US1859089A - Valve - Google Patents

Description

May 17,1932. F1 T. HOLMES 1,859,089

VALVE K Filed Aug. 15, 1929 l 2 Sheets-Sheet l il Mill/1119x0111@ `I s lll-.lll

32225 l 'Nm- .By ,W IKM.,

ATTORNEYS.

-Z/ v /50 V May 17, 1932. F. T. HOLMES 1,859,089

VALVE a Filed Aug. 15, 1929 2 sheets-sheet 2 INVENTOR.

By W1/1PM ATTORNEYS.

'rhANxLm T. Homme, or sr Patented May 17, i932 ori-'icaN UNITE S UGTB, INC., F WEBTFIELD, H

VALVE mamon mea ausm is. was. semi no. 386,077.

This invention relates to improvements in pressure regulating valves, suph as are used for reducing the high pressure in a gas or liquid main pipe line to a lower consumption pressure.

A common principle .used in these valve types and also useolin my novel design is the coaction of diderential pressure areas with adjustable spring means for opening and closing the valve in a predetermined manner for automatic pressure regulation. In many constructions used heretofore, there have been provided as a low pressure area either the area of a plunger or of a diaphragm. Each oi these two means has its advantages and disadvantages.

According to one feature of this invention, l provide a novel means to overcome some disadvantages in each of the formerly employed elements by forming the low pressure area as a combination plunger-diaphragm, whereby at the same time further advantages not possessed by the prior construction are obtained. Still other features in my` novel design will appear from the subsequent specication and claims.

ln the drawings:

Fig. l is a vertical section on thev line of symmetry of the valve and its pipe line connections Fig. 2 is a vertical section on the line of symmetry but at right angles to the section inig. l and with some parts shown in side elevation;

Fig. 3 is an enlarged view of the combination4 plunger-diaphragm and the elements directly connected to it or coacting with it; and

l? ig. i is a detached section of the plungerdiaphragm on a larger scale and with some dimensions distorted.

.l shall rst give a general description of the structure and its mode of operation without particularly pointing out its novel features, itl order to facilitate the understanding of t e import of the modifications which form the substance of this invention and are dealt with later on. y l .Thelvalve casing 1 is cast integral with the inlet and outlet flanges 2 and 3, respectivelyf and with the interior downwardly discharglng fluid admission channel 4 Which terminates in a valve seat support 5. lThe comparatively short cylindrical casing houses the plunger diaphragm 80 and serves as the low pressure expansion chamber. This chamber body is screwed to the top flange 6 ofthe valve casing with the marginal ortions of the plunger-diaphragm clampedp between by means of a Wrench engaging flat vfaces provided on an upstanding flange portion 23 of the casing. The casing of the eX- pansion chamber carries the top cap `30. The bottom of the valve casing is formed by a separate bottom cup connected by threads.

Supported in the middle of the diaphragm the vertically extending valve operator consisting of the two screwed together members and 60 with the plunger-diaphragm,

clamped betvveen7 is free to perform limited vertical movements for operating the valve. y

ing of the valve. lt will also be apparent now that this valve operates onl the known principles ofsuch .valves in as far as there are provided four active forces for the valve operator: an opening force from the high.

pressure side on the valve disk; a closing force from the lovv pressure side on the plunger-cliaphragm; and two oppositely directed adjustable spring forces. The amount of pressure reduction is determined by the ratios of the eective areas of the valve disk and the diaphragm of which the latter is, of course, the larger one, and by the adjustment of the spring pressure which will either accelerate or retard an opening tendency from thedierential pressure areas. l l

I shall now give a more detailed description of the valve operation and the parts coacting withjit and, at the same time, particuv of the yoke with the help o receiving and guiding a stem portion 56 depending from the valve disk 51 so that the valve operator is accurately guided and downwardly limited in its movements. To yfacilitate the attachment or removal of the bottom cup 40, its outer portion is provid-4 ed or corrugated portion comprising two oped with nut faces 42.

The valve disk 51 is`rigidly fastened by threaded engagement to the rin portion 52 f t e nut faces 53. lBefore screwing the valve disk in its attachment ring, a Hat flexible "platea 54, preferably made of rubber or some composition of it, is put on topof the disk, which plate will after assemblage be clamped between the annular flange 57 of the yoke ring and the valve disk andl provide a tight seal for the valve. The seat of the valve may either be directly formed on the lower portions 5 of the interior fluid channel 4 by grindingan annular portion about the channel orifice, or" 'by provlding a detachable seat member screwed in the orifice asshown in the draw ings at 7.

` The upper end .of the yoke has the shape of a plate with threaded central aperture for ,receiving the threaded reduced end 63 of the hollow spindle 60. This reduced end is vsutiiciently long to vpermit the accommodation between the screwed .together spindle and yoke of the plungerdiaphragm assembly.

This assembly comprises, as can best be seen from Fig. 3, the plunger-diaphragm --proper vpreferably formed from rubber or som'e suitable rubber composition, two comparatively thin and centrally apertured metal disks'81 and 82 holding the diaphragm `clamped between them, and an upper washer disk 84 which seals the whole assembly so that no fluid can pass from one side .of the plunger-diaphragm to the other. The upper clamping disk 82 has the same diameter as the outer upper plunger portion 85 of the diaphragm, while the lower disk y81 is of somewhat smaller diameter to fit into the interior of the cup-shaped plunger-diaphragm structure.' This inner disk is insertul in the ready shapedf cup and when once inserted will remain therein and form. in connection with the rubber structure, the

l finished construction. Since the metal disks may be regarded as rigid with respect to the pressures emplo ed, the upper clampedbetween portion o the rubber-diaphragm v will remain undeflectedA and, therefore, .inactive in the operation of thediaphragm. The lower marginal portionsv 86 of the plungerdiaphragm are clamped between screwed to- 'getherfiiange portions 6 and 21 of the valve `casing and cylinder, respectively. A washer ring 874is added to insure a fluid tight/'seal between the casing and the cylinder 'and to prevent rumpling ofthe diaphragm by tor- I sional forces while it is being screwed down on its marginal seat portions. The lower mar inal and the upper inflexible portions of t e` plunger-diaphragm are connected by intermediatel portions (see Fig. 4) which, in

cross section, present an upper vertically extending plunger portion 88 and a lower pleatyoke 50, is transmitted to the movable valve g plate.

l Beforel stating thev advantages` incor-` porated in this combination design `of a plunger-diaphragm, I shall first describe another feature of this design which is only schematically indicated in Fig. 4 by two rows of short strokes disposed along the section of the revolutional surfaces aff-b of the inside and c--d of the outside of the plungerto represent a fine fabric of cotton or the diaphragm. Thetrokes or dots are meant like, which is superficially but inseparably impressed in the rubber material. The threads of' this fabric project suiciently from the rubber surface to prevent a close contact between lthe rubber material and adjacent metallic portions such as the cylinder walls. In other words, the plunger diaphragm has a fabric and not a rubber contact with the cylinderwalls. The fabric is carefully joined to the rubber so that the latter does not penetrate through to the contacting wall surface.` This is an important feature when there is contact with the cylinder walls. A combined surface layer is inv dicated in Fig. 4 between the points a and b for reinforcing the bending or critcal flexing zone of the plunger-diaphragm.

The outside fabric or lining fulfills three purposes. It eliminates the sticking of the y plunger-diaphragm to adjacent metal parts, especially to the cylinder walls. It -is a known fact that rubber faces, when noperative and in contact with metal parts such as brass for a long. period almost amalgamate with such parts so that upon renewed operation a prompt action of the valve cannot be relied upon because of sticking between metal Vand rubber, and partial disintegration of the rubber. bet-Ween the cylinder walls and the operatng plunger is appreciably reduced in a fabric` metal contact as compared to a rubber-metal contact. s

Furthermore, the friction The -third purpose of this outside imresure ofthe hi h ressure side. The be- Y pressed fabric as Well as the inside fabric is to reinforce certain portions of the corrugated side wall sections of the lunger-diaphragm in a manner similar to t e reinforcementl of tires by fabric plies at critical bending zones. These reinforced portions will withstand wear toa greater extent and also, due to their greater stillness, divert the bending strains to the -unprotected and more easily yielding portions so that by'distributinv the strains over a larger part of the bendabIe material a'rupture from wear will not occur so quickly but when it does it will occur in the section between the points b and e Where, accordin to my novel arrangement of plunger-diap ragm construction, it will do the least possible harm.

I shall presently give a short account of the advantages that accrue from the features of my desi under the various possible operating con itions.

As long as the plunger-diaphragm is intact it o rates on the pure diaphragm principle. (giving to the flexible and corrugated 'side walls of the diaphragm which actually i supply the axialexpansion of the diaphragm e a much greater displacement'is obtaina from this diaphragm than from the usual plain diaphragm of like diameter. Without increasing the dimensions of the valve, it is, therefore, possible to provide a much greater lift of the valve disk so that for the same capacity of owl smaller valves are obtained, a feature which is es cially valuable in all cases Where such va ves have to be installed in narrow or overcrowded locations. Also, one and' the samevalve model canbe used for a wider variety of volumetric conditions. The ordinary diaphragm permits pressure reduction only to a limited degree withqa given set of s rings while the plunger-diaphragm of this construction covers' a corn-l paratively wide range without requiring-different springs, and this is due to. its much greater stroke. The plunger-diaphragm combines, therefore, absolute tightness with the favorable operating characteristics of a plunger operated valve.

A great `disadvantage ofthe ordinary disk diaphragms is that they easily wear near the edges of the metal parts between which they are clamped, since the strains of deiection are almost exclusively concentrated in` those portions, and that, if a break occurs, it will usually, due to the strong shearing forces in such diaphragms, seize ar complete circumference and thus separate the central portion from the marginal portions 4.conipletely. The. result is that a high pressure surge of considerable destructivev energy is released upon the distribution system which may cause considerable damage in that system. At all events, following a rupture, the low pressuresystem will come under the full behavior of e ectric distribution transformers without safety devices in which the high voltage insulation has broken dowh and given way tothe high voltage so that it sudenly rushes into the distribution system.

In my plunger-diaphragm, a sudden com- I plete rupture 1s muchl less liable to occur low pressure side. In this connection, thedesirability of having exact stops for the stroke of the valve operator becomes, apparent. In former constructions the down-v ward stroke was checked by the upper slantavior of plain iap ragm operated valves A y in case of diaphragm rupture resembles the v imv ing Wall portions of the inner fluid access channel. rough means of limiting `the stroke. In the present construction, the closing stroke is defined by the valve seat and the openingpstroke bythe bottom cup. Both parts are accurately machined, and the stop position of the bottom cup may furthermore be adjusted by its threads.

The only difference in the operation of the severed plunger and the intact structure is that the plunger permits a small quantity of the fluid to leak past its sealing faces. This is aproperty which I have found to be highly desirable and which, for this reason, I even further to a certain degree. Such valves are frequently installed in places where no attendant is present and where inspection is only rare and occasional. the defective condition of the valve long be'- fore a dangerous break-down can arise is almost imperative under such circumstances,

and this indication is furnished in my structure by a slight leakage which may continue for months` after* the rupture without involving any real danger.

This desirable leakage is another reason why I prefer to cover the outside faces ofthe plunger-diaphragm with a fabric. This mesh fabric of specific, suitable kind and combined with the rubber surface layer in a specific way offers a wrinkled or non-smoothbearing surface of relatively very limited extent to the contacting cylinder walls and,

consequently, does not tightly seal the expansion chamber.- This is particularly so if the plunger is guided withinA the cylinder This, of course, represented only a An indication of i to be understood that my without appreciable bearin ressure and,

for this reason, I prefer a li t contact between the plunger and the en osi'ng walls.

After having described the preferred construction of my combination plunger-'dia'- phragm and t's various advantages, I wish it inventiongneed not be carried out in exact y the same manner as exemplified before. Any mechanical conibination of a'plunger and a diaphra m so arranged that the plunger will rea ily ltake over the function of the diaphra m. after its partial or complete rupture and t us prevent the disturbance or interru tion of the low pressure service, will lie within the sco e of my invention. I might, for instance, c oose a greater number of bends in the corrugated side walls instead of only two, or go to the other extreme and combine a plain disk diaphragm with a plunger as second member.

The top cap is attached to an upstandl ing' lian e 23 of the expansion chamber in a iiuid-tig t manner by threaded engagement and furtherby a lateral ange 31 on the cap with washer ring seal 32. The combined volume of the expansion chamber and the top cap is ample to provide the necessary breathin regiments, therefore, an additional or, better,` a secondary protection if a timely replacement of the defective plunger-diaphragm should have been overlooked and also the 'severed plunger should have become worn toa considerable measure. 'Ihere is, however, sufiicient crawling for small amounts of leakage water to appear on top of the cap and disclose the defective valve condition. Such crawling passage may, of course, also be provided in any other suitable manner. The adjusting screw 33 presses on the head plate 34 of the interior spring and thus permits the adjustment of the tension in that spring. The tension of the outer spring 62 is adjusted by the nut 35 which travels up and down on outer spindle threads. Y

' The yoke and the carrier for the valve disk are made integral and, after the rubber disk has been attached in the manner described above, the whole structure is then assembled in the place shown by swinging over the inlet passage. Space for this is provided in the casing extension in line with the inlet passage.r Except for 'this extension, the valve casing is symmetrical and. as shown in the figure, makes a neat outside form appearance with small bulk and with all parts of the valve very easily assembled.

What I claim is:

1.r The combination with a pressure regulating valve comprising a valve, a valve operator, a low pressure expansion cylinder and means'for limiting the stroke of the valve operator, of a plunger-diaphragm connected air for the diaphragm. ThisV top cap assage lefty along the threads of the adjusting screw 33 in marginal portions to the cylinder for i tightly sealing the same and in central portions to the valve operator for actuating the valve, and having ex ,ansiblecorrugatedl intermediate portions or axial expansion in artial contact with the cylinder walls, said -V intermediate ortions also containing circumferential sections of lesser resistance to wear for said plun er-diaphragm to act in said cylinder as a iaphragm of relatively great stroke in non-worn condition and as a plunger of like stroke if partly or completely ruptured in said lesser resistance sections.

2. A valve with pressure expansion chamber and a plunger-diaphragm o erable therein, the latter consisting of a iaphragm, a plunger with leaking seal, and ofvconnectingv means between the two with lesser resistance to wear, for said plunger-diaphragm to act in said chamber as a diaphragm in nonworn condition and as a leaking plunger seal, said fabric covering being interruptedg in circumferential sections of said intermediate plunger-diaphragm portions for making such unprotected portions sections of lesser resistance to wear.

4. In a pressure regulator structure, a combinedplunger head and diaphragm member comprising a horizontally arranged disk to act as a plunger head having a circumferential extension depending downwardly, then axially and then downwardly again and then outwardly into final horizontal annular form to serve as a diaphragm anchor, said member being formed of an elastic body material including vulcanized rubber, rigid plate imembers above and' below the upper horizontal disk portion as an unbendable' piston head, fabric fastened smoothly over the outer surfaceof said extension through its curved portions, and a fabric covering fastened along the lower insidesurface and extending from under one of said rigid plate members as far as the extent of the first bend from the horizontal to the vertical portion so as to bridge with a stiifening layer that portion of the body material as it may bend between the rigid plate members and the lower part of the extended body portion, whereby the region of greatest bending strain is distributed over a larger area, the outer wall of said disk bein arranged parallel to the axis .for at least t e thickness of the disk, whereby the disk may t a pressure cylinder as a plunger and its extension may act as diai phragm along with the plunger portion. y

In testimony whereof I have aixed my v signature.

FRANKLIN T. HOLMES.

Images