Electronic pressure relief in pumps

Patent metadata

Field	Value
Publication number	US-2017167340-A1
Application number	US-201514965016-A
Country	US
Kind code	A1
Filing date	Dec 10, 2015
Priority date	Dec 10, 2015
Publication date	Jun 15, 2017
Grant date	—

Abstract

An aftertreatment system comprises a reductant storage tank and a selective catalytic reduction (SCR) system including a catalyst for reducing constituents of an exhaust gas. A reductant insertion assembly including a pump and dosing valve is fluidly coupled to the pump and the SCR system. A controller is communicatively coupled to the reductant insertion assembly. The controller is configured to initialize the pump so as to pressurize a reductant in the pump. The dosing valve is opened, thereby expelling the reductant into the SCR system. An operating electrical parameter value of the pump is determined which is indicative of an operating pressure of the pump. The controller determines if the operating electrical parameter value exceeds a predetermined operating threshold. If the operating electrical parameter value exceeds the predetermined operating threshold, the controller stops the pump.

First claim

What is claimed is:

1 . An aftertreatment system, comprising;
a selective catalytic reduction system including a catalyst for reducing constituents of an exhaust gas; a reductant storage tank; a reductant insertion assembly fluidly coupled to the reductant storage tank and the selective catalytic reduction system, the reductant insertion assembly comprising a pump and a dosing valve fluidly coupled to the pump; and a controller communicatively coupled to the reductant insertion assembly, the controller configured to:
initialize the pump so as to pressurize a reductant in the pump,
open the dosing valve, thereby inserting the reductant into the selective catalytic reduction system,
determine an operating electrical parameter value of the pump, the operating electrical parameter indicative of an operating pressure of the pump,
determine if the operating electrical parameter value exceeds a predetermined operating threshold, and
in response to the operating electrical parameter value exceeding the operating threshold, stop the pump.

2 . The aftertreatment system of claim 1 , wherein the operating electrical parameter value comprises a current consumed by the pump.

3 . The aftertreatment system of claim 1 , wherein the operating threshold comprises a threshold current value corresponding to a threshold pressure value of the pump.

4 . The aftertreatment system of claim 1 , wherein the reductant insertion assembly further comprises a dosing valve, and wherein the controller is configured to activate the dosing valve while the pump is stopped, the activating allowing the reductant to be inserted into the selective catalytic reduction system while the pump is stopped.

5 . The aftertreatment system of claim 4 , wherein the controller is further configured to restart the pump in response to the operating electrical parameter value falling below the operating threshold.

6 . The aftertreatment system of claim 3 , wherein the controller is configured to adjust a value of the operating threshold based on a value of an operating signal.

7 . The aftertreatment system of claim 6 , wherein the controller is configured to adjust a value of the operating threshold based on an operating temperature of the pump.

8 . The aftertreatment system of claim 1 , wherein the controller is further configured to:
determine an initial electrical parameter value of the pump on initializing the pump, the initial electrical parameter value indicative of an initial pressure of the pump; determine if the initial electrical parameter value exceeds a predetermined initial threshold; and in response to the initial electrical parameter value exceeding the initial threshold, stop the pump.

9 . The aftertreatment system of claim 1 , wherein the reductant insertion assembly does not include a pressure relief valve.

10 . A reductant insertion assembly, comprising:
a pump; a dosing valve fluid coupled to the pump; a sensing circuitry configured to sense one or more electrical parameters of the pump; and a controller communicatively coupled to the pump and the sensing circuitry, the controller configured to:
initialize the pump so as to pressurize a reductant in the pump,
open the dosing valve, thereby expelling a reductant therethrough,
determine an operating electrical parameter value of the pump via the sensing circuitry, the operating electrical parameter value indicative of an operating pressure of the pump,
determine if the operating electrical parameter value exceeds a predetermined operating threshold, and
in response to the operating electrical parameter value exceeding the operating threshold, stop the pump.

11 . The reductant insertion assembly of claim 10 , wherein the operating electrical parameter value comprises a current consumed by the pump.

12 . The reductant insertion assembly of claim 10 , wherein the operating threshold comprises a threshold current value corresponding to a threshold pressure value of the pump.

13 . The reductant insertion assembly of claim 10 , wherein the controller is further configured to activate the dosing valve while the pump is stopped, the activating allowing the reductant to be expelled through the dosing valve while the pump is stopped.

14 . The reductant insertion assembly of claim 13 , wherein the controller is further configured to restart the pump in response to the operating electrical parameter value falling below the operating threshold.

15 . The reductant insertion assembly of claim 12 , wherein the controller is configured to adjust a value of the operating threshold based on a value of an operating signal of the pump.

16 . The reductant insertion assembly of claim 12 , wherein the controller is configured to adjust a value of the operating threshold based on an operating temperature of the pump.

17 . The reductant insertion assembly of claim 10 , wherein the controller is further configured to:
determine an initial electrical parameter value of the pump on initializing the pump, the initial electrical parameter value indicative of an initial pressure value of the pump; determine if the initial electrical parameter value exceeds a predetermined initial threshold; and in response to the initial electrical parameter value exceeding the initial threshold, stopping the pump.

18 . A method of operating a reductant insertion assembly comprising a pump and a dosing valve structured to be fluidly coupled to an aftertreatment system, the method comprising;
initializing the pump so as to pressurize a reductant in the pump to an operating pressure of the pump; opening the dosing valve, thereby inserting a reductant into the aftertreatment system; determining if an operating electrical parameter value of the pump exceeds a predetermined operating threshold of the pump, the operating electrical parameter value indicative of the operating pressure of the pump; and in response to the operating electrical parameter exceeding the operating threshold, stopping the pump.

19 . The method of claim 18 , further comprising:
determining an initial electrical parameter value of the pump, the initial electrical parameter value indicative of an initial pressure value of the pump; determining if the initial electrical parameter value exceeds a predetermined initial threshold; and in response to the initial electrical parameter value exceeding the predetermined initial threshold, stopping the pump.

20 . The method of claim 18 , further comprising:
activating the dosing valve while the pump is stopped, the activating allowing the reductant to be inserted into the aftertreatment system while the pump is stopped.

21 . The method of claim 20 , further comprising:
restarting the pump in response to the operating electrical parameter value falling below the operating threshold.

22 . A control circuitry, comprising:
a controller configured to be communicatively coupled to a reductant insertion assembly including a pump, a dosing valve fluidly coupled to the pump and a sensing circuitry, the controller comprising,
a torque adjusting circuity configured to initialize the pump so as to pressurize a reductant in the pump,
a dosing control circuitry configured to open the dosing valve, thereby expelling a reductant therethrough, and
a pressure determining circuitry configured to determine an operating pressure of the pump via an operating electrical parameter value of the pump provided by the sensing circuitry, t

Assignees

• Cummins Emission Solutions Inc

Inventors

• Englert Tobias
• Honeck Jens

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F01N2610/144

  Control thereof · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N3/208 Primary

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

• F01N2390/02

  using electric components only · CPC title