Filter device and method for dedusting same

Abstract

A filter device for a vacuum cleaner having a turbine device and a motor. The vacuum cleaner includes two chambers and filter elements of the filter device are dedusted by an abrupt change in position of a dividing element in the chambers. Since, when one of the two chambers is being dedusted, the suction operation of the vacuum cleaner can be maintained through the other chamber, the filter dedusting can advantageously take place during continued suction operation of the vacuum cleaner. A method for dedusting a filter device in a vacuum cleaner, wherein, as a result of a valve being actuated, an air volume is driven out of one of the two chambers so that a dividing element is advantageously made to change position, and this can result in a backflushing pulse and mechanical shaking of the filter element, and dedusting of the filter device.

Claims

1-15. (canceled)

16. A filter device for a vacuum cleaner having a turbine device and a motor for generating a first main air stream or a second main air stream through a collecting tank of the vacuum cleaner, the filter device comprising: a first chamber and a second chamber, each with a filter element, an inflow opening and a turbine opening, wherein a valve is designed to close either the inflow opening or the turbine opening, wherein a negative pressure prevails in the chamber when the inflow opening is closed and wherein atmospheric pressure prevails in the chamber when the inflow opening is open, the first and second chambers also each including a divider having a parked position and a dedusting position, a switchover between the parked position and the dedusting position taking place by letting in atmospheric pressure by actuating the valve, the dividers being designed to apply a pulse to the respective filter element when the dedusting position is taken up so that the filter element is dedusted.

17. The filter device as recited in claim 16 wherein a negative pressure prevails in the collecting tank and in at least one of the first and second chambers during operation of the vacuum cleaner.

18. The filter device as recited in claim 16 wherein the switchover between the parked position and the dedusting position of the dividing elements takes place via a pleat.

19. The filter device as recited in claim 16 wherein the turbine openings are designed to allow a flow connection between the chambers and the turbine device.

20. The filter device as recited in claim 16 wherein the chambers have inlet openings and wherein the filter elements are designed to close the inlet openings such that dust particles are filtered out of the first and second main air streams.

21. The filter device as recited in claim 16 wherein the dividers each have a membrane plate.

22. The filter device as recited in claim 21 wherein the dividers also have elastomer valves designed to prevent an air flow through the membrane plate in that the elastomer valves bear in an airtight manner against the membrane plate, or wherein the elastomer valve are designed to form, with the membrane plate, a gap through which an air flow can flow.

23. The filter device as recited in claim 22 wherein the gap between the elastomer valve and membrane plate is formed in that the elastomer valve is fastened to the membrane plate on one side and can be present at a spacing from the membrane plate on the other side of the membrane plate.

24. The filter device as recited in claim 16 wherein a front space is formed in each of the first and second chambers between the filter element and the divider and a rear space includes the outflow opening and the turbine opening.

25. The filter device as recited in claim 16 wherein ventilation channels are provided between the collecting tank and a vacuum cleaner head.

26. A method for dedusting a filter device in a vacuum cleaner, the method comprising the following steps: a) providing the filter device as recited in claim 16; b) operating the vacuum cleaner, wherein, during operation of the vacuum cleaner, a negative pressure prevails in a collecting tank of the vacuum cleaner and in at least the first chamber or the second chamber; c) generating atmospheric pressure in one of the first and second chambers by actuating the respective valve, wherein, as a result of the valve being actuated, the turbine opening of the one chamber is closed and an inflow opening of the one chamber is opened and furthermore the divider within the chamber is made to change position from the parked position into the dedusting position; and d) dedusting the filter element by the change in position of the divider.

27. The method as recited in claim 26 wherein when the vacuum cleaner is in operation, a first main air stream or second main air stream is generated, the first or second main air stream forming between a suction hose inlet and the turbine device.

28. The method as recited in claim 26 wherein when the inflow opening is opened, a pressure equalizing stream passes into the first chamber or into the second chamber from a ventilation channel.

29. The method as recited in claim 26 wherein during operation of the vacuum cleaner, there is a flow connection between the first and second chambers and the turbine device, wherein the flow connection is formed by a flow channel portion arranged between the respective turbine opening and the turbine device.

30. The method as recited in claim 26 wherein the filter element of one of the first and second chambers is dedusted upon continued suction operation through the other of the first and second chambers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Further advantages will become apparent from the following description of the figures. Various exemplary embodiments of the present invention are illustrated in the figures. The figures, the description and the claims contain numerous features in combination. A person skilled in the art will expediently also consider the features individually and combine them to produce useful further combinations.

[0046] In the figures, identical and similar components are denoted by the same reference signs.

[0047] In the figures:

[0048] FIG. 1 shows a schematic side view of a vacuum cleaner having a preferred embodiment of the filter device in a vertical arrangement

[0049] FIG. 2 shows a schematic illustration of the vacuum cleaner while both chambers are participating in suction operation

[0050] FIG. 3 shows a schematic illustration of the vacuum cleaner while the filter element of the second chamber is being dedusted

[0051] FIG. 4 shows a schematic illustration of the vacuum cleaner while the filter element of the second chamber is being dedusted

[0052] FIG. 5 shows a schematic illustration of the vacuum cleaner at the end of the dedusting process of the second chamber

[0053] FIG. 6 shows a schematic illustration of the vacuum cleaner while the filter element of the first chamber is being dedusted

[0054] FIG. 7 shows a schematic illustration of the vacuum cleaner while the filter element of the first chamber is being dedusted

[0055] FIG. 8 shows a schematic illustration of the vacuum cleaner at the end of the dedusting process of the first chamber

[0056] FIG. 9 shows possible configurations of the pleat

[0057] FIG. 10 shows a schematic side view of a vacuum cleaner having a preferred embodiment of the filter device in a horizontal arrangement

DETAILED DESCRIPTION

[0058] FIG. 1 shows a side view of a vacuum cleaner 1 having a preferred embodiment of the filter device 2 in a vertical arrangement. Illustrated in a lower region of the vacuum cleaner 1 is the dust collecting tank 5, which has a suction hose inlet 19. A suction hose, which can be connected for example to a floor nozzle, can be attached to this suction hose inlet 19. Through the suction hose, dust particles or drilling dust can be sucked in. The sucked-in dust then passes through the suction hose inlet 19 into the dust collecting tank 5 of the vacuum cleaner 1.

[0059] The upper region of the vacuum cleaner 1 is formed by a vacuum cleaner head 23. Located in the vacuum cleaner head are, for example, the turbine 3 and the motor 22, with which the negative pressure for sucking in the dust particles and drilling dust is generated. Provided between the vacuum cleaner head 23 and the dust collecting tank 5 are ventilation channels 20a and 20b with which air can be sucked in from the environment of the vacuum cleaner 1 through openings in the housing. This air sucked in through the ventilation channels 20, 20b can form for example a pressure equalizing stream when pressure equalization is intended to take place in the vacuum cleaner 1. This can be the case for example when the negative pressure within the vacuum cleaner 1 is intended to be interrupted in order to carry out filter dedusting. It is necessary to dedust the filter elements 7a, 7b for example when the filter elements 7a, 7b of the filter device 2 are clogged with dust. The initially loose dust can solidify to form a filter cake 24 (see, e.g., FIG. 3), which can be detached from the filter elements 7a, 7b only with difficulty. In order to provide effective filter dedusting in which in particular the suction operation of the vacuum cleaner 1 does not need to be interrupted, the invention is presented in the following text:

[0060] Provided between the dust collecting tank 5 and the vacuum cleaner head 23 are two chambers 6a, 6b, the filters 7a, 7b of which can be dedusted alternately according to the invention, while the suction operation of the vacuum cleaner 1 can be continued in the respectively other chamber 6a, 6b. The chambers 6a, 6b are formed in a substantially identical manner, but axisymmetrically to a partition wall 25 separating the two chambers, and so in particular the first chamber 6a is described in the following text. This is the left-hand chamber in FIG. 1. Located in terms of flow in a front region of the chamber 6a is an inlet opening 13a, through which the dust-laden air stream 4a (see, e.g., FIG. 2) is sucked from the dust collecting tank 5 in the direction of the turbine 3. In order to protect the turbine 3 from the dust, a filter element 7a is provided upstream of the inflow opening 13a, said filter element 7a being designed to filter a substantial proportion of the dust out of the air stream 4a. Once the air stream 4a has passed through the inlet opening 13a and the filter element 7a, the air stream 4a passes into a front space 17a (see, e.g., FIG. 3) of the first chamber 6a. The first chamber 6a is divided by a dividing element 11a into the front region 17a and a rear region 18a. The dividing element 11a is configured such that the air stream 4a can flow through the dividing element 11a such that it passes into the rear region 18a of the first chamber 6a. In particular, the dividing element 11a comprises an air- and dust-permeable membrane plate 14a (see, e.g., FIG. 6), which is fastened to the side walls of the first chamber 6a by a respective pleat 12a. The pleats 12a can be present in two states, wherein the pleats 12a are preferably in a parked position during suction operation of the first chamber 6a. The parked position of the pleats 12a or of the membrane plate 14a is in particular characterized in that the membrane plate 14a and the filter element 7a of the first chamber 6a are spaced apart from one another, i.e. that a space is formed between the membrane plate 14a and the filter element 7a, said space being referred to, according to the invention, as the front region 17a of the first chamber 6a.

[0061] In addition to the membrane plate 14a, the dividing element 11a comprises an elastomer valve 15a (see, e.g., FIG. 8). This elastomer valve 15a is open when the first chamber 6a is working in suction operation. In this state of the elastomer valve 15a, the air stream 4a can pass through the dividing element 11 a and the elastomer valve 15a. The air stream 4a flows in particular through a gap 16a (see, e.g., FIG. 4) that is formed between the membrane plate 14a and the elastomer valve 15a.

[0062] The rear space 18a (see, e.g., FIG. 3) of the first chamber 6a has two possible outlets, of which in each case one outlet is open and the other outlet is closed. This interplay is brought about by a valve 10a, which can be moved from a first position into a second position. This actuation takes place preferably by means of a sliding movement of the valve 10a. In other words, the valve 10a can be slid from a first position into a second position. According to the invention, the positions of the valve 10a can also be referred to as the suction operation position and as the filter dedusting position, respectively.

[0063] During suction operation of the first chamber 6a—as depicted for example in FIGS. 2 to 5—the valve 10a is set such that a turbine opening 9a of the first chamber 6a is open. Through the open turbine opening 9a, there is a flow connection between the first chamber 6a and the turbine 3. As a result, a negative pressure prevails in the first chamber 6a, and in the entire dust collecting tank 5 of the vacuum cleaner 1, such that dust can be sucked into the interior of the vacuum cleaner through the suction hose inlet 19. In particular, the air stream 4a can pass through the open turbine opening 9a into the region of the turbine 3. To this end, the air stream 4a can flow through a flow channel portion 21a that is provided between the turbine opening 9a and the turbine 3.

[0064] FIG. 2 shows a schematic illustration of the vacuum cleaner 1 while both chambers 6a, 6b are participating in suction operation. The dark regions in FIGS. 2 to 8 are intended to represent the regions of the vacuum cleaner 1 in which a negative pressure prevails. In the exemplary embodiment of the invention that is illustrated in FIG. 2, both valves 10a, 10b of the vacuum cleaner 1 are in the suction operation position and the dividing elements 11a, 11b of the two chambers 6a, 6b are each in the parked position, such that the air streams 4a and 4b can flow from the dust collecting tank 5 through the filter elements 7a, 7b in the direction of the turbine 3. In the process, they pass through the dividing elements 11a, 11b and the elastomer valves 15a, 15b, and also the turbine openings 9a, 9b, and thus pass into the flow channel portions 21a, 21b.

[0065] The suction operation mode of the vacuum cleaner 1 is in particular characterized in that a negative pressure prevails in the dust collecting tank 5 and in the chambers 6a, 6b that participate in suction operation. This negative pressure also prevails in the flow channel portions 21a, 21b of the chambers 6a, 6b participating in suction operation. The negative pressure is generated by the turbine 3 and the motor 22 and is responsible for the formation of the air streams 4a and 4b that allow air and dust to be sucked into the vacuum cleaner 1.

[0066] As a result of the suction operation of the vacuum cleaner 1, the filter elements 7a, 7b can become clogged with dust, with the result that the filtering capacity is reduced. This can represent a risk to the motor 22 and the turbine 3 when these components of the vacuum cleaner 1 are exposed to too much dust. Therefore, the filter elements 7a, 7b of the filter device 2 are regularly dedusted so that for example solidified filter cake 24 can be detached from the filter elements 7a, 7b. To this end, a filter dedusting process is initiated in one of the two chambers 6a, 6b. The start of filter dedusting of the second chamber 6b is illustrated starting with FIG. 3.

[0067] In the following text, a filter dedusting process of the second chamber 6b of the vacuum cleaner 1, or of the filter element 7b of the second chamber 6b of the vacuum cleaner 1 is described. This filter dedusting process is started by actuating the valve 10b, which is shifted from the suction operation position into the filter dedusting position. As a result, the turbine opening 9b of the second chamber 6b closes (opening 9b being closed as shown, e.g., in FIG. 3, with the opening 9b being open shown in FIG. 6), while the inflow opening 8b of the second chamber 6b is opened. The inflow opening 8b is connected in a conducting manner to a ventilation channel 20b, which in turn is connected in terms of flow to the environment of the vacuum cleaner 1. As a result of this fluidic connection between the outflow opening 8b and the environment of the vacuum cleaner 1, a pressure equalizing air stream can pass into the second chamber 6b through the inflow opening 8b and so a substantial weakening of the negative pressure in the second chamber 6b occurs. The pressure equalizing air stream is illustrated in the right-hand half of FIG. 3 by the dashed-line air flow. It passes from the environment of the vacuum cleaner into the second chamber 6b through the ventilation channel 20b of the second chamber 6b. In the second chamber 6b, the pressure equalizing air stream ensures that the elastomer valve 15b bears against the membrane plate 14b, with the result that the dividing element 11b is no longer permeable to the air stream 4b. The closing movement of the elastomer valve 15b is indicated by the arrow in FIG. 3. In other words, as a result of the closing of the valve 10b and the closing, caused thereby, of the elastomer valve 15b, the air stream 4b is blocked and the suction stream 4b through the second chamber 6b of the vacuum cleaner 1 is interrupted.

[0068] At the same time, as a result of the rapid penetration of the pressure equalizing air stream into the second chamber 6b, the pleats 12b (see, e.g., FIG. 1) are moved from their parked position into the dedusting position. The pulse that is transported into the second chamber 6b by the pressure equalizing air stream ensures an abrupt switchover or folding over of the pleats 12b such that the dividing element 11b likewise moves abruptly in the direction of the filter element 7b, touches the latter and transmits the pulse of the pressure equalizing impact to the filter element 7b. This results in substantial mechanical shaking of the filter element 7b, wherein an intensity of the shock is set such that any solidified filter cake 24 can be detached from the filter element 7b. Furthermore, it is also possible for loose dust located in the filter element 7b to be shaken off by the mechanical shaking. As illustrated in FIG. 4, the detached filter cake 24 drops into the dust collecting tank 5 so that it can be disposed of later together with the rest of the sucked-in dust. It is apparent from FIGS. 3 and 4 that, during the dedusting of the filter element 7b in the second chamber 6b of the vacuum cleaner 1, the air stream 4b is blocked, while the air stream 4a can continue to flow through the first chamber 6a of the vacuum cleaner 1.

[0069] Provision can also be made according to the invention for the transmission of the pulse of the pressure equalizing air stream between the dividing element 11b and the filter element 7b to take place in a contactless manner. In this case, the dividing element 11b and the filter element 7b are designed such that the abrupt compression of the air in the front region 17b of the second chamber 6b is enough to bring about sufficiently great mechanical shaking of the filter element 7b. The exploitation of a pulse of a pressure equalizing air shock for providing efficient filter dedusting with simultaneously continuing suction operation of a vacuum cleaner can preferably also be referred to as backflushing or a backflushing process according to the invention.

[0070] FIG. 5 shows a schematic illustration of the vacuum cleaner 1 at the end of the dedusting process of the second chamber 6b. The end of the dedusting process is again started by actuation of the valve 10b. In particular, the valve 10b is now slid back from the dedusting position into the suction position. As a result, the turbine opening 9b is opened again, while the inflow opening 8b, which allows the flow connection with the environment of the vacuum cleaner 1, is closed. As a result, a negative pressure can build up in the second chamber 6b again, as is necessary for carrying out suction operation. In particular, a suction air stream 4b flows again from the dust collecting tank 5 into the second chamber 6b and the elastomer valve 15b of the dividing element 11b opens again. The opening movement of the elastomer valve 15b is indicated by the white arrow in FIG. 5. Furthermore, the membrane plate 14b passes from the dedusting position back into the parked position. This is brought about in particular by a further switchover or folding over of the pleats 12b, which likewise jump back from the dedusting position into the parked position of suction operation. Furthermore, the movement of the membrane plate 14b from the parked position into the suction operation position is supported by additional restoring forces, which result from the incipient flow through the dividing element 11b.

[0071] FIGS. 6 to 8 show a filter dedusting process of the first chamber 6a of the filter device 2. In this case, the contents of FIGS. 3 and 6, 4 and 7 and 5 and 8 correspond in each case, wherein the reference signs “b” in the description should be replaced by an “a”. Therefore, a detailed explanation of FIGS. 6 to 8 will not be given. It is apparent from FIGS. 6 and 7 that, during the dedusting of the filter element 7a in the first chamber 6a of the vacuum cleaner 1, the air stream 4a is blocked, while the air stream 4b can continue to flow through the second chamber 6a of the vacuum cleaner 1.

[0072] FIG. 9 shows possible configurations of the pleat 12a, 12b. The inner region of the pleat 12 is formed by an elastomer pleat, which preferably consists of elastic material. It preferably has an indentation, which may have for example the shape of a cross or of an open rectangle. The elastomer pleat is preferably surrounded by the membrane plate 14, which connects the pleat 12 to the dividing element.

[0073] FIG. 10 shows a schematic side view of a vacuum cleaner 1 having a preferred embodiment of the filter device 2 in a horizontal arrangement. What is illustrated is a vacuum cleaner 1 having a vacuum cleaner head 23 in an upper region and a dust collecting tank 5 in a lower region of the vacuum cleaner 1. The turbine 3 and the motor 22 are provided in the vacuum cleaner head 23. The dust collecting tank 5 has a suction hose inlet 19 for connecting a suction hose. Provided in the dust collecting tank 5 are two chambers 6a, 6b, which, in the configuration of the vacuum cleaner 1 illustrated in FIG. 10, are flowed through by air streams 4a, 4b that flow from bottom to top, while the direction of flow in the vacuum cleaner 1 in FIG. 1 (vertical arrangement of the chambers 6a, 6b) is in a lateral direction from right to left or from left to right.

[0074] On flowing through the chambers 6a, 6b, the air streams 4a, 4b first of all pass through the filter elements 7a, 7b before they pass through the inlet openings 13a, 13b into the front part 17a, 17b of the chambers 6a, 6b. From there, the air streams 4a, 4b continue on their way through the dividing elements 11a, 11b and through the elastomer valves 15a, 15b until they pass, in suction operation, through the turbine openings 9a, 9b into the flow channel portions 21a, 21b upstream of the turbine 3. In the process, the turbine openings 9a, 9b are opened up by the valves 10a, 10b in the case of suction operation.

[0075] In the case of dedusting, the valves 10a, 10b can be slid into the dedusting position, such that the turbine openings 9a, 9b are then closed and the outflow openings 8a, 8b open. The inflow openings 8a, 8b are fluidically connected to the ventilation channels 20a, 20b, which are in a flow connection with the environment of the vacuum cleaner 1. In this way, pressure equalizing streams can pass into the chambers 6a, 6b through the outflow openings 8a, 8b. These pressure equalizing streams weaken the negative pressure in the chamber to be dedusted and close the elastomer valves 15a, 15b of the dividing elements 11a, 11b and ensure that the dividing elements 11a, 11b move in the direction of the filter elements 7a, 7b. The pulses of the pressure equalizing streams can then be transmitted from the membrane plate 14a, 14b to the filter elements 71, 7b by contact or contactlessly, with the result that the filter elements 7a, 7b are mechanically shaken. This in turn results in effective dedusting of the filter elements 7a, 7b.

[0076] Tests have shown that especially a horizontal arrangement of the filter device 2 can result in a particularly compact vacuum cleaner 1, in which the filter device 2 takes up only a little installation space.

LIST OF REFERENCE SIGNS

[0077] 1 Vacuum cleaner
2 Filter device
3 Turbine device
4 Main air stream, 4a: first main air stream, 4b: second main air stream
5 Collecting tank
6 Chamber, 6a: first chamber, 6b: second chamber
7 Filter element, 7a: first filter element, 7b: second filter element
8 Inflow opening, 8a: first inflow opening, 8b: second inflow opening
9 Turbine opening, 9a: first turbine opening, 9b: second turbine opening
10 Valve, 10a: first valve, 10b: second valve
11 Dividing element, 11a: first dividing element, 11b: second dividing element
12 Pleat, 12a: pleat in the first chamber, 12b: pleat in the second chamber
13 Inlet opening, 13a: first inlet opening, 13b: second inlet opening
14 Membrane plate, 14a: first membrane plate, 14b: second membrane plate
15 Elastomer valve, 15a: first elastomer valve, 15b: second elastomer valve
16 Gap, 16a: first gap, 16b: second gap
17 Front space in a chamber (17a: front space of the first chamber 6a, 17b: front space of the second chamber 6b)
18 Rear space in a chamber (18a: rear space of the first chamber 6a, 18b: rear space of the second chamber 6b)
19 Suction hose inlet
20 Ventilation channel
21 Flow channel portion

22 Motor

[0078] 23 Vacuum cleaner head
24 Filter cake
25 Partition wall