阅读说明：本技术 用于动力工具的集尘罩 (Dust cage for power tool ) 是由 F·胡贝尔 X·汉斯尔梅尔 于 2020-03-24 设计创作，主要内容包括：本发明涉及一种用于动力工具的集尘罩,其中,该集尘罩包括提取区域,来自粉尘抽吸装置的抽吸软管在该提取区域中通入该集尘罩。该集尘罩在该提取区域中具有弯曲部分,其中,该弯曲部分使得在粉尘抽吸装置的过滤器清洁操作中产生的冲击涌流可以通过反射而衰减。(The invention relates to a dust hood for a power tool, wherein the dust hood comprises an extraction region, in which a suction hose from a dust suction device opens into the dust hood. The dust hood has a curvature in the extraction region, wherein the curvature allows an impact surge generated during a filter cleaning operation of the dust suction device to be damped by reflection.)

1. Dust cage (1) for a power tool (2), wherein the dust cage comprises an extraction region (3) in which a suction hose (4) from a dust suction device opens into the dust cage (1),

it is characterized in that the preparation method is characterized in that,

the dust hood (1) has a curvature (5) in the extraction region (3), wherein the curvature (5) is designed to attenuate an impinging surge flow coming from the dust suction device and conveyed through the suction hose (4) to an inner region (6) of the dust hood (1).

2. Dust cage (1) according to claim 1,

it is characterized in that the preparation method is characterized in that,

the damping produces a reverse impact, wherein the reverse impact avoids a situation in which the vacuum in the interior region (6) of the dust hood (1), which is generated by the dust suction device and conveyed by the suction hose (4), is broken during filter cleaning.

3. Dust cage (1) according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the curved portion (5) is defined by a ratio of height to diameter.

4. Dust cage (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the separate wall region (7) of the dust cage (1) is of double-walled design.

5. Dust cage (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the dust cage (1) comprises an electrically conductive base material.

6. Dust cage (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the inner region (6) of the dust hood (1) is designed to be uniform in terms of flow dynamics, as a result of which aerodynamic turbulence in the interior (6) is particularly effectively avoided.

7. Dust cage (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the dust cage (1) comprises a baffle (8) for abrasive wear protection and temperature protection.

8. Dust cage (1) according to claim 7,

it is characterized in that the preparation method is characterized in that,

the baffle (8) separates the extraction region (3) from the inner region (6) of the dust cage (1).

Technical Field

The invention relates to a dust hood for a power tool, wherein the dust hood comprises an extraction region, in which a suction hose from a dust suction device opens into the dust hood. The dust cage has a curvature in the extraction region, wherein the curvature allows an impact surge generated during a filter cleaning operation of the dust suction device to be dissipated or deflected by reflection.

Background

Dust is often generated when working with power tools, such as drills, cutters or angle mills or slot mills, which may be harmful to human health, especially if dust is inhaled. The prior art discloses dust hoods by means of which the working means of such power tools, such as drills, chisels or cutting disks, can be covered. Such dust cages are preferably used to collect dust generated during operation using the power tool. The dust cage may preferably be connected to a dust suction device or a dust remover so that dust collected in the dust cage can be extracted by the dust suction device or the dust remover. This is usually done by generating a vacuum which is transmitted to the dust cage via a suction hose. For the connection of the dust suction device or the dust catcher, the dust hood preferably has a suction hose connection in the region where the suction hose opens into the dust hood. For the purposes of the present invention, this region of the dust cage is preferably referred to as the extraction region.

In the case of conventional dust cages known from the prior art, dust leakage may occur. Such dust leakage is known, for example, when a conventional dust cage is connected to a slot mill. For the purposes of the present invention, the slot milling cutter is preferably designed to form a slot, for example, in a wall, so as to be able to lay a wire in a "knock-out" slot. A problem with the occurrence of leaks in the area where dust can pass through a conventional dust cage into the outside, that is to say into the surroundings, is that the corresponding certification standards specify lower limits for dust emissions, which are difficult, if not impossible, to observe with the use of an unsealed dust cage. In particular, the leakage may disadvantageously result in an inability to keep sufficient dust away from the operator of the power tool, with the result that the dust is inhaled by the operator and may enter his or her respiratory tract. Dust typically comprises dust particles which may be small enough to enter the lungs, for example. Other dust particles may be harmful to health or carcinogenic.

Especially the dust escape observed in conventional dust cages during filter cleaning. During filter cleaning, the filter of the dust collector or dust suction 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 of the vacuum generation in the dust aspirator, so that the pressure conditions in the dust aspirator change for a short time, resulting in a pressure surge acting on the filter. The filter cake can be loosened or released from the filter by pressure surges. In other cases, a reverse gas flow may be actively blown through the filter, with the result that the filter cake is released from the filter. These measures may be performed once or may be repeated during the cleaning cycle. For example, the cleaning cycle of the dust suction device may include three cleaning gushes. The implementation of the cleaning cycle can be initiated automatically, for example at regular intervals, or controlled as required.

Since during the cleaning operation (pressure) surges are frequently applied to the filter, this operation is also preferably referred to for the purposes of the present invention as knock-out operation. This knock-out operation often causes blow-back in the suction hose or inside the dust cage, which in the case of conventional dust cages known from the prior art may undesirably lead to the discharge of dust particles.

Disclosure of Invention

The present invention is based on the object of overcoming the above-mentioned drawbacks of the prior art and of providing a dust cage for a power tool which, on the one hand, is designed to be particularly sealed and, on the other hand, makes it possible to effectively prevent situations in which dust can enter the respiratory tract of the operator of the power tool. Furthermore, it is intended to use the dust cage provided to prevent dust agglomerates from being discharged when the filter is cleaned.

This object is achieved by the subject matter of independent claim 1. Advantageous embodiments of the subject matter of the independent claims can be found in the dependent claims.

According to the invention, a dust hood for a power tool is provided, wherein the dust hood comprises an extraction region in which a suction hose from a dust suction device opens into the dust hood. The dust hood is characterized in that the dust hood has a curvature in the extraction area, wherein the curvature is designed to attenuate an impinging surge flow from the dust suction device and conveyed through the suction hose to the inner area of the dust hood. In particular, the preferably inwardly formed curved portion of the dust cup wall ensures that the at least one cleaning gush is deflected and prevented from penetrating from the extraction space into the interior of the dust cup.

In the context of the present invention, a defined curved portion on an inner wall of the dust cage is proposed, which curved portion is particularly arranged in an extraction area of the dust cage. The curved portion by its characteristic configuration advantageously ensures that possible impact shocks or pressure waves, which may arise during filter cleaning of the dust suction device, are dissipated and/or deflected inside the dust cage, which is preferably connected to the dust suction device. Preferably, a dust boot, which can preferably be connected to the power tool, is connected to the dust suction device, as a result of which dust generated when working with the power tool can be extracted by the dust suction device. In this case, pressure waves and/or surge currents generated during a filter cleaning operation of the dust suction device can be conveyed via the suction hose to the dust hood. The extraction of dust and dust particles is preferably performed by generating a vacuum by a dust suction device, which vacuum is transferred to the dust hood by means of a suction hose connecting the dust hood to the dust suction device. Therefore, a vacuum is preferably also present in the dust cage.

The deflection of the impact surge, which can be achieved by the curved portion of the dust hood, preferably generates a counter-impact, by which advantageously it is possible to prevent the occurrence of a situation in which the vacuum in the inner region of the dust hood, which is generated by the dust suction device, is broken during the cleaning of the filter. This also allows dust generated during filter cleaning when working with the power tool to be collected in the dust cage 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 conventional dust hoods without curved sections on the inner wall of the extraction region, it has hitherto easily occurred that the impact gushes generated during filter cleaning penetrate into the working components of the power tool and undesirably lead to an outflow of dust particles. In other words, what may occur in the case of a conventional dust cage is: due to the impact gushes and pressure waves generated during the cleaning of the filter, dust particles are expelled from the dust cage, as a result of which the released dust may enter the respiratory tract of the operator. The dust mass is generated in particular by the fact that the vacuum in the dust cage is broken, which is advantageously prevented in the case of the dust cage proposed according to the invention by the provision of a defined curvature. The curved portion advantageously ensures that the impinging stream is reflected on the wall in which the curved portion is present. In particular, an impact current striking a curved wall may be conceptually broken down into a plurality of individual currents extending substantially in parallel. Preferably, these notional individual impact gushes are reflected on the curved wall of the dust cage in such a way that they return into the extraction area and at least partially disappear or attenuate each other. As a result, the propagation of surge currents into the interior region of the dust cage and the breaking of the vacuum therein are advantageously effectively prevented.

Surprisingly, the provision of the curved portion not only ensures attenuation or disappearance of the reflected impact gush. It has been shown that reflected impacts can also advantageously attenuate and/or eliminate newly arriving filter cleaning gusts. This may be particularly advantageous when the filter cleaning process of the dust suction device to which the power tool is connected comprises a plurality of bursts or compressed air surges which arrive at the dust hood in succession. Advantageously, the curved portion of the proposed dust cage allows to attenuate or to eliminate both already reflected and newly arriving impacts and/or compressed air gushes, which the filter of the dust suction device uses for cleaning or is blown through to release the filter cake. This attenuation is illustrated in particular by the arrows in the lower region of fig. 2. In particular, the newly arriving impact surge flow generates a vortex through the reflected impact surge flow when passing through the extraction space of the dust cage in such a way that further penetration of the impact surge flow into the interior of the dust cage, which is separated from the extraction space by a baffle, is effectively avoided. This advantageously ensures that the vacuum used for extracting dust inside the dust cage is not adversely affected.

It is preferred for the purpose of the invention that the curvature inside the dust cage is defined by a height to diameter ratio. For the purposes of the present invention, the term "diameter of the curved portion" preferably describes the distance between two points at which the curved portion starts or ends on an otherwise substantially smooth wall. In other words, two points between which the diameter exists as a length may be understood as a start point and an end point of the curved portion. The diameter of the curved portion may be in the range of, for example, 15mm 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 that protrudes above the otherwise substantially smooth wall of the dust cage. In other words, the height may be understood as the distance between the further substantially smooth wall and the highest point of the curved portion. The height of the curved portion may be in the range of, for example, 5mm to 25 mm. The height to diameter ratio may be in the range of, for example, 0.14 to 1.7, with particular values less than 1 being preferred. In other words, it is preferred for the purposes of the present invention that the diameter of the curved portion be greater than its height, although the height of the curved portion may be greater than the diameter in alternative embodiments. In determining the height to diameter ratio, the value of the height of the bend is preferably set relative to the value of the diameter of the bend. Preferably, these values are divisible with each other, 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. One possible configuration of the curved portion is shown in the drawings. For the purposes of the present invention, it is particularly preferred that the curved portion is formed inwards, that is to say inwards, into the extraction space of the dust cage. In this case, the curved portion may be particularly considered as an indentation. However, it may also be preferable that the bent portion is formed outward.

The dust generated during operation with the power tool may include dust particles of different sizes or different diameters and geometries. For example, very small particles that are hardly visible to the human eye may be a constituent of the dust. However, it may also occur that when working with a power tool, for example during wall or masonry working, relatively large processed particles are produced which are initially too large to be transported into the collection container of the dust suction device via the suction hose connecting the dust cage to the dust suction device. Such relatively large processed particles may not be initially extracted by the dust extraction device.

In order to be able to further process such processed coarse particles, and in particular to be able to extract them with a dust suction device, the dust cage may comprise a baffle, advantageously so that a coarse filtering action can be produced by the baffle. This prevents major breakages, which may occur during operation of the power tool and which may enter the inner region of the dust cage, the machined product causing blockages in the suction area. In contrast, the arrangement of the baffle advantageously ensures that the coarse particles produced bounce off the baffle plate and fall back into the working area of the power tool or into the dust hood interior, where they are further comminuted by the working means, for example a cutting disk, until the comminuted particles fit through the opening of the hose area and can be conveyed by the suction hose into the dust suction device.

It is known that the working elements of power tools may break under high mechanical loads. Such an undesired breakage may constitute a risk for the operator of the power tool, for example when he or she is hit by a broken piece of the working device. The risk of injury is particularly caused by sharp, pointed or sharp-edged fragments, which may lead to cuts. For the purposes of the present invention, it is preferred that the individual wall region of the dust hood is of double-walled design, wherein the preferred double-walled region of the dust hood wall can advantageously absorb the kinetic energy of the fragmented pieces in the event of a possible fracture of the power tool working means, as a result of which the operator of the power tool is particularly effectively protected from injury or the influence of fragments. The working means of the power tool may in particular be formed by a cutting disc or a cutting disc, for example when the working device is a cutter or an angle grinder. For the purposes of the present invention, it is preferred that in particular those regions of the dust hood wall which may come into contact with the chips produced in the event of a fracture of the cutting disk or cutting disk have a double-walled design, that is to say a reinforced design, in order to protect the operator of the power tool from injury.

It may also be preferred for the purposes of the present invention that the wall of the dust cage is of a continuous double-walled design. For example, a continuous double-walled closure of the dust cage may be advantageous for safety reasons. It may also be preferred that the wall is of at least double-walled design, wherein the wall may completely or partially have more than two layers or be formed by more than two layers or more than two separate walls. In the case of a double-walled or multi-walled configuration of the walls or wall regions, the regions between the individual walls can be of hollow design or filled with a filler. An example of a filling material that can be used is a lightweight material to keep the weight of the dust cage low. For example, a plastic foam material may be used as a filler between the individual walls of the dust cage. The individual walls of the dust cage preferably have a thickness in the range of 0.1mm to 3mm, with a wall thickness in the range of 2mm to 3mm being particularly preferred. In summary, the dust boot wall preferably has a wall thickness of at least 5 mm.

The dust cage preferably comprises an electrically conductive base material. In other words, it is preferred that the dust cage or its walls are formed of an electrically conductive material. It is preferred, in particular, that the inner side of the proposed dust cage has an electrically conductive base material. The provision of an electrically conductive base material advantageously ensures that electrostatic charges which may be generated inside the dust cage as a result of the normally dry dust are transferred via the dust cage to the suction hose. In this way, as a particular advantage of the invention, it is ensured that the electrostatic charge is dissipated via the dust suction device. For these purposes, it is particularly preferred that the dust discharge is configured to be completely coherent for electrostatic conduction. In particular, dust emissions include areas from the source of the dust to its storage in the dust container. In one exemplary embodiment of the invention, it is preferred that the dust hood comprises a wall made of an electrically conductive material, wherein the material transfers electrostatic charges, which may be generated by dry dust, via the dust hood to the suction hose, so that dissipation via the dust suction device can advantageously be ensured. Preferably, the entire dust discharge from the source to the storage of the dust in the dust container is configured for coherent electrostatic conduction.

For example, an electrically conductive or conductive plastic can be used as a base material for the dust cage or for the walls and components of the dust cage. It may also be preferred for the purposes of the present invention that the conductive additive is mixed with the primary particles used for producing the dust cage or its constituent parts, whereby an electrostatically conductive material is advantageously obtained. For example, metal chips may be mixed as an additive with the plastic used for producing the dust cage or its component parts.

An electrostatic charge within the dust cage material is generated, for example due to friction between dust fragments or dust particles and the plastic material of the dust cage, preferably during operation of the power tool or during dust formation. Such charging occurs in particular when the dust is very dry, that is to say, for example, in summer or during long drying periods. In the case of very high electrostatic charging, if the charge is not dissipated in a targeted and conscious manner via a corresponding ground, an undesired spontaneous discharge via the user may occur. To this end, the transitions between the individual components of the dust cage are also preferably designed to be electrically conductive to allow charge dissipation.

Preferably, providing the dust cage or components thereof with an electrostatically conductive material allows for charge equalization inside the power tool. This is particularly advantageous when charges of different signs are collected at different regions of the tool and thus form an electric field. The preferred electrically conductive material of the dust cage can provide a charge equalization possibility here, wherein surplus electrons can flow out of one region of the tool and can compensate for an insufficient electron in another region of the tool. Avoiding uncontrolled discharge or charge equalization operations also makes it possible, in particular, to significantly reduce flying sparks and reduce the risk of fire during power tool operation.

For the purposes of the present invention, it is preferred that the inner region 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 interior region of the dust hood comprises in particular the region of the preferably hollow interior of the dust hood, in which dust is present as a result of the operation of the power tool. For the purposes of the present invention, this region may also preferably be referred to as the working region of the power tool or working device. For example, the working tool may be a cutter or an angle grinder including a cutting disk or a cutting disk as a working device. For the purposes of the present invention, it is particularly preferred that the interior of the dust hood comprises a working area of the working means, in which case in a preferred configuration of the invention the working means can be a cutting disk or a cutting disk. The interior of the dust hood is designed to be flow-or aerodynamically uniform, in particular to ensure a particularly dust-free operation of the power tool. It is very particularly preferred for the purposes of the present invention that the inner walls of the dust cage, which preferably define the interior of the dust cage, are designed in particular to be flow-dynamically or aerodynamically uniform. Designing the interior of the dust cage to be flow-or aerodynamically uniform can be achieved, for example, by providing a particularly smooth inner wall. It may also be preferred for the purposes of the present invention that the geometry or spatial configuration of the interior of the dust cage causes or contributes to the formation of an interior of the dust cage having a uniform design in terms of flow dynamics or aerodynamics.

In a preferred embodiment of the invention, the dust cage comprises a baffle as abrasive wear protection or temperature protection. For the purposes of the present invention, it is preferred that the baffle is arranged on the front side of the dust deflector. For the purposes of the present invention, the dust deflector preferably constitutes a device for improving the feeding or deflection of dust particles into the extraction region of the dust hood. The shield may also be used to protect the plastic part of the dust cage from sparks or flying sparks if the shield comprises metal or metal alloy or is formed from a metal grid. The baffles are preferably designed to have high wear resistance to withstand high mechanical and/or thermal loads caused by dust particles and/or sparks. The provision of a baffle as a protection for the plastic component of the dust cage advantageously results in a significant extension of the service life of the proposed dust cage. The baffle also preferably absorbs thermal energy, i.e. heat, and thereby ensures cooling of the interior of the dust cage by virtue of its good thermal conductivity. The baffle can in particular be formed by a baffle plate, which is preferably arranged on the inside of the dust deflector. In one embodiment of the invention, it may be preferred that the baffle is formed by a grid, which comprises or is formed by metal, for example.

The dust cage is preferably formed by two mutually corresponding halves which together form the basic body of the dust cage. The fastening of the baffle is preferably formed by clamping the two dust cage halves. It is entirely surprising that the provision of a baffle in the dust deflector area inside the dust cage can provide a combination of additional abrasive wear protection and further fracture protection. A further advantage of the baffle provided lies in the fact that: the baffle can be used to achieve a coarse filtration of the dust, wherein the coarse filtration in particular allows processed larger particles, which initially cannot be extracted by the suction hose of the dust suction device, to be returned to the interior of the dust cage so that these larger particles can be further comminuted by the cutting disc of the power tool. Comminution produces processed smaller particles that are advantageously sized to allow conditions in which the comminuted processed particles can pass through a suction hose and be extracted by a dust suction device.

Drawings

Further advantages can be found in the following description of the figures. The figures, description and claims contain many combinations of features. It will also be convenient for those skilled in the art to consider these features separately and combine them to produce useful further combinations.

In the drawings, the same components and the same types of components are denoted by the same reference numerals. In the drawings:

figure 1 shows a cross-sectional illustration of a preferred configuration of a dust cage;

figure 2 shows a cross-sectional illustration of a preferred embodiment of the extraction area of the dust cage;

FIG. 3 shows a view of a preferred configuration of the baffle; and

figure 4 shows a view of a preferred embodiment of the dust cage assembly.

Detailed Description

Fig. 1 shows a sectional illustration of a preferred configuration of the proposed dust cage (1). In particular, fig. 1 shows a curved portion (5) preferably present on the wall of the dust cage (1). For the purposes of the invention, it is particularly preferred if the curved section (5) is arranged on the wall opposite the outlet of the suction hose (4). The region of the suction hose (4) opening into the dust hood (1) is preferably also referred to as the extraction region (3) of the dust hood (1). The suction hose (4) preferably connects the dust cage (1) to a dust suction device (not shown), wherein preferably both a vacuum, which is generated by the dust suction device to suck in dust, and an impact surge, which is generated during filter cleaning, are transferred from the dust suction device to the dust cage (1) by means of the suction hose (4). The impact surge generated by the dust suction device during the filter cleaning and guided by the suction hose (4) into the dust hood (1) can for example form an impact pressure jet which, in the case of the proposed dust hood (1), first strikes a curved region (5) of the dust hood wall. Due to the specific configuration of the curved portion (5), the impinging pressure jets are preferably split and turned or deflected in different directions. In particular, the reflected impact gushes are superimposed in a curved region (5) of the dust hood (1), as a result of which the reflected impact gushes are advantageously attenuated or eliminated from each other.

A particular advantage of the invention achieved by this attenuation or disappearance of the reflected surge is that the surge does not penetrate further into the interior (6) of the dust cage (1). This advantageously leads to the following fact: a vacuum can also be maintained in the interior (6) of the dust hood (1) during the cleaning of the filter of the dust suction device. This overcomes the drawbacks of conventional dust hoods, which often eject dust particle clusters from the respective openings during the cleaning of the filter of the dust suction device. Maintaining a vacuum in the interior (6) of the proposed dust cage (1) advantageously avoids such a release of dust particles, as a result of which the respiratory tract load of an operator of the power tool (2, not shown) can be significantly reduced by means of the invention.

While maintaining the vacuum during filter cleaning, dust generated during this period due to operation of the power tool (2) can be advantageously collected into the interior (6) of the dust cage (1). After the filter has been cleaned, the dust suction device can again generate a vacuum, which can be transferred from the suction hose (4) to the dust cage (1). In this way, dust particles collected in the dust cage (1) during filter cleaning can be extracted by the suction hose (4) after filter cleaning and stored in the collection container of the dust suction device.

Fig. 1 furthermore shows various regions of the wall (7) of the dust cage (1) which is at least partially of double-walled design. Thus, the area of the wall (7) of the dust cage (1) has a more stable design and provides better protection for the operator of the power tool (2), for example when the working means of the power tool (2) are damaged or broken. The debris occurring in the event of such damage is absorbed by the preferably double-walled region of the dust hood wall (7), whereby the escape of debris from the dust hood (1) can advantageously be avoided. Furthermore, in particular the outer wall of the dust hood wall (7) having an at least partially double wall can have elastic properties which enable the double-walled wall region (7) to withstand deformation forces, for example in the event of a drop of the dust hood (1) or of the power tool (2). As a result, the double-walled wall region (7) advantageously also ensures improved fall protection for the proposed dust hood (1) or power tool (2).

For the purposes of the present invention, it is preferred that the device chain of the inner dust region 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 ground conductor. In this way, it is advantageously possible to dissipate the charge in both mains-powered and battery-powered power tools (2).

In the preferred embodiment of the invention illustrated in fig. 1, a baffle (8) is also depicted. The baffle (8) in the exemplary embodiment shown in fig. 1 is designed as a metal grid. The metal grid (8) makes it possible to prevent relatively large dust or stone particles, which are also preferably referred to as processed particles for the purposes of the present invention, from entering the extraction area (3) of the dust cage (1). In other words, the baffle (8) marks a boundary between an interior (6) of the dust cage (1) present in a lower region of the dust cage (1) and an extraction region (3) of the dust cage (1) present in an upper region of the dust cage (1). The baffle (8) preferably ensures that relatively large dust or stone particles are thrown back into the interior (6) of the dust cage (1), where they can be crushed again or further when they enter the working area of the working means of the power tool (2). If the diameter of the dust particles or stone particles after reprocessing through the working means of the power tool (2) fits through the opening of the baffle (8), the processed particles enter the extraction region (3) of the dust cage (1) and are extracted there by the dust suction device. For this purpose, the particles are first sucked into a suction hose (4) and then into a collection container of the dust suction device.

Fig. 2 shows a cross-sectional illustration of a preferred embodiment of the extraction area (3) of the dust cage (1). In this case, the upper region of the dust hood (1) into which the suction hose (4) of the dust suction device opens is preferably concerned. A curved portion (5) is preferably arranged opposite this opening of the suction hose (4) into the dust hood (1), which curved portion advantageously causes a disruption and/or deflection of the surge stream of the dust suction device. It is preferred for the purpose of the invention that the curved portion (5) produces a refraction of the impact pressure surge in such a way that it can no longer enter the interior (6) of the dust cage (1) to be damped. In the exemplary embodiment of the invention illustrated in fig. 2, the curved portion (5) constitutes an indentation, that is to say a concave indentation in that region of the wall of the dust cage (1) which is opposite the opening of the suction hose (4). In particular, the indentation for the purpose of the invention preferably constitutes an inward bow, that is to say that in a certain area there is a curved portion into the interior of the dust cage (1). The impact gush output by the dust suction device during filter cleaning will preferably move further linearly when leaving the suction hose (4) and thereby hit the dust boot wall at a certain angle defined by the contour of the curved wall area. For the purpose of the present invention, the term "curved wall area" preferably denotes a wall area of the dust cage (1) comprising the curved portion (5) of the dust cage wall.

The impact gush is reflected by the wall of the dust cage (1) according to the impact angle and enters the extraction area (3) of the dust cage (1). The wall region of the dust hood (1) opposite the opening of the suction hose (4), preferably also comprising the curved portion (5), is particularly configured such that the reflected impact gush disappears precisely or at least greatly attenuated by means of a superposition effect. Therefore, the impact cannot further penetrate into the interior (6) of the dust collection cover (1). This surprisingly leads to the following fact: the destruction of the vacuum in the interior (6) of the dust hood (1) can be effectively avoided, as a result of which, during filter cleaning, in particular no dust particles are ejected or blown out of the interior of the proposed dust hood (1) to the surroundings outside the power tool (2). The curved portion (5) in the dust boot wall causes in particular the following facts: the reflected impact gushes are virtually fanned out and dispersed into different directions, wherein, taking into account the small available space in the extraction area (3) of the dust cage (1), the reflected impact gushes are advantageously superimposed in such a way that they are substantially attenuated or completely eliminated. Thus, essentially parallel impact gushes that first hit the dust hood wall are reflected into the entire extraction area (3) of the dust hood (1), where they are attenuated against each other. This reflection or refraction of the impinging current is shown in particular in the lower part of fig. 2. Here, the black arrows preferably represent the impact gushes conceptually decomposed into individual impact gushes. These individual impact gushes generated by the dust suction device during filter cleaning are refracted or reflected on the curved dust hood wall and deflected into the extraction area (3) of the dust hood (1). The notional individual impacts of reflection or refraction are preferably indicated by white arrows at the bottom of fig. 2.

Figure 3 shows a view of a preferred embodiment of a dust cage assembly. Fig. 3 shows a preferred embodiment of the dust cage (1) proposed in particular. Fig. 3 shows in particular the upper region of the dust cage (1) formed by the extraction region (3). A suction hose (4) connecting the dust cage (1) to the dust suction device opens into the extraction area (3). The interior (6) of the dust cage (1) is present in the lower region of the dust cage (1), which interior is separated from the extraction region (3) by a baffle (8; see fig. 4).

Fig. 4 shows a view of a preferred configuration of the baffle (8) of the proposed dust cage (1). Located above the baffle (8), which in the depicted exemplary embodiment of the invention is designed as a metal grid, is the extraction area (3) of the dust cage (1) with the curved portion (5). The curved portion (5) or the curved wall region of the dust hood (1) is preferably arranged opposite the opening of a suction hose (4) by which the dust hood (1) can be connected to a dust suction device. Located below the metal grid (8) is an inner region (6) of the dust cage (1) in which working means, for example a power tool (2), can be present.

It is preferred for the purpose of the present invention that the dust cage (1) comprises two shells or halves forming the basic body of the dust cage (1). The two housings hold and sandwich a metal grid (8). Thus, larger processed sheet-like fragments or processed particles are retained and do not clog the suction hose (4). This makes it possible to safely work with the power tool (2) or the dust suction device without interruption due to a clogged hose line. Furthermore, the provision of the baffle (8) reduces the occurrence of dust agglomerates which may occur as an adverse consequence when the extraction line is blocked.

List of reference numerals

1 dust collecting hood

2 Power tool

3 extracting regions

4 suction hose

5 curved part

6 inner area of dust collecting hood

7 double-walled dust hood wall

8 baffle