Патент USA US2121259код для вставки
June 21, 1938. ' F, A, PARSONS 2,121,259 THERMOSTATIC ELEMENTS Original Filed June 26, 1950 LINVENTOR M 6?. PM “4,2221%, ATTORNEYS 2,121,259 _ Patented June ‘21, 1938 PATENT OFFICE UNITED STATES 2,121,259 . THERMOSTATIC ELEMENTS Fred A. Parsons, Milwaukee, Wis. _ Original application June 28, 1930, Serial No. 483,976. Divided and this application May 24, 1934, Serial No. 727,256 _ (Cl. 297-16) This invention relates to improvements in 'diiierent metals, preferably resilient and neces thermostatic elements. The present application sarily having dlil'erent coeii‘icients of thermal ex is a division of my application No. 463,976 ?led pansion. The minor helix or helicoidal member 11 Claims June 26, 1930. The object of the invention is to provide a 5 helical form of thermostatic element which will give an axial response and may be made either to expand or to contract its length in response to an increase in temperature. More particularly stated, it is the purpose of 10 the invention to provide a bimetallic thermo static element which will give a relatively large response to given temperature change while oc cupying relatively small space, such response being attributable to the winding of the thermo 15 static element into helical form and then wind ing the helix into a larger helical form, the di< rection of response being determinable accord ing to which one of the metallic components of go the bimetallic strip is outermost in the original helix. In the drawing: Figure 1 is a side elevation of a thermostatic mentioned is so wound that one metal lies out side the coil and the other inside the coil, the 6 different metals being indicated at 35-36 in Figs. 2 and 3. The minor helix or helicoidal member is then itself axially coiled helically to comprise a major helix wound in the form of a helical spring or peripherally continuous hollow member, as indi cated at 32 in Fig. 1. The bimetallic spring so made will expand or contract in the direction of the axis of the major helix when the tempera-_ 7 ture of the structure is changed. It may be 1 stated that the described result in the major - helix is due to the fact that the winding of the minor helix is such as to produce a torsional or twisting effect along the axis of the minor helix when the temperature changes. ' In accordance as the one or the other metal is 25 with fragmentary portions shown in axial sec tion of a suitable mounting for the element. Figure 2 is an enlarged view of the element in end elevation. Figure 3 is an enlarged detail view in side ele positioned outside or inside of the minor helix, the major helix will expand or contract along its axis when heated. It may be assumed that reference character 35 indicates the metal having the lesser coeilicient of thermal expansion, while reference character 36 indicates the metal hav ing the greater coe?icient of thermal expansion. It will be noted that the positions of these metals 30 vation of a single coil element. ' are reversed as between Figs. 2 and 3. I element embodying this invention in association Like parts are identi?ed by the same reference characters throughout the several views. The casing fragmentarily shown at l0 carries pins 26 and 21 upon which the spring seat mem ber 25 is guided for adjustment under the con 35 trol of the threaded portion 29 of an adjusting shaft M. The thermostatically adjusted member 20 is guided for axial movement with reference to the seat member 25 by means of lugs 2l—22 engaged 40 in complementary notches 23-44 of the member 25. Members 25 and 20 have anchorage pegs 33 and 34 with which the thermostatic element 32 is engaged .at its’ ends. 45 ' mounting may be employed, the mounting illus trated having been reproduced from the drawing of the above entitled parent application for pur poses of exempli?cation only. 50 ‘ It will be understood that any other suitable ' The de- \ vice shown in Fig. 2 will tend to expand axially along its axis when heated, while the device shown in Fig’. 3 will contract axially valong the axis of the major helix when heated. Inasmuch as it is very desirable in some me chamcal installations to have a thermostat which will contract at a rapid rate when heated and will expand correspondingly when cooled, it will be obvious that the disclosed construction has advantages never heretofore realized. Obviously its overall coe?lcient of contraction when wound as shown in Fig. 3 is as great as its overall co e?icient of expansion when wound as shown in Fig. 2. In either direction the degree of move ment produced in- response to a given tempera. 45 ture change is very great in proportion to the amount of space occupied by the element. I claim: 1. A thermostatic control member comprising The thermostatic element 32 to which this in a bimetallic strip twisted to form a helicoidal vention particularly pertains, is conveniently member which is coiled in a generally'helical made by first winding a minor helix, in this case ' form. of relatively small diameter, out of a narrow strip of any well known bimetallic metal, com 55 prising two integrally jolnedstrips or sheets of - 2. ‘A thermostatic control member comprising a bimetallic strip twisted to form a relatively long helicoidal member of relatively small di 50' 2 2,121,259 ameter, said helicoidal member being axially coiled to form a peripherally continuous hollow member, the length of which changes with temj perature. ~ 3. A thermostatic element comprising a hol low axially expansible member comprising con volutions of an elongated thermally torsional member, said thermally torsional member com prising a hollow body constituted of a continu 10 ous bimetallic strip. 4. As a new article of manufacture, a thermo static element comprising a bimetallic strip wound to constitute an elongated and substan tially helicoidal member in which the metal of 15 said strip having the greater coe?lcie'nt of ex pansion is exposed outwardly, said member be ing coiled bodily in generally helical form to constitute said element. 5. As a new article of manufacture, a thermo static element comprising a bimetallic strip wound to constitute an elongated and substan tially helicoidal member in which the metal 01' said strip having the lesser coe?lcient of ex_ pansion is exposed outwardly, said member being coiled bodily in generally helical form to con stitute said element. 6. A thermostatic element comprising strips of metal of diil'erent coe?lcients of thermal expan sion rigidly connected along their length and ex tending progressively about a first axis which in turn is extended progressively about a second axis. 7. A thermostatic element comprising strips of metal of different coe?lcients of thermal expan~ 35 sion rigidly connected along their length and ex tending progressively about a first axis which in turn is extended progressively about a second axis, said strips together comprising a bi-metallic thermostatic spring having an axial thermo static expansion and contraction together with such resilience as is inherent in the metal oi said strips. . 8. A thermostatic element comprising strips 01' metal of different coe?icientsof thermal expan sion rigidly connected along their length and ex tending progressively about a first axis which in turn is extended progressively about a second axis, said strips together comprising a bi-metallic thermostatic spring having an axial thermostatic 10 expansion and contraction together with such re silience as is inherent in the metal of said strips, one of said strips being outside of the other throughout the extent of the spring. 9. An element of the character described, com prising a member in the form of a helix with an open center and subject to torsion when exposed to a changed environmental condition, said mem her being bodily formed into convolutions to com prise said element, whereby the twisting of said member occasions a change in the overall length of said element from one end of said convolutlons to the other. . 10. As a new article of manufacture, a thermo static element contractible along its axis when 25 heated and comprising a bimetallic helix elon gated in the direction of its axis and composed of a coiled strip of bimetal, the portion of said strip with greater coe?lcient of expansion being ‘so disposed that said helix will contract when heated. . 11. As a new article of manufacture, a bi metallic helix of axially elongated form compris ing a succession of axially progressing coils, at least one of which has at least one loop about an axis transverse with respect to the axis of said coils. FRED A. PARSONS .