Functional ring while walking
No damping for the user. The functional ring is not
compressed.
5.2.5.3 Checking vacuum generation (Harmony only)
Vacuum generation is tested during the dynamic fitting.
Recommended materials: 755Z37 pressure gauge (with T-piece)
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1) Disconnect the hose from the suction connector of the vacuum pump.
2) Connect the hose to the T-piece of the pressure gauge.
3) Connect the pressure gauge with the T-piece to the intake valve on the vacuum pump.
4) Attach the pressure gauge to the prosthesis so that the patient is able to move freely.
5) Have the patient walk 50 steps to activate the vacuum pump.
6) Check whether the vacuum is between 340 hPa and 680 hPa and is maintained for
20 seconds.
If a sufficient vacuum is built up and the vacuum does not decrease within 20 seconds, the
vacuum system is functioning correctly.
If a sufficient vacuum is built up but the vacuum decreases within 20 seconds, determine the
cause (see Page 24).
7) Remove the pressure gauge after completing the test and reinstall the hose on the suction
connection of the vacuum pump.
5.3 Installing the outlet hose (Harmony only)
CAUTION
Improper installation of the outlet hose
Skin irritation, formation of eczema or infections due to contamination with germs
►
Run the outlet hose in such a way that the hose opening is not directed towards parts of the
body or into the cosmetic cover.
A valve with sound suppressor is installed on the outlet of the vacuum pump. The valve has to be
removed in order to install an outlet hose (available separately).
1) Pull the outlet valve with sound suppressor off the vacuum pump.
2) Insert an outlet valve with hose connector into the functional ring.
3) Install the desired outlet hose according to its instructions for use.
5.4 Optional: Installing the foam cover
The foam cover sits between the prosthetic socket and prosthetic foot. It is cut longer in order to
compensate for the movements of the prosthetic foot and prosthetic knee joint. During flexion of
the prosthetic knee joint, the foam cover undergoes posterior compression and anterior elonga
tion. The foam cover should be stretched as little as possible in order to increase its service life.
There is a connecting element (such as a connection plate, connection cap or connection cover)
on the prosthetic foot.
Required materials: degreasing cleaner (e.g. 634A58 isopropyl alcohol), 636N9 contact
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adhesive or 636W17 plastic adhesive
1) INFORMATION: Add as little length as possible so the functional ring can be com
pressed.
Measure the length of the foam cover on the prosthesis and add the length allowance.
TT prostheses: Distal allowance for movement of the prosthetic foot.
TF prostheses: Allowance proximal of the knee rotation point for flexion of the prosthetic knee
joint and distal allowance for movement of the prosthetic foot.
Cause
Functional ring too hard
Possible: Heel wedge
too soft
Correction/solution
Install a softer functional
ring (see Page 26)
Install
a
harder
heel
wedge (see Page 22)
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