EP2326465B1 - Power tool - Google Patents

Description

State of the art

The invention relates to a power tool according to the preamble of claim 1, and of a power tool filter device according to the preamble of claim 12. It is already a power tool with a machine housing and a ventilation unit, which is used to cool a motor unit enclosed by the engine housing and / or Electronic unit is provided by suction of a cooling air flow, known, wherein the ventilation unit comprises a deflection unit. Such a power tool according to the preamble of claim 1 is disclosed in DE102006000162 ,

Advantages of the invention

The invention relates to a power tool with a machine housing and a ventilation unit, which is provided for cooling a motor unit and / or electronics unit enclosed by the machine housing and which has a deflection unit.

It is proposed that the deflection unit has at least one deflection channel, which is provided by means of a deflection of the cooling air flow to a separation of dirt particles and air of the cooling air flow. In this context, "intended" should be understood to mean in particular specially equipped and / or specially designed. The ventilation unit preferably has a fan for suction of the cooling air flow or for generation of a suction force during operation of the power tool. Furthermore, a "deflection unit" is to be understood as meaning, in particular, a unit which is preferably in the area and / or within a ventilation duct the ventilation unit is arranged and in particular due to the deflection of the cooling air flow to a separation, in particular a mass-dependent separation between dust and / or dirt particles and air, in particular gaseous particles and / or molecules of the air leads. In this case, a "deflection channel" is to be understood as meaning, in particular, a channel which is provided for targeted guidance of the cooling air flow and deflects the cooling air flow in an intended direction, so that a scattering of particles of the cooling air flow, in particular into a region surrounding the channel along its longitudinal extent Preferably, the deflection channel is shielded from further components and / or regions of the electrical device by a separate channel housing., Preferably a force, in particular a centrifugal force and / or a gravitational force, etc. acts on the particles of the cooling air flow due to the deflection The cooling air flow is composed of air and dust and / or dirt particles entrained in the air by a suction force of the ventilation unit Dust and / or dirt particles are separated from air in the cooling air flow, so that a nearly dust-free and / or dirt-free cooling air for cooling the motor unit and / or the electronic unit is available during operation of the power tool. In addition, an undesired emission of components and / or elements of the motor unit and / or the electronics unit, such as a motor winding and / or insulation, can advantageously be reduced or prevented, and thus a service life of the motor unit and / or the electronics unit can advantageously be extended or Failure of the components and / or the power tool can be prevented. Furthermore, can be advantageously dispensed with additional components, such as a dust and / or dirt filter, and thus a maintenance of the ventilation unit can be minimized.

Furthermore, it is proposed that the deflection channel has at least one curved deflection channel section. In this context, the term "bent" should in particular be understood to mean that the deflection channel has a curved deflection channel section, preferably with a continuous change in direction. The Umlenkkanalabschnitt can hereby ring-like, elliptical, U-shaped, etc. be formed. In this case, a centrifugal force can be structurally simple acting on particles of the cooling air flow guided in the deflection channel section, thereby achieving mass-dependent, spatial separation of the particles, in particular separation of the dust and / or dirt particles from the air, the heavy dust and / or dirt particles deflected in an outer region of the bent Umlenkkanalabschnitts can be and the air can flow through the Umlenkkanalabschnitt in an inner region.

Particularly advantageously, the deflection channel has at least one spiral deflection channel section, as a result of which a particularly space-saving and compact deflection unit can be achieved. In addition, a particularly effective separation of heavy and light particles of the cooling air flow can be achieved by a radius of the spiral Umlenkkanalabschnitts preferably decreases along the flow direction and thus a centrifugal force acting on the particles can be advantageously increased. The deflection channel can also be conically tapered along the direction of flow and / or be helical and / or have further forms that appear appropriate to the person skilled in the art.

It is further proposed that the deflection channel has a plurality of Umlenkkanalabschnitten, wherein in at least one Umlenkkanalabschnitt the cooling air flow has a movement direction which is substantially opposite to a direction of movement of adjacent Umlenkkanalabschnitten. In this context, a "plurality" should be understood to mean, in particular, a number of at least two or more than two. In addition, "substantially oppositely" is to be understood in particular as meaning that one direction is at an angle to a reference direction of 180 ° with a deviation of ± 20 °, advantageously with a maximum deviation of ± 8 ° and particularly preferably with a maximum deviation of ± 3 °. In this case, it is advantageously possible to achieve efficient separation of the heavy dust and / or dirt particles from the air by redirecting the cooling air flow several times. If, in addition, at least one deflection channel section has a flow direction oriented counter to gravity, a structurally simple, in particular mass-dependent, separation of the heavy particles from the cooling air flow can be achieved, and this can be particularly advantageous in particular with stationary power tools.

It can be achieved an advantageous accumulation of deposited dirt particles and in particular fouling of an interior of the power tool can be prevented if at least one of Umlenkkanalabschnitte has a chamber which is provided for a deposition of the dirt particles. In this context, a "chamber" should be understood to mean in particular a closed space with a housing, wherein the closed space preferably through the housing, in particular of a separate, separate from another Components and / or elements of the power tool is formed, is separated from other components and / or areas of the power tool.

Particularly advantageously, the deflection unit has at least one feed channel, which is designed as a dip tube. In this context, a supply channel is to be understood as meaning, in particular, a channel which is provided for selectively guiding the cooling air flow cleaned of dirt particles during operation of the power tool in the direction of the motor unit and / or the electronics unit and which additionally supplies the cleaned cooling air flow of further components and / or Shields areas of the power tool. In addition, a "dip tube" is to be understood in particular as meaning a tube and / or a channel which extends at least partially into the deflection unit, in particular into a separation space or a deflection region of the deflection unit. In this case, targeted removal of a cooling air stream cleaned of dirt particles can be achieved and a particularly space-saving design of the deflection unit can be achieved.

In addition, advantageously, a rotation of the cooling air flow, in particular around the dip tube, be increased while an effect of centrifugal force for the separation of massive particles and low-mass particles in the cooling air flow can be improved if the deflection channel is arranged in a circumferential direction at least partially around the dip tube.

Furthermore, it is proposed that the ventilation unit has at least one intake passage and at least one feed passage and a flow direction of the cooling air flow in the intake passage is substantially opposite to a flow direction of the cooling air flow of the feed passage. In this case, a structurally simple arrangement of the deflection unit can be achieved and, in the process, a compactness of the power tool can advantageously be maintained.

In an advantageous development of the invention, it is proposed that the deflecting unit has at least one outlet opening in at least one deflection area, which is provided for escape of the dirt particles of the cooling air flow, whereby an effective separation of the heavy dust and / or dirt particles from the cooling air flow in the separation area or In the deflection region of air can be achieved. Preferably, the deflection unit has, in addition to the outlet opening, an additional main outlet opening, which is provided for outflow of the purified cooling air flow.

It is also proposed that the outlet opening is arranged on an outer wall of a bent Umlenkkanalabschnitts the Umlenkkanals, whereby a structurally simple deposition of heavy dust and / or dirt particles due to the force acting on the dust and / or dirt particles centrifugal force can be achieved.

If the ventilation unit has at least one outlet channel which branches off from the deflection channel at the outlet opening, undesired contamination of an interior of the electric tool can advantageously be prevented. In this context, an "outlet channel" should be understood to mean, in particular, a channel for discharging, in particular, dust and / or dirt particles of the cooling air flow, the channel preferably having a housing formed separately from an inner wall of a machine housing which seals the dust and / or dust Dirt particles before other components of the power tool, in particular a motor unit, etc., shields. The outlet channel can also open into a collecting container for dust and / or dirt and / or open particularly advantageous via an opening of the outlet channel, which is arranged in the machine housing, into the open. In addition, a valve with a passage direction, which allows blowing out of the heavy dust and / or dirt particles may be arranged in the outlet channel, so that an undesired suction of an air flow through the outlet channel can be advantageously prevented.

Furthermore, the invention according to claim 12 is based on a power tool filter device with at least one filter unit which has at least one filter element. Such a power tool filter device according to the preamble of claim 12 is disclosed in DE4342484 , In this case, it is proposed that the filter unit has a dedusting unit which is provided for dedusting the filter element. In this context, a "filter element" should be understood to mean, in particular, an element which is provided as a volume of air for separating dust particles and / or processing residues, in particular from a cooling air flow due to a larger volume of the dust particles and / or the processing residues. In this case, the filter unit is preferably arranged in the region of an intake opening of a ventilation unit. As a result of the configuration according to the invention, a high cooling capacity of the filter device can advantageously be maintained and, in addition, a sealing of filter pores of the filter element can at least be reduced and / or prevented. Furthermore, in this case a cost-reduced use with low maintenance of the filter device can be achieved by a frequency of replacement of the filter element can be reduced.

Furthermore, it is proposed that the dedusting unit has at least one dedusting element which abuts against the filter element in at least one operating position, whereby a particularly compact arrangement of the dedusting unit within the filter device can be achieved in a structurally simple manner. In addition, the dedusting element may be coupled to a switch-on element of the power tool, so that the filter element is dedusted when the power tool is switched on and / or switched off, and / or the dedusting element may be provided with a separate actuating element which is arranged directly on the filter unit ,

If the dedusting unit has at least one spring element which is provided for dedusting movement of the dedusting element, this can be done by means of a simple movement of the dedusting element in only one direction, such as by pressing, pulling, etc. by an operator, a dedusting movement due to a spring force of the Spring element can be achieved structurally simple in an opposite direction. The spring element can be formed by any spring element that appears appropriate to the person skilled in the art. However, the spring element is particularly advantageously formed by a helical spring.

drawing

Further advantages emerge from the following description of the drawing. In the drawings, embodiments of the invention are shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

Fig. 1

eine Schnittdarstellung eines Elektrowerkzeugs mit einer Lüftungseinheit und einer Schmutzabscheidereinheit,

Fig. 2

einen Fliehkraftabscheider in Form einer Schneckenabscheidereinheit in einer schematischen Schnittdarstellung,

Fig. 3

das Elektrowerkzeug mit einer alternativen Ausgestaltung eines Fliehkraftabscheiders in Form einer u-förmigen Umlenkeinheit in einer schematischen Schnittdarstellung,

Fig. 4

eine Detaildarstellung der u-förmigen Umlenkeinheit aus Figur 3,

Fig. 5

eine alternativ ausgebildete Umlenkeinheit in einem schematischen Teilschnitt,

Fig. 6

das Elektrowerkzeug mit einer alternativen Ausgestaltung eines Fliehkraftabscheiders in Form eines Zyklonabscheiders in einer schematischen Schnittdarstellung,

Fig. 7

eine von einem Gravitationsabscheider gebildete Schmutzabscheidereinheit in einer schematischen Darstellung,

Fig. 8

eine Filtervorrichtung für das Elektrowerkzeug mit einem Filterelement und einem Entstaubelement in einer schematischen Darstellung,

Fig. 9

eine schematische Teilansicht der Filtervorrichtung aus Figur 8 mit einem Federelement in einer ersten Betriebsposition und

Fig. 10

eine schematische Teilansicht der Filtervorrichtung aus Figur 8 mit dem Federelement in einer zweiten Betriebsposition.

Show it:

Fig. 1

a sectional view of a power tool with a ventilation unit and a dirt separator unit,

Fig. 2

a centrifugal separator in the form of a Schneckenabscheidereinheit in a schematic sectional view,

Fig. 3

the power tool with an alternative embodiment of a centrifugal separator in the form of a U-shaped deflection unit in a schematic sectional view,

Fig. 4

a detailed representation of the U-shaped deflection unit FIG. 3 .

Fig. 5

an alternatively formed deflecting unit in a schematic partial section,

Fig. 6

the power tool with an alternative embodiment of a centrifugal separator in the form of a cyclone separator in a schematic sectional view,

Fig. 7

a dirt separator unit formed by a gravitational separator in a schematic representation,

Fig. 8

a filter device for the power tool with a filter element and a dedusting in a schematic representation,

Fig. 9

a schematic partial view of the filter device FIG. 8 with a spring element in a first operating position and

Fig. 10

a schematic partial view of the filter device FIG. 8 with the spring element in a second operating position.

Description of the embodiments

In FIG. 1 a power tool 10a formed by an angle grinder is shown in a schematic section. The power tool 10a has a machine housing 12a, which comprises a gear housing 80a and a motor housing 82a, wherein the gear housing 80a and the motor housing 82a are arranged successively along a main extension direction 84a of the electric tool 10a. In addition, the power tool 10a has a motor unit 16a and an electronics unit 18a, which are enclosed by the machine housing 12a and the motor housing 82a, respectively. For cooling the motor unit 16a and / or the electronics unit 18a during operation of the power tool 10a, the power tool 10a has a ventilation unit 14a, which is provided for sucking in a cooling air flow 20a. The ventilation unit 14a is arranged in a region of the power tool 10a enclosed by the motor housing 82a. In addition, the power tool 10a or the motor housing 82a on suction openings 86a, is sucked through the air during operation of the ventilation unit 14a, and not shown exhaust ports through which the air is blown out after a cooling process.

The ventilation unit 14a comprises a fan wheel 88a and a dirt separator unit 90a. The fan 88a is provided to generate a suction force in the operation of the power tool 10a, and sucks the cooling air flow 20a through the suction ports 86a. The fan 88a is for this purpose arranged on a motor shaft 92a of the motor unit 16a and connected in rotation therewith. Along a flow direction 52a of the cooling air flow 20a, the dirt separator unit 90a is arranged in front of the motor unit 16a and the electronic unit 18a and these are arranged in front of the fan wheel 88a. Along the main extension direction 84a of the power tool 10a, the suction openings 86a are arranged in front of the dirt separator unit 90a.

The dirt separator unit 90a is in FIG. 2 shown in detail and formed by a helical centrifugal 94a. Furthermore, the dirt separator unit 90a has a deflection unit 22a, which is provided for deflecting the cooling air flow 20a, which leads to a mass-dependent separation of heavy dust and / or dirt particles 26a and air 28a. The deflection unit 22a has a deflection channel 24a, a suction region 96a and a feed channel 44a, wherein along the flow direction 52a the deflection channel 24a is arranged between the suction region 96a and the feed channel 44a. The feed channel 44a is hereby provided for a purposeful supply of cleaned air to the motor unit 16a and / or the electronic unit 18a. The deflection channel 24a and the feed channel 44a each have a channel housing 98a, 100a which extends along a longitudinal extension 102a, 104a in the circumferential direction 106a, 108a around the deflection channel 24a and the feed channel 44a, so that a diffused escape of particles of the cooling air flow 20a is advantageously prevented from the deflection channel 24a and the feed channel 44a.

The deflection channel 24a has a spiral deflection channel section 30a, which opens into the feed channel 44a along the flow direction 52a. The spiral deflection channel section 30a is at least partially formed by an Archimedean spiral and in this case has a substantially constant cross-sectional area along the flow direction 52a. In the operation of the ventilation unit 14a, the cooling air flow 20a is also moved in a radial direction 110a of the deflection unit 22a from outside to inside along the deflection channel 24a and opens into the feed channel 44a at a center 112a via a main outlet opening 114a. Along the longitudinal extension 102a of the deflection channel 24a, the cooling air flow 20a at differing positions in each case has a differing direction of movement 38a, 40a. By means of the helical formation of Umlenkkanalabschnitts 30a acts on the particles of the cooling air flow 20a, a centrifugal force in the curved or curved deflection channel 24a in the radial direction 110a of the deflection unit 22a to the outside. This centrifugal force is dependent on a mass of the particles of the cooling air flow 20a, so that the heavy dust and / or dirt particles 26a are deflected to a greater extent in the radial direction 110a than the air 28a. Those on the heavy dust and / or dirt particles 26a acting centrifugal force is also greater than a suction force generated by the fan 88a in the deflection channel 24a, so that the heavy dust and / or dirt particles 26a within the Umlenkkanals 24a and the spiral Umlenkkanalabschnitts 30a in the radial direction 110a are deflected outwards and move in an outer region 116a through the spiral Umlenkkanalabschnitt 30a along the flow direction 52a. The air 28 a of the cooling air flow 20 a, however, is deflected by the suction force of the fan 88 a stronger than the heavy dust and / or dirt particles 26 a during operation of the ventilation unit 14 a and thus moves in a radially inner portion 118 a through the deflection channel 24 a and the spiral Umlenkkanalabschnitt 30a, so that due to the centrifugal force is a mass-dependent separation of particles and / or particles of the cooling air flow 20a within the spiral Umlenkkanalabschnitts 30a.

The deflection unit 22a also has two outlet openings 58a, 60a in a deflection region 56a or the spiral deflection channel section 30a, which are provided for escape of the dust and / or dirt particles 26a. The two outlet openings 58a, 60a are arranged on an outer wall 62a of the deflection channel 24a or of the spiral deflection channel section 30a in the radial direction 110a of the deflection unit 22a. The outlet openings 58a, 60a are arranged in a circumferential direction 120a of the deflection unit 22a offset by approximately 90 ° to each other. In addition, the ventilation unit 14a has two outlet channels 64a, 66a, which branch off from the deflection channel 24a at the outlet openings 58a, 60a. The outlet channels 64a, 66a also form along their longitudinal extent or along a flow direction in the outlet channels 64a, 66a a closed channel, which opens on the machine housing 12a of the power tool 10a via an opening 122a of the machine housing 12a to the outside. The two outlet channels 64a, 66a extend in a tangential direction 124a of the deflection channel 24a away from the deflection channel 24a, so that an effective outflow is achieved by utilizing a mass inertia of the dust and / or dirt particles 26a during operation of the electric tool 10a. During operation of the ventilation unit 14a, a partial air flow of the cooling air flow 20a with a high dust and / or dirt particle density flows through the outlet openings 58a, 60a and the outlet channels 64a, 66a, and a partial air flow of the cooling air flow 20a with a slight dust and / or dirt particle density through the main outlet opening 114a , In addition, the outlet channels 64a, 66a are provided with a valve 188a, which has a passage direction for blowing out the dust and / or dirt particles 26a due to a flow direction of the partial air flow with the dust and / or dirt particles 26a and an undesired suction of a cooling air flow 20a the outlet channels 64a, 66a advantageously prevented.

In the FIGS. 3 to 10 Alternative embodiments are shown. Substantially identical components, features and functions are basically numbered by the same reference numerals. To distinguish the embodiments, however, the letters a to f are added to the reference numerals of the embodiments. The following description is essentially limited to the differences from the embodiment in the FIGS. 1 and 2 , wherein with respect to the same components, features and functions on the description of the embodiment in the FIGS. 1 and 2 can be referenced.

In FIG. 3 is a power tool 10b shown with a to the FIG. 2 Alternative embodiment of a ventilation unit 14b, which is provided for cooling a motor unit 16b and / or an electronic unit 18b by sucking a cooling air flow 20b. The ventilation unit 14b has a dirt separator unit 90b formed by a U-shaped centrifugal separator 94b, which comprises a deflection unit 22b ( Figures 3 and 4 ). The deflecting unit 22b has an intake passage 50b, a deflecting passage 24b and a supply passage 44b, wherein the deflecting passage 24b is arranged along a flow direction 52b, 54b between the intake passage 50b and the deflecting passage 24b. The flow direction 52b of the cooling air flow 20b in the intake passage 50b is substantially opposite to the flow direction 54b of the cooling air flow 20b in the supply passage 44b. The deflection unit 22b is arranged along a main extension direction 84b of the power tool 10b in an end region 126b of a motor housing 82b facing away from a gear housing 80b. The deflection channel 24b has a bent deflecting channel section 30, which is embodied in a U-shaped or ring-segment-like manner and is arranged in the end region 126b. The deflection unit 22b has an additional housing shell 128b, which is arranged around the end region 126b of the motor housing 82b in a circumferential direction 130b, wherein the suction channel 50b between the additional housing shell 128b and a in the radial direction 132b of the motor housing 82b outwardly facing surface 134b of the motor housing 82b is arranged. The intake passage 50b extends in the main extension direction 84b of the power tool 10b. Between a radially inward-facing surface 136b of the motor housing 82b and a guide rib 138b of the dirt separator unit 90b, there is disposed the supply passage 44b having a cooling air flow 20b cleaned of dust and / or dirt particles 26b along a main extension direction 84b of the power tool 10b from the end region 126b leads in the direction of the motor unit 16b (Figures 3 and 4).

Furthermore, the deflection unit 22b has an outlet opening 58b, which is provided for the escape of a partial air flow of the cooling air flow 20b with a high density of heavy dust and / or dirt particles 26b during operation of the ventilation unit 14b. The outlet opening 58b is arranged on an outer wall 62b in a radial direction 140b of the curved deflection channel section 30b, wherein an outlet channel 64b of the ventilation unit 14b branches off at the outlet opening 58b. In this case, the outlet channel 64b is formed between the additional housing shell 128b and the motor housing 82b, which form a substantially inwardly directed outlet channel 64b in the radial direction 132b of the electric tool 10b (FIG. Figures 3 and 4 ). A principle of a separation of heavy dust and / or dirt particles 26b of air of the cooling air flow 20b is analogous to the embodiment in the FIGS. 1 and 2 , In a further embodiment of the invention, it is also conceivable that the outlet channel 64b is provided with a valve which has a passage direction for blowing out the dust and / or dirt particles 26b along a flow direction of a partial air flow with the dust and / or dirt particles 26b and advantageously prevents unwanted suction of a cooling air flow 20b through the outlet channel 64b. In addition, it is also conceivable that, in order to increase a cleaning effect of the dirt separator unit 90b, the deflection unit 22b has a plurality of curved or curved deflection channel sections 30b arranged one after the other.

In FIG. 5 an alternative embodiment of a ventilation unit 14c is shown for a power tool. The ventilation unit 14c comprises a dirt separator unit 90c with a deflection unit 22c and an outlet channel 64c. The deflection unit 22c has a deflection channel 24c with a plurality of bent deflection channel sections 30c. In addition, the deflecting unit 22c has an intake passage 50c and a supply passage 44c, and a flow direction 52c of a cooling air flow 20c in the intake passage 50c is substantially opposite to a flow direction 54c of the cooling air flow 20c in the supply passage 44c. The deflection channel 24c has a plurality of main outlet openings 114c, through which an almost dirt-free partial air flow of the cooling air flow 20c can escape into the feed channel 44c. The main outlet openings 114c are arranged between webs 142c of a machine housing 12c, wherein the flow direction 52c of the cooling air flow 20c in the supply channel 44c is aligned substantially parallel to a longitudinal extension of the webs 142c. The exhaust passage 64c is disposed along a direction 144c extending across the longitudinal extensions of the lands 142c in a central region 146c of the dirt separator unit 90c, and is surrounded on both sides by the supply passage 44c along this direction 144c. The feed channel 44c is also interposed along the direction 144c the intake passage 50c and the exhaust passage 64c. A deflection of the cooling air flow 20c in the deflection unit 22c takes place analogously to the exemplary embodiments in FIGS FIGS. 1 to 4 ,

In FIG. 6 an alternative embodiment of a power tool 10d is shown with a ventilation unit 14d. The ventilation unit 14d has a dirt separator unit 90d formed by a centrifugal separator 94d, which is designed as a cyclone separator. The dirt separator unit 90d is arranged on an end region 126d facing a motor unit 16d along a main direction of extent 84d of the electric tool 10d. The dirt separator unit 90d has a separate housing 148d which extends along the main extension direction 84d of the electric tool 10d from a motor housing 82d of the electric tool 10d. In a partial area 150d of the housing 148d facing the motor housing 82d, it is cylindrical in shape along the main extension direction 84d, wherein suction openings 86d are arranged between the housing 148d and the motor housing 82d. A partial region 152d of the housing 148d facing away from the motor housing 82d is conically tapered along the main extension direction 84d of the motor unit 16d in a direction of the dirt separator unit 90d and opens into a cylindrical outlet channel 64d along the main extension direction 84d. The motor housing 82d has a tapered extension 154d which extends into the portion 150d of the housing 148d facing the motor housing 82d, a cross-sectional area of the extension 154d being smaller than a cross-sectional area of the portion 150d of the housing 148d. The extension 154d is designed as a feed channel 44d, by means of which a partial air flow of the cooling air flow 20d cleaned of dust and / or dirt particles is guided to the motor unit 16d or an electronic unit in operation. In principle, it is also conceivable that the dirt separator unit 90d is arranged within the motor housing 82d or is integrated in this.

During operation of the power tool 10d, the cooling air flow 20d is sucked in by means of a fan wheel (not shown). In this case, an air is sucked in through the suction openings 86d, wherein a shape of the suction openings 86d is configured such that the air is accelerated at least partially in a tangential direction or in a circumferential direction 48d of the feed channel 44d. The circumferential direction 48d extends perpendicular to the main extension direction 84d around the feed channel 44d. In addition, the dirt separator unit 90d has a deflection unit 22d with a deflection channel 24d, which extends between a surface 158d of the feed channel 44d facing outward in the radial direction 156d of the feed channel 44d and the housing 148d. The feed channel 44d is formed here as a dip tube 46d and extends into a deflection region 56d of the deflection unit 22d, wherein the deflection channel 24d is arranged in the radial direction 156d around the dip tube 46d. The sucked air is also moved by the motor unit 16d in the direction of the dirt separator unit 90d due to a suction force of the ventilation unit 14d, so that the sucked cooling air flow 20d helically rotates around the dip tube 46d in the circumferential direction 48d. Due to the conically tapered portion 152d of the housing 148d, the sucked cooling air flow 20d rotates in helical orbits with a radius decreasing along the motor housing 82d toward the dirt separator unit 90d so that an increasing external centrifugal force acting on the cooling air flow 20d becomes mass-dependent Separation of dust and / or dirt particles and air of the cooling air flow 20d within the deflection unit 22d leads. In this case, the heavy dust and / or dirt particles are deflected outwards in the radial direction 156d and deposited on a conically tapered housing wall 162d, while the air is deflected due to a suction force of the ventilation unit 14d into an inner region 160d in the radial direction 156d. At an end of the conically tapered portion 152d facing away from the motor unit 16d, the air of the cooling air flow 20d is deflected by a suction force generated by the fan wheel in the direction of the motor unit 16d along a flow direction 52d. The heavy dust and / or dirt particles are entrained together with a partial air flow 164d from the housing wall 162d in the direction of the outlet channel 64d and discharged through it. A cleaning action of the dirt separator unit 90d may depend on a suction power of the fan unit and / or a geometry of the tapered partial region 152d of the housing 148d and / or an alignment of the suction openings 86d and / or further components that appear appropriate to the person skilled in the art. In a further embodiment of the invention, it is also conceivable that the outlet channel 64a is provided with a valve which has a passage direction for blowing out the dust and / or dirt particles along a flow direction of the partial air flow with the dust and / or dirt particles, and prevents unwanted suction of a cooling air flow 20d through the outlet channel 64a advantageous.

In FIG. 7 an alternative dirt separator unit 90e of a power tool is shown. The dirt separator unit 90e is formed by a gravity separator unit and has a deflection unit 22e with a deflection channel 24e, which is provided for a deflection of a cooling air flow 20e to a separation of dust and / or dirt particles 26e and air 28e of the cooling air flow 20e. The deflection channel 24e has a multiplicity of deflection channel sections 34e, 36e, wherein the deflection channel sections 34e, 36e are each arranged parallel to one another are. A direction of movement 38e of the cooling air flow 20e is in this case directed in the deflection channel section 34e in a direction of movement 40e of the cooling air flow 20e from directly adjacent deflection channel sections 36e. For this purpose, the dirt separator unit 90e has two housing shells 166e, which are each designed comb-like in the region of the deflection unit 22e, with comb tooth-like extensions 168e projecting into the deflection channel 24e substantially perpendicular to the housing shell 166e. The comb-tooth-like extensions 168e of the two housing shells 166e are offset along an axial direction 170e of the deflection channel 24e, so that a deflection channel section 34e, 36e is arranged between each two comb-tooth-like extensions 168e. In each case one end 172e of a comb-like extension 168e, which faces away from the housing shell 166e, on which the comb-like extension 168e is arranged, the cooling air flow 20e is thereby deflected. The deflecting unit 22e is integrated in the electrical appliance in such a way that the direction of movement 38e of the cooling air flow 20e in the deflecting duct section 34e is oriented essentially perpendicular to a gravitational force or a gravitational force, as may be advantageous in stationary electrical appliances in particular. For heavy particles of the cooling air flow 20e, the gravitational force of the particles thus counteracts a suction force of the ventilation unit 14e, so that they deposit in the direction of gravity. In addition, acts on the heavy particles of the cooling air flow 20e during the deflection, a high centrifugal force, which deflects the particles to the outside, so that they bounce on the comb-tooth-like extensions 168e and are stopped. For receiving or accumulating deposited dust and / or dirt particles 26e, the deflection unit 22e has a plurality of chambers 42e, which are arranged in a deflection region 56e in the deflection channel 24e. In addition, the chambers 42e are provided with a resealable opening flap 186e, by means of which a cleaning of the chambers 42e is made possible for an operator of the electrical appliance. In this case, the opening flap 186e can be opened and closed by means of a closure element (not shown in more detail) on the opening flap 186e and is pivotably arranged on the housing shell 166e. However, it is also conceivable that the opening flap 186e is activated via a switch-on element of the power tool and thus can be opened or closed. In addition, the opening flap 186e may remain closed in the operation of the ventilation unit due to a negative pressure in the deflection channel 24e and only in a non-operation due to a spring force of a preloaded spring in an open state.

In the FIGS. 8 to 10 a filter device 68f for a power tool is shown. The filter device 68f has a filter unit 70f and a dedusting unit 74f. The filter unit 70f comprises a filter element 72f and a frame element 174f which is provided for receiving the filter element 72f and by means of which the filter element 72f can be attached to the power tool. The dedusting unit 74f is provided for dedusting the filter element 72f and has a dedusting element 76f for this purpose. The dedusting element 76f is movably mounted on the frame element 174f along a longitudinal extent 176f of the dedusting element 76f, the frame element 174f having a guide element 178f for this purpose. At an end remote from the filter element 72f along the longitudinal extent 176f of the dedusting element 76f, the latter has an actuating element 180f, by means of which an operator can move the dedusting element 76f along its longitudinal extent 176f. At an end facing away from the actuating element 180f along the longitudinal extent 176f of the dedusting element 76f, the latter has a stop element 182f which abuts the filter element 72f at this end. Along the longitudinal extent 176f of the dedusting element 76f, between the stop element 182f and the frame element 174f of the filter unit 70f, there is arranged a spring element 78f, which is formed by a helical spring and which is arranged in a circumferential direction 184f around the dedusting element 76f. In a relaxed operating position of the spring element 78f, the stop element 182f bears against the filter element 72f. For dedusting the filter element 72f, the actuating element 180f is moved together with the dedusting element 76f against the spring force of the spring element 78f along the longitudinal extension 176f from the stop element 182f in the direction of the actuating element 180f. After releasing the operating member 180f, the dedusting member 76f is accelerated toward the filter member 72f along the longitudinal extension 176f due to the spring force of the spring member 78f, and strikes the filter member 72f in an end position. As a result, a dust adhering to the filter element 72f is released and falls off the filter element 72f.

Claims (14)

1. Electric tool having a machine housing (12a-e) and a ventilation unit (14a-e) which is provided to cool a motor unit (16a-e) and/or electronic unit (18a-e) enclosed by the machine housing (12a-e) by drawing in a cooling air stream (20a-e), and which has a deflection unit (22a-e), characterized in that, in order to provide virtually dust-free and/or dirt-free cooling air for cooling the motor unit (16a-e) and/or the electronic unit (18a-e), the deflection unit (22a-e) has at least one deflection duct (24a-e) which is provided to separate dirt particles (26a-e) and air (28a-e) of the cooling air stream (20a-e) by means of deflection of the cooling air stream (20a-e).
2. Electric tool according to Claim 1, characterized in that the deflection duct (24a-d) has at least one curved deflection duct portion (30a-d).
3. Electric tool according to either of the preceding claims, characterized in that the deflection duct (24a) has at least one spiral-shaped deflection duct portion (30a).
4. Electric tool according to one of the preceding claims, characterized in that the deflection duct (24e) has a multiplicity of deflection duct portions (34e, 36e), wherein, in at least one deflection duct portion (34e), the cooling air stream (20e) exhibits a direction of movement (38e) which is substantially in the opposite direction to a direction of movement (40e) of adjacent deflection duct portions (36e).
5. Electric tool according to one of the preceding claims, characterized in that at least one of the deflection duct portions (34e, 36e) has a chamber (42e) which is provided for deposition of the dirt particles (26e).
6. Electric tool according to one of the preceding claims, characterized in that the deflection unit (22d) has at least one feed duct (44d) which is in the form of a dip tube (46d).
7. Electric tool according to Claim 6, characterized in that the deflection duct (24d) is arranged at least partially around the dip tube (46d) in a circumferential direction (48d) of the dip tube (46d).
8. Electric tool according to one of the preceding claims, characterized in that the deflection unit (22b; 22c) has at least one intake duct (50b; 50c) and at least one feed duct (44b; 44c), and a direction of flow (52b; 52c) of the cooling air stream (20b; 20c) in the intake duct (50b; 50c) is substantially in the opposite direction to a direction of flow (54b; 54c) of the cooling air stream (20b; 20c) in the feed duct (44b; 44c).
9. Electric tool according to one of the preceding claims, characterized in that the deflection unit (22a-d) has, in at least one deflection region (56a-d), at least one outlet opening (58a-d, 60a) which is provided for escape of the dirt particles (26a-d) from the cooling air stream (20a-d).
10. Electric tool according to Claim 9, characterized in that the outlet opening (58a, 60a; 58b) is arranged at an outer wall (62a; 62b) of a curved deflection duct portion (30a; 30b) of the deflection duct (24a; 24b).
11. Electric tool at least according to Claim 9, characterized in that the ventilation unit (14a-d) has at least one outlet duct (64a-d, 66a) which branches off from the deflection duct (24a-d) at the outlet opening (58a-d, 60a).
12. Electric tool filter device having at least one filter unit (70f) which has at least one filter element (72f), characterized in that the filter unit (70f) has a dust removal unit (74f) which is provided to remove dust from the filter element (72f).
13. Electric tool filter device according to Claim 12, characterized in that the dust removal unit (74f) has at least one dust removal element (76f) which bears against the filter element (72f) in at least one operating position.
14. Electric tool filter device at least according to Claim 12, characterized in that the dust removal unit (74f) has at least one spring element (78f) which is provided for a dust removal movement of the dust removal element (76f).

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