Online determination of the quality characteristics for punch riveting and clinching
AssigneeBöllhoff Verbindungstechnik GmbH
InventorsAndreas Wenzel, Adnan Kolac
Life of this patent
Estimating the term…
Abstract
The present invention discloses a method for the online determination of a bulge/upset dimension xST and rivet head end position K of a rivet 3 with a length L in a punch rivet process with the help of a moveable punch 10 and a rigid die 20. The path covered by the punch 10 and the force applied by it are determined and evaluated online during the joining process. The quality characteristics of the joint connection are determined with the help of defined threshold values or a graphical evaluation of force/path data of the joining process.
Claims12
Online determination of bulge/upset dimension xST and rivet head end position KHS of a half-hollow punch rivet having a length L in a punch rivet process by means of a moveable punch and a die, comprising the following steps:
- a. capturing a path covered by a moveable punch during the punch rivet process with the help of a travel sensor,
- b. capturing a force F applied to the half-hollow punch rivet by the moveable punch during the punch rivet process depending on the covered path,
- c. determining an attachment point x2 of the half-hollow punch rivet with punch to a joint part and a release point x4 from the captured force/path data, while the release point x4 identifies a release of the punch after the punch rivet process and
- d. calculating the rivet head end position KHS in accordance with KHS=x2+L−x4 and bulge/upset dimension xST in accordance with xST=x−x4, where x is the maximum distance between facing sides of punch and die.
Online determination of embossing depth hd and rivet head end position KVS of a full punch rivet having a length L in a punch rivet process by means of a moveable punch and a die, comprising the following steps:
- a. capturing a path covered by a moveable punch during the punch rivet process with the help of a travel sensor,
- b. capturing a force F applied to the full punch rivet by the moveable punch during the punch rivet process depending on the covered path,
- c. determining an attachment point x2 of the full punch rivet with punch to a joint part and a release point x4 from the captured force/path data, while the release point x4 identifies a release of the punch after the punch rivet process and
- d. calculating the rivet head end position KVS in accordance with KVS=x2+L−x4 and the embossing depth hd in accordance with hd=t−[x−(x2+L)], where x is the maximum distance between facing sides of punch and die and t is a thickness of the joint parts.
Online determination according to claim l, comprising the further steps:
- capturing the applied force with a force sensor and
- storing the force/path data in a data processing unit, in particular a computer.
Online determination of a base thickness tb in a clinch process by means of a moveable punch and a die, which has the following steps:
- a. capturing a path covered by a moveable punch during the clinch process with the help of a travel sensor,
- b. capturing a force F applied to a joint part by the moveable punch during the clinch process depending on the covered path,
- c. determining a release point x4 from the captured force/path data, which identifies a release of the punch after the clinch process and
- d. calculating the base thickness tb in accordance with tb=x−x4, where x is the maximum distance between facing sides of punch and die.
Dependencies are inferred from the claim text.