Turret indexing assembly

Claim 2

A machine tool comprising a base, means connected with said base for holding a workpiece, rotatable turret means for holding a plurality of tools for performing work operations on the workpiece, releasable coupling means for holding said turret means against rotation relative to said base, said coupling means being operable between an engaged condition and a released condition in which said coupling means is ineffective to hold said turret means against rotation relative to said base, and indexing means operable through an indexing cycle to effect rotation of said turret means relative to said base, said indexing means including actuator means for operating said coupling means from the engaged condition to the released condition during an initial portion of the indexing cycle, drive means including a pair of cooperating gears for rotating said turret means after operation of said coupling means to the released condition during the initial portion of the indexing cycle, said actuator means being effective to operate said coupling means from the released condition to the engaged condition during a final portion of the indexing cycle after rotation of said turret means by said drive means, and holding means for holding said turret means against rotation during the initial and final portions of the indexing cycle independently of said pair of cooperating gears.

Claim 3

A machine tool comprising a base, means connected with said base for holding a workpiece, rotatable turret means for holding a plurality of tools for performing work operations on the workpiece, releasable coupling means for holding said turret means against rotation relative to said base, said coupling means being operable between an engaged condition and a released condition in which said coupling means is ineffective to hold said turret means against rotation relative to said base, and indexing means operable through an indexing cycle to effect rotation of said turret means relative to said base, said indexing means including actuator means for operating said coupling means from the engaged condition to the released condition during an initial portion of the indexing cycle, drive means including a pair of cooperating gears for rotating said turret means after operation of said coupling means to the released condition during the initial portion of the indexing cycle, said actuator means being effective to operate said coupling means from the released condition to the engaged condition during a final portion of the indexing cycle after rotation of said turret means by said drive means, and holding means for holding said turret means against rotation during the initial and final portions of the indexing cycle independently of said pair of cooperating gears.

Claim 4

A machine tool comprising a base, means connected with said base for holding a workpiece, rotatable turret means for holding a plurality of tools for performing work operations on the workpiece, releasable coupling means for holding said turret means against rotation relative to said base, said coupling means being operable between an engaged condition and a released condition in which said coupling means is ineffective to hold said turret means against rotation relative to said base, and indexing means operable through an indexing cycle to effect rotation of said turret means relative to said base, said indexing means including actuator means for operating said coupling means from the engaged condition to the released condition during an initial portion of the indexing cycle, drive means including a pair of cooperating gears for rotating said turret means after operation of said coupling means to the released condition during the initial portion of the indexing cycle, said actuator means being effective to operate said coupling means from the released condition to the engaged condition during a final portion of the indexing cycle after rotation of said turret means by said drive means, and holding means for holding said turret means against rotation during the initial and final portions of the indexing cycle independently of said pair of cooperating gears.

Claim 5

A machine tool as set forth in claim 1 wherein said means for holding said turret means includes a retaining member operatively connected with one gear of said pair of cooperating gears and means operatively connected with the other gear of said pair of cooperating gear for engaging said retaining member during the initial and final portions of the indexing cycle to hold said one gear against rotational movement.

Claim 6

A machine tool as set forth in claim 2 wherein said retaining member is an escapement wheel having a plurality of arms and said means for engaging said retaining member includes locking surface means which engages at least one of said arms during the initial and final portions of the indexing cycle to retain said one gear against rotational movement.

Claim 7

A machine tool as set forth in claim 1 wherein at least one gear of said cooperating pair of gears includes a first portion which is effective to rotate the other gear of said cooperating pair of gears during rotation of said turret means by said drive means and a second portion which is ineffective to rotate the other gear of said cooperating pair of gears upon rotation of said one gear during the initial and final portions of the indexing cycle.

Claim 8

A machine tool as set forth in claim 4 wherein said holding means includes an escapement wheel connected with said other gear of said pair of cooperating and a retaining means connected with said one gear of said pair of cooperating gears, said retaining means being disposed in engageMent with said escapement wheel to hold said other gear against rotational movement.

Claim 9

A machine tool comprising a base, means on said base for holding a workpiece, rotatable turret means for holding a plurality of tools, drive means for rotating said turret means, said drive means including first and second rotatable gears, said first gear being movable into and out of meshing engagement with said second gear, a retaining member operatively connected with said second gear, and holding means operatively connected with said first gear for engaging said retaining member to hold said second gear and said turret means against rotation relative to said base during movement of said first gear into and out of meshing engagement with said second gear.

Claim 10

A machine tool comprising a base, means on said base for holding a workpiece, rotatable turret means for holding a plurality of tools, drive means for rotating said turret means, said drive means including first and second rotatable gears, said first gear being movable into and out of meshing engagement with said second gear, a retaining member operatively connected with said second gear, and holding means operatively connected with said first gear for engaging said retaining member to hold said second gear and said turret means against rotation relative to said base during movement of said first gear into and out of meshing engagement with said second gear.

Claim 11

A machine tool as set forth in claim 6 further including releasable coupling means for holding said turret means against rotation, said coupling means being operable between an engaged condition in which said turret means is held against rotation relative to said base by said coupling means and a disengaged condition in which said coupling means is ineffective to hold said turret means against rotation relative to said base, said holding means being disposed in engagement with said retaining member during operation of said coupling means between the engaged and disengaged conditions to thereby hold said turret means against rotation relative to said base during engagement and disengagement of said coupling means.

Claim 12

A machine tool as set forth in claim 6 wherein said retaining member is an escapement wheel having a plurality of outwardly extending arms, said holding means including means mounted for rotation with said first gear and movable into engagement with said arms of said escapement wheel during movement of said first gear into and out of meshing engagement with said second gear to hold said escapement wheel and second gear against rotation.

Claim 13

A machine tool as set forth in claim 8 wherein said means mounted for rotation with said first gear includes a carrier member and a plurality of rollers mounted on said carrier member, said rollers being movable into engagement with said arms of said escapement wheel by rotation of said first gear to hold said second gear against rotation relative to said base.

Claim 14

A machine tool comprising a base, means connected with said base for holding a workpiece, rotatable turret means for holding a plurality of tools for performing work operations on the workpiece, releasable coupling means for holding said turret means against rotation relative to said base, said coupling means being operable between an engaged condition in which said coupling means is effective to hold said turret means against rotation relative to said base and a disengaged condition in which said coupling means is ineffective to hold said turret means against rotation relative to said base, indexing means operable to effect rotation of said turret means relative to said base during an intermediate position of an indexing cycle to thereby change the positions of the tools relative to the workpiece, said indexing means including actuator means for operating said coupling means from the engaged condition to the disengaged condition during an initial portion of the indexing cycle to release said turret means for rotation during the intermediate portion of the indexing cycle and for operating said coupling means for the disengaged condition to the engaged condition during a final portion of the indexing cycle to hold said turret means in a position to which it is rotated during the intermediate portion of the indexing cycle, first and second rotatable gears, said first gear including a drive segment and a positioning segment, said second gear including a drive segment for meshing with said drive segment of said first gear during the intermediate portion of the indexing cycle to effect rotation of said gears and said turret means relative to said base and indexing segments for cooperating with said positioning segMent on said first gear during the initial and final portions of the indexing cycle, retaining means connected with one of said gears and escapement means connected with the other of said gears for cooperating with said retaining means to hold said second gear and said turret means against rotation relative to said base as said coupling means is operated between the engaged and disengaged conditions during the initial and final portions of the indexing cycle, said retaining means and said escapement means being movable between a holding condition in which said second gear and said turret means are held against rotation relative to said base and a release condition in which said second gear and said turret means are rotatable relative to said base, and drive means for rotating said first gear relative to said second gear with said positioning segment on said first gear in a cooperating relationship with one of said indexing segments on said second gear to move said drive segment on said first gear toward a position of meshing engagement with said drive segment on said second gear and for effecting operation of said actuator means to operate said coupling means to the disengaged condition with said retaining means and said escapement means in the holding condition to thereby hold said second gear and turret means against rotation as said coupling means is disengaged during the initial portion of the indexing cycle, said drive means being operable during the intermediate portion of the indexing cycle to move said retaining means and said escapement means into the release condition and to continue rotation of said first gear with said drive segments in a meshing relationship to effect rotation of said second gear and said turret means, said drive means being operable during the final portion of the indexing cycle to move said positioning segment on said first gear into cooperating relationship with one of said indexing segments on said second gear, to move said retaining means and said escapement means into the holding condition, and to effect operation of said actuator means to operate said coupling means to the engaged condition while said retaining means and said escapement means are in the holding condition to thereby hold said turret means in the position to which it was rotated during the intermediate portion of the indexing cycle.

Claim 15

A machine tool comprising a base, means connected with said base for holding a workpiece, rotatable turret means for holding a plurality of tools for performing work operations on the workpiece, releasable coupling means for holding said turret means against rotation relative to said base, said coupling means being operable between an engaged condition in which said coupling means is effective to hold said turret means against rotation relative to said base and a disengaged condition in which said coupling means is ineffective to hold said turret means against rotation relative to said base, indexing means operable to effect rotation of said turret means relative to said base during an intermediate position of an indexing cycle to thereby change the positions of the tools relative to the workpiece, said indexing means including actuator means for operating said coupling means from the engaged condition to the disengaged condition during an initial portion of the indexing cycle to release said turret means for rotation during the intermediate portion of the indexing cycle and for operating said coupling means for the disengaged condition to the engaged condition during a final portion of the indexing cycle to hold said turret means in a position to which it is rotated during the intermediate portion of the indexing cycle, first and second rotatable gears, said first gear including a drive segment and a positioning segment, said second gear including a drive segment for meshing with said drive segment of said first gear during the intermediate portion of the indexing cycle to effect rotation of said gears and said turret means relative to said base and indexing segments for cooperating with said positioning segMent on said first gear during the initial and final portions of the indexing cycle, retaining means connected with one of said gears and escapement means connected with the other of said gears for cooperating with said retaining means to hold said second gear and said turret means against rotation relative to said base as said coupling means is operated between the engaged and disengaged conditions during the initial and final portions of the indexing cycle, said retaining means and said escapement means being movable between a holding condition in which said second gear and said turret means are held against rotation relative to said base and a release condition in which said second gear and said turret means are rotatable relative to said base, and drive means for rotating said first gear relative to said second gear with said positioning segment on said first gear in a cooperating relationship with one of said indexing segments on said second gear to move said drive segment on said first gear toward a position of meshing engagement with said drive segment on said second gear and for effecting operation of said actuator means to operate said coupling means to the disengaged condition with said retaining means and said escapement means in the holding condition to thereby hold said second gear and turret means against rotation as said coupling means is disengaged during the initial portion of the indexing cycle, said drive means being operable during the intermediate portion of the indexing cycle to move said retaining means and said escapement means into the release condition and to continue rotation of said first gear with said drive segments in a meshing relationship to effect rotation of said second gear and said turret means, said drive means being operable during the final portion of the indexing cycle to move said positioning segment on said first gear into cooperating relationship with one of said indexing segments on said second gear, to move said retaining means and said escapement means into the holding condition, and to effect operation of said actuator means to operate said coupling means to the engaged condition while said retaining means and said escapement means are in the holding condition to thereby hold said turret means in the position to which it was rotated during the intermediate portion of the indexing cycle.