US2868224A

US2868224A - Control valves for an appliance burning a gaseous fuel

Info

Publication number: US2868224A
Application number: US560016A
Authority: US
Inventors: Karlsson Helge Johannes; Axelsson Sten Sune
Original assignee: Bahco AB
Current assignee: SNA Europe Industries AB
Priority date: 1955-09-19
Filing date: 1956-01-18
Publication date: 1959-01-13
Anticipated expiration: 1976-01-13

Description

Jan. 13, 1959 H. J. KARLSSON ETAL 2,868,224

' CONTROL VALVES FOR AN-APPLIANCE BURNING A GASEOUS FUEL Filed Jan. 18, 1956 5 Sheets-Sheet 1 Fig; 1

5 Sheets-sheaf a flrrom'vir J 1959 H. J. KARLSSON ETAL CONTROL VALVES FOR AN APPLIANCE BURNING A GASEOUS FUEL Filed Jan. 1a, 1956 1959 H. J. KARLSSON ET AL 2,868224 CONTROL VALVES FOR AN APPLIANCE BURNING A GASEOUS FUEL Filed Jan. 18,1956 5 Sheets-Sheet 6 54 a: Jb/mmws 16m; sac/v Mil my 1959 H. J. KARLSSON" ETAL 2,868,224

CONTROL VALVES FOR AN APPLIANCE BURNING A GASEOUS FUEL Filed Jan. 18, 1956 5 Sheets-Sheet 5 United States CONTROL VALVES FOR AN APPLIANCE BURNING A GASEOUS FUEL Helge Johannes Karlsson, Hagersten, and Sten Sune Axelsson, Hagalund, Sweden, assignors to Aktiebolaget Bahco, Stockholm, Sweden, a corporation of Sweden Application January 18, 1956, Serial No. 560,016 Claims priority, application Sweden September 19, 1955 Claims. (Cl. 137-495) This invention relates to a device for controlling flow of a combustible gas.

Gas appliances often are connected to a source of supply of a combustible fuel which is not always available at a uniform pressure. This is especially true when bottled liquefied petroleum gas is employed as a source of fuel, because the pressure under which the gas is retained in the bottles or cylinders is materially influenced by changes in the ambient temperature of the surroundings.

When a gas appliance is connected to a bottle or cylinder charged with liquefied petroleum gas, and fuel in gaseous phase flows therefrom to the burner of a gas appliance, the pressure at which the combustible gas is delivered to the burner increases and decreases with in crease and decrease, respectively, in the ambient temperature of the surroundings, and the flame produced by the burner will fluctuate in size, which is objectionable.

It is an object of the invention to provide an improved control device whereby gaseous fuel will be supplied to a burner at a uniform rate irrespective of changes in gas delivery pressure.

Another object is to provide an improved device for regulating and controlling the pressure of a gaseous fuel from a source of supply which is subject to variation in gas delivery pressure with change in ambient temperature of the surroundings.

A further object is to provide an improved device for regulating the pressure of a gaseous fuel discharged from a container adapted to hold liquefied petroleum gas, so that the gaseous fuel will be made available at a substantially constant pressure even though discharged from the container at a pressure which varies.

Further objects and advantages of the invention will become apparent from the following description, and the various features of novelty which characterize the invention will be pointed out with particularity in the claims appended to and forming a part of this specificatron.

For a better understanding of the invention, reference may be had to the following description and accompanying drawing, in which:

Fig. 1 is a sectional view of a control device embodying the invention showing the valve member in its closed position;

Fig. 2 is a sectional view similar to Fig. 1 showing the valve member in its fully open position;

Fig. 3 is a sectional view similar to Fig. 1 showing the valve member in a position intermediate its closed and fully open positions; and

Figs. 4 and 5 are sectional views of control devices illustrating modifications of the invention.

Referring to Figs. 1 to 3, the invention is shown applied to a container 1 adapted to be charged with a .liquefied petroleum fuel. The container 1, only a part of which is illustrated, is provided with an opening within which is firmly secured an apertured fitting 2 having a valve 4 therein adapted to be biased against its seat 3 arsenal Patented dart. l3, 1959 by a relatively weak coil spring 5. When a pin 18 connected to valve i is moved downwardly in Fig. 1, in a manner which will be hereinafter explained, the valve is moved from its seated or closed position, thereby allowing petroleum fuel in gaseous form to flow from the interior of the container through a passage 2 of the fitting 2 and past the valve 4 in a path of flow which includes a conduit Ztl to which a suitable gas appliance, not shown, may be connected.

In accordance with the invention, in order to deliver gaseous fuel at a substantially constant pressure to conduit 2d regardless of variations in the pressure at which the fuel is discharged from the container 1, due to changes in ambient temperature of the surroundings, for example, a control device is provided which may be removably secured directly to the container ll. As shown, the control device comprises a hollow body threadedly secured at 6 to the hollow outer part of the fitting 2, the body 7 having a cylindrical chamber 8 within which a plunger 9 is axially movable. The plunger 9 is pro vided with a sealing ring 21 for preventing gas from flowing into the chamber d behind this sealing ring.

The plunger 9 is biased toward the pin lit by a helical spring 10, the tension of which may be adjusted by a cap Lil threadedly connected to the extreme outer end of the body '7. A control knob 12 is secured to the outer end of the plunger 9 for manually turning the latter within the hollow body 7. A pin 13 fixed to the knob 12 cooperates with another pin ltdsecured to a part of the body 7 and forming a bar for the pin 13 so that the knob 11?. and plunger 9, to which it is secured, can only be turned a single revolution. in Figure 1 the knob 12 is turned clockwise as far as possible, and in this position the pin 13 contacts the pin 14, preventing further turning of the knob 12.

The plunger 9 is formed with an elongated hollow sleeve-like section which is internally threaded and receives a threaded plug is, the lower end of which has a transverse passage adapted to hold a guide pin 16. The narrow bottom part of the cylindrical chamber 8 formed in the body 7 constitutes a passage having axially extending guides 17 in which the opposing ends of the pin 16 are adapted to move. In this way, the plug 15 is prevented from turning about its axis, and can only move in a lengthwise direction within the body '7. The extreme lower end 19 of the plug 15 is arranged to act on the pin lit and impart downward movement to valve member l, as will be explained presently.

When the body 7 is threadedly secured. at 6 to the fitting 2, and the control knob 12 is in the valve closing position illustrated in Fig. 1, the lower end 19 of the plug 15 is at the immediate vicinity of the pin 18 but out of engagement therewith, thereby allowing valve 4 to remain in its closed position under the: influence of the spring 5. When the hand knob 12 is turned in a counterclockwise direction in Fig. 1, that is, in a direction which will impart downward movement to the plug 15 within the hollow sleeve-like part of the plunger 9, the end 19 of the plug 315 will engage the pin 18 and impart downward movement thereto to move the valve 4 from its closed or seated position.

When the pressure at which the gaseous fuel is discharged from the container 1, is at or below a predetermined value, the tension of the helical spring ill) will be effective to urge the plunger 9 and thus also the plug 15 downwardly and maintain the valve 4! in an open position, as seen in Pig. 2. Under these conditions, the inner end of the plunger 9 bears against the shoulder 22 of the body "I, and gaseous fuel is supplied to conduit 20 at a rate which is dependent upon the tension to which the spring ill is initially adjusted by the cap 11.

In the event the pressure at which the gaseous fuel is discharged from the container ll exceeds the predetermined value referred to above, the plunger which is subjected to the gas-pressure, will be moved upwardly against the tension of the spring lltl, as shown in Fig. 3. Hence, when the gaseous fuel is discharged from the container l at a pressure which exceeds the predetermined value, upward movement will be imparted to the plunger 9 and plug 15 against the action of the spring 141 and valve 4 will be moved toward its closed position to reduce the size of the valve opening so that the gaseous fuel will be delivered to conduit 24) at a substantially constant pressure.

Another embodiment of the invention is shown in Fig. 4, in which parts similar to those described above and illustrated in Figs. 1, 2 and 3 are designated by the same reference numerals. in Fig. 4- the body 7" is formed with a burner mouth piece 23, and the hand knob 112' and parts of the control device are disposed horizontally and at a right angle with respect to the pin 18 and valve 4.

The plunger 9', spring 10', can 11 and plug illustrated in Fig. 4 are horizontally disposed and laterally offset with respect to the vertical axis of the valve member 4 and pin 18. The hand knob 12 in Fig. 4 is secured to the outer end of the plunger 9.

The plug 15 in Fig. 4 includes an extreme end part 1511 having a surface 2 inclined to the longitudinal axis of the plug. The inclined surface 24- engages and bears against the top rounded end of an elongated cylindrical part which is axially movable within a passage 25 of the body 7 and coaxial with the pin 13.

The operation of the modification of Fig. 4 is the same as that of the first described embodiment of Figs. 1, 2 and 3, and will not be repeated here. However, it should be pointed out that in the modification of Fig. 4, the transverse guide pin 16' is threaded into the extreme endpart 15a of the plug 15 and the outer end thereof fits in a groove or passage 17 formed in the body '7.

The modification of Fig. 5 differs from the embodiments previously described and illustrated in Figs. 1 to 4 in that the plug 15 is enlarged at an intermediate part to form a valve part 27, and the body 7 is formed to pro vide a seat 23 against which the valve part 27 moves when urged to its closed or seated position. In this way, an auxiliary control valve is provided between the main valve member 4 and the region of the body '7 at which the conduit 2th" is connected thereto. The valve part 27 and seat 28 therefor are so positioned with respect to valve member 4 that, when upward movement is imparted to plug 15" by the hand knob 12", the valve part 27 will reachits closed or seated position shortly after the plug 15" allows the pin 18 to move upwardly a sufficient distance to permit the valve member 4 to move to its fully closed position. In other respects, the modification of Fig. 5 is generally similar to the embodiment described above and illustrated in Figs. 1, 2 and 3.

In view of the foregoing, it will now be understood that in each of the embodiments described and illustrated, the

spring

10, 10 or 10", the tension of which is adjusted by the

cap

11, 11 or 11", acts to hold the valve member 4 in its fully open position as long as the pressure of the gaseous fuel is at or below a predetermined pressure. When the pressure of the gaseous fuel exceeds thepredetermined value, which is dependent upon the tension of the

spring

10, 10' or 10", movement is imparted to the

plunger

9, 9 or 9 responsive to the pressure of the gaseous .fuel, such movement of the plunger being efi'ncted against the tension of the spring 10, it) or 10". The tension of the spring 10, 10' or ill?" preferably is adjusted so that it will yield to movement of the plunger 2 9' or 9" at. a fuel pressure which is below the maximum fuel pressure that will occur and desirably at the lowest fuel pressure that is. encountered at a time when the ambient temperature of the surroundings is low.

Let us assume, for example, that under normal temperature conditions the gaseous fuel is discharged from liquefied petroleum gas containers at-apressure of about 7 or 8 kg./cm. and that under lower temperature conditions, which sometimes may be encountered, the gaseous fuel is discharged from the containers at a pressure of about 4 kg./cm. Underthese. conditions, it is desirable to adjust the tension of spring 10- in Fig. l so that the valve member 4 willbefullyopen Whenthe fuel. pressure is about 4 kg./cm. and will move toward its closed position and throttlethe fuel toa lower pressure when it is discharged from the container at a pressure of about 7 or 8 kg./cm. In-this way, gaseous fuel can be supplied to a burner or other appliance at a substantially constant pressure under all operating conditions encountered in practice.

Although particular embodiments of theinvention have been shown and described, it will be apparent that various modifications and changes may be made without depart- 1 ing from the spirit and scope ofthe invention, as pointed out in the following claims.

What is claimed is:

l. A control valve assembly'for controlling the flow of fuel for the burner of an appliance burning a gaseous fuel fed from a fuel container, said assembly containing a valve, housing having a fuel inlet and a fuel outlet, passage means defining a valve seat forming a flow path of the fuel flow from said inlet to-said outlet, a movable valve control member spring biased toward said seat, yieldable pressure responsive means coacting with said movable .valve member to hold'the latter in its valve opening position below a predeterminedpressure of the fuel flow through the valve andto yield for movement of the valve control member toward its closing position in response to a pressure of thefuel flow above said predetermined pressure,-said pressure'responsive means including a cylinder, aplunger slidably supported in said cylinder, a loaded spring means yieldably urging said' plunger to ward said valvev member and an abutment portion on said plunger engaging. thevalve member for controlling the position thereof by the position of the plunger in the cylinder, said plunger exposed to the pressure of said flow in the direction opposite to the direction of the force of said loaded spring means, the position of the plunger being a function of the balance of the spring means and the fuel fiow thereby controlling the valve opening by the pressure of the fuel flow through the valve assembly, said plunger having a threadedv axial bore and said abutment portion includinga plug threaded in said axial bore, the free end of the; plug. engaging saidvalve member, said plunger being rotatable relative to the plug and axially displacing the plugwithin the plunger to vary the position of the valve-memberindependently of the force 'of the spring means and the-fuel flow, the inner wall of the passage being formed with a longitudinal keyway, and said plug being axially guided in said keyway to prevent rotation of the plug upon rotation of the plunger.

2. A control valve assembly for controlling the flow of fuel for the burner of an appliance burning a gaseous fuel fed from afuelcontainer, said assembly containing a valve housing having a fuel inlet and a fuel out let, passage means defining a valve seat forming a flow path of fuel flow from said inlet to said outlet, a-movable valve control member spring biased toward said seat, yieldable pressure responsive means coacting with said valve member. to hold the latter in itsvalve opening position below a predetermined pressure of the fuel flow through the valve and to yield for movement of the'valve control member toward the closing positionin response to a pressure of the fuel flow above said predetermined pressure, said pressure responsive means including a cylinder, a plunger slidably supported in: said cylinder, a loaded spring means yieldably urging said plunger 'toward'said valve member and an abutment portion on said plunger engaging the valve member for controlling the position thereof'by the position of the plunger in the cylinder, said plunger exposed to the pressure of said flow in the direction opposite to the direction of the force of said loaded spring means, the position of the plunger being a function of the balance of the spring means and the fuel flow thereby controlling the valve opening by the pressure of the fuel flow through the valve assembly, said outlet disposed between said plunger and said valve member, an auxiliary valve for controlling the fuel flow through the control valve assembly interposed within the passage between said outlet and said valve member, said auxiliary valve including an auxiliary valve seat formed on the inner wall of the passage and an auxiliary valve control member formed on said abutment portion for movement in unison therewith, the position of the said auxiliary valve control member on the abutment portion being such that it is seated upon its seat immediately following the release of the valve member of the control valve assembly by said abutment portion in response to a fuel pressure above said predetermined value.

3. A control valve assembly for controlling the flow of fuel for the burner of an appliance burning a gaseous fuel fed from a fuel container, said assembly comprising a valve housing having a fuel inlet and a fuel outlet, passage means defining a valve seat forming a flow path of the fuel flow from said inlet to said outlet, a movable valve member spring biased toward closing engagement with said seat to shut ofi the fuel flow, said movable valve member having an abutment part, yieldable pressure responsive means coacting with said valve member to maintain said valve member out of engagement with said seat in response to fuel flow of said valve below a predetermined pressure and to permit movement of said movable valve member toward said seat in response to fuel flow through said valve above said predetermined pressure, said pressure responsive means including a cylinder within said housing, a plunger slidably and rotatably supported within said cylinder, loaded spring means yieldably urging said plunger toward said valve member, one end of said plunger having a threaded axial bore, a plug in threaded engagement within said axial bore, one free end of the plug acting on said abutment part of said valve member controlling the position thereof in response to the position of the plunger in the cylinder, said one end of the plunger being exposed to the pressure of said flow in the direction opposite to the direction of the force of said loaded spring means, the position of the plunger being a function of the balance of the spring means and the fuel flow thereby controlling the opening for the valve member by the pressure of the fuel flow through the valve assembly, and means axially guiding said plug to prevent rotation thereof upon rotation of said plunger for axially displacing the plug within the plunger to vary the position of the valve member independently of the pressure of the spring means and the fuel flow.

4. A control valve assembly as set forth in claim 3, wherein said fuel outlet is disposed between said plunger and said valve member, an auxiliary valve for cutting the fuel flow positioned within the passage between said outlet and said valve member, said auxiliary valve comprising an auxiliary valve seat formed on the inner wall of the passage and an auxiliary valve member carried upon said plug for movement in unison therewith, said auxiliary valve member seating upon its seat immediately following the closing of the spring biased valve member upon the release of the valve member by said plug and displacement of the plug in response to the rotation of the plunger.

5. A control valve assembly as set forth in claim 3, further comprising an intermediate member slidably disposed between said plug and said abutment part, said plug acting on said abutment part through said intermediate member, said plug being inclined at an angle to said intermediate member, said plug and said intermediate member having coacting slanting surfaces whereby an axial displacement of the plunger controls the position of said valve member through said intermediate member.

References Cited in the file of this patent UNITED STATES PATENTS 1,011,093 Tanner et a1. Dec. 5, 1911 1,276,878 Coy Aug. 27, 1918 1,361,636 Stage Dec. 7, 1920 2,226,810 Ensign et a1. Dec. 31, 1940 2,235,210 Fonseca Mar. 18, 1941 2,255,747 Jones Sept. 16, 1941 2,569,023 Sanford Sept. 25, 1951 2,615,287 Senesky Oct. 28, 1952 2,687,018 Baldwin et a1. Aug. 24, 1954