US895702A - Steam-trap. - Google Patents

Description

I PATENTED AUG. 11, 1908. R. L. WALES. STEAM TRAP. APPLICATION FILED AUG. 2, 1907.

Matilda? ROYAL -L. WALES, OF KNOXVILLE, TENNESSEE.

STEAM-TRAP.

Specification of Letters Patent.

Patented Aug. 11, 1908.

Application filed August 2, 1907. Serial No. 386,801.

sensitive and eflicient trap allowing the passage of cold water, hot water, and air without allowing the passage of steam.

In the accompanying drawings, Figure 1 is an upright section along the axis of a trap embodying my improvement; Fig. 2 is a plan of the same apparatus, a portion being broken away.

Referring to said drawings, A is the casing of the trap. This is, in the main, cylindrical in form, and has a fitting, 1, at its lower end for the attachment of a waste pipe, and has a screw-threaded opening at the top to receive a cap, 2. Just below the cap is a branch connection, B, to which a pipe, C, may be joined in any suitable manner. Near the lower portion of the casing is a horizontal partition, 3, secured by screw-threading to the interior of the casing. For convenience in description, the space within said casing above said partition is herein termed the condensation chamber. At the center of said partition is a port or outlet, 3, around which is formed a valve seat, 4, which seat is adapted to receive a half-spherical valve, 5. Said valve is herein termed the main valve. Below said valve is a cross-bar or bridge, 6, into which a short upright tubular column or spindle, 7, is screw-threaded. The passage through said spindle has a contraction, 8, at its lower end, to permit the passage of only a small stream of water or air. Above said spindle is a vertically-expansible pressure chamber, 1 1, the lower wall of which is secured to said spindle and the upper wall of which is secured to the lower end of a similar upright tubular spindle, 9, seated in the valve, 5. Both of said walls are centrally open so that there is free communication from the condensation chamber through the spindle, 9, the pressure chamber, 11, and the spindle, 7. In other words, the

pressure chamber has an inlet through the spindle, 9, and an outlet through the spindle,

7. But, since, as already herein described, the lower portion of the spindle, 7, has the contraction, 8, it follows that the pressure chamber has an inlet larger than its outlet. In the upper end of the bore of the spindle, 9, is a valve seat, 10.

From the foregoing it will be seenthat there are two outlets through the cross-partition, 3, by which water and air may pass out of the condensation chamber when said outlets are open. As, already explained, the larger of said openings, 3*, may be closed by the valve, 5. which is through said valve, 5, may be closed by the float-controlled valve to be next described.

In the condensation chamber, the space above the crossartition, 3, is a float member, 13, on the ower portion of which is a valve, 14, adapted to rest on the valve seat, 10, when said float member is subjected to a temperature higher than the ordinary temperature of a room and when the amount of water in said casing, A, is not sufficient to lift or float said member. Whenever said valve, 14, rests upon its seat, communication between the condensation chamber and the interior of the pressure chamber, 11, is cut off. At the up or end of the float member, 13, is an upright stem, 15, which extends slidably through an-a erture, 16, in the open cross-partition, 18. Ilpon the upper end of the stem, 15, is a head, 17, which is adapted to support the float member, 13, under cer tain conditions as will be hereinafter described. Said float member is thermally expansible in the upright direction, in order that the distance between the head, 17, and the valve, 14, may be varied by thermal variation. One of the ways for making said member thermally expansible is to make it hollow, as shown in the drawings, one or both of the heads. being made flexible and the interior space being partially or entirely filled with a liquid, vapor, or gas adapted to expand under temperature higher than the ordinary temperature of a room and lower than the heat of steam, whereby said heads are, during the presence of suchtemperature, pressed from each other so as to effect a sufficient lengthening between the head, 17 and the valve, 14, to permit the latter to extend downward and bear upon the valve seat, 10. A conical screen, 19, rests upon the open The second of said outlets,

tition, the valve, 14, on the lower portion of said float member standing above'the valve seat, 10, and leaving passage for air and water through the spindle, 9, the pressure chamber, 11, and the spindle, 7, the contraction, 8, in the lower portion of the spindle, 7, allowing the passage of only a limited quantity of such air and water. Under such condition, the ressure in the condensation chamber, in tlie pressure chamber, 11, and in the space below the contraction, 8, in the spindle, 7, is substantially the same. If steam is now driven toward the pipe, C, and the quantity of air and cold water entering the trap as a result of such driving of steam is not in excess of the capacity of said contraction, 8, said air and water will flow through the spindle, 9, pressure chamber, 11, and spindle, 7, indefinitely. But if the uantity of air and water, or either, is more han will readily pass the contraction, 8, the chamber, 11, becomes filled with such water or air under pressure, whereby said chamber is expanded so as to lift the main valve, 5, from its seat and allow the passage of said air or water through said valve as well as through the valve, 14. And since the valve, 5, is much larger than the contraction, 8, there is a relatively rapid flow of air or water through said main valve, 5, and there may,

therefore, be such a rapid decline in pressure within the condensation chamber and the pressure chamber, 11, as to allow the latter chamber to contract and restore the valve, 5, to its seat, there to remain until pressure is again established in the pressure chamber in the same manner as has already been described. In this way the operation proceeds, the float member remaining suspended from the head, 17, and the valve, 14, being held above its seat and constantly allowing the passage of both air and cold water through the spindle, 9, pressure chamber, 11, and spindle, 7. But this condition changes when the cold water gives way to hot water and the latter, by its heat, causes the expansion of the float member, 13 to such degree as to cause the valve, 14, to press upon the seat, 10. Then the flow of water and air from the space above the valves, 14 and 5, is

entirely out off, for now both of said valves are upon their seats. Therefore the water will accumulate in the space above the crosspartition, 3, (the condensation chamber) and will continue to so accumulate until it has risen far enough around the float member, 13, to create a buoyancy sufficient to lift the float member, the stem, 15, sliding in the aperture, 16, until the valve, 14, is lifted sufliciently to permit the passage of water. Then such water flows downward through the spindle, 9, the pressure chamber, 11, and the spindle, 7; and if such flow is limited to the capacity of the contraction, 8, it continues indefinitely; but if the flow passing the valve, 14, is in excess of the capacity of said contraction, the pressure chamber, 11, becomes filled and expands sov as to raisethe valve, 5, from its seat and al-. low a relatively rapid flow of water through said valve. Thus the height of the water in the condensation chamber is rapidly reduced and the float member allowed to descend until the valve, 14, bears upon its seat, 10, whereby ressure in the pressure chamber, 11, is out o and the latter promptly contracts and allows the valve, 5, to return to its seat. Now both the valves, 14 and 5, are again closed, and they will so remain until the water in the condensation chamber again rises sufficiently to lift the float member so that the valve, 14, is again raised. The above supposes that the pressure above said cross-partition, 3, is greater than below said artitlon, and such is usually the case. Usua ly the pressure below said partition is very slight, and in some cases there is a partial vacuum below said partition. The float member always descends before all the water has escaped through the valves, 14 and 5; and therefore the two valves are constantly covered with water and thus sealed against the assage of steam. This is tobe regarded as tffe normal condition of the apparatus.

The expansibility of the float member, 13, is used after the operation has been estab lished,.after the passage of all the cold air and cold water. Then the-arrival of the hot water produces ex ansion of said member and such expansibi ity is then and thereafter used to cause the closing of the valve, 14, when there is an absence of enough water to bodily lift said float member. quantity of water is treated as abnormal and is at once reduced by flow through the valve, 14, and immediately thereafter also through the valve, 5. And it will be observed that the trap will always automatically open upon cooling of the apparatus. For if the supply of steam should cease and the water in the condensation chamber consequently become cool, the float member, 13, would contract and become sus ended by its head, 17, the valve, 14, being lifted from its seat and leaving a free passage for the outflow of such water through the pressure chamber. Then the apparatus is empty and not subject to freezing and consequent injury.

And such member, 13, and the area of the valve, 14, and the volume of the float member must be so proportioned as to cause sufflcient buoyancy before the float member is covered with water and the increase of buoyancy terminated. And it is to be observed that the area of the walls of the pressure chamber must be greater than the area of the main valve, 5, in order that the lifting power applied within said chamber may be greater than the downward pressure upon said valve.

I claim as my invention:

1. In a steam trap, the combination of a condensation chamber, a pressure chamber, said chambers being connected by a normally-closed valved passage the valve of which is submerged when closed and said pressure chamber having an outlet smaller than said passage, and a main valve located in the, wall of said condensation chamber and in operative relation with said pressure chamber for unseating by pressure of fluid flowing from said condensation chamber through said passage into said pressure chamber, a thermally-expansible float member in operative relation with said first mentioned valve to lift the latter from its seat when said float member is cold or when said member is floated by water in the condensation chamber and to press said valve upon its seat and close said passage when said member is heated and there is not suflicient water in the condensation chamber to float said member, substantially as described.

2. In a steam trap, the combination of a condensation chamber, a pressure chamber, a main valve in the Wall of said condensation chamber, a member supporting said main valve and joined to a movable wall ofsaid pressure chamber and having a valved passage communicating with said pressure chamber said pressure chamber having an outlet smaller than saidpassage, said main valve and the valve of said passage being normally submerged in water, and a thermally-expansible float member in operative relation with the valve of said passage to lift said valve from its seat when said float member is cold or when said member is floated by water in the condensation chamber and to press said valve upon its seat and close said passage when said member is heated and there is not suflicient water in the condensation cham ber to float said member, substantially as described.

3. In a steam trap, the combination of a casing, a horizontal partition in the lower portion of said casing, a main valve seated in said partition, a pressure chamber located within said casing below said partition and having an outlet, a spindle seated upon said pressure chamber and extending through said main valve and supporting the latter and having a valved-passage communicating with said pressure chamber and larger than said outlet, and a thermally-expansible float member located-above said partition in operative relation with the valve of said valved passage to lift said valve from its seat when said floatmember is cold or when said member is floated by water and to press said valve upon its seat and close said passage when said member is heated and there is not sufiicient water above said partition to float said member, substantially as described.

4. In a steam trap, the combination of a casing, a horizontal partition in the lower portion of said casing, a bridge below said partition, a main valve seated in said partition, a pressure chamber secured upon said bridge and having an outlet, a spindle secured upon said pressure chamber and extending through said main valve and supporting the latter and having a valved passage communicating with said pressure chamber and larger than said outlet, and a thermally-exp ansible float member located above said partition in operative relation with the valve of said valved passage to lift said valve from its seat when said float member is cold or when said member is floated by water and to press said valve upon its seat and close said passage when said member is heated and there is not sufficient water above said artition to float said member, substantia ly as I

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