The continuous operation of 100 hours required by maxon - typically 500 surgeries - was exceeded many times up to this output performance.
P=M •n This means that the 1-stage gearhead can be operated continuously at the maximum input speed of 60,000 rpm and a torque on the output shaft of 25 mNm. Higher continuous torques (1-stage to max. 50 mNm, 2 and 3 stages up to max. 125 mNm) are permissible under the condition that the speed is reduced proportionally at the same time.
The gearhead can be intermittently overloaded up to a maximum output performance of 40W. The recommended motor speed of <60,000 rpm can, for short-time operation, even be increased to <80,000 rpm. The operating ranges of the gearheads will now be shown in a diagram (fig. 1). The values given for torque and speed always refer to the output shaft.
The ranges shown for continuous and short-time operation (red or white area accordingly) are the result of the overlapping of the operation ranges of the 1, 2, and 3 stage gearheads.
The real operating ranges for an n-stage gearhead can be obtained by taking the corresponding torque limits into consideration (lines 5 and 6 on the catalog data sheet). As an example the operating ranges for the 1 and 2 stage gearheads are illustrated in fig. 2. To save space in the catalog data sheet separate illustrations per gearhead stage are not shown.
Availability of Gearheads
- Existing sample orders, which we stopped, will now be released and produced. They will be ready for shipment from week 35 (1-stage) and week 38 (multi-stage).
- The 1-stage gearheads can be ordered with the 6 figure part no. as from week 28 and will be available from week 35.
- The 2- and 3-stage gearheads can be ordered with the 6 figure part no. from week 33 and will be
available from week 38.
Internal Autoclave Tests (Motor and Gearhead)
Motors and motor-gear combinations were tested for up to 1,000 steam sterilizing cycles. The following explains in detail the internal autoclave tests for the EC 13 / EC Size 5 with and without gearheads:
The tests are made according to the following standards:
o IEC 60068-2-66 HAST-Test
o JEDEC JESD22-A102-C
o EN 13060 (Sterilisation)
- The tests are made using an autoclave with vacuum phase from Systec (Series DX). The test samples are placed unpacked and without additional protection in the autoclave.
- Three vacuum cycles are made at the beginning so that the test sample is also dampened on the inside.
- The sterilisation atmosphere is built up with steam which remains constant for 20 minutes: +134°C, 100% relative humidity, 2.3bar.
- Cooling to +70°C (cooling down to room temperature would take much longer) and drying, whereby the test samples remain in the autoclave. A complete cycle takes a little longer than 1 hour.
- After 20 - 50 cycles the test samples are removed from the autoclave and tested: visual check, motor data, noise and vibration.
- Typically 5 test samples are tested together. In case of extensive design changes the tests are repeated.
- A test with over 1,000 cycles takes approx. 3 months.
- All test samples with shaft seal have, until now, achieved 500 cycles. The majority of them even 1,000 cycles.