The present invention relates to a lift device, which is especially suitable for use in a transfer assembly of a conveyor system. It is an object of this invention to provide an actuator or a compact and preferably modular non-pneumatic lifting device for a load that can provide a smooth lifting and lowering motion. According to the present invention, the lift assembly includes a first member, which is adapted for resting on a reference surface, and a second member which defines a support surface for a load. A drive assembly selectively moves the second member relative to the first member from an initial position to a final position. The drive assembly is adapted to move the second member from its initial position at a progressively increasing speed to an intermediate position and after which at a progressively decreasing speed until the second member is moved to its final position.