Method for operating a device for the dosed supply of a liquid

Patent metadata

Field	Value
Publication number	US-2016108785-A1
Application number	US-201414786363-A
Country	US
Kind code	A1
Filing date	Apr 16, 2014
Priority date	Apr 26, 2013
Publication date	Apr 21, 2016
Grant date	—

Abstract

A method for operating a device configured to provide a dosed supply of a liquid. The device has: a pump delivering the liquid and having a pump housing having an inlet and an outlet, an eccentric on the pump housing, and a deformable diaphragm arranged between the pump housing and the eccentric. The deformable diaphragm and the pump housing delimit a delivery path from the inlet to the outlet and form at least one seal of the delivery path, the seal being displaceable along the delivery path by a movement of the eccentric to deliver the liquid. The method comprises: detecting a demanded dose amount of the liquid; activating the pump to deliver the liquid by the pump; stopping operation of the pump when the delivered amount of the liquid corresponds to the demanded dose amount; deactivating the pump when the eccentric is situated in a predefined park position.

First claim

1 - 10 . (canceled)

11 . A method for operating a device ( 1 ) configured to provide a dosed supply of a liquid, the device ( 1 ) having: at least one pump ( 2 ) configured to deliver the liquid, the at least one pump ( 2 ) having a pump housing ( 3 ) having at least one inlet ( 4 ) and at least one outlet ( 5 ); an eccentric ( 6 ) arranged on the pump housing ( 3 ), and a deformable diaphragm ( 7 ) arranged between the pump housing ( 3 ) and the eccentric ( 6 ), the deformable diaphragm ( 7 ) and the pump housing ( 3 ) delimiting at least one delivery path ( 8 ) from the at least one inlet ( 4 ) to the at least one outlet ( 5 ) and forming at least one seal ( 9 ) of the delivery path, the at least one seal ( 9 ) being displaceable along the delivery path ( 8 ) by a movement of the eccentric ( 6 ) to deliver the liquid, the method comprising:
detecting a demanded dose amount of the liquid; activating the at least one pump ( 2 ) to deliver the liquid by the at least one pump ( 2 ); stopping operation of the at least one pump ( 2 ) when the delivered amount of the liquid corresponds to the demanded dose amount; and deactivating the at least one pump ( 2 ) when the eccentric ( 6 ) is situated in a predefined park position ( 10 ).

12 . The method as claimed in claim 11 , wherein the eccentric ( 6 ) is configured to be in force equilibrium when in the predefined park position ( 10 ).

13 . The method as claimed in claim 11 , wherein, in the predefined park position ( 10 ), the at least one seal ( 9 ) closes off the at least one outlet ( 5 ) of the at least one pump ( 2 ).

14 . The method as claimed in claim 11 , wherein, in the predefined park position ( 10 ), the at least one seal ( 9 ) is arranged downstream of the inlet ( 4 ) of the at least one pump ( 2 ) by a predefined angle ( 41 ) as viewed in the delivery direction ( 27 ).

15 . The method as claimed in claim 11 , wherein the at least one pump ( 2 ) is configured such that the eccentric ( 6 ) passes through the predefined park position ( 10 ) at least once during one complete revolution.

16 . The method as claimed in claim 11 , wherein the at least one outlet ( 5 ) of the at least one pump ( 2 ) is adjoined by a pressure line ( 11 ) leading to an injector ( 12 ) configured to provide dosed dispensing of the liquid, wherein the dispensed amount of liquid is adjustable in accordance with pressure in the pressure line ( 11 ) and an opening time of the injector ( 12 ).

17 . The method as claimed in claim 11 , wherein the at least one outlet ( 5 ) of the at least one pump ( 2 ) is adjoined by a pressure accumulator ( 13 ) and an injector ( 12 ), and the at least one pump ( 2 ) delivers the liquid into the pressure accumulator ( 13 ), wherein the amount of liquid dispensed by the device ( 1 ) is adjustable in accordance with pressure in the pressure accumulator ( 13 ) and an opening time of the injector ( 12 ).

18 . The method as claimed in claim 17 , wherein the pressure accumulator ( 13 ) comprises an elastic pressure line ( 11 ) from the at least one pump ( 2 ) to the injector ( 12 ).

19 . The method as claimed in claim 17 , wherein the at least one pump ( 2 ) has a minimum delivery volume ( 39 ) delivered by the at least one pump ( 2 ) when the eccentric ( 6 ) moves from one predefined park position ( 10 ) into a next predefined park position ( 10 ), and the pressure accumulator ( 13 ) has a maximum pressure accumulator operating volume ( 38 ), by which the volume of the pressure accumulator ( 13 ) changes when the pressure in the pressure accumulator ( 13 ) increases from a minimum operating pressure ( 14 ) to a maximum operating pressure ( 15 ), wherein the maximum pressure accumulator operating volume ( 38 ) is at least equal to the minimum delivery volume ( 39 ).

20 . A motor vehicle ( 17 ) having an internal combustion engine ( 18 ), an exhaust-gas treatment device ( 16 ) configured to purify exhaust gases of the internal combustion engine ( 18 ), and a device ( 1 ) configured to deliver a liquid consisting of urea-water solution to the exhaust-gas treatment device ( 16 ), wherein the device ( 1 ) configured to deliver the liquid is configured to operate in accordance with the method as claimed in claim 11 .

Assignees

• Continental Automotive Gmbh

Inventors

• Brück Rolf
• Hodgson Jan

Classifications

• F01N3/208 Primary

  Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F04C5/00

  Rotary-piston machines or pumps with the working-chamber walls at least partly resiliently deformable (such pumps specially adapted for elastic fluids F04C18/00) · CPC title

• F04C2220/24

  for metering throughflow · CPC title

• F04B43/02

  having plate-like flexible members, e.g. diaphragms (F04B43/14 takes precedence) · CPC title