# US 2019/0168893 A1 · Reaction wheel apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0168893 A1 - Document ID: US20190168893A1 - Status: Published application - Kind: A1 - Application number: 16/321,372 - Filed: 2017-07-24 - Published: 2019-06-06 - Earliest claimed: 2016-07-29 - Assignees: Japan Aerospace Exploration Agency - Applicants: Japan Aerospace Exploration Agency - Inventors: Shinji MITANI; Shuhei SHIGETO - Web page: https://patentgrep.com/patent/US20190168893A1 ## CPC - B64G 1/283: {using reaction wheels} - B64G 1/244: {Spacecraft control systems} - B64G 1/28: using inertia or gyro effect - G01P 3/487: delivered by rotating magnets - H02K 5/00: Casings; Enclosures; Supports - H02K 5/04: Casings or enclosures characterised by the shape, form or construction thereof - H02K 7/02: Additional mass for increasing inertia, e.g. flywheels - H02K 11/30: Structural association with control circuits or drive circuits - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - Y02E 60/16: Mechanical energy storage, e.g. flywheels or pressurised fluids - B64G: COSMONAUTICS; VEHICLES OR EQUIPMENT THEREFOR - 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}) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A reaction wheel apparatus including a reaction wheel provided in a polyhedral housing, in which respective faces constituting a polyhedron are constituted by frame parts corresponding to the respective faces constituting the polyhedron, and at least two of the frame parts are constituted by at least two rigid circuit board parts of a rigid flexible substrate. ## Claims ### Claim 1 A reaction wheel apparatus including a reaction wheel provided in a polyhedral housing, wherein respective faces constituting a polyhedron are constituted by frame parts corresponding to the respective faces constituting the polyhedron, and at least two of the frame parts are constituted by at least two rigid circuit board parts of a rigid flexible substrate. ### Claim 2 (depends on 1) The reaction wheel apparatus according to claim 1, wherein the rigid flexible substrate includes a first rigid circuit board part, the first rigid circuit board part of the rigid flexible substrate has a first through opening penetrating in the thickness direction of the first rigid circuit board part, the first through opening has a nut accommodation part extending substantially parallel to a side edge of the first rigid circuit board part and a screw accommodation part that opens to the side edge of the first rigid circuit board part and extends orthogonally to the nut accommodation part, a nut is accommodated in the nut accommodation part, at least one first frame part neighboring the first rigid circuit board part has a through hole at a position aligned with the screw accommodation part of the first through opening of the first rigid circuit board part and the nut accommodated in the nut accommodation part, and the at least one first rigid circuit board part and the first frame part are connected by driving the screw inserted from the outside of the at least one first frame part into the nut through the through hole and the screw accommodation part. ### Claim 3 (depends on 1) The reaction wheel apparatus according to claim 1, wherein a cutout part opening outward is formed at a side edge of at least one rigid circuit board part of the rigid flexible substrate, a frame part connected to the side edge formed with the cutout part is disposed so as to cover an opening edge of the cutout part, in such a way as to form an opening between the frame part connected to the side edge formed with the cutout part and the cutout part, and a wiring from a component provided inside the housing is connected to a terminal provided on an outer surface of the at least one rigid circuit board part, through the opening. ### Claim 4 (depends on 1) The reaction wheel apparatus according to claim 1, wherein a stepped cutout part opening outward is formed at least one side edge of the rigid flexible substrate where a flexible cable is connected, of at least one rigid circuit board part of the rigid flexible substrate, and the flexible cable extends from a deeper part of the stepped cutout part. ### Claim 5 (depends on 1) The reaction wheel apparatus according to claim 1, wherein a connection assist member to which an external device can be connected is attached to at least one vertex part or side region of the polyhedron. ### Claim 6 (depends on 1) The reaction wheel apparatus according to claim 1, wherein the reaction wheel is provided so as to face the frame part. ### Claim 7 (depends on 6) The reaction wheel apparatus according to claim 6, wherein the reaction wheel is provided so as to face a frame part other than the frame part constituted by the rigid flexible substrate. ### Claim 8 (depends on 1) The reaction wheel apparatus according to claim 1, wherein the reaction wheel includes a rotary body disposed so as to face the frame part, an electromagnet disposed between the frame part and the rotary body, and an urging member attached to the frame part and urging the electromagnet toward the frame part, wherein at least a partial portion of the rotary body facing the electromagnet is formed of a ferromagnetic material, the electromagnet is urged by the urging member in such a manner that the electromagnet and the rotary body are separated from each other when the electromagnet is not energized, and the electromagnet comes into contact with the rotary body against an urging force of the urging member when the electromagnet is energized, thereby braking the rotary body. ### Claim 9 (depends on 8) The reaction wheel apparatus according to claim 8, wherein a motor for rotating the rotary body is disposed between the rotary body and the frame part, and a wiring from the motor is drawn out between the urging member and the frame part. ### Claim 10 (depends on 1) The reaction wheel apparatus according to claim 1, wherein the polyhedron is a hexahedron. ### Claim 11 (depends on 3) The reaction wheel apparatus according to claim 3, wherein the component provided inside the housing is an electromagnet of the reaction wheel.