Cutting instrument improvement for X-Y plotter

A display material cutting assembly for use with a computer controlled X-Y plotter of the type including means for detachably receiving and controlling a laminated sheet including a layer of display material adhered to a layer of release material, an instrument carrying member having means for detachably receiving and holding an instrument thereon in fixed centered relation, a carriage having means for mounting said instrument carrying member thereon (1) for biased movement into an operative position wherein an instrument received and held in fixed centered relation by said instrument receiving and holding means is disposed in operative relation with a laminated sheet received and controlled by said laminated sheet receiving and controlling means and (2) for controlled movement from said operative position against the bias thereof into an inoperative position wherein an instrument received and held by said instrument receiving and holding means is disposed in spaced relation with a laminated sheet received and controlled by said laminated sheet receiving and controlling means, and means for mounting said laminated sheet receiving and controlling means and said carriage for relative movements with respect to each other such that relative movements along both an X axis and a Y axis can be effected between an instrument received and held in fixed centered relation by said instrument receiving and holding means and a laminated sheet received and controlled by said sheet receiving and controlling means with the instrument carrying member either in an operative or inoperative position, said display material cutting mechanism comprising

• an electric motor having a housing,
• a rotor mounted in said housing for rotation about an axis fixed with respect to said housing at a relatively high speed in response to the connection of said motor with a source of electric current,
• means on said motor housing for cooperating with the instrument receiving and holding means to enable the latter to hold said motor housing in fixed centered relation on said instrument carrying member for controlled movement with said instrument carrying member into said inoperative position and biased movement with said instrument carrying member into said operative position,
• a cutting tool detachably fixed to said rotor for rotation therewith and having a sharp point disposed on said rotational axis when said instrument carrying member is in said operative position for relative X and Y axis movements with respect to a laminated sheet received and controlled by said laminated sheet receiving and controlling means, and
• a support having means for fixedly securing the same to said carriage,
• adjustable spring means acting between said motor housing and said support for resiliently supporting a selected portion of the weight of said electric motor and cutting tool on said carriage without preventing said electric motor and cutting tool from controlled movement with said instrument carrying member into said inoperative position and biased movement with said instrument carrying member into said operative position so as to enable said cutting tool to cut the layer of display material during relative X and Y axis movements without severing the layer of release material.

In a computer controlled X-Y plotter including means for detachably receiving and controlling a sheet-like workpiece, an instrument carrying member having means for detachably receiving and holding an instrument thereon in fixed centered relation, a carriage having means for mounting said instrument carrying member thereon (1) for biased movement into an operative position wherein an instrument received and held in fixed centered relation by said instrument receiving and holding means is disposed in operative relation with a sheet-like workpiece received and controlled by said workpiece receiving and controlling means and (2) for controlled movement from said operative position against the bias thereof into an inoperative position wherein an instrument received and held by said instrument receiving and holding means is disposed in spaced relation with a sheet-like workpiece received and controlled by said workpiece receiving and controlling means, and means for mounting said workpiece receiving and controlling means and said carriage for relative movements with respect to each other such that relative movements along both an X axis and a Y axis can be effected between an instrument received and held in fixed centered relation by said instrument receiving and holding means and a sheet-like workpiece received and controlled by said workpiece receiving and controlling means with the instrument carrying member either in an operative or inoperative position, the improvement which comprises

• an electric motor having a housing,
• a rotor mounted in said housing for rotation about an axis fixed with respect to said housing at a relatively high speed in response to the connection of said motor with a source of electric current,
• means on said motor housing for cooperating with said instrument receiving and holding means to enable the latter to hold said motor housing in fixed centered relation on said instrument carrying member for controlled movement with said instrument carrying member into said inoperative position and biased movement with said instrument carrying member into said operative position,
• said rotor including chuck means for detachably receiving a cutting tool for rotation therewith about said rotational axis when said instrument carrying member is in said operative position for relative X and Y axis movements with respect to a workpiece received and controlled by said laminated sheet receiving and controlling means, and
• adjustable spring means acting between said motor housing and said carriage for resiliently supporting said electric motor on said carriage in such a way as to (1) accommodate the controlled movement of said electric motor with said instrument carrying member into said inoperative position and (2) facilitate the biased movement of said electric motor with said instrument carrying member into said operative position,
• said adjustable spring means including opposed springs biasing said electric motor in opposite directions and means for varying the net biasing effect of said opposed springs so as to enable the biased movement of said electric motor with said instrument carrying member into said operative position to maintain the desired depth of cut of the workpiece for the cutting tool mounted in said chuck means.

A sheet-like workpiece cutting assembly for use with a computer controlled X-Y plotter of the type including means for detachably receiving and controlling a sheet-like workpiece, an instrument carrying member having means for detachably receiving and holding an instrument thereon in fixed centered relation, a carriage having means for mounting said instrument carrying member thereon (1) for biased movement into an operative position wherein an instrument received and held in fixed centered relation by said instrument receiving and holding means is disposed in operative relation with a sheet-like workpiece received and controlled by said sheet-like workpiece receiving and controlling means and (2) for controlled movement from said operative position against the bias thereof into an inoperative position wherein an instrument received and held by said instrument receiving and holding means is disposed in spaced relation with a sheet-like workpiece received and controlled by said workpiece receiving and controlling means, and means for mounting said workpiece receiving and controlling means and said carriage for relative movements with respect to each other such that relative movements along both an X axis and a Y axis can be effected between an instrument received and held in fixed centered relation by said instrument receiving and holding means and a sheet-like workpiece received and controlled by said workpiece receiving and controlling means with the instrument carrying member either in an operative or inoperative position, said sheet-like workpiece cutting mechanism comprising

• an electric motor having a housing,
• a rotor mounted in said housing for rotation about an axis fixed with respect to said housing at a relatively high speed in response to the carrying member into said inoperative position and biased movement with said instrument carrying member into said operative position,
• a cutting tool detachably fixed to said rotor for rotation therewith and having a sharp point disposed on said rotational axis when said instrument carrying member is in said operative position for relative X and Y axis movements with respect to a laminated sheet received and controlled by said laminated sheet receiving and controlling means, and
• a support having means for fixedly securing the same to said carriage,
• adjustable spring means acting between said motor housing and said support for resiliently supporting a selected portion of the weight of said electric motor and cutting tool on said carriage without preventing said electric motor and cutting tool from controlled movement with said instrument carrying member into said inoperative position and biased movement with said instrument carrying member into said operative position so as to enable said cutting tool to cut the layer of display material during relative X and Y axis movements without severing the layer of release material.