Lapping machine

Claim 2

A lapping machine for finishing a surface in a workpiece by means of a linearly reciprocating, non-rotating lapping tool comprising: a frame; a secondary slide member slidably mounted in the lapping machine for linear reciprocation movement with respect to the frame in a direction toward and away from the workpiece, said secondary slide member including means for mounting the lapping tool thereon such that reciprocation of the secondary slide member brings the lapping tool into abrading engagement with the surface of the workpiece; drive means mounted on the frame for reciprocating the secondary slide member so as to move the lapping tool into and out of abrading engagement with the surface of the workpiece, said drive means being connected to the secondary slide member by means of a resilient biasing means, said resilient biasing means urging the lapping tool into engagement with the workpiece in response to moVement by the drive means toward the workpiece, said resilient biasing means urging the lapping tool against the surface of the workpiece with a pressure that increases in proportion to the amount of relative movement between the secondary slide member and the drive means when the drive means is moved toward the workpiece; sensor means for sensing the relative movement of the drive means and secondary slide member in the direction toward the workpiece, said sensor means generating a control signal when the distance moved by the drive means exceeds the distance moved by the secondary slide member by a predetermined amount; and control means for reversing the direction of the drive means so as to withdraw the lapping tool from the workpiece whenever said control signal is generated, said control means thereafter causing the drive means to commence another reciprocation toward the workpiece.

Claim 3

An improvement as claimed in claim 1 wherein the electronic control means comprise manually adjustable speed control means to control independently the speed at which the lapping tool is moved in said forward and reverse directions.

Claim 4

An improvement as claimed in claim 1 wherein the electronic control means further comprises manually adjustable up time control means to control independently the amount of time the lapping tool is moved in said reverse direction before commencement of another reciprocation in a forward direction.

Claim 5

An improvement as claimed in claim 3 wherein the electronic control means further comprises manually adjustable down time control means to control independently the amount of time the lapping tool is moved in said forward direction before movement is reversed to a reverse direction.

Claim 6

An improvement as claimed in claim 4 wherein the up time control means is adapted to cause forward movement of the lapping tool and the actuation of the down time control means when the predetermined up time elapses, and the down time control means is adapted to cause reverse movement of the lapping tool and the actuation of the up time control means when the predetermined down time elapses.

Claim 7

An improvement as claimed in claim 5 and further comprising switch means for selective disengagement of the down time control means so as to prevent the down time control means from causing reverse movement of the lapping tool and actuation of the up time control means when the predetermined down time elapses.

Claim 8

An improvement as claimed in claim 6 and further comprising limit switch means adapted to override the up and down controls and cause the movement of the lapping tool in a reverse direction out of contact with the workpiece after the lapping tool has moved a predetermined distance in said forward direction relative to the workpiece, said limit switch means being further adapted to turn off the lapping machine automatically after the lapping tool has moved a predetermined distance in said reverse direction.

Claim 9

An improvement as claimed in claim 1 wherein the sensor means is adjustable to adjust the pressure at which the sensor means triggers the withdrawal of the lapping tool from the workpiece.

Claim 10

A lapping machine according to claim 1 wherein the sensor means comprises: photocell means mounted for movement in response to the movement of either the drive means or the secondary slide member, said photocell means generating said control signal when actuated; photocell actuating means mounted for movement in response to the movement of the other of the drive means or the secondary slide member, whichever the movement of the photocell means is not responsive to, said photocell means actuating the photocell means whenever the forward movement of the drive means exceeds the forward movement of the secondary slide member by said predetermined amount.

Claim 11

A lapping machine according to claim 1 wherein: the photocell means comprises a photocell and light source mounted in fixed positions relative to each other, with the light sourCe positioned such that it directs light on the photocell when the photocell is not actuated, the control signal from the photocell being produced by the interruption of the light directed on the photocell by the light source; and the photocell actuating means is a flag mounted such that the flag moves relative to the photocell and light source and interrups the light directed on the photocell by the light source when the forward movement of the drive means exceeds the forward movement of the secondary slide member by said predetermined amount.

Claim 12

A lapping machine according to claim 10 wherein: the drive means comprises a hydraulic cylinder mounted on the frame and having an extendible drive shaft protruding therefrom; the control means are electronically operated and include electro-hydraulic servo valve means for controlling the operation of the hydraulic cylinder; a primary slide is mounted for linear motion along the frame and is drivingly attached to the extendible drive shaft; the resilient biasing means interconnects the primary and secondary slides; the light source and photocell are mounted for movement with the primary slide; and the flag is mounted for movement with the secondary slide.

Claim 13

A lapping machine as claimed in claim 11 wherein the secondary slide is slidably mounted on the primary slide, and the primary slide is slidably mounted on the frame.

Claim 14

A lapping machine for surfacing a surface in a workpiece with a lapping tool comprising: a frame; a primary slide member mounted for slidable movement along a linear path in forward and reverse directions with respect to the frame; a secondary slide member mounted for slidable movement along a linear path in said forward and reverse directions with respect to the frame, said secondary slide member including means for mounting the lapping tool such that the lapping tool will contact the surface of the workpiece upon movement of the secondary slide member in its forward direction; resilient biasing means interconnecting the primary and secondary slide members, said biasing means urging the secondary slide member to travel along its path in the forward direction in response to the movement of the primary slide in the forward direction; return means for moving the secondary slide member in the reverse direction in response to movement of the primary slide member in the reverse direction; drive means for moving the primary slide member in either direction on its linear path, said drive means comprising a double-action hydraulic cylinder; and control means for controlling the operation of the drive means so as to produce reciprocal motion of the primary slide member and cause a resultant reciprocation of the secondary slide member, said control means comprising: electro-hydraulic servo valve means for controlling the operation of the hydraulic cylinder in response to electronic controls; sensor means for causing the drive means to reverse the direction of movement of the primary slide from the forward direction to the reverse direction whenever the distance moved by the primary slide in the forward direction exceeds the distance moved by the secondary slide in the forward dirrection by a predetermined amount, the relative forward movement of the primary and secondary slide members through said predetermined distance being sensed by photocell means mounted in the lapping machine for movement responsive to the movement of one slide, said photocell means being actuated to trigger withdrawal of the lapping tool from the workpiece by photocell actuating means mounted for movement in response to the movement of the other slide, said photocell means and photocell actuating means being positioned so that the photocell actuating means actuates the photocell after said predetermined relative movement between the slides; means for causing the drive means to re-reverse the direction of the primary slide member after predeternined movEment of the primary slide member in the reverse direction; and electronic control means for controlling independently the forward and reverse speeds of the lapping tool and the amount of time the lapping tool moves in its reverse direction before movement is switched to the forward direction, said control means being manually adjustabe to vary separately forward speed, reverse speed, and reverse time.

Claim 15

A lapping machine for surfacing a surface in a workpiece with a lapping tool comprising: a frame; a primary slide member mounted for slidable movement along a linear path in forward and reverse directions with respect to the frame; a secondary slide member mounted for slidable movement along a linear path in said forward and reverse directions with respect to the frame, said secondary slide member including means for mounting the lapping tool such that the lapping tool will contact the surface of the workpiece upon movement of the secondary slide member in its forward direction; resilient biasing means interconnecting the primary and secondary slide members, said biasing means urging the secondary slide member to travel along its path in the forward direction in response to the movement of the primary slide in the forward direction; return means for moving the secondary slide member in the reverse direction in response to movement of the primary slide member in the reverse direction; drive means for moving the primary slide member in either direction on its linear path, said drive means comprising a double-action hydraulic cylinder; and control means for controlling the operation of the drive means so as to produce reciprocal motion of the primary slide member and cause a resultant reciprocation of the secondary slide member, said control means comprising: electro-hydraulic servo valve means for controlling the operation of the hydraulic cylinder in response to electronic controls; sensor means for causing the drive means to reverse the direction of movement of the primary slide from the forward direction to the reverse direction whenever the distance moved by the primary slide in the forward direction exceeds the distance moved by the secondary slide in the forward dirrection by a predetermined amount, the relative forward movement of the primary and secondary slide members through said predetermined distance being sensed by photocell means mounted in the lapping machine for movement responsive to the movement of one slide, said photocell means being actuated to trigger withdrawal of the lapping tool from the workpiece by photocell actuating means mounted for movement in response to the movement of the other slide, said photocell means and photocell actuating means being positioned so that the photocell actuating means actuates the photocell after said predetermined relative movement between the slides; means for causing the drive means to re-reverse the direction of the primary slide member after predeternined movEment of the primary slide member in the reverse direction; and electronic control means for controlling independently the forward and reverse speeds of the lapping tool and the amount of time the lapping tool moves in its reverse direction before movement is switched to the forward direction, said control means being manually adjustabe to vary separately forward speed, reverse speed, and reverse time.

Claim 16

A lapping machine as claimed in claim 13 wherein the control means further comprises: manually adjustable forward time control means for controlling the amount of time the lapping tool is permitted to move in a forward direction before the movement is switched to a reverse direction, if the movement is not otherwise reversed by the control means or sensor.

Claim 17

A lapping machine as claimed in claim 14 and further comprising limit switch means adapted to reverse the movement of the lapping tool to the reverse direction after the lapping tool has proceeded a predetermined distance through the workpiece and thereafter turn off the lapping machine after the lapping tool has been moved for a predetermined distance in the reverse direction.

Claim 18

A lapping machine according to claim 13 wherein the primary slide is slidably mounted on the frame for linear movement in said forward and reverse direction and the secondary slide is slidably mounted on the primary slide for linear movement in said forward and reverse directions with respect to the frame and the primary slide.

Claim 19

A lapping machine according to claim 16 wherein the secondary slide is mounted on the primary slide by means of a dovetail protrusion on the secondary slide member and a mating dovetail slot in the primary slide, in which the dovetail protrusion rides.

Claim 20

A lapping machine according to claim 16 wherein the resiliency of the resilient biasing means is adjustable so as to vary the pressure required on the lapping tool before the sensor means triggers the withdrawal of the lapping tool from the workpiece.

Claim 21

A lapping machine according to claim 18 wherein the resilient biasing means is a compression spring interconnecting the primary and secondary slide members, the resiliency adjustment in said resilient biasing means comprising adjustment means for varying the length of the spring so as to apply a variable initial compression load on the spring, such adjustment serving to change the lapping tool pressure necessary to cause said predetermined relative movement between the primary and secondary slide members.