# US 2023/0053751 A1 · Reciprocating unidirectional electromagnetic resistance device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0053751 A1 - Document ID: US20230053751A1 - Status: Published application - Kind: A1 - Application number: 17/408,539 - Filed: 2021-08-23 - Published: 2023-02-23 - Earliest claimed: 2021-08-23 - Inventors: YEN-CHAO LIN - Web page: https://patentgrep.com/patent/US20230053751A1 ## CPC - A63B 21/0056: {using electromagnetically-controlled friction, e.g. magnetic particle brakes} - A63B 23/03525: {Supports for both feet or both hands performing simultaneously the same movement, e.g. single pedal or single handle (A63B21/0724 takes precedence)} - A63B 21/0052: {induced by electromagnets (A63B21/0056 takes precedence)} - A63B 21/153: {wound-up and unwound during exercise, e.g. from a reel} - A63B 21/157: {Ratchet-wheel links; Overrunning clutches; One-way clutches} - A63B 21/225: {with flywheels} - A63B 24/0062: {Monitoring athletic performances, e.g. for determining the work of a user on an exercise apparatus, the completed jogging or cycling distance} - A63B 2220/35: Spin - A63B 2220/833: Sensors arranged on the exercise apparatus or sports implement - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract A reciprocating unidirectional electromagnetic resistance device includes a shaft having a flywheel installed to a first end of the shaft, an electromagnetic braking unit, and a first sensing device. A spring return device and a second sensing device are installed at a second end of the shaft, and a pull rope device is installed at the middle of the shaft. The electromagnetic braking unit and the spring return device are integrated into a single module and provided for an operator to perform a reciprocating motion to pull out a pull rope of the pull rope device and drive the shaft, the flywheel and the spring return device synchronously, and the electromagnetic braking unit acts an electromagnetic resistance onto the flywheel, so that the flywheel has the excellent precise resistance of the electromagnetic braking unit. When released, the pull rope can be retracted to achieve the reciprocating motion effect. ## Claims ### Claim 1 A reciprocating unidirectional electromagnetic resistance device, comprising: a shaft; a flywheel, having a hub rotatably coupled to the shaft, an outer ring body and the hub coaxially disposed around the periphery of the hub; and a plurality of spokes, each being coupled between the hub and the outer ring body; a one-way clutch, with an inner ring surface sheathed on a first end of the shaft, and the hub being sheathed and coupled to an outer ring surface of the one-way clutch; an electromagnetic braking unit, having a toroidal core, a plurality of serrated portions formed at an outer ring of the toroidal core, and a plurality of coils wound around the serrated portions respectively; and the electromagnetic braking unit being installed between the hub and the outer ring body of the flywheel, and the serrated portion being configured to be facing an inner ring surface of the outer ring body to produce an electromagnetic resistance; a pull rope device, having a winding wheel fixed to the shaft, and a pull rope with an end coupled to the winding wheel for pulling the winding wheel and the shaft, and the shaft and the one-way clutch driving the flywheel to rotate unidirectionally; and a spring return device, coupled to the shaft or the winding wheel, for driving the winding wheel to rewind the pulled-out pull rope. ### Claim 2 (depends on 1) The reciprocating unidirectional electromagnetic resistance device according to claim 1, further comprising a first sensing device, having a turntable coupled to an end surface of the flywheel and rotated synchronously with the flywheel; and a first sensing module configured to be facing the turntable to sense the rotating speed of the turntable. ### Claim 3 (depends on 2) The reciprocating unidirectional electromagnetic resistance device according to claim 2, further comprising a second sensing device coupled to the shaft for sensing the rotating speed of the winding wheel when the winding wheel is driven to rotate. ### Claim 4 (depends on 3) The reciprocating unidirectional electromagnetic resistance device according to claim 3, wherein the flywheel is installed at the first end of the shaft, and the spring return device is installed at a second end of the shaft, and the winding wheel of the pull rope device is sheathed and fixed between the flywheel and the shaft of the spring return device. ### Claim 5 (depends on 4) The reciprocating unidirectional electromagnetic resistance device according to claim 4, further comprising a bracket having two plates, and the shaft being rotatably passing into the two plates, so that both ends of the shaft are protruded from both sides of the bracket; and the flywheel, the electromagnetic braking unit and the first sensing device being disposed at the first end of the shaft on a first side of the bracket, and the spring return device and the second sensing device being disposed at the second end of the shaft on a second side of the bracket, and the pull rope device being disposed on the shaft between the two plates. ### Claim 6 (depends on 5) The reciprocating unidirectional electromagnetic resistance device according to claim 5, wherein the bracket has two bearing seats and two ball bearings, and the two bearing seats are coupled to two through holes of the two plates respectively, and the two ball bearings are disposed in the bearing seats respectively; and the shaft is passed and installed to the two ball bearings in the two bearing seats. ### Claim 7 (depends on 6) The reciprocating unidirectional electromagnetic resistance device according to claim 6, wherein the turntable of the first sensing device is fixed onto the hub of the flywheel and disposed adjacent to a first bearing seat of the two bearing seats, and the first sensing module is fixed onto the first bearing seat. ### Claim 8 (depends on 7) The reciprocating unidirectional electromagnetic resistance device according to claim 7, wherein the first bearing seat has a flanged ring with a plurality of screw holes; the toroidal core of the electromagnetic braking unit has a plurality of screw perforations configured to be corresponsive to the screw holes respectively, and a plurality of screws passed through the screw perforations and locked to the screw holes respectively, and the toroidal core is fixed to a side of the flanged ring. ### Claim 9 (depends on 3) The reciprocating unidirectional electromagnetic resistance device according to claim 3, wherein the winding wheel of the pull rope device is sheathed and fixed to the first end of the shaft, and the spring return device is installed to the second end of the shaft, and the flywheel is installed on the shaft between the pull rope device and the spring return device. ### Claim 10 (depends on 9) The reciprocating unidirectional electromagnetic resistance device according to claim 9, further comprising a bracket having two plates, and the shaft rotatably passing through the two plates, so that both ends of the shaft are protruded from both sides of the bracket; and the pull rope device being installed to the first end of the shaft on the first side of the bracket, and the spring return device and the second sensing device being disposed at the second end of the shaft on the second side of the bracket, and the flywheel, the electromagnetic braking unit and the first sensing device being disposed on the shaft between the two plates. ### Claim 11 (depends on 10) The reciprocating unidirectional electromagnetic resistance device according to claim 10, wherein the bracket has two bearing seats and two ball bearings, and the two bearing seats are coupled to two through holes of the two plates respectively, and the two ball bearings are disposed in the bearing seats respectively; and the shaft is passed and installed to the two ball bearings in the two bearing seats. ### Claim 12 (depends on 11) The reciprocating unidirectional electromagnetic resistance device according to claim 11, wherein the turntable of the first sensing device is fixed onto the hub of the flywheel and disposed adjacent to a first bearing seat of the two bearing seats, and the first sensing module is fixed onto the first bearing seat. ### Claim 13 (depends on 12) The reciprocating unidirectional electromagnetic resistance device according to claim 12, wherein the first bearing seat has a flanged ring with a plurality of screw holes; the toroidal core of the electromagnetic braking unit has a plurality of screw perforations configured to be corresponsive to the screw holes respectively, and a plurality of screws passed through the screw perforations and locked to the screw holes respectively, and the toroidal core is fixed to a side of the flanged ring. ### Claim 14 (depends on 3) The reciprocating unidirectional electromagnetic resistance device according to claim 3, wherein the spring return device has a shell and a scroll spring installed in the shell and disposed around the shaft, and the scroll spring has an inner end fixed to the shaft and an outer end fixed to the shell. ### Claim 15 (depends on 14) The reciprocating unidirectional electromagnetic resistance device according to claim 14, wherein the second sensing device comprises a sensed element and a second sensing module, and the sensed element is fixed to an end surface of the shaft, and the second sensing module is fixed to the shell, and the second sensing module is configured to be facing the sensed element to sense the rotating speed of the sensed element and the shaft. ### Claim 16 (depends on 1) The reciprocating unidirectional electromagnetic resistance device according to claim 1, further comprising a second sensing device coupled to the shaft for sensing the rotating speed of the winding wheel when the winding wheel is driven to rotate. ### Claim 17 (depends on 16) The reciprocating unidirectional electromagnetic resistance device according to claim 16, further comprising a bracket having two plates, and the shaft being rotatably passing into the two plates, so that both ends of the shaft are protruded from both sides of the bracket; and the flywheel and the electromagnetic braking unit being disposed at the first end of the shaft on a first side of the bracket, and the spring return device and the second sensing device being disposed at the second end of the shaft on a second side of the bracket, and the pull rope device being disposed on the shaft between the two plates. ### Claim 18 (depends on 17) The reciprocating unidirectional electromagnetic resistance device according to claim 17, wherein the second sensing device comprises a sensed element and a second sensing module, and the sensed element is fixed to an end surface of the shaft, and the second sensing module is fixed to the spring return device, and the second sensing module is configured to be facing the sensed element to sense the rotating speed of the sensed element and the shaft. ### Claim 19 (depends on 16) The reciprocating unidirectional electromagnetic resistance device according to claim 16, further comprising a bracket having two plates, and the shaft rotatably passing through the two plates, so that both ends of the shaft are protruded from both sides of the bracket; and the pull rope device being installed to the first end of the shaft on the first side of the bracket, and the spring return device and the second sensing device being disposed at the second end of the shaft on the second side of the bracket, and the flywheel and the electromagnetic braking unit being disposed on the shaft between the two plates. ### Claim 20 (depends on 19) The reciprocating unidirectional electromagnetic resistance device according to claim 19, wherein the second sensing device comprises a sensed element and a second sensing module, and the sensed element is fixed to an end surface of the shaft, and the second sensing module is fixed to the spring return device, and the second sensing module is configured to be facing the sensed element to sense the rotating speed of the sensed element and the shaft.