Explosion-proof assembly for guiding through a stud, and method for producing same
The invention relates to an explosion-proof assembly ( 22 ) having an electrically conductive stud ( 23 ) made of a material which is not deformable radially. The stud ( 23 ) is coaxially surrounded in a central portion ( 23 a ) by an electrically insulating, electrically insulating sleeve ( 30 ). The sleeve ( 30 ) is in turn coaxially surrounded by a connecting portion ( 41 ) of a plastically deformable connecting body ( 40 ). Plastic deformation of the connecting portion ( 41 ) reduces the outer dimension thereof and the connecting portion ( 41 ) presses inwardly against the sleeve ( 30 ) to form a frictionally engaged form-fitting connection therebetween such that the connecting body ( 40 ), the sleeve ( 30 ) and the stud ( 23 ) form a structural unit with at least one stop surface ( 26 ) on the stud ( 23 ) resting against a counter stop surface of the sleeve ( 30 ).
1. An explosion-proof housing ( 20 ) comprising:
a wall structure that defines a flame-proof encapsulated area
an explosion-proof assembly ( 22 ) mounted within and extending through a wall ( 21 ) of said wall structure free of a flame ignition transmission gap between said explosion-proof assembly ( 22 ) and said wall ( 21 ),
said explosion-proof assembly including a non-deformable rigid electrically conductive stud ( 23 ) extending along a longitudinal axis (L) having a circumferential surface ( 25 ) extending around the longitudinal axis (L) and including a plurality of circumferential surface portions ( 25 a , 25 b , 25 c ), at least one of said circumferential surface portions ( 25 c ) forming a non-deformable rigid first stop surface ( 26 ) extending at an incline to the longitudinal axis (L),
an electrical insulating sleeve ( 30 ) made of an elastically deformable material having a sleeve inner surface ( 31 ) with a plurality of inner surface portions ( 31 a , 31 b , 31 c ), said sleeve inner surface ( 31 ) extending around the longitudinal axis (L) and resting against the circumferential surface ( 25 ) of the non-deformable rigid stud ( 23 ), at least one of the inner surface portions ( 31 c ) of the insulating sleeve ( 30 ) forming a first counter stop surface ( 32 ) which extends at an incline to the longitudinal axis (L) and which rests against said first non-deformable rigid stop surface ( 26 ),
a connecting body ( 40 ) surrounding at least one portion of the length of the sleeve ( 30 ) made of a plastically deformable material and having a plastically deformed connecting portion ( 41 ) pressing radially inwardly against the sleeve ( 30 ) for forming a frictionally engaged connection between the connecting body ( 40 ) and the sleeve ( 30 ) and between the sleeve ( 30 ) and the non-deformable rigid stud ( 23 ), and
said electrically conductive non-deformable rigid stud ( 23 ) being non-deformable under deformation forces on said connecting body ( 40 ) for pressing the connecting body ( 40 ) against the sleeve ( 30 ) for forming a frictionally engaged connection between the connecting body ( 40 ) and the sleeve ( 30 ) and between the sleeve ( 30 ) and non-deformable rigid stud ( 23 ) free of flame ignition transmission gaps.
2. The explosion-proof housing ( 20 ) of claim 1 in which said one first counter non-deformable rigid stop surface ( 32 ) is provided prior to the plastic deformation of the connecting portion ( 41 ).
3. The explosion-proof housing ( 20 ) of claim 1 in which said at least one first non-deformable rigid stop surface ( 26 ) is provided on an annular step of the non-deformable rigid stud ( 23 ).
4. The explosion-proof housing ( 20 ) of claim 1 in which said sleeve ( 30 ) has a sleeve outer surface ( 33 ) which rests against a passage surface ( 45 ) defined by a passage ( 44 ) extending through the connecting body ( 40 ) in the longitudinal direction (L).
5. The explosion-proof housing ( 20 ) of claim 4 in which said sleeve outer surface ( 33 ) has a plurality of outer surface portions ( 33 a , 33 b , 33 c , 33 d , 33 e ), and at least one of the outer surface portions ( 33 d , 33 e ) forms a second stop surface ( 34 ) extending at an incline to the longitudinal axis (L).
6. The explosion-proof housing ( 20 ) of claim 5 in which said passage surface ( 45 ) has a plurality of passage surface portions ( 45 a , 45 b , 45 c ), and at least one of said passage surface portions ( 45 c ) forms a second counter stop surface ( 46 ) which extends at an incline to the longitudinal axis (L) and which rests against said second stop surface ( 34 ) of said sleeve.
7. The explosion-proof housing ( 20 ) of claim 6 in which at least one of said second stop surface ( 34 ) of said sleeve and second counter stop surface ( 46 ) of said passage surface ( 45 ) is provided prior to the plastic deformation of the connecting portion ( 41 ).