US2219766A - Drafting equipment - Google Patents

Description

Oct. 29, 1940. F. w. COTTERMAN 2,219,766

DRAF'TING EQUIPMENT Filed Jan 11, 1939 3 Sheets-Sheet l 0611. 29, 1940. F, w COTTERMAN 2,219,766 DRAFTING EQUIPMENT Filed Jan. 11, 1959 s Sheets-Shet 2 w V .J/ n A 3 w/ 01 'i a i I a 6 044 i ung" III! zz "i 51 ii" 15. p I I. ,1... III- ",1": 1 4... 111i 1 4 M n M 06. 29. 1 0- F. w. COTTERMAN 7 DRAFTING EQUIPMENT Filed Jan. 11, 1939 s sheets-sheet 3 IIIIIIII/l Patented Oct. 29, 1940 V a I T 1 i i UNITE-D STATES PATENT 'OFFlCEi DRAFTING EQUIPMENT 7 Frederick W. Cotterman, Dayton, "Ohio, assignor of one-half toBessie D Apple, Dayton, Ohio I Application January-11, 1939. Serial No. 250,323

I '7 Claims. (01. 3342; This invention relates to drafting equipment 8 is asection thruthe guideibar taken at and particularly to drawing boards, angles, etc. 8 8 of I v g An object of the invention is'to'provide a FigpQshoWslines whichmaybe made with the drawing board having permanent clamping toolFig. Eat a single setting.

= means for securing the drawing paper tothe Fig. ld'shows'afplurality of lines which maybe 5" board whereby thumb tacks, adhesive tape and made with'thefangle'shown on the 'boardin'Fig. 2 similar fastening means are unnecessary. *Similar'nume'rals refer to similar parts thruout Another object is toso construct the clamping the severalviews. means that holds the paper to the board that Therearea number of classes of drafting in 10' there will be no part extending above the top which a uniform size of sheetfisused. 1 One of the ll) surface of the paper, to-the end that angles and most importantofthese is the making-:of Patent similar tools may be moved over the entire work- Oflice drawings. The equipment *herein shown ing surface of the paper without encountering has particular advantages when :used' for this any obstruction. purpose.

Another object is to provide fixed means on The stand .20fsfofconventional design compris 155 the board and on the angle, which cooperate to ing a pedestallthaving legs '24, a rod 26 vertiguide the angle in the same manner as it may cally 'slidable in the pedestal 'and ahand'screw 28 ordinarily be guided by a T square, to the end for maintainingthe vertical position ofthe rod; that the T square maybe eliminated. The drawingboard "30 may bescnred to the Another object is to provide adjustable means stand injanyconvenient manner'asiby'screws 3 2, 20 cooperating with fixed means on the board for Fig. 3, extendingthru'a spider 34 into the board.

drawing lines at various angles. A tapered shank 3.6 on the spider is provided,"and

Another object is to so construct the board th shank shouldextend into a socket ,(not that a drawing maybe removed when partly shown)'sothat the board maybe quickly and completed and afterward returned without ateasily rotated to'brin'g any one of itsseveral edges tention to the question of aligning the drawing towardthe draftsman. I I

in its exact former position on'the board. The stand may include the conventional tilting- Other objects and advantages will become evimeans if desired, but any mechanism which" will dent as the invention is described in detail and keep the top of the board sloping toward the reference is made to the accompanying drawings draftsman atanangle'of three to five degrees in '30 wherein, any position to which it may be rotated will pro- Fig 1 is a perspective view of the drawing vide satisfactory operation. f board mounted on a conventional stand. The board may be made of any suitable ma- Fig. 2 is a top plan view of the board with an terial,-w'o'od or molded plastic be'ings'atisiactory.

35 angle in operative position. Wood'is indicated in the drawings, and, when 3'5 Fig. 3 is an enlarged fragmentary sectional used, should preferably be a close'grained wood view taken at 33 of Fig. 2- thru the board and such as hard-maple.

.the angle, showing the cooperating guiding Hard maple-plywoodwill meet the requirements means and the sunken panel into which of low cost and *still be substantially non-warp the sheet of drawing paper fits. ing, the lattefrquality being highly important in '16 Fig. 4 is a still further enlarged fragmentary a device of this-character; 7 sectional view taken diagonally at 4-4 of Fig. 2 A'sunken panel 38 in the center of the' board showing the paper clamping means and the manhas Lalengthand'widthequal to that of the sheet ner of treating the board to keep the top of the f p o be use Assu for illustrative clamp at a height not above the top surface purpose, 'that/th'e' :deviceiherein shown is 'in I5 of the Damn tended :to be tusediin the makingof "Patent Ofiice Fig. 5 is a plan View of an adjustable tool in drawingath Panel tell y fi teen the nature of a T square having guiding means inches. .r-Its depth may preferably be as mucha's for cooperating with the guiding, means on the the thickness of'threesheetsof three-ply'Patent board. Ofilce Bristol inboard. 0

Fig. 6 is a fragmentary sectional view taken at Near the four corners of the panel Mat 40, 6-6 of Fig. 5 thru the guiding means and pivot the panel starts to become deeper, sloping gradu- ;pin .upon which the blade of the tool turns. ally downward toward the .corne'rs ('see- Fig. 4) to Fig. 7 is an edge view of the tool shown in form depressions AZforthe'toes M of the clamp 5 Fig. 5. I bolts 46. -Theit'oes 44:01 the bolts are sloped on Bristol board 50 is clamped between a toe 44 and the u e u fa Of h ad of Mack."-

Thumb; nuts 52 for'tighteningthebolts 4 6 are held against the bottomof the boardby themetal strips 54 which are secured to the underside of the board by the screws 56. nuts are loosened the toes 44 areraised-from the top of the paper and a drawing may be removed.

Slots in the top of the board for 'thetoesl l, ex tending from the bolt hole diagonally into the panel, keep the bolts from turning.

Close up to the panel 38 onthe 11mg sides the guide grooves 58, and on the shortsiiies; the

guide grooves 60. The guide grooves shown are V shaped and .placed just far enough from the panel to make space between the panel "and grooves for the holes forv the clamp bolts '46. I No partof the clamp bolt holesshouldintrude either on the panelor'. on the guide grooves. The-two guide grooves of each pair should be parallel with the sides of the panel and parallel with each other, and the grooves of one pair at right angles to the grooves of the other pair. N 1

'.Where the board is intended for making Patent Office drawings, the outside dimensions are preferably about twenty-twoinches square with the four corners cut on asshown at 6l. This size will permit the draftsman .to look directly down on any part of the panel; andwill permit the board being turned on the shank ,36without interference. with his body'g' if f' r Shown cooperating with the boa'rd .30in Figs. 2' and 3 is the thirty-sixty angle 62. The angle proper may be made of hard rubber, Celluloid, or molded plastic, preferably ofatransparent sheet notmuch over .06 or .07 inch thick. The guide bar 64 may be madeby flattening opposite corners of a square bar asat 66, then butting a slot'lengthwise in one of the flattened edges as at 68 and cementing the angle proper-in theslot. A relatively long guide barlis 'providedfby extending "the angle near the base as atJll.

The bar 64 may be made of hard rubber, molded plastic, or hard wood. ,Its size should be so selected that, in the f nished angle, the angle will be raised slightly away from the upper surface of theboard as at 12, Fig. 3, when the bar 64 is bottomingin a groove; 58 ;or 60.; This will minimize rubbing between the angle and the drawing as the angle passes thereover. Due to the fact that the angleis made fromrelatively thin sheet stock it may be pressed against the 'surface of the drawingwhenever this is desirable by the weight of the hand. Since the guide bar 64 is made V shaped both top and bottom, it will be apparent thatthe angle may be turned upside down from the position shown.

Fig. 10 shows a figure mademp of. anumber of straightjlines, allof which .were made. with an angle such as is shown'in Fig. 2, part of the lines with one surface of the. angle. upward and part with the other surface upward. By-providing an additional angle havingfifteenand fortyfive degree sides instead of .the' rig'htlangle and thirty degree sides-of the angle shown,'the angles of Fig. 10 may all be bisected.

y The tool shown in Fig. 5 is provided-for -all irregular oblique lines. Fig;- 9 shows'Ja seriesof When the thumb oblique lines drawn without resetting the tool. It comprises a guide bar 14 which may be made by flattening two opposite edges of a length of square hard rubber rod as at 16, Fig. '7. Opposite ends of the rod are provided with holes which terminate in a pointed seat 18 at the bottom. Metal plugs 80, correspondingly pointed are slidable in the holes. The outer ends of the rod are tapped for the knurl head screws 82 which may preferably be made of {hard fibre or similar material. The blade 84, which may be of rubber, Celluloid, or the like, has a circular head 86 and the v guide bar 14 is slotted thru to receive this head snugly but movably. The plugs 80 are also slotted as at 81 from the pointed end to near the blunt end, the slots also being such as to receive the blade snugly.

A pin 88 extends thru the bar and blade to provide-hinge means upon which the blade may be turned. Tightening the screws 82 forces the tapered. inner ends of the plugs into the seats 18 thereby clamping the edges of the head 86 and holding it in any position to which it may have been turned.

The heads of the, screws 82 should be small enough'ito clear the guide grooves 58 and 60 of the board. Obviously, when the blade 84 is once set to a given angle, the bar 14 may be laid in any one of the four guide grooves and with either surface of theblade upward.

In operation the angle 62 shown on the board in Figs. 2 and 3wil1 have the widest use. Assume, for instance, that two lines are to be drawn at right angles to each other such as the lines 90- and 92, Fig. 10. The line 90 would, of course, be drawn with the guide bar 64 of the angle 62 in a guide groove 58, Fig. 2. The hand should be laid on the angle near the guide bar 64 while the line is being drawn. Only moderate downward pressure is required to maintain the position of the angle. 7

Now, in order to draw the other line 92, it is not necessary to pick up the angle and lay it down-again with the guide bar 64 in the other guide groove60, but instead, after drawing the line 90, the pressure of the hand on the angle is first lightened, then the board itself turned a quarter turn with the other hand. The turning of. the board itself will force the guide bar 64 out of the groove 58, and when the groove 60 comes around to the-position before occupied by the groove 58, the guide bar will drop into groove 60 naturally where it may again be held with moderate downward pressure of the hand while the line 92 is being drawn.

, It will therefore be seen that one of the chief advantages of the equipment lies in the'fact that the draft'sman is not required to adjust his body to a position suitable first, for drawing a vertical-line, then, for drawing a horizontal line, but the line to be drawn is quickly and easily brought to the most convenient position for drawing it, and the angle quickly and easily finds its place and drops into position.

Having described one embodiment of the invention'in which sizes of parts, and materials therefor, have been suggested, it will be understood that these suggestions are not to be taken as limiting the invention further than defined in the appended claims, wherein,

I claim:

1. Drafting equipment comprising, a board havinga pair of widely spaced apart parallel guide grooves extending across the top surface thereof, and a like pair at right angles to the first, thereby leaving space for securing a drawing between the grooves, a blade adapted for ruling lines across said drawing, a guide bar pivotally secured to one end of said blade whereby said blade may be extended at various angles from said bar, said bar having two parallel guide ribs extending one above each side of the blade, each slidable in any of the four said grooves.

2. The structure defined in claim 1 with means for clamping the blade with respect to the bar in any of its angular positions.

3. Apparatus for making drawings of a fixed dimension, comprising a drawing board enough larger than the drawing sheet to allow a substantial margin around said sheet and having a sunken panel of the size of the drawing sheet and deeper than the sheet thickness, a pair of guide grooves at the ends of the panel parallel therewith and parallel with each other and a pair of guide grooves at the sides of the panel parallel therewith and parallel with each other, the one pair being at right angles to the other, the grooves being slightly away from the edges of the panel thereby enclosing a space slightly larger than the panel, the grooves crossing each other at the corners of the enclosed space and extending to the edges of the board, clamps for holding the drawing sheet to the bottom of the panel, secured to said board only in the margin between the panel and the space enclosed by the guide grooves, and not encroaching either on the guide grooves orv on the panel, except for the toe ends extending laterally from the clamps it so that the tops of the toes are no higher than the top of the board, and a ruling blade having a cooperating guide piece at its end adapted to slide in either of said grooves from one end of the board to the other without interference with said clamps while said blade passes over said panel and the tops of said clamps.

4. The structure defined in claim 3 wherein the guide grooves and the cooperating guide piece are V shaped.

5. The structure defined in claim 3 wherein the guide grooves and the cooperating guide piece are V shaped, the V being of degree included angle or greater.

6. The structure defined in claim 3 wherein the clamps are bolts extending vertically thru the board in the margin between the panel and the space enclosed by the guide grooves, the toes are L shaped ends at the upper ends of the bolts extending laterally from the bolt holes thru grooves in the top surface of the board over the panel, and the operating means are nuts below the board on the bolts.

7. The structure defined in claim 3 in combination with a drawing stand having pivoting means for turning the board on an axis at right angles to the plane of the board.

FREDERICK W. COT'I'ERMAN.

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