Process for electrostatic coating of incandescent lamp envelopes

Claim 1

THE METHOD OF INTRODUCING FINELY-DIVIDED AND LIGHTSCATTERING PARTICLES THROUGH THE DIFFUSING ORIFICE OF AN ORIFICE-ELECTRODE ASSEMBLY AND INTO AN INCANDESCENT LAMP ENVELOPE HAVING AN OPEN NECK, AND COATING A SUBSTANTIAL PORTION OF SUCH INTRODUCED PARTICLES ONTO THE INTERIOR SURFACES OF THE ENVELOPE, WHICH METHOD COMPRISES: HEATING SAID ENVELOPE TO RENDER SAME SUBSTANTIALLY UNIFORMLY ELECTRICALLY CONDUCTIVE, FORMING A GAS FLOW PATH BY INSERTING SAID ORIFICE-ELECTRODE ASSEMBLY INTO THE OPEN NECK OF SAID ENVELOPE TO FORM THROUGH THE DIFFUSING ORIFICE OF SAID ASSEMBLY A PATH FOR GASEOUS MEDIUM ENTRANCE INTO SAID ENVELOPE AND TO FORM BETWEEN SAID ASSEMBLY AND THE NECK OF SAID ENVELOPE A PATH FOR GASEOUS MEDIUM RETURN FROM SAID ENVELOPE, RAPIDLY ROTATING SAID ENVELOPE WITH RESPECT TO SAID ORIFICE-ELECTRODE ASSEMBLY, FORCING THROUGH THE DIFFUSING ORIFICE OF SAID ASSEMBLY AND INTO SAID ENVELOPE A GASEOUS MEDIUM CARRYING AS A PARTICLE SMOKE AN EXCESS OF FINELY-DIVIDED AND LIGHT-SCATTERING PARTICLES OVER THAT AMOUNT DESIRED TO BE COATED WITH THE PARTICLE SMOKE BEING SUBSTANTIALLY EVENLY DIFFUSED THROUGHOUT SAID ENVELOPE AS IT IS FORCED THEREIN AND AT LEAST A PORTION OF THE PARTICLES OF THE SMOKE BEING CHARGED ON PASSING THROUGH THE ORIFICE OF SAID ASSEMBLY AND INTO SAID ENVELOPE, SIMULTANEOUSLY APPLYING A UNIDIRECTIONAL HIGH VOLTAGE BETWEEN THE ELECTRODE OF SAID ASSEMBLY AND THE WALL OF SAID ENVELOPE TO CREATE THEREBETWEEN AN ELECTROSTATIC FIELD OF SUFFICIENT MAGNITUDE TO CAUSE A SUBSTANTIAL PORTION OF THE PARTICLES INTRODUCED INTO SAID ENVELOPE TO BE ATTRACTED TO, ADHERED TO AND COATED ONTO SUBSTANTIALLY ALL OF THE INTERIOR SURFACE OF SAID ENVELOPE, AND SIMULTANEOUSLY REMOVING THE EXCESS UNCOATED FINELY-DIVIDED PARTICLES FROM SAID ENVELOPE BY MEANS OF THE GASEOUS MEDIUM RETURN FLOW FROM SAID ENVELOPE BETWEEN SAID ASSEMBLY AND THE NECK OF SAID ENVELOPE.

Claim 2

THE METHOD OF INTRODUCING FINELY-DIVIDED AND LIGHTSCATTERING PARTICLES THROUGH THE DIFFUSING ORIFICE OF AN ORIFICE-ELECTRODE ASSEMBLY AND INTO AN INCANDESCENT LAMP ENVELOPE HAVING AN OPEN NECK, AND COATING A SUBSTANTIAL PORTION OF SUCH INTRODUCED PARTICLES ONTO THE INTERIOR SURFACES OF THE ENVELOPE, WHICH METHOD COMPRISES: HEATING SAID ENVELOPE TO RENDER SAME SUBSTANTIALLY UNIFORMLY ELECTRICALLY CONDUCTIVE, FORMING A GAS FLOW PATH BY INSERTING SAID ORIFICE-ELECTRODE ASSEMBLY INTO THE OPEN NECK OF SAID ENVELOPE TO FORM THROUGH THE DIFFUSING ORIFICE OF SAID ASSEMBLY A PATH FOR GASEOUS MEDIUM ENTRANCE INTO SAID ENVELOPE AND TO FORM BETWEEN SAID ASSEMBLY AND THE NECK OF SAID ENVELOPE A PATH FOR GASEOUS MEDIUM RETURN FROM SAID ENVELOPE, RAPIDLY ROTATING SAID ENVELOPE WITH RESPECT TO SAID ORIFICE-ELECTRODE ASSEMBLY, FORCING THROUGH THE DIFFUSING ORIFICE OF SAID ASSEMBLY AND INTO SAID ENVELOPE A GASEOUS MEDIUM CARRYING AS A PARTICLE SMOKE AN EXCESS OF FINELY-DIVIDED AND LIGHT-SCATTERING PARTICLES OVER THAT AMOUNT DESIRED TO BE COATED WITH THE PARTICLE SMOKE BEING SUBSTANTIALLY EVENLY DIFFUSED THROUGHOUT SAID ENVELOPE AS IT IS FORCED THEREIN AND AT LEAST A PORTION OF THE PARTICLES OF THE SMOKE BEING CHARGED ON PASSING THROUGH THE ORIFICE OF SAID ASSEMBLY AND INTO SAID ENVELOPE, SIMULTANEOUSLY APPLYING A UNIDIRECTIONAL HIGH VOLTAGE BETWEEN THE ELECTRODE OF SAID ASSEMBLY AND THE WALL OF SAID ENVELOPE TO CREATE THEREBETWEEN AN ELECTROSTATIC FIELD OF SUFFICIENT MAGNITUDE TO CAUSE A SUBSTANTIAL PORTION OF THE PARTICLES INTRODUCED INTO SAID ENVELOPE TO BE ATTRACTED TO, ADHERED TO AND COATED ONTO SUBSTANTIALLY ALL OF THE INTERIOR SURFACE OF SAID ENVELOPE, AND SIMULTANEOUSLY REMOVING THE EXCESS UNCOATED FINELY-DIVIDED PARTICLES FROM SAID ENVELOPE BY MEANS OF THE GASEOUS MEDIUM RETURN FLOW FROM SAID ENVELOPE BETWEEN SAID ASSEMBLY AND THE NECK OF SAID ENVELOPE.