Method and arrangement for the energy-saving operation of dishwashers

• US 20090151750A1
• Filed: 08/25/2005
• Published: 06/18/2009
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: Meiko Maschinenbau GmbH & Company KG (Stiftung Oskar Und Rosel Meier)
• Original Assignee: Meiko Maschinenbau GmbH & Company KG (Stiftung Oskar Und Rosel Meier)
• Inventors: Zapf, Dietmar, Streb, Michael, Eggs, Marcus, Ecker, Engelbert
• Granted Patent: US 7,884,498 B2
• Time in Patent Office: Days
• US Class Current: 134/18
• CPC Class Codes: A47L 15/0047 Energy or water consumption, e.g. by saving energy or water
• CPC Class Codes: A47L 15/0078 with a plurality of fluid recirculation arrangements, e.g. with separated washing liquid and rinsing liquid recirculation circuits
• CPC Class Codes: A47L 15/245 the dishes being placed directly on the conveyors, i.e. not in dish racks A47L15/242 takes precedence
• CPC Class Codes: A47L 15/247 Details specific to conveyor-type machines, e.g. curtains
• CPC Class Codes: A47L 2401/12 Water temperature
• CPC Class Codes: A47L 2501/06 Water heaters

Abstract

The energy-saving operation of dishwashers (110; 410) plays an important role, in particular for larger enterprises, e.g. for the canteens of hospitals or large enterprises, and in the medical disinfection field. The invention thus discloses a method and a device, in which a total maximum electric output is assigned to a group of electric consumer elements (14, 15, 18, 19, 22, 23, 26, 33; 418, 420, 432, 438) of a dishwasher (110; 410). In addition, at least two output levels are assigned to each electric consumer element (14, 15, 18, 19, 22, 23, 26, 33; 418, 420, 432, 438) of said group. An optimum combination of output levels is then selected in a requirement determination step, based on an operational state B of the dishwasher (119), whereby for each consumer element (14, 15, 18, 19, 22, 23, 26, 33; 418, 420, 432, 438) the selected output level is adapted to the output requirement of the consumer element (14, 15, 18, 19, 22, 23, 26, 33; 418, 420, 432, 438) in operational state B and the total output of all consumer elements (14, 15, 18, 19, 22, 23, 26, 33; 418, 420, 432, 438) does not exceed the maximum electric total output. The operation of the dishwasher (110; 410) can also be divided into three phases, a start phase, an activation phase and a load control phase. The output levels of the individual consumer elements (14, 15, 18, 19, 22, 23, 26, 33; 418, 420, 432, 438) are optimally adapted in accordance with the requirements in said operating phases, thus allowing a response to be made to any fluctuations in the operational state. The inventive method permits significant energy savings to be made in comparison to conventional methods for controlling dishwashers (110; 410) and leads to a more rapid attainment of a ready status of the dishwasher (110; 410) upon activation.

Claims

1. A method for energy-saving operation of a dishwasher (110;

410), in particular for washing dishes (9;

414) or medical appliances, with the dishwasher (110;

410) having a total number N≧

2 of electrical load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438), having the following steps;

a) a group of n electrical load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) is assigned a maximum electrical total power p_max;

b) each electrical load element i in the group of n electrical load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) is assigned a finite number m_i of discrete electrical power levels p_ij where m₁≧

2;

with there being a maximum power level p_imax for each i, where p_ij≧

p_imax,

where the sum of all maximum power levels p_imax form a worst total power

2. The method as claimed in the preceding claim, characterized in that a power level p_ik exists for each electrical load i (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438), where 0<

k≦

m_i and where p_ik=0.

3. The method as claimed in claim 1, characterized in that m_i=3 for all i.

4. The method as claimed in claim 1, characterized in that the following method steps are additionally carried out:

e) the dishwasher (110;

410) is started, as a result of which a starting phase begins;

f) at least one temperature of at least one washing liquid, in particular a temperature of water in at least one water tank (13, 17, 21;

416, 426) and/or water circuit, is detected;

g) the at least one washing liquid is heated,

where at least one heating element (14, 18, 22, 26;

418, 432) which heats the washing liquid and forms the load element 1 where 1ε

{1, . . . , n} is operated at the maximum power level p_imax associated with this heating element (14, 18, 22, 26;

418, 432), and

where at least one load element q (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) which is not the same as the heating element (14, 18, 22, 26;

418, 432) and where qε

{1, . . . , n} and q≠

1 is operated at a lower power than the regular power level p_qreg associated with this load element q (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438); and

h) as soon as the at least one temperature of the at least one washing liquid has reached or exceeded a predetermined nominal value, a switched-on phase is started,

where the power of all the load elements i (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) is set to the respectively associated regular power level p_ireg.

5. The method as claimed in the preceding claim, having the following additional step:

i) at least one operating state variable is detected;

j) at least one operating state variable is allocated a nominal value; and

k) as soon as the value of the at least one operating state variable differs from the respectively associated nominal value by more than a predetermined tolerance, a load regulation phase is started.

6. The method as claimed in the preceding claim, characterized in that, in the load regulation phase, at least one load element r (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) where r {1, . . . , n} and which influences the at least one operating state variable which differs by more than the predetermined tolerance from its nominal value is operated at a power level which differs from its regular power level p_rreg, until the at least one operating state variable once again assumes a value which differs by not more than the predetermined tolerance from its nominal value.

7. The method as claimed in claim 1, characterized in that, in method step c), each load element (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) is allocated a priority, and in that the optimum combination of the power levels pij(B) is determined taking into account the priorities of the load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438).

8. The method as claimed in the preceding claim, characterized in that heating elements (14, 18, 22;

418, 432) which heat washing liquid, in particular water in at least one water tank (13, 17, 21;

416, 426) and/or water circuit, is allocated a higher priority than other loads.

9. The method as claimed in claim 1, characterized in that all of the operating states B are characterized by an operating phase variable F and/or by a plurality of operating state variables,

where the operating state variable F can assume at least three discrete values (F₁, F₂, F₃),

where F₁ denotes a starting phase for operation of the dishwasher (110;

410),

where F₂ denotes a switched-on phase for operation of the dishwasher (110;

410), and

where F₃ denotes the load regulation phase for operation of the dishwasher (110;

410).

14. The apparatus as claimed in claim 1, characterized in that the means c) (310) for selection of an optimum combination of power levels p_ij(B) have means (310) for allocation of a priority to each load element (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) as a function of an operating state B of the dishwasher (110;

410), where the optimum combination of the power levels pij(B) is determined taking into account the priorities of the load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438).

15. The apparatus as claimed in claim 1, characterized in that the dishwasher is a multiple tank dishwasher (110).

16. The apparatus as claimed in claim 1, characterized in that the means b) (310, 332, 334, 336, 338, 340;

452, 454, 456, 458) for assignment of a finite number mi of discrete electrical power levels pij to each electrical load element (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) and/or the means c) (310) for selection of an optimum combination of power levels p_ij(B) as a function of an operating state B of the dishwasher (110;

410) have/has a look-up table (314) and/or an electronic table.

17. A computer program having program code means in order to carry out a method as claimed in claim 1, when the computer program is run on a computer (310) or a computer network.

18. A computer program having program code means as claimed in the preceding claim, which program code means are stored on a computer-legible data storage medium (314).

10. An apparatus for energy-saving operation of a dishwasher (110;

410), in particular for washing dishes (9;

414) or medical appliances, with the dishwasher (110;

410) having a total number N≧

2 of electrical load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438), having;

a) means (310) for assignment of a maximum electrical total power p_max to a group of n electrical load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438);

b) means (310, 332, 334, 336, 338, 340;

452, 454, 456, 458) for assignment of a finite number m_i of discrete electrical power levels p_ij to each electrical load element i in the group of n electrical load elements (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438),

with there being a maximum power level p_imax for each i, where p_ij≦

p_max,

where the sum of all maximum power levels p_imax form a worst total power

11. The apparatus as claimed in the preceding claim, additionally having:

e) means (310) for starting the dishwasher (110;

410) by which means a starting phase is started;

f) means (318, 320) for detection of at least one temperature of at least one washing liquid, in particular a temperature of water in at least one water tank (13, 17, 21;

416, 430) and/or water circuit;

g) at least one heating element (14, 18, 22, 26;

418, 432), which heats the at least one washing liquid and forms the load element 1 (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) where 1ε

{1, . . . , n}, as well as means (322, 324, 326, 328;

448, 450) for operation of the at least one heating element (14, 18, 22, 26;

418, 432) at the maximum power level p_imax associated with this heating element, as well as means (322, 324, 326, 328, 330;

444, 446, 448, 450) for operation of at least one load element q (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438), which is not the same as the at least one heating element, where qε

{1, . . . , n} and q ≠

1 at a lower power than the regular power level p_qreg associated with this load element q (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438); and

h) means (310) for starting a switched-on phase as soon as the at least one temperature of the at least one washing liquid has reached or exceeded a predetermined nominal value,

where the power of all the load elements i (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) is set to the respectively associated regular power level p_ireg.

12. The apparatus as claimed in the preceding claim, additionally having:

i) means (318) for detection of at least one operating state variable;

l) means (310) for assignment of in each case one nominal value to at least one operating state variable; and

m) means (310) for starting a load regulation phase as soon as the value of the at least one operating state variable differs by more than a predetermined tolerance from the respectively associated nominal value.

13. The apparatus as claimed in the preceding claim, having additional means (322, 324, 326, 328, 330;

444, 446, 448, 450) for operation of at least one load element r (14, 15, 18, 19, 22, 23, 26, 33;

418, 420, 432, 438) where rε

{1, . . . , n} which influences the at least one operating state variable which differs by more than the predetermined tolerance from its nominal value at a power level, which differs from its regular power level p_rreg, in the load regulation phase, until the at least one operating state variable once again assumes a value which differs from its nominal value by not more than the predetermined tolerance.