Vacuum cleaner with two turbines and method for operating same

Abstract

The invention relates to a vacuum cleaner having a first turbine and a second turbine, the turbines being designed to generate a suction flow for introducing dust. The vacuum cleaner has a valve assembly, where the valve assembly is designated to allow a suction flow to flow through the turbines successively or in parallel. By means of the invention, the operation of the vacuum cleaner can be designed to be more variable by providing a wider characteristic suction curve of the vacuum cleaner. This is particularly possible by the fact that the turbines of the vacuum cleaner can be operated in series or in parallel and the suction characteristics of the vacuum cleaner can thus be optimally adapted to different specific applications. In addition, the present invention enables the suction operation of the vacuum cleaner to be maintained when the filter unit of the vacuum cleaner is cleaned. In a second aspect, the invention relates to a method for operating a vacuum cleaner having two turbines, where the vacuum cleaner may operate in serial or parallel operation.

Description

Technical Field

[0001] The present invention relates to a vacuum cleaner having a first turbine and a second turbine, wherein the turbines are designed to generate a suction flow for introducing dust. The vacuum cleaner has a valve assembly, wherein the valve assembly is designed to allow the suction flow to flow through the turbines sequentially or in parallel with each other. The present invention makes it possible to design a more variable operation of the vacuum cleaner by providing a wider characteristic suction curve for the vacuum cleaner. This is made possible in particular by the fact that the turbines of the vacuum cleaner can be operated in series or in parallel, and the suction characteristics of the vacuum cleaner can therefore be optimally adapted to different applications. In addition, the present invention makes it possible to maintain the suction operation of the vacuum cleaner while the filter unit of the vacuum cleaner is being cleaned. In a second aspect, the present invention relates to a method for operating a vacuum cleaner having two turbines, wherein the vacuum cleaner can be operated in series or in parallel. Background Art

[0002] It is known in the prior art that vacuum cleaners can generate a suction flow, thereby introducing dust. A turbine capable of generating a vacuum is typically used to generate the suction flow. Vacuum cleaners are used, for example, in the domestic sector to clean floors, carpets, or furniture. However, vacuum cleaners are also used on construction sites to remove dust and particles generated during machine tool operations. This can reduce the dust exposure of machine tool users and contribute significantly to user health protection.

[0003] Vacuum cleaners known from the prior art generally have the disadvantage that they are usually designed for a specific application, and the associated suction and operating characteristics cannot be varied during the service life of the vacuum cleaner. When designing a vacuum cleaner, it is often necessary to make a choice, for example, whether the vacuum cleaner should generate a high flow rate or a strong vacuum, as a combination of these different characteristics is generally not possible.

[0004] For example, EP 2 421 630 A1 discloses a vacuum cleaner with two suction units, wherein the suction units in the vacuum cleaner of EP 2 421 630 A1 are passed through in parallel by the suction flow. The disadvantage of this parallel arrangement is that it only increases the volume flow rate without increasing the pressure level.

[0005] Vacuum cleaners typically have filters or filter units that must be cleaned regularly to ensure that the suction flow can continue to flow through the filters. In many conventional vacuum cleaners, as is known from the prior art, the suction operation of the vacuum cleaner must be briefly interrupted to clean the filters or filter units. This is often accompanied by a reduction in the vacuum inside the vacuum cleaner, so that the suction flow may suddenly stop or weaken.

[0006] The object of the present invention is to overcome the drawbacks and disadvantages of the prior art described above and to provide a vacuum cleaner which optimally covers a wide range of applications and in which the suction and operating characteristics can be flexibly changed or adjusted during its operation. Another aspect of the present invention is that the suction operation of the vacuum cleaner can continue while the filter is being cleaned.

[0007] This object is achieved by the subject matter of the independent claims. Advantageous embodiments related to the subject matter of the independent claims can be found in the dependent claims. Summary of the Invention

[0008] According to the present invention, a vacuum cleaner is provided, comprising a first turbine and a second turbine, wherein the turbines are configured to generate a suction flow for introducing dust. The vacuum cleaner comprises a valve assembly, wherein the valve assembly is configured to allow the suction flow to flow through the turbines sequentially or in parallel. By providing two turbines that can operate in series or in parallel, the present invention can provide a vacuum cleaner with an extended characteristic suction curve, thereby enabling the vacuum cleaner to cover a variety of applications. In the context of the present invention, it is preferred that the switching between serial and parallel operation of the turbines occurs automatically. For example, if a vacuum limit value is exceeded or fallen below, the valve assembly of the vacuum cleaner can switch between serial and parallel operation. In other words, in the context of the present invention, it is preferred that the switching between serial and parallel operation of the vacuum cleaner occurs according to the vacuum conditions in the vacuum cleaner.

[0009] In the context of the present invention, the term "dust" is preferably used as a general term for various types of material to be extracted. For example, "dust" can include solids and / or liquids. In other words, the material to be extracted can be dry and dusty, a liquid, or a mixture of dry material to be extracted (such as dust, drilling dust, particles, and liquids), for example, water used as flushing or cooling water when working with machine tools on a construction site.

[0010] In the context of the present invention, it is preferred that the vacuum cleaner include at least one sensor for detecting operating data of the vacuum cleaner. Furthermore, the vacuum cleaner may include a control device for evaluating the operating data detected by the at least one sensor of the vacuum cleaner, wherein the control device is designed to control the vacuum cleaner based on the operating data detected by the at least one sensor. The operating data of the vacuum cleaner may specifically be the vacuum value or condition within the vacuum cleaner. However, in the context of the present invention, it is also preferred to measure motor parameters, filter parameters, particle or flow rate, and / or particle concentration, but is not limited thereto. The operating data may also preferably be referred to as operating parameters. To detect the operating parameters, in particular the vacuum conditions within the vacuum cleaner, the vacuum cleaner may include a suitable sensor system. The sensors of the sensor system may be designed, for example, to detect the vacuum in the vacuum cleaner's collection container or in different suction line sections (such as the first and second suction sections, the suction duct, and / or the first and second outlet sections). Furthermore, the vacuum cleaner can have a control device, wherein the control device is preferably designated for evaluating the vacuum data detected by the sensor system and, based on the detected vacuum data, adjusting whether the vacuum cleaner is operated in serial operation or in parallel operation. In the context of the present invention, it is preferred that the parts of the suction flow pass through the turbine of the vacuum cleaner successively in serial operation, while in parallel operation they preferably pass through the turbine of the vacuum cleaner in parallel. Due to the different operating modes of the vacuum cleaner "serial operation" and "parallel operation", the proposed vacuum cleaner is advantageously able to cover a particularly wide range of different suction outputs. This allows the vacuum cleaner or its operation to be optimally adapted to different applications, so that, for example, the energy consumption of the vacuum cleaner can also be minimized. This is particularly advantageous if the vacuum cleaner is a battery-operated vacuum cleaner, since in this case the battery life of the battery / batteries can be significantly increased or extended by the present invention.

[0011] In the context of the present invention, it is preferred that a first vacuum range and / or a first flow rate range can be assigned to the serial operation of the vacuum cleaner, and a second vacuum range and / or a second flow rate range can be assigned to the parallel operation of the vacuum cleaner. In the context of the present invention, this preferably means that the vacuum cleaner can achieve different vacuum value ranges and flow rate ranges in its different operating modes (serial operation and parallel operation). In the context of the present invention, it is preferred that these vacuum ranges and / or flow rate ranges are formed separately from each other and do not overlap. However, it is also preferred in the context of the present invention that these vacuum ranges and flow rate ranges overlap. In the context of the present invention, it is preferred that the operating parameters "flow rate" and "vacuum" can be plotted in a diagram, wherein the flow rate is preferably plotted on the y-axis and the vacuum is preferably plotted on the x-axis. Preferably, in the context of the present invention, this flow rate versus vacuum diagram can preferably be referred to as a "suction curve".

[0012] In the context of the present invention, it is preferred that serial operation of the vacuum cleaner is characterized by relatively low flow rates and high vacuum values ​​being established in the vacuum cleaner, while in parallel operation of the vacuum cleaners relatively high flow rates and low vacuum values ​​are established. It has been shown that by combining different operating modes in a vacuum cleaner, the flow rates and vacuum values ​​achievable by the vacuum cleaner can be almost doubled. The flow rates and vacuum values ​​achievable by combining different operating modes in the vacuum cleaner can advantageously be represented by a combined suction curve that actually combines the best characteristics of the individual serial operation and the individual parallel operation of the two turbines. The present invention thus makes it possible to provide a vacuum cleaner with an optimized suction curve, which is characterized in particular by particularly high achievable flow rates and vacuum values.

[0013] The same applies in a similar manner to the volume flow Q of the suction flow S. In the context of the present invention, it is preferred that a first vacuum range and / or a first volume flow range be assigned to the serial operation of the vacuum cleaner, while a second vacuum range and / or a second volume flow range be assigned to the parallel operation of the vacuum cleaner. In the context of the present invention, this preferably means that the vacuum cleaner can achieve different vacuum value ranges and volume flow ranges in its different operating modes (serial operation and parallel operation). In the context of the present invention, it is preferred that these vacuum ranges and / or volume flow ranges are formed separately from each other and do not overlap. However, for the purposes of the present invention, it is also preferred that these vacuum ranges and volume flow ranges overlap. In the context of the present invention, it is preferred that the operating parameters "volume flow" and "vacuum" can be plotted in a diagram, wherein the volume flow Q is preferably plotted on the y-axis and the vacuum is preferably plotted on the x-axis. Preferably, in the context of the present invention, this volume flow versus vacuum diagram can also preferably be referred to as a "suction curve."

[0014] In the context of the present invention, it is preferred that the serial operation of the vacuum cleaner is characterized by a relatively low volume flow Q and a high vacuum value being established in the vacuum cleaner, while the parallel operation of the vacuum cleaner is characterized by a relatively high volume flow and a low vacuum value. It has been shown that by combining different operating modes in a vacuum cleaner, the volume flow and the achievable vacuum value of the vacuum cleaner can be almost doubled. The volume flow and vacuum values ​​that can be achieved by combining different operating modes in the vacuum cleaner can advantageously be represented by a combined suction curve that actually combines the best characteristics of the individual serial operation and the individual parallel operation of the two turbines. The present invention thus makes it possible to provide a vacuum cleaner with an optimized suction curve, which is characterized in particular by particularly high achievable volume flow and vacuum values.

[0015] In the context of the present invention, it is preferred that the vacuum cleaner's turbines be designed to be relatively small and have a relatively low suction output. For example, these turbines can have approximately half the typical nominal output of a vacuum cleaner. Using two relatively small turbines, which can preferably be variably operated in parallel or in series, offers the following advantages: in particular, operating ranges characterized by high or maximum volume flows and / or high or maximum vacuum can be expanded or better served. These operating ranges are commonly used in vacuum cleaners. To ensure optimal operation of the vacuum cleaner with good suction output within these operating ranges, a very large, almost oversized turbine would have to be used. Using only one turbine would require a significant amount of space. It has been shown that using two relatively small turbines does not simply replace a single large turbine, but rather offers the aforementioned surprising advantages that industry experts would not have anticipated. In particular, using two relatively small turbines can ensure improved operation within frequently used operating ranges characterized by high volume flows and / or high vacuum.

[0016] In the context of the present invention it is preferred to use substantially identical turbines in the proposed vacuum cleaners, so that manufacturing and purchasing advantages can be achieved. However, it may also be preferred to use different turbines in order to extend the suction curve.

[0017] The feature that the valve assembly can allow the suction flow to flow through the turbines sequentially or in parallel, in the context of the present invention, preferably means that the suction flow actually always flows through the first turbine, that is, during operation of the vacuum cleaner and unless filter cleaning is taking place. If the vacuum cleaner is operated in serial operation, in the context of the present invention, it is preferred that the suction flow flows sequentially through the first and second turbines. In this embodiment of the present invention, the suction flow may first flow through the first turbine and then through the second turbine. In the context of the present invention, this sequential flow through the first and second turbines is preferably referred to as "serial operation" of the vacuum cleaner. For the purposes of the present invention, the term "serial operation" preferably means that the turbines are connected "in series" or "in series" and are passed through sequentially by the suction flow. Alternatively, the turbines may be connected in parallel and passed through in parallel. In this embodiment of the present invention, it is preferred that the suction flow is divided into a plurality of partial suction flows, wherein a first partial suction flow flows through the first turbine and a second partial suction flow flows through the second turbine. The strength, extent and / or volume of these partial suction flows preferably depends on whether the same turbine or different turbines are used.The characteristics of the mentioned partial suction flows may also depend on whether the valves of the valve assembly are fully open or only partially open.

[0018] The valve assembly may comprise, for example, a flap valve, a gate valve or a rotary valve. In the context of the present invention, it is preferred that the valve assembly comprises different types of valves, such as a flap valve and a rotary valve. However, it may also be preferred that the valve assembly comprises only flap valves, only gate valves or only rotary valves. Various potential and preferred design embodiments of the valve assembly are described below: Exemplary embodiment “Serial operation of a vacuum cleaner with a flap valve” In the context of serial operation of a vacuum cleaner with a flap valve, it is preferred within the context of the present invention that the valve assembly include flap valves, and that the vacuum cleaner's turbines are sequentially passed through by the suction flow. For example, the vacuum cleaner or its valve assembly may include two flap valves, referred to herein as a first flap valve and a second flap valve. Within the context of the present invention, the flap valves are preferably designed to open or close a pipeline for a potentially dust-laden airflow. This function of the flap valves is particularly useful when the flap valves are arranged in a continuous pipeline that needs to be opened or closed. For example, in the exemplary embodiment "Serial Operation of a Vacuum Cleaner with a Flap Valve," the second flap valve may be arranged in the second suction section between the filter unit and the second turbine. Thus, the second flap valve may be designated to open or close the second suction section between the filter unit and the second turbine. In the exemplary embodiment "Serial Operation of a Vacuum Cleaner with a Flap Valve," it is preferred within the context of the present invention that the second flap valve is closed, thereby closing the second suction section. Advantageously, therefore, no air flows from the vacuum cleaner's dust collection container toward the second turbine, but the direct path between the dust collection container and the second turbine is closed by the second flap valve of the valve assembly. In the context of the present invention, the direct path between the dust collection container and the second turbine is preferably referred to as the second suction section. Alternatively, the suction flow, preferably laden with dust, from the dust collection container flows through the vacuum cleaner's filter unit, where it is filtered so that, after passing through the filter unit, it is at least somewhat cleaned and contains significantly less dust and particles than before filtration. The preferably cleaned suction flow then flows toward the first turbine through the first suction section, preferably located between the filter unit and the first turbine. The suction flow flows through the first turbine and then enters the area of ​​the first flap valve of the vacuum cleaner's valve assembly. The first flap valve is preferably located at a T-junction, where the suction flow flows through the pipeline in the direction of the T-beam and can subsequently branch into two potential pipelines, where these two potential pipelines are released or closed by the first flap valve. On the one hand, in the exemplary embodiment “Serial operation of the vacuum cleaner with flap valves”, the suction flow emerging from the first turbine can flow in the direction of the first outlet portion and in the direction of the first inlet and outlet opening of the vacuum cleaner. However, in the exemplary embodiment “Serial operation of the vacuum cleaner with flap valves”, this path is preferably closed, in particular by the first flap valve. Alternatively, in the exemplary embodiment “Serial operation of the vacuum cleaner with flap valves” of the present invention, it is preferred that the suction flow emerging from the first turbine at the T-junction flows through the suction duct in the direction of the second turbine. Therefore, in the exemplary embodiment “Serial operation of the vacuum cleaner with flap valves”, the first flap valve is set so that the first flap valve releases the suction duct arranged between the first turbine and the second turbine for the suction flow.The suction flow then preferably flows through the second turbine, into the second outlet section, and leaves the vacuum cleaner through the second inlet and outlet openings. Therefore, in the context of the present invention, preferably, in the exemplary embodiment "Serial Operation of the Vacuum Cleaner with a Flap Valve," the first flap valve is set so that the suction flow from the first turbine can flow through the suction duct in the direction of the second turbine, while the second flap valve is set so that the second suction section between the dust collection container or filter unit and the second turbine is closed. Thus, in the exemplary embodiment "Serial Operation of the Vacuum Cleaner with a Flap Valve" of the present invention, the suction flow flows sequentially through the first turbine and then through the second turbine.

[0019] In the context of the present invention it is preferred that in the exemplary embodiment “Serial operation of the vacuum cleaner with a flap valve” both the first turbine and the second turbine are traversed by the suction flow, wherein the suction flow flows successively through the first turbine and then the second turbine.

[0020] Exemplary embodiment “Parallel operation of a vacuum cleaner with a flap valve” In the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Flap Valves," the valve assembly also includes two flap valves, with the first and second flap valves being positioned in substantially the same positions as in the exemplary embodiment "Serial Operation of Vacuum Cleaners with Flap Valves." In the context of the present invention, this preferably means that the first flap valve is positioned at the T-junction between the first turbine, on the one hand, and the pipeline leading to the first inlet and outlet openings or the second turbine, on the other hand. The second flap valve is preferably positioned in the second suction section between the dust collection container or filter unit and the second turbine. In the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Flap Valves," the first flap valve is preferably positioned so that the path from the first turbine through the first outlet section and the first inlet and outlet openings is freed. In other words, the suction flow from the first turbine can flow through the first outlet section and exit the vacuum cleaner through the first inlet and outlet openings. The second flap valve is preferably positioned so that the second suction section between the dust collection container or filter unit and the second turbine is freed, thereby allowing the suction flow from the dust collection container to at least partially flow through the second turbine. In the context of the present invention, it is preferred that in the exemplary embodiment "Parallel Operation of a Vacuum Cleaner with a Flap Valve," the suction flow is divided into preferably two partial suction flows, wherein a first partial suction flow flows through the first turbine and a second partial suction flow flows through the second turbine. The first partial suction flow leaves the vacuum cleaner through the first inlet and outlet opening, while the second partial suction flow leaves the vacuum cleaner through the second inlet and outlet opening. Therefore, in the context of the present invention, it is preferred that in the exemplary embodiment "Parallel Operation of a Vacuum Cleaner with a Flap Valve," the first flap valve is set such that the first partial suction flow from the first turbine flows through the first outlet portion in the direction of the first inlet and outlet opening, while the second flap valve is set such that the second partial suction flow from the dust collection container flows through the filter unit in the direction of the second turbine, through the second suction portion, and then continues through the second outlet portion and leaves the vacuum cleaner through the second inlet or outlet opening. Thus, in the exemplary embodiment of the present invention "Parallel Operation of Vacuum Cleaners with Flap Valves," the suction flow is divided into a first partial suction flow and a second partial suction flow, wherein these partial suction flows flow in parallel through the turbines of the vacuum cleaner. In the context of the present invention, it is preferred that the first partial suction flow flows through the first turbine and exits the vacuum cleaner via a first inlet or outlet opening, while the second partial suction flow flows through the second turbine and exits the vacuum cleaner via a second inlet or outlet opening. These partial suction flows are preferably directed through the vacuum cleaner by a valve assembly in the manner described above, wherein in the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Flap Valves," the valve assembly preferably includes two flap valves, namely, a first flap valve and a second flap valve.In the context of the present invention, it is preferred that in the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Flap Valves" both the first turbine and the second turbine are passed through by the suction flow or a portion of the suction flow, wherein the first turbine is passed through by the first portion of the suction flow and the second turbine is passed through by the second portion of the suction flow. Preferably, in the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Flap Valves" the turbines of the vacuum cleaners are passed through in parallel by the portions of the suction flow.

[0021] In the context of the present invention, it is preferred that the valve assembly comprises at least a first flap valve and a second flap valve, wherein the first flap valve is arranged behind the first turbine in the direction of the suction flow, and wherein the second flap valve is arranged in front of the second turbine in the direction of the suction flow. Preferably, the first flap valve can be arranged in the region of a T-junction between the first turbine on the one hand and the first outlet section and the first inlet or outlet opening, or the suction duct and the second turbine on the other hand. In the context of the present invention, it is preferred that the first flap valve allows the suction flow to flow in the direction of the first inlet or outlet opening or in the direction of the second turbine, while the second flap valve enables the suction flow to flow through the second turbine or prevents such flow. In this case, the second flap valve is designated to release or close the second suction section between the dust collection container or filter unit on the one hand and the second turbine on the other hand.

[0022] Of course, gate valves can also be used instead of flap valves.

[0023] Example embodiment "Serial operation of a vacuum cleaner having a rotary valve" In an exemplary embodiment of the present invention in which the valve assembly comprises rotary valves, the valve assembly preferably comprises three rotary valves, wherein the first rotary valve is located between the first and second turbines, and the second rotary valve is located between the second turbine and the filter unit. In the context of the present invention, it is preferred that the first rotary valve be configured to close or release the suction duct between the first and second turbines, while the second rotary valve be configured to close or release the second suction section between the second turbine and the filter unit. In the exemplary embodiment "Serial Operation of a Vacuum Cleaner with Rotary Valves," the first rotary valve is preferably configured to release the suction duct between the first and second turbines. This allows the preferably undivided suction flow from the first turbine to flow through the suction duct toward the second turbine. The second rotary valve is preferably located in the second suction section, wherein in the exemplary embodiment "Serial Operation of a Vacuum Cleaner with Rotary Valves," the second rotary valve is configured to close the second suction section. As a result, no air can flow from the dust collection container or the filter unit toward the second turbine. The suction flow thus advantageously flows undivided from the dust collection container in the direction of the first turbine of the vacuum cleaner through the filter unit and through the first suction section.

[0024] In the context of the present invention, it is preferred that, in exemplary embodiments of the present invention in which the valve assembly comprises a rotary valve, the valve assembly includes a third rotary valve, wherein the third rotary valve is disposed between the first turbine and the first inlet or outlet opening. Preferably, the third rotary valve can be configured to close or release the outlet section between the first turbine and the first inlet or outlet opening. In the exemplary embodiment "Serial Operation of a Vacuum Cleaner with a Rotary Valve," the third rotary valve is preferably configured so that it closes the first outlet section, thereby preventing airflow from the first turbine from flowing toward the first inlet and outlet openings. Alternatively, after the suction flow has passed through the second turbine, it preferably exits the vacuum cleaner through the second inlet or outlet opening. Therefore, in the exemplary embodiment "Serial Operation of a Vacuum Cleaner with a Rotary Valve," it is preferred that the first rotary valve of the valve assembly opens and releases the suction line between the first and second turbines, while the second and third rotary valves of the valve assembly are closed, and their corresponding line sections (the second suction section and the first outlet section) are blocked. In particular, in the exemplary embodiment "Serial Operation of a Vacuum Cleaner with a Rotary Valve," the turbines of the vacuum cleaner are passed through serially (i.e., one after the other), i.e., the suction flow first flows through the first turbine and then through the second turbine. In this case, the preferably undivided suction flow from the valve assembly or its rotary valve is correspondingly directed through the vacuum cleaner.

[0025] Exemplary embodiment “Parallel operation of a vacuum cleaner having a rotary valve” In the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Rotary Valves," it is preferred that the first rotary valve of the valve assembly be closed, closing the suction duct between the first and second turbines, while the second and third rotary valves of the valve assembly are opened, releasing their corresponding duct sections (the second suction section and the first outlet section). Opening the second rotary valve, preferably located in the second suction section between the dust collection container or filter unit and the second turbine, allows the suction flow to be split, with a first portion of the suction flow from the dust collection container flowing through the first turbine and a second portion of the suction flow from the dust collection container flowing through the second turbine. Once the first portion of the suction flow has passed through the first turbine, it flows into the first outlet section and exits the vacuum cleaner through the first inlet or outlet opening. In the exemplary embodiment "Parallel Operation of Vacuum Cleaners with Rotary Valves," the first outlet section is preferably released by the third rotary valve. The second portion of the suction flow flows from the dust collection container toward the second turbine, through the filter unit and the second suction section, and further through the second outlet section, allowing the second portion of the suction flow to exit the vacuum cleaner through the second inlet or outlet opening.

[0026] In the context of the present invention, it is preferred that, in the configuration of the valve assembly with rotary valves, the function of the first flap valve is assumed by the first and third rotary valves, while the function of the second flap valve substantially corresponds to that of the second rotary valve.

[0027] In the context of the present invention, it is preferred that the vacuum cleaner include a dust collection container for collecting dust. This dust collection container can preferably be arranged in the lower region of the vacuum cleaner and collect dust and particles generated during operation with the machine tool. A filter unit of the vacuum cleaner can be arranged above the dust collection container so that dust filtered from the suction flow by the filter unit and filter cake released from the filter during filter cleaning can fall into the dust collection container.

[0028] In the context of the present invention, it is preferred that the first turbine is assigned a first inlet or outlet opening and the second turbine is assigned a second inlet or outlet opening. Preferably, the suction flow can leave the vacuum cleaner through the first inlet or outlet opening and / or the second inlet or outlet opening. In this case, the preferably undivided suction flow can leave the vacuum cleaner through the second inlet or outlet opening in serial operation, while the partial suction flow generated during the parallel flow through the vacuum cleaner's turbines leaves the vacuum cleaner through the first inlet or outlet opening and the second inlet or outlet opening. In the context of the present invention, it is preferred that the first outlet section is arranged between the first turbine and the first inlet or outlet opening, and the second outlet section is arranged between the second turbine and the second inlet or outlet opening. In the context of the present invention, it is preferred that the first turbine and the first inlet or outlet opening are connected to each other via the first outlet section, and the second turbine and the second inlet or outlet opening are connected to each other via the second outlet section.

[0029] In the context of the present invention, it is preferred that the valve assembly is designed to allow a cleaning flow to flow through the first turbine and / or the second turbine in a direction opposite to the suction flow. The filter unit of the vacuum cleaner can be cleaned by the cleaning flow, which preferably flows in a direction opposite to the suction flow. This ensures optimal, efficient suction operation of the vacuum cleaner throughout the life of the vacuum cleaner. The vacuum cleaner can be operated in a suction mode, in which the suction flow can flow through both turbines of the vacuum cleaner (parallel operation), or in which the suction flow can flow through one of the two turbines of the vacuum cleaner (serial operation). In addition, the vacuum cleaner can be operated in a cleaning mode, in which the filter unit, preferably one of the two filter parts of the filter unit, is cleaned.

[0030] In the context of the present invention, it is preferred that the vacuum cleaner includes a filter unit for filtering the suction flow, wherein, when cleaning the filter unit of the vacuum cleaner, one turbine maintains the suction operation of the vacuum cleaner, while the other turbine is passed through by the cleaning flow. The flow direction of the cleaning flow is preferably opposite to the flow direction of the suction flow. The suction flow of the vacuum cleaner can preferably extend from the suction hose inlet through the dust collection container, through the filter unit, through one or both suction ducts and through one or both of the turbines, wherein the suction flow leaves the vacuum cleaner through one or both of the inlet or outlet openings of the vacuum cleaner. In other words, the suction flow can enter the vacuum cleaner in the area of ​​the suction hose inlet, flow through the dust collection container, the filter unit, one or both suction ducts and flow through one or both of the turbines, and leave the vacuum cleaner through one or both of the inlet or outlet openings of the vacuum cleaner. The cleaning flow preferably flows in a flow direction opposite to the flow direction of the suction flow. The clean flow can also be referred to as a backwash flow because it flows through the vacuum cleaner's turbine and / or filter unit in the opposite direction of the suction flow. The clean flow can preferably be initiated by opening at least one of the vacuum cleaner's inlet or outlet openings. This can be achieved, for example, by releasing at least one of these outlet sections via a valve assembly, allowing ambient air to be introduced into the vacuum cleaner through the corresponding inlet or outlet opening. The suction process for generating the clean flow is preferably performed abruptly, wherein the clean flow is particularly caused by the prevailing vacuum in the vacuum cleaner. When the valve assembly is switched so that at least one of these inlet or outlet openings is released, a flow is generated to compensate for the pressure between the environment and the interior of the vacuum cleaner. This pressure-compensating flow preferably forms the clean flow in the context of the present invention. Preferably, the clean flow from the inlet or outlet opening flows through the first or second outlet section, the first or second turbine, and the first or second suction duct toward the filter unit. The clean flow ensures backwashing or flushing of the filter unit, thereby releasing filter cake that may have adhered to the filter unit. Cleaning of the filter can advantageously be achieved by backwashing or flushing the filter unit, and the detached filter cake can fall into the dust collection container of the vacuum cleaner for subsequent disposal.

[0031] The present invention now makes it possible to generate a cleaning flow that can flow through the first turbine or the second turbine when cleaning the filter unit, preferably in the opposite direction to the suction flow that flows through the turbine during suction operation of the vacuum cleaner. In the context of the present invention, it is preferred that the cleaning flow is caused by a pressure difference between the interior of the vacuum cleaner and its surroundings. Preferably, a flow is generated to compensate for this pressure difference, and this pressure-compensating flow preferably forms a cleaning flow with which the filter unit or its filter section can be backwashed or flushed, thereby cleaning it.

[0032] The cleaning flow can be influenced, in particular, by cleverly switching or positioning the valve assembly. In the context of the present invention, it is preferred that the filter unit have a first filter section and a second filter section, wherein the first filter section is assigned a first cleaning zone and the second filter section is assigned a second cleaning zone. Preferably, the cleaning flow can flow through the first turbine when cleaning the first filter section, while the cleaning flow flows through the first turbine when cleaning the second filter section. When cleaning the first filter section, it is preferred in the context of the present invention that the cleaning flow flows through the vacuum cleaner's first turbine, while the suction flow flows through the second turbine, thereby maintaining suction operation through the second turbine. Similarly, when cleaning the second filter section, the cleaning flow can flow through the vacuum cleaner's second turbine, while the suction flow flows through the first turbine, thereby maintaining suction operation through the first turbine. In this way, the present invention allows the vacuum cleaner to perform continuous suction operation while simultaneously cleaning the filter unit or a portion of the filter unit.

[0033] In the context of the present invention, it is preferred that the clean areas are fluidically separated from one another so that, in particular, no fluid exchange or pressure compensation occurs between the clean areas. The clean area preferably refers to the space on or above the clean side of the filter unit (i.e., the side of the filter that faces the turbine rather than the dust collection container in a spatial sense).

[0034] In the context of the present invention, it is preferred that the valve assembly include a fourth rotary valve, wherein the fourth rotary valve is positioned between the first turbine and the filter unit and is designated to close or release the first suction section between the first turbine and the filter unit. For example, if the valve assembly of a vacuum cleaner includes four rotary valves, the first rotary valve, preferably located in the suction duct between the first and second turbines, can be closed to allow cleaning of the first filter section. This prevents the vacuum cleaner's turbines from operating in series, and suction flow cannot flow through the vacuum cleaner's two turbines in sequence. The second, third, and fourth rotary valves can be opened to enable cleaning of the first filter section. By opening the second rotary valve, preferably located in the second suction section between the filter unit and the second turbine, a portion of the suction flow from the vacuum cleaner's dust collection container can flow through the second suction section toward the second turbine, thereby maintaining suction operation by the second turbine. The suction flow can then flow through the second outlet section and exit the vacuum cleaner through the second inlet or outlet opening. By opening the third rotary valve, preferably located in the first outlet section, the first outlet section can be released and the first inlet or outlet opening can be opened. As a result, ambient air can be introduced into the vacuum cleaner, this introduction of ambient air being caused in particular by a pressure difference prevailing between the interior of the vacuum cleaner, where vacuum pressure exists, and the environment of the vacuum cleaner, which is at normal pressure or atmospheric pressure.

[0035] In particular, ambient air can be introduced suddenly, the more suddenly the introduction occurs, the greater the pressure difference between the interior of the vacuum cleaner and the environment. The sucked-in ambient air forms a clean flow, which, in the exemplary embodiment described here, flows from a first inlet or outlet opening through a first turbine in the direction of a first filter part, wherein the first filter part is cleaned and the suction operation is maintained by a second turbine. The clean flow flows through the first filter part in a direction opposite to the flow direction of the suction flow, and thus, in the context of the present invention, this is preferably referred to as flushing or backwashing of the first filter part. The clean flow emerging from the first turbine reaches the filter unit, in particular due to the opening of the fourth rotary valve. Opening the fourth rotary valve of the valve assembly of the vacuum cleaner allows the first suction part to be released, so that the clean flow can flow from the first turbine in the direction of the filter unit.

[0036] In a manner similar to that described above, in the second filter cleaning mode, the second filter section can be cleaned, and suction operation can be maintained by the first turbine. Also in this second filter cleaning mode, the first rotary valve is preferably closed, while the second, third, and fourth rotary valves are open. In the second filter cleaning mode, ambient air flows into the vacuum cleaner through the second inlet or outlet opening, where this inflow of ambient air forms a cleaning flow for the second turbine. This cleaning flow flows through the second turbine toward the filter unit, specifically toward the second filter section of the filter unit. Because the second rotary valve is open in the second filter cleaning mode, the cleaning flow can reach the filter unit and rinse the second filter section, thereby cleaning it. The vacuum cleaner's suction operation is maintained by the first turbine, with the suction flow entering the vacuum cleaner through the suction hose inlet, into the vacuum cleaner's dust collection container, and then passing through the filter unit, the open fourth rotary valve, and the first suction section to reach the first turbine. From there, the suction flow continues toward the first inlet or outlet opening, where it passes through the third rotary valve and the first outlet section.

[0037] In the context of the present invention, it is preferred that the vacuum cleaner's suction operation be maintained while the first filter section of the filter unit is being cleaned because the suction flow continues to flow through the second turbine. While the second filter section is being cleaned and the cleaning flow is flowing through the second turbine, the vacuum cleaner's suction operation can be maintained by the suction flow continuing to flow through the first turbine. This allows one turbine to maintain suction operation while the filter section assigned to another turbine and another cleaning area can be cleaned.

[0038] If the filter unit consists of two filter parts, each of which is assigned to a first turbine and a second turbine, the strength, range, and / or volume of these partial suction flows can preferably also depend on the degree of free flow or blockage of these filter parts. For example, if the first filter part assigned to the first turbine has been freshly cleaned and is relatively new, a strong and large partial suction flow can flow through the first filter part, while a clogged or old filter part can only allow a weaker or smaller partial suction flow to pass. The filter unit can have a second filter part, which can be assigned to the second turbine. These filter parts can be formed, for example, such that the filter unit includes a first filter, which can be referred to as the first filter part, and the filter unit includes a second filter, which can be referred to as the second filter part. Alternatively, the filter unit can also include a single filter, which includes independent filter parts. In the context of the present invention, it is preferred that if a first filter part and a second filter part are provided, these filter parts can be assigned to corresponding cleaning areas. Preferably, the first filter portion of the filter unit can be assigned to the first cleaning zone, and the second filter portion of the filter unit can be assigned to the second cleaning zone.

[0039] In a second aspect, the present invention relates to a method for operating the proposed vacuum cleaner, wherein the method comprises the following process steps: a) providing a vacuum cleaner having a first turbine and a second turbine, b) Controlling the valve assembly of the vacuum cleaner so that the suction flow flows through the turbines sequentially or in parallel.

[0040] The terms, definitions, and technical advantages described above for the vacuum cleaner preferably apply in a similar manner to the operating method. Preferably, the proposed method may include detecting and / or evaluating operating data of the vacuum cleaner, wherein the control of the valve assembly of the vacuum cleaner is performed based on the previously detected operating data. In the context of the present invention, it is preferred to provide a vacuum cleaner having two relatively small turbines, wherein the turbines may be substantially identical or different. When the vacuum cleaner is operated, the operating data and / or operating parameters may be detected by a suitable sensor system of the vacuum cleaner. The vacuum cleaner may include a control device by which the operating data and / or operating parameters detected by the sensor system may be evaluated. The detected and / or evaluated operating data and / or operating parameters may preferably be used to control the vacuum cleaner or its valve assembly by setting a specific operating mode. The operating modes of the vacuum cleaner may specifically include serial and parallel operation of the vacuum cleaner's turbines. In serial operation of the vacuum cleaner, the suction flow may flow sequentially through the first turbine and the second turbine as a substantially undivided suction flow. In parallel operation of the vacuum cleaner, the suction flow is preferably divided and in each case one partial suction flow flows through the first turbine and the second turbine. In the context of the present invention, it is preferred that in parallel operation, a first partial suction flow flows through the first turbine and a second partial suction flow flows through the second turbine.

[0041] Further advantages can be found in the following description of the drawings. The drawings, the description, and the claims contain many combined features. A person skilled in the art will also advantageously consider these features individually and combine them into advantageous further combinations. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In the accompanying drawings, the same and equivalent parts are numbered with the same reference numerals. In the accompanying drawings: Figure 1 A view showing a preferred design embodiment of a vacuum cleaner having a valve assembly and two turbines Figure 2 A view showing a preferred design embodiment of a vacuum cleaner in serial operation with a rotary valve Figure 3 A view showing a preferred design embodiment of a vacuum cleaner in serial operation with a flap valve Figure 4 A view showing a preferred design embodiment of a vacuum cleaner with a rotary valve in parallel operation Figure 5 A view showing a preferred design embodiment of a vacuum cleaner with flap valves in parallel operation Figure 6 A diagram showing a preferred design embodiment of a combined puff curve Figure 7 Another view showing a preferred design embodiment of a combined puff curve Figure 8 A view showing a preferred design embodiment of a vacuum cleaner with a filter cleaning function Figure 9 A view showing a preferred design embodiment of a vacuum cleaner with filter cleaning and backwashing via a first turbine Figure 10 A view showing a preferred design embodiment of a vacuum cleaner with filter cleaning and backwashing via a second turbine Figure 11 A view showing an alternative preferred design embodiment of a vacuum cleaner with filter cleaning functionality Figure 12 A view showing an alternative preferred design embodiment of a vacuum cleaner with filter cleaning and backwashing via a first turbine Figure 13 A view showing an alternative preferred design embodiment of a vacuum cleaner with filter cleaning and backwashing via a second turbine DETAILED DESCRIPTION

[0043] Figure 1 A preferred embodiment of a vacuum cleaner 10 is shown, which has a first turbine T1 and a second turbine T2, as well as a valve assembly V. The vacuum cleaner 10 includes a dust collection container 12 in its lower area, to which a suction hose inlet 14 can be connected. For example, a suction hose (not shown) can be connected to the suction hose inlet 14 to connect the vacuum cleaner 10 to a machine tool (not shown) or a floor nozzle (not shown). A filter unit F can be positioned above the dust collection container 12, through which the airflow passing through the vacuum cleaner 10 is drawn. The airflow through the vacuum cleaner 10 can be generated by the two turbines T1 and T2. The airflow (preferably a dust-laden airflow eLS) enters the vacuum cleaner 10 through the suction hose inlet 14 and is directed toward the first turbine T1 and the second turbine T2. This flow is preferably referred to as the suction flow S. The suction flow S can be cleaned as it passes through the filter unit F. In the context of the present invention, the suction flow S can flow essentially undivided successively through the two turbines T1 , T2 of the vacuum cleaner 10 (serial operation SM, see Figure 2 and Figure 3 ), or is divided into a first partial suction flow TS1 and a second partial suction flow TS2 and flows in parallel through the turbines T1 , T2 (parallel operation PM, see Figure 4 and Figure 5 ).

[0044] The suction flow S is guided through the interior of the vacuum cleaner 10 by means of a valve assembly V. The valve assembly V may comprise a flap valve KV and / or a rotary valve DV, wherein those valve assemblies V having only a flap valve KV or only a rotary valve DV, as well as those valve assemblies V having both a flap valve KV and a rotary valve DV may be preferred. Figure 1 and Figure 2 In FIG, a valve assembly V including a rotary valve DV is shown by way of example. Figure 1 In FIG, the different positions of the rotary valve DV or the rotatability of the rotary valve DV are indicated by curved double arrows, respectively.

[0045] The areas adjacent to the filter unit F in the direction of the suction flow S are preferably referred to herein as the first suction section SA1 and the second suction section SA2. The first suction section SA1 is preferably located between the filter unit F and the first turbine T1, while the second suction section SA2 is preferably located between the filter unit F and the second turbine T2. In the context of the present invention, the area between the turbines T1 and T2 is preferably referred to as the suction duct SK. Pipeline sections, referred to as the first outlet section AA1 and the second outlet section AA2, adjoin the turbines T1 and T2 in the direction of the suction flow S. The first outlet section AA1 is preferably located between the first turbine T1 and the first inlet or outlet opening O1, while the second outlet section AA2 is preferably located between the second turbine T2 and the second inlet or outlet opening O2. The suction flow S can exit the vacuum cleaner 10 as an outflow air flow aLS through the inlet or outlet openings O1 and O2.

[0046] exist Figure 1In the exemplary embodiment of the present invention shown, the rotary valve DV of the valve assembly V is disposed in the suction duct SK, in the second suction section SA2, and in the first outlet section AA1. When the suction flow S passes through the turbines T1 and T2 successively, the first rotary valve DV1 is located in the suction duct SK, after the first turbine T1 and before the second turbine T2 in the direction of the suction flow S. The first rotary valve DV1 is preferably designed to open or close the suction duct SK. As a result, the rotary valve DV1 determines whether the suction flow S, after passing through the first turbine T1, continues to flow toward the second turbine T2 (in serial operation SM of the vacuum cleaner 10) or toward the first inlet or outlet opening O1, where it can exit the vacuum cleaner 10 as an outflow airflow aLS. The second rotary valve DV2 is preferably located between the filter unit F and the second turbine T2 in the direction of the suction flow S, and therefore in the second suction section SA2. Thus, the second rotary valve DV2 determines whether a portion of the suction flow S flows from the dust collection container 12 toward the second turbine T2 (parallel operation PM of the vacuum cleaner 10), or whether the suction flow S flows substantially undivided through the first suction portion SA1 toward the first turbine T1. In the context of the present invention, the portion of the suction flow S that flows through the second turbine T2 is preferably referred to as the second partial suction flow TS2, while the portion of the suction flow S that flows through the first turbine T1 is preferably referred to as the first partial suction flow TS1. The third rotary valve DV3 is located after the first turbine T1 in the direction of the suction flow S, but within the first suction portion SA1, preferably between the first turbine T1 and the first inlet or outlet opening O1. Therefore, the third rotary valve DV3 determines whether the first inlet or outlet opening O1 is opened or closed. In other words, the third rotary valve DV3 is designated to release or close the first outlet portion AA1 or the first inlet or outlet opening O1. In the open condition, the suction flow S can completely or partially leave the vacuum cleaner 10 as an outflow air flow aLS through the first inlet or outlet opening O1 .

[0047] A second outlet portion AA2 is arranged behind the second turbine T2 in the direction of the suction flow S, said second outlet portion AA2 forming a line portion between the second turbine T2 and the second inlet or outlet opening O2. When the vacuum cleaner 10 is operated in parallel operation PM, a portion of the suction flow S, in particular the second partial suction flow TS2, can leave the vacuum cleaner 10 as an outflow airflow aLS through the second inlet or outlet opening O2.

[0048] Figure 2The preferred embodiment of the vacuum cleaner 10 is shown in serial operation SM. The vacuum cleaner has a valve assembly V comprising three rotary valves DV. The position and function of the three rotary valves DV are described in the previous paragraph. In serial operation SM of the vacuum cleaner 10, the suction flow S flows sequentially through the first turbine T1 and the second turbine T2 substantially undivided. The flow of the suction flow S is Figure 2 Indicated by a dotted arrow in FIG. 1 . To achieve serial operation SM of the vacuum cleaner 10, the first rotary valve DV1 in the suction duct SK between the turbines T1 and T2 is opened, while the second rotary valve DV2 and the third rotary valve DV3 are closed. After passing through the first turbine T1, the suction flow S flows through the suction duct SK released by the first rotary valve DV1 in the direction of the second turbine T2. After passing through the second turbine T2, the suction flow S further flows through the second outlet portion AA2 and leaves the vacuum cleaner 10 as an outflow airflow aLS through the second inlet or outlet opening O2. If the valve assembly V (e.g. Figure 2 ) is formed by three rotary valves DV, the first outlet portion AA1 and the second suction portion SA2 are closed in the serial operation SM of the vacuum cleaner 10 because the second rotary valve DV2 and the third rotary valve DV3 are closed.

[0049] exist Figure 2 The suction curve is shown in the lower area of ​​. In the case of the suction curve, the volume flow Q of the suction flow S can be displayed on the y-axis and the vacuum-p can be displayed on the x-axis. For example, the volume flow Q of the suction flow S can be expressed in units of meters 3 / second (m 3 / s), while vacuum -p can be specified in millibars (mbar). Although vacuum has a negative algebraic sign, along Figure 2 The positive x-axis in the illustrated pumping curves has the vacuum removed; therefore, the magnitude of vacuum-p is represented. Figure 2 The suction curve in FIG. 1 specifically shows the volume flow Q compared to the vacuum value when only the first turbine T1 ("T1") of the vacuum cleaner 10 is used. Furthermore, the volume flow Q is shown as a function of the vacuum value when the suction flow S passes through the first turbine T1 and the second turbine T2 successively in serial operation SM (or "in serial") ("T(1 + 2)_S"). It can be seen that significantly higher vacuum values ​​can be achieved if both turbines T1, T2 are used, i.e., if the vacuum cleaner 10 has two turbines T1, T2 and the suction flow S passes through them successively.

[0050] Figure 3A preferred design embodiment of a vacuum cleaner 10 is shown in serial operation SM, the vacuum cleaner having a valve assembly V, which comprises two flap valves KV. The first flap valve KV1 can be arranged and / or adjusted so that the first flap valve KV1 is arranged behind the first turbine T1 in the direction of the suction flow S. The first flap valve KV1 can release the suction duct SK in the direction of the second turbine T2 or release the first outlet portion AA1 in the direction of the first inlet or outlet opening O1. The second flap valve KV2 is arranged in the second suction portion SA2 between the filter unit F and the second turbine T2, so that the second flap valve can release or close the second suction portion SA2. In the embodiment of the vacuum cleaner 10 with the flap valve KV Figure 3 In the serial operation SM shown, the first flap valve KV1 is set so that the suction flow S from the first turbine T1 can flow through the suction duct SK in the direction of the second turbine T2. The second flap valve KV2 is closed so that the air flow from the dust collection container 12 cannot flow through the second suction portion SA2 in the direction of the second turbine T2. In this exemplary embodiment of the invention, the first flap valve KV1 actually takes over the functions of the first rotary valve DV1 and the third rotary valve D3, as shown in Figure 2 As shown and described in .

[0051] The corresponding suction curve of the serial operation SM of the vacuum cleaner 10 with the flap valve KV corresponds substantially to the suction curve of the serial operation SM of the vacuum cleaner 10 with the rotary valve DV. By means of the valve assembly V comprising the flap valve KV, almost twice the vacuum value -p can be achieved.

[0052] Figure 4 A preferred design embodiment of a vacuum cleaner 10 in parallel operation PM with rotary valves DV is shown. The three rotary valves DV are again located in known positions, i.e. the first rotary valve DV1 in the suction duct SK between the turbines T1, T2, the second rotary valve DV2 in the second suction section SA2 and the third rotary valve DV3 in the first outlet section AA1. Figure 4In the embodiment of the vacuum cleaner 10 shown, in parallel operation PM with a rotary valve DV, the suction flow S in the dust collecting container 12 is divided into two partial suction flows TS1, TS2. The first partial suction flow TS1 flows from the dust collecting container 12 through the filter unit F, through the first suction section SA1, through the first turbine T1, through the open third rotary valve DV3 and through the first outlet section AA1, and leaves the vacuum cleaner 10 as an outflow air flow aLS through the first inlet or outlet opening O1. The second partial suction flow TS2 flows from the dust collecting container 12 through the filter unit F, through the open second rotary valve DV2 and the second suction section SA2, through the second turbine T2 and through the second outlet section AA2, and leaves the vacuum cleaner 10 as an outflow air flow aLS through the second inlet or outlet opening O2. Therefore, in Figure 4 The position of the rotary valve DV of the valve assembly V in the embodiment of the invention shown is exactly represented in FIG. Figure 2 The forward mapping of the position of the rotary valve DV of the valve assembly V in the exemplary embodiment of the present invention is shown. Figure 2 In the embodiment of FIG. 1 , the first rotary valve DV1 is open and the second rotary valve DV2 and the third rotary valve DV3 are closed, but in FIG. Figure 4 In the embodiment of FIG. 5 , the first rotary valve DV1 in the suction duct SK is closed, whereas the second rotary valve DV2 in the second suction portion SA2 and the third rotary valve DV3 in the first outlet portion AA1 are open.

[0053] exist Figure 4 The lower area of ​​the diagram shows a suction curve showing the volume flow Q as a function of the vacuum p in parallel operation PM of the vacuum cleaner 10. The volume flow Q as a function of the vacuum p when only one turbine is used is labeled "T1" in the suction curve, while the volume flow Q as a function of the vacuum p when turbines T1 and T2 are operated PM in parallel is labeled "T(1 + 2)_P." It can be clearly seen that when using two turbines T1 and T2 in parallel operation PM, a volume flow Q almost twice as high as when the vacuum cleaner 10 is operated with only one turbine ("T1") can be achieved.

[0054] Figure 5 FIG. 1 shows a preferred design embodiment of a vacuum cleaner 10 in parallel operation PM, which has a valve assembly V comprising two flap valves KV. The flap valves KV are as follows: Figure 3This means that the first flap valve KV1 is arranged in the region of the T-junction, behind the first turbine T1 in the direction of the suction flow S, while the second flap valve KV2 is arranged in the second suction section SA2 between the filter unit F and the second turbine T2. Figure 5 In the exemplary embodiment of the invention shown, the first flap valve KV1 is adjusted such that the first partial suction flow TS1 flows through the first outlet portion AA1 and can leave the vacuum cleaner 10 as outflow air flow aLS through the first inlet or outlet opening O1. Figure 5 In the exemplary embodiment of the invention shown, the second flap valve KV2 is adjusted such that the second suction portion SA2 is open and the second partial suction flow TS2 can flow from the dust collecting container 12 in the direction of the second turbine T2 .

[0055] The corresponding suction curve of the parallel operation PM of the vacuum cleaners 10 with flap valves KV corresponds substantially to the suction curve of the parallel operation PM of the vacuum cleaners 10 with rotary valves DV. Also by means of the valve assembly V comprising the flap valves KV, the volume flow Q can be almost doubled.

[0056] Figure 6 It is shown how a combined suction curve, or a suction curve of the proposed vacuum cleaner 10, is obtained as a combination of the aforementioned suction curves by operating the vacuum cleaner 10 in serial operation SM or in parallel operation PM. The invention is based on the idea that the operation of the vacuum cleaner 10 can be switched from a first operating mode, for example the operating mode parallel operation PM, to a second operating mode, for example the operating mode serial operation SM, depending on the detected vacuum value -p. The switching preferably takes place at a switching point SP, which in the context of the present invention can preferably also be referred to as a "vacuum-triggered switching point SP". For example, the vacuum cleaner 10 can be operated in the operating mode parallel operation PM at low vacuum values ​​and in the operating mode serial operation SM at higher vacuum values. Figure 6 In FIG, different curves of the volume flow Q are plotted against the vacuum p. For example, the curve of the volume flow Q for the operation of a vacuum cleaner with a turbine is shown, which exists, for example, when the proposed vacuum cleaner 10 is operated with only one turbine T (for example, the first turbine T1). This curve is shown in FIG. Figure 6, marked "T1". Also shown are the curves for volume flow Q versus vacuum value -p for parallel operation ("T(1 + 2)_P") and serial operation ("T(1 + 2)_S"). The operation of the vacuum cleaner 10 can now be optimized because, for low vacuum values ​​-p, the vacuum cleaner 10 operates in parallel operation PM, while at higher vacuum values ​​-p, the vacuum cleaner 10 operates in serial operation SM. In between, a switch occurs between the operating modes of parallel operation PM ("first operating mode") and serial operation SM ("second operating mode"). This switch preferably occurs at a switching point SP, which is characterized by the switching vacuum value -p(SP).

[0057] To detect the vacuum value -p, the vacuum cleaner 10 may have a suitable sensor system (not shown). Furthermore, the vacuum cleaner 10 may comprise a control device (not shown) which is designated for controlling the vacuum cleaner 10 or causing a switch between operating modes of the vacuum cleaner 10 .

[0058] Figure 7 Possible combined suction curves in "pure form" are shown, where the abbreviation "PM" denotes the suction curve range in which the vacuum cleaner 10 is operated in parallel operation PM (on the x-axis: "first vacuum range", UB1), and the abbreviation "SM" denotes the suction curve range in which the vacuum cleaner 10 is operated in serial operation SM (on the x-axis: "second vacuum range", UB2).

[0059] Figure 8 A preferred design embodiment of a vacuum cleaner 10 with filter cleaning functionality is shown. Figure 8 Basically corresponds to Figure 1 , among which Figure 8 An additional rotary valve DV4 is shown, and the filter unit F is divided into two parts. Figure 8The filter unit F of the illustrated embodiment of the vacuum cleaner 10 may include a first filter section FA1 and a second filter section FA2, wherein the filter sections FA1 and FA2 can be cleaned separately from each other. A first rotary valve DV1, a second rotary valve DV2, and a third rotary valve DV3 are located in known locations: the first rotary valve DV1 in the suction duct SK, the second rotary valve DV2 in the second suction section SA2, and the third rotary valve DV3 in the first outlet section AA1. A fourth rotary valve DV4 is preferably located in the first suction section SA1 between the filter unit F and the first turbine T1. This allows the fourth rotary valve DV4 to close or release the first suction section SA1. If the vacuum cleaner 10 has a filter cleaning function, ambient air can flow into the vacuum cleaner 10 through either the first inlet or outlet opening O1 or the second inlet or outlet opening O2. Opening either the first inlet or outlet opening O1 or the second inlet or outlet opening O2 generates a cleaning flow AS that flows through the vacuum cleaner 10 in a direction opposite to the flow of the suction flow S.

[0060] The inflow air flow eLS entering the vacuum cleaner 10 through the first inlet or outlet opening O1 can preferably flow through the first turbine T1, further through the first suction part SA1, and apply ambient air to the open fourth rotary valve DV4 and the first filter part FA1. The ambient air entering the vacuum cleaner 10 through the first inlet or outlet opening O1 can form a first clean flow AS1, which allows backwashing of the first filter part FA1 of the filter unit F of the vacuum cleaner 10. This first clean flow AS1 and its curve are particularly shown in FIG. Figure 9 . During the cleaning and rinsing of the first filter section FA1 (preferably assigned to the first turbine T1), the suction operation of the vacuum cleaner 10 can continue using the second turbine T2. This ensures continuous suction operation of the vacuum cleaner 10, even during filter cleaning. In this embodiment of the present invention, the second rotary valve DV2, the third rotary valve DV3, and the fourth rotary valve DV4 are open, while the first rotary valve DV1 is closed. The inflowing airflow eLS is drawn into the vacuum cleaner 10 through the first inlet or outlet opening O1, while the suction flow S exits the vacuum cleaner 10 as the outflowing airflow aLS through the second inlet or outlet opening O2. The suction of ambient air through the first inlet or outlet opening O1 can be achieved simply by the pressure difference between the interior of the vacuum cleaner 10 and its surroundings. However, in the context of the present invention, it is also preferable to support suction by reversing the direction of rotation of the first turbine 1.

[0061] The inflow air flow eLS entering the vacuum cleaner 10 through the second inlet or outlet opening O2 can preferably flow through the second turbine T2, further through the second suction section SA2, and apply ambient air to the opened second rotary valve DV2 and the second filter section FA2. The ambient air entering the vacuum cleaner 10 through the second inlet or outlet opening O2 can form a second clean flow AS2, which allows backwashing of the second filter section FA2 of the filter unit F of the vacuum cleaner 10. This second clean flow AS2 and its curve are particularly shown in FIG. Figure 10 During the cleaning and rinsing of the second filter portion FA2 (preferably assigned to the second turbine T2), the suction operation of the vacuum cleaner 10 can be continued by the first turbine T1. Figure 10 In the illustrated design embodiment of the invention, the second rotary valve DV2 , the third rotary valve DV3 and the fourth rotary valve DV4 are also open, while the first rotary valve DV1 is closed.

[0062] The inflow air flow eLS is drawn into the vacuum cleaner 10 through the second inlet or outlet opening O2, while the suction flow S leaves the vacuum cleaner 10 as the outflow air flow aLS through the first inlet or outlet opening O1. The introduction of ambient air through the second inlet or outlet opening O2 can be achieved simply by the pressure difference between the interior of the vacuum cleaner 10 and its surroundings. However, within the context of the present invention, it may also be preferred to support this introduction by reversing the direction of rotation of the second turbine 2.

[0063] To control the opening and closing of the various valves and openings, and thus the cleaning of the filter F of the vacuum cleaner 10, the vacuum cleaner 10 may include a control device (not shown, without reference numerals). The control device may be designated for opening and closing the various valves and openings of the vacuum cleaner 10. The filter F of the vacuum cleaner 10 may be formed in two parts and, for example, include a first filter part FA1 and a second filter part FA2. In the context of the present invention, it may be preferred that the control device controls the valves and openings of the vacuum cleaner 10 in such a way that the filter parts FA1 and FA2 are cleaned substantially alternatingly. The term "substantially alternating" includes both the following situations: the cleaning of the filter parts FA1 and FA2 is performed strictly sequentially, and the cleaning of the filter parts FA1 and FA2 is performed with some temporal overlap. In the latter case, for example, the cleaning of the first filter part FA1 may still be in progress while the cleaning of the second filter part FA2 has already begun. However, in the context of the present invention, it may also be preferred to clean the filter parts FA1 and FA2 of the filter unit F as needed, for example, depending on the pressure loss in the area of ​​the filter unit F. In case of on-demand cleaning of the filter parts FA1 , FA2 of the vacuum cleaner 10 , a pressure transducer or sensor may be provided to detect the pressure in the suction duct or suction part of the vacuum cleaner 10 .

[0064] For example, the mesh G is provided in the connection area VB above the filter unit F (see Figures 8 to 12 ) can be closed when filter cleaning is triggered. This can be initiated, for example, by a control device. By closing the net G, the filter sections FA1 and FA2 can be fluidically separated from each other, preventing air exchange between the filter sections FA1 and FA2. After filter cleaning is complete, the net G can be reopened to restore the fluid connection between the filter sections FA1 and FA2. Various (preferably axial) motion elements can be used as actuators for the net G. For example, an electromagnetic lift element, a pneumatic pressure box, or an electric rotary drive can be used to drive or move the net G, but this is not limited to these.

[0065] Figures 11 to 13 An alternative design embodiment of a vacuum cleaner 10 and its valve assembly V is shown, wherein the vacuum cleaner 10 comprises a two-piece filter unit F which in turn has a first filter part FA1 and a second filter part FA2 . Figure 11 In general there is shown a potential configuration of a valve assembly V which allows alternate cleaning of the filter parts FA1, FA2. Figure 11In the embodiment of the invention shown, a rotary valve DV or a flap valve KV is arranged in the first outlet portion AA1 and in the suction duct SK between the turbines T1, T2 of the vacuum cleaner 10. These rotary valves DV or flap valves KV are preferably designed to close or release the first outlet portion AA1 or the suction duct SK. Figure 11 The illustrated embodiment has a first backwash opening RS1 and a second backwash opening RS2, wherein the first backwash opening RS1 is arranged in or leads to the first suction section SA1, and the second backwash opening RS2 is arranged in or leads to the second suction section SA2. Short sections of piping can be located between the backwash openings RS1 and RS2 and the suction sections SA1 and SA2. The backwash openings RS1 and RS2 can each be closed or released by a three-way valve WV, wherein the first three-way valve WV1 is preferably assigned to the first backwash opening RS1, and the second three-way valve WV2 is assigned to the second backwash opening RS2. Preferably, the first backwash opening RS1 and the first three-way valve WV1 are assigned to the first filter section FA1, and the second backwash opening RS2 and the second three-way valve WV2 are assigned to the second filter section FA2.

[0066] exist Figure 11 In the embodiment of the vacuum cleaner 10 shown, a rotary valve DV1 is present in the suction line SK between the turbines T1, T2. Figure 11 The vacuum cleaner 11 is shown in an operating state and is switched off when cleaning the first filter part FA1 (see Figure 12 ), which prevents flow between the turbines T1, T2, while the rotary valve DV1 in the suction duct SK of the vacuum cleaner 10 is opened when cleaning the second filter part FA2 (see Figure 13 ), so that the flow can successively pass through the turbines T1, T2 of the vacuum cleaner 10. For example, in the first outlet portion AA1 there may be a rotary valve DV3 which is Figure 11 The vacuum cleaner 11 is shown in the operating state and is opened when cleaning the first filter part FA1 (see Figure 12 ), while the rotary valve DV3 in the first outlet portion AA1 is preferably closed when cleaning the second filter portion FA2 (see Figure 13 ).

[0067] Figure 11 The filter unit F of the vacuum cleaner 10 shown has a connection area VB between the filter parts FA1, FA2. This connection area VB can be open or closed. Figure 11In the embodiment of the present invention, the connection region VB between the filter parts FA1, FA2 is, for example, opened, so that the filter parts FA1, FA2 form a so-called uniform filter unit F. When cleaning one of the two filter parts FA1, FA2, the connection region VB is preferably closed, so that the filter parts FA1, FA2 form a separate or independently functioning filter unit. The connection region VB can serve as a gate and include, for example, a mesh G.

[0068] Figure 12 The first three-way valve WV1 is shown as being openable to open the first backwash opening RS1. This advantageously generates a first backwash flow RSS1, which is suddenly introduced into the vacuum cleaner 10 due to the pressure difference between the interior of the vacuum cleaner 10 and its surroundings. Furthermore, the filter unit F or the first filter section FA1 is decoupled from the first turbine T1, so that no suction flow S flows through this half of the vacuum cleaner 10. The first backwash flow RSS1 can flow from the first backwash opening RS1 through the first filter section FA1, thereby cleaning it. While the first filter section FA1 is being cleaned, the second partial suction flow TS2 can continue to flow through the second filter section FA2 and the second turbine T2. This is advantageously made possible by a corresponding position of the second three-way valve WV2, which releases the second suction portion SA2 when the first filter portion FA1 is cleaned, so that a second partial suction flow TS2 from the dust collecting container 12 can flow through the second filter portion FA2 in the direction of the second turbine T2, and thus the suction operation of the vacuum cleaner 10 can be maintained in this way.

[0069] Similar to Figure 12 way, in Figure 13 , the cleaning of the second filter portion FA2 is shown, while at the same time the suction operation of the vacuum cleaner 10 is maintained by the first partial suction flow TS1 passing through the first filter portion FA1 and the first turbine T1 . Figure 13The second three-way valve WV2 is shown as being openable, thereby opening the second backwash opening RS2. This advantageously generates a second backwash flow RSS2, which is introduced suddenly into the vacuum cleaner 10 due to the pressure difference between the interior of the vacuum cleaner 10 and its surroundings. Furthermore, the filter unit F or the first filter section FA2 is decoupled from the first turbine T2, so that no suction flow S can flow through this half of the vacuum cleaner 10. The second backwash flow RSS2 can flow from the second backwash opening RS2 through the second filter section FA2, thereby cleaning it. While the second filter section FA2 is being cleaned, the first partial suction flow TS1 can continue to flow through the first filter section FA1 and the first turbine T1. This is advantageously made possible by a corresponding position of the first three-way valve WV1, which releases the first suction portion SA1 when cleaning the second filter portion FA2, so that a first partial suction flow TS1 from the dust collecting container 12 can flow through the first filter portion FA1 in the direction of the first turbine T1, in such a way that the suction operation of the vacuum cleaner 10 is maintained via the left half of the vacuum cleaner 10.

[0070] List of Reference Numerals 10. Vacuum cleaner 12 dust collection containers 14 Suction hose inlet T1 first turbine T2 second turbine V valve assembly KV Flap Valve KV1 first flap valve KV2 second flap valve DV Rotary Valve DV1 first rotary valve DV2 second rotary valve DV3 third rotary valve DV4 fourth rotary valve S Suction Flow TS1 Part 1 Suction Flow TS2 Part 2 Suction Flow AS Clean Stream AS1 first clean stream AS2 Second Clean Stream SK suction pipe SA1 first suction part SA2 second suction part AA1 first exit section AA2 second exit section O1 First inlet or outlet opening O2 second inlet or outlet opening F filter unit FA1 first filter section FA2 second filter section T(1 + 2)_S: Combined operation of the first and second turbines in series operation T(1 + 2)_P: Joint operation of the first and second turbines in parallel operation - p vacuum V Flow Rate SP switching point SM serial operation PM parallel operation eLS airflow into the vacuum cleaner aLS airflow leaving the vacuum cleaner -p(SP) vacuum value of SP switching point UB1 first vacuum range UB2 second vacuum range WV1 first three-way valve WV2 second three-way valve RS1 first backwash opening RS2 second backwash opening RSS1 first backwash flow RSS2 second backwash flow VB is the connection area between these filter parts G network

Claims

1. A vacuum cleaner (10) comprising a first turbine (T1) and a second turbine (T2), wherein: These turbines (T1, T2) are designed to generate a suction flow (S) for the introduction of dust, It is characterized by: The vacuum cleaner (10) has a valve assembly (V), wherein the valve assembly (12) is designed to allow the suction flow (S) to flow through the turbines (T1, T2) sequentially or in parallel.

2. The vacuum cleaner (10) according to claim 1, It is characterized by: The valve assembly (V) comprises at least one flap valve (KV) and / or at least one rotary valve (DV).

3. The vacuum cleaner (10) according to claim 1, It is characterized by: The valve assembly (V) comprises at least a first flap valve (KV1) and a second flap valve (KV2), wherein the first flap valve (KV1) is arranged behind the first turbine (T1) in the direction of the suction flow, and wherein the second flap valve (KV2) is arranged in front of the second turbine (T2) in the direction of the suction flow.

4. The vacuum cleaner (10) according to claim 3, It is characterized by: The first flap valve (KV1) allows the suction flow (S) to flow in the direction of the first inlet or outlet opening (O1) or in the direction of the second turbine (T2), and the second flap valve (KV2) enables or prevents the suction flow (S) from flowing through the second turbine (T2).

5. The vacuum cleaner (10) according to claim 1 or 2, It is characterized by: The valve assembly (V) comprises at least a first rotary valve (DV1) and a second rotary valve (DV2), wherein the first rotary valve (DV1) is arranged between the first turbine (T1) and the second turbine (T2), and wherein the second rotary valve (DV2) is present between the second turbine (T2) and the filter unit (F).

6. The vacuum cleaner (10) according to claim 5, It is characterized by: The first rotary valve (DV1) is designed to close or release a suction line (SK) between the first turbine (T1) and the second turbine (T2), wherein the second rotary valve (DV2) is designed to close or release a second suction section (SA2) between the second turbine (T2) and a filter unit (F).

7. The vacuum cleaner (10) according to claim 5 or 6, It is characterized by: The valve assembly (V) comprises a third rotary valve (DV3), wherein the third rotary valve (DV3) is arranged between the first turbine (T1) and the first inlet or outlet opening (O1).

8. The vacuum cleaner (10) according to any one of claims 5 to 7, It is characterized by: The third rotary valve (DV3) is designated for closing or releasing a first outlet portion (AA1) between the first turbine (T1) and the first inlet or outlet opening (O1).

9. The vacuum cleaner (10) according to one of the preceding claims, It is characterized by: The valve assembly (V) is designated to allow a cleaning flow (AS) to flow through the first turbine (T1) and / or the second turbine (T2) in a direction opposite to the suction flow (S).

10. The vacuum cleaner (10) according to one of the preceding claims, It is characterized by: The vacuum cleaner (10) comprises a filter unit (F) for filtering the suction flow (S), wherein the filter unit (F) has a first filter part (FA1) and a second filter part (FA2), wherein the first filter part (FA1) is assigned a first cleaning area (AB1) and the second filter part (FA2) is assigned a second cleaning area (AB2).

11. The vacuum cleaner (10) according to claim 10, It is characterized by: The clean flow (AS) flows through the first turbine (T1) during cleaning of the first filter portion (FA1), and wherein the clean flow (AS) flows through the second turbine (T2) during cleaning of the second filter portion (FA2).

12. The vacuum cleaner (10) according to claim 10 or 11, It is characterized by: The valve assembly (V) comprises a first three-way valve (WV1) and a second three-way valve (WV2), wherein the first three-way valve (WV1) is designated for closing or releasing a first backwash opening (RS1), wherein a first backwash flow (RSS1) flows through the first filter portion (FA1), and wherein the second three-way valve (WV2) is designated for closing or releasing a second backwash opening (RS2), wherein a second backwash flow (RSS2) flows through the second filter portion (FA1).

13. The vacuum cleaner (10) according to any one of claims 5 to 12, It is characterized by: The valve assembly (V) includes a fourth rotary valve (DV4), wherein the fourth rotary valve (DV4) is arranged between the first turbine (T1) and the filter unit (F) and is designated to close or release the first suction portion (SA1) between the first turbine (T1) and the filter unit (F).

14. A method for operating a vacuum cleaner (10) as claimed in one of the preceding claims, wherein: The method is characterized by the following method steps: a) providing a vacuum cleaner (10) having a first turbine (T1) and a second turbine (T2), b) controlling the valve assembly (V) of the vacuum cleaner (10) so that the suction flow (S) flows through the turbines (T1, T2) sequentially or in parallel.

15. The method according to claim 14, It is characterized by: The method comprises detecting and / or evaluating operating data of the vacuum cleaner (10), wherein a valve assembly (V) of the vacuum cleaner (10) is controlled in dependence on previously detected operating data.

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