Force Analysis of the Film in a COF Chip Mounter’s Loader

In this study, the tension force distributions in the film of COF cartridge are studied. It is noted that if the tension force on the film is too high, the interface between chip and film cracked. If the force is too low, there is no enough friction force to keep the COF in fix position when the cartridge is on the transportation vehicle. The relative motion between the chips of lower layer and the film of upper layer will cause the fatigue of interface of chips and film. It is also important to note that due to the friction the tension force at any section of the film is different. To fine the force distribution, a method to determine the tension force is developed and only effect of axial direction is considered. The assumption makes the film behave like a string. The results show that the forces on the film are different whenever the film passes a chip underneath.