Planetary transmission for a motor of a drive system of a wheel of a motor vehicle

• US 5,685,798 A
• Filed: 06/16/1995
• Issued: 11/11/1997
• Est. Priority Date: 06/18/1994
• Status: Expired due to Fees

• Current Assignee: Fichtel & Sachs AG
• Original Assignee: Fichtel & Sachs AG
• Inventors: Hey, Asmund, Lutz, Dieter
• Primary Examiner(s): TA, KHOI QUANG
• Application Number:
  US08/491,094
• Time in Patent Office: 879 Days
• Field of Search: 475/149, 475/317, 475/323, 475/331, 475/346, 180/65.5, 180/65.6
• US Class Current: 475/331
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 17/046 with planetary gearing having orbital motion
• CPC Class Codes: B60K 17/145 the electric gearing being disposed in or adjacent to traction wheel
• CPC Class Codes: F16H 1/28 with gears having orbital motion
• CPC Class Codes: H02K 7/116 with gears

Abstract

For the individual drive of a wheel of a motor vehicle, a planetary transmission can be combined into a single module with a motor. The planetary transmission has a sun wheel which on a motor shaft of the motor, a ring gear and a planet carrier with planet wheels which are rotationally mounted on journals. The planet carrier and the ring gear are non-rotationally connected to a support part which simultaneously forms the transmission housing, or to a driven shaft part which is rotationally mounted on the support part. The planet carrier is designed as a shaped sheet metal and comprises a sheet metal base wall which runs axially perpendicular to the axis of rotation of the planetary transmission, into which sheet metal base wall the journals are shaped in a cup shape. Projecting in the same direction as the journals from the outside circumference of the sheet metal base wall is a circumferential wall in which there is a toothed portion for the non-rotational coupling of the planet carrier with the support part or the driven shaft part. The planet wheels are held by a ring-shaped positioning disc on the shaped sheet metal part. Projecting axially from the outside circumference of the positioning disc are webs which are engaged between neighboring planet wheels, and which are welded to the sheet metal base wall. The planet carrier can be manufactured easily, and the forces which are exerted on it during operation are essentially equalized or compensated.

Claims

1. A planetary transmission for a drive train of a motor vehicle, the drive train having motor means for generating mechanical power, the motor means having an output shaft for outputting mechanical power and means for rotating said output shaft for outputting mechanical power, a housing disposed about at least a portion of said motor means, at least one wheel for receiving mechanical power from the motor to drive the motor vehicle, and a drive shaft connected to the at least one wheel for transferring mechanical power to the at least one wheel, the planetary transmission for connecting said output shaft of said motor means to the drive shaft of the drive train for rotating the drive shaft with said output shaft, said planetary transmission comprising:

a sun gear;

means for non-rotatably connecting said sun gear to the output shaft for rotation of said sun gear with the output shaft;

a ring gear being disposed substantially concentrically about said sun gear;

means for non-rotatably connecting said ring gear to one of;

the housing and the drive shaft;

a plurality of planet gears being disposed about said sun gear, between said sun gear and said ring gear, each of said plurality of planet gears being intermeshed with both said sun gear and said ring gear;

a planet gear carrier for rotatably mounting said plurality of planet gears between and intermeshed with said sun gear and said ring gear;

said planet gear carrier comprising means for holding said plurality of planet gears with said planet gear carrier for holding said plurality of planet gears and said planet gear carrier as an integral, unitary unit at least during assembly of said planetary transmission;

means for slidably engaging said integral unitary unit and the other of;

the housing and the drive shaft, for non-rotatably connecting said integral unitary unit with the other of;

the housing and the drive shaft;

said planet gear carrier comprising;

a first ring-shaped plate having a central opening therein for being disposed about the output shaft, said first ring-shaped plate defining a plane, and said first ring-shaped plate for being disposed about the output shaft with said plane transverse to the output shaft; and

a plurality of axles extending from said ring-shaped plate, for rotatably mounting ones of said plurality of planet gears thereon, said plurality of axles extending substantially perpendicular to said ring-shaped plate;

said ring-shaped plate comprising a radially outer edge, said radially outer edge comprising toothing disposed circumferentially thereabout;

the other of the housing and the drive shaft comprising toothing for interlocking with said toothing of said radially outer edge; and

said toothing of said radially outer edge comprising said means for slidably engaging said integral unitary unit and the other of the housing and the drive shaft.

2. The planetary transmission according to claim 1, wherein said plurality of axles and said toothing of said radially outer edge comprise integral components of said ring-shaped plate, integrally formed with said ring-shaped plate as a single unitary component.

3. The planetary transmission according to claim 2, wherein:

said radially outer edge of said ring-shaped plate comprises a cylindrical wall projecting from said ring-shaped plate in the same direction as said axles;

said cylindrical wall comprising said toothing of said ring-shaped plate;

said cylindrical wall having an axial length away from said ring-shaped plate;

said axles having an axial length away from said ring-shaped plate; and

said axial length of said cylindrical wall is greater than said axial length of said axles.

4. The planetary transmission according to claim 3, wherein:

said means for connecting said ring gear to one of;

the housing and the drive shaft comprises means for connecting said ring gear to the drive shaft;

said ring gear extends axially adjacent said cylindrical wall over at least a portion of the axial length of said cylindrical wall;

said cylindrical wall is disposed radially outwardly of said ring gear;

said axles have a first end disposed adjacent said ring-shaped plate, and a second end opposite said first end and disposed away from said ring-shaped plate;

said means for holding further comprises a disc-shaped member disposed adjacent said second end of said axles and parallel to said ring-shaped plate; and

said disc-shaped member comprising means for retaining said disc-shaped member on said single unitary component for axially retaining said planet gears on said axles.

5. The planetary transmission according to claim 4, wherein:

said disc-shaped member has an outer radial edge;

said disc-shaped member comprises a plurality of webs disposed at said outer radial edge thereof, substantially transverse to said disc-shaped member and in a direction towards said ring-shaped plate;

said webs being disposed between adjacent ones of said plurality of planet gears, and said webs having a first end disposed adjacent said disc-shaped member and a second end disposed adjacent said ring-shaped plate, said webs comprising said means for retaining said disc-shaped member on said single unitary component;

said radial outer edge of said disc-shaped member extends radially outwardly of said axles and substantially adjacent said ring gear;

said axles comprise cylindrical tubes pressed into said ring-shaped plate;

said second end of said axles comprising cover means closing off said cylindrical tubes;

said axles further comprise bearing sleeves disposed thereabout, said planet gears being disposed rotationally on said bearing sleeves;

said bearing sleeves comprise roller bearings;

said means for retaining said disc-shaped member on said single unitary component comprises a weld between said second end of said webs and said ring-shaped plate;

said plurality of planet gears comprise five planet gears disposed at about 72 degrees in relation to one another in a circumferential direction;

said sun gear has a central opening therein for being disposed on the output shaft of the motor means;

said means for non-rotationally connecting said sun gear to the output shaft comprises toothing disposed radially inwardly within said sun gear, the output shaft comprising toothing for meshing with said toothing of said sun gear;

said planet gears have an axial length on said axles, said axial length of said planet gears being less than said axial length of said axles;

said axles further comprise bearing rings disposed thereabout adjacent said first and second ends of said axles with said planet gears disposed between said bearing rings;

said ring gear comprises a substantially bowl-shaped member, said bowl shaped member having a base portion with a cylindrical wall extending from said base portion, the cylindrical wall of said bowl-shaped member having radially inwardly disposed teeth thereon for intermeshing with said planet gears;

said base portion having a first diameter, said cylindrical wall of said bowl-shaped member having a second diameter, said second diameter being greater than said first diameter;

said bowl-shaped member being disposed substantially coaxial to said single unitary component;

said planetary transmission further comprises a retaining ring disposed about said base portion of said bowl shaped member, and means for fastening said retaining ring to the housing to hold said planetary transmission with the housing; and

said planetary transmission further comprises bearing means disposed about said base portion of said bowl-shaped member between said bowl-shaped member and said retaining ring.

6. A method of assembling a planetary transmission in a drive train for a motor vehicle, the drive train having motor means for generating mechanical power, the motor means having an output shaft for outputting mechanical power and means for rotating the output shaft for outputting mechanical power, a housing disposed about at least a portion of the motor means, at least one wheel for receiving mechanical power from the motor means to drive the motor vehicle, a drive shaft connected to the at least one wheel for transferring mechanical power to the at least one wheel, and the planetary transmission for connecting the output shaft of the motor means to the drive shaft of the drive train for rotating the drive shaft with the output shaft, the planetary transmission comprising:

a sun gear;

means for non-rotatably connecting the sun gear to the output shaft for rotation of the sun gear with the output shaft;

a ring gear disposed substantially concentrically about the sun gear;

means for non-rotatably connecting the ring gear to one of;

the housing and the drive shaft;

a plurality of planet gears disposed about the sun gear, between the sun gear and the ring gear, each of the plurality of planet gears being intermeshed with both the sun gear and the ring gear;

a planet gear carrier for rotatably mounting the plurality of planet gears between and intermeshed with the sun gear and the ring gear;

the planet gear carrier comprising means for holding the plurality of planet gears with the planet gear carrier for holding the plurality of planet gears and the planet gear carrier as an integral, unitary unit at least during assembly of the drive train;

said method comprising the steps of;

non-rotatably connecting the sun gear to the output shaft for rotation of the sun gear with the output shaft;

disposing the ring gear substantially concentrically about the sun gear;

non-rotatably connecting the ring gear to the one of;

the housing and the drive shaft;

rotatably mounting the plurality of planet gears on the planet gear carrier;

holding the plurality of planet gears on the planet gear carrier to provide the integral, unitary unit;

disposing the integral, unitary unit between the output shaft and the drive shaft;

intermeshing the plurality of planet gears with both the sun gear and the ring gear;

slidably engaging said integral unitary unit and the other of;

the housing and the drive shaft, for non-rotatably connecting said integral unitary unit with the other of;

the housing and the drive shaft;

forming said planet gear carrier as a first ring-shaped plate having a central opening therein for being disposed about the output shaft, said first ring-shaped plate defining a plane, and said first ring-shaped plate for being disposed about the output shaft with said plane transverse to the output shaft;

providing a plurality of axles extending from said ring-shaped plate, for rotatably mounting ones of said plurality of planet gears thereon, said plurality of axles extending substantially perpendicular to said ring-shaped plate;

providing toothing disposed circumferentially about a radially outer edge of said ring-shaped plate;

providing corresponding toothing on the other of the housing and the drive shaft for interlocking with said toothing of said radially outer edge; and

slidably engaging said integral unitary unit and the other of the housing and the drive shaft by slidably intermeshing said teeth of said radially outer edge with the corresponding toothing of the other of the housing and the drive shaft.

7. The method according to claim 6, further comprising forming said plurality of axles and said toothing of said radially outer edge as integral components of said ring-shaped plate to form a single unitary component comprising said axles and said toothing.

8. The method according to claim 7, further comprising:

forming said radially outer edge of said ring-shaped plate as a cylindrical wall projecting from said ring-shaped plate in the same direction as said axles, said forming comprising bending an outer peripheral portion of said ring-shaped plate in an axial direction to form said cylindrical wall, said cylindrical wall having an axial length away from said ring-shaped plate;

forming said toothing of said ring-shaped plate on said cylindrical wall;

forming said ring-shaped plate of sheet metal;

forming said plurality of axles by pressing said plurality of axles out of said ring-shaped plate to deform the sheet metal into cylindrical axles, said axles having an axial length away from said ring-shaped plate; and

forming said cylindrical wall and said plurality of axles such that said axial length of said cylindrical wall is greater than said axial length of said axles.

9. The method according to claim 8, wherein:

said connecting of said ring gear to one of;

the housing and the drive shaft comprises connecting said ring gear to the drive shaft;

providing said ring gear axially adjacent said cylindrical wall over at least a portion of the axial length of said cylindrical wall;

disposing said cylindrical wall radially outwardly of said ring gear;

disposing a first end of said axles adjacent said ring-shaped plate, and a second end opposite said first end and disposed away from said ring-shaped plate;

providing a disc-shaped member adjacent said second end of said axles and parallel to said ring-shaped plate to provide said means for holding;

configuring said disc-shaped member to comprise means for

retaining said disc-shaped member on said single unitary component for axially retaining said planet gears on said axles; and

retaining said disc-shaped member on said single unitary unit with said means for retaining.

10. The method according to claim 9, wherein said disc-shaped member has an outer radial edge, and said method further comprises the steps of:

providing said disc-shaped member with a plurality of webs disposed at said outer radial edge thereof, and disposing said webs substantially transverse to said disc-shaped member and in a direction towards said ring-shaped plate;

disposing said webs between adjacent ones of said plurality of planet gears, said webs having a first end disposed adjacent said disc-shaped member and a second disposed adjacent said adjacent said ring-shaped plate;

welding said second edge of said webs to said ring-shaped plate to retain said disc-shaped member on said single unitary unit;

configuring said radial outer edge of said disc-shaped member to extend radially outwardly of said axles and substantially adjacent said ring gear;

disposing bearing sleeves about said axles, and disposing said planet gears rotationally on said bearing sleeves; and

providing roller bearings as said bearing sleeves.

11. A planetary transmission for a drive train of a motor vehicle, the drive train having a motor for generating mechanical power, the motor having an output shaft for outputting mechanical power, a housing disposed about at least a portion of the motor, at least one wheel to receive mechanical power from the motor to drive the motor vehicle, and a drive shaft connected to the at least one wheel to transfer mechanical power to the at least one wheel, the planetary transmission to connect said output shaft of the motor to the drive shaft of the drive train for rotating the drive shaft with the output shaft, said planetary transmission comprising:

a sun gear for being non-rotatably connected to the output shaft;

a driven shaft part;

said driven shaft part for being operatively connected to the drive shaft;

a ring gear being non-rotatably connected to one of the housing and the driven shaft part;

said ring gear being disposed substantially concentrically about said sun gear;

a plurality of planet gears being disposed about said sun gear;

said plurality of planet gears being disposed between said sun gear and said ring gear;

said plurality of planet gears each being intermeshed with both said sun gear and said ring gear;

a planet gear carrier;

said planet gear carrier comprising means for rotatably mounting said plurality of planet gears;

said rotatably mounting means comprising;

a ring-shaped plate having a central opening therein for being disposed about the output shaft;

said ring-shaped plate for being disposed transverse to the output shaft;

said ring-shaped plate comprising a radially outer edge;

a plurality of axles;

said plurality of axles extending from said ring-shaped plate in a substantially perpendicular direction to said ring-shaped plate; and

said plurality of planet gears each being disposed about one of said plurality of axles;

means for non-rotatably connecting said planet gear carrier with the other of the housing and said driven shaft part;

said planet gear carrier connecting means comprising means for slidably engaging said planet gear carrier and the other of the housing and said driven shaft part; and

said slidably engaging means comprising;

a first toothing being disposed circumferentially about said radially outer edge of said ring-shaped plate; and

a second toothing being disposed on the other of the housing and the driven shaft part to interlock with said first toothing.

12. The planetary transmission according to claim 11, wherein said plurality of axles, said first toothing and said ring shaped plate together form a single unitary component.

13. The planetary transmission according to claim 12, wherein:

said radially outer edge of said ring-shaped plate comprises a cylindrical wall;

said cylindrical wall is disposed substantially perpendicular to said ring-shaped plate;

said cylindrical wall is disposed adjacent to said plurality of axles;

said cylindrical wall comprises said first toothing;

said cylindrical wall having a substantial axial length;

said plurality of axles each having a substantial axial length; and

said axial length of said cylindrical wall is greater than said axial length of each of said plurality of axles.

14. The planetary transmission according to claim 13, wherein:

said ring gear is non-rotatably connected to said driven shaft part;

said ring gear extends axially adjacent to said cylindrical wall over at least a portion of the axial length of said cylindrical wall;

said cylindrical wall is disposed radially outward of said ring gear;

said plurality of axles each comprise a first end disposed adjacent to said ring-shaped plate;

said plurality of axles each comprise a second end disposed opposite said first end;

said rotatably mounting means further comprises a disc-shaped member;

said disc-shaped member is disposed adjacent to said second ends of said plurality of axles;

said disc-shaped member is disposed substantially parallel to said ring-shaped plate; and

said disc-shaped member comprises means for retaining said disc-shaped member on said ring-shaped plate to axially retain said plurality of planet gears on said plurality of axles.

15. The planetary transmission according to claim 14, wherein:

said disc-shaped member comprises an outer radial edge;

said outer radial edge of said disc-shaped member is disposed radially outward from said plurality of axles;

said outer radial edge of said disc-shaped member is disposed substantially adjacent to said ring gear;

said retaining means comprises a plurality of webs;

said plurality of webs is disposed adjacent to said outer radial edge;

said plurality of webs is disposed substantially transverse to said disc-shaped member;

said plurality of webs extends from said disc-shaped member towards said ring-shaped plate;

said plurality of webs each comprise a first end disposed adjacent to said disc-shaped member and a second end disposed adjacent to said ring-shaped plate;

each web of said plurality of webs is disposed between adjacent planet gears of said plurality of planet gears;

said retaining means comprises a weld between said second end of said webs and said ring-shaped plate;

said plurality of axles comprises cylindrical tubes pressed into said ring-shaped plate;

said second end of said axles comprises cover means for covering said cylindrical tubes at said second end;

said rotatably mounting means further comprises bearing sleeves disposed about said plurality of axles;

said bearing sleeves comprise roller bearings;

said plurality of planet gears are rotationally disposed on said bearing sleeves;

said plurality of planet gears comprise five planet gears;

said five planet gears are equally spaced about said sun gear;

said sun gear has a central opening for being disposed on the output shaft;

said sun gear comprises a third toothing disposed on said sun gear and facing the output shaft to mesh with toothing of the output shaft;

said plurality of planet gears each have an axial length;

said axial length of said plurality of planet gears is less than said axial length of said plurality of axles;

said rotatably mounting means further comprises adapter rings disposed about said plurality of axles;

said adapter rings are disposed adjacent to said first and second ends of said plurality of axles;

said plurality of planet gears are disposed between said adapter rings;

said driven shaft part comprises a base portion and a shoulder portion extending from said base portion;

said base portion of said driven shaft part has a first diameter;

said shoulder portion of said driven shaft part has a second diameter;

said second diameter being greater than said first diameter;

said ring gear is disposed immediately adjacent to said shoulder portion of said driven shaft part; and

said ring gear comprises radially inwardly disposed teeth to intermesh with said planet gears.

16. The planetary transmission according to claim 15 further comprises:

a retaining ring disposed adjacent to said base portion of said driven shaft part;

means for fastening said retaining ring to the housing to hold said planetary transmission within the housing;

a bearing disposed about said base portion of said driven shaft part;

said bearing is disposed between said driven shaft part and said retaining ring;

a kinetic seal; and

said kinetic seal is disposed between said driven shaft part and said retaining ring.

17. The planetary transmission according to claim 13, wherein:

said ring gear is connected to said housing; and

said planet gear carrier connecting means being means for connecting said planet gear carrier and said driven shaft part.