Method and control device for operating a reciprocating piston pump

Patent metadata

Field	Value
Publication number	US-10738775-B2
Application number	US-201815870660-A
Country	US
Kind code	B2
Filing date	Jan 12, 2018
Priority date	Jan 13, 2017
Publication date	Aug 11, 2020
Grant date	Aug 11, 2020

Abstract

A method for actuating a pump having a reciprocating piston or a diaphragm for pressure generation in a hydraulic system, the reciprocating piston or the diaphragm being moved by way of an actuator which is driven by a magnetic field of a magnet coil, and a system pressure in the hydraulic system being determined.

First claim

The invention claimed is:

1. A method for actuating a pump having a reciprocating piston or a diaphragm for pressure generation in a hydraulic system, the reciprocating piston or the diaphragm being moved by way of an actuator which is driven by a magnetic field of a magnet coil, the method comprising:
determining a system pressure in the hydraulic system; and
operating the magnet coil by selecting between a switch-off by way of freewheeling or a switch-off by way of rapid extinguishing, the selection being dependent on a first pressure curve corresponding to the system pressure and/or to at least one temporally filtered system pressure.

2. The method according to claim 1 , characterized in that the magnet coil is operated with the switch-off by way of freewheeling when the first pressure curve ( 12 ) corresponding to the system pressure lies below a first pressure threshold ( 14 ), and the first pressure curve ( 12 ) or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies above a second pressure threshold ( 15 ), the second pressure threshold ( 15 ) being lower than the first pressure threshold ( 14 ).

3. The method according to claim 1 , characterized in that the magnet coil is operated with the switch-off by way of freewheeling when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and the first pressure curve ( 12 ) or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies below a second pressure threshold ( 15 ) and above a third pressure threshold ( 16 ), and an immediately preceding switch-off took place by way of rapid extinguishing, and with the third pressure threshold ( 16 ) lying below the second pressure threshold ( 15 ).

4. The method according to claim 1 , characterized in that the magnet coil is operated with the switch-off by way of rapid extinguishing when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and the first pressure curve ( 12 ) or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies below a third pressure threshold ( 16 ).

5. The method according to claim 1 , characterized in that the magnet coil is operated with the switch-off by way of rapid extinguishing when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies below a second pressure threshold ( 15 ) and above a third pressure threshold ( 16 ), and an immediately preceding switch-off took place by way of freewheeling.

6. A control device, the control device comprising a program sequence or a circuit for carrying out the method according to claim 1 .

7. The method according to claim 1 , wherein the pump is free from a regulating valve.

8. A method for actuating a pump having a reciprocating piston or a diaphragm for pressure generation in a hydraulic system, the reciprocating piston or the diaphragm being moved by way of an actuator which is driven by a magnetic field of a magnet coil, the method comprising:
determining a system pressure in the hydraulic system; and
operating the magnet coil with a switch-off by way of freewheeling or a switch-off by way of rapid extinguishing in a manner which is dependent on the basis of an evaluation of a time gradient of a first and/or a second pressure curve.

9. The method according to claim 8 , wherein the pump is free from a regulating valve.

10. A method for actuating a pump having a reciprocating piston or a diaphragm for pressure generation in a metering device of a urea/water solution in a nitrogen removal system, the reciprocating piston or the diaphragm being moved by way of an actuator which is driven by a magnetic field of a magnet coil, the method comprising:
determining a system pressure in the metering device; and
operating the magnet coil by selecting between a switch-off by way of freewheeling or a switch-off by way of rapid extinguishing in a manner which is, the selection being dependent on a first pressure curve corresponding to the system pressure and/or at least one temporally filtered system pressure.

11. The method according to claim 10 , wherein the magnet coil is operated with the switch-off by way of freewheeling when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and the first pressure curve ( 12 ) or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies above a second pressure threshold ( 15 ), the second pressure threshold ( 15 ) being lower than the first pressure threshold ( 14 ).

12. The method according to claim 10 , wherein the magnet coil is operated with the switch-off by way of freewheeling when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and the first pressure curve ( 12 ) or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies below a second pressure threshold ( 15 ) and above a third pressure threshold ( 16 ), and an immediately preceding switch-off took place by way of rapid extinguishing, and with the third pressure threshold ( 16 ) lying below the second pressure threshold ( 15 ).

13. The method according to claim 10 , wherein the magnet coil is operated with the switch-off by way of rapid extinguishing when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and the first pressure curve ( 12 ) or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies below a third pressure threshold ( 16 ).

14. The method according to claim 10 , wherein the magnet coil is operated with the switch-off by way of rapid extinguishing when the first pressure curve ( 12 ) lies below a first pressure threshold ( 14 ), and a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation lies below a second pressure threshold ( 15 ) and above a third pressure threshold ( 16 ), and an immediately preceding switch-off took place by way of freewheeling.

15. The method according to claim 10 , wherein a decision about a switch-off of the magnet coil by way of freewheeling or by way of rapid extinguishing takes place solely or additionally on the basis of an evaluation of a time gradient of the first pressure curve ( 12 ) and/or a second pressure curve ( 13 ) derived from the temporally filtered system pressure by a low pass filtering operation.

16. A control device, the control device comprising a program sequence or a circuit for carrying out the method according to claim 1 .

17. The method according to claim 10 , wherein the nitrogen removal system is provided for an exhaust gas channel of an internal combustion engine.

18. The method according to claim 10 , wherein the pump is free from a regulating valve.

Assignees

• Bosch Gmbh Robert

Inventors

• Boos Edna
• Waschler Roland

Classifications

• F04B49/065

  and making use of computers · CPC title

• F04B49/022

  by means of pressure · CPC title

• F04B17/04 Primary

  using solenoids · CPC title

• F04B43/04 Primary

  Pumps having electric drive · CPC title

• F04B2205/06

  Pressure in a (hydraulic) circuit · CPC title