US2419078A

US2419078A - Drafting device for drawing projections

Info

Publication number: US2419078A
Application number: US540582A
Authority: US
Inventors: Jessie T Ivy
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-06-16
Filing date: 1944-06-16
Publication date: 1947-04-15
Anticipated expiration: 1964-04-15

Description

April 15, 1947. J."r lVY DRAFTINGLDEVICE FOR DRAWING PROJECTIONS Filed June 16, 1944 2 Sheets-Sheet 1 INVENTOR. ML [2 JESS/ET luv 14 TTOE/VE YJ' April is, 1947. NY 2,419,078

DRAFTING DEVICE FOR DRAWING PROJECTIONS Filed June 16, 1944 2 Sheets-Sheet 2 5 J z /7 0 I 6 I I M 4 Z INVENTOR.

Patented Apr. 15, 1947 UNITED STATES PATENT OFFICE DRAFTING DEVICE FOR DRAWING 4 Claims.

This invention relates to drafting devices, and it has for its principal object to provide an apparatus for use in the drafting of projections from drawings of plans or elevations of objects, and to provide for the drafting of the projection at any desired angle of projection.

More specifically stated, the present invention resides in the provision of a drafting device or machine for the above stated purpose comprising a base member or board, having a plane surface on which a paper sheet or the like, may besecured to receive the projection thereon; another board having a plane surface on which the draw ing from which the projection is to'be made, may be secured; the latter board being adjusted relative to the first board, to the angle at which it is desired that the, projected drawings be made, a guide rail supported along the line of intersection of the two planes, a standard that may be moved along the guide rail, and a cross rod that is adjustable endwise in the upper end of the standard, and equipped at one end with a stylus whereby the lines of the drawing may be traced and, at its other end, with a marker movable in contact with the said paper sheet in accordance with movement of the stylus to define a projection of the drawing which will be at an angle of projection corresponding to that angle at which the drawing is disposed relative to, the surface on which the projection is made.

It is also an object of the present invention to provide a machine of the character above stated which is equipped, at the stylus mounting end of the cross rod, with means whereby the marker may be lifted from the paper by the hand which grips the stylus in use of the device.

Other objects of the invention reside in the details of construction of parts, in their combination and mode of operation, as will hereinafter be described.

In accomplishing these and other objects oi the invention, I have provided the improved details of, construction, the preferred forms of which are illustrated in the accompanying drawings where- Fig. 1 is a perspective view of a drafting ma-. chine embodying the present invention, showing it. as used in the making of a projection from a drawing.

Fig. 2 is an end view of the machine as seen in Fig. 1.

Fig. 3 is a plan view of the same.

Fig.4 is a cross section through a machine of an alternative form of construction.

Fig. 5 is a detail of the joint for the board supporting leg.

Referring more in detail to the drawings- In Fig. 1,.I have illustrated the present machine in a simplified form, comprising a rectangular base frame having opposite side rails l and 2, and opposite end rails 3 and A, all of which are rigidly joined. Fixed upon the side rails l and 2, at locations centrally between their ends, are bearing blocks 5 and 5. Between the blocks 5 and E, a cross bar I is fixedly extended.

Thebase frame ordinarily is disposed on a support lying in a horizontal plane for convenience inv use of the machine. Fixedly mounted on this base frame, at one side of the cross bar I, is a base or board 8. At the opposite side of thecross rail 1 is a board ill, and this is hingedly attached by means of brackets H to the bearin blocks 5 and 6. As seen in Figs. 1 and 2, the brackets are secured by screws ornails to the opposite end edges of the board, and secured at their ends by pivots E2 to the bearing-blocks. The means of attachment provides that the board It! may be hingedly adjusted from a position lying flatly upon the base frame, as shown in dotted lines at Illa; in Fig. 2, to any angular position, between the horizontal and vertical position, at which it might be conveniently used. It is generally the case, that the adjustment of board It! is not to be more than a 45 angle relative to the horizontal. For support of the board It at any position of angular adjustment, it is equipped with a pair of legs 85-45 which have upper ends pivotally attached to the under side of the board adjacent its outer edge, by a universal joint as at'ltl, and adapted to engage at their lower ends with the top edge of the cross bar 3 which is toothed as at I? to retain the legs against slippage. To lower the board, the legs are merely disengaged from the teeth and swung up against the under side of the board.

Each of the universal joints It by which the legs I5 are attached to the board H), comprises a bracket lfia that is fixed to the board and which has two spaced, downwardly directed legs lEb-lfiib between which a block We is pivoted by a cross pin l8. The upper end of each leg is biiurcated, as in Fig. therein and this end is pivoted on the block by a cross pin l8 that extends at a right angle to pin l8;

When the boards 8 and lb are disposed flatly against the base frame, their top surfaces will lie in the same horizontal plane. The hinge axis of the board it as established by the line of pivot points lZ -IZ lies in this plane, Therefore, when 5, and receives a block I the board I is adjusted to any of its different angular positions, the plane surfaces will intersect along the line of the hinge axis, The cross bar 1 substantially coincides with this hinge axis.

Mounted upon the cross bar 7 is a standard 20. This has a guide bearing 2| at its lower end which holds the standard rigid but permits it to be freely movable along the bar. If it should be desired, this bearing might be equipped with anti-friction rollers to insure freedom of movement without permitting looseness.

At its upper end, the standard is equipped with a bearing 22 in which a cross rod 23 is slidably contained for endwise movement. This cross rod is held parallel to the plane of board 8 and perpendicular to the direction of travel of the standard along bar 1.

At one end of the cross rod 23, a stylus 24 is vertically mounted for easy u and down adjustment, but without looseness, Likewise, at the opposite end of the cross arm, a marker 25 is mounted for up and down adjustment. The mode of mounting the stylus and the marker, and the manner of mounting the cross rod in the standard, and the standard on the cross rod 1, is such that any movement of the stylus along the board I0 up or down the board, causes a like travel of the marker along the board 8. The marker is sumciently heavy that it will move down and maintain marking contact with the paper, except when manually lifted.

In use of the device, the drawing from which the projection is to be made is secured by tacks or other means upon the board it; such a drawing being indicated by reference character D in Fig. Upon the board 8, a sheet of paper or the like, as designated at P, is fixed to receive the projection. The operator then with one hand grasps the stylus and with its point, traces the lines of the drawing. The stylus will move up or down as required to maintain contact with the drawing. As any line of the drawing is traced, the cross rod 23 may be moved endwise in its mounting and the standard may be caused to move along the bar 1. With the movements of the cross arm and standard, the marker will be caused to trace a line on the paper; it being understood that the marker may be a lead pencil or the like.

If the board [0 is placed horizontally; that is, in the same plane as the board 8, then the projection will be merely a full size reproduction of the drawing. However, if the board I 0 is swung upwardly to an angular position, as seen in Fig.

1, then the projection Will be in accordance with the angular disposition of the board.

The usual procedure is for the user to grasp the stylus with one hand and to assist in the use by using his other hand to move the standard along the rod 7.

In order that the user of the device may use the same hand which grasps the stylus, to lift the marker from the paper when it is desired that it should not make a mark, as in making adjustment of the device, I have pivotally fixed a lever upon the end of the cross arm which is adjacent the stylus with one end of this lever extended downwardly along the stylusand the other end extending upwardly somewhat above the pivot which is shown at 3!. This upper end of the lever is connected pivotally to one end of a horizontal link 32 which, at its other end, pivotally connects as at 33 with a bell crank lever as which is pivotally mounted on the cross rod 23 closely adjacent the marker, and having an arm engaged with a shoulder 35 on the upper end of the marker rod. By pressing the lower end of the lever 39 toward the stylus, the linkage described moves the bell crank in a manner whereby to efiect the slight lifting of the marker from engagement with the paper. Thus it is possible for the user of the device to grasp the stylus and with one finger engaging the lever 30, to move the stylus in any direction for tracing lines of the drawing, and to lift the marker from the paper at any time desired. As soon as holding pressure is released from the lever, the weight of the marker brings it into contact with the paper.

In Fig, 4, I have illustrated an alternative form of device in which, at top and bottom edges of both the boards 8 and Ill, rollers 49 are mounted, and it is shown that a strip of paper 4! is wound on rollers associated with the board 8 and extends across the board. Likewise, a drawing sheet 42 is wound on the rollers associated with on the strip 42,

It is anticipated that at least one of the brackets I i would be equipped at its pivoted end with a pointer 58 and that the adjacent surface of the bearing 5 or 6 would be marked, as at 5|, so that the angle of the board [0 relative to the board 8 could be readily set in sired angle of projection.

With the device so constructed, it is possible for a person inexperienced in drafting to make accurate projections at any designated angle of projection.

Further it is to be understood that by reversal of the marker and stylus, it would be possible to reverse the procedure so that plan or elevations might be made from a projected drawing.

Machines or devices of this kind might be made in various sizes and proportions other than shown without departing from the spirit of the invention.

Having thus described my invention, what I claim as new therein and desire to secure by Letters Patent is:

1. A drafting device comprising a pair of base boards each having a plane surface, disposed side by side and hingedly joined at adjacent edges for relative adjustment of the plane surfaces to difierent angular relationships between 180 and a bar extended along the hinge axis and fixed relative to one board, a standard mounted on and movable along the bar, a cross rod carried by the standard for endwise movement therein in a direction at a right angle to the direction of the said bar, a stylus mounted by the cross rod at one end for tracing the lines of a drawing applied to the plane surface of one board, and a marker carried by the other end of the cross rod to draw a projection of the traced drawing on the plane surface of the other boar 2. .A drafting device as in claim 1, wherein the stylus and the marker both are mounted on their respective ends of the cross rod for up and down movement for tracing the drawing and for draw ing the projection.

' 3. A drafting device as in claim 1, wherein the stylus and the marker both are mounted on their respective ends of the cross rod for up and down movement for tracing the drawing and for drawing the projection, means mounted at the stylus mounting end of the cross rod operable to lift the marker from the drawing surface.

4. A drafting device as in claim 1, wherein the accordance with the de- 5 Stylus and the marker both are mounted on their respective ends of the cross rod for up and down movement for tracing the drawing and for drawing the projection, a lever pivotaliy mounted at the stylus end of the cross rod, 2. bell crank lever mounted on the cross rod at the marker end and operatively connected with the marker for lifting it and a link operatively connecting the lever and bell crank.

JESSIE T. IVY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Warner et a1 Mar. 26, 1918 Farnum May 6, 1919