# US 2013/0278118 A1 · Impulse ring for a bearing assembly, bearing assembly comprising such an impulse ring and rotary electrical machine comprising such a bearing assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0278118 A1 - Document ID: US20130278118A1 - Status: Published application - Kind: A1 - Application number: 13/880,106 - Filed: 2010-10-18 - Published: 2013-10-24 - Earliest claimed: 2010-10-18 - Inventors: Pierrick Maze; Sylvain Chaussat - Web page: https://patentgrep.com/patent/US20130278118A1 ## CPC - G01B 7/30: for measuring angles or tapers; for testing the alignment of axes - F16C 41/007: {Encoders, e.g. parts with a plurality of alternating magnetic poles} - G01P 3/443: {mounted in bearings (bearings F16C)} - H02K 11/215: Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements - F16C 19/06: with a single row or balls - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract This impulse ring (2) for a bearing assembly comprising a rotative element on which the impulse ring (2) is mounted, is rotatable with respect to a fixed sensing element adapted to detect a magnetic field generated by the impulse ring (2). The impulse ring (2) comprises at least one pair of magnetic poles (N, S) or at least one magnet (4) with north poles (N) and south poles (S) alternatively arranged along its circumference. The intensity of the magnetic field generated by the north poles (N) is different from the intensity of the magnetic field generated by the south poles (S). ## Claims ### Claim 1 An impulse ring (2) for a bearing assembly comprising: a rotative element on which the impulse ring is mounted, rotatable with respect to a fixed sensing element adapted to detect a magnetic field (Br) generated by the impulse ring, the impulse ring having at least one pair of magnetic poles (N, S) or at least one magnet with north poles (N) and south poles (S) alternatively arranged along the circumference of the impulse ring, wherein the intensity of the magnetic field (Bnp) generated by the north poles (N) is different from the intensity of the magnetic field (Bsp) generated by the south poles (S). ### Claim 2 (depends on 1) The impulse ring according to claim 1, wherein all the north poles (N) have the same volume, wherein all the south poles (S) have the same volume, and wherein the north poles (N) and the south poles (S) have different volumes. ### Claim 3 (depends on 1) The impulse ring according to claim 1, wherein the north poles (N) and south poles (S) cover angular sectors having different apex angles. ### Claim 4 (depends on 1) The impulse ring according to claim 1, wherein the north poles (N) and south poles (S) have different thicknesses (t1, t2) with respect to a radial direction (Y-Y′) of the impulse ring (2). ### Claim 5 (depends on 1) The impulse ring according to claim 1, wherein the north poles (N) and the south poles (S) have different widths, with respect to a direction parallel to the rotation axis (X-X′) of the impulse ring. ### Claim 6 (depends on 1) The impulse ring according to claim 1, wherein the north poles (N) and the south poles (S) are realized in different materials. ### Claim 7 (depends on 1) The impulse ring according to claim 1, wherein the magnetic properties of the materials in which the north poles (N) and the south poles (S) are realized are altered. ### Claim 8 (depends on 1) The impulse ring according to claim 1, wherein the north poles (N) and south poles (S) are covered with absorber varnish layers of different respective thicknesses and/or different respective magnetic properties. ### Claim 9 (depends on 1) The impulse ring according to claim 1, further comprising a magnetic frame having casings in which the pairs of poles (N, S) or the magnets are arranged, and wherein the casings have different influences on the magnetic fields (Bnp, Bsp) generated by the north poles (N) and south poles (S). ### Claim 10 (depends on 1) The impulse ring according to claim 1, further comprising an amagnetic frame comprising casings in which the pairs of poles (N, S) or the magnets are arranged. ### Claim 11 (depends on 9) The impulse ring according to claim 9, wherein south poles (S) or north poles (N) are arranged in open casings. ### Claim 12 A bearing assembly (A) comprising: a rotatable ring, a non-rotatable ring and an impulse ring having: a rotative element on which the impulse ring is mounted, rotatable with respect to a fixed sensing element adapted to detect a magnetic field (Br) generated by the impulse ring, the impulse ring having at least one pair of magnetic poles (N, S) or at least one magnet with north poles (N) and south poles (S) alternatively arranged along the circumference of the impulse ring, wherein the intensity of the magnetic field (Bnp) generated by the north poles (N) is different from the intensity of the magnetic field (Bsp) generated by the south poles (S). ### Claim 13 (depends on 12) The bearing assembly according to claim 12, further comprising a sensor adapted to read the impulse ring. ### Claim 14 (depends on 13) The bearing assembly according to claim 13, wherein the sensor is mounted on the non-rotatable ring or on a part rotatably fastened with the non-rotatable ring. ### Claim 15 A rotary electrical machine (EM) such as a motor and/or a generator, self-generating or being immersed, in operation, in a disturbing magnetic field (Bd), and comprising: a stator (22), a rotor (12), a bearing assembly (A) having a rotatable ring, a non-rotatable ring and an impulse ring having; a rotative element on which the impulse ring is mounted, rotatable with respect to a fixed sensing element adapted to detect a magnetic field (Br) generated by the impulse ring, the impulse ring having at least one pair of magnetic poles (N, S) or at least one magnet with north poles (N) and south poles (S) alternatively arranged along the circumference of the impulse ring, wherein the intensity of the magnetic field (Bnp) generated by the north poles (N) is different from the intensity of the magnetic field (Bsp) generated by the south poles (S), and a sensor for reading the impulse ring, wherein the bearing assembly (A) supports the rotor with respect to the stator and wherein the sensor delivers a signal for controlling the rotation of the rotor. ### Claim 16 A rotary electrical machine (EM) such as a motor and/or a generator, self-generating or being immersed, in operation, in a disturbing magnetic field (Bd), and comprising: a stator (22), a rotor (12), and a bearing assembly (A) having a sensor adapted to read the impulse ring, wherein the bearing assembly (A) supports the rotor with respect to the stator and wherein the sensor delivers a signal for controlling the rotation of the rotor.