# US 10,480,597 B2 · Clutch apparatus and method for controlling the clutch apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,480,597 B2 - Document ID: US10480597B2 - Status: Granted - Kind: B2 - Application number: 16/001,348 - Filed: 2018-06-06 - Published: 2018-12-13 - Granted: 2019-11-19 - Earliest claimed: 2018-06-06 - Assignees: Jtekt Corporation - Applicants: Jtekt Corporation - Inventors: Tomohiro Nozu; Yuta Takeuchi; Tsutomu Matsumoto; Shotaro Niimi - Web page: https://patentgrep.com/patent/US10480597B2 ## CPC - F16D 48/066: {Control of fluid pressure, e.g. using an accumulator (F16D48/062, F16D48/068 take precedence)} - B60K 17/02: characterised by arrangement, location, or kind of clutch - B60K 17/34: for driving both front and rear wheels, e.g. four wheel drive vehicles - B60K 17/344: having a transfer gear - B60K 17/3515: {with a clutch adjacent to traction wheel, e.g. automatic wheel hub} - B60K 23/0808: {for varying torque distribution between driven axles, e.g. by transfer clutch} - F16D 13/52: Clutches with multiple lamellae {; Clutches in which three or more axially moveable members are fixed alternately to the shafts to be coupled and are pressed from one side towards an axially-located member (F16D13/385 takes precedence)} - F16D 25/0638: with more than two discs, e.g. multiple lamellae - F16D 25/083: {Actuators therefor (F16D25/085 - F16D25/087 take precedence)} - F16D 25/14: {Fluid pressure control} - F16D 28/00: Electrically-actuated clutches (arrangements for synchronisation F16D23/02; clutches actuated directly by means of an electromagnet F16D27/00; automatic clutches F16D43/00 - F16D45/00; external control F16D48/00) - F16H 25/12: with reciprocation along the axis of rotation, e.g. gearings with helical grooves and automatic reversal - B60K 2023/0816: {for varying front-rear torque distribution with a central differential} - B60Y 2400/424: Friction clutches - F16D 29/005: {with a fluid pressure piston driven by an electric motor} - F16D 2048/0227: {Source of pressure producing the clutch engagement or disengagement action within a circuit; Means for initiating command action in power assisted devices} - F16D 2048/0245: {Electrically driven rotary pumps} - F16D 2048/0251: {Electric motor driving a piston, e.g. for actuating the primary cylinder} - F16D 2048/0266: {Actively controlled valves between pressure source and actuation cylinder} - F16D 2121/24: using motors - F16D 2125/36: Helical cams, Ball-rotating ramps - F16D 2500/1024: combined with hydraulic actuation - F16D 2500/10425: Differential clutch - F16D 2500/1045: Friction clutch - F16D 2500/3022: Current - F16D 2500/70404: Force - F16D 2500/7061: Feed-back - F16D 2500/7109: Pulsed signal; Generating or processing pulsed signals; PWM, width modulation, frequency or amplitude modulation - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - F16H: GEARING - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY ## Abstract A clutch apparatus includes a clutch hub, a clutch drum, a multi-plate clutch having inner clutch plates and outer clutch plates, a piston for pressing the multi-plate clutch, an electric motor, a moving mechanism for moving the piston in an axial direction in accordance with the amount of rotation of the electric motor, and a control unit for controlling the electric motor. When increasing a rotational force that is transmitted between the clutch hub and the clutch drum by increasing electric current that is supplied to the electric motor, the control unit moves the piston in the axial direction by temporarily supplying the electric motor with the electric current having a first current value that is greater than a second current value corresponding to a target rotational force that needs to be transmitted between the clutch hub and the clutch drum. ## Claims ### Claim 1 A clutch apparatus comprising: a first rotating member and a second rotating member that share an axis of rotation and that are rotatable relative to each other about the axis; a multi-plate clutch having a first clutch plate that rotates together with the first rotating member, the multi-plate clutch further having a second clutch plate that is aligned with the first clutch plate in an axial direction and that rotates together with the second rotating member; a pressing member that presses the multi-plate clutch; an electric motor that is supplied with electric current and that generates torque in accordance with the electric current; a moving mechanism that moves the pressing member in the axial direction in accordance with an amount of rotation of the electric motor; and a control unit that controls the electric motor, wherein the clutch apparatus allows adjustment of a rotational force that is transmitted between the first rotating member and the second rotating member through the multi-plate clutch, and when increasing the rotational force transmitted between the first rotating member and the second rotating member by increasing the electric current supplied to the electric motor, the control unit moves the pressing member in the axial direction by temporarily supplying the electric motor with the electric current having a first current value that is greater than a second current value corresponding to a target rotational force that needs to be transmitted between the first rotating member and the second rotating member. ### Claim 2 (depends on 1) The clutch apparatus according to claim 1, wherein the control unit calculates a cumulative rotational amount of the electric motor by cumulating an amount of rotation of the electric motor from an initial state where the pressing member is positioned with a distance between the multi-plate clutch, when increasing the rotational force transmitted between the first rotating member and the second rotating member by increasing the electric current supplied to the electric motor, the control unit supplies the electric motor with the electric current having the first current value greater than the second current value corresponding to the target rotational force until the cumulative rotational amount reaches a predetermined rotational amount that is less than a rotational amount corresponding to the target rotational force, and after the cumulative rotational amount reaches the predetermined rotational amount, the control unit supplies the electric motor with the electric current having the second current value corresponding to the target rotational force. ### Claim 3 (depends on 2) The clutch apparatus according to claim 2, wherein the control unit sets the predetermined rotational amount to a larger value as the target rotational force increases. ### Claim 4 (depends on 1) The clutch apparatus according to claim 1, wherein the moving mechanism includes a pump that discharges a hydraulic fluid by being driven by the electric motor, and the moving mechanism moves the pressing member toward the multi-plate clutch by pressure in a cylinder chamber that is supplied with the hydraulic fluid. ### Claim 5 (depends on 4) The clutch apparatus according to claim 4, wherein the moving mechanism further includes a control valve located between the pump and the cylinder chamber, a degree of opening of the control valve changes in accordance with electric current supplied from the control unit, and the control unit sets the degree of opening of the control valve to a first degree that is greater than a second degree corresponding to the target rotational force, while supplying the electric motor with the electric current having the first current value greater than the second current value corresponding to the target rotational force. ### Claim 6 (depends on 1) The clutch apparatus according to claim 1, wherein the moving mechanism includes a cam mechanism, the cam mechanism includes a first cam member and a second cam member, and generates an axial thrust force by relative rotation between the first cam member and the second cam member, and the rotation of the electric motor causes the relative rotation between the first cam member and the second cam member. ### Claim 7 A method for controlling a clutch apparatus, the clutch apparatus including: a first rotating member and a second rotating member that share an axis of rotation and that are rotatable relative to each other about the axis; a multi-plate clutch having a first clutch plate that rotates together with the first rotating member, the multi-plate clutch further having a second clutch plate that is aligned with the first clutch plate in an axial direction and that rotates together with the second rotating member; a pressing member that presses the multi-plate clutch; an electric motor that is supplied with electric current and that generates torque in accordance with the electric current; and a moving mechanism that moves the pressing member in the axial direction in accordance with an amount of rotation of the electric motor, the clutch apparatus configured to allow adjustment of a rotational force that is transmitted between the first rotating member and the second rotating member through the multi-plate clutch, the method comprising: when increasing the rotational force transmitted between the first rotating member and the second rotating member by increasing the electric current supplied to the electric motor, moving the pressing member in the axial direction by temporarily supplying the electric motor with the electric current having a first current value that is greater than a second current value corresponding to a target rotational force that needs to be transmitted between the first rotating member and the second rotating member.