Week 7:- Base Unit Design Challenges 1
what is the Base Unit? What are the typical parts of the Base Unit?
A base unit is a unit designed to mount all other units of tool like Pin Units, Clamp Unit, rest units etc. also penumatic Valve box and trunking chanel for cable path of various units thses necessary parts are mounted on the base unit.
Various parts of a base unit are shown in the diagram.
Trunking Channel- This is a chanel provided to accomodate electrical and pnematic hoses and cables of varoius units.
Base Plate-A base plate is a plate, made up of steel and aluminum on which holes for various units of a tool are drilled.
Valve Box- It is a standard part attached to base unit to accomodate all pneumatic valves.
Measuring Hole Cover- It is cover plate, purposely designed to cover the measuring holes of a base plate to avoid foreign particles or dust or burr to collect in measuring holes.
Eye Bolts- Eye bolts are used for transporting of a tool using lift hook. for the sa,e purpose, fork lift holes are provided in some cases.
Pedestal- This part connects base plate to floor plate. It can be a standard or a make part. it can be welded to base plate itself in some cases.
Weld Bars- Weld bar is a plate along sides of a base plate of a pedestal. They are used to weld the positions permanently.
Floor Plate ( Foundation Plate)- A floor plate is grouted to floor with fixed bolts.
What are the points need to account while designing a Base unit?
Points to be considered while designing a base unit.
Heigh of base unit- According to Height of panel and other units based on base unit, working height of the base unit is decided.
SIze of base plate- Base plate size shold be such that,it will cover all units.
Total Weigth of units on the base plate. Bas eplate thickness should be sufficient to hold entire weight of all units. It should be simple, economical and stirdy.
Level Adjustment- In order to align base unit exactly parallel to floor, there should be provision for adjutment.
Type of operations being performed on the station- BASe unit should hols all units firmly during operation conditions.
Design should be safe and ergonomically correct, depending upon type of work is performed.. like automatic or manual type.
Assembly and disassembly should be easy and convinient.
What is a Dump unit?
In special conditions, due to geometrical limitations of a panel, or space limitation if it is not easily possible to reach the location on panel to perform any specific operation, by a simple unit, a dump unit is used.
It is a complex type Unit, used if needed in special conditions.
complete assembly of a Unit( eg. Clapm Unit, Pin Unit) is assembled on a large size Dump Cylinder.
A dump unit can have more than one cylinder to perform the operations.
The first cylinder dumps the assembly carrying clamp mylars, pins and then this assembly performs the required operation.
load calculatoins, opening and closing conditions need to be consider for a dum unit.
What are the points you need to consider while designing a Dump unit?
Points to be considered while designing a Dump UNit-
Cylinder Validation based on total load by the unit
Total load of the unit- This load will decidesize of dump cylinder. Cylinder should be of suffeiceient power to holde the load of unit.
Proper Shock absorber to be used to avoid virations to transfer to panel.
Position of open and closed unit cylinders- shoulde be clear to all neighbouring parts of assembly.
A sensor should provided for assuracne presence of panel.
What is a Slide unit?
It is also a type of complex unit.
Generally used, when it is not easily possible to reach the spot location due to limitation of design.
A slding unit can be used to position the panel, fixture or weld gun, units or robots into position for further operations.
A sliding unit has following parts in general- Guides, Linear Cylinder, front and rear stoppers , fromt and rear stoppers, proximity seitches.
What are the points you need to consider while designing a Slide unit?
Following points should be considered while designing a slide unit-
Cylinder and GUide validation for load and stroke based on total load.
Shock absorber should be used in in extended and retractred end to reduce impact load.
Slide should be sensed by proximity sensor at proper position.
Slide should be locked at working postion using mechanical stopper.
Proper openeing and closing should be ensured.