Maintenance Instructions - Ottobock 3R20 Gebrauchsanweisung

5.2 Replacing the Extension Stop (5) (Figs. 5 –7)
Flex the knee joint. Loosen the Cap Screw (4) using a 3 mm hex head wrench. Remove the Plastic
Knee Cap (3). Turn the Adjustment Screw (5) until the Extension Stop drops out. Use a 4 mm
hex head wrench.
When replacing the Extension Stop first turn the Adjustment Screw (5) into the threaded hole
by hand, two to three threads. At the same time, place the guide groove in the Extension Stop
opposite the guide piece on the Upper Joint Section. Hold the Extension Stop with the left hand
while turning the Adjustment Screw using a hexagonal wrench until the guide groove engages
the guide piece.
5.3 Replacing the Stop Bumper (7) (Figs. 8 –10)
Remove the Spring for Extension Assist (12) according to the instructions presented under sec-
tion 4.3. Loosen the Set Screw (16) which holds the upper axis pin of the Posterior Linkage Bar
(6) using a 3 mm hex head wrench.
Push out the Posterior Axis Pin (19) using a blunt object. Rotate the Posterior Linkage Bar distally
and replace the Stop Bumper (7).
Assemble in the reverse order and lubricate the metal surfaces with 633F16 Lubricant. When
inserting the Posterior Axis Pin (19), check to make sure the flat area in the middle of the pin is
opposite the Set Screw (16).
Tighten Set Screw (16) using a torque wrench. Torque: 7 Nm/5.2 ft.lbf./62 lbf.in.
To secure the screws use 636K13 Loctite.
6 Cosmetic foam cover
Use foam cover 3R24, 3S124, 3R57 for joints 3R20/3R36.
Attention!
To eliminate noise in the cosmetic foam cover, use 519L5 Silicone Spray. Do not use
talcum powder! Talcum powder reduces the lubrication of the mechanical parts, which
may lead to a malfunction and thus increase the risk of failure. Using this medical
product after application of talcum powder will render all claims against Otto Bock
HealthCare null and void.
Notice:
To optimise sliding and for eliminating noises, please apply 519L5 Silicone Spray directly
on the friction surfaces of the cosmetic foam covers.

7 Maintenance instructions

Attention!
Do not use any aggressive cleaning agents since they could cause damage to bearings,
seals and plastic parts.
Do not disassemble the knee joint! If you have a problem, please send the joint to Ottobock.
3R20, 3R36 Ottobock | 15