US26484A - Platform-scale - Google Patents

Description

- 3 Sheets-Sheet 1. -T. FAIRBANKS.

Platform Scales.

No. 26,484. Patented Dec. 20, 1859:

GRovNmPLAN" l 3 Sheets-Sheet 2.

T. FAIRBANKS.

Platform Scales.

PatentedY Dec, 20. 1859.

. 3 Sheets-Sheet 3. T. FAIRBANKS.

, Platform Scaies.

No. 26,484. Patented Dec. 2o, 1859.

#27H65 ses muy '2f/WM? .Mm /f/Wfw THADDEUS FAIRBANKS, OF

ST. JOHNSBURY, VERMONT.

PLATFORM-SCALE.

Specification of Letters Patent No.

To all whom it may concern.'

Be it known that I, THADDEUS FAIRBANKS, of St. Johnsbury, in the county of Caledonia and State of Vermont, have invented an Improvement in Platform- Scales for IVeighing Heavy Bodies; and I do hereby declare that the same is fully described and represented in the following specification and the accompanying drawings, of which- Figure l, denotes a ground plan of the framing of a platform and pit frame of a scale or weighing machine, the said figure exhibiting (by links, A, B, C and D) the general arrangement of the weighing levers by which the platform is supported. Fig. 2, is a side elevation of the platform. Fig. 3, a sectional view of the platform and its pit frame. Fig. 4, another sectional view, exhibiting the relative situations of the three levers A, B, C, and their knife edge bearings. Fig. 5, is a diagram illustrating the arrangement of the devices for supporting the lapped ends of the levers, A and B, and connecting them with the steelyard rod, Fig. 6, is a top view of the bottom bar of what is termed the yoke, while Fig. 7, is an underside view of the top bar of said yoke. Fig. 8, is an end view of the yoke and ex hibits in dotted lines the bearings and the bearing pivots of the lapping levers.

The nature of my invention consists principally, in a peculiar application and arrangement of a yoke, stirrup, pivots and bearings, whereby the lapped ends of the two multiplying and transmitting levers, A, and B, are supported and connected with the depending rod of the steelyard.

In the drawings, E, represents the plat-- form on which the article to be weighed is to be supported, F, being the surrounding or pit frame to which the levers, A, B, C, D, are suspended in the usual manner. The two levers, A, B, near their outer ends cross one another, one being made to project over the other as shown in Fig. 4t, wherein the lever, B, or a part thereof is represented as extending underneath the lever, A, the same also being exhibited in Figs. 5 and 8. At or near the end of the lever, A, two conical pivots, a, Z), are made to extend vertically in opposite directions from the said lever; while from the end of the lever, B, and in a vertical line with the pivots, a, o, another conical pivot, c, projects downward, the same being as shown in Figs. 4 and 5. The two levers, A, and B, extend into a yoke, G, which consists of a rectangular frame, whose upper and lower bars, d, e, at the centers of their 26,484, dated December 20, 1859.

inner surfaces are furnished with concave bearings or steps, f, g, for thereception of the pivots, a, and c. Furthermore, the rod, I, that extends downward from the steelyard is furnished at its lower end with a stirrup, whose foot or crossbar, z., is placed within the yoke, G, while its rods or prongs, z', z', pass upward through openings, 7c, lo, made through the bar, cl, of the yoke, these openings being large enough to allow the yoke to play freely without contact with the stirrup. Furthermore, the lower bar, It, of the stirrup is constructed with a hollow step or bearing, Z, for the reception of the pivot, b, which extends downward from the lever, A.

From the above, it will be seen that the yoke is not only supported by the pivot of the lever, A, but such yoke sustains that of the lever, B, the latter lever being supported by the stirrup or the pivot, l), resting in the bearing, Z, of the said stirrup. Also, that while all the pivots and bearings are in one vertical line, t-he yoke can play or move freely both up and down as well as laterally, as it may without friction against the stirrup.

By means of the yoke, the stirrup, the pivots, and dished or concave bearings applied and arranged together and with reference to the levers, A, B, and the rod, I, as described, I am able to obtain an advan tageous method of supporting the multiplying levers from the rod of the steelyard, such not only enabling' the levers to oscillate freely, but to transmit their power or pressure correctly to the steelyard during any of their oscillating movements.

Upon the steelyard rod, I, and over the upper crossbar of the yoke, I place a cap or bonnet, a2, to suitably cover or extend over the yoke and protect the pivotl bearing from either dust or water.

IVliat, therefore, I claim as my invention or improvement isl. The arrangement and application of the yoke stirrup, their concave steps or bearings and the pivots of the two multiplying and transmitting levers substantially as specified, the whole being for the purpose and to operate as described.

2. I also claim combining with the rod, I, and the yoke applied thereto as described, the cap or bonnet, a2, the saine being for the purpose as specified.

THADDEUS FAIRBANKS.

Iitnesses B. I-I. EDDY, F. P. HALE, Jr.

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