FILTER UNIT FOR A VACUUM CLEANER AND FILTER CLEANING PROCEDURE

Description

[0001] The invention relates, in a first aspect, to a filter device for a vacuum cleaner. The filter device has two chambers, at least one of which participates in the suction operation of the vacuum cleaner while a filter element of the other chamber can be cleaned. This allows the suction operation of the vacuum cleaner to be maintained by the other chamber while one filter element is being cleaned. This advantage is made possible by an elastic membrane that can change its shape or move when the chamber being cleaned is ventilated. Ventilation is achieved by a pressure equalization flow that can enter the chamber being cleaned through a ventilation channel and a ventilation opening. Through the movement of the membrane, the airflow is reduced by the pressure equalization flow.A change in the shape of the elastic membrane exerts a cleaning impulse on the filter element, which can, for example, cause a caked-on filter residue to be loosened and fall into the dust collection container of the vacuum cleaner. In a second aspect, the invention relates to a method for cleaning a filter assembly in a vacuum cleaner. Background of the invention:

[0002] Vacuum cleaners are often used on construction sites to pick up dirt particles such as dust, drilling debris, or similar materials. A turbine creates a vacuum inside the vacuum cleaner to collect the dirt. This vacuum is then used via a hose connected to the vacuum to draw in the dirt particles and transport them to a collection container. Standard vacuum cleaners are typically designed so that the turbine, a filter, the collection container, and the inlet for the vacuumed dirt particles are arranged in a linear flow path. The filter is usually positioned between the collection container or the inlet for the vacuumed dirt particles and the turbine that generates the vacuum. Since the air, now laden with dirt particles, would otherwise flow through the turbine and consequently clog it, a filter is often used to prevent clogging.The filter, which would otherwise damage the turbine, serves to clean the intake air and thus, in particular, to protect the turbine.

[0003] A problem can arise, however, if the filter can no longer function adequately and can no longer filter out the vacuumed dirt particles from the air flowing through it. This is particularly the case if the filter becomes increasingly dirty, i.e., filled with dirt particles, due to prolonged use of the vacuum cleaner. To keep the filter functioning, it must be cleaned periodically and freed of the collected dirt particles. However, cleaning the filter on conventional vacuum cleaners requires switching off the operation, opening the vacuum, and removing the filter to empty the trapped dirt particles. Such actions interrupt the vacuuming process and are very time-consuming.

[0004] According to the prior art, vacuum cleaners already exist that have a device for cleaning the filter without requiring the vacuum cleaner to be switched off, opened, and the filter removed to remove the collected dirt particles. However, a disadvantage of such devices is that the vacuum cleaner's operation must still be interrupted during filter cleaning. This also increases the time required for cleaning. Furthermore, such known filter cleaning devices are often complex and composed of many components. As a result, conventional filter cleaning devices, as known from the prior art, are frequently prone to malfunctions, wear, or require maintenance.

[0005] For example, DE 10 2016 101 414 A1 discloses a vacuum cleaning device, such as a battery-powered handheld vacuum cleaner, wherein an air filter of the vacuum cleaning device can be flushed in a direction opposite to the suction direction during regeneration. In this backflushing-based filter cleaning process, the filter is, in particular, mounted in a repositionable manner within the vacuum cleaning device.

[0006] The object of the present invention is therefore to overcome the above-described shortcomings and disadvantages of the prior art and to provide an improved filter device for a vacuum cleaner with which the vacuuming operation of the vacuum cleaner does not have to be interrupted during the cleaning of the filter.

[0007] The problem is solved by the subject matter of the independent claims. Advantageous embodiments of the subject matter according to the invention are described in the dependent claims. Description of the invention:

[0008] The problem is solved in a first aspect by a filter device for a vacuum cleaner, wherein the filter device comprises a turbine and a motor for generating a first main airflow and / or a second main airflow in the vacuum cleaner.The filter device is characterized by a first chamber and a second chamber, each comprising a filter element, a ventilation opening, and a turbine opening, wherein during suction operation through at least one of the chambers the turbine opening of the respective chamber is open, so that a flow connection exists between the chamber and the turbine device, and the ventilation opening is closed, so that a negative pressure prevails in the chamber, wherein a cleaning process of a filter element is initiated by actuating a valve, so that a pressure equalization flow caused by a pressure change enters the chamber, wherein the pressure change closes the turbine opening by means of an elastic membrane and exerts a cleaning impulse on the filter element.

[0009] Tests have shown that the proposed filter system ensures high and uninterrupted suction performance, even during filter cleaning of one of the two chambers. Thanks to the elastic membrane and its design, as well as the resulting controlled pressure distribution in the different areas of the vacuum cleaner, alternating cleaning of the two chambers is possible while the other chamber continues to operate. This advantageously provides a highly efficient and space-optimized filter cleaning solution for the vacuum cleaner. The proposed filter system is particularly simple in design. Application tests have shown that the proposed filter system is especially robust and not prone to repairs or wear.These advantages of the invention are particularly due to the elastic membrane, which, according to a preferred embodiment of the invention, comprises an elastic material and can change its shape or move when it is subjected to pressure or experiences a change in pressure conditions.

[0010] It is preferred, according to the invention, that the elastic membrane exhibits high elongation behavior within its elastic range. For example, elongations in a range between 150 and 300% are possible. Materials that can be used, for example, in the manufacture of the elastic membrane are synthetic rubbers such as chloroprene rubber (CR) or styrene-butadiene rubber (SBR / SCR).

[0011] It is preferred according to the invention that the closing of the turbine opening is effected by a change in shape and / or by a movement of the elastic membrane. The elastic membrane is preferably in a relaxed state when a negative pressure exists in the corresponding chamber of the vacuum cleaner and the chamber participates in the suction operation of the vacuum cleaner. In this relaxed state, the elastic membrane can, for example, be arranged substantially horizontally within a chamber. Possible arrangements of the elastic membrane in the relaxed state are shown, for example, in the Figs. 1 to 3 depicted.

[0012] In the chambers participating in the vacuum cleaner's suction operation, the elastic membrane is preferably in a relaxed state. During this suction operation, a suction flow is generated from the vacuum cleaner's dust collection container to the vacuum cleaner's turbine, with this suction or main airflow passing particularly through the chambers participating in the suction operation. The transition between the chambers and the turbine is preferably marked by the turbine openings of the chambers. Flow channel sections extend between the turbine openings of the chambers and the turbine, and are thus arranged between the turbine and the turbine openings of the chambers. It is preferred, according to the invention, that the flow connection between the chambers and the turbine assembly is formed by flow channel sections.

[0013] On its way from the vacuum cleaner's dust collection container to its turbine, the suction flow first passes through filter elements designed to capture and filter out a significant portion of the dust present in the air. This is because excessive dust would pose a danger to the vacuum cleaner's turbine and motor if it were to enter these areas. According to the invention, it is preferred that the proposed vacuum cleaner or filter assembly incorporates two filter elements, each connected to a separate chamber. This means that the suction flow drawn into the collection container through a vacuum hose inlet is split into two main airflows. A first main airflow passes through the first chamber to the turbine, while a second main airflow passes through the second chamber to the turbine.From a fluid dynamics perspective, filter elements are positioned upstream of both chambers, filtering dust from the main air streams. According to the invention, the inlet area of ​​the chambers is preferably referred to as the inlet opening, with the inlet openings being closed off from the collection container by the filter elements.

[0014] In accordance with the invention, it is preferred that, during suction operation, the main airflows pass from the dust collection container, through the filter elements and the inlet openings into the chambers, with the main airflows passing further into the flow channel sections through the open turbine openings. This advantageously creates a flow path between the suction hose inlet in the collection container and the turbine.

[0015] During operation, the filters of the proposed filter system can become clogged. This can occur, for example, when a filter cake bakes onto or adheres to the filter, blocking it or reducing its filtration efficiency. To clear the filter elements and increase their filtration efficiency, a filter cleaning process can be performed. In this context, providing two chambers with two filter elements that can be cleaned alternately has proven to be very advantageous. A significant advantage of the proposed invention is that the filter element of one of the two chambers can be cleaned by the other chamber while the vacuuming operation continues.This eliminates the need to interrupt the vacuum cleaner's operation for filter cleaning, resulting in significant time savings and increased efficiency for the user compared to conventional devices that must be switched off during filter cleaning. In particular, the advantages of the invention stem from the division of the suction flow into two main airflows that can flow through different chambers. Furthermore, the elastic membrane contributes to the success of the proposed filter device according to the invention. Due to its elastic properties, this membrane can change its shape or is designed to be movable, enabling it to close the turbine opening of the chamber to be cleaned during ventilation or cleaning and to exert a cleaning impulse on the filter element.

[0016] To initiate a cleaning process, the chamber whose filter element is to be cleaned is vented. The term "venting" is used within the meaning of the invention to denote a weakening or collapse of the negative pressure in the chamber to be cleaned. Venting is preferably achieved by allowing the valve, which is present in each of the two chambers, to be moved into a venting position. During suction operation through one chamber, the valve is in a suction operating position in which it closes the chamber's vent opening. As a result, the dust collection container, the chambers participating in the suction operation, and the flow channel sections extending from the turbine openings to the turbine form a negative pressure zone within the vacuum cleaner. These negative pressure zones are located in the Figs. 3 to 9 dark colored.

[0017] To initiate the cleaning process, the valve can be moved from the suction position to a cleaning position. This can be achieved by a simple push motion of the valve. Preferably, actuating the valve opens the ventilation opening. It is particularly preferred, according to the invention, that the valves can be moved by actuators. Preferably, the valves can have openings, the openings of which can be aligned with the ventilation openings by moving the valves. When the valve openings coincide with the ventilation openings of the chamber to be cleaned, a flow connection is created between the ventilation openings and ventilation channels located between the vacuum cleaner head and the dust collection container, which are in fluidic communication with the vacuum cleaner's surroundings.

[0018] An airflow can enter the chamber to be cleaned through the ventilation openings, and this ventilation airflow can preferably also be referred to as a pressure equalization flow according to the invention. It is preferred according to the invention that the ventilation openings are arranged between the chambers and ventilation channels. The pressure equalization flow flows from the environment of the vacuum cleaner through the ventilation channels and the open ventilation openings into the chamber to be cleaned, thereby weakening or reducing the negative pressure there. In other words, the pressure equalization flow ensures that the pressure in the chamber to be cleaned adjusts to or aligns with the external or ambient pressure of the vacuum cleaner. The pressure equalization flow is located in the Fig. 4 , 5 , 7 and 8 indicated by a dashed arrow.

[0019] The equalization of the pressure conditions in the chamber to be cleaned with the vacuum cleaner environment or the ambient pressure is preferably also referred to, within the meaning of the invention, as a pressure change caused by the pressure equalization flow. It is preferred within the meaning of the invention that the equalization of the pressure conditions or the pressure change causes the elastic membrane in the chamber to be cleaned to move and / or change its shape. In particular, the elastic membrane can transition from its relaxed suction operating state to a pressurized state. For example, the elastic membrane can transition from a first, relaxed state to a second state, wherein the membrane, in this second state, for example, closes the turbine opening of the chamber to be cleaned. This closing of the turbine opening by the elastic membrane is described, for example, in the Fig. 4 and 7As illustrated. It is preferred according to the invention that, in the first, relaxed state, the elastic membrane leaves the turbine opening open and allows the main airflow to pass through the corresponding chamber of the vacuum cleaner. In other words, during suction operation, a main airflow can develop from the collection container to the turbine, and this main airflow can pass through the chamber participating in the suction operation unimpeded by the elastic membrane. It is further preferred according to the invention that, in the second, pressurized state, the elastic membrane closes the turbine opening, so that the main airflow through the corresponding chamber of the vacuum cleaner is blocked and the suction operation through this chamber is interrupted.

[0020] In accordance with the invention, it is preferred that the elastic properties of the elastic membrane are designed in such a way that the elastic membrane can continue to move in the event of ventilation and, for example, adhere to the inner walls of the chamber to be cleaned (cf. Fig. 5 and 8 The application of the elastic membrane to the inner walls of the chamber to be cleaned can be referred to as the third state of the elastic membrane within the meaning of the invention. It is preferred within the meaning of the invention that the transition of the elastic membrane from the first state to the second or third state, or back, is referred to as a change in shape or movement of the elastic membrane. Preferably, the elastic membrane can assume not only these three described states, but also all conceivable intermediate steps or states.

[0021] In particular, the elastic membrane is preferably configured to compress the air previously located between the membrane and the filter element to be cleaned, such that a pressure surge is generated, which, according to the invention, is referred to as a cleaning pulse or cleaning shock. This compression pressure surge is transmitted to the filter element and advantageously leads to backwashing of the filter and / or mechanical vibration of the filter element. The intensity or strength of the cleaning pulse is preferably designed such that baked-on filter cake detaches from the filter element and falls into the dust collection container of the vacuum cleaner, so that it can be disposed of at a later time. According to the invention, the transmission of the compression pressure surge is also referred to as the application of a cleaning pulse to the filter element.

[0022] The upper part of the vacuum cleaner consists of a vacuum head, while the lower part comprises the dust collection container. The vacuum head houses components such as the turbine and motor, which generate the vacuum necessary to draw in dust particles and drilling debris. Ventilation channels are provided between the vacuum head and the dust collection container, allowing air from the surrounding environment to be drawn in through openings in the housing. This air, drawn in through the ventilation channels, can, for example, create a pressure equalization flow, thus equalizing the pressure in the chamber being cleaned or adjusting the pressure there to the ambient pressure. The collection container may also have a hose inlet to which a vacuum hose can be connected.In accordance with the invention, it is preferred that the ventilation channels are arranged between a dust collection container and a vacuum cleaner head of the vacuum cleaner.

[0023] It is preferred, according to the invention, that the turbine opening is configured to allow a flow connection between one of the chambers and the turbine, wherein this flow connection between the chambers and the turbine assembly exists particularly during operation of the vacuum cleaner. Preferably, the flow connection is formed by a flow channel section located between the turbine opening of one of the chambers and the turbine. This flow channel section is open, particularly during operation of the vacuum cleaner, so that the negative pressure generated by the turbine can be used for drawing in or sucking up dust.

[0024] It is preferred according to the invention that a negative pressure exists in the corresponding chamber when the associated ventilation opening is closed and the turbine opening is open. In this case, suction operation takes place through the corresponding chamber, and dust particles can be drawn into the collection container with the associated main airflow. It is further preferred according to the invention that, during suction operation through one chamber, the filter element in the other chamber can be cleaned.

[0025] It is preferred, according to the invention, that the ventilation channels are arranged between the collection container and the vacuum head. The collection container forms the lower part of the vacuum cleaner, in which the dust sucked up by the vacuum cleaner is collected and stored until the vacuum cleaner is emptied. It is preferred, according to the invention, that the first and second chambers are part of the collection container. In other words, the first and second chambers are arranged within the collection container of the vacuum cleaner. In a preferred embodiment of the invention, the chambers have inlet openings that are separated from the collection container by filter elements.Preferably, the filter elements are configured to close the inlet openings in such a way that dust particles can be filtered out of the main airflows, which, during suction operation, form between the suction hose inlet of the dust collection container and the turbine. It is these filter elements, located between the chambers and the remaining volume of the collection container, that are to be cleaned in the context of the present invention. Due to the direct and immediate connection between the filter elements and the collection container, dust particles and filter cakes that are detached from the filter elements during cleaning can pass directly into the collection container and be disposed of when the container is next emptied.

[0026] The suction head preferably forms the upper part of the vacuum cleaner; it is also preferably referred to as the "vacuum cleaner head". The suction head preferably comprises the turbine assembly of the vacuum cleaner and a motor. Ventilation channels are arranged between the suction head and the collection container, which can be bounded externally, i.e., in relation to the environment of the vacuum cleaner, by sections of the vacuum cleaner housing. These sections of the vacuum cleaner housing preferably have ventilation openings or slots through which air can be drawn into the interior of the vacuum cleaner. It is particularly preferred, according to the invention, that the air is drawn into the ventilation channels, from where it can then enter the chambers of the proposed filter assembly.In a particularly preferred embodiment of the invention, the airflow from the ventilation duct into the chamber to be cleaned forms a pressure equalization flow, which can enter the chamber through the open valve and the ventilation opening from the ventilation duct. In other words, when the valves are opened, a pressure equalization flow can enter the chambers of the vacuum cleaner. It is preferred, according to the invention, that the valves can each be moved, i.e., opened or closed, by means of an actuating element.

[0027] It is preferred according to the invention that a negative pressure exists in the collection container and in at least one of the two chambers during operation of the vacuum cleaner. Preferably, the negative pressure can be generated by the turbine assembly in the vacuum head. Dust particles or drilling dust can be drawn into the interior of the vacuum cleaner by means of the negative pressure. The collection container of the vacuum cleaner preferably has a suction hose inlet through which the dust particles or drilling dust can be drawn in, particularly when the inlet is connected to a suction hose and the vacuum cleaner is operated in suction mode. The suction mode is preferably characterized in that the vacuum cleaner generates a negative pressure with its turbine assembly.During the suction operation, main airflows are generated through the chambers of the vacuum cleaner that participate in the suction operation, with the main airflows preferably flowing from the vacuum hose inlet to the turbine device.

[0028] In a second aspect, the invention relates to a method for cleaning a filter device in a vacuum cleaner, wherein the method is characterized by the following steps: a) Provision of a proposed filter device in a vacuum cleaner, b) Operation of the vacuum cleaner, wherein a negative pressure exists in a collection container of the vacuum cleaner and in at least one chamber of the vacuum cleaner during operation, c) Actuation of a valve, whereby a ventilation opening is opened, so that a pressure equalization flow causing a pressure change enters the chamber and, by the pressure change, a turbine opening of the chamber is closed by an elastic membrane, d) Cleaning of a filter element by a cleaning pulse exerted on the filter element by the elastic membrane.

[0029] It is preferred, according to the invention, that the vacuum cleaner to be provided has a filter device comprising two chambers, each with a filter element, a ventilation opening, and a turbine opening. Elastic membranes are provided in each chamber, which can assume different shapes or states depending on the pressure conditions within the chambers. For example, in a relaxed state, the elastic membranes can be arranged in a substantially horizontal configuration within the chambers, with this relaxed state being assumed particularly during suction operation of the vacuum cleaner. It is preferred, according to the invention, that a negative pressure prevails in the chambers participating in the suction operation.

[0030] It is preferred in accordance with the invention that the elastic membranes can move or change their shape, i.e., their state, when the pressure conditions in the chambers change. For example, if one of the chambers is vented and the pressure in the vented chamber to be cleaned equals the ambient pressure, the elastic membrane can bend and, for example, assume a second state, wherein in this second state the elastic membrane seals the turbine opening of the corresponding chamber (cf. Fig. 4 and 7 The bending can also include deformation of the elastic membrane or material. Sealing the turbine opening blocks the main airflow through this chamber, and the chamber no longer participates in the vacuum cleaner's suction operation, while the vacuum cleaner's suction operation is maintained by the other, unventilated chamber.

[0031] The elastic membrane can bend or deform further, more strongly, and, for example, assume a third state in which the elastic membrane lies against the inner walls of the chamber to be cleaned (cf. Fig. 5 and 8In this state, the elastic membrane compresses the air previously located between the filter element and the membrane so strongly that a pressure surge is transmitted to the filter element. This pressure surge causes a mechanical vibration of the filter element, dislodging any filter cake adhering to it so that it can fall into the dust collection container. According to the invention, it is preferred to refer to the first, or relaxed, state of the elastic membrane as the park state or park position, while the second state, in which the elastic membrane closes the turbine opening, can be referred to as the closed position. Preferably, the third state of the elastic membrane can be referred to as the cleaning state, cleaning position, or cleaning position.

[0032] It is preferred according to the invention that the actuation of the valve opens the ventilation opening of the chamber to be cleaned, allowing a ventilation or pressure equalization flow to enter the chamber. This ventilation or pressure equalization flow is preferably configured to cause the change in shape or movement of the elastic membrane, leading to changes in the membrane's state. It is preferred according to the invention that these changes in the elastic membrane's state generate a cleaning impulse that effects the cleaning of the filter element. Preferably, the elastic membrane is configured to exert a cleaning impulse on the filter element. It is particularly preferred according to the invention that the cleaning impulse is generated by a movement, change in shape, position, or state of the elastic membrane.

[0033] A significant advantage of the invention is that the cleaning of the filter element of one of the two chambers is carried out by the other chamber during continued suction operation. In particular, the proposed filter device, i.e., especially the elastic membrane, can provide a pressure-controlled valve for the turbine openings of the chambers, and the filter device can also be compactly integrated into a vacuum cleaner. Furthermore, the invention allows for a robust basic structure of a vacuum cleaner, since the proposed filter device has a comparatively small number of mechanical components. A particular advantage of the invention is the exceptionally high compression rate with which the remaining air within the chamber to be cleaned is compressed when the elastic membrane transitions from the second to the third state.This surprisingly high compression rate allows for particularly effective cleaning efficiency to be achieved with a comparatively small residual volume of air to be moved.

[0034] In particular, the invention also relates to a vacuum cleaner with a filter device according to the invention. The definitions, technical effects and advantages described for the proposed filter device apply analogously to the proposed filter cleaning method and the vacuum cleaner that has a proposed filter device.

[0035] It is preferred according to the invention that the valves are designed as spool valves. They constitute a control element with which the turbine opening or the ventilation opening can be closed or opened. The spool valves can be designed as flat elements, although round or other shapes may also be preferred according to the invention.

[0036] Further advantages will become apparent from the following description of the figures. The figures illustrate various embodiments of the present invention. The figures, the description, and the claims contain numerous features in combination. It will be advantageous for those skilled in the art to also consider the features individually and combine them into meaningful further combinations.

[0037] In the figures, identical and similar components are numbered with the same reference symbols.

[0038] They show: Fig. 1 Schematic side view of a preferred embodiment of the proposed filter device. Fig. 2 Schematic representation of the vacuum cleaner while both chambers are participating in suction operation. Fig. 3 Further schematic representation of the vacuum cleaner while both chambers are participating in suction operation, in particular the pressure conditions in the vacuum cleaner. Fig. 4 Schematic representation of the vacuum cleaner while the filter element of the second chamber is being cleaned. Fig. 5 Schematic representation of the vacuum cleaner while the filter element of the second chamber is being cleaned. Fig. 6 Schematic representation of the vacuum cleaner at the end of the cleaning process of the second chamber. Fig. 7 Schematic representation of the vacuum cleaner while the filter element of the first chamber is being cleaned. Fig. 8 Schematic representation of the vacuum cleaner while the filter element of the first chamber is being cleaned. Fig. 9 Schematic representation of the vacuum cleaner at the end of the cleaning process of the first chamber. Examples of implementation and description of figures:

[0039] Fig. 1 Figure 1 shows a schematic side view of a preferred embodiment of the proposed filter device 2. For clarity, in Fig. 1 a first chamber 6a is shown, which is located in the Figs. 3 to 9 the left of the two chambers 6a, 6b. This is shown in Fig. 1The first chamber 6a has a first inlet opening 13a, a first ventilation opening 8a, and a turbine opening 9a. The first chamber 6a is located in an upper area of ​​the dust collection container 5 of the vacuum cleaner 1 and is sealed off from the dust collection container 5 by a filter element 7a. When, during vacuuming operation, a first suction stream 4a flows from the dust collection container 5 towards the turbine 3 of the vacuum cleaner 1, the dust-laden air passes through the filter element 7a, whereby a large portion of the dust is filtered out of the suction stream 4a. In this way, the turbine 3 and the motor 22 of the vacuum cleaner 1 are protected from contamination. The suction stream 4a is then... Fig. 1 symbolized by the dashed arrows.

[0040] Within the first chamber 6a, an elastic membrane 11a is arranged, which is located in the Fig. 1The illustrated embodiment is in the relaxed or first state. This state of the elastic membrane 11a is preferably also referred to as the suction operating state within the meaning of the invention. In this state, the elastic membrane 11a does not impede or block the suction flow through the first chamber 6a, but instead allows it to pass through essentially unimpeded. It is preferred within the meaning of the invention that the elastic membrane 11a in the first state is arranged essentially horizontally in the first chamber 6a, and that the elastic membrane 11a is fixed to the side walls of the first chamber 6a. In particular, the elastic membrane 11a can be clamped or fastened between projections of the side walls of the first chamber 6a. However, other fastening methods are also conceivable, as long as they allow movement of the elastic membrane 11a within the first chamber 6a.The elastic membrane 11a is specifically designed to allow an inner region of the membrane 11a to move within the first chamber 6a. This mobility is advantageously due to the highly elastic properties of the elastic membrane 11a. The mobility of the elastic membrane 11a can also be expressed by a change in shape or state of the elastic membrane 11a. For the purposes of the invention, the term "change in shape or state" preferably means that the elastic membrane 11a can, for example, bend or adapt its shape to or conform to other objects, wherein such a change in shape or state of the elastic membrane 11a is brought about in particular by a change in the pressure conditions in the chamber 6a.This can occur, for example, if the negative pressure prevailing in chamber 6a during suction operation is weakened by venting the chamber 6a, so that the pressure in chamber 6a adjusts to or equals the pressure in the vicinity of the vacuum cleaner ("ambient pressure"). Depending on the magnitude of the pressure change, the elastic membrane 11a can bend or move to a greater or lesser extent and, for example, assume a closed state (see...). Fig. 4 and 7 ), in which the elastic membrane 11a closes a turbine opening 9a of the chamber 6a, or the elastic membrane 11a can assume a cleaning state (cf. Fig. 5 and 8), in which the elastic membrane 11a adheres to the inner side walls of chamber 6 and, on its way there, compresses the residual air remaining in chamber 6 so strongly that a cleaning or pressure surge impulse is exerted on the filter element 7 to be cleaned. This cleaning impulse causes a mechanical vibration of the filter element 7, which leads to the cleaning of the filter element 7a.

[0041] The ventilation of the first chamber 6a can be effected by actuating the valve 10a. By moving the valve 10a, the ventilation opening 8a of chamber 6a can be released or opened. Preferably, the valve 10a can be moved from a suction operating position (valve 10a closes the ventilation opening 8a) to a ventilation position (valve 10a releases the ventilation opening 8a) by means of an actuator 12a. In the ventilation position, a pressure equalization flow 15 from a ventilation channel 20a can enter chamber 6a and thus cause a pressure change in chamber 6a. The pressure change preferably consists of the escape of a negative pressure prevailing in chamber 6a during suction operation, which is replaced by an ambient pressure corresponding to the pressure in the vicinity of the vacuum cleaner 1.The valve 10a can have openings 14a which can coincide with the ventilation opening 8a by moving the valve 10a, so that the ventilation opening 8a of the chamber 6a is released, allowing the pressure equalization flow 15 from the ventilation channel 20a to enter the chamber 6a to be cleaned.

[0042] Fig. 1Figure 1 schematically shows a first chamber 6a of the proposed filter device 2 in suction operation, in which the turbine opening 9a of the first chamber 6a is open and the ventilation opening 8a of the first chamber 6a is closed. The suction flow 4a flows from the dust collection container 5 through the first chamber 6a and exits it in the region of the turbine opening 9a. The turbine opening 9a opens into a flow channel section 21a, which connects the turbine opening 9a of the first chamber 6a to the turbine 3. Within the context of the invention, it may be provided that a further opening, referred to as a bypass capillary 16a, is located between the chamber 6a and the flow channel section 21a. It is preferred within the scope of the invention that the bypass capillary 16a is configured to ensure equal or substantially equal pressure conditions above and below the membrane 11 in order to guarantee the parking position of the membranes 11a and 11b.

[0043] Fig. 2Figure 1 shows a schematic representation of the vacuum cleaner 1 while both chambers 6a and 6b of the vacuum cleaner 1 are operating. The dust collection container 5, which has a suction hose inlet 19, is shown in a lower section of the vacuum cleaner 1. A suction hose, which may be connected to a floor nozzle, for example, can be attached to this suction hose inlet 19. Dust particles or drilling dust can be sucked in through the suction hose. The sucked-in dust then passes through the suction hose inlet 19 into the dust collection container 5 of the vacuum cleaner 1.

[0044] The upper section of the vacuum cleaner 1 is formed by a vacuum cleaner head 23. The vacuum cleaner head contains, for example, the turbine 3 and the motor 22, which generate the negative pressure for sucking in the dust particles and drilling debris. Ventilation channels 20a and 20b are provided between the vacuum cleaner head 23 and the dust collection container 5, allowing air from the environment of the vacuum cleaner 1 to be drawn in through openings in the housing. This air drawn in through the ventilation channels 20 and 20b can, for example, form a pressure equalization flow 15 if pressure equalization is required in the vacuum cleaner 1. Pressure equalization flows 15 are, for example, used in the Fig. 4 , 5 , 7 and 8As illustrated, pressure equalization flows 15 can be used, for example, to weaken the negative pressure within the vacuum cleaner 1 and to interrupt the suction flow 4a, 4b in one of the chambers 6a, 6b in order to perform filter cleaning. Cleaning of the filter elements 7a, 7b is necessary, for example, when the filter elements 7a, 7b of the proposed filter device 2 are clogged with dust. The initially loose dust can clump together to form a filter cake 24, which is difficult to remove from the filter elements 7a, 7b. The present invention advantageously provides a particularly effective filter cleaning process, in which, in particular, the suction operation of the vacuum cleaner 1 does not need to be interrupted during filter cleaning.

[0045] Between the dust collection container 5 and the vacuum cleaner head 23, two chambers 6a, 6b are provided, the filters 7a, 7b of which can be cleaned alternately according to the invention, while the vacuuming operation of the vacuum cleaner 1 can continue in the other chamber 6a, 6b. The chambers 6a, 6b are essentially identical in design, but axially symmetrical with respect to a partition 25 separating the two chambers.

[0046] In Fig. 2Both chambers 6a, 6b are in suction mode, and the elastic membranes 11a, 11b are in their relaxed, suction-operated state. In this state, a suction flow 4a, 4b can pass from the collection container 5 of the vacuum cleaner 1 into the area of ​​the turbine 3, with the suction flows 41a, 4b passing through chambers 6a, 6b. Specifically, the suction flows 4a, 4b pass through the turbine openings 9a, 9b, which are located between chambers 6a, 6b and the flow channel sections 21a, 21b. The flow channel sections 21a, 21b connect the turbine openings 9a, 9b to the turbine 3 and extend between them.

[0047] Chambers 6a and 6b also have ventilation openings 8a and 8b, which can be opened or closed by valves 10a and 10b. The valves 10a and 10b can be moved by actuators 12a and 12b and have openings 14a and 14b that can coincide with the ventilation openings 8a and 8b of chambers 6a and 6b. When the openings 14a and 14b of the valves 10a and 10b coincide with the ventilation openings 8a and 8b of chambers 6a and 6b, the ventilation openings 8a and 8b are open, and a pressure equalization flow 15 can enter a chamber 6a or 6b to be cleaned, thereby reducing or replacing the negative pressure that exists in chamber 6a or 6b during suction operation with the ambient pressure. The pressure equalization flow 15 passes from the environment of the vacuum cleaner 1 via a ventilation duct 20a, 20b into the chambers 6a, 6b.

[0048] Fig. 3Figure 1 shows another schematic representation of the vacuum cleaner 1 while both chambers 6a and 6b are participating in the suction operation. In particular, it shows Fig. 3 The pressure conditions in vacuum cleaner 1 during vacuuming operation. Into the Figs. 3 to 9 Areas of the vacuum cleaner 1 where a negative pressure exists are colored dark. During suction operation, a negative pressure exists particularly in the dust collection container 5, in the chambers 6a and 6b that participate in the suction operation, and in the flow channel sections 21a and 21b. The dashed lines in Fig. 3 The flow paths of the suction air streams 4a, 4b through the vacuum cleaner 1 are illustrated.

[0049] Fig. 4Figure 1 shows a schematic representation of the vacuum cleaner 1 while the filter element 7b of the second chamber 6b is being cleaned. To start the cleaning process, the valve 10b is actuated, thereby opening the vent 8b. A pressure equalization flow 15b can then enter chamber 6b and equalize the pressure. This pressure equalization preferably ensures that the negative pressure present in chamber 6b during suction operation is replaced by ambient pressure. In other words, when chamber 6b is vented and a pressure equalization flow 15b enters chamber 6b through the vent 8b, the pressure in the chamber adjusts to the ambient pressure. The pressure equalization flow 15b is then... Fig. 4 This is shown with dashed arrows in the right half of the image.

[0050] Due to pressure equalization, the elastic membrane 11b in chamber 6b undergoes a change in shape or state, thus closing the turbine opening 9b of the chamber 6b to be cleaned. This interrupts the suction flow 4b through the second chamber 6b, while the suction flow 4a continues to flow through the first chamber 6a, maintaining the suction operation of the vacuum cleaner 1. The suction flow 4a through the first chamber 6a of the vacuum cleaner 1 is Fig. 4 symbolized by the dotted line in the left half of the image.

[0051] It can be seen in Fig. 4 also a filter cake 24, which adheres to the second filter element 7b. The aim of the filter cleaning process, which is carried out in Fig. 4 is started. It then shows... Fig. 4, that a residual air volume 18b is enclosed between the elastic membrane 11b and the filter element 7b, whereby a ventilated space 17b is formed above the elastic membrane 11b and the inner top of the chamber 6b.

[0052] Fig. 5Figure 1 shows the cleaning state of the second chamber 6b of the vacuum cleaner 1. In this cleaning state, the elastic membrane 11b has moved further or changed its shape so that it now further closes the turbine opening 9b, but also rests against the inner walls of chamber 6b. On its way to this third state, the elastic membrane 11b has compressed the residual air volume 18b in such a way that the rapid compression transmits a cleaning impulse or compressed air pulse to the filter element 7b. The pulse mechanically shakes the filter element 7b, causing the filter cake 24 adhering to the filter element 7b to be shaken off and fall into the collection container 5 of the vacuum cleaner 1.

[0053] Fig. 6Figure 1 shows a schematic representation of the vacuum cleaner 1 at the end of the cleaning process in the second chamber 6b. To end the cleaning process, the valve 10b is actuated, thereby closing the previously opened ventilation opening 8b, so that a vacuum, required for suction operation, is once again built up in chamber 6b by the turbine 3. It is particularly preferred, according to the invention, that the vacuum builds up between the elastic membrane 11b and the filter element 7b. At the end of the cleaning process, the elastic membrane 11b has returned to its relaxed state, this return movement being supported by the renewed vacuum within chamber 6b. In particular, the renewed suction flow 4b generates additional restoring forces that act on the elastic membrane 11b and support it in returning to its relaxed state.After the cleaning process of the second chamber 6b or of the filter element 7b in the second chamber 6b is complete, both chambers 6a, 6b again participate in the suction operation of the vacuum cleaner 1, so that both suction flows 4a, 4b flow through the vacuum cleaner 1. In the in . Fig. 6 In the illustrated embodiment of the invention, the ventilation openings 8a, 8b of the chambers 6a, 6b are each closed, while the turbine openings 9a, 9b to the flow channel sections 21a, 21b are open.

[0054] Figs. 7 to 9 The figures show schematic representations of the vacuum cleaner 1 while the filter element 7a of the first chamber 6a is being cleaned. The figures and their contents essentially correspond to the Figs. 4 to 6 , where the reference symbol «b» in the description is to be replaced by an «a». Reference symbol list

[0055] 1 Vacuum cleaner 2 Filter unit 3 Turbine unit 4 Main airflow, 4a: first main airflow, 4b: second main airflow 5 Collection container 6 Chamber, 6a: first chamber, 6b: second chamber 7 Filter element, 7a: first filter element, 7b: second filter element 8 Vent opening, 8a: first vent opening, 8b: second vent opening 9 Turbine opening, 9a: first turbine opening, 9b: second turbine opening 10 Valve, 10a: first valve, 10b: second valve 11 Elastic diaphragm, 11a: first elastic diaphragm, 11b: second elastic diaphragm 12 Actuator, 12a: Actuator for the valve of the first chamber, 12b: Actuator for the valve of the second chamber 13 Inlet opening, 13a: first inlet opening, 13b: second inlet opening 14 Openings in the valve 15 Pressure equalization flow 16 Bypass capillary, 16a: first bypass capillary,16b: second bypass capillary 17 ventilated area between top of chambers and elastic membrane 18 residual air volume 19 suction hose inlet 20 ventilation duct 21 flow channel section 22 motor 23 vacuum cleaner head 24 filter cake 25 partition

Claims

1. Filter device (2) for a vacuum cleaner (1) having a turbine device (3) and a motor (22) for generating a first main air stream (4a) and / or a second main air stream (4b) in the vacuum cleaner (1), characterized by a first chamber (6a) and a second chamber (6b), each having a filter element (7a, 7b), a ventilation opening (8a, 8b) and a turbine opening (9a, 9b), wherein, during suction operation through at least one of the chambers (6a and / or 6b), the turbine opening (9a, 9b) of the respective chamber (6a and / or 6b) is open such that a flow connection exists between the chamber (6a and / or 6b) and the turbine device (3), and the ventilation opening (8a, 8b) is closed such that a negative pressure prevails in the chamber (6a and / or 6b), wherein a dedusting process of a filter element (7a or 7b) is initiated by actuation of a valve (10a or 10b), such that a pressure equalizing stream that brings about a change in pressure passes into the chamber (6a or 6b), wherein, as a result of the change in pressure, the turbine opening (9a or 9b) is closed by an elastic membrane (11a or 11b) and a dedusting pulse is applied to the filter element (7a or 7b).

2. Filter device (2) according to Claim 1, characterized in that the turbine opening (9a or 9b) is closed by a change in shape and / or by a movement of the elastic membrane (11a or 11b).

3. Filter device (2) according to Claim 1 or 2, characterized in that the valves (10a, 10b) are moved by actuators (12a, 12b).

4. Filter device (2) according to one of the preceding claims, characterized in that the ventilation openings (8a, 8b) are opened or closed by actuating the valves (10a, 10b).

5. Vacuum cleaner (1), which has a filter device (2) according to one of the preceding claims.

6. Vacuum cleaner (1) according to Claim 5, characterized in that a flow connection between the chamber (6a and / or 6b) and the turbine device (3) is formed by a flow channel portion (21a, 21b).

7. Vacuum cleaner (1) according to Claim 5 or 6, characterized in that the ventilation openings (8a, 8b) are arranged between the chambers (6a, 6b) and ventilation channels (20a, 20b).

8. Vacuum cleaner (1) according to Claim 7, characterized in that the ventilation channels (20a, 20b) are arranged between a dust collecting tank (5) and a vacuum cleaner head (23) of the vacuum cleaner (1).

9. Vacuum cleaner (1) according to Claim 8, characterized in that the valves (10a, 10b) have openings (14), wherein the openings (14) are able to be brought into correspondence with the ventilation openings (8a, 8b) by movement of the valves (10a, 10b), with the result that a flow connection is established between the ventilation openings (8a, 8b) and the ventilation channels (20a, 20b).

10. Vacuum cleaner (1) according to one of Claims 6 to 9, characterized in that the main air streams (4a, 4b) pass from the dust collecting tank (5), through the filter elements (7a, 7b) and through inflow openings (13a, 13b) into the chambers (6a, 6b), wherein, during suction operation, the main air streams (4a, 4b) pass further, through the open turbine opening (9a, 9b), into the flow channel portions (21a, 21b).

11. Method for dedusting a filter device (2) in a vacuum cleaner (1), wherein the method is characterized by the following steps: a) providing a filter device (2) according to one of Claims 1 to 4 or providing a vacuum cleaner (1) according to one of Claims 5 to 10, b) operating the vacuum cleaner (1), wherein, during operation of the vacuum cleaner (1), a negative pressure prevails in a collecting tank (5) of the vacuum cleaner (1) and in at least one chamber (6a or 6b) of the vacuum cleaner (1), c) actuating a valve (10a or 10b), with the result that a ventilation opening (8a or 8b) is opened such that a pressure equalizing stream that brings about a change in pressure passes into the chamber (6a or 6b) and, as a result of the change in pressure, a turbine opening (9a or 9b) of the chamber (6a or 6b) is closed by an elastic membrane (11a or 11b), d) dedusting a filter element (7a or 7b) by means of a dedusting pulse that is applied to the filter element (7a or 7b) by the elastic membrane (11a or 11b).

12. Method according to Claim 11, characterized in that the filter element (7a or 7b) of one of the two chambers (6a or 6b) is dedusted during continued suction operation through the other chamber (6b or 6a).