Smart Phasing – Needs based concepts for camshaft phasing

Smart Phasing –

Needs based concepts for camshaft phasing systems

Kevin Poole

Schaeffler Symposium 2014 Kevin Poole 1

Functional requirements for VCT Systems

En

gin

e lo

ad

Flexibility for engine start

Time

Ca

ms

ha

ft a

ng

le

Engine

speed

Camshaft timing accuracy

Time

Da

Shifting velocity

Time

Da

Dt

Engine speed


…and the changing oil pressure landscape

En

gin

e lo

ad

Flexibility for engine start

Time

Ca

ms

ha

ft a

ng

le

Engine

speed

Camshaft timing accuracy

Time

Da

Shifting velocity

Time

Da

Dt

Engine speed

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 1000 2000 3000 4000 5000 6000 7000

Oil

pre

ss

ure

in

ba

r

Engine speed in rpm

2004

Engine type: I4



0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 1000 2000 3000 4000 5000 6000 7000

Oil

pre

ss

ure

in

ba

r

Engine speed in rpm

2004

2008

Engine type: I4



0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 1000 2000 3000 4000 5000 6000 7000

Oil

pre

ss

ure

in

ba

r

Engine speed in rpm

2004

2008

2012

Engine type: I4


Comparison of system capabilities S

hif

tin

g v

elo

cit

y

Oil

co

ns

um

pti

on

High Low High Low

HCP with cartridge OCV

HCP with central OCV

Pressure accumulator

ECP

OPPORTUNITY!

-10

-5

0

5

10

-100 -50 0 50 100

Dyn

am

ic C

am

sh

aft

to

rqu

e in

Nm

Camshaft angle in °Cam


Fundamentals of cam phasing dynamic cam torque

Stator Rotor

-10

-5

0

5

10

-100 -50 0 50 100

Dyn

am

ic C

am

sh

aft

to

rqu

e in

Nm

Camshaft angle in °Cam


Fundamentals of cam phasing dynamic cam torque

Stator Rotor


Fundamentals of cam phasing dynamic cam torque C

am

sh

aft

ph

aser

an

gle

in

°C

am

Retard

Advance


Fundamentals of cam phasing oil flow

FPull = const.

Bowl

pEnviroment

Vacuum

"B"

A

B

Stator Rotor

"B"


Solving the vacuum issue oil reservoir

Camshaft phaser

P T

A B

A B

Oil control valve

A

B

Oil volume


Solving the vacuum issue oil reservoir

Time

a (Standard)

Q (Standard)

Ave

rag

e o

il f

low

Q o

il p

um

p

Cam

sh

aft

an

gle

a

Q (Smart phaser)

DQ

a (Smart phaser)

Da


Design - camshaft phaser

Standard

Oil res

volume

Reed check valve

Smart Phaser

Stator

Rotor

Sprocket


Design - oil control valve

B A

T

P

Standard

B A

P

Oil reservoir supply port

V

Smart Phaser


Oil flow – phasing to base position

A - A

A

Central solenoid Camshaft phaser

Central valve

Camshaft

T

P

B A

B


Simulation – Standard phaser shift velocity vs oil flow

0

100

200

300

400

500

600

0 2 4 6 8 10

Sh

ifti

ng

ve

loc

ity i

n

°Cr/

s

Average oil flow of oil pump in L/min

0

100

200

300

400

500

600

0 2 4 6 8 10

Sh

ifti

ng

ve

loc

ity i

n

°Cr/

s


0

100

200

300

400

500

600

0 2 4 6 8 10

Sh

ifti

ng

ve

loc

ity i

n

°Cr/

s


1,5 bar

2,5 bar

3,5 bar

4,5 bar

0,5 bar ±5 Nm

±20 Nm

Camshaft torque

Oil pressure


Simulation – Smart phaser shift velocity vs oil flow

0

100

200

300

400

500

600

0 2 4 6 8 10

Ve

rste

llg

es

ch

win

dig

ke

it [

°KW

/s]

Mittlerer Ölvolumenstom in L/min

0

100

200

300

400

500

600

0 2 4 6 8 10

Sh

ifti

ng

ve

loc

ity i

n

°Cr/

s


±5 Nm

0,5 bar 1,5 bar 2,5 bar

3,5 bar

4,5 bar

±20 Nm


Simulation – Smart phaser shift velocity vs oil flow

0

50

100

150

200

250

300

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

Sh

ifti

ng

ve

loc

ity i

n

°Cr/

s


±5 Nm

±10 Nm

±15 Nm

±20 Nm Standard

Smart phaser


Test results – shift velocity

-300

-200

-100

0

100

200

300

0 1000 2000 3000 4000 5000 6000 7000 8000

Sh

ifti

ng

ve

loc

ity i

n

°Cr/

s

Engine speed in rpm

Oil temperature: 90°C

to a

dvance

to

reta

rd

1200 rpm Sh

ifti

ng

ve

loc

ity i

n °

Cr/

s

Engine speed in rpm

Standard

Smart phaser


Test results C

am

sh

aft

ph

aser

an

gle

in

°C

am

Retard

Advance

ZOOM


Test results

R

A

Ca

ms

ha

ft p

ha

se

r a

ng

le in

°C

am

Standard

Oil

pre

ss

ure

in

ba

r

Oil pressure in camshaft


Test results

Oil pressure in chamber A

R

A

Oil

pre

ss

ure

in

ba

r C

am

sh

aft

ph

as

er

an

gle

in

°C

am

Standard


Test results

Oil pressure in chamber B

Oil

pre

ss

ure

in

ba

r

R

A

Ca

ms

ha

ft p

ha

se

r a

ng

le in

°C

am

Standard


Test results

Standard

Oil

pre

ss

ure

in

ba

r

R

A

Ca

ms

ha

ft p

ha

se

r a

ng

le in

°C

am

Smart phaser


Test results

+0

.5 °

Ca

m

Vacuum

Oil

pre

ss

ure

in

ba

r

R

A

Ca

ms

ha

ft p

ha

se

r a

ng

le in

°C

am

Standard Smart phaser


Comparison of system capabilities - revisited S

hif

tin

g v

elo

cit

y

Oil

co

ns

um

pti

on

High Low High Low

HCP with cartridge OCV

HCP with central OCV

Pressure accumulator

ECP

Smart phaser


Smart phasing solving the hydraulic camphasing puzzle

significantly reduced

oil consumption

higher shifting velocity

at equal controllability / and significantly reduced

oil consumption

higher shifting velocity

at equal controllability

If something doesn’t yet exist,

I invent it. ” ‟

Enrico Luccherini

1932 -

If something doesn’t yet exist,

invents it! ” ‟

VCT Systems Team

Documents

Smart Phasing – Needs based concepts for camshaft phasing