# US 7,410,444 B2 · Drive unit for a hybrid motor vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,410,444 B2 - Document ID: US7410444B2 - Status: Granted - Kind: B2 - Application number: 11/362,580 - Filed: 2006-02-24 - Published: 2006-09-07 - Granted: 2008-08-12 - Earliest claimed: 2005-03-02 - Assignees: MTU Friedrichshafen GmbH - Inventors: Michael Groddeck; Joachim Huster - Web page: https://patentgrep.com/patent/US7410444B2 ## CPC - B60K 6/383: One-way clutches or freewheel devices - B60K 6/48: Parallel type - B60L 50/16: with provision for separate direct mechanical propulsion - F16D 27/102: with radially movable clutching members (F16D27/105 takes precedence) - F16D 43/18: with friction clutching members - F16D 2027/005: {Details relating to the internal construction of coils or to clutches having more than one coil in the same housing} - Y02T 10/62: Hybrid vehicles - Y02T 10/70: Energy storage systems for electromobility, e.g. batteries - Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors - 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 - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract In a drive unit for a hybrid motor vehicle including an internal combustion engine and a dynamoelectric machine to be connected to a transmission of the motor vehicle, wherein the drive unit comprises an input shaft connected to the internal combustion engine, an output shaft connected to the dynamoelectric machine for rotation therewith and a clutch for connecting the input shaft to the output shaft, the clutch includes centrifugal actuators for causing engagement of the clutch upon rotation at a speed in excess of a threshold value, springs counteracting the centrifugal actuators for causing the release of the clutch at a speed below the threshold value, and an electromagnetic actuators for causing engagement of the clutch at a speed below the threshold value to permit startup operation of the internal combustion engine by the dynamoelectric machine. ## Claims ### Claim 1 A drive unit (1) for a hybrid motor vehicle for coupling an internal combustion engine (2) and a dynamo electric machine (3) to a transmission (4), said drive unit (1) comprising an input shaft (5) which is connected to the internal combustion engine (2) for rotation therewith, a starter-generator (6) serving also as the dynamic electric machine (3), an output shaft (7) which is connected to the transmission (4) for rotation therewith, wherein the starter-generator (6) and the internal combustion engine (2) are capable of supplying power to said output shaft (7), a clutch (8) for coupling the starter generator (6) to the internal combustion engine (2), said clutch (8) including radially outwardly movable engagement members (11) for the centrifugal-force enhanced actuation of the clutch (8) and also stationary electromagnets (14) arranged radially around said engagement members (11) for generating an electromagnetic field, said engagement members (11) consisting of magnetic material providing for a magnetic force based engagement of the clutch (8) when the engagement members (11) are subjected to an electromagnetic field generated by energization of the stationary electromagnets (14). ### Claim 2 (depends on 1) A drive unit according to claim 1, wherein the clutch (8) comprises as mechanical components a first disc (9), which is connected for rotation with the input shaft (5), a second disc (10) arranged opposite the first disc (9), said engagement members (11) being friction wedges (11) arranged between the first and second discs (9, 10), springs (12) radially engaging the friction wedges (11) and support bolts (13) supporting the friction wedges (11) on the input shaft (5). ### Claim 3 (depends on 2) A drive unit according to claim 2, wherein the springs (12) are compression springs biasing the friction wedges (11) radially inwardly. ### Claim 4 (depends on 2) A drive unit according to claim 2, wherein the friction wedges (11), the springs (12) and the support bolts (13) are cooperating in such a way that, during rotation of the input shaft (5) below a threshold value (nGW), the friction wedges (11) are not in frictional engagement with the first and the second discs (9, 10). ### Claim 5 (depends on 2) A drive unit according to claim 2, wherein segments (15) of magnetic material are connected to the friction wedges (11) for pulling the friction wedges into engagement with the first and second discs (9, 10). ### Claim 6 (depends on 5) A drive unit according to claim 5, wherein the segments (15) are connected to the friction wedges for pulling the friction wedges (11) into engagement with the friction discs (9, 10). ### Claim 7 (depends on 6) A drive unit according to claim 6, wherein the stationary magnets (14) are pulling magnets (14) which cooperate with the segments (15) in such a way that, upon energization of electromagnets (14), the friction wedges (11) are pulled against the force of the springs (12) into engagement with the first and the second friction discs (9, 10). ### Claim 8 (depends on 1) A drive unit according to claim 1, wherein the starter-generator (6) includes a rotor (16) which is connected for rotation with the output shaft (7) and, by way of a metal-elastic coupling (18), with the clutch (8). ### Claim 9 A method of controlling a drive unit (1) for a hybrid motor vehicle for coupling an internal combustion engine (2) and a dynamoelectric machine (3) to a transmission (4), the drive unit (1) including an input shaft (5) which is connected for rotation with the internal combustion engine (2), an output shaft (7), which is connected to the transmission (4) and to the dynamoelectric machine (3) for driving the output shaft (7) or to be driven thereby and a clutch (8) for connecting the input shaft (5) to the output shaft (7) including means for a centrifugal force-enhanced engagement of the clutch (8) and electrically actuated pulling magnets (14) for initiating engagement of the clutch (8), said method comprising the steps of: for starting the internal combustion engine (2), energizing, the dynamoelectric machine (3) and also the pulling magnets (14) so as to close the clutch (8) and provide for rotation of the engine by the dynamoelectric machine (3), deactivating the pulling magnets (14) when the engine (2) speed has reached a threshold value (nGW) and the engine has started to operate, during the transition from operation by the internal combustion engine to an operation by the dynamo electric machine, lowering in a first step the speed of the internal combustion engine (2) to the threshold value (nGW) whereby the clutch (8) opens and, in a second step, activating the dynamoelectric machine (3) for driving the output shaft while the engine is shut down, for restarting the engine (2) while the dynamoelectric machine is activated, reducing, in a first step, the speed of the dynamoelectric machine (3) to the threshold value (nGW), energizing, in a second step, the pulling magnets (14) for closing the clutch (8) and, when the internal combustion engine has reached the speed of the threshold value (nGW), in a third step, deactivating the pulling magnetic (14).