Patent ID: 9399941
Filing Date: 2016-07-26
CPC Classification: F01N,F04B,Y02T

Claim Text:
1. A system for exhaust gas treatment of an internal combustion engine, comprising: a pump actuator having an actuating part of a magnetic piston movably mounted in a pole tube of a solenoid; a displacement piston pump providing a metered supply of a freezable substance, said pump having a pump piston interacting with a fluid chamber temporarily accommodating the freezable substance, said pump piston being movable by said actuating part of said pump actuator; a supply device in fluid communication with said piston pump introducing the substance in an exhaust gas flow; and a compensation device acting on said fluid chamber providing a volume expansion accompanying an increase of fluid pressure in said fluid chamber when the substance freezes as protection against damage to the system, said compensation device including a resilient component connected to said fluid chamber and having a predetermined resilience enabling said fluid chamber to enlarge in a pressure dependent manner, said pump actuator being a component of said compensation device and interacts with the compensation device via a resilient coupling permitting a pressure dependent relative motion between said pump piston and said pump actuator, said resilient coupling including a compression spring tensioned between said pump piston and said actuating part allowing said pump piston to move against a spring force of said compression spring and relative to said actuating part to enlarge said fluid chamber.