US2637110A

US2637110A - Drafting instrument

Info

Publication number: US2637110A
Application number: US169838A
Authority: US
Inventors: Harris S Gilbertson
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-06-23
Filing date: 1950-06-23
Publication date: 1953-05-05
Anticipated expiration: 1970-05-05

Description

y 5, 1953 H. s. GILBERTSON 2,637,110

' DRAFTING INSTRUMENT Filed June 23, 1950 H9- 2 Fig. 3

i A W \'\\.\I.\\\ I\\\\u\\\ vax Hamls 5. Gilber/san I N V EN TOR.

BY Mafia Patented May 5, 1953 UNITED STATES TENT OFFICE This invention relates to new and useful improvements in drafting instruments and the primary object of the present invention is to provide a combination ruler, square, protractor and compass.

Another important object of the present invention is to provide a drafting instrument in the form of a right triangle whose hypotenuse is provided with steps that are graduated in inches and fraction of inches along one edge of each step and the other edges of the steps being graduated in fractions of inches.

A further object of the present invention is to provide a drafting instrument in the form of a right triangle so that the centering point is at the point of intersection between the two sides and with a scale on the face of the instrument showing degrees of angle approximately 3-5-2- inches from the centering point so that the distance between each 5 will be 1% of an inch and with holes in the instrument between the 5 marks set at a secant to the circle of degrees to give strength to the material of which the instrument is made, such as plastic or other suitable transparent material.

A still further aim of the present invention is to provide a drafting instrument that is simple and practical in construction, small and compact in structure, and which is adaptable for use in tracing maps and designs, and by placing instrument on original and obtaining various points and transferring to copy, fairly accurate copies can be made.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a plan view of the present drafting instrument;

Figure 2 is an enlarged sectional view taken substantially on the plane of section line 2-2 of Figure 1; and

Figure 3 is an enlarged sectional view taken substantially on the plane of section line 3-3 of Figure 1.

Referring now to the drawings in detail, wherein for the purpose of illustration, there is disclosed a preferred embodiment of the present invention, the numeral it) represents a flat sheet of material, such as transparent plastic, in the shape of a right triangle having first and second straight side edges i2 and it that are disposed perpendicular to each other and which intersect at a centering point P.

1 Claim. (Cl. 33-404) The edges i2 and M are preferably six inches long and graduations G in inches and sixteenths of inches are provided on the sheet of material iii along the side edges I2 and it.

The hypotenuse of the right triangular sheet of material is provided with steps or identical isosceles triangles it, It, 26, 22, 2t and 26 whose bases are integrally formed with the hypotenuse of the right triangular sheet of material. Each of the isosceles triangles is provided with an edge that is disposed perpendicular to the side edge i2 and which is one inch long and graduated as at I, in sixteenths of an inch.

The other side edges of the isosceles triangles are also one inch long and are disposed perpendicular to the side edge Hi. The side edges of the triangles It, I8, 25), 22 and 2 1 that are disposed perpendicular to the side edge it are graduated into quarters of an inch, eighths of an inch, sixteenths of an inch, thirty-seconds of an inch and sixty-fourths of an inch respectively as shown in Figure 1.

Pencil receiving apertures 28 are provided in the sheet of material it. These apertures lie on an imaginary straight line that intersects the side edges i2 and it so that the angles included between the straight line and the edges I2 and M will be 45. The apertures 28 are spaced apart an eighth of an inch with graduations H on the sheet of material it disposed along the apertures 28.

Five arcuate lines are provided on the sheet of material it about the point P as a center. The arcuate lines are spaced equally apart and the outermost arcuate line is spaced approximately 3st: from the centering point P. Sets of radial lines L are provided on the sheet of material It and intersect the arcuate lines. There are five lines in each set of lines to represent 5 and the distance between each 5 will be of an inch. Each set of lines is provided with a pencil receiving aperture A on each arcuate line, there being five apertures A for each set of lines L or an aperture A for each degree with the degrees indicated in units of 5 as shown in Figure 1.

In view of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claim. Having described the invention, what is claimed as new is:

A drafting instrument comprising a flat sheet of material having first and second straight o edges disposed perpendicular to each other and a stepped edge whose risers are equal in length and which. risers. parallel the first edge of said sheet of material, each step of said stepped edge including two relatively perpendicular edges of equal length, scales on the sheet of material along each edge of each step, additional similar scales on the sheet of material along the first and second edges, the scales along one edge of each step being similar in unit to the units of the scales along the first and second. edges. and. the scales along the other edges of the. steps.

being increments different from each other and also different from the units along the first and second edges of the flat sheet of material.

HARRIS S. GILBERTS-ON;

References Cited in the file of this patent UNITED STATES PATENTS Number Number Name Date Wiley Oct. 14, 1947 Darling Oct. 18, 1887 Beckwith Aug. 14, 1888 Powell May 31, 1910 Cha'pin n Apr- 24, 1928 FOREIGN PATENTS Country Date Great Britain 1904 Switzerland Mar. 16, 1920 Switzerland Jan. 16, 1947 Great Britain Feb. 18, 1932