EP0863365A2 - Steam generator - Google Patents

Abstract

The steam generator has a steam boiler (1), burner shaft (5) and heat exchange sector (10) with channels (12a, 12b, 12c) connected on one side to a chimney and on the other via a connecting sector to the burner shaft. The connecting sector has a through passage (25), formed by an aperture in one wall (15a, 15b) of the burner shaft and an insert (20). The aperture connects the burner shaft to one or more of the channels of the heat exchange sector, and is partly closed by the insert (20).

Description

The invention relates to a steam generator, in particular for use in the kitchen technology, the one steam boiler, one burner shaft for supplying hot exhaust gases from a burner and at least a heat exchanger section with one or more channels for passing the exhaust gases of the burner and for heat exchange with the liquid in the boiler, wherein the channel or channels of the heat exchanger section on the one hand a trigger and on the other hand with a connecting section connected to the burner shaft and arranged so that the direction of flow the gases flowing from the burner to the flue in the channel or channels different from the direction of flow in the Burner shaft is. Such steam generators are particularly popular an application for cooking devices in canteen kitchen technology.

A steam generator of the type mentioned is from the German Utility model 295 00 595.5 known. With this steam generator a design is used in which the burner shaft with the channels for heat exchange via a simple transverse shaft constant cross-section connected in the steam boiler is trained. This construction is complex and does not lead to optimal redirection of the burner’s exhaust gases, which are fed into the burner shaft to the channels of the Heat exchanger section.

It is the object of the invention to start a steam generator to create the type mentioned, in which the transition of the gas flow from the burner to the channels of the heat exchanger section simple means is solved in a way that is an optimization the flow conditions in the channel or channels of the heat exchanger section enables.

According to the invention this object is achieved in that Steam generator, in particular for use in kitchen technology, which is a steam boiler, a burner shaft for hotter feed Exhaust gases from a burner and at least one heat exchanger section with one or more channels for the passage of the exhaust gases of the burner and for heat exchange with that in the steam boiler located liquid, the channel or channels of the Heat exchanger section on the one hand with a fume cupboard and on the other hand connected to the burner shaft via a connecting section and are arranged so that the flow direction of the gases flowing to the flue in the duct or ducts is different from the direction of flow in the burner shaft, the connecting portion has a passage through a Opening in a wall of the burner shaft, especially in one Side wall of the burner shaft, and an insert is formed the opening opening the burner shaft with one or more channels of the heat exchanger section connects and partially through the Insert is closed.

It can in particular be provided that the gas flow in the Channels of the heat exchanger section opposite to the direction of the gas flow that falls into the burner shaft. Here the burner shaft can be connected to the burner at one end and be closed at the other end, the shaft on the sides except for the culvert or culverts also closed is. Advantageously, the burner shaft in the Steam boiler should be designed so that its walls are simultaneously walls of the boiler and of the liquid in the boiler be cooled. Typically, the channel or channels are the Heat exchanger section and the burner shaft parallel, the Exhaust gases at the transition to the connection section by 180 ° be diverted so that the exhaust gases in the ducts are reversed Flow in the same way as in the burner shaft.

The invention can provide that the opening in a side wall the burner shaft is formed and a mouth on the entry side of the exhaust gases coming from the burner into the burner shaft has and the use with the wall of the burner shaft is connected in the manner of a tongue and groove connection. this makes possible a particularly simple construction in which the use after Kind of a slide on the wall of the burner shaft becomes. The insert preferably has an A or H shape Cross-section. With this construction it is also possible to Cross section of the passage in a simple manner, namely by moving use, and thereby the flow to influence the channel or channels of the heat exchanger section.

The invention can further provide that the use in his Inside has a cavity with an opening in the Passage opens.

It can be provided that the cavity has at least one more Opening, preferably a plurality of openings, having a or more channels at a location downstream from the passage is connected so that part of the flow path in the or the channels is bridged. The insert forms a flow bypass, which allows hot exhaust gases to enter an area of the Channel the heat exchanger in which the exhaust gases are already are cooled and otherwise only a small heat exchange would take place.

The invention can further provide that the heat exchanger section one adjoining the passage downstream Has distribution channel, from which branch off several side channels. One can be arranged between the passage and the side channels Deflection device for deflecting the coming from the passage Exhaust gases are provided in the longitudinal direction of the side channels be. The passage can be designed as a throttle, the gas passing therethrough after passing on the side of the heat exchanger section is relaxed.

According to the invention it is further provided that the steam generator several, preferably substantially identical heat exchanger sections has whose flow system for the exhaust gases the burner through a passage in a wall of the burner shaft is connected to the burner shaft.

The invention can also in particular if the walls of the Burner shaft are at the same time walls of the steam boiler Overheating protection tube in the burner shaft for introducing the exhaust gases of the burner in the burner shaft below the level of the Have liquid levels in the boiler. Is located the mouth of the overheating protection tube is preferably below the minimum liquid level required for the operation of the steam boiler is allowed.

It can in particular be provided that the mouth of the Overheating protection tube just above the level of the or Passages located, which connect the burner shaft with the flow system connect the or the heat exchanger sections.

The invention can also provide that a transfer channel between the walls of the burner shaft and the overheating protection tube is formed and the insert a second, in the transfer channel Mouthful passage which has one or more Channels of a heat exchanger section with the transfer channel at a location of the channel or channels downstream of the first Passage connects so that part of the flow path from bridging the first passage to the discharge through the channels, the first passage being formed outside the transfer duct is.

According to the connection of the burner shaft with the Flow system of the heat exchanger section on simple and elegant Kind solved, while the current conditions in the passage through the choice of a certain form of use let so influence that an optimal distribution of the exhaust gas flow on the channels for heat exchange arises. Especially can the cross section of the passage between the burner shaft and the heat exchanger section are adjusted so that the proportion of the gas flow which is to that from the burner shaft more distant channels flow in the heat exchanger section, is enlarged and thus the distribution of the gas flow to the Channels of the heat exchanger section is made uniform. Since the Can be used independently of the steam boiler and the burner shaft is, further flow-guiding or -limiting Measures by appropriate shaping of the use in can be easily realized.

Fig. 1

zeigt einen Längsschnitt eines erfindungsgemäßen Dampferzeugers.

Fig. 2

zeigt eine Draufsicht des Dampferzeugers gemäß Fig. 1.

Fig. 3

zeigt einen Längsschnitt einer zweiten Ausführungsform des erfindungsgemäßen Dampferzeugers.

Fig. 4

zeigt eine Draufsicht des Dampferzeugers gemäß Fig. 3.

Fig. 5

zeigt einen Längsschnitt einer dritten Ausführungsform des erfindungsgemäßen Dampferzeugers.

Fig. 6

zeigt eine Draufsicht des Dampferzeugers gemäß Fig. 5.

Fig. 7

zeigt einen Längsschnitt einer vierten Ausführungsform der Erfindung

Fig. 8

zeigt eine Draufsicht des Dampferzeugers gemäß Fig. 7.

Further features and advantages of the invention will become apparent from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings.

Fig. 1

shows a longitudinal section of a steam generator according to the invention.

Fig. 2

shows a top view of the steam generator according to FIG. 1.

Fig. 3

shows a longitudinal section of a second embodiment of the steam generator according to the invention.

Fig. 4

shows a top view of the steam generator according to FIG. 3.

Fig. 5

shows a longitudinal section of a third embodiment of the steam generator according to the invention.

Fig. 6

shows a plan view of the steam generator according to FIG. 5.

Fig. 7

shows a longitudinal section of a fourth embodiment of the invention

Fig. 8

shows a top view of the steam generator according to FIG. 7.

In the embodiment according to FIGS. 1 and 2, the steam generator a steam boiler 1 filled with water with an outlet 3, through which steam can be removed. The water level in the Steam boiler is indicated by hatched lines. By doing Steam boiler, a burner shaft 5 is formed, in the over a Overheating protection tube 7 the exhaust gases of a gas burner (not shown) be initiated. These exhaust gases become a heat exchanger section 10 passed, which a plurality of channels 12a, 12b and 12c, which branch off from a distribution channel 14 and through which the exhaust gases of the burner to a fume cupboard (not shown) be directed. Over the walls of channels 12a, 12b, 12c and 14 the exhaust gases exchange heat with the water in the Steam boiler. The distribution channel 14 also opens into the fume cupboard.

Is located between the burner shaft 5 and the distribution channel 14 there is an upward opening between the wall sections 15a and 15b of the burner shaft 5. In this opening is a H-shaped insert 20 used, two parallel each Flanges the insert after the two wall sections 15a and 15b Grasp kind of a groove, so that the insert by plugging and Moving can be assembled. The insert 20 serves as a throttle shaft and has an upwardly closed cavity 22 on. The insert 20 projects down over the lower neck of the Channels 12a to 12c and forms together with the wall sections 15a and 15b and the bottom of the opening between them Wall sections a passage 25 and thus a flow restriction for the gas flow coming from the burner shaft. How from 1, the distribution channel 14 extends in a lower area under the side channels 12a, 12b and 12c, see above that a deflection section with a larger cross section than that of the passage 25 is formed. By moving the insert 20 can the cross section of the passage 25, which the Transition from the burner shaft 5 to the heat exchanger section 10 forms, are set so that particularly favorable flow conditions and an optimal heat transfer can be guaranteed. This cross-section is used for operation by fixing the insert 20 kept constant.

The combustion chamber of the gas burner preferably goes directly into the overheating protection tube 7, which e.g. are made of steel can. The overheating protection tube 7 conducts the exhaust gases of the burner to a level below the water level in the steam generator 1 and preferably up to approximately the level of the approach of the channels 12a to 12c. In this way it is avoided that the hot exhaust gases of the burner with a non-cooled wall section of the burner shaft 5 come in contact above the water level and there cause overheating. Typically the overheat protection tube Part of the burner's combustion chamber.

The exiting from the overheating protection tube 7 Brenners are diverted by 180 ° to the channels 12a, 12b, 12c and 14 and pass through the passage 25 of the connecting portion into the heat exchanger section 10. Because of the lesser Cross section of the passage 25, the gas flow receives a stronger Pulse component transverse to the original flow direction what leads to the fact that the radially outer flow channel 12a receives a sufficient proportion of the gas flow. The Exhaust gases then flow - in the opposite direction as in the burner shaft 5 - in channels 12a, 12b, 12c and 14 to the trigger and give off heat to the liquid in the steam boiler 1.

In the embodiment of FIGS. 3 and 4 Invention has the insert 20 additional pipe sections 30 and 32 on which the distribution channel 14 with the inner cavity 22nd connect the insert 20. The interior of the insert 20 forms thus an uncooled bypass section for part of the hot Exhaust gases that come from the burner shaft 5 and feed them hot Exhaust gases at locations of channels 12a to 12c where those Exhaust gases that have not been routed via insert 20 have already cooled down. This is a leveling out the heat transfer in the axial direction. Because the hot exhaust gases are under a higher pressure in the area of the passage 25, than the already cooled exhaust gases in the channels 12a to 12c at the level of the pipe connections 30 and 32, arises in the area of the passage 25 a suction into the shaft 22, the bypass flow through this shaft.

The embodiment of the invention shown in FIGS. 5 and 6 essentially corresponds to the embodiment according to FIG. 3 and 4. However, here are two symmetrically arranged and the same constructed heat exchanger sections 110a and 110b are provided, which heat exchanger channels 112a to 112c and 112e to 112f, respectively and have distribution channels 114a and 114b. Every heat exchanger section is associated with a hollow insert 120a or 120b, which in the Area of the connecting section with the combustion chamber 3 a Passage 125a and 125b limited and pipes 130a and 130a and 132b and 132b with which hot exhaust gases are passed to a higher one In place of the distribution shafts 114a and 114b can. The construction corresponds essentially to that the embodiment of Figures 3 and 4; on a detailed A description of the individual elements is therefore omitted. Of course can about the two shown in Fig. 5 and Fig. 6 Heat exchanger sections also other heat exchanger sections be provided along for example an axis perpendicular to the connection axis between the heat exchanger sections 110a and 110b can be arranged. Others too, for example ring or polygonal arrangements of Heat exchanger sections are possible. Likewise, several can 1 with each other or with heat exchangers 3 can be combined.

The embodiment of the invention shown in FIGS. 7 and 8 essentially corresponds to the embodiment according to FIG. 3 and 4. Here, however, is the one surrounding the overheating protection tube 7 upper end of the burner shaft 5 closed at the top, so that between the overheating protection tube and the insert 20th a further flow channel 38 is formed. The insert 20 extends not to the top of the burner shaft, but ends at a certain distance from it, being inner cavity 22 is closed at the top. Above the Insert 20 is another between the wall sections 15a and 15b, downwardly closed insert 40 arranged, wherein between the lower end of the insert 40 and the upper end of the Insert 20 a passage 42 remains free. This passage serves in same as the pipes 30 and 32 of the transfer of hot exhaust gases in an upper area of the distribution channel 14 or the channels 12a to 12c, in which exhaust gases that are not the way over have taken the channel 38, already by heat exchange with the Liquid in the steam boiler has already cooled down.

The in the preceding description, the claims and the Drawing disclosed features of the invention can be both individually as well as in any combination for realizing the invention be essential in their various embodiments.

Reference list

1

Steam boiler

3rd

Steam outlet

5

Burner shaft

7

Overheating protection tube

10th

Heat exchanger section

12a, 12b, 12c

Channels of the heat exchanger section

14

Distribution channel

15a, 15b

Wall section of the burner shaft

20th

commitment

22

Cavity in use

25th

Passage

30th

Pipe section

32

Pipe section

38

Transfer channel

40

commitment

42

Passage

110a, 110b

Heat exchanger section

112a-112f

Channels of heat exchanger sections

114a, 114b

Distribution channels

120a, 120b

Calls

125a, 125b

Culverts

130a, 130b

Pipe section

132a, 132b

Pipe section

Claims (10)

Steam generator, in particular for use in kitchen technology, which has a steam boiler (1), a burner shaft (5) for supplying hot exhaust gases from a burner and at least one heat exchanger section (10) with one or more channels (12a, 12b, 12c) for the passage of the Exhaust gases from the burner and for heat exchange with the liquid contained in the steam boiler (1), the channel or channels (12a, 12b, 12c) of the heat exchanger section (10) on the one hand with a fume cupboard and on the other hand via a connecting section with the burner shaft (25) are connected and arranged so that the direction of flow of the gases flowing from the burner to the flue in the channel or channels (12a, 12b, 12c) is different from the direction of flow in the burner shaft (5), characterized in that the connecting section has a passage (25), which is formed by an opening in a wall (15a, 15b) of the burner shaft (5) and an insert (20) ei the opening connects the burner shaft with one or more channels (12a, 12b, 12c) of the heat exchanger section (10) and is partially closed by the insert (20). Steam generator according to claim 1, characterized in that the opening in a side wall has an opening on the entry side of the gases coming from the burner into the burner shaft (5) and the insert (20) with the wall of the burner shaft (5) in the manner of a groove / Spring connection is connected. Steam generator according to claim 1 or 2, characterized in that the insert (20) has in its interior a cavity (22) with an opening which opens into the passage (25). Steam generator according to 3, characterized in that the cavity has at least one further opening (30, 32) which connects to one or more channels (12a, 12b, 12c) of the heat exchanger section (10) at a location downstream of the passage (25) is, so that part of the flow path in the channel or channels (12a, 12b, 12c) is bridged. Steam generator according to one of Claims 1 to 4, characterized in that the heat exchanger section (10) has a distributor duct (14) which adjoins the passage (25) downstream and from which a plurality of side ducts (12a, 12b, 12c) branch off. Steam generator according to claim 5, characterized by a deflection device arranged between the passage (25) and the side channels (12a, 12b, 12c) for deflecting the exhaust gases coming from the passage (25) in the longitudinal direction of the side channels (12a, 12b, 12c). Steam generator according to one of Claims 1 to 6, characterized in that it has a plurality of heat exchanger sections (110a, 110b), the flow systems for the exhaust gases of the burner in each case via a passage (125a, 125b) in a wall of the burner shaft with the burner shaft (5 ) connected is. Steam generator according to one of claims 1 to 7, characterized by an overheating protection tube (7) in the burner shaft (5) for introducing the exhaust gases of the burner into the burner shaft (5) below the level of the liquid level in the steam boiler (1). Steam generator according to claim 8, characterized in that the opening of the overheating protection tube (7) is just above the level of the passage or passages (25; 125a, 125b) which connects the burner (5) with the flow system of the or the heat exchanger sections (10; 110a, 110b). Steam generator according to claim 8 or 9, characterized in that a transfer duct (38) is formed between the walls of the burner shaft (5) and the overheating protection tube (7) and the insert (20, 40) has a second passage opening into the transfer duct (38) (42) which connects one or more channels (12a, 12b, 12c, 14) of a heat exchanger section to the transfer channel (38) at a location downstream of the first passage (25) so that part of the flow path from the first passage (25) is bridged to the discharge through the channels (12a, 12b, 12c, 14), the first passage (25) being formed outside the transfer channel (38).

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