New Products Introduction of Infiniti Q30/QX30 Cockpit Module
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New products Introduction of Infiniti Q30/QX30 Cockpit Module Yuuya Miyazaki* Abstract Infiniti Q30/QX30 is the first premium compact segment model for Infiniti brand. This model is using Nissan’s partnership with Daimler to share the components of Daimler’s compact car architecture. It is the first European production car of the Infiniti brand produced at Nissan Motor Manufacturing UK Ltd.. Q30/QX30 has been developed to feature high-quality and luxurious design in its interior and exterior. This paper describes the CPM with such high-end specification beyond the entry-level premium segment. Key Words : Interior, Instrument panel / Cockpit module 1. Introduction One of our objectives in the CockPit Module (CPM) de- velopment for Infiniti Q30/QX30 (hereafter referred to as Q30) was to produce a luxurious interior that falls in the premium segment. In particular, to offer a rigid feel on the Instrument Panel (IP), the internal structure was enhanced from conventional products, and the glass-fi- ber reinforced polypropylene material was applied as our previous products in front end modules. To provide luxurious quality on the parts where customers acknowl- Fig. 1 Infiniti Q30 interior edge by viewing and touching, a vacuum bonding tech- (https://www.infiniti.com) nology was adopted for adhesion of skin and the upper IP surface, and soft pads were equipped with wrapped Remarkably, the pad specification at the passenger genuine leather that are three-dimensionally sewn with facing middle pad is selectable from genuine, Alcan- high quality stitches. tara, and synthetic leather materials, each of which has The following sections introduce our efforts on the CPM several color variations for the leather and stitches. The development. pad variations fulfill recent demands for personalization in the premium segments and provide higher qualities 2. Interior Specification than general entry class models. 2.1. Abundance of Skin Wrapping In addition, we established production and quality Fig. 1 shows the interior space of the Q30. In the pre- assurance processes that secured high quality appear- mium specifications, the skin is placed over the upper ances of the sewn parts, such as pitch and parallelism IP surface in the vacuum bonding process, whereas the of the finished stitches. upper pad at the driver side and the passenger facing middle pad are manually wrapped with the stitched skin pads which are adopted in many premium segments for presentation of craftsmanship. * CPM &Interior Business Unit, CPM & Interior Engineering Development Group 9 CALSONIC KANSEI TECHNICAL REVIEW vol.13 2017 Fig. 2 Infiniti Q30 interior passenger pad (https://www.infiniti.com) Fig. 4 Infiniti QX30 center-area interior real wood decoration (https://www.infiniti.com) 2.2. High Quality Decoration As a decorative accent, satin chrome plating is applied on the outer frame of the air conditioning grille to give 3. High Rigidity IP Structure fine and sophisticated impression. To render a premium 3.1. IP Structure sensation, the airflow adjuster dial is formed by double In the Q30 development, we put another effort on mak- injection, and it provides a soft touch feel and a visual ing the entire IP rigid to provide a premium feel. effect on airflow indication. Piano black finishing is ap- As shown in Fig. 5, the upper pad gets rigidity with plied around the audio switches as a standard specifica- open channels of air conditioning ducts that are closed tion while the real wood specification is provided as an by welding to the IP substrate. This is what we call a option. These specifications in the Q30 are superior to ducted structure. Conventionally, the upper pad must be those in general entry classes. rigid by itself. In the ducted structure, the upper pad has high rigidity with the duct sections. Fig. 5 Image of “ducted” structure Our conventional IP products already have a ducted Fig. 3 Infiniti Q30 center-area interior piano black paint decoration structure where only front edges of the IP are welded as (https://www.infiniti.com) shown in Fig. 6. In the Q30 as Fig. 7, the welding area is expanded to the entire IP for added rigidity. 10 Introduction of Infiniti Q30/QX30 Cockpit Module These characteristics improve the rigidity and heat resistance from the conventional structures. However, adoption of the PP+LGF required solutions for the fol- lowing issues: (A) Maintaining a remaining fiber length after molding (B) Preventing molding deformation Fig. 8 outlines that the fiber length has significant -in fluences on the PP+LGF material characteristics and indicates that a certain fiber length must remain to meet required characteristics. Comparing to the PPT, furthermore, molding deformation may typically occur due to anisotropic mold shrinkage with fiber influences. Fig. 6 Existing ducted structure welding area Fig. 8 Influence of remaining fiber length (image) 3.3. PP+LGF Molding Process Fig. 9 summarizes the fiber length which is shortened as the process proceeds from charging the material in Fig. 7 Q30 ducted structure welding area the molding machine to injecting in the molds. To mini- 3.2. IP Material Selection mize the cut fiber length, the generally used double flight Conventionally, the IP product was made of the polypro- screw was replaced with a single flight screw. In addi- pylene (PP) composites where talc was kneaded (called tion, the grade of the mold steel was changed to prevent PPT). The IP in the Q30 is made of the composites from wearing by the fiber. where glass fiber (GF) is kneaded to the PP. In detail, a long glass fiber is kneaded for the material composition (called PP+LGF) so that the material characteristics can be enhanced after molding as long as the fiber length is kept. Table 1 shows comparison of material characteristics between the PPT and the PP+LGF. Mainly, the PP+LGF has the following advantage over the PPT: (1) Higher rigidity (2) Higher heat resistance Table 1 Characteristic comparison of PPT and PP+LGF Characteristic PP+LGF PPT Flexual modulus (Mpa) 4450 2140 HDT (℃) 170 120 Fig. 9 Remaining fiber length in molding process (image) 11 CALSONIC KANSEI TECHNICAL REVIEW vol.13 2017 To suppress molding deformation, the fiber orientation 4.2. Compatibility of Formability and Design is optimized by identifying an appropriate gate position In the positive vacuum forming and bonding method, and an injection timing from resin flow analysis. In the because grain-textured skins are stretched to form the meantime, the molding conditions are adjusted so that convex shape, there are potential risks of failures, such weld is formed at a position where the IP strength is not as appearance degradation due to tensile elongation of affected. If deformation is not avoidable with adjusting the grain texture and skin fracture due to excessive the molding conditions, the IP shape is contrived. elongation during the forming process. To eliminate these risks, the elongation rate is estimated with vacu- um forming CAE analysis. If the analysis result shows a highly elongated area, the product shape and the produc- tion process are modified for uniform elongation. Since the upper IP surface at the passenger side is the most noticeable part to customers, we put great effort into finely adjusting the grain depth and size from the raw skin material for forming the optimum grain texture on product surfaces. Fig. 10 Warpage prediction by CAE analysis 4. Vacuum Adhesion Technology 4.1. Selection of Production Method Conventional Infiniti models adopted the IP structure where the skin was formed by powder slush molding and bonded to the substrate with urethane foam (cush- ion layer). Along the recent design trend of lowered and thinned upper pads, the IP in the Q30 is structured with the cushion-layer laminated skin that brings a benefit in minimizing the cushion layer thickness and provides a Fig. 12 Vacuum forming CAE analysis soft touch feel to customers. This structure allows reduc- tion of approximately 5 mm thickness and form of the product shape in conformity to the style intent. 5. Concluding Remarks There are generally various production methods for form- The CPM development for the Q30 concluded with the ing the laminated skin and bonding to the substrate. The highly superior quality product to other entry class pre- Q30 adopted the “Positive vacuum forming and bonding mium segments. In the future developments, we will ex- method” that forms the convex skin shape and bonds to pansively apply the technologies to other vehicle models. the substrate by vacuuming in one process (Fig. 11). Yuuya Miyazaki Fig. 11 Positive Vacuum forming and press process image 12.