Patent Application
20120266471
The present invention relates generally to the field of rulers and squares used for measuring, drawing, construction and the like, and in particular, to a new and useful combination ruler and square that can be configured as a 90 degree square or as a longer ruler for use, or into a shorter compact configuration for transportation and storage.
A large number of patents have sought to solve the problem of finding a way to make the large area occupied by a 90 square, smaller for storage and transport of this very useful but awkward to store and carry implement.
The usual solution suggested was been to place a hinge at the intersection of the two ruler members making up the square so that it can be folded into a more compact configuration. See for example U.S. Pat. Nos. 510,529 (1893); 551,839 (1895); 810,188 (1906); 844,420 (1907); 867,420 (1907); 1,021,850 (1912); 1,101,625 (1914); 1,209,855 (1915); 1,908,518 (1933); and 5,669,149 (1997).
U.S. Pat. No. 5,433,011 is also interesting for its showing of a multi-part level rather than a square, that can be elongated using mortis and tenon like joints.
Despite this long history of innovation in this rather simple art, a need still remains for an improved square that is easily and securely converted from its square, space using configuration, to a more convenient and practical configuration for storage and transport.
It is an object of the present invention to provide a combination ruler and square that has simple first and second elongated straight ruler members with first and second recesses in the upper surface near opposite ends of the first ruler member that receive a tongue extending from an end of the second ruler member to form first and second configurations of the combination that respectively create a square and an elongated ruler. Magnets and detents in the tongue and recesses retain the tongue in a respective recess in the first and second configurations and an extra pair of alignable magnets in the first and second ruler members cause the rule members to be attracted to each other in an aligned storage configuration of the combination where the second ruler member overlays the first ruler member.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
In the drawings:
Referring now to the drawings, in which like reference numerals are used to refer to the same or similar elements,
The combination includes a second elongated straight ruler member 32 having first and second opposite straight ends 34 and 36, opposite straight edges 38 and 40 extending between the opposite ends and upper and lower flat surfaces 42 and 44 between the ends and edges of the second ruler member. The first and second ruler members 12 and 32 have equal thicknesses between the upper and lower surfaces thereof and the first ruler member 12 has a first recess 52 in its upper surface 22 near its first end 14. The first recess 52 has a first flat bottom and a selected shape that is preferably but not necessarily a polygon, in particular a rectangle or square. Recess 52 has a depth from the upper surface 22 to its first flat bottom that is part, for example about ¼ to ⅔ of the total thickness of the first rule member 12, and preferably about ½ the total thickness so the overall strength of the first ruler member 12 is not overly compromised in this area of the first recess 52.
As best shown in
The second ruler member 32 has a tongue 72 extending from the first end 34 thereof, the tongue having substantially the same selected shape as the recess 52. Substantially the same selected shape means to convey that the tongue 72 and recess 52 are closely matched in perimeter shape and thickness with the tongue 72 being only slightly smaller in size so that the tongue 72 can be easily but closely fitted inside the recess 52 as shown in
To this end the tongue 72 has a thickness substantially equal to the depth of each of the recesses 52 and 62 so that the tongue closely fits into both of the first and second recesses in respective first and second configurations of the combination, the tongue having an upper surface that is coplanar with the upper surface 42 of the second ruler member 32 and the upper surface of the second ruler member 32 being coplanar with the upper surface of the first ruler member 12 in the first and second configurations of the combination. The tongue 72 has a width that is offset inwardly of both of the opposite straight edges 38 and 40 of the second ruler member 32, the tongue 72 having a lower surface 74 as seen in
In the first configuration of the combination as shown in
Tongue and groove sliding engagements between the side walls of the tongue 72 and the recesses 52 and 62 have been avoided since this would require a more accurate and time-consuming alignment of the tongue 72 with the recesses 52 or 62 then a sliding motion to engage them together. Instead, smooth vertical walls are used for the tongue 72 and for the recesses 52 and 62 as shown in the drawings to allow the tongue to be simply and approximately brought over the recess 52 or 62 and then moved slightly laterally until the tongue falls into the recess. This makes it easier to engage the tongue in either recess but does not sufficiently secure the two configurations against falling apart. To address this, the invention includes at least one magnet 87 in the tongue and at least one magnet 85, 86 in the first ruler member 12 in each of the first and second recesses 52, 62, that respectively align with and attract the magnet 87 in the tongue 72 in the respective first and second configurations 80 and 90 of the combination.
To mechanically keep the first and second rules together in each configuration, and therefore prevent them from sliding apart as the square or elongated ruler are being used, the invention also includes a first detent 83, 84 in the flat bottom of each of the recesses 52, 62, and a second detent 82 in the flat bottom of the tongue 72, that is shaped to engage with the first detect in the respective recesses in the first and second configurations of the combination for keeping the tongue from sliding out of the respective recess 52, 62.
In the embodiment shown the first detents 83 and 84 are female detents it the form of polygonal apertures in the flat bottom of each recess 52 and 62, that can receive the male polygonal projection 82 from the flat bottom 74 of the tongue 72 as shown in
The combination may also include an extra pair of alignable magnets 92 in ruler member 32 and 94 in ruler member 12 for causing the rule members to be attracted to each other in an aligned storage configuration shown in
To better engage the tongue to either recess and to better secured the storage configuration, rather than using only one magnet in each, a plurality of magnets in each of the tongue and recesses are provided, the plurality of magnets in the tongue aligning with and having complimenting polarities to (i.e. North facing South poles), the plurality of magnets in the recesses in the respective first, second and storage configurations of the combination. In the preferred embodiment, four magnets 85, 86 and 87 are at the corners of a square in recesses 52 and 62 and in the tongue 72. With all magnets 85, 86 and 87 having their North poles up, when in the first square-forming configuration 80 of
The ruler members 12 and 32 advantageously included graduated distant markings 102 and 104 on at least one of their upper and lower surfaces, along each of the opposite edges of each ruler member, the distance marking along one edge of each ruler member being English distance marking in inches and fractions therefore, and the distance marking along the opposite edge of each ruler member being metric distance marking in millimeters and centimeters for example.
In the embodiment of
In
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
