Lead screw prestretches device

The utility model discloses a lead screw prestretches device, including the lathe bed, the right -hand member internally mounted of lathe bed has a motor frame, and the left end inboard of motor frameis equipped with rear bearing cover gland, the left end outside joint of motor frame has the rear bearing cover, it constitutes by two semicircle ring method are blue to prestretch the flange, be equipped with the bearing spacer in prestretching the end bearing cover, the outside of bearing spacer is equipped with two bearings in succession, also is equipped with an accurate nut outside the bearing in the bearing spacer outside, the outer end that prestretches the end bearing cover is fixed with and prestretches end bearing cover gland, the left end of lead screw is also through the left accurate nut of external screw thread spiro union, the lathe bed edge of downside all is equipped with the line rail on the lead screw, and line rail outside edge is equipped with line rail briquetting. This lead screw prestretch