US2894829A

US2894829A - Gas regulators for gas engines

Info

Publication number: US2894829A
Application number: US396022A
Authority: US
Inventors: John W Harrison; John R L Middleton
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-12-03
Filing date: 1953-12-03
Publication date: 1959-07-14
Anticipated expiration: 1976-07-14

Description

u y 1959 J. w. HARRISON ETAL 2,894,829

1 GAS REGULATORS FOR GAS mamas Filed Dec. 3, 1953 A rrl l m F/ J] 7 30b 9 42 v 40 Z i v v /6 dohn VV. Harr/Jjon 1/0/20 R L. M/a d/ezon l8 3/ Y INVENTORS J3 Maul;

A fro/awe Y6 Unite GAS REGULATORS FOR GAS ENGINES John W. Harrison and John R. L. Middleton, Corsicana, Tex.

This invention relates generally to new and useful improvements in gas regulators for gas engines and relates particularly to a starting and idling device to be used therewith.

The invention is primarily adapted for use in controlling the fuel supply under starting and idling conditions to internal combustion engines which operate on natural gas, or the fuel ordinarily referred to as LPG, liquefied petroleum gas, such fuel consisting of butane or propane or a mixture of these and similar hydrocarbons.

Where gaseous fuels are employed for operating an internal combustion engine, the accurate control of fuel supply to the engine under idling and starting conditions has presented a considerable problem. This is due primarily to the fact that the depression created by the air flow across the venturi in the carburetor being communicated to the low pressure side of the regulator causes it to open and feed in gas. Thus the regulator must be of suflicient size to supply the large volumes required under full load. As a result, the device cannot give accurate control of the amount of gas fed at starting and idling speeds since at that time there is only an infinitesimal depression created at the venturi because there is practically no air flow. To remedy that condition, various steps have been taken, none of them effective. On the vacuum type regulators, pilot or accessory diaphragms and valves (other than the main diaphragm and valves) are acted upon by the vacuum from the intake manifold to actuate in turn the main valve of the regulator to supply the very small requirement for low speed operation. On this type, the amount of the vacuum acting on the pilot diaphragm determines its actuating force, With the result that any slight change in vacuum caused by leaky valves, throttle not returning to same closing point, etc., will produce a variation in the amount of gas fed with consequent poor operation; also, in this type of system, the amount of the gase for low speed operation is determined by controlling the amount of vacuum acting on the pilot diaphragm and is, therefore, dependent on the amount or degree of vacuum.

' One object of the invention is to provide an improved device for controlling the flow of gas to an internal combustion engine in which the usual pressure responsive member for controlling flow of main supply gas to the carburetor is closed ofi tight while the engine is not running and in which the means for furnishing idling gas to the carburetor induces a predetermined vacuum on the pressure responsive member so that it is sensitive to small changes in vacuum above idling conditions.

An important object of the invention is to provide an improved device for controlling the flow of gas to an internal combustion engine in which the usual pressure responsive member for controlling flow of main supply gas to the carburetor is closed off tight when the engine is not running and in which means apart from the manifold vacuum automatically induces substantial balance across the pressure responsivemember while the engine is idling so that the pressure responsive member will re spond to slight changes of vacuum in the manifold above idling conditions and the venturi restriction in the carburetor throat may be relatively large or wide open.

rates Patent lCe A further object is to provide an improved device of the character described which is applicable to any standard controlling device such as the usual two-stage regulator and which may be so combined with such regulator that the source of the idling gas may be withdrawn from the first stage of said regulator.

Still another object is to provide an extremely simple device which may have a separate control for initially opening the valve to the idling gas chamber, whereby the vacuum developed by the engine in starting need not be depended upon to initiate operation of the device; said separate control being actuated either manually or by some automatic means.

The construction designed to carry out the invention will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specifications and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

Figure 1 is a schematic view of a starting and idling device constructed in accordance with the present invention and showing the same combined with a standard two-stage regulator and connected with the intake of an internal combustion engine; and

Figure 2 is a transverse Vertical sectional view of the starting and idling device comprising the present invention.

In the drawings the letter A designates the improved starting and idling device constructed in accordance with the present invention which is illustrated as combined with the usual or ordinary two-stage regulator B. The letter C designates a typical carburetor of an internal combustion engine, and as illustrated in Figure 1 the carburetor includes an air intake 10, a venturi passage 11 and a throttle valve 12. The carburetor has. connection with the usual intake manifold 13. Gas is supplied to the venturi passage 11 of the carburetor through a gas supply line 14 which extends from the outlet side of the regulator B. Gas is supplied to the regulator through inlet 15.

As will be explained hereinafter, the device A is provided for the purpose of supplying gas for starting and idling to the engine and a conductor 16a extends. from the device A to the supply line 14. The device A is actuated by the vacuum developed by the engine and a connecting line 17 connects said device with the intake manifold. When the engine is first started and during the idling period prior to opening of the throttling valve 12, the vacuum acting through line 17 operates device A so that gas is supplied through conductor 16a and then through conductor 14 to the carburetor.

The regulator B forms no particular part of the present invention and may be of any desired construction. As illustrated, it includes a chamber 18 which has communica tion with the inlet conductor 15 through a valved opening 19. A valve 20 which is actuated by a diaphragm 21 controls the admission of gas into the first stage chamber 18. From the first stage chamber the main volume of gas for operation of the engine is adapted to flow through opening 22 which is controlled by a valve 23. The valve 23 is actuated by a diaphragm 24 in the second stage chamber 25 of the regulator. Diaphragm 24 is responsive to the depression created by the air flow through venturi 11, and thus the gas from the second stage is furnished the engine during operation thereof. An equalizing line or balance line 26 which extends from the area below the diaphragm 24 to a point adjacent the air intake 10 of the carburetor effects an equalization of pressure between these points. In the event of an unbalanced condition due to partially plugged air cleaner, pressure build-up due to blast of air from fan, etc. The regulator above described and schematically illustrated is of ass gsae standard construction, and any suitable regulator for supplying gas to the engine during operation thereof may be employed.

The regulator B is of a size to provide the required volumes of gas under operating loads, and it is diflicult to make the relatively large diaphragm 24 extremely sensitive to such slight depressions as are encountered at the starting and idling periods. Thus, the regulator B is satisfactory in its operation when the throttle valve is open and the engine is in normal operation; however, the control elements of the regulator are not sensitive enough at starting and idling to accurately control gas volumes flowing to the carburetor.

In carrying out the present invention the device A is employed in combination with the regulator B and provision is made to obtain the gas supply which passes through device A from the first stage chamber 18 of the regulator. It is pointed out, however, that although this is a convenient source of gas supply, the invention is not to be limited to connecting the device A with the first stage chamber since the gas flowing through device A, as will be hereinafter explained, can be obtained from any suitable source.

Referring to Figure 2, the device A comprises a housing 39 which is preferably made up of

annular sections

30a, 30b and 30c, which are secured together by flanged or other connections. The lowermost or base section 30a may be bolted to the upper end of the regulator B and an opening 31 is provided to establish communication between the first stage chamber 18 of the regulator and the lower end of the interior of the housing 30. A valve seat member 32 may be threaded in said opening and a valve 33 is adapted to engage this seat. The valve 33 is provided with a stem 34 having its upper end connected to a diaphragm 35, said diaphragm having its marginal edge portion secured to an annular ring or partition mem ber 36' which is disposed transversely within the housing. It will be evident that the area below the diaphragm 35 forms a chamber 37, and when the diaphragm 35 is moved downwardly to unseat the valve 33, gas from the first stage chamber 18 may flow into chamber 37. The conductor 16a which has connection with the supply conductor 14 leading to the carburetor has one end in communication with the chamber 37 so that the gas from chamber 37 may flow through conductor 16a and into the supply conductor 14 from where it may enter the venturi of the carburetor. For controlling the volume of gas flowing through conductor 1611 a manually adjustable valve 38 is provided, and thus the gas passing from chamber 37 to the supply conductor 14 is controlled.

Above the diaphragm 35 the interior of the device has a transverse partition member 33 which is provided with a central opening 4! An actuator plunger 41 has its lower end engaging the upper surface of diaphragm 35 with its upper end slidable within a flanged follower sleeve 42, said sleeve being slidable within the opening 40. A coil spring 43 within the upper end of the sleeve bore engages the upper end of the plunger to maintain the plunger in contact with the diaphragm 35.

Disposed in the upper portion of the device A above the follower sleeve 42 is a large operating diaphragm 44 which spans the interior of the upper section 30c of the housing. The area 45 below the operating diaphragm provides a chamber which is in communication through the line 17 with the intake manifold. It is obvious that the vacuum developed in the intake manifold acts through the line 17 and upon the under side of diaphragm 44, pulling said diaphragm in a downward direction; since diaphragm: 44 is in engagement with the follower sleeve a downward pressure is applied through the sleeve, coil spring 43 and plunger 41 to the smaller diaphragm 35 which has connection with thevalve 33. The size of the diaphragm and the relationship of the'parts of the device are such that at any time that the engine is. turning. over; that is, either during starting or idling, the vacuum in the 4 intake manifold is sufiicient to move the operating diaphragm 44 in a downward direction sufficient to open the valve 33. Opening of the valve admits pressure from the first stage chamber 18 of the regulator B to the chamber 37, and this pressure acts upon the diaphragm 35. The strength of the spring 43 is so adjusted that a predetermined pressure, for example, in the order of three pounds, is maintained in chamber 37, and at any time that the pressure exceeds this amount the lower diaphragm 35 functions to close the valve 33. It is noted that closing of the valve 33 can be effected with the operating diaphragm 44 in its lowermost position because of the relative movement which is permitted between plunger 41 and sleeve 42 due to the spring connection therebetween.

So long as the engine is developing any vacuum, the operating diaphragm is in its lowermost position and the valve 33 is urged toward open position. The lower or smaller diaphragm 35 functions to maintain a predetermined pressure in the chamber 37 and thus chamber 37 actually serves as a source of gas supply of a constant or fixed pressure. It should be noted here, that whenever the design of the first stage chamber diaphragm 21, valve 20, etc. is such that there is maintained in chamber 18 a constant pressure, a certain portion of device A may be dispensed with. Plunger 41 may be fixed into sleeve 42 togive the first stage pressure in chamber 37 instead of a reduced pressure. The operation of device A remains the same, this merely being a slight variation in the construction as shown in Figure 2.

From the chamber 37 the gas may flow through conductor 16a in accordance with the adjustment of valve 38 and to the supply conductor 14 leading to the carburetor. If any variation occurs in the degree of vacuum in intake manifold 13, this will not affect the supply of idling gas because any vacuum in intake manifold, acting through line 17, will maintain the operating diaphragm in its lowermost position. It is noted that there is no flow of gas through line 17 which is the vacuum line for permitting the vacuum to act upon diaphragm 44, but instead the idling gas is directed through conductor 16a from the chamber 37 which, as has been noted, is a source of gas of constant pressure.

It may be that upon initial starting the operator may not desire to depend upon the vacuum developed upon turning over of the engine to initially move the operating diaphragm 44 downwardly. In such case a plunger 46 may be mounted in the upper end of the device A with its lower end in engagement with the upper surface of diaphragm 44. Upon initial starting the plunger 46 may be manually depressed to open valve 43 and as soon as the engine starts, the vacuum from intake manifold 13 will maintain the operating diaphragm 44 in its lowered position. If desired, plunger 46 may be mechanically operated or electrically operated by means of an electrical coil or solenoid indicated at 47. Actually, the plunger 46 is not absolutely essential although it does assure that the initial supply of gas will reach the carburetor as the engine is started.

Gas is fed through conductor 16a to a jet 48 placed in supply conductor 14, the jet being directed toward venturi 11. With this arrangement, when gas is fed to the jet, the pressure is reduced behind the jet and in second stage chamber 25 to the point where the valve 23 is just ready to open and supply a large amount of gas in. case the throttle is opened suddenly.

The operation of the device is believed to be evident from the foregoing. When the engine is not operating the movable parts of the device A are in the position shown in Figure 2, and at this time there is a predetermined gas pressure in the first stage chamber 18 of the regulator B, If the startin plunger 46 is used this plunger is depressed at the time the engine is started to effect an initial opening of the valve 33; however, if plunger 46 is not employed, the turning over of the engine in starting develops a vacuum which moves the operating diaphragm 44 downwardly. As explained, this opens the valve 33 to admit gas from the first stage chamber 18 of regulator B into the chamber 37. From chamber 37 the gas flows through conductor 16:: and to supply conductor 14 to the carburetor. The valve 38 is manually adjusted to control the flow and thereby assure that the proper volume of gas will pass to the carburetor for efiicient idling. Gas continues to enter the chamber 37 and will, of course, enter the same faster than it escapes through conductor 16a and the pressure in chamber 37 is thereafter regulated by the diaphragm 35. Thus, during all ranges of idling a fixed constant volume of gas is conducted to the carburetor. Any variation in the degree of vacuum in intake manifold 13 will not change the volume of gas flowing to the carburetor during idling because all that the vacuum in intake manifold 13 accomplishes is to hold the operating diaphragm 44 in a lowered position. Such downward position of the diaphragm 44 will be maintained so long as there is any vacuum in the intake manifold, and thus so long as the engine is operated, operating diaphragm 44 remains in a lowered position. There is no flow of gas through the vacuum line 17, and for this reason, changes in degree of vacuum will not alfect volume of gas flowing to the carburetor. The chamber 37 provides a source of gas supply of constant pressure and thus the volume of gas flowing to the engine under starting and idling conditions is controlled solely by adjustment of the valve 38. By proper adjustment of this valve, efiicient idling and starting operation can be eflfected.

When the throttle valve 12 is opened to operate the engine under load, the regulator B comes into operation in the usual manner to provide the gas necessary for such operation. During this time gas may also be flowing through device A and conductor 16a, but the amount of this gas compared to the gas required for engine operation under load is so small as to be negligible in effect so far as operation is concerned. At any time that the throttle valve is closed to return the engine to an idling speed, the constant supply of idling gas is available through conductor 16a.

The device is relatively simple in its construction and positive in its operation. If the engine is operating at all, valve 33 is open and the proper volume of gas is flowing to the carburetor. Any variation in degree of vacuum throughout the idling period has no effect on the volume of gas being supplied to the carburetor, and thus the disadvantages of attempting to control idling gas requirements in accordance with degree of vacuum are eliminated. As has been noted, the supply of gas to device A is illustrated as being obtained from the first stage chamber 18 of regulator B, but, of course, such gas supply may be from any available source. Also, it is again noted that although a two-stage regulator B is illustrated, the device A may be combined with other types and kinds of controlling devices which are now available on the open market.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

Having described the invention, we claim:

1. In combination with regulating apparatus for gas engines which includes a pressure chamber, a gas inlet conduit connected to the chamber, a gas conductor be tween the chamber and the engine carburetor, and pressure-responsive means in said chamber operated by engine vacuum for controlling the gas supply to the carburetor; a flow control device for controlling the supply of gas to the engine during the starting and idling periods comprising; a housing having a chamber therein; said housing having a gas inlet; a movable valve associated with the inlet for opening and closing said inlet; a gas supply conductor extending from the control device chamber to the carburetor supply conductor, said gas supply conductor having its outlet terminating in a jet nozzle in the carburetor supply conductor and pointed toward the outlet of the carburetor supply conductor; whereby a jet effect is created and draws additional gas fromthe regulating apparatus gas chamber; and means operable by the vacuum in the intake manifold of the engine for controlling operation of the valve to open said valve when the engine is operating and to close the valve when the engine is not operating.

2. The combination with a two-stage regulating apparatus for gas engines which includes, a first pressure chamber and a second pressure chamber, a gas inlet conduit, a conductor between the gas outlet of the apparatus and the engine carburetor, and pressure-responsive means in the chamber operated by engine vacuum for controlling the gas supply to the carburetor; a flow control device for controlling the supply of gas to the engine during the starting and idling periods; said flow control device comprising a housing having a chamber therein; said housing chamber having an inlet in communication with the first stage chamber of the regulating apparatus; whereby gas is supplied to the controlling device chamber from said first stage chamber; a movable valve associated with the inlet for opening and closing said inlet; a conductor extending from the control device chamber to the supply conductor which connects the regulator apparatus with the carburetor, said gas supply conductor having its outlet terminating in a jet nozzle in the carburetor supply conductor for creating a jet efiect in the conductor; and means which is out of communication with the conductor and operable by the vacuum in the intake manifold of the engine for controlling operation of the valve to open said valve when the engine is operating and to close the valve when the engine is not operating.

3. The combination with a two-stage regulating apparatus for gas engines which includes, a first pressure chamber and a second pressure chamber, a gas inlet conduit, a conductor between the gas outlet of the apparatus and the engine carburetor, and pressure responsive means in the chamber operated by engine vacuum for controlling the gas supply to the carburetor; a flow control device for controlling the supply of gas to the engine during the starting and idling periods; said flow control device comprising a housing having a chamber therein; said housing chamber having an inlet in communication with the first stage chamber of the regulating apparatus; whereby gas is supplied to the controlling device chamber from said first stage chamber; a movable valve associated with the inlet for opening and closing said inlet; a conductor extending from the control device chamber to the supply conductor which connects the regulator apparatus with the carburetor and terminates in a jet nozzle in the conductor and for creating a jet effect in the conductor; the jet effect of gas flowing through said nozzle providing a predetenmined vacuum in said chamber, and means controlling flow of gas through the jet nozzle.

References Cited in the file of this patent UNITED STATES PATENTS 1,301,272 Keith Apr. 22, 1919 2,073,298 Ensign Mar. 9, 1937 2,074,268 Lowe Mar. 16, 1937 2,240,846 Hanson May 6, 1941 2,340,954 Garretson Feb. 8, 1944 2,448,131 Williams et al Aug. 31, 1948 2,475,087 Ensign July 5, 1949 2,500,088 Mock Mar. 7, 1950 2,551,758 Newton May 8, 1951 2,597,335 Jones May 20, 1952 2,645,466 Jones July 14, 1953 2,698,226 Peduzzi Dec. 28, 1954

Claims

1. IN COMBINATION WITH REGULATING APPARATUS FOR GAS ENGINES WHICH INCLUDES A PRESSURE CHAMBER, A GAS INLET CODUIT CONNECTED TO THE CHAMBER, A GAS CONDUCTOR BETWEEN THE CHAMBER AND THE ENGINE CARBURETOR, AND PRESSURE-RESPONSIVE MEAND IN SAID CHAMBER OPERATED BY ENGINE VACUUM FOR CONTROLLING THE SUPPLY TO THE CARBURETOR; A FLOW CONTROL DEVICE FOR CONTROLING THE SUPPOLY OF GAS TO THE ENGINE DURING THE STATRING AND IDLING PERIODS COMPRISING; A HOUSING HAIVNG A CHAMBER THEREIN; SAID HOUSING HAIVNG A GAS INLET; A MOVABLE VALVE ASSOCIATED WITH THE INLET FOR OPENING AND CLOSING SAID INLET; A GAS SUPPLY CONDUCTOR EXTENDING FROM THE CONTROL DEVICE CHAMBER TO THE CARBURETOR SUPPOLY CONDUCTOR, SAID GAS SUPPLY CONDUCTOR HAVING ITS OUTLET TERMINATING IN A JET NOZZLE IN THE CARBURETOR SUPPLY CONDUCTOR AND POINTED TOWARD THE OUTLET OF THE CARBURETOR SUPPLY CONDUCTOR; WHEREBY A JET EFFECT IS CREATED AND DRAW ADDITIONAL GAS FROM THE REGULATING APPARATUS GAS CHAMBER; AND MEANS OPERABLE BY THE VACUUM IN THE INAKE MANIFOLD OF THE ENGINE FOR CONTROLLING OPERATION OF THE VALVE TO OPEN SAID VALVE WHEN THE ENGINE IS OPERATING AND TO CLOSE THE VALVE WHEN THE ENGINE IS NOT OPERATING.