US1992048A - Controller - Google Patents

Description

P. C. TEMPLE Feb. 19, 1935.

CONTROLLER Filed Dec. l2, 1932 :NvENToR PA Uf.. C'. TEMPLE BY 'L l Qtr/JM: &7. @741W ATTORNEY i Patented Feb. 19,l 191,55 l I UNITED STATES PATENT oFFlcE CONTROLLER Paul c. Temple, Deeatur, lu., assigner 'te A. w. Cash Company, Decatur, Ill., a, corporation of Delaware Aepueauen December 12, 1932, serial No. 646,835

11 claims. (ci. 137-144) This', invention relates to controllers, and more Fig. 2 is an enlarged section taken on the line Y particularly to a valve mechanism which, in the 2-2 of Fig. 1;

preferred construction, is arranged to be ac- Fig. 3 is a section on the line 3 3 of Fig. 1; tated automatically in accordance with varia- Fig. 4 is a fragmentary top plan view of .the 5 tions in the pressure of a controlling fluid. automatic controller, partially broken awayl for 5 It is one object of the invention to provide a cleamess of illustration; simple, compact and inexpensive automatic con- Fig. 5 is a perspective view of a screw plug,'

troller which willbe extremely sensitive in opshown in longitudinalsection; eration and which will respond to the slightest Fig. 6 lis a perspective view of an inlet seat change in the controlling iluid pressure. member, shown in longitudinal section; 10

It is a further object of the invention to pro- Fig. 7 is a perspective view of an exhaust seat vide an automatic controller which will operate member, shown in longitudinal section; efficiently throughout a long life of usefulness,` Fig. 8 is a perspective view o1 the valve opand which will be substantially unaffected by erating stem; and any wear which may occur. Fig. 9 is a diagrammatic view on a' small scale l5 It is a further object of the invention to proshowing thev automatic controller connected to vide an automatic controller which may be readother apparatus. I ily connected to respond to a controlling uid The embodiment illustrated comprises a holpressure either above or below atmospheric preslow valve body or casing 10 provided with an E0 sure, or to the difference between two fluid presinlet opening 11, an outlet or exhaust opening 12, 20 sures. and two openings 14 and 15 which I will call, for It is a further object of the invention to prolack of a better term, cylinder openings. Thesevide a simple and compact automatic controller various openings are all shown provided with in which all moving parts are fully enclosed and screw-threads for convenience in connecting protected. pipes thereto. The interior of the casing 10 is 25 It is a further object of the invention to prodivided by suitable partitions into an inlet chamvide a controller comprising a valve mechanism ber 16, an exhaust chamber 18, and two interof the seating type which will have a minimum mediate chambers 19 and 20. The exhaust of parts and which will be simple and inexpensive chamber is located between the intermediate to manufacture. chambers, and the inlet chamber is U-shaped 30 It is a further object of the invention to proand arranged with its end portions adjacent to vide a controller comprising a valve mechanism the intermediate chambers. The inlet opening 11 so constructed that all parts subject to wear can leads directly into the inlet chamber 16, and the be readily replaced without disturbing the pipexhaust opening 12 leads directly from the exing connections. haust chamber 18. The cylinder openings 14 35 It is a further object of the invention to proand 15 communicate directly with the intermevide a controller comprising a Seating- type fourdiate chambers 19 and 20 respectively. Inlet way valve mechanism in which two valves serve ports or passages 22 and 23 connect the inlet to control the flow through four ports. chamber 16 with the intermediate chambers 19 It is a further object of the invention to` proand 20 respectively, and exhaust ports or pas- 40 vide a controller comprising a seating- type valve sages 24 and 25 connect the exhaust chamber mechanism which will operate smoothly at all with the intermediate chambers 19 and 20 retimes and which Will be free from all tendency spectively. In the preferred construction these to chatter. ports 22, 23, 24 and 25 are arranged in direct With these and other objects in view, as will axial alignment. 45 be apparent to 15h05@ Skilled in the art, the in- The ilow of uid through the casing 10 is convention resides in the combination of parts set 1 trolled by two valves 27 and 23,-Whieh are prefforth in the SDeCiCaOh and Covered by the erably spherical in shape. Valve 27 is located claims appended hereto. between ports 22 and 24, and valve 28 is located Referring to the drawing illustrating one embetween ports 23 and 25. These valves are con- 50 bodiment of the invention, and in which like reftrolled by a reciprocable valve stem 29 having erence numerals indicate like parts, its end portions slidable in the exhaust ports 24 Fig. 1 is a section through an automatic conand 25. The end portions of the stem 29 are cut troller, the section being taken on the line 1-1 away at 3D (Fig. 8), so that the exhaust ports of Fig. 4; will not be completely obstructed by the stem. 55

If the fluid to be controlled is a liquid, such as water or oil, the valve stem is preferably made long enough to hold the valves 27 and 28 slightly olf the exhaust seats when the'stem is in its central or neutral position. This is particularly desirable when the valve stem is arranged to be actuated by an automatic pressure responsive device, since it removes a large part of the unbalanced load on the valves and makes the controller more sensitive. However, if the fluid to be controlled is a gas, such as compressed air, the valve ports can be made much smaller and the unbalanced load will therefore become of little importance. In such acase the valve stem is preterably made slightly shorter, so that both valveswill close against the exhaust seats when the valve stem is in its neutral position. This prevents Aany loss of fluid to the exhaust so long as the valve stem remains in this position. It will be understood that the valve stem is not fastened to the ball valves, Abut merely pushes against them. Hence any inaccuracy or misalignment which may occur in the actual construction will not prevent the valves from seating tightly.

In order that my improved four-way valve mechanism may be conveniently manufactured and assembled, I prefer to form the various inlet and exhaust ports in separate parts which are removably mounted in the casing 10. As illustrated. the exhaust ports 24 and 25 are formed in flanged hollow cylindrical members 32 and 33 respectively which are held ilrmly in position by means of plugs 34 and 35 screw-threaded to the casing 10. The plugs 34 and 35 are arranged in direct axial alignment with the members 32 and 33. The inlet ports 22 and 23 are formed in flanged cylindrical members 37 and 38 which are screw-threaded to the interior bore of the members 32 and 33. The plugs 34 and 35 are recessed axially as shown at 39 to clear the flanged ends of the inlet seat members 37 and 38, and radial openings 40 are provided to communicate with the recesses so that the fluid flow.to the inlet ports will not be obstructed. Radial openings 42 are provided in the exhaust seat members 32 and 33 to establish communication between the interior of these members and the adjacent intermediate chambers.

It will now be seen that if fluid is supplied under pressure to the inlet chamber 16, and the valve stem 29 is moved upwardly, valve 27 will close the inlet port 22. At the same time, the iluid pressure will force valve 28 upwardly to close the exhaust port 25. Fluid can therefore ilow from the inlet chamber 16 to the intermediate chamber 20, and iluid can also flow from the intermediate chamber 19 to the exhaust chamber 18. If the valve stem is moved downwardly to its other extreme position, the inlet chamber will be connected with the intermediate chamber 19, and the intermediate chamber 20 will be connected with the exhaust chamber.

In the construction illustrated, the valve stem 29 is arranged to be actuated automatically by means of a lluid pressure responsive diaphragm 44 which is connected to the valve stem by means of a lever 45 of the first class. This lever is pivotally supported by means of a small ilexible diaphragm 46 which serves both as a fulcrum for the lever and as one wall of the exhaust chamber 18. As shown in the drawing, the lever 45 extends through a central opening in the diaphragm 46, and a nut 47 is provided to clamp the diaphragm against a shoulder on the lever. This diaphragm 46 is preferably formed from a thin Aend of the lever is positioned within a transverse opening 56 (preferably rectangular in cross-section) formed in a boss 57 whichvprojects downwardly from the central portion of a lower pressure plate 59. Both ends of the lever are preferably spherical in shape to avoid friction and possible binding. The central portion of the main diaphragm 44 is clamped between the lower pressure plate 59 and an upper pressure plate 60, these plates being fastened together by a central stud 61 and a nut 62. The main diaphragm is clamped at its periphery between the diaphragm casing 49 and a flanged upper cover plate 64 which is fastened to the casing 49 by means of bolts 65.

It will now be seen that the main diaphragm 44 divides the space enclosed by the casing 49 and the cover plate 64 into an upper chamber 67 and a lower chamber 68. The cover plate 64 is provided with an opening 69 leading to the chamber 67, and the casing 49 is provided with an opening 70 leading to the chamber 68. These openings are shown screw-threaded for convenience in connecting pipes thereto. A rcontrolling Huid pressure may be applied to either or both of these chambers.

In order to support the main diaphragm against the controlling fluid pressure, I have shown a coiled tension spring 72 arranged in a vertical position above the center of the diaphragm with its lower end connected to the stud 61. The upper end of the spring is fastened to a nut 73 which is mounted on a vertical screw 74. This screw is rotatably supported in a housing 75 which is fastened to the cover plate 64 by means of screws 76, and which serves to enclose the spring. The head 7'7 of the screw 74 is accessible at the top of the housing 75, so that the screw can be rotated to move the nut 73 vertically and thus vary the tension of the spring. The housing 75 prevents the nut from turning.

In case the controlling fluid pressure to which the main diaphragm is subjected is large enough to cause an excessive load on the valve seats or fulcrum diaphragm, I prefer to provide a connection between the main diaphragm and the valve stem which will yield if the load materially exceeds that necessary to actuate the valves and which will thus allow the main diaphragm to continue its movement to the limit of travel. This yieldable connection is preferably obtained by providing a flexible joint in the long arm of the lever 45, and utilizing a spring to hold the joint normally rigid. As illustrated, the lever 45 is formed in two parts having flanges and 8l at their adjacent ends. These flanges are normally held in contact by means of a coiled spring 82 which is compressed against the ilange 8l by a hollow cylindrical Acap 83 screw-threaded to the ilange 80. If an excessive load is applied to the lever 45, the flange 81 will tip with respect to the flange 80, thus `compressing the spring 82 still further. This will prevent damage to any of the parts.

The automatic controller which I have described can be used in a great many ways. It is particularly suitable for actuating a doubleacting piston in response to a controlling fluid y pressure or pressurediferential. If the controlling pressure is above atmospheric it will be applied to the chamber 67, the chamber 68 being left open. If the controlling pressure is below atmospheric it will be applied vto the chamber 68, the chamber 67 being left open. If pressure differential is to be used for control, the higher pressure will be applied to the .fphamber 6'? and the lower pressure will be applied to the chamber 68. By way of example, I have illustrated in Fig. 9 one typical installation in which my automatic controller is arranged to maintain a constant rate of fluid ow in a pipe 85 by regu.- lating a butterfly valve 86. An orifice plate 87 is mounted in the pipe 85, and the pressure differential between opposite sides of the plate is used as a measure of the rate of flow. yThe pressure on the upstream side of the orifice plate is brought to the chamber 67 through a pipe 89, and the pressure on Ithe downstream side is brought to the chamber 68 through a pipe 90. A double-acting piston in arcylinder 92 is connected by a rod 93 to the arm 94 of the butterfly valve 86. The upper end of the cylinder 92 is connected by a pipe 96 to the intermediate chamber 19 of the controller,` and the lower end of the cylinder is connectedby a pipe 97 to the intermediate chamber 20 of the controller. The

` inlet chamber 16 is supplied with a suitable fluid under pressure through a pipe 98.

The operation of the invention will now be apparent from the above disclosure. So long as the flow in the pipe remains constant at the rate for which the automatic controller is'adjusted, the pressure drop across the orifice plate 87 will also remain constant, and the controller will remain in neutral position, holding the butterfly valve 86 stationary. If for any reason the flow in the pipe 85 should increase slightly, the pressure drop across the orifice plate will also increase, thus moving the main diaphragm 44 downwardly and rocking the lever 45. ,This will actuate the four-way valve and admit fluid under pressure through the pipe 9'7 tothe lower end of the cylinder 92, while at the same time exhausting the upper end through the pipe 96, thus raising the piston and closing the butterfly valve 86 until the desired flow rate is once more established. The controller will then return to neutral, and the butterfly valve will remain stationary inits new position. Similarly, a decrease in the rate of flow will cause upward movement of the main diaphragm, downward movement of the piston, and opening of the butterfly valve to restore the desired flow.

It will be noted that all the moving parts of my improved controller are fully enclosed and protected from dust and dirt. There are no stuffing boxes to cause friction and erratic operation. The four-way valve is simpler and requires fewer parts than any prior construction of which Iam aware. This valve is practically frictionless and can be actuated with a minimum of power. The ball valves close against the high pressure, and this feature is of great value in eliminating all tendency toward chattering and snap action. By removing the plugs 34 and 35 it is possible to replace the valves and valve seats without disturbing any piping connections. The fulcrum diaphragm 46 provides a frictonless bearing for the lever 45, and is one important factor which contributes to the great sensitivity of the controller. This fulcrum diaphragm also acts as an effective seal to prevent leakage of fluid from the exhaust chamber 18. The fluid ter of an inch in diameter, the total movement of eachvalve is only about ten thousandths of an inch. Any wear which may occur on the valve seats will be` taken up automatically by a slightly increased valve movement. The entire construction is simple, compact and inexpensive.

Having thus described my invention, what I claim as new and desire to secure by Letters Patentv is:

1. A controller comprising means forming two inlet ports for fluid and two exhaust ports for fluid, each exhaust port being located opposite an inlet port, means to supply fluid under pressure to both the inlet ports, two `seating-type valves, each valve being reciprocable between one ,of the inlet ports and the opposing exhaust port to control the flow through the ports, and common means for actuating both the valves, said valve actuating means having portions extend- .ing through the exhaust ports to contact with the valves but not attached thereto.

2. A controller comprising means forming two inlet ports for fluid and two exhaust ports for fluid, the ports being all aligned with each exhaust port located opposite an inlet port, means to supply fluid under pressure to both the inlet ports, two seating-type valves, each valve being reciprocable between one of the inlet ports and the opposing exhaust port to control the flow through the ports, and common means for actuating both the valves, said Valve actuating means having portions extending through the exhaust ports to contact with the valves but not attached thereto.

3. A controller comprising means forming two inlet ports for fluid and two exhaust ports for fluid, the ports being all aligned with the exhaust ports between and opposed to the inlet ports, means to supply fluid under pressure to both the inlet ports, two seating-type valves, each valve being reciprocable between one of the inlet ports and the opposing exhaust port to control the flow through the ports, and a reciprocable valve stem located between the valves to actuate the same, the ends of the valve stem extending through the exhaust ports to contact with the valves but not atached thereto.

4. A controller comprising means forming two inlet ports for fluid and two exhaust ports for fluid, the ports being all aligned with the exhaust ports between and opposed to the inlet ports, means to supply fluid under pressure to both the inlet ports, two seating-type valves, each valve being reciprocable between one of the inlet ports and the opposing exhaust port to control the flow through the ports, a reciprocable valve stem located between the valves to actuate the same, the ends of the valve stem extending through the exhaust ports to contact with the valves but not attached thereto, and a pivotally mounted lever connected to the valve stem at a point between the valves.

5. A controller comprising means forming two inlet ports for fluid and two exhaust ports for fluid, the ports being all aligned with the exhaust ports between the inlet ports, each exhaust port being located opposite an inlet port, means to supply fluid under pressure to both the inlet clprocable between one of the inlet ports and the opposing exhaust port to control the iiow through the ports, and a reciprocable valve stem to actuate the valves, the ends of the valve stem extending throughA the exhaust ports to contact with the valves but not attached thereto.

6. A'controller comprising means forming four aligned ports for fluid, the ports being arranged in pairs with the ports of each pair opposed, two seating-type valves, each valve being reciprocable between one pair of ports to control the ow therethrough, a reciprocable valve stem located between the valves to actuate the same, and a pivotally mounted lever connected to the valve stem ata point between the valves.

'7. A controller comprising means forming two inlet ports for iluid and two exhaust ports for fluid, the ports being all aligned with each exhaust port located opposite an inlet port, two seating-type valves, each valve being reciprocable between one of the inlet ports and the opposing exhaust port to control the flow through the ports, a reciprocable valve stem located between the valves to actuate the same, and a pivotally mounted lever connected to the valve stem at a point between the valves.

8. A controller comprising means forming two inlet ports for iluid and two exhaust ports for iiuid, the ports being all aligned with the exhaust ports between and opposed to' the inlet ports, two seating-type valves, each valve being reciprocable between one of the inlet ports and the opposing exhaust port to control the flow through the ports,.rneans providing an exhaust chamber between the exhaust ports, the exhaust ports leading into the exhaust chamber, a reciprocable valve stem between the valves to actuate the same, a exible diaphragm forming one wall of the exhaust chamber, a lever pivotalports, two spherical valves, each valve being rely supported bythe diaphragm, one end of the lever being connected to the valve stem, and a vfluid pressure responsive diaphragm connected to the other end of the lever.

9. A controller comprising'a casing shaped to provide an inlet chamber, twointermediate chambers, and an exhaust chamber, four-way valve mechanism to control the iiow through the chambers, a flexible diaphragm forming a wall of the exhaust chamber, a lever pivotally supported by the diaphrag one end of the lever being connected to the valve means, and a iluid pressure responsive diaphragm connected to the other end of the lever.

10. A controller comprising a valve casing shaped to provide a chamber for iluid, valve means to control the flow through the chamber, a diaphragm casing. a flexible diaphragm clamped at its periphery between the valve casing and the diaphragm casing, the diaphragm torming a wall of the chamber, a lever ypivotally supported bythe diaphragm, one end of the lever being connected to the valve means, a cover plate, a fluid pressure responsive diaphragm clamped at its periphery between the cover plate and the diaphragm casing, and connections between the iiuid pressure responsive diaphragm and the other end of the lever.

11. A controller comprising a casing shaped to provide a chamber for fluid, valve means to control the ow through the chamber, a ilexible diaphragm forming a wall of the chamber, a lever pivotally supported by the diaphragm and connected to the valve means, the lever having a iiexible joint therein, a spring arranged to hold the joint normally rigid and yet allow the Joint to flex in case the force applied to the lever is excessive, and a fluid pressure responsive device arranged to actuate the lever.

PAUL C. TEMPLE.

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