Refrigeration unit

1. Cooling unit ( 1 ) for a service trolley for use in an aircraft or train, the cooling unit comprising a drawer, and the drawer comprising:

a partition ( 29 ), which partition separates a warm ( 30 ) and cold zone ( 31 ) in the drawer;

one or more Peltier elements ( 42 ) with a side ( 43 ) that gives off heat and a side ( 44 ) that takes up heat;

one or more first fans ( 32 ) provided in the cold zone ( 31 ) for feeding air to be cooled through the cold zone ( 31 );

one or more second fans ( 33 ) provided in the warm zone ( 30 ) for feeding air removing heat through the warm zone ( 30 ); characterised in that the drawer is a box essentially closed by walls ( 3 , 4 , 5 , 6 , 7 ), in that the partition comprises a layer ( 29 ) of heat-insulating material and in that the one or more Peltier elements ( 42 ) are located in the heat-insulating layer ( 29 ) with the side giving off heat facing the warm zone ( 30 ) and with the side taking up heat facing the cold zone ( 31 ), and wherein one or more heat-conducting first heat exchangers ( 35 ) joined to the cold side ( 44 ) of the Peltier elements ( 42 ) are provided in the cold zone ( 31 ) and one or more heat-conducting second heat exchangers ( 34 ) joined to the warm side ( 43 ) of the Peltier elements ( 42 ) are provided in the warm zone ( 30 ), the first heat exchangers ( 35 ), the heat-insulating layer ( 29 ) and the walls ( 3 , 4 , 5 , 6 , 7 ) of the drawer dividing the cold zone ( 31 ) into a first inlet chamber ( 39 ) with a first inlet opening ( 36 ) into the service trolley and into a first outlet chamber ( 38 ) with a first outlet opening ( 37 ) into the service trolley.

2. Cooling unit according to claim 1 , wherein the second heat exchanger ( 34 ), the heat-insulating layer ( 29 ) and the walls ( 3 , 4 , 5 , 6 , 7 ) of the drawer divide the warm zone ( 30 ) into a second inlet chamber ( 40 ) with a second inlet ( 11 ) and a second outlet chamber ( 14 ) with a second outlet ( 12 ), the orifices of the second inlet ( 11 ) and the second outlet ( 12 ) being in the side walls ( 3 , 4 , 5 ) of the drawer, preferably both being in the same side wall ( 3 , 4 , 5 ), such as the rear wall ( 4 ).

3. Cooling unit according to claim 1 , characterised in that the orifices of the first inlet ( 36 ) and the first outlet ( 37 ) both extend in a horizontal plane, the first outlet ( 37 ) preferably being so constructed that the outflow direction is at an angle and oriented away from the vertical axis through the first inlet ( 36 ).

4. Cooling unit according to claim 1 , wherein electrical contacts ( 14 ) are provided on the outside of the drawer, which contacts are connected to the Peltier elements ( 42 ) in an electrically conducting manner.

5. Service trolley for use in an aircraft or train, the service trolley comprising a housing with a base, a ceiling, upright side walls ( 22 , 23 ) as well as a door ( 21 ) for access to the interior of the housing, characterised in that the service trolley contains a cooling unit ( 1 ) according to claim 1 placed in the housing.

6. Service trolley according to claim 5 , wherein the interior of the housing and the interior of the warm zone ( 30 ) of the drawer are separated from one another by a drawer wall ( 7 ).

7. Service trolley according to claim 5 , wherein two opposing side walls of the housing are provided on the inside with a multiplicity of pairs of drawer rails located above one another and wherein the drawer of the cooling unit bears on one or more pairs of drawer rails.

8. Service trolley according to claim 5 , wherein the cooling unit ( 1 ) is placed in the top of the housing.

9. Service trolley according to claim 5 , wherein the second outlet ( 12 ) protrudes from the rear wall ( 24 ) of the service trolley and wherein the orifice of the second inlet is closer to the service trolley than the orifice of the second outlet ( 12 ).

10. Service trolley according to claim 5 , wherein the service trolley is provided with electrical contacts on the outside that can be connected to the Peltier elements ( 42 ) of the cooling unit ( 1 ) in an electrically conducting manner.

11. Service trolley according to claim 5 , which service trolley ( 1 ) is provided with one or more temperature sensors and control means for controlling the Peltier elements ( 42 ) depending on the signals emitted by the temperature sensors.

12. Service trolley intended for use with a cooling unit ( 1 ) according to claim 1 .

13. Combination of a service trolley according to claim 5 and a wall ( 16 ), wherein the wall ( 16 ) is provided on the inside with at least one channel ( 19 ) for supply or discharge, preferably discharge, of air and wherein at least one opening ( 26 ) that opens into said channel ( 19 ) is provided in the wall ( 15 ), to which opening the second inlet ( 11 ) or second outlet ( 12 ), respectively, of the cooling unit ( 1 ) can be connected.

14. Combination according to claim 13 , wherein the wall ( 16 ) comprises two wall panels ( 17 , 18 ) with a cavity ( 19 ) forming the at least one channel between them.

15. Rack ( 60 ) provided with, or at least intended for, a multiplicity of cooling units ( 1 ) according to claim 1 , wherein the rack ( 60 ) comprises a multiplicity of seats ( 61 ), each of which is suitable for accommodating at least part of a cooling unit ( 1 ), wherein each seat ( 51 ) is provided with contact means ( 62 ) that, when the cooling unit has been inserted into said seat, are electrically connected to electrical contacts ( 14 ) provided on the cooling unit, and wherein the contact means ( 62 ) are connected to testing means ( 64 ) for testing the operation of the Peltier elements ( 42 ) and/or fans ( 32 , 33 ) and br control means of a cooling unit ( 1 ) inserted in the said seat ( 51 ), and wherein the testing means ( 64 ) are connected to indicator means ( 63 ) for giving an indication that is representative of whether or not the cooling unit ( 1 ) is functioning properly.

16. Rack ( 60 ) according to claim 15 , wherein the indicator means ( 63 ) comprise a light source that can be switched on/off per seat ( 51 ), which light source is preferably on when the cooling unit is functioning properly.

17. Aircraft or train containing a cooling unit according to claim 1 .

18. Cooling unit according to claim 2 , characterised in that the orifices of the first inlet ( 36 ) and the first outlet ( 37 ) both extend in a horizontal plane, the first outlet ( 37 ) preferably being so constructed that the outflow direction is at an angle and oriented away from the vertical axis through the first inlet ( 36 ).

19. Service trolley according to claim 6 , wherein two opposing side walls of the housing are provided on the inside with a multiplicity of pairs of drawer rails located above one another and wherein the drawer of the cooling unit bears on one or more pairs of drawer rails.