Abstract: The invention has the objective of offering a sensor that allows for measuring the pressure force of the springs on the carbon brushes as well as the actual brush pressure on its contact surface. This is obtained by measuring between the carbon brush, and there is limited space through its holder, and the contact surface and is therefore characterized by the fact that the sensor is thinner than 4 mm, and that it is provided with a target (4) which is suspended in the sensor (1) by means of a mechanically deformable section (3), and where the sensor is fitted with one or more strain gauges (2) that is/are set up as such that it can detect the shearing of the mechanical deformable measuring section under pressure. In contrast to the existing measuring sensors, the measuring strips also connect the suspension points of the mechanically deformable elements with the sensor and/or the suspended target or measuring point through which sensitivity increases and makes the sensor useful for such applications.
Abstract: The MEMS sensor of the invention has movable and fixed components for measuring acceleration in a rotational mode in a direction in-plane perpendicular to spring axis. The components include an element frame, a substrate, a proof-mass a spring connected to the proof-mass and to the substrate, and comb electrodes. The MEMS sensor is mainly characterized by an arrangement of the components causing an inherent sensitivity for measuring accelerations in a range covering longitudinal and transversal accelerations. One or more of the components are tilted compared to the element frame. The semiconductor package of the invention comprises at least one MEMS sensor.
Abstract: A vibrator (electronic device) includes: a vibrator element including vibrating arms; a base portion supporting the vibrator element and having a rectangular shape in a plan view; and a lid provided on the side of the vibrator element opposite to the base portion 3. Extending directions of long and short sides of the base portion and an extending direction of the vibrating arms cross each other. When an angle formed by the vibrating arms and a Y-axis direction is ?, the angle ? is more than 0° and less than 90°.
Abstract: A MEMS device comprises a substrate, a proof mass spaced apart from a surface of the substrate, and an over-travel stop structure. The over-travel stop structure includes a lateral stop structure and a cap coupled to the lateral stop structure. The MEMS device is fabricated to include relatively small gap sections and relatively large gap regions separating the lateral stop structure from the proof mass. The larger gap regions are covered by the cap and the smaller gap sections are exposed from the gap. During fabrication, removal of particles from the smaller gap sections is facilitated by their exposure from the cap and removal of particles from the larger gap regions underlying the cap is facilitated by their larger size. The lateral stop structure may be cross-shaped to limit deflection of the proof mass along two in-plane axes. The cap limits deflection of the proof mass along an out-of-plane axis.
January 22, 2015
Date of Patent:
May 2, 2017
NXP USA, Inc.
Jun Tang, Chad S. Dawson, Andrew C. McNeil
Abstract: An accelerometer has E-shaped resilient beams to isolate stress and reduce deformation. A top cap silicon wafer and a bottom cap silicon wafer are both coupled with a measurement mass to form a capacitor. The measurement mass has a mass, range-of-motion stops, and resilient beams located within a support frame. The range-of-motion stops are coupled to the support frame by connection beams, and the mass is coupled with the range-of-motion stops by groups of E-shaped resilient beams. The ends of each resilient beam are connected to the range-of-motion stops, and the middle of each resilient beam is connected to the mass.
September 18, 2015
Date of Patent:
January 31, 2017
Chinese Academy of Science Institute of Geology and Geophysics
Du Li Yu, Lian Zhong Yu, Chang Chun Yang
Abstract: A semiconductor acceleration sensor with a reduced cross axial sensitivity, which is easily manufacturable. In this semiconductor acceleration sensor, two sensor units are provided on two cantilever beams which have the identical shape and are arranged on the same plane in mutually opposite orientations, and a bridge circuit is formed by the piezoresistors of these two sensor units, such that the cross axial sensitivity of the semiconductor acceleration sensor can be reduced significantly. The bridge circuit to be formed can be a half bridge circuit, or a full bridge circuit in which case the piezoresistors of the second sensor unit are arranged to be oriented along a direction perpendicular to that along which the piezoresistors of the first sensor unit are arranged to be oriented. This semiconductor acceleration sensor can be manufactured monolithically on a single semiconductor substrate, or from separately manufactured acceleration sensors.
Abstract: The fixed end of an acceleration detection beam of a semiconductor acceleration detecting apparatus is mounted onto a board through a supporting base. A weight for increasing the sensitivity to acceleration is disposed on the free end of the acceleration detection beam. A limit stop for limiting excessive displacement of the weight in two directions surrounds part of the weight. Therefore, the displacement of the weight can be controlled with a high degree of accuracy. Resistance to impact is also improved.
Abstract: A semiconductor acceleration sensor has an acceleration sensor element on which gauge resistors are arranged so as to cancel sensed output component corresponding to any acceleration acting in a direction different from an acceleration to be sensed.
Abstract: A semiconductor accelerometer including a weight, a support frame surrounding the weight with a gap therebetween, at least one beam for connecting the weight to the support frame, a piezoresistor attached onto the beam for detecting acceleration, and stoppers for restricting the movement of the weight relative to the support frame, in which at least one first projection integrally mounted to the weight and at least one second projection integrally mounted to the support frame cooperate to function as the stoppers. At least one first cross member and at least one second cross member may cooperate with the first and second projections. First and second stopping members may also cooperate with the first and second projections.
Abstract: A batch method for fabricating semiconductor capacitive force transducers is disclosed wherein a first wafer of silicon or fused silica is recessed by etching to define an array of force transducer structures, each including a deflectable portion supported from a surrounding frame portion. The first wafer is thermoelectrically bonded between a pair of glass or quartz plates, each plate having an array of electrode structures for capacitively sensing deflection of the individual force transducers. Each electrode structure includes a lead portion passing over the frame portion of the transducers and being spaced from the frame to provide a gas communication passageway through the frame to the capacitive gap between the electrode structure and the deflectable portion of each transducer. The composite assembled wafers are notched along cleave lines generally outlining the individual transducer structures.
Abstract: An accelerometer fabricated from silicon which is responsive to the three orthogonal components of an applied force. A method is also disclosed for etching the accelerometer from a single silicon substrate. Three rectangular beams or cantilevers are formed each having vertical sidewalls lying in crystalline planes orthogonal to one another. Each of the beams is directly responsive to one of the three orthogonal force components.
Abstract: First to third frames are formed by etching to penetrate a silicon substrate on the substrate. A plurality of thin cantilevered beams are formed in different lengths by cutting by etching the substrate in the frames; the beams formed in the first frame are formed perpendicular to the surface of the substrate to bend only in the X-axis direction, parallel to the surface of the substrate; the beams formed in the second frame are formed perpendicular to the surface of the substrate to bend only in the Y-axis direction, parallel to the surface of the substrate; and the beams formed in the third frame are formed to bend only in the Z-axis direction, perpendicular to the surface of the substrate. Masses are formed at the free ends of the beams, and piezo resistance layers are formed at the fixed ends.
Abstract: A semi-conductor type accelerometer features the provision of four piezo resistors on the surface of a flexible beam which interconnects the main body portion with a weight or mass which is adapted to cause the beam to flex under the application of an accelerative force. The resistors are subject to essentially the same ambient conditions whereby thermally induced drift is obviated while a high output for a given amount of beam flexure is obtained.
Abstract: An electromechanical transducer is provided, and the process for making it, which utilizes a piezoresistive element or gage which is crystallinally the same as the base or substrate upon which it is supported. The gage of the invention is a force gage, and is derived from its substrate by etching in a series of steps which, ultimately, provide a gage with substantially reduced strain energy requirements, because the volume of the gage may be as small as 3.times.10.sup.10 cubic centimeters of stressed material. In its most preferred form, the element or gage is etched free of its substrate to provide, in effect, a "floating gage." This is achieved by defining the gage in its substrate or in material rigidly bonded to its substrate, etching away immediately adjacent material, and leaving the gage free in space, while supported at each end on the substrate.
Abstract: A silicon accelerometer employing the piezoresistive effect of single crystal silicon to measure the flexure of semiconductor beams supporting a semiconductor mass. In one embodiment a rectangular semiconductor center mass is supported at each corner by a semiconductor beam parallel to one side of the center mass and perpendicular to the adjacent beams, each of the beams having an implanted resistor at the stationary end thereof. The crystal planes and relative orientations of the resistors are selected so that two resistors always increase, and two always decrease their resistance by the same amount as the center mass is displaced, which allows them to be connected in a Wheatstone bridge having a symmetric differential output.
Abstract: An accelerometer comprising a sheet of silicon configured as an inertia plate separate from a support plate except at a pair of flexure sites spaced along an axis, each flexure site including a pair of flexures mutually offset so that upon acceleration in a direction perpendicular to the inertia plate the flexures partake of compound bending, and stress responsive resistors at said flexures positioned so that upon compound bending the resistors change resistance in the opposite sense.
Abstract: Information as to borehole inclination is provided by a pendulum in combination with an elastomeric material whose resistance varies with compression. The pendulum is arranged in a housing to compress the elastomer whenever the housing deviates from the vertical, or other predetermined attitude. The change in resistance is measured by a circuit including an ohmmeter and the pendulum and elastomer as conductive elements.