To provide a supporting structure capable of stably supporting a drive in simple constitution, easily changing its setting position and to easily manufacture in a friction drive type conveyor.

A bridging material 31 provided with a large number of bolt holes 32, equally spaced in the longitudinal direction, is fixedly supported on a sleeper 30 of a rail 2 in parallel with the rail 2. The drive 25 comprising of a horizontal friction roller 28 to push and deliver a carriage 10 supported on the rail 2 and a motor 26 is supported on a tip end of an oscillating member 34 of support device 29 comprising of the oscillating member 34, a foundation frame 33, horizontally rotatably supporting a base edge of the oscillating member 34 and a lower edge of which is fixedly supported in the bolt holes 32 of the bridging material 31, and an energizing spring 35 of the oscillating member 34. The bolt hole for mounting the foundation frame 33 on the bridging material 31 is formed into a slot 33a, or it is favorable that an arm member 36 having a contact part 37 to make contact with a lower end of the rail 2 by projecting from a lower part is provided on the foundation frame 33, etc.