US2632975A - Drafting device - Google Patents

Description

March 3l, 1953 o. KLABUNDE DRAFTING DEVICE 2 SHEETS-SHEET l Fil'e d Feb. 24, 1951 March 31, 1953 o. KLABUNDE 2,632,975

` DRAFTING DEVICE Filed Feb. 24, 1951 2 SHEETS- SHEET 2 IN V EN TOR.

dif@ Zwama@ Patented Mar. 31, 1953 UNITED STATES ATENT OFFICE 4 Claims.

The present invention relates to drafting devices, and has for its main object the provision of a board for receiving in an encompassing relation an endless drawing paper.

A further object of the present invention is the provision of means in a drawing board whereby an endless paper sheet may .be held ina taut relation with a board. Another object of the present invention is the provision in association with one edge of a drawing `board of a roller held under a yielding tension to or away from the board, so that when an endless sheet of paper is passed around the board and over the said roller, the latter, normally under :a pressure away from the board, may maintain the sheet in a stretched relation with the board, said roller being capable of manual depression towards the board for the purpose of slackening the endless paper sheet so that the latter may -be shifted around Ithe board.

Another object of the present invention is the Vprovision of a suitable mechanical means Whereby the endless paper sheet may be shifted around the board.

A still `further object of the present invention is the provision of a suitable removable guard at one edge of the board for guarding an endless paper sheet therearound against scratching or soiling.

With the Iabove general objects in view land others that will appear as the invention is better understood, the same consists in the novel `construction, combination and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawings and pointed out in the appended claims.

In the drawings forming a part of this applica- 'tion and in which like designating characters referto corresponding parts throughout the several views: l Fig. l is a top elevational View, partly in section, with' an endless paper sheet in an operative position therewith; Y

Fig. 2 is an end elevation-al View of the board,

along thefront or near edge thereof; L Fig. 3 is a side elevational View of the board,

on a reduced scale;

Fig. 4 is an end elevational view of the board, partly in section,` along the rear or far edge thereof;

Fig. 5 is a near end elevational view of the board, with a mechanism cooperating with that end for shifting the endlessl paper sheet around the board; A

' Fig, 6-is a side elevational view of the board, in-

l not extend across wings I 2.

cluding the end view of the mechanism shown in Fig. 5 for mechanically shifting the paper sheet around the board; and

Fig. '7 is a transverse cross sectional view through the mechanism for mechanically shifting an endless paper sheet around the board, with a cross section of 1a guard overlying the paper sheet adjacent the front end of the board.

Referring to the present drawing in detail there is shown therein board IB, adapted to receive in an encompassing relation an endless sheet of paper II. Said paper sheet II is narrower than the width of board IB, so that the side edges of board I0 extend beyond the side disposed upon one face of each cleat I3, While anequal number thereof is disposed adjacent the opposite face of each cleat I3. The lower ends of said clamping members I4 enter longitudinai recesses I6 along each face of cleat I3. By virtue of nthis arrangement cleats I3 may be shifted ilather towards the front or the rear end of board Aifixed to the front or near end of board I0, including Wings I2, by means of screws I'I, is an edge piece I8, segmental on a transverse cross section, with its arcuate face disposed outwardly.

lWhile the upper edge of sai-d edge piece I8 remains flush with the upper face of board I0, including wings I2, the lower edge thereof remains in a spaced relation with the lower face of the board and wings I2, as is clearly seen in Fig. 3, for the purpose hereinafter specied.

Adjacent the rear or farther end of board Il) roller I9 is positioned in a spaced relation with board Ili. Said roller I9 may be slightly longer than the width of paper sheet II. Its ends do The upper edge of said roller I 9 remains on the upper plane of board I 0, while the diametrically opposite portion of the rollers periphery extends below the lower plane of said board I0. By virtue of this arrangement said roller I9, in cooperation with the downwardly extending edge of edge piece I8 maintains the lower portion of paper sheet II in a spaced relation with the lower face olf board I0, while the upper portion of the endless paper sheet remains in contact with the upper face of said board I0, as is clearly seen in Fig. 3. It is of course only the upper portion of the endless lpaper sheet which remains in contact with board I0, which is to receive sketching or drawing impressions.

Each of the ends of roller I9 carries shaft 20 in a concentric relation with the said roller. The inner end of said shaft 26 may be threaded whereby said shaft may be driven into the roller. Integrally formed with each shaft 20 is collar 2|, which is in a spaced relation with the outer termination of said shaft 29. Loosely positioned upon shaft 26 is wheel or bearing 22, for which collar 2| acts as a stop from one outer face thereof. Loosely positioned upon said shaft 20 and interposed between the end of roller I9, and the adjacent inner face of wheel 22 is an annular spacer 23. By virtue of this arrangement wheel 22 i's capable of rotary movement around shaft 2l), but is incapable of longitudinal shifting movement lin relation therewith.

Aixed by means of screws 29 to the rear end o f each wing I2 is plate 25. Either integrally formed with said plate 25, or rigidly aflixed thereto, either by soldering or otherwise, is leaf spring 26, of a generally U-shaped formation, the bight of which extends downwardly and beyond the lower face of'board I9 and wings I2, as is best seen in Fig. 6. The opposite end of said spring 26 terminates in an inwardly wound coil 21,

which encompasses and rigidly engages wheel 22. l

`From the hereinabove description it will be noted that roller I9 is supported and held in an operative position with relation to board I0 only by means of a pair of springs 26, one coacting with each end of said roller I9. Normally, said springs 26 tend to urge said roller I9 away from the adjacent end, that is rear or far end, of board I0, for the purpose of maintaining the endless paper sheet in -a stretched and taut condition with relation to board I0, when said paper sheet is passed over said edge piece |8and said roller I9. n

' The parts already described render the invention essentially operative. To make endless paper sheet II, a longitudinal strip of paper is passed over edge piece I8 and roller I9, and thereupon the ends of a paper strip are joined by a Scotch tape or any other means. Before the ends of the paper strip are joined it is advisable to manually depress roller I9 toward board I9, against the tension of springs 26, in order to eliminate any slack in the endless paper sheet which is ultimately to be formed. When the ends of a paper Strip have been joined, the manual pressure against roller I9 is eliminated, and springs 26, tending to press away Vfrom board I9, exert pressure upon the formed endless papersheet in order to maintain the latter in a stretched and taut condition with relation to board I0.

Rather than to use manual operation for 'depressing roller I9 for the purpose describedin the last preceding paragraph, suitable mechanical means is Aprovided for the purposejof main,- taining roller I9 shifted towards the adjacent end of board I9 while a paperendless sheet is being prepared around the drawing board. That means includes arm 28, hingedly connected t-'o each plate 25 at lugs 29 extending from `each of said plates 25. The opposite free end of each arm 2 8 is provided with opening 30. When, said Varms 28 are Vraised into a vertical 'position 'with relation to plates 25, the free ends of shafts 20 are not in alinement with openings 30, but are farther removed therefrom towards the ends of arms 28, due to the action of springs 26. When however roller I9 is manually pressed towards the adjacent end of board IU the free ends of shafts 20 will eventually come into an alinement with openings 36, provided that arms 28 are held substantially in a vertical position` with relation to plates 2.5. When thev free ends of said shafts 20 come in alinement with 'said openings 30 arms 28 are then swung towards said shafts 20, until the shafts enter said openings 30, the position indicated by dotted lines in Fig. l. When in that position shafts 20 and through them roller` I9V 'are effectively locked to said arms 28, rendering springs '26A inoperative, thereby bringing about a position of roller I9 which is rigid relative to board I0. When, in that position of roller I9 with relation to board I0, a strip of paper 1s passed over edge piece I8 and said roller I9, and the ends of the paper strip are joined for effecting an endless paper sheet II around board I0, as is clearly seen in Figs. l, 3 and 6. It is noted that the paper sheet formed around the 'board by the operation last hereinabove described is reasonably stretched andtaut with relation to board I0, edge piece I8 and roller I9. 'When however arms 28 are swung into their inoperative position, that is away from their engagement with shafts 26, the full lines position illustrated in Fig. l, roller |9 is then free to shift laway from the adjacent endof board Illdue to the actions of springs 26, thereby removing any slack that might have existed in the endless paper sheet after it was formed around board I0.

Manual depression of vroller I9, as well as the pressure exerted thereagairist by the endless paper sheet II, may eventually cause said roller I9 to assume a bent formation. To guard against this suitable mechanism is provided whereby the roller may be pressed at all times away from the adjacent end of boardv I6. This means, best shown in Fig. 1, includes cylindrical tube 3| fric.- tionally held within'bore 32. made within Ytheend of board IU, which is adjacent to roller I9, Cylinidrical hollow Yplunger 3,3 is positioned within tube 3| for longitudinal movement therewithin. Tube 3| is provided with an inwardly extending indent 34 which enters key-way. 35v madefupon the periphery of plunger 33in alongitudinal direction, said key-way being open upon. the inner end of said plunger r 33. By virtueV of this arrangement plunger. 33 may readily be inserted within tube 3| with indent 34r made to enter key-way 35. It is clear that indent, 34, permits longitudinal shifting moi/ement` of plungerr 33 within tube 3 I, but prevents rotary movementof said plunger 33 within said tube 3|. Coil spring 36 is extended within the cavity of p1unger33. to bear against thebottom Of bore 32 in order to, normallytend to shift said plungerV 33 out of tube 3|. Integrally formed with saidfplunger sa is an enlarged heauai, said boren at its outer end being, enlarged` in order to acc-ommodate therewithin said head 3.1. The enlarged portion of bore 32 affects shoulder-38, with which the adjacent end of tube` 3| terminates, and which forms -a stopfor head 31, preventingv its further inward shifting. At the outer end head 31 carries wheel 39, journalleduponp'in 'for 'rotary movement.

Coil spring 36 urges wheel v'39.in ycontact with roller 9 an d exerts pressure thereon tending'to urge saar-011er 'fs away 'from the -iadjaceritena of board I0. By virtue of this arrangement deformation of roller I9 is prevented which other- Iwise might ensue due to repeated manual shifting of roller I9 toward board IIJ, as well as due to theconstant pressure thereagainst by the endless paper sheet II. If roller I9 is unduly long the same may require a plurality of the counter-pressure devices including plunger 53, head 31 and wheel 39.

It is further observed that due to the fact that wheels 22 are loosely positioned upon shafts 20, roller I9 is capable of rotary movement without interference from said wheels 22 or springs 26. As the drawing upon the endless paper sheet II progresses from the rear or far end of board Il] toward the near or front end thereof, the endless paper sheet may readily be shifted around the board by merely exerting pressure by fingers upon the upper portion of the paper sheet and shifting the paper sheet upon the upper face of board I0. This operation will of course shift the endless paper sheet II around said board I as well as over said edge piece I8 and roller I9.

If however the paper sheet is unduly long it may then be desirable to shift the paper sheet around the board by mechanical means. Such means, best illustrated in Figs. 5, 6 and 7, includes arcuate channelled strip 4I, positioned forwardly of the front edge of board I0. Said strip 4I has an integrally formed extension 42, projecting from the lower edge thereof. Said extension 42 overlies the lower face of board Ill, adjacent its front end, and is there afxed by means of screws 43. It is understood that strip 4I and extension 42 may be made in a plurality of pieces spaced lengthwise of roller 44.

Roller 44 is positioned within the cradle of said strip 4I, for a free rotary movement therewithin. Said roller 44 is mounted upon shafts 45, which are in a rigid, concentric relation with said roller 44. Each shaft 45 is freely journalled within bearing llili, which is integrally formed with and extending from plate 41. Each plate 41 is affixed, by means of screws 48 to the front end of each wing I2. Integrally formed with each shaft 45 is a spacing collar 49 which is normally interposed between the adjacent bearing 45 and the end of roller 44. By this means roller 44 is prevented from longitudinal shifting movement.

One shaft 45 is extended slightly beyond the outer side face of one wing I2 and is provided with a longitudinal keyway 50, within the outer end of which a comparatively short key 5I is inserted and there rigidly held. Freely rotatable upon the portion of that shaft 45, which remains between said key 5I and bearing 46, is collar 52, with the outer end of which crank 53 is integrally formed and radially projects therefrom. Handle 54 connects with the opposite end of said crank 53.

Collar 52 on its inner periphery is provided with a plurality of radially extending slots 55, as is seen in Fig. 6. When said collar 52 remains shift-ed towards the adjacent bearing 46, the same remains out of engagement with key 5 I because the latter does not extend within any one of slots 55. In that position crank handle 53-54 remains inoperative and roller 44 may rotatably shift with both of its shafts 45, without in any manner aifecting collar 52 or its crank handle. The latter simply hangs down, as seen in Fig. 5.

Thus, endless paper sheet I I may be manually shifted upon board III and around and with rollers I9 and 44 Without aiecting collar 52 and its crank handle.

When however it is desirable to use the crank handle, collar 52 is longitudinally shifted away from bearing 46, with key 5I entering one of said slots 55, until crank 53 is well past the plane co-extensive with the side face of the adjacent wing I2. This will permit turning of the crank handle without interference from wing I2. This in turn will impart a rotary shifting movement to shaft 45 which carries said collar 52, and this in turn will cause rotatable shifting movement of rollei 44. The rotation of roller 44 will necessarily cause the shifting movement of the endless paper sheet II`.

The portion of the endless paper sheet II stretched over either said edge piece I8 or roller 44, as the case may be, may become soiled or scratched when in contact with a draftsmans 'hands or clothing, particularly when the endless paper sheet II has been worked upon for a comparatively long time without frequent shifting. To guard against soiling or scratching of that portion of the endless paper sheet II, a suitable guard therefor is provided. The same includes an arcuate, trough-like member 56, which in its operative position overlies and remains in contact with the endless paper sheet II stretched over roller 44 or edge piece I8, as the case may be, as is best seen in Fig. 7. Integrally formed with each end of said member 56 is substantial-ly U-shaped wall 51, each of which is adapted to frictionally grasp the adjacent bearing 46 in a clamping relation, as is seen in Fig. 6. From this construction it will be readily seen that guard 56 easily snaps on and off from roller 44 or edge piece I8, as the case may be, and thereby effectively shields the portion of the endless paper sheet Il overlying said roller 44 or edge piece I8, as the case may be.

Only slight modification of said guard 56 in order to adapt the same for use in connection with edge piece I8 need be had. All that is required is the elimination of walls 51 at the end of member 56, and making said member 56 resilient to snap on or off said edge piece I8.

It is to be understood that endless sheet of paper II may have under it an endless wing or apron which would of course shift with said endless sheet of paper I I.

While there is described herein a preferred embodiment of the present invention, it is nevertheless to be understood that minor changes may be made therein without departing from the spirit and scope of the invention as claimed.

What I claim as new is:

1. A drafting device comprising a board, a roller adjacent one end of said board, said board and said rollerl being adapted to receive an endless sheet of paper in an encompassing relation, a wheel journalled at each end of said roller, and a pair of leaf springs anchored by one of their ends to said board, each of said springs by its opposite end engaging one of said wheels, normally said springs urging said roller away from said board for maintaining the endless sheet of paper in a stretched condition.

2. A drafting device comprising a board, a roller co-acting with one end of said board, said board and said roller being adapted to receive an endless sheet of paper in an encompassing relation, means for normally urging said roller away from said board for maintaining the endless sheet of paper in a stretched condition, normally the endless sheet of paper exerting a force 7 uponA saidY roller` in the direction of said` board, and means in substantially anti-frictiorial` contact with the roller'. between the edgesof. said endless sheet resiliently. urged thereaganstf for counteractingv said forcewhile permitting rota,- tion of said'roller.

3. A drafting devicel comprising a.l hoard,- a roller co-acting with one end of saidzboard, said board and. said roller being,` adapted to receive an endlesssheet of papery inan encompassing relation, means for normally urging saidfroller awayfrom said board forimaintaining the-ende lesssheet. of paperlin a .stretched conditions nerr really the endless sheet' of. papery exerting pres: sure upon said roller in the; direc of; said board, anlmeans for-counter-actin eure, Said last named meansfineludine ins wheel meunied in saidbeardi, Seid e ,nf inse/.heel beinepoeiiiened iniermediately ne .end

0f seid roller,A Seid tensioning; wheeLeQntae 'ne the peripheryrof saidroHerin a transversevdirection for-urging-said roller away from, Saidboaifd,

4. A drafting device. comprising ay boar a roller cgi-acting- Wth: one end of saidboard, said board and said roller beingVadapted-to receive an endlessw sheetof, paperr in an encompassing relation, tensioning artica-ns.- carriedy bysaid board and-connected with saidV roller'for normally urgingthe latter awayffrom said board forV maintainingthe endless sheet of; paperin asstretched condition, and means for rendering-,said tensionngf means inoperative during application of the endless sheet o f'paper around, said board and Saidreliery said; last named: means: including a pair of arms hingedly connectedto saidboard, said arms beingadapted toengagefsaid roller for aininsthefsame in arigidpesitionwith relation tosaid heard,

REFERENCES;

The: following references are-oi record-1in the file,V of 'this patent:

UNITED-` STATES PATENTS Number Name; Date 397,421 Henley K Y Feb. 5, 1889 332,909 Homans Oct. 9, 1906 127,023,024- Sinclair Dec. 12, 1916 1,896,923 Tevonian Feb. 7, 1933 v215 2,603,908, Schwefel ,--s July 22, 1952

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