US893529A - Trap. - Google Patents

Description

No. 893,529. PATENTED JULY 14, 1908; P. A. LITTLEFIELD.

TRAP.

APPLICATION FILED JULY 5, 1906.

2 $HEETS-SHBET l.

W iZIZ es ses Znvenior:

No. 893,529. PATENTED JULY 14, 1908.

F. LITTLEPIELD.

TRAP.

APPLICATION FILED JULY 5. 1906.

2 SHEETS-SHEET 2 r I an UNITED STATES PATENT OFFICE.

FRANK A. LITTLEFIELD, OF NASHUA, NEW HAMPSHIRE, ASSIGNOR TO NASHUA MACHINE COMPANY, OF PORTLAND, MAINE, A CORPORATION OF MAINE.

TRAP. I

Specification of Letters Patent.

Patented July 14, 1908.

Application filed July 5, 1906. Serial No. 324,739.

To all whom it may concern:

Be it known that I, FRANK A. LITTLE- FIELD, a citizen of the United States, residing .at Nashua, in the county of Hillsboro and State of New Hampshire, have invented an Improvement in Automatic Tilting Traps, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention relates to automatically operating steam traps of the type wherein the water of condensation is collected in a rocking receiver which tilts upon accumulating a predetermined weight of water, and by its movement actuates a valve or valves to effeet the discharge of such water In traps of this type the tilting movements are usually governed by a counter-balance lever conneoted at one side of its fulcrum to the re ceiver and having at the other side a suitable counter-balance weight. An objection to traps of this type as hitherto constructed, is that the packing employed to render the joints effective or tight seriously retards the movements of the receiver.

One of the objects of my invention is the provision of means to overcome this objection.

Another object is to secure quicker and more positive movement of the receiver while confining said movement to a smaller arc of oscillation than has hitherto been nec: essary, and still another object of my inventionis to provide a discharge valve operated by the tilting of the trap receiver which acts as a yielding buffer to cushion or check without substantial shock the movements of the receiver as it approaches either or both its positions.

These results are obtainable by the separate and conjoint action of a special construction and arrangement of counter-balance lever and the link which connects it with the receiver, by the employment of joints, which are rendered tight by the pressure of the contained steam or other fluid,

and by a valve having a stem which is yieldingly mounted to permit of sufficient vertical movement to open and close the valve and one which will not produce a friction. to re tard the movements of the receiver.

.All of the above, however, will be best understood and appreciated from the following description, when taken in connection with the accompanying drawings, of a trap embodying one form of my invention and selected for purposes of illustration, its scope being more particularly pointed out in the appended claims.

In the drawings :Figure 1 is an elevation of the left side of a trap embodying one form of my invention, and showing the receiver in vertical longitudinal section. Fig. 2, a vertical transverse section with parts broken away, taken on the line 2-2, Fig. 1; Fig. 3, a horizontal transverse section with parts broken away from below on the line 33, Fig. 1; Fig. 4, an enlarged vertical sectional detail, showing the construction of the discharge valve and its bonnet," and Fig. 5 a

front elevation with parts broken away of a modified construction, adapted for use as a return steam trap.

In the present embodiment of my inven tion, the trap selected for illustration is similar in shape and construction to that shown and described in my former patent #513,648, dated Jan. 30, 1894, to which reference may be made, if desired, for a more detailed description than is given here.

Referring to the drawings (see Figs. 1 and 2) a base or tripod, 1, of suitable shape and construction to support the various parts, is provided at one end with the tubular U shaped support, 2, upon which the tilting receiver or bowl 8, is mounted. The right arm of this support (Fig. 2) is provided at its head, 4, with a bearing to slidably receive a pipe, 5, constituting an inlet and communicating with the outlet of a steam heating or other system to be drained. A pipe, 6, is tapped into the head, 7, of the other arm of the U shaped support and communicates with the passage therein, said pipe, 6, constituting the outlet for the passage of water from the reservoir.

As herein shown, (see Figs. 2 and 3), the neck of the receiver, 3, is threaded to receive a T head or joint, 8, the arms of which are respectively formed to receive the inner ends of said inlet and outlet pipes, 5 and 6, said head and the pipe 5 being movable relative to each other and the stationary outlet pipe 6. To produce an efficient joint between said movable head, 8, and said pipes, 5 and 6, which constitute the support upon which it rocks, the inner end of each of these pipes is provided with a radially extended or circular flange, 9, and'the open and adjacent I the spring acting to withdraw said pipe and thus obviating the repeated adjustments netrunnion arm of the head is threaded to receive a nut, 10 shouldered internally to receive a packing ring, 11, of suitable material surrounding the pipe and interposed between said nut 10, and the pipe flange, 9, the nut being screwed upto retain the packing in place. By this arrangement either nut may be removed so that the pipe, 5, or the head, 8, may be slid horizontally to give direct access to and facilitate removal of the packing rings without having to resort to various expedients for picking it out as where a follower and locking nuts are em loyed. j Furthermore, as the trap is subjecte to the pressure of the contained steam or other fluid the latter acts upon the opposed inner faces of said flanges, 9, and tends to separate them, causing the reservoir head, 8, and the inlet pipe, 5, with its flange, 9, to slide to the right (Fig. 2), thus expanding or com ressing both packing rings against the shou ders of the nuts, 10, and effectively closing all opening or joints. It will be apparentthat the joints are thus packed or closed by steam or fluid pressure and that increase of the latter which had hitherto rendered joints less effective by my invention is made more effective.

For normally closing the joints when the trap is not under pressure, a coil spring, 12, surrounding the pipe, 5, is interposed between the head, 4, of said support, 3, and a collar, 14, adjustably secured on said pipe,

cause its flange, 9, to compress the package, 1 1. Simultaneously with this movement the reservoir head, 8, is drawn to the right, Fig. 2, to compress the packing ring on the pipe, 6, by the movement of the nut, 10, in engagement therewith, said pipe, 6, and its flange, 9, being stationary through the connection of said pipe with the head 7, of the U shaped support.

As will be apparent from an inspection of the drawings, see Figs. 2 and 3, the coil spring, 12, not only acts to close the joints when the trap is not in operation or subjected to steam pressure, but constitutes an effective means to take up the wear of the packing rings produced by the rocking of the receiver about its sup orts. It will also be obvious to those skillec in the art, that by this construction efficient joints are secured at all times, and that said joints are automatically maintained irrespective of wear cessitated by the employment of the usual type of followers and nuts to compress a packing with consequent retardation of rocking or oscillatory movements of the trap, produced by the frictional binding of the expanded packing, for by the present construction the trap continues to operate uniformly.

Through the adjustability of the collar, 14,

the tension of the spring, 12, may be varied to adapt it to different forms or types of packing or for other purposes.

The rocking head, 8, is provided with a central partition, 13 (Fig. 2), similar to that shown in said patent, dividing the head internally into chambers respectively communicating with the ends of the inlet and outlet pipes, 5 and 6, referred to. At the back of the outlet chamber, said partition, 13, has a threaded opening to receive the end. of a curved pipe, 15, the latter communicating with the interior of the reservoir or bowl, said pipe in invention being curved downwardly with its open end adjacent the lowest part of the bowl and acts as a siphon when discharging water from the reservoir.

For governing the movements of the receiver and for normally holding it elevated, a novel construction of counter-balance lever, 16, is employed which is connected at one end by means of an inwardly inclined link, 17, to an outwardly projecting ear on the free end of the receiver, said lever having at its opposite end a suitable counter-balance weight, 18.

The particular form of counter-balance that I have found most suitablefor traps of this type is formed with" a comparatively long and approximately horizontal arm upon which said counter-balance weight is secured and intermediate its ends is a depending V or elbow, the apex or edge of which rests upon a fulcrum or support, 19, formed by a depression in the top of a usual embracing yoke, 20, in which the bowl or receiver oscillates and is guided as shown in Fig. 1, the end of the lever that is connected with the receiver be ing inclined upwardly at an angle of about 45, and the link, 17, connecting its end with the receiver being inclined towards it. By this arrangement it will be noted that the positive moment of tipping which is equivalent or equal to the product of the combined weight of the lever arm and its counterbalance times the horizontal distance between their center of gravity and the fulcrum, will remain practically constant or decrease but slightly during the tipping of the bowl as the lever arm approaches a horizontal position as indicated in dotted lines in Fig. 1, or to express it another way, the eflective length of the lever arm upon which the counterbalance is supported remains approximately constant as said arm is elevated by the de scent of the receiver. negative moment or what may be termed the tipping moment produced by the weight of the receiver and its accumulated water will increase very rapidly as the upwardly inclined arm to which thelink is secured moves toward a horizontal position, or the effective length of this arm orthe horizontal distance between the fulcrum and the point of attachthe present embodiment of my.

Simultaneously, the

ment in the link will increase very rapidly. By this arrangement it will .be apparent that when the receiver has been filled to a desired height or holds agiven weight of water, according to the position of the counter-balance weight, the combined weight of the accumulated water and the receiver will cause the latter to rock to effect a discharge of its contents. To express this differently the negative tipping moment becomes greater than the positive moment of the counter-balance which normally prevents it, and as the tipping moment rapidly increases as described, the bowl will move rapidly until checked or retarded by the action of the discharge valve, presently to be described, as the bowl approaches its lowermost position. This negative or tipping moment of the receiver is still further increased by the inclined arrangement of said link, 17, the tipping of the receiver causing the latter to approach more and more toward a vertical position, thus increasing the downward pull of the receiver due to the weight of the receiver and its contents. l/Vhen' the receiver is emptied of its contents sufliciently to cause the counter-balance to elevate the receiver, the tipping moment of the trap, of course, operates in a reverse manner, said tipping moment decreasing very rapidly as the horizontal distance between the fulcrum and the point of attachment of the link decreases as its lever arm approaches a vertical position. The positive moment orv that due to the counter-balance remains approximately constant as before, the motion of the receiver being retarded as it approaches its normally elevated position, by the action of the dis charge valve. This arrangement of the counter-balance lever and 1ts link, 2, causes the simultaneous increase or decrease in both factors of the tipping moment while the counter-balace moment remains approximately constant.

To prevent the discharge of water from the receiver until such times as it has accumulated the predetermined weight of water, the passage in the U shaped support which cominunicates with the outlet pipe, 6, and the curved pipe, 15, is provided at its base with a discharge pipe, 21, having a valve 22, which is actuated by a vertical stem, 23, connected in a manner common to traps of this type and as shown in said patent, with a horizontally projecting arm of said head 8.

This valve is lifted by depression of the bowl or receiver to permit the escape of water from. the discharge end, of said pipe, the pressure of steam upon the surface of the accumulated water forcing or siphoning the water off through the curved pipe, 15, and its connections, through said discharge pipe, 21.

In the embodiment of my invention herein illustrated and as shown in Figs. 1 and 2, the

trap is adapted to discharge its contents against atmospheric pressure into a suitable tank or into any suitable device in which the contained pressure is less than that in. the trap. Obviously the condition under which it operates is that the pressure of the steam on the surface the accumulated water in the trap shall be sufficient to overcome the opposed pressure at the escape end of said pipe. The trap, therefore, is adapted for use wherever the pressure of said discharge end is less than that of the system being drained, hence the trap is suitable for use with any fluid such as the steam referred to and compressed air in which condensation takes place. The trap is also adapted for use as a water meter or elevator.

An important feature of my invention is the non-leakable frictionless oint of the discharge valve shown in detail in Fig. 4, and which, as already referred to, is constructed and arranged to act as a yielding buffer or cushion to check the movement of the receiver as it approaches the limits of its oscillations. This valve operates in a casing or bonnet, 26, having an external thread at its upper end to receive a head or cap, 27, centrally drilled to permit the valve stem, 23, to pass through, and having an inner rabbet or shoulder, 28, to engage or bear upon the upper edge, 29, of said bonnet and to clamp between it and said edge the outer edge or periphery of a flexible diaphragm, 30. The center of the latter is rigidly secured between the upper and lower sections of said valve stem, the diaphragm being perforated to re ceive a threaded end, 31, of the lower valve section which is tapped into the opposed head, 32, of the upper section of said valve stem, the opposed ends of the valve sections operating as a clamp to hold the diaphragm between them.

The outer and inner edges of the diaphragm being respectively and rigidly secured to the valve and its stem, there is no possibility of leakage between the parts, and the elasticity or flexibility of the diaphragm permits sufl1- cient vertical movement of the valve stem to raise the valve off of its seat, 33, upon the tilting of the receiver, but retarding the depression of the latter as it approaches the limit of its downward motion.

l/Vhen the counter-balance elevates the receiver, said diaphragm, 30, will yield sufficiently to permit the valve to be seated being flexed into position shown in Fig. 4, the elasticity, however, of the diaphragm checking the movements of the valve stem, and consequently of the receiver as it approaches its upper or elevated position. As the particular valve face and seat employed forms no part of my invention, it may be briefly described as comprising a series of threaded nuts and collars, one of which is secured to the lower section of the valve stem, 35, which is threaded at its lower end to adjustably receive the nut, 36. This nut has a recess or chamber at its lower face to receive a circular ring of rubber or other composition, 37, which is adjustably held in place by the clamping nut, 38, said ring being adapted to engage the valve seat to close the valve.

By reference to Fig. 4, it will be noted that the areas of the valve and the diaphragm are about equal so that the valve operates as a balance valve, the pressure of the steam or water having no effect upon the movements of the valve or the receiver.

As the steam actuated joint in the receiver head permits free rocking of the receiver without the usual frictional binding of the packing, and the counter-balance lever and water of condensation enters its link are adjusted to a nicety to cause quick positive movements of the receiver at the desired times, the provision of this flexible diaphragm for the valve, not only cooperates to retard the tipping of the trap as it approaches the limit of its oscillations, but perfects the organization by eliminating much of the usual or characteristic poundings and vibrations hitherto produced in traps of this character.

While the curved pipe, 15, is shown in Fig. 1, as bent downward towards the bottom of the receiver, the threaded engagement with the head. of the receiver permits it to be turned into an upper position, shown in dotted lines, Fig. 1, in which it is carried when the trap is used as a return steam trap. When so used, see Fig. 5, the pipe, 5, is provided not only with an inlet pipe, 40, with its check valve, 41, but with an outlet pipe, 42, and a check valve, 43, the check valve, 41, opening inwardly only, and the check valve, 43, outwardly, the escape pipe, 24, in this case, being connected with the boiler and having a relief valve, 34, as-in the patent referred to.

I/Vhile the operation of the trap will be understood with the description already given it may briefly be described as follows :-The the trap through its inlet pipe, 5, and flows into the receiver through the opening in its head, until the water has reached a predetermined height or in sufficient quantities to overcome the counter-balance weight. The instant this occurs, the trap tips and moves very rapidly owing to the increase of the tipping moment until checked by the operation of the diaphragm, 30, as the latter reaches the upper limit of its motion. By this movement, the valve, 22, is opened permitting the escape of water through the curved pipe, 15, the outlet pipe, 6, the passage in the tubular support, 2, the discharge pipe, 21, valve, 22, and discharge pipe, said movement being effected through the pressure of steam on the l surface of the accumulated water, which as stated, must be greater than that opposing its exit through said discharge pipe. The

curved pipe, 15, and the discharge pipes connected therewithconstitute and operate as a siphon to draw off the water. Simultaneously or immediately following the instant that the weight of the receiver with the water remaining therein becomes less than thatof the counter-balance, or when the tipping movement becomes less than that of the counter-balance, the latter acts to elevate the receiver in the manner already described. The decrease in the tipping moment, cooperating with the elasticity of said diaphragm,

30, to check the movements of the receiver as it reaches the upper limit of its movements as the valve, 22, is seated, thus avoiding the pounding of the valve upon its seat and the consequent wear produced thereby.

By the construction set forth a trap is produced that is thoroughly efficient, that operates easily, rapidly and in which the amount of oscillation hitherto required is very much diminished. By the construc tion and arrangement of the counterbalance lever the weight required is only about half that formerly employed, thereby decreasing both cost and wear of the parts. Further more the provision of my pressure actuated joints with the means for automatically taking up the wear avoids the necessity for adjustment or attention, and the construction of the joint is such that the-wear is reduced to a minimum but the effectiveness of the joint itself is increased by increase in the pressure of the contained fluid.

It will be obvious that my invention is not limited to the specific details or to the arrangement of parts herein shown for illustrative purposes only, but that the same may be modified and varied within wide limits without departing from the spirit thereof.

Claims.

1. In a trap of the type described the combination of a support, a receiver movablymounted thereon having jointed connection therewith, and pressure actuated means for effecting the closing of the joints between said support and receiver.

2. In a trap of the type described a receiver having a head mounted to rock about a horizontal axis and provided with joints between said head and the axis about which it rocks, said joints being automatically closed by the pressure of the fluid to which the receiver is subjected.

3. In a trap of the type described the com bination of a support, a receiver having a head movably mounted on said support, a joint effected by packing between said head and its support, and means for automatically taking up the Wear of said packing.

4. In atrap of the type described the combination of a support, a receiver having a head movably mounted on said support, a joint effected by packing between said head and its support, and yielding means for automatically taking up the wear of said packing.

5. In a trap of the type described the combination of a support, a receiver having a head pivotally mounted on said support, a joint effected by packing stituting the support about which it rocks, I

packing between said receiver and said pipes, and means operating automatically to expand the packing to close the joints between said receiver and said pipes.

7. A trap of the type described compris ingin combination a rocking receiver, pipes 001 municating with said receiver and constituting the support about which said receiver rocks, packing between said receiver and said pipes, and means operating automatically to take up the wear of said packing.

8. In a trap of the type described a re ceiver having a head, a pipe slidably mounted therein, packing between said pipe and head, means operating automatically to withdraw said pipe'to expand the packing thereby effectively closing said joint and taking up'the wear of said packing.

9. In a trap of the type described, a support provided with one or more hollow arms, a pipe fixedly secured to one of said arms and communicating with the passage therein, a second pipe slidably mounted 011 the other arm, a receiver having a head pivotally mounted on the opposed ends of said pipe and communicating therewith, packing on said pipes, means for retaining the packing in place between said head and said pipes, and means operating to withdraw the slidable pipe to close the joint between said head and pipes and said packing.

10. In a trap of the type described a support provided with one or more hollow arms, a pipe fixedly secured to one of said arms and communicating with the passage therein, a

second pipe slidably mounted on the otherarm, a receiver having a head pivotally mounted on the opposed ends of said pipe and communicating therewith, packing on said pipes, means for retaining the packing in place between said head and said pipes, and means operating to withdraw the slidable pipe to effect the closing of the packing oint and to take up the wear of said packing produced by the rocking of the receiver.

11. In a trap of the type described a rock ing receiver, a valve connected therewith to regulate the discharge of fluid therefrom, and a yielding diaphragm arranged to check the movements of the receiver as it approaches the upper and lower limits of its travel.

12. In a trap of the type described a rocking receiver, a valve connected therewith to regulate the discharge of fluid therefrom, and a yielding diaphragm arranged to check the movements of the receiver as it approaches the upper and lower limits of its travel, said diaphragm having means operatively conbetween said head I nected therewith for adjusting its position to vary the retardation produced upon the movements of the receiver.

13. A trap of the type described comprising in combination a rocking receiver having a counter-balance lever to govern its movements, a pipe communicating therewith provided with a valve bonnet, a valve therein,

having a valve stem operated by the rocking of said receiver to govern the discharge of fluid therefrom, and a yielding diaphragm seated by its edges in said bonnet and centrally connected with said stem to form an impervious joint between said stem and bonnet.

14. A trap of the type described comprising in combination a rocking receiver having a counter-balance lever to govern its movements, a pipe communicating therewith provided with a valve bonnet, a valve therein, having a valve stem operated by the rocking of said receiver to govern the discharge of fluid therefrom, and a yielding diaphragm seated by its edges in said bonnet and centrally connected with said stem to form an impervious joint between said stem and bonnet and to retard the movement of the receiver in seating said valve.

15. A trap of the type described comprising in combination a rocking receiver having a counter-balance lever to govern its move ments, a pipe communicating therewith provided with a valve bonnet, a valve therein, having a valve stem operated by the rocking of said receiver to govern the discharge of fluid therefrom, and a yielding diaphragm seated by its edges in said bonnet and centrally connected with said stem to form an impervious joint between said stem and bonnet and to retard the movements of the receiver as it approaches the limits of its travel.

16. A trap of the type described comprising in combination a rocking receiver, a pipe communicating therewith having a valve stem actuated by movements of said receiver to effect the discharge of fluid therefrom, and joint means carried by said stem arranged to check the movements of the receiver as it approaches the limits of its travel.

17. A trap of the type described comprising in combination a rocking receiver, apipe communicating therewith having a valve stem actuated by movements of said receiver to effect the discharge of fluid therefrom, joint means carried by said stem arranged to check the movements of the receiver as it approaches the limits of its travel, and a coun- -terbalance lever to govern the movements of the receiver.

18. A trap of the type described comprising in combination a rocking receiver, a pipe communicating therewith having a valve stem actuated by movements of said receiver to efiect the discharge of fluid therefrom, and joint means carried by said stem arranged to check the movements of the receiver as it approaches the limits of its travel, said means comprising ayielding diaphra m connected with said stem and with the vaIve casing and permitting of slight movement of the stem relative to said casing to permit opening and closing of said valve.

19. In a trap of the type described a sup ort, a rocking receiver, an angular counterbalance lever to govern the movements of the latter provided with a horizontally arranged arm for a counter-balance weight, and a depending elbow or V, the apex of which rests upon said support, and a link connected with said receiver and with the adjacent arm of said elbow.

20. In a trap of the type described, a rocking receiver, and a counter-balance lever to govern its motion having an angular bend intermediate its ends to raise the active point of said lever above its fulcrum, said lever being constructed and arranged to cause rapid variations in the tipping moment upon the tilting of said receiver, the moment of the counter-balance arm and its weight remaining approximately constant thereby effecting rapid movements of said receiver.

21. In a trap of the type described, a rocking receiver and a counter-balance lever to govern its motions having an angular bend to raise the active points of said lever above its fulcrum, said lever being constructed and arranged to cause a rapid increase in the tipping moment upon the tilting of the receiver to discharge its contents and a rapid decreaseupon moving in a reverse directlon, the moment of the counter-balance arm and its weight remaining approximately constant, said moments causing rapid movements of said receiver.

22. In a trap of the type described, a rocking receiver, a counter-balance lever pro vided with a weight to govern its movements, an inwardly inclined link connecting said receiver with said lever and a support or fulcrum on which said counter-balance lever is mounted, said lever having a depending elbow or V intermediate its ends, the apex of which rests upon said fulcrum and the outer arm of said V being connected with said link, the angular arrangement of the lever elbow and the link connected therewith cooperating to effect a rapid variation in the efiective leverage or tipping moments and to cause rapid movements of said receiver. 1

In testimony whereof, I have signed my name to this specification, in the presenceof two subscribing witnesses.

. FRANK A. LITTLEFIELD. Witnesses:

JOHN R. SPRING, ETHEL L. SMITH.

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