MK4
Miniature Bellows Coupling with radial set screws and press-fit connection

0.5 - 10 Nm

MK4 MINIATURE BELLOWS COUPLING WITH RADIAL SET SCREWS AND PRESS-FIT CONNECTION

Specifications MK4

MK4 series 5 15 20 45 100
Rated torque (Nm) TKN 0.5 1.5 2.0 4.5 10
Overall length (inserted)(mm) A
222528
2631
283337
3947
4656
Outside diameter (mm) B 15 19 25 32 40
Fit length (mm) C1 6.5 7.5 11 13 15
Fit length (mm) C2 9 10 11 14 16
Inside diameter possible
from Ø to Ø H7 (mm)
D1
3-9 3-12 3-16 6-22 6-28
Inside diameter possible
from Ø to Ø H7 (inch)
D1
0,125"-
0,313"
0,125"-
0,437"
0,125"-
0,625"
0,250"-
0,750"
0,250"-
1,000"
Inside diameter possible
from Ø to Ø H7 (mm)
D2
3-6.35 3-9 3-12.7 6-16 6-20
Inside diameter possible
from Ø to Ø H7 (inch)
D2
0,125"-
0,250"
0,125"-
0,313"
0,125"-
0,500"
0,250"-
0,625"
0,250"-
0,750"
Fastening screw ISO 4029 E 1x M3 2x M3 2x M4 2x M5 2x M6
Tightening torque of the
fastening screws (Nm)
E
1.3 1.3 2.5 4 6
Distance (mm) G 2 2 2.5 3.5 4
Approximate pretensioning (mm) H 0.4 0.5 0.5 0.7 1
Axial recovery force at maximum
pretensioning (N)
532
43
343
1510
2530
Moment of inertia (gcm2) Jges
2.02.22.5
5.56.0
212325
8085
200210
Torsional stiffness (Nm/rad) CT
280210170
750700
120013001200
70005000
90508800
axial (mm) max.
0.40.50.6
0.50.7
0.50.60.7
0.71
11.2
lateral (mm) max.
0.150.20.25
0.150.2
0.150.20.25
0.20.25
0.20.3
angular (degrees) max.
11.52
1.5
1.51.52
1.52
1.52
CAD Portal 5 15 20 45 100
2D/3D Data 

Properties

  • Design:
    • both hubs have radial set screws and integral dismounting grooves.
    • 
incorporates a blind mate press-fit connection.
  • Temperature range: -30° to +110°C (-22° F to +230° F)
  • Tolerance: On the hub/shaft connection 0.01 to 0.08 mm.
  • Service life: These couplings have an infinite life, and are maintenance-free if the technical ratings are not exceeded.
  • Material:
    • bellows made of highly flexible high-grade stainless steel
    • 
clamping hubs and tapered female segment on bellows face from aluminium
    • tapered segment on the hub face: glass-fiber reinforced plastic deposited onto an aluminium hub
  • Speeds: Up to 20,000 rpm, in excess of 20,000 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 MK4:
    • Absolutely backlash-free and torsionally rigid
    • compensates for 3-axis of misalignment
    • easy mounting and dismounting
    • electrically insulated
    • no wear
    • low moment of inertia

Overview