Week 7- Base Unit Design Challenges 2
Aim: To design the Base unit for the given Car Panel.
Introduction:
The base unit supports the entire Car panel body, Risers, Clamps, Valve Box, pneumatic cylinder, etc for the given assembly. A base unit is a machined plate having a thickness between 20mm to 40 mm depending upon type the of assembly to be made.For the given Car panel Base plate is consider of thickness 20mm.
Fundamentals of Base Plate Design:
+The base plate should cover all the equipment /units along the outer periphery including the opening.
+A base Plate is preferred to the BCS coordinate system.
+No. of holes on base plate depends upon the size of BOX plate.
+Datum Holes should be drilled with nominal values in the 50s or 100s with a similar configuration. E.g.: X=650,Y=700.
+Datum holes should be covered with cover plates.
Components of Base Plate:
-Trunking channel: To guide the pneumatic line.
-Valve box: for the operation of solenoid valves.
-Measuring hole cover: to cover the holes that are drilled in the base plate for fitment of parts.
-eye bolts: To lift the whole assembly or for transportation.
-Pedestal: It connects the base plate to the floor plate. It is an STD. part & length may vary depending on height.
-Weld bar: It is a plate along the sides of the base plate of the pedestal.
Q2.
AIm: Arresting the DOF & providing proper supports for CAR Panel.
Introduction:
A car panel has to be rested on a separate rest unit which compromise of blades, risers, L bloc, etc. Generally for arresting the DOF 3-2-1 principle is to be followed. 3-2-1 principle states that by providing the pins in respective adjacent planes one can arrest the movement that the workpiece can move while undergoing the process.
The 1st no 3 indicates, 3Pins in 1st plane thereby restricting 4 rotational & 1 translation motion i.e total 5 dof are been arrested by just 3 pins. Further 2nd plane on any of the adjacent side has 2 pins which restrict 2 rotational & 2 translation motion.The last one pin restricts 3 translation motion there by arresting all the movements of the W/p.
2 Pins viz diamond headed or rounds pins are used to avoid the very movement of the different panel. Clamps/Mylars act as restricters to avoid the movement of panels in an upward direction.
3D:
https://drive.google.com/drive/folders/1PN8W3svhV_dZWMG6Wyvm4MUqd89afMT9?usp=sharing
Link: https://drive.google.com/drive/folders/1PN8W3svhV_dZWMG6Wyvm4MUqd89afMT9?usp=sharing