Regulating system for pumps

• US 3,891,354 A
• Filed: 06/11/1974
• Issued: 06/24/1975
• Est. Priority Date: 06/22/1973
• Status: Expired due to Term

• Current Assignee: Paul Bosch
• Original Assignee: Paul Bosch
• Inventors: Bosch, Paul
• Primary Examiner(s): Freeh, William L.
• Assistant Examiner(s): LaPointe, G. P.
• Application Number:
  US05/478,392
• Time in Patent Office: 378 Days
• Field of Search: 417/212,216,218,222 60/449,451
• US Class Current: 417/216
• CPC Class Codes: F04B 1/07 by varying the relative eccentricity between two members, e.g. a cam and a drive shaft
• CPC Class Codes: F04B 2201/0805 Rotational speed of a rotating cylinder block
• CPC Class Codes: F04B 2201/1213 Eccentricity of an outer annular cam
• CPC Class Codes: F04B 2207/04 Settings
• CPC Class Codes: F04B 49/007 Installations or systems with two or more pumps or pump cylinders, wherein the flow-path through the stages can be changed, e.g. from series to parallel centrifugal pumps F04D15/0072
• CPC Class Codes: F04B 49/06 Control using electricity regulating by means of floats actuating electric switches F04B49/04
• CPC Class Codes: F04B 49/08 Regulating by delivery pressure
• CPC Class Codes: F04B 49/103 Responsive to speed
• CPC Class Codes: F04B 49/128 by changing the eccentricity of the cylinders, e.g. by moving a cylinder block

Abstract

A motor, such as an internal combustion engine or an electric motor, drives two or more pumps, which pump fluid through a discharge system, and a speed measuring device is provided for producing a signal when the speed of the motor is reduced due to the load on the motor reaching a predetermined high value, short of an overload. Two or more pump discharge regulators are provided, one for each pump, cooperating with the measuring device to reduce the output of at least one of the pumps in response to a signal to thereby prevent overloading of the engine or motor.

Claims

1. In a pump system wherein at least two pumps are coupled to a single drive motor for pumping fluid under pressure through a discharge system, a regulating arrangement for preventing overloading and stalling of the drive motor, said regulating arrangement comprising at least two displacement control regulating means, one for each pump, and each having control slide means having a first and a second surface adapted to be subjected to the fluid pressure in the discharge system for moving the respective displacement control regulating means to thereby regulate the amount of fluid pumped by the respective pump;

signalling means cooperating with said drive motor for producing a signal in response to a predetermined high load on the motor; and

means for subjecting said first surface to the fluid pressure in the discharge system in response to one of said signals so as to move the control slide means of at least one of said pumps to thereby reduce the amount of fluid delivered by said at least one pump.

2. The regulating arrangement as defined in claim 1, wherein said signalling means comprises a speedometer producing a signal when the number of revolutions per time unit of said drive motor drops below a predetermined minimum.

3. The regulating arrangement as defined in claim 2, wherein said means for subjecting said first surface to said fluid pressure comprises a control valve.

4. The regulating arrangement as defined in claim 1, wherein said discharge system comprises a separate discharge line for each of said pumps, and including selector valve means for selecting the discharge line of that one pump which pumps fluid at the highest pressure and for connecting the discharge line of said one pump to said means for subjecting said first surface to the fluid pressure.

5. The regulating arrangement as defiNed in claim 1, wherein each of said displacement control regulating means comprises a housing formed with a bore, said control slide means comprising a control slide movable in said bore of said housing and being formed with a blind bore extending from one end of said control slide into the latter and having a closed end, and a piston in said blind bore projecting beyond said one end of said control slide and abutting against said housing, said first surface being an annular surface at said one end of said control slide about said piston and said second surface being the surface at said closed end of said blind bore, passage means for normalling subjecting the interior of said blind bore to the fluid pressure in the discharge system to thereby move said control slide in a first direction and biassing means for moving said control slide in a second direction opposite to said first direction, said control slide being movable from a neutral position in said first direction when the pressure in said discharge system drops below a predetermined pressure to thereby regulate the respective pump to increase the amount of fluid pumped thereby, and said control slide moving in said second direction upon subjecting said first surface to said fluid pressure to thereby regulate the respective pump to decrease the amount of fluid pumped thereby.

6. The regulating arrangement as defined in claim 5, wherein each of said pumps comprises adjusting means for regulating the amount of fluid delivered by the respective pump, said adjusting means comprising an adjusting member movable in one direction for increasing the amount of fluid delivered by said pump and in the opposite direction for decreasing the amount and a pair of cylinder and piston means for moving said adjusting member in the one and in the opposite direction, and including passage means for supplying fluid to said cylinder and piston means for moving said adjusting member in said one direction when said control slide is moved from said neutral position in said first direction and for moving said adjusting member in said opposite direction when said control slide is moved from said neutral position in said second direction.

7. The regulating arrangement as defined in claim 3, wherein said signalling means produces an electric signal and wherein said pilot valve comprises a solenoid valve.

8. The regulating arrangement as defined in claim 7, wherein said discharge system comprises a separate discharge line for each of said pumps, and including selector valve means for selecting the discharge line of that one pump which pumps fluid at the highest pressure and first conduit means connecting said selector valve means to said solenoid valve, said solenoid valve being normally in a closed position and being moved from said closed to an open position upon receiving a signal from said signalling means and further conduit means to direct fluid from said first conduit means to said first surfaces of said regulating means in said open position of said solenoid valve.