The turntable of a vertical lathe is a rotating worktable component used for a vertical lathe. The worktable plane is placed on a horizontal plane, and the worktable surface can rotate continuously and steadily at a uniform speed. In addition to being able to withstand the gravity of the workpiece well, the turntable of a vertical lathe also needs to ensure high rotation accuracy and a certain operating speed and anti-overturning moment.
At present, the turntable structure of most vertical lathes is mostly a traditional structure. The turntable rotating guide rail generally adopts a rolling guide rail or a hydrostatic guide rail structure. The rolling guide rail is generally composed of 1 set of double-row cylindrical roller bearings and 2 sets of thrust bearings or 1 set of double-row cylindrical roller bearings (or 2 sets) and 1 set of plane thrust bearings. The end face runout and radial runout accuracy of the worktable include radial and axial accuracies respectively. These two accuracies need to be guaranteed by these 3 sets of bearings or 2 sets of bearings.
The existing vertical lathe turntable rolling guide structure has many types of bearings, many connecting parts, high manufacturing costs, and complex assembly structures. In addition, the errors of the connecting parts themselves are too large, which makes the turntable rotation accuracy unqualified. The hydrostatic guide turntable structure uses a hydrostatic oil cavity instead of a plane thrust bearing to bear the workpiece load and cutting force. The rest of the structure is the same as the rolling guide turntable structure.
In addition, the hydrostatic guide turntable structure also requires a hydraulic system, and a special shape of oil cavity needs to be designed and processed on the turntable parts, which increases the manufacturing cost and daily maintenance cost of the hydrostatic guide turntable structure. The selection of a set of turntable bearings of appropriate size can meet the requirements of the rotating worktable, thereby greatly simplifying the mechanical structure of the turntable components, saving machine tool space, lowering the center of gravity of the worktable, and lowering the center of gravity of the workpiece. At the same time, the performance of the worktable is still stable and reliable when it is subjected to a large eccentric load or overturning moment.
