US2535617A

US2535617A - Control mechanism for pumps

Info

Publication number: US2535617A
Application number: US7407A
Authority: US
Inventors: William C Westbrook
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-02-10
Filing date: 1948-02-10
Publication date: 1950-12-26
Anticipated expiration: 1967-12-26

Description

' 1950 w. c. WESTBROOK CONTROL MECHANISM FO R PUMPS 2 Sheets-Sheet 1 Filed Feb. 10, 1948 w m m m VW/fz'am C VVes/braak Patented Dec. 26, 1950 UNITED STATES FATENT OFFICE;

11 Claims.

This invention relates to mechanisms for controlling the speed and pressure of pumps and more particularly of stroke pumps that are onerated by steam, air, or natural gas as a motivatin pressure fluid.

In the pumping of fluids, such as oil. water or the like with stroke pumps, these pumps generally are operated by steam, air or natural gas as the motivating fluid. Stroke p mps operated by some such motivating fluid. have long been in general use in oil fields, refineries, water works and various other industries to which the use of such a pump is adapted.

Heretofore, however, such pumps have required constant attention in order to maintain them at correct o erating speed, to maintain an everpre ent supply of fluid to be pumped, and to maintain a constant discharge pressure. If one or more of these factors were not properly maintained the results required of the pump were hampered and the equipment damaged.

Various regulators have been pro o ed heretofore, and when used under favorable conditions, have been reasonably satisfactory, however. few installations can be made under completely satisfactory conditions and therefore the results of their use have not been satisfactory.

The actuating mechanism of the present invention is connected to a control valve within the motivating fluid supply line of a stroke pump, and is designed to o erate automatically to meet and maintain. the speed and pressure reouirements of the pump. It may be set so that the operating speed of the pump will not vary, whether the pump is o erating at full capacity or when it is not pumping fluid. Provision is also made for maintaining sufficient speed to sustain a. pre determined pressure as long as the fluid being pumped is supplied to the intake. Furthermore, the discharge pressure is controlled to prevent it becoming greater than a predetermined set pressure.

The use of the present control mechanism insures uniform operating speed to the pump even though the fluid being pumped becomes exhausted. The mechanisms in general use heretofore have controlled t e speed of the pump by a constant supply of fl id being pumped, but if the fluid being pumped became exhausted, the pump speed often became so great that the pump mechanism would tear itself to pieces.

The present control mechanism for the pump system is connect d to a member on the pump which imparts mechanical movement for t e oneration of an air pump, which pump supplies air for controlling the speed of the pump through a diaphragm control valve, as will be more fully described hereinafter. Provision is also made for controlling the maximum speed of the pump in accordance with the pressure of the fluid being pumped.

The primary object of this invention is to provide a device for controlling maximum speed of a pump and a maximum output pressure thereof.

Another object of this invention is to provide a pump having an auxiliary air pump thereon to supply air pressure independently, for actuating a control. valve for controlling the maximum speed and maximum pressure of a pump.

Another object of this invention is to provide a control mechanism for pumps that will control the discharge pressure of the pump within a predetermined limit, and in event of a drop in pressure below the predetermined point, the mechanism will effectively control the speed of the pump and in so doing. prevent excess speed which would result in damage and undue wear to the pump.

A still further object of this invention is to provide a pressure shut-off mechanism that controls the exhaust supply of pressure of the pressure generating system so as to effectively control the operating speed of the pump.

Yet another object of the invention is to provide a regulating system for a stroke pump, the mechanism of which provides for independent adjustment of t e speed of the pump and for controlling the discharge pressure thereof.

The present mechanism provides an auxiliary air pump system which is a separate and independent mechanism that is att ched to the motivating fluid supply line of a stroke pump, and which generates an independent pressure system for actuating the control valve which directs steam or gas to the motor end of the pump. Furthermore, provision is also made for utilizing the output pressure of the pump for operating a metering device. which device, in turn, causes the pressure from the generating sy tem to actuate the motor control valve to the pump so as to maintain the motivating fluid thereto in accordance with the requirements of the output pressure Of the pump and with the motor operating part of the pump.

An embodiment of this invention is illustrated in the accompa ying drawings in which:

l is a side elevat onal v ew of a stroke pump showing t e control mechanism. as connected to the motivating fluid line;

end bymeans of a hook 4|.

Fig. 2 is a sectional view of a pressure generating and control mechanism taken on the line 2-2 of Fig. 3;

Fig. 3 is an elevational view thereof with parts broken away and shown in section to more clearly bring out the details of construction;

Fig. 4 is a fragmentary perspective view of a portion of the control mechanism with parts broken away and shown in section to show details of construction; and

Fig. 5 is a sectional View taken on the line 5-5 of Fig. i, looking in the direction indicated by the arrows and showing a fragmentary portion of the fluid control supply system.

With more detailed reference to the drawing, the numeral l designates generally a stroke pump, which pump is usually of the duplex type, that is, having two steam cylinders and. two fluid pump cylinders. This pump has a power head 2 at one end and a pump head 3 at the opposite end thereof. The usual power pistons and pum pistons within therespective cylinders are interconnected by pump rods 4, which pump rods operate the usual slide rods 5 by means of arms 6. The arms 6 are connected to a rocker shaft l to which a bifurcated arm 8 is attached. The bifurcated, upright arm 8 operates an air pump rod 9, which pump rod 9 carries the conventional cups H3 so as to pump air, as will be more fully described hereinafter.

Secured to the pump I is a pressure generating and control unit generally designated at H, which unit has an air cylinder i2 therein valved with intake valves i3 at either end thereof and exhaust valves i 1 at either end thereof. preferable to have theair cylinder clamped be tween heads I5 to prevent endwise movement, and boltsv It are provided to clamp pipes ii and cylinder l2 upward against the bottom of control unit II. This arrangement permits of ready assembly and disassembly of the parts for servicing, maintenance and repair.

' Th air inlet is provided at 58 to direct air through pipe I? and valve it into cylinder H2. The exhaust valves M are provided to permit air to be discharged into reservoir id, as shown in Figs. 2 and 3. The reservoir as is provided with a pressure gauge 2!! and a relief valve 2 i, so the pressure within the reservoir may be quickly and accuratelydetermined, and in event the pressure exceeds a predetermined amount, the relief valve 2! will permit the escape of excess pressure. A bolt 22 has a passage 23 therein, which. passage connects with a transverse passage 2 to direct air pressure into tubular member 2%. The tubular member 25 has a valved orifice 2? at the upper end thereof which orifice is adapted to be closed by a valve 28. A guide rod 29 protrudes downward through tubular member 25 to tubular member 25 and has a guide member .33 threadably secured on the lower end thereof.

' The upward movement of valve 28 is constrained by an arm 3|, which arm is pivoted on bolt 32 at one end. The bolt 32 passes through a link 33 :p-ivoted on bolt 3 which bolt 3 is secured to cas 35. The arm 3! is mounted upon a link 33 which allows the arm M to move downward about bolt 36 without causing any binding action on the bolt due to the arcuate movement of the arm 3 l. The arm 3! extends outward from'pivot point 32 and has an outstanding pin on one side thereof to which a linkage at is attached at its lower end. The linkag if is attached to a Bourdon tube '42 and.- to the pin to at the upper The BQLlrdon tube lzis of the usual construction and is mounted on a hollow bolt 43, which bolt is similar in construction to bolt 22, as shown in Fig. 5. This enables the Bourdon tube it to be adjusted to various operating positions around bolt 43 so as to give a correct movement to linkage ii upon the expansion of Bourdon tube E2, under pressure.

A pipe M connects the tube 22 with valve chamber of the first discharge side of the pump. This enables the discharge pressure of the pump to be transmitted to the Bourdon tube 2 to operate the linkage 4i, arm 3i and valve 28 to control the flow of air through orifice 2?, which operation will be explained more fully hereinafter. A pipe it leads from air reservoir l!) to a diaphragm control valve ti which is posi tioned within motivating fluid line id, which valve ii is controlled in accordance with the pressure within the chamber l9.

The air inlet i8 preferably has a filtering material therein to filter the air of foreign particles before it enters the air system.

In the operation of the control mechanism, the pump 5 is connected to an air, gas or steam pressure line ts in which a valve 4'. is positioned intermediate the pressure'supply and the power end of the pump i. The valve linkage is operated by a connecting-rod 5 upon operation of the lever 6, which lever B is mounted on shaft 1. Aiiixed to the shaft '3 is an arm 8 which arm 8 is bifurcated to receive the outer end of piston rod 9. The piston rod 9 is adapted to operate a plunger type air pump within the cylinder [2.

The air pump is of the type employing inlet valves it and outlet valves It, which outlet valves discharge air pressure into a reservoir 8. The volume of air which the pump l2 delivers depends upon the speed of the bifurcated arm 3 and the linear travel of the piston it. The valve il, is of the character known as a diaphragmvalve and is of the direct acting type, that is, as pressure is applied to the diaphragm in the valve es the valve would tend to close, which in turn would reduce the amount of pressure motivating fluid to the valve chamber and the power end of the pump, therefore, thepump would be slowed. This slowing of the pump would slow the auxiliary air compressor unit which comprises arm 8, piston rod 9 and piston Ill, which in turn, would reduce. the air supply to the reservoir i8.

I A bleeder valve is provided and connects with reservoir is, which bleeder valve is normally open, and if additional air is not pumped into the reservoir E9, the pressure will drop. A nut 37: is provided for adjustment on threadedrod 36 to give a maximum opening of the valve 28. This valve 28 is regulated to bleed off air so as to give the maximum desired operating speed to the pump. With this valve open, if pressure is built up, it will be gradually bled out through valve-28 so as to normalize said pressure, when this pressure is reduced sufiiciently, the valve i? opens and causes the pump i to operate. An arm 3! is positioned above valve 28 and is adapted to be closed thereby upon downward movement of the link ii, one end of which is connected to arm 31 by pints and the other end of which is connected toBourdon tube '22. The Bourdon tube 32 being sensitive to pressure, expands, and causes the closing of the valve due tothe downward movement of the parts as-described. V

The ,Bourdon tube is connected, through; pipe 44, to the fluid head of pump l, which makes the Bourdon tube 42 responsive to the discharge pressure of the pump.

As long as the pump is running at normal speeds, the spring 38 will hold arm 3! in raised position. This will permit the air pressure within reservoir is to lift valve 28 to permit the escape of air therefrom; this will cause a lowering of pressure in the reservoir, the system and the upper surface of the diaphragm which will permit the opening of valve 41 to cause motivating fluid to be directed to the power end of the pump I. If the pump gains in speed, the pressure of the fluid discharge of the pump will normally increase and in so doing the pressure will be transmitted through pipe 44 to Bourdon tube c2 to draw link 4! downward. The arm 3!, which is connected to the link 4|, is also drawn downward into contact with valve 23 to close said valve and prevent the escape of too much air from reservoir l9. With the escape or" air from reservoir l9. reduced or shut off, the pressure on valve 41 willv be built up, which will tend to close the valve 4'! and thus reduce the speed of the pump.

The adjustment of the amount of pressure required to pull the arm 3! downward is taken care of by nut 35, on bolt 35. The nut 39 may be screwed up or unscrewed to increase or decrease the tension on spring 38, which spring is in contact with the lower end of the arm. When the tension on the spring 38 is increased the tendency of the arm to move upward is increased. thus the amount of pressure required to move it down is increased. Conversely. with less tension on spring 36, less pressure will be reouired to move are 3! downward to close valve 28. Thus by the adistment of the nut El, 2. maximum speed of the pump may be maintained regardless of the pressure output side of the pump, and by the adjustment of the nuts 3! and t9 the pump may be set to generate a discharge and a maximum operating speed, independently of each other. Therefore. if the pump should run out of fluid to pump, it will operate at the set speed without tearing itself to pieces, as would have been the case heretofore because the speed of the pump would have increased. Furthermore, if the pump is set at a given operating pressure, it will operate at any speed up to the maximum speed while still maintaining the given pressure.

It is to be pointed out that the device is auxiliary to the pump and is arranged to create its own air supply, and therefore may be attached to any pump that has a motivating fluid line.

Having thus described the invention, I claim:

1. In a fluid pressure regulator, the combination with a fluid supply apparatus havins a fluid actuated fluid supply valve for controlling the supply of motivating fluid in a fluid inlet line, of a fluid pressure generating apparatus having a conduit interconnecting said fluid pressure generating apparatus and said motivating fluid supply valve for actuating said fluid supply valve, means for maintaining a maximum gauged opening of a valve for regulating the pressure on said fluid pressure generating apparatus so as to govern the maximum operating speed of said fluid supply apparatus, pressure means operated by the discharge pressure of said fluid supply apparatus for regulating the minimum speed thereof.

2. In a fluid pressure regulator, the combination with a, fluid supply apparatus having a fluid actuated supply valve for controlling the supply of motivating fluid into said fluid supply apparatus, of a fluid pressure generating apparatus having a conduit interconnecting said fluid pressure generating apparatus and said motivating fluid supply valve for actuating said fluid supply valve, means comprising a threaded member for regulating the maximum opening of a valve for regulating the outlet of fluid from the fluid pressure generating system, a .further control apparatus for said valve comprising a pressure responsive element actuated by the pressure of the discharge of said fluid suppl apparatus so as to further control the speed of the fluid supply apparatus so as to maintain a substantially uniform pressure on the discharge side of said fluid supply apparatus.

3. In a controller for a fluid pressure operated pump, an air pump adapted to be operated in timed relation to the movement of a member of said fluid pressure operated pump, an air chamber connected with said air pump in. which a pressure is adapted to be maintained, a passage interconnecting said air chamber with atmospheric pressure, an orifice within said passage,

means for limiting the maximum opening of said orifice, a valve to close said orifice by a pressure exerted upon a pressure responsive element interconnected with the discharge side of the fluid pressure operated pump, a resilient member adapted to hold valve closing means in an open position, means for adjusting tension on said resilient member so as to vary the effective maximum discharge of said pressure operated pump.

4. In a controller for a fluid pressure operated pump, an air pump adapted to be operated in.

timed relation to the movement of a member of said fluid pressure operated pump, an air cham ber connected with said air pump in which a pressure is adapted to be maintained, a passage interconnecting said air chamber with atmospheric pressure, an orifice within said passage, means for limiting the maximum opening of said orifice, a valve to close said orifice by a pressure exerted upon a pressure responsive element interconnected with the discharge side of the fluid pressure operated pump, a resilient member adapted to hold valve closing means in an open position, means for adjusting tension on said resilient member so as to var th effective maximum discharge of said pressure operated pump, means for adjusting the pressure responsive valve actuating element so as to cause said element to engage valve closing means at different relative positions.

5. In a pressure regulating system for stroke pumps and the like, an air pump actuated in timed relation by the reciprocation of the stroke pump, said air pump being adapted to maintain a pressure in a reservoir in accordance with the volumetric output of said air pump operating at a timed speed and with a gauged outlet therefor, means for controlling the air outlet to atmos phere from the reservoir including an orifice in communication with said reservoir, a valve positioned within said orifice which orifice is adapted to be closed thereby when the valve is in one position and to permit the escape of air from said reservoir when said valve is in another position, adjustable means for regulating the maximum opening of said valve, resilient means adapted to normally hold a valve operating means in one position, means for adjustifigfiaid resilient means, valve closing means adapted to move said valve from open position to closed position in. PIOPOI?! tion to the pressure generated by said .nsideof -said stroke pump andtransmitted to a pressure responsive element connected to thedischarge side of said stroke pump.

6. In an apparatus for regulating the stroke speed and thepressure output of a stroke pump,

an air pump operated by, the stroke of said stroke pump .and in, timed relation thereto, said, air pump being adapted to pump air into a reservoir upon operation of said stroke pump, saideair pump being of. such capacityas to pump a constant supply of air into said reservoir, valve .means havin amaximum set opening for bleeding a maximum predetermined amount of air from said reservoir to atmosphere, a fluid line connecting said reservoir and the diaphragm chamber of a valve, which valve is positioned within a motivating fluid supply line leadingto said pump, saidldiaphragm valve to be operated in accordance with the back pressure on the diaphragm thereof to control the supply of motivating fluid to said stroke pump, an armladapted ,to close said bleeder valve in response to a pressureresponsive element connectedto the discharge side of said pump, a spring adapted to hold saidarm in position to permit said valve to. open under the air pressure escaping from said reservoir, means for adjusting said spring, a linkagearrangement adapted to move the arm in one direction but being free to move in the opposite direction without engagement with said arm.

7.- A pump control comprising a motor-for driving the pump, a pressure generating system operated by said pump, means for controlling the speed of said motor by pressure from said pressure generating system, and means responsive to pressure developed-by said pump for controlling said speed controlling means to maintain the pressure developed by said pump below a predetermined maximum.

8. A pump-control comprising a motor for driving said pump, a pressure generating system ;operated by said pump, means for controlling the speed of said motor by pressure from said pressure generating system, and means responsivetothe speed of said pump for controlling means to maintain, the speed of the. pump. below a, predetermined maximum.

9. A pump control comprising a pump, a fluid motor vfor driving said-pump, a valve for controlling motive fluid to said motor, a pressure generating system driven by said pump, means for operating saidvalve by pressure from said pressure generating system, and means responsive to pressure developed by said pump forcontrolling saidlast named means to maintain the pressure developed by said pump belowa predetermined maximum.

10. A pump control comprising a pump, a fluid motor for driving said pump, a valve forcontrolling motive fluid to said motor, a pressure generating system driven by said pump, means for operating said valve by pressure from said pressure generating system and meansresponsive to the speed of said pump for controlling REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS- Number Name Date 1,999,977 Fournia June 16, 1914 2,009,001 Peterson July 23, 1935 2,276,794 Ricci Mar. '17, 1942