Abstract:
A high speed antifriction bearing (A, E, J) receives minute quantities of high performance grease or oil at selected intervals from an electrically controlled injector (D, H, I) having a nozzle (84, 184) that is directed at the rolling elements (6, 154) of the bearing. By minimizing the lubricant in the bearing, the lubricant does not accumulate in quantities that render it susceptible to working. The high performance lubricant produces a boundary layer film between contacting critical surfaces (14, 20, 30, 34, 36, 154, 156, 158) within the bearing. That film is so thin that it has little capacity to churn or work and produce heat. The injector may be the type used for electronic injection of diesel fuel into the cylinders of diesel engines.
Abstract:
A spindle (5) rotates within a housing (H) on at least two antifriction bearings (B,E) which have raceways (10, 16) that are inclined to the axis (X) of the bearing and are otherwise configured to transfer thrust loading as well as radial loading. The bearings are mounted in opposition. One of the bearings has a race (4) which fits into an actuator sleeve (68) with an interference fit, and the actuator sleeve, in turn, is fitted into the housing, it having end regions (88) that are located beyond the ends of the bearing. Here the sleeve is fitted to the housing with an interference fit and is further sealed to the housing. The actuator sleeve also has an intervening region (90) between its two end regions, and here the actuator sleeve is located around the race. On its opposite face the actuator sleeve forms a chamber with the housing. When the chamber is pressurized, the intervening region of the sleeve flexes inwardly and contracts the race, thus altering the setting of the two bearings. Yet the end regions of the sleeve remain against the housing and the axis of rotation remains rigid. A control system monitors conditions, such as temperature, within the housing, and varies the pressure in the chamber behind the actuator sleeve, so that the setting in the bearings best accommodates the conditions under which the spindle operates.