Patent ID: 9097252
Filing Date: 2015-08-04
Classification: F01C,F04C

Abstract:
1. A scroll pump comprising: a pump housing; an orbiting scroll; a fixed scroll; a drive shaft comprising a concentric shaft portion and an eccentric shaft portion, wherein the eccentric shaft portion is connected to the orbiting scroll, wherein the drive shaft is arranged to be driven by a motor so that during use, rotation of the drive shaft imparts an orbiting motion to the orbiting scroll relative to the fixed scroll for pumping fluid between a pump inlet and a pump outlet of the scroll pump, wherein the fixed scroll forms an opening through which the drive shaft extends, and wherein the drive shaft is connected to the orbiting scroll on an opposing side of the fixed scroll to the motor, wherein, during operation, the scroll pump provides a high vacuum region between the pump inlet and the pump outlet, and wherein, during operation, the scroll pump provides a low vacuum region including the opening of the fixed scroll through which the drive shaft extends; a lubricant free anti-rotation device, wherein the lubricant free anti-rotation device is located in the high vacuum region for resisting rotation of the orbiting scroll and allowing said orbiting motion; a first bearing for supporting rotation of the concentric shaft portion; a second bearing for supporting rotation of the eccentric shaft portion, wherein the first and the second bearings are located in the low vacuum region; and a counter-weight for balancing the weight of the orbiting components of the pump, wherein the counter-weight is located in the low vacuum region and adjacent to a scroll plate of the orbiting scroll.