US1906300A - Drawing board - Google Patents

Description

May 2, 1933. w. E. YAxLr-:Y LQOG@ DRAWING BOARD Filed Dec. l1, 1951 Patented May 2, 19.33`I

PArsar ortica WILLIAM E. YAXLEY, 0F OAK :PARKr ILLINOIS DRAWlNG- BOARD Application filed December 11, 1931. Serial No. 580,235.

This invention relates to drawing board, and'm'ore particularly to boards suitable for home, oflice and school use.

Among other objects the present invention aims to generally improve and simplify the construction and operation of devices of this character and especially to provide simple and effective means for retaining a sheet of'paper thereon without the use of i thumb tacks.

The invention is desirably inclusive of a spring controlled clamping bar on the drawing board and unitary means beneath the bar for securing the clamping bar in clamping position against the action of the spring.

The invention i will be more fully explained in connection with the accompanying drawing showing an illustrative embodiment thereof, in which- Figure l is a plan view of my improved board;

' Figure 2 is a bottom view of the same, being a view of the board of Figure lrotated 180 degrees;

Figure 3 lis aV section taken on the line 3-3 of Figure 1; and Y Figure l is a fragmentary section taken on the line 4 4 of Figure 1.

Referring in general to the figures of the drawing, I have shown a board 1 made of suitable Wood having a drawing surface 2 which is desirably bordered by the raised margin 3 of the board 1, for a purpose presently pointed out.

For the usual drawing or sketching purposes, a sheet of paper 4 is superposed upon the surface 2 and I provide simple and eilie.

cient means for retaining the paper Il in a given position on the surface 2, such means including a clamping bar 5 and unitary means such as the locking bar 6 beneath the board 1 for clamping the clamping bar 5 against the paper throughout the length of the clamping bar with but one movement of the hand of the user.

The bar 5 is desirably of metal and is shown in the form of a shallow inverted channel extending the length of the surface 1 2 and having a relatively sharp edge 7 which grips the paper 4 through the operation `of the mechanism next described.

In Vthe illustrative construction, the barf is riveted to a plurality'of tubular members- 8 (in this case there are three such members) which are spaced at appropriate-intervals along the bar and each of which members passes loosely through a cylindrical aperture 9 in the board 1 and s'lidably` into a tubular bushing 10 fixed in the lower mouth of the aperture 9. The Vbushing lOhas a laterally disposed annular flange 11 which laps the bottom of the board 1.y Each tubular member 8 is advantageously split and slightly contracted at its lower end as at 12 ist and threadedly receives a retaining screw 13 which is thus gripped bythe `member` 8 against accidental movement. The screw 13 may be adjusted in the member 8 to lengthen or shorten the distance betweenA its head 14 and the clamping bar The head 14' may be grooved as at llla to be turned by a screw-driver. Different thicknesses of paper, for example, may therefore be accommodated, y

The locking bar 6 is disposed between the heads 14C of the screws 13, and the flanges 11 of the bushings 10, the locking bar having slots 415 through which the screws 13 pass. The slots 15 are elongated longitudinally of the bar 6 and by means of the handle 16 the bar 6 may be moved longitudinally in'either direction to have one end or the other of the slots 15 between the head 14 and the flange 11.` A portion of the bar 6 margining one end of each of the slots 15 is inthe plane of the bar While a portion of the bar margining the other end of the slots is offset from the plane of the bar to form the cam rises 17. Thus when the bar is placed, by means of the handle 16, in one of its extreme positions, the cam rises17 are disposed between the flanges 11 of the bushings 10 and the heads 14 of the retaining screws 13 and the members 8 are moved to the limit of their downward movement in the bushings 10 pressing the clamping bar 5 against the drawing surface 2 with the paper held against movement therebetween. y

Conversely, asshown in Figureg, when the bar 6 is moved to its other eXtreme position, the portions of the bar 6 margining the slots 15 in the plane of the bar are disposed between the flanges 11 and the heads 14, permitting the members 8 to move to the limit of their upward movement in the bushings 10 and the clamping bar 5 is thus permitted to move away from the drawing surface 2 to cause the paper 4 to be released.

To insure that the clamping bar 5 will be normally spaced vertically from the drawing surface 2 when the locking bar 6 is in releasing position, I have provided spring means for forcing it away from the board except when it is pressed thereagainst b y the locking bar 6. In the present exemplification, I have shown a compression coil spring 8 barrelled in each of the apertures 9 and abutting at one end against the bushing 10 and at the other against the bar 5. Thus when the locking bar 6 is in the position shown in Figure 4, the coil springs 18 will force the members 8 upwardly in the bushings 10 and cause the bar 5 to be spaced from the surface 2, permitting ready insertion of the paper 4 thereunder. W'hen the locking bar 6 is moved to its other operating position, as shown in Figure 3, the bar 5 is moved downwardly against the action of the springs 18.

As I have shown in Figure 1, the bai` 5 may advantageously be used as a scale by being marked off in inches or other measurement graduations.

The board 1 is desirably inclusive of a rectangular frame 19 here shown integral with the board 1 upon its under side, which serves as a base for the board and at the same time elevates the main body of the board above any object upon which it may rest, so that the locking bar 6 will be unobstructed and readily accessible.

The margin 3 of the board being als elevated slightly above the clamping bar 5 permits a T-square to be moved across the drawing surface 2 without interference from the clamping bar.

Vhen the board is turned upside down, as shown in Figure 2, the frame 19 may also be used as a receptacle for drawing instruments, Qi the like.

Having described one embodiment of my invention, I claim:

1. In a drawing board, the combination of a drawing surface, a clamping bar normally spaced from said surface, means including a unitary locking bar lying parallel to the clamping bar and movable longitudinally of the board on the opposite side of the board from said surface for clamping the clamping bar against the said surface against the action of the spring, and means for transmitting movement of the locking bar to the clamping bar.

2. In a drawing board, the combination of Vurging said bar into said spaced position, a

member secured to the bar and passing through the board, and means beneath the board for moving said member downwardly to clamp the bar against the surface against the action of the spring.

3. In a drawingV board, the combination of a drawing surface, a clamping bar normally spaced vertically from said surface, a spring urging the bar away from the surface, a plurality of members secured to said bar and passing through the drawing board, and unitary means beneath the drawing board for moving the members in one direction to clamp the bar against the drawing surface against the action of the spring.

4. The structure of claim 3 wherein the unitary means comprises a locking bar having slots for the passage of said members and having cam rises at one of the ends of the slots.

5. The structure of claim 3 wherein the unitary means comprises a locking bar having slots for the passage of said members and having cam rises at one of the ends of the slots, and wherein the locking bar engages the said members through the intermediation of an adjustable retaining screw.

6. The structure of claim 3 wherein the board has a raised margin bordering the drawing surface to elevate a T-square above the clamping bar.

7. The structure of claim 1 wherein the board has a base for elevating the locking bar above an object on which the board is placed.

Inwitness whereof, I hereunto subscribe my name.

WILLIAM E. YAXLEY.

Images