Closure cp for a motor vehicle radiator

Abstract

A closure cap ( 10 ) for a fixed neck of a motor vehicle radiator is provided with a cap outer part ( 12 ), which comprises a closure element ( 17 ) that can be joined to the reservoir neck, and comprises a grip element ( 13 ) that is held in a manner that permits it to he twisted in relation to the closure element. A torsional stop ( 20 ) is provided between said closure element and grip element. The aim of the invention is to provide a closure cap of the aforementioned type with safety-relevant functions of the torsional stop and of the reduction of excess pressure in a structurally simple manner whereby permitting them to be exactly adapted to one another. To this end, an actuator ( 15 ) that can be expanded when subjected to heat is provided both for axially engaging and disengaging the coupling insert ( 46 ) of the torsional stop ( 20 ) as well as for adjusting the pretension with which the valve body ( 22 ) of the valve arrangement ( 11 ) is pressed against the sealing seat ( 21 ).

1 . A closure cap ( 10 ) for a fixed neck of a container, in particular a motor vehicle radiator, having a cap outer part ( 12 ), which has a closure element ( 17 ) that can be joined to a container neck and a grip element ( 13 ) retained rotatably relative to it, between which a torsional stop ( 20 ) is provided that has a coupling insert ( 46 ), which can be axially engaged and disengaged with and from the closure element ( 17 ) and is held in the grip element ( 13 ) in a manner fixed against relative rotation, for connecting the closure element and grip element in a way that is releasably fixed against relative rotation, and having a cap inner part ( 14 ), which has a fluidic connection between the container interior and the container exterior and a valve assembly ( 11 ) for enabling and blocking the fluidic connection, and a valve body ( 22 ) of the valve assembly ( 11 ) that can be moved back and forth is pressed toward the container interior against a sealing seat ( 21 ) on the cap inner part ( 14 ) with prestressing, in such a way that if a limit value of the container interior pressure is exceeded it can lift from the sealing seat ( 21 ), characterized in that an actuator ( 15 ) that is capable of expansion from heat is provided both for axial engagement and disengagement of the coupling insert ( 46 ) of the torsional stop ( 20 ) and for adjusting the prestressing with which the valve body ( 22 ) of the valve assembly ( 11 ) is pressed against the sealing seat ( 21 ).  
     
     
         2 . The closure cap of  claim 1 , characterized in that the actuator ( 15 ) is formed by an electrically heatable element of expansion material.  
     
     
         3 . The closure cap of  claim 1 , characterized in that the actuator ( 15 ) is formed by an electrically heatable absorption actuator, preferably a metal hydride actuator.  
     
     
         4 . The closure cap of at least one of the foregoing claims, characterized in that the actuator ( 15 ) is in operative communication with an electrical heating resistor ( 56 ), preferably a PTC resistor, whose trigger voltage is picked up by a temperature and/or pressure sensor associated with the container.  
     
     
         5 . The closure cap of  claim 4 , characterized in that the electrical heating resistor ( 56 ) is located on the underside of the actuator ( 15 ).  
     
     
         6 . The closure cap of at least one of the foregoing claims, characterized in that the actuator ( 15 ) is disposed inside the closure element ( 17 ), oriented toward the grip element ( 13 ).  
     
     
         7 . The closure cap of  claim 4 , characterized in that an electronic triggering unit ( 57 ,  58 ) is provided between the temperature and/or pressure sensor and the electrical heating resistor ( 56 ).  
     
     
         8 . The closure cap of  claim 7 , characterized in that the electronic triggering unit ( 57 ,  58 ) is disposed in the grip element ( 13 ).  
     
     
         9 . The closure cap of  claim 7 , characterized in that the electronic triggering unit ( 57 ,  58 ) is disposed in a plug of an electrical connecting line leading to the closure cap.  
     
     
         10 . The closure cap of  claim 9 , characterized in that the plug is connected to a counterpart plug ( 61 ) on the closure cap.  
     
     
         11 . The closure cap of at least one of the foregoing claims, characterized in that the valve body ( 22 ) is prestressed, facing away from the actuator ( 15 ), by a spring ( 28 ) which is braced, on its end remote from the valve body ( 22 ), on a pressure piece ( 29 ,  30 ) that in turn rests on the actuator ( 15 ).  
     
     
         12 . The closure cap of at least one of the foregoing claims, characterized in that the torsional stop ( 20 ) has a bracket ( 46 ), which rests by spring action on the actuator ( 15 ) and has terminal prongs ( 47 ), which can brought lockingly into an engagement with the male-threaded part ( 17 ) and can be released unlockingly.