Abstract: The drive member actuating rollers of an accumulating conveyor are independently supported by pneumatically inflatable tubing at a regulated pneumatic pressure engaging the drive member against the load carrying rollers to provide a drive force substantially no greater than that required to drive the load. Where the drive force is insufficient to overcome starting friction, the pneumatic pressure is periodically momentarily increased an amount sufficient to provide such drive force. In both cases, holdback force during accumulation is reduced to a minimum by matching the pressure of inflation to the drive force required for the load being conveyed, in a manner avoiding unnecessary excess drive force. In a long conveyor, the center section tubing is deflated during accumulation, to reduce holdback force.