Geplaatst op: 11-11-2019 | Solliciteren voor: 01-12-2019
Master Thesis Assignment
Design the perfect Driving Bridge
Philips is one of the world’s largest manufacturers of Hair Cutting devices such as Shavers, Hair Clippers and Beard Trimmers.
Many trimming devices have a cutting element that have a reciprocal movement, which is generated by an eccentric drive placed on a rotating motor axis.
Typical execution is an eccentric pin that moves in a plastic element having a slot, which is fixed to the cutting element. This plastic part is called ‘driving bridge’.
This is a crucial part of the device that can make or break a good performance.
Classical challenge is to have:
no play (to avoid vibrations, noise and performance loss)
little friction losses (e.g. low clamping force on the pin), since this would increase energy consumption which is not desired for battery operated devices.
within boundaries of feasible production tolerances.
Design, model and build an optimal driving bridge, having the following characteristics:
predictable performance, optimized for
Minimal friction losses; low spread in Torque required to drive the element
No or minimal play
High drive stiffness
and next to that takin into account
Compactness (allowing high design freedom)
Achievable tolerances for mass production
As a bonus, alternative rotation-to-translation transformation principles can be regarded.
Dynamic modeling & simulation
Stiffness calculation / FEM
Preferably include material behavior (e.g. relaxation when using plastics, wear)
Generate alternative concepts & improve existing concepts for rotation to translation
Make prototypes of several alternative concepts
Measure behavior (e.g. dynamic behavior & material behavior)
Ir. René van den Berg