US2602468A - Flow restrictor - Google Patents

Description

y 8, 1952 G. w. ALLEN HAL 2,602,468

FLOW RESTRICTOR 2 SlEETS-Si-IEET 1 Filed May 4, 1946 I I I .3 WW do .31 15 M 9 G. w. ALLEN ETAL 2,602,468

FLOW RESTRICTOR Filed May 4, 1946 2 SHEETS-SHEET 2 Patented July 8, 1952 rUNlTED STATES PATIENT 2,602,463 v FLOW RESTRICTOR.

George W.-Allen and Vernon N. Tramontini, In-

dianapolis, Ind assignors to Stewart-Warner Corporation, Chicago, 111., a corporation of Virginia Application May 4, 1946 Serial No. 667,395 30mm. (01. 138-42) is to provide-a novel control valve having aplurality of valve elements therein, operable iii-re sponse to temperature conditions in the heating tion comprises a main casting l forming a valve body which mounts or houses-an automatic pressure regulator 12, an on-off solenoid operated valve l4, a second on-off solenoid valve l6, and a flow-restricting means l8. The valve body Iii should be aluminum or some other nonmagnetic metal and is formed with an inlet 20 and an outlet 22, both of which may be provided with standard pipe threads for connection 'into the fuel supply system of an internal combustion heater. The on-off valves l4 and I6 and I the flow-restricting, pressure reducing means I8 system including an internal combustion type heater to obtain high heat, 1ow heat, and no heat output.

Another object is to provide a novel unitary control valve which will supply fuel to an internal-combustion heater at a rate designed to give the desired optimum heat'output from the heater, in responseto conditions existing in the heater and heating system.

' Another object is to'providea novel control valve in a single-unit which will supply liquid fuel to a heater of the internal combustion type at a predetermined pressure regardless of the pressure at the inlet to the control valve.

Another object is to provide a new and improved control valve which incorporates one or more electromagnetical'ly operated valve members. 7 r r A further object is to provide'a novel control valve incorporating a unique means'for reducing pressure and restricting fuelflow WithOUt'StOP-r ping the flow completely.

Still another object is toprovide a new and improved'control valve having the aforementioned advantages and which is comparatively simple in construction, rugged,and easily adjusted;

7 Other objects and advantages will become apparent from the followingdescription taken in conjunction with'the accompanying drawings in which:'-

Fig. lis-a top plan viewof the novel control valve forming the subject matter of the present invention;

Fig. 2 is an end elevational view of the control valve;

Fig. '3 is asectional View on an enlarged scale taken substantially along the lines 3-3 of Fig. 1- but showingsome-of the elements in elevation;

4'is across sectional view taken substantially along the lines 44- of Fig.3 and Fig. 5 is a cross'sectionalview taken substantially along the lines 5-5 of Fig. 4.

The novel control valve of the present invenare positioned in the passageway, hereinafter described, connecting the inlet 20 and the outlet 22. The inlet 26 is adapted to be connected to a fuel pump or other suitable source for supplying fuel under pressure, while the outlet 22 may be connected directly to the inlet to an internal combustion heater. tThe inlet 20 isconnected to passageway 24 formed in approximately the center of the valve body Ill, passageway 24 leading to a cross passageway 28 at right angles thereto. Passageway 26 is connected to an enlarged cylindrical threaded bore 28 into which the automatic pressure'regulator l2 of well known construction is threaded. Leakage past the pressure regulator l2'is prevented by a sealing gasket 30 which-is heldaga inst a shoulder 32' at the upper end of the bore 28 by the upper end of the pressure regulator t2; The outlet of the pressure regulator l2 opens into an enlarged cylindrical chamber 34 formed in a depending portion 3 6 of the valve body. The chamber 34 is closed by a flexible diaphragm'38 which is held at its outer edge between a circumferential flange 49 formed on a domelike'housing 42 and the depending portion 36.

'The flang'e 40 and diaphragm 38 are secured'to thefcasting Ill by suitable machine screws 44, and the diaphragm 38 thus forms a fluid and pressure tight seal for the' chamber 34 against theatmosphere f g I At its center, the diaphragm 38 is retained between a largecup-like washer 46 and the head of a rivet 48.-. The washer 46 has a roundedperipheral edge lying against the diaphragm 38 to prevent cutting. the diaphragm .when itis flexed upwardly, as seen inFig. 3. The diaphragm 38 is urged upwardly against the pressure in the chamber 3&- by a spring 50 which is held between a pair of cups 52 and 54, the cup 52 being a part of the washer and the rivet structure-and the cup 54 being fixedly mounted on the end ofan r es 3 adjustment screw 56 which is threaded into the dome of the housing 42.

The head of the rivet 48 bears against the lower end of a valve stem 58 of the automatic pressure regulator I2; when the pressure in the chamber 34 drops below a predetermined desired value, the spring 50 flexes the center of the diaphragm and moves the valve stem 58 upwardly thereby further openin the valve in the automatic pressure regulator I2 to increase the fuel fiow and the pressure in the chamber 34.

A passageway 68 lead away from the cham ber 34 toward the solenoid controlled valve I4, which controls the flow of liquid fuel through valve port 62. The valve port 62 and thepassageway 60 communicate with a valve chamber 64 in which reciprocates a valve body 66 formed as a movable iron core armature of the solenoid.

The solenoid comprises winding 88 having a conductor I and aground terminal I2, the movable armature 66, and a fixed iron core I4. The solenoid winding is wound around an insulating sleeve I6. The sleeve 76 has a friction-fit engagement witha second sleeve I8 formed of a non-magnetic metal such as brass which is tapered at 80 to insure proper centering relative to the iron core I4 and so that the sleeve I6 is easily started during assembly. The solenoid winding 68 is covered with a wrapping 82 of an impregnated insulating material and is covered by a second sheet of a similar material 84, which is wrapped around the conductor I0 to insulate it from contact with the metal parts of the control valve. 7 The sleeve [8 is rolled back at 86 and is provided with a flange 88 which is positioned in a recess 80 in the casting I0 and which with a gasket 02 forms a pressure and fluid tight seal for the valve chamber 64 against the atmosphere. The fiange 88 and the gasket 92 are retained in the recess 90 by thebottom wall of a housing .94 made of iron or some similar magnetic flux conducting material. The housing 94 is secured to the casting valve body ID by suitable bolts 96 and has an opening 98 to accommodate the sleeve .78. At its opposite end, the sleeve 18 is rolled inwardly at I00 against the outer end of the fixed iron core I4 so that the core fixe the end of the sleeve, as will appear presently. As the inside of the sleeve I8 is open to the valve chamber 64, it is insulated-against pressure and fluid leakage by a gasket I02 secured in a circumferential groove I03 in the iron core I4. The solenoid winding 68 is positioned in the housing 94 and is .connectedat one end to a terminal washer I04 secured between the end of the sleeve 18 and a housing cover I06 by means of a machine screw I08 threaded into the iron core 14. The circuit through the solenoid winding may be traced through the conductor I0, solenoid winding 68, terminal lead I2, washer I04, and to ground. The cover I06 for the housing is provided with an opening III] for the conductor 10 inwhibh is secured a synthetic rubber grommet I12;

4 H8 is rolled into a groove I24 in the arma ture 66.

When'in closed position, the synthetic rubber pad I I6 seats against a circumferential valve face I26 surrounding the port 62 and seals the port 62 against communication with the chamber 64. When the solenoid is energized by its controlling circuit, a magnetic field is setup which bridges the air gap between the movable armature 66 and the iron core I4 thereby moving the armature 66 to the right to open the port 62 to establish communication between the chamber 64. passageway 6fl,and chamber 34 on the one hand and passageway I36 leading from .port 62 on the other hand. The magnetic circuit is set up through the housing 94, housing cover I06, iron core "I4, and movable armature 66, and the field so 'set up closes the air gap existing between the core I4 and. the armature 66 to open the on-ofi valve I4. Thus the magnetic field has a substantially closed path through materials of high permeability. It is to be noted that the armature 66 slides freely in the sleeve I8, and that this sleeve is ordinarily filled with liquid fuel since it is in constant communication with the chamber 64, but leakage of the fuel from the sleeve I8 is prevented by the gasket I82.

Solenoid valve I6 has a construction identica with that of solenoid valve I4 and, consequently, need not be described in detail. It includes a movable armature I28 which reciprocates in a chamber I30- The chamber I30 i connected to the port 62 through passageways I32, I34, and

I36, which are drilled or cored in the casting I0 (Fig. 3) and communicates with the outlet 22 through passageways I38 and I40 (Fig. 5).

When the solenoid valve I6 is closed and the solenoid valve I4 is open, fuel is fed to the outlet 22 through the flow of restricting means I8 which has its inlet connected to thepassageway I34 and which is connected to the passageway I40 through a cross passageway I42. The fiow restricting means I8 is formed generally by placing a plurality of very tiny orifices in series in a passageway which connects the passageway I34 with the passageway I42. The orifices are formed in a thin sheet metal plate I44 which is retained between a pair of gaskets I46 and I48. The gasket I46 is placed against a smooth, machined surface I 50 on the valve body I0 and the upper surface of gasket I48 is engaged by the under surface of a circular retaining plate I52. The assembly of the orificed plate I44, gaskets I46 and I48, and plate I52 is mounted in sandwich form on the valve body I I) by machine screws I54. The arrangementof the orifices in the plate I44 is most clearly shownin Fig. 4. The'fuel flows through the orifices in the following order: I56, 158, I60, I62, I64. I66, m, and no. Orifice I56 is in communication with passageway I34 through a circular opening H2 in the gasket l 46 (Fig. 3). Orifice I56 is in communicationrwith orifice I58 through a slot I14 formed in gasket I48. In turn, orifice 1 I58 communicates with orifice I68 through a similar opening I-I6 formed in gasket I46. A similarly shaped opening-I18 is formed in gasket I48 to connect the orifice ;I60 with orifice I 62 which, in turn, communicates with orifice I64 by means of a slot 'I18-formed in gasket I46. Slot I80, formed in gasket I48, connects orifice I64 with orifice I66, which is placed in communication with orifice I68 through an opening'I82 in gasket I46, and orifice I68 communicates with outlet orifice I I0 through an opening I84 formedin the gasket I48. The slots which have been described as1 .b eing.formed in thegaskets I46 and I43 formthesepassageways connecting adjacent orifices in the plate. I44.- by being confined between the casting III. and :the orificed plate I44, and between plate I44 andthe retaining plate I 52, respectively. I This COnStruC? tion, is clearly shown in Figs. 3- and 5.. Whenv the shut-off valve I4'is open and the valve I 6 is closed, thefuel; will be meteredthrough these minute orifices which are arranged in series between; the gri andindividuallymounted on thecasting Iii-on an outwardly facing surface: 1 I In assemblingthe control valve,- the automatic pressureregulatorfl is screwed into the threaded opening-28 afterthe gasket 30 has been placed against the. shoulder 3-2. placed over the vend of -the automatic pressure regulator so that the rivet48 engages the valve stem 58. The coil springfic isconfinedbetween the cups 52 and 54 asthe dome-like housing 42 is mounted on the casting Iilby the machine screws- 44. If, for example, it is desired that the pressure of the fuel in the chamber =34 be 1 p. s. i. gauge, the action of the diaphragm'ds adjusted to drop the pressure at the inlet 28 which'maybe 3-or. d pusi ifgauge, to 1 p. s. i. in the chamber 34. In order accurately to obtain this regulation, the compression on the spring 50is-carefully adjusted by'means ofithe screw 56. When this adjustment has been made, the screw maybe secured in position by placing a ring of solder I86 around the screw 56 where it contacts the dome-like housing 42.

The flow restricting means I8 may then be mountedon the casting I0. Gasket I46 isplaced against the machined surface I50 on the casting I0; Orificed plate I44 and-gasket I48 are, in turn, laid-on'the top of gasketllltf, and then the retaining'plate' I52 is putin position, the whole being secured to the casting I0by means of the machine screws I54. The-gaskets are compressed slightly so as to provide a' pressure and fluid tight seal in the passageways'formed by the retaining plate I52, gaskets I46 and I48, plate I44, and casting I0. Care must be taken to insure the proper sequential relationship betweenv the orifices formed in the plate I44 and the slots formed'in each of the gaskets I46 and I48. In order that this might be facilitated, the mounting holes in the plate I44, gaskets I46 and I48, plate I52 and casting ID are offset relative to a symmetrical or equi-angular spacing so that they may assume only one position relative to each other with the mounting holes coinciding.

The solenoid control valves I4 and I6 may then be readily assembled on the casting I0. The sub-assembly of the sleeve 18, iron core I4, and armature 66 is assembled before mounting'the casting I0. This sub-assembly is mounted with The diaphragm 38 is accents respective holes to secure the sleeve and movable elements of the valve to the casting I10. The solenoid winding 68, which has previously been wound on the sleeve I6, may then he slid onto. the sleeve 18 with which the sleeveIG is in friction engagement. The solenoid winding carries the washer I04 which is held securely against the housing cover I06 by the screw I08. .Theother solenoid controlled valve I6 .is assembled in a similar manner.

The control valve forming the subject matter of this invention is particularly well adapted for supplying liquid fuel to an internal combustion heater at the rate required to maintain'the'output of the heater suflicient to maintain the temperature of the space being heated at a desired and controllable level. For example, in starting the heater, it might be required that it deliver a maximum output of 20,000 E. t. u. per hour. The control valve, which has been described, and with the pressure examples which have been given in the description, which are at between 3 and 4 p. s. i. gauge pressure at the inlet 20 'and .l' p. s. i. gauge pressure in the chamber 34, will be in fully open position. In thisv positiomthe solenoid controlled valves I4 and I6 are both open, that is, the solenoids are energized-so as to move the valve armatures 66 and I28 tothe right and to the left, respectively (Fig. 3) When the space to be heated has warmed to a predetermined temperature, and it is desired merely-to maintain that temperature, the solenoid con-a trolled valve IE will be tie-energized and the spring biased armature valve body I28 willmove to the right, shutting off the flow of fuel between the valve chamber I30 and thepassageway I38;

the flange 88 in the recess 90 in such position as to hold the gasket 92 against its seat and to position the rolled edge 86 slightly within the valve chamber 64. The housing 94 is then slipped over the sleeve I8 and against the flange 88 to hold the sleeve I3 and associated parts in place, and the machine screws 96 are threadedinto their This shuts off the flow of fuel from the chamber 64 through the chamber I30 to the outlet 22 'via the passageways I34, I32, and I38. I However, the chamber 64 is in communication with the passageway I34 through the open port 62, and the passageway I34-is in communication with the outlet 22 and passageway I42 leading thereto through the flow restricting means It which comprises the tortuous passageway formed by the'casting It, gasket I40, plate I44, gasket I48, and retaining plate I52. This tortuous passageway is provided with the plurality of interconnected orifices I56, I58, I85, I62, I54, I58, and 510, which reduce the flow rate so that the heater output will be approximately 5,000 B. t. unper hour. If the temperature of the space to be heated then drops below a satisfactory level, the valve I6 is reopened to establish high heat operation.

If the-temperature in the space to be still rises above the desired maximum, or if the heater tends to overheat, even though valve It is closed, it may be desirable to interrupt heater operation, in which case the solenoid, valve I4 closes through the deenergization of its circuit.

When the fuel feeding system to the heater is in operation, the chamber 34, the valve chambers 64 and I30, and all of the passageways in the valve body III will be completely filled with fuel. Thus there will be no air pockets present and the flow of fuel from the outlet 22 will be instantaneous upon opening the valve, and at a rate determined by the positions of the solenoid valves I4 and I6.

The examples for thermal output of the heating system and the fuel pressures which have been given in the foregoing description of this invention are merely illustrative, and it is to be understood that they may vary according to the heated 7 particular installation. Should the required pressure drop between the chamber 34 and the outlet 22through the restricting means 18 be greater than that which can be-obtained with the number of orificesillustrated herein, more orifices may be used in the series. Conversely, fewer. or larger orifices may be used when less restricting effect is desired.

While. there has been described but a single embodiment of the invention, it is appreciated that changes and modifications maybe made therein without departing from the sphere and scope of the-invention, therefore, what is desired to be claimed as new and secured by United States Letters Patent is:

1. A liquid flow restrictor comprising a thin plate having a plurality of tiny orifices formed therethrough from face to face, said orifices being of such size andnumber that the pressure drop through a series connection of said orifices produces the desired restricting effect, and passage forming means having substantially no restricting, effect disposed on both sides of said plate for connecting said orifices in series so as tocause liquid to fiow alternately from one side of saidplate to the other by way of said orifices.

2. A liquid flow restrictor comprising a body portion having a fiatface, said body portion being formed to provide liquid inlet and outlet connections and passages leading from said connections respectively to liquid inlet and outlet ports formed in said fiat face, a cover having a flat surface adapted to cover said ports, means forsecuring said cover to said body portion, a

- thin flat plate disposed between said body portion and said cover, said plate having a plurality of small orifices'formed therethrough from face to face, a body gasket disposed between said body and said plate, a cover gasket, disposed between said cover and said plate, said body gasket having aplurality of apertures formed therein which form individual spaces when said body gasket is confined between said body and said plate, one of said spacesintersecting said inlet port and another of said spaces intersecting said outlet port, said cover gasket having a plurality of apertures formed therein which form individual spaces when said cover gasket is confined between said cover and said plate with the apertures in said cover gasket disposed so as to intersect and interconnect the apertures in said body gasket, the orifices in said plate being located with one at each of said intersections so that the liquid is required to flow back and forth between the two faces of said plate by way of said orifices as the liquid passes from said inlet port to said outlet port, and said orifices being "8 so small as comparedwith said spaces that substantially all of the restricting effect on said liquid is due to the series arrangement of said small orifices.

3. A liquid flow restrictor comprising a pair of members having fiat faces, a thin plate clamped between said faces, said plate having a plurality of small orifices therethrough from face to face, a pair of gaskets disposed with one between said plate and one of said members and the other between said plate and the other of said members, one of said gaskets having a plurality of apertures therein with each of said apertures overlapping separate pairs of said orifices so that said orifices are connected into individual sets of two each'by the passages formed by said apertures when said one gasket is confined between said plate and its member, the other of said gaskets having a plurality of apertures therein with each of the last said apertures overlapping other separate pairs of said orifices so thatsaid orifices are connected into individual sets of two each by the passages formed by the apertures in said other gasket when said other gasket is confined between said plate and its member such that said orifices are connected in series by the passagesformed on alternate sides of said plate, means for establishing liquid inlet and outlet connections at opposite ends of said series, and said orifices being so small as compared with said passages that substantially all of the restricting effect on said liquid is due to said orifices in series.

GEORGE W. ALLEN. VERNON N. TRAMONTINI.

REFERENCES CITED UNITED STATES PATENTS Number Name Date 353,227 Kuyl Nov. 23, 1886 874,517 Lowry Dec. 24, 1907 1,057,943 Dalen Apr. 1, 1913 1,652,171 Hufi' Dec. 13, 1927 1,964,300 Perry et a1 June, 26, 1934 1,983,227 Hall et a1. Dec. 4, 1934 2,118,290 Black May 24, 1938 2,118,295 Crawford May 24, 1938 2,210,448 Dodge Aug. 6, 1940 2,236,084 Brown Mar. 25, 1941 2,310,745 Parks 1 Feb. 9, 1943 2,343,806 Scofield Mar. 7, 1944 FOREIGN PATENTS Number Country Date France Apr. 3, 1912

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