EP2429771B1 - Hand-held power tool, in particular electric hand-held power tool - Google Patents

Description

The invention relates to a handheld power tool, in particular an electric handheld power tool, according to the preamble of claim 1 DE 10 2006 027 774 A1 forth.

State of the art

In the DE 10 2005 016 453 A1 describes an angle grinder, whose motor housing is connected to a rear housing cover, through the bottom of which a cable grommet is led to supply the electrical drive motor with power. The housing cover is pot-shaped, with a circumferential sealing ring inserted between the facing end faces of the motor housing and the housing cover, which effectively dampens vibrations in the axial and radial directions, which emanate from the electric drive motor and possibly arise when machining a workpiece.

The EP 1 533 084 A1 shows an electric hand drill with a tool housing, to which a bow-shaped handle connects in the rear area, the front ends of which are connected to the tool housing. At the bottom of the tool housing there is a base part which can be screwed onto the tool housing. At one end the bow-shaped handle has a bearing axis which is enclosed by a damping ring, the bearing axis being able to be supported with the damping ring in bearing shell sections which are located on the tool housing or on the base part.

Disclosure of the invention

Starting from this prior art, the invention is based on the object of reducing the noticeable vibrations in a handheld power tool, that spread from a drive unit or arise during the machining of a workpiece and propagate into the housing of the hand tool.

This object is achieved with the features of claim 1. The subclaims indicate appropriate further training.

According to the invention, a housing of a handheld power tool is provided with at least two separate housing parts to be connected to one another, wherein a housing part forms a handle housing for holding and guiding the hand machine tool. A vibration reduction element is arranged between the housing parts. Furthermore, it is provided that the handle housing consists of at least two separately designed handle housing parts, which are designed as a handle and as a fastening component, the fastening component being connected on the one hand to the further housing part and on the other hand to the handle. A vibration reduction element is arranged between the fastening component and the handle.

This embodiment has the advantage that the handle can be at least largely decoupled from oscillations and vibrations that originate from the drive unit or arise during the machining of a workpiece. The handle is connected to the further housing part - which is usually the motor housing - at least in one spatial dimension via the fastening component. For vibration decoupling, the vibration reduction element is arranged between the fastening component and the handle, preferably in the axial direction in which the fastening component secures the handle. The vibration reduction element lies in the transmission chain from the further housing component via the fastening element to the handle, so that the vibration transmission from the fastening component to the handle is at least reduced.

At the same time, this version offers the possibility of designing the direct contact between the handle and the further housing part in such a way that no vibrations are transmitted, or only in a reduced manner, via this path. Fasteners which connect the handle to the further housing part can be dispensed with. If necessary, such fastening means for fastening the handle to the further housing components can still be considered.

According to a preferred embodiment, a further vibration reduction element is provided between the handle and the further housing component, which has a supporting effect since the handle is supported on the further housing part via this additional vibration reduction element. Despite the support, vibrations that spread in the further housing part are only transmitted to the handle in a reduced manner.

Overall, these measures result in a significantly reduced vibration load on the handle, which improves the comfort for the operator and reduces the workload. The division of the handle housing into a handle on the one hand and a fastening component on the other hand allows additional creative or constructive freedom and allows a variety of arrangement of vibration reduction elements between the fastening component and the further housing part and / or between the fastening component and the handle and possibly between the handle and the further housing part.

The further housing part is preferably a motor housing in which a drive unit, in particular an electric drive motor for driving the tool of the hand-held power tool, is accommodated. If necessary, further components are accommodated in the motor housing, for example electronic components, switches etc. The handle housing forms, for example, a housing cover and, according to the invention, is made in two parts with the handle and the fastening component, the fastening component being connected directly to the motor housing, so that forces between the fastening component and are transferable to the motor housing. The fastening component also secures the handle in the desired position with respect to the motor housing.

According to the invention, the handle forms a grip sleeve which surrounds the further housing part, with the fastening component expediently forming the bottom or part of the bottom in this embodiment, so that the handle and the fastening component are designed together in a pot shape in the assembled state. The grip sleeve encloses the further housing part and can be gripped in an ergonomically favorable manner by the operator for holding and guiding the handheld power tool. The fastening component as the bottom of the pot-shaped housing cover, which forms the handle, is positioned on the axial end of the motor housing and is expediently connected to the end of the motor housing. For this purpose, non-positive, material and / or positive measures can be considered, for example screwing the fastening component onto the end face of the motor housing. If necessary, the fastening component can also be glued.

According to an advantageous embodiment, which can be realized in a simple manner, there is only a vibration reduction element between the fastening component and the handle, but not between the fastening component and the motor housing. The vibrations transmitted from the motor housing to the fastening component can only spread to the handle in a reduced manner.

However, it can be expedient to provide an additional vibration reduction element between the motor housing and the fastening component, so that at least two vibration reduction elements are arranged in total in the transmission chain from the motor housing to the fastening component and further to the handle. As a result, an improved vibration reduction in the handle is achieved.

The vibration reduction element arranged between the fastening component and the handle acts in the axial direction and / or in the radial direction and dampens or reduces in this direction the vibrations to which the fastening component is subjected. An optionally provided vibration reduction element between the further housing part and the fastening component also exerts its effect in the axial and / or in the radial direction.

According to an advantageous embodiment, it is provided that the vibration reduction element is arranged in the axial direction between an end edge of the fastening component and the handle and is accordingly effective in the axial direction. A further vibration reduction element can be arranged axially between an opposite end edge of the handle and a shoulder of the motor housing, so that the handle is delimited axially on opposite sides by a vibration reduction element in each case. This reduces both the transmission of vibrations from the fastening component to the handle and from the motor housing to the handle.

Various designs are possible for the vibration reduction element. The vibration reduction element can be designed as a damping element be, which dissipates energy contained in the vibrations, so that vibrations are transmitted to the handle only in a reduced manner. Vibration-reducing materials such as elastomers, rubber or rubber-like materials, foams, gels or the like are preferably used for this. Material-damping components are preferably used, although movement-damping components can in principle also be used.

According to a further embodiment, it is provided that at least one vibration reduction element is designed as a spring element. Due to the spring action of the vibration reduction element, vibrations and vibrations that originate from a component are passed on to the adjacent component with respect to frequency and amplitude in reduced or modified form, whereby an effective reduction of the vibration load in the handle can also be achieved, in particular one Shift from critical to uncritical frequencies. Separately designed spring elements can be used as the spring element, for example coil springs or leaf springs, which are arranged between the fastening component and the handle or are located between the motor housing and the fastening component or between the handle and the motor housing. However, in a further embodiment, the spring elements can also be formed in one piece with a housing part, for example as a resilient projection which rises above the surface of a housing part and is in contact with a further housing part.

A combination of spring elements and damping elements may also be considered as vibration reduction elements.

According to a further advantageous embodiment, the handle housing has a double-shell or double-walled design, in that the fastening component forms an inner grip sleeve which is directly connected to the motor housing, and the handle forms the outer grip sleeve which is located at a radial distance from the inner fastening component. so that an annular space is formed as an intermediate space between the sleeve-shaped, internal fastening component and the sleeve-shaped, external handle. At least one vibration reduction element is preferably arranged in the annular space, to at least weaken a vibration transmission from the motor housing via the internal fastening component to the external handle. The internal fastening component can, on the other hand, be firmly connected to the motor housing, wherein vibrations transmitted to the fastening component do not lead to an increased vibration load on the operator due to the decoupling of the handle. The intermediate space can advantageously be used to accommodate the vibration reduction elements, so that no additional installation space is required for the installation of vibration reduction elements.

Various types of vibration reduction elements can be arranged in the intermediate space. Both damping elements, in particular elements with material damping properties, are also considered, ie also spring elements that change the amplitude and the frequency of the transmitted vibrations. A mixed application of damping and spring elements can also be considered. In a further embodiment, the vibration reduction element is designed as a gas pressure spring, in which a gas volume is enclosed by sealing elements which are arranged in the space between the fastening component and the handle.

The vibration reduction elements in the annular space cause vibration damping both in the radial direction and in the axial direction. In order to increase the vibration damping effect in the axial direction, it may be expedient to align at least one vibration reduction element with an additional axial component in the intermediate space, for example in such a way that a helical spring is positioned obliquely in the intermediate space, so that the spring axis both with the radial direction and with the axial direction encloses an angle.

Distributed over the axial length, a plurality of vibration reduction elements are expediently arranged in the annular intermediate space in order to ensure that there is uniform support of the outer handle on the inner fastening component over the axial length.

The external handle is preferably supported exclusively via vibration reduction elements in order to avoid vibration transmission bridges.

Furthermore, it may be expedient that the outside handle is positively secured to the inside fastening component. This is realized, for example, in that a radially inwardly projecting latching projection is formed on the handle, to which a radially outwardly facing latching projection is assigned on the outside of the fastening component. The radial locking projections are axially slightly offset from one another, they can directly adjoin one another axially, so that it is reliably prevented that the handle is accidentally detached axially from the handheld power tool. However, in order to enable the handle to be pushed open or removed for maintenance purposes, a bayonet lock can be used, for example.

According to a further aspect of the invention, the hand-held power tool has at least two separate housing parts to be connected to one another, one housing part forming a grip part for holding and guiding the hand-held power tool and a damping element being arranged between the housing parts. The damping element is formed in one piece with a cable grommet, which encloses an electrical power cable, which is guided into the housing for the power supply of an electric drive motor of the hand-held power tool.

In this embodiment, the cable grommet, which usually consists of a material-damping material such as elastomer, is also used for vibration damping or vibration reduction, thereby simplifying the construction and reducing the number of components. Since the power cable for power supply is usually inserted into the motor housing via the rear end, the damping element is also located on the rear end of the motor housing and can be connected to the handle in the sense of a fastening component, so that the handle is attached to the damping element and in one piece the damping element formed grommet is secured in at least one axial direction based on the motor housing.

Fig. 1

ein nicht erfindungsgemäßes Ausführungsbeispiel einer Handwerkzeugmaschine mit einem mehrteiligen Gehäuse, welches als erstes Gehäuseteil ein Motorgehäuse und als weiteres Gehäuseteil ein zweiteiliges Griffgehäuse umfasst, wobei das Griffgehäuse aus einem hülsenförmigen Handgriff und einem stirnseitigen Befestigungsbauteil besteht, welches mit der Stirnseite des Motorgehäuses verbunden ist, wobei zwischen dem Befestigungsbauteil und dem Handgriff ein Dämpfungselement angeordnet ist,

Fig. 2

ein weiteres nicht erfindungsgemäßes Ausführungsbeispiel einer Handwerkzeugmaschine, bei der der Handgriff über eine Blattfeder mit dem Motorgehäuse verbunden ist,

Fig. 3

ein weiteres nicht erfindungsgemäßes Ausführungsbeispiel, bei dem einteilig mit dem Motorgehäuse Federelemente zur Sicherung des Handgriffs und des Befestigungsdeckels ausgebildet sind,

Fig. 4

ein erfindungsgemäßes Ausführungsbeispiel, bei dem an der Außenseite des Motorgehäuses Federelemente angeformt sind, welche den Handgriff beaufschlagen, wobei am Handgriff weitere Federelemente angeformt sind, an denen das unmittelbar mit dem Motorgehäuse verschraubte Befestigungsbauteil anliegt,

Fig. 5

ein weiteres erfindungsgemäßes Ausführungsbeispiel, bei dem eine Kabeltülle, welche ein Stromkabel einfasst, einteilig mit einem Dämpfungselement ausgebildet ist,

Fig. 6

ein weiteres erfindungsgemäßes Ausführungsbeispiel, bei dem die Kabeltülle und das Dämpfungselement als separate Bauteile ausgebildet sind,

Fig. 7

ein weiteres nicht erfindungsgemäßes Ausführungsbeispiel, bei dem das Griffgehäuse doppelschalig ausgeführt ist, wobei das Befestigungsbauteil eine innen liegende Griffhülse und der Handgriff eine dazu beabstandete, außen liegende Griffhülse bildet, und wobei zwischen innen liegendem Befestigungsbauteil und außen liegendem Handgriff Dämpfungselemente angeordnet sind,

Fig. 8

ein nicht erfindungsgemäßes Ausführungsbeispiel mit einer ebenfalls doppelwandigen Ausführung des Griffgehäuses, wobei zwischen innen und außen liegender Griffhülse Federelemente angeordnet sind,

Fig. 9

ein nicht erfindungsgemäßes Ausführungsbeispiel ähnlich wie Fig. 8, jedoch mit schräggestellten Federelementen im Zwischenraum zwischen innen und außen liegender Griffhülse,

Fig. 10

ein weiteres nicht erfindungsgemäßes Ausführungsbeispiel mit einem doppelwandigen Griffgehäuse, mit verschiedenen als Blattfedern ausgebildeten Federelementen im Zwischenraum zwischen den Griffhülsen,

Fig. 11

ein nicht erfindungsgemäßes Ausführungsbeispiel, bei dem im Zwischenraum eine Blattfeder angeordnet ist, welche einteilig mit der Wandung des außen liegenden Handgriffes ausgebildet ist,

Fig. 12

ein nicht erfindungsgemäßes Ausführungsbeispiel, bei dem im Zwischenraum ein Gasvolumen liegt,

Fig. 13

ein nicht erfindungsgemäßes Ausführungsbeispiel, bei dem im Zwischenraum fluidgefüllte Dämpfungselemente angeordnet sind,

Fig. 14

ein nicht erfindungsgemäßes Ausführungsbeispiel, bei dem im Zwischenraum ein Gasvolumen druckdicht eingeschlossen ist,

Fig. 15

ein nicht erfindungsgemäßes Ausführungsbeispiel ähnlich wie Fig. 14, jedoch mit einem verbindenden Drosselkanal zwischen zwei separierten Gas- oder Fluidvolumina im Zwischenraum.

Further advantages and expedient designs can be found in the further claims, the description of the figures and the drawings. Show it:

Fig. 1

a non-inventive embodiment of a hand tool with a multi-part housing, which comprises a motor housing as the first housing part and a two-part handle housing as the further housing part, the handle housing consisting of a sleeve-shaped handle and an end-side fastening component which is connected to the end face of the motor housing, with between a damping element is arranged on the fastening component and the handle,

Fig. 2

another exemplary embodiment of a hand-held power tool, in which the handle is connected to the motor housing via a leaf spring,

Fig. 3

a further embodiment not according to the invention, in which spring elements for securing the handle and the fastening cover are formed in one piece with the motor housing,

Fig. 4

an exemplary embodiment according to the invention, in which spring elements are formed on the outside of the motor housing, which act on the handle, with further spring elements being formed on the handle, against which the fastening component screwed directly to the motor housing rests,

Fig. 5

a further exemplary embodiment according to the invention, in which a cable grommet which encloses a power cable is formed in one piece with a damping element,

Fig. 6

another embodiment according to the invention, in which the cable grommet and the damping element are designed as separate components,

Fig. 7

a further embodiment not according to the invention, in which the handle housing is designed with a double shell, wherein the fastening component forms an inner grip sleeve and the handle forms a spaced outer grip sleeve, and wherein between the inner fastening component and damping elements on the outside are arranged,

Fig. 8

an embodiment according to the invention with a likewise double-walled design of the handle housing, spring elements being arranged between the inside and outside handle sleeve,

Fig. 9

an embodiment not according to the invention similar to Fig. 8 , but with inclined spring elements in the space between the inside and outside grip sleeve,

Fig. 10

another embodiment not according to the invention with a double-walled handle housing, with various spring elements designed as leaf springs in the space between the handle sleeves,

Fig. 11

an embodiment according to the invention, in which a leaf spring is arranged in the intermediate space, which is formed in one piece with the wall of the outside handle,

Fig. 12

an embodiment according to the invention, in which there is a gas volume in the intermediate space,

Fig. 13

an embodiment not according to the invention, in which fluid-filled damping elements are arranged in the intermediate space,

Fig. 14

an embodiment according to the invention in which a gas volume is enclosed in a pressure-tight manner in the intermediate space,

Fig. 15

an embodiment not according to the invention similar to Fig. 14 , but with a connecting throttle channel between two separated gas or fluid volumes in the space.

The same components are provided with the same reference symbols in the figures.

In the Fig. 1 Electric hand machine tool shown, for example an angle grinder or an electric drill or screwdriver, has a housing, consisting of a motor housing 2, in which an electric drive motor 3 is arranged, and a handle housing 4, which is connected to the motor housing 2. The handle housing 4 is constructed in two parts and consists of a handle 5 and a fastening component 6. The handle 5 is designed as a grip sleeve which is pushed onto the rear section of the motor housing 2 and surrounds it in a ring. The fastening component 6 is located on the rear axial end face 7 of the motor housing 2. The sleeve-shaped handle 5 and the fastening component 6 together form a handle pot which is pushed onto the motor housing 2. The fastening component 6 is designed in the form of a disk and has an axially projecting wall section 6a which extends in the direction of the handle 5. The fastening component 6 is firmly connected to the rear end face 7 of the motor housing 2. In particular, the fastening component 6 lies directly on the end face 7.

The axially projecting section 6a of the fastening component 6 supports the handle 5 and applies an axial supporting force to it. However, the free end face of the wall section 6a of the fastening component 6 is not in direct contact with the handle 5, but there is a damping element 8 between the handle 5 and the fastening component 6, which has the function of damping vibrations which arise from the motor housing 2 Spread out over the fastening component 6. The damping element 8 is designed, for example, as a damping ring which extends along the outer jacket of the motor housing 2. However, an embodiment is also possible in which the damping element is not designed in the form of a ring, but rather only as a segment, in which variant a plurality of individual damping elements are preferably provided distributed over the circumference between the fastening component 6 and the handle 5.

In particular in the embodiment as a ring, the damping element 8 is seated in a contoured, ring-shaped circumferential seat 9, which is integrally formed on the outer casing of the motor housing 2.

The damping element 8 lies between the end face of the axial wall section 6a of the fastening component 6 and a radially inwardly extending extension 10 which is formed in one piece on the handle 5. The damping element 8 transmits support forces in the axial direction and also unfolds its damping effect in the axial direction. Various materials come into consideration as the material for the damping element, for example elastomers, rubber or gels or the like.

On the side axially opposite the first damping element 8 there is a further damping element 11 on the handle 5, which is clamped axially between a radially inwardly projecting extension 12 on the handle 5 and a shoulder 13 on the motor housing 2 and transmits supporting forces in the axial direction as well its damping effect unfolds in the axial direction. The shoulder 13 on the motor housing 2 is designed in particular as a circumferential ring shoulder. The damping element 11 is preferably designed as the damping element 8 as a damping ring.

Expediently seen in the radial direction, the extent of the damping elements 8 and 11 is greater than the extent of the inwardly projecting extensions 10 and 12, so that the free end faces of the extensions 10 and 12 are not in contact with the outer lateral surface of the motor housing 2 and a direct contact between the handle 5 and the motor housing 2 is avoided. This ensures that there is no direct vibration transmission from the motor housing 2 to the handle 5. The radial distance is determined on the one hand by the radial extent of the damping elements 8 and 11 and on the other hand by the radial extent of the seat 9, which is arranged on the outside of the motor housing 2 and serves to receive the damping element.

The connection between the fastening component 6 and the end face 7 on the motor housing 2 takes place via common fastening measures, for example by screwing. It may be appropriate to arrange a further vibration reduction element between the end face 7 and the fastening component 6.

In the embodiment according to Fig. 1 the vibration reduction elements are designed as damping elements 8 and 11. In principle, however, spring elements can also be used instead of the damping element, which can also have a vibration-reducing effect, or at least a frequency shift in the direction of non-critical frequencies.

In the annular space between the outer casing of the motor housing 2 and the inside of the handle 5, which due to the radially projecting extensions 10 and 12 and the damping elements 8 and 11 is at a distance from the outer surface, there can be an absorber element 14. The absorber element 14 is in particular firmly connected to the handle 5 and serves to increase the moment of inertia of the handle 5, as a result of which both the frequency and the amplitude of the vibrations acting on the handle 5 are changed. By choosing a corresponding damper element 14, the vibration load acting on the handle can be reduced in this way.

The absorber mass 14 is preferably fixedly and immovably connected to the handle 5. According to an alternative embodiment, however, it can also be expedient that the damper mass 14 is connected to the handle 5, but can perform a relative movement with respect to the handle 5. In this way, an oscillatable two-mass system with an intermediate spring element is achieved, which also changes both the frequency and the amplitude of the vibrations of the handle 5.

In the embodiment according to Fig. 2 the sleeve-shaped handle 5 is connected to the axially rear end face 7 of the motor housing 2 by means of a spring element 15. The spring element 15 is designed as a leaf spring, which is angular and extends with a section on the end face 7 of the motor housing 2 and with an angled section in the axial direction. The angled section 15a has a radially outward projection in the region of its free end face, which protrudes into a groove on the inside of the handle 5, so that there is a positive connection in the axial direction between the section 15a of the spring element 15 and the handle 5 . In general, however, other connection measures between the spring element 15 and the handle 5 can also be considered in order to secure the handle 5 in the axial direction or to achieve a vibration reduction in the axial direction and possibly also in the radial direction due to the spring action. In this exemplary embodiment, the fastening component 6 has the function of covering the end face 7. The section 6a of the fastening component 6 which extends in the axial direction is expediently connected to the handle 5, a damping element being seen between the free one in the axial direction Front side of the section 6a and an extension projecting radially inwards on the inside of the handle 5 can be arranged.

In the embodiment according to Fig. 3 spring elements 16, 17 and 18 are molded onto both the outer casing of the motor housing 2 and the rear, axial end face 7. These spring elements 16, 17 and 18 are formed in one piece with the motor housing and rise finger-shaped over the lateral surface or the rear end face of the motor housing. The two spring elements 16 and 17 on the outer casing of the motor housing 2 act on the inside of the sleeve-shaped handle 5 and thereby transmit a clamping force in the radial direction. In addition, the spring elements 16 and 17 can cooperate with a shaped seat on the inside of the handle 5, whereby a positive connection is achieved in the axial direction, so that forces can also be transmitted in the axial direction. The free end face of the finger-shaped spring elements 16 and 17 extend in opposite directions, the rear spring element 17 being directed in the direction of the rear end face 7.

A further spring element 18 is formed on the rear end face 7 and acts axially on the fastening element 6. The free end faces of the spring element 18 extend in the radial direction and lie in the assembled position in a latching recess which is delimited on the one hand by the inside of the lid-shaped fastening element 6 and on the other hand by a radially inwardly projecting extension 19.

The spring elements 16 and 17 on the outer surface of the motor housing 2 can extend in a ring in the circumferential direction on the outside of the motor housing. However, it is also possible to have a single, segmented spring element.

In the embodiment according to Fig. 4 the fastening component 6 is designed as a base plate which is screwed to the end face 7 of the motor housing 2 by means of a screw 21. The fastening component 6 acts in the axial direction on a spring element 20 which extends radially inwards on the inside of the sleeve-shaped handle 5 and is integrally formed on the handle 5. The spring element 20 generates an axial force, which is directed against the contact pressure, which with the aid of the screw 21 over the fastening component 6 is reached. The axial force presses the handle 5 axially against the shoulder 13 on the motor housing 2, so that the handle 5 is secured in the axial direction in both directions via the fastening component 6.

In addition, the radially rising spring elements 16 and 17 integrally formed on the outer casing of the motor housing 2 act on the handle 5 in the radial direction.

The spring element 20 formed on the inside of the handle 5 is expediently not annular, but extends only over a limited angular section. On the side diametrically opposite the spring element 20, a groove is formed on the inside of the handle 5, into which the edge region of the plate-shaped fastening component 6 projects.

In the embodiment according to Fig. 5 a power cable 23 is arranged on the rear axial end face 7 of the motor housing 2 and is used in the interior of the motor housing to supply power to the electric drive motor placed there. The power cable 23 is surrounded by a cable grommet 22, which consists of a resilient material that has vibration-damping properties. A damping element 24 is formed in one piece with the cable grommet 22, which is disk-shaped or ring-shaped and whose radial outside lies in contact with the inner wall of the handle 5 in the region of the free end face of the handle. On the inside of the handle 5, an extension 10 is also formed, which is acted upon axially by the damping element 24.

In the recess, which is introduced into the annular damping element 24, the cover or plate-shaped fastening component 6 is inserted, which is screwed to the end face of the motor housing 2 via a screw 21. The fastening component 6 acts on the damping element 24 in the axial direction and presses it in the direction of the front side 7 of the motor housing against the extension 10 on the inside of the handle 5.

On the side opposite the cable grommet 22 there is a further damping element 11 on the free end face of the handle 5, which is clamped between the end face of the handle 5 and the annular shoulder 13 on the motor housing 2.

In the embodiment according to Fig. 6 are the cable grommet 22, which surrounds the power cable 23, and the damping element 24 are formed as separate components. Both the cable grommet 22 and the damping element 24, which are each arranged on the end face 7, are clamped axially by the plate-shaped fastening component 6, which is screwed onto the end face 7 of the motor housing 2 by means of the screw 21. The cable grommet 22 and the damping element 24 are pressed axially by the pressure of the fastening element 6 against the radially inwardly projecting extension 10 formed on the inside of the handle 5.

On the side facing away from the damping element 24 there is a further damping element 25, which is ring-shaped, between the extension 10, which rotates in a ring on the inside of the handle 5, and the end face 7 of the motor housing 2.

In the exemplary embodiments according to FIGS Figures 7 to 15 the handle housing is also divided into two, however, the fastening component 6 forms an inner, pot-shaped handle sleeve which rests directly on the motor housing 2 or is connected to it. The handle 5 forms an outer grip sleeve which has a larger diameter than the fastening component 6 and is pushed onto the fastening component 6. Between the outer jacket of the fastening component 6 and the inner jacket of the handle 5, an annular space 26 is formed, which serves to accommodate vibration reduction elements.

How Fig. 7 can be seen, damping elements 8 are arranged in the space 26 as vibration reduction elements, the damping elements 8 each consisting of a material with vibration-damping properties. A plurality of such damping elements 8 are distributed over the axial length. The damping elements 8 can either be ring-shaped and extend over the circumference of the intermediate space 26 or, according to an alternative embodiment, can be segment-shaped.

The vibration reduction elements 8 in the space 26 of the Figures 7 to 15 on the one hand assume a vibration-damping function in order to relieve the outer handle 5 of vibrations which originate from the motor housing 2 and propagate into the fastening component 6. On the other hand, the vibration reduction elements also take on a supporting function in order to fix the sleeve-shaped handle 5 in the radial and possibly also in the axial direction in the desired installation position.

How Fig. 7 can be seen further, for the axial securing of the handle 5 on the hand-held power tool 1, locking projections 27 and 28 are formed on the inside of the handle 5 and the outside of the fastening component 6, respectively, which extend in the radial direction, the dimensions of the locking projections 27 and 28 in Radial direction are selected so that a positive connection is established in the axial direction. The locking projection 27 formed on the inside of the handle 5 is found at a greater axial distance from the end face of the hand tool than the second locking projection 28, which is molded onto the fastening component 6, so that the handle 5 cannot be released axially.

On the side opposite the rear, axial end face of the motor housing 2, the free end face of the fastening component 6 bears against the shoulder 13, which is formed on the motor housing 2.

In the embodiment according to Fig. 8 consist of the vibration reduction elements, which are arranged in the intermediate space 26 between the fastening component 6 and the handle 5, each of a spring element, for example a coil spring, which is subjected to pressure. The spring axis extends according to Fig. 8 in the radial direction. Due to the spring action in the radial direction, corresponding vibrations are changed according to their frequency and amplitude such that the overall vibration load in the handle 5 is reduced. The spring elements 15 also bring about a stabilization of the handle 5 in the axial direction.

A plurality of such spring elements 15 are arranged in the intermediate space 26 distributed over the axial length.

The embodiment according to Fig. 9 differs from the previous one in that the spring elements 15 are arranged at an angle and inclined in the intermediate space 26, in such a way that the longitudinal axis of the spring assumes an angle both in relation to the axial direction of the housing and in relation to the radial direction. Distributed over the axial length, possibly also distributed over the circumference, several such spring elements 15 are provided, axially spaced spring elements 15 being inclined at an angle in such a way that the radially inner end face of the spring elements 15, each coupled to the fastening element 6 is directed in the direction of the respective axial end face of the fastening component.

In the embodiment according to Fig. 10 the vibration reduction elements in the intermediate space 26 between the fastening component 6 and the handle 5 are each formed as leaf springs with a different geometric shape. A first spring element 16 is designed as a U-shaped leaf spring, a second spring element 17 has a wave shape. The U-shaped spring element 16 is only clamped in the intermediate space 26, it being possible in this case to dispense with additional fastening measures for the firm connection to the outside of the fastening component 6 or the inside wall of the handle 5; nevertheless, it may be appropriate to provide such fasteners.

The second, wave-shaped spring element 17 is connected via a fastening element to the wall of the fastening component 6 or the wall of the handle 5.

In the embodiment according to Fig. 11 the vibration reduction element is also designed as a spring element which is arranged in the intermediate space 26. Shown is a wave-shaped spring element 17, which is molded onto the inner wall of the handle 5 and is thus formed in one piece with the handle 5. On the fastening component 6 side, the spring element 17 is connected with the aid of a fastening means, for example with the aid of a screw.

In the embodiment according to Fig. 12 the space 26 is sealed gas-tight, so that the gas volume located in the space 26 is effective in the manner of a gas spring. The gas-tight closure is on the part of the free The end face of the fastening component 6 and the handle 5 is reached by means of an annular damping element 8 arranged adjacent to the shoulder 13 on the motor housing 2. The gas volume stabilizes the handle 5 in the desired position in relation to the motor housing 2 and the fastening component 6 and also causes vibration damping.

In the embodiment according to Fig. 13 are placed in the space 26 fluid cushions 30, which have the function of vibration reduction elements and also support the handle 5 radially and in the axial direction. The fluid cushions 30 can be filled with compressed gas, which results in a good elasticity of the fluid cushions. In principle, however, filling with liquid is also possible.

The fluid cushions 30 can be used in groove-shaped guide parts which are formed on the outside of the fastening component 6 or the inside of the handle 5 and in particular define the axial position of the fluid cushion 30 in a form-fitting manner.

In the embodiment according to Fig. 14 there are two separately formed gas volumes 31 and 32 in the intermediate space 26, which are separated or sealed off from one another or axially outward by sealing rings 6a, 6b and 5a. In the exemplary embodiment, the sealing rings 6a, 6b and 5a are formed in one piece with the fastening component 6 or the handle 5 and are each designed as radially rising rings. Basically, separately formed sealing rings can also be considered.

The three rings 6a, 6b and 5a are axially spaced from one another, so that a first gas volume 31 is enclosed between the ring 6a and the ring 5a and a second gas volume 32 is enclosed between the ring 5a and the ring 6b. When the handle 5 is axially displaced with respect to the fastening component 6, the pressure in the compressed gas volume increases or the pressure in the expanding gas volume decreases, as a result of which a corresponding axial restoring force is generated which tends to move the handle 5 from the elongated position to the starting position reset.

The embodiment according to Fig. 15 corresponds essentially to that Fig. 14 with the difference that a throttle channel 33 connecting the two fluid volumes 31 and 32 is guided through the sealing ring 5a. An exchange of the respective fluid volumes is possible via the throttle channel 33, with the throttling effect being able to achieve speed damping with regard to the axial movement of the handle 5 relative to the fastening component 6.

If necessary, the volumes 31 and 32 are in accordance with the exemplary embodiment 14 and 15 not filled with gas, but with a liquid.

Claims (15)

1. Hand-held power tool, in particular electric hand-held power tool, comprising a housing having at least two separate housing parts (2, 4) that are to be connected to one another, wherein one housing part constitutes a handle housing (4) for holding and guiding the hand-held power tool (1), and a vibration reduction element (8, 11, 15, 16, 17, 18, 24, 25) is disposed between the housing parts (2, 4), characterized in that the handle housing (4) consists of at least two separately realized handle housing parts, realized as a handle (5) and as a fastening component (6), wherein the fastening component (6) is a securing cover that bears axially, or at the end face, against the further housing part (2), in that the fastening component (6) is connected, on the one hand, to the further housing part (2) and, on the other hand, to the handle (5), and in that a vibration reduction element (24) is disposed between the fastening component (6) and the handle (5), wherein the handle (5) is realized as a handle sleeve enclosing the further housing part (2) .
2. Hand-held power tool according to Claim 1, characterized in that a vibration reduction element (24) is disposed axially between the handle (5) and the fastening component (6).
3. Hand-held power tool according to Claim 1 or 2, characterized in that a vibration reduction element (8, 11, 15, 16, 17, 18, 24, 25) is disposed axially between the handle (5) and the further housing part (2).
4. Hand-held power tool according to any one of Claims 1 to 3, characterized in that a vibration reduction element (8, 11, 15, 16, 17, 18, 24, 25) is disposed radially between the handle (5) and the further housing part (2).
5. Hand-held power tool according to any one of Claims 1 to 4, characterized in that at least one vibration reduction element (8, 11, 15, 16, 17, 18, 24, 25) is realized as a damping element (8, 11, 24, 25).
6. Hand-held power tool according to any one of Claims 1 to 5, characterized in that at least one vibration reduction element (8, 11, 15, 16, 17, 18, 24, 25) is realized as a spring element (15, 16, 17, 18, 20).
7. Hand-held power tool according to Claim 6, characterized in that the spring element (15, 16, 17, 18, 20) is realized so as to be integral with a housing part (2, 4).
8. Hand-held power tool according to any one of Claims 1 to 7, characterized in that at least one vibration reduction element is realized as a gas pressure spring (31, 32).
9. Hand-held power tool according to Claim 8, characterized in that the gas pressure spring is constituted by a volume of gas (31, 32) enclosed between sealing elements (5a, 6a, 6b) in the interspace (26) delimited by the handle (5) and the fastening component (6) .
10. Hand-held power tool according to any one of Claims 1 to 9, characterized in that one housing part constitutes a motor housing (2) for accommodating a drive motor (3) .
11. Hand-held power tool according to any one of Claims 5 to 10, characterized in that the damping element (8, 11, 24, 25) is realized so as to be integral with a cable bush (22) of an electric power cable (23) for supplying power to an electric drive motor (3).
12. Hand-held power tool according to Claim 11, characterized in that the damping element (8, 11, 24, 25) bears with the cable bush (22) against an end face of the further housing part (2).
13. Hand-held power tool according to Claim 11 or 12, characterized in that the damping element (8, 11, 24, 25) is realized in the form of a ring.
14. Hand-held power tool according to any one of Claims 11 to 13, characterized in that fastening to the further housing part (2) is effected through the damping element (8, 11, 24, 25).
15. Hand-held power tool according to any one of Claims 11 to 14, characterized in that the damping element (8, 11, 24, 25) is connected to the handle part (4).

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