Method and system for noise control in hydraulic pumps

Abstract

A method for attenuating hydraulic pump flow pulses is described. The method includes pumping a fluid at a first hydraulic flow rate to an operating device via the pump, the flow being in the form of discrete fluid pulses. Further, the method includes obtaining values of plurality of parameters related to the pulses produced by the pump and attenuating the pulses by modifying the first hydraulic flow rate to a second hydraulic flow rate based on the obtained values.

1 . A method for attenuating flow pulses originating from a hydraulic pump, the method comprising:
 pumping a fluid at a first hydraulic flow rate to an operating device via the pump, wherein the flow includes discrete pulses of fluid;   obtaining values of one or more parameters related to the pulses produced by the pump; and   attenuating the pulses produced by the pump by modifying the first hydraulic flow rate to a second hydraulic flow rate based on the obtained values, wherein the second hydraulic flow cancels the pulses produced by the first hydraulic flow.   
     
     
         2 . The method of  claim 1 , wherein the parameters include one or more of:
 frequency;   phase; or   amplitude.   
     
     
         3 . The method of  claim 2 , wherein the value of the frequency is obtained based on engine speed of the operating device. 
     
     
         4 . The method of  claim 2 , wherein the value of the frequency is obtained based on the pump order. 
     
     
         5 . The method of  claim 2 , wherein the value of the frequency is based on ratio of the engine crankshaft pulley diameter to the pump pulley diameter. 
     
     
         6 . The method of  claim 1 , wherein the obtaining step further includes transmitting the obtained values to an electronic control unit (ECU). 
     
     
         7 . The method of  claim 1 , wherein the attenuating step further includes setting the second hydraulic flow rate as out of phase with the first hydraulic flow rate. 
     
     
         8 . The method of  claim 1 , wherein the attenuating step is performed by the ECU. 
     
     
         9 . The method of  claim 1 , wherein the pump is a hydraulic steering pump used in an automotive steering system. 
     
     
         10 . A hydraulic pump flow system comprising:
 a hydraulic pump configured to pump fluid in form of discrete pulses to an operating device at a first hydraulic flow rate;   a monitoring module configured to obtain values of one or more parameters related to the pulses produced by the pump; and   an electronic control unit (ECU) configured to attenuate the pulses produced by the pump by modifying the first hydraulic flow rate to a second hydraulic flow rate based on the obtained values, wherein the second hydraulic flow cancels the pulses produced by the first hydraulic flow.   
     
     
         11 . The system of  claim 10 , wherein the parameters include one or more of:
 frequency;   phase; or   amplitude.   
     
     
         12 . The system of  claim 11 , wherein the value of the frequency is obtained based on engine speed of the operating device. 
     
     
         13 . The system of  claim 11 , wherein the value of the frequency is obtained based on the pump order. 
     
     
         14 . The system of  claim 11 , wherein the value of the frequency is obtained based on ratio of the engine crankshaft pulley diameter to the pump pulley diameter. 
     
     
         15 . The system of  claim 10 , wherein the monitoring module includes a transducer. 
     
     
         16 . The system of  claim 10 , wherein the monitoring module transmits the obtained values to the ECU. 
     
     
         17 . The system of  claim 10 , wherein the ECU sets the second hydraulic flow rate as out of phase with the first hydraulic flow rate. 
     
     
         18 . The system of  claim 10 , wherein the pump is a hydraulic steering pump used in an automotive steering system. 
     
     
         19 . A method for reducing vibrations due to steering pump flow in a vehicle, the method comprising:
 pumping fluid at a first hydraulic flow rate to a steering valve via the pump, wherein the fluid is in the form of discrete pulses;   obtaining values of one or more parameters related to the pulses produced by the pump;   calculating a second hydraulic flow rate based on the obtained values; and   reducing the vibrations by modifying the first hydraulic flow rate to the second hydraulic flow rate, wherein the second hydraulic flow rate is out of phase with the first hydraulic flow rate.   
     
     
         20 . The method of  claim 19 , wherein the parameters include one or more of:
 frequency;   pressure; or   amplitude.