US1500566A - Thermostat - Google Patents

Description

Patented July 8, 11924.

, I 1,500,566 PATENT l OFFICE...

LEE P. HYNES, OF ALBANY, NEW YORK, ASSIGNOR TO CONSOLIDATED CAR-HEATING COMPANY, OF ALBANY, NEW YORK, A CORPORATION OF WEST VIRGINIA.

Y THERMOSTAT.

Application led April 18, 1922. Serial No. 555,173.

To all 'whom it may concern:

Be. it known that I, LEE P. HYNES, a

citizen of the United States, residin at f Albany, in the county of Albany and tate of New York, have invented certain new and useful Improvements in Thermostats, the following being al full, clear, and exact i disclosure of the one vform of my invention which I at present deem preferable.

lFor a detail description of the' present form of my invention, reference may be had to the followin speciication and to the accompanying drawings forming a part thereof, wherein- Fig. 1 is a longitudinal section;

Fig. 2 a front view with cover removed;

' Fig. 3 is a rear view, with the base removed, and

Fig. 4 is a transverse section on lines 20 4 4 of Fig. 1. My invention relates to a thermostat of the mercury type designed to open and Jclose an electric circuit at predetermined temperatures. Heretofore it has been roposed to connect the thermometer bulb 1n a thermostat of this type with a cover-plate of special heat-responsive metal, through which the temperature-changes in the outer atmosphere are communicated to the bulb. In this device, the large surface of heatresponsive metal, together with the-other metal parts associated therewith tend to make the action of the device sluggish, its response to temperature changes being so gradual as to impair the electric contacts, particularly on the opening of the circuit.

Moreover, such instruments areA ordinarily mounted on the wall of a car or apartment wherein heat is inevitably stored, and soon come to partake of such stored heat and acquire a temperature that is not quickly changed by changes in the atmospheric temperature.

My invention resides in the use of a comparatively small heat-responsive 'element which is effectively heat-insulated from the cover or casing but applied directly to the thermometer-bulb. This element is exposed to the atmosphere on the outside of the cover or casing but is heatinsulated therefrom and passes ythrough narrow slots into the inside of the casing where it is wrapped around the bulb of the thermometer. By this means I secure a movement of the mercury column that is heat-responsive quick and positive such as is needed for opening an electric circuit at the contacts D. I am also enabled, by this expedient, to use a cover or casing of heavy steel plate that will adequately protect the delicate glass thermometer inside of it.

In the drawing, A represents a base of moulded material and B a metal casing or cover of steel suitably secured to the base.

On the inside of cover B is a mercury `thermometer of glass having metal contacts D, D, set therein and exposed to the mercury within the glass tube, but without breaking the vacuum therein. From each of the contacts D, a wire leads to one of the tubular terminals E, E set in the base E and provided with binding screws in each end. Thermometer'C is mounted at one end in a cushioning bushing and at its lower, or bulb-end, is surrounded by a strip G of thin copper or other composition that is sensitive to changes of temperature. The bulb is lightly clamped within this strip G by a screw g, as is shown in Fig. 4 and the strip itself extends thence through a narrow slot in the casing B, and, after passing across the outer face of the casing passes back into it through a similar slot on the opposite side and is there bent over to secure it in place. A layer of heat-insulating material F separates and insulates the sensitive strip G from the metallic casing or cover B, on all sides, whereby its response to heatvariations are independent thereof. That serves toeliminate the slow and uncertain effects of heat-variations in the steel cover B from the mercury of the thermometer. The mercury responds directly to the heat effects in sensitive strip 21 Without disturbance by the effects in the casing- B.

This will be realized by considering that the exposed portion of strip G is comparatively small and has but a slight capacity for heat storage although of good heatconducting capacity. Therefore it canreceive or -lose heatto its 'full capacity long before there can be any material flow of heat in either direction through the insulating layer F from or to the mass of heat in the casing itself and the wall on which it is mounted.

What I claim as new and desire to secure by Letters Patent is: y

1. A thermostatie control-device comprising a base, a cover cooperating with said base to provide an enclosure, a thermostat and an element of temperature-sensitive material applied to said thermostat within said inclosure, a portion of said temperaturesensitive material being exposed v,to the atmosphere outside of the inclosure and actf port.

ing on the thermostat independently of the enclosure and an electric contact controlled the thermostat.

2. A `thermostatic, control-device comprising a base, a cover cooperating with said base to provide an enclosure, a thermostat, an electric contact controlled by the thermostat and an element of temperature-sensitive material applied to said thermostat within said enclosure, said material having a portion thereof passed through sai-d cover for external exposure to the atmosphere whereby said element will act on the thermostat independently of the enclosure.

' 3. A thermostatic control-device compris- -ing means providing an enclosure, a thermotat within said enclosure, an electric contact controlled thereby a temperature-sensitive element applied to the thermostatic device within the enclosure, means for supporting said element with a portion thereof exposed to the atmosphere outside of said enclosure and. means for insulating said element from temperature changes of its supcontrolled by said thermometer and a temupon said enclosure, an electric contact controlled by said thermometer, a temperaturesensitive element constructed independently of the enclosure-forming means, vsaid element engaging the bulb end of the thermometer and having a portion exposed to the outside atmosphere and means for insulating said temperature-sensitive element from temperature changes of the enclosureforming means.

7. A thermostatic control-device comprising a base, a cover cooperating with said base to provide an enclosure, a thermometer within said enclosure, an electric contact controlled by saidvthermometer and a temperature sensitive element secured to and heat insulated from said cover, said element engaging the bulb end of the thermometer and having a portion exposed to thev outside atmosphere.

8. A thermostatic control device comprising a base, form an enclosure, a thermometer within said enclosure, an electric contact controlled by said thermometer, a lbulb-engaging clip formed of temperature sensitive material having a portion thereot` extended through said cover, whereby said portion is exposed to the -externalatmosphere and the clip is supported and means for insulating said clip from temperature changes of the cover.

Signed at Albany, county of Albany and State of New York, this 13th day of April,

LEE P. HYNES.

a cover cooperating therewith to

Images