US340011A - Molecular pivot-balance - Google Patents

Description

(No Model.)

A. SPRINGER.

muLEcULAR PIVOT BALANGE.

"No. 340,011. Patented Apr. 13 1886.

JNVENTOR ATTORNEY N. PETERS. Fbolo-Mhcgnpiwr. Washingkxl, a c.

UNrrET) STATES PATENT OFFICE.

ALFRED SPRINGER, OF CINCINNATI, OHIO.

MOLECULAR PIVOT-BALANCE.

= -PECIFICATION forming part of Letters Patent No. 340.011, dated April 13, 1836.

Application filed April 27, 1885. Serial No. 103,511. (X model.)

To aZZ whom it may concern.-

3e it known that I, ALFRED SPRINGER, a citizen of the United States, residing at Cincinnati, Ohio, have invented new and useful Improvements in Molecular Pivot-Balances, of which the following is a specification.

My invention relates to that class of bal unces in which one or more leverage multiplior levers and introduce a serious error in the readings of the markinglever, which error in creases with the amount of load.

The object of my invention is to provide a remedy for this difliculty, whereby the effect of the depression of the main beam or its pivot maybe counteracted and the scale-readings remain unimpaired.

My invention will be more clearly appreheaded by reference to the accompanyi ngdrawings, in which Figure l is perspective view of a simple beanrscalc to which the auxiliary beam or lever is attached for scale-reading. Fig. 2 is a diagram of the same scale, showing the relation of the lovers and their pivotal connections. Fig. 3 is a diagram representing a torsional pivot stretched between its holdingabutments. with cross-section of the scale-beam attached thereto and indicating the sagging effect of weight upon the beam. Fig. at is a diagram in the plane of the main and auxiliary beams, showing the abnormal deflection of the auxiliary beam or pointer due to the abnormal depression of the main beam. Fig.' 5 is a diagramof the same parts,showing the effect of the same as corrected by my improvement. Fig. 6 is a detailed side view and crosssectioiii of the adjusting mechanism for shifting the distance ofthe terminal pivot from the center of rotation upon the main beam.

Referring now to the drawings, A represents the main scalebeam; B, the supporting-pedestal; b I), the abutments between which the fulcrum-pivot is stretched; P, the fulcrumpivot; E E, the terminal torsion frames, (embodying torsional pivots pp',) by which the scale-pans FF are suspended; G, the any iliary lever, used as an indicating-pointer and moving upon the graduated arcplate D; E, the torsion-frame connecting the main beam with the auxiliary beam, including the torsionpivots p andp, and E represents the torsionl'rame embodying the torsion-pivotp, constituting the fulcrum of the auxiliary lever or pointer O. The torsion-frame E is mounted upon or hung from suitable supports, ff, attached to the general frame or con taining-case of the balance. The scale-beam A is provided with a central standard, S, and an adjustable weight, N, serving as a counterpoise to the molecular resistance of the pivots, and the auxiliarybeam C is also furnished with a vertical standard, .9, rising above its i'nlcrunr pivot, and an adjustable weight, w, acting in conjunction with the counterpoise \V. The construction of thescalc as thus shown is fully detailed in other patents already granted to me and in ayi piications now pending, and need not be further described here.

The diilicnlty to which my present invention is directed is partially illustrated in Fig. 3, in which it will be obvious that a weightplaced upon the beam A-that is, a load placed in the scale-pans of the beam-tends to stretch the fulcrunrpivot and depress it and the beam into the positions indicated by dotted lines, the effect of which upon the lever G is indicated in Fig. #l. The scalebeam A, as shown in said figure, being depressed into the position indicated by dotted lines, the auxiliary lever or pointer G will be drawn down into the diagonal position, also indicated by dotted lines, and the are which would in such case be traversed by the pointer G represents the amount of error upon the graduated arc-plate D. This error I overcome by increasing the length of the beam from its fulcrum to the end opposite the secondary lever-connection-that is, atthe right hand end indicated in the dra\viugsthe effect of which is to increase the statical moment of the weight placed at or suspended from such end, thereby tending to elevate the opposite end of the beam just sufficiently to overcome the tendency referred to.

Thus, referring to Fig. 5, the fulcrum-pivot P being depressed to the position indicated in the dotted lines, instead of remaining parallcl to its former position, is thrown into the inclined position shown by thedotted Iinesiu which the left-hand end of the beam is elevated just sufiiciently to counteract the elfect of the change of position of the fulcrum.

In carrying out my invention mechanically, it may obviously be applied in all classes of balances,whatever may be their construction, and also by various means adapted to each particular case.

In order to secure the necessary elongation of the beannas described. I have found it-eonvenient to use the device indicated in Fig. (i, in which the terminal pivot p is passed th rough and secured in a sliding block. 1'. secuiel beneat h and around the beam, having an upward projection. threaded upon an adjustingscrew, 72, passing through lugs g 9. arranged upon the upper side of the bcam. By means of an adjusting device ofthis nature the beam may be properly lengthened alter construction as part of the general adjustment of the balance, and it is found that when so made. in proper relation to the elastic strength of the pivot as agaimt vertical deflection. the pro-. portionate increase in the statical momentof the weight or load main ains a constant and uniform correspondence with the vertical deflection of the pivot, and the scale action is perfect for all loads within its predetermined capacity.

The temporary adjustability of the length of the beam isa matter of convenience merely, and the length may be permanently fixed in the original construct-ion, if preferred. In steelyard-balances the result is attained in the same manner by adding to the length of the beam at the load-suspension end, so as to render the fulcrum length slightly in excess of the unit of leverage multiplication. The same result may be attained by shifting the position of the fulcrum-pivot, and such is within the spirit of my invention, but is far less convenient practically.

I claim as my invention. and desire to secure by Letters Patent of the United States 1. In a molecular pivot-balance embodying one or more leverage multiplications, the combination,with the balance-beam lengthened at its load-suspension end beyond the normal unit of leverage multiplicatiomof an auxiliary multiplying beam or marker independently fulcrumed and connected with the main beam by a torsional t'rame,substantially as described.

2. In a molecular pivot-balance, the combi- .nation of a balance-beam having a torsional fulcrum. an auxiliary multiplying beam or marker independently fulcrumed. a torsional pivot-connection between said beams, and a horizontally adjustable \veiglitesupport upon the balance-beam at the end opposite its connection with the auxiliary beam, substantially Witnesses:

L. M. Hosea, ABRAM MAY.

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