<p>A module for a vending machine wherein two columns of shelves of substantially any conventional height can be operated successively upward through one column and then the other. The shelves are tripped successively by a vertically moving cam member, and as each shelf is tripped the shelf above it is readied for tripping upon subsequent actuation of the cam member. Each shelf has a pivoted support arm which rests on a ledge on the frame. This support arm is dislodged by a follower upon movement of the reciprocating cam member having a plurality of cam surfaces. As the shelf is tripped the follower on the shelf above the tripped shelf is moved to a position for engagement by the subsequent reciprocating of the cam member. A locking bar between parallel reciprocating cam members and a sequencing drive system permits their sequential operation to trip the shelves in one column and then in the next.</p>
