US276701A - Postal scale - Google Patents

Description

(No Model.) 3 Sheets-Sheet 1.

J. P. MILLER.

POSTAL SCALES.

No. 276,701. Patented May l, 1883.

3 Sh.eets-Sheet 2.

(No Model.)

J. F. MILLER.

POSTAL SCALES.

Patented May 1, 1888.

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J. P. MILLER.

POSTAL SCALES.

No. 276,701. Patented May 1,1883.

UNITED STATES PATENT OFFICE.

J. FRANK MILLER, OF OAKLAND, CALIFORNIA.

POSTAL SCALE.

SPECIFICATION forming part of Letters Patent No. 276,701, dated May 1, 1888.

Application filed December 1, 18873.

To all whom it may concern:

Be it known that I, J. FRANK MILLER, of Oakland, county of Alameda, State of California, have invented an Improved Postal Scale; and I hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to an index or self-registering balance-scale, which is especially intended for postal or other similar purposes; and it consists of a series of graduated weights suitably supported, so as to be lifted consecutively and in a manner to counteract oscillation by means of a lever-arm, which has the weight-supporting pan upon its outer end, so that when it is raised it will lift the weights successively from their support as it moves. A curved graduated scale is fixed so that an index-pointer upon the end of the lever will indicate the weight or its equivalentpostage the moment the letter or other object is placed upon the pan; or the pointer may be fixed and the graduated are made movable.

Referring to the accompanying drawings for a more complete explanation of my invention, Figure l is an isometrical view of my scale. Fig. 2, Sheet 2, is a vertical section taken longitudinally to show the relative position of the arms, weights, and index. cation.

A is a base having a vertical standard, B, the top of which is cut away or so formed as to receive and support the knife-edge bearings U of the lever D, as shown. The base and upright may be formed in one piece, the former being heavy enough to insure steadiness, and a small spiritlevel, Q, is fixed in it, so that it may be set in the proper position at any time.

Fig. 3 is a modifi- Upon the short end of the lever D the open bar E is suspended by anti-frictional or knifeedged supports F, and its lower end is connected with the lower partof the standard B by a loose link, I), which maintains it in a vertical position and steadies it, while allowing it to move freely up and down with the lever D. Upon the top of this bar E is supported the scale pan or platform G. The lever D is preferably made with .two parallel arms a short distance apart, and curving downward in an are, having the convex side uppermost. The upper edges of these arms are notched, as shown at a, to receive the weights, as will be (No model.)

hereinafter described. The outer ends are united and steadied by a bar, and weighted sufficiently to counterbalance the pan.

Two arms, H, are secured to the standard I; at the top, and they extend in the same direction with the long arm of the lever D, so that these arms may move up and down between them. 'In the present case I have shown the stationary arms II formed in a curve, having the concave side uppermost, as this gives a convenient form of support for the weights. It will be manifest, however, that the same result can be obtained by supporting the weights in other ways, so as tobe lifted successively. It will be seen that when the pan is depressed the curved arms of the lever will rise between the arms H. The arms H are notched upon their upper surface at a, and weights I have pins or armsJ projecting from each side to rest in these notches, and thus suspend theweights, which are calculated so as to decrease gradually in size from the inner to the outer end of the arms II. When the pan G is loaded the arms D rise between the arms H, and the notches a upon their upper edges successively lift the weights I from the arms H, so that they are suspended upon the convex back of the lever.

K is a circular arc projectingupward from the end of D,and having the fulcrum G of the lever D as its center of curvature. This are is graduated to half-ounces, and marked with figures representing the sought-for amount of postage in separate columns. The are K may be fixed to the base-plate and remain stationary, while the indicator moves. \Vheu constructed in this manner, It is an indicator firmly attached to the ends of the movable arms D, so as to move over the graduated are when a weight is placed in the pan; but when the arc K moves, as shown in the present case, the indicator is fixed to the base or other stationary support.

The operation will then be as follows: The scale is approximately leveled by means of the spirit-level in the base, and the indicator will stand at O of the index. When any small weight less than one-half an ounce is placed in the pan the indicator marks that amount; but the first weight will not be lifted until the weight in the pan exceeds one-halt an ounce and is less than one ounce, when the indicator immediately moves above the half-ounce line and rests below the ounce-line. When the Weight is one ounce the indicator rests on the ounce-mark. In this manner the exact amount of postage due is instantly shown. Vhen any weight is placed upon the pan its downward motion is resisted by an increasing number of weights, as they are picked up by the movable lever-arms I), while the upward motion is resisted by the successive dropping of the weights. In this manner oscillation is soon stopped.

In the present case I have shown the arms of the lever and those supporting the weights as made in the curve of a spiral, with notches uniformly increasing; in distance from the fulerum. The index is also of uniform graduation; but it will be seen that a great variety of curves or even right lines might be employed with the same results. The graduated arc may be fixed to the end of the movable arm QWLEIOE and the indicator to the side of the fixed arm, so that the smaller numbers will be shown at the top for greater convenience in readin One form is shown at Fig. 3, in which the weights are made with circular openings, and are fitted upon a cone, the base of which rests upon the plate A, while it curves upward between the arms 1), so that as the arms rise they will lift the weights successively.

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

In a balance-scale, the lever-arms 1), moving about fulerums U, in combination with the graded weights I, which are successively raised or deposited by the movement of the arms, substantially as herein described.

In witness whereof I hereunto set my hand.

J. FRANK MILLER.

Witnesses:

H. CLAY llIlLLER, JOHNA. SAMPSON.

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