# US 8,783,723 B2 · Safety belt system and belt winder > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,723 B2 - Document ID: US8783723B2 - Status: Granted - Kind: B2 - Application number: 13/745,538 - Filed: 2013-01-18 - Published: 2013-07-25 - Granted: 2014-07-22 - Earliest claimed: 2012-01-20 - Assignees: Johnson Electric S.A. - Applicants: Johnson Electric S.A. - Inventors: Hang Fung Chang; Hang Cheong Ma; Daniel Ming Hong Wong - Web page: https://patentgrep.com/patent/US8783723B2 ## CPC - B60R 22/46: {Reels} with means to tension the belt in an emergency {by forced winding up}(electrical circuits for triggering safety arrangements B60R21/01 {; tensioners using reels only guiding the belt during normal use, e.g. splitted reels B60R22/195}) - H02K 23/30: having lap or loop windings - H02K 23/36: having two or more windings; having two or more commutators; having two or more stators - B60R 2022/4666: {characterised by electric actuators} - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract A belt winder for a safety belt system includes a belt reel for tightening or loosing the safety belt, and an electric motor for driving the belt reel. The motor includes a stator and a rotor rotatably mounted to the stator. The rotor includes an motor shaft, a commutator fixed to the motor shaft, a rotor core fixed to the motor shaft and rotor windings wound about teeth of the rotor core and electrically connected to segments of the commutator. The rotor windings include a plurality of winding units. Each winding unit includes at least two coils, the coils of each winding unit being wound about the same teeth and electrically connected to a same pair of segments in parallel. A safety belt system incorporating the belt winder is also provided. ## Claims ### Claim 1 A safety belt system comprising: a safety belt for restraining an occupant in a seat; a tongue plate arranged on the safety belt; a buckle detachably engaged with the tongue plate; a belt reel for tightening or loosing the safety belt; an electric motor for driving the belt reel, the motor comprising: a stator; and a rotor rotatably mounted to the stator, the rotor comprising a motor shaft, a commutator fixed to the motor shaft, a rotor core fixed to the motor shaft and rotor windings wound about teeth of the rotor core and electrically connected to segments of the commutator, the rotor windings comprises a plurality of winding units, each winding unit comprising at least two coils, the coils of each winding unit being wound about the same teeth and electrically connected to a same pair of segments, in parallel; a detection unit for detecting whether a predefined event is happening or is imminent; and a controller for controlling the motor based on the detecting result of the detection unit, wherein the rotor windings are arranged in two layers, an inner layer and an outer layer, each winding unit comprises two coils, one of the two coils being arranged in the inner layer, the other one of the two coils being arranged in the outer layer. ### Claim 2 (depends on 1) The safety belt system of claim 1, wherein the rotor windings are wound by one continuous wire. ### Claim 3 (depends on 1) The safety belt system of claim 1, wherein a part of the inner layer coils and a part of the outer layer coils are wound by one continuous wire, and the other part of the inner layer coils and the other part of the outer layer coils are wound by another continuous wire. ### Claim 4 (depends on 1) The safety belt system of claim 1, wherein at least one dummy slot is formed in a circumferential surface of each tooth of the rotor core. ### Claim 5 (depends on 1) The safety belt system of claim 1, wherein the rotor core comprises five teeth, and each tooth comprises two dummy slots formed in a circumferential surface of the tooth. ### Claim 6 (depends on 1) The safety belt system of claim 1, further comprising a pretensioner coupled to a central shaft of the belt reel. ### Claim 7 (depends on 1) The safety belt system of claim 1, wherein the stator has two magnetic poles, the rotor core has five teeth, and the commutator has five segments. ### Claim 8 A safety belt system comprising: a safety belt for restraining an occupant in a seat; a tongue plate arranged on the safety belt; a buckle detachably engaged with the tongue plate; a belt reel for tightening or loosing the safety belt; an electric motor for driving the belt reel, the motor comprising: a stator; and a rotor rotatably mounted to the stator, the rotor comprising an motor shaft, a commutator fixed to the motor shaft, a rotor core fixed to the motor shaft and rotor windings wound about teeth of the rotor core and electrically connected to segments of the commutator, the rotor windings comprises a plurality of winding units, each winding unit comprising at least two coils, the coils of each winding unit being wound about the same teeth and electrically connected to a same pair of segments, in parallel; a detection unit for detecting whether a predefined event is happening or is imminent; a controller for controlling the motor based on the detecting result of the detection unit; and a transmission unit coupled between the motor shaft and a central shaft of the belt reel, the motor driving the belt reel via the transmission unit. ### Claim 9 (depends on 8) The safety belt system of claim 8, further comprising a pretensioner coupled to a first end of the central shaft of the belt reel, wherein the transmission unit is coupled between the motor shaft and a second end of the central shaft. ### Claim 10 A belt winder for a safety belt system comprising: a belt reel for tightening or loosing the safety belt; an electric motor for driving the belt reel, the motor comprising a stator and a rotor rotatably mounted to the stator, the rotor comprising an motor shaft, a commutator fixed to the motor shaft, a rotor core fixed to the motor shaft and rotor windings wound about teeth of the rotor core and electrically connected to segments of the commutator, the rotor windings comprises a plurality of winding units, each winding unit comprising at least two coils, the coils of each winding unit being wound about the same teeth and electrically connected to a same pair of segments, in parallel; and a transmission unit coupled between the motor shaft and a central shaft of the belt reel, the motor driving the belt reel via the transmission unit. ### Claim 11 (depends on 10) The belt winder of claim 10, wherein the rotor windings are arranged in two layers, an inner layer and an outer layer, each winding unit comprises two coils, one of the two coils being arranged in the inner layer, the other one of the two coils being arranged in the outer layer. ### Claim 12 (depends on 11) The belt winder of claim 11, wherein the rotor windings are wound by one continuous wire. ### Claim 13 (depends on 11) The belt winder of claim 11, wherein a part of the inner layer coils and a part of the outer layer coils are wound by one continuous wire, and the other part of the inner layer coils and the other part of the outer layer coils are wound by another continuous wire. ### Claim 14 (depends on 10) The belt winder of claim 10, wherein at least one dummy slot is formed in a circumferential surface of each tooth of the rotor core. ### Claim 15 (depends on 10) The belt winder of claim 10, wherein the rotor core comprises five teeth, and each tooth comprises two dummy slots formed in a circumferential surface of the tooth. ### Claim 16 (depends on 10) The belt winder of claim 10, further comprising a pretensioner coupled to a central shaft of the belt reel. ### Claim 17 (depends on 10) The belt winder of claim 10, further comprising a pretensioner coupled to a first end of a central shaft of the belt reel, wherein the transmission unit is coupled between the motor shaft and a second end of the central shaft. ### Claim 18 (depends on 10) The belt winder of claim 10, wherein the stator has two magnetic poles, the rotor core has five teeth, and the commutator has five segments.