US41868A - Improved spring-tension regulator - Google Patents

Description

PATENTED MAR. 8, 1864.

T. SILVER. SPRING TENSION REGULATOR.

. l/IW/ I I WLTIMSSM." 7f

"MM Ohm- UNITED STATES THOMAS. slnvnn or NEW YORK, n. v.

, lMPROVED 'SPRING-T PATENT OFFICE.

ENSION neon LATOR.

Specification forming part ofrLettcis Patent No. 11,868. datcdh'larchfi, 1864.

To all whom it maycon'cern:

L Be it known that I, THOMAS SiLvnR, of the city of- Nc'w York, in the county and State of New Yorlghaveinvented a certain new and useful Spring-Tension Regulator; and I do hereby declare that the following is a full, clear, and exact description lit. the same,-reference being had to the accompanying drawings, making a part of this'speeilication, and to the letters of reference marked thereon.

When it is desirable to compress or extend a spring, the intensity of the forcef zpeplied must be constantly increased in proportion tov the increased resistance of the spring, as the degree of force which will extend or compress. it one inch from its normal position must be greatly increased to move it an atd'Ltional inch. In the case, for example,'0f the ordinary application of a spring safety-valve to a boiler, the valve may begin to open by the pressure of steam at. the point desired; but it will require aconsrderable additional pressure to open the valve still farther to permit the escape of an amount of steamsutfieient to relieve the boiler. It is this constant increase of tension in a spring that has rendered the application of a weighted lever preferable in many cases, as, for instance, on a sea-going steamer where the motion of the vessel conflicts with the inertia of the weight and ma terially al'l'ecls its utility. \\"hen a vessel has a stormy voyage, the relief of the load on the safety-valve, owing to the'pitching and rolling of the vessel affecting the stability of the weight, may occasion the-losscf a large percentage of steam, and it will be understood that this isihe more likely to occur because the effect of the weight on the valve is brought into a condition approximzu ingan eipiilihrium by the slight difference between. the working- .pressure and the blowing-oft point.

The object or my invention is to equalize or to vary in effectthe increasing tension 0t any known form or variety of spring, whether in a state of extension or contraction, as may he required for the diiferent modifications ol' r e-- sistance and power involvedin mechanical pa 1'- poscs. Xihen it is desired, for example, to

use a spring as asnbstitutc for a-weight in the noading, of a safety-valvelever of a steam- )oiler under circumstances of locomotion which miglitislisturb thc action of the forcddit is torbr m a means of adjusting a spring to such an equilibrium of force that it shall resist permanently a determined pressure upon the valve; but when the said pressure may be exceeded the valve-lever maybe allowed to rise toopenthe valve in the same manner as if it had been confined by a weight,and the whole throw or motionof thelever will be madewithout the increase of resistance that would be the case with aspring applied-in the ordinary manner. To attain this-=ob iect my invention consists in combining, the: spring transmitted in such a manner that it is first applied to the long radius, and continued by the turning. of the eccentric, so that the leverage of the eccentric'is diminished asthe'int-ensity of the spring is increased, the greater force of the spring having ashortcrqlever to operate upon; and in a simi' ar manner by passing the chef n or othcr fletible connection of the spring and valve (or other machinery to which the tercnce of the eccentric, the power of the spring is transmitted from the eccentriUW'ith a constant increase of leverage in proportion to theincrcasein tension of the spring,so that the increased force of the spring operating upon its shorter lever has also its resistance tionfor the variations of the force of the spring by the leverages through which it is app] ied is, that when th degree of eccentricity is properly proportioned the entire range of the expansion or cont raction of a spring willbe rendiered uni form and liilllill,tllltl by changing the iarh'ount ot' eccentricity the equilibrium will be destroyed, on the one ha'nd,by shiftingthe axisnl' tilt-eccentric so that it becomes merely a pl iiley the action of the spring is unchanged,- and on the other by shifting the axis beyond 1 in. pointol'equilibrium the action ofthe spring will be diminished in intensity instead of ta.

creased. I

To enable others skilled in the art to which it app gptnins to make and use my invention, 1.

""wil'l' proceed to describe its construction and I operation with reference to the drawings. 1 l igurcl is a front view of my said invent-i n I ,g'raviflyoff'a iveig-lihthe object of nfiyinvent i on with 'a'portiou of the l'ranieunnovcd, so as to with an eccentriqthrough which its power is spring is applied) around one-half the cireumplaced upon a. longer lever, occasioningacon-- version of the increased force and lessened.- range of the spring to a diminished force and extended range. T he result of this compensa exhibit the spring which is in its uormal'posi tion and Fig. 2is a sideview of the same.

Fig. 3% a front view with the spring extended and aportion of the frame also removed. Theeecentricc is made with a slot,through which passes the axis 6,. which is maintained in -any required position of eccentricity by means 'of the screw 0. The chain (1 passes over the ethentrie and isatiaehed to it at the screw 0 or elsewhere, so that it moves with the cocentric, and itis connected atone side to the spring 6, anglat' the other to a rod, f, by the loop, in the end of whiehlt may be connected regulated as may be required. The axis b is siipported by the vibrating frame w,on which it rolls,instead of beingeonfined in journals in the frames, bywhich means the friction is greatly diminished.

\l'hen it is d sirable to have 1.1 increased leverage motion without enlarging the ec same purpose, or eccentrics of different sizes may be used, so that an elliptic or indie-nubher or other spring of small movement may afford a large, range of application. \Vith a ehronometer 0r true spiral spring one end of the spring should be attached to the shaft,and the opposite end to a ratehet-wheel which can be turned and secured in adjusting the tension of the spring.

Having thus described the manner in which I prefer tomake and apply my said invention, I wish it tobe understood that I do not confine inyselt'to that precise manner of construe tion or applieationoi't-heprinciple of varying the leverages to said different degrees of tension; hut

\Vlrat Ido claim as my invention is' The combination of a'spring with an cecentrie, substantially as described for the pm pose specified.

rn'mL-ts sinvna.

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