DENTSPLY AUSTENAL ELECTROMATIC-4, Руководство по эксплуатации

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INTRODUCTION
The ELECTROMATIC - 4 has been designed and built to consistently produce metallurgical sound precision
castings through a series of rigidly controlled operations, automatically or manually performed. Casting with the
Electromatic - 4 consists of four basic operations:
1. Placing preheated crucible and mold in their appropriate holders
2. Induction melting of the alloy
3. Centrifugal casting of the molten alloy into the mold
4. Removal of the crucible and mold
Phases 2 and 3 are accomplished through a complex electro-mechanical system. Induction melting is accomplished
by creating a rapidly alternating magnetic field, which causes the alloy in the crucible to absorb energy and
melt. The high frequency field is developed in a water-cooled coil, which surrounds the crucible and is produced
by a generator, which oscillates at approximately 500 kHz (thousands of cycles per second).
The START and STOP push buttons, the ON indicator and the circuit breaker form a circuit that will provide
power to the Generator if the Melt Coil is in the UP and LOCK position, and to the Centrifuge Motor if the Melt
Coil is in the DOWN position. Pressing the START push button will latch the circuit, which will be indicated by the
ON indicator, if all the interlocks are operating normally. The circuit will automatically unlatch in the event of a
power failure. This minimizes the possibility of an accident if the power is suddenly restored. If an overload
occurs within the Melt Circuit during the melting cycle, the overload circuit will turn off and unlatch the operation.
Pressing the STOP push button will unlatch the circuit during Melting or Centrifuging and discontinue power to the
generator or the centrifuge motor correspondingly. During the centrifuge operation the cover is locked and can
not be opened until the arm comes to a complete stop. With the unit in the Automatic mode, control of the
casting temperature is maintained by the Optical Radiation Pyrometer. This detector senses both visible light and
infrared radiation coming directly from the alloy, or carbon insert. Its signal is fed to a solid state Temperature
Controller. When the molten alloy reaches a preset temperature, the power to the Melt Coil is cycled ON and
OFF, automatically maintaining the alloy at the selected temperature prior to casting. This holding cycle is called
“soaking”. Soaking times can be set from 0 to 60 seconds, and is engaged by momentarily pressing the SOAK
TIMER ENGAGE push button during melting or after the alloy has reached temperature. When the Soak Timer
completes the cycle and the Centrifuge Cover is closed, the Melt Coil drops, the casting arm revolves clock-wise
and the molten alloy will be centrifugally cast into the mold. The centrifuge will spin for 30 seconds and
automatically stop. When the unit is used in the Manual mode, control of the casting operation is dependent on
the operator observing the alloy in the crucible and manually cycling the Start and Stop push buttons maintains
proper temperature. When the alloy is ready to cast, place the investment ring in the cradle and close the
Centrifuge Cover. Continue to cycle the Start and Stop push buttons to maintain the desired casting temperature.
With the Start and Stop circuit latched, activate the Coil Release switch. This will drop the Melt Coil, the casting
arm will revolve and the molten alloy will be centrifugally cast into the mold. The centrifuge will spin for 30
seconds. When the centrifuge is in operation, in either Automatic or Manual mode, the Coil Release Switch will
be inoperative until power to the centrifuge motor has been discontinued.
Electromatic - 4
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