EP1752257A2 - Hand tool with vibration reduction - Google Patents

Abstract

The hand tool appliance has a horizontal tool spindle (10) and a main housing (4) at least partly accommodating the spindle and defining a central housing plane containing the horizontal and vertical directions (Z,Y) and a handle housing (16) supported laterally, horizontally and vertically on the main housing by respective vibration reducing elements (40a, 56a - 40c, 56c).

Description

The invention relates to a hand tool, which generates vibrations during operation, such as in particular an electric hammer drill, a chisel or impact drill, a motor-driven saw, in particular a jigsaw or saber saw, or a separating or grinding device, in particular an angle grinder. The hand tool has a tool spindle extending in a horizontal direction. The tool spindle is at least partially accommodated in a main housing, which defines a housing mean plane, which is spanned for example by an axis of the tool spindle and a center of gravity. In addition to the horizontal direction, a vertical direction perpendicular to this direction is directed along the housing center plane. In addition, a lateral direction of the hand tool device is perpendicular to the housing center plane. Furthermore, the hand tool device has a handle housing which is supported on the main housing with a lateral intermediate position of a lateral vibration-reducing element.

Such hand tools are held with one hand on a main handle, which is formed on the handle housing. The vibrations occurring during operation on the main housing occur on the handle as a result of the vibration-reducing elements only with significantly reduced intensity, which allows a more comfortable operation of the hand tool over longer periods of time.

From the DE 3121882 is a hand tool known, in which two U-shaped support elements are provided on the housing and the main handle. The support elements of the housing are connected transversely to a longitudinal axis of the power tool via two rubber blocks each with the support elements of the main handle. As a result, the support members can move relative to each other when a force is exerted in the direction of the longitudinal axis. In addition, the support members are shaped so that they come into contact with an excessive rotation of the main handle relative to the housing with each other.

A disadvantage of this attachment of the main handle to the hand tool is that the rubber elements in their connecting direction between the support elements have a relatively large dimension or must be relatively soft to achieve as desired in the longitudinal direction sufficient vibration damping. However, this can lead to a poor penetration of the main handle on the housing and thus to poor leadership of the power tool in operation. And even if sufficient vibration damping is achieved in the longitudinal direction with good leadership stability, so it is not possible on the rubber blocks at the same time in the two directions perpendicular to the longitudinal direction to achieve a comparatively good vibration damping while maintaining good leadership stability. However, this would be necessary in order to keep low with good penetration of the main handle on the housing to be included for the user on the main handle total vibration.

In addition, the proposed bonding of the rubber elements with the support elements and the assembly of the vibration damping elements on the power tool are relatively complex overall.

The present invention has for its object to avoid the disadvantages mentioned in a hand tool and to ensure a stable leadership with sufficient vibration reduction.

According to the invention, the object is achieved in that the handle housing is supported in addition to the lateral intermediate position of the lateral vibration reducing both under horizontal interposition of at least one horizontal vibration reduction element and under vertical intermediate layer of at least one vertical vibration reduction element on the main housing. In this way, the handle housing can be held in all three directions exclusively with the respective intermediate layer of a vibration-reducing element on the main housing. In this way, a separate vibration reduction can be set in each direction, in which a sufficiently stable mounting of the handle housing is maintained on the main housing without hard layer between the two housings. This makes it possible to minimize the overall vibration during operation of the handle housing and at the same time to ensure a stable guidance of the power tool.

In a preferred embodiment, in each case at least one pair of vibration-reducing elements which are spaced apart from each other in the respective direction is provided in the lateral direction, horizontal direction and vertical direction. This is supported by the Vibration reducing elements of each pair in the opposite direction between the handle housing and the main housing from.

In a particularly advantageous embodiment, the vibration-reducing elements of the respectively at least one respective pair are biased against each other in two directions from horizontal direction, vertical direction and lateral direction. As a result, in two holding directions of the handle housing on the main housing, a particularly high vibration damping at the same time particularly stable storage can be achieved.

It is particularly advantageous if in the horizontal direction, in the vertical direction and in the lateral direction, the vibration-reducing elements of the respective at least one respective pair are biased against each other. In this way, an optimal vibration damping of the overall vibration on the handle housing can be achieved, at the same time a stable mounting of the handle housing and thus an exact guidance of the power tool is made possible against all three directions.

Preferably, a triple-acting first damping body is provided, on which both the lateral vibration-reducing element and the horizontal vibration-reducing element and the vertical vibration-reducing element are formed. In this way, the number of elements required for the vibration damping can be further reduced and thus the assembly can be further simplified.

Advantageously, the elastic element in a vertical housing opening of a housing made of handle housing and main housing is held circumferentially and has a parallel to the housing opening extending recess. Through the recess protrudes an element of the other housing through, which may be formed, for example, peg-shaped or by any other projecting from one of the housing engagement contour. This circumferential liner allows a particularly stable storage of the handle housing to the main body.

It is particularly advantageous if the elastic element is supported in the vertical direction opposite to both housings. In this way, two vibration-reducing elements are provided on the elastic element in each of the three directions, which are supported oppositely between the two housings. As a result, a bias in all three directions can be generated on a single elastic element.

Advantageously, the vibration-reducing elements are at least partially made of a foamed plastic. As a result, even more complex shapes of the vibration-reducing elements or the damping body can be produced inexpensively.

• Die Erfindung wird nachstehend anhand eines Ausführungsbeispieles näher erläutert. Es zeigen:

  Fig. 1

  eine explodierte Seitenansicht eines erfindungsgemässen Handwerkzeuggerätes,

  Fig. 2

  eine teilweise freigeschnittene Seitenansicht des Handwerkzeuggerätes nach Fig.1,

  Fig.3

  einen Querschnitt durch eine Verbindungsanordnung des Handwerkzeuggerätes entlang der Ebene III-III aus Fig. 2,

  Fig. 4

  eine perspektivische Ansicht eines ersten elastischen Elementes der Verbindungsanordnung,

  Fig.5

  eine perspektivische Ansicht zweier zweiten elastischen Elemente der Verbindungsanordnung,

  Fig. 6

  eine Ansicht auf ein Griffgehäuse des Handwerkzeuggerätes in Richtung VI aus Fig. 1 und

  Fig. 7

  eine Draufsicht auf ein Hauptgehäuse des Handwerkzeuggerätes in Richtung VII aus Fig. 1.

The invention will be explained in more detail below with reference to an embodiment. Show it:

• The invention will be explained in more detail below with reference to an embodiment. Show it:

  Fig. 1

  an exploded side view of a hand tool according to the invention,

  Fig. 2

  a partially cutaway side view of the hand tool of Figure 1,

  Figure 3

  a cross-section through a connection arrangement of the power tool along the plane III-III of Fig. 2,

  Fig. 4

  a perspective view of a first elastic element of the connection arrangement,

  Figure 5

  a perspective view of two second elastic elements of the connection arrangement,

  Fig. 6

  a view of a handle housing of the power tool in the direction VI of FIG. 1 and

  Fig. 7

  a plan view of a main housing of the power tool in the direction VII of FIG. 1st

Fig. 1 shows a hand tool 2 in the form of a hammer drill with a substantially three-piece housing. In a main housing 4 while a motor 6 and a schematically illustrated gear 8 are housed. These drive a tool spindle 10 rotating and striking, which extends along a horizontal direction Z and on which a tool holder 14 is held against rotation.

On a handle housing 16, a handle 18 is formed over which the hand tool 2 is held with one hand, which simultaneously actuates a pusher 20 of a motor switch, not shown. The handle 18 extends substantially parallel to a vertical direction Y, which is perpendicular to the horizontal direction Z. In this case, the vertical direction Y and the horizontal direction Z lie in a housing center plane E, to which a lateral direction X is perpendicular, as can be seen from FIGS. 2 and 3.

It should be noted that the terms lateral direction X, vertical direction Y and horizontal direction Z were chosen only by way of example according to the illustrated hand tool 2. Depending on the type of hand tool 2, the directions mentioned may also be directed differently. Furthermore, the names may differ depending on the orientation of the hand tool 2 in space from the corresponding spatial directions.

Furthermore, a motor cover 22 is provided, which is formed separately from the main housing 4, and via which a housing opening 24 of the main housing 4 in the region of the motor 6 can be closed. This motor cover 22 can be fixed to the main housing 4 via screws 26 and extensions 27.

The handle housing 16 can be connected to the main housing 4 or to the motor cover 22 by means of a connecting arrangement designated overall by 28.

A first connection 50 has on the main housing side a convex engagement element 52 which protrudes on a gear housing 54 and can be engaged behind the interposition of a first elastic element 56 made of foamed plastic by a handle housing side rear grip element 58. For this purpose, the rear grip element 58 has a substantially concave receptacle 60, which is formed on the grip housing 16 and into which the first elastic element 56 can be inserted. This in turn forms a receiving space 62 which is open to one side and in which the convex engagement element 52 can be received, as can be seen in particular from FIG.

The first elastic element 56 is shown isolated in Fig. 4 in perspective. As indicated by dot-dash lines herein, the receiving space 62 is bounded in the lateral direction X by two portions of the first elastic member 56, each of which functions as a lateral vibration reducing member 56a. In the vertical direction Y, a portion is provided on the first elastic member 56, which as a vertical Vibration reduction element 56b acts. In the horizontal direction Z, a total of four regions are further formed on the first elastic element 56, each of which functions as a horizontal vibration-reducing element 56c.

The receiving space 62 has in the lateral direction X between the two lateral vibration-reducing elements 56a and in the horizontal direction Z between each two of the horizontal vibration-reducing elements 56c a slightly smaller extent than the respective extent of the convex engaging element 52 in each corresponding direction.

The connection arrangement 28 furthermore has four main housing-side locking receptacles 30 in the form of recesses which are provided on four housing webs 36 projecting from a rear side 34 of the main housing 4. As can be seen in particular from FIGS. 2 and 3, between each two of the housing webs 36 a molded on the handle housing 16 eyelet element 38 can be positioned. These eyelet elements 38 each have a handle-side locking receptacle 42 in the form of a continuous recess for receiving a second elastic element 40 made of foamed plastic. The second elastic elements 40 each have a passage recess 44. These passage recesses 44 can be brought into common alignment with the respectively adjacent main housing-side locking receptacles 30.

Furthermore, the connection arrangement 28 provides two peg-shaped latches 46, which protrude from the engine cover 22. The locking receptacles 30, 42 serve the second elastic elements 40 and the bars 46, as can be seen in particular from FIGS. 2 and 3, for producing a second connection 48 of the connection arrangement 28. This is perpendicular to the working axis 12 of the first connection 50 spaced apart.

In Fig. 5, the two second elastic elements 40 are shown isolated in perspective. As indicated by dot-dashed lines herein, the respective through-hole 44 is bounded in the lateral direction X by two respective regions of the second elastic elements 40, each of which functions as a lateral vibration-reducing element 40a. Furthermore, in the horizontal direction Z, two regions each are formed on the two second elastic elements 40, each of which functions as a horizontal vibration-reducing element 40c.

On both second elastic elements 40, a collar-shaped vertical vibration-reducing element 40b is further formed, which projects transversely to the vertical direction Y beyond the remaining second elastic element 40. In this way, the vertical vibration-reducing elements 40 each form on their two sides, relative to the vertical direction Y, an upper contact surface FO and lower contact surface FU extending transversely to the vertical direction Y.

During assembly of the hand tool 2, the first elastic element 56 is inserted into the receptacle 60 on the rear grip element 58, as shown in FIG. 6, on the handle housing side. Further, the second elastic members 40 are inserted into the handle-side locking receptacles 42 which are bolted to the handle housing 16.

Subsequently, the handle housing 16 is first brought into engagement with the convex engagement element 52 via the rear grip element 58 and the elastic element 56 inserted therein, as indicated in FIG. 1 by the mounting direction M1. Because of the above-described smaller dimensions of the receiving space 62 relative to the engaging element 52, the lateral vibration-reducing elements 56a and the horizontal vibration-reducing elements 56c in the receptacle 60 are biased in pairs against each other. The engagement element 52 is thus clamped on the handle housing 16 under lateral and horizontal interposition of the lateral vibration-reducing elements 56a and the horizontal vibration-reducing elements 56c.

Subsequently, the remote from the working axis 12 lower end of the handle housing 16 is pivoted along the mounting direction M2 to the first connection 50 to the main housing 4. The distance a between the vertical vibration-reducing element 56b of the first elastic element 56 in the unloaded state and the two upper contact surfaces FO of the second elastic elements 40 in the unloaded state shown in FIG. 6 is slightly less than the distance b, according to FIG. 7, between a Top edge 63 of the engaging member 52 and lower sides 65 of the respectively closer to the engaging member 52 positioned housing webs 36, with which the two upper contact surfaces FO come into contact during assembly. Thus, the first elastic member 56 must be acted upon with a certain voltage in the vertical direction Y in order to pivot the Ösenelemente 38 with the second elastic elements 40 held therein between the respective two housing webs 36 can.

In this way, the vertical vibration-reducing member 56b of the first elastic member 56 and the vertical vibration-reducing member 40b of the second elastic element 40 biased against each other and thus the engagement member 52 and the two closer thereto arranged housing webs 36 under vertical intermediate position of the vertical vibration-reducing element 56b and the vertical vibration-reducing element 40b between the receptacle 60 and the eyelet members 38 of the handle housing 16 clamped, as shown in Fig. 3 , At the same time, the through-hole 44 of the second elastic element 40 held in the grip-side locking receptacle 42 is brought into alignment with the main-housing-side locking receptacle 30.

At an edge 64, with which the handle housing 16 in this case comes into contact with the main housing 4 and the motor cover 22, an elastic seal 66 is provided to seal the interior of the housing against the outside, as can be seen from Fig. 1.

In a third assembly step, the motor cover 22 is then placed in the mounting direction M3 on the housing opening 24, as shown in particular in Fig. 5. Here, the latch 46 are pushed through the handle-side locking receptacles 42 and the second elastic members 40, whereby the handle-side locking receptacles 42 with the main housing-side locking receptacles 30 by means of the bolt 46 with the interposition of the respective second elastic member 40 are positively connected to each other.

The two passage recesses 44 have in the lateral direction X between the two lateral vibration-reducing elements 40a and in the horizontal direction Z between the two horizontal vibration-reducing elements 40c a slightly smaller extent than the respective extent of the latch 46 in each corresponding direction. Because of these smaller dimensions of the passage recesses 44 relative to the bolts 46, the lateral vibration-reducing elements 40a and the horizontal vibration-reducing elements 40c in the handle-side locking receptacles 42 are biased in pairs against each other. The bars 46 are thus clamped on the handle housing 16 under lateral and horizontal intermediate position of the lateral vibration-reducing elements 40a and the horizontal vibration-reducing elements 40c.

Overall, the handle housing 16 is thus in all three directions X, Y, Z exclusively under respective intermediate layer of mutually prestressed against each other vibration reduction elements 40a, 40b, 40c, 56a, 56b, 56c, that is without hard layer on Main housing 4 held. Thus, since the vibration reducing elements 40a, 40b, 40c, 56a, 56b, 56c are made of foamed plastic, in operation in all three directions X, Y, Z the vibration transmissions from the main body 4 to the handle housing 16 can be significantly dampened, thereby increasing the grip on the handle 18 occurring total vibration with stable leadership of the power tool 2 is significantly reduced.

The position of the motor cover 22 on the main housing 4 and thus also the achieved positive connection of the handle housing 16 with the main housing 4 finally secured at the second connection 48.

Simultaneously with the production of the positive connection at the second connection 48, the rear grip element 58 is held perpendicular to the working axis 12 so close to the engagement element 52, that it can not be pivoted past this. Thus, with the production of the positive connection at the second connection 48, a locking of the engagement on the first connection 50 takes place.

Claims (8)

Hand tool (2) which generates vibrations during operation,
with a in a horizontal direction (Z) extending tool spindle (10) and
a main housing (4) at least partially receiving the tool spindle (10), which defines a housing center plane (E) along which the horizontal direction (Z) and a vertical direction (Y) perpendicular thereto are directed and to which a lateral direction (X) of the Hand tool (2) is vertical, as well
a handle housing (16) which is supported on the main housing (4) with a lateral intermediate position of a lateral vibration-reducing element (40a; 56a),
characterized in that the handle housing (16) is also supported both under horizontal intermediate position of a horizontal vibration reduction element (40c, 56c) and under vertical intermediate position of a vertical vibration reduction element (40b, 56b) on the main housing (4). Hand tool according to Claim 1, characterized in that at least one pair of vibration-reducing elements (40a, 40b, 40c, 56a, 56b, 56c) spaced apart in the respective direction is provided in the lateral direction (X), horizontal direction (Z) and vertical direction (Y) wherein the vibration-reducing elements (40a, 40b, 40c, 56a, 56b, 56c) of each pair are supported in opposite directions between the handle housing (16) and the main housing (4). Hand tool according to claim 2, characterized in that in two directions from the horizontal direction (Z), vertical direction (Y) and lateral direction (X), the vibration reduction elements (40a, 40b, 40c, 56a, 56b, 56c) of the respective at least one pair are biased against each other , Hand tool according to claim 3, characterized in that in the horizontal direction (Z), in the vertical direction (Y) and in the lateral direction (X) the vibration-reducing elements (40a, 40b, 40c, 56a, 56b, 56c) of the respective at least one pair are biased against each other. Hand tool according to one of claims 1 to 4, characterized in that at least one triple-acting elastic element (40, 56) is provided on which both the lateral vibration- reducing element (40a; 56a) and the horizontal vibration-reducing element (40c; 56c) and the vertical vibration reducing element (40b, 56b) are formed. Hand tool according to claim 5, characterized in that the elastic element (40, 56) in a vertical housing opening of a housing of the handle housing (16) and the main housing (4) is held circumferentially and has a parallel to the housing opening extending recess through which an element (46, 52) of the respective other housing (4, 16) protrudes. Hand tool according to Claim 6, characterized in that the elastic element (40, 56) is additionally supported in the vertical direction (Y) on both housings (4, 16) in opposite directions. Hand tool according to one of claims 1 to 6, characterized in that the vibration-reducing elements (40a, 40b, 40c, 56a, 56b, 56c) are at least partially made of a foamed plastic.

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