Tumble dryer with automatic fire extinguishing system

Abstract

A tumble dryer, in particular a household tumble dryer, includes a housing, a drum intended for laundry to be dried, which is supported rotatably in the housing, and a container positioned on an outer face of the lateral surface of the drum and holding an extinguishing agent. The container has a first temperature-activated release facility which automatically releases the extinguishing agent into a space outside the drum, in the presence of a temperature produced by a fire.

Claims

1. A tumble dryer, comprising a housing; a drum intended for laundry to be dried, said drum being supported rotatably in the housing and having a drum casing, and at least one container positioned on a lateral outer face of the drum casing and holding an extinguishing agent, said at least one container having a temperature-activated first release facility which automatically releases the extinguishing agent into a space outside the drum in the presence of a temperature produced by a fire.

2. The tumble dryer of claim 1, constructed in the form of a household tumble dryer.

3. The tumble dryer of claim 1, further comprising a further said container positioned on the outer face of the drum casing, said containers being arranged at an angular distance of 180 from one another.

4. The tumble dryer of claim 1, further comprising at least three of said container positioned on the outer face of the drum casing, said containers being arranged at a same angular distance from one another.

5. The tumble dryer of claim 1, wherein the first release facility is made of polypropylene.

6. The tumble dryer of claim 1, wherein the at least one container has a closable filler opening.

7. The tumble dryer of claim 1, wherein the at least one container has an overall volume of maximum around 3 to 4 liters.

8. The tumble dryer of claim 1, wherein the space is between the drum and the housing.

9. The tumble dryer of claim 1, wherein the at least one container projects into an interior of the drum.

10. The tumble dryer of claim 9, wherein the at least one container has an inner part that projects into the interior of the drum, said inner part being embodied as a laundry agitator.

11. The tumble dryer of claim 9, wherein the at least one container has a temperature activated second release facility, which releases the extinguishing agent automatically into the interior of the drum at a temperature produced by a fire.

12. The tumble dryer of claim 11, wherein at least one of the first and second release facilities is made of a plastic, which melts when a fire starts or has started in the tumble dryer.

13. The tumble dryer of claim 11, wherein, wherein at least one of the first and second release facilities is made of a thin-walled plastic, which melts when a fire starts or has started in the tumble dryer.

14. The tumble dryer of claim 11, wherein at least one of the first and second release facilities extends over substantially an entire axial length of the drum.

15. The tumble dryer of claim 14, wherein the at least one of the first and second release facilities is configured to form a plurality of openings that are distributed substantially over the entire axial length of the drum.

16. A tumble dryer, comprising a housing; a drum configured to hold laundry to be dried, said drum being supported rotatably in the housing and having a drum casing, and at least one container positioned on the drum and containing an extinguishing agent, said at least one container having a temperature-activated first release facility which automatically releases the extinguishing agent into an interior of the drum in the presence of a temperature produced by a fire, wherein the at least one container has a temperature activated second release facility, which releases the extinguishing agent automatically into an area between the drum and the housing at a temperature produced by a fire.

17. The tumble dryer of claim 16, constructed in the form of a household tumble dryer.

18. The tumble dryer of claim 16, wherein said at least one container includes at least three containers positioned on the drum, said containers being arranged at a same angular distance from one another.

19. The tumble dryer of claim 16, wherein the at least one container projects into an interior of the drum.

20. The tumble dryer of claim 19, wherein the at least one container has an inner part that projects into the interior of the drum, said inner part being embodied as a laundry agitator.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, features and particularities of the invention will emerge from the description which follows of advantageous embodiments with reference to the figures in the accompanying drawing, in which:

(2) FIG. 1 shows a schematic diagram of a cross section through a first embodiment of a tumble dryer perpendicular to the rotation axis of the drum;

(3) FIG. 2 shows a schematic diagram of a cross section through the drum of the tumble dryer from FIG. 1 parallel to the rotation axis of the drum, said drum being provided with a container;

(4) FIG. 3 shows a schematic diagram of a cross section through a second embodiment of a tumble dryer perpendicular to the rotation axis of the drum; and

(5) FIG. 4 shows a schematic diagram of a cross section through the drum of the tumble dryer from FIG. 3 parallel to the rotation axis of the drum, said drum being provided with a container.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION

(6) FIG. 1 shows a schematic diagram of a first embodiment of the tumble dryer 10. Present in a housing 11, which is delimited at the bottom by a base plate 12 and at the top by a worktop 14, is a drum 20, into which the laundry to be dried is introduced. The tumble dryer 10 and the drum 20 present therein are shown in a rear view, in which the rear wall 29 of the drum 20 can be seen, having a large number of small openings 28 for the passage of air. The drum 20 can be rotated about a rotation axis D running perpendicular to the plane of the drawing according to FIG. 1, as shown by an arrow A.

(7) Positioned on the outer face 24 of the drum casing 22 in this embodiment at an angular distance of 90 are four containers 30 containing an extinguishing agent 9. Each container 30 has a temperature-activated release facility 60, which is embodied so that after being activated at a certain temperature, as produced in a fire, it releases the extinguishing agent 9 automatically into a space 13 within the housing 11 and outside the drum 20.

(8) Details of the first release facility 60 are shown in FIG. 2, which shows an enlarged diagram of a drum 20 with a container 30 positioned thereon. As described above, each container 30 is fastened to or positioned on the outer face 24 of the drum casing 22. Provided on the face 31 of the container 30 facing away from the drum 20 is the first release facility 60, which is configured as a plurality of thin-walled plastic regions 63, which are incorporated in the manner of windows in the face 31 of the container 30 facing away. The plastic regions 63 are preferably formed from polypropylene. The material of the plastic regions 63 and their thickness are selected so that they melt at a certain temperature of for example above 150 C., preferably around 200 C. to 450 C. Such temperatures are reached easily when a fire starts in the tumble dryer 10, as this can result in temperatures of 500 C. to 800 C. As soon as the plastic regions 63 or at least some of them have melted, a number of openings 64 are formed by the melting process, through which the extinguishing agent 9 can flow out, as shown by the arrow B.

(9) As soon as a fire starts in the tumble dryer 10 therefore, the extinguishing agent 9 is released automatically by the first release facility 60 into the space 13 within the housing 11 of the tumble dryer 20 outside the drum 20. As a power supply is not required to activate the temperature-activated release facility 60, with said process simply being brought about by the plastic regions 63 melting due to the temperatures reached to form the openings 64, this fire extinguishing system operates in a very reliable manner without maintenance.

(10) The containers 30 can be formed from metal but can also be made of plastic, which should then have a greater wall thickness and/or a higher melting temperature.

(11) As shown in FIG. 2, the plastic regions 63 of the release facility 60 are distributed over almost the entire axial length of the drum 20. This has the advantage that the extinguishing agent 9 can be distributed in a very regular manner into the interior 13 of the housing 11 of the tumble dryer 10, in particular if the drum 20 is still rotating. If a very large number of roughly point-like small openings 64 are formed when the release facility 60 is activated, the extinguishing agent can be released in the manner of a spray and thus atomized, thereby enhancing fire control efficiency further.

(12) FIGS. 3 and 4 show a second advantageous embodiment of the tumble dryer 10. The features explained in relation to FIGS. 1 and 2 also apply to the other embodiments, without this being repeated in detail. Therefore only the additional particularities of the further embodiments are described below in order to avoid unnecessary repetition.

(13) While four containers 30 are provided in the first embodiment, only three containers 30 are provided in the second embodiment, being positioned so that they are distributed at an angle of 120 over the circumference of the drum 20 on the outer face 24 of the drum casing 22. Each of the containers 30 has an inner part 32, which projects into the interior 26 of the drum 20. This inner part 32 can be embodied here as a cuboidal container, which therefore has a right-angled cross section, but the inner part 32 can also have other cross sections, for example triangular or rounded cross sections. As with the first embodiment the container 30 has a release facility 60 on its face 31 facing away from the drum 20. The inner part 32 also has a further, second release facility 62 on its inner face 33 facing the rotation axis D of the drum 20. The second release facility 62 is preferably embodied in a similar or identical manner to the first release facility 60 but it opens into the interior 26 of the drum 20.

(14) A major advantage of this embodiment is that the combination of the two release facilities 60 and 62 allows very targeted release of the extinguishing agent 9. Depending on whether a fire starts within or outside the drum 20, the temperature rises significantly either in the drum 20 or in the space 13 within the housing 11, while the temperature in the respectively other space rises but much less significantly. As a result therefore the release facility 60, 62, which senses a higher temperature, is always activated, as it is closer to the fire than the respectively other release facility. All the available extinguishing agent is therefore deployed precisely where it is required and no extinguishing agent is released at points where no fire has started. This enhances the efficiency of the fire extinguishing system, as generally only quite a small quantity of extinguishing agent has to be held in reserve, usually between three and four liters.

(15) It may be advantageous, if the inner part 32 of the container 30 projecting into the interior 26 of the drum 20 is also embodied at the same time as a laundry agitator, so that said element has a double function and therefore takes up as little space as possible.

(16) As shown in FIG. 4, the container 30 has a filler opening 34, which can be closed off by means of a cover 36. With this arrangement a user can check at any time whether there is sufficient extinguishing agent 9 in the containers 30 and top up the extinguishing agent 9 as required.

(17) With the abovementioned embodiments the release facilities 60, 62 are only shown on the face of the container 30 facing away from the drum 20 or facing the rotation axis D. It is of course also possible to provide release facilities instead of or in addition to these on the respective end faces or narrow faces.

(18) It is therefore possible without a connection to an electrical power supply for the release facility, in a technically simple, economical and reliable manner, to release the extinguishing agent automatically, thereby ensuring the extinguishing process for the occurring fire, when a limit value of ambient temperature is reached or exceeded.

(19) The invention described above is of course not restricted to the two embodiments described in detail. The different variants of the fire extinguishing system can be used both in condensation dryers and in exhaust air dryers and in each instance ensure that any fire that occurs is extinguished reliably and automatically without requiring any external influence. As it is not necessary to have a connection to the power network or to provide a battery to operate or prepare the fire extinguishing system for operation, the reliability of the fire extinguishing system is also very high.

(20) It should also be noted that features of the invention described with reference to individual embodiments, for example the configuration and arrangement of the container or the number of containers and of the release facilities, can also be present individually or cumulatively in other embodiments, unless otherwise stated or impossible for technical reasons.