Hand-held power tool with a finger guard

Abstract

The invention relates to a hand-held power tool, in particular a rotary hammer, having a handle and a drive unit, wherein the handle has at least one gripping region and the drive unit has at least one drive motor and a transmission for driving a tool receptacle, wherein the transmission is arranged in a transmission housing which has a heat-conducting material, wherein the transmission housing at least section-wise rests on a corresponding connection interface at the gripping region, characterized in that at least one heat shield wing is arranged at the corresponding connection interface, which has a heat-insulating material and is preferably configured at least approximately perpendicular to the longitudinal extension of the gripping region, wherein the at least one heat shield wing completely covers the surface of the transmission housing which faces the at least one heat shield wing.

Description

TECHNICAL FIELD

[0001] The invention relates to a hand-held power tool, in particular a rotary hammer, having a handle and a drive unit, wherein the handle has at least one gripping region, the drive unit has at least one drive motor and a transmission for driving a tool receptacle, wherein the transmission is arranged in a transmission housing, which has a heat-conducting material, wherein the transmission housing at least section-wise rests on a corresponding connection interface at the gripping region. BACKGROUND

[0002] Such a hand-held power tool configured as a rotary hammer is known from the prior art. The rotary hammer has a drive unit with a drive motor and a transmission. Here, the transmission is arranged in a transmission housing, which has aluminum and heats up during operation of the rotary hammer. SUMMARY

[0003] The invention relates to a hand-held power tool, in particular a rotary hammer, having a handle and a drive unit, wherein the handle has at least one gripping region, the drive unit has at least one drive motor and a transmission for driving a tool receptacle, wherein the transmission is arranged in a transmission housing, which has a heat-conducting material, wherein the transmission housing at least section-wise rests on a corresponding connection interface at the gripping region. At the corresponding connection interface, at least one heat shield wing is arranged, which has a heat-insulating material and is preferably configured at least approximately perpendicular to the longitudinal extension of the gripping region. The at least one heat shield wing completely covers the surface of the transmission housing facing the at least one heat shield wing.

[0004] The invention thus makes it possible to provide a hand-held power tool in which, by means of the at least one heat shield wing, a safe and reliable application is achieved. In particular, it is possible to prevent, by means of the at least one heat shield wing, a burn of a user at the transmission housing during operation of the hand-held power tool. Furthermore, the at least one heat shield wing provides an increase in the bending stiffness of the housing, which is advantageous, for example, in the case of an impact on the hand-held power tool, for example as a result of a fall of the hand-held power tool.

[0005] Preferably, the at least one heat shield wing is configured in one piece with the housing, which forms the gripping region, wherein the drive motor is preferably arranged in the housing.

[0006] The arrangement of the at least one heat shield wing on the hand-held power tool can thus be achieved in a simple manner, wherein at the same time a stable housing can be provided.

[0007] Preferably, the at least one heat shield wing is arranged in the region of the rotational direction commutator, wherein the at least one heat shield wing is arranged at a distance of approximately 10 mm from the rotational direction commutator in the direction of the corresponding connection interface.

[0008] Thus, the user's hand, in particular the user's fingers arranged between the rotational direction commutator and the transmission housing, can be safely and reliably protected from burns in operation.

[0009] According to an embodiment, the at least one heat shield wing has a length of approximately 33 mm in the direction of the rotational axis of the tool receptacle.

[0010] Thus, a suitable heat shield can be simply and reliably provided, which protects the user's fingers of the hand-held power tool along the rotational axis of the tool receptacle.

[0011] The at least one heat shield wing preferably has a thickness of at least 1.5 mm for thermal insulation.

[0012] Thus, a light and robust heat shield wing can be provided for shielding the heat radiated by the transmission housing.

[0013] Preferably, the at least one heat shield wing has a width of approximately 10 mm perpendicular to the longitudinal extension of the grip region.

[0014] Thus, a heat shield wing can be provided in a simple manner, which protects the user's fingers of the hand-held power tool against heating of the transmission housing. Furthermore, an improved impact strength of the housing of the hand-held power tool can be achieved.

[0015] According to an embodiment, the width of the at least one heat shield wing narrows in the direction of the rotational axis of the tool receptacle towards the tool receptacle.

[0016] Thus, a safer and more reliable heat shield can be achieved, in which a breakage of the edge of the heat shield wing can be effectively avoided.

[0017] Preferably, the grip region is configured from two housing halves, which are arranged diametrically opposite each other, wherein each housing half has one heat shield wing.

[0018] Thus, a suitable housing can be provided in a simple manner.

[0019] Preferably, at least one thermal insulation element is arranged on the transmission housing.

[0020] Thus, a further heat protection measure can be simply and uncomplicatedly provided.

[0021] According to embodiments, the thermal insulation material and / or the thermal insulation element has a plastic, and / or the thermal conductive material has a light metal.

[0022] Thus, a suitable thermal insulation material can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0023] In the following description, the application is explained in detail with reference to the embodiments shown in the drawings. The drawings show:

[0024] Figure 1 Side view of a hand-held power tool with a thermal guard wing,

[0025] Figure 2 Figure 1 Perspective top view of a hand-held power tool, and

[0026] Figure 3 Figure 1 and Figure 2 Perspective front view of a hand-held power tool.

[0027] In the drawings, elements having the same or similar functions are provided with the same reference signs and are described in detail only once. DETAILED DESCRIPTION

[0028] Figure 1 An exemplary hand-held power tool 100 is shown, which illustratively has a machine housing 105 with a handle. The handle has at least one gripping region 115. According to embodiments, the hand-held power tool 100 can be connected mechanically and electrically to a battery pack 190 for the purpose of an independent supply of electrical current from the power grid, but can alternatively also be operated in connection with the power grid.

[0029] In the machine housing 105, a drive unit 110 is preferably arranged, which has at least one transmission 120 and an electric drive motor 180, which is preferably supplied with electrical current by the battery pack 190. The transmission 120 is preferably configured as a planetary gear transmission. The hand-held power tool 100 is assigned a tool receptacle 140 for receiving a plug-in tool, for example a screwdriver bit.

[0030] The drive motor 180 is preferably configured as an electronically commutated motor. The drive motor 180 is preferably configured for driving the tool receptacle 140 and thus the plug-in tool. The tool receptacle 140 is preferably rotated in operation about a rotation axis 199. The longitudinal extension 118 of the gripping region 115 preferably extends parallel to the rotation axis 199.

[0031] Preferably, the drive motor 180 can be switched on or off by means of a hand switch 195. Preferably, the hand switch 195 is arranged on the gripping region 115. Furthermore, the drive motor 180 is arranged in the housing 160. Preferably, the housing 160 is assigned the gripping region 115.

[0032] The direction of rotation of the drive motor 180 can preferably be adjusted by means of a direction-of-rotation changeover switch 196. Analogously to the hand switch 195, the direction-of-rotation changeover switch 196 is preferably also arranged on the gripping region 115. Preferably, the direction-of-rotation changeover switch 196 is configured as a press switch in which the direction of rotation of the tool-receiving portion 140 can be adjusted by means of a loading perpendicular to the longitudinal extension 118. It is pointed out, however, that the direction-of-rotation changeover switch 196 can also be configured as an electric pushbutton and / or as a rocker switch.

[0033] According to the embodiment, the transmission 120 is arranged in a transmission housing 125. Preferably, the housing 160 and the transmission housing 125 are assigned to the machine housing 105. Preferably, the housing 160 and the transmission housing 125 form the machine housing 105. Between the housing 160 and the transmission housing 125, a connection interface 128 is preferably configured. Furthermore, the transmission housing 125 at least section-wise rests on the corresponding connection interface 128 at the gripping region 115. Furthermore, the direction-of-rotation changeover switch 196 is preferably arranged in the region of the connection interface 128, but at least next to this region. Preferably, the transmission housing 125 has a thermally conductive material.

[0034] Preferably, at least one heat shield wing 170 is arranged at the corresponding connection interface 128. The at least one heat shield wing 170 preferably has a heat-insulating material. Here, the at least one heat shield wing 170 preferably completely covers the surface of the transmission housing 125 which faces the at least one heat shield wing 170.

[0035] Preferably, the heat shield wing 170 is configured at least approximately perpendicular to the longitudinal extension 118 of the gripping region 115 or along the transverse extension 119 of the gripping region 115. Figure 3 Preferably, the at least one heat shield wing 170 protrudes beyond the transmission housing 125 perpendicular to the longitudinal extension 118 or perpendicular to the rotational axis 199 of the tool-receiving portion 140.

[0036] According to the embodiment, the at least one heat shield wing 170 is configured in one piece with the housing 160. Preferably, the at least one heat shield wing 170 is arranged in the region of the direction-of-rotation changeover switch 196.

[0037] Preferably, the gripping region 115 is configured by two housing halves 112. Preferably, the two housing halves 112 are arranged diametrically opposite one another. Preferably, each housing half 112 has one heat shield wing 170.

[0038] According to an embodiment, at least one heat-insulating element 127 is arranged on the transmission housing 125. Preferably, the heat-insulating element 127 is arranged on the housing 160. Here, the heat-insulating element 127 is preferably sprayed onto the housing 160.

[0039] In the context of the present application, a heat-insulating material is understood to be a material having a comparatively small heat-conducting capacity, for example a plastic. Analogously thereto, in the context of the present application, a heat-conducting material is understood to be a material having a comparatively high heat-conducting capacity, for example a light metal. Preferably, the heat-insulating material and / or the heat-insulating element 127 has a plastic. The heat-conducting material can have a light metal. Preferably, the heat-conducting material has aluminum and / or magnesium.

[0040] Exemplarily, the hand-held power tool 100 is configured as a rotary impact driver having an impact mechanism 150. The impact mechanism 150 is preferably provided with a protective cover 155. According to an embodiment, the protective cover 155 has a heat-insulating material. It is pointed out, however, that the present application is not limited to a rotary impact driver, but can be applied generally in different hand-held power tools having an impact mechanism 150 and having a housing comprising a heat-conducting material, without an impact mechanism.

[0041] Figure 2 The hand-held power tool 100 is shown Figure 1 and the at least one heat shield wing 170 is explained. Here, the at least one heat shield wing 170 is arranged illustratively at a distance A from the rotational direction reversing switch 196 in the direction of the corresponding connection interface 128. Preferably, the distance A is formed such that a finger, in particular an index finger, of a user of the hand-held power tool 100 can be arranged between the heat shield wing 170 and the rotational direction reversing switch 196. Preferably, the distance A is approximately 10 mm.

[0042] Furthermore, the at least one heat shield wing 170 has a length L illustratively in the direction of the rotational axis 199 of the tool receptacle 140 or along the longitudinal extension 118 of the gripping region 115. The length L is preferably formed such that a finger, in particular an index finger, of a user of the hand-held power tool 100 is shielded by the heat shield wing 170 with respect to the transmission housing 125 at the connection interface 128. Preferably, the length L has an approximate value of 33 mm.

[0043] Furthermore, the at least one heat shield wing 170 has a thickness D, which is explained by way of example for thermal decoupling. Preferably, the thickness D has at least 1.5 mm. Preferably, the heat shield wing 170 has a thickness D of 3 mm.

[0044] Likewise, the at least one heat shield wing 170 has a width B, which is explained by way of example perpendicular to the longitudinal extension 118 of the gripping region 115 or else along the transverse extension of the gripping region 115 (in the drawing: 399). Preferably, the width B is formed in such a way that direct contact of the fingers, in particular the index finger, of a user of the hand-held power tool 100 with the transmission housing 125 perpendicular to the longitudinal extension 118 of the gripping region 115 is prevented by the heat shield wing 170. Preferably, the width B has approximately 10 mm. Figure 3

[0045] According to the embodiment, the width B of the at least one heat shield wing 170 narrows in the direction of the rotational axis 199 of the tool receptacle 140 towards the tool receptacle 140. Here, the narrowing of the width B can be implemented arbitrarily, for example, in a ramp shape, an arc shape and / or a stepped shape. The narrowing preferably has an angle of less than 90°, preferably 45°, thereby achieving an increase in the stability of the housing 160, in particular of the heat shield wing 170. Better stability, in particular in the event of a fall of the hand-held power tool 100, is advantageous for preventing damage to the housing 160 or the heat shield wing 170.

[0046] However, the at least one heat shield wing 170 preferably has a width B which is formed at least in such a way that the gripping region 115 is completely thermally decoupled from the transmission housing 125 in the region of the connection interface 128 by the heat shield wing 170. That is, the at least one heat shield wing 170, owing to its width B, completely overhangs the transmission housing 125 along the connection interface 128. Furthermore, the at least one heat shield wing 170 preferably terminates flush, in particular without a gap, on the transmission housing 125.

[0047] Furthermore, the at least one heat shield wing 170 has a thickness D, which is explained by way of example for thermal decoupling. Preferably, the thickness D has at least 1.5 mm. Preferably, the heat shield wing 170 has a thickness D of 3 mm. Figure 2 Figure 1 The at least one heat shield element 127 is explained in the following. Preferably, the at least one heat shield element 127 has a length of preferably 25 mm in the direction of the rotational axis 199 of the tool receptacle 140 or else along the longitudinal extension 118 of the gripping region 115. Furthermore, the heat shield element 127 has a width of preferably approximately 30 mm at least approximately perpendicular to the longitudinal extension 118 of the gripping region 115. Preferably, the at least one heat shield element 127 has a thickness d of at least 1.5 mm, preferably 3.5 mm.

[0048] ​​As described above, the thermal insulation element 127 is arranged on the housing 160, in particular sprayed onto the housing. Explanatorily, the thermal insulation element 127 is positioned on the transmission housing 125 in the longitudinal extension 118 of the gripping region 115. Here, the thermal insulation element 127 is positioned between the two screw flanges 211, 212 of the transmission housing 125. Here, the at least one thermal insulation element 127 can be configured as a heat shield when the hand-held power tool 100 is loaded on the end opposite the tool receptacle 140. Furthermore, a plurality of thermal insulation elements 127 can also be arranged in the region of the transmission housing 125.

[0049] The screw flanges 211, 212 of the transmission housing 125 serve to receive bolt elements for connecting the transmission housing 125 with the housing 160. Preferably, the at least one heat shield wing 170 is arranged on the screw flange 212. Preferably, the screw flange 212 is arranged in the region of the rotational direction reversing switch 196.

[0050] It is pointed out that the values explained above only have exemplary character. Thus, the values for the length L, the width B, the thickness D and / or the distance A of the heat shield wing 170 can also be greater or smaller predefined. Furthermore, the at least one thermal insulation element 127 can also have dimensions different from those described above.

[0051] Figure 3 It is shown Figure 1 and Figure 2 a hand-held power tool 100 having a housing 160 and a transmission housing 125. As described above, according to the embodiment, the housing 160 or the gripping region 115 has two housing halves 112 which are arranged diametrically opposite one another. Explanatorily, each housing half 112 has one heat shield wing 170. Here, as described above, the heat shield wing 170 is configured at least approximately perpendicular to the longitudinal extension 118 of the gripping region 115 or at least approximately along the transverse extension 399 of the gripping region 115.

[0052] The heat shield wing 170 does not have to be arranged perpendicular to the longitudinal extension 118, but can also be oriented at a predefined angle with respect to the longitudinal extension 118. Preferably, the predefined angle is greater than 100° and less than or equal to 120°. Thereby, the stability of the housing 160, in particular of the heat shield wing 170, can be increased. Furthermore, explanatorily, two heat shield wings 170 can also be configured differently in size and / or at different angles with respect to the longitudinal extension 118.

Claims

1. Hand-held power tool (100) having a handle and a drive unit (110), wherein The handle has at least one gripping region (115), the drive unit has at least one drive motor (180) and a transmission (120) for driving a tool receptacle (140), wherein the transmission (120) is arranged in a transmission housing (125) which has a heat-conducting material, wherein the transmission housing (125) at least section-wise bears against a corresponding connection interface (128) at the gripping region (115), characterized in that at least one heat shield wing (170) is arranged at the corresponding connection interface (128), which has a heat-insulating material and is configured perpendicular to a longitudinal extent (118) of the gripping region (115), wherein the at least one heat shield wing (170) completely covers a surface of the transmission housing (125) which faces the at least one heat shield wing (170).

2. The hand-held power tool as claimed in claim 1, characterized in that The hand-held power tool is a rotary hammer drill.

3. The hand-held power tool as claimed in claim 1, characterized in that The at least one heat shield wing (170) is configured in one piece with a housing (160) which forms the gripping region (115).

4. The hand-held power tool according to claim 3, characterized in that The drive motor (180) is arranged in the housing (160).

5. The hand-held power tool according to any one of claims 1 to 4, characterized by, The at least one heat shield wing (170) is arranged in the region of a rotational direction commutator (196), wherein the at least one heat shield wing (170) is arranged at a distance (A) of 10 mm from the rotational direction commutator (196) in the direction of the corresponding connection interface (128).

6. The hand-held power tool according to any one of claims 1 to 4, characterized by The at least one heat shield wing (170) has a length (L) of 33 mm in the direction of the rotational axis (199) of the tool receptacle (140).

7. The hand-held power tool according to any one of claims 1 to 4, characterized by The at least one heat shield wing (170) has a thickness (D) of at least 1.5 mm for thermal insulation.

8. The hand-held power tool according to any one of claims 1 to 4, characterized by, The at least one heat shield wing (170) has a width (B) of 10 mm perpendicular to the longitudinal extent (118) of the gripping region (115).

9. The hand-held power tool as claimed in claim 8, characterized in that The width (B) of the at least one heat shield wing (170) narrows in the direction of the rotational axis (199) of the tool receptacle (140) towards the tool receptacle (140).

10. The hand-held power tool according to any one of claims 1 to 4, characterized by, The gripping region (115) is configured from two housing halves (112) which are arranged diametrically opposite one another, wherein each housing half (112) has one heat shield wing (170).

11. The hand-held power tool according to any one of claims 1 to 4, characterized by At least one heat-insulating element (127) is arranged at the transmission housing (125).

12. The hand-held power tool according to claim 11, characterized by The heat-insulating material and / or the heat-insulating element (127) has a plastic, and / or the heat-conducting material has a light metal.

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