Electronic level displaying inclination with regard to instrumen

Details Electronic level displaying inclination with regard to instrumen Electronic level displaying inclination with regard to instrumen

1995-02-13

1997-01-14

Fulton, Christopher W.

Geometrical instruments

Indicator of direction of force traversing natural media

Level or plumb, terrestrial gravitation responsive

33343, 73 1E, 340689, G01C 906, G01C 918

Patent

active

055927459

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

1. Field of the Invention
This invention relates to an electronic level and specifically to the visual display and calibration of the level.
2. Description of the Prior Art
Electronic levels known in the art include that sold by Wedge Innovations Inc. and as disclosed in U.S. Pat. No. 4,912,662 issued Mar. 27, 1990 to Butler et al. (assigned to Wedge Innovations Inc.). Furthermore, such prior art electronic level displays show the inclination in degrees or percent slope, which are typically not the inclination measurements used by building tradesmen (carpenters, masons etc.).
Butler et al. also disclose at col. 9, lines 6-11: routine of block 146 and the display routine of block 148. The display function is calculated at twelve times the tangent of the angle determined by block 146. This gives the rise to run value of inches per foot.
Prior art devices thus often do not provide a satisfactory indication of how far from level or plumb one is in a mode useful to tradesmen who tend not to think in terms of inches per foot or percent slope or angular slope.


SUMMARY OF THE INVENTION

In accordance with the invention, an electronic level has a visual display that displays rise over run (deviation from a null) in terms of deviation from the null (level or plumb) in inches per the actual length of the level instrument (such as two or four feet). This advantageously corresponds to the way that such levels are used by tradesmen. It has been found that building tradesmen typically prefer either variable user offsets for transferring of arbitrary angles, or a series of fixed offsets such as 1/2 inch, 1 inch or 2 inches per linear two feet or 1 or 2 or 4 inches per linear four feet, which is readily converted to a deviation from a null (offset) per standard dimensions such as a ceiling height, door height, etc.
The visual display includes a number of parallel line segments resembling a typical ruler scale. When the device is at a null (level or plumb or at some other preselected inclination), only the central line segment is illuminated. When the device is inclined at an angle from the null, one or more of the line segments are illuminated starting from the center line segment. The more line segments that are illuminated starting from the center line segment, the greater the amount of inclination indicated. Each line segment in one embodiment indicates 1/64th inch of additional inclination per horizontal foot. The line segments on either side of the central line segment thus provide an indication of inclination in either direction, i.e. that the left end or right end of the device is inclined. Additionally, numerals are provided associated with the scale to show the amount of inclination per arbitrary length (such as two feet or four feet) related to the instrument length. Also included is a slope indicator and a numerical indicator for indicating the fixed offset mode. In fixed offset mode the null indication is provided not at level or plumb relative to the plane of gravity, but instead at some fixed angle thereto. Typically this would be for instance 1/2 or 1 or 2 inches per two feet or 1 or 2 or 4 inches per four feet which are measurements typically used in construction or readily converted thereto.
Levels utilizing bubble vials, also called carpenter's or mason's levels, have been in existence for many years. It is well known that to check the accuracy of these devices, the level is placed on a moderately level surface and the position of the bubble within the vial noted. The level is then rotated 180.degree. in a horizontal plane and the bubble position again noted. If the level is accurate, the bubble displacement will be equal in both of the tested positions with reference to the pair of parallel lines inscribed on the bubble vial, thus showing that the reference lines are midway or the average of the two readings.
This concept can be extended to electronic levels. Butler et al. describes a calibration routine wherein electronically measured results are averaged in each of two 18

REFERENCES:
patent: 3233235 (1966-02-01), Wright
patent: 3861052 (1975-01-01), Siegfried
patent: 4551921 (1985-11-01), Puyo et al.
patent: 4606133 (1986-08-01), Mills
patent: 4641434 (1987-02-01), Engler
patent: 4716534 (1987-12-01), Baucom et al.
patent: 4912662 (1990-03-01), Butler et al.
patent: 4932132 (1990-06-01), Baker et al.
patent: 5031329 (1991-07-01), Smallidge
patent: 5136784 (1992-08-01), Marantz
patent: 5313713 (1994-05-01), Heger et al.

Affiliated with

Also associated with

Rating

Electronic level displaying inclination with regard to instrumen does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Electronic level displaying inclination with regard to instrumen, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic level displaying inclination with regard to instrumen will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1380496