The total angular deflection,
end of the spring (
e
t
, (in radians) is given in terms of the expression above and the rotation due to the
) as
2
t
64 M D
e
d4E
Nb
l1 l2
3D
The total number of active turns is defined as N a
Ne
Nb
N e , where N e is the nu
2 A deep-mine hoist utilizes a single line of 2-inch 6 19 extra improved plow steel (EIPS) wire rope
wrapped on a cast carbon-steel drum that has a diameter of 6 feet. The rope is used to vertically lift loads of
ore weighing about 4 tons from a shaft tha
E xa mp le 2
A short-shoe block brake consists of a 3.0-in-diameter drum
rotating clockwise at 500 rpm and an actuation arm configured
as show. The shoe is molded fiberglass, the drum is aluminumbronze and the entire assembly is water -sprayed. The coeffi
AntiFriction (Rolling Element) Bearings
Chapter 11
Anatomy of a Bearing
How do you assembly a bearing?
Types of Bearings
Radial Ball Bearings
Radial ball bearings consist of an inner and
outer ring with a cage containing a
complement of precision balls.
MISCELLANEOUS SPRINGS
Miscellaneous Springs
Beleville Springs
The force required to flatten a
Belleville spring is
F flat
4 E ht 3
2
2
1 K1D0
where - Poisson's ratio
E - Elastic modulus
D0 - Outside washer (spring) diameter
Di - Inside washer (spring) d
The torque is determined from
T
pmax wc r 2
cos
sin max
1
The horsepower is hp
cos
0.20(3)(8)2 (69.2) 0.9939 ( 0.1966)
2
Tn
63, 025
(3163.5)(200)
63, 025
3163.5 in-lb
T
3163.5 in-lb
hp 10.04 hp
10.04 hp
(B) Modeling the normal and friction forces as if th
Brake Mount
Gearbox Pad
Brake Caliper (Wilwood 4- piston)
Rotor
Rigid mount
Brake Rotor (4340 or carbon steel)
Piston
Pad
Blanchard ground finish
One- or two- piece design
Top Hat (6061 AL)
Vented for cooling
Pilot Diameter
Gearbox output
Grease- packed B
So l u t io n
(a)
r
d
2
2.0000
1.0000 inch
2
n
3000 rpm
50
rev
sec
From Table 10.2, for an automotive crankshaft application using a copper -lead alloy bearing sleeve and a steel
journal, for a 2-inch diameter bearing
c
c
r
0.0014 inch
0.0014
1.0000
0.001
FLYWHEELS
Flywheels
Mo t o r
A flywheel is a rotating mass used to stabilize (or
smooth out) variations in the speed of the shaft
caused by torque fluctuations. The primary task of a
flywheel is to control, within an acceptable band, the
angular velocity
The spring rate can be defined as k
terms of the moment, this becomes
U AB
P
A
where
M/ P
A
1
M
EI 0
R 1 cos
U AB
P
1
EI
0
P/
A,
where is
A
determined from
A
U AB / P . Expressed in
M / P Rd
. Using this we write
RP 1 cos
PR3 3
EI 2
2 sin
R 1 cos
Rd
/3
1
Next
hplim
ns pN s
n
4.413 2.073 p 0.0274 N L
ln l
1.59 log p 1.873
110.84
1000
2170(0.5)(25)
1750
4.413 2.073(0.5) 0.0274(31)
ln
1.59 log(0.5) 1.873
110.84
1000
g
hplim
g
284 horsepower
This is acceptable. Summarizing
Use 1-strand no. 40 precision roller