US2518894A

US2518894A - Automatic changeover mechanism

Info

Publication number: US2518894A
Application number: US599486A
Authority: US
Inventors: Frank F Humbarger; Ralph C Pierson; Willis G Schepman
Original assignee: Union Carbide and Carbon Corp
Current assignee: Union Carbide Corp
Priority date: 1945-06-14
Filing date: 1945-06-14
Publication date: 1950-08-15
Anticipated expiration: 1967-08-15

Description

' AUTOMATIC CHANGEOVER MECHANISM Filed June 14, 1945 W 12 I V 5 1 11% A /5 B :30 (735/619 NvENTbRs Y l9 v A FRANK HUMBARGER a A K RALPHYCLPIERSONU .WILLISG. SCHEPMAN IATTORNEY,

nomical and practical means of insuringa con-' Patented Aug. 15, 1950 2,518,94

UNITED stares rnrsm orncs 2,518,894 ,evf oMei-" g-ci em vm MECHANISM Frank F. Humbarger, United States Navy, Ralph C. Pierson, Indianapolis, and Willis G. Schepman, Speedway, Ind., assignors to Union Carbide and Carbon Corporation, a corporation of New York Application June 14, 1945, Serial No. 599,486

- 10 Claims. '(01. 137-144) maintaining one of two regulator springs ina less-compressed state (reserve side). The ends 1 This invention relates to an automatic servicereserve changeover mechanismwhich is adapted to maintain an uninterrupted supply of fuel gas of the interlocking bar are tapered and the disto the consumer by automatically changing the tance between them is longer than the face-tosource of gas from service to reserve when the .--;;'face distance between two push rods, so that the service gas supply has been withdrawn. bar is forced by the other regulator spring into Originally, liquefied petroleum gas systems, a groove in the push rod being depressed to load for example, were all non-automatic, and when its spring; thus relieving sprin pressure on such the service gas supply cylinder was emptied it other push rod, and thereby causing the lat was necessary for the customer to gooutdoors waiter to be released from its depressed position. and turn on the reserve supply of gas. Since Referring to the drawing: the customer had to be educated to the opera- Fig. 1 is a fragmentary view in front elevation tion of the cabinet and had to depend 'upon himof a distribution system exemplifying the invenself for the control of thegas supply, the need tion; and for an automatic changeover mechanism became 154! Fig. 2 is an enlarged View in section taken on imperative, This need increased with the advent line 2-2 of Fig. 1, showing details of construction of the use of'liquefiedp'etroleum gas forrefrigei of the changeover mechanism. ation, automatic water heating, etc; The auto- The system shown in Fig. 1 comprises a pair matic changeover mechanismwas desirable since of gas containers such as cylinders 3, one of it overcame the disadvantages associated with "which constitutes a service source of gas supmanually changing the supply byproviding uhply and the other, a reserve source of gas supply. interrupted service. The cylinders 3 have their cylinder valves 4 con- The main object of this invention is to provide nected by pipes or leads 5 to a changeover mechaan improved service-reserve changeover mechanism'M which is described below in detail. A nism that is fully automatic, providing eco- 25 signal gauge S is connected to the device M by a pipe 6. Also connected to the manifold is a stant or uninterrupted supply of'gas in a; dualservice regulator R the gas outlet of which is consource liquefied petroleum gas distribution sysnected to an appliance such as a stove, by a tem. Another object is to provide a fluid districonduit 1. 19 1 ys m Changeover mechanism that is 0 The changeover mechanism M, as illustrated safe, efficient, compact, simple and effective. in Fig. 2, comprises two gas inlet passages A, two According to the invention, "there is provided gas pressure chambers B, a gas outlet C, a signal an automatic changeover mechanism for liquegauge outlet (not shown), a, lower valve body E, fied petroleum' gas distribution systems, which an upper valve body F, and two spring chambers comprises two supply regulator valves, one for" 5 '-I-G. Since both sides of the device M are similar, e serv ce as Sou ce andtheother for the i' for brevity and clearness, only one side will be serve gas source, operative automatically to described below. maintain an uninterrupted supplyfoi gas when The gas inlet passage A is internally threaded. the pressure of the service gas source falls to'a at I!) and is provided with a nozzle N having an predetermined value.- When'thegas' in the sew: 0 enlarged gas inlet passageway portion l2 and a ice source falls to such value, the changeover reduced portion l3. The gas inlet passage A is mechanism automatically changes the system formed in an integral portion of the lower valve over to the reservegas source. The changeover body E in any suitable manner, such as, casting, mechanism does not p al 11111161 l y d machining, or a combination of such operations, pressure. That is to sayj the' supply regulator 5 whereas the nozzle N is an insertof the gas inlet valves operate to reduce 'the' ga's pressure to" passage A. which the regulators are "subjected" by" closing The gas pressure chamber B is bounded by the the valves automatically'in response to certain gas inlet nozzle N in the gas inlet passage A on gas pressures whichare lowcompared to 7 full the gas inlet side, It is bounded below by the cylinder pressure; Further, according to the 50 'lower valve body E, which is also a portion of invention, anovel service-reserve alternating the side of this chamber B. Above, it is bounded ec a ism is provid d a i "a interlockin by a flexible diaphragm 14. On the gas outlet bar that only allows one gas source to be connected in reserve at a given time. leads to the gas outlet C and signal gauge outlet Such mechanism provides positive means for lis -(not shown) The gas pressure chamber B consideit is bounded by a gas passageway l5 which 7 tains a valve seat is, composed of suitable resilient material, which is capable of making contact with the gas inlet nozzle N and is part of a pivoted valve seat holder IT.

For the diaphragm and valve seat, any comparatively resilient material may be-used that is not soluble in liquefied petroleum gas, such as propane, for example, in either the liquid or vapor states, and also is relatively unaffected b tem-- perature.

The valve seat holder I1 is actuated by'a lower diaphragm plate is about a fulcrumpivot- IS. A lever arm 26 is rigidly connected: to the valve seat holder [1. The lever arm 29 extends through and is freely movable relatively to-aperture" 2t that is formed in a portion of the lower diaphragm plate [8. The aperture 2! is conicall counterbored at its opposite ends to leave an intermediate aperture portion slightly larger in cross-- section than the lever arm 28, and to provide a knife edge that engages the lever arm 2-92 The: arm 26 is movable through the. lever opening 2-! when the lower diaphragm plate I8 is acted upon. by the flexible diaphragm M. The valve seat holder I! is pivotally attached'to an elevated portion 23 of the lower valve body E. This-arrangement minimizes humming, which greatly lessens. the life of: the valve, and also produces a more constant flow of gas.

A diaphragm screw 26" holds the lower diaphragm plate I8 in the center. of the: upper wall of the gas. pressure chamber. B and in contact with the flexible diaphragm: l4; opposite. an upper diaphragm and lower spring plate 25, forming; a gas-tight seal.

The flexible diaphragm member. is secured il'il gas-tight relation between flat rim portions 26- and 21 of the lower valve body E and upper valve body F, respectively, by screws 28. The flexible diaphragm member. thus-acts as a gasketbetween the valvebodiesE and F.

Gas outlet passage [5 connects the gas pressure chamber B to the gas outlet (3 and: signal: gauge outlet passage. The gas outlet 0' is at one end of the connecting passage and the signal gauge outlet at the. other. The gas outlet C'is-connected to the regulator R by acoupling 8;, and the signal gauge outlet is connected to the signalgauge S by the pipe 6.

The spring chamber G is bounded on. the sides by the upper'valve body 1?, on the: bottom by the flexible diaphragm M, and on the top by a push rod 29. The spring chamber G contains at least three ribs 38 which are a portion of the upper valve body F and serve as guides for a va-lvespring 3 I. The valve spring 3| presses against the'plate- 25 at its lower end; whereas the upper end of the spring is in contact with" an upper vaive'plate 32 which thereby is heldagainst a pressure adjusting screw 33. An elastic lock-nut 34 or other suitable means retains the pressure adjusting screw 33 in its adjusted position, and is incor porated in the hollow push rod 29. The screw 33 is mounted on the inside of thepush rod. for adjustment to determine the upper operating pressure on the diaphragm I4 when the spring 3.! is compressed.

A ring 35 is threaded inside of the body F, pr0- viding a stop which engages an annular shoulder 44 on the rod 29 and thus limits the outward movement of rod 29 by the spring 3 i, so that adjustment of the screw 33. determines the lower operating pressure of the spring when the rod 29 is released. The ring 35 also acts as part of the guide for the push rod 29.

A push but on 3 i I attached to the push rod 29 by suitable means such as a locking pin 31. The push button 33 closes the upper end of the rod, so that the screw 33 is not readily accesible. An interlocking bar 38 having rounded ends is disposed in an interlocking bar cavity or way 39in the body F. The bar 38 is slightly greater in length than the faceto-face distance between push rods 29, so that one end is located in a groove 40 of the compressed push rod when the other end is in contact with the surface outside of the groove in the other push bar. Av cap ll is provided for an opening through which the interlocking bar 38 is moved when the. parts of changeover mechanism M are'being assembled.

Small air vents or holes 43 are provided in the wallv of the upper valve body F,-so as to maintain atmospheric pressure on the upper side of the diaphragm Hi.

The illustrated changeover mechanism M thus consists of two" interconnected gas supply regulators'K, one for the service gas source and the other for the reserve gas source. Either regulator may be made the service side by depressin a push button 36; which automatically makes the other one the reserve side. The interlocking bar 38 is shifted by the force of the other spring 3|, acting through its push rod 29 and groove 59 on the rounded end of the bar, and thus latches the selected supplyregulator in adjusted position, when the groove 40 of the selected rod is presented to the other end; of the bar 38. Because of the compressionof thespring-3-E, the gas supply regulator; which operatesat a lower gas pressure, automatically meets the demand for gas from the service cylinder; The signal gauge S which works on the pressureidifierential between the service and: reserve sources, indicates when the service gas supply container has been depleted.

When the-service gas supply container has become depleted, the other gas suppl regulator automatically meets the demand for gas from the reserve cylinder. The automatic changeover mechanism occurs by virtue of the fluid pressure in conjunction with the different compression loads on the springs 31-. The more compressed spring 3| causes the regulator valve controlled by such spring to operate first, and when the gas pressure falls sumciently, the less compressed spring 3! automatically causes its valve to operate. When the gas pressure in either chamber B reaches the value at which the springs 3| are set, the corresponding valve is automatically closed, so that the supply of gas is pres sure regulated first by one supply regulator (service) then by the other supply regulator (reserve). When the reserve; regulator valve remains closed, the-service regulator operates; and when the reserve regulator is in operation, the service regulator valve remains open.

The signal gauge S may be merely a pressure gauge whose face has been blanked oh and a red portion is put on the gauge dial which is set to' show redwhen the automatic changeover mechanism is operating on the reserve cylinder. Thus, the consumer notifies a service man that he is now using the reserve cylinder. When the service man replaces the empty cylinder, he reverses the positions of the push buttons 36 by simply depressingthe reserve push button and thereby the former service side becomes the new reserve side.

Since the device lVL may be used with a conventional signal. gauge S, the gas supply regul'atorsKarefsetat approximately 16 p. 55 i. and approximately 9 p. s. i., for service'and reserve operation, respectively. If other operating conditions are to beimet pressure regulation'can be made.

The changeover mechanism M has sufiicient capacity, when coupled with a service 'regulator R, that reduces the pressure to approximately ten inches ofwater column pressure and isused in almost all. propane distribution systems, to provide fifty cubic feet per hour, or enough capacity to provide a three-cabinet installation (two cylinders each) per automatic changeover mechanism M and service regulator R. It will be evident that details of the disclosed constructioii may be varied, and certain features may be utilized independently of others, without departing from the principles of the invention.

While the invention has been described in connection witha gas, it will be understood ,thatthe invention is not limited thereto, but may ,beused in connection with aliquid, and the term"fluid in the claims is intended to include liquid as well as gas.

We claim:

1. An automatic service-reserve changeover mechanism for dual-source fluid supply systems, comprising a pair of fluid supply regulators including differently loaded springs, and means for alternating the loads on said springs comprising push rods, each provided with exposed manually engageable means in line with the major axis of the corresponding spring and latch means acting by virtue of the force of one of said springs automatically to release one push rod and latch the other push rod when the latter is pushed to load its spring.

2. An automatic service-reserve changeover mechanism for dual-source fluid supply systems, comprising a pair of fluid pressure responsive regulators adapted to operate at difierent fluid pressures, so that one regulator operates until the service fluid source is depleted, whereupon the other regulator is caused to operate, each of said regulators comprising a regulator spring, a push rod opposing the force of said spring, and a push button on said push rod, and a common latch for said push rods, the arrangement being such that a selected regulator is loaded by pushing the push button to move the push rod longitudinally directly against the force of the spring until said latch operates automatically by virtue of the force of the other spring to secure the push rod in loaded position.

3. In combination, a pair of compression springs, spaced parallel manually engageable push rods for selectively adjusting the force of said springs, said rods having grooves, and a cross bar having ends disposed between said rods, the length of said bar being such that one end fits the groove of one rod when the other end contacts the surface outside of the groove of the other rod, said grooves being positioned so that pushing one push rod directly against the force of its spring moves the groove of that rod into line with said bar, causing the other spring to force its push rod to shift said bar out of the groove of the latter push rod, and into the groove of the pushed push rod, thereby releasing the former and latching the latter, the arrangement being such that one push rod is released and the other is latched by merely pushing the rod selected to be latched.

4. An automatic service-reserve changeover mechanism comprising a pair of gas supply regulators each'including a gas inletnozzle, a valve lever, a valve seat on said lever facing said nozzle,a valve lever,"a valveseat on said leverfacing said nozzle and providing a gas supply valve,

' .5 a gas pressure responsive diaphragm connected to said valve lever, means including said diaphragm providing a gas pressure'chamber for each" regulatonsu'ch chambers having a common gas outlet, a compression spring acting on the ,iside of" said diaphragm opposite each chamber towclosesaid valve, and a push' rod compressing said spring, andcommo'n latch means acting by virtue of'the 'force'of one of said springs automatically torelease" one push rod and latch the other push rod when the latter is pushed' to load its spring.

'5.- An automatic service-reserve changeover mechanism comprising one body having two gas inlet-passages, two gas chambers, and a coing mon gas outlet, a diaphragm member disposed on said body, a second bodyhaving two spring chambers and a common way, said second body being disposed on said'diaphragm member with.

said spring chambers opposite said gas chambers, means securing said bodies together with the diaphragm member clamped therebetween, compression springs in said spring chambers acting against the resulting diaphragms, valves in said gas chambers operatively connected to said diaphragms, push rods compressing said springs, said rods each having an exposed push-end and a lateral recess, and a reciprocatory cross bar in said common way, one end of said cross bar engaging a recess and thereby latching one of said push rods in spring loaded position by virtue of the contact of the other end of said bar with the periphery of the other rod.

6. In a service-reserve changeover mechanism, a gas supply regulator comprising a regulator spring, a spring push rod which is tubular, a push-button removably mounted on the outside of said rod, retaining means mounted on the inside of said rod, a screw threaded in said retaining means, said screw being accessible through said tubular rod when the push-button is removed, and a spring engaging member disposed between said spring and said screw, so that the force of said spring may be adjusted by adjusting said screw in said retaining means.

7. In a service-reserve changeover mechanism, a gas supply regulator comprising a body having a spring chamber, said body having a hole in line with said chamber, a hollow push rod in said hole, said rod having a shoulder, an adjustable annular stop for said shoulder, threaded to said body within said hole for limiting the outward movement of said rod under the force of said spring, and a push-button having a stem secured within said hollow push rod, said pushbutton being adapted to engage said body for limiting the inward movement of said rod.

8. In a fluid pressure regulator, in combination, a casing having a chamber provided with a fluid inlet; means, including a diaphragm responsive to the fluid pressure within said chamber, for controlling the admission of fluid through said inlet; and adjustable means for applying force against the outer side of said diaphragm, said adjustable means including a spring bearing against said diaphragm, an adjustable abutment mounted on said casing and having a bore extending therethrough, a push rod in said bore, said push rod having a shoulder adapted to engage said abutment, said push rod also having an axial bore, a screw bearing against said spring and adjustably mounted in one end of said bore;

and a; push button: closing theopposite. end. of: said bore..

9; In an automatic-changeover mechanism,-.the: sub-combination comprising a: body having spaced parallel push-rod bores, and a common. cross-- bar way extending between suclr bores; 9;; push;

rod disposed in each, bore for limited: longitudiz nalmovement between in and out. positions;. and a cross-bar disposed in. such. way for limited' longitudinal. movement between; said rods,. the ends of said' bar and the lateral surfaces-of said rodshaving cooperating shapes adapted tol cause the bar to positively locklone pushsrod; in: in position when the other-push rod: is in out position, and: permit the latter. push rod" to. be" moved to in position to alternate thelock; said.

cross-bar being completely housed within the body.

10; In-a service-reserve changeovermechanisrrr; a fluid" pressure regulator comprising a regulator spring, a push-rod, a body having a chamiher for said spring, a stop for: said push-rode ad'- justably mounted on saidbody, adjustable: meansincluding axscrew disposed between-saidpushsrodi and, said spring, and means for-latching said rod to, hold the rod in place after. said spring has:

been compressed, the'adjustment of said-stop-and I screw determining the minimum spring-compres- REFERENCES CITED The following references are of record in the.

file of this patent:

UNITED STATES PATENTS Number Name Date 986,921 Jackson Man. 14, 1911. 2,168,701 Buttner Aug. 8, 1939,v