US2452484A - Ellipsograph - Google Patents

Description

Oct. 26, 1948.

K. B. .NOBLE 2,452,484

ELLIPSOGRAPH Filed April l5, 1944 w33 36 236/7 646` .a5 r5.2

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Patented Oct. 26, 1948 UNITED STATES lPATENT OFFICE.

l ELLIPsoGRAPH Kenneth B. Noble, Hartford, Conn.

Application April 15, 1944, Serial No. 531,149

4 Claims. 1 This invention `relates to improvements ellipsographs.

One object of this invention is to provide an improved. ellipsograph of simple construction inl whereby ellipses can be completely scribed without employing any supplemental devi-ce.

Another Iobject of this invention is to provide an improved ellipsograph formed of simple elements readily manufactured to produce an eiiicient construction at moderate cost.

With the above and other dbjects in view; as will appear to those skilled in the art `from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art.

In the accompanying drawings forming 'part of the present disclosure, in which certainways of carrying out the invention are shown for illustrative purposes:

Fig. 1 is a perspective view of an ellipsograph made in accordance with the present invention;

Fig. 2l is a top plan View of the track-construction portion of the ellipsograph, with one of the track-members shown in detached but adjacent position;

Fig. 3 is a sectional view on an enlarged scale, taken on line 3-3 of Fig. 2;

Fig. 4 is a top plan view of the scriber-bar construction;

Fig. 5 is a side elevation of a frag-mental endportion yof Fig. 4;

Fig. 6 is a front elevation of one of the scriber- I bar pivot-members;

Fig. 7 is a perspective view of the slide of Fig. 6; Fig. 8 is a perspective View of the scriber-hold- Fig. 9 is a front elevation yof a pencil-scriber;

Fig. 10 is a side elevation of a pen-scriber;

Fig. 11 is a side elevation ofthe detached trackmember forming the upper part of Fig. 2;

Fig. l2 is an end view of Fig. 11;

Fig. 13 is a front elevation of the track-member shown in Fig. 2;

Fig. 14 is a view similar to Fig. 13 of a Ashorter track-member; and

Fig. 15 is a view similar to Fig. 13 of a longer track-member adapted to be removably secured to the center-hub in three different longitudinal positions.

Referring to the drawings, the ellipsograph 2|) includes a relatively-fixed track-construction or -means 2| and a relatively-movable scriber-c-onstruction or -means 22. The track-construction 2| includes a center-hub 23 having transverse slots 24 and 25 extending entirely therealoss at horizontal right angles to one another, each of said slots being of rectangular cross-sectional form of the same width and depth and of a size to have a neat sliding-fit with any of the track-members or -bars 26, 21 and 28. Spring-pressed latches or locks 29, 30, 3| and 32 serve to removably secure the track-bars in their proper positions in the slots 24 and 25 of the center-hub 23.

Each of the four latches includes a latch-bolt 33 (Fig. 3) longitudinally slidable in a 'hole 34 in the center-hub 23 and normally pressed inward by a c-oil-spring 35 to cause the inner end 36 of the bolt to be engaged in one of the latching-recesses or -sockets 31 of the track-bars, the spring 35 having vone of its ends pressing against the flange kor washer 38 on the bolt, and having its other end pressing againstl the washer 39, which is i'lxedly secured in an annular shallow recess 4|] in the center-hub 23. The shank 4| of the latch-bolt 33 extends through a latchoperating member 42 which is freely -pivoted thereon, and is held in properly-adjusted position [by suitable adjustment of a nut 43 upon the threaded end of the shank 4|. A slot 44 in the end of the latch-bolt 33 serves to permit of holding the bolt against rotation by a screw driver while the nut 43 is being forcibly screwed onto its desired adjusted position.

The latch-bolt 33 can be operated to release its engagement with any of the track-members by engaging the upper end-portion 45 of the latch-operating member 42 (Fig. 3) with a finger or fingernail and pressing it to swing it downward toward the broken-line position shown in Fig. 3, to cause the lower end-portion 46 of the operating-member 42 to ride along the cylindrical surface 41 of the center-hub 23, to thus produce a camming action to force the latch-bolt 33 to move longitudinally of itself -outward against the action of the spring 35 -untl the inner end 36 of .the latch-bolt 33 is drawn back at least 'as far as the side-face 48 of the track-bar in which the latching-recess 31 is formed, whereupon the tra-ck-bar can be withdrawn from its location in the slot 24 or slot 25 in which it may be located 'in the center-hub 23. The combined action lof the spring 35 and the cam-surface 41 restores the parts 4'2 and 33 to the original locking position.

T-o replace a track-bar in its position in a slot in the center-hub 23, as for example in the case of the track-bar 26 shown in Fig. 2, it can be moved longitudinally from its position shown in Fig. 2 into the slot 24 until the cam-face 49 of the track-bar engages the end 33 of the latch- 'bolt 33 of the latch 29, to thus force the end 36 backward as far as the face 48 of the track-bar 26, thus permitting the track-bar 26 to be pushed longitudinally inward to its proper position, whereupon the bolt-end 36 is snapped automatically into the recess 31 by the spring 35. Of course, the track-bar 26 can be inserted in its latched or locked position by movement in any direction as, for example, bymoving it transversely of the slot 24, but inthis case it is necessary to operate the latch-operating member 42 by pressing it with a iinger, as previously described, in order to retract the latch-bolt 33.

The track-bar 21 (Figs. 2 and 13) has latching-recesses 31 in its opposite sides to be engaged by the latches 30 and 32 when the track-bar 21 is moved into the slot 25 of the center-hub 23 while the latch-operating members 42 are held in unlatching position, after which they are moved to latching position to permit the latch-bolt ends 36 to engage in the latching-recesses 31, as previously described with regard to track-bar 26. The track-bar 28 is identical with track-bar 26 and, therefore, is removable and replaceable in its latched position in the center-hub in the same manner as previously described concerning the track-bar 26. j

It will be noted that the track-bar 21 extends horizontally clear across the center-hub 23, whereas the two track- bars 26 and 28 when in their assembled position, as in Fig, 1, will abut against the opposite side-faces of the track-bar 21.

Each of the track- bars 26 and 28 is provided with a track-way portion 58 which, together with the track-way slots formed inthe track-bar 21, together constitute one track-way 52 of the ellipsograph. Another track-way 53 in the trackbar 21 forms the other track-way extending at right angles to the iirst track-way 52. Each track- bar 26 and 28 has a recess 54 in which is secured a footor support-memberl 55 which may, for example, be of soft rubber or may be a needlepoint member. And the track-member 21 has two of these feet 55 (Fig. 13) adjacent its opposite ends. The feet 55 are of a length to support the track-construction portion 2| of the ellipsograph upon four feet 55, with the bottom-surface of the center-hub 23 preferably spaced upfsornewhat from the surface on which the ellipse is to be able scriber or scribing-member such, for ex` ample, as the pencil-scriber 58 shown in Fig .9 or the pen-scriber 68 shown in Figi 10.

' Each pivot-slide 51 includes a slide-bar or slide 6| shaped to have a neat sliding-fit in the various trackways. A pivot-disk 62 is connected to the slide-bar 6| by means of a` screw 63 threaded into the slide and having its countersunk head 64 serving to pivot the disk 82 relatively to the slide-bar 6| A cap-disk 65 is secured to the disk 62 by the screws 66. A recess 61, which extends entirely across the lower face of the cap-disk 65, in conjunction with the upper face of the disk 62 constitutes a channel or passage through which the scriber-bar 56 is slidable for adjustment, it being secured in any desired position of adjustment by means of the screw 68 mounted in the disk 65 by screwing it downward to clamp the scriber-bar 56 in its desired position of adjustment. A recess or clitaway-portion 65 (Fig. 4)

in the 'cap-disk 65' permits of visual observation of the graduations of the scale on the upper face of the scriber-bar 56, the rear face 18 of the slot 69 intersecting the pivot-center of the scriber-bar 56 and the disks 65 and 62, thus serving as the points of observation in determining the distance between the pivots of the two pivot-slides 51. The scriberholder or -head 58 has a cross-slot 1| in which one end of the scrber-bar 56 is clamped in position by means of a screw 12. The scriber-holder 58 has a cylindrical hole 13 which extends vertically downward, and in which the cylindrical surface 14 of the pencil-scriber 58, and the cylindrical surface 15 of the pen-scriber 6D have a neat sliding-fit. When the pen-scriber 68 is to be used, the slot 16 provides a clearance-way to accommodate the shank 11 of the adjustingscrew 18. If desired, the scriber-member used may iioat by sliding up and down in the cylindrical hole 13, or it may be iirmly secured in a given position therein by means of a clampingscrew 19.

With the distance relations between the center of the hole 13 of the scriber-holder and the pivotcenter of each of the pivot-slides 51 suitable to scribe a given ellipse, in accordance with wellknown principles, the clamping-screws 68 are clamped down to hold the pivot-slides 51 in the desired selected positional relations with regard to the scriber-bar 56. Assuming the size of the ellipse to be drawn tobe large enough so .that as the scriber, such, for example, as the pencilscriber 53, can pass beyond the ends of all the track-bars, it is merely necessary to move the scriber-member in a direction transverse of the scriber-bar 56 to scribe an ellipse, the pivotslide 51 mounted in the trackway 52 moving back and forth along the trackway while the other pivot-slide 51 moves back and forth along the other trackway 53 in a well-known way. If, however, the size of the ellipse to be scribed is such that the track- bars 26 and 28 are too long to permit of the passage of the scriber past these track-bars, then before the scriber reaches a position near the bar 26, the latch 28 is actuated to release the bar 26, which is thereupon removed and the scriber is continued inits elliptical path until it passes beyond the place which had been occupied by the bar 26, whereupon the latter is replaced in its original position in the center-hub 23 in a manner previously described, and the scriber is continued in its elliptical rotation past the right end of the track-bar 21, whereupon the track-bar 28 is removed from its position in the center-hub 23 in the same fashion as previously described concerning the trackbar 26, until the scriber has been caused to travel past the position previously occupied by the trackbar 28, whereupon the latter is vreplaced in its position shown in Fig. 1 and the scriber is continued in its rotation until it completes the ellipse at the position from which it originally started.

If it happens that the track-bar 21 is too long to permit of the scribing of a given desired ellipse, then a shorter track-bar, such as the track-bar 88 of Fig. 14 is substituted in place of the trackbar 21. The track-bar 8| of Fig. 15 could be employed in place of either of the track-bars 21 or 88 of Figs. 13 and 14. If track-bar 8| of Fig. 15 were in position in the center-hub 23 in place of the track-bar 21, and it were desired to draw an ellipse smaller than could be drawn with the track-bar 21 in place, for example, then it would not be necessary to remove the track-bar 8| to substitute the track-bar 80 of Fig. 14 in place thereof, but it would only be necessary to unlatch the two latches 30 and 32 and shift the track-bar 8| longitudinally of itself to bring the locking-holes 3l' adjacent one of its ends in position to be latched or locked by the latches 3D and 32, in which position the scriber could be moved past that end of-the track-bar 8|. When the scriber-member had been swung around to near the other end of the track-bar 8|, then the track-bar 8| could again be unlatched and slid back longitudinally of itself in the opposite direction to bring the holes 31 adjacent such other end of the bar in latching position with the latches 3|! and 32, whereupon the scriber could be passed beyond this end of the bar 8| to make the ellipse in the manner more fully previously described.

In making ellipses with any of the constructions previously described, it will be noted that the outside-ends of all track-bars are provided with slots 82 which extend downwardly through the outer end-portion of each outer end of each track-member, to provide means by which the eye may readily align the track-ways with the pair of cross-lines customarily drawn by draftsmen, which lines pass through the center of the ellipse that is to be drawn.

The cross-sectional contour of the track-way is free of sharp edges and with the distance between the outer edges of the track-way, smaller than the maximum distance across the inner portion of the track-way, thus providing a smooth track-way slot which will hold the slides 6| from rising up out of the slots and also, due to the absence of sharp edges, avoiding any binding action,` thus bringing about very smooth action in the scribing of the ellipse with consequent perfection and speed of drawing of the latter. The track-bars are preferably made by extruding or drawing them to nished cross-sectional shape and size, thus making the shape and size of the trackway absolutely uniform. They can be satisfactorily extruded or drawn from brass, for example.

While the particular scribing means illustrated and described heretofore consists of means for drawing ellipses by pencil or ink, it will be appreciated that any suitable scribing-means may be employed with this device, such as gasket cutters, glass cutters, or other instruments, to mark or cut shapes in the form of an ellipse.

One can readily acquire sufcient skill in the removal and replacement ci the track- bars 26 and 28 so that an ellipse can be scribed quickly in a continuous motion and in one uninterrupted line to completion.

The invention may be carried out in other specic ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

1. An ellipsograph including: a center hub; track-members forming track-means which is provided with two trackways extending transversely of one another; at least one of said trackmembers being removably securable to said center hub by means of a latch which is spring-pressed to latched position and which is provided with an operating-member extending upwardly above the top of the ellipsograph adjacent said operating member; and scribing means including slides slidable in said trackways for scribing an ellipse.

2. An ellipsograph including: a center hub; track-members forming track-means which is provided with two trackways extending transversely of one another; at least one of said trackmembers being removably securable to said center hub by a latch having an operating member extending upwardly above the top of the ellipsograph adjacent said operating-member; and scribing means including slides slidable in said trackways for scribing an ellipse.

3. An ellipsograph including: a center hub; track-members forming track-means which is provided with two trackways extending transversely of one another; at least one of said trackmembers being removably securable to said center hub by means of a latch which is spring-pressed to latched position; said removable track-member having a cam-face adjacent one end for forcing the latch back against the action of the spring; and scribing means including slides slidable in said trackways for scribing an ellipse.

4. An ellipsograph including: a center-hub; a first track-member provided with a rst trackway and with a plurality of spaced-apart trackway slots extending transversely of said first trackway and being removably securable to said center-hub in diierent longitudinal positions; second and third track-members removably securable to said center-hub at opposite sides of said first track-member and providing a second trackway extending transversely of said rst trackway; one of said trackway-slots being in alignment with said second trackway, in each of the said different longitudinal positions of said track members forming track-means which is first track-member; and scribing means including slides slidable in said trackways for scribing an ellipse.

KENNETH B. NOBLE.

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

UNITED STATES PATENTS Number Name Date 246,174 McC-omb Aug. 23, 1881 302,247 Harwood July 22, 1884 932,768 Dexter Aug. 31, 1909 1,029,515 Schreiber June 11, 1912 2,326,412 Taylor Aug. l0, 1943 FOREIGN PATENTS Number Country Date 49,611 Switzerland Sept. 14, 1909 182,479 Germany Mar. 22, 1907

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