llllllllllllllIll|||||Illlllllllllllllllll|||||||||||||||||||||||||||||||||
`U5005120282A
`
`United States Patent
`
`[19]
`
`[11] Patent Number:
`
`5,120,282
`
`Fja'llstriim
`
`[45] Date of Patent:
`
`Jun. 9, 1992
`
`[54] VEHICLE TRANSMISSION SYSTEM
`
`2500760 7/1976 Fed. Rep. of Germany .......... 475/1
`
`[76]
`
`Inventor:
`
`Bengt Fjiillstriim, Sb’dra Kungsv’agen
`9, 8-522 00 Tidaholm, Sweden
`
`Primary Examiner—Allan D. Herrmann
`Assistant Examiner—Ryan W. Massey
`
`[21] Appl. No.: 597,669
`
`[22] Filed:
`
`Oct. 16, 1990
`
`Int. Cl.5 ......................... F16H 37/06; B60K 1/02
`[51]
`[52] us. c1. ........................................ 475/5; 475/151;
`180/654
`[58] Field of Search ....................... 475/1, 2, 5, 6, 151;
`180/65.4
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`2,138,231 11/1938 Gebhardt ....................... 180/654 X
`2,196,368 4/1940 Thomson ................ 475/1 X
`.......
`2,205,999 6/1940 Bartlett et al.
`180/654 X
`
`l/1969 Christenson et a1.
`3,421,596
`ISO/65.4 X
`
`3,620,323 11/1971 Maeda ...................... 475/5 X
`
`3,699,351 10/1972 Addie ...............
`475/151 X
`
`3,921,745 11/1975 McCulloch et al.
`.. 180/654 X
`
`3,923,115 12/1975 Helling ....................... 475/5 X
`
`1/1984 Beck ............................... 475/5 X
`4,423,794
`5/1986 Albright, Jr. et a1.
`........
`4,588,040
`ISO/65.4 X
`4,953,646 9/1990 Kim .................................... 180/654
`
`FOREIGN PATENT DOCUMENTS
`
`ABSTRACT
`[57]
`This invention is concerned with vehicle transmission
`systems of the kind which include at least one transmis-
`sion drives shaft, at least one motor generator and at
`least one planetary gear means comprising a plant gear,
`sun gear and an outer ring. The motor generator en-
`gages the sun gear through the intermediary of a gear
`transmission assembly and the relative speed between
`the outer ring and the drive shaft is controlled by sup-
`plying energy to and taking energy from the motor
`generator. The sun gear is rotatably joumaled on the
`drive shaft, and the drive shaft is connected rigidly to
`the journalling points of the planet gears. The primary
`force is transmitted from the motor generator to the
`outer ring of the planetary gear means through the
`intermediary of a force transmission gear. As a result of
`this arrangement, when the sun gear is retarded by the
`motor generator, through the gear transmission assem-
`bly, the joumaling points of the plant gears will rotate
`around the gear center and drive the drive shaft, irre-
`spective of retardation of the sun gear.
`
`828187
`
`7/1949 Fed. Rep. of Germany .......... 475/1
`
`5 Claims. 1 Drawing Sheet
`
`
`
`Page 1 of 4
`Page 1 of 4
`
`FORD 1007
`FORD 1007
`
`

`

`US. Patent
`
`June 9, 1992
`
`5,120,282
`
`
`
`Page 2 of 4
`Page 2 of 4
`
`FORD 1007
`FORD 1007
`
`

`

`1
`
`5,120,282
`
`VEHICLE TRANSMISSION SYSTEM
`
`BACKGROUND OF THE INVENTION
`
`The present invention relates to a vehicle transmis-
`sion system for driving the drive shaft (or shafts) 'of a
`vehicle continuously at variable speed. The transmis-
`sion includes the combination of at least one electric
`motor generator and planetary or epicyclic gear means,
`comprising an outer ring, planet gears and a sun gear.
`
`10
`
`Summary of the Invention
`
`2
`when the vehicle is driven in a densely populated or
`built-up area.
`Other advantages afforded by the inventive transmis-
`sion system are found in the possibility of excluding the
`generator, start motor, clutch mechanism and gear box
`of conventional vehicles. The vehicle can also be driven
`and manipulated more readily when there is no need to
`change gear. This is particularly true when traction is
`limited and when there is a need for restricted vehicle
`speed, or when the vehicle engine concerned has a high
`drive torque.
`Because the vehicle can be driven at a constant, low
`speed, the exhaust gases will be cleaner than is other-
`wise the case. The inventive transmission system also
`enables energy to be recovered, by braking the vehicle
`initially through the motor generators. A four-wheel
`drive can also be readily installed on vehicles equipped
`with the inventive transmission system.
`Another important advantage afforded by the present
`invention is that the transmission system enables vehi-
`cles to be driven solely by electrical energy in towns
`and cities, even with limited battery capacity, without
`the need of large action radii.
`
`15
`
`20
`
`25
`
`30
`
`The object of the present invention is to provide a
`novel type of vehicle transmission system to which a
`conventional power plant, e.g. an internal combustion
`engine, and an electric motor can be connected in paral—
`lel, with the electric motor also capable of functioning
`as a generator, i.e. a motor generator, by which is meant
`a device capable of producing electric current and also
`of producing a driving force.
`The inventive system is mainly characterized in that
`the motor generator engages the sun gear through the
`intermediary of a gear transmission means, and in that
`the relative speed of the outer ring and the drive shaft,
`or shafts, is controlled by supplying energy to and tak-
`ing energy from the motor generator. The sun gear is
`rotatably joumaled on the drive shaft, which in turn has
`rigid connection with the joumaling points of the planet
`gear, and the primary force is transmitted from the
`motor generator to the outer ring through a force trans-
`mission gear.
`According to one preferred embodiment of the in-
`vention, the joumaling points of the planet gear or gears
`are located on an end plate which is mounted on the
`drive shaft.
`,
`According to another embodiment of the invention,
`the vehicle transmission system includes two planetary
`gear means which are in mirror image with one another
`and each of which includes a motor generator having
`gear transmission means.
`The energy generated by the motor generators is
`consumed, either totally or partially, by a further gener~
`ator motor when the vehicle is driven forwards, and the
`two planet gears have a mutually common outer ring.
`The invention is based on the concept of controlling
`vehicle speed in the differential of the terminal gear.
`The conventional terminal gear is then replaced prefer-
`ably with two planetary gear means arranged in mirror
`image with one another and each planetary gear means
`functions to control continuously the speed of a respec-
`tive vehicle drive wheel, or like traction device.
`Vehicle speed is controlled through the motor gener-
`ators and the driven planetary gears.
`One advantage afforded by the inventive transmis-
`sion system is that the speed of the drive motor, which
`may be a conventional internal combustion engine, can
`be held constant at varying traction. This enables the
`drive motor, or engine, to work at optimum efficiency
`with the subsequent minimization of harmful exhaust
`gases.
`Another advantage is that the vehicle can be driven
`in low gear solely by the motor generators themselves,
`by locking the outer ring of the planetary gear means.
`This feature in combination with the ability of charging
`the vehicle battery (or batteries) from an external bat-
`tery charging source will enable the vehicle to be
`driven in the absence of exhaust emissions, even with
`limited battery capacity, which is highly beneficial
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`So that the invention will be more readily understood
`and further features thereof made more apparent, exem-
`plifying embodiments of the invention will now be de-
`scribed in more detail with reference to the accompany-
`ing drawings, in which
`FIG. 1 is a schematic top view of a vehicle provided
`with an inventive transmission system; and FIG. 2 is a
`schematic view of a portion of the transmission system
`in of FIG. 1 taken generally along line 2—2.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`FIG. 1 illustrates a vehicle 1 provided with a power
`plant 2, for instance an internal combustion engine.
`Connected to the engine 2 is a power transmission gear
`3 which functiOns to transmit driving torque to a plane-
`tary gear means 4. The planetary gear means comprises
`an outer ring 5 which is operative to transmit said
`torque to planetary gears 6 and a sun gear 7, which are
`rotatably journaled on a shaft 8 which functions to
`drive vehicle wheels 9. The relative speed between the
`outer ring 5 and the drive shaft 8 is controlled by a
`motor generator 10 which coacts with a gear transmis-
`sion means 11 in a manner to enable the generator to
`continuously vary the speed of the sun gear 7. As will
`be seen from FIG. 1, the inventive system also includes
`a further motor generator 12, which functions to trans-
`mit driving torque to a second pair of driven vehicle
`wheels 13, via a drive shaft 14. This control of the speed
`of the drive shaft 8 results in the generation of electric
`current which can be used for charging a battery 15 and
`also for driving the further motor generator 12.
`In the illustration of FIG. 2, an imaginary triangle 18
`has been drawn with the corners of the triangle lying on
`the joumaling points 17 of the planet gears 6. This trian-
`gle is assumed to lie on an- end plate 16 (FIG. 1)
`mounted on the drive shaft 8, which is rigidly con-
`nected to the joumaling points of the planet gears. The
`illustrated arrangement is such that when, for instance,
`the sun gear 7 is retarded by the motor generator 10
`through the gear transmission means 11, the joumaling
`points 17 of the planet gears 6 will rotate independently
`
`35
`
`45
`
`50
`
`55
`
`65
`
`Page 3 of 4
`Page 3 of 4
`
`FORD 1007
`FORD 1007
`
`

`

`5,120,282
`
`4
`dance with the invention to drive the motor generators
`10, 10 with energy taken from the vehicle battery and
`therewith achieve reversed relative speed of the sun
`gear 7 (positive rotation), which therewith causes the
`drive shaft 8 to be rotated at a higher speed.
`The speed of the power plant 2 can be varied from
`between 1800 and 3600 rpm, within a vehicle speed
`range of 53—106 km/hour, without the sun gear 7 rotat-
`ing, which enables the vehicle to be propelled in the
`manner of a conventional vehicle within these limits, or
`alternatively at a constant power-plant speed (selective)
`and the speed controlled by supplying energy from the
`battery 12 (positive rotation of the sun gear 7).
`A suitable battery rating is about 200 Ampere hour
`which gives an action radius of about 30 km at a vehicle
`speed of 50 km/hour, while recovering energy when
`braking the vehicle power unit through the motor gen—
`erators 10, 10 and 12.
`I claim:
`
`1. A vehicle transmission system having a drive shaft
`or drive shafts which can be driven continuously at
`varying speeds, said system comprising a combination
`of at least one motor generator and at least one plane-
`tary gear means having an outer ring, a planet gear and
`a sun gear, wherein the motor generator engages the
`sun wheel through the intermediary of a gear transmis-
`sion means; wherein the relative speed between said
`outer ring and said drive shaft or shafts is controlled by
`supplying energy to and taking energy from said motor
`generator; wherein the sun gear is rotatably joumaled
`to the drive shaft or shafts; wherein said drive shaft or
`shafts is, or are, rigidly connected to the journal points
`of the planet gears; and wherein a force transmission
`gear is provided for transmitting the primary force from
`the motor generator to the outer ring.
`2. The transmission system of claim 1, wherein the
`journaling points of the planet gears lie on an end plate
`mounted on the drive shaft or respective drive shafts,
`and wherein said shaft or shafts is or are rigidly con—
`nected to the jounaling points of the planet gears.
`3. The transmission system of claim 1 wherein the
`system comprises two planetary gear means which are
`arranged in mirror image with one another and each of
`which includes a respective drive shaft and a respective
`motor generator with gear transmission means.
`4. The transmission system of claim 3, wherein the
`two planetary gear means have a common outer ring.
`5. The transmission system according to claim 1,
`wherein said system includes a further motor generator
`which when the vehicle is driven forwards takes energy
`generated by the motor generators.
`*
`t
`t
`t
`*
`
`3
`thereof around the gear centre and therewith rotate the
`drive shaft 8. When the outer ring 5, and therewith also
`the planet gears 6, is driven by the power plant or inter—
`nal combustion engine 2, via the power transmission
`gear 3, the drive shaft 8 and the sun gear 7 are caused to
`rotate by the planet gears 6, this rotation being transmit—
`ted through the gear transmission means 11 and driving
`the motor generator 10 as an electric generator for
`charging the battery 15. Since the sun gear 7 is rotatably
`joumaled on the drive shaft 8,
`the rotational speed
`thereof is independent of the rotational speed of the
`drive shaft but dependent on the resistance exerted by
`the motor generator 10.
`The novelty of the present invention thus resides in
`the fact that the forward speed of the vehicle can be
`controlled with the aid of the motor generators 10, by
`controlling the relative speed of the gears in the plane-
`tary gear means 4, therewith enabling the speed of the
`drive shaft or shafts 8 to be varied continuously. Surplus
`energy generated by the motor generator or generators
`10 can be used to drive the further motor generator 12
`which drives the vehicle wheels 13 on the wheel axles
`
`14. The power transmission gear 3 may comprise sev-
`eral torque transmission gears capable of being engaged
`and disengaged selectively to achieve mutually differ-
`ent transmission ratios. Although not shown, the inven-
`tive system includes means for locking the outer ring 5
`of the planetary gear means when the vehicle 1 is pro-
`pelled solely by the motor generators 10 and/or the
`further motor generator 12. The invention also enables
`energy to be recovered through the motor generators
`10 and 12 when braking the engine of the vehicle.
`The drive transmission can be suitably constructed so
`that when starting the vehicle and driving said vehicle
`at low speeds, i.e. speeds beneath about 53 km/hour,
`and also when reversing the vehicle, the vehicle will be
`driven solely by the motor generators 10, 10, 12. When
`the vehicle is driven at a speed of about 53 km/hour to
`106 lam/hour, the power plant, or engine 2 is engaged,
`wherein speed control is effected when rotation of the
`sun gear 7 is retarded (negative rotation) by the motor
`generators 10, 10. The battery 15 is therewith recharged
`and surplus energy is consumed by the further motor
`generator 12. Thus, the batteries will be recharged opti—
`mally on each occasion, which is highly beneficial in
`view of the fact that heavy, momentary booster charg-
`ing of the battery results in the generation of undesir-
`able heat.
`For the purpose of enabling the vehicle to be driven
`at higher speeds than 106 km/hour, for instance when
`overtaking, (e.g. an overtaking speed of 159 km/hour)
`while retaining vehicle traction, it is possible in accor-
`
`10
`
`15
`
`20
`
`25
`
`3O
`
`35
`
`45
`
`50
`
`55
`
`65
`
`Page 4 of 4
`Page 4 of 4
`
`FORD 1007
`FORD 1007
`
`