Multiple angle compact spirit level

The level with a generally u-shaped or round, rigid frame. The outer surface is comprised of a number of planar reference faces that are at different fixed angles to a spirit vial mounted in the frame. Optionally, magnets are embedded in the reference faces. Optionally, there are grooves in the reference faces.

CROSS-REFERENCES TO RELATED APPLICATIONS

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REFERENCE TO A SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX

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BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to measuring devices, more particularly, to spirit levels for determining if a work piece is at the desired angle.

2. Description of the Related Art

Spirit levels are old and well-known and enjoy wide usage. In general, a spirit level comprises an elongated frame with at least one flat reference surface and at least one spirit vial mounted in the frame. The vial contains a liquid with an entrapped bubble. The reference surface is placed against a workpiece and, when the bubble is centered between a pair of markings on the vial, that is, the vial is horizontal, that workpiece is known to be at a predetermined angle. Many spirit levels are provided with two or more vials at different fixed angles so that they can be used to check more than one surface angle. Naturally, as more vials are added, the level becomes more elongated and less portable.

One solution to the increased size of the multiple-angle spirit level, disclosed in U.S. Pat. No. 2,568,143, is the use of a single vial that has multiple surfaces for centering the bubble at different angles to a single reference surface. Another solution, disclosed in U.S. Pat. No. 5,127,16, uses a single vial with changeable end caps. The relative size of the two end caps determine the angle to be checked. Another solution, disclosed in numerous patents, is the adjustable level where the vial is mounted so that it can be rotated relative to the reference surface. The rotatable vial has an angular scale so that the angle of the vial to the reference surface can be set as desired.

BRIEF SUMMARY OF THE INVENTION

An object of the present invention is to provide a level that can indicate multiple angles with a single spirit vial.

Another object is to provide a compact level that can indicate multiple angles.

The level of the present invention has a generally u-shaped or round, rigid frame with the outer surface comprised of a number of reference faces that are at different angles to a spirit vial. The spirit vial is of a type that is well-known in the art. The vial is securely mounted to an inner portion of the frame.

A reference face has a planar surface that is at a known angle to the vial axis. The reference faces are generally contiguous and are typically at standard angles to the vial, including 0°, 22.5°, 30°, 45°, 60°, and 90°, although they can be at any known angles desired.

The outer surface may have features other than reference faces, such as a carrying hook or handle, or a flange for a carrying cord.

Optionally, magnet are embedded in the reference faces to provides a means to attach the level to ferrous surfaces without having to manually hold it in place.

Optionally, there are grooves in the reference faces that extend parallel to the side walls to help hold the level stable against a cylindrical surface.

Other objects of the present invention will become apparent in light of the following drawings and detailed description of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The level10,110,210of the present invention, shown in several embodiments inFIGS. 1-3, are comprised of a frame12,112,212and a spirit vial14,114,214. In short, the level10,110has a number of references faces30a-30f,130a-130f,230a-230l(collectively,30,130,230) that are at different angles to the vial14,114,214so that the level10,110,210can be used to measure different angles while remaining compact.

In one embodiment of the level10of the present invention, the frame12is generally U-shaped, as shown inFIGS. 1,4, and5. It has an outer surface20, an inner surface22, a pair of top surfaces24, and a pair of opposed side walls26. The outer surface20is composed of a contiguous set of reference faces30, described below. The inner surface22generally concentric with the outer surface20, and has a pair of opposed walls32and a floor34. The top reference surfaces30hare coplanar and the side walls26are generally parallel. The thickness of the frame12, that is, the dimension separating the side walls26, is large enough so that the level10rests stably on the outside surface20. The thickness is dependent upon the overall size of the level10, that is, the larger the level10is, the thicker the frame12needs to be in order to be stable.

In another embodiment of the level110of the present invention, shown inFIG. 2, the frame112is generally U-shaped, like the embodiment ofFIG. 1, but without the inner surface22of the embodiment ofFIG. 1. It has an outer surface120, a top surface124, and a pair of opposed side walls126. The outer surface120is composed of a contiguous set of reference faces130, described below. The side walls126are generally parallel. As with the first embodiment, the thickness of the frame112is large enough so that the level110rests stably on the outside surface120.

In another embodiment of the level210of the present invention, shown inFIG. 3, the frame212is generally circular. It has an outer surface220, an inner surface222, and a pair of opposed side walls226. The outer surface220is composed of a contiguous set of reference faces230, described below. The inner surface222has a pair of opposed walls232, a floor234, a ceiling236. The side walls226are generally parallel. Like the embodiments ofFIGS. 1 and 2, the thickness of the frame212is large enough so that the level210rests stably on the outside surface220.

The U-shaped and circular embodiments described above are but two examples of the arc through which the frame12can extend. The present invention contemplates that the arc can extend through any arc, as long as it is able to hold a vial14and have multiple reference faces. For example, a frame with an arc of 90° can hold a vial and have references faces of 0°, 90°, and an angle between 0° and 90°.

In the present specification, except where specifically indicated, all references to elements of the U-shaped embodiment10ofFIG. 1are intended to be references to the other embodiments as well.

The frame12is composed of a rigid, stable material. Examples of contemplated materials include plastics, fiberglass, carbon composites, and metals, such as aluminum alloys, steel, and titanium alloys.

The spirit vial14,114,214is of a type that is well-known in the art. As shown inFIG. 4, a sealed, transparent, slightly convex tube40contains a liquid with a bubble42. A pair of annular rings44that are slightly more than the length of the bubble42apart delimit the center of the vial14. When the vial axis46is horizontal, the bubble42is centered between the rings44.

In the embodiments ofFIGS. 1 and 3and as shown inFIG. 4, the vial14is securely mounted between the two opposed inner walls32of the frame12. Typically, a pair of coaxial holes are formed in the frame12, the vial14is positioned centrally in the holes, and an adhesive secures the vial14in the holes. The present invention contemplates that any method that can adequately secure the vial14in the appropriate position can be used.

In the embodiment ofFIG. 2, the vial114is securely mounted parallel to the top surface124in a depression148in the top surface124. Typically, an adhesive secures the vial114in the depression148. The present invention contemplates that any method that can adequately secure the vial114parallel to the top surface124can be used.

The present invention also contemplates that there may be more than one vial14. There may be two or more vials14mounted in the frame12at different angles.

The outer surface20of the frame12includes a plurality of reference faces30. A reference face30has a planar surface that is at a known angle to the vial axis46. In the configuration ofFIG. 4, reference face30ais at angle Θa=90° (perpendicular) to the vial axis46, reference face30bis at angle Θb=45° to the vial axis46, reference face30cis at angle Θc=22.5° to the vial axis46, reference face30dis parallel (0°) to the vial axis46, reference face30eis at angle Θe=30° to the vial axis46, reference face30fis at angle Θf=60° to the vial axis46, reference face30gis at angle Θf=90°, and reference face30h, which is the two coplanar surfaces at the top of the frame12, is parallel (0°) to the vial axis46. In the configuration ofFIG. 5, reference face30tis at angle Θa=90° (perpendicular) to the vial axis46, reference face30uis at angle Θu=45° to the vial axis46, reference face30vis at angle Θv=22.5° to the vial axis46, reference face30wis at angle Θw=30° to the vial axis46, reference face30xis at angle Θx=60° to the vial axis46, reference face30yis at angle Θy=90° (perpendicular) to the vial axis46, and reference face30z, which is the two coplanar surfaces at the top of the frame12, is parallel (0°) to the vial axis46.

These examples are but two sets of reference face angles. The present invention contemplates that the reference faces30can be at any desired angle to the vial axis46and that there may be any number of reference faces30.

In the embodiment ofFIG. 3, where the outer surface220extends completely around the level, there can be more reference faces230or more duplicate reference faces230. An example configuration is shown inFIG. 6, reference face230sis at angle Θs=90° (perpendicular) to the vial axis246, reference face230tis at angle Θt=22.5° to the vial axis246, reference face230uis parallel (0°) to the vial axis246, reference face230vis at angle Θv=30° to the vial axis246, reference face230wis at angle Θw=90° (perpendicular) to the vial axis246, reference face230xis at angle Θx=60° to the vial axis246, reference face230yis parallel (0°) to the vial axis246, and reference face230zis at angle Θz=45° to the vial axis246. As with the other embodiments, the present invention contemplates that the reference faces230can be at any desired angle to the vial axis246and that there may be any number of reference faces230.

The present invention also contemplates that the outer surface20may not be composed entirely of reference faces30, but may include other features that are not reference faces. In the example ofFIG. 7, one section of the outer surface120has a flange138for carrying. Other contemplated features include carrying hooks or handles.

Optionally, as shown inFIGS. 8 and 10, a magnet60is embedded in one or more of the reference faces30. The magnet60provides a means to removably attach the level10to ferrous surfaces without having to manually hold it in place. This is particularly useful for non-horizontal surfaces.

Optionally, as shown inFIGS. 9-11, there is a groove62in one or more of the reference faces30that extends parallel to the side walls26. The purpose of the groove62is to help hold the level10stable against a cylindrical surface, such as a water pipe or electrical conduit. As shown inFIGS. 10 and 12, the groove62is generally V-shaped, with side walls64that slope inwardly. The side walls come together at an inside corner68that is parallel to the plane of the reference face30so that the groove62is at the same angle to the vial axis as the reference face30. The corners66,68are typically rounded. In the configuration ofFIG. 10, the groove62extends through the face of an embedded magnet60. In the configuration ofFIG. 12, each face64of the groove62has an embedded magnet60.

As indicated above, one object of the present invention is to provide a multiple angle spirit level that is compact. Compact means that the level is portable and can be carried easily. For example, in one configuration of the U-shaped embodiment ofFIG. 1, the level10is 2.5 inches high, 2 inches wide, and 0.75 inches thick. This size permits a person to carry the level in the pouch at the belt or in a small tool box.

Thus it has been shown and described a multiple-angle spirit level which satisfies the objects set forth above.

Since certain changes may be made in the present disclosure without departing from the scope of the present invention, it is intended that all matter described in the foregoing specification and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.