Wintriss Shadow VI, User Manual

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Shadow VI User Manual 1107200
Excerpts from OSHA Regulations and Appendix A page 95
ANSI Standards
Daily Tests in French and English
Extracts from OSHA Regulation 1910.217
OSHA Regulations PMA Interpretation
(d) Muting (bypassing of the protective
function) of such device, during the
upstroke of the press slide, is permitted for
the purpose of parts ejection, circuit
checking and feeding. Top of stroke is the point at which muting shall
cease as it is not possible to set a point on the
downstroke as the exact position where the
hazard of die closing starts.
(e) The safety distance (Ds) from the
sensing field to the point of operation shall
be greater than the distance determined
by the following formula:
Ds = 63 inches/second x Ts where
Ds = minimum safety distance (inches);
63 inches/second = hand speed constant
and
Ts = stopping time of the press measured
at approximately 90° position of crankshaft
rotation (seconds)
Safety distance represents the distance an
operator can move his hand during the time it
takes a press to stop. The internationally
recognized hand reach speed is 63
inches/second.
To determine this safety distance, the stopping
time of the press is measured with some
appropriate measuring device. The
measurement is taken such that the stop signal
is given to the press at the 90 degree point of
the crank position.
Since some stopping time increase must be
accommodated due to braking system deterio-
ration, a percentage factor must be added to
the measured time to obtain the factor for use
in the equation for determining safety distance.
A percentage factor of 20% is recommended
for presses with new brakes or brakes of good
condition. For older brakes, a 10% factor is
recommended.
Example:
Measured stopping time = 0.190 seconds
Time factor = 1.2 x 0.19 = 0.228 seconds
Calculation = 63 x 0.228
Safety distance = 14.4 inches
(f) Guards shall be used to protect all
areas of entry to the point of operation
not protected by the presence-sensing
device. (3) (iii) (f) Great care must be taken to assure
that no access to the die area exists
unguarded.
OSHA 1910.217 (c) (3) (5)
(5) Additional requirements for safe-guarding.
Where the operator feeds or removes parts by
placing one or both hands in the point of
operation, and a two hand control, presence-
sensing device, Type B gate or movable barrier
(on a part revolving clutch) is used for
safeguarding: This paragraph tells the condition under which
a brake monitoring system is required after
November 1, 1975.