Technical constraints during vehicle manufacturing and assembly operations can require blind installation.
For example, on the Renault Mégane or the Dacia Duster, during the assembly operations, the operator can attach the rear window wiper mechanism or the soundproofing material to the under-engine fairing only from one side. Moreover, conventional attaching systems require fastener holes with tight tolerances.
These joining operations are traditionally carried out with bolted joints, using bolts and nuts or staples; that is, with two components. That requires the need for access from both sides to install the bolt and the nut. It also requires design work on the geometric scattering of the parts to be assembled, to refine the dimensional tolerances of the fastener holes.
As part of a strategy for continuous improvement, Renault and Böllhoff have taken into account the product/process constraints associated with the materials to be attached, in addition to the joining and installation equipment, and have investigated new technical solutions to meet increasingly stringent quality requirements.
On several models of vehicles produced by the Renault Group, whether for the installation of the rear window wiper or the soundproofing material of the under-engine fairing, the requirement is the same: attaching a thick plastic component to a thin steel plate or a thin plastic wall. And this operation involves three essential criteria:
- Quick installation with access on one side only, and safe for the operator
- Robust attachment throughout the service life of the vehicle
- Simple repair and maintenance of the assembled components
Rivquick slotted rivets are designed specifically to meet the requirements of automotive applications. This is the option selected by Renault and Böllhoff. The version with integrated plastic ring is described as being perfectly suited to the rear window wiper.
As a matter of fact, this technology offers major advantages. First, the rivets allow misalignment and fastener holes with significant geometric scattering. Second, there is no radial stress, which makes the slotted rivets compatible with thin and brittle materials, such as some plastics. Third, the attaching operation is fast and easy for the operator and features high vibration resistance, according to Bollhoff.
For those parts, bolted joints have been replaced with riveted joints. This now allows only one type of fastener to be used. In addition to eliminating the problem of operator accessibility for the installation of bolts and nuts, riveting is also simpler, faster and more economical.
In terms of product design, the Rivquick rivet allows for fastener holes with significant scattering, thereby making the design work easier and offering considerable savings on the design and manufacture of the parts to be assembled.
