Abstract: Vacuum pumping apparatus includes a pump frame, a stationary scroll element secured to the pump frame, the stationary scroll element including a stationary scroll blade, an orbiting scroll element including an orbiting scroll blade intermeshed with the stationary scroll blade, a motor secured to the pump frame, and a crankshaft coupled between the motor and the orbiting scroll element for producing orbiting movement of the orbiting scroll blade relative to the stationary scroll blade when the motor is energized. The crankshaft includes a first component having a first coefficient of thermal expansion and a second component having a second coefficient of thermal expansion.

Abstract: A compact scroll pump includes a scroll set having an inlet and an outlet, and a drive mechanism. The scroll set includes a stationary scroll blade extending from a stationary plate and an orbiting scroll blade extending from an orbiting plate. The stationary and orbiting scroll blades are intermeshed together to define one or more interblade pockets. The orbiting scroll blade is located on a first side of the orbiting plate, and the drive mechanism is operatively coupled to a second side of the orbiting plate for producing orbiting motion of the orbiting scroll blade relative to the stationary scroll blade. The drive mechanism includes a motor and a crankshaft having an axis of rotation, and an orbiting bearing coupled between the crankshaft and the orbiting plate. The scroll set is configured such that an imaginary plane perpendicular to the axis of rotation passes through the orbiting bearing and at least a portion of the orbiting scroll blade.

Abstract: Vacuum pumping apparatus includes a scroll set having an inlet and an outlet. The scroll set includes a first stationary scroll blade and a second stationary scroll blade extending from a stationary plate and separated by a gap, and an orbiting scroll extending from an orbiting plate, wherein the first and second stationary scroll blades are intermeshed with the orbiting scroll blade to define one or more interblade pockets. The vacuum pumping apparatus further includes a relief port in the gap between the first and second stationary scroll blades and coupled through a relief passage to an exhaust, a relief valve in the relief passage, and a drive mechanism operatively coupled to the orbiting scroll element for producing orbiting motion of the orbiting scroll blade relative to the first and second stationary scroll blades.