System for injecting a nitrogen oxides reducing agent into an exhaust line of an internal combustion engine vehicle
View Patent ↗Disclosed is a system for injecting an agent for reducing oxides of nitrogen into an exhaust line of an internal combustion engine vehicle, including: a pump for drawing the reducing agent from a tank and introducing it into the exhaust line; an injector for introducing the reducing agent into the exhaust line; an electronic unit for driving both the injector and the pump; a pipe for supplying the reducing agent linking the pump to the injector; an electrical cable for heating the supply pipe, the pump being arranged a certain distance away from the injector, and the electronic unit for driving both the injector and the pump being arranged in a module with the pump and connected to the injector via an electrical control cable, the latter being associated with the pipe for supplying the injector with the reducing agent.
1. A system for injecting an agent for reducing oxides of nitrogen into an exhaust line of an internal combustion engine vehicle, including:
a pump ( 12 ) for drawing the reducing agent from a tank and introducing it into the exhaust line;
at least one injector ( 13 , 102 ) for introducing the reducing agent into the exhaust line by injection;
an electronic unit ( 14 ) for driving both said at least one injector and the pump;
a pipe ( 17 , 30 , 103 ) for supplying said reducing agent linking the pump to said at least one injector;
an electrical cable ( 18 ) for heating the pipe for supplying the reducing agent,
the pump being arranged a certain distance away from said at least one injector, and the electronic unit for driving both said at least one injector and the pump being arranged in a module ( 10 ) with the pump and connected to said at least one injector via an electrical control cable ( 19 ), wherein the electrical control cable ( 19 , 35 , 110 ) is associated with said pipe for supplying said at least one injector with the reducing agent, the electrical control cable and the electrical heating cable consisting of a first single wire ( 110 ) and a second single wire ( 111 ) for the heating and control functionalities for said at least one injector ( 102 ), the injection system further comprising, in proximity to said at least one injector, or in said at least one injector itself, a diode means ( 112 ) between the first ( 110 ) and second ( 111 ) wires, which is connected in parallel with the actuator ( 108 ) of said at least one injector such that, the injection system comprising a device for reversing the control polarity:
in the reverse direction of the diode means ( 112 ), the current flows through the actuator ( 108 ) of said at least one injector ( 102 ); and
in the forward direction of the diode means ( 112 ), the current shorts the actuator ( 108 ) of said at least one injector ( 102 ) while providing the heating cable functionality.
2. The injection system as claimed in claim 1 , wherein the electrical control cable ( 19 , 35 ) is incorporated within the pipe ( 17 , 30 ) for supplying said at least one injector with the reducing agent.
3. The injection system as claimed in claim 2 , wherein the electrical control cable ( 19 , 35 ) is arranged within the hollow of the supply pipe ( 17 , 30 ) through which the reducing agent flows.
4. The injection system as claimed in claim 1 , wherein the electrical control cable ( 19 , 35 ) is affixed to the outer surface of the pipe ( 17 , 30 ) for supplying said at least one injector with the reducing agent.
5. The injection system as claimed in claim 1 , wherein the electrical control cable ( 35 ) and the electrical heating cable ( 36 ) share a common ground wire ( 37 ).
6. The injection system as claimed in claim 1 , wherein the resistance of the actuator ( 108 ) is at least five times as high as the resistances ( 107 ) of the first ( 110 ) and second ( 111 ) single wires for the heating and control functionalities for said at least one injector ( 102 ).
7. The injection system as claimed in claim 1 , wherein the static flow rate of the injector is dimensioned so as to achieve a required maximum flow rate of reducing agent by means of PWM control including a determined duty cycle of opening.
8. A method for injecting an agent for reducing oxides of nitrogen into an exhaust line of an internal combustion engine vehicle by means of an injection system as claimed in claim 1 , comprising:
heating the pipe ( 103 ) for supplying the reducing agent without controlling the injector ( 102 ) according to a first control polarity of said device for reversing the control polarity;
controlling said at least one injector ( 102 ) according to a second control polarity of said device for reversing the control polarity, which is the opposite of the first control polarity.
9. The injection method as claimed in claim 8 , wherein:
said at least one injector ( 102 ) is controlled by means of PWM control;
the pipe ( 103 ) for supplying the reducing agent is heated sequentially between the injector opening control phases by using the available time from the PWM control of said at least one injector ( 102 ).
10. The injection system as claimed in claim 1 , wherein the resistance of the actuator is 10 times as high as the resistances of the first and second single wires for the heating and control functionalities for said at least one injector.
11. The injection system as claimed in claim 1 , wherein the static flow rate of the injector is dimensioned so as to achieve a required maximum flow rate of reducing agent by means of PWM control including a duty cycle of opening of less than 50%.
12. The injection method as claimed in claim 8 , wherein:
said at least one injector is controlled by means of PWM control including a determined duty cycle of opening of less than 50%;
the pipe for supplying the reducing agent is heated sequentially between the injector opening control phases by using the available time from the PWM control of said at least one injector including a determined duty cycle of opening of less than 50%.
13. The injection system as claimed in claim 2 , wherein the electrical control cable and the electrical heating cable share a common ground wire.
14. The injection system as claimed in claim 3 , wherein the electrical control cable and the electrical heating cable share a common ground wire.
15. The injection system as claimed in claim 4 , wherein the electrical control cable and the electrical heating cable share a common ground wire.
16. The injection system as claimed in claim 2 , wherein the resistance of the actuator is at least five times as high as the resistances of the first and second single wires for the heating and control functionalities for said at least one injector.
17. The injection system as claimed in claim 3 , wherein the resistance of the actuator is at least five times as high as the resistances of the first and second single wires for the heating and control functionalities for said at least one injector.
18. The injection system as claimed in claim 4 , wherein the resistance of the actuator is at least five times as high as the resistances of the first and second single wires for the heating and control functionalities for said at least one injector.
19. The injection system as claimed in claim 5 , wherein the resistance of the actuator is at least five times as high as the resistances of the first and second single wires for the heating and control functionalities for said at least one injector.
20. The injection system as claimed in claim 2 , wherein the static flow rate of the injector is dimensioned so as to achieve a required maximum flow rate of reducing agent by means of PWM control including a determined duty cycle of opening.