EP4331775A1 - Machine tool with a sealing device - Google Patents

Abstract

Machine tool (1), in particular a hammer drill or chisel hammer, with a housing (5) having a handle area (7, 27) and an assembly (9) comprising a striking mechanism (11) and a drive device (13), the assembly (9) being in the Is arranged essentially within the housing (5) and is arranged movably relative to the housing (5). A center of gravity (15) of the assembly (9) is arranged at a distance from an impact axis (19). A isolation device (87) restricts an air flow between the assembly (9) and the housing (5), the isolation device (87) being connected to the assembly (9) and the housing (5) and the assembly (9) with respect to a vertical direction (Y) of the machine tool (1).

Description

Machine tool with a partitioning device

The present invention relates to a machine tool, in particular a drill and/or chisel hammer, according to the type defined in more detail in the preamble of patent claim 1.

Machine tools, in particular drill and/or chisel hammers, are known from practice, in which a housing having a striking mechanism and a drive device is vibration-decoupled from electronics and a battery interface device. To prevent dust from entering the area containing the electronics, a uniaxially acting air barrier, for example in the form of a rubber sleeve, with a line of action in the longitudinal direction of the machine tool is known.

From the DE 10 2020 216 538 A1 a drill and/or chisel hammer is known which has an outer housing and an inner housing. The inner housing is arranged in the outer housing, the inner housing having a drive unit and an impact unit. A vibration damping unit with a vibration damping element for damping vibrations occurring during operation is provided, by means of which a main handle connected to the outer housing is decoupled from the inner housing. The inner housing is rotatably mounted relative to the outer housing about an axis of rotation arranged in the area of an instantaneous pole of the impact mechanism unit.

In such an embodiment, the provision of such a uniaxial air bulkhead is disadvantageous because it only compensates for vibrations in the longitudinal direction and is also arranged in a lower region of the machine tool in a space-unfavorable manner.

It is the object of the present invention to provide a machine tool, in particular a hammer drill or chisel hammer, in a machine tool with an assembly that is movably mounted relative to a housing to achieve a space-saving seal between the assembly and the housing when the assembly moves relative to the housing in different spatial directions .

The object is solved by the subject matter of independent claim 1. Further advantageous embodiments of the invention can be found in the corresponding subclaims.

A machine tool, in particular a hammer drill or chisel hammer, is provided with a housing having a grip area and an assembly comprising a striking mechanism and a drive device, the assembly being arranged essentially within the housing and being arranged to be movable relative to the housing, with a center of gravity of the Assembly is arranged at a distance from an impact axis.

According to the invention, it is proposed that a partitioning device is provided in order to restrict and in particular essentially completely prevent an air flow between the assembly and the housing, wherein the partitioning device is connected to the assembly and to the housing and surrounds the assembly with respect to a vertical direction of the machine tool .

With a machine tool designed according to the invention, the proposed positioning and design of the isolation device achieves a space-saving seal between the assembly and the housing when the assembly moves relative to the housing with large deflections in the longitudinal direction and in particular smaller deflections in the vertical and/or transverse direction of the machine tool .

Due to the inventive arrangement of the isolation device circumferential to the vertical direction, the isolation device can, in addition to compensating for movements of the assembly relative to the housing in the longitudinal direction, advantageously cope with large movements of the assembly relative to the housing also in a vertical direction and/or a transverse direction and thereby securely between the assembly and seal the housing.

A machine tool designed according to the invention has the advantage that air circulation in the area of an intake and exhaust area of the drive device and also electrical connections of the drive device and the electrical system are not negatively influenced by the isolation device and a maximum cross section for cooling air is available for the drive device.

In addition, the arrangement of the isolation device according to the invention makes it possible to easily achieve favorable cooling of a stator by means of cooling that can be adjusted essentially symmetrically to a vertical axis.

Due to the arrangement of the isolation device all around with respect to the vertical direction of the machine tool, a lower region of the machine tool in the vertical direction is free from the isolation device, so that, for example, electrical connections and/or a cable harness and/or a dust extraction system can be arranged in this area in a simple manner.

A simple coupling of the isolation device with the housing and the assembly is achieved if the isolation device is connected to the housing with a first area and is attached to the assembly with a second area.

In an advantageous embodiment of the invention, the partitioning device has a flexible element and a dimensionally stable element. The flexible element allows a desired sealing effect to be achieved, whereas the dimensionally stable element allows the sealing device to be connected to the housing with the corresponding geometry in a simple manner.

In an advantageous embodiment of the invention, the flexible element has at least two regions which run essentially in the vertical direction and which are connected to one another in the longitudinal direction. By designing the partitioning device in this way, large movements of the assembly relative to the housing in the longitudinal direction are achieved while at the same time being able to move in the transverse and vertical directions.

Preferably, the partitioning device has an area with a U-shaped cross section. Depending on the dimensioning of the dimensions, the possibility of movement of the assembly relative to the housing can be easily adjusted and adapted to the available installation space. The U-shaped area can be designed to be open both in the vertical direction upwards and in the vertical direction downwards.

A favorable connection of the isolation device to the assembly and/or the housing is achieved if the isolation device is connected to the assembly and/or the housing via a form fit and/or material fit.

In an advantageous embodiment of a machine tool according to the invention, the isolation device engages with the first region and/or second region, particularly in the longitudinal direction of the machine tool, in a recess or groove in the housing or the assembly.

Alternatively or additionally, it can be provided that the sealing device encompasses an element of the housing or the assembly with the first region and/or the second region.

In an advantageous embodiment of the invention it is provided that the flexible element surrounds the dimensionally stable element in the circumferential direction of the vertical direction. This creates a simple connection between the elements, which reliably prevents the passage of air in this area.

In an advantageous embodiment of a machine tool according to the invention, the flexible element is designed with an elastomer. The flexible element preferably represents a membrane, in particular with an elastomeric material.

In an advantageous embodiment of the invention, the dimensionally stable element is made of plastic. In this way, the desired stability can be achieved in a simple manner. In principle, other materials, such as metallic materials, can also be used.

In an advantageous embodiment of a machine tool according to the invention, the isolation device is designed such that it allows a movement of the assembly relative to the housing in the longitudinal direction of greater than 0.8 mm, in particular greater than 1.0 mm.

In an advantageous embodiment of a machine tool according to the invention, the isolation device is in a neutral or unbiased position when the assembly is in an approximately central position with respect to the housing in relation to the longitudinal direction between two end positions. In this way, both movements of the assembly relative to the housing in the direction of the maximum deflection position and in the direction of the minimum deflection position can be easily compensated for and the isolation device seals securely between the assembly and the housing in all operating states.

Further advantages result from the following description of the figures. Various exemplary embodiments of the present invention are shown in the figures. The figures, the description and the claims contain numerous features in combination. The person skilled in the art will also expediently consider the features individually and combine them into further sensible combinations.

Fig. 1

eine vereinfachte seitliche Schnittansicht einer als Bohrhammer ausgeführten Werkzeugmaschine mit einem äußeren Gehäuse und einer in dem Gehäuse angeordneten Baugruppe, umfassend eine Schlagwerkeinrichtung und eine Antriebseinrichtung, wobei die Baugruppe gegenüber dem Gehäuse mittels einer vorderen Entkopplungsvorrichtung und einer hinteren Entkopplungsvorrichtung verlagerbar ist, wobei zur Abdichtung zwischen der Baugruppe und dem Gehäuse eine Abschotteinrichtung vorgesehen ist, und wobei die Baugruppe in einer gegenüber dem Gehäuse vorderen Endposition ohne äußere Krafteinwirkung gezeigt ist;

Fig. 2

eine Fig. 1 entsprechende Darstellung der Werkzeugmaschine, wobei die Baugruppe in einer an einem Anschlag anliegenden hinteren Endposition bei einem Einwirken einer äußeren Kraft gezeigt ist;

Fig. 3

eine Fig. 1 und Fig. 2 entsprechende Schnittansicht der Werkzeugmaschine, wobei die Baugruppe in einer im Wesentlichen mittig zwischen der vorderen Endposition und der hinteren Endposition befindlichen mittigen Position gezeigt ist;

Fig. 4

eine Fig. 1 bis Fig. 3 entsprechende Schnittansicht der Werkzeugmaschine, wobei die Baugruppe bei einem Einwirken einer äußeren Kraft gegenüber dem Gehäuse um eine Querachse verdreht ist;

Fig. 5

eine Schnittansicht der Werkzeugmaschine gemäß Fig. 1;

Fig. 6

ein Ausschnitt der Werkzeugmaschine gemäß Fig. 5, wobei die Abschotteinrichtung näher ersichtlich ist;

Fig. 7

eine dreidimensionale Ansicht eines Ausschnitts der Werkzeugmaschine ohne das Gehäuse, wobei die Abschotteinrichtung näher ersichtlich ist;

Fig. 8

eine dreidimensionale Ansicht eines Ausschnitts der Werkzeugmaschine, wobei ein Ausblasbereich und die Abschotteinrichtung näher ersichtlich sind;

Fig. 9

eine Schnittansicht eines im Wesentlichen Fig. 7 entsprechenden Ausschnitts der Werkzeugmaschine;

Fig. 10

eine Seitenansicht der Abschotteinrichtung in Alleinstellung;

Fig. 11

eine Draufsicht auf die Abschotteinrichtung gemäß Fig. 10 in Alleinstellung;

Fig. 12

eine Schnittansicht der Abschotteinrichtung gemäß Fig. 10 und Fig. 11;

Fig. 13

eine Schnittansicht der Abschotteinrichtung gemäß Fig. 10 bis Fig. 12, wobei die Abschotteinrichtung in einer Position bei sich in einer Endposition gegenüber dem Gehäuse befindlichen Baugruppe; und

Fig. 14

eine weitere Schnittansicht der Abschotteinrichtung gemäß Fig. 10 bis Fig. 13, wobei die Abschotteinrichtung in einer Position bei sich in einer Endposition gegenüber dem Gehäuse befindlichen Baugruppe.

Show it:

Fig. 1

a simplified side sectional view of a machine tool designed as a hammer drill with an outer housing and an assembly arranged in the housing, comprising a striking mechanism and a drive device, the assembly being displaceable relative to the housing by means of a front decoupling device and a rear decoupling device, for sealing between the A partitioning device is provided for the assembly and the housing, and the assembly is shown in a front end position relative to the housing without external force;

Fig. 2

one Fig. 1 corresponding representation of the machine tool, the assembly being shown in a rear end position resting against a stop when an external force is applied;

Fig. 3

one Fig. 1 and Fig. 2 corresponding sectional view of the machine tool, the assembly being shown in a central position substantially midway between the front end position and the rear end position;

Fig. 4

one Fig. 1 to Fig. 3 corresponding sectional view of the machine tool, wherein the assembly is rotated about a transverse axis relative to the housing when an external force is applied;

Fig. 5

a sectional view of the machine tool according to Fig. 1 ;

Fig. 6

a section of the machine tool according to Fig. 5 , whereby the isolation device can be seen in more detail;

Fig. 7

a three-dimensional view of a section of the machine tool without the housing, with the isolation device being shown in more detail;

Fig. 8

a three-dimensional view of a section of the machine tool, with a blow-out area and the isolation device being shown in more detail;

Fig. 9

a sectional view of a substantially Fig. 7 corresponding section of the machine tool;

Fig. 10

a side view of the isolation device alone;

Fig. 11

a top view of the isolation device according to Fig. 10 in isolation;

Fig. 12

a sectional view of the isolation device according to Fig. 10 and Fig. 11 ;

Fig. 13

a sectional view of the isolation device according to Fig. 10 to Fig. 12 , wherein the isolation device is in a position when the assembly is in an end position relative to the housing; and

Fig. 14

a further sectional view of the partitioning device according to Fig. 10 to Fig. 13 , wherein the isolation device is in a position with the assembly located in an end position relative to the housing.

Examples:

Fig. 1 to Fig. 4 show a machine tool 1, which is designed here as a hammer drill or combination hammer, but in an alternative embodiment can also be designed as a chisel hammer or the like.

In the present case, the machine tool 1 is designed as a wireless machine tool with an accumulator 3; in an alternative embodiment, it can be provided for mains operation.

The machine tool 1 is designed here in an angular design and has a housing 5 which has a rear handle area 7 in a D-shape. The housing 5, which can be made in one or more parts, is here firmly connected to the handle area 7 that can be grasped by a user. In the present case, the housing 5 is divided in the longitudinal direction Z and designed in a so-called pot design. Alternatively, the housing 5 can also have two housing halves that can be connected to one another in the transverse direction X and can be designed in a so-called shell design.

Arranged within the housing 5 is a structural unit or assembly 9, which has a conventionally designed percussion mechanism 11 and a drive device 13 designed as an electric motor, which is designed to drive the percussion mechanism 11. In this case, the assembly 9 is L-shaped.

In the present case, a drilling or chiseling operation is possible by means of the assembly 9, with the tool 17 moving back and forth in an oscillating manner in a striking axis direction in the chiseling operation. In the drilling or hammer drilling operation, the tool also performs a rotating movement around the impact axis.

Electronics 18 can also be seen, which is connected to the drive device 13 in a known manner via lines 20.

The machine tool 1 has, in a conventionally known manner, a tool holder 16, via which a tool 17, for example a chisel or the like, can be detachably and operatively connected to the structural unit 9.

The figures also show a longitudinal direction designated Z or Z direction, a vertical direction designated Y or Y direction and a transverse direction designated X or X direction. X, Y and Z are axes of a Cartesian coordinate system and are each perpendicular to one another. Without the action of an external force, the longitudinal direction Z is congruent with the impact axis, which is defined by a central axis of the tool or the tool holder 16.

In the embodiment shown, 15 shows a center of gravity of the structural unit 9, which is arranged below the longitudinal direction Z with respect to the vertical direction Y in the illustrations shown and is therefore spaced from the longitudinal direction Z.

The structural unit 9 can have a separate inner housing 21, which in particular includes the impact mechanism 11 and the drive device 13 or within which the impact mechanism 11 and the drive mechanism 13 are in particular almost completely arranged.

For example in Fig. 1 a front decoupling device 23 and a rear decoupling device 25 are shown, which can basically be designed with one decoupling device or several decoupling devices. In the embodiment shown, the front decoupling device 23 is arranged in the longitudinal direction Z in front of the rear decoupling device 25, ie closer to the tool holder 16 and in an area facing away from the rear handle area 7.

In Fig. 1 to Fig. 4 A front handle area 27 or side handle can be seen, which in the present case can be detachably brought into operative connection with the housing 5 in the area of the front decoupling device 23, for example by means of a tension band. In the present case, the front handle area 27 extends essentially in the transverse direction

The structural unit 9 is mounted relative to the housing 5 both via the front decoupling device 23 and the rear decoupling device 25, the structural unit 9 relative to the housing 5 both in the area of the front decoupling device 23 and in the area of the rear decoupling device 25 both in the longitudinal direction Z , can be moved in the transverse direction X as well as in the vertical direction Y. The displacement possibility s in the longitudinal direction Z is, for example, a maximum of approximately 10 mm, but can also be up to 20 mm or larger in other designs. The possibility of displacement in the transverse direction

In order to define a maximum movement path in the transverse direction The number and position of the stops 37 can basically be freely selected, preferably at least one, in particular two, stops 37 being provided on both sides of the structural unit 9 for each direction X, Y and Z. When the machine tool is drilling or chiseling, the interaction between a surface to be machined and the tool 17 creates vibrations or accelerations that mainly act in the direction of the impact axis. Due to the angular design of the machine tool 1, in which the center of mass 15 of the structural unit 9 is not on the impact axis or longitudinal axis Z, this also results in vibrations or accelerations transverse to the impact axis in the vertical direction Y. For example, due to unbalance forces in the area of the drive device 13 During operation of the machine tool 1 there are also vibrations or accelerations in the transverse direction X.

During operation of the machine tool 1, vibrations and accelerations occur in the area of the structural unit 9. These can be transferred via the front decoupling device 23 and the rear decoupling device 25 to the housing 5 having the front handle area 27 and the rear handle area 7. The aim is to use the decoupling devices 23, 25 to reduce or dampen as much as possible the vibrations or accelerations that arise during operation of the machine tool 1 in the area of the structural unit 9.

Assembly 9 is in Fig. 1 shown in the rest position in which the machine tool 1 is not operated or in which the assembly 9 is in the front end position in contact with the front stop 37a. In Fig. 2 the assembly 9 is shown in the rear end position and with the maximum deflection in the longitudinal direction Z, in which the assembly 9 is at the stops 37b.

In the exemplary embodiment according to Fig. 1 to Fig. 4 a lateral stop 37d is shown which is assigned to a left side in the transverse direction The side stops 37d limit a movement path of the assembly 9 relative to the housing 5 in the transverse direction X.

In addition, in the present case an upper stop 37f and a lower stop 37g are provided, which limit a movement path of the assembly 9 relative to the housing 5 in the vertical direction Y.

The rear decoupling device 25 will first be described in more detail below.

In the present case, the rear decoupling device 25 has a first decoupling device 31 and two second decoupling devices 33, 35.

The second decoupling devices 33, 35 of the rear decoupling device 25 have spring properties and/or damping properties in the longitudinal direction Z and are designed here as spring devices with an axis of action essentially in the longitudinal direction Z. The spring devices 33, 35, designed here as a cylindrical coil spring, press the assembly 9 relative to the housing 5 Fig. 1 into the front end position in which the assembly 9 rests against the front stop 37a. In Fig. 2 the spring devices 33, 35 are shown in a maximally tensioned position. The spring devices 33, 35 assume these when the assembly 9 is in the rear end position relative to the housing 5, in which the assembly 9 rests on the rear stops 37b, 37c. In Fig. 3 the assembly 9 is shown relative to the housing 5 in a middle position, in which a distance of the assembly 9 in the longitudinal direction Z from the front stop 37a and from the rear stops 37b, 37c is essentially identical and is approximately s/2.

The spring devices 33, 35 are arranged at a distance from one another in the vertical direction Y, with the spring device 33 in the present case being arranged in the area of the impact axis 19. In the present case, the spring device 35 is arranged in the area of the drive device 13 between the assembly 9 and the housing 5.

In alternative embodiments, further second spring devices can also be provided, for example two spring devices 35 arranged at a distance from one another in the transverse direction X can be provided. Alternatively or in addition to this, further spring devices arranged at a distance from one another in the vertical direction Y can also be provided.

When executed in accordance with Fig. 1 to Fig. 4 a single first decoupling device 31 can be provided, which is arranged at any position between the assembly 9 and the housing 5. It is particularly advantageous if a distance between a decoupling device 29 of the front decoupling device 23 and the first decoupling device 31 in the longitudinal direction Z is as large as possible.

In alternative embodiments, several first decoupling devices 31 can also be provided, which are arranged at a distance from one another, in particular in the vertical direction Y, between the assembly 9 and the housing 5.

In Fig. 4 It is shown in a greatly exaggerated manner that the assembly 9 can rotate relative to the housing 5 about an axis running in the transverse direction X during operation of the machine tool 1. The assembly 9 can also rotate relative to the housing 5 about an axis running in the vertical direction Y and/or about an axis running in the longitudinal direction Z. The front decoupling device 23 and the rear decoupling device 25 are designed in such a way that they enable such rotations and in particular can also dampen vibrations or accelerations transmitted thereby.

In Fig. 1 to Fig. 4 A further first decoupling device 36 is also shown, which is arranged in a lower region of the machine tool 1 in the vertical direction Y between the assembly 9 and the housing 5. The further first decoupling device 36 is optional and can improve spring and/or damping properties if necessary.

In Fig. 5 the rear decoupling device 25 has a single first decoupling device 31.

The first decoupling device 31 has a first sliding element 39, which is designed here as a pin-shaped element with a central axis 49. The pin-shaped element 39, which is designed, for example, as a steel pin, is here positively connected to the housing 5 by means of a screw connection via a thread 41 arranged in the longitudinal direction Z in the rear end region. The first decoupling device 31 also has a second sliding element 43 which interacts with the first sliding element 39 and serves as a sliding partner for this purpose, which in the present case is designed as a sliding bushing. The sliding bushing 43 interacts with a bearing block 47 fixed to the assembly via a decoupling element 45. In the present case, the bearing block 47 is connected to a gear housing of the assembly 9 via a positive connection.

The decoupling element 45 is fixed here in the direction of the central axis 49 relative to the sliding bushing 43. For this purpose, the sliding bushing 43, which is made in particular with plastic, is preferably clipped into the decoupling element 45. In a region outer in the radial direction to the central axis 49, the decoupling element is fixed in the direction of the central axis 49 via a bushing 51 and the bearing block 47.

It can also be provided that the decoupling element 45 is glued to the sliding bush 43 and/or to the bearing block 47.

The decoupling element 45 is here tubular with a substantially constant wall thickness. In an alternative embodiment, the decoupling element 45 can have a varying wall thickness on the circumference of the central axis 49.

In the present case, the decoupling element 45 is designed with an elastomer. In the rest position of the assembly 9, the decoupling element 45 has a preload in the radial direction of the central axis 49 in order to achieve a desired radial rigidity in the transverse direction X and vertical direction Y.

In the area of the first decoupling device 31, the assembly 9 can be rotated relative to the housing 5.

In addition to the in Fig. 6 In the embodiment shown with a first decoupling device 31, a further essentially identical first decoupling device can also be provided, in a lower region with respect to the vertical direction Y and in a rear region with respect to the longitudinal direction Z of the assembly 9. In particular, such a further first decoupling device can be arranged in the area of the drive device 13.

Furthermore, in Fig. 6 the decoupling device 29 of the front decoupling device 23 can be seen. The front decoupling device 29 has a first sliding element 75 fixed to the housing and a second sliding element 77 which interacts with the assembly 9. The second sliding element 77 is arranged in a groove 79 of the assembly and is essentially fixed in the longitudinal direction Z relative to the assembly. The second sliding element 77 is biased in the radial direction with respect to the longitudinal direction Z. For this purpose, a further groove 81 is provided in the radial direction within the groove 79, in which an O-ring 83 is arranged. The O-ring 83 applies a force acting outwards in the radial direction to the second sliding element 77.

The first sliding element 75 is designed here as a steel bushing and is positively connected to the housing 5. The steel bushing 75 is made so solid that it counteracts to the desired extent any deformation of the housing 9 in the area of the front handle area 27 by connecting it by means of a tension band and counteracts the non-uniform circumferential forces present.

In the present case, the second sliding element 77 is designed with a slotted tubular ring made of plastic. The second sliding element 77 is preferably designed as a so-called ^Slydring® . The selected material pairing of the first sliding element 75 and the second sliding element 77 achieves good sliding properties, which enables the sliding elements 75 and 77 to be displaced relative to one another during operation, particularly in the longitudinal direction Z. The interaction of the O-ring 83 and the second sliding element 77 enables the assembly 9 to be rotated relative to the housing 5 in this area.

In Fig. 5 A sealing device 87 is also shown, by means of which a negative pressure side of the machine tool 1 is sealed from a pressure side of the machine tool 1 between the assembly 9 and the housing 5. The only open cross section between the pressure side and the vacuum side is a fan 89, which is provided for building up pressure on the pressure side.

In Fig. 9 It can be seen that the sealing device 87 seals between an air intake area 93, which represents a negative pressure area, and an air exhaust area 95, which represents an overpressure area. This sealing is ensured in all operating states of the machine tool 1 and thus in the position of the assembly in the front end position or in the rear end position or in an intermediate position in between relative to the housing 9.

In addition, the isolation device 87 also seals securely between the housing 5 and the assembly 9 when the assembly 9 is rotated relative to the housing 5 about an axis running in the transverse direction X, vertical direction Y and/or longitudinal direction Z.

In the present case, the isolation device 87 can be brought into engagement with a drive housing 91 of the drive device 13 from a lower side in the vertical direction Y, so that the isolation device 87 is connected to the drive housing 91 on a radially inner side in the assembled state. A lower region of the drive device 13 in the vertical direction Y is thus free for the arrangement of, for example, cable harnesses which are connected to an outside of the drive housing 91.

In the Fig. 10 to Fig. 12 Isolation device 87 shown alone or the air barrier in the present case has a flexible element 97 and a dimensionally stable element 99.

The flexible element 97 is preferably designed with an elastomer and, for example, as an elastomeric membrane. In the present case, the flexible element 97 has a U-shaped cross section with two regions 101 and 103 running essentially in the vertical direction Y, which are connected by means of a region 105 running in the longitudinal direction Z. In the present case, the U-shaped cross section is essentially opened upwards in the vertical direction Y. In an alternative embodiment, the U-shaped cross section can also be opened essentially downwards in the vertical direction Y.

The flexible element 97 is connected to the dimensionally stable element 99 via a form fit and/or material fit, with the flexible element 97 being connected to the drive housing 91 by means of a form fit. For this purpose, the flexible element 97 in the present case has a first region 109 connected to the region 101, which is designed, for example, as a circumferential nose, the nose 109 being able to be brought into operative connection with a groove 113 of the drive housing 91.

The dimensionally stable element 99 is designed, for example, as a plastic frame, by means of which the sealing device 87 can be fixed to the housing 5. For this purpose, the housing 5 for example, a groove 107 which runs around in particular with respect to the vertical axis Y, into which the dimensionally stable element 99 can be inserted and fixed with a second region 111.

To connect the plate-shaped, dimensionally stable element 99 to the flexible element 97, the flexible element 97 has a recess 115 which points outwards in the radial direction with respect to the vertical direction Y, into which the dimensionally stable element 99 engages with an edge region.

The first area 109 is arranged further up in the vertical direction Y with respect to the recess 115. This makes it possible, in particular, to compensate for a large displacement of the assembly 9 relative to the housing 5 in the longitudinal direction Z. In alternative embodiments, the first area 109 and the recess 115 can also lie at approximately the same height in the vertical direction Y, depending on the general conditions, or the first area 109 can be arranged further down than the recess 115.

In Fig. 6 the assembly 9 is in the middle position according to Fig. 3 opposite the housing 5 shown. The flexible element 97 is in an undeformed and in particular not strained position. This has the advantage that the flexible element 97 is not deformed to an undesirably large extent and is not exposed to undesirably large stretches and stresses, both when it is in the front end position and when it is in the rear end position relative to the housing 5, and does not have a sealing effect is impaired.

In Fig. 13 and Fig. 14 For example, a deformation of the flexible element 97 is shown, which the flexible element 97 assumes when the assembly 9 is in the front end position relative to the housing 5.

Claims (12)

Machine tool (1), in particular a hammer drill or chisel hammer, with a housing (5) having a handle area (7, 27) and an assembly (9) comprising an impact mechanism (11) and a drive device (13), the assembly (9) is arranged essentially within the housing (5) and is arranged to be movable relative to the housing (5), a center of gravity (15) of the assembly (9) being arranged at a distance from an impact axis (19), characterized in that a partitioning device (87 ) is provided to restrict an air flow between the assembly (9) and the housing (5), the isolation device (87) being connected to the assembly (9) and to the housing (5) and the assembly (9) with respect to one Vertical direction (Y) of the machine tool (1) circumferentially encompasses. Machine tool according to claim 1, characterized in that the isolation device (87) is connected to the housing with a first region (109) and is connected to the module with a second region (111). Machine tool according to claim 1 or 2, characterized in that the partitioning device (87) has a flexible element (97) and a dimensionally stable element (99). Machine tool according to claim 3, characterized in that the flexible element (97) has at least two regions (101, 103) which run essentially in the vertical direction and which are connected to one another in the longitudinal direction (Z). Machine tool according to one of the preceding claims, characterized in that the partitioning device (87) has an area which is U-shaped in cross section. Machine tool according to one of the preceding claims, characterized in that the isolation device (87) is connected to the assembly (9) and/or the housing (5) via a positive connection and/or material connection. Machine tool according to one of claims 2 to 6, characterized in that the isolation device (87) with the first area (109) and/or second area (111) in a recess (107, 113) of the housing (5) or the assembly (9) intervenes. Machine tool according to one of claims 2 to 7, characterized in that the flexible element (97) surrounds the dimensionally stable element (99) in the circumferential direction of the vertical direction (Y). Machine tool according to one of claims 3 to 8, characterized in that the flexible element (97) is made with an elastomer. Machine tool according to one of claims 3 to 9, characterized in that the dimensionally stable element (99) is made of a plastic Machine tool according to one of the preceding claims, characterized in that the partitioning device (87) is designed such that it allows a movement of the assembly (9) relative to the housing (5) in the longitudinal direction (Z) of greater than 0.8 mm, in particular greater than 1 .0 mm allows. Machine tool according to one of the preceding claims, characterized in that the partitioning device (87) is in a neutral position when the assembly (9) is approximately centrally located between two end positions with respect to the housing (5) in relation to the longitudinal direction (Z). position is.

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