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8/10/2019 Cam Dynamic Synthesis
1/23
Al-Khwarizmi
Engineering
Journal
Al-Khwarizmi Engineering Journal, Vol. 10, No. 1, P.P. 1- 23 (2014)
Cam Dynamic Synthesis
Florian Ion T. Petrescu* Relly Victoria V. Petrescu***Department of Theory of Mechanisms and Robots/ Polytechnic University of Bucharest / Romania / Europe
** Department of Transport, Traffic & Logistic Department / Polytechnic University of Bucharest/ Romania / Europe
*E-mail: [email protected]
**E-mail: [email protected]
(Received 10 October 2013; accepted 4 February 2014)
Abstract
The paper presents an original method to make the geometric synthesis of the rotary cam and translated tappet with
roll. Classical method uses to the geometric synthesis and the reduced tappet velocity, and in this mode the geometric
classic method become a geometric and kinematic synthesis method. The new geometric synthesis method uses just the
geometric parameters (without velocities), but one utilizes and a condition to realize at the tapped the velocities
predicted by the tapped movement laws imposed by the cam profile. Then, it makes the dynamic analyze for the
imposed cam profile, and one modify the cam profile geometric parameters to determine a good dynamic response
(functionality). In this mode it realizes the dynamic synthesis of the cam, and we obtain a normal functionality.
Keywords: Geometric synthesis, Dynamic synthesis, Rotary cam, Translated tappet with roll.
1. Introduction
In conditions which started to magnetic
motors, oil fuel is decreasing, energy which wasobtained by burning oil is replaced with nuclear
energy, hydropower, solar energy, wind, and othertypes of unconventional energy, in the conditionsin which electric motors have been instead ofinternal combustion in public transport, but morerecently they have entered in the cars world
(Honda has produced a vehicle that uses acompact electric motor and electricity consumedby the battery is restored by a system that uses anelectric generator with hydrogen combustion incells, so we have a car that burns hydrogen, but
has an electric motor), which is the role andprospects which have internal combustion enginestype Otto or Diesel?
Internal combustion engines in four-stroke
(Otto, Diesel) are robust, dynamic, compact,powerful, reliable, economic, autonomous,independent and will be increasingly clean.
Let's look at just remember that any electric
motor that destroy ozone in the atmosphereneeded our planet by sparks emitted by collectingbrushes. Immediate consequence is that if we onlyuse electric motors in all sectors, well haveproblems with higher ozone shield that protects
our planet and without which no life could existon Earth.
Magnetic motors (combined with theelectromagnetic) are just in the beginning, butthey offer us a good perspective, especially in the
aeronautics industry.Probably at the beginning they will not be used
to act as a direct transmission, but will generateelectricity that will fill the battery that willactually feed the engine (probably an electric
motor).The Otto engines or those with internal
combustion in general, will have to adapt tohydrogen fuel.
It is composed of the basic (hydrogen) canextract industrially, practically from any item (or
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2
combination) through nuclear, chemical, photonic
by radiation, by burning, etc... (Most easilyhydrogen can be extracted from water by breaking
up into constituent elements, hydrogen andoxygen; by burning hydrogen one obtains wateragain that restores a circuit in nature, with no
losses and no pollution).Hydrogen must be stored in reservoirs cell (a
honeycomb) for there is no danger of explosion;the best would be if we could breaking up waterdirectly on the vehicle, in which case the reservoirwould feed water (and there were announcedsome successful).
As a backup, there are trees that can donate afuel oil, which could be planted on the extendedzone, or directly in the consumer court. Withmany years ago, Professor Melvin Calvin,(Berkeley University), discovered that Euphoratree, a rare species, contained in its trunk a liquidthat has the same characteristics as raw oil. Thesame professor discovered on the territory ofBrazil, a tree which contains in its trunk a fuelwith properties similar to diesel.
During a journey in Brazil, the natives drivenhim (Professor Calvin) to a tree called by them
"Copa-Iba".At the time of boring the tree trunk, from it to
begin flow a gold liquid, which was used asindigenous raw material base for the preparationof perfumes or, in concentrated form, as a balm.
Nobody see that it is a pure fuel that can be useddirectly by diesel engines.
Calvin said that after he poured the liquidextracted from the tree trunk directly into the tankof his car (equipped with a diesel), engine
functioned irreproachable.In Brazil the tree is fairly widespread. It could
be adapted in other areas of the world, planted inthe forests, and the courts of people.
From a jagged tree is filled about half of thetank; one covers the slash and it is not open until
after six months; it means that having 12 trees in acourtyard, a man can fill monthly a tank with thenew natural diesel fuel.
In some countries (USA, Brazil, Germany)producing alcohol or vegetable oils, for their useas fuel.
In the future, aircraft will use ion engines,magnetic, laser or various micro particlesaccelerated. Now, and the life of the jet enginebegin to end.
Even in these conditions internal combustionengines will be maintained in land vehicles (at
least), for power, reliability and especially theirdynamics. Thermal engine efficiency is still lowand, about one third of the engine power is lost
just by the distribution mechanism. Mechanical
efficiency of cam mechanisms was about 4-8%. Inthe past 20 years, managed to increase to about
14-18%, and now is the time to pick it up again atup to 60%. This is the main objective of thispaper.
2. Presenting a Dynamic Model, with one
Grade of Freedom, with Variable
Internal Amortization
2.1.Determining the Amortization
Coefficient of the Mechanism
Starting with the kinematical schema of theclassical valve gear mechanism (see the Figure 1),
one creates the translating dynamic model, with asingle degree of freedom (with a single mass),with variable internal amortization (see the Figure2), having the motion equation (1) [3, 13].
The formula (1) is just a Newton equation,where the sum of forces on a single element is 0.
0)( FxcxkxyKxM (1)
5 1
2
3
4
A
B
C
D
C0
O
Fig. 1. The Kinematical schema of the classical
valve gear mechanism.
The Newton equation (1) can be written in theform (2).
)()( 0 xkFxyKxcxM (2)
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M M
k
kx F
F(t) c .
cx
xx(t)
K(y-x)K
y(t)
cam
Fig. 2. Dynamic Model with a Single Liberty, with
variable internal amortization.
The differential equation, Lagrange, can bewritten in the form (3).
rm FFxdt
dMxM 2
1 (3)
Comparing the two equations, (2 and 3), oneidentifies the coefficients and one obtains theresistant force (4), the motor force (5) and thecoefficient of internal amortization (6). One cansee that the internal amortization coefficient, c, isa variable.
)( 000 xxkxkxkxkFFr (4)
)()( xsKxyKFm (5)
dt
dMc 2
1 (6)
One places the variable coefficient, c, (see therelation 6), in the Newton equation (form 1 or 2)
and obtains the equation (7).
0)(
2
1FyKxkKx
dt
dMxM (7)
The reduced mass can be written in the form(8), (the reduced mass of the system, reduced atthe valve).
244
211
22325
)()(
)()(
xJ
xJ
x
ymmmM
(8)
With the following notations:
m2 =the mass of the tappet (of the valve lifter); m3=the mass of the valve push rod; m5 =the valvemass; J1 =the inertia mechanical moment of the
cam; J4 =the inertia mechanical moment of the
valve rocker; 2y =the tappet velocity, or the
second movement-low, imposed by the camsprofile; x =the real (dynamic) valve velocity.
If one notes with i=i25, the ratio of transmission
tappet-valve, given from the valve rocker, thetheoretically velocity of the valve, y , (the tappet
velocity reduced at the valve), takes the form (9),
where the ratio of transmission, i, is given fromthe formula (10).
i
yyy 25
(9)
DC
CCi0
0 (10)
One can write the following relations (11-16),where y is the reduced velocity forced at thetappet by the cams profile. With the relations (10,13, 14, 16) the reduced mass (8), can be written inthe forms (1719).
'1 xx (11)
''21 xx (12)
'1'
212 yiyy (13)
'
1
'1
11
xxx
(14)
DC
y
DC
CC
CC
y
CC
iy
CC
y
CC
y
0
1
0
0
0
1
0
1
0
'
21
0
2
4
''
'.
(15)
'
'1
'
'
010
14
x
y
DCxDC
y
x
..(16)
2
0
4
2
1
2
325
)'
'1()
'
1(
)'
'()(
x
y
DCJ
xJ
x
yimmmM
(17)
2
1
2
2
0
4
32
2
5
)'
1()
'
'(])(
)([
xJ
x
y
DC
J
mmimM
(18)
2
1
2
5 )'
1
()'
'
(* xJx
y
mmM ..(19)
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4
It derives dM/d and obtains the relations (2022).
)'
''
'
''()'
'(2)'
'''''('
'2
'
)''''''(
'
'2])
'
'[(
2
2
2
2
x
x
y
y
x
y
x
yxyx
y
x
yxxy
x
y
d
x
yd
...(20)
32
2
'
''2
'
''
'
2])'
1[(
x
x
x
x
xd
xd
(21)
31
2
'
''2)'
''
'
''()'
'(*2
x
xJ
x
x
y
y
x
ym
d
dM
...(22)
The relation (6) can be written in form (23) andwith relation (22), its taking the forms (2425).
d
dMc 2
(23)
}'
'')'
''
'
''()
'
'(
])(
)({[
31
2
2
0
432
2
x
xJ
x
x
y
y
x
y
DC
Jmmic
(24)
]''')
'''
'''()
''(*[
312
xxJ
xx
yy
xymc (25)
With the notation (26):
2
0
4
32
2
)()(*
DC
Jmmim (26)
2.2.Determining the Movement Equations
With the relations (19, 12, 25, 11) the equation
(2) take the forms (27, 28, 29, 30 and 31) [13]:
0
2 )(''' FyKxkKxcxM (27)
03
''
1
2'
'
''
'
''2*'22''2
'1
''2*2
5
''2
)('
)()'
'()
1(
)'
'(
FyKxkKx
x
Jx
x
x
y
y
x
ymxx
xJ
xx
ymmx
(28)
0
*2
2*22*2
5
2
)('
'''
'')'
'()
'
'(''''
FyKxkKx
yym
xx
ym
x
yxmxm
(29)
0
''*2''
5
2
'
')( FKy
x
yymxkKxm
(30)
0
*
5
2)()
'
'''''( FyKxkKx
yymxm
(31)
The exact equation (31) can be approximated
at the form (32) with xy.
0*
52 )()''''( FyKxkKymxm
(32)
With the following notations: y=s, y=s,y=s, y=s, the equation (32) takes theapproximate form (33) and the complete equation
(31) takes the exact form (34).
0
*
5
2)()''''( FsKxkKsmxm
(33)
052 )()
''''*''( FsKxkK
xssmxm
(34)
Solving the Differential Equation by Direct
Integration and Obtaining the Mother
Equation
One integrates the equation (31) directly. Oneprepares the equation (31) for the integration.First, one writes (31) in form (35) [13].
I
III
TII
Sx
yymxm
xkyKxkK
2*
2*
0)(
(35)
The equation (35), can be amplified by x andone obtains the relation (36).
III
T
III
S
III
yymxxm
xxkxyKxxkK
2*2*
0)(
(36)
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Now, one replaces the term K.y.x
with IykK
KyK
, (taken in calculation the
statically assumption, Fm=Fr) and one obtains the
form (37).
III
T
III
S
III
yymxxm
xxkyykK
KxxkK
2*2*
0
2
)(
(37)
One integrates directly the equation (37) and
one obtains the mother equation (38).
Cy
mx
m
xxky
kK
KxkK
TS
2
'
2
'
22)(
22*
22*
0
222
(38)
With the initial condition, at the =0, y=y=0and x=x=0, one obtains for the constant ofintegration, C the value 0. In this case the
equation (38), takes the form (39).
2
'
2
'
22)(
22*
22*
0
222
ym
xm
xxky
kK
KxkK
TS
(39)
The equation (39) can be put in the form (40),
if one divides it with the2
kK .
0)(
'
'2
2
2
22
2*
2
2*
02
ykK
Ky
kK
m
xkK
mx
kK
xkx
T
S
(40)
The mother equation (40), take the form (41),
if one notes: '' ykK
Kx
, (the static
assumption, Fm=Fr).
0')(
)(
)(2
22
**
2
2
2
2
2
02
ykK
mm
kK
K
ykK
Kx
kK
xkx
TS
(41)
Solving the Mother Equation (41) Directly
The equation (41) is a two degree equation in
x; One determines directly, (42-43) and X1,2(44) [13].
22
*
2
2
*
2
22
0 ')(
)(
)(
)()(y
kK
mkK
Km
kK
sKxk TS
(42)
22
*
2
2*
2
22
0 )'()(
)(
)(
)()(Ds
kK
mkK
Km
kK
Kskx TS
(43)
kK
xkX 02,1 (44)
Physically, just the positive solution is valid
(see the relation 45).
kK
xkX
0 (45)
Solving the Mother Equation (41) with
Finished Differences
One can solve the mother equation (41) using
the finished differences [13]. One notes:
XsX (46)
With the notation (46) placed in the mother
equation (41), it obtains the equation (47).
0')(
)(
)(
222)(
22
**
2
2
2
2
2
0022
ykK
mmkK
K
skK
K
XkK
xks
kK
xkXsXs
TS
(47)
The equation (47) is a two degree equation in
X, which can be solved directly with (49) and
X1,2, (50), or transformed in a single degree
equation in X, with (X)20, solved by the
relation (48).
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20
22**2
0
22
)()(2
)'(])([)(2)2(
)1(
kKkK
xks
DsmkKmkK
KskKkxskKk
X
TS
(48)
2
22**2
2
0
222
)(
)'(])([
kK
DsmkKmkK
KxksK TS
(49)
)( 0
kK
xksX
(50)
2.3.Mechanism with Rotary Cam and
Translated Tappet with Roll
First, one presents an original method todetermine the efficiency at the mechanism withrotary cam and translated follower with roll [5].
With this occasion it presents and the forcesand the velocities as well (Figure 3).
The pressure angle (Figure 3), is determinedby relations (1.5-1.6).
We can write the next forces, speeds andpowers (1.13-1.18).
Fm(vm) is perpendicular to the vector rAat A.Fmis divided into Fa(the sliding force) and Fn
(the normal force). Fn is divided too, into Fi (the
bending force) and Fu (the useful force). Themomentary dynamic efficiency can be obtained
from relation (1.18).
0A
A
B
A-
Fn, vn
Fm, vm
Fa, va
Fi, viFn, vn
Fu, v2
B
B0
A0
A
O
x
e
s0
rb
r0
rA
rB
s
n
C
rb
Fig. 3. Forces and velocities at the cam with
translated follower with roll.
The written relations are the following.
2
0
22
B s)(ser ... (1.1)
2
BB rr ...(1.2)
B
Bre sincos ...(1.3)
B
Br
ss 0cossin ...(1.4)
22
0
0
)'()(cos
esss
ss
...(1.5)
22
0 )'()(
'sin
esss
es
...(1.6)
sinsincoscos)cos( ...(1.7)
)cos(2
)cos()sin(
222
2
0
22
BbbBA
bbA
rrrrr
rssrer
...(1.8)
A
b
A
A
b
A
r
re
esssr
esressse
sin
cos
)'()(
)'()'()(cos
22
0
22
0
...(1.9)
A
bA
A
b
A
r
rss
esssr
resssss
cossin
)'()(
])'()([)(sin
0
22
0
22
00
...(1.10)
cos'
)cos(
)'()(
')()cos( 22
0
0
A
A
A
A
r
s
esssr
sss
...(1.11)
2cos'
cos)cos( A
Ar
s ...(1.12)
)sin(
)sin(
Ama
Ama
FF
vv ...(1.13)
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)cos(
)cos(
Amn
Amn
FF
vv ...(1.14)
sin
sin
ni
ni
FF
vv ...(1.15)
cos)cos(cos
cos)cos(cos2
Amnu
Amn
FFF
vvv
...(1.16)
mmc
Ammuu
vFP
vFvFP 222 cos)(cos
...(1.17)
4
2
2
222
22
cos'
]cos'[]cos)[cos(
cos)(cos
A
i
A
Ai
mm
Amm
c
ui
r
s
r
s
vF
vF
P
P
...(1.18)
bB rrr 00 (1.19)
22
00
ers B (1.20)
0
0cosBr
e (1.21)
0
0
0sinBr
s (1.22)
2.4.The Relations to Design the Profile
Now one determines the profile of the cam(relations 1.23-1.28).
0 A (1.23)
00 sinsincoscoscos AA
(1.24)
00 sincoscossinsin AA (1.25)
A (1.26)
sinsincoscoscos A (1.27)
cossincossinsin A (1.28)
2.5.The Exact Kinematics of B Module
From the triangle OCB (fig. 3) the length rB
(OB) and the complementary angles B (COB)
and (CBO) are determined by the relation (1.1-1.4).
From the general triangle OAB, where oneknows OB, AB, and the angle between them, B
(ABO, which is the sum of with ), the length
OA and the angle (AOB) can be determinedwith the relations (1.7-1.8, 1.29-1.31):
BA
bBA
rr
rrr
2
cos222
(1.29)
cossincossin)sin( ...(1.30)
)sin(sin A
b
r
r (1.31)
With B and we can deduce now A and
A (the relations 1.32-1.33):
BA (1.32)
BA (1.33)
From (1.3) one obtains B (1.37), (see 1.34-
1.37) where Br (1.36) can be deduced from (1.1).
Then, (1.38) will be obtained from (1.29):
2sin
B
B
BBr
re
(1.34)
2
0 )( B
BB
Brss
rre
(1.35)
sssrr
sssrr
BB
BB
)(
)(22
0
0 (1.36)
22
0
0
)(
)(
BB
Br
se
rss
ssse
(1.37)
BBAABA
BABA
rrrrrr
rrrr
22sin2
cos2cos2
(1.38)
From (1.38) one writes (1.43), but it is
necessary to obtain first Ar (1.39) fromexpression (1.8):
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)()sin(2
)cos(222
Bb
BbBBAA
rr
rrrrrr
(1.39)
To solve (1.39) we need the derivatives
(1.40 and 1.41) and (1.42).
22
0
0
)'()(
)'(')('''
esss
essess
(1.40)
' (1.41)
2
B
Br
se
(1.42)
Now we can determine
(1.43), A
(1.33)and A
(1.44):
sin
coscos
BA
BBAABABA
rr
rrrrrrrr
(1.43)
AA (1.44)
We write cos A and sin A (1.9-1.10):
Further, we can obtain the expression cos(A-
) (1.11), and cos(A-).cos(1.12).
Finally the forces and the velocities arededuced as follows (1.13-1.16):
2.6.Determining the Efficiency of the
Module B
With the relationships (1.17-1.18) we candetermine the powers and the momentarymechanical efficiency [14].
Determining the (Dynamic) Transmission
Function D, for the Module B
The followers velocity (1.16) can be writteninto the form (1.45).
22
22
2
cos'cos'
cos'
cos'
cos)cos(cos
ss
r
sr
r
sv
vvv
IAA
A
AA
A
m
Amn
(1.45)
With the relationships (1.45) and (1.46) we
determine the transmission function (the dynamicmodulus), D (1.47):
Dsv '2 (1.46)
2cos IAD (1.47)
Expression cos2is known (1.48):
22
0
2
02
)'()(
)(cos
esss
ss
(1.48)
The expression of the A (1.49) is moredifficult.
]}')[(2
)'()(
])/{[(
/])'()/[(]})'(
)()'(')(''[
)'()(])'(
){[(])'()(
')[(
22
0
22
0
222
0
22
0
2
2
00
22
0
2
2
0
22
0
22
0
seessr
esss
ress
essses
ssesssssr
essses
ssesss
rseess
b
b
b
b
I
A
(1.49)
We will determine by its expressions (1.50-1.51):
22
0
220
22
0
22
0
22
0
)'()(
]')[(
)'()(
)'()(])[(
cos
esssrr
seessr
esssrr
esssess
BA
b
BA
(1.50)
22
0
0
)'()(
')(sin
esssrr
sssr
BA
b
(1.51)
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The Dynamics of Distribution Mechanisms
with Translated Follower with Roll
For the dynamics of the Module B therelationships (49-50) are used in the forms (1.52-1.54), where D is determined from (1.47).
][2
'
])(
[2
)(
2
0
2
2**
2
2
02
2
2
kK
kxs
ykK
mmkK
K
skK
kxs
kK
kKk
X
TS
(1.52)
][2
)'(
])(
[2
)(
2
0
2
2**
2
2
02
2
2
kK
kxs
sDkK
mmkK
K
skK
kxs
kK
kKk
X
TS
(1.53)
XsX (1.54)
2.7.The Dynamic Analysis of the Module B
It presents now the dynamics of the module Bfor some knownmovement laws.
We begin with the classical law SIN (see thediagram in Figure 4); A speed rotation n=5500[rot/min], for a maxim theoretical displacement of
the valve h=6 [mm] is used.Thephaseangle is u=c=65 [degree]; the ray
of the basic circle is r0=13 [mm].For the ray of the roll the value rb=13 [mm]
has been adopted.
Fig. 4. The dynamic analysis of the module B. The
law SIN, n=550 rpm, u=650
, r0=13 [mm], rb=13[mm], hT=6 [mm], e=0 [mm],k=30 [N/mm], and
x0=20 [mm].
Fig.5. The profile SIN at the module B. n=5500 rpm
u=650, r0=13 [mm], rb=13 [mm], hT=6 [mm].
The dynamics are better than for the classical
module C. For a phase angle of just 65 degrees theaccelerations have the same values as for theclassical module C for arelaxedphase (750-800).
In Figure 5 we can see the cams profile. Ituses the profile sin, a rotation speed n=5500 rpm,
and u=650, r0=13 [mm], rb=13 [mm], hT=6 [mm].
The law COS can be seen in the Figures 6 and
7. In the Figure 6 is presented the dynamicanalyze of the profile cos, and its profile designcan be seen in the Figure 7.
The principal parameters are:
Law COS, n=5500 rpm, u=650, r0=13 [mm],
rb=6 [mm], hT=6 [mm], =10.5%.
Fig. 6. The dynamic analysis of the module B. LawCOS, n=5500 rpm, u=65
0, r0=13 [mm], rb=6 [mm],
hT=6 [mm], =10.5%.
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Fig. 7. The profile COS at the module B, n=5500
rpm, u=650
, r0=13 [mm], rb=6 [mm], hT=6 [mm].
Fig. 8. The dynamic analysis. Law C4P1-0, n=5500
rpm, u=800, r0=13 [mm], rb=6 [mm], hT=6 [mm].
In the figure 8 the law C4P, created by the
author, is analyzed dynamic. The vibrations arediminished, the noises are limited, the effectivedisplacement of the valve is increased, smax=5.37
[mm].
Fig. 9. The profile C4P of the module B.
The efficiency has a good value =8.6%. In theFigure 9 the profile of C4P law is presented.
It starts at the law C4P with n=5500 [rpm], butfor this law the rotation velocity can increase tohigh values of 30000-40000 [rpm] (see the Figure10).
Fig. 10. The dynamic analysis of the module B. Law
C4P1-5, n=40000 rpm.
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2.8.The New Cam Synthesis
The rotary cam with translated follower withroll (Figure 3 or 13), is synthesized dynamic bythe new next relationships.
It has exchanged the rotation sense from the
Figure 1 to Figure 11, from the clockwise to thecounter-clockwise.
First, one determines the mass moment ofinertia (mechanical) of the mechanism, reduced tothe element of rotation, ie cam (basically usingkinetic energy conservation, system 2.1).
2
22
0
2
0
2
2
00
2
0
2*
2
0
22
2
0
2
0
2
0
2
0
2
00
22
0
*
22
0
22
0
2
02
0
222
22
0
00
22
0
2
0
222
0
2
0
222
0
222
0
2222222
2
''
'
2
122
2
1
8
22
22
2
1
16
1
4
1
2
1
'
'2
'
2
'2
'
'2
cossin2
cos2cos
sin2sin
2
1
smesss
sseserM
sMssMrrrrMJ
hm
ehh
s
hse
he
rM
hMhsMrrrrMJ
esss
eser
esss
ssrssrer
esss
ssssr
esss
eserssrer
sserssrer
ssrrss
rereyxrR
RMJ
Tbc
ccbbc
Tbc
ccbbcm
b
bbA
b
bbA
bbA
bb
bbAAA
ccama
...(2.1)
We considered the law of motion of the tappetclassic version already used the cosine law (bothascending and descending).
The angular velocity is a function of the cam
position () but also its rotation speed (2.2).
Where mis the nominal angular velocity of camand express at the distribution mechanisms basedon the motor shaft speed (2.3).
2
*
*2
m
m
J
J ...(2.2)
60260
2
6022
nn
n
motor
ccm
...(2.3)
We start the simulation with a classical law ofmotion, namely the cosine law. To climb cosinelaw system is expressed by the relationships (2.4).
uu
r
uu
r
uu
r
u
hs
has
hvs
hhs
sin2
'''
cos2
''
sin2
'
cos22
3
3
2
2
...(2.4)
Where takes values from 0 to u.
Jmaxoccurs for =u/2.With the relation (2.5) is expressed the first
derivative of the reduced mechanical moment ofinertia. It is necessary to determine the angularacceleration (2.6).
2/3220
0
2
0
2
2/322
0
22
00
0
*'
'
'''''
'
''2''
'''2''
esss
sesssssseserM
esss
essssssserM
ssmssMssMJ
bc
bc
Tcc
...(2.5)
Differentiating the formula (2.2), against time,is obtained the angular acceleration expression(2.6).
*
*'2
2 J
J
...(2.6)
Relations (2.2) and (2.6) a general nature andare basically two original equations of motion,crucial for mechanical mechanisms.
For a rotary cam and translated tappet with rollmechanism (without valve), dynamic movementtappet is expressed by equation (2.7), which is an
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original dynamic equation deduced for the
distribution mechanism (50) and now bycanceling the valve mass, will customize and
reaching form below (2.7).
kK
xkskK
skKxksKkksmkK
sx
T
02
0
2222
)(2
)(2)2(')(
...(2.7)
Where x is the dynamic movement of thepusher, while s is its normal, kinematicsmovement. K is the spring constant of the system,
and k is the spring constant of the tappet spring.It note, with x0the tappet spring preload, with
mT the mass of the tappet, with the angularrotation speed of the cam (or camshaft), where sis the first derivative in function of of the tappet
movement, s. Differentiating twice successively,the expression (2.7) in the angle , we obtain areduced tappet speed (equation 2.8), and reducedtappet acceleration (2.9).
2
02
0
0
22
0
2222
2
''
'
'2'22'''2
)(2)2(')(
kK
kxskK
Msx
sNkK
kxs
skKkxsskKkssmkKM
skKxksKkksmkKN
T
T
(2.8)
3
02
00
0
22
22
0
0
22
0
2222
2
'2''
''''
''2'''22
''''''2
'
'2'22'''2
)(2)2(')(
kK
kxskK
sMkK
kxssN
kK
kxsO
sx
skKxksssKkk
sssmkKO
sNkK
kxs
skKkxsskKkssmkKM
skKxksKkksmkKN
T
T
T
(2.9)
Further the acceleration of the tappet can be
determined directly real (dynamic) using therelation (2.10).
''' 2 xxx ...(2.10)
3. New Dynamic Synthesis
Give the following parameters:r0=0.013 [m]; rb=0.005 [m]; h=0.008 [m]; e=0.01
[m]; x0=0.03 [m]; u=/2; c=/2; K=5000000[N/m]; k=20000 [N/m]; mT=0.1 [kg]; Mc=0.2[kg]; nmotor=5500 [rot/min].
To sum up dynamically based on a computer
program, you can vary the input data until thecorresponding acceleration is obtained (see Figure11). It then summarizes the corresponding cam
profile (Figure 12) using the relations (2.11).
Fig. 11. Dynamic diagram to the rotary cam with
translated follower with roll.
coscossinsin
sincoscossin
cossin
sincos
cos
sin
0
0
0
bbC
bbC
TTC
TTC
bT
bT
rssrey
rssrex
yxy
yxx
rssy
rex
...(2.11)
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Fig. 12. The cam profile to the rotary cam with
translated follower with roll; rb=0.003 [m]; e=0.003
[m]; h=0.006 [m]; r0=0.013 [m]; 0=/2 [rad];.
3.1.
The New Geometry of the Rotary Camand the Translated Follower with Roll
Now, we shall see the geometry of a rotarycam with translated follower with roll (Figure 13).The cam rotation sense is positive (trigonometric).
We can make the geometrical synthesis of thecam profile with the help of the cinematics of themechanism. One uses as well the reduced speed,s. OA=r=rA; r
2=rA2
It establishes a system fixed Cartesian, xOy =xfOyf, and a mobil Cartesian system, xOy =
xmOymfixed with the cam.From the lower position 0, the tappet, pushed
by cam, uplifts to a general position, when the
cam rotates with the angle. The contact point A,
go from Ai0 to A
0(on the cam), and to A (on the
tappet). The position angle of the point A from the
tappet is f, and from the cam is m. We candetermine the coordinates of the point A from thetappet (2.12), and from the cam (2.13).
ffAbfAT
ffAb
f
AT
rrrssyy
rrrexx
sinsincos
coscossin
0
...(2.12)
sinsincoscossincos
cossincossinsinsin
sincoscossinsincos
sinsincoscoscoscos
0
0
bbTT
fffmA
m
Ac
bbTT
fffmA
m
Ac
rerssxy
rrrryy
rssreyx
rrrrxx
(2.13)
f
m
A
0
iA
0AO
fx
fy
mx
0B
B
e
s
0s
r
0r
0r
br
br
Br
0
Fig. 13. The geometry of the rotary cam with
translated follower with roll.
One uses and the next relationships (2.14),
where the pressure angle was obtained with theclassic Antonescu P. method [2].
22
0
22
0
0
22
00
'
'sin
'cos
esss
es
esss
ss
errs b
...(2.14)
3.2.Determining the Forces, the Velocities
and the Efficiency
The driving force Fm, perpendicular on r in A,is divided in two components: Fn, the normalforce, and Fa, a force of slipping. Fn is divided, aswell, in two components: FTis the transmitted (theutile) force, and FR is a radial force which bend
the tappet (see 2.15, and the Figure 14).
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cossin2
cossin
;;2
cos
;22
;
coscoscoscos
coscoscoscos
coscoscos
coscoscos
cos
cos
0
2
0
22
2
0
222
2
0
2222
222
sserssrerr
rssreyxr
sserrr
rrrA
AA
vF
vF
vF
vF
P
P
vvv
FFF
vv
FF
bbA
bbAfAf
B
b
Bb
mm
mm
mm
TT
c
ui
mnT
mnT
mn
mn
(2.15)
f
m
A
0
iA
0A
O
fx
fy
mx
0B
B
e
s
0s
r
0r
0r
br
br
Br
0
TF
RF
nF
nF
mF
aF
Fig.14. Forces and velocities of the rotary cam withtranslated follower with roll.
3.3.New Geometro-Kinematics Synthesis
For a good work one proposes to make a newgeometric and kinematics synthesis of the camprofile, using some new relationships for thepressure angle delta (2.16). The new synthesisrelations already presented (2.12 and 2.13) willuse delta pressure angle, deduced now with new
relationship (2.16).
ffAb
f
AT
ffAb
f
AT
rrrssyy
rrrexx
sinsincos
coscossin
0
...(2.12)
sinsincoscossincos
cossincossinsinsin
sincoscossinsincos
sinsincoscoscoscos
0
0
bbTT
fffmA
m
Ac
bbTT
fffmA
m
Ac
rerssxy
rrrryy
rssreyx
rrrrxx
(2.13)
One uses and the next relationships (where the
pressure angle was obtained with the newmethod):
][2
'2'4'4arccossinsin
][2
'2'4'4arccos
cosarccos
][2
'2'4'4cos
22
0
22
00
2
0
22
0
22
00
2
0
22
0
22
00
2
0
22
00
ess
sesesssssss
ess
sesesssssss
ess
sesesssssss
errs b
...(2.16)
The new profile can be seen in the Figure 15.
Fig. 15. The new cam profile to the rotary cam with
translated follower with roll; rb=0.003 [m]; e=0.003
[m]; h=0.006 [m]; r0=0.013 [m]; 0=/2 [rad];
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3.4.Demonstration (Explication)
The original relationships (2.16) have beendeduced by the expressions (2.17).
Classical method uses to the geometricsynthesis and the reduced tappet velocity, and in
this mode the geometric classic method become ageometric and kinematic synthesis method. Thenew geometric synthesis method uses just thegeometric parameters (without velocities), but oneutilizes and a condition to realize at the tapped thevelocities predicted by the tapped movement lawsimposed by the cam profile.
][2
'2'4'4cos
][2
'4'2'2cos
0'cos'2cos
cos'2cos'coscos
cos'cos1cos
coscossin'cossin
cos
'
cossincossincossinsin
sincos
'sin
cos
'
sinsin
sincos
'
sin
2
cos
2
coscos
22;;
2
coscos'coscos
22
0
22
00
2
0
22
0
22
0
222
0
2
02
222
0
422
0
242242
0
22
0
22
0
2
00
0
ess
sesesssssss
ess
essssessesss
ssessess
seesssss
esss
esssr
ess
r
s
r
e
r
ssBBB
Br
sB
r
r
r
s
Br
rA
Ar
s
AAA
AA
rsrs
BB
BB
BA
B
A
A
B
A
AA
...(2.17)
Then, it makes the dynamic analyze for theimposed cam profile, and one modify the cam
profile geometric parameters to determine a gooddynamic response (functionality). In this mode it
realizes the dynamic synthesis of the cam, and weobtain a normal functionality. The synthesis wasmade using the natural geometro-kinematicsparameters (of cam mechanism). It follows the
proper functioning dynamics. We will optimizeand the couple cam-pusher efficiency. Forces,velocities and accelerations are also limited.
3.5.Increasing the mechanical efficiency at
the Rotary Cam and Translated
Follower with Roll
The used law is the classical law (2.4), cosinelaw.
The synthesis of the cam profile can be madewith the relationships (3.1) when the cam rotatesclockwise and with the expressions from the
system (3.2) when the cam rotates
counterclockwise (trigonometric).
sinsincoscos
sincoscossin
0
0
bbC
bbC
rerssy
rssrex
(3.1)
sinsincoscos
sincoscossin
0
0
bbc
bbc
rerssy
rssrex
...(3.2)
The r0(the radius of the base circle of the cam)is 0.013 [m]. The h (the maximum displacement
of the tappet) is 0.020 [m]. The angle of lift, uis/3 [rad]. The radius of the tappet roll is rb=0.002[m]. The misalignment is e=0 [m]. The cosine
profile can be seen in the fig. 16.
Fig. 16. The cosine profile at the cam with
translated follower with roll; r0=13[mm],
h=20[mm], u=/3[rad], rb=2[mm], e=0[mm].
The obtained mechanical yield (obtained byintegrating the instantaneous efficiencythroughout the climb and descent) is 0.39 or
=39%. The dynamic diagram can be seen in thefig. 17 (the dynamic setting are partial normal).Valve spring preload 9 cm no longer poses today.
Instead, achieve a long arc very hard(k=500000[N/m]), require special technologicalknowledge.
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Fig. 17. The dynamic diagram at the cosine
profile at the cam with translated follower with
roll; r0=13[mm]; h=20[mm]; u=/3[rad];
rb=2[mm]; e=0[mm]; n=5500[rpm]; x0=9[cm];
k=500[kN/m]
It tries increase the yield [8-9, 15-16]; angle of
climb is halved u=/6[rad] (see the profile in theFig. 18).
The r0(the radius of the base circle of the cam)is 0.015 [m]. The h (the maximum displacementof the tappet) is 0.010 [m]. The angle of lift, uis
/6 [rad]. The radius of the tappet roll is rb=0.002[m]. The misalignment is e=0 [m]. The cosineprofile can be seen in the Fig. 18.
Fig. 18. The cosine profile at the cam with
translated follower with roll; r0=15[mm],
h=10[mm], u=/6[rad], rb=2[mm], e=0[mm].
The obtained mechanical yield (obtained by
integrating the instantaneous efficiencythroughout the climb and descent) is 0.428 or
=43%. The dynamic diagram can be seen in thefig. 19 (the dynamic setting are not normal).Valve spring preload 20 cm no longer poses
today. Instead, achieve a long arc very-very hard(k=1500000[N/m]), require special technologicalknowledge.
Fig. 19. The dynamic diagram at the cosine profile
at the cam with translated follower with roll;
r0=15[mm]; h=10[mm]; u=/6[rad]; rb=2[mm];
e=0[mm]; n=5500[rpm]; x0=20[cm]; k=1500[kN/m]
Camshaft runs at a shaft speed halved (nc=n/2).
If we more reduce camshaft speed by threetimes (nc=n/6), we can reduce and the preload ofthe valve spring (x0=5[cm]); see the dynamicdiagram in the Fig. 20. However, in this case, thecam profile should be tripled (see the Fig. 21).
-1400
-1200
-1000
-800
-600
-400
-200
0
200
400
600
0 50 100 150 200 250 300 350 400
xpp [m/s2]
xpp [m/s2]
-1400
-1200
-1000
-800
-600
-400
-200
0
200
400
600
0 50 100 150 200 250 300
xpp [m/s2]
-1400
-1200
-1000
-800
-600
-400
-200
0
200
400
600
0 50 100 150
Fig. 20. The dynamic diagram at the cosine tripled
profile at the cam with translated follower with
roll; r0=15[mm]; h=10[mm]; u=/6[rad];rb=2[mm]; e=0[mm]; n=5500[rpm]; x0=5[cm];
k=1500[kN/m].
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Fig. 21. The cosine tripled profile at the cam withtranslated follower with roll; r0=15[mm],
h=10[mm], u=/6[rad], rb=2[mm], e=0[mm].
It tries increase the yield again; angle of climb
is reduced to the value u=/8[rad].
The r0(the radius of the base circle of the cam)is 0.013 [m].
The h (the maximum displacement of thetappet) is 0.009 [m].
The angle of lift, uis /8 [rad].The radius of the tappet roll is rb=0.002 [m].The misalignment is e=0 [m]. The cosine
profile can be seen in the fig. 22.
Fig. 22. The cosine profile at the cam with
translated follower with roll; r0=13[mm], h=9[mm],
u=/8[rad], rb=2[mm], e=0[mm].
The obtained mechanical yield (obtained byintegrating the instantaneous efficiency
throughout the climb and descent) is 0.538 or=54%. The dynamic diagram can be seen in thefig. 23 (the dynamic setting are not normal).Valve spring preload 30 cm no longer posestoday. Instead, achieve a long arc very-very hard(k=1600000[N/m]), require special technologicalknowledge.
Fig. 23. The dynamic diagram at the cosine profile
at the cam with translated follower with roll;
r0=13[mm]; h=9[mm]; u=/8[rad]; rb=2[mm];
e=0[mm]; n=5000[rpm]; x0=30[cm]; k=1600[kN/m]
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Camshaft runs at a shaft speed halved (nc=n/2).
If we more reduce camshaft speed by four times(nc=n/8), we can reduce and the preload of the
valve spring, x0=9[cm] and the elastic constant ofthe valve spring, k=15000[N/m]; see the dynamicdiagram in the Fig. 24. However, in this case, the
cam profile should be fourfold (see the Fig. 25).
-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
0 50 100 150 200 250 300 350 400
xpp [m/s2]
xpp [m/s2]
-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
0 50 100 150 200 250 300 350 400
xpp [m/s2]
-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
0 50 100 150 200
xpp [m/s2]
-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
0 50 100 150 200 250 300
xpp [m/s2]
Fig. 24. The dynamic diagram at the cosine fourfold
profile at the cam with translated follower with roll;
r0=13[mm]; h=9[mm]; u=/8[rad]; rb=2[mm];
e=0[mm]; n=5000[rpm]; x0=9[cm]; k=15[kN/m]
Fig. 25. The cosine fourfold profile at the cam with
translated follower with roll; r0=13[mm], h=9[mm],
u=/8[rad], rb=2[mm], e=0[mm].
With the same angle of climb u=/8[rad], canincrease performance even further, if the sizetappet race take a greater value (h=12[mm]). Ther0 (the radius of the base circle of the cam) is0.013 [m].
The h (the maximum displacement of the
tappet) is 0.012 [m]. The angle of lift, u is /8[rad]. The radius of the tappet roll is rb=0.002 [m].The misalignment is e=0 [m]. The cosine profile
can be seen in the fig. 26.
Fig. 26. The cosine profile at the cam with
translated follower with roll; r0=13[mm],
h=12[mm], u=/8[rad], rb=2[mm], e=0[mm].
For correct operation it is necessary todecrease the speed of the camshaft four times, andall four times multiplication of the cam profile.Camshaft runs at a shaft speed halved (nc=n/2). Ifwe more reduce camshaft speed by four times
(nc=n/8), we can reduce and the preload of thevalve spring, x0=9[cm]. The elastic constant of thevalve spring is k=1500000[N/m]. See the dynamicdiagram in the Fig. 27. However, in this case, thecam profile should be fourfold. The obtained
mechanical yield is 0.60 or =60%.
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-2000
-1500
-1000
-500
0
500
0 50 100 150 200 250 300 350 400
xpp [m/s2]
xpp [m/s2]
-2000
-1500
-1000
-500
0
500
0 50 100 150 200 250 300 350 400
xpp [m/s2]
-2000
-1500
-1000
-500
0
500
0 50 100 150 200 250 30
xpp [m/s2]
-2000
-1500
-1000
-500
0
500
0 50 100 150 200
xpp
Fig.27. The dynamic diagram at the cosine fourfoldprofile at the cam with translated follower with roll;
r0=13[mm]; h=12[mm]; u=/8[rad]; rb=2[mm];
e=0[mm]; n=5000[rpm]; x0=9[cm]; k=1500[kN/m]
For now is necessary to stop here.If we increase h, or decrease the angle u, then
is tapering cam profile very much. We must stop
now at a yield value, =60%.
Nomenclature
M the mass of the mechanism, reduced
at the valveK the elastically constant of the
systemk the elastically constant of the valve
spring
dt
dMc 2
1
the coefficient of the systemsamortization
F0 the elastically force whichcompressing the valve spring
rF the resistant force
mF the motor forcex the effective displacement of the
valvex0 the valve (tappet) spring preloadx the reduced valve (tappet) speedx the reduced valve (tappet)
acceleration
ys the theoretical displacement of thetappet reduced at the valve, imposedby the cams profile
ys the velocity of the theoretical
displacement of the tappet reducedat the valve, imposed by the camsprofile
mT=m2 the mass of the tappet (of the valvelifter)
m3 the mass of the valve push rod
m5 the valve massJ1=Jc the inertia mechanical moment of
the cam
J4 the inertia mechanical moment ofthe valve rocker
2y the tappet velocity, or the secondmovement-low, imposed by thecams profile
x the real (dynamic) valve velocity
x the real (dynamic) valveacceleration
i=i25 the ratio of transmission tappet-valve, given from the valve rocker
y the tappet velocity reduced at the
valveD the dynamic transmission function(the dynamic transmissioncoefficient)
m the nominal (average) angularvelocity of cam
=1= the angular (real) rotation speed ofthe cam (or camshaft)
4 the angular rotation speed of thevalve rocker
The pressure angle
The additional pressure angle
rb roll radiusr0 basic radius
e horizontally misalignments0 vertical misalignment
BA rr , position vectors
J* the reduced mechanical moment ofinertia
J* the first derivative of the reducedmechanical moment of inertia
J*m the average reduced moment of
inertia
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4. Discussion
In this paper one presents an original methodto determine the dynamic parameters at thecamshaft (the distribution mechanisms). It makesthe synthesis, of the rotary cam and tappet with
translational motion with roll, with a greatprecision.
The authors introduce a new pressure angle,alpha, and a new method to determine the twopressure angles, alpha and delta.
The presented method is the most elegant anddirect method to determine the kinematics anddynamic parameters.
The dynamic synthesis can generate a camprofile which will work without vibrations.
Processes robotization increasingly determineand influence the emergence of new industries,
applications in specific environmental conditions,approach new types of technological operations,handling of objects in outer space, leadingteleoperator in disciplines such as medicine,robots that covers a whole larger service benefitsour society, modern and computerized. In thiscontext, this paper seeks to contribute to thescientific and technical applications in dynamicanalysis and synthesis of cam mechanisms.
In 1971 K. Hain proposes an optimization
method to cam mechanism to achieve the
optimum output transmission angle (maximum)and minimum acceleration [11].In 1979 F. Giordana investigates the influence
of measurement errors in kinematic analysis of
cam [10].In 1985 P. Antonescu presents an analytical
method for the synthesis mechanism flat tappetcam and tappet rocker mechanism [2].
In 1987 F.I. Petrescu presents a new dynamic
model with general applications [3].In 1988 J. Angelas and C. Lopez-Cajun
presents optimal synthesis mechanism oscillating
flat tappet cam and [1].In 1991 B.S. Bagepalli presents a generalized
model of dynamic cam-follower pairs [4].In 1999 R.L. Norton studying the effect of
valve-cam ramps on the valve-train dynamics[12].
Z. Chang presents in 2001 [5] and 2011 [6] astudy on dynamics of roller gear cam system,considering clearances.
In 2002 D. Taraza synthesized analyzes theinfluence of the cam profile, the variation of theangular velocity distribution tree, and the
parameters of power load consumption andemissions of internal combustion engine [16].
In 2005 [13] and 2008 [14], F.I. Petrescu and
R.V. Petrescu present a synthesis method of rotarycam profile, and translational or rotary tappet, flat
or with roll, to obtain high yields output.In 2009 K. Dan makes some research on
dynamic behavior simulation technology for cam-
drive mechanism in single-cylinder engines [7].In 2009 M. Satyanarayana makes a dynamic
experiment in cam-follower mechanism [15].In 2011 Z. Ge makes the design and dynamic
analysis of the cam mechanisms [8-9].
5. Conclusions
The distribution mechanisms work with smallefficiency for about 150 years; this fact affects thetotal yield of the internal heat engines. Much ofthe mechanical energy of an engine is lost throughthe mechanism of distribution. Multi-years theyield of the distribution mechanisms was only 4-8%. In the past 20 years it has managed a lift up tothe value of 14-18%; car pollution has decreasedand people have better breathing again.Meanwhile the number of vehicles has tripled andthe pollution increased again.
Now, its the time when we must try again togrow the yield of the distribution mechanisms.
The paper presents an original method to
increase the efficiency of a mechanism with camand follower, used at the distribution mechanisms.This paper treats only one module: the
mechanism with rotary cam and translated followerwith roll (the modern module B).
At the classical module C we can increase againthe yield to about 30%. The growth is difficult.Dimensional parameters of the cam must be
optimized; optimization and synthesis of the camprofile are made dynamic, and it must set theelastic (dynamic) parameters of the valve (tappet)spring: k and x0.
The law used is not as important as the moduleused, sizes and settings used. We take the classicallaw cosine; dimensioning the radius cam, liftheight, and angle of lift.
To grow the cam yield again we must leave theclassic module C and take the modern module B.In this way the efficiency can be as high as 60%.
Yields went increased from 4% to 60%, andwe can consider for the moment that we have gainimportance, since we work with the cam andtappet mechanisms.
If we more increase h, or decrease the angle
u, then is tapering cam profile very much. Wemust stop now at a yield value, =60%.
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It can synthesize high-speed cam, or high-
performance camshafts.
6. References
[1]
Angelas J., Lopez-Cajun C., Optimalsynthesis of cam mechanisms with oscillatingflat-face followers. Mechanism and MachineTheory 23,(1988), Nr. 1., p. 1-6., 1988.
[2] Antonescu, P., Petrescu, F., Antonescu, O.,Contributions to the Synthesis of The RotaryDisc-Cam Profile, In VIII-th InternationalConference on the Theory of Machines andMechanisms, Liberec, Czech Republic, p. 51-56, 2000.
[3] Antonescu, P., Oprean, M., Petrescu, F.I.,Analiza dinamic a mecanismelor dedistribuie cu came. n al VII-lea SimpozionNaional de Roboi Industriali, MERO'87,Bucureti, 1987, Vol. III, p. 126-133.
[4] Bagepalli, B.S., a.o., Generalized Modelingof Dynamic Cam-follower Pairs inMechanisms, Journal of Mechanical Design,June 1991, Vol. 113, Issue 2, p. 102-109.
[5] Chang, Z., a.o., A study on dynamics ofroller gear cam system consideringclearances, Mechanism and Machine Theory,
January 2001, Vol. 36, N. 1, p. 143-152.
[6]
Chang, Z., a.o., Effects of clearance ondynamics of parallel indexing cammechanism, ICIRA11 Proceedings of the 4thinternational conference on Intelligent
Robotics and Applications Volume, Part I,2011, p. 270-280.
[7] Dan, K., a.o., Research on Dynamic BehaviorSimulation Technology for Cam-DriveMechanism in Single-cylinder Engines, SAE
Technical Paper, 2009, paper number 2009-32-0089.
[8] Ge, Z., a.o., Mechanism Design amd
Dynamic Analysis of Hybrid Cam-linkageMechanical Press, Key EngineeringMaterials Journal, Vol. 474-476 (2011), p.803-806.
[9] Ge, Z., a.o., CAD/CAM/CAE for the Parallel
Indexing Cam Mechanisms, AppliedMechanics and Materials Journal, Vol. 44-47
(2011), p. 475-479.[10] Giordana F., s.a., On the influence of
measurement errors in the Kinematic
analysis of cam. Mechanism and MachineTheory 14 (1979), nr. 5., p. 327-340, 1979.
[11] Hain K., Optimization of a cam mechanismto give goode transmissibility maximaloutput angle of swing and minimalacceleration. Journal of Mechanisms 6(1971), Nr. 4., p.419-434.
[12]Norton, R.L., a.o., Effect of Valve-CamRamps on Valve Train Dynamics, SAE,International Congress & Exposition, 1999,Paper Number 1999-01-0801.
[13] Petrescu, F.I., Petrescu, R.V. Contributions
at the dynamics of cams. In the NinthIFToMM International Symposium onTheory of Machines and Mechanisms,SYROM 2005, Bucharest, Romania, 2005,Vol. I, p. 123-128.
[14] Petrescu F.I., .a., Cams DynamicEfficiency Determination. In New Trends
in Mechanisms, Ed. Academica -Greifswald, 2008, I.S.B.N. 978-3-940237-10-1, p. 49-56.
[15] Satyanarayana, M., a.o., Dynamic Responseof Cam-Follower Mechanism, SAE Technic
Paper, 2009, paper number 2009-01-1416.[16] Taraza, D., "Accuracy Limits of IMEP
Determination from Crankshaft SpeedMeasurements," SAE Transactions, Journalof Engines 111, p. 689-697, 2002.
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AUTHORSINFORMATION
1Dr. Eng. Florian Ion T. Petrescu, Senior Lecturerat UPB (Bucharest Polytechnic University), TMR(Theory of Mechanisms and Robots) department.2Dr. Eng. Relly Victoria V. Petrescu, SeniorLecturer at UPB (Bucharest PolytechnicUniversity), TTL (Transport, Traffic andLogistics) department.
1. Ph.D. Eng. Florian Ion T.PETRESCUSenior Lecturer at UPB (BucharestPolytechnic University), Theory of Mechanismsand Robots department,
Date of birth: March.28.1958; Higher education:Polytechnic University of Bucharest, Faculty ofTransport, Road Vehicles Department, graduated
in 1982, with overall average 9.63;
Doctoral Thesis: "Theoretical and AppliedContributions About the Dynamic of PlanarMechanisms with Superior Joints".
Expert in: Industrial Design, Mechanical Design,Engines Design, Mechanical Transmissions,Dynamics, Vibrations, Mechanisms, Machines,Robots.
Association:
Member ARoTMM, IFToMM, SIAR, FISITA,SRR, AGIR. Member of Board of SRRB(Romanian Society of Robotics).
2. Ph.D. Eng. Relly Victoria V. PETRESCUSenior Lecturer at UPB (Bucharest PolytechnicUniversity), Transport, Traffic and Logisticsdepartment,
Citizenship: Romanian;
Date of birth: March.13.1958;Higher education: Polytechnic University ofBucharest, Faculty of Transport, Road Vehicles
Department, graduated in 1982, with overallaverage 9.50;
Doctoral Thesis: "Contributions to analysis andsynthesis of mechanisms with bars and sprocket".
Expert in Industrial Design, EngineeringMechanical Design, Engines Design, Mechanical
Transmissions, Projective and descriptivegeometry, Technical drawing, CAD, Automotiveengineering, Vehicles, Transportations.
Association:Member ARoTMM, IFToMM, SIAR, FISITA,
SRR, SORGING, AGIR.
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101 82 -65(2014)F lor ian I on T. Petrescu
Florian Ion T. Petrescu* Relly Victoria V. Petrescu** / / / *
/ / / **
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mailto:[email protected]*%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]*%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]*%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]*%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]**%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]**%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]**%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]**%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]**%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]**%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]*%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AFmailto:[email protected]*%D8%A7%D9%84%D8%A8%D8%B1%D9%8A%D8%AF