Abstract: A weighing apparatus includes a SAW oscillator and a “push oscillator” to force the SAW oscillator into a desired mode of operation. A SAW temperature oscillator and a thermistor are also provided. The frequency of the “push oscillator” is made immune to temperature changes by generating it via a mixer mixing the SAW temperature oscillator with an adjustable fixed frequency oscillator. Long term stability of the SAW temperature oscillator is achieved by periodic calibration with the thermistor.

Abstract: A weighing apparatus includes a base (12) supporting a cantilevered elastic member (14) bearing a load platform (16). The interior of the elastic member (14) is hollowed and is provided with first (20) and second (22) piezoelectric transducers mounted on respective opposed posts. The transducers are arranged substantially parallel to each other with a small gap between them and are coupled to an amplifier (950, 952) to form a “delay line” and a positive feedback loop, to form a natural oscillator.

Abstract: A method and system for monitoring process parameters associated with a manufacturing or testing process. The system includes: at least one machine which is used in the manufacturing or testing process; at least one sensing device, coupled to the at least one machine, for measuring a process parameter associated with the at least one machine; and a controller, coupled to the at least one sensing device, for receiving and storing measured data from the at least one sensing device. The method includes the acts of: measuring a value of a process parameter associated with a machine used in the manufacturing or testing process; converting the measured value of the process parameter into a digital data signal having a specified data format; transmitting the digital data signal to a controller; and storing the digital data signal in a database.

Abstract: A weighing apparatus includes a base supporting a cantilevered elastic member bearing a load platform. The interior of the elastic member is hollowed and is provided with first and second piezoelectric transducers mounted on respective opposed posts. The transducers are arranged substantially parallel to each other with a small gap between them and are coupled to an amplifier to form a “delay line” and a positive feedback loop, i.e. a natural oscillator.

Abstract: An electronic weighing device includes a lower base plate, an upper load bearing plate, and a load cell coupled to central portions of the upper and lower plates such that the load cell responds to weight on the bearing plate. The upper and lower plates are each notched at a central location, with the notches being offset from each other. The overlapping portions of the notches form a cavity for a central portion of the load cell, The load cell is tapered or reduced in height at opposite ends thereof so that its ends fit between a notched portion of one of the upper and lower plates and a full-thickness portion of the other of the upper and lower plates. The reduced height ends of the load cell are coupled to the upper and lower plates.

Abstract: A weighing apparatus includes a base supporting a cantilevered elastic member bearing a load platform. The interior of the elastic member is hollowed and is provided with first and second piezoelectric transducers mounted on respective opposed posts. The transducers are arranged substantially parallel to each other with a small gap between them and are coupled to an amplifier to form a "delay line" and a positive feedback loop, i.e. a natural oscillator.

Abstract: An electronic weighing device includes a lower electrically conductive plate, an upper electrically conductive plate, a load cell coupled to central portions of the upper and lower plates such that the load cell responds to weight on the upper plate, and a flexible, conductive band coupling the periphery of the upper plate to the periphery of the lower plate. An electronic circuit is coupled to the load cell. The circuit is provided on a board which is mounted on the lower plate close to its center. A pair of bores are provided in the lower plate extending from the circuit board to an edge of the lower plate. A pair of non-conductive rods are coupled to potentiometer on the circuit board. The non-conductive rods extend through the bores from the circuit board to the peripheral edge of the lower plate. The lower plate is provided with a shielded electrical socket which is coupled by shielded cable to the circuit board. A conductive cover is provided over the upper plate, the load cell, and the band.

Abstract: An electronic weighing apparatus includes a base which supports a cantilevered elastic member upon which a load platform is mounted. The free end of the elastic member is provided with a first piezoelectric transducer and a second piezoelectric transducer is supported by the base. Each transducer includes a substantially rectangular piezoelectric substrate and a pair of electrodes imprinted on the substrate at one end thereof. The transducers are arranged with their substrates substantially parallel to each other with a small gap between them and with their respective electrodes in relatively opposite positions. The electrodes of the second transducer are coupled to the input of an amplifier and the output of the amplifier is coupled to the electrodes of the first transducer. The resulting circuit is a positive feedback loop with a "delay line" in which a surface acoustic wave in one substrate is effectively induced into the other.

Abstract: The present invention provides a system for transmission loss comparison.On embodiment of the present invention compares the transmission losses through optical paths through a first solution and a second solution. This embodiment includes first and second light sources for transmitting light through the first and second solutions. Also provided are first and second light detectors corresponding to the first and second light sources, and comparison means for comparing the outputs of the two detectors in order to determine which solution is darker.In addition, this embodiment includes a common gain balance configuration means for calibrating the relative gain of the two light detectors in order to compensate for signal differences between each source/detector path arising from various mechanical or optical factors. Further included is a dark solution compensation bias to compensate for differences between each source/detector path arising from spectral differences between the two light sources.

Abstract: A system for transmission loss comparison permits enhanced accuracy over a wider dynamic range by providing a reference channel including a transmitter, receiver, and transmission path therebetween, and a sample channel, including a transmitter, receiver, and transmission path therebetween. A feedback arrangement is provided for adjusting the outputs of both of the reference and sample transmitters in relation to the signal output of the reference receiver, so as to produce a desired signal level of the reference receiver's output over a given dynamic range, so as to compensate for loss over the reference transmission path. In this way, a comparator connected to the outputs of the two receivers receives inputs that are compensated for effects of losses over the reference transmission path.