Rolling bearing with electrically insulating coating
An electrically insulated bearing ring includes a polymeric insulating coating for blocking the passage of leakage currents, the coating being formed by spraying on at least one surface of the bearing ring. The electrically insulated bearing ring or rings may be incorporated into a rolling bearing.
1 . An electrically insulated bearing ring comprising:
a bearing ring having a polymeric insulating coating configured to block the passage of electrical leakage currents, the coating being applied solely by spraying a polymeric material directly onto a corresponding surface of the bearing ring other than a raceway surface, the coating being formed of a single polymeric material or a mixture of polymeric materials to provide a single coating.
2 . The bearing ring according to claim 1 , wherein the polymeric insulating coating is formed of at least one of polyphenylene sulfide (PPS), polyetheretherketone (PEEK) and nylon (PA).
3 . The bearing ring according to claim 1 , wherein the spraying is an electrostatic spraying, a solution spraying, or a flame spraying.
4 . The bearing ring according to claim 3 , wherein when the spraying is an electrostatic spraying, polymer particles are first sprayed on the corresponding surface of the bearing ring, then heated and cured, after which the surface morphology and structural dimensions of the coating are precisely adjusted by machining.
5 . The bearing ring according to claim 4 , wherein a thickness of the polymeric insulating coating is between ten microns (10 μm) and three thousand microns (3000 μm).
6 . The bearing ring according to claim 5 , wherein the thickness of the polymeric insulating coating is between fifty microns (50 μm) and two hundred microns (200 μm).
7 . A rolling bearing comprising a bearing ring as recited in claim 1 .
8 . The rolling bearing according to claim 7 , wherein the corresponding surface is at least one of an inner circumferential surface of an inner bearing ring and an outer circumferential surface of an outer bearing ring.
9 . The rolling bearing according to claim 8 , wherein the corresponding surface further includes at least one of surfaces of shoulders on both sides of an inner ring raceway and surfaces of shoulders on both sides of an outer ring raceway.
10 . A method of forming an electrically insulated bearing ring, the method comprising the steps of:
providing an annular body, the annular body having an inner circumferential surface, an outer circumferential surface and two end surfaces, and a polymeric material; and
spraying the polymeric material directly onto at least one corresponding surface of the annular body other than a raceway surface so as to form a polymeric insulating coating configured to block the passage of leakage currents, the polymeric material being a single polymeric material or a mixture of polymeric materials to provide a single coating.
11 . The method according to claim 10 , wherein the polymeric material is formed of at least one of polyphenylene sulfide (PPS), polyetheretherketone (PEEK) and nylon (PA).
12 . The method according to claim 10 , wherein the spraying is conducted by an electrostatic spraying process, a solution spraying process, or a flame spraying process.
13 . The method according to claim 10 , wherein the spraying is conducted by an electrostatic spraying process and the method further comprises the steps of:
heating and curing the polymeric insulating coating; and
machining the coating to precisely adjust the surface morphology and dimensions of the coating.
14 . The method according to claim 10 , wherein a thickness of the polymeric insulating coating is between ten microns (10 μm) and three thousand microns (3000 μm).