Cam device

A cam device comprising:

• a cam holder having a sliding contact surface;
• a cam slider having a sliding contact surface which is configured for sliding contact with the sliding contact surface of the cam holder to allow the cam slider to be freely movable in a predetermined process direction, a cam surface to move the cam slider in the predetermined process direction, and a mounting portion for mounting a process tool;
• and
• a cam driver having a cam surface, which is configured to contact with the cam surface of the cam slider, and is configured to forcedly move the cam slider in the predetermined process direction,
• wherein a combination of a material of a sliding surface made up of the sliding contact surface of the cam slider and a material of the sliding contact surface of the cam holder is the same as a combination of a material of a sliding portion made up of the cam surface of the cam driver and a material of the cam surface of the cam slider;
• and
• wherein the cam device is configured so that enlargement of the contact surface area due to conformity during the initial abrasion period is accelerated with use of the cam slider having an increased surface roughness of the sliding surface after a finishing process, and whereby a contact surface pressure is prevented from excessively increasing due to uneven contact caused by a mounting error of the cam device and a process error of a mold;
• and
• wherein the cam device is one that can be selected from groups of cam devices and to be replaced, and wherein each of the groups is determined depending on the basis of width dimensions of the cam device and including cam devices having different process abilities, so that a maximum process ability in a certain group among the groups is larger than a minimum process ability in an adjacent group of a larger width dimension, and smaller than the maximum process ability in another adjacent group of a smaller width dimension, such that a burden in changing a design of the cam device is reduced upon changing a process ability by changing the cam device.