초록 ▼

An automatically controlled recirculating high velocity hot air sterilization device includes a housing having a sterilization chamber with a temperature sensor mounted therein, a hot air plenum including a blower in fluid communication with a heating element and sterilization chamber for inputting

An automatically controlled recirculating high velocity hot air sterilization device includes a housing having a sterilization chamber with a temperature sensor mounted therein, a hot air plenum including a blower in fluid communication with a heating element and sterilization chamber for inputting hor air into and receiving hot air from the sterilization chamber for recirculation, and a control chamber having a temperature sensing circuit connected to the temperature circuit for producing electrical inputs representative of the sterilization chamber temperature, power circuits connected to the heating element and blower, a controller connected to the temperature sensing circuit for monitoring the temperature, and to the heating element and blower circuits for controlling their operation, and a control panel including cycle selection switches for operation, an on/off switch, and temperature and timer/error displays. The controller is designed for monitoring the cycle selection switches and on/off switch, for controlling operation of the heating element, blower and timer for the cycle selected, for monitoring the temperature, for starting the timer when the temperature rises to the required temperature, for restarting the timer should the temperature fall below the required temperature during a cycle, for shutting down the device when a catastrophic failure occurs and for outputting an error signal together with problem information for display.

대표청구항 ▼

An automatically controlled sterilization device for nondestructively sterilizing medical instruments comprising: a sterilization chamber, a temperature sensing means mounted in the sterilization chamber for outputting temperature indicating signals; a plenum chamber, a blower means and a heater mea

An automatically controlled sterilization device for nondestructively sterilizing medical instruments comprising: a sterilization chamber, a temperature sensing means mounted in the sterilization chamber for outputting temperature indicating signals; a plenum chamber, a blower means and a heater means mounted in operative association in the plenum chamber, for forcing hot air into the sterilization chamber; a control chamber, a programmable controller means mounted in the control chamber for controlling operation of the sterilization device at a sterilization temperature between about 350°F. and 400°F.; an on/off switch means connected to the programmable controller for initializing the sterilization device; and an ac circuit means for connection to a source of ac power, said ac circuit means including a thyristor connected to the heater means, a switch means connected to the blower means and thyristor, said thyristor having a triggering gate for selectively pulsing on the thyristor, an ac zero crossing detector means connected to the ac power source for determining zero crossings for each ac cycle, and logic means connected to the zero crossing detector means for producing interrupt signals for the programmable controller indicative of zero current crossings and corresponding turn off of the ac working current; and wherein the programmable controller includes: a first instruction means including means for monitoring the on/off switch means for selectively supplying ac working current to the blower means and thyristor, a nonmaskable interrupt means responsive to the interrupt signals of the logic means for interrupting the first instruction means for said second instruction means, a second instruction means including an ac working current duty cycle determining means connected to the temperature sensing means for producing working current duty cycle information first for a 100% duty cycle for minimizing the time required to raise the temperature in the sterilization chamber up to a selected sterilization temperature and thereafter to maintain the temperature, timing means responsive to the zero crossing interrupts and duty cycle information for determining ac cycle quadrants and time to issue a control pulse to the thyristor\s triggering gate for enabling the thyristor to begin each ac working current duty cycle at a time for enabling completion of the duty cycle on the last zero crossing of each ac cycle, and means for determining any zero crossings occurring during a duty cycle and responsive to corresponding interrupts therefor for pulsing the triggering gate to turn the thyristor back on, whereby the thyristor is triggered on by the timing means timing pulse and remains in until the working current is interrupted at the end of the duty cycle and the thyristor is automatically reset to the off state.