초록 ▼

An electronic timer activates a switch circuit so as to connect electrically a heating device and a power supplying unit of a coffee maker for a predetermined brewing period in order to heat water that is supplied to a filter basket and that comes from a water reservoir of the coffee maker. The proc

An electronic timer activates a switch circuit so as to connect electrically a heating device and a power supplying unit of a coffee maker for a predetermined brewing period in order to heat water that is supplied to a filter basket and that comes from a water reservoir of the coffee maker. The processing unit activates the switch circuit for the predetermined brewing period when the brewing time coincides with the current time. A temperature sensing unit includes a temperature-controlled switch which connects the switch circuit to the heating device when temperature of the heating device is below a lower limit of a predetermined temperature range, and which disconnects the switch circuit from the heating device when the temperature is above an upper limit of the temperature range. The temperature sensing unit further includes a signal generating circuit which interconnects the temperature-controlled switch and the processing unit. The processing unit is prevented from subsequent activation of the switch circuit when duration of a switch-off signal from the signal generating circuit does not exceed a predetermined critical time period.

대표청구항 ▼

An electronic timer for activating a switch circuit so as to connect electrically a heating device and a power supplying unit of a coffee maker for a predetermined brewing period, the heating device being used to heat water that is supplied to a filter basket and that comes from a water reservoir of

An electronic timer for activating a switch circuit so as to connect electrically a heating device and a power supplying unit of a coffee maker for a predetermined brewing period, the heating device being used to heat water that is supplied to a filter basket and that comes from a water reservoir of the coffee maker, said electronic timer comprising: processing means having an internal clock for registering a current time of day, and an internal register for storing a preset brewing time, said processing means being operable in an automatic mode, wherein said processing means is adapted to activate the switch circuit for the predetermined brewing period so as to heat the water that is supplied to the filter basket when the brewing time coincides with the current time; and temperature sensing means including a temperature-controlled switch which is adapted to connect the switch circuit to the heating device so as to permit activation of the heating device when temperature of the heating device is below a lower limit of a predetermined temperature range and to disconnect the switch circuit from the heating device so as to deactivate the heating device when the temperature of the heating device is above an upper limit of the predetermined temperature range, said temperature sensing means further including a signal generating circuit which interconnects said temperature-controlled switch and said processing means and which is adapted to be connected to the power supplying unit via said temperature-controlled switch, said signal generating circuit generating a switch status signal received by said processing means, the switch status signal being a switch-on signal when said temperature-controlled switch connects the switch circuit to the heating device, and being a switch-off signal when said temperature-controlled switch disconnects the switch circuit from the heating device; said processing means further including means for preventing subsequent activation of the switch circuit when duration of the switch-off signal from said signal generating circuit does not exceed a predetermined critical time period.