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

Patent metadata

Field	Value
Publication number	US-9752484-B2
Application number	US-201414786320-A
Country	US
Kind code	B2
Filing date	Apr 16, 2014
Priority date	Apr 26, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A method for operating a device for the dosed supply of a liquid includes: detecting a demanded dose amount of the liquid; activating an electric drive of a pump to move a seal in a delivery direction from an inlet to an outlet to deliver the liquid by application of an operating voltage to the electric drive; stopping operation of the pump when the delivered amount of the liquid corresponds to the demanded dose amount; stopping movement of an eccentric; and maintaining a holding voltage at the electric drive. In response to the holding voltage, a holding torque is exerted on the eccentric and a movement of the eccentric counter to the delivery direction is prevented.

First claim

The invention claimed is:

1. A method for operating a device ( 1 ) having: at least one pump ( 2 ) configured to deliver a 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 ) so as to be rotatable relative to the pump housing ( 3 ); and a deformable diaphragm ( 7 ) arranged between the eccentric ( 6 ) and the pump housing ( 3 ), the deformable diaphragm ( 7 ) and the pump housing ( 3 ) delimiting a 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 ( 8 ), 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 at least one pump ( 2 ) having an electric drive ( 26 ) configured to move the eccentric ( 6 ), the method comprising:
detecting a demanded dose amount of the liquid;
activating the electric drive ( 26 ) of the at least one pump ( 2 ) to move the at least one seal ( 9 ) in a delivery direction ( 27 ) from the inlet ( 4 ) to the outlet ( 5 ) to deliver the liquid by application of an operating voltage ( 10 ) to the electric drive ( 26 );
stopping operation of the at least one pump ( 2 ) when the delivered amount of the liquid corresponds to the demanded dose amount;
stopping movement of the eccentric ( 6 ); and
maintaining a holding voltage ( 35 ) at the electric drive ( 26 ), wherein, in response to the holding voltage ( 25 ), a holding torque ( 38 ) is exerted on the eccentric ( 6 ) and a movement of the eccentric ( 6 ) counter to the delivery direction ( 27 ) is prevented.

2. The method as claimed in claim 1 , wherein a friction torque ( 13 ) assists the exerted holding torque ( 38 ).

3. The method as claimed in claim 1 , wherein the holding voltage ( 35 ) is selected such that the holding torque ( 38 ) lies between a maximum torque and a minimum torque that can be exerted on the eccentric ( 6 ) by the liquid due to a pressure difference between the at least one outlet ( 5 ) and the at least one inlet ( 4 ).

4. The method as claimed in claim 1 , wherein the electric drive ( 26 ) of the pump ( 2 ) has a power consumption of less than 15 watts when the holding voltage ( 35 ) is applied to the electric drive ( 26 ).

5. The method as claimed in claim 1 , wherein the holding voltage ( 35 ) is generated by pulse width modulation ( 15 ).

6. The method as claimed in claim 1 , wherein a position ( 34 ) of the eccentric ( 6 ) relative to the pump housing ( 3 ) is detected before the maintaining, and a maximum possible torque that can be exerted on the eccentric ( 6 ) by the liquid is determined based on the position ( 34 ), and the holding voltage ( 35 ) is set based on the maximum possible torque.

Assignees

• Continental Automotive Gmbh

Inventors

• Brück Rolf
• Hodgson Jan

Classifications

• F04C2/22

  of internal-axis type with equidirectional movement of co-operating members at the points of engagement, or with one of the co-operating members being stationary, the inner member having more teeth or tooth-equivalents than the outer member · 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

• F01N2610/144

  Control thereof · CPC title

• F01N9/00

  Electrical control of exhaust gas treating apparatus (monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00) · CPC title

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title