Multi-spindle machine tool heads

Claim 2

A multi-spindle drilling and reaming unit comprising a casing including means defining a front face having a plurality of spaced bores therein, and means defining a rear face, a plurality of spindles, each of said bores corresponding to and accommodating one of said spindles, means enabling each spindle of said plurality of spindles to be removed from and replaced in the casing from the front face thereof, each said enabling means comprising thrust-accommodating bearings removable together with the spindle from said front face, toothed gearing for driving said spindle, means for releasably retaining said spindle in one of the corresponding bores of the unit, and means for preventing rotation of one component of said thrustaccommodating bearings relative to the casing when located therein and locked by said means for releasably retaining said spindle in the casing.

Claim 3

A multi-spindle drilling and reaming unit comprising a casing including means defining a front face having a plurality of spaced bores therein, means defining a rear face, a plurality of spindles, each of said bores corresponding to and accommodating one of said spindles, means enabling each spindle of said plurality of spindles to be removed from and replaced in the casing from the front face thereof, each said enabling means comprising thrust-accommodating bearings removable together with the spindle from said front face, toothed gearing for driving said spindle, means for releasably retaining said spindle in one of the corresponding bores of the unit, a cartridge shell housing said spindle and said thrust-accommodating bearings, said shell having an internal screw thread, said retaining means acting to retain said cartridge shell to said casing, and an externally-threaded sleeve received in said internal screw thread of the cartridge shell and engaging one component of the thrust-accommodating bearings to prevent rotation thereof relative to said shell, said thrust-accommodating bearings having the form of a stack of angular contact bearings.

Claim 4

A multi-spindle drilling and reaming unit comprising a casing including means defining a front face having a plurality of spaced bores therein, means defining a rear face, a plurality of spindles, each of said bores corresponding to and accommodating one of said spindles, means enabling each spindle of said plurality of spindles to be removed from and replaced in the casing from the front face thereof, each said enabling means comprising thrust-accommodating bearings removable together with the spindle from said front face, toothed gearing for driving said spindle, means for releasably retaining said spindle in one of the corresponding bores of the unit, a cartridge shell housing said spindle and said thrust-accommodating bearings, said shell having an internal screw thread, said retaining means acting to retain said cartridge shell to said casing, and an externally-threaded sleeve received in said internal screw thread of the cartridge shell and engaging one component of the thrust-accommodating bearings to prevent rotation thereof relative to said shell, said thrust-accommodating bearings having the form of a stack of angular contact bearings.

Claim 5

A unit in accordance with claim 2 wherein said cartridge shell has a bore with a shoulder at one end abutting an opposed portion of said one component of said tHrust-accommodating bearings, and an external flange along its length by which it is secured to the front face of said casing.

Claim 6

A unit in accordance with claim 3 wherein the shoulder lies at a position along the length of the shell corresponding to the position of the flange.

Claim 7

In a multi-spindle drilling and reaming unit, a casing including means defining a front face having a plurality of stepped bores at predetermined spacings from one another, means defining a rear face, a plurality of spindles corresponding to the plurality of bores, each of said bores corresponding to and accommodating one of said spindles, means enabling each spindle of said plurality of spindles to be removed from and inserted into one of the corresponding bores of the casing from the front thereof, each said enabling means comprising a gear wheel, a shaft secured for rotation with the gear wheel, a first journal bearing supporting said shaft in the means defining the rear face, spline means coupling the shaft for positive rotation with said spindle while permitting relative axial motion, a second journal bearing supporting the spindle adjacent said gear wheel, a thrust-resisting bearing disposed to carry the spindle adjacent to the front of said means defining the front face of the casing, said bearing including an inner race, an outer race, and two rows of bearing elements disposed between the races, means locking the inner said race on said spindle, a cover plate, means for securing the cover plate to said means defining the front face of the casing, and a distance piece surrounding the spindle and interposed between the cover plate and said outer race, whereby the action of tightening the cover plate onto the means defining the front face of the casing serves to lock the outer race against the step of the corresponding bore and to prevent rotation of the outer race relative to the casing, release of said cover plate serving to free the outer race of the thrust-resisting bearing and subsequent axial withdrawal of the spindle being permitted by sliding of the outer race in the bore and relative axial sliding motion of said spline means.

Claim 8

In a multi-spindle drilling and reaming unit, a casing including means defining a front face having a plurality of stepped bores at predetermined spacings from one another, means defining a rear face, a plurality of spindles corresponding to the plurality of bores, each of said bores corresponding to and accommodating one of said spindles, means enabling each spindle of said plurality of spindles to be removed from and inserted into one of the corresponding bores of the casing from the front thereof, each said enabling means comprising a gear wheel, a shaft secured for rotation with the gear wheel, a first journal bearing supporting said shaft in the means defining the rear face, spline means coupling the shaft for positive rotation with said spindle while permitting relative axial motion, a second journal bearing supporting the spindle adjacent said gear wheel, a thrust-resisting bearing disposed to carry the spindle adjacent to the front of said means defining the front face of the casing, said bearing including an inner race, an outer race, and two rows of bearing elements disposed between the races, means locking the inner said race on said spindle, a cover plate, means for securing the cover plate to said means defining the front face of the casing, and a distance piece surrounding the spindle and interposed between the cover plate and said outer race, whereby the action of tightening the cover plate onto the means defining the front face of the casing serves to lock the outer race against the step of the corresponding bore and to prevent rotation of the outer race relative to the casing, release of said cover plate serving to free the outer race of the thrust-resisting bearing and subsequent axial withdrawal of the spindle being permitted by sliding of the outer race in the bore and relative axial sliding motion of said spline means.

Claim 9

A unit according to claim 5 wherein said thrust-resisting bearings are axially staggered in adjacent bores.