US1786852A - Thermostat - Google Patents

Description

Patented Dec. 30, 1936 UNITED STATES JOHN J. KENNEY, OF PITTSBURGH, PENNSYLVANIA THERMOSTAT Application led December 12, 1928.. Serial No. 325,421.

The present invention relates broadly to the art of temperature responsive devices, and more particularly to a thermostatically operated valve. The utility of the present invention however is not limited to the combination of a thermostat and valve, the invention being adaptable to the thermostatic actuation of a wide variety of diiferen't .controlling means such as valves, switches and the like. Such controlling means are hereinafter referred to in the specification and claims in generic terms.

It is customary present invention relates Vto provide thermostatically operated structures, such as valves, with the member to be actuated either in alinement or` oifset from the axis of the heat responsive mechanism by which the actuation is eifected. It is also customary to pro- '20' vide adjusting means whereby the temperature range through which the device is op-l erative may be varied at will.

The present invention has for one of its objects the provision of an improved adjustin means which is not onl capable of easy adjustment, but which enab es an adjustment of almost micrometric characteristics to vbe obtained.

In the accompanying drawings I have shown for purpose of illustration only, certain preferred embodiments of the present invention.

In the drawings, Fi re 1 is a lon "tudinal sectional view-throng oneform o thermo-v static device constructed in accordance with the present invention, and y Figure 2 is a partial sectional view, similar to Figure 1, but illustrating a slightly modified embodiment of the present invention. 1

In carrying out the present invention there macy be provided a thermostatic mechanism in udng a supporting body 2, herein illustrated as comprising a valve casing, in cooperative relation to a heat responsive actuatin means 3.

the specific embodiment of the invention illustrated in Figure 1, the heat responsive means comprises a relatively expansible 5 and contractile casing 4 with a relatively in the art to which the` non-expansible and non-contractile rod 5 carried thereby. The casing 4 is conveniently closed at one end to provide an abutment for onel end of the rod 5, and is enlarged at Aits opposite end to provide a threaded portion 6 adapted to be threaded into position in a container or other body. Adj acent the threaded portion is formed a chamber 7 within which is positioned an extensible unit 8 in the form of a iiez'rible casing ada ted to contain a bod of liquid. The liquid utilized will prefera 1y be chosen with respect to its ability to retain a substantially constant volume under temperature changes.

The unit 8 may conveniently comprise a substantially cylindrical corrugated or bellows shaped casing, the ends of which are secured respectively to a disk 9 and aicap 10 in such 'manner as to proyide duid tight joints therewith. The disk 9 may abut directly against the rod 5 while the'cap 10 may in engagement with the stem 11 of a valve 12 within the supporting body 2.

Threaded through one of the side walls of the cap l0 is a screw 13 provided on its-outer end with a thumb screw or adjusting wheel 14 by means of which it may be turned to cause it to project a greater or lesser extent into the interior of the unit 8. When the screw is turned in such direction as to cause it to projecth into the unit, it will ,be apparent that the space for the liquid is decreased, thereby causing the unit to expand and decreasing the lost motion between the rod 5' and the valve stem 11. As the screw is turned in the opposite direction, however, a greater space is available for the liquid, thereb permitting the unit 8 to contract and provi e a greater 'lost motion between the parts referred to. Under the condition first referred to, a relatively smaller change in the temperature of the'thermostat will be effective for unseating the valve'12, while under the condition last mentioned it `will be necessary to subject the -thermostat to a higher temperature in order to effect such an operation. It becomes apparent therefore vthat by means of the screw 13 it is possiblel to accurately control the exact temperature at which the device becomes elfectiveifor untherefrom, which arms at their extremity.

16 secured to the rod 5 and having a tight' seating the valve or ede'cting actuation of some other movable member which itis desired to control. By providing the thumb screw or hand wheel llqwith suitable graduations or calibrations adapted to cooperate with an index, pointer or the like, (not shown), it is possible toetlect an extremely cllse adjustment in one direction or thel ot er. .Y

In Figure 2 there is illustrated a slightly modified Vembodiment of the invention in which parts corresponding to the parts already described are designated by the same reference characters having a prime aiiixed thereto. j

In this form of the invention the supporting body 2 has spaced arms l5 projecting carry a cylinder 7. Extending into the cylinder 7 at one end isthe stem 11 of the member to be actuated, While cooperating with the cylinder at its opposite end is a piston fit Within the cylinder. Extending through thel cylinder wall is an adjusting screw 13v operative in the manner referred to in connection with the screw 13 for varying the available Vroom for the liquid. With this 1 respective of variations in the temperature.

to which it is subjected. An adjusting screw, similar to those already described, may be utilized for displacing such shot and producing results comparable to those which are prqduced where a true liquid'is utilized.

It will also be apparent to those skilled in lthe art that I may suit-ably heat insulate the particular portion of the device in which the fluid or medium having flow characteristics is contained, to thereby shield it to as great f an extent as possible from any heating in.

fiuences. v

Certain advantages of the present inven tion arise from the provision of a'heatresponsive mechanism in which a member vto be moved isactuated Iby a heat responsive mechanism through the medium of means having flow-characteristics.

Otherl advantages of the invention arise from the provision of the structure of the character 'referred to'in which the medium y having flow characteristics may be easily and "accurately subjected to "anvadjustiig' influence in manner that .the temperature if/eases conditions under which the movable member is actuated may be accurately controlled.

While I have herein illustrated and described certain preferred embodiments of the present invention it will be understood that changes in the construction and operation of the parts may be made without departing either from the spirit of my invention or the scope thereof as defined in my broader claims.

I claim:

l. A thermostat, comprising a supporting body, a member movably carried thereby, a solid heat responsive device for actuating said member, and means of substantially constant over-all dimensions having flow characteris'tics for transmitting operatin pressure from said solid device to said mem er.

2. A thermostat, comprising a supporting 4 body, a member movably carried thereby, a solid heat responsive device for actuating said member, and a medium having flow characteristics but confined against ow and interposed between said solid device and said member for transmitting pressure from the device to said member. l

3. A thermostat, comprising a supporting body, a member movably carried thereby, a heat responsive device for actuating said member, means f substantially constant volume having flow characteristics for transmittin operating pressure from said device. to sai` member, and means for varymg thev eii'ectivev volume of said tirst mentioned means.

.4. A thermostat, com rising a supporting body, a member movab y carried thereby, a heat responsive device for actuatin said member, and a fluid vcontaining cham er of substantially constant over-all length intermediate said device and said member for transmitting pressure from said device to said member, the fluid in said chamberu being such `as to retain a substantially constant volume under temperature changes.

5. A thermostat, comprising a supporting body, a member movabl57 carried thereby, a heat responsive device for actuatin said member, and a fluid containin cham erintermediate said device and sai member for transmitting pressure from said device to said member, there being means for changing the eiective volume of said chamber, the fluid in said chamber being such as to retain a substantially constant volume under temperature changes. f

6. In a thermostat, a supporting body, a member movably carried/therebyya heat res onsive device secured in cooperative relation to said member but spaced therefrom,

an actuating medium having a substantially negligible coeicient of expansion and hav-Y ing flow characteristics located intermediate sa1d device and said member, and means con.- fining said medium against ow.

7. In a thermostat, a su porting body, a member movably carried tlgereby, a heat responsive device secured in cooperative relation to said member but spaced therefrom,

and an actuating medium havin flow characteristics intermediate said devlce and said member, there being means for var-yin the effective volume of said medium at wilg, the Huid in said chamber being such as to retain m a substantially constant volume under temperature changes.

In testimony whereof I have hereunto set my hand.

JOHN J. KENNEY.

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