Roller Hemming Head Having a Replaceable Roller-Carrying Unit

Abstract

A roller hemming head having a quick-connection device which rigidly and removably connects a roller-carrying unit to the head lower portion. The quick-connection device includes spring means and an actuating member selectively engaged by an engagement member provided at a fixed station for quick replacement of the roller-carrying unit without cables and/or supply hoses for controlling the quick-connection device.

1 . Roller hemming head, comprising:
 an upper head portion, having a flange for connection to a wrist of a robot or other supporting movable equipment and   a lower head portion, carrying one or more hemming rollers, characterized in that said head further includes:
 a roller-carrying unit carrying the hemming rollers and adapted to be separated as a whole from the lower portion of the hemming head; 
 a quick-connection device which rigidly and removably connects said roller-carrying unit to said head lower portion; and 
 said quick-connection device comprising:
 spring means tending to hold said quick-connection device in a connection operative condition; 
 an actuating member movable against the action of said spring means for releasing the connection, and adapted to be operated by an engagement member, said engagement member being provided at a fixed station adjacent to said robot, or said other movable equipment for supporting the head, and being adapted to be received within a cooperating seat of the head; and 
 in such a way that said quick-connection device does not require the provision of cables or supply hoses on said robot or said supporting movable equipment. 
 
   
     
     
         2 . Roller hemming head according to  claim 1 , characterized in that said lower head portion comprises an outer cylindrical body slidably mounted on an inner cylindrical body forming part of said upper head portion and connected to said connecting flange. 
     
     
         3 . Roller hemming head according to  claim 2 , characterized in that said hemming head comprises an upper helical spring and a lower helical spring which are arranged coaxially aligned inside said inner cylindrical body, the ends of said upper and lower springs which are more remote from each other being applied against end elements of said inner cylindrical body, the ends of said upper and lower springs which are adjacent to each other being applied against opposite faces of an intermediate support element which is rigidly connected to said outer cylindrical body through diametrically opposite elements which are rigidly connected to said outer cylindrical body and are arranged through longitudinal slots of said inner cylindrical body
 said upper and lower springs being provided with a spring-guiding stem arranged axially through said springs and through said intermediate support element.   
     
     
         4 . Roller hemming head according to  claim 3 , characterized in that the ends of said upper and lower springs which are more remote from each other are applied against respective end elements of the inner cylindrical body with the interposition of two force sensors. 
     
     
         5 . Roller hemming head according to  claim 3 , characterized in that it is provided with first adjusting screw means for adjusting the load of said lower spring and second adjusting screw means for adjusting the load of said upper spring. 
     
     
         6 . Roller hemming head according to  claim 5 , characterized in that each of said first and second adjusting screw means comprises a screw rotatably mounted at an axially fixed position to a respective end of said inner cylindrical body, and an internally threaded bush, which is prevented from rotation with respect to said respective end element and is engaged by said screw said bush being further engaged on a threaded portion of a respective one of said force sensors which is associated with a respective one of said springs. 
     
     
         7 . Roller hemming head according to  claim 1 , characterized in that the lower spring has its lower end which is supported against a support disk provided with a cylindrical skirt having a shaped slot cooperating with a diametrical pin projecting from said spring-guiding stem so as to provide a bayonet coupling of said support disk on the lower end of said spring-guiding stem. 
     
     
         8 . Hemming fixed station, comprising a robot or other supporting movable equipment, and a hemming head according to anyone of the previous claims, carried by said robot or said supporting movable equipment. 
     
     
         9 . Hemming fixed station according to  claim 8 , characterized in that it comprises a fixed station adjacent to said robot or said movable equipment for supporting the head, said fixed station including an engagement member which is adapted to be engaged within a cooperating seat of the head, after that said robot or said supporting movable equipment has brought the head to a position adjacent to said fixed station, in order to operate the actuating member for releasing the connection. 
     
     
         10 . Hemming fixed station according to  claim 9 , characterized in that at said fixed station there is provided a movable magazine for roller-carrying units comprising a plurality of structures for receiving roller-carrying units, which are movable along an open or closed path, so that an empty receiving structure can be provided at a position for receiving the roller-carrying unit when the latter is uncoupled from the hemming head, whereas another receiving unit which is occupied by another roller-carrying unit can then be brought to said position for coupling said other roller-carrying unit with the hemming head.