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Thermo Fisher Scientific
Operation Manual HM550
e microtome of this cryostat is a rustproof rotary microtome.
e cutting movement is carried out by turning the hand wheel.
e rotary movement results in the vertical and horizontal movement of
the specimen clamp.
Sectioning is carried out by knives or blades, which must be adjusted
and fixed on the knife carrier.
With the downward movement of the specimen, sectioning is carried
out (cutting movement).
e upward return travel of the specimen is carried out by turning the
hand wheel further in a clockwise direction. During this return travel,
the specimen clamping is drawn back automatically to protect knife and
specimen. If required, the function retraction can be turned off.
e selected section thickness is delivered at the upper reversal point of
the return travel.
e number of the sections made can be shown on the section counter
on the display. After each downward movement of the specimen holder,
the number on the section counter increases by 1.
e sum of the sections carried out can also be seen on the display.
For this, trimming values and sectioning values are added up. Section
counter and sum of section thicknesses can be reset to zero at any time
by means of the RESET-button.
Moreover, the remaining travel to the front end position can also be
shown on the display. e remaining travel, which is still available for
sectioning, is shown in microns. When the specimen clamping is in the
back end position, the display shows 28 000 µm. is number decreas-
es, the further the specimen clamping is moved towards the front, i.e. in
the direction of the blade.
Cutting movement
Theory of operation
Cutting movement
