US1752534A - Control device - Google Patents

Description

April 1, 1930.

G. w. M KEE CONTROL DEVICE Filed March 22, 1926 2 Sheets-Sheet l 47 mmufi April 1, 1930. (5. w. MQKEE: v 1,752,534

CONTROL DEVICE Filed March 22, 1926 2 Sheets-Sheet 2 7 1 pg w I l! 1 5 H.

LAW 42 Patented Apr. 1, 1930 UNITED STATES GARNET W. MOKEE, OF ROCKFORD, ILLINOIS common DEVICE Application filed March 22, 1926. Serial No. 96,407.

The present invention relates to improvements in control devices for regulating the flow of fluids, and more particularly to devices for automatically regulating the flow of air, fuel, or both to a burner in accordance with temperaturevariations at the burner, the device being designed to increase the flow upon a decrease in the temperature and to decrease the flow upon an increase in the temperature, from a predetermined point.

One object of the invention is to provide a novel control device having a butterfly valve for controlling the flow of fluid, thereby obtaining a fine regulation and reducing to a minimum the impediment to flow by the valve when open.

A further object is to provide a new and improved control device of the above character having novel means for actuating the valve. I

A general object is to provide a novel control device of the above character which is simple and inexpensive in construction, which is accurate and etlicient in operation, and which is not liable to get out of order when in use.

Further objects and advantageswill become apparent as the description proceeds.

In the accompanying drawings, Figure 1 is a vertical section taken along line 11 of Figure 2 of an apparatus embodying the features of my invention.

Figure 2 is a front elevation thereof.

Fig. 3 is a fragmentary section taken along line 3-3 of Figure 1.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawings and will herein describe in detail the preferred embodiment thereof, but it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but aim to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in theappended claims.

Referring more particularly to the drawings, 4 represents a fluid supply pipe or line' which is adapted to transmit fluids, such as air, fuel, or a mixture of air and fuel, from a source of supply to a point of use, such for example as a suitable burner (not shown). In the present instance, it may be assumed that air under pressure, which is to be mixed in a proper proportion with fuel for the burner, flows through the pipe 4 in the direction of the arrows (see Fig. 1). Interposed in 'the supply pipe 4 is a butterfly valve 5 which is automatically controlled to'reduce the flow of air as the temperature at the burner rises above a predetermined point and to permit a large flow of air when said temperature falls below said point.

The butterfly valve 5 comprises a flat circular disk which is centrally secured to a shaft 6 extending diametrically through a fitting 7 in the pipe 4. Of the shaft 6, one end is journalled in a closed tubular projection 8, and the other extends outwardly through a bearing 9, on the fitting 7.

The shaft 6 is operatively connected to a control mechanism which comprises as an operating element a, longitudinally movable plunger 10. In the present instance, a split clamp sleeve 11 is secured to the outer end of the shaft 6, and is formed integral with a gear segment 12 meshing with a longitudi nal gear rack 13 on the plunger 10.

Of the plunger 10, one end extends slidably and centrally through adiaphragm casso ing comprising two bowl- shaped sections 14 and 15 secured together by bolts 16, and the other end extends slidably through an up standing e'ar 17 which is formed on a lateral bracket 18 secured to the section 14. Threaded onto the plunger 10 at opposite sides of the car 17 are two sets, 19 and 20, of lock nuts which serve to limit the longitudinal movement of the plunger and which are adjustable to change the range and extent of this movement. Rotation of the plunger 10 is prevented by a pin 21 extending laterally therefrom into engagement with a notch 22 formed in the adjacent surface of the bracket 18. The casing is mounted on the fitting 7 by means of a plate 23 secured to the section 14.

A flexible diaphragm 24 of suitable material is clamped between the casing sections 14 and 15, and serves to form therewith 8.

chamber 25 and a pressure chamber 26, respectively. The chamber 25 communicates with the atmosphere through one or more openings 27 formed in the section 14. The diaphragm may be secured to the plunger 10 in any suitable manner, and in the pres ent instance is held between two annular disks 28 clamped together by nuts 29 on a threaded enlargement 30 of the plunger.

Mounted on one end of the plunger 10 between a washer 31 on the latter and the outside of the casing section 15 is a coil spring 32 which tends to move the plunger to the right, as viewed in Figure 1, to open the valve 5. The spring 32 is enclosed by a cylindrical cap 33 which is threaded into an annular flange 34 formed on the casing section 15.

To automatically control the position of the valve 5, the supply pipe 4 connected through a small by-pass pipe 35 to a pipe 36. of which one end opens into the pressure chamber 26 and the other end communicates with a. fluid escape valve adapted to be opened and closed by a thern'lostatically controlled device in accordance with predetermined temperatures at the burner. \Vhen the escape valve is open, the pressure fluid from the by-pass pipe 35 escapes to the atmosphere, thereby preventing pressure from building up in the pressure chamber 26. When the fluid valve is closed, the pressure fluid however enters the chamber'26. and moves the diaphragm 24 against the action of the spring 32 to close the valve 5.

In the present instance, the fluid escape valve comprises a tube 37 which is secured to the outer end of the pipe 36. and the bore of which is formed with a valve seat 38 communicating at one side with said pipe and at the other side with one or more ports 39 opening to the atmosphere. The valve seat 38 is adapted to be closed by a needle valve 40- having a stem 41 which extends upwardly into a casing 42 secured to the upper end of the tube 37. A coil spring 3 encircles the valve 40, and tends to move the latter away from the valve seat 38. Housed in the casing 42 is a solenoid 44 having a vertically movable core 45 provided at its lower end with a weight 46. This weight engages the upper end of the valve stem 41, and is adapted to move the valve 40 against its seat 38 when the solenoid 44 is deenergizcd. The solenoid 44 is connected in series with a source of electrical current 47 and a thermostatic element 48 adapted to close and open the circuit respectively as the temperature falls below and rises above a predetern'iined point. The

thermostatic element 48 is positioned in the furnace heated by the burner, a fragment of the furnace shell being shown in dotted lines at 49.

Manually adjustable means is provided to regulate the pressure in the chamber 26 when the port 39 is cut oflf from the pipe 36, and

thereby to regulate the opening and closing movements of the valve 5. This means comprises a valve fitting 50 opening into the tube 37 below the valve seat 38, a longitudinally slotted nipple 51 controlling the passage through said fitting, and a cap 52 adjustable on said fitting and formed with a valve seat 53 having a wedge engagement with the slotted end of said nipple. By adjusting the cap 52, the effective opening through the nipple 5i can be varied to control the pressure in the chamber 26.

Interposed in the by-pass pipe 35 is a strainer for the pressure fluid from the pipe 4. Preferably this strainer-consists of a hollow fitting 54 formed with a chamber 55 and a passage 56 communicating respectively with the pipe 4 and the pipe 36. Positioned in the chamber 55 is a cylinder screen 57 one end of which is closed by an apertured plug 58 fitting over the opening to the passage 56. The other end of the screen 57 is closed by a removable plug 59 which holds the screen curely in place and which may be removed to obtain access to the chamber 55.

In operation, it the temperature is below the predetermined point, the solenoid 44 will be energized, thereby permitting the valve 40 to be held away from the seat 38 and hence permitting pressure fluid from the by-pass pipe 35 to escape to the atmosphere through the port 39. As a result, the pressure in the chamber 26 is relatively low, so that the spring 32 maintains the valve 5 in open position, thereby permitting a maximum flow of pressure fluid through the pipe 4 to the burner. This condition is shown in Figure 1. The extreme open position of the valve 5 can be varied by adjusting the nuts 19. It now the temperature rises above the predetermined point. the solenoid 44 will be deenergizcd, and the weight 46 will drop, thereby moving the valve 40 against the seat 38 to cut oil" the port 39. Pressure fluid from the bypass pipe 35 will thereupon enter the chamber 26. and will move the diaphragm 24 against the action of the spring 32 to close the valve 5. The extent of this movement may be varied by adjusting the nuts 20.

The pressure in the chamber 26 may be regulated by adjusting the cap 52, and hence excessive pressure against the diaphragm can be prevented.

It will be evident that I have provided an efficient and simple means for automatically regulating the flow of pressure fluid to the point 01 consumption. in accordance with conditions resulting therefrom. By providing a butterfly valve a minimum restriction to the flow results when the valve is open, and a gradual and uniform opening and closing effect is obtainable.

I claim as my invention:

1. A control device having, in combination with a supply pipe, a butterfly valve in said pipe and having a stem projecting from one side thereof, a casing, a pressure responsive member in said casing and dividing said casing into a chamber open to the atmosphere, and a pressure chamber, means operatively connecting said member to said stem, means tending to move said member into said pressure chamber to open said valve, by-pass means connecting said pipe with said pressure chamber, a port in said last mentioned means for permitting the escape of pressure fluid and thereby tending to prevent pressure from building up in said pressure chamber, and manually adjustable means for adjusting the effective opening through said port to control the pressure in said pressure chamber.

2. A control device having, in combination with a supply pipe, a butterfly valve in said pipe and having a stem projecting from one side thereof, a casing. a diaphragm in said casing and having a plunger projecting through both sides of said casing. said diaphragm dividing said casing into a chamber open to the atmosphere, and a pressure chamber. gear means ope 'atively connecting one end of said plunger with said stem. means for limiting the movement of said plunger, spring means on the other end of said plunger tending to flex said diaphragm into said pressure chamher to open said valve, by-pass means connectmg said pipe with said pressure chamber. a port in said last mentioned means for permitting the escape of pressure fluid to prevent pressure from building up in said pressure chamber. and automatic means operable to cut ofl said port to cause pressure to build up in said pressure chamber and thereby close said valve.

3. A control device having, in combination with a fluid supply pipe, a butterfly valve, in said pipe, a casing having a chamber and rigidly mounted relative to said pipe, a diaphragm forming a wall of said chamber, means operatively connecting said diaphragm to said valve to open and close the latter upon movement of said diaphragm in opposite directions. by-pass means connecting said chamher with said pipe for admitting pressure fluid to flex said diaphragm to close said valve, spring means tending to flex said diaphragm to open said valve, a bleed passage opening from said by-pass means, and thermostatically controlled means automatically operable to control said bleed passage so as to control the pressure in said chamber in accordance with predetermined conditions resulting from the flow of fluid through said pipe.

4. A control device having, in combination with a fluid supply pipe, :1 butterfly valve pivotally mounted in said pipe and having a stem projecting from one side thereof. a gear segment rigidly mounted on said stem. a casing rigidly mounted with relation to said pipe, a diaphragm in said casing, said diaphragm having a central plunger extending through said casing, gear means on one end of said plunger meshing with said gear segment, spring means on the other end of said plunger and tending to move said diaphragm in one direction, and automatic means for controlling the admission of pressure fluid to said casing to move said diaphragm in the other direction in accordance with predetermined conditions resulting from the flow of fluid through said supply pipe.

5. A control device having, in combination with a fluid supply line, a pivotal valve controlling the passage through said line, a casmg, a pressure responsive member movable in said casing, means operatively connecting said member to said valve, means tending to move said member in a direction to open said valve, means automatically operable to direct pressure fluid from said pipe into said casing to move said member in a direction to close said valve, and adjustable means limiting the movementof said member.

6. A control device having, in combination with a supply pipe, a butterfly valve pivotally mounted in said pipe, a casing, a diaphragm in said casing, gear means operatively connecting said diaphragm to said valve to open and close the latter upon movement of said diaphragm in opposite directions, automatic means for controlling the position of said'diaphragm in accordance with temperature variations, and means for adjusting the extent of movement of said diaphragm in each direction.

7. A control device having, in combination with a supply pipe, a butter-fly valve 1n said pipe and having a, stem projecting from one side thereof, a casing, a pressure responsive member in said casing and dividing said easing into a pressure chamber and a chamber open to a predetermined outside pressure, meansoperatively connecting said member to said stem, means tending to move said member into said pressure chamberto actuate said valve in one direction, means for admitting pressure fluid to said pressure chamber to actuate said valve in the other direction, a port in said last mentioned means for permitting the escape of pressure fluid to prevent pressure from building up in said pressure chamber, and means automatically operable to out 01f or to open said port.

8. A control device having, in combina tion with a supply pipe, a valve in said pipe, a member projecting laterally therefrom, a casing having a pressure chamber, a pressure responsive element forming one wall of said chamber, a plunger secured to said element, gear means operatively connecting said plunger and said member, spring means tending to move said element into said pressure chamber, by-pass means connecting said pipe with said chamber, a port in said last mentioned means for permitting the escape of pressure fluid to prevent pressure from building up in said pressure chamber, and automatic means operable to cut off said port so is to cause pressure to build up in said cham- 9. A control device having, in combination with a supply pipe, a valve member for controlling the flow through said pipe and having a stem projecting therefrom, a casing, a pressure responsive member in said casing, means operatively connecting said member to said stem, means tending to move said pressure responsive member in one direction to actuate said valve member in one direction, by-pass means connecting said pipe with said casing to impress a pressure against said pressure responsive member tending to move the latter in the other direction to actuate said valve member in the other direction, means for permitting the escape of pressure fluid from said by-pass means thereby tending to prevent pressure from building up in said casing, and manually adjustable means for adjusting said last mentioned means to 5 control the pressure in said casing.

In testimony whereoflI have hereunto affixed my signature.

GARNET W. MoKEE.

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