Suction device with throttle valve and method for cleaning a filter in such a suction device

Abstract

The present invention relates to a suction device with a dirt collection container, a filter and a suction motor, wherein, in a suction operation of the suction device, a suction flow which flows from the dirt collection container through the filter in the direction of the suction motor is generated by means of the suction motor. The suction device is designed to perform a cleaning of the filter during continued suction operation of the suction device by generating a backflush flow R from a clean side of the filter towards a dirty side of the filter. The suction device comprises a throttle valve, wherein the throttle valve is provided on a dirty side of the filter and is designed to throttle the suction flow S so that the backflush flow R is increased by the throttling of the suction flow S. In a second aspect, the invention relates to a method for cleaning a filter in a proposed suction device, wherein filter cleaning is carried out during continued suction operation of the suction device by generating a backflush flow from a clean side of the filter towards a dirty side of the filter, wherein a throttling of the suction flow by a throttle valve leads to an increase in the backflush flow. The throttle valve can advantageously be used to adjust the cross-section of a flow channel in the suction device and / or the pressure on a dirty side of a filter of the suction device.

Description

[0001] VACUUM DEVICE WITH THROTTLE VALVE AND METHOD FOR CLEANING A FILTER IN SUCH A VACUUM DEVICE

[0002] The present invention relates to a vacuum cleaner with a dirt collection container, a filter and a suction motor, wherein during suction operation of the vacuum cleaner, a suction flow is generated by means of the suction motor, which suction flow flows from the dirt collection container through the filter in the direction of the suction motor. The vacuum cleaner is designed to clean the filter during continued suction operation of the vacuum cleaner by generating a backwash flow R from a clean side of the filter towards a dirty side of the filter. The vacuum cleaner comprises a throttle valve, wherein the throttle valve is provided on a dirty side of the filter and is designed to throttle the suction flow S, such that the backwash flow R is intensified by throttling the suction flow S.In a second aspect, the invention relates to a method for cleaning a filter in a vacuum cleaner, wherein filter cleaning is carried out during continued suction operation of the vacuum cleaner by generating a backwash flow from a clean side of the filter toward a dirty side of the filter, wherein throttling the suction flow by a throttle valve leads to an increase in the backwash flow. The throttle valve can advantageously be used to adjust the cross-section of a flow channel in the vacuum cleaner and / or the pressure on a dirty side of a filter of the vacuum cleaner.

[0003] Background of the invention:

[0004] In the field of industrial vacuum cleaners, for example, devices are known that can vacuum up both liquid and solid materials. Such vacuum cleaners are usually referred to as wet / dry vacuum cleaners. The solid materials can be, for example, dust, drilling dust, or demolition material. The liquid material can be cooling or rinse water, which, together with the solid material, can form a sludge-like mass. Typically, a vacuum cleaner is used in conjunction with a machine tool that generates dust or drilling dust. The dust-generating work carried out with the machine tool is preferably referred to as an "application" in the sense of the invention. In addition, devices are known in the field of industrial vacuum cleaners that can only vacuum up solid material.What both types of vacuum cleaners have in common is that they typically comprise a dirt collection container, a filter, a motor, and a turbine, with the turbine being driven by the motor. The air flow generated by the rotational movement of the turbine can suck in the solid and / or liquid suction material. For this purpose, the vacuum cleaner expediently comprises a suction hose, to the front end of which a nozzle or a power tool can be mounted. The dirt collection container is used to store the suctioned material until the dirt collection container is emptied. The dirt collection container can, in particular, comprise a suction opening for connecting a suction hose. The filter is designed to separate or segregate the suction material present in the air flow from the air flow. This separation of air flow and suction material is preferably referred to as "filtering" or "filtering" within the meaning of the invention.The filter is typically located between the dirt collection container and the motor. For the purposes of the invention, the side of the filter facing the dirt collection container is referred to as the first side or the dirty side of the filter, while the side of the filter facing the suction motor is referred to as the second side or the clean side of the filter. During vacuuming, the air flow typically flows from the dirt collection container toward the suction motor, i.e., from the dirty side of the filter toward the clean side.

[0005] The material sucked in by the vacuum cleaner either accumulates in the dirt collection container or becomes trapped in the vacuum cleaner's filter. A buildup of material in the filter area can lead to the formation of a solid filter cake, which can significantly increase the flow resistance created by the filter. This flow resistance slows or throttles the suction air flow used to suck in the material and can therefore disadvantageously reduce the suction power of the vacuum cleaner. To prevent such an undesirable reduction in suction power, the filters of vacuum cleaners are cleaned regularly. This cleaning of a vacuum cleaner filter is referred to as "filter cleaning" within the meaning of the invention.

[0006] Various methods for filter cleaning have been proposed in the prior art. For example, backwashing solutions are known in which the flow direction of the air stream is reversed. This causes the air stream to flow for a short time from the clean side of the filter towards the dirty side. To enable this reversal of flow direction, the pressure in the vacuum cleaner on the clean side of the filter is increased, preferably to a level that is higher than the pressure level on the dirty side of the filter. The efficiency of filter cleaning depends in particular on the pressure difference between the dirty side of the filter and the clean side of the filter. A small pressure difference between the dirty and clean sides of the vacuum cleaner filter can lead to low filter cleaning efficiency, meaning that the filter may not be cleaned optimally under certain circumstances.This can disadvantageously lead to a permanently reduced suction power of the vacuum cleaner, causing vacuuming tasks to take longer and requiring more personnel. Furthermore, the intervals at which the vacuum cleaner's filter needs to be replaced to guarantee or maintain a certain suction power can become shorter.

[0007] For example, DE 690 23 165 T2 discloses a remote control device for extraction or ventilation systems with a chamber, a driven extraction fan and at least one pipeline.

[0008] EP 3 827 724 A1 discloses a suction system comprising a central suction system, a plurality of suction points fluidically connected to the suction system, each with a throttle valve for each suction point and with a means for manually adjusting the throttle valve.

[0009] DE 20 2021 001444 U1 describes a vacuum cleaner with a tube extension that can be used as a collecting tube for catching, viewing, studying and releasing insects.

[0010] DE 10 2015 108 559 A1 discloses a backwashable air filter, in particular for a vacuum cleaner, with a filter element separating a clean air chamber from a vacuum material chamber, wherein the vacuum cleaner can be operated in a filter mode or in a backwash mode.

[0011] US 2017 151 524 A1 describes a system and method for backwashing a vacuum cleaner filter.

[0012] The object underlying the present invention is to overcome the above-described deficiencies and disadvantages of the prior art and to provide a suction device and a method for filter cleaning with which the efficiency of filter cleaning can be improved and optimized.

[0013] The object is achieved by the subject matter of the independent claims. Advantageous embodiments of the subject matter of the independent claims can be found in the dependent claims. Description of the invention:

[0014] According to the invention, a vacuum cleaner comprising a dirt collection container, a filter, and a suction motor is provided, wherein during suction operation of the vacuum cleaner, a suction flow is generated by the suction motor, which flows from the dirt collection container through the filter in the direction of the suction motor. The vacuum cleaner is designed to clean the filter during continued suction operation of the vacuum cleaner by generating a backwash flow R from a clean side of the filter towards a dirty side of the filter. The vacuum cleaner comprises a throttle valve, wherein the throttle valve is provided on a dirty side of the filter and is designed to throttle the suction flow S, such that the backwash flow R is intensified by the throttling of the suction flow S. It is particularly preferred within the meaning of the invention for the throttle valve to be arranged in the suction flow.This allows the intake flow to be adjusted and regulated, in particular throttled, by the throttle valve. For the purposes of the invention, the throttle valve is also preferably referred to as a "throttle," although the terms are preferably used synonymously.

[0015] The vacuum cleaner can comprise a vacuum head in an upper region of the vacuum cleaner and a dust collection container in a lower region of the vacuum cleaner. An inlet opening can be provided in the lower region of the vacuum cleaner, in particular in the region of the dust collection container. A suction hose can be connected to this inlet opening, wherein the suction flow S is sucked into the vacuum cleaner through the suction hose. A machine tool which generates dust during its operation can be arranged at a front end of the suction hose. This dust can be sucked away through the suction hose with the proposed vacuum cleaner. The rear side of the suction hose can open through the inlet opening into the dust collection container of the vacuum cleaner, so that the sucked-in dust-air mixture can be sucked into the dust collection container.The dirty side of the filter of the vacuum cleaner preferably faces the dust collection container, while the clean side of the filter preferably faces the upper region of the vacuum cleaner and can be oriented towards the vacuum motor. The throttle is preferably located on the dirty side of the filter and arranged in the suction flow. Advantageously, the provision of the throttle valve on the dirty side of the filter of the vacuum cleaner enables dynamic control and regulation of a filter cleaning process, wherein the filter cleaning process can be optimized by the throttle valve, particularly with regard to its duration, quality, and the time at which it takes place. In particular, the use of a throttle valve in the flow path through the vacuum cleaner enables particularly needs-based cleaning of the filter in the sense that the filter cleaning can be adapted to different applications and connected machine tools.This can be achieved, for example, by defining design points that can be controlled depending on the application or connected machine tool. In particular, the pressure conditions in the suction device can be adjusted using the throttle valve to ensure particularly efficient filter cleaning.

[0016] According to the invention, it is preferred that the cleaning process of the vacuum cleaner takes place by backwashing the filter of the vacuum cleaner. In this case, ambient air is admitted into the vacuum cleaner on the clean side of the filter, so that the pressure in the vacuum cleaner, in particular on the clean side of the filter, preferably increases suddenly. The admission of ambient air on the clean side of the filter can preferably take place through valves that close or open another inlet opening. Due to the preferably sudden increase - caused by the penetrating ambient air - the pressure on the clean side of the vacuum cleaner is briefly higher than the pressure in the dust collection container, i.e. on the dirty side of the filter of the vacuum cleaner. In this way, a backwash flow through the filter is advantageously created, whereby the backwash flow flows from the clean side towards the dirty side of the filter and thereby cleans the filter.The backwashing can in particular be maintained until similar pressure conditions prevail on the clean side of the filter and in the dust collection container, i.e. until the pressures have equalized. According to the invention, it is preferred that the ambient air entering the vacuum cleaner when the valve is opened acts directly on the filter and generates the backwash flow. However, according to the invention it can also be preferred that the incoming ambient air acts indirectly on the filter in the sense that pistons or diaphragms transfer the incoming air flow to the filter so that the filter itself does not come into contact with the incoming, unfiltered ambient air. Pistons or diaphragms can create an air cushion and push it in front of them, whereby this air cushion can generate a backwash flow which then flows through the filter from the clean side towards the dirty side and thus cleans the filter.

[0017] This cleaning process can be assisted by the provision of the throttle valve, in that the suction flow is throttled by the throttle. The throttle valve is preferably arranged in the suction flow upstream of the dust collection container and is designed to control, in particular to increase, the negative pressure in the dust collection container shortly before or during filter cleaning. The phrase "increase in the negative pressure" preferably means, within the meaning of the invention, that the pressure in the dust collection container (further) decreases. In this respect, an increase in the negative pressure within the meaning of the invention can preferably also be referred to as a pressure drop. By increasing the negative pressure, the pressure difference between the clean side of the filter on the one hand and the dust collection container on the other side can advantageously increase, so that a particularly strong backwash flow is generated through the filter of the vacuum cleaner.

[0018] The throttle valve is designed to throttle the suction flow. The term "throttle" is used in the context of the invention to mean "continuous switching". In the context of the invention, it is preferred that the throttle valve is essentially continuously switchable. In the context of the invention, this preferably means that the throttle can be not only fully open (100% opening degree) or fully closed (0% opening degree), but can preferably also assume any intermediate stage, i.e. preferably continuously variable opening degrees between 0 and 100%. The throttle can preferably not only switch binary between the settings "open" and "closed", but can also assume intermediate stages, for example to enable opening degrees of the inlet opening of the suction device of 15%, 20%, 25%, 33.3%, 43.6%, 50%, 67%, 75%, etc.The ability of the throttle valve not only to completely interrupt the suction flow or to allow it to pass through without restriction, but also to throttle it in the sense of "continuous switching" distinguishes the present invention from solutions in which the suction flow is completely interrupted.

[0019] The throttle valve or its degree of opening can preferably be controlled by a central control unit of the suction device, wherein this central control unit of the suction device is preferably designed to control the entire cleaning process.

[0020] It is preferred within the meaning of the invention that the throttle valve can be operated manually or that the throttle valve can be activated electrically. It is particularly preferred within the meaning of the invention that the entire cleaning process can be initiated manually, i.e. can be started, for example, by an operation by the user of the vacuum cleaner. Preferably, this manual start of the cleaning process can also actuate the throttle valve, so that the suction flow is briefly throttling. With such global control of the cleaning method, the throttle can be opened or closed by a central control unit as part of the cleaning process, so that separate actuation of the throttle valve is not necessary. The cleaning process can preferably be controlled by the central control unit of the vacuum cleaner.When manually actuating the throttle, the user of the vacuum cleaner closes the throttle valve, temporarily reducing the suction flow into the vacuum cleaner. Typical throttle times can range from 10 to 150 ms. Other throttle times are also possible, for example, up to 200 or 300 ms, as well as all values ​​in between.

[0021] The dirty side of the filter is preferably the side of the filter that becomes clogged with dirt and dust during vacuuming operation of the vacuum cleaner. The dirty side preferably faces the dirt collection container and the inlet opening of the vacuum cleaner. The filter of the vacuum cleaner is preferably located in a flow channel or flow path that runs from the inlet opening through the dirt collection container and through the filter towards the suction motor of the vacuum cleaner. When the suction motor is in operation, the suction flow generated by the suction motor flows through this flow channel or flow path. For this purpose, the suction motor can comprise a turbine or a compressor. By increasing the negative pressure on the dirty side of the filter of the vacuum cleaner, the pressure difference between the dirty and clean sides of the filter can advantageously be increased, thus improving the efficiency of filter cleaning.The greater pressure difference between the dirty and clean sides of the filter advantageously allows for a stronger backwash flow through the filter, allowing the filter to be backwashed by a stronger airflow and cleaned better and more efficiently. A further advantage associated with the provision of a throttle in the flow channel of a vacuum cleaner is that the filter can be cleaned while the vacuum cleaner is in continuous operation. This allows the proposed vacuum cleaner to work particularly efficiently, and any vacuuming work that needs to be done can be completed quickly and with minimal personnel expenditure. In particular, there are no unwanted work breaks during which the vacuuming operation must be interrupted due to filter cleaning.

[0022] The cleaning of the vacuum cleaner's filter can be further improved if an electrically activated and, in particular, controllable and adjustable throttle is used instead of the manually operated throttle valve. The manually operated throttle can impair the suction power during vacuuming operation if the suction flow is interrupted for too long by the throttling. If the suction flow is reduced for too long by the throttle, the negative pressure prevailing in the dust collection container during vacuuming operation can collapse too significantly, so that the negative pressure can only be restored slowly and with great effort after the filter cleaning has been completed. The electrically activated throttle valve can, in particular, be regulated and / or controlled in a highly dynamic manner, so that the amount of suction flow flowing into the vacuum cleaner through the at least one inlet opening can be adjusted as needed.In particular, by providing an adjustable, preferably electrically actuated throttle valve, the pressure on the dirt side of the suction device's filter can be adjusted. Furthermore, the cross-section of the flow channel between the inlet opening and the suction motor can be adjusted particularly precisely and as needed using an electrically actuated throttle. The advantages of the invention and the associated adjustability of the filter cleaning efficiency are that the quality of the filter cleaning is independent, for example, of the suction hose used or its diameter. Tests have shown that the filter cleaning efficiency achieved with the invention is also independent of the application or machine tool in whose context the proposed suction device with throttle valve is used.In other words, the quality of filter cleaning advantageously does not depend on the connected machine tool or the dust-generating work (“application”) performed with it; rather, the quality of filter cleaning can be adjusted using the throttle valve. This advantage is particularly achieved when an electrically activated and thus controllable throttle valve is used in the suction mode.

[0023] In particular, the throttle can be used to adjust the pressure drop in the dust collection container of the vacuum cleaner. Advantageously, the provision of the throttle can optimally resolve the conflicting objectives within the vacuuming operation, whereby a strong pressure drop is desirable on the one hand to enable efficient filter cleaning, but on the other hand can impair the suction power of the vacuum cleaner. In particular, an electrically activated throttle can enable particularly finely adjustable regulation and / or control of the suction flow or the pressure drop, so that a pressure or pressure drop on the dirt side of the vacuum cleaner's filter can be adjusted to ensure optimal cleaning of the filter in the vacuum cleaner. Tests have also shown that the throttle enables particularly good timing of the filter cleaning.In other words, the filter cleaning can be optimally timed during the operation of the vacuum cleaner, so that on the one hand optimal cleaning of the filter and on the other hand a particularly low impairment of the suction operation of the vacuum cleaner is guaranteed.

[0024] According to the invention, it is preferred that the throttle is arranged in the region of the at least one inlet opening in the region of the dirt collection container, wherein the suction flow can flow into the vacuum cleaner through the inlet opening. The inlet opening can be, for example, an opening for the suction hose. By providing the throttle valve in the region of the inlet opening of the vacuum cleaner, the invention differs from solutions in which valves or throttle valves are arranged in other regions of a vacuum cleaner or the suction hose. In the context of the present invention, the throttle is preferably arranged in the transition region from the suction hose to the vacuum cleaner. The idea underlying the invention is that the throttle is arranged in the suction flow and on the dirt side of the filter of the vacuum cleaner so that the suction flow can be throttled, i.e. preferably continuously adjusted, by the throttle.

[0025] The throttle valve can preferably also be arranged between the at least one inlet opening and the filter, so that it is arranged in particular on the dirty side of the filter of the suction device. By providing the throttle in the suction flow on the dirty side of the filter, the throttle valve can be used in particular to adjust the pressure or pressure drop on this dirty side of the filter and thus optimize the efficiency of filter cleaning by setting an optimal pressure difference between the dirty and clean sides of the filter.

[0026] The optimum pressure difference can be set in particular by the throttle valve being designed to adjust a cross-section of a flow channel in the suction device. The throttle valve can preferably be designed to adjust the cross-section of the flow channel in a range between 0 and 100%. In other words, the throttle valve can not only be used to switch binary between the positions “open” (essentially 100% opening of the inlet opening and essentially 100% opening of the flow channel) and “closed” (essentially 0% opening of the inlet opening and essentially 0% opening of the flow channel), but also to finely adjust intermediate opening degrees. This enables particularly finely adjustable and preferably stepless regulation and adjustability of the suction flow, the pressure or the pressure drop orthe pressure difference between the dirty and clean sides of the filter. For example, the throttle valve can be opened by 17%, 20%, 25%, 33.3%, 46.4%, or any other percentage between 0 and 100%.

[0027] It is preferred according to the invention that the throttle valve is designed to adjust a pressure on a dirty side of the filter of the suction device. In particular, the negative pressure on the dirty side of the filter can be increased by briefly throttling the suction flow before and / or during filter cleaning. In the sense of the invention, this preferably means that the absolute pressure on the dirty side of the filter drops or is reduced for a short time. By throttling the suction flow, the pressure on a dirty side of the filter of the suction device can advantageously be controlled or regulated. In particular, the pressure on the dirty side of the filter of the suction device can be influenced by varying or changing a flow rate through the at least one inlet opening.

[0028] In a second aspect, the invention relates to a method for cleaning a filter in a proposed vacuum cleaner. The terms, definitions, and technical advantages introduced for the vacuum cleaner preferably apply analogously to the filter cleaning method. The filter cleaning method is characterized by the following method steps: a) operating the vacuum cleaner in suction mode, b) performing filter cleaning during continued suction mode by generating a backwash flow from a clean side of the filter toward a dirty side of the filter, c) throttling a suction flow using a throttle valve to increase the backwash flow.

[0029] A significant advantage of the invention is that the filter cleaning can be performed while the vacuum cleaner continues to operate. In particular, simultaneous cleaning of at least one filter of the vacuum cleaner is possible while the vacuum cleaner continues to operate. This allows for particularly rapid and uninterrupted work with the proposed vacuum cleaner.

[0030] According to the invention, it is preferred that the throttle valve be manually operated or electrically activated. Furthermore, the cross-section of a flow channel in the suction device can be adjusted within a range between 0 and 100% by means of the throttle valve. This advantageously also makes it possible to adjust the pressure on the dirty side of a filter of the suction device using the throttle valve.

[0031] Advantageously, the proposed method enables dynamic control and regulation of the filter cleaning process, with the throttle optimizing the filter cleaning process, particularly with regard to its duration, quality, and timing. In particular, the invention enables particularly needs-based filter cleaning in the sense that the filter cleaning process can be adapted to different applications and connected machine tools. Further advantages emerge from the following description of the figures. The figures, the description, and the claims contain numerous features in combination. Those skilled in the art will expediently consider the features individually and combine them into further meaningful combinations. In the figures, identical and similar components are numbered with the same reference numerals. They show:

[0032] Fig. 1 View of a preferred embodiment of a suction device in suction mode

[0033] Fig. 2 View of a preferred embodiment of a suction device during filter cleaning

[0034] Implementation examples and figure descriptions:

[0035] Figure 1 shows a preferred embodiment of a vacuum cleaner 1 in vacuum operation. The vacuum cleaner 1 comprises a dirt collection container 2, a filter 3 and a vacuum motor 4. The vacuum motor 4 can comprise a turbine 5, wherein the turbine 5 is driven by the vacuum motor 4, so that a suction flow S is generated. Technically speaking, the turbine 5 works as a compressor, wherein air can be sucked in with the compressor in order to generate the suction flow S. The suction flow S is used to suck in dust, dirt or a liquid mixture of water and dirt. The suction flow S flows within the vacuum cleaner 1 in a flow channel or flow path, which is also designated by the reference symbol S. The vacuum cleaner 1 has an inlet opening 9, wherein the suction flow S or the flow path S is preferably formed between the inlet opening 9 and the vacuum motor 4 or the turbine 5.The inlet opening 9 is preferably arranged in the dirt collection container 2 of the vacuum cleaner 1. A filter 3 is arranged between the inlet opening 9 and the vacuum motor 4, which filter is designed to filter out dirt and dust from the suction flow S in order to prevent contamination of the vacuum motor 4. The filter 3 has a dirty side 7, which preferably faces the dirt collection container 2, and a clean side 8, which faces the vacuum motor 4 and the vacuum cleaner head. The term "dirty side 7" in the sense of the invention refers not only to the corresponding side of the filter 3, but preferably also to the region of the flow path S between the filter 3 and the inlet opening 9. The formulations "on the dirty side" and "between the filter 3 and the inlet opening 9" are preferably to be understood as synonyms in the sense of the invention.During suction operation of the vacuum cleaner 1, the suction flow S flows from the dirty side 7 toward the clean side 8 through the filter 3, with dust and dirt being filtered out of the suction flow S as it passes through the filter 3. This direction of the suction flow S from the dirty side 7 toward the clean side 8 is shown in Fig. 1 by the arrows marked with the reference symbol S.

[0036] The filter 3 can become clogged or become clogged with a filter cake during operation of the suction device 1, which can reduce the suction power of the suction device 1. In this case, it is necessary to carry out a so-called filter cleaning, i.e. cleaning the filter 3 of the suction device 1. In the context of the present invention, this filter cleaning is carried out by backflushing, i.e. a brief reversal of direction of the suction flow S. During this backflushing, the filter 3 is flowed through or rinsed with a backflushing flow R, wherein the backflushing flow R flows from the clean side 8 of the filter 3 towards its dirty side 7. The backflushing flow R is shown in Fig. 2. The backflushing flow R can be generated by opening a further inlet opening 11 of the suction device 1, wherein this further inlet opening 11 can preferably be arranged in the upper region of the suction device 1 or in the head of the suction device 1 («vacuum device head»).The additional inlet opening 11 can be opened or closed, for example, with a valve (not shown). When the valve is opened, ambient air 10 can flow into the suction device 1 through the additional inlet opening 11 and act directly or indirectly on the filter 3.

[0037] The vacuum cleaner 1 has a throttle valve 6, which is preferably arranged in the region of the inlet opening 9 in the dirt collection container 2 of the vacuum cleaner 1. The throttle valve 6 is arranged in particular in the suction flow S. With the throttle valve 6, the at least one inlet opening 9 of the vacuum cleaner 1 can be fully or partially opened or closed. In particular, the inlet opening 9 of the vacuum cleaner 1 can be continuously opened or closed, so that the suction flow S can be preferably continuously adjusted, in particular throttled, by the throttle valve 6.

[0038] During suction operation of the suction device 1, a negative pressure forms inside the suction device 1. This negative pressure is responsible for generating the suction flow S, with which dust, dirt and drilling mud can be sucked in by the suction device 1. For this purpose, the suction device 1 can be connected to a suction hose (not shown), wherein the suction hose preferably opens into the suction device 1 in the region of the inlet opening 9. In order to clean the filter 3, a pressure difference must be created between the dirty side 7 and the clean side 8 of the filter 3 in order to generate a backwash flow R. In particular, the pressure on the clean side 8 of the filter 3 is increased and reduced on the dirty side 7 of the filter 3 so that the backwash flow R can flow from the clean side 8 towards the dirty side 7 of the filter 3.The pressure reduction on the dirty side 7 of the filter 3 is achieved according to the invention in particular by reducing the cross-section of the suction flow S through the at least one inlet opening 9 in the dirt collection container 2 of the vacuum cleaner 1, so that the suction flow S itself is throttled. To throttle the suction flow S, in particular, the throttle valve 6 is used, wherein the throttle valve 6 can preferably be operated manually or activated electrically. Very particularly preferred in the context of the present invention is an electrically activated throttle which is adjustable or controllable in the sense that a flow rate of suction flow S through the inlet opening 9 can be regulated with the throttle valve 6. This makes it possible to adjust the pressure drop on the dirty side 7 of the filter 3 of the vacuum cleaner 1, as well as the pressure difference between the dirty side 7 and the clean side 8 of the filter 3, and the resulting quality of the filter cleaning.The throttle valve 6 is particularly designed to adjust a cross section Q (see Fig. 1) of the suction channel S.

[0039] The suction device 1 can have a central control unit 12 with which the process of cleaning the at least one filter 3 of the suction device 1 can be controlled. Furthermore, the suction device 1 can have a further inlet opening 11 through which ambient air 10 can flow into the suction device 1. This can generate a backwash flow R for cleaning the at least one filter 3 of the suction device 1.

[0040] List of reference symbols

[0041] 1 suction device

[0042] 2 dirt collection containers 3 filters

[0043] 4 naturally aspirated engine

[0044] 5 turbines

[0045] 6 throttle valve

[0046] 7 Dirty side

[0047] 8 Clean side

[0048] 9 Inlet opening

[0049] 10 Ambient air

[0050] 11 Inlet opening in the suction device head

[0051] 12 Central control unit S Suction flow / flow channel

[0052] Q cross-section

Claims

Patent claims 1. A suction device (1) comprising a dirt collection container (2), a filter (3) and a suction motor (4), wherein, during suction operation of the suction device (1), a suction flow S is generated by means of the suction motor (4), which flows from the dirt collection container (2) through the filter (3) towards the suction motor (4), characterized in that the suction device (1) is configured to perform a cleaning of the filter (3) during continued suction operation of the suction device (1) by generating a backwash flow R from a clean side (8) of the filter (3) towards a dirty side (7) of the filter (3), wherein the suction device (1) comprises a throttle valve (6) which is provided on a dirty side (7) of the filter (3) and is configured to throttle the suction flow S, so that the backwash flow R is intensified by throttling the suction flow S.

2. Suction device (1) according to claim 1 characterized in that the throttle valve (6) can be operated manually or can be activated electrically.

3. Suction device (1) according to one of the preceding claims characterized in that the throttle valve (6) is arranged between an inlet opening (9) of the suction device (1) and the filter (3).

4. Suction device (1) according to one of the preceding claims characterized in that the throttle valve (6) is arranged in a region of the inlet opening (9) of the suction device (1).

5. Suction device (1) according to one of the preceding claims characterized in that the throttle valve (6) is arranged in the suction flow S. A suction device (1) according to one of the preceding claims, characterized in that the throttle valve (6) is configured to adjust a cross-sectional area Q of the suction flow S in the suction device (1). A suction device (1) according to claim 6, characterized in that the throttle valve (6) is configured to adjust the cross-sectional area Q of the suction flow S in a range between 0 and 100%. A suction device (1) according to one of the preceding claims, characterized in that the throttle valve (6) is configured to adjust a pressure on a dirt side (7) of the filter (3) of the suction device (1). A suction device (1) according to one of the preceding claims, characterized in that the suction device (1) has a central control unit (12) for controlling the cleaning of the filter (3).A method for cleaning a filter (3) in a vacuum device (1) according to one of the preceding claims, characterized by the following method steps: a) operating the vacuum device (1) in suction mode, b) performing a cleaning of the filter (3) during continued suction operation by generating a backwash flow R from a clean side (8) of the filter (3) towards a dirty side (7) of the filter (3), c) throttling a suction flow S by a throttle valve (6) to intensify the backwash flow R. A method for cleaning a filter (3) according to claim 10, characterized in that the throttle valve (6) is manually actuated or the throttle valve (6) is electrically activated. A method for cleaning a filter (3) according to one of claims 10 or 11, characterized in that a cross-sectional area Q of a suction flow S in the suction device (1) is set by the throttle valve (6) in a range between 0 and 100%. A method for cleaning a filter (3) according to one of claims 10 to 12, characterized in that a pressure on the dirty side (7) of a filter (3) of the suction device (1) is applied by the Throttle valve (6) is adjusted.

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