Microprocessor based level and angle finder
First Claim
1. An angle sensor comprising:
- a. a housing having a reference point thereon;
b. gravity responsive means mounted in said housing and including an eccentrically weighted disc mounted for rotation on an axis in said housing, and radially extending discrete markings thereon around the disc concentric with said axis, each of which markings defines a positional relationship relative to a gravitational vector wherein said discrete markings on said disc comprise spaced-apart lines, each line representing two degrees of arc and each space representing two degrees of arc, said sensing means comprising first and second phototransistors spaced an odd number of degrees of arc apart to sense said spaces and said markings, and a third phototransistor positioned at a predetermined angular position from said first and second phototransistors for sensing gravitational alignment of the disc with reference to a zero degree reference marking on said disc;
c. sensing means stationarily mounted in said housing for sensing the passage of the markings on the disc as the housing moves in relation to said disc and the disc maintains a position corresponding to the gravitational vector;
d. means for determining the number of and direction of movement of the markings as the markings move past said sensing means, and computing the angular position of the reference point relative to the gravitational vector; and
e. display means for indicating the angular position of the reference point.
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Accused Products
Abstract
An angle finder (10) and level (40) are disclosed. The level (10) and angle (40) have digital displays (17) which provide a visual, numerical representation of the angular alignment of a reference surface in relation to a gravitational vector. Angle finder (10) and level (40) are controlled by a microprocessor (19). A disc enclosure (18) contains a rotatably mounted disc (23) on which is mounted a weight (26). Weight (26) keeps disc (23) in a relatively constant position relative to the gravitational vector. Also mounted in the disc enclosure (18) are photodetectors (27), (28) and (29). Disc (23) contains markings (30) which, in the disclosure of this application, each represent two degrees of arc. The three photodetectors (27), (28) and (29) sense the movement of markings (30) and by logical computation microprocessor (19) determines the angular alignment of the reference surface. In another embodiment of the invention, a disc enclosure ( 18'"'"') includes u-throat detectors (60), (61) and (62) which count the passage of markings (55) on a transparent disc (50) in the manner described above.
43 Citations
13 Claims
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1. An angle sensor comprising:
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a. a housing having a reference point thereon; b. gravity responsive means mounted in said housing and including an eccentrically weighted disc mounted for rotation on an axis in said housing, and radially extending discrete markings thereon around the disc concentric with said axis, each of which markings defines a positional relationship relative to a gravitational vector wherein said discrete markings on said disc comprise spaced-apart lines, each line representing two degrees of arc and each space representing two degrees of arc, said sensing means comprising first and second phototransistors spaced an odd number of degrees of arc apart to sense said spaces and said markings, and a third phototransistor positioned at a predetermined angular position from said first and second phototransistors for sensing gravitational alignment of the disc with reference to a zero degree reference marking on said disc; c. sensing means stationarily mounted in said housing for sensing the passage of the markings on the disc as the housing moves in relation to said disc and the disc maintains a position corresponding to the gravitational vector; d. means for determining the number of and direction of movement of the markings as the markings move past said sensing means, and computing the angular position of the reference point relative to the gravitational vector; and e. display means for indicating the angular position of the reference point. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. An angle sensor comprising:
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a. a housing having a reference point thereon; b. gravity responsive means mounted in said housing and including an eccentrically weighted disc mounted for rotation on an axis in said housing, and a single array of radially extending discrete markings thereon around the disc concentric with said axis, each of which markings defines a positional relationship relative to a gravitational vector; c. sensing means stationarily mounted in said housing for sensing the passage of the markings on the disc as the housing moves in relation to said disc and the disc maintains a position corresponding to the gravitational vector, said sensing means comprising first and second phototransistors spaced on or at an odd number of degrees of arc apart from each other to sense said spaces and said markings, and a third phototransistor positioned at a predetermined angular position from said first and second phototransistors for sensing gravitational alignment of the disc with reference to a zero degree reference marking on said disc wherein said first phototransistor is angularly positioned 91 degrees of arc from said second phototransistor and 90 degrees of arc from said third phototransistor; d. means for counting the number and determining the direction of movement of the markings as the markings move past said sensing means, and computing the angular position of the reference point relative to the gravitational vector; and e. display means for indicating the angular position of the reference point. - View Dependent Claims (9, 10, 11, 12, 13)
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Specification