Wittenstein Components & Systems. Catalog 2012/2013 - page 44

ELC — Elastomer coupling

ELC model

Series

2

5

10

20

60

150

300

450

800

Type (elastomer ring)

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

Rated torque

T

KN

 Nm

2

2.4 0.5

9

12

2

12.5 16

4

17

21

6

60

75

20 160 200 42 325 405 84 530 660 95 950 1,100 240

Max. torque**

T

Kmax 

 Nm

4

4.8

1

18

24

4

25

32

6

34

42

12 120 150 35 320 400 85 650 810 170 1,0601,350 190 1,900 2,150 400

Installation length

A mm

20

26

32

50

58

62

86

94

123

Outer diameter

B mm

16

25

32

42

56

66.5

82

102

136.5

Outer diameter of screw head B

S

 mm

17

25

32

44.5

57

68

85

105

139

Fit length

C mm

6

8

10.3

17

20

21

31

34

46

Possible inner diameter 
from Ø to Ø H7 

D

1/2

 

mm

3 to 8

4 to 12.7

4 to 16

8 to 25

12 to 32

19 to 36

20 to 45

28 to 60

35 to 80

Max. inner diameter 
(elastomer ring)

D

E

 mm

6.2

10.2

14.2

19.2

26.2

29.2

36.2

46.2

60.5

Fastening screw 
(ISO 4762/12.9)

E 

M2

M3

M4

M5

M6

M8

M10

M12

M16

Tightening torque 
of fastening screw

 Nm

0.6

2

4

8

15

35

70

120

290

Distance between centers F  

mm

5.5

8

10.5

15.5

21

24

29

38

50.5

Distance

G 

 mm

3

4

5

8.5

10

11

15

17.5

23

Hub length

H 

 mm

12

16.7

20.7

31

36

39

52

57

74

Moment of inertia per hub J1/J2 10

-3

 kgm

2

0.0003

0.002

0.003

0.01

0.04

0.08

0.3

0.66

8

Coupling weight

 kg

0.008

0.02

0.05

0.12

0.3

0.5

0.9

1.5

8.5

Speed*

 rpm

28,000

22,000

20,000

19,000

14,000

11,500

9,500

8,000

4,000

Series

dia.

 3

dia.

 4

dia.

 5

dia.

 8

dia.

 16

dia.

 19

dia.

 25

dia.

 30

dia.

 32

dia.

 35

dia.

 45

dia.

 50

dia.

 55

dia.

 60

dia.

 65

dia.

 70

dia.

 75

dia.

 80

2

0.2

0.8

1.5

2.5

5

1.5

2

8

10

4

12

32

20

20

35

45

60

60

50

80

100

110

120

150

120

160

180

200

220

300

200

230

300

350

380

420

450

420

480

510

600

660

750

850

800

700

750

800

835

865

900

925

950

1,000

Higher torques possible by means of additional keys.

Model series EL

Series

2

5

10

20

60

150

300

450

800

Elastomer ring 
type

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

Static torsional 
rigidity

C

T    

Nm/arcmin

0.015 0.033 0.0049 0.044 0.10 0.015 0.076 0.17 0.026 0.33 0.73 0.15 0.96

2.8

0.41

1.4

3.1

0.33

3.6

5.2

0.37

4.4

7.9

1.2

12

19

3.0

Dynamic tor-
sional rigidity

C

Tdy

Nm/arcmin

0.029 0.067 0.010 0.087 0.20 0.031 0.16 0.48 0.065 0.74

1.3

0.25

2.3

3.5

0.39

3.9

8.5

1.0

6.9

12

1.8

16

24

3.4

24

52

8.3

Lateral

Max.  
values 

mm

0.08 0.06 0.1 0.08 0.06 0.1

0.1 0.08 0.12 0.1 0.08 0.15 0.12 0.1 0.15 0.15 0.12 0.2 0.18 0.14 0.25 0.2 0.18 0.25 0.25 0.2

0.3

Angular

Max. values 
 

Degrees

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

Axial

Max.  
values 

mm

±1

±1

±1

±2

±2

±2

±2

±2

±2

Static torsional rigidity at 50% T

KN 

    

Dynamic torsional rigidity at T

KN

** Maximum torque transmitted T

Kmax 

by clamping hub dependent upon bore diameter

364

alpha

A

G

H

ØB 

C

C

E ISO 4762

F

ØD

2H7

ØB

S

ØD

1H7

ØD

E

A

G

H

ØB 

C

C

E ISO 4762

F

ØD

2H7

ØB

S

ØD

1H7

ØD

E

a) 

Accessories

Couplings

Features:

 · Short design
 · Easy installation
 · Vibration damping
 · Backlash-free
 · Plug-in

Material:

Coupling hubs: up to series 450 high-strength aluminum,  
from series 800 and up steel
Elastomer ring: precision molded, wear-resistant,  
and thermally-stable polymer

DIN 6885 optional

Elastomer ring, optionally  
type A / B / C

The equalizing element of an EK coupling is the elastomer ring. It trans-
mits the torque without backlash or vibration. The elastomer ring 
defines the features of the entire coupling and/or of the entire drive train.

The backlash-free nature of the coupling is due to pre-tensioning 
of the elastomer ring between the two coupling halves. The alpha 
coupling compensates for lateral, angular and axial misalignment.

Function of elastomer ring

Specification of the elastomer rings

Version

Shore hardness

Color

Material

Relative damping (

ψ

)

Temperature range

Features

A

98 Sh A

Red

TPU

0.4-0.5

-30°C to +100°C

Good damping

B

64 Sh D

Green

TPU

0.3-0.45

-30°C to +120°C

High torsional rigidity

C

80 Sh A

Yellow

TPU

0.3-0.4

-30°C to +100°C

Very good damping

The values for proportional damping were determined at 10 Hz and +20˚C.

Version C

Shore hardness 80 Sh A

Version A

Shore hardness 98 Sh A

Version B

Shore hardness 64 Sh D

Design: 

Two coupling hubs are concentrically machined with concave driv-
ing jaws

*Speeds:

Over 4,000 rpm, a finely balanced version is available

Tolerance:

On the hub/shaft connection, 0.01 to 0.05 mm

a)

 included in scope of delivery

365

EL6 – Elastomer coupling

EL6 model

Series

10

20

60

150

300

450

800

Type (elastomer ring)

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

Rated torque

T

KN

 Nm 12.6 16

4

17

21

6

60

75

20

160 200

42

325 405

84

530 660

95

950 1,100 240

Max. torque

T

Kmax 

 Nm

25

32

6

34

42

12

120 150

35

320 400

85

650 810 170 1,0601,350 190 1,9002,150 400

Installation length

A mm

42

56

64

76

96

110

138

Outer diameter

B mm

32

43

56

66

82

102

136.5

Fit length

C mm

15

20

23

28

36

42

53

Possible inner diameter 
from Ø to Ø H7 

D

1/2

 

mm

6 to 16

8 to 24

12 to 32

19 to 35

20 to 45

28 to 55

32 to 80

Max. inner diameter 
(elastomer ring)

D

E

 mm

14.2

19.2

26.2

29.2

36.2

46.2

60.5

Fastening screw 
(ISO 4762/12.9)

E 

3x M3

6x M4

4x M5

8x M5

8x M6

8x M8

8x M10

Tightening torque 
of fastening screw

 Nm

2

3

6

7

12

35

55

Elastomer ring width

F  

mm

9.5

12

14

15

18

20

25

Moment of inertia per hub J1/J2 10

-3

 kgm

2

0.004

0.015

0.05

0.1

0.3

0.85

9.2

Coupling weight

 kg

0.08

0.12

0.3

0.5

0.9

1.5

9.6

Speed

 rpm

20,000

19,000

14,000

11,500

9,500

8,000

4,000

Model series EL

Series

10

20

60

150

300

450

800

Elastomer ring type

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

Static torsional rigidity

C

T 

 

Nm/arcmin

0.076

0.17

0.026

0.33

0.73

0.15

0.96

2.8

0.41

1.4

3.1

0.33

3.6

5.2

0.37

4.4

7.9

1.2

12

19

3.0

Dynamic torsional rigidity C

Tdyn 

Nm/arcmin

0.16

0.48

0.065

0.74

1.3

0.25

2.3

3.5

0.39

3.9

8.5

1.0

6.9

12

1.8

16

24

3.4

24

52

8.3

Lateral

Max.  
values mm

0.1

0.08

0.12

0.1

0.08

0.15

0.12

0.1

0.15

0.15

0.12

0.2

0.18

0.14

0.25

0.2

0.18

0.25

0.25

0.2

0.3

Angular

Max. values 
 Degrees

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

1

0.8

1.2

Axial

Max.  
values mm

±1

±2

±2

±2

±2

±2

±2

Static torsional rigidity at 50% T

KN 

    

Dynamic torsional rigidity at T

KN

366

alpha

ØD

E

ØD

2

H7

ØD

1

H7

A

C

C

ØB

E ISO 4762

F

ØD

E

ØD

2

H7

ØD

1

H7

A

C

C

ØB

E ISO 4762

F

Accessories

Couplings

Features:

 · High clamping force
 · Very high true-running accuracy
 · Easy installation
 · Vibration damping
 · Backlash free
 · Plug in
 · Axial installation

Alternative elastomer rings
version A / B / C

The equalizing element of an EK coupling is the elastomer ring. It trans-
mits the torque without backlash or vibration. The elastomer ring defines 
the features of the entire coupling and/or of the entire drive train.

The backlash-free nature of the coupling is due to pre-tensioning 
of the elastomer ring between the two coupling halves. The alpha 
coupling compensates for lateral, angular and axial misalignment.

Function of elastomer ring

Specification of the elastomer rings

Version

Shore hardness

Color

Material

Relative damping (

ψ

) Temperature range

Features

A

98 Sh A

Red

TPU

0.4-0.5

-30°C to +100°C

Good damping

B

64 Sh D

Green

TPU

0.3-0.45

-30°C to +120°C

High torsional rigidity

C

80 Sh A

Yellow

TPU

0.3-0.4

-30°C to +100°C

Very good damping

The values for proportional damping were determined at 10 Hz and +20˚C.

Version C

Shore hardness 80 Sh A

Version A

Shore hardness 98 Sh A

Version B

Shore hardness 64 Sh D

Material:

Coupling hubs and conical clamping ring: up to series  
450 high-strength aluminum, from series 800 and up steel
Elastomer ring: precision molded, wear-resistant,  
and thermally-stable polymer

Design: 

Two coupling hubs are concentrically machined with  
concave driving jaws

Tolerance:

On the hub/shaft connection, 0.01 to 0.05 mm

367

Single position  

re-engagement –  

standard version

After the overload has been removed, 
the torque limiter can be re-engaged 
precisely 360 degrees from the original 
disengagement position.
A proven principle that guarantees 
synchronism. Signal in the event 
of an overload. Suitable for use in 
machine tools, packaging machines 
and automation systems.

Order code: W

Load holding version

In the event of an overload, the 
drive and the drive elements are not 
separated or are only allowed limited 
rotation. Guaranteed load safety. 
Automatic engagement of the torque 
limiter after the torque level has 
dropped. Signal in the event of an 
overload. Suitable for use on presses 
or load-lifting equipment.

Order code: G

Torsional backlash

Safe torque limitation

TL – Torque limiters

368

alpha

Accessories

Couplings

Multi-position version

Coupling re-engages automatically at 
the very next ball detent. The coupling 
is immediately ready for operation again 
at several points after an overload. 
Immediate availability of the machine 
or plant as soon as the overload has 
been removed. Signal in the event of an 
overload. Standard engagement after 
60 degrees. Optional engagement after 
30, 45, 60, 90 and 120 degrees.

Order code: D

Full disengagement version

Permanent separation of the drive and 
the drive elements in the event of an 
overload. Spring flips over completely. 
No residual friction. Torque limiter can 
be re-engaged manually (re-engagement 
possible every 60 degrees).

Order code: F

Disc spring position when the coupling 
is disengaged

369

1.5

2

4.5

10

15

30

60

150

200

300

500

800

1500

2500

0.1 – 0.6

0.2 –1.5

1 – 3

2 – 6

5 – 15

5 – 20

10 – 30

20 – 70

30 – 90

100 – 200

80 – 200

400 –650

600 – 800

1500 –2000

1-6

2-14

9-27

18-54

45-133

45-177

89-266

177-620

266-797

885-1770 708-1770

3540-5753

5310-7080

13275-17700

0.4 – 1

0.5 – 2.2

2 – 4.5

4 – 12

12 – 25

10 – 30

25 – 80

45 –150

60 –160

150 –240

200 –350 500 – 800

700 –1200

2000 –2500

4-9

5-20

18-40

36-107

107-222

89-266

222-708

399-1328 531-1416

1328-2124

1770-3098

4425-7080

6195-10620

17700-22125

0.8 – 2

1.5 – 3.5

3 – 7

7 – 18

20 – 40

20 – 60

50 – 115

80 – 225

140 –280

220 –440

320 –650

650 –950

1000 –1800

2300 – 2800

8-18

14-31

27-62

62-160

177-354

177-531

443-1018 708-1992

1239-2478

1947-3894

2832-5753

5753-8408

8850-15930

20355-24780

–

–

–

–

35 – 70

50 – 100

–

–

250 – 400

–

–

–

–

–

310-620

443-885

222-3540

0.3 – 0.8

0.5 – 2

2.5 – 4.5

2 – 5

7 – 15

8 – 20

10 – 30

20 – 60

80 –140

120 –180

50 – 150

200 – 400 1000 –1250 1400 –2200

3-8

5-18

23-40

18-45

62-133

71-177

89-266

177-531

708-1239

1062-1593

443-1328

1770-3540

8850-11063

12390-19470

0.6 – 1.3

–

–

4 – 10

–

16 – 30

20 – 40

40 – 80

130 – 200 160 – 300 100 –300 450 – 850 1250 –1500 1800 – 2700

6-12

36-89

142-266

177-354

354-708

1151-1770

1416-2655

885-2655

3983-7523

11063-13275

15930-23895

–

–

–

8 – 15

–

–

30 – 60

80 – 150

–

–

250 – 500

–

–

–

71-133

266-531

708-1328

2213-4425

23

28

32

39

40

50

54

58

63

70

84

95

109

146

23

28

32

39

40

50

54

58

66

73

88

95

117

152

23

29

35

45

55

65

73

92

99

120

135

152

174

242

24

32

42

51.5

62

70

83

98

117

132

155

177

187

258

7

8

11

11

19

22

27.5

32

32

41

41

49

61

80

4 – 8

4 – 12

5 – 14

6 – 20

8 – 22

12 – 22 12 – 29 15 – 37 20 – 44 25 – 56 25 – 56 30 – 60

35 – 70

50 – 100

14

22

25

34

40

47

55

68

75

82

90

100

125

168

22

28

35

43

47

54

63

78

85

98

110

120

148

202

26

32

40

50

53

63

72

87

98

112

128

140

165

240

4xM2 4xM2.5 6xM2.5 6xM3

6xM4

6xM5

6xM5

6xM6

6xM6

6xM8

6xM8 6xM10

6xM12

6xM16

3

4

4

5

6

8

9

10

10

10

12

15

16

24

2.5

3.5

5

8

3

5

5

5

5

6

9

10

13.5

20

5

6

8

11

8

11

11

12

12

15

21

19

25

34

11

15

17

22

27

35

37

39

44

47

59

67

82

112

11.5

16

18

24

27

37

39

41.5

47

51.5

62

75

91

120

2.5

4

4

5

–

–

–

–

–

–

–

–

–

–

M2.5

M3

M4

M4

M4

M5

M5

M6

M6

M8

M8

M10

M12

M16

1

2

4

4.5

4

6

8

12

14

18

25

40

70

120

9

18

36

40

36

54

71

107

124

160

222

354

620

1062

20

25

32

40

–

–

–

–

–

–

–

–

–

–

13

18

21

30

35

42

49

62

67

75

84

91

112

154

11

14

17

24

27

32

39

50

55

65

72

75

92

128

6.5

8

10

15

–

–

–

–

–

–

–

–

–

–

1

1.3

1.5

1.5

2.5

2.5

2.5

2.5

3

3

4

4

4.5

6

0.01

0.02

0.05

0.07

0.15

0.25

0.50

1.60

2.70

5.20

8.60

20

31.5

210

0.0089

0.0177

0.0443

0.0620

0.1328

0.2213

0.4425

1.4161

2.3897

4.6024

7.6116 17.7014

27.8797

185.86

0.03

0.065

0.12

0.22

0.4

0.7

1.0

1.3

2.0

3.0

4.0

5.5

10

28

0.066

0.143

0.265

0.485

0.882

1.543

2.205

2.866

4.409

6.614

8.818 12.125

22.046

61.729

0.7

0.8

0.8

1.2

1.5

1.5

1.7

1.9

2.2

2.2

2.2

2.2

3.0

3.0

Series

Miniature design series

Adjustment range from – to 

(approx. values)

T

KN

Nm

A

in.lb

Nm

B

in.lb

Nm

C

in.lb

Nm

D

in.lb

Adjustment range from – to 

(approx. values),

  full  disengagement       

T

KN

Nm

A

in.lb

Nm

B 

in.lb

Nm

C

in.lb

Overall length

A 

mm

Overall length,  
full disengagement

A

F

 

mm

Outer diameter of actuation ring

B 

mm

Actuation ring Ø,  
full disengagement

B

F

 

mm

Clamping fit length

C 

mm

Inner diameter from Ø to Ø H7

D 

mm

Centering diameter h7

E 

mm

Hole circle diameter ±0.2

F 

mm

Flange diameter – 0.2

G 

mm

Thread

H

Thread length

I 

mm

Centering length – 0.2

J 

mm

Distance

K 

mm

Distance

L 

mm

Distance, full disengagement

L

F

 

mm

Distance

M

Screws to ISO 4762

N

Tightening torque

N 

Nm

in.lb

Outer diameter of clamping ring

O

1

 

mm

Diameter

O

2

 

mm

Diameter h7

O

3

 

mm

Distance between centers

P 

mm

Distance

R 

mm

Moment of inertia

J  10

3

kgm²

in.lb.s

2

.10

3

Approx. weight

 

kg

lb

Actuation path

 

mm

A

F

, B

F

, L

F

 = Full disengagement version

TL1 – Torque limiter

370

alpha

Accessories

Couplings

  Torque limiter for timing belt and sprocket applications

Torque limiter TL1 

(1.5 – 10) 

With clamping hub

Torque limiter TL1 

(15 – 2500) 

With conical clamping hub

For actuation path, see table

Bore hole for wrench

Keyway optional

For actuation path, see table

Bore hole for wrench

Material:

High-strength, hardened steel.

Design:

Model TL1: 1.5 – 10 Nm (13.3 – 88.5 in.lb) 
with split clamping hub.
Model TL1: 15 – 2500 Nm (132.8 – 22125 in.lb )
with conical clamping hub.

Temperature range:

 -30 °C to +120°C (-22 °F to 248°F)

Temperature peaks:

 

up to +150°C (302°F)

Backlash:

Completely backlash-free as a result of the 
frictional clamp connection and patented preload.

Service life:

These torque limiters are permanent and 
maintenance-free as long as the performance limits are not 
exceeded.

Fit tolerance:

 

Tolerance between shaft and hub 0.01 – 0.05 mm

371