Week 4:- Pin Unit Design Challenge
Aim:
Design 2 Different types of Fixed Pin Unit and Retractable Pin Unit with Different Pins, Riser, Blade, and Block and write a detailed report describing the process and attach relevant images.
Introduction:
A pin unit is single component in any fixture that is repsonsible in arresting the degrees of freedom of the panel that the fixture is holding. This is done with the help of multiple pin units on a single panel by using the 3-2-1 prinicple for locating.
Components of a Pin Unit:
The pin unit is functional only with the addition of certain components and these components have been created in this design and they are listed as below:
- Pin: The main component in the unit that assists in arresting the degrees of freedom of the panel
- Pin Retainer: The pin retainer is the component in the design on which the pin is fixed and this retainer is designed in a way such that it stops the rotation of the pin about its axis.
- Shims: The shim or spacer is component that is used for adjusting the position of the pin to match it up with the respective hole or slot in the case there is a stack up of tolerances which leads to the pin not placed in the hole correctly. In this case we use a 2 way shimming with shims of 0.5mm, 1mm and 2mm.
- Blade: This is the component that is used so that additional components that can be fixed on it if requried.
- Riser: The riser is a component that is used simply to give height to the rest of the design.
- L-Block: The L-blocks are used to provide the flexibility for the 2 way shimming which is required in this design.
Principle Of Locating for a Pin Unit:
- For arresting the panel properly in the required location, we mandatorily need 2 pins.
- The first we use will be a round pin and the second one is a diamond pin.
- The first pin will arrest the 4 degrees of translational motion of the panel.
- The second pin will arrest the 2 degrees of rotational motion of the panel.
- The pin should engage atleast 3-5mm from the entry surface of the panel that is fixed.
Models
1) Fixed Pin Unit (1st Design with Round Pin)
Front View
Isometric View
Top View
2) Fixed Pin Unit (2nd Design with Diamond Pin)
Front View
Side View
Isometric View
The following image shows both the fixed pin units holding the panel as it should be:
3) Retractable Pin Unit (1st Design with Round Pin)
Isometric View
Front View
Side View
4) Retractable Pin Unit (2nd Design with Diamond Pin)
Isometric View
Front View
Side View
The following image shows both the retractable pin units holding the panel as it should be:
Conclusion:
The Fixed and retractable pin units were designed with different designs and the required part files have been attached.