MK3
Miniature Bellows Coupling with expanding shaft

0.5 - 10 Nm

MK3 MINIATURE BELLOWS COUPLING WITH EXPANDING SHAFT

Specifications MK3

MK3 series 5 10 15 20 45 100
Rated torque (Nm) TKN 0.5 1.0 1.5 2.0 4.5 10
Overall length (mm) A
202326
222528
2430
273336
3644
4151
Outside diameter (mm) B 15 15 19 25 32 40
Fit length (mm) C1 9 9 11 13 16 16
Shaft length (mm) C2 10 10 12 12 15 20
Inside diameter possible
from Ø to Ø H7 (mm)
D1
3-7 3-7 4-8 4-12.7 5-16 6-24
Inside diameter possible
from Ø to Ø H7 (inch)
D1
0,125"-
0,250"
0,125"-
0,250"
0,187"-
0,313"
0,187"-
0,500"
0,250"-
0,625"
0,250"-
0,875"
Standard shaft possible
from Ø to Ø f7 (mm)
D2
8-10 8-10 10-14 10-16 14-20 16-24
Fastening screw ISO 4762 E M2 M2 M2.5 M3 M4 M4
Tighting torque of the assembly screw (Nm) E 0.43 0.43 0.85 2.3 4 4.5
Distance between centerlines (mm) F 4.5 4.5 6 8 10 15
Distance (mm) G 3 3 3.5 4 5 5
Fastening screw ISO 4762 I M3 M3 M4 M4 M5 M6
Tightening torque of the
fastening screws (Nm)
I
1.5 1.5 3 4 6.5 11
Moment of inertia (gcm2) J
2.62.83.0
3.03.43.6
8.59.5
252729
100108
160205
Torsional stiffness (Nm/rad) CT
280210170
510380320
750700
120013001200
70005000
90508800
axial (mm) max.
0.40.50.6
0.40.50.6
0.50.7
0.50.60.7
0.71
11.2
lateral (mm) max.
0.150.20.25
0.150.20.25
0.150.2
0.150.20.25
0.20.25
0.20.3
angular (degrees) max.
11.52
11.52
1.5
1.51.52
1.52
1.52
CAD Portal 5 10 15 20 45 100
2D/3D Data 

Properties

  • Design:
    • on one side with a single radial clamping screw ISO 4762
    • on one side an expanding shaft with tapered clamping element.
  • Temperature range: -30° C to +110° C (-22° F to +230° F)
  • Tolerance: On the hub/shaft connection 0.01 to 0.05 mm.
  • Service life: These couplings have an infinite life, and are maintenance-free if the technical ratings are not exceeded.
  • Material:
    • bellows are made of highly flexible high-grade stainless steel
    • clamping hub aluminium
    • expanding hub and cone (steel)
  • Speeds: Up to 10,000 rpm, in excess of 10,000 rpm available with balanced version.
  • Non-standard application: Custom designs with varied tolerances, keyways, non-standard material and bellows are available upon request.
  • Properties of Miniature Coupling model MK3:
    • backlash-free and torsionally rigid
    • compensates for 3-axis of misalignment
    • easy mounting
    • compact design, conserves space while saving cost
    • low moment of inertia

Overview