Abstract: A pressure sensor package and a method of producing the same. The package includes a pressure sensor base, a pressure sensor diaphragm positioned over the base, and a sealing ring positioned over the pressure sensor diaphragm and creating an interference fit with the pressure sensor base. The sealing ring forms a mechanical interference with the pressure sensor base by either positioning the ring within an under cut in a sidewall of the base or deforming a portion of the base over the top of the ring. The pressure sensor base includes a recess having a bottom surface and a groove in the bottom surface, and the sealing ring and/or the pressure sensor diaphragm is positioned within the groove. The package further includes external threads for securing the package to a threaded orifice, the external threads being positioned on the output side of the package, as defined by the diaphragm.

Abstract: An apparatus including an inner member mounted for rotation about an axis, an outer member mounted for concentric rotation about the inner member relative to the axis, the outer member having an inner surface adjacent the inner member and an outer surface, and a sensor mounted adjacent the outer surface of the outer member so as to measure the rotational speed of the inner member.

Abstract: A method and apparatus for remotely measuring the pressure and temperature of gas in a vehicle wheel. The vehicle includes a frame member and a vehicle wheel mounted for rotation relative to the frame member about a rotation axis. A transmitting circuit is mounted on the frame member. The transmitting circuit includes a transmitting coil and generates electrical energy in the transmitting coil. A receiving circuit is mounted on the vehicle wheel for movement therewith such that, as the vehicle wheel rotates relative to the frame member, the receiving circuit is inductively coupled to the transmitting circuit. The receiving circuit includes a sensor for generating a data signal corresponding to a physical characteristic of the vehicle wheel and a wireless communication circuit for receiving the electrical energy from the transmitting coil to remotely power the receiving circuit and for transferring the data signal from the receiving circuit to the transmitting circuit.

Abstract: A method of securing a pressure sensor diaphragm to a pressure sensor base, including the steps of positioning the pressure sensor diaphragm over the pressure sensor base, placing a pressure sensor cap over the pressure sensor diaphragm, applying a tensile force to at least a portion of the cap, and deforming a portion of the cap around a portion of the base. The applying step can occur before the deforming step by engaging a portion of the cap and advancing the base toward the cap to create tension in a portion of the cap. This creates a tensile preload in the cap. The applying step can instead be performed during the deforming step by engaging a first portion of the cap and advancing a second portion of the cap toward the first portion of the cap and around a portion of the base. This can create tension in a portion of the cap when the deformation operation is being performed.

Abstract: A temperature sensor using doped polysilicon resistors in a bridge configuration, an amplifier, and a doped polysilicon feedback resistor between the input and the output of the amplifier. The polysilicon resistors are doped with selected concentrations of impurities such as boron, phosphorus, arsenic or antimony. The resistors are doped to establish predetermined temperature coefficients so that the resistors exhibit a predetermined temperature dependence. This temperature dependence is utilized to create a temperature sensor that is stable, accurate, and rugged and that has a generally linear output to temperature response.

Abstract: An electronic gain circuit adapted to receive an input signal, an amplifier having a gain for amplifying the input signal to produce an output signal, and biasing resistors connected to the amplifier to automatically adjust the gain of the amplifier in response to fluctuations in ambient temperature such that the output signal of the amplifier responds to ambient temperature fluctuations.

Abstract: A pressure sensor including a housing having an interior surface forming a cavity, and a fill passageway communicating with the cavity. The fill passageway has opposite ends defining an axis extending between the ends, and one of ends defines a fill port spaced from the cavity. A pressure transducer is mounted on said interior surface. The pressure sensor also includes a sealing member moveable across the fill port in a direction transverse to the axis between a first position allowing fluid flow through the fill passageway and a second position closing the fill passageway such that the fluid is sheared off at the fill port to seal said cavity. Preferably, the fluid pressure within the cavity before sealing is substantially equal to the fluid pressure within the cavity after sealing.

Abstract: A sensor for detecting the angular velocity of a rotating member. The sensor includes a bobbin having an exterior defining an annular recess and a coil within the recess. The bobbin also has a generally cylindrical aperture and supports a probe and a permanent magnet in the aperture. The housing is secured to the bobbin and the housing and bobbin include tapered inner and outer surfaces, respectively, that are made to form a wedge fit seal between the bobbin and the housing to prevent the introduction of molding material during the overmolding process. The bobbin also includes supports for supporting the lead wires extending between the coil and the terminals.

Abstract: A sensor for determining the rotational speed of a rotating element. The sensor includes a giant magnetoresistive ratio sensing device which is magnetically coupled to the rotating element and includes an output terminal. The sensing device generates an output signal at the output terminal having a frequency corresponding to the rotational speed of the rotating element. A wave-shaping circuit is connected to the output terminal for receiving the output signal and for generating a digital switching signal having a frequency equal to the frequency of the output signal. A frequency divider has an input connected to the wave shaping circuit for receiving the digital switching signal. The frequency divider generates, in response to the digital switching signal, a square wave output having a 50% duty cycle and a frequency equal to the frequency of the digital switching signal divided by a predetermined divisor.

Abstract: A sensor for detecting the angular velocity of a rotating member. The sensor includes a bobbin having an exterior defining an annular recess and a coil within the recess. The bobbin also has a generally cylindrical aperture and supports a probe and a permanent magnet in the aperture. The housing is secured to the bobbin and the housing and bobbin include tapered inner and outer surfaces, respectively, that are made to form a wedge fit seal between the bobbin and the housing to prevent the introduction of molding material during the overmolding process. The bobbin also includes supports for supporting the lead wires extending between the coil and the terminals.

Abstract: A method of forming apparatus including a force transducer on a silicon substrate having an upper surface, the silicon substrate including a dopant of one of the n-type or the p-type, the force transducer including a cavity having spaced side walls and a diaphragm supported in the cavity, the diaphragm extending between the side walls of the cavity, comprising the steps of: a. implant in the substrate a layer of a dopant of the one of the n-type or the p-type; b. deposit an epitaxial layer on the upper surface of the substrate, the epitaxial layer including a dopant of the other of the n-type or the p-type; c. implant spaced sinkers through the epitaxial layer and into electrical connection with the layer of a dopant of the one of the n-type or the p-type, each of the sinkers including a dopant of the one of the n-type or the p-type; d. anodize the substrate to form porous silicon of the sinkers and the layer; e. oxidize the porous silicon to form silicon dioxide; and f.

Abstract: A gas concentration sensor for use in a closed container having a constant volume and gas within the container, wherein the gas has a known pressure at a given temperature. The sensor includes a pressure sensing device disposed within the container, wherein the pressure sensing device generates a first electrical signal functionally related to the gas pressure within the container. The sensor also includes an electronic circuit connected to the pressure sensing device which amplifies the first electrical signal and produces a second electrical signal functionally related to the gas concentration within the volume at any temperature.

Abstract: A temperature sensor assembly for measuring ambient temperature and including a housing defining an enclosure. A temperature sensor is mounted within the enclosure. The housing includes a brass cap and a liner for conducting heat from the brass cap to the temperature sensor. The temperature sensor is mounted on the brass liner and is electrically insulated from the brass liner by a thermally conductive material.

Abstract: A sensor for detecting the angular velocity of a rotating member. The sensor includes a bobbin having an exterior defining an annular recess and a coil within the recess. The bobbin also has a generally cylindrical aperture and supports a probe and a permanent magnet in the aperture. The housing is secured to the bobbin and the housing and bobbin include tapered inner and outer surfaces, respectively, that are made to form a wedge fit seal between the bobbin and the housing to prevent the introduction of molding material during the overmolding process. The bobbin also includes supports for supporting the lead wires extending between the coil and the terminals.

Abstract: The invention provides a method and apparatus for detecting maxima and minima of an array of data points defining a periodic, symmetrical waveform. The method comprises comparing the "y" values of two marker points (selected from the array of data points), which marker points are spaced apart along the waveform by a predetermined number of data points. If the "y" values of the two marker points are not substantially the same, both marker points are incremented in the "x" direction, and their "y" values are tested again. If the "y" values are substantially the same, within a predetermined tolerance value t, a positive or negative peak has been found. Optionally, the points between the marker points are then sorted to find the tip of the peak.

Abstract: A bearing assembly for a vehicle including a fixed element, a rotating element rotating relative to the fixed element about an axis, and an annular sensor connected to one of the fixed element and the rotating element. The sensor includes a pick-up coil and an annular magnet connected to the pick-up coil. The magnet has a plurality of magnetic regions which alternate in polarity around the magnet. The magnet generates a magnetic flux path magnetically coupling the magnet to the coil and resulting in the generation of an electrical signal in the coil. The rotating bearing element includes a plurality of gear teeth. The gear teeth generate a change in the reluctance of the magnetic flux path to vary the electrical signal in response to the angular speed of the fixed element relative to the rotating element.

Abstract: A transducer for generating an amplified signal in response to a stimulus. The transducer includes a sensing structure for sensing a stimulus and for generating a signal functionally related to the stimulus. An amplifier circuit, utilizing a single amplifier, amplifies the signal by a predetermined gain. Resistive elements in the amplified circuit are formed on the same substrate as the sensing structure and define the predetermined gain of the amplifier circuit. The transducer generates a signal having zero magnitude in response to zero pressure on the sensing structure and has fewer than seven resistors requiring laser trimming.

Abstract: A cold start air control device for an internal combustion engine of the type having an air delivery system in which the delivery of air to a vacuum generating manifold is controlled by a throttle valve and a by-pass valve and parallel with the throttle valve includes a casing that defines a passageway in parallel with the throttle valve and the by-pass valve and which has a cross-sectional area greater than that of the by-pass valve so as to offer a less restricted air flow path than that offered by the by-pass valve. The passageway provides communication between the manifold and atmosphere and a valve is disposed within the passageway for opening and closing the passageway in response to the vacuum level generated by the manifold.

Abstract: Sensor circuitry is disclosed for a transducer (32) having a sensor or delta coil (66) for generating a magnetic flux through a path of movement of a magnetically permeable piston member (48), such that movement of the member (48) changes the return coupled flux linkage, which flux change indicates movement of the member (48), and having a reference coil (84) spaced sufficiently from the path of movement of the member (48) such that movement of the latter has less affect on return coupled flux linkage of the reference coil (84) than the delta coil (66). The coils (66 and 84) are connected (204) in respective parallel voltage dividers, and a half-wave rectified AC signal (diode CR11) is applied thereto.

Abstract: A variable reluctance magnetic speed sensor senses the speed of a rotating gear (12). A ferrous outer cylindrical shell (22) extends axially and has a magnet (14) at one axial end and a coil (16) at the other axial end. An inner pole piece (4) in the coil (16) directs magnetic flux across a gap to the gear teeth (10), which flux is returned by the outer pole piece shell (22) to the magnet (14). Particular pole piece gap spacings are disclosed together with various pole piece constructions.