939003552 - INTRODUCTION - PANELS AND FRAME

Introduction

The topics are covered with particular attention to the new technical features required for passing the various tests introduced by new legislation. The descriptions and operating information provided are limited to a discussion of principles, rules and minimum precautions.For information on repair methods and vehicle specifications, see the specific sections on repair procedures.

Aerodynamics

The styling of the new car is designed to reflect great personality and originality and improves on the attributes of roominess, practicality and sturdiness achieved by previous models.The front, sides, rear and underbody were developed with particular attention to aerodynamics and allow outstanding drag coefficient values. The following values are an example:Version with basic specification:- drag coefficient CX = 0.32- drag coefficient for area CX x S = 0.7574These values are the result of road testing and measurements carried out in a wind tunnel.These results contribute to the noiselessness of the vehicle and significantly reduce wind noise. They also allow fuel saving.

Safety

The main aim of car manufacturers is definitely the total safety of the driver and passengers.To adapt the vehicle to highly demanding European and international market regulations, the new vehicle was designed with great attention to detail in order to achieve an optimum response in all situations.

Passive safety

A vehicle''s passive safety is the collection of technical and product solutions designed to protect the occupants of the vehicle in the case of an accident.The search for excellent performance has led to the introduction of design and construction solutions on the new vehicle that represent the state of the art in the field of passive safety.The occupant protection systemThe occupant protection system is composed of the following features fitted as standard on all trim levels:- the front protection system includes the electronic control unit, dual activation stage twin (driver and passenger) front air bags, driver and passenger knee bag, front seat belts with pretensioned buckle and load limiter in the reel, a control unit and safety sensor on the front tunnel, a additional decentralised impact detection sensor in the headlamp carrier crossmember, seat belt unfastened sensors for the front seats, occupant presence sensor on the passenger seat and passenger air bag manual disabling switch.- the chest/pelvic side protection system comprises two side bags in the front seats and two head/window bags along the roof side members- 3 point rear seat belts for all 3 rear seats.For more information on the Air Bag system    See descriptions 5580C AIR BAG SYSTEM The solutions adopted in the design and manufacture of the seats, the dashboard and the interior panels and fittings increase the degree of passive safety of the vehicle.For more information on these topics, refer to the specific chapters.Resistance to impactsAll the features relating to Passive Safety have been developed in order to offer the maximum protection for the occupant in all possible impact situations at high speed:- frontal impact- rear impact- side impact- roll overThe behaviour of the bodyshell in crash tests has more than adequately satisfied the international safety standards.Pedestrian protectionThe style of the front part of the vehicle has been developed taking into account the protection of pedestrians as required by the most recent international legislation. The shapes are smooth and rounded and there are no unsafe projections for the safety of pedestrians. The ample surface area of the bonnet minimizes the risk of contact between pedestrian''s heads and the rigid front pillars.The most rigid components are located inside the engine compartment a suitable distance away from the bonnet in order to allow the bonnet skin to absorb the energy forces of the impact with the pedestrian''s head.Protection against fireAt the end of the 90''s with the introduction of new European regulations regarding crash tests and with the introduction of fuel injection systems, the need to seriously redefine the design of the bodyshell and the layout of the various systems on the vehicle. The entire vehicle, from the bodyshell to the various components is therefore subject to the rigorous observance of the most recent and most stringent internal regulations regarding protection against fire.Fuel system and evaporation control system and fpsSpecial care has been taken over the layout to locate potentially critical devices outside of the impact area, also the routing of the various systems, which has been carefully considered from the earliest stages, is very well protected in order to reduce potentially critical situations.- The underbody fuel and evaporation control pipes are arranged parallel to the extremely strong underfloor side member. There is also a specific plastic duct to protect against accidental contact (stone chipping, etc.). In the engine compartment on the right hand side, metal sections of pipe have been used to prevent any fuel leaks in the case of contact during an impact.- The petrol versions have a returnless fuel system which allows the fuel return pipe to the tank to be dispensed with reducing the risk of leaks.- The evaporation control system active charcoal filter is located in the left rear wheel arch, in other words in an area that is not vulnerable and is near the tank.- There is an inertia switch on the petrol and diesel versions (FPS - Fire Prevention System) that immediately switches off the engine a few milliseconds after the start of the impact.- The plastic tank exceeds not only national but also foreign legal requirements. It is located in an area protected in the case of a collision and has the capacity to withstand any deformation without the risk of fuel leaks. Also, being plastic, there is no risk of explosion if the vehicle is on fire.Engine compartment electrical equipment- The positive battery terminal is not facing the direction of travel and the risk of short circuiting in the case of a frontal impact is thereby greatly reduced.- The main section of the high power positive leads is directly on the positive battery pole in a maxi fuse box. This solution prevents the presence of sections of cable not protected by fuses and therefore exposed to accidental short circuiting. There is also a series of automatic sectioning devices operated by the inertia switch (FPS) which, in the initial milliseconds following a serious impact, detach the battery connection to the high power leads averting the risk of a short circuit.- All the main cables are electrically insulated and fitted inside corrugated covers for mechanical protection against the possible risk of abrasion.- The electrical insulation of the starter motor/battery power lead is made from a material with good resistance to abrasion and cutting with the routing using special fastenings and protected by metal brackets.Passenger compartment interior electrical equipment- All the cables are protected by fuses located in the body computer control unit on the left side of the dashboard.- The routing of all the cables has been designed to prevent pinching during fitting or interference during operation and to reduce the potential risk of short circuiting to a minimum.Exhaust pipe- All the components that could suffer from radiated heat (reduced by the presence of a special shield) from the exhaust system have been located a suitable distance away.- Large metal shields on the underbody make it possible to protect the surrounding parts from the heat produced by the exhaust pipe (tank, handbrake cables, flexible supports).

The structure of the vehicle

The chassis

The chassis represents a radial structural change compared with the previous chassis of the 156.The chassis contains several ets of longitudinal box section structural elements, connected to one another by transverse elements and finished off by dashboard and floor panels.The floor panel box sections are integrated with the bodyshell elements, finishing off a perfectly integrated and solid structure.The absorption of energy from a frontal or rear impact is mainly carried out along the two load lines consisting of the front struts, engine mounting frame, rear struts, underfloor side members and side members. The continuity, for the entire length of the vehicle, of these three parts guarantees gradual defornation in accordance with the severity of the impact. In addition, the connection between the struts and the engine suspension frame contributes in distributing the load towards the deformed obstacle in the optimum way.The high resistance material and differentiated thicknesses of the front and rear side members are designed to support the forces developed by the front and rear crossmembers in the case of impacts at low speed without damage and, at the same time, to allow the absorption of all the impact energy in impacts at high speed without the passenger compartment being deformed.There is a box section crossmember at the front with controlled deformation collapsible struts (crash box), whilst there is a very thick crossmember at the rear with a collapsible open section.Both crossmembers are made from high resistance steel and are bolted onto the floor panel in order to facilitate servicing operations.Above the engine and in front of the H nodes there are a further two struts that intercept the stresses arriving from the top part of the vehicle through their deformation, especially when the vehicle crashes into the back of a lorry.There is a special box structure at the rear, immediately behind the rear seat backrest, constituting an extremely important structural element for the torsional strength of the bodyshell.The galvanizing treatment on both sides of all the chassis and bodywork structural elements and the use in some areas of increased galvanizing thickness panels, prevents the risk of rust, both structural and aesthetic and therefore guarantees the maintenance of structural performance for the entire life of the vehicle.

The bodywork

The bodyshell basically features three very important technical-technological factors: the use of high performance materials, the use of multi-thickness panels and the use of laser welding.The outer bodyshell, also to a great extent made from high resistance material (58% of the weight of the entire bodyshell is made from high resistance steel, whilst a further 7% of the weight of the entire bodyshell involves the use of dual-phase steel), represents a structure featuring numerous longitudinal, lateral and transverse box sections strengthened by internal reinforcement and featuring highly resistant sections.Dual-phase steel belongs to a family of high resistance steel which, on account of its metallurgical properties and chemical composition, features very good mechanical resistance properties (ferrite phase - very high yield and breaking loads) and excellent moulding properties (martensite phase - drawing depth) and are therefore particularly suitable for use on complex geometry panels which the bodyshell elements often are.Like for the chassis previously, the bodyshell has also made use of tailored-blank technology, in other words sheets of multi-thickness laser welded panels for the constructions of the most important structural elements, such as the side frame and the roof rib. Multi-thickness panels, compared with more traditional configurations where the elements are one single thickness with added local reinforcements, allows important improvements in terms of weight and technological sheel-metal working process (reduction in the number of weld spots).Laser seam welding, used both for indefinite panels (in the tailored-blanks mentioned above) and for finished elements (join between the roof outer cover and the side panels), which are then connected to one another without a continuity solution (in place of traditional spot welding) makes it possible to produce high quality, good performance structural joins.All these elements give the structure an extremely good torsional-bending strength and contribute to supporting the forces created by the centre side members in longitudinal impacts, whilst they play an important role in side impacts.An important contribution made by the good torsional strength is the elimination of creaking due to the torsion of the bodyshell and the interior and exterior fittings in operating conditions.Torsional rigidityDiagram showing deformation due to torsionTorsional rigidity valuesBodyshell with windows and bulkhead: 175400 daNm/radBending strengthDiagram showing deformation due to bending.Bending strength valuesBodyshell with windows and bulkhead: 1200 daN/mm.

The doors

The front and rear side doors are secured to the bodyshell by hinges and locks well above the minimum legislative standards and make an important contribution in both frontal and side impacts. A double high resistance steel lengthwise reinforcement along the waistline stabilizes the entire structure of the door and contributes to the non-deformability of the passenger compartment in a frontal impact.Experiments have confirmed that the doors do not open accidentally in various types of impacts, at the same time guaranteeing easy opening after an impact.Behaviour in terms of side impacts has improved with suitably sized ultra high resistant dual-phase steel crossmembers on all 4 doors.

The bonnet

Various safety measures have been introduced. There are preset collapse lines which, together with specific retaining hooks on the hinges, prevent it penetrating the windscreen in the case of an impact.

Windscreen and rearscreen

The fixed windows are a further safety feature.To increase the vehicle safety level, the windscreen is in laminated glass. This solution prevents the glass from shattering if struck by stones or gravel to assure visibility at all times and above all to offer a high level of protection if struck with the head.The windscreen and the rearscreen are bonded to the bodyshell, thereby contributing to increasing the structural strength of the vehicle: the seals flush with the bodywork contribute to reducing the noise due to oncoming air (wind noise).

The bumpers

They have been designed to provide excellent protection in the case of minor impacts.The rear crossmembers right behind the outer shell of both bumpers and the absorbers (for the rear with collapsible cell inserts) positioned between the bumper shell and the crossmember, limit damage in impacts at up to 4 km/h.

... DATA ERROR - CROPPED TEXT | Ошибка данных - Текст обрезан ...