Compensating device for a tool unit and fitting method by means of the tool unit

Abstract

A compensating device for a tool for fitting an element into a hole of a workpiece, the tool mounted axially on a housing by the compensating device, the compensating device having a clamping arrangement arranged between the tool and the housing and including at least two controllable clamping units. The clamping units are operable in an initial state to secure the tool rigidly to the housing, and in a compensating state to set different degrees of freedom defining possibilities of movement of the tool, and the compensating device also includes a control unit which is designed to activate the clamping units.

What is claimed is: 
     
         1 . A compensating device for a tool for fitting an element into a hole of a workpiece, the tool mounted axially on a housing by the compensating device, the compensating device comprising:
 a clamping arrangement located between the tool and the housing, and including two clamping units operable, in an initial state of the clamping arrangement, to secure the tool rigidly to the housing and, in a compensating state of the clamping arrangement, to set different degrees of freedom of the tool, the degrees of freedom defining possibilities of movement of the tool; and   a control unit operable to activate the clamping units.   
     
     
         2 . A compensating device according to  claim 1 , the clamping units arranged offset to one another along an axis of the tool. 
     
     
         3 . A compensating device according to  claim 1 , wherein at least one of the clamping units surrounds the tool in a circumferential direction transverse to an axis of the tool. 
     
     
         4 . A compensating device according to  claim 1 , wherein at least one of the clamping units includes a compressed-air hose. 
     
     
         5 . A compensating device according  claim 1 , wherein at least one of the clamping units includes a plurality of clamping elements arranged offset to one another in the circumferential direction. 
     
     
         6 . A compensating device according to  claim 5 , the plurality of clamping elements including one of a compressed-air hose and a clamping cylinder. 
     
     
         7 . A compensating device according to  claim 1 , and further comprising a rubber damper secured to the housing and on which the tool is mounted elastically to the housing. 
     
     
         8 . A compensating device according to  claim 1 , the compensating device further comprising an angular position transmitter operable to detect an angular position of the tool in three-dimensional space, the control unit coupled electrically to the angular position transmitter and operable to activate the clamping units on the basis of the angular position. 
     
     
         9 . A compensating device according to  claim 1  and further comprising a first force detection unit for measuring an axial setting force exerted upon the element by the tool in order to set the element in the workpiece, the control unit coupled electrically to the first force detection unit and operable to activate the clamping units on the basis of the fitting force. 
     
     
         10 . A compensating device according to  claim 1  and further comprising a second force detection unit arranged between the tool and the housing for detecting a deflecting force substantially transverse to an axis of the tool, and which deflecting force arises when the element is being fitted into the workpiece, and is exerted upon the element by the workpiece on account of an offset in position between the element and the hole, the control unit coupled electrically to the second force detection unit and operable to activate the clamping units on the basis of the deflecting force. 
     
     
         11 . A compensating device according to  claim 1 , wherein a maximum deflecting movement of the tool in the direction of the possibilities of movement is defined by the clamping units. 
     
     
         12 . A method for the automated fitting of an element into a hole of a workpiece with the aid of a tool mounted axially on a housing by a compensating device, the compensating device including a clamping arrangement with at least two controllable clamping units, and the fitting method comprising the steps of:
 setting of an initial state of the clamping arrangement so that the tool is secured rigidly to the housing;   automated feeding of the tool to the hole;   setting of a first degree of freedom for the tool unit by activating at least one of the clamping units;   introducing the element into the hole;   executing a setting process in order to set the element in the hole; and   setting a second degree of freedom for the tool, different from the first degree of freedom, by activating at least one other of the clamping units before and/or during the fitting process, and the degrees of freedom defining possibilities of movement of the tool unit.   
     
     
         13 . A fitting method according to  claim 12  and further comprising a step of: detecting an angular position of the tool in three-dimensional space, and the activating of the clamping units is carried out on the basis of the angular position. 
     
     
         14 . A fitting method according to  claim 12 , and further comprising a step of measuring a setting force, which is exerted upon the element by the tool in order to set the element, and the activating of the clamping units is carried out on the basis of the fitting force in order to set the possibilities of movement of the second degree of freedom. 
     
     
         15 . A fitting method according to  claim 12  and further comprising a step of measuring a deflecting force transverse to the axial direction and which is exerted upon the element by the workpiece during the fitting of the element into the workpiece on account of an offset in position between the element and the hole, and the activating of the clamping units is carried out on the basis of the deflecting force in order to set the possibilities of movement of the second degree of freedom. 
     
     
         16 . A blind rivet setting tool for setting a rivet in a workpiece, the blind rivet setting tool comprising:
 a housing;   a rivet tool for fitting the rivet into a hole of a workpiece, the rivet tool mounted axially to the housing, and   a compensating device located between the rivet tool and the housing, and whereby the rivet tool is mounted to the housing, the compensating device including:
 a clamping arrangement further including two clamping units which are operable, in an initial state of the clamping arrangement, to secure the rivet tool rigidly to the housing and, in a compensating state of the clamping arrangement to set different degrees of freedom of the rivet tool, the degrees of freedom defining possibilities of movement of the rivet tool, and 
 a control unit operable to activate the clamping units. 
   
     
     
         17 . A blind rivet setting tool according  claim 16  and further comprising: a first force detection unit coupled electrically to the control unit and operable for measuring a setting force, which is exerted upon the blind rivet by the rivet tool in order to set the rivet, and the control unit activates the clamping units on the basis of the fitting force.