Axial-flow fluid machine, and variable vane drive device thereof

A variable vane drive device of an axial-flow fluid machine comprising:

• a movable ring which is in an annular shape and provided along an outer circumferential side of a plurality of variable vanes disposed annularly;
• a vane holding ring which encloses the outer circumferential side of the plurality of variable vanes and holds the plurality of variable vanes;
• a ring support unit which rotatably supports the movable ring with respect to the vane holding ring;
• and
• a driving force transmission unit, which includes a vane rotary shaft, a link piece, and a Connecting pin, and which connects the movable ring and the plurality of variable vanes in such a way that an angle of the plurality of variable vanes is changed by rotation of the movable ring,
• wherein the ring support unit comprises:
• a plurality of first rollers which makes a rolling contact with the movable ring;
• a first support part which supports the first rollers so as to be relatively immovable with respect to the vane holding ring in a radial direction and in an axial direction of the vane holding ring;
• one or more second rollers which make rolling contact with the movable ring;
• a second support part which supports the second rollers so as to be relatively movable with respect to the vane holding ring in the radial direction, and presses the second rollers in the radial direction toward a side at which the movable ring is pressed against the first roller;
• one or more third rollers which are disposed in such a way that a space is secured between the third rollers and the movable ring in the radial direction, allow relative movement of the movable ring in the radial direction, and restrict relative movement of the movable ring in the axial direction;
• and
• a third support part which supports the third rollers so as to be relatively immovable with respect to the vane holding ring in the axial direction and in the radial direction.