Patent abstracts

Citation

(2005), "Patent abstracts", Sensor Review, Vol. 25 No. 2. https://doi.org/10.1108/sr.2005.08725bad.007

Patent abstracts

Title: Vibration Sensing Touch Input DeviceApplicant: 3M Innovative Properties CoPatent number: WO2004104808Publication date: 1 December 2004

Disclosed is a touch input device that determines touch position by sensing vibrations propagating in a touch plate that are indicative of a touch to the touch plate. Vibration sensing devices such as piezoelectric sensors are used to sense the vibrations. Selecting the size, shape, placement position and orientation of the sensors on the touch plate can enhance sensitivity of the sensors to vibration and yield symmetric response with respect to the direction of vibration propagation. Also disclosed is a method of making a vibration sensing touch input device.

Title: Optical fiber infrasound sensorApplicant: Univ CaliforniaPatent number: US6788417Publication date: 7 September 2004

Keywords: Patents, Vibration, Vibration measurement, Sensors

Infrasound signals in the band 0.02-4Hz are sensed in the presence of ambient noise generated chiefly by wind as integrated pressure variations, which induce detectable changes in the optical path length, along optic fibers, typically extending from 100 to 1,000m. and more, arrayed at arbitrary geometries. Two fibers connected as a Michelson, Mach-Zehnder or equivalent interferometer, where one fiber is coupled to atmosphere while the other is not for being hermetically sealed in a tube, permit common mode rejection of noise from temperature changes and strain, including ground vibration. Because the optic fiber infrasound sensors are longer than the distance over which wind-induced pressure changes are coherent, the effects of wind noise on the sensing of infrasound is reduced, and signal-to-noise ratio is increased over a wide bandwidth.

Title: Apparatus and method for evaluating damping performance of vibration-damping devicesApplicant: Tokai Rubber Ind LtdPatent number: US6742381Publication date: 1 June 2004

A damping performance evaluation apparatus for damping devices including: a support member detachably supporting a damping device in a state enabling the device to exhibit a damping effect thereof; a hammer member for applying oscillation force to the device caused by gravitational descent to strike the device; a double-strike preventing member for preventing the hammer member from dropping a second time due to rebound after initially striking the device, to prevent double-strike of the device by the hammer member; a vibration sensor installed at a vibration zone caused to vibrate through oscillation force applied by said hammer member, for outputting an electrical signal in response to vibration at the vibration zone; and a sensing member for sensing a vibration mode in the vibration zone on the basis of an output of said vibration sensor. A damping performance evaluation method is also disclosed.

Title: Optical Detection Cell and Sensor Using One Such CellApplicant: Tisserand Jean-CaludePatent Number: WO2004099739Publication date: 18 November 2004

The invention relates to a cell for detecting the mechanical vibrations of an object. Said cell comprises a first photoemitter for emitting a light beam towards a side of said object, and two photoreceivers. Each photoreceiver has a detection surface which is arranged in such a way as to receive the light beam modulated by the cast shadow of the object. The photoemitter and the photoreceivers are distributed over an inner section of a hollow tube forming the structure of the cell, the object being placed in the vicinity of the centre of the section mentioned. The invention also relates to a vibration sensor comprising a plurality of cells according to one of the previous claims, said cells being mechanically associated in order to simultaneously detect the vibrations of a plurality of objects, and to a control module for individually controlling the operation of each cell. The inventive cell can be used in sensors for string instruments, in sensors for measuring the tension of a cable, etc.