Means for moving reciprocable carriages for indexible tool turrets in machine tools

In a machine tool, a combination comprising a support, a carriage reciprocable along said support from a first position to one of a plurality of second positions;

• means for biasing said carriage to said first position;
• and apparatus for advancing said carriage to a selected second position, comprising a movable cam, follower means tracking said cam and arranged to move said carriage from said first position in response to movement of said cam from a starting position, a rotary fluid power motor operable at a plurality of speeds, means for moving said cam in response to rotation of said motor, a fluid-operated braking device for arresting said cam in a selected second position of said carriage, a programming device receiving motion from said motor and having a plurality of output elements, and regulating means including a plurality of mobile input elements each arranged to receive motion from a different one of said output elements in respective preselected positions of said programming device, each of said angular positions corresponding to a second position of said carriage, said regulating means further including first and second valves for respectively controlling the speed of said motor and the operation of said braking device, first displacing means movable in response to movement of any one of said input elements to thereby actuate said first valve so as to reduce the speed of said motor, second displacing means for actuating said second valve with a delay following the movement of any one of said input elements to thereby operate said braking device while said motor rotates at reduced speed, means for arresting said motor substantially simultaneously with operation of said braking devices, and fluid-operated resetting means for normally maintaining said valves in conditions corresponding to an elevated speed of said motor and inoperative condition of said braking device, said braking device comprising means for actuating said arresting means so that said arresting means stops said motor in response to operation of said braking device.

In a machine tool, a combination comprising a support;

• a carriage reciprocable along said support from a first position to one of a plurality of second positions;
• means for biasing said carriage to said first position;
• and apparatus for advancing said carriage to a selected second position, comprising a movable cam, follower means tracking said cam and arranged to move said carriage from said first position in response to movement of said cam from a starting position, a rotary fluid power motor operable at a plurality of speeds, means for moving said cam in response to rotation of said motor, a fluid-operated braking device for arresting said cam in a selected second position of said carriage, said braking device comprising a cylinder block, a piston reciprocably mounted in said cylinder block and resilient means for biasing said piston to a first position in which said braking device is operative to arrest said cam, a programming device receiving motion from said motor and having a plurality of output elements and regulating means including a plurality of mobile input elements each arranged to receive motion from a different one of said output elements in respective preselected positions of said programming device, each of said angular positions corresponding to a second position of said carriage, said regulating means further including first and second valves for respectively controlling the speed of said motor and the operation of said braking device, said second valve having a valve member movable between first and second positions to thereby connect said block with a source of pressurized fluid whereby the fluid moves said piston to a second position corresponding to inoperative condition of said braking device, first displacing means movable in response to movement of any one of said input elements to thereby actuate said first valve so as to reduce the speed of said motor, second displacing means for actuating said second valve with a delay following the movement of any one of said input elements to thereby operate said braking device while said motor rotates at reduced speed, means for arresting said motor substantially simultaneously with operation of said braking device, fluidoperated resetting means for normally maintaining said valves in conditions corresponding to an elevated speed of said motor in inoperative condition of said braking device, a first conduit arranged to admit pressurized fluid to said motor and a second conduit arranged to receive spent fluid from said motor, said arresting means comprising a normally closed third valve connected between said conduits and said piston comprising means for opening said third valve in said first position thereof.