Dishwashing machine

Abstract

A dishwashing machine executes a washing or rinsing step of jetting hot water accumulated in a tank into a washing room. The dishwashing machine includes a heater for heating the hot water in the tank, a temperature sensor for measuring the temperature of the hot water in the tank, and a heater control unit for controlling the heater so that the hot-water temperature in the tank becomes a set temperature, based on the measured value of the temperature sensor. The heater control unit is capable of controlling the heater so that the hot-water temperature in the tank becomes a waiting temperature that is lower than the set temperature, in a quiescent operating state in which the washing or rinsing step is not executed.

1 . A dishwashing machine capable of executing a washing or rinsing step of jetting hot water accumulated in a tank into a washing room, comprising:
 a heater for heating the hot water in the tank;   a temperature sensor for measuring the temperature of the hot water in the tank; and   a heater control unit for controlling the heater so that the hot-water temperature in the tank becomes a set temperature, based on the measured value of the temperature sensor,   wherein the heater control unit is capable of controlling the heater so that the hot-water temperature in the tank becomes a waiting temperature that is lower than the set temperature, in a quiescent operating state in which the washing or rinsing step is not executed.   
     
     
         2 . The dishwashing machine according to  claim 1 ,
 wherein the heater control unit, if being provided with no operation-start signal and the quiescent operating state has continued for a predetermined time period, controls the heater so that the hot-water temperature in the tank becomes the waiting temperature.   
     
     
         3 . The dishwashing machine according to  claim 1 ,
 wherein the heater control unit, if being provided with the operation-start signal while controlling the hot-water temperature in the tank to be the waiting-temperature, extends washing time.   
     
     
         4 . The dishwashing machine according to  claim 3 ,
 wherein the heater control unit, if being provided with the operation-start signal while controlling the hot-water temperature in the tank to be the waiting temperature, extends the washing time by preset extension time.   
     
     
         5 . The dishwashing machine according to  claim 3 ,
 wherein the heater control unit, if being provided with the operation-start signal while controlling the hot-water temperature in the tank to be the waiting temperature, extends the washing time until the hot-water temperature in the tank becomes a preset washing-time-finishing temperature.   
     
     
         6 . The dishwashing machine according to  claim 5 ,
 wherein the washing-time-finishing temperature is set at the start of the rinsing step so that the hot-water temperature in the tank for rinsing becomes the set temperature.   
     
     
         7 . The dishwashing machine according to  claim 3 ,
 wherein the heater control unit, if being provided with the operation-start signal while controlling the hot-water temperature in the tank for rinsing to be the waiting temperature, extends the washing time for preset number of extended times of operation.   
     
     
         8 . The dishwashing machine according to  claim 1 ,
 wherein the heater control unit, if being provided with the operation-start signal while controlling the hot-water temperature in the tank to be the waiting temperature, stops the heater when the hot-water temperature in the tank reaches a preset heater-stopping temperature; and   the heater-stopping temperature is set so that the hot-water temperature in the tank becomes the set temperature by the thermal inertia of the stopped heater.   
     
     
         9 . The dishwashing machine according to  claim 1 ,
 wherein the heater control unit, while controlling the hot-water temperature in the tank to be the waiting temperature, changes the waiting temperature into a lower waiting temperature in response to period of duration time of the quiescent operating state.   
     
     
         10 . The dishwashing machine according to  claim 1 ,
 wherein the heater control unit, if being provided with the operation-start signal while controlling the hot-water temperature in the tank to be the waiting temperature, changes the waiting temperature into a higher temperature, and then elevates the waiting temperature to be close to the set temperature in response to input frequency of the operation-start signal.   
     
     
         11 . The dishwashing machine according to  claim 2 , further comprising:
 a motion sensor for detecting motion in surroundings of the dishwashing machine,   wherein the heater control unit, if the motion sensor does not detect the motion within a predetermined time period, controls the heater so that the hot-water temperature in the tank becomes the waiting temperature.   
     
     
         12 . The dishwashing machine according to  claim 2 , further comprising:
 an illuminance sensor for measuring illuminance in surroundings of the dishwashing machine,   wherein the heater control unit, if the illuminance sensor does not measure illuminance having a predetermined value or more within the predetermined time period, controls the heater so that the hot-water temperature in the tank becomes the waiting temperature.   
     
     
         13 . The dishwashing machine according to  claim 2 , further comprising:
 a sound sensing sensor for sensing sound in surroundings of the dishwashing machine,   wherein the heater control unit, if the sound sensing sensor does not sense sound having a predetermined value or more within the predetermined time period, controls the heater so that the hot-water temperature in the tank becomes the waiting temperature.   
     
     
         14 . The dishwashing machine according to  claim 2 , further comprising:
 a control section for outputting a signal to the heater control unit, for controlling the heater so that the hot-water temperature in the tank becomes the waiting temperature,   wherein the heater control unit, if the control section is operated, controls the heater so that the hot-water temperature in the tank becomes the waiting temperature even if the predetermined time period does not elapse.