Rod stock feed means

Claim 1

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said gripper actuator means including a piston and cylinder assembly connected with said gripper means and control means for activating said piston and cylinder assembly to effect operation of said gripper means between its open and closed conditions, said piston and cylinder assembly including a piston and cylinder which are movable relative to each other through a First operating stroke upon activation of said piston and cylinder assembly to effect operation of said gripper means from its open condition when a piece of bar stock is disposed within said gripper means, said piston and cylinder being movable relative to each other through a second operating stroke which is larger than said first operating stroke upon activation of said piston and cylinder assembly to effect operation of said gripper means from its open condition without a piece of bar stock disposed within said gripper means.

Claim 2

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said gripper actuator means including a piston and cylinder assembly connected with said gripper means and control means for activating said piston and cylinder assembly to effect operation of said gripper means between its open and closed conditions, said piston and cylinder assembly including a piston and cylinder which are movable relative to each other through a First operating stroke upon activation of said piston and cylinder assembly to effect operation of said gripper means from its open condition when a piece of bar stock is disposed within said gripper means, said piston and cylinder being movable relative to each other through a second operating stroke which is larger than said first operating stroke upon activation of said piston and cylinder assembly to effect operation of said gripper means from its open condition without a piece of bar stock disposed within said gripper means.

Claim 4

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said gripper actuator means including a piston and cylinder assembly connected with said gripper means and control means for activating said piston and cylinder assembly to effect operation of said gripper means between its open and closed conditions, said actuator means further including means for mounting said piston and cylinder assembly in a coaxial relationship with the axis about which said spindle means rotates bar stock during a machining operation, said piston and cylinder assembly including means for at least partially defining a passage through which the bar stock extends when it is being rotated by said spindle means.

Claim 5

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said gripper actuator means including a piston and cylinder assembly connected with said gripper means and control means for activating said piston and cylinder assembly to effect operation of said gripper means between its open and closed conditions, said actuator means further including means for mounting said piston and cylinder assembly in a coaxial relationship with the axis about which said spindle means rotates bar stock during a machining operation, said piston and cylinder assembly including means for at least partially defining a passage through which the bar stock extends when it is being rotated by said spindle means.

Claim 6

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said means for moving said gripper means through feed and return strokes including a drive element which is connected with said gripper means and which is movable in a first direction to effect movement of said gripper means through a feed stroke and is movable in a second direction to effect movement of said gripper mEans through a return stroke, first limit surface means for limiting motion of said drive element in the first direction, second limit surface means for limiting motion of said drive element in the second direction, and means for pressing said drive element against said first limit surface means at the end of a feed stroke and for pressing said drive element against said second limit surface means at the end of a return stroke to thereby effect movement of said gripper means through feed and return strokes of a predetermined length, said first and second limit surface means forming portions of a cam surface, said drive element including a cam follower, and said means for pressing said drive element against said first and second limit surface means including spring means for urging said cam follower into abutting engagement with said cam surface.

Claim 7

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said means for moving said gripper means through feed and return strokes including a drive element which is connected with said gripper means and which is movable in a first direction to effect movement of said gripper means through a feed stroke and is movable in a second direction to effect movement of said gripper mEans through a return stroke, first limit surface means for limiting motion of said drive element in the first direction, second limit surface means for limiting motion of said drive element in the second direction, and means for pressing said drive element against said first limit surface means at the end of a feed stroke and for pressing said drive element against said second limit surface means at the end of a return stroke to thereby effect movement of said gripper means through feed and return strokes of a predetermined length, said first and second limit surface means forming portions of a cam surface, said drive element including a cam follower, and said means for pressing said drive element against said first and second limit surface means including spring means for urging said cam follower into abutting engagement with said cam surface.

Claim 8

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said gripper means including surface means defining an opening through which the bar stock passes, said gripper actuator means being operable to vary the size of said opening from a first cross sectional area to a second cross sectional area which is smaller than said first cross sectional area upon operation of said gripper means from the open condition to the closed condition with a piece of bar stock extending through said opening, said gripper actuator means being operable to vary the size of said opening from said first cross sectional area to a third cross sectional area which is smaller than said second cross sectional area upon operation of said gripper means from the open condition to the closed condition without a piece of bar stock extending through said opening, said apparatus further including detector means for detecting a reduction in the size of said opening from said first cross sectional area to said third cross sectional area to thereby detect operation of said gripper means from the open condition to the closed condition without a piece of bar stock in said gripper means.

Claim 9

An apparatus comprising spindle means for rotating bar stock during a machining operation, said spindle means including a chuck operable between an open condition and a closed condition in which said chuck is effective to grip the bar stock and chuck actuator means for effecting operation of said chuck between the open and closed conditions, feed means for feeding bar stock to said chuck, said feed means including gripper means operable between a closed condition in which said gripper means securely grips the bar stock and an open condition in which said gripper means is ineffective to grip the bar stock, gripper actuator means for effecting operation of said gripper means between the open and closed conditions when said chuck is in the closed condition, and means for moving said gripper means through a feed stroke toward said chuck with said gripper means in its closed condition and said chuck in its open condition and for moving said gripper means through a return stroke away from said chuck with said gripper means in its open condition and said chuck in its closed condition, said gripper means including surface means defining an opening through which the bar stock passes, said gripper actuator means being operable to vary the size of said opening from a first cross sectional area to a second cross sectional area which is smaller than said first cross sectional area upon operation of said gripper means from the open condition to the closed condition with a piece of bar stock extending through said opening, said gripper actuator means being operable to vary the size of said opening from said first cross sectional area to a third cross sectional area which is smaller than said second cross sectional area upon operation of said gripper means from the open condition to the closed condition without a piece of bar stock extending through said opening, said apparatus further including detector means for detecting a reduction in the size of said opening from said first cross sectional area to said third cross sectional area to thereby detect operation of said gripper means from the open condition to the closed condition without a piece of bar stock in said gripper means.