EP1332023B1 - Hand machine tool comprising at least one handle - Google Patents

Description

State of the art

The invention relates to a hand tool with at least one handle according to the preamble of claim 1. Such a power tool is from the DE 195 30712 A known.
From the DE 87 01 722.9 U1 is a handle for guiding or holding swinging devices known. The handle has a handle with a metal core, which is coated with a vibration-damping plastic. With the metal core is connected at one end via a screw, a first metal sheet, which is connected in the remote from the handle portion axial direction via an elastic buffer with a second metal sheet. The second metal sheet is in turn connected via a screw to a guide tongue of the device.

Advantages of the invention

It is a hand tool with at least one handle, which has at least one handle part, which is fixedly connected via at least one elastic, vibration damping element with a fastening part, via which the handle part is fixed to a housing, proposed, wherein a connection between the handle part and the Fastening part is secured with the elastic element via at least one movable securing element, wherein the securing element is formed by a rigid component and the securing element is fixedly mounted in the fastening part and movable to the handle part and the securing element is fixedly connected to a fastening screw arranged in the fastening part.

Characterized in that a connection between the handle part and the fastening part is secured with the elastic element via at least one movable securing element, in a damage of the elastic element, a release of the handle part can be avoided by the housing and always ensured a control of the power tool on the handle part. Due to the movable design of the securing element, a vibration transmission via the securing element can be avoided in a normal operation. The fastening part is advantageously designed as a separate component to the housing, but may also be at least partially integral with the housing of the power tool.

If the securing element is formed by a rigid component, it can be movably mounted relative to the grip part. The fuse element can be easily installed and disassembled, so that it can be replaced after a damage.

The safety element is advantageously fixed in the fastening part and movably mounted to the handle part, whereby a space in the handle part advantageously used for freedom of movement of the fuse element and a simple assembly can be achieved from the handle part. Furthermore, a fixing screw arranged in the fastening part can be used for a firm connection of the securing element. Additional fasteners for the fuse element can be saved.

In order to protect the fuse element against damage during operation of the power tool and to be able to integrate the fuse element obscured in the handle, the elastic element advantageously surrounds the securing element.

It is also proposed that the Sicherungsclcmcnt is arranged centrally in the elastic element along a central axis, whereby undesired tensile stresses in the securing element and a vibration transmission associated therewith can be avoided during a tilting movement.

To protect the elastic member from external influences, this may also be enclosed with a sleeve of solid material which may be attached to the handle portion or on the fastening part and either to the handle portion or the fastening part has a distance to avoid vibration transmission.

Furthermore, a maximum deflection of the elastic element from a basic position, at least in a tilting direction and / or a thrust direction, can be determined in particular by means of the securing element, in particular via a rigid securing element. An overstretching the elastic element can be avoided by the securing element and a long service life can be achieved.

It is also proposed that the securing element is formed by a screw, which can be screwed particularly advantageous in the fastening screw in the fastening part. A screw is particularly cost-effective and can be easily and quickly assembled and disassembled. Instead of a screw but could also be used a bolt which can be either form-fitting, force, and / or cohesively fastened in the handle part or in the fastening part, for example, this can be pressed into the fastening screw in the fastening part.

In order to allow an advantageous uniform cooling, an advantageous homogeneous structure and an advantageous cohesive connection to the fastening part and / or to the handle part after an injection process of the elastic element, the elastic element has at least just before an advantageous circular bearing surface for fastening element and / or Handle part a non-circular cross-sectional area which is smaller than the contact surface, namely, the cross-sectional area is particularly advantageous from a circular core surface and radially to the core surface outwardly adjacent arcuate extensions together. With a round Kontor an advantageously large contact surface between the elastic element and the fastening element and the handle part can be achieved. By the adjoining smaller cross-sectional area of the contact area can be advantageously cooled.

Furthermore, an advantageous microstructure can be contributed by heat being removed from an inner region of the elastic element via at least one component during the production of the elastic element. The component can be formed by an already inserted in the production in the elastic element fuse element or advantageously of a core, which is removed after the production of the elastic element and advantageously forms a recess for the securing element. The core can advantageously be cooled relative to the inserted securing element by a cooling channel with a coolant. Especially with security elements, which are formed by rigid components and can be easily mounted after the production of the elastic element, a cooling of the elastic element in the production by a core is advantageous.

The solution according to the invention can be used in various hand-held power tools that appear appropriate to those skilled in the art, such as hammer drills, chipping hammers, drills, screwdrivers, saws, milling machines, planers, etc. However, the solution according to the invention can be used to advantage in angle grinders extending transversely to the longitudinal direction additional handle, which primarily serves to stir the angle grinder.

drawing

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

Fig. 1

einen schematisch dargestellten Winkelschleifer von oben,

Fig. 2

einen Handgriff mit einem von einem elastischen Element umschlossenen, biegeweichen Sicherungselement,

Fig. 3

einen Handgriff mit einem stabförmigen Sicherungselement,

Fig. 4

einen Ausschnitt einer Alternative zu Fig. 3,

Fig. 5

einen Schnitt entlang der Linie V-V in Fig. 4 bei der Montage,

Fig. 6

einen Handgriff mit einem von einem bandförmigen Sicherungselement umschlossenen elastischen Element,

Fig. 7

eine Variante zu Fig. 3,

Fig. 8

einen Schnitt entlang der Linie VIII-VIII in Fig. 7,

Fig. 9

einen Schnitt entlang der Linie IX-IX in Fig. 7,

Fig. 10

einen Schnitt entlang der Linie X-X in Fig 7,

Fig. 11

einen Schnitt entlang der Linie XI-XI in Fig. 7 und

Fig. 12

einen Handgriff nach Fig. 7 bei seiner Herstellung.

Show it:

Fig. 1

a schematically illustrated angle grinder from above,

Fig. 2

a handle having a flexible element enclosed by an elastic element,

Fig. 3

a handle with a rod-shaped securing element,

Fig. 4

a section of an alternative to Fig. 3 .

Fig. 5

a section along the line VV in Fig. 4 during installation,

Fig. 6

a handle with an elastic element enclosed by a band-shaped securing element,

Fig. 7

a variant too Fig. 3 .

Fig. 8

a section along the line VIII-VIII in Fig. 7 .

Fig. 9

a section along the line IX-IX in Fig. 7 .

Fig. 10

a section along the line XX in Fig. 7 .

Fig. 11

a section along the line XI-XI in Fig. 7 and

Fig. 12

a move behind Fig. 7 in its manufacture.

Description of the embodiments

Fig. 1 shows an angle grinder with a mounted in a housing 56, not shown electric motor, via which a clamped in a tool holder cutting disc 54 is driven. The angle grinder is integrated in the housing 56 on the side facing away from the cutting disk 54, extending in the longitudinal direction handle 58 and via a second attached to a gear housing 60 in the region of the cutting disk 54 and the tool holder, transversely to the longitudinal direction extending handle 10 feasible. The handle 10 has a handle portion 12 which is fixedly connected via an elastic, vibration-damping plastic element 14 with a fastening part 16, via which the handle portion 12 is attached via an integrally formed on the fastening part 16 threaded pin 18 on the gear housing 60 of the angle grinder. The elastic plastic element 14 is molded onto the handle part 12 and to the fastening part 16 and is thus firmly connected thereto.

The in the FIGS. 2 to 6 shown embodiments of the fuse element are for illustration and do not constitute components of the invention.

The grip part 12 is connected to the fastening part 16 next to the elastic plastic element 14 via a movable securing element 20 ( Fig. 2 ). The securing element 20 is formed by a flexible component in the form of a wire rope and is arranged in the elastic plastic element 14 along a central axis. At the ends of the Sicherungselemcnts 20 threaded sleeves are not shown attached, via which the securing element 20 is screwed to the handle part 12 and the fastening part 16. The elastic plastic element 14 encloses the securing element 20. The securing element 20 is loaded in the assembled state to train and the elastic plastic element 14 to pressure.

Fig. 3 shows a further embodiment of a handle 26, in which a securing element 22 is formed by a movably mounted rigid and molded by a resilient plastic member 24 rod, at the ends of each disc 30, 32 are attached. Essentially Constant components are numbered in the illustrated embodiments in principle with the same reference numerals. Regarding consistent functions and features can be found on the description of Fig. 1 to get expelled.

On the fastening part 16 and on the handle part 12 are each a sleeve 34, 36 attached, each having a disc 38, 40 with coaxial openings 42, 44 in the direction of the elastic plastic element 24. The sleeves 34, 36 and the discs 38, 40 respectively define a space 46, 48 which is ejected with elastic material and into which the securing element 22 with its discs 30, 32 is inserted. The discs 30, 32 of the securing element 22 have a larger diameter than the openings 42, 44 and are captively held in the spaces 46, 48.

For mounting, the disc 30 can be unscrewed from the rod-shaped part of the securing element 22. Subsequently, the securing element 22 before insertion of the sleeves 34, 36 with the handle part 12 and the fastening part 16 inserted into this and the disc 30 are screwed back to the rod-shaped part. The sleeves 34, 36 are connected via threaded connections not shown with the handle part 12 and the fastening part 16. After the sleeves 34, 36 are connected to the handle part 12 and the fastening part 16, the securing element 22 is encapsulated with elastic plastic.

The sleeves 34, 36 provide with their discs 38, 40 advantageously a positive connection between the handle part 12 and the elastic plastic element 24 and between the elastic plastic element 24 and the fastening part 16 ago. In principle, however, the elastic plastic element with the securing element, the sleeves and the discs could be designed as a preassembled module, which is then bolted to the handle part and the fastening part and glued.

By a freedom of movement of the discs 30, 32 of the securing element 22 in the spaces 46, 48, a maximum deflection of the elastic plastic element 24 is determined, in all directions. In order to avoid a vibration transmission via the securing element 22, the securing element 22 to the sleeves 34, 36 and the discs 38, 40 at a proper operation filled with elastic material distance.

In 4 and 5 another embodiment of a handle 62 is shown, in which a securing element 64 is formed by a movably mounted, rigid and overmolded by an elastic plastic element 24 rod whose ends 66, 68 are disc-shaped. Regarding consistent functions and features can be found on the description of Fig. 3 to get expelled.

On a fastening part 70 and on a handle part 72 are each a molded part 74, 76 are formed, which are each disk-shaped in the direction of the elastic plastic element 24 and coaxial openings 78, 80 have.

Each of the mold parts 74, 76 delimits a space 82, 84 which is ejected with elastic material and into which it is integrally formed executed fuse element 64 is inserted with its disc-shaped ends 66, 68 during assembly. In this case, the securing element 64 is guided with its rod-shaped part transversely to the longitudinal direction of the handle 62 through lateral openings 86, 88 of the molded parts 74, 76 ( Fig. 5 ). Subsequently, the securing element 64 in the mold parts 74, 76 secured against its insertion 90 through the openings 86, 88 by each in longitudinal section L-shaped moldings 92, 94 perpendicular to the insertion 90 and transverse to the longitudinal direction, each with an opening 96, 98 via the rod-shaped part of the fuse element 64 are pushed. The disc-shaped ends 66, 68 of the securing element 64 have a larger diameter than the openings 78, 80 and are captively held in the spaces 82, 84. Subsequently, the securing element 64 is encapsulated with plastic.

Advantageously, a width 100 of the openings 86, 88 transversely to the longitudinal direction of the handle 62 and perpendicular to the insertion direction 90 of the securing element 64 is made smaller than a diameter 102 of the rod-shaped part of the securing element 64, so that the securing element 64 against resistance through the openings 86, 88 must be pushed and then in the openings 78, 80 of the mold parts 74, 76 engages. The securing element 64 is secured in the openings 78, 80 of the molded parts 74, 76, and the mold parts 92, 94 can be advantageously saved.

Fig. 6 shows a further embodiment of a handle 50, in which a securing element 28 is formed by a flexible cloth band which encloses a resilient plastic element 52. The band-shaped securing element 28 is designed to be substantially inextensible in the longitudinal direction of the handle 50 and has the handle portion 12 and the fixing member 16 each have a plastic collar, not shown, with which the band-shaped securing element 28 is firmly connected via snap-in connections with the handle portion 12 and with the fastening part 16.

To advantageously avoid vibration transmission via the securing element 28, this is designed to be longer than the elastic plastic element 52. The elastic plastic element 52 is protected by the securing element 28 against external influences and damage during use of the angle grinder. Furthermore, a maximum deflection of the elastic plastic element 52 is determined by the securing element 28 from a basic position, in thrust-tilting and pulling direction. In the maximum deflection positions, the securing element 28 is tensioned and avoids further deflection of the elastic plastic element 52.

In the Fig. 7 to 12 is the embodiment in Fig. 3 an alternative handle 104 is shown. The handle 104 has a fastening part 110, which is fixedly connected via an elastic plastic element 108 with a handle portion 106. The connection between the fastening part 110 and the grip part 106 is secured by a securing element 112 formed by a screw ( Fig. 8 ).

In the manufacture of the handle 104, the fastening part 110 and the handle part 106 are first injection molded from plastic, wherein in the fastening part 110, a fastening screw Inserted 114 and molded over the form-fitting manner in the axial direction and in the direction of rotation, which in addition to an external thread 118 for attachment to a machine housing in the direction of grip part 106 has an internal thread 120. The fastening screw 114 could also be subsequently pressed into a fastening part. After encapsulation of the fastening screw 114, the fastening part 110 with the fastening screw 114 and the grip part 106 are inserted into a mold 140 in order to be materially bonded to the elastic plastic element 108 in an injection molding process ( Fig. 12 ). The mold 140 is designed such that the elastic plastic element 108 just before a circular contact surface 146 for fastening part 110 and a circular bearing surface 134 to the handle portion 106 has a non-circular cross-sectional area 116, which are each smaller than the contact surfaces 134, 146, and that has Cross-sectional area 116 each have a round core surface 122, to which radially outwardly four arcuate extensions 124, 126, 128, 130 connect ( Fig. 9 and 11 ). Also possible would be more or fewer than four arcuate extensions 124, 126, 128, 130. In a middle region, the elastic plastic element 108 has a round cross-sectional surface 136 (FIG. Fig. 10 ).

Further, a die 142 cooled via a liquid channel 148 is inserted into the mold 140, forming a recess 144 for the securing element 112, through which heat is dissipated from the inner region of the elastic plastic element 108 during manufacture. The grip part 106 is hollow on the inside and has a recess 138 in the direction of the attachment part 110, through which the core 142 protrudes and which is partially ejected with the elastic plastic element 108 is, so that an edge region of the recess 138 is engaged behind by a collar 150 of the elastic plastic element 108.

If the elastic plastic element 108 is cooled and the core 142 is removed, the securing element 112 is guided by the grip part 106 through the recess 142 made by the core 142 in the direction of the fastening part 110 through the elastic plastic element 108 and screwed into the internal thread 120 in the fastening screw 114. The securing element 112 has a screw head 132, which in the assembled state of the securing element 112 has a spacing from the grip part 106, so that the securing element 112 is mounted movably relative to the grip part 106. The screw head 132 is larger than the recesses 138 and 144, so that in case of damage of the elastic plastic member 108, the grip member 106 is captively connected to the fastening part 110. The distance between the screw head 132 and the handle portion 106 determines a maximum allowable deflection of the elastic plastic element 108. By the collar 150 direct contact between the screw head 132 and the handle portion 106 is prevented at a maximum deflection and vibration transmission largely avoided.

reference numeral

10

handle

12

handle part

14

element

16

attachment portion

18

Set screw

20

fuse element

22

fuse element

24

element

26

handle

28

fuse element

30

disc

32

disc

34

shell

36

shell

38

disc

40

disc

42

opening

44

opening

46

room

48

room

50

handle

52

element

54

cutting wheel

56

casing

58

handle

60

gearbox

62

handle

64

fuse element

66

The End

68

The End

70

attachment portion

72

handle part

74

molding

76

molding

78

opening

80

opening

82

room

84

room

86

opening

88

opening

90

insertion

92

molding

94

molding

96

opening

98

opening

100

width

102

diameter

104

handle

106

handle part

108

element

110

attachment portion

112

fuse element

114

fixing screw

116

Cross-sectional area

118

external thread

120

inner thread

122

core area

124

extension

126

extension

128

extension

130

extension

132

screw head

134

contact surface

136

Cross-sectional area

138

recess

140

Mold

142

component

144

recess

146

contact surface

148

liquid channel

150

Federation

Claims (7)

1. Portable power tool comprising at least one handle (104) which has at least one handle part (106) which is fixedly connected via at least one elastic, vibration-damping element (108) to a fastening part (110), via which the handle part (106) can be fixed to a housing (60), the connection between the handle part (106) and the fastening part (110) by the elastic element (108) being locked via at least one movable locking element (112), characterized in that the locking element (112) is formed by a rigid component, and the locking element (112) is mounted fixedly in the fastening part (110) and movably relative to the handle part (106), and the locking element (112) is fixedly connected to a fastening screw (114) arranged in the fastening part (110).
2. Portable power tool according to Claim 1, characterized in that the locking element (112) is arranged in the elastic element (108) along a centre axis.
3. Portable power tool according to Claim 1, characterized in that the locking element (112) is formed by a screw.
4. Portable power tool according to one of Claims 1 to 3, characterized in that a maximum deflection of the elastic element (108) from a basic position at least in a tilting direction and/or in a pushing direction is determined by the locking element (112).
5. Portable power tool according to one of the preceding claims, characterized in that the elastic element (108) has a non-circular cross-sectional area (116) at least just in front of a bearing surface (134, 146) relative to the fastening part (110) and/or relative to the handle part (106), said non-circular cross-sectional area (116) being smaller than the bearing surface (134, 146).
6. Method of producing a handle of a portable power tool according to one of the preceding claims, characterized in that heat is dissipated from an inner region of the elastic element (108) via at least one component (142) during the production of the elastic element (108).
7. Method according to Claim 6, characterized in that the component (142) is formed by a core which is removed after the elastic element (108) has been produced.

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