Mounting system for cartridge engaging mechanism

摘要

A cartridge engaging assembly (10) may comprise a frame assembly (38) having a first side member (70) and a second side member (72) positioned in spaced-apart relation. A first horizontal guide surface (80) is positioned on the first side member (72) of the frame assembly (38) and a second horizontal guide surface (88) is positioned on the second side member (72) of the frame assembly (38). A thumb assembly (40) having first (75), second (89), and third (91) bearing members is positioned on the first and second horizontal guide surfaces (80, 88) so that the first bearing member (75) engages the first horizontal guide surface (80) and so that the second and third bearing members (89, 91) engage the second horizontal guide surface (88).