US375520A

US375520A - Weighing-scale

Info

Publication number: US375520A
Authority: US
Publication date: 1887-12-27
Anticipated expiration: 1904-12-27

Description

(No Model.) 2 Sheets-Sheet 1.

F. S. WASHBURN.

WEIGHING SCALE.

No. 375,520. Patented Dec. 27, 1887.

(No ModeL) 2Sheets-Sheet 2.

Y I. s. WASHBURN.

WBIGHING SCALE.

No. 375,520. Patented Dec. 27, 1887.

I IlIlllllllllllllllll/lfill UNITED STATES;

PATENT OFFICE.

FRANK s. WASHBURN, or CHICAGO, ILLINOIS.

WEIGHING-SCALE.

SPECIFICATION forming part of Letters Patent No. 375,520, dated December 27, 1887.

Application filed June 4, 1887.

T all'whom it may concern:

Be it known that I, FRANK S. WAsHBURN, residing at Chicago, in the county of Cook and State of Illinois, and a citizen of the United States, have invented certain new and useful.

Improvements in \Veighing-Scales, of which the following is a specification, reference being bad to the accompanying drawings,in which Figure 1 is aside elevation of a scale-beam with my improvements attached; Fig, 2, a side elevation of the outer end of the long arm of the scale-beam; Fig. 3, an end view of the same part; Fig. 4., a longitudinal vertical section of the devices added for preventing vibrations and for registering weights; Fig. 5, an end view with the short arm of the scale- 1 beam in section, showing the manner of forming and connecting the yoke to the scale-beam; Fig. 6, a plan view of the liquid-cylinder.

4 The object of this invention is to attach a .device to a platform-scale, so that moving cars or vehicles can be weighed while in motion or without stopping them; and its nature consists in the improvements hereinafter described and claimed as new.

In the drawings, Aindicates the beam-frame of an ordinary platform-scale; B, the scalebeam; 0, the poise; D, the hanger; E, rod connecting the beam with the platform-levers; F, regulator; G, counter-balance; II, liquidcylinder; H, diaphragm-ring with bridge; I,

supports for the cylinder; J, vibration-regulator; K, hangers; L, hand-wheel and shaft for operating the regulator J; M, overflow- 5 receptacle; a, eccentric or scroll groove in the regulator J; 1), pin on scale beam passing into or through the groove a; a, yoke or saddle; d, knife-edge on the upper plate of the 1 yoke; d, point on the upper end of the rod f; 0 e, set-screw for locking the rod f to the yoke;

. f, rod connecting the scale-beam with the liquid-cylinder; g, turn-buckle or sleeve-nut; h, adj usting-collars with set-screws; i, diaphragmplate; j, diaphragm; k, liquid-reservoir; Z,

5 bent tube; m,stop-cocks; n,scale-plate, and 0 glass tube.

. The parts indicated by the letters A, B, O,

l D, E, F, and G are or may be of the usual construction, and the rod E connects the scalesolbeam with the usual system of levers, upon which the platform is supported in the ordi- Serial No. 240,311. (No model.)

nary manner. The outer or long arm of the lever scale-beam is provided with a pin, 1),

- near its end,w hich engages with the curved or scroll slot in the regulator J, which pin is directly beneath the shaft L, so that the vibrations of the pin do not cause a tendency to turn or rotate the regulator J. As shown in Fig. 1, the end of the beam is at its highest point, while the rotation of the scroll-disk to the limit of the slot places it in its lowest position. The slot must be large enough to give the pin a sufficient play to permit of accurate weighing, and the pin b may be a single projecting pin,or it maybe provided with an antifriction roller, if desired. This arrangement is important, as it permits of the scale-beam being adjusted to give the diaphragm of the liquidcylinder a proper position, and prevents vibrations of a sufficient length or range to communicatedisturbing vibrations to the liquid, which might otherwise be caused by the sudden increase or decrease of the load and by the running on and off of moving cars or vehicles.

The short arm of the lever scale-beam is' provided in the form shown with a slight extension to adapt it to receive the yoke c, which is the best mode of connecting the beam with the diaphragm of the liquid-cylinder known to me. This end of the short arm of the beam is formed as shown in cross-section at Fig. 5- that is, with a conical hole on the under side, into which the point (1 enters. The yoke c is preferably made in the form shown in said Fig. 5-that is, with two crossplates and connecting-rods. The upper cross-plate is provided with a knife-edged projection, d, which rests upon the scale-beam, and the lower plate is provided with a set-screw, e, by which the rod f can be lowered, so as to attach it, and then raised into position to insert the point d in the corresponding hole in the beam B. This construction of the yoke 0 gives it the proper movement, and at the same time retains it in position on the beam.

The connecting-rod f is preferably made in two parts connected by the turn-buckle or sleeve 9, the screw-threads being right and left, so that the length of the rod may be vavaried and adjusted. The rod is also provided with adjustable collars h on opposite sides of ICO the bridge orcross-bar H, which will prevent the undue straining of the diaphragm by reason of any accident or sudden movement, because when the rod descends a certain distance the collar will strike a bridge or obstruction, which will stop the farther descent of the rod, so that it is impossible to punch the diaphragm down into the fluid-cup.

The hole through the bridge is large enough to avoid friction, as the slightest amount of friction prevents accurate weighing.

The diaphragm is formed of a central plate, i, preferably made in two parts for the purpose of more easily and firmly attaching it to the diaphragm j. The rod f is attached to these center plates or pistons, as shown in Fig. 4. The size of these plates 2' determines the effective area of pressure which affects the rod f. The diaphragm j is made of flexible material, which should be made or rendered impervious to the liquid contained in the cylinder H, and it is attached to this cylinder as shown in Figs. 4 and 6, or by other suitable means, the area of pressure at the top of the cylinder being very considerably larger than the diameter of the tube leading to the scale n, so that any slight movement of the diaphragm shows a considerable variation on the liquidscale.

The diaphragm is preferably a fabric commonly known as London pocketing, underlined with a thin sheet of rubber; but leather, laminated rubber, or other suitable material may be used.

The cylinder H has an interior diameter of from two to six inches, four and a half being preferable. Abent tube, Z, is connected with the cylinder at one side, and may be provided with a stop cock, m, and also with an enlargement, as shown at Fig. 4, which enlargement will prevent air being drawn into the cylinder H in case of any excessive upward movement of the diaphragm in adjusting or by accident; but such enlargement is not absolutely essential to the proper operation of the device,and the pipe Z may therefore be of the same size for its entire length between the tube 0 and cylinder H.

The glass tube '0 is made of sufficient length to show the extreme variations of the liquid column in the tube, and it is attached to the pipe land to the overflow-bulb M by suitable couplings, which will prevent the escape of any liquid. The cylinder H,as shown in Fig. 4, is provided with a reservoir, R, from which the liquid used is permitted to flow into the cylinder in filling it, and afterward, as occasion may require, by simply turning the stopcock, which is turned back when the filling is completed. The filling of the cylinder H with liquid should be performed in such manner as to entirely exclude or permit the escape of air, which may be accomplished by tipping it, as the presence of air or other compressible gas between the diaphragm and the liquid will detract from its usefulness and accuracy.

The liquid contained in the cylinder should be non-freezing for exposed situations, and as mercury and the oils oxidize I do not regard them as suitable liquids to be used. Where the scale-beam is housed water may be used; but where it is not, wood alcohol is the best liquid known to me for filling the cylinder. When either water or wood alcohol is used it will improve the facility of reading the scale to color the liquid.

It will be understood that the rod f receives the same benefit from compounding the levers beneath the platform that the rod E does, so that the pressure upon the cylinder H is correspondingly light as comparedwith the weight on the platform.

In weighing atrain of cars the poise G is set to indicate a weight less than that of any car in the train; or, in a train where the cars vary greatly in weight, it may be set several times, but always showing less than the weight of the next car to be weighed. As a car rolls ontotheplatform,thesuddenly-appliedweights of the successive pairs of wheels and the sudden relief from the car just passing off gives the beam B a series of severe shocks or blows through the levers connecting it with the platform.

Any movement of the scale-beam is communicated to the rod f either through the point (1 orknife-edge (1 bearing upon the short arm of the beam B. Any movement, tremor, or vibration of the scale-beam is,'through the nature of the connection, conveyed to the diaphragm-plates i, and by them to the diaphragm j, where it is checked, as,the diaphragm being practically inelastic and in direct contact with the incompressible liquid in thecylinder,such sudden movement or vibration,which is in the nature of a shock or blow, is absorbed or connteracted by the inertia of the incompressible liquid in the cylinder, for the reason that the liquid can only escape through the small orifice leading to the tube Z, and the friction of the liquid on the walls of the tube. Any upward blow on the rod f is effectually checked, because the diaphragm, being directly connected to it,must rise with it,which movement cannot take place without an extraordinarily rapid flow of liquid from the tube Z back into the cylinder, or without lifting the diaphragm against the pressure of the atmosphere. The vibrations are all through a very small or limited space, so that the necessity of practically inelastic means of controlling them is necessary. While these dynamic effects are being resisted, the static load, over and above what is indicated by the poise O, is being brought into equilibrium with the pressure on the diaphragm, and shown by the height of the column in the tube 0 in connection with the scale at.

The reduction of the column in the tube 0 to a steady height shows the complete absorption of all vibrations, and the figures on the indicating-plate 11. represent the weight which is to be added to the weight shown by the poise 0, thus giving the total weight of the load on the platform. These fluctuations in' the tube come to a rest so speedily that the excess of weight above that indicated by the poise can be determined within a sufficiently 5 short space of time to accurately weigh mov- 10 rangement is deemed preferable, it is evident that they may be attached to the long arm near the hangerD without any material change in structure or operation.

WhatI claim as new, and'desire to secure by 1 Letters Patent, is.-

1. The combination,with a lever scale-beam and poise, of a liquid indicator arranged to operate with the fulcrum end of the beam,snbstantially'as and for the purposes specified.

2o 2. The combination of the cylinder H, diaphragm z j, adjustable rod f, and yoke c with a lever scale-beam, substantially as described.

3. The combination of the yielding diaphragm ij and rod f with the bridge H and limit collars or stops h, substantially as described.

4. The combination of the beam B, rod f, and cylinder H, having a yielding top or diaphragm, with the tubes Z 0 and overflow-bulb M, substantially as described. N

5. The combination of a. lever scale-beam having afluid indicator or scale connected with its short arm with the disk J, having a scrollslot, at, and pin b on the long arm of the beam, whereby undue pressure on the fluid-holder is prevent-ed, substantially as specified.

FRANK S. WASHBURN.

WVitnesses:

ALBERT H. ADAMS, HARRY T. J ONES.