US1982078A - Thermostatic control - Google Patents

Description

7 Nbv. 27, 1934. J. A. SPENCER THERMOSTATI C CONTROL Filed me 15, 1931' Patented Nov. 27, 1934 UNITED STATES PATENT OFFICE THERMOSTATIC CONTROL Application June 15, 1931, Serial No. 544,454 8 Claims. (01. 169-37) This invention relates to thermostatic controls and with regard to certain more specific features to a thermostatically operated fluid distributor head or valve.

Among the several objects of the invention may be noted the provision of a thermostatic control of general utility, but which is particularly employed as a temperature-controlled fluid distributor head or valve which is adapted positively to act to release a fluid flow substantially instantaneously, and which is not subject to great variation in operating characteristics, such as a critical temperatures, or to deterioration; the provision of a'valve or head of the class described which is not permanently impaired, so as to require replacement of parts, with each operation thereof; the provision of a valve or head of the class described which is adapted to distribute fluid over a relatively wide area; the provision of a valve or head which will not close or clog with fluid pressure variations after once it has been opened, except through intentional manipulation; and the provision of an article of the class described which is simple and economical in construction and reliable in operation. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly comprises the elements and combination of elements, features of construction, and arrangements of parts, which will be exemplified in the structure hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing in which is illustrated one of various possible embodiments of the invention,

Fig. 1 is a vertical section of a valve or head embodying the invention;

Fig. 2 is a top plan view of the valve of Fig. 1;

Fig. 3 is a vertical section similar to Fig. 1, showing an advanced operating position of the valve of Fig. 1; and,

Fig. 4 is a vertical section similar to Figs. 1 and 3 showing a more advanced operating position of the valve of Fig. 1.

Similar reference characters indicate corresponding parts throughout the several views of the drawing.

Attempts to operate fluid distributor valves or heads such as sprinkler heads and the like for flre protection by means of a thermostatic element have heretofore been unsuccessful in that their operation has not been sufliciently quick, positive or reliable. One present type of sprinkler head, emplo a fusible link or plug to obtain a medium sensitive to a critical temperature, has the disadvantage that such a link cannot-be made to fuse at a temperature as low as is desirable and still retain reasonable mechanical strength. Further, such links often change their fusing points with age. Furthermore, each time the valve is operated, a replacement with an entirely new fusible element is necessitated.

The present invention overcomes the difficulties formerly encountered with thermostatic elements as mediums for obtaining action at a critical temperature and provides a thermostatically operated fluid distributor valve which is positive acting, reliable, and which does not change its critical temperature with age. Moreover, by using the present invention a sprinkler may be provided in which a wide range of critical temperatures may be obtained by using different thermostatic elements, and lower critical temperature may be reached than has heretofore beenpossible with the fuse link. Also, no element is required to be replaced with a corresponding new elementafter each operation of the'valve, as is the case with fusible links or plugs.

Referring now more particularly to Fig. 1 there is shown at numeral 1 a thermostatically operated valve adapted to be used as a sprinkler head, in cold, closed position, mounted on a pipe 3 which is adapted to convey fluid under pressure, such as'water. The sprinkler 1 comprises a base portion 5 which is threaded on the pipe 3 and from which leaf springs 7 extend upwardly. The tops of the springs 7 are bent over as shown in Figs. 1 and 2 to engage a washer 9. A valve stem 11 passes through the central opening of the washer 9, and a valve head 13 on the stem 11 is adapted to seat in a valve seat 15 formed in the pipe 3, to positively cut off communication between the, inside and outside of the pipe 3.

The valve head 13 is positively held in the seat 15, against the pressure of the fluid in the pipe 3, indirectly by means of the springs 7. The springs 7 accomplish this holding by reacting downwardly on the washer 9, which in turn presses against portions 17 of a thermostatic disc 19, portions 21 of which press axially against a shoulder 23 formed on the stem 11. The element 19 thus acts as a stop and the springs 7 are adapted to maintain the valve head 13 in its seat 15 by a substantially perpendicular pressure. The thermostatic disc 19 is free at its outer edges 25. The pressure on the edges 17 and- 21 is a compression perpendicular to the plane of the disc applied at the center thereof and thus is so placed that it does not affect the snap-acting nally formed concavity in one direction.

properties of the disc 19. Other means may be used whereby the element 19 is adapted to stop the valve stem. It is seen from the drawing that the stem 11 passes through an opening 27 in the disc 19.

The thermostatic 'disc 19 is preferably of the general type illustrated in my copending application filed June 26, 1930', serial No.. 463,961 no'w Patent No. 1,895,590, granted January 31, 1933. Briefly, the thermostat comprises a disc of thermostatic metal such as-is usually termed bimetallic or composite metallic, and is preferably, radially corrugated as shown at numeral 29 and as shown in Fig. 1 in the cold position, the radially corrugated portion 29 has an origi- A thermostat of the type illustrated has the property, upon its being brought to a certain temperature, of reversing its direction of concavity. In other words, if the disc be originally considered concave, it becomes convex, or vice versa. The explanation of this phenomenon, is disclosed in my aforementioned Patent No. 1,895,590.

The corrugated disc 19 has the peculiar property that when it snaps, the opening 27 changes in shape and by properly dimensioning said opening, as shown in Figs. 1 and 4, it is conical in a cold position of the disc, and substantially cylindrical in the hot position, as shown in Fig. 3. The smallest diameter, occurring in the cold position, is less than the uniform diameter of the cylinder formed by the opening 27 when the disc is in the hot position. When the disc 19 snaps to its hot position, the change in size and shape of the opening 27 is sufiicient to allow the stem 11 to freely pass through the opening 27. It is noted that the portion.31, which is depressed below the rest of the stem 11, forms the shoulder 23, and at when normally in its cold position as shown in Fig. 1, the portions 21 of the disc 19 grip the depressed portion 31.

The operation of the invention as installed in a water, fire protection system is as follows.

The sprinkler head 1 is installed with the pipe 3, which for example, carries therein a relatively high water pressure. The head is assembled as shown in Fig. 1 and seals the pipe 3.

If now the temperature of the disc 19 is raised above its critical temperature it will snap to its hot position as shown in Fig. 3. This snapping, however, as hereinbefore described, changes the shape of the hole 2'7 and the portions 21 are snapped out of holding contact with the shoulder 23 on the stem 11. -It is to be noted here that a top portion 33 on the stem 11 has a diameter slightly larger than the main portion of the stem and thus larger than the outer diameter of the shoulder 23 but not quite as large as the uniform diameter of the opening 2'7. In this way as the disc 19 snaps to its hot position the portion 33 centers the stem 11 in the center of the opening 27, positively preventing any of the portions or edges 21 from catching on the shoulder 23.

With the stem thus freed the water pressure acting on the valve head 13 forces it from the seat 15 and thereby forces the stem 11 up through the opening 27, the stem as hereinbefore described being adapted to freely pass through the now cylindrical opening 27. The force of the water escaping raises the valve stem to the top of its motion and holds it there, the valve head and disc 19 forming a distributor for the water.

The cold water; however, escaping from the pipe 3,cools the disc 19 below its critical tempera.-

nesaovs ture and it snaps again to its cold position, as shown in Fig. 4. At this stage, it again grips stem 11 with the edges 21 and inasmuch as the springs 7 limit the movement of the element 19, the valve head 13 is positively held above the seat 15. In

"this position the cold disc 19 and valve head 13 form an efiective directing surface for the water.

'Itis noted that when assembled to seal the pipe 3, as shown in Fig. 1, the force exerted on the disc 19 is substantially perpendicular to the plane of the disc and that in snapping to its hot position the pressure at the portions 21 and 17 will not interfere with the operation of the disc and hence varying water pressures in the pipe 3 will have substantially no effect on the critical temperature ofv the disc.

An advantage of the invention is that a snapacting thermostat has been adapted to a sprinkler head and that the control and action obtained is positive and reliable. An advantage of the thermostatic element thus used in sprinkler heads is that such discsmay be provided which will eiiectively operate at a much lower temperature than the old type of fuse link could be used for. Further inasmuch as the critical temperature of the element 19 does not change with age sprinkler heads installed employing my invention will not require inspection. I i

The assembly may be returned from the Fig. 4 to the'Fig. 1 position, when, for example, it is desired to stop the ilow of water, simply by manually forcing-the thermostatic disc, while is required to be replaced, and the valve is again the springs 7 and seat 15 are formed in the factory and may thus be sold as a unit to be installed in pipes of the system. 1

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructions without departing from the scope oi the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A fluid distributing valve constructed and arranged to operate at a predetermined temperature to deliver fluid, said valve including a thermostatic element having a hole therethrough, and a stem on said valve passing through said hole, the dimensional characteristics of said hole changing with the temperature-determined alternative positions of said thermostatic ele ment, alternately to restrain and permit free movement of said valve stem.

2. A fluid distributing valve constructed and arranged to operate at a predetermined temperae ture to deliver fluid, said valve being normally maintained in a fluid retaining condition by a snap acting thermostatic element, said element having a hole therethrough, and a stem on said valve passing through said hole, the dimensional characteristics of said hole changing with the to freely move through said hole when said element is in its alternative position.

3. A valve for distributing fluid under pressure having a valve stem, comprising a thermostatic disc having a hole therein through which said stem is passed, the shape of said hole being such that a portion of said element engages a shoulder on said stem when said element is in one of its alternative positions and said valve stem is in its closing position, and resilient means adapted to press against said element to hold said valve stem in its closing position against said fluid under pressure, and the shape of said hole being changed when said element snaps to its alternative position, the then resulting shape being adapted to allow free passage of said stem through said hole, whereby said valve is forced open by said fluid under pressure.

4. A valve for distributing fluid under pressure having a valve stem, comprising a thermostatic disc'having a hole therein, through which said stem is passed, the shape of said hole being such that a portion of said element engages a shoulder on said stem when said element is in one of its alternative positions and said valve stem is in its closing position, and resilient means adapted to press against said element to h ld said valve stem in its closing position aga%st said fluid under pressure, and the shape of s id hole being changed when said element snaps to its alternative position, the then-resulting shape being adapted to allow free passage of said stem through said hole, whereby said valve is forced open by said fluid under pressure, and means formed on said stem adapted to center said stem in said opening when said element snaps to its last-named position.

5. An assembly for delivering fluid under predetermined temperature conditions, including a snap acting thermostatic element having a hole therein, and a valve having a stem, said stem passing through said hole, said element having alternative positions determined by the ambient temperature, said thermostatic element being constructed such that, in one of the positions of said element, it engages the stem to prevent open ing of said valve, and, in the alternative position of said element, it disengages the stem to permit free opening of said valve.

6. A thermostatic control comprising a snapacting, radially corrugated composite metallic disc, said disc having a hole in the center thereof, said hole changing shape as the disc snaps from position to position, and a controlled element fitting in said hole, said controlled element being so shaped that it is locked against movement in at least one direction relative to said disc by said disc in one position of said disc but is permitted freely to move relative to said disc when said disc is in another position.

'7. A thermostatic control comprising a radially corrugated composite metallic disc, said disc having two positions of stability and moving therebetween, in response to temperature changes, with a snap action, said disc having a'hole at the center thereof, said hole having a lesser diameter in one position of stability of the disc than in the other position of stability, and a controlled element fitting in said hole, said controlled element being of such diameter that it is locked by said disc against movement in at least one direction relative thereto when said hole is in its said condition of lesser diameter, but is permitted freely to move relative to said disc when said hole is in its condition of greater diameter.

8. A thermostatic control comprising a radially corrugated composite metallic disc, said disc having two positions of stability and moving therebetween, in response to temperature changes, with a snap action, said .disc having a hole at the center thereof, said hole being conical when said disc is in one of its said positions of stability and substantially cylindrical when said disc is in its other position of stability, the diameter .of said hole when cylindrical being greater than the minimum diameter of said hole when conical, and a controlled element fitting in said hole, said controlled element being of such diameter that it is locked by said disc against motion in at least-one direction relative thereto when said hole is in its said conical position, but is permitted freely to move relative to said disc when said hole is in its said cylindrical position.

JOHN A. SPENCER.

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