Hand-Held Power Tool with a Cooling Unit

20170361416 · 2017-12-21

    Inventors

    Cpc classification

    International classification

    Abstract

    A hand-held power tool includes a housing, a motor, a cooling unit, and a plurality of electronics. The housing includes a first housing part and an air intake opening. The motor is assigned to a drive train of the hand-held power tool. The cooling unit is configured to cool the motor. The plurality of electronics is located in the housing. The first housing part includes at least one air channel that is integral with the first housing part. The air intake opening is configured to conduct a cooling air flow directly to the motor via the at least one air channel.

    Claims

    1. A hand-held power tool, comprising: a housing including a first housing part and an air intake opening; a motor assigned to a drive train of the hand-held power tool and located in the housing; a cooling unit located in the housing and configured to cool the motor; and a plurality of electronics located in the housing, wherein the first housing part includes at least one first air channel that is integral with the first housing part, and wherein the air intake opening is configured to conduct a cooling air flow directly to the motor via the at least one first air channel.

    2. The hand-held power tool according to claim 1, wherein the at least one first air channel includes an air inlet opening and an air outlet opening, and is configured in a closed manner.

    3. The hand-held power tool according to claim 1, wherein: the housing includes at least one second housing part having at least one second air channel; the first housing part further includes a third air channel; and the at least one first air channel, the at least one second air channel, and the third air channel are arranged in a circumferential direction of the housing.

    4. The hand-held power tool according to claim 3, wherein the at least one first air channel of the first housing part and the at least one second air channel of the second housing part are arranged so as to provide an anti-rotation device of the first and second housing parts with respect to each other.

    5. The hand-held power tool according to claim 3, wherein at least one of the first housing part and the at least one second housing part is a socketed cover including at least one fourth air channel.

    6. The hand-held power tool according to claim 1, wherein the air intake opening is located on at least one of an end-face end of the housing and a side of the housing.

    7. The hand-held power tool according to claim 1, wherein: the at least one first air channel includes a recess; and a cooling body of the plurality of electronics is located in the recess, such that the cooling body forms at least a portion of at least one wall of the at least one first air channel.

    8. The hand-held power tool according to claim 1, wherein at least a portion of a cooling body of the plurality of electronics at least partially defines the at least one first air channel.

    9. The hand-held power tool according to claim 5, wherein: the plurality of electronics is arranged on a carrier component; and the carrier component includes at least one fifth air channel.

    10. The hand-held power tool according to claim 9, wherein the carrier component is a cooling body.

    11. The hand-held power tool according to claim 1, wherein the hand-held power tool is an angle-grinding machine.

    12. The hand-held power tool according to claim 1, wherein the housing is a motor housing.

    13. The hand-held power tool according to claim 3, wherein the at least one second housing part is a handle housing.

    14. The hand-held power tool according to claim 10, wherein the cooling body includes a heat-conducting material.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0026] Further advantages are produced from the following description of the drawings. Exemplary embodiments of the disclosure are shown in the drawings. The drawing, the description and the claims include numerous features in combination. The person skilled in the art will also look expediently at the features individually and form them into sensible further combinations. The drawings are as follows:

    [0027] FIG. 1a: shows a perspective view of a hand-held power tool with air channels,

    [0028] FIG. 1b: shows a perspective view of a hand-held power tool according to FIG. 1a without a socketed cover,

    [0029] FIG. 1c: shows a perspective view of a hand-held power tool according to FIG. 1b without a handle housing,

    [0030] FIG. 1d: shows a perspective part view of the handle housing of the hand-held power tool according to FIG. 1a,

    [0031] FIG. 1e: shows a further perspective part view of the handle housing of the hand-held power tool according to FIG. 1a,

    [0032] FIG. 1d: shows a perspective partial section of the handle housing of the hand-held power tool according to FIG. 1a,

    [0033] FIG. 1e: shows a perspective view of the handle housing of the hand-held power tool according to FIG. 1d,

    [0034] FIG. 1f: shows a cross section through the air channels of the hand-held power tool according to FIGS. 1a-1e,

    [0035] FIG. 2a: shows a perspective view of a socketed cover with air channels,

    [0036] FIG. 2b: shows a perspective view of a socketed cover with air channels,

    [0037] FIG. 3: shows a cross section through a hand-held power tool with an alternative embodiment of air channels,

    [0038] FIG. 4a: shows a perspective view of a hand-held power tool,

    [0039] FIG. 4b: shows a perspective view of a hand-held power tool,

    [0040] FIG. 5: shows a perspective view of a hand-held power tool with an alternative arrangement of the air intake openings,

    [0041] FIG. 6a: shows a perspective view of a hand-held power tool with an alternative embodiment of the air channels,

    [0042] FIG. 6b: shows a perspective view of a hand-held power tool with an alternative embodiment of the air channels,

    [0043] FIG. 7a: shows a perspective view of a hand-held power tool with a further alternative embodiment of the air channels,

    [0044] FIG. 7b: shows a perspective view of a hand-held power tool with a further alternative embodiment of the air channels,

    [0045] FIG. 8a: shows a perspective view of a hand-held power tool with a third alternative embodiment of the air channels,

    [0046] FIG. 8b: shows a perspective view of a hand-held power tool with a third alternative embodiment of the air channels,

    [0047] FIG. 9a: shows a perspective view of a hand-held power tool with a fourth alternative embodiment of the air channels,

    [0048] FIG. 9b: shows a perspective view of a hand-held power tool with a fourth alternative embodiment of the air channels,

    [0049] FIG. 10a: shows a perspective view of a carrier component with air channels,

    [0050] FIG. 10b: shows a perspective view of a carrier component with air channels.

    DETAILED DESCRIPTION

    [0051] FIGS. 1a to 1e show a perspective view of a hand-held power tool 10 with air channels 100, 200. FIG. 1b shows a perspective view of a hand-held power tool 10 according to FIG. 1a without a socketed cover 50 and FIG. 1c shows a perspective view of a hand-held power tool 10 according to FIG. 1b without a handle housing 40. The hand-held power tool 10 is realized, as an example, as an angle-grinding machine. The hand-held power tool 10 comprises a housing 12 which includes a gear head 20, a motor housing 30, a handle housing 40 and a socketed cover 50. The gear head 20 can be produced from a metal and is fastened on the motor housing 30 by way of screws. An additional handle is mountable, as an example, on the gear head 20 by means of a receiving means 21. A receiving flange (not shown), on which a protective cover is rotatably fastenable, is arranged on the bottom surface of the gear head 20. The receiving flange comprises a central opening, through which an output spindle 26 is guided. The output spindle 26 is realized so as to be rotatably connectable or rather couplable to or with an insertion tool (not shown) of the hand-held power tool 10, for example a cutting disk.

    [0052] The motor housing 30 includes, as an example, two portions. The first portion of the motor housing 30 is realized in the manner of a hollow cylinder. In particular, an electric motor 32 is arranged in the first portion of the motor housing 30. The first portion of the motor housing 30 is loosely connected to the gear head 20 on a first connecting region 31. A fan element (not shown), which is realized for the purpose of generating a cooling air flow 5 for cooling the electric motor 32, is arranged on the motor-housing-side in the first connecting region 31 of the motor housing 30. The electric motor 32 includes a motor shaft which is coupled with the output spindle 26 by means of a crown wheel. The motor shaft extends along the axial axis 1 of the hand-held power tool 10. In particular, the rotational axis of the motor shaft corresponds to the axial axis 1 of the hand-held power tool 10. In the second connecting region 39 of the motor housing 30, the outside contour of the motor housing 30 merges into the outside contour of the handle housing 40. The handle housing 40 is realized in a pot-shaped manner. The handle housing 40 comprises air intake openings 110, through which the cooling air is able to enter into the housing 12 of the hand-held power tool 10, on the end-face end of the hand-held power tool 10. Another socketed cover 50, which comprises air intake openings 112, 114 and a screw receiving opening 116, is arranged in addition on the end-face end of the hand-held power tool 10. The handle housing 40 can be slid open by means of the second portion of the motor housing 30. The socketed cover 50 is fitted onto the handle housing 40. The handle housing 40 is connected to the motor housing 30 and to the socketed cover 50 by means of a screw 118, the counter thread for the screw 118 being arranged in the motor housing 30. In the connected state, a cable support sleeve 52, which is realized for the purpose of conducting a mains cable 54 into the hand-held power tool, is mounted between the handle housing 40 and the socketed cover 50. The second portion of the motor housing 30 is realized as a continuation which is encased by the handle housing 40. The second portion of the motor housing 30 is provided for the bearing arrangement or receiving of hand-held power tool components, in particular, the electronics 42. The electronics 42 include, as an example, a setting wheel 46 which is provided for adjusting the speed of the insertion tool, at least one electric contact element 48 which is provided for the electric connection between a switching element 49 and the drive train of the hand-held power tool 10, a shift linkage 45, a push button of the switching element 49 being actuatable via the shift linkage 45 when the operating switch 41 is actuated, and at least one mains connection 47 which is realized for the purpose of connecting the mains cable 54 to the electronics 42 in an electrical manner. The electronics 42 are arranged at least in part in a carrier component 44 which is realized so as to be detachably fastenable on the motor housing 30.

    [0053] The hand-held power tool 10 is shown in the form of a mains-operated hand-held power tool which comprises the mains cable 54 for the power supply on the rear end 51 of the hand-held power tool 10. However, it is also conceivable for the power supply to be realized by means of a rechargeable battery pack, the rechargeable battery pack being connectable mechanically and electrically to the hand-held power tool via a rechargeable battery pack interface. A rechargeable battery pack is to be understood, in this case, as one or several battery cells which are connected together and are arranged in a housing. The housing of the rechargeable battery pack, in this case, comprises a rechargeable battery pack interface on its outside surface.

    [0054] The air intakes 110, 112, 114 of the hand-held power tool 10 are distributed, as an example, over two housing parts 40, 50. The air intakes 110, which are arranged, in particular, in the vicinity of the socket receiving means, are realized, as an example, as air inlet openings 102 of the air channels 200 of the handle housing 40. In an advantageous manner, the cooling air flow 5 can be conducted directly into an air channel 200. The handle housing 40 and the air channel 200 which are assigned to the handle housing 40 are shown in perspective in FIG. 1d and FIG. 1e. The air channels 200 are realized in a closed and integral manner with the handle housing 40. The cooling air flow 5 enters into the air channel 200 via air inlet openings 102 and leaves the air channel 200 via air outlet openings 104. The air outlet openings 104 are advantageously arranged in such a manner that the cooling air flow 5 is conducted directly to the motor without the cooling air flow 5 acting upon essential components of the electronics 42, such as the switching element 49 or the mains connection 47. In addition, the cooling air flow 5 can also enter into the hand-held power tool 10 through air intake openings 112 which are assigned, as an example, to the socketed cover 50 and is then conducted to air inlet openings 102 of the air channel 200. The cooling air flow 5 is conducted via the air intake openings 112 to air inlet openings 102 of air channels 100, 200 which are assigned both to the handle housing 40 and to the motor housing 30 (can be seen in FIG. 1c). FIG. 1c also shows that the air channels 100, 200 extend substantially parallel to the axial axis 1 of the hand-held power tool 10 and in a substantially linear manner.

    [0055] FIG. 1f shows a cross section through the air channels 100, 200 of the hand-held power tool 10 according to FIGS. 1a-1e. The housing 12 of the hand-held power tool 10 comprises a total of seven air channels 100, 200 which are arranged in the circumferential direction of the hand-held power tool 10 in such a manner that the cooling air is conducted past the side of components of the electronics 42 such as, for example, the shift linkage 45, the switching element 49 and the carrier component 44. The air channels 100, 200 of the various housing parts 30, 40 are arranged, in this case, at least in part along the circumferential direction in such a manner that a wall of an air channel 100 of a first housing part abuts against the wall of an air channel 200 of a second housing part and, as a result, the two housing parts 30, 40 are prevented from rotating about the axial axis 1.

    [0056] FIG. 2a and FIG. 2b show a perspective view of an alternative embodiment of the socketed cover 50a. The socketed cover 50a comprises air intake openings 112a which are realized as air inlet openings 102a for the air channels 100a which are integrally molded on the inside surface of the socketed cover 50a. It is conceivable for the air channels 100a of the socketed cover 50a to replace the air channels 100, 200 of the other housing parts 30, 40 at least in part.

    [0057] It is also conceivable, as shown in FIG. 3, for at least one air channel 200c not to be realized in an integral manner. It is, for example, conceivable for an air channel 100c of the handle housing 40c to be realized only closed in part and, in particular, to comprise a recess 101c in the wall along the longitudinal extension of the air channel 200c. In particular, the wall of an integrally realized air channel 100 is arranged in such a manner in the recess of the partially close air channel 200c that the cooling air is not able to leave the partially closed air channel 200c via the recess 101c. As a result, double walls can be avoided, as a result of which savings in installation space and material costs are able to be made.

    [0058] As shown in FIG. 4a and FIG. 4b in a perspective view, the hand-held power tool 10 can comprise a separate cooling channel 120 for cooling the electronics 42, which channel extends substantially parallel to the air channels 100. As a result of separating the airflow in the housing 12 of the hand-held power tool 10 into air channels 100 which are provided for cooling the motor and into cooling channels 120 which are provided for cooling the electronics, a particularly efficient distribution of the performance of the cooling inside the hand-held power tool 10 can be realized. The cooling air in the cooling channel 120 acts advantageously upon a cooling body 122 of the electronics 42 which dissipates the waste heat of the electronics 42 in an efficient manner.

    [0059] FIG. 5 shows a further alternative design of the housing 12d of the hand-held power tool 10. The housing 12d advantageously comprises lateral air intake openings 116d which are connectable to air inlet openings of air channels (not shown). As a result, air intake openings 116d can be realized in an advantageous manner laterally or rather transversely with respect to the axial axis 1 of the hand-held power tool 10. As an example, the socketed cover 50d is arranged both on the end face of and on the side of the handle housing 40d and comprises both end-face air intake openings 112d, 114d and lateral air intake openings 116d.

    [0060] FIG. 6a and FIG. 6b shows an alternative embodiment of a motor housing 30e with closed air channels 100e. The air channels 100e of the motor housing 30e comprise along their longitudinal extension in each case a recess 101e, into which the cooling body 122e of the electronics 42 can be arranged in part. In particular, two wings 123e of the cooling body replace the walls of the air channels 100e in the recesses 101e in such a manner that the air channel 100e continues to be realized in a substantially closed manner apart from the gaps which are to be traced back to the material transitions. The material transition in FIG. 6a and FIG. 6b is formed, as an example, from a transition from the handle housing 40e, which is realized from a hard elastic plastics material, to the cooling body 122e which is realized from a metal. In an advantageous manner, efficient passive cooling of the electronics 42 can be realized as a result of the part arrangement of the cooling body 122e in the wall of the air channel 100e. In an advantageous manner, no separate cooling channel 120 is provided for the electronics 42 in said embodiment, as a result of which the performance of the cooling of the motor is raised. It is consequently conceivable for the electronics 42 to be realized so as to be insulated from the cooling air as a result of the connection between the cooling body 122e and the air channels 100e.

    [0061] As an alternative to this, the air channel 100f can comprise a recess 101f, through which the cooling body 122f of the electronics 42 projects at least in part into the air channel 100f, as shown in FIG. 7a and FIG. 7b. In an advantageous manner, a wing 123f of the cooling body 122f projects in such a manner into the air channel 100f that it abuts tightly against the wall of the air channel 100f. In particular, the top surface of the side surface 125f of the wing 123f of the cooling body 122f inside the air channel 100f extends substantially parallel to the wall of the air channel 100f against which the wing 123f abuts. In an advantageous manner, as a result of said arrangement the cooling air in the interior of the air channel 100f is only swirled minimally by the wing 123f of the cooling body 122f. In an advantageous manner, in this case, only one side surface 125f of the wing 123f is acted upon by the cooling air.

    [0062] To increase the performance of the cooling of the electronics, the recess 101g can also be arranged in such a manner in the wall of the air channel 100g that the wing 123g of the cooling body 122g projects into the air channel 100g at a spacing from the wall of the air channel 100g, as shown in FIG. 8a and FIG. 8b. In an advantageous manner, two oppositely situated side surfaces 125g, 126g are acted upon by the cooling air as a result. In order to minimize the turbulence occurring as a result, the side surfaces of the wing 123g are arranged along the direction of flow of the cooling air.

    [0063] FIG. 9a and FIG. 9b show a housing 12 with a further alternative embodiment of the air channel 100h. The air channel 100h is realized integrally with the motor housing 30h, in particular in an interrupted manner. A channel-shaped wing 123h of the cooling body 122h is arranged in the interruption 106h of the air channels. In an advantageous manner, the wing 123h of the cooling body is formed in such a manner that the wing forms a channel with an inlet opening 125h and an outlet opening 127h, the cross section of which corresponds substantially to the cross section of the air channel 100h. The channel-shaped wing 123h is advantageously arranged in such a manner in the interruption 106h that the air channel 100f continues to be realized in a substantially closed manner. In particular, the wall of the air channel 100h is continued in the interruption 106h by the wing 123h of the cooling body unit 120h.

    [0064] In a further alternative embodiment, the air channels 100i can be realized integrally with the carrier component 44i (shown in FIG. 10a and FIG. 10b). The setting wheel 46, the mains connections 47 and an electronic element 43 are arranged, as an example, on the carrier component 44i. In an advantageous manner, cooling air is conducted to the air inlet openings 102i of the air channels 100i via air intake openings which are arranged on the end face of the housing of the hand-held power tool (not shown). In this case, the air intake openings can be arranged in a housing part such as, for example, the handle housing 40 or the socketed cover 50, or realized as air inlet openings 102i of the air channels 100i. The carrier component 44i is realized from an insulating material. An insulating material is to be understood, in particular, as a plastics material with a resistance of at least 10.sup.12Ω. In an advantageous manner, the air channels 100i, in particular the carrier component 44i, are realized from a heat-conducting material. A heat-conducting material is to be understood, in this case, in particular, as a plastics material which comprises heat conductivity of at least 0.3 W/mK. In an advantageous manner, the electronics 42 can be cooled as a result of a heat-conducting carrier component 44i with integrally realized air channels 100i by means of the cooling air which flows through the air channels 100i, without the electronics 42 comprising a separate cooling body unit. To increase the performance of the cooling of the electronics 42, the air channels 100i can comprise ribs 127i. The ribs 127i are realized integrally with the carrier component 44i and extend along the longitudinal extension of the air channels 100i. The ribs 127i provide an additional top surface inside the air channels 100i, via which the waste heat of the electronics 42 is able to dissipate. It is conceivable to arrange further ribs 127i inside the air channel 100i in order to increase the performance of the cooling further.