Star Spring Washers
as ball bearing compensating discs for taking up free movement in bearings
Features
• RINGSPANN­Star­Spring­Washers­are­
particularly­light­spring­elements­with­
linear­or­not-linear­spring­characteristic.
They­are­suitable­for­application­as­pressure
elements­in­precision­machines­and­as­
pressure­springs­for­taking­up­free­
movement,­and­for­reducing­noise­in­
ball­bearings.
• The­very­large­axial­movement­of­the­
spring­guarantees­that­considerable­axial
variations­and­length­tolerances­can­be­
accommodated­without­much­deviation
from­the­nominal­value­of­the­axial­force­
of­the­Star­Spring­Washer.
88-1
• Because­of­the­large­axial­variations­of­
the­spring­it­is­often­possible­to­achieve­
the­desired­effect­with­a­single­Star­Spring
Washer.
• Their­spring­load­corresponds­with­the­
optimum­values­of­the­relevant­bearing
sizes.
Service Life
Ball­bearings­give­longer­service­if­the­inner­and
outer­rings­are­pre-loaded­axially­(figure­88-2).
This­fact­has­been­known­for­a­long­time.­This
axial­ preloading­ by­ RINGSPANN­ Star­ Spring
Washers­eliminates­radial­play­in­the­ball­bearings.­This­effects­a­better­distribution­of­the­radial­load­to­be­transmitted­onto­the­bearing
rings­and­therefore­increases­the­length­of­service­life­of­the­bearing.
Silent Running
Inner and outer rings are pre-loaded axially
88-2
Conditions for most favourable effect
Protection of Bearings subject to
The­ effect­ of­ axial­ pre-loading­ depends­ on­ vibration when non-rotating
certain­conditions:
• The­axial­pressure­must­be­applied­to­the
whole­outer­race.
• Axial­variations­and­length­tolerances­
within­the­components­of­the­machine
should­have­only­the­very­slightest­effect­
on­the­applied­spring­force.
• The­axial­pre-loading­must­be­done­with­
a­load­suitably­adapted­to­the­size­of­the
bearing.
The­ spring­ axial­ location­ also­ eliminates­
damage­as­a­result­of­vibration­in­non-rotating
bearings.­This­type­of­da­mage­is­well­known­in
electric­motors­for­auxiliary­drives­in­ships­and
vehicles.­If­the­auxiliary­drives­is­stationary,­the
rotor­ can­ vibrate­ in­ the­ bearing,­ due­ to­ the­
vibration­ of­ the­ ship­ or­ vehicle.­ In­ these­
conditions­ the­ balls­ beat­ in­ the­ races­ of­ the­
bearing­ rings­ and­ cause­ wear.­ This­ is­ why­
leading­manufacturers­use­only­ball­bearings,
the­ radial­ play­ of­ which­ is­ removed­ by­ Star
Spring­Washers,­so­preventing­any­vibration­of
the­rotor.­The­reason­for­damage­is­then­completely­eliminated.
88
High­speed­machines,­particularly­small­electric
motors,­create­special­problems­for­the­design­er­regarding­silent­running.­Extensive­trials­in
this­field­have­shown,­that­in­the­main,­noise­
originates­in­the­ball­bearings,­and­that­the­application­of­the­exact­amount­of­axial­pressure
suitable­for­each­job­reducing­noise­effectively.
Star Spring Washers
as ball bearing compensating discs for taking up free movement in bearings
Bearing of an internal grinding
spindle
Spindle­ ball­ bearings­ are­ used­ as­ bearing­
support­for­grinding­spindles.­Bearings­of­this
kind­exhibit­maximum­tracking­accuracy­at­high
rotation­speeds.­
The­specific­properties­of­these­bearings­can­
be­fully­exploited­only­if­the­bearings­are­preclamped­with­a­precisely­defined­force.
RINGSPANN­Star­Springs­Washers­enable­you­
to­realise­the­required­pre-clamping­ force­of­
the­spindle­bearings­with­a­high­degree­of­precision.­
Bearing of an internal grinding spindle
89-1
Pressure spring for ball bearing
Silent­running­is­a­particular­requirement­for
electric­motors.­For­this­purpose­a­RINGSPANN
Star­Spring­Washer­acts­to­pre-load­the­outer
race­of­the­bearing­as­illustrated.
Pressure spring for ball bearing
89-2
Accommodating length tolerances
As­shown­in­this­example­the­RINGSPANN­Star
Spring­Washer­fitted­between­output­shaft­and
NILOS­sealing­ring­makes­it­possible­to­accom­modate­wide­axial­tolerances.
Accommodating length tolerances
89
89-3
Star Spring Washers
as ball bearing compensating discs for taking up free movement in bearings
H
h
(w)
Spring
under
tension
ød
øD
With­washers­stacked­in­
parallel,­the­pressure­
forces­are­added.
Washers­with­dish­angles­
opposite,­the­spring­travels
are­added.
Spring
released
S
90-1
Dimension
For­ball­bearing
Height
released
D
mm
634
635
635
E­3
E­4­
E­5
626
626
E­6
E­7
E­8
627
629
629
16100
16101
16002
16003
608
609
E­10­
E­14
E­15­
6002­
6003
E­16
E­19
E­19
L­17a
Bo­15­
E­20
M­20
16006
16007
16008
16009
6000
6000
6001
E­9
E­13
E­11
E­12
16004
16005
16005
L­30
624
625
607
607
EA­17­
L­20­
L­25­
6006
6007­
6008
6200
6201
6201
6202
6300
6301
6203
6203
6004
Bo­17
6005
6005
6205
6302
6204
6206
6305
6403
6207
6306
6404
6303
6304
6009
12,7
15,7
18,7
18,7
20,7
21,7
23,7
25,7
25,7
27,7
29,7
31,7
31,7
34,7
36,7
37,7
39,7
39,7
41,7
43,5
46,5
46,5
51,5
54,5
61
67
71
74
d
mm
5,3
7,5
7,5
9,2
10,5
11
11
11
13,5
15
15
15
18
20
20
20
20
23
27
27
27
30
35
35
40
45
45
50
s
mm
0,3
0,3
0,3
0,3
0,3
0,5
0,5
0,5
0,5
0,65
0,65
0,65
0,65
0,9
0,9
0,9
0,9
0,9
0,9
0,9
0,9
0,9
0,9
1,15
1,15
1,15
1,15
1,15
H
mm
1,1
1,1
1,4
1,2
1,3
1,6
1,8
2,0
1,7
1,9
2,1
2,3
2,0
2,4
2,6
2,7
2,9
2,6
2,4
2,6
2,9
2,6
2,6
3,1
3,3
3,4
3,8
3,6
under
pressure
h
mm
0,7
0,7
0,7
0,7
0,7
0,9
1,0
1,0
1,0
1,1
1,1
1,1
1,1
1,4
1,4
1,4
1,4
1,4
1,4
1,4
1,4
1,4
1,4
1,7
1,7
1,7
1,7
1,7
Tolerance
for
h
Spring
travel
Pressure
Spring
const.
Article­
number
mm
(w)
mm
F
N
c
N/mm
1051-
±­0,15
±­0,15
±­0,15
±­0,15
±­0,15
±­0,15
±­0,2
±­0,2
±­0,2
±­0,2
±­0,21
±­0,2
±­0,21
±­0,2
±­0,21
±­0,2
±­0,2
±­0,2
±­0,2
±­0,2
±­0,2
±­0,2
±­0,2
±­0,25
±­0,25
±­0,25
±­0,25
±­0,25
0,4
0,4
0,7
0,5
0,6
0,7
0,8
1,0
0,7
0,8
1,0
1,2
0,9
1,0
1,2
1,3
1,5
1,2
1,0
1,2
1,5
1,2
1,2
1,4
1,6
1,7
2,1
1,9
14
9
10
11
7
34
33
31
30
52
38
46
36
89
92
84
81
103
76
68
74
72
61
98
110
90
110
130
35
23
14
22
12
49
41
31
43
65
38
38
40
89
77
65
54
86
76
57
49
60
51
70
69
53
52
68
012001
015001
018001
018002
020001
021001
023001
025001
025002
027001
029001
031001
031002
034001
036001
037001
039001
039002
041001
043001
046001
046002
051001
054001
061001
067001
071001
074001
Mounting
Generally­it­will­be­found­most­suitable­for­the
Star­Spring­Washer­to­work­on­the­outer­ring­of
the­ball­bearing.­The­Star­Spring­Washer­outside
diameters­given­in­the­following­table­­corre­spond­therefore­with­the­ball­bearing­outside
diameters.­The­RINGSPANN­design­with­slots
and­dished­shape­guarantees­even­axial­pressure­on­the­whole­outer­race.­If­an­axial­pressure
is­applied­to­the­shaft­in­one­direction­only,­the
Star­Spring­Washer­must­be­mounted­in­such­a
way­that­there­is­no­axial­pressure­on­it­(figure
89-2).­If­the­axial­pressures­vary­or­are­in­both­di-
90
rections,­a­Star­Spring­Washer­has­to­be­mounted­both­sides­of­the­ball­bearings.­In­this­case
and­in­any­doubtful­cases­we­will­be­pleased­to
submit­an­installation­proposal.
Star Spring Washers
as ball bearing compensating discs for taking up free movement in bearings
H
h
(w)
Spring
under
tension
ød
øD
With­washers­stacked­in­
parallel,­the­pressure­
forces­are­added.
Washers­with­dish­angles­
opposite,­the­spring­travels
are­added.
Spring
released
S
91-1
Height
released
D
mm
16010
6010­
16011
16012
16013
16014
16015
6011­
6012
6013­
6014­
6015
16016
16017
16018
16019
16020
16021
16022
16024
6016­
6017­
6018­
6019
6020­
6021­
6022­
6024­
16026
16028
6026­
6028
16030
6030
6208
6209
6210
6307
6405
6308
6406
6211
6212
6309
6310
6407
6408
6213
6214
6215
6216
6311
6409
6312
6313
6410
6411
6217
6218
6219
6220
6221
6222
6314
6315
6316
6317
6318
6319
6412
6413
6224
6320
6321
6414
6415
6416
6417
6418
6226
16032
6032
6322
6228
16034
6034
6324
79
84
89
94
99
109
114
119
124
129
139
144
149
158
168
178
188
198
208
213
223
228
238
248
258
d
mm
58
63
63
68
73
78
83
88
93
98
98
103
108
118
123
133
138
143
163
168
183
188
198
211
223
s
mm
1,15
1,15
1,15
1,15
1,15
1,15
1,15
1,15
1,15
1,15
1,25
1,25
1,25
1,5
1,5
1,5
2,1
2
2
2
2
2
2
2
2
H
mm
3,3
3,3
3,8
3,8
3,8
4,2
4,2
4,2
4,2
4,2
5,3
5,3
5,3
5,5
6
6
7
7,5
6,2
6,4
6,1
6,2
6,4
6,2
6,2
under
pressure
h
mm
1,7
1,7
1,7
1,9
1,9
2,0
2,0
2,0
2,0
2,0
2,3
2,3
2,3
2,5
2,7
2,7
3,3
3,3
3,0
3,1
3,0
3,0
3,1
3,0
3,0
Explanation concerning the table
Apart­from­the­listed­ball­bearing­series­the­Star
Spring­Washers­can­also­be­used­for­series­32,
33,­42,­72­and­73.­Pressure­F­is­attained­at­height
h.­The­ spring­ constant­ c,­ i.e.­ the­ pressure­ increase­per­mm­spring­travel­can­only­be­given
up­to­size­74­x­50­x­1,15.­
Tolerance
for
h
Spring
travel
Pressure
Spring
const.
Article­
number
mm
(w)
mm
F
N
c
N/mm
1052-
±­0,25
±­0,25
±­0,25
±­0,4
±­0,4
±­0,4
±­0,4
±­0,4
±­0,4
±­0,4
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
±­0,5
1,6
1,6
2,1
1,9
1,9
2,2
2,2
2,2
2,2
2,2
3,0
3,0
3,0
3,0
3,3
3,3
3,7
4,2
3,2
3,3
3,1
3,2
3,3
3,2
3,2
290
320
290
260
280
180
200
270
250
250
330
330
370
410
470
600
520
660
1160
1120
1200
1160
1120
1160
1180
Diminishing­spring­characteristic
Dimension
For­ball­bearing
079001
084001
089001
094001
099001
109001
114001
119001
124001
129001
139001
144001
149001
158001
168001
178001
188001
198001
208001­
213001
223001
228001
238001
248001
258001
Example for ordering
With­larger­Star­Spring­Washers­the­spring­characteristic­is­not­linear­but­diminishing.­With­tolerances­of­the­installation­height­h­the­pressure
F­therefore­changes­even­less­than­with­smaller
washers.
91
Star­ Spring­Washer­ for­ ball­ bearings­ of­ series
16011:
• Article­number 1052-089001