Dust hoods for power tools

Abstract

The invention relates to a dust hood for a power tool, wherein the dust hood (1) comprises an extraction area (3) and an inner area (6), wherein a suction hose (4) from a dust suction device flows into the dust hood in the extraction area. The dust hood has a curved portion (5) in the extraction area, wherein the curved portion enables the impact surge generated during the filter cleaning operation of the dust suction device to be attenuated by reflection, wherein the attenuation generates a reverse impact, wherein the reverse impact avoids the situation where the vacuum in the inner area (6) of the dust hood is destroyed during the filter cleaning, wherein the vacuum is generated by the dust suction device and conveyed by the suction hose.

Description

Technical Field

[0001] The invention relates to a dust hood for a power tool, wherein the dust hood comprises an extraction area, in which a suction hose from a dust suction device leads into the dust hood. The dust hood has a curved portion in the extraction area, wherein the curved portion enables the impact surge generated during the filter cleaning operation of the dust suction device to be dispersed or deflected by reflection. Background Art

[0002] When working with a power tool (e.g. a drill, a cutter or an angle grinder or a slot milling cutter), dust is often generated, which may be harmful to human health, especially if the dust is inhaled. The prior art discloses a dust hood, by which the working device of such a power tool (e.g. a drill bit, a chisel or a cutting disc) can be covered. Such a dust hood is preferably used to collect the dust generated when working with the power tool. The dust hood can preferably be connected to a dust suction device or a dust collector, so that the dust collected in the dust hood can be extracted by the dust suction device or the dust collector. This is usually done by generating a vacuum, which is transmitted to the dust hood via a suction hose. For the connection of the dust suction device or the dust collector, the dust hood preferably has a suction hose connection in the area where the suction hose passes into the dust hood. For the purposes of the present invention, this area of ​​the dust hood is preferably referred to as an extraction area.

[0003] In the case of conventional dust hoods known from the prior art, dust leakage may occur. Such dust leakage is known, for example, when a conventional dust hood is connected to a slot milling cutter. For the purposes of the present invention, the slot milling cutter is preferably designed, for example, to form a slot on the wall so that the line can be laid in the "knocked out" slot. The problem with leakage points in areas where dust can pass through a conventional dust hood into the outside, that is to say into the surrounding environment, is that the corresponding certification standards stipulate lower limit values ​​for dust emissions, and dust emissions (if any) are difficult to observe when using a non-sealed dust hood. In particular, leakage may disadvantageously lead to the inability to keep enough dust away from the operator of the power tool, as a result of which the dust is inhaled by the operator and may enter his or her respiratory tract. Dust typically includes dust particles that may be small enough to enter the lungs, for example. Other dust particles may be harmful to health or carcinogenic.

[0004] In particular, dust escape is observed in conventional dust hoods during filter cleaning. During filter cleaning, the filter of the dust collector or dust extraction device cleans such dust that accumulates in the filter during operation. Such dust may, for example, form a filter cake in the filter area, which is removed by the filter cleaning process. For example, during filter cleaning, there may be a short interruption in the vacuum generation in the dust extractor, so that the pressure conditions in the dust extractor change for a short time, thereby generating a pressure surge acting on the filter. The filter cake can be loosened or released from the filter by the pressure surge. In other cases, a reverse airflow can actively blow through the filter, as a result of which the filter cake is released from the filter. These measures can be performed once or can be repeated in a cleaning cycle. For example, a cleaning cycle of a dust extraction device can include three cleaning surges. The implementation of the cleaning cycle can, for example, be automatically started at regular intervals or controlled as required.

[0005] Because during the cleaning operation, a (pressure) surge is frequently applied to the filter, this operation is preferably also referred to as a knock-out operation for the purposes of the present invention. This knock-out operation often causes backblowing in the suction hose or inside the dust hood, which in the case of conventional dust hoods known from the prior art can undesirably lead to the discharge of dust clouds. Summary of the invention

[0006] The object on which the invention is based is to overcome the above-mentioned disadvantages of the prior art and to provide a dust hood for a power tool which, on the one hand, is designed to be particularly tight and, on the other hand, makes it possible to effectively prevent dust from entering the respiratory tract of the power tool operator. In addition, it is intended to use the dust hood provided to prevent dust clouds from being discharged when the filter is cleaned.

[0007] According to the present invention, a dust hood for a power tool is provided, wherein the dust hood comprises an extraction area and an inner area, wherein a suction hose from a dust suction device enters the dust hood in the extraction area. The dust hood is characterized in that the dust hood has a curved portion in the extraction area, wherein the curved portion is designed to attenuate the impact surge from the dust suction device and delivered to the inner area of ​​the dust hood through the suction hose, the attenuation generating a reverse impact, wherein the reverse impact avoids the situation where the vacuum in the inner area of ​​the dust hood is destroyed during filter cleaning, the vacuum being generated by the dust suction device and delivered by the suction hose. In particular, the preferably inwardly formed curved portion of the dust hood wall ensures that at least one cleaning surge is deflected and prevents the cleaning surge from penetrating from the extraction space into the interior of the dust hood.

[0008] In the context of the present invention, a defined curved portion on the inner wall of the dust hood is proposed, which is particularly arranged in the extraction area of ​​the dust hood. The curved portion advantageously ensures that possible impact impacts or pressure waves that may be generated during the filter cleaning of the dust suction device are dispersed and / or deflected inside the dust hood by its characteristic configuration, and the proposed dust hood is preferably connected to the dust suction device. Preferably, the dust hood that can be preferably connected to the power tool is connected to the dust suction device, as a result of which the dust generated when working with the power tool can be extracted by the dust suction device. Here, the pressure waves and / or impact surges generated during the filter cleaning operation of the dust suction device can be transmitted to the dust hood via a suction hose. The extraction of dust and dust particles is preferably carried out by generating a vacuum by the dust suction device, which is transmitted to the dust hood by a suction hose, and the suction hose connects the dust hood to the dust suction device. Therefore, the vacuum is preferably also present in the dust hood.

[0009] The deflection of the impact surge that can be achieved by the curved portion of the dust hood preferably produces a reverse impact, which advantageously makes it possible to prevent the vacuum in the inner area of ​​the dust hood from being destroyed during filter cleaning, which is generated by the dust suction device. This also allows the dust generated during filter cleaning to be collected in the dust hood when working with a power tool, and then extracted, especially when the filter cleaning is finished or the full suction power of the dust suction device is available again. In the case of a conventional dust hood without a curved portion on the inner wall of the extraction area, it has been easy to occur so far that the impact surge generated during filter cleaning penetrates into the working device of the power tool and undesirably causes the outflow of dust clumps. In other words, in the case of a conventional dust hood, it may occur that due to the impact surge and pressure waves generated during filter cleaning, dust clumps are discharged from the dust hood, as a result of which the released dust may enter the respiratory tract of the operator. Dust clumps are especially generated by the fact that the vacuum in the dust hood is destroyed, which is advantageously prevented in the case of the dust hood proposed according to the present invention by providing a defined curved portion. The curved portion advantageously ensures that the impact surge is reflected on the wall in which the curved portion is present. In particular, the impact surge that hits the curved wall can be conceptually decomposed into a plurality of separate surges extending substantially in parallel. Preferably, these conceptually separate impact surges are reflected on the curved wall of the dust hood in such a way that these impact surges return to the extraction area and at least partially disappear or attenuate each other. As a result, the impact surge is advantageously effectively prevented from propagating into the inner area of ​​the dust hood and destroying the vacuum therein.

[0010] Surprisingly, the provision of a curved section not only ensures the attenuation or disappearance of reflected impact surges. It has been shown that the reflected impacts are advantageously also able to attenuate and / or disappear newly arriving filter cleaning surges. This can be particularly advantageous when the filter cleaning process of the dust extraction device to which the power tool is connected comprises a plurality of impacts or compressed air surges which arrive in succession at the dust hood. Advantageously, the proposed curved section of the dust hood allows both already reflected and newly arriving impacts and / or compressed air surges, which the filters of the dust extraction device use for cleaning or are blown through by them to release the filter cake, to be attenuated or disappeared. Figure 2 This attenuation is particularly illustrated by arrows in the lower region of the dust hood. In particular, the newly arriving impact surge generates a vortex by the reflected impact surge when passing through the extraction space of the dust hood in such a way that further penetration of the impact surge into the interior of the dust hood, which is separated from the extraction space by the baffle, is effectively avoided. This advantageously ensures that the vacuum for extracting dust inside the dust hood is not adversely affected.

[0011] For the purpose of the present invention, it is preferred that the curved portion inside the dust hood is defined by the ratio of height to diameter. For the purpose of the present invention, the term "diameter of the curved portion" preferably describes the distance between two points where the curved portion starts or ends on an otherwise substantially smooth wall. In other words, the diameter exists as a length between two points that can be understood as the starting point and end point of the curved portion. The diameter of the curved portion can be in the range of, for example, 15 mm to 35 mm. For the purpose of the present invention, the term "height of the curved portion" preferably describes the length of the curved portion protruding on the otherwise substantially smooth wall of the dust hood. In other words, the height can be understood as the distance between the highest point of the otherwise substantially smooth wall and the curved portion. The height of the curved portion can be in the range of, for example, 5 mm to 25 mm. The ratio of height to diameter can be in the range of, for example, 0.14 to 1.7, and a specific value less than 1 is preferred. In other words, it is preferred for the purpose of the present invention that the diameter of the curved portion is greater than its height, although the height of the curved portion may also be greater than the diameter in an alternative embodiment. When determining the ratio of height to diameter, the value of the height of the curved portion is preferably set relative to the value of the diameter of the curved portion. Preferably, these values ​​can be divided by one another, wherein the height value forms the numerator of the resulting quotient and the diameter value forms the denominator of the ratio described by the quotient. A possible configuration of the curved portion is shown in the accompanying drawings. It is particularly preferred for the purposes of the present invention that the curved portion is formed inwardly, that is to say inwardly into the extraction space of the dust hood. In this case, the curved portion can be considered in particular as an indentation. However, it may also be preferred that the curved portion is formed outwardly.

[0012] The dust generated when working with power tools can include dust particles of different sizes or diameters and geometries. For example, very small particles that are barely visible to the human eye can be part of the dust. However, it can also happen that when working with power tools, for example in the course of wall or masonry work, relatively large processed particles are generated which are initially too large to be transported via the suction hose connecting the dust hood to the dust extraction device into a collection container of the dust extraction device. Such relatively large processed particles can therefore initially not be extracted by the dust extraction device.

[0013] In order to be able to further process such processed coarse particles and in particular to be able to extract them with a dust extraction device, the dust hood can include a baffle, so that a coarse filtering effect can advantageously be produced by the baffle. This can prevent larger breakages, processed products that may occur during operation of the power tool and may enter the inner area of ​​the dust hood from clogging the suction area. On the contrary, the provision of the baffle advantageously ensures that the processed coarse particles rebound from the baffle plate and fall back into the working area of ​​the power tool or the interior of the dust hood, where they are further comminuted by working means, such as a cutting disc, until the comminuted particles fit through the opening in the hose area and can be conveyed to the dust extraction device via the suction hose.

[0014] It is known that the working device of a power tool may break under high mechanical loads. This undesirable breakage may pose a risk to the operator of the power tool, for example when he or she is hit by the fragments of the broken working device. The risk of injury is especially caused by sharp-edged, pointed or sharp fragments, which may cause cuts. For the purpose of the present invention, it is preferred that the separate wall area of ​​the dust hood is a double-walled design, wherein the preferred double-walled area of ​​the dust hood wall can advantageously absorb the kinetic energy of the fragments that are broken into fragments in the case of the possible breakage of the working device of the power tool, as a result, the operator of the power tool is particularly effectively protected from being injured or being affected by the fragments. The working device of the power tool can be formed in particular by a cutting disc or a cutting disc, for example when the working device is a cutting machine or an angle grinder. For the purpose of the present invention, it is preferred that those areas of the dust hood wall that may contact with the generated fragments in the case of the cutting disc or the cutting disc breakage have a double-walled design, that is to say a reinforced design, to protect the operator of the power tool from being injured.

[0015] For the purpose of the present invention, it may also be preferred that the wall of the dust hood is a continuous double-wall design. For example, for safety reasons, the continuous double-wall closure of the dust hood may be advantageous. It may also be preferred that the wall is a design of at least double walls, wherein the wall can have more than two layers or be formed by more than two layers or more than two separate walls in whole or in part. In the case of a double-wall or multi-wall configuration of a wall or wall area, the area between the separate walls can be a hollow design or filled with a filler. The example of a filler material that can be used is a lightweight material, to keep the weight of the dust hood low. For example, a plastic foam material can be used as a filler between the separate walls of the dust hood. The separate wall of the dust hood preferably has a thickness in the range of 0.1 mm to 3 mm, and the wall thickness is particularly preferred in the range of 2 mm to 3 mm. In a word, the dust hood wall preferably has a wall thickness of at least 5 mm.

[0016] The dust hood preferably comprises an electrically conductive base material. In other words, it is preferred that the dust hood or its wall is formed by an electrically conductive material. It is preferred that the inner side of the proposed dust hood has an electrically conductive base material in particular. The provision of an electrically conductive base material advantageously ensures that electrostatic charges that may be generated inside the dust hood due to the generally dry dust are transferred to the suction hose via the dust hood. In this way, as a particular advantage of the present invention, it is ensured that electrostatic charges are dissipated via the dust suction device. It is particularly preferred for these purposes that the dust discharge is preferably configured as a completely coherent electrostatic conduction. In particular, the dust discharge includes an area from the source of the dust to its storage in the dust container. It is preferred in an exemplary embodiment of the present invention that the dust hood comprises a wall made of an electrically conductive material, wherein the material transfers the electrostatic charges that may be generated due to the dry dust to the suction hose via the dust hood, and thus dissipation via the dust suction device can be advantageously ensured. It is preferred that the entire dust discharge from the source to the storage of the dust in the dust container is configured as a coherent electrostatic conduction.

[0017] For example, electrically conductive or electrically conducting plastics can be used as base materials for dust hoods or walls and components of dust hoods. It may also be preferred for the purposes of the present invention that conductive additives are mixed with primary particles for producing dust hoods or components thereof, whereby an electrostatically conductive material is advantageously obtained. For example, metal fragments can be mixed as additives with plastics for producing dust hoods or components thereof.

[0018] Electrostatic charges in the dust hood material are generated, for example, by friction between dust fragments or dust particles and the plastic material of the dust hood, preferably during operation of a power tool or during dust formation. This charging occurs in particular when the dust is very dry, that is to say, for example, in summer or during long dry periods. In the case of very high electrostatic charging, undesired spontaneous discharges by the user may occur if the charges are not dissipated in a targeted and conscious manner via corresponding grounding. For this reason, the transitions between the individual components of the dust hood are also preferably designed to be conductive to allow the charge to dissipate.

[0019] Preferably, providing the dust hood or its components with electrostatically conductive materials allows charge equalization inside the power tool. This is particularly advantageous when charges with different signs accumulate at different areas of the tool and thus form an electric field. The preferred conductive material of the dust hood can provide the possibility of charge equalization, wherein excess electrons can flow out of one area of ​​the tool and can compensate for the lack of electrons in another area of ​​the tool. Avoiding uncontrolled discharge or charge equalization operation also makes it possible, in particular, to significantly reduce flying sparks and reduce the risk of fire during operation of the power tool.

[0020] For the purpose of the present invention, it is preferred that the inner area of ​​the dust hood is designed to be uniform in terms of flow dynamics, as a result of which aerodynamic turbulence in the interior is particularly effectively avoided. The inner area of ​​the dust hood particularly includes the area of ​​the preferred hollow interior of the dust hood, in which dust occurs due to the operation of the power tool. For the purpose of the present invention, this area may also be preferably referred to as the working area of ​​the power tool or working device. For example, the working tool may be a cutting machine or an angle grinder including a cutting disc or a cutting disc as a working device. For the purpose of the present invention, it is particularly preferred that the interior of the dust hood includes the working area of ​​the working device, in which case, in the preferred configuration of the present invention, the working device may be a cutting disc or a cutting disc. The interior of the dust hood is designed to be uniform in terms of flow dynamics or aerodynamics, and in particular, the particularly dust-free operation of the power tool can be ensured. For the purpose of the present invention, it is very particularly preferred that the inner wall of the dust hood is particularly designed to be uniform in terms of flow dynamics or aerodynamics, and these inner walls preferably define the interior of the dust hood. The interior of the dust hood is designed to be uniform in terms of flow dynamics or aerodynamics, and can be achieved, for example, by arranging a particularly smooth inner wall. For the purposes of the present invention it may also be preferred if the geometrical structure or the spatial configuration of the interior of the dust collecting hood leads to or contributes to the formation of an interior of the dust collecting hood which has a uniform design in terms of flow dynamics or aerodynamics.

[0021] In a preferred embodiment of the present invention, the dust hood comprises a baffle as abrasive wear protection or temperature protection. For the purpose of the present invention, preferably, the baffle is arranged on the front side of the dust deflector. For the purpose of the present invention, the dust deflector preferably constitutes a device for improving the feeding or deflection of dust particles into the extraction area of ​​the dust hood. If the baffle comprises a metal or a metal alloy or is formed by a metal grid, the baffle can also be used to protect the plastic part of the dust hood from sparks or scattered sparks. The baffle is preferably designed to have a high wear resistance to withstand the high mechanical and / or thermal loads caused by dust particles and / or sparks. The provision of the baffle as a protection for the plastic component of the dust hood advantageously significantly extends the service life of the proposed dust hood. The baffle also preferably absorbs thermal energy, i.e. heat, and thereby ensures cooling of the interior of the dust hood by virtue of its good thermal conductivity. The baffle can in particular be formed by a baffle sheet, which is preferably arranged on the inner side of the dust deflector. In one embodiment of the invention, it may be preferred that the baffle is formed by a grid which, for example, comprises metal or is formed from metal.

[0022] The dust hood is preferably formed by two mutually corresponding halves, which together form the basic body of the dust hood. The fastening of the baffle is preferably formed by clamping the two dust hood halves. It is completely surprising that the provision of the baffle in the region of the dust deflector inside the dust hood can provide a combination of additional abrasive wear protection and further fracture protection. A further advantage of the provided baffle is the fact that the baffle can be used to achieve a coarse filtration of dust, wherein the coarse filtration in particular allows the processed larger particles that cannot initially be extracted by the suction hose of the dust suction device to be returned to the dust hood interior so that these larger particles can be further comminuted by the cutting disc of the power tool. The comminution produces processed smaller particles, the size of which advantageously allows the comminuted processed particles to pass through the suction hose and be extracted by the dust suction device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] 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 readily consider these features individually and combine them to produce useful further combinations.

[0024] In the drawings, the same components and components of the same type are indicated by the same reference numerals. In the drawings:

[0025] Figure 1 A cross-sectional view showing a preferred configuration of a dust collection hood;

[0026] Figure 2 A cross-sectional illustration of a preferred embodiment of the extraction area of ​​the dust hood is shown;

[0027] Figure 3 A view showing a preferred configuration of the baffle; and

[0028] Figure 4 A view showing a preferred embodiment of a dust hood assembly is shown. DETAILED DESCRIPTION

[0029] Figure 1 A cross-sectional view of a preferred configuration of the proposed dust collecting hood 1 is shown. In particular, Figure 1 A curved section 5 which is preferably present on the wall of the dust hood 1 is shown. It is particularly preferred for the purposes of the present invention that the curved section 5 is arranged on the wall opposite the outlet of the suction hose 4. The area in which the suction hose 4 opens into the dust hood 1 is preferably also referred to as the extraction area 3 of the dust hood 1. The suction hose 4 preferably connects the dust hood 1 to a dust extraction device (not shown), wherein preferably both a vacuum and a surge flow, which is generated by the dust extraction device to suck in dust, are conveyed to the dust hood 1 by means of the suction hose 4 from the dust extraction device, the vacuum being generated by the dust extraction device to suck in dust, the surge flow being generated during filter cleaning. The surge flow generated by the dust extraction device during filter cleaning and guided into the dust hood 1 by the suction hose 4 can, for example, form a surge pressure jet which, in the case of the proposed dust hood 1, first strikes the curved section 5 of the dust hood wall. Due to the specific configuration of the curved section 5, the surge pressure jet is preferably split and diverted or deflected in different directions. In particular, the reflected impact surges are superimposed in the curved region 5 of the dust collecting hood 1 , with the result that the reflected impact surges advantageously weaken or eliminate each other.

[0030] The particular advantage of the invention achieved by this attenuation or disappearance of the reflected impact surge is that the impact surge does not penetrate further into the inner region 6 of the dust hood 1. This advantageously leads to the fact that a vacuum can also be maintained in the inner region 6 of the dust hood 1 during filter cleaning of the dust suction device. This overcomes the disadvantages of conventional dust hoods, which often eject dust particle clusters from various openings during filter cleaning of the dust suction device. Maintaining a vacuum in the inner region 6 of the proposed dust hood 1 advantageously avoids such a release of dust clusters, as a result of which the respiratory load of the operator of the power tool 2 (not shown) can be significantly reduced by the invention.

[0031] While the vacuum is maintained during filter cleaning, dust generated during this period by the operation of the power tool 2 can advantageously be collected in the inner area 6 of the dust hood 1. After the filter cleaning is completed, the dust extraction device can generate a vacuum again, which can be conveyed to the dust hood 1 by the suction hose 4. In this way, dust particles collected in the dust hood 1 during filter cleaning can be extracted by the suction hose 4 after the filter cleaning is completed and stored in the collection container of the dust extraction device.

[0032] also, Figure 1 Various regions of the dust hood wall 7 of the dust hood 1 of at least partially double-walled design are shown. Thus, the region of the dust hood wall 7 of the dust hood 1 has a more stable design and provides better protection for the operator of the power tool 2, for example, when the working device of the power tool 2 is damaged or broken. The fragments that appear in the event of such damage are absorbed by the preferably double-walled region of the dust hood wall 7, whereby the escape of fragments from the dust hood 1 can be advantageously avoided. In addition, in particular the outer wall of the dust hood wall 7, which is at least partially double-walled, can have elastic properties, which enable the double-walled wall region to withstand deformation forces, for example, in the event of a fall of the dust hood 1 or the power tool 2. As a result, the double-walled wall region advantageously also ensures an improved fall protection for the proposed dust hood 1 or the power tool 2.

[0033] For the purposes of the present invention, it is preferred that the device chain of the inner dust area is configured to be electrostatically conductive. As a result, electrostatic charges occurring on the suction hose 4 are advantageously dissipated to the dust suction device, where they can be safely dissipated to the ground via the grounding conductor. In this way, it is advantageously possible to dissipate charges both in mains-powered and battery-powered power tools 2.

[0034] exist Figure 1 In the preferred embodiment of the present invention shown in FIG. 8 , a baffle 8 is also depicted. Figure 1 The baffle 8 in the exemplary embodiment shown in the embodiment is designed as a metal grid. The metal grid makes it possible to prevent relatively large dust or stone particles from entering the extraction area 3 of the dust hood 1, which particles are also preferably referred to as processed particles for the purposes of the present invention. In other words, the baffle 8 marks a boundary between the inner area 6 of the dust hood 1 present in the lower area of ​​the dust hood 1 and the extraction area 3 of the dust hood 1 present in the upper area of ​​the dust hood 1. The baffle 8 preferably ensures that relatively large dust particles or stone particles are thrown back into the inner area 6 of the dust hood 1, where they can be crushed again or further crushed when they enter the working area of ​​the working device of the power tool 2. If the diameter of the dust particles or stone particles after reprocessing by the working device of the power tool 2 is suitable for passing through the opening of the baffle 8, the processed particles will enter the extraction area 3 of the dust hood 1 and be extracted in this extraction area by the dust suction device. For this purpose, these particles are first sucked into the suction hose 4 and then into the collection container of the dust suction device.

[0035] Figure 2A cross-sectional illustration of a preferred embodiment of the extraction area 3 of the dust hood 1 is shown. This is preferably the upper area of ​​the dust hood 1, into which the suction hose 4 of the dust extraction device opens. The curved section 5 is preferably arranged opposite to this opening of the suction hose 4 into the dust hood 1, which advantageously causes a splitting and / or deflection of the impact surge of the dust extraction device. For the purposes of the present invention, it is preferred that the curved section 5 produces a refraction of the impact pressure surge, so that the impact pressure surge is attenuated in such a way that it can no longer enter the inner area 6 of the dust hood 1. In Figure 2 In the exemplary embodiment of the invention shown in , the curved portion 5 constitutes an indentation, that is to say a concave indentation in that area of ​​the wall of the dust hood 1 opposite the opening of the suction hose 4. In particular, the indentation for the purposes of the present invention preferably constitutes an inward arch, that is to say there is a curved portion in a certain area entering the interior of the dust hood 1. The impact surge output by the dust suction device during filter cleaning will preferably move further straight when leaving the suction hose 4 and thereby hit the dust hood wall at a specific angle defined by the contour of the curved wall area. For the purposes of the present invention, the term "curved wall area" preferably represents a wall area of ​​the dust hood 1 including the curved portion 5 of the dust hood wall.

[0036] The impact surge is reflected by the wall of the dust hood 1 according to the impact angle and enters the extraction area 3 of the dust hood 1. That wall area of ​​the dust hood 1 opposite to the opening of the suction hose 4, which preferably also includes the bend 5, is particularly configured so that the reflected impact surge disappears or at least greatly weakens by means of the superposition effect. Therefore, the impact cannot penetrate further into the inner area 6 of the dust hood 1. This surprisingly leads to the fact that the destruction of the vacuum in the inner area 6 of the dust hood 1 can be effectively avoided, as a result of which, during filter cleaning, in particular no dust clouds are ejected or blown out from the interior of the proposed dust hood 1 to the surroundings outside the power tool 2. The bend 5 in the dust hood wall leads in particular to the fact that the reflected impact surge actually fanned out and dispersed in different directions, wherein, considering the small available space in the extraction area 3 of the dust hood 1, the reflected impact surges are advantageously superimposed in such a way that these impact surges are substantially attenuated or completely disappear. Thus, the substantially parallel impact surges that first hit the dust hood wall are reflected into the entire extraction area 3 of the dust hood 1, where they attenuate each other. Figure 2 The lower part of shows this reflection or refraction of the impact surge. Here, the black arrows preferably represent the impact surge that is conceptually broken down into individual impact surges. These individual impact surges generated by the dust suction device during filter cleaning are refracted or reflected at the curved dust hood wall and deflected into the extraction area 3 of the dust hood 1. Figure 2The bottom part of the diagram preferably shows the conceptual individual impacts of reflection or refraction by means of white arrows.

[0037] Figure 3 A view showing a preferred embodiment of a dust hood assembly is shown. Figure 3 In particular, the preferred embodiment of the proposed dust collection hood 1 is shown. Figure 3 In particular, the upper region of the dust hood 1 is shown, which is formed by the extraction region 3. A suction hose 4, which connects the dust hood 1 to a dust extraction device, leads to the extraction region 3. An interior region 6 of the dust hood 1 is present in the lower region of the dust hood 1, which is closed by a baffle 8 (see Figure 4 ) is separated from the extraction area 3.

[0038] Figure 4 A view showing a preferred configuration of a baffle 8 of the proposed dust hood 1 is shown. Located above the baffle 8 is the extraction area 3 of the dust hood 1 with a curved section 5, which in the depicted exemplary embodiment of the invention is designed as a metal grid. The curved section 5 or the curved wall area of ​​the dust hood 1 is preferably arranged opposite the opening of a suction hose 4, via which the dust hood 1 can be connected to a dust extraction device. Located below the metal grid is the interior area 6 of the dust hood 1, in which working means of, for example, a power tool 2 can be present.

[0039] It is preferred for the purposes of the invention that the dust hood 1 comprises two shells or halves forming the basic body of the dust hood 1. The two shells hold the metal grid and sandwich it between them. As a result, larger processed sheet fragments or processed particles are retained and do not clog the suction hose 4. This makes safe work with the power tool 2 or the dust suction device possible without interruptions due to clogged hose lines. In addition, the provision of the baffle 8 reduces the occurrence of dust clusters, which can occur as a disadvantageous consequence when the extraction line is clogged.

[0040] Reference numerals list

[0041] 1 Dust hood

[0042] 2 Power Tools

[0043] 3 Extraction area

[0044] 4 Suction hose

[0045] 5. Bending part

[0046] 6Inner area of ​​the dust hood

[0047] 7Double wall dust hood

[0048] 8 Baffle

Claims

1. A dust hood (1) for a power tool (2), wherein: The dust hood comprises an extraction area (3) and an inner area (6), wherein a suction hose (4) from a dust suction device enters the dust hood (1) in the extraction area, and is characterized in that the dust hood (1) has a bent portion (5) in the extraction area (3), wherein the bent portion (5) is designed to attenuate an impact surge flow from the dust suction device and delivered to the inner area (6) of the dust hood (1) through the suction hose (4), wherein the attenuation produces a reverse impact, wherein the reverse impact avoids the situation in which the vacuum in the inner area (6) of the dust hood (1) is destroyed when the filter is cleaned, wherein the vacuum is generated by the dust suction device and delivered by the suction hose (4).

2. The dust collecting hood (1) according to claim 1, characterized in that: The curved portion (5) is defined by the ratio of height to diameter.

3. The dust collecting hood (1) according to claim 1 or 2, characterized in that: The individual wall areas of the dust hood (1) are of double-wall design.

4. The dust collecting hood (1) according to claim 1 or 2, characterized in that: The dust collecting hood (1) comprises a conductive base material.

5. The dust collecting hood (1) according to claim 1 or 2, characterized in that: The inner region (6) of the dust collecting hood (1) is designed to be homogeneous in terms of flow dynamics, as a result of which aerodynamic turbulence in the inner region (6) is avoided.

6. The dust collecting hood (1) according to claim 1 or 2, characterized in that: The dust collecting hood (1) comprises a baffle (8) as abrasive wear protection and temperature protection.

7. The dust collecting hood (1) according to claim 6, characterized in that: The baffle (8) separates the extraction area (3) from the inner area (6) of the dust collecting hood (1).

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