Abstract: A silicon-based sensor includes a substrate, a sensor element, and a protective diaphragm mounting and covering the sensor element. The diaphragm is a silicon layer which, in a preferred embodiment, includes an etch-stop dopant. The etch-stop layer is sealed to the substrate so that the layer covers and mounts the sensor element to the substrate. The sensor is fabricated by forming a trough area in a surface of a silicon block (e.g., a silicon chip or wafer), treating the trough area with an etch-stop dopant (e.g., boron), depositing a sensor element onto the doped trough area, sealing at least the periphery of the doped trough area to a surface of a substrate (e.g., glass) so as to encapsulate the sensor element, and then etching away undoped regions of the silicon block so that the doped trough area remains as a protective diaphragm sealed to the substrate and covering the sensor element. It is also possible to form a bonding pad on untreated (e.g.

Abstract: An accelerator control apparatus for mounting in a motor vehicle for a "drive-by-wire" system. The apparatus provides a bias spring means to generate the "feel" of an accelerator pedal to the vehicle operator, a compression spring means provides frictional forces preventing extraneous pedal actuation and pedal sensor switch means for indicating the rotation position of the accelerator pedal from a first or normal position to any second position.

Abstract: A process for flush-mounting a silicon micromachined sensor for fluid flow measurements with an adjacent face of a substrate. The faces of the substrate and sensor, over which the fluid flow will pass, are disposed face down on a conformal surface. Adhesive is applied between the sensor and substrate to secure the sensor and substrate one to the other. Upon removal from the conformal surface, the faces are cleaned of adhesive and the electrical signal generating means of the sensor are connected with the signal processing means, for example, by wire bonding. In this manner, the sensor lies flush with the face of the substrate, avoiding interference with the fluid flow over the sensor face and, hence, maintaining sensitivity throughout the life of the sensor.

Abstract: A high pressure, fast response, pressure balanced reversible flow, solenoid control valve for use in such automotiove applications as electronic valve timing for internal combustion engines and adaptive braking systems. A pressure balanced bearing is connected to a moveable valve member forming a valve cavity therebetween which is at a first pressure. The moveable valve member is also connected to an armature means on the other side of the pressure balanced bearing in an armature cavity. The pressure on the opposite side of the valve member and in the armature cavity is at a second pressure. Thus, the moveable valve member is maintained in a pressure balanced condition and the solenoid then operates against any spring forces, inertia and the viscous effects of the fluid and not the pressure of the fluid. As the solenoid is energized, the armature moves the pressure balance bearing and the valve member to open the valve allowing fluid to flow from a valve inlet to the valve outlet.

Abstract: High resolution microstepping of an unipolar stepping motor is accomplished by applying from a look-up table the values of the SINE and COSINE of a given angle to the control circuit of a unipolar stepping motor. The difference between the present position and the desired position is calculated and depending upon the magnitude of the difference, the degree of microstepping is determined from four steps per ninety electrical degrees of motor rotation to thirty-two steps. By such selection, the positioning of the output shaft of the motor is smoothly and accurately accomplished.

Abstract: A dual stream thin edge orifice disk is defined as a disk having a pair of orifices positioned to direct the flow of fluid from the interior portion of a valve into two different streams. The dual streams may be parallel or typically diverge at an angle for directing the stream to two adjacent engine valves in the situation wherein the valve is in electromagnetic fuel injector for an internal combustion engine. To have the dual streams flow in a direction that is not parallel, the area of the disk surrounding the dual orifices is embossed and the orifices are positioned along the sides of the embossment between the base and the apex thereof. The manufacturing of the accurately sized orifices in the disk is accomplished by means of a progressive die. One of the stations of the die provides a coining operation on the orifice. Such coining operation is adjustable by means of a micrometer adjustment.

Abstract: An electronic throttle actuator is directly connected without an intervening gear train to a stepper motor for rotating the throttle valve from a first position, closed or substantially closed, to a second position which is wide open and any angular position therebetween. The movement of the throttle valve is under control of electronic control means which can locate the throttle valve at any one of a plurality of positions between the first and the second positions. The coupling between the motor and the shaft of the throttle valve provides for redundant means to close the throttle valve and connected to the shaft are a pair of redundant torsion springs for biasing the throttle valve in said first position. A second coupling directly connects the shaft of the throttle valve to a throttle position sensor. A pair of cavities are formed in the throttle body housing for enclosing both the coupling from the shaft to the motor and to the throttle position sensor and the redundant torsion springs.

Abstract: In a digital control system wherein control voltages are analog voltages, a method and control system for generating a variable output bit resolution from an N bit analog to digital converter utilizing a control circuit to control the input spread of the voltage references to the A/D converter. Depending on the binary value of the MSD position, the input reference voltage spread is controlled. If the binary value is zero, the input reference voltage spread is one-half the normal value and the resolution is N+1 bits and if the binary value is zero for both the MSD and MSD-1 positions, the input reference voltage spread is one-fourth the normal value and the resolution is N+2 bits and so on until the first binary one value is found after consecutive preceding binary zero values.