DE1551757A1 - Oil or gas burner - Google Patents

Description

The invention relates to an oil or gas burner, the one with a fan for conveying the combustion air is equipped, which is designed as a cross-flow fan »

The known oil or gas burners of the type in question here have to supply the combustion air Conventional blowers for the common room, e.g. axial blowers, radial blowers or drum rotors. This one Blowers have a flat characteristic curve, the volume of air passed through decreases as the back pressure increases. For this reason, when installing such a burner in a heat exchanger, an adaptation to the

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Carry out pressure ratios of the system in question, in particular by installing suitable throttling devices on Fan inlet adjusted and changed accordingly. However, this can only be done by experienced professionals it also requires relatively complicated handling. In addition, with such arrangements also to take into account that the pressure conditions of the system change from day to day and also within it Days can change through the effects of the outside world, the atmosphere, wind, etc. For example, they are take into account daily fluctuations in the size of the chimney draft. In such cases the The amount of air delivered by the fan of the burner is no longer the same as for the set oil or gas throughput for a good combustion required amount of scent. Such changes in the mixing ratio between fuel and air can thus cause the burner to soot. It is also particularly difficult with the conventional ones Forced draft burners the ignition process. When igniting, the gas volume in the furnace room expands through the Sudden heat development very strong and suddenly off. Because this increase in volume is caused by outflow cannot reduce quickly enough on the flue gas side, an above-average pressure builds up in the furnace chamber which can lead to pulsations of the burner or even to the flame flashing back through the burner.

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The invention has set itself the task of the above Avoid disadvantages to a large extent.

For the above-mentioned purpose, according to the invention, the new burner is provided with a so-called aerodynamically highly stable cross-flow fan with a steep initial characteristic and a high end peak for conveying the combustion air to the mixing and combustion chamber. The new burner is therefore characterized according to the invention in that the baffle plate of the fan is constantly removed after the inlet from the blade grille of the impeller to transition into a spiral shape 'that the angle between the tangent at the start of the baffle plate or the tangent at the inflection point on the inlet side and the tangent to the leakage area limiting Wandungspartie of the guide plate is substantially smaller than 90 °, and preferably 50 - is 60, the vortex tongue of the fan üaß a ^ s two legs beste.it, which form an angle of about 10 - form 60 ° that the gap between the suction-side leg of the vertebral lungs and the lattice of the rotor zv.va vertebra tapered towards and against the direction of rotation and that flow guide means are assigned to the impeller, which at the formation of at least one return duct tapering from the pressure side to the suction side take part,

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through which part of the air flow emerging from the impeller is returned from the pressure side to the suction side will. Here, the vortex tongue is expediently assigned to the impeller of the blower and to him arranged opposite so that the sucked in air when it hits the L ^ frad in the area of the vertebral tongue is aligned approximately tangentially to the outer circumference of the impeller. The vertebral tongue can be wedge-shaped or sickle-shaped be designed, it can be pivotable and / or displaceable. In such an arrangement, a Change of the back pressure up to a certain size not as with conventional blowers with a strong change in volume connected, so that in this respect no adjustment to the respective conditions must be carried out by professionals. The exact mixing ratio between fuel and air can rather, they can be set by a person skilled in the art during the manufacture of the burner without a subsequent adjustment to the respective pressure conditions in the system in which the burner is used. Now only one helper is required to switch the burner to the various Combustion chambers with a wide variety of pressure conditions can be grown. The high end tip of the Blower characteristic curve - among the conventional blower

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there is nothing comparable that offers an ideal opportunity to detect pulsations during Start-up or even a flashback of the pilot flame to avoid »Apart from these advantages, which are caused by the characteristics of the grebläsekennlinie, a multiple of the static pressure can be achieved with the highly stable cross-flow fan described conventional blower of the same size. One is with it capable of bridging significantly higher combustion chamber resistance than it is today with the same size is possible, and it can also allow itself to reduce the pressure loss in the mixing device of the combustion head increase, which is reflected in the improvement in combustion. The volume of the air flow can be but now no longer change the steep character by adjusting and setting the throttle devices the characteristic would cancel. According to the invention, flow guide means are assigned to the impeller for this case, which participate in the formation of at least one return channel tapering on the pressure side to the suction side, through the .a more or less large part of the Impeller exiting air flow is returned from the pressure side to the suction side. With this arrangement

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the characteristic maintains its steep character, it only shifts in an affine manner. But this one Aerodynamically highly stable cross-flow fan sensitive to built-in components in the close area behind the G-bladder react, as could happen, for example, by inserting the oil nozzle and the ignition electrodes, According to the invention, the burner tube with nozzle assembly and ignition electrode is only arranged behind an air circulation system. The burner tube is preferably axially parallel to the fan wheel. The combustion air is here At right angles via guide plates or spirally guided into the burner tube. By the shape of the in the spiral arranged baffles one can upright a more or less large swirl of the flow in the burner tube get or avoid. This type of deflection causes only minimal flow losses and is guaranteed even speed distribution in the burner tube.

In the drawing, exemplary embodiments of the subject matter of the invention are shown. Show it:

Fig. 1 shows a burner according to the invention in

schematic representation in a side view • in a vertical section,

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FIG. 2 shows the arrangement according to FIG Top view,

3 shows the arrangement according to FIGS. 1 and 2 in a perspective illustration,

4 shows the combustion head of the arrangement according to the invention in a side view in a vertical section on a larger scale,

Fig. 4a, 4b and 4c various details of the burner according to the invention partially in different embodiments each in one Side view in a section on a larger scale,

Fig. 5, 6 and 7 three variants of the in connection with the burner according to the invention to be used blower each in a schematic representation,

8 shows a further detail of the burner according to the invention in a schematic representation and

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9, 10 and 11 three diagrammatic, graphical comparisons of the invention according to the invention Burner with well-known burners.

The burner according to the invention has a housing which consists of a lower housing part 1 and a cover plate consists. These parts can be taken apart and put together. The cover plate carries the drive motor 3 with the pump 4 and the burner head insert 5 as well as all electrical parts such as the solenoid valve 6 etc. The lower part of the housing carries the burner head insert 5 associated burner tube 7 and, together with the cover plate 2, includes the impeller 8 of the fan. The burner head insert which is removably inserted into the cover plate and with this in the manner of a Bayonet lock can be connected, on the one hand carries the burner nozzle 10 with the oil supply line and on the other hand the ignition electrode 12 and the photocell 13 serving for flame monitoring, whereby the Oil supply pipe on the burner head insert in the pipe's longitudinal direction according to arrow a and the baffle plate H on the oil supply pipe is guided back and forth displaceably in the longitudinal direction of the pipe according to arrow b. In addition, there are still those Guide vanes 15 provided, the impeller of the to promote the

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air serving blower are assigned. The burner tube is attached to an annular flange 16, which is coaxial with the burner head insert, on the side of the Geliäuseunterteil facing away from the cover plate in the area of the guide vanes 15, which is bent outwards from the housing lower part so that the transition between the inner surfaces of the housing lower part B and the Brennkopfeinsatres is well rounded like a run-in, as shown in IS. The parts of the wall parts of the lower housing part facing the impeller and the cover plate opposite the end faces of the impeller of the fan are withdrawn from the other parts of the corresponding wall parts in the sense of "away from the impeller ¹¹ , as shown at> 2o, 21, and between the front edges of the part of the bottom of the impeller assigned to the blades and the corresponding parts of the housing wall, a labyrinth-like seal is provided. This labyrinth-like seal is particularly important for fan impellers whose length is smaller than the diameter, and is designed as a labyrinth gap between the impeller and the fan in the radial direction is less than 16 and in the axial direction less than 1.5 pounds of the fan diameter. In the arrangement according to Pig

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Annular grooves 25 are provided which are concentric, while "in the arrangement according to FIG. 4c an annular groove 27 in the Housing wall and a ring-like running in this Projection 28 are provided on the bottom 29 of the fan wheel. in both cases the gap is 30 or 31 »between the peripheral edge of the base fn # * 26 or 29 and the opposite one Vandungepartie 26a, 29a of the öehlttaes is correspondingly small.

Overall, there is a housing that is an elongated flat prismatic structure (Fig. 2 and 3), whose both axial ends are designed to be flat cylindrical, as shown at 32, 33. These cylinders, one of which is a dumbbell the fan impeller is formed by the baffle connected by an elongated housing body 34, the outline of which is formed on one long side by the curve enveloping the two semicircles at the axial bands becomes (cf. 35). On the other long side are between

36.37 provided and between 4Φάβη two cylinders 32, 33 constrictions / there is a bent tongue 38 which releases the inlet for the conveying air.

In the arrangement according to the invention, the burner tube is with the nozzle holder and. the ignition electrodes are only arranged behind an air deflector. Preferably here stands the burner tube axially parallel to the fan wheel. Me combustion air is at right angles over baffles or

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BATHROOM OFMGINAL

spirally guided into the burner tube. Due to the shape of the baffles arranged in the spiral, one can in the Burner tube a more or less large swirl of the Maintain or report flow. This type of redirection causes only low flow losses and guarantees even speed distribution in the burner tube.

Is it still noteworthy in the subject of the discovery, dafi the Oehiuseunjfctrttil with an arbitrarily high spiral can be trained * (depending on the maximum breath «) and that the mounting plate is provided with all the equipment, whereby in a very simple way (sucked up Tongue 36) «a precisely ideal air flow is achieved. The burner head insert can be pulled out, see B. by means of Bayonet lock. Bs is a very course, but a long burner tube is also possible. The file can be used with the Removable cover cap 4o to be covered.

The lower housing part can otherwise by casting or Syringes are manufactured that can guide vanes are also poured here. The cover plate can be processed in a very simple way. The flange 16 is used for attachment to the boiler wall 4o.

The cross-flow fan of the burner according to the invention

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has an impeller 50, a flow-guiding baffle 51 and a vortex tongue 52 separating the incoming and outgoing flow. After the inlet 53, the baffle constantly moves away from the blade grille of the impeller in order to merge into a spiral shape. According to the invention, the angle C ″ between the tangent 54 at the start of the guide plate or at the inflection point on the inlet side and the tangent 55 on the wall portion of the guide plate delimiting the exit area is substantially smaller than 90 ° and is preferably 30 ° to 60 °. The vertebral tongue 52 has swel legs 52a , 52b, which together form an angle of about 10 ° to 60 °. Finally, the arrangement is also made in such a way that the gap between the suction-side leg 52b of the vortex tongue and the blade grating of the rotor tapers towards the vortex and counter to the direction of flow The arrangement is such that the central angle ^ between the diameter d ^, which passes through the inflection point or the start of the guide plate, and the diameter d ₂ , which is passed through the point on the impeller circumference closest to the vortex tongue, is less than 180 ° The central angle! * - measured in the circumferential direction or opposite to this - z between the diameter d and the diameter d, which passes through the tip of the vertebral tongue, is between 5 ° and 60 °. It can be seen that the inventive

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The arrangement is made so that it is in the area of the vertebral tongue Air hitting the impeller approximately tangentially is directed towards the impeller circumference. This is due to the arrangement of the vortex tongue opposite the impeller and its assignment attributed to this with. The effect according to the invention also contributes to the fact that the area of the vertebral tongue that is closest to your impeller is a very small section of the impeller circumference to the outside,

According to the invention, the impeller is also assigned flow guide means, which participate in the formation of at least one exhaust duct tapering, for example, from the pressure side to the suction side, through which part of the air flow emerging from the impeller is returned from the pressure side to the suction side. In the embodiment according to FIG. 5, the return channel is formed by a small guide plate 56 which runs at a distance from the vertebral tongue. Be then forms the ^{flow seized in I 1} Ig * 5. Also, several Rülikführungskanäle gem. Fig. 7 is formed vacden, for which purpose one more consecutive guide plates 57a, 57b 57c provides for _t, which together form a wedge shape and form the return channels with the swirl tab 58. In all these cases, the return flow channel can taper from the pressure side to the suction side. A slide can be provided at the inlet opening of the return card. The baffles

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can gea fig. 7 with its impeller-side brew this can be pivoted to and away from this. The vortex itself can also act as a flow guide be designed in that it consists of a hollow body, the walls of which have holes on the side and on the pressure side, Slots or similar openings for the passage of the Medium. The vertebral tongue can, as in fig. 5 be 52 and in Pig. 7 at 58 have the shape of an ia cross-section triangular wedge, e.g. 5 shows, inter alia, an ion «« which is parallel to the axis of rotation of the fan. The vertebral tongue can, however also, like at 59 in Jig. 6 is shown, a sickle-shaped Gfitalt have and i.B. the circumference of the impeller remaining displaceable along parallel eu itself it can possibly also be slidable and swivelable be.

According to Pig. 8 ait a pointer 6o be connected, which can be pivoted along a scale 61, so that the air throughput can adjust precisely. 3is to some counter pressure the conveyed air volume τβ $ remains independent of this. System pressure fluctuations have no effect at the set volume delivered. Differences in altitude, e.g. whether the Brenner is on the lake or in the high mountains is operated, which is noticeable in the air density

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bar, can be adjusted, just as extreme Combustion chamber pressure :.

9 shows the characteristic curve of a highly stable one at 7o Fan unc at 71 the characteristic of a conventional one Blower. 'The highly stable blower is marked due to a minimal change in volume with a change in pressure, the operating point can be at significantly higher pressure> and the same volume (better combustion). In Pig. Io is closed recognize that with a normal fan with characteristic curve 72 the pressure in ckr combustion chamber during the ignition process be a multiple of the working pressure on the short side can and exceed the maximum pressure that can be built up by the blower 00 that the flame flashes back, which is not the case with a highly stable fan. Flg. 11 shows this with the highly stable cross-flow fan according to Invention by adjusting a characteristic curve shift is achieved, which results in a large and proportional control range, even with the lowest Position, a child volume is always promoted. at conventional blowers result from, the irosulungscrgan high pressure losses, an exact setting is hardly possible because it is too weak at the beginning and too strongly addressed later so that the control range is designated as small be aiui. The highly stable cross-flow fan takes the

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Required amount of air linearly with the wheel width, so that the maximum volume for a given wheel diameter the rotor width can be determined. With the known blowers, on the other hand, the delivery volume can be passed through Cannot increase the fan width.

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Claims (32)

Expectations [1 J oil or gas burner, which is equipped with a fan for conveying the combustion air, the is designed as a cross-flow fan, characterized in that the guide plate of the fan is after Inlet from the blade grille of the impeller steadily removed to merge into a spiral shape that the angle between the tangent at the start of the baffle or the tangent at the inflection point on the inlet side and the tangent to the The wall part of the guide plate delimiting the exit area is significantly smaller than 90 ° and preferably 30-60 ° is that the vortex tongue of the fan consists of two legs that form an angle of about 10 - 60 ° that the gap between the suction-side leg of the vortex tongue and the blade grille is formed the rotor tapers towards the vortex and counter to the vertical direction and that the impeller flow guide means which is associated with the formation of at least one, e.g. from the pressure side to the suction side take part in the tapering return channel through which a part 009820/0561 ORIGINAL INSPECTED of the air flow γοη emerging from the impeller the pressure side is returned to the suction side. 2. Oil-vein gas burner according to claim 1, characterized in that that the vortex tongue is assigned to the impeller of the fan and so arranged opposite it is that 'the air sucked in when it hits the The impeller is aligned approximately tangentially to the outer circumference of the impeller in the area of the V / vortex tongue. 3. Oil or gas burner according to claim 1 or 2, characterized in that the vortex tongue is the The impeller of the fan is assigned and arranged opposite this so that the impeller opposite Part that covers the smallest possible circumferential extension of the impeller towards the outside. 4 · oil or gas burner according to one of claims 1 to 3 » characterized in that the return channel tapers from the pressure side to the suction side. 5 »Oil or gas burner according to one of claims 1 to 4» characterized in that the return channel is held at a distance from the vertebral tongue 009820/0561 _{0RIGINAL1NSPECTED} small baffle and a part of the vertebral tongue facing away from the pressure side is formed. 6. oil or gas burner according to claim 5 »characterized in that that as flow guide means several one behind the other, forming a wedge baffles are provided together with the vertebral tongue form several return channels. 7 oil or gas burner according to claim 5 or 6, characterized in that the guide plates with their impeller-side end towards this and away from it are pivotable. 8. Oil or gas burner according to one of claims 1 to 7 _t, characterized in that a slide-like adjusting member is provided on the inlet side of the Rüokführnngskanals, through the adjustment of which the passage cross-section of the return channel can be changed. 9 oil or gas burner according to one of claims 1 to 4, characterized in that the vortex tongue itself is designed as a flow guide means by being made from 00 9820/0561 consists of a hollow body, the walls of which on the suction side and have holes, slots or similar openings on the pressure side for the medium to pass through. 10. oil or gas burner according to one of claims 1 to 9, characterized in that the vertebral tongue has the shape of a triangular wedge in cross section. 11. oil or gas burner according to one of claims 1 to 9 » characterized in that the vertebral tongue has sickle-shaped Gesfe.lt. 12. Oil or gas burner according to claim 10 or 11, characterized in that the vortex tongue around a is pivotable to the axis of rotation of the fan parallel axis. 13. Oil or gas burner according to claim 10 or 11, characterized in that the vortex tongue on the circumference of the impeller remaining parallel to itself. 14. oil or i-as burner according to claim * Q or 11, characterized in that the Wtr ^ e'l.st>: ige around a ζυτ OvSSIC / ύο £ 1 BATH ORIGINAL Γ / Ο / Axis of rotation of the fan can be pivoted parallel axis and along the circumference of the impeller parallel to itself itself is relocatable. 15 · Oil or gas burner according to one of Claims 1 to 14j, characterized in that the one for the suction side of the fan directed towards the central angle between the point of inflection on the inlet side or the Baffle start running diameter and the Diameter that is passed through the point on the circumference of the impeller that is closest to the vortex tongue, is less than 180 °. 16. Oil or gas burner according to one of claims 1 to 1-5, characterized in that the in the direction of rotation or oppositely measured central angle between the diameter that begins through the guide plate or the inflection point on the inlet side and the diameter passing through the tip of the vertebral tongue passes through, is between 5 and 60 °. 17 oil or gas burner according to one of claims 1 to 16, characterized in that the housing consists of two parts which can be detached and plugged together, namely 009820/0561 a lower housing part and a cover plate, which the drive motor with the pump, the Carries the burner head insert and all electrical parts, while the lower part of the housing sows the burner head ζ associated burner tube carries, and that in the interior of the housing between the cover plate and the lower housing part the fan wheel is included. 18. Oil or gas burner according to claim 17, characterized in that that the burner head insert inserted into the cover plate so that it can be pulled out, on the one hand, the burner nozzle with the oil supply line and, on the other hand, the ignition electrode and the photocell used to control the flame contains. 19. oil or gas burner according to claim 17 or 18, characterized in that the axis of rotation of the impeller of the fan and the longitudinal center axis of the Burner head insert run parallel to each other. 20. Oil or gas burner according to one of the claims 17 to 19 »characterized in that the lower housing part is made by casting, with the air guide system being cast. 009820/0561 ORIGINAL 21. Oil or gas burner according to one of the claims 17 to 20, characterized in that the oil supply pipe on the combustion head insert back and forth in the pipe's longitudinal direction is displaceably guided. 22. Oil or gas burner according to one of claims 17 to 21, characterized in that the baffle plate on the oil supply pipe is displaceable back and forth in the pipe's longitudinal direction is led. 23. oil or gas burner according to one of the claims 17 to 22, characterized in that the burner tube is attached to an annular flange coaxial with the burner head insert centered on the side of the housing "lower part" facing away from the cover plate in the area of the guide vanes and is attached, which is bent from the lower housing part to awssen that the transition between the inner surfaces the lower part of the housing and the burner head insert is well rounded like a run-in. 24. Oil-vein gas burner according to one of claims 17 to 23, characterized in that the parts opposite the end faces of the impeller of the fan the wall parts of the lower housing part facing the impeller un the cover plate compared to the rest 009820/0561 Parts of the corresponding wall parts in the sense of "away from the rotor" step back, so that the rotor is contained, so to speak, between two opposing depressions in the G-ehäusewandung, and that between the part of the bottom of the impeller assigned to the front edges of the blades and the corresponding part Parts of the housing wall have a labyrinth-like sealing arrangement, expediently in the form of a so-called Labyrinth gap is provided. 25. oil or gas burner according to claim 24, which is preferably equipped with a fan impeller, the Length is smaller than its diameter, characterized in that the TTmfangkante the bottom of the impeller runs at only a small distance from the facing surface of the housing wall and the front edges of the Several parts of the housing wall opposite the impeller, e.g. three concentric, closely spaced parts Annular grooves have approximately the same depth. 26 oil or gas burner which is preferably equipped with a fan impeller according to claim 24 'whose length is less than j.st 3An diameter in _t aadurch "AEAI? dl? "Tmfangskante de? -Vxiiv.-ie of the barrel he ~ BATH ORIGINAL wheel runs at only a small distance from the facing surface of the housing wall and the parts of the housing wall opposite the front edges of the impeller have at least one narrow annular groove in which an annular projection runs around the facing side of the bottom of the impeller « 27. Oil or gas burner according to claim 25 or 26, characterized in that the thickness of the labyrinth gap in the radial direction is less than 1 ° / ° and in the axial direction less than 1.5 ° / ° of the fan diameter 28. Oil or gas burner according to one of claims 17 to 27j, characterized in that the lower housing part on the TTnterseite has a flat wall part and on the circumference along a side end wall approximately at right angles to the flat wall part on the underside has ₉ whose area opposite the fan inlet is bent up like a tongue is. 29 »Oil or gas burner according to claim 28 _s, characterized in that the outline of the lower housing part 009820 / DSi corresponds to an elongated structure which has one inwardly open at each of its two axial ends Semicircle and its "both semicircles on one Long sides are connected to each other by an envelope curve, while on the opposite long side between the two semicircles there are two constrictions and a tongue that is bent upwards is provided between them is. 30. Oil or gas burner according to one of claims 17 to 29, characterized in that the housing is the Has the shape of an elongated structure with a flat prismatic shape. 31. Oil or gas burner according to claim 30, characterized in that that the axial end portions of the elongated structure representing the housing each have a flat cylindrical shape, one of which is a cylinder jacket is formed by the guide plate assigned to the fan wheel and has longitudinal axes parallel to one another, and are connected by an elongated flat prismatic housing body on one longitudinal side has an opening serving as an air inlet and, moreover, the one assigned to and between the fan wheel and the combustion head arranged vortex tongue as well as the air 009820/0561 _o ORIGINAL INSPECTED contains guiding elements. 32. oil or gas burner according to one of claims 17 to 31, characterized in that the on the housing rotatably mounted vertebral tongue with a pointer mounted pivotably on the top of the housing is connected, which is adjustable back and forth along a scale. 33 »Oil or gas burner according to claim 32, characterized in that the scale assigned to the pointer for adjustment to the height and / or the counter pressure can be pivoted along a corresponding further scale is. 34 · Oil or gas burner according to one of Claims 17 to 33, characterized in that on the cover plate a housing cap can be pulled up, which is used to cover the elements seated on the cover plate such as pump, motor, etc. is used. 35 · Oil or gas burner according to one of Claims 17 to 34, characterized in that the burner head seen in the air flow direction only behind the means is arranged to deflect the air. 00 9820/0561 ORIGINAL IMSPEGTED 3g Blank page ORIGINAL INSPECTED