US2900918A - Electrically operated transfer valve for centrifugal pump - Google Patents

Description

Aug. 25, 1959 D. F. THOMAS ETAL 2,900,918 ELECTRICALLY OPERATED TRANSFER VALVE FOR CENTRIFUGAL PUMP Filed June 4 1956 5 Sheets-Sheet 1 (91 T T W C90\ 91 90 7 l 619 9/? 6y F I1. 76 a u] l {\VENTQR FIG 4 Dar/d F 7770mm:

BY 95W UREA/1% Aug. 25, 1959 D. F. THOMAS ETAL 2,900,918

ELECTRICALLY OPERATED TRANSFER VALVE FOR CENTRIFUGAL PUMP Dar/a 1? Thomas Haber) A. /7/'// ATTORNEY Aug. 25, 1959 D. F. THOMAS ET AL 2,900,918

ELECTRICALLY OPERATED TRANSFER VALVE FOR CENTRIFUGAL PUMP v Filed June 4. 1956 3 Sheets-Sheet 3 IN VENTOR Dar/a 1? 7710mm Faber) 14. 1917/ BY (26W 25 ATTORNEY United States Patent ELECTRICALLY OPERATED TRANSFER VALVE FOR 'CENTRIFUGAL PUlVIP David F. Thomas, West St. Paul, and Robert A. Hill, Minneapolis, Minn., assignors to Waterous Company, St. Paul, Minn., a corporation of Minnesota Application June 4, 1956, Serial No. 589,320

9 Claims. (Cl. 103-106) This invention relates to an improvement in electric power operated transfer valves and deals particularly with a means of actuating a transfer valve in a parallel or series operated centrifugal pump.

Centrifugal pumps of the type used on fire-fighting equipment and the like often employ two or more stages. Each stage has its own inlet and discharge. Passengers are provided in the pump housing for connecting the discharge passages of each individual stage to a discharge manifold for the pump. A passage is also provided connecting the discharge passage of a first stage to the intake passage of a second stage. A transfer valve is provided in the discharge passage of the first stage so that liquid may be directed either to the discharge manifold of the pump or to the intake manifold of the second stage.

While these transfer valves have been used successfully for a considerable period of time, they are usually manually operated. Linkage is usually provided to connect the operating arm of the valve to a point readily accessible to the pump operator. By manually moving this linkage the position of the valve may be changed. However, in certain instances, the linkage is difiicult to operate and the position of the valve must be noted from'the position of the operating linkage. If, for example, the linkage is not in proper adjustment or if the linkage is not moved to its extreme position, the efficiency of the pump may be reduced.- Furthermore, considerable force is often required to shift the valve due to friction upon the various parts of the linkage. It is an object of the present invention to eliminate these previous difficulties. 1 e

- Attempts have been made to apply a pneumatically operated means for shifting the valve. Power for actuating the-valve operating mechanism has been takenfrom the intake manifold of the internal combustion engine operating the pump. In other words, air on one side of a cylinder is partially evacuated so that" atmospheric pressure will operate the valve actuating mechanism to another extreme position. Thisarrangement has the disadvantage that the supply of partial vacuum varies when the engine is subjected to diiferent'loads.

An object of the present invention lies in correcting thisprevious difficulty. J p

A feature of the present invention resides in the provisioriof electrically operated means for actuating the transfer valve; Means are provided for operating the valve electrically between predetermined fixed. limits to insure the proper placement of the valve in either position.

A further feature of the present invention resides in theprovision of a transfer valve actuating means which functions automatically to move the valve a predetermined angular distance and then to stop the operating device. The operating switch may accordingly remain idoneposition until after the valve actuatingmechanism has completed the movement of the valve. 3 y

I An added feature of the present invention residesin the provision of indicator means which indicate the 10- "ice cation of the valve to the operator. This indicator functions to disclose to the operator at all times the position of the valve.

These and other objects and novel features of the present invention will be more clearly and fully described in the following specification and claims:

In the drawings forming a part of the specification:

Figure 1 shows a plan view of a centrifugal pump showing the transfer valve and valve actuating mechanism attached thereto.

Figure 2 is a diagrammatic view showing the position of the transfer valve when the impellers are connected in parallel.

Figure 3 is a view similar to Figure 2 showing the position of the transfer valve when the impellers are connected in series.

Figure 4 is a diagrammatic view showing the wiring diagram of the apparatus.

Figure 5 is a plan view of the transfer valve operating mechanism on a larger scale.

Figure 6 is an elevation view, partly in section, showing the transfer valve operating mechanism.

The pump A comprises a centrifugal pump of the type commonly used on fire fighting equipment. The pump A includes a main housing 10 which is preferably split along a horizontal plane to permit the impellers and impeller shaft to be properly housed. The ends of the housing 10 are flanged as indicated at 11 and 12. An intake manifold 13 and manifold extension 14 are attached to the flange 11 and a somewhat similar intake manifold 15 and manifold extension 16 are attached to the flange 12. y A

A discharge manifold 17 is also connected to the flange 11 by suitable fastening meansand a somewhat similar discharge manifold 19 is connected to the flange 12. The discharge manifold 17 is branched to accommodate manifold extensions 20 and 21 incorporating discharge valves 22 and 23. The manifold 19 is similarly branched and one of the branches is provided with an extension 25 incorporating a discharge valve 26. The other branch of the manifiold 19 is connected by a by-pass adapter2 7 to the relief valve 29, which is connected to the intake manifold extension 16. i

In order that the flow of fiuid through the pump may be understood, the diagrams of Figures 2 and 3 have been presented. The housing 10 is shown as including a first impeller chamber 30 and a second impeller chamber 31 enclosing first and second impellers 32 and 33, respectively. The impellers 32 and 33 are mounted upon a shaft 34 which is shown in Figure 1 as extending from the housing into a gear case 35 containing suitable drive gears. driven by a suitable drive shaft 36 connected to the internal combusion engine of the fire truck or to another suitable source of power.

The impeller chamber 30 is connected by a passage 37 to a transfer valve 39 which controls the direction of flow of the fluid pumped from the impellerchamber 30. The valve39 includes a valve passage 40 which is shown in Figure 2 as providing a connection between;

The intake manifolds 13 and 15 are connected to the annular intake 44 of the impeller 32 and also to the an- The gears within the gear case 35 are.

3 nular intake 45 or the impeller 33. Flap valves 46 and 47 are provided in the branches of the intake manifolds 13 and 15 to close these branches in the event the intake of the second impeller 33 is subject to higher pressures than the remainder of the intake manifolds.

Figure 3 shows the position of the 'various elements when the impellers are connected in series. It will be noted that in this position the transfer valve 39 is located so that its passage 40 communicates with a passage 49 leading to the intake 45 of the impeller 33. In this position the first stage impeller chamber communicates with the intake of the impeller 33 subjecting the intake to increased pressure. The valves 46 and 47 are closed by this increased pressure. Thus all of the fluid is directed through the discharge passage 43 of the second stage impeller 33 to the discharge manifolds.

While the description of the pump has been purposely brief, it is believed sufiicient to disclose the type of operation achieved by' the pump and to show the position of the transfer valve 39.

The transfer valve 39 is mounted within a cylindrical I bronze bushing which fits within a bore in the housing 10,

thebushing forming a transfer valve housing. The valve 39 is provided with an axially extending operating shaft 50. This shaft 50 extends through the top closure plate of the valve compartment and is equipped with a radially extending operating arm 52. An electrically operated expandable and contractable actuator 53 is pivotally connected at 54 to the arm 52 and is pivotally connected at 55 to a fixed bracket 56 mounted to overlie the transfer valve closure plate. Operation of the actuator 53 rotates the arm 52 through an angular distance sufficient to move the transfer valve between the extreme positions shown in Figures 2 and 3.

The details of the actuator will be later described. However, the actuator includes a motor 57 which acts to rotate a vertical shaft supporting a worm 58 which in rotates a worm gear 58' fixed to a threaded rod extending longitudinally of the actuator. This, in turn, rotates'in a fixed nut which is fastened to the actuator arm 59 to move the arm 59 from the contracted position shown in Figure 1 to an expanded position. This, in turn, rotates the shaft 50 and the valve 39.

Figure 4 of the drawings shows the control circuit for controlling the operation of the motor 57 and also the indicator circuits. As is indicated, the motor 57 is ener- Igized by a source of power 60 which is usually the vehicle battery having a grounded terminal 61. The other battery terminal is connected by a conductor 62 leadingthrough a circuit breaker 63 to a common conductor 64. The common conductor 64 extends into a relay 65 and is connected to one terminal of a pair of relay coils 66 and 67. The other terminal of the coil 66 is connected by a conductor 69 to a normally closed contact 70 of a microswitch 71. The blade 100 of the micro-switch 71 is con nected by aconductor 72 to a switch terminal 73 on a control panel 74. The contact 73 is engageable with a switch arm 75 which is grounded at 76.

The micro-switch 71 also includes a normally open contact 77 connected by a conductor 79 to one terminal of anindicator light 80 (usually green), the other terminal of which is connected by conductor 81 to the common conductor 64.

The second terminal of the relay coil 67 is connected by conductor 82 to a normally closed switch terminal 83 which is normally in contact with the switch blade 84 of the micro-switch 85. The switch blade 84 is connected by conductor 86 to a switch terminal 87 selectively engageable with the grounded switch arm 75. The microswitch 85 also includes a normally open terminal 89 connected by a conductor 90 to an indicator light 91 (usually amber), the other terminal of which is connected by conductor 81 to the common power conductor'64.

The relay coil 66 controls a relay armature 92 connected to common power conductor 64 and engageable with 'a relay contact 93 when the coil 66 is energized. The terminal 93 is connected by a conductor 94 to the motor 57 which is of a reversible type. When the relay coil 66 is energized, the motor 57 is operated in one direction.

The relay coil 67 controls the operation of a relay armature 95 which is connected to the power conductor 64 and which is engageable with a relay contact 96 when the coil 67 is energized. A conductor 97 connects the terminal 96 to the motor 57 having a grounded terminal at" 99. Energization of the relay coil 67 thus closes a circuit from the common power conductor to the motor 57 to rotate this motor in a reverse direction.

The operation of the control is as follows:

When the switch arm 75 is in a neutral or open position, the circuits to the motor 57 as well as to the indicator lights 80 and 91 are broken. If the arm 75 is moved to the left into contact with the contact 73 and if the valve arm 52 is in position for parallel operation of thepu-mp, the motor 57 will not be energized but a circuit will be closed from the grounded switch arm 75 through contact 73, conductor 72, micro-switch blade 100, normally open contact 77 and conductor 79 to one terminal of the indicator light 80. If the other terminal of. this light is connected to the common power conductor 64 through conductor 81, the indicator light 80 Will be illuminated to. show that the valve is in position for parallel op eration.

In the event series operation of the pump is desired, the switch arm 75 is moved into contact with contact 87 which is connected by conductor 86 to the micro-switch blade 84. This blade is in contact with the normallyclosed contact 83 connected by conductor 82 to the coil 67, the other terminal of which is connected to conductor 64. As a result the coil 67 is energized drawing the armature 95 against the contact 96 and closing a circuit from the power conductor 64 through conductor 97 to the motor 57. The motor 57 is energized to move the valve arm 52 to its other extreme position.

When the arm 52 disengages the micro-switch blade 100 from the normally open contact 77, thus breaking the cir-' cuit to the indicator light 80, the blade 100 engages the normally closed contact 70 of the micro-switch 71 but as this circuit is broken between the contact 73 and the switch arm 75 no additional circuit is energized.

When the. valve arm 52 reaches its opposite extreme position,.the micro-switch blade 84 is disengaged from the normally closed contact 83 opening the circuit to the relay coil 67 and permitting the armature 95 to move into open position. This breaks the circuit to the motor 57. Simultaneously, the micro-switch blade 84 engages the normally open contact 89 forming a circuit from the grounded switch arm 75 through contact 87, conductor 86, switch blade 84, contact 89, and conductor leading to the indicator light 91. As the other terminal of the indicator light 91 is connected to the common power conductor 64 through the conductor 81, the light 91 will be illuminated to show that the valve 39 is in position for series operation. 7 When the operator desires to return the pump to parallel operation, a similar operation is produced. The switch arm 75 is moved into contact with the contact 73 thus breaking connection with contact 87 and breaking the circuit through conductor 86, switch blade 84, normally open contact 89, and conductor 90 to the indicator light 91. A circuit is closed from the grounded switch arm 75' through contact 73, conductor 72, switch blade 100, normally closed contact 70 and conductor 69 to one terminal of the relay coil 66, the other terminal of which the micro-switch 71 opening the motor circuit and simultaneously closing the circuit to indicator light 80 previously described. Thus it will be seen that the transfer valve will operate between fixed limits by merely moving the switch arm 75 to a selected position. The indicator lights also indicate the position of the transfer valve when it is in either extreme position unless the switch arm 75 is moved to a neutral position. At this time the circuits will all be broken.

With reference now to Figures and 6 of the drawings, it will be noted that the actuator includes an elongated tubul-ar cover 104 having a bearing 105 therein designed to slidably support the actuator arm 59. The arm 59 is shown as tubular, and supports a ball bearing nut 106 which is fixed within an end of the arm. A threaded rod 107 is suitably supported by thrust bearings not illustrated, and can rotate within the nut. The rod 107 supports the worm gear 58' in mesh with the worm 58 rotated by the motor 57 as previously described.

As shown in Figure 6, the tubular arm 59 is fitted on its outer end with a bushing 109 having a cylindrical outer surface. A peripheral flange 110 forms a shoulder at one end of the bushing 109. A pivot block 111 encircles the cylindrical bushing surface. The bushing 109 is held from rotation relative to the tubular arm 59 by means of a pin 112 which cannot be removed when the pivot block 111 is in position.

. 6 t ply, said main switch, said normally open switch of said first limit switch, and said first relay coil, a second circuit including said current supply, said main switch, said normally closed switch of said second limit switch, and said second relay coil, a thirdcircuit including said our rent supply, said first indicator means, and said first normally open switch of said first limit switch, a fourth circuit including said power source, said main switch, said normally open switch of said second limit switch, and

said second indicator means, said main switch being operable to selectively close said first and third circuits or said second and fourth circuits, said electrically operable means having forward and reverse operating means, a

. circuit including said power source, said forward operat- The bushing 109 is externally grooved at 113 to accommodate a snap ring114. This ring 114 is designed to exert an axial pressure against the pivot block 111, friction-ally engaging this pivot block with the flange 110. This frictional engagement is suflicient to normally hold the tubular arm 59 from rotation within the pivot block 111. In other words, the frictional engagement between the bushing 109 and pivot block 111 is greater than the frictional engagement between the nut 106 and threaded rod 107, so that the nut 106 and its supporting arm 59 normally remain stationary when the rod 107 is rotated.

The bushing 109 is provided with an inwardly projecting flange 115 at its outer extremity having an axial opening 116 therethrough. A rod 117 is slidably supported in the opening 116 and may be pinned to the bushing by a pin 119. The rod 117 may be provided with a knob or other means to simplify rotation. Rotation of the rod 117 acts to rotate the arm 59 and accordingly the nut 106, thereby permitting movement of the arm relative to the threaded rod 107. By this arrangement, the valve may be manually actuated without disconnect ing the actuator in the event of electrical or mechanical failure of the apparatus.

In accordance with the patent statutes, we have described the principles of construction and operation of our electric power operated transfer valve and while we have endeavored to set forth the best embodiment thereof, we desire to have it understood that changes may be made within the scope of the following claims without departing from the spirit of our invention.

We claim:

1. In combination with a two stage centrifugal pump constructed for parallel or series operation, a valve for controlling the flow of fluid through said pump, a valve shaft connected to, and rotatable with, said am, a reversible electrically operable means for actuating said valve shaft for rotating said valve between predetermined limits, control means for controlling the operation of said electrically operable means, said control including a manually operable main switch, first and second electrically operable indicator means, first and second limit switches operable by said valve upon movement into its opposite extreme positions, each limit switch including a normally closed switch and a normally open switch, first and second relay coils, and first and second relay armatures actuated by said first and second relay coils, the control including a first circuit including a source of current suping means, and said first relay armature, and a circuit including said power source, said reverse operating means, and said second relay armature.

2. In combination with a valve for controlling the flow of fluid, valve operating means connected to said valve to selectively position the valve, and an actuator for actuating said valve operating means, said actuator including a rotatably supported shaft member, an electric motor, means connecting said motor and said shaft member to rotate said shaft member with said motor, a relatively non-rotatable member, a threaded engagement between said shaft member and said relatively nonrotatable member, rotation of said shaft member acting to move said non-rotatable member longitudinally, means supporting said shaft member, means pivotally supporting said support, and means pivotally connecting said relatively nonrotatable member to said valve operating means, whereby operation of said motor may move said transfer valve.

3. The structure described in claim 2 and including two circuits including a power source connected to said motor to rotate the same in each direction, each circuit including a limit switch positioned to break that circuit when the valve reaches a predetermined position.

4. The structure described in claim 2 and in which said non-rotatable member is rotatably supported, means normally holding said non-rotatable member from rotation when said shaft member rotates, and including manually operable means for rotating said non-rotatable member.

5. The structure described in claim 2 and including a bracket secured to said pump adjacent to said valve to which said support is pivoted comprising the means pivotally connecting the support to the pump.

6. In combination with a valve for controlling the flow of fiuid, valve operating means connected to said valve to selectively position the valve, and an actuator including a rotatably supported shaft member, an electric motor, means connecting said motor and said shaft member to rotate said shaft member with said motor, a second shaft member in telescoping relation to said first shaft member, a threaded engagement between said shaft members, supporting means holding said first mentioned shaft member from axial movement, rotation of said first rotatable member by said motor causing axial movement of said second shaft member, means pivotally supporting said supporting means, means rotatably supporting said second shaft member, means pivotally connecting said last named means to said valve operating means, and means normally holding said second shaft member from rotation.

7. The structure described in claim 6 and including means for manually rotating said second shaft member when said first shaft member is stationary.

8. In combination with a rotatable valve having a valve shaft, an elongated bracket plate through which said shaft extends, a valve housing to which said bracket plate is secured, a valve operating arm secured to said shaft to overlie said plate, a pair of limit switches mounted on said plate for engagement with said arm in different angular positions, and an elongated expandable and com 7 tractable element having one end pivotally connected to said bracket, means pivotally connecting the other bracket end tosaid Valve operating arm at a point spaced from the axis .of aid valve shaft, said bracket, limit switches and actuator being detachably connected as a unit to said valve housing.

9. The structure described in claim 8 and includin a reversible electric means forming a part of, and operable to expand and contract said actuator, and two circuits to said electric means each capable of operating the electric means in one direction, each circuit including a power source and one of said limit switches.

References Cited in the file of this patent UNITED STATES PATENTS 828,547 Hayden Aug. 14', 1906 8 Bettinger ..-a.. Mar. 30, 1909 Merrill -s Jan.7, 1913:

Haymond' s Apr. 27, 1915 Jones; June28-,1932 Chandler Feb 21, 1933 Wi1helni Dec. 25 1945 Waterous Dec. 1,1953 Chapman e Feb; 2, 1954 Towle'et a1 1- Mar. 13, 1956 Clinker s Feb. 12, 1957 FOREIGN PATENTS Netherlands Jan. 12, 1919 Switzerland July 1, 1925

Images