Engine variable camshaft timing phaser with planetary gear set

Patent metadata

Field	Value
Publication number	US-10408096-B2
Application number	US-201715804816-A
Country	US
Kind code	B2
Filing date	Nov 6, 2017
Priority date	Mar 16, 2017
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

An engine variable camshaft timing phaser ( 10 ) includes a sprocket ( 12 ), three ring gears ( 26, 28, 30 ), multiple planet gears ( 24 ), and a sun gear ( 22 ). The sprocket ( 12 ) receives rotational drive input from an engine crankshaft. One or more of the three ring gear(s) ( 26, 28, 30 ) receives rotational drive input from the sprocket ( 12 ) and rotates with the sprocket ( 12 ), and the remaining ring gear(s) ( 26, 28, 30 ) transmit rotational drive output to an engine camshaft ( 62 ). All three of the ring gears ( 26, 28, 30 ) engage with the planet gears ( 24 ). And the sun gear ( 22 ) also engages with the planet gears ( 24 ). In operation, relative rotational speeds between the sprocket ( 12 ) and the sun gear ( 22 ) causes the engine camshaft ( 62 ) to advance or retard engine valve opening and closing.

First claim

What is claimed is:

1. An engine variable camshaft timing phaser ( 10 ), comprising:
a first ring gear ( 26 ) receiving rotational drive input;
a plurality of planet gears ( 24 ) engaged with said first ring gear ( 26 );
a sun gear ( 22 ) engaged with said plurality of planet gears ( 24 ), said sun gear ( 22 ) driven by an electric motor ( 32 );
a second ring gear ( 28 ) engaged with said plurality of planet gears ( 24 ); and
a third ring gear ( 30 ) engaged with said plurality of planet gears ( 24 );
wherein, in operation, relative rotational movement between said first ring gear ( 26 ) and said sun gear ( 22 ) caused by the electric motor ( 32 ) advances or retards engine valve opening and closing.

2. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 1 , wherein said second ring gear ( 28 ) transmits rotational drive output to an engine camshaft ( 62 ) and said third ring gear ( 30 ) is connected to the engine camshaft ( 62 ).

3. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 1 , wherein said second ring gear ( 28 ) transmits rotational drive output to an engine camshaft ( 62 ) and said third ring gear ( 30 ) receives rotational drive input from said first ring gear ( 26 ).

4. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 1 , wherein said first ring gear ( 26 ) and said plurality of planet gears ( 24 ) engage at a first axial section (S 1 ) of said plurality of planet gears ( 24 ), said second ring gear ( 28 ) and said plurality of planet gears ( 24 ) engage at a second axial section (S 2 ) of said plurality of planet gears ( 24 ), and said third ring gear ( 30 ) and said plurality of planet gears ( 24 ) engage at a third axial section (S 3 ) of said plurality of planet gears ( 24 ), said first axial section (S 1 ) situated between said second and third axial sections (S 2 , S 3 ).

5. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 4 , wherein loads transmitted to said plurality of planet gears ( 24 ) from said first ring gear ( 26 ), said second ring gear ( 28 ), and said third ring gear ( 30 ) are substantially balanced across said first axial section (S 1 ), said second axial section (S 2 ), and said third axial section (S 3 ).

6. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 5 , wherein said first axial section (S 1 ), said second axial section (S 2 ), and said third axial section (S 3 ) have individual axial widths that are approximately equal to each other.

7. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 6 , wherein the sum of the individual axial widths of said first axial section (S 1 ), said second axial section (S 2 ), and said third axial section (S 3 ) is approximately equal to the axial width (W) of sets of teeth ( 38 ) of said plurality of planet gears ( 24 ).

8. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 1 , further comprising a plate ( 16 ) receiving rotational drive input from said second ring gear ( 28 ) and transmitting rotational drive output to an engine camshaft ( 62 ).

9. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 1 , further comprising a carrier assembly ( 40 ) that supports rotation of said plurality of planet gears ( 24 ), said carrier assembly ( 40 ) including a pair of plates ( 42 , 44 ).

10. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 1 , wherein the engine variable camshaft timing phaser ( 10 ) lacks a carrier assembly for said plurality of planet gears ( 24 ), and substantially balanced loads across said plurality of planet gears ( 24 ) transmitted from said first ring gear ( 26 ), from said second ring gear ( 28 ), and from said third ring gear ( 30 ) help support the placement of said plurality of planet gears ( 24 ) in the engine variable camshaft timing phaser ( 10 ).

11. An engine variable camshaft timing phaser ( 10 ), comprising:
three ring gears ( 26 , 28 , 30 ), at least one of said three ring gears ( 26 , 28 , 30 ) receiving rotational drive input;
a plurality of planet gears ( 24 ) engaged with said three ring gears ( 26 , 28 , 30 ); and
a sun gear ( 22 ) engaged with said plurality of planet gears ( 24 );
wherein loads transmitted to said plurality of planet gears ( 24 ) from said three ring gears ( 26 , 28 , 30 ) are substantially balanced across an axial extent of said plurality of planet gears ( 24 ), and the substantially balanced loads preclude misalignment of said plurality of planet gears ( 24 ) with respect to said three ring gears ( 26 , 28 , 30 ).

12. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 11 , wherein at least one of said three ring gears ( 26 , 28 , 30 ) transmits rotational drive output to an engine camshaft ( 62 ).

13. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 11 , wherein two of said three ring gears ( 26 , 28 , 30 ) have a first number of individual teeth, and the remaining one of said three ring gears ( 26 , 28 , 30 ) has a second number of individual teeth, said first number of individual teeth differing from said second number of individual teeth by the number of said plurality of planet gears ( 24 ) or by a multiple thereof.

14. The engine variable camshaft timing phaser ( 10 ) as set forth in claim 11 , wherein the engine variable camshaft timing phaser ( 10 ) lacks a carrier assembly for said plurality of planet gears ( 24 ), and the substantially balanced loads across the axial extent of said plurality of planet gears ( 24 ) help support the placement of said plurality of planet gears ( 24 ) in the engine variable camshaft timing phaser ( 10 ).

15. An engine variable camshaft timing phaser ( 10 ), comprising:
a first ring gear ( 26 ) receiving rotational drive;
a plurality of planet gears ( 24 ) making teeth-to-teeth meshing with said first ring gear ( 26 );
a sun gear ( 22 ) making teeth-to-teeth meshing with said plurality of planet gears ( 24 ), said sun gear ( 22 ) driven by an electric motor ( 32 );
a second ring gear ( 28 ) making teeth-to-teeth meshing with said plurality of planet gears ( 24 );
a third ring gear ( 30 ) making teeth-to-teeth meshing with said plurality of planet gears ( 24 ); and
a plate ( 16 ) receiving rotational drive input from said second ring gear ( 28 ) and from said third ring gear ( 30 ), and said plate ( 16 ) transmitting rotational drive output to an engine camshaft ( 62 );
wherein said first ring gear ( 26 ) and said plurality of planet gears ( 24 ) mesh at a first axial section (S 1 ) of said plurality of planet gears ( 24 ), said second ring gear ( 28 ) and said plurality of planet gears ( 24 ) mesh at a second axial section (S 2 ) of said plurality of planet gears ( 24 ), and said third ring gear ( 30 ) and said plurality of planet gears ( 24 ) mesh at a third axial section (S 3 ) of said plurality of planet gears ( 24 ), said first axial section (S 1 ) situated between said second and third axial sections (S 2 , S 3 );

wherein, in order to angularly displace the engine camshaft ( 62 ) in a first direction relative to said first ring gear ( 26 ), the electric motor ( 32 ) drives said sun gear ( 22 ) at a greater rotational speed than said first ring gear ( 26 ), and in order to angularly displace the engine camshaft in a second direction relative to said first ring gear ( 26 ), the electric motor ( 32 ) drives said sun gear ( 22 ) at a lesser rotational speed than said first ring gear ( 26 ).

Assignees

• Borgwarner Inc

Inventors

• Pluta Christopher J
• Marsh Michael W

Classifications

• F01L2820/032

  Electric motors · CPC title

• F01L2250/02

  the camshaft being driven by chains · CPC title

• F16H57/082

  Planet carriers · CPC title

• F16H1/28

  with gears having orbital motion · CPC title

• F01L1/352 Primary

  using bevel or epicyclic gear · CPC title