Abstract:
An electrical weighing scale for measuring the weight of a user having has a substantially transparent platform, a plurality of supports, and a display assembly. Piezoresistive sensors, disposed in the supports, change resistance in response to a change in the weight applied to the scale. The piezoresistive sensors include piezoresistive elements arranged in a half bridge structure that has been calibrated to provide zero balance, span matching and impedance normalization. The sensors are coupled in parallel to a display. The parallel arrangements produces a composite output signal that enables any number of sensors to be used in the scales design.
Abstract:
A load cell for an electronic scale, which is capable of providing both load support and load measurement in a planar member. This is accomplished by configuring the load cell as a substantially flat circular plate having an E-shaped deflectable member defined therein. The E-shaped member includes three beams, at least one of which includes a sensor arrangement that responds to a load applied to the deflectable member by generating an electrical signal that is indicative of the load applied to the E-shaped member.
Abstract:
The present weight scale performs automated self calibration by periodically initiating a measurement operation to determine the zero offset from a true weight reading due the weight scale's intrinsic weight. The weight scale's intrinsic weight will vary due to changes in environmental conditions such as temperature and humidity, which impact the behavior of the internal electronics that perform the weight measurement operations. The automated self calibration is provided by a counter circuit, clocked by a low power oscillator, that periodically initiates the weight scale's electronics to undertake a weight measurement of the tare weight value of the scale. The tare weight value is stored in memory until replaced by a subsequent tare weight value calculation. During a weight measurement operation the gross weight measurement is deducted by the tare weight value stored in memory to arrive at a net weight representing a user's true weight.
Abstract:
An indoor/outdoor thermometer system employs a wireless infrared telemetry link. An outdoor unit capable of being mounted on or in proximity to a window is equipped with a processor and modulation means to enable measurement of outdoor temperature and conversion to modulated data pulses. The data pulses are coded to provide noise immunity. The data is transmitted in a free space infrared medium and detected by an indoor unit which displays the outdoor temperature. The indoor unit is mounted in a suitable convenient indoor location. Indoor temperature may also be measured and displayed. An internal timing data transmission feature is employed to drastically reduce power consumption, enabling long lasting lithium type batteries to be deployed as the power source.
Abstract:
A sensor plate for use in a load cell for use in an electronic scale comprising a planar first surface; a planar second surface opposite the first surface having a depression formed therein defining a flexure area; a load cavity formed in the second surface having a conical receptacle end for receiving a strut; and sensors disposed over the flexure area for generating a signal in response to a load applied to the loading cavity wherein the strut has a first conical projection end coupled to the conical receptacle end of the loading cavity and a second end coupled to a footer member such that the strut mechanically floats therebetween for providing the applied load at a substantially central position at the load cavity.
Abstract:
A load sensor plate (100) is adapted for manufacture by stamping spaced apart openings (110) through a thin blank to define flexure beams (112) beside the openings (110); and forming the blank with spaced apart columnar walls (102), (106) joined by a web (104) having the openings (110) and the flexure beams (112) whereby, an applied load (116) exerted on one of the columnar walls (102) is distributed among the flexure beams (12), and another of the columnar walls (106) bears an opposing force (118) that resists the applied load (118).
Abstract:
A foot assembly for a weighing scale comprises a base, a ring arranged in coaxial spaced relation to the base; and a plurality of deformable compensation beams projecting outwardly from a portion of the base so as to support the ring.
Abstract:
An electronic thermometer is particularly adapted for use as a fever thermometer and employs a unique temperature sensor configuration comprising a platinum temperature sensing resistor and tantalum nitride reference resistor both mounted on the same substrate. The resistors are selectively coupled to the input of a dual ramp integrator forming part of an analog to digital converter. Digital control circuitry causes the sensing resistor to be coupled to the input of the integrator during a first mode and causes the reference resistor to be coupled to the input during a second mode. Included in the digital circuitry is a first sensor memory and a second reference memory. These memories have stored therein a digital number indicative of the response of both resistors at a predetermined temperature obtained during initial calibration of the sensor and thermometer. The stored values are compared during the respective mode with the accumulated count in a clock counting circuit. If a match occurs the electronics advance the sequence to enable any excess count occurring during the second mode to be monitored and eventually displayed as manifesting the measured temperature. The digital electronics controls the measurement process in a sequential manner to assure accuracy and stability of the final reading. The circuitry enables a display of the last measured temperature prior to making a new measurement, and further includes circuitry for monitoring the level of a lithium battery source which is permanently sealed within the unit and to permanently disable the unit when the source is no longer capable of providing sufficient voltage to secure accuracy.While a fever thermometer for home or hospital use is disclosed, the techniques are applicable for other types of temperature measurements; such as laboratory equipment, monitoring, laboratory and industrial controllers, indoor or outdoor thermometers for the home or office.
Abstract:
A foot assembly for a weighing scale comprises a base, a ring arranged in coaxial spaced relation to the base; and a plurality of deformable compensation beams projecting outwardly from a portion of the base so as to support the ring.
Abstract:
A load sensor plate (100) is adapted for manufacture by stamping spaced apart openings (110) through a thin blank to define flexure beams (112) beside the openings (110); and forming the blank with spaced apart columnar walls (102), (106) joined by a web (104) having the openings (110) and the flexure beams (112) whereby, an applied load (116) exerted on one of the columnar walls (102) is distributed among the flexure beams (12), and another of the columnar walls (106) bears an opposing force (118) that resists the applied load (118).