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US 5,203,207 AGranted
Raindrop sensor
AssigneeAisin Seiki Kabushiki Kaisha
InventorMasanori Sugiyama
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AssigneeAisin Seiki Kabushiki Kaisha
InventorMasanori Sugiyama
Estimating the term…
A raindrop sensor attached to a plate such as a windshield of a car. A first piezoelectric element as an ultrasonic generator is fitted to the plate via a first coupler. The coupler fixes the first element in an inclined state by a predetermined angle relative to the plate. Thereby, elastic waves or ultrasonic waves from the first element are transmitted while being repeatedly reflected in the plate. A second piezoelectric element as an electro-acoustic transducer is fitted to the plate via a second coupler. The second element detects amplitude of the ultrasonic waves transmitted in the plate.
A raindrop sensor provided on a plate, comprising:
A raindrop sensor provided on a plate, comprising:
A raindrop sensor provided on a plate, comprising:
A raindrop sensor providing on a plate, comprising:
A raindrop sensor provided on a window of a vehicle having an opaque coat, comprising:
Dependencies are inferred from the claim text.
Drawings are temporarily unavailable. Open the PDF at USPTO
By electric means: using piezoelectric devices
Including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like: characterized by the arrangement or…
Characterized by the arrangement or type of detection means: optical rain sensor
Analysing solids: by measuring attenuation of acoustic waves
Term ended 26 Oct 2010 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of the Invention
This invention relates to raindrop sensors for detecting amount of raindrops attached to a plate.
2. Description of the Related Art
The subject matter of the invention may be better seen in reference to the following description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram showing a first embodiment of a raindrop sensor of the invention.
FIG. 2 is an enlarged sectional view of an example of a wave transmitter.
Referring to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, a first preferred mode of a raindrop sensor of the invention will be described hereafter. While the sensor of the invention may be used in any sensing applications for detecting raindrops on a plate, it will be specifically described in this embodiment in an application to detection of raindrops on a front windshield of a car.
Referring to FIG. 1, a wave sender 12 is fixed on a front window glass or windshield 11 of a car. Preferably, the wave sender 12 is composed of a coupler 12a and an ultrasonic generator such as a piezoelectric element 12b that is stuck on the coupler 12a.
An oscillator circuit 13 is electrically connected with the piezoelectric element 12b. The circuit 13 provides alternating current signals of about 1 to 10 Mhz or 100 Mhz so as to cause the element 12b to generate vibration of ultrasonic waves 50. The element 12b is vibrated mostly in its thickness direction with A.C. power supply from the oscillator 13. The element 12b is adapted to vibrate to radiate the ultrasonic waves 50 as elastic waves into the coupler 12a.