In a vane motor, what holds the vanes out?

In a vane motor, the vanes are held out against the inner wall of the rotor by the action of springs. The springs exert a force that pushes the vanes outward, ensuring a tight seal against the internal surfaces of the motor. This is crucial for the effective operation of the vane motor, as it allows for proper fluid dynamics and pressure differentials that facilitate movement and power generation. The effective sealing provided by the outward position of the vanes helps to maximize the efficiency of the motor by ensuring that the hydraulic fluid can work effectively within the specified design parameters.

The other choices do not serve the function of holding the vanes outward. Hydraulic fluid aids in the operation of the motor but does not mechanically hold the vanes in position. Levers and gears are not components designed for this purpose in vane motors, as they relate to different mechanical functions within various types of machinery. Thus, the spring mechanism is central to the proper functioning of a vane motor.