US1285279A - Plotting-board. - Google Patents

Description

J. D. McCABE.

PLOTTING BOARD.

APPLICATION man MAR. 5. 191s.

JUNIUS D. MGCABE, 0F CORAOPOLIS, PENNSYLVANIA.

PLOTTING-BOARD.

To all whom t may concern:

Be it lmown that I, J UNIUS D. MoCABn, ak citizen of the United States, and a resident of Coraopolis, in the county of Allegheny and State of Pennsylvania, have invented a new and Improved Plotting-Board, of which the following is a full, clear, and exact description. l

This invention relates to a plotting device and has for an object the provision of an improved construction whereby deed descriptions may be properly plotted without resorting to anything except the use of a pencil and paper.

Another object in view is to provide a device which may be taken to the recorders ofiice and a given piece of land properly plotted on a piece of paper practically from the record whereby' errors in transcribing will be eliminated.

A still further object in view is to provide an improved construction for laying out a piece of land from description wherein the drawing is done within the graduations of a protractor and thereby'minimize the varying in calculations as well as in execution.

In the accompanying drawing:

Figure 1 is a top plan view of a plotting board disclosing an embodiment of the nvention.

Fig. 2 is a section through Fig. 1 on line 2 2, the same being on an enlarged scale.

Fig. 3 is a section through Fig. 1 on line 3 3, the same being on an enlarged scale.

Fig. 4 is a detail fragmentary sectional View through Fig. 1 on line 4-4, the same being on an enlarged scale.

Fig. 5 is a detail fragmentary sectional view through Fig. 2 on line 5-5.

Referring to the accompanying drawing by numerals 1 indicates a base which may be made from wood or any other desired material on which disks 2, 3 and 4 are mounted. The protractor disk 2 is provided with a central aperture with avsupporting bearing plate 5 rigidly secured thereto by screws or other suitable means as shown in Fig. 2, said plate snugly fitting the cylindrical block 6 which is secured to the base 1 in any suitable manner, as for instance by screws 7. A stationary plate 8 is rigidly secured by screws or other suitable means to the cylindrical member 6, said plate being comparatively narrow and slidingly iitting in the supportin guide 9 (Fig. 5) which guide is secure by screws or otherwise rigidly to the disk 3, whereby said disk is Specification of Letters Patent.

Application led March 5, 1918. Ser1'a1 No. 220,593.

Patented Nov. 19,1918.

allowed a back and forth longitudinal movement. This movement is in a longitudinal direction and as disk 3 moves the disk 4 also may move. In addition to the longitudinal movement provided for disk 4 in this manner said disk 4 is allowed a latitudinal movement at right angles to said longitudinal movement. These movements both latitudinal and longitudinal are comparatively slight, but allow a proper adjustment of the disk 4 beneath the paper 13 which rests on the disk 4, said adjustment being provided in order that lines on the paper 13 may properly register with the directional lines 14 on disk '4. The longitudinal movement above described permits an adjustment for a major line to be brought under a given point onl paper 13 'for the purpose of scaling the re.- quired distance. As an example, calling the line undef the point naught, (major lines being one inch apart) and reading to the right 250 on scale of 100 to the inch,`you would count out five minor lines past the second major line for that distance. It will of course, be understood that a fractional distance would be proportioned between the minor lines. In order to cause this movement of disk 4 at right angles to the movement of disk 3 a tongue 29 is rigidly secured to the disk 3 as shown in Fig. 3 and slidingly fits the guides 30.. Stops 31 and 32 are secured to the tongue 29 so as to limit the sliding movement of the guides and the disk 4 to which they are rigidly secured.

AFrom this it will be seen that the disk 4 is substantially stationary though allowing a slight movement in a longitudinal and a latitudinal direction. The top disk 4 carrying directional lines minor lines 15 and 16 is held against an upward movement by a number of overhanging brackets 17 and acts as a table or supporting board for the paper 13 on which the drawing is to be made. This paper is held in a given position in respect to the protractor disk 2 by a maintaining clip structure 18. This clip structure is provided with a solid plate 19 having spring clips 2O thereon for gripping the paper 13 and a pair of spring members 21 formed with hook sections adapted to extend through any pair of apertures 22. Members 21 are resilient and normally are farther apart than apertures 22, so that in order that these members may be thrust through these apertures they must be somewhat compressed and thereby brought under tension so that they will ordinarily remain 14 and also the major and

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