US1395200A - Drawing-board - Google Patents

Description

'L. WLMOORE.

DRAWING BOARD.

APPLICATION FILED MAR. 17, 19 9.

5 Patented Oct. 25,, 1921.

2 SHEETSSHEET I.

anvewi oz L. W. MOORE.

DRAWING BOARD.

APPLICAT4ION FILED MAR. 17. 1919.

1,395,200. a ted 00th 25, 1921.

2 SHEETS-SHEET 2.

' UNITED STATES;

PATENT OFF-ICE.

LEON w. moons, or sm'ra'mm, cmroimm DRAWING-BOARD.

To all whom it may concern:

Be it known that-I, LEON W. Moons, a

citizen of the United States,residing at Santa Maria, in the county of Santa Barbara, State of California, have invented certain, new and useful Improvements in Drawing-Boards;

and I do hereby declare the following to be a full, clear, and exact description of the in ,vention such as will enable others skilled in the art to which it appertains to makeand use the same. v

The invention relates to a drawing board and more particularly to the class of drafting boards adapted for ofiice and field use.

The primary object of the invention is, the provision of a drafting board of this character, wherein a piece of work can be laid out with accuracy so that the correct angles can be had and the proper measurements determined with despatch, and in event of an error the same can be detected without requiring the assistance of a small protractor when the board is being used for small office work or in the field, which in the latter use will serve as an ordinary transit.

Another object of the invention is, the pro vision of a drawing board of this character,

wherein the construction thereof is novel in form to assure intricate character work to be plotted either in an oflice or in a field so that any desired angle may 'behad with accuracy and the degree disposition thereof determined with despatch.

A further object of the invention is, the provision of a board 0 this character which is extremely simple in construction, readily and easily operated, thoroughly eflicient in its purpose, strong,-durable and inexpensive to manufacture.

With these and other ob'ects in view, the invention consists in the eatures of construction, combination and. arrangement of partsas will be hereinafter fully described, illustrated in the accompanying drawing and pointed out in the claims hereunto appended.

In the accompanying drawing:

F i re 1, is a top plan view of a drawing boar constructed in accordance with the invention, the board being shown by full lines and by dotted lines .is indicated a piece of work and a T-square for the drafting of an angle line in the use of the board.

Fig. 2, is an edge-elevation thereof.

Fig. 3, is a sectional. view on the line 33 of Fig. 1. Y

Specification of Letters Patent. 'Patented Oct, 25, 1921,

Application filed March 17, 1919. Serial No. 283,111. I

Fig. 4, a plan looking oppositely from v Fi 1. v i Fig. 5, is afragmentaryenlarged vertical sectional v1ew showing in detail one of the countersunk 1 nuts. I

Referring to the drawingv in detail, A,

designates generally the drawing board which comprises the rectangular body sect1on 10 preferably. made from wood and'of the requlred size in length, width and thickness, which is formed with a circular rabbeted central opening 11 ,in which is fitted the circular board section 12 formed with a rabbeted marginal edge 13 to overlap the rabbeted edge of the opening 11 in the section 10, so that the opposite faces of the section 10 will be flush with the opposite faces of the circular board section 12.

Mounted between the rabbeted edges of the sections 10 and 12 at desirable intervals are cups bearing balls 14 which permit smooth and easy movements of the sections with respect to each other. Concentrically of the center opening 11 on the section 10 are suitably marked or otherwise indicated on each face thereof independent scales 15 graduated into degrees of a circle, namely On the section 12 is printed or otherwise marked a north indicator 17 while at 18 is printed or marked a south indicator to coso as to frictionallyfour points thereof equally distant from each other are countersinks or recesses 21 in which are fitted nuts 22 forming threaded sockets for the detachable mounting of the board A upon a tripod for the use-0f said board in a field, the recesses 21 being normally closed through the medium of removable plugs 30 when the said board is adapted for office use.

Suitably counterseated within grooves in the face of the section 10 which is opposite to that face of the section 12 in which the recesses 21 are formed and near the left hand ends of the north and south edges thereof are hinged folding sights 25 and 24 respectively, normally lowered to inactive position, but adapted to be raised at right angles to the face of the board A when it is used for field work.

To operate the board for ofiice workthe side thereof in which the recesses 21 are formed is uppermost. A piece of work as indicated by B in Fig. 1 of the drawing is tacked or otherwise enga ed on the board.

It is to be noted that t e left hand'edge portion of the section 12 is designated 'as east, while the right hand edge portion is designated as west.

In order to plot a line with the course of north 20 west, the. section 12 is revolved to the right into the northwest quadrant of the circle until the indicator 17 coincides with the 20 mark on the graduated scale 15 on the section 10 of the board which disposes the piece of work B angularly as indicated by the dotted lines in Fig. 1, of the drawing.

A T-square as indicated by C in Fig. 1 is operated back and forth along the south edge of section 10 with the blade of the T-square extended at all times north and south; and as shown in Fig. 1, by positioning the T-square at a bearing of 20 west from any point on the section 12, the

desired line can be indicated. It will be apparent that any bearing in any direction may be plotted.

To operate the board in the field, the same may be supported upon a tripod of any approvedtype by engaging the tripod in the sockets 22 after removing the plugs 30, the board being reversed from the position shown in Fig. 1 for this purpose. The center of the board must be at the center of the tripod when the said tripod is accurately set,

. thereafter the folded sights 24 and 25 are raisedwith one of the same positioned at the north end and the'6ther at the south end. The section l0'may now berevolveditbout the section 12 which is stationary. The

cators are set at zero and the rear sight is taken the same as that with the transit on any object ahead and by the use of the T- square C operating at the south edge of the section 10 a line can be drawn from an desired point and distances scaled.

From the foregoing it is thought that the construction and manner of use of the drawing board will be clearly understood and therefore a more extended explanation has been omitted; i

What is claimed is:

1. A drawing board of the character described, comprising a straight edge section having a circular opening, a center section shaped "to fit the opening and revoluble: therewithin, said straight edge section having degree marks of a circle thereon around its opening and said center section being provided with indicators coacting with said marks, and foldable sights carried by one face of the straight edge section for alinement in with diametrically opposite points of the same.

3. A drawing board of the character described, comprising a square section having a circular opening rabbeted around its edge, a round center section fitted to the opening and having a rabbeted edge cooperating therewith, antifriction means interposed between the rabbets, said square section having degree marks of a circle thereon and said center section being provided with an indicator coactin therewith, and foldable sights carried by t e square section Within two grooves in one face thereof adjacent diametrically opposite points of the same.

In testimony whereof, I aflix my signature.

LEON W. MOORE.

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