US2322002A - Drafting pen - Google Patents

Description

June 15, 1943. F. G. EUANKs DHAFTING PEN Filed Feb. 1a', 1942 Gtorneg Patented June 15, 1943 DRAFTING PEN Floyd G. Eubanks, Pasadena, Calif., assigner, by y'direct and rnesne assignments, of thirty-one and onehalf per cent to Francis E. Vaughan,

Pasadena, live per cent to Robert M.'

McManigal, South Pasadena, Calif., six per cent to Edward Floyd Eubanks, six per cent to Philip Robert Eubanks, six per cent to Patricia Rose Eubanks, eight per cent to Edward Urner Vaughan, and eight per cent to Philip Alfred Vaughan, all of Pasadena,Calif.

Application February 18, 1942, Serial No. 431,387

(Cl. 1Z0-109.5)

4 Claims.

My 'invention relates to new and useful improvements in drafting pens. For the purpose ofV illustration, I disclose a drafting pen comprising blades; said blades being provided with means for controlling their separation.

The object of my invention is to provide a drafting pen with blades which can easily be con* struc-ted of high quality material.

Another object of my invention is to so con struct the blades of the pen that they can be widely separated to facilitate the cleaning of their points or nibs. i

Another object of my invention is to provide a pen for a compass, said pen having means for locking it in a position normal to the drawing surface.

My invention has other objects which will be evident from a study of the following specification read in connection with the accompanying drawing.

Referring to the drawing:

Figure l is a front View of a ruling pen embody-` ing the features of my invention.

Figure 2 is a section taken on the line 2 2 of Figure l.

Figure 3 is a section taken on the line 3-3 of Figure 2.

Figure 4 shows another embodiment of my invention in which the pen is attached to a compass.

Figure 5 is an enlarged fragmentary section showing the details of construction of the pen shown in Figure 4.

Figure 6 is a section taken on the line 6--6 of Figure 5.

Referring to Figures 1, 2 and 3, the numeral i l indicates a spool having flanges I2, and about which is looped the vsheet steel strip I3. The sheet steel strip I3 can readily be punched from sheet steel stock and then formed in a die to the desired shape. The 4ends of the metal strip I3 are ground to form the nibs I4 and I5. rThe thumb screw with thumb piece I6 and screw I'I controls the separation of the nibs lll and I5. The screw I'I passes through a clearance hole in the blade I8 and is screwed through the blade I9. A small bushing 2li is electrically welded into the blade I9 to afford additional thickness in order to engage passing through the spool II and through a hole in the metal strip I3, is screwed into the pen support 22, thus firmly holding the pen to the support. Since the screw 2| passes through both the spool I I and the metal strip I3, it effectively prethe threads on the screw -I'I. The screw 2l.'

vents said metal strip I3 from slipping about said spool II. The pen support 22 may be presstted securely into the handle 23 which can b'e of metal, plastic, fiber, wood, or other suitable material.

The metal strip 53 is formed in such amanner that the spring pressure tends to separate the nibs Id and l. The thumb screw i6, Il, holds the nibs I, l5, close together as desired, the proximity ol the nibs to each other controlling the breadth of the line being ruled by the pen.

Although the blades may be formed of any suitable metal strip, I prefer to use sheet spring steel of high quality and thereby provide a pen of excellent performance and durability. The blades are adapted to be widely separated, as clearly shown in Figure 2 of the drawing.

Figures 4, 5 and 6 show a modification of my invention adapted to be used on a compass. In this modification the sheet steel strip comprising the blades is adjustably mounted on the spool so that the pen can be set in a position normal to the drawing surface and a locking means is provided to hold the blades in any adjusted position.

As an instance of this arrangement, the parts 2 and 23 are limbs of a compass to which, respectively, extension point 29 and pen 30 are adapted to be attached. The numeral 3| indicates a spool with anges 32, about which is looped a sheet steel strip 33. The upper part of a supporting rod 34 is clamped in the compass limb 28 in the same manner as a pencil lead is held. The lower part of the supporting rod 34 is threaded and passes through a hole 35 in the steel strip 33 and through a hole in the spool 3I, being firmly held in the latter by means of a set screw 36. A thumb screw 31 is screwed upon the threaded portion of the supporting rod 34. Below this thumb screw 3'! is a curved lock plate 38, through which also passes the supporting rod 34.

When the thumb screw 31 is loose above the lock plate 38, the sheet steel strip 33 is released and, since the hole 35 is elongated somewhat about the periphery of the spool, the sheet steel strip can be slipped about the spool through a small arc and thus adjusted so that the axis of the pen is perpendicular to the drawing surface. When the thumb screw 31 is screwed downward it presses upon the lock plate 38 and thus firmly holds the steel strip 33 in the position to which it is adjusted in order to be perpendicular to the drawing surface as the compass legs 2'I and 28 are closed or spread to describe small or large circles. The method by which the pen can be adjusted perpendicularly to the drawing surface is shown in Figure 5, in which the position of the supporting rod 34 is shown in dotted lines as the instrument is used in describing large circles.

The nibs 40 and 4l should be set perpendicular to the line determined by the tip of the extension point 29 and the point of the pen so that the pen Will draw tangentially. In order to make this adjustment the set screw 36 can be released and the spool rotated axially about the supporting rod 34 and into the proper position. The set screw 36 is then tightened.

Figure 6 shows how the compass pen can be adjusted to follow in the direction of the desired circle.

Other advantages and the use and operation of the drafting pen of my invention will be readily understood by those skilled in the art to which the invention appertains. While I have described the form of my invention which I now `ends to provide the nibs of said pen, a handle,

said strip and said cylindrical member being held together and to the pen handle by means of a screw passed through them and threaded into said handle.

fil

2. A pen for drafting compasses comprising a strip of sheet metal looped at its mid-portion about a cylindrical member and tapered at its ends to provide nibs, a support extending from said cylindrical member through an opening in the looped mid-portion of said strip, said strip being adjustable about the axis oi said cylindrical member, and means on said support for locking said strip against movement about said cylindrical member.

3. A drafting pen comprising a strip of sheet metal tapered at its ends to provide nibs and being of substantially uniform thickness throughout theremainder of its length, a cylindrical spool having peripheral flanges at its ends, said strip having its mid-portion looped'about said spool between said flanges, adjustable means intermediate said spool and said nibs for controlling the spacing of said nibs, a handle, and means for retaining said spool within the loop of said strip and securing said strip to said handle.

4. A drafting pen comprising a strip of sheet metal looped at its mid-portion about a cylindrical member and tapered at its ends to provide nibs, said strip being of substantially uniform thickness throughout the remainder of its length, and a handle including fastening means extending through an opening in the looped midportion of said strip and into said cylindrical member.

FLOYD G. EUBANKS.

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