Design of backdoor

                                                                                                                        BACKDOOR CHALLENGE

AIM 

  To design a backdoor and provide the necessary embosses and reinforcements by usiing given styling surface.

Backdoors

 Backdoor/tailgate is the rearmost vehicle of the car design and its gives the access to the luggage area . The car backdoor has two different type of opening direction ( horizontally and vertically ) , its varries on their manufacturing conditions and consumer reqests.The opening angle if the backdoor is diifererd according to that region.During the rear crasg it absorbs the forces and distracted into the car body at all directions. 

                                                                                           

                                                                                                                         FIG :- Back door 

Designing criteria of a backdoor

• Rear visibility criteria 
• Gap and fllushness requirements
• Volume of the luggage area
• Rear crash regulations 
• Functional requirements of hinge and gas stay
• Mechanical force test 
• Tooling direction

Components of backdoor

• Tooling direction
• Backdoor outer panel ( upper)
• Backdoor outer panel ( lower)
• Backdoor inner panel
• Hinge reinforcements ( left and right)
• Gas stay reinforcements ( left and right )
• Striker reinforcement
• Wiper motor reinforcement.

Tooling direction 

Befire starting the design the tooilng direction is should be created. Tooling direction is most important one for manufacturing a product. if the tools works not properly the, products are not manufactured correctly. because od this tool,die and mold manufacturers are essential to the all succes of all other manufacturers. Proper tooling directluy affects the outputy capacity ,lifecycle and qualityof the product.

                                                                                          

                                                                                                          FIG- Tooling direction

Backdoor upper panel

The upper backdoor is copied ( extracted ) from the styling surface .

The thickness is developed on the inner panel of 0.75mm.

The required corner reliefs are provided on it .

Backside windshield glass is fixed on it.

                                                                                   

                                                                                                FIG :- Upper panel

                                                                                     

Backdoor lower panel

Backdoor lowe panel is copied from the styling surface .

The number plate and sometimes the side signal lights are developed on itb .

The thickness is developed on the lower panel of 0.75mm.

The required corner reliefs are provided on it. 

                                                                                    

                                                                                                FIG :-  Lower panel

Backdoor inner panel

Initially the inner panel is copied from the styling surfaces of both upper and lower panel.

Then the sealing flange is created by offsetting the inner panel with required dimensions , sealing flange gives the zero mm gap between the backdoor to the side fenders and roof edges . Its protecting the luggage area from water and other atmoshperic contents and give smooth opening and closing .

Hinge ,gas stay,striker and wiper motor reinforcements are developed on the surface of the inner panel.

The embosses are created on the lowe panel ,  during  the rear crash it absorbs the maximum amount of force and distracted into differenr directions , due to that the  luggage area doesnot affect heavily.

                                                                                  

                                                                                                   FIG:- Inner panel

Hinge (left and right ) and latch & striker reinforcements

 Hinges are used to opening and closing of a backdoor, during that opening and closing condition the its gives the balance to the backdoor . Due to the hinge mounting on tha inner panel some amount of strength lossed at their particular hinge mounting region , so additionaly some amount of rei nforcements 1.5mm  added at the hinge area.

 Strikers are used to lock the door . Its postioned by the trajectory . Mostly automotic controll mechanism or key opertated  mechanism is used to opening and closing.

                                                                                     

                                                                                               FIG:- Hinge reinforcement

                                                                                 

                                                                                                     FIG :- Striker reinforcement

Gasstay reinforcement 

  Gas stay is used to holding the bacdoor during the opening condition.Its gives the additional support to the hinge during the opening of backdoor. There are two types of gas stays are used generally fully automated gas stay, semi automated gas stay. In fully automated type no need manual support to lift the door its have a spindle to lift . In semi automated system manual support is need to lift the door initially.

                                                                                   

                                                                                              FIG :- Gas stay reinforcement

Wiper motor reinforcement 

 The wiper motor is positioned around the downside of the backside windshield glasses. The rain drops and other dust particles are wipeout by the wiper . The wioer is operated by the wiper motor. During the moving condition of a vehicle the wiper motor wil have some NVH issue , for avoiding this problem additional reinforcement is applied on that region .

                                                                                  

                                                                                             FIG :- Wiper motor reinforcement

 Draft analysis

  The draft analysis allows the user to easily analyze a part for proper draft angle . A draft angle  describes the amount of taper for molded or cast parts perpendicular to the parting line .

   Here  7 degree of angle is used as draft angle.

                                                                                     

                                                                                     

                                                                                                                      FIG :- Draft analysis

Hemming 

  Hemming is a forming operation in which the edges of the sheet are folded or folded over the anoter part in order to achieve a tigh fit . Normally hemming operations are used to connect parts together, to improve the appearance of a part and to reinforcement edges. 

In car production ,hemming is used in  assembly as a secondary operation after deep drawing , trimming and flanging o[erations to join two sheet metal parts (outer and inner ) together.

                                                                                    

                                                                                                             FIG:- Hemming

 Conclusion 

    The necessary embosses and reinforcements are created for the provided bacdoor surface .