Fluid container and reductant supply system with such a fluid container

Abstract

A fluid container for a motor vehicle, said container having a container wall which is made out of a plastic material and is provided with at least one metal resistance heating element. According to the invention the container wall is provided with at least one PPTC element as protection against overheating, said PPTC element beeing connected in series with the at least one heating element.

1 . A fluid container for a motor vehicle, said container having a container wall which is made out of a plastic material and is provided with at least one metal resistance heating element, wherein the container wall is provided with at least one PPTC element as protection against overheating, said PPTC element being connected in series with the at least one heating element. 
     
     
         2 . A fluid container according to  claim 1 , wherein the heating element ( 3 ) is provided with lamellar sections. 
     
     
         3 . A fluid container according to  claim 1 , wherein the heating element is cut out of sheet metal. 
     
     
         4 . A fluid container according to  claim 1 , wherein the heating element is embedded into the container wall. 
     
     
         5 . A fluid container according to  claim 1 , wherein the container wall, provided with the at least one heating element, forms a lateral wall. 
     
     
         6 . A fluid container according to  claim 1 , wherein the container wall, provided with the at least one heating element, forms a bottom wall. 
     
     
         7 . A fluid container according to  claim 1 , wherein the PPTC element is arranged on a surface of the container wall. 
     
     
         8 . A fluid container according to  claim 1 , wherein the PPTC element is embedded in the container wall. 
     
     
         9 . A fluid container according to  claim 1 , wherein the container wall is provided with several PPTC elements, 
     
     
         10 . A fluid container according to  claim 9 , wherein several heating elements are embedded in the container wall, which elements are connected in series with the PPTC elements. 
     
     
         11 . A fluid container according to  claim 1 , wherein a first chamber, that forms a fluid reservoir for the holding of fluid, and a second chamber, connected with the first chamber, that contains a filter material. 
     
     
         12 . A fluid container according to  claim 1 , wherein the electric resistance of the heating element amounts to at least 30 times the electric resistance of the PPTC element below its transition temperature. 
     
     
         13 . A fluid container according to  claim 1 , wherein the electric resistance of the PPTC element at room temperature is at most 0.5 ohm. 
     
     
         14 . A fluid container according to  claim 1 , wherein at room temperature the heating element has a total resistance of at least 2 ohms. 
     
     
         15 . A fluid container according to  claim 1 , wherein the container wall has a thickness of 3mm to 5mm. 
     
     
         16 . A fluid container according to  claim 1 , wherein the container wall is made out of a polyamide. 
     
     
         17 . A fluid container according to  claim 1  having a container volume of 200 ml to 300 ml. 
     
     
         18 . A fluid container according to  claim 1 , wherein a temperature sensor is embedded in the container wall. 
     
     
         19 . A fluid container according to  claim 1 , wherein the temperature sensor is a NTC element. 
     
     
         20 . A reductant supply system for a waste gas cleaning catalyst of an internal combustion engine, said reductant supply system comprising an electrically heatable fluid conduit for conveying reductant to a waste gas cleaning catalyst, and
 a pump for pumping reductant through the fluid conduit to the waste gas cleaning catalyst, wherein a fluid container according to  claim 1  is connected to the fluid conduit.