Handle System - Partner K950 Active Technical Description

Handle system

Ergonomics have top priority in the design of every
Partner cutter. In practical terms, this means the
machine must be comfortable and safe to use. A well-
built tool will not tire or burden its operator. More work
gets done and the risk of injuries is minimised, both in
the long and the short term.
The distance between the handles is important for
overall ergonomics. A short gap means the operator
must use greater force to advance and hold the machine
on course. If the distance is too great, the machine is
difficult to control.
The ideal
distance, as on
the K950/K1250
Active, corres-
ponds closely to
the shoulder
width of the
user.
Handle grips in line with the
cutter blade
A design in which the line of grip
on the front and rear handles is
aligned with the cutter blade,
gives the best conditions for safe
and efficient cutting. The cutter
blade is automatically pressed
straight down into the cutting
groove, and the cut is straight.
Crooked cutting grooves waste
power and impose extra wear on
the cutter's frame and segment.
Horizontal cutting is more difficult compared to the
more common vertical cutting. In vertical cutting, most
of the machine's weight is exerted on the object being
cut and the feed pressure is applied on the front handle.
In horizontal cutting, however, the operator has to
support the machine. The front handle's forward-positio-
ned grip in the horizontal position shifts the weight to the
rear handle, thus creating better balance. The operator
can easily and comfortably provide feed pressure with
his body against the air filter housing, with the support
of the handle arch.
Vibration suppression
In prolonged use, vibrating handles cause injuries to the
blood vessels in the hands (TVD, often termed "white
fingers"). In brief use, vibration results in impaired sensi-
tivity and muscle strength in the hands which, apart from
the discomfort, also heightens the risk of accidents.
Suppressing vibration in the handle system is some-
thing of a designer's balancing act. A firm handle system
would, in theory, provide perfect contact and control of
the machine, if we disregard the harmful effects of vibra-
tion. Maximum vibration suppression, on the other hand,
would permit considerable movement between handle
and machine which would result in poor control over the
machine during cutting. A good handle system is always
a matter of combining optimum vibration suppression
with good control over the machine.
New design
The K950/K1250 Active differ from other Partner cutters
in that the handle unit is integrated with the fuel tank and
base plate, at the front of which there is a vibration-
suppression element. With this design, weight has been
transferred to the handle system. The greater mass in
the handle unit considerably cuts vibration levels, parti-
cularly in the case of high-frequency vibration.
The four damper elements consist
of steel springs with a rubber
damper pad at the handle arch.
The dampers are placed as far
from each other as possible, thus
achieving a good compromise
between vibration suppression
and operating convenience.
Safe starting position
The rear handle
on Partner cutters
is designed to
accommodate a
large boot, ideal
for locking the
machine in a safe
starting position.
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