US819495A - Drafting instrument. - Google Patents

Description

N0. 819,495. PATENTED MAY 1, 190s. A. A. ALLEN.

DRAPTNG INSTRUISIIENT.

PPLIATI-GH FILED APB. 1905.

wfrflfssfs: wwf/fron ci.

ATTRNEYS UNITED STATES PATENT OFFICE.

RAFTNG INSTRUMENT.

Specification of Letters Patent.

Patented May 1, 1906.

Original application led duly '7,1904,Serisi No. 215.622. Divided and this application filed April 8, 1905. Serial No. 254,431.

To all whom it may concern:

Be it known that I, ALBERT ARTHUR AL- Y LEN, a citizen of the United States, and a resident of Ortonville, inthe county of Bigstone and State of Minnesota, have invented a new and Improved Drafting Instrument, of which the following is a full, clear, and exact description, this being a division of the a piication or Letters Patent of the United tetes, Serial No. 215,622, iiled by me July 7, 1904.

The object of the invention is to provide a new and improved draftin instrument, more especiaiiy .designed for t e use of tieners', plumbers, and other mechanics in laying ont the blanks for formin elbows, Ts, and other articles of sheet meta and like VInateriai.

The invention consists of Ynovei features and arts and combinations of the saine, Vas will Ve more fully described hereinafter and then pointed out in the claims.

A practical embodiment of the invention is represented in the accompanying drawings, forming a part of this specication, in which similar characters of reference indicate corres onding parts in all the views.

igure 1 is a side elevation of the improvement. Fig. 2 is a sectional plan view of the same on the line 2 2 of Fig. 1, and Fi 3 is a transverse section of the same on the ine 3 3 'of Fig. 1. The dividerA (shown in the accompanying drawings) is arranged for obtaining on the diameter of a tubular body une nelly-spaced diametrical ordinate points. his divider may be used in connection with a peripheral divider of any suitable or improved construction-such, for instance, as shown and described in the Letters Patent above referred to and arran ed for obtaining ordinate points spaced equa distances apart and dividing the peri hery of a tubular body into equal parts. y drawing from these points it is evident that curved coordinates are ob-V tained to permit of convenientiy and quickly drawing the desired curve.

The divider A is' constructed in detail as follows: A plurality of spacing-bars C, C', C, and C3 are arranged parallel to each other, the bars C and Cz bein the end bars, the bar C the middle bar, an the bars C the intermediate bars, which latter and the middle bar C5 are mounted to slide in bearings D,

ivotally connected With the outer ends of inks or lazy-tongs E, carryingFat the middle of some of the links bearings mounted to slide on a cross-rod G. The middle spacingbar C3 is secured at H to the rod G, while the intermediate bars C have bearingsv H slidabiy engaging the rod G. The end links or lazy-tongs E are connected by pivots I and I' with bearings H2 and H3, slidably en aging the rod G and ri idly carrying the en spacing-bars C and 2. The pivots l and I' are in the form of clampin -screws to allow the o erator to screw up tie ends thereof and c amp the fixed parts in position to heid the divider against movement after the desired adjustment of the parts is made, as hereinafter more fully described. l'

Y The links or lazy-tongs E are graduated in sizethat is they graduaiiy increase in size i from the ends toward the middle, as plainly indicated in Fig. l-the links being so graduated in size that the spacing-bars C, C', and

,C2 stand in such relation to each other that they reduce diametrical ordinate points. By a justing the lazy-tongs E so that the points'of the end spacing-bars C" and C2 are a distance apart corresponding to the diameter of the tubular body the spacingbars C and C3, located between the end s seing-bars C and C2, are spaced unequal istances from each other, and the points marked on the diameter corres ending to the said intermediate spacing ars are diametrical ordinate points. It is understood that lines drawn through the ordinate points at right angles to thc diameter divide the circumference of the circle for the said diameter into equal spaces.

By reference to Figs. 1 and 3 it will be seen that the spacing-bars C, C', C, and G3 are extended beyond the bearings D to form extensions C, which are bent inwardly toward the extension C5 of the middle spacin -bar C3, it being, however, understood that t e said extensions are so bent that the distance between the points at the extension ends will be less than the distance between the points at the other ends of the bars to permit of using the extensions for small diameters the same as the other ends of the spacing-bars, which are used for large diameters.

in order to lav out the blanks for an elbow, for instance, t e operator opens the lazytongs E so that the distance between the end spacing-bars C and C2 corresponds to the diameter of the tubular body, and then the operator marks the diametrical ordinate points on the blank sheet of tin or other sheet metal, these points corresponding to the intermediatc spacing-bars. The operator now iigures out the length of the periphery of the tubs IIO lar body and extends the same at right angles to the diameter laid out on the sheet between the end spacing-bars C and C, as

above explained, and then by means of a suitable peripheral divider arranged for obtaining ordinate points s aced equal distance a art the o erator divi es the periphery of tlie tubular ody into equal parts and marks the peripheral points' on the sheet. The coordinate lines are then dra-Wn from both the diametrical and peripheral points, the point of intersection of the said lines giving the curve coordinate for forming the necessary curve. The operator now (mis along the line of this curve and then bendsttlie two pieces of the blank into a tubular shape, sc that the two pieces peripherally :[it at :the mite r]oint along the curved edgesr as will be readily understood.

; For forming Ts and. other .anticles the operator` proceeds in substaiittiallly the Same manner as above desciribed.

It is understood that the instrument can be readily employed in laying out various 'quickly set the divider other curves required inthe formation of tubular jointed bodies. B the use of the device the mechanic Lnee s no patterns to be ded by; but he can tto a given diameter for the purpose above described.

Having thus descril )ed ,my invention, I

Claim as new and desi] re to 'secure by Letters Patent- 1, iin instrument .fol 1 Obtaining curved ooordiiiates, com rising a diameter-divider 35 having Spacingars, a cross-bar mounted o slide in bearings on the 1 said spacing-bars, and connected links slidal il oonnected with the said spacing-bars and e said cross-bar.

2, An instrument i or obtaining curved eoordinates, comprising: a diameter divider having,` s seing-bars, a- Gross-bar mounted toslide in earings 0n ithe said spacing-bars connected links siidsbly Connected wiih'ih Said Spa@ hars and tliesaid cross-bar, and a 4 5 fastnmg evice for holding the parts against movement.

3. An instrument for obtaining curved coordinates, epmprising a diameter-divider having spacing-bars arranged parallel and 5o having reducing extensions at one end, a cross-bar mounted to slide in bearings on the said spacing-bars, and connected links slidabi connected with the said spacing-bars an the said cross-bar.

In testimony whereof I have signed my name to this specification in the presence of twosubscribin Witnesses.

AL ERT ARTHUR ALL EN.

Witnesses:

Trios. F. WILSON,

J. WEBER.

Images