Method for producing springs and spring machine for carrying out the method

Abstract

A method of manufacturing springs by a numerically controlled spring machine includes feeding a wire in a feed direction to a forming device of the spring winding machine by a feed device under control of a control program forming the wire into a spring with the aid of tools of the forming device in a forming operation, the forming device having a mandrel with a mandrel axis oriented at right angles to the feed direction, and windings of the spring surrounding the mandrel during the forming operation, and adjusting a position and/or orientation of the feed device with the aid of a controllable machine axis during the forming.

1 . A method of manufacturing springs by a numerically controlled spring machine comprising feeding a wire in a feed direction to a forming device of the spring winding machine by a feed device under control of a control program:
 forming the wire into a spring with the aid of tools of the forming device in a forming operation;   the forming device having a mandrel with a mandrel axis oriented at right angles to the feed direction, and windings of the spring surrounding the mandrel during the forming operation; and   adjusting a position and/or orientation of the feed device with the aid of a controllable machine axis during the forming.   
     
     
         2 . The method according to  claim 1 , wherein a spring having windings of different winding diameter is produced during the forming operation, and wherein the position and/or orientation of the feed device is/are changed during the forming operation such that the feed direction defined by the feed device always extends substantially tangentially to a winding of the spring just being produced. 
     
     
         3 . The method according to  claim 1 , wherein a spring having windings of different winding diameter is produced during the forming operation, and wherein the mandrel does not move at right angles to the mandrel axis during the forming operation. 
     
     
         4 . The method according to  claim 1 , wherein the spring machine is a spring winding machine and the mandrel is a winding mandrel rotatable about the mandrel axis by a rotary machine axis and rotated about the mandrel axis during the forming operation. 
     
     
         5 . The method according to  claim 4 , wherein a spiral spring is produced during the forming operation. 
     
     
         6 . The method according to  claim 4 , wherein, before manufacture of a spiral spring is begun, the position and/or orientation of the feed device is/are set such that a front wire end can be introduced into a transverse slit in the winding mandrel, after which the wire is then introduced into the transverse slit by the feed device, and after which the further forming operation then takes place, in which the wire is wound as the winding mandrel is rotated, the position and/or orientation of the feed device preferably being changed during the winding process such that the feed direction defined by the feed device always extends substantially tangentially to a winding of the spring just being produced. 
     
     
         7 . The method according to  claim 1 , wherein the spring machine is designed as a spring winding machine and has a cutting unit with a movable cutting tool that separates the finished spring from the fed wire, the mandrel being located inside the spring during the separation process and having a cutting edge which cooperates with the cutting tool during the separation process. 
     
     
         8 . The method according to  claim 7 , wherein, when a spring having windings of different winding diameter is manufactured, the position and/or orientation of the feed device is/are changed during the forming operation so that the mandrel rests against the inner face of the wire during each phase of the forming operation or is arranged at such a short distance from the inner face of the wire that, during a cutting operation, the mandrel immediately supports the wire against the action of the cutting blade. 
     
     
         9 . A spring machine that manufactures springs by spring winding or spring coiling under control of a control program comprising:
 a plurality of controllable machine axes;   a control device that coordinates control of axial movements of the machine axes of the spring machine on the basis of a control program;   a feed device that feeds wire (DR) in a feed direction (DZ) in a region of a forming device of the spring machine; and   a mandrel with a mandrel axis oriented at right angles to the feed direction, the mandrel being positioned or positionable such that windings of the spring surround the mandrel during the forming operation,   wherein   the feed device is an adjustable feed device in which the position and/or orientation of the feed device is/are adjustable with the aid of one of the controllable machine axes during production of a spring.   
     
     
         10 . The spring machine according to  claim 9 , wherein the machine axis associated with the feed device is controllable such that, during a forming operation for a spring having windings of different winding diameter, a feed direction (DZ) defined by the feed device always extends substantially tangentially to a winding of the spring just being produced. 
     
     
         11 . The spring machine according to  claim 9 , wherein the spring machine is a spring winding machine and the mandrel is a winding mandrel rotatable about the mandrel axis by a rotary machine axis, the winding mandrel additionally being movable parallel to the mandrel axis by a translatory machine axis. 
     
     
         12 . The spring machine according to  claim 9 , designed to carry out the method of manufacturing springs by a numerically controlled spring machine comprising feeding a wire in a feed direction to a forming device of the spring winding machine by a feed device under control of a control program:
 forming the wire into a spring with the aid of tools of the forming device in a forming operation;   the forming device having a mandrel with a mandrel axis oriented at right angles to the feed direction, and windings of the spring surrounding the mandrel during the forming operation; and   adjusting a position and/or orientation of the feed device with the aid of a controllable machine axis during the forming.   
     
     
         13 . The spring machine according to  claim 9 , wherein the spring machine is a spring winding machine,
 the forming device has at least one winding tool which basically determines the diameter of the coil spring in a predefinable position,   a cutting unit with a movable cutting tool that separates the finished spring from the fed wire is provided,   and the mandrel is located inside the spring during the separation of the spring and has a cutting edge (SK) which cooperates with the cutting tool (SW) during the separation process.   
     
     
         14 . The spring machine according to  claim 13 , wherein the mandrel is received in a mandrel casing and the mandrel casing is displaceable in a linear manner parallel to the mandrel axis, a controlled machine axis being provided for this displacement. 
     
     
         15 . The spring machine according to  claim 13 , wherein the mandrel and/or a mandrel casing supporting the mandrel is/are attached rigidly to the machine body of the spring winding machine such that the mandrel has no degrees of freedom of movement for controlled movements at right angles to the mandrel axis. 
     
     
         16 . The spring machine according to  claim 9 , wherein the feed device is movable by a translatory machine axis in a linear manner at right angles to the feed direction. 
     
     
         17 . The spring machine according to  claim 9 , wherein the feed device is pivotable in a controlled manner by a machine axis about a pivot axis extending parallel to the mandrel axis of the mandrel. 
     
     
         18 . The spring machine which is the spring winding machine that manufactures springs by spring winding or spring coiling under control of a control program comprising:
 a plurality of controllable machine axes;   a control device that coordinates control of axial movements of the machine axes of the spring machine on the basis of a control program;   a feed device that feeds wire (DR) in a feed direction (DZ) in a region of a forming device of the spring machine; and   a mandrel with a mandrel axis oriented at right angles to the feed direction, the mandrel being positioned or positionable such that windings of the spring surround the mandrel during the forming operation,   wherein   the feed device is an adjustable feed device in which the position and/or orientation of the feed device is/are adjustable with the aid of one of the controllable machine axes during production of a spring carries out the method according to  claim 1 .