US3020642A

US3020642A - Drafting instrument

Info

Publication number: US3020642A
Application number: US859205A
Authority: US
Inventors: Irvin J Rickey
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-12-14
Filing date: 1959-12-14
Publication date: 1962-02-13
Anticipated expiration: 1979-02-13

Description

l. J. RICKEY DRAFTING INSTRUMENT Filed Dec.

Feb. 13, 1962 me 'RV'N J ATTORNEY FIG.7

nite States @a 3,920,642 Patented Feb. 13, 1962 aina-.ce

3,620,642 DRAFIING INSTRUMENT Irvin J. Rickey, 1013 SW. 30th, Oklahoma City, Okla. Filed Dee. 14, 1959, Ser. No. 859,205 4 Claims. (Cl. 33-93) The present invention relates to drawing tools and more particularly to a drafting instrument.

In structural drawing, it is frequently necessary to draw numerous parallel lines at selected angular positions with respect to a base line or reference position as well as a plurality of arcs to different radii, as for example, when detailing beams and channel members on the structural drawing.

It is, therefore, the principal object of the instant invention to provide a draftsmans triangle with an adjustable swinging arm or blade which may be selectively positioned at any angle and pivoted about its connection with the triangle.

Another object is to provide a conventional drafting triangle with a sliding bar which may be adjustably positioned along one side of the triangle and to which the swinging blade is pivotally connected.

A further object is to provide a sliding bar means having a swinging blade pivotally connected thereto wherein the bar may be removably connected to opposing side portions of a drafting triangle.

Another object is to provide a device of this class wherein the swinging blade is provided with a series of progressively spaced-apart apertures throughout its length, for forming a like series of arcs originating at the pivotal connection of the arm.

A further object is to provide a preferably transparent drafting instrument which will perform a lwide variety of functions in drafting work, such as drawing parallel lines, radii to a common or different centers, and arcs from a common or a plurality of centers.

Still another object is to provide a drafting instrument which will not impair the use of the conventional triangle, forming a part of the combination, when used separately.

The present invention accomplishes these and other objects by providing a drafting triangle and forming an elongated slot in spaced parallel relation with respect to the hypotenuse side edge of the triangle. Sliding bar means is connected to one surface of the triangle through the slot and extends outwardly of the hypotenuse edge in right angular relation thereto. An elongated substantially rectangular arm or blade is pivotally connected at one end to the free end of the bar. Intermediate its ends, the bar is provided with guide means and an upstanding wall for contacting the adjacent edge or edges of the triangle and iixing the position of the bar relative to the triangle. y

Other objects will be apparent from the following description when taken in conjunction with the accompanying single sheet of drawings, wherein:

FIGURE 1 is a plan view of the device illustrating, by dotted lines, various positions of the bar and swinging blade;

FIGURE 2 is a vertical cross-sectional view taken substantially along the line 2--2 of FIG. l;

FIGURE 3 is a fragmentary plan view of an alternate position of the bar;

FIGURE 4 is a plan view of the swinging blade, per se, illustrating a series of longitudinally spaced-apart apertures therethrough;

FIGURE 5 is a view, similar to FIG. 4, illustrating an alternate arrangement or spacing of the series of apertures; and,

FIGURES 6 and 7 are vertical cross-sectional views taken substantially along the lines 6-5 and 7--7 of FIG. 5, respectively.

Like characters of reference designate like parts in those figures of the drawings in which they occur.

In the drawings:

The reference numeral 1t) indicates the device, as a whole, which includes a conventional transparent triangle l2 having a pair of

arms

14 and 16 integrally joined to form a right angular corner portion 18, and a third arm 20, opposite the right angular corner, integrally joined to the

arms

14 and 16 and forming the hypotenuse of the triangle. The triangle i2 is illustrated as a 45 triangle but which may be a 60-90 triangle or of other triangular shapes, if desired, but preferably having at least one corner. An elongated relatively narrow slot 22 is formed through the arm 20 in spaced parallel relation with respect to the hypotenuse edge 24 of the triangle. The undersurface 26 of the triangle is recessed on opposing sides of the slot, as at 23, for recessing the head portion 30 of a bolt 32 extending transversely of the triangle through the slot 22.

A flat substantially rectangular bar 34 is flatly positioned upon the upper surface of the triangle and is provided with an aperture 36, adjacent one end, for receiving the upwardly disposed end of the bolt 32 to which a knurled nut 38 is threadedly connected. A washer 40 is interposed between the nut 38 and the upper surface 42 of the bar 34 so that the nut 38 may be easily loosened or tightened for slidably positioning the bar at selected positions along the slot 22. A guide member 44, integral vvith the bar, extends transversely of the bar in depending relation and has one Side edge 46 in contiguous contact with the hypotenuse edge 24 for maintaining the bar 34 perpendicular with respect to the hypotenuse of the triangle. The free end of the bar projects beyond the hypotenuse edge 24 a selected distance and is formed semi-circular, as at 48, and is provided with -a central vertical opening 5t). One surface of the arcuate end of the bar is marked or scored with radial lines 49, spaced 15 apart, indicating degrees for the purpose more fully explained hereinbelow.

An elongated substantially rectangular arm or blade 52, substantially equal in thickness to the thickness of the triangle l2, is provided with a transparent stud bolt 54 adjacent one of its ends. The bolt 54 is iixed at one end within the blade and projects outwardly of the opposing surface a selected distance. The bolt 54 is closely received by the opening 50 and is held therein -by a knurled nut 56. The end portion of the blade 52, adjacent the bolt 54, is arcuately curved to describe a semicircular end 58 for cooperation with the semi-circular end 48 of the bar. One surface, preferably the lower surface, of the blade is centrally scribed or scored longitudinally, as at 60, and a second transverse score line or mark '62 intersects the mark 6i? at the center of the bolt 54. This permits manually loosening the nut 56 and alignedly positioning the

lines

60 and 62 with selected ones of the degree marks 49 on the semi-circular end 48 of the bar. Throughout its length the blade 52 is provided with a series of apertures 64 which are progressively spaced outward from the center of the bolt 54 beginning at a distance of approximately 2 inches therefrom and being longitudinally spaced-apart in increments of a 1/16 of an inch and terminating 8 inches from the bolt. The apertures at one side ofthe longitudinal center line of the blade are spaced apart l/lf; of an inch while those on the opposing side of the center line read or are spaced at 1/8 inch intervals. Obviously the inch or fractions thereof may be marked on the blade. As shown in FIG. 2 the blade lies in the plane of the triangle.

FIG. 5 illustrates an alternate manner of arranging the spacing and positioning of the apertures as indicated at 64A. Obviously these

apertures

64 and 64A may be arranged in any desired pattern and spacing for achieving the desired arcs of different radii to be drawn by the blade. Each of the apertures are formed, as shown in FIG. 7, wherein each aperture has walls 65 converging downwardly terminating in a relatively small cylindrical end portion 66 opening to the underside of the blade and of a size for closely nesting the lead of a pencil or the like.

The upper surface of the bar 34 is provided with an opstanding wall 70 defining a right angular corner 72. The height of the wall is substantially equal to the thickness of the triangle, as may be seen in FIG. 2. The blade 52 may be disconnected from the bar 34 and the bar may be disconnected from the hypotenuse side of the triangle and inverted and connected to the right angular corner of the triangle through a suitable aperture 71 by the bolt 32 and nut 38. The inwardly disposed surface of the wall 70 cooperatively contacts the outwardly disposed edges of the

arms

14 and 16, adjacent their juncture, thus firmly securing the bar 34 to the triangle (FIG. 3). The blade 52 is then similarly connected to the downwardly disposed surface of the free end 4S of the bar. This places the blade 52 in the plane of the triangle. Selected side edges of the triangle may be scored or marked with increments of the measurement as at 7S.

Operation ln operation, a selected side edge of the

triangle arm

14 or 16 is placed in contiguous contact with the edge of a parallel rule or T-square and with the bar connected to the slot 22 the blade 52 is secured in a selected angular position. A line may then be drawn with one side of the blade as a guide and other lines parallel to this line may then be drawn by simply manually sliding the bar along the hypotenuse side of the triangle in the preferred direction. Similarly the bar may `be selectively positioned on the triangle and the nut 56 loosened whereby a pencil or the like may be inserted into the

selected apertures

64 or 64A for drawing a plurality of arcs from a common center. As shown in FIG. l, with the bar connected to the hypotenuse side of the triangle, the blade 52 may be pivoted through an angular range of 180.

Operation of the device when the bar 34 is connected to the right angular corner of the triangle is similar to the above description except, that, obviously the hypotenuse edge 24 forms the base line. In this arrangement, as shown by the dotted lines in FIG. l, the blade 52 may be pivoted through a range of 276.

Obviously the invention is susceptible to some change or alteration without defeating its practicability, and l therefore do not wish to be confined to the preferred embodiment shown in the drawings and described herein, further than I am limited by the scope of the appended ciaims.

I claim:

l. A drafting instrument, comprising: a draftsmans triangle having sides defining a right angle corner, said triangle having an aperture adjacent said right angular corner; a relatively short substantially rectangular bar fiatly connected by one end portion to the upwardly disposed surface of said triangle through the aperture therein, the free end portion of said bar projecting beyond said right angular corner; an outstanding wail carried intermediate its ends by said bar forming a right angular corner in contiguous contact with the end portions of the sides of said triangle forming the right angular corner for preventing lateral movement of said bar relative to said triangle, the free end portion of said bar having a semi-circular edge and having a central aperture coaxial with the semi-circular edge, at least one surface of the semi-circular edge of said bar being scored to indicate radial measurements; an elongated blade pivotally connected at one end to the free end portion of said bar, said blade having parallel opposing side edges and having at least one surface of its pivotally connected end provided with at least one score for co-operative registration with the radial scores in said one surface of said bar for fixing said blade at predetermined angular positions relative to said triangle and said bar; and means for releasably securing said blade in such positions.

2. A drafting instrument, comprising: a draftsmans triangle having a pair of arms integrally joined to form a right angular corner and having a third arm integral with the end of said pair of arms forming a hypotenuse side edge, said triangle having a transverse aperture adjacent the right angular corner equally spaced between the side edges forming said right angular corner; a substantially rectangular` flat bar overlying the right angle corner and removably connected atly by one end portion to the adjacent surface of said triangle through the aperture therein, the free end portion of said bar projecting beyond said right angular corner in perpendicular relation with respect to said hypotenusc edge, said bar having a semi-circular free end edge and having an aperture coaxial with the semi-circular edge, at least one surface of the semi-circular edge of said bar having a series of radially scored indicia; an outwardly projecting wall formed intermediate the ends of said bar on that side surface in contact with said triangle, said outstanding wall forming a right angular corner in contiguous contact with the side edges of said triangle `forming said right angular corner; an elongated blade pivotally connected at one end to the free end portion of said bar, said blade having parallel opposing side edges and having at least one surface of its pivotally connected end provided with at least one score for co-operative registration with the radial scores in said one surface of said bar for fixing said blade at predetermined angular positions relative to said triangle and said bar; and means for releasably securing said blade in such positions.

3. A drafting instrument, comprising: a draftsmans triangle having a pair of arms defining a right angular corner and having a third arm forming a hypotenuse edge of said triangle, said triangle having a transverse aperture adjacent the right angular corner equally spaced between the said edges forming said right angular corner; a substantially rectangular fiat bar overlying said triangle and removably connected flatly by one end portion to one surface of said triangle through the aperture therein, the free end portion of said bar projecting beyond said right angular corner in perpendicular relation with respect to said hypotenuse edge, said bar having a centrally bored semi-circular free end portion, at least one surface of the semi-circular edge having a series of radially positioned scores; a wall connected to said bar intermediate its ends to define a right angular recess in contiguous contact with the right angular corner of said triangle, the height of said wall being substantially equal to the thickness of said triangle; an elongated blade pivotally connected at one end to the free end portion of said bar, said blade having parallel opposing side edges and having at least one surface of its pivotally connected end provided with at least one score for co-operative registration with the radial scores in said one surface of said bar for fixing said blade at predetermined angular positions relative to said triangle and said bar; and means for releasably securing said blade in such positions.

4. A drafting instrument, comprising: a draftsmans triangle having a pair of arms defining a right angular corner and having a third arm forming a hypotenuse edge of said triangle, said triangle having a transverse aperture adjacent the right angular corner equally spaced between the said edges forming said right angular corner; a substantially rectangular dat bar overlying said triangle and removably connected flatly by one end portion to one surface of said triangle through the aperture therein, the free end portion of said bar projecting beyond said right angular corner in perpendicular relation with respect to said hypotenuse edge, said bar having a centrally bored semi-circular free end portion, at least one surface of the semi-circular edge having a series of radially positioned scores; an outstanding wall connected to said bar intermediate its ends to dene a right angular recess in the plane of said triangle wit-h one surface of said wall contiguously contacting the edges of the arms forming the right angular corner of said triangle, the height of said wall being substantially equal to the thickness of said triangle; an elongated blade pivotally connected at one end to the free end portion of said bar, said blade lying in the plane of said triangle and being substantially equal with respect to the thickness of said triangle, said blade having parallel opposing side edges and having at least one surface of its pivotally connected end provided with 15 218931126 at least one score for co-operative registration with the radial scores in said one surface of said bar for xing said blade at predetermined angular positions relative to said triangle and said bar; and means for releasably securing said blade in such positions.

References Cited in the ile of this patent UNITED STATES PATENTS 738,130 Waymire Sept. 1, 1903 765,300 Williams July 19, 1904 1,142,368 Row June 8, 1915 1,336,241 La May Apr. 6, 1920 Coallier July 7, 1959