Wintriss Shadow 8, Руководство пользователя

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Shadow 8 User Manual 1139300
Extracts from OSHA and ANSI D-19
T includes portions of time that vary by machine type and by the safeguarding device applied. The
following affect the total stopping time:
a) Type of actuator;
i. Full revolution clutch, or machines that cannot be stopped during a machine
cycle. See note 1.
ii. Part revolution friction clutch, or machines that can be stopped at any point in
the machine cycle or anywhere during the hazardous portion of the machine
cycle. See note 2.
iii. Braking mechanism. See note 3.
iv. Stopping capability of the motors and drive. See note 4.
v. Reaction time of valves. See note 5.
b) Reaction time of the machine control system. See note 6.
c) Reaction time of the safeguarding device, including its interface. See note 7.
d) Additional time required by the use of braking performance monitor. See note 8.
Note 1: Full revolution (pin) clutches have one or more engaging points within a rotation of the
flywheel where the clutch can be engaged. Once engaged. the clutch completes a full
revolution or cycle (stroke) before it is disengaged and brought to a stop. After the machine
is tripped by the control system or mechanical treadle, pedal, hand controls or levers, the
clutch typically engages after the flywheel rotates to the engaging position. Therefore, it is
possible that the tripping device could have tripped the clutch just after the flywheel engaging
point has passed and will not engage the clutch until the flywheel has rotated one full
revolution. Assuming that the hazard exists during the closing portion of the cycle or stroke
(provided that no hazards are generated during the opening portion), the time to stop
hazardous motion could take up to one and a half times the time it takes the machine to
complete one cycle (stroke). For clutches with only one engaging point the stopping time, Ts,
is:
Ts = 1.5(Tmc)
Equation (2)
Where:
Tmc
= the time it takes to complete a machine cycle (stroke)
Some clutches have multiple engaging points on the flywheel. Therefore. the clutch has
more than one position where engagement can occur. The equation for calculation of this
time, the stopping time Ts is:
Ts = (1/2 + 1/ N)(Tmc) Equation (3)
Where: N = the number of engaging points on the flywheel
For machines that are tripped (or sequenced) to initiate the machine cycle. which in turn
initiates immediate motion and which cannot be stopped until the completion of the machine
cycle. the stopping time Ts is:
Ts = Thm
Equation (4)
Where:
Thm
= the time, after initiation of motion, until hazardous motion is
completed
Note 2: The stopping time, Ts, of part revolution clutch driven machines or machines that can be
stopped at any point in the machine cycle or stopped anywhere during the hazardous portion
of the machine cycle is equal to the time it takes to stop hazardous motion (see also, Note 3).
If eddy current or other electro-magnetic clutches are used, see Note 4.
Note 3: The stopping time, Ts, is the time it takes to disengage the clutch, the time it takes to apply
the brake and the time it takes the brake to stop motion.
Note 4: The stopping time, Ts, for direct drive, motor driven machines utilizing full voltage motors,
servo systems, vector systems or other variable speed systems, is equal to the time it takes
to stop hazardous motion after a stop command or signal is given to the motor contactor or