Transcript Pertemuan 9

Pertemuan 9
Principles of Work Design : Tools
Use a power grip for tasks
requiring force and pinch
grips for tasks requiring
presicion
( Sumber : Niebel& Freivalds, ( 2003 )
Power Grip
Power grip is used for power or for holding
heavy objects. However, the more of fingers or
the thumb deviate from the cylindrical grip, the
less force is produced and the greater the
precision that can be provided.
Ex : Holding a light hammer as in tacking, the
thumb may deviate from opposing the fingers to
aligning with the handle.
( Sumber : Niebel& Freivalds, ( 2003 )
Pinch Grip
Is used for control or precision. In a pinch
grip, the item is held between the distal
ends of one or more fingers and the
opposing thumb (the thumb is sometimes
omitted)
Ex : holding a key
( Sumber : Niebel& Freivalds, ( 2003 )
Handle design
Shown here is a conventional paint scraper (a) that presser in the
ulnar artery, modify handle (b) that rests on the tough tissues
between thumb and index finger and prevents pressure on the critical
areas of the hand. Note that the handle extends beyond the base of
the palm.
Use The Proper Configuration And
Orientation of Power Tools
In a power drill or other power tools, the major
function of the operator is to hold, stabilize, and
monitor the tool against a workpiece, while the
tools perform the main effort of the job. Although
the operator may at the times need to shift or
orient the tool, the main function for the operator is
effectively to grasp and hold the tool.
( Sumber : Niebel& Freivalds, ( 2003 )
Use The Proper Configuration
And Orientation of Power Tools
Handle configuration is also important, with the
choices being pistol-grip, in-line, or right –angle.
As a rule of thumb, in-line and right-angle are
best for tight-ening downward on a horizontal
surface, while pistol-grips are best for tightening
on a vertical surface, with the aim being to
obtain a standing posture with a straight back,
upper arms hanging down, and the wrist
straight (see figure).
( Sumber : Niebel& Freivalds, ( 2003 )
Use The Proper Configuration
And Orientation of Power Tools
Another important factor is center of gravity.
If it is too far forward in the body of tool, a
turning moment us created, which must be
overcome by the muscles of the hand and
forearm. This requires muscular effort
additional to that required for holding,
positioning, and pushing the drill into the
workpiece.
( Sumber : Niebel& Freivalds, ( 2003 )