighing of the load can be done without risk for force shunting to the floor. A weighing device suitable for use with the method is also disclosed.

Abstract: A strain gage load cell is adjusted to zero output signal at no load or a fixed tare load on the load cell independent of the load cell temperature by shunting a pair of opposing arms of the strain gage bridge by equal resistors, and connecting a pair of equal resistors between opposite terminals of the power supply for the strain gage bridge and opposite corners of the output terminals of the strain gage bridge. The zero adjustment according to the invention is especially useful with load cell arrangements where individual strain gage elements must have equalized sensitivities.

Abstract: A compression type load cell is provided consisting of a self-stabilizing rocker pin symmetrical about a primary longitudinal axis for measuring a load force applied to the load cell. Strain gages mounted circumferentially around a center section of the rocker pin measure the compressive force corresponding to the load force. Also provided is a weighing apparatus comprising a weighbridge with horizontal load transmitting surfaces resting on a plurality of self-stabilizing rocker pin load cells supported by horizontal base surfaces.

Abstract: Location-representative signals are communicated to vehicles (12, 14, 16) by modifying existing traffic detector stations of the type utilizing an inductive coil (20) embedded in the roadway (22). Circuitry (44-52) is provided for generating a carrier signal modulated in accordance with a modulating signal representative of the location of an associated traffic detector station. A transformer (56) couples the modulated carrier signal into the existing inductive coil such that the coil establishes a magnetic field above the roadway which is modulated by the location representative signals. The vehicles have inductive coils (70) mounted thereon for sensing the modulated magnetic fields, and circuitry (72, 74, 76) for extracting the location-representative signals therefrom. The location-representative signals may then be, e.g., automatically transmitted to a central dispatching station (18).

Abstract: A method and apparatus for determining the weight of a railway supported vehicle. A pair of spaced apart rails which are engageable with wheels of the vehicle are supported by a longitudinally extending sleeper or tie member which extends transversely to the rails and which is disposed beneath the rails and extends outwardly of both sides of the rails. The longitudinal end portions of the sleeper member which are disposed outwardly of the pair of spaced apart rails are supported in a manner which allows deflection of the sleeper member in response to forces applied thereto by the rails. A means is provided for providing a signal which varies as a function of the strain in the sleeper, which means preferably measures either the shear strain or the bending strain in the sleeper. The signal is then processed to provide an indication of the weight of the vehicle supported on the rails.