Hand-held power tool, fanless storage battery

A hand-held power tool, in particular a hammer drill or a combination hammer, is disclosed. The hand-held power tool includes a tool housing which has a receiving recess designed to replaceably receive a storage battery or a power supply unit. The hand-held power tool has an electric drive motor with a cooling fan. The tool housing has a first vent portion which is located in the receiving recess and through which a volume flow generated by the cooling fan can be guided.

This application claims the priority of International Application No. PCT/EP2015/078006, filed Nov. 30, 2015, and European Patent Document No. 14195558.3, filed Dec. 1, 2014, the disclosures of which are expressly incorporated by reference herein.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates to a hand-held power tool, in particular a hammer drill or combination hammer comprising a tool housing which has a receiving recess designed to replaceably receive a storage battery or power supply unit, with the hand-held power tool containing an electric drive motor having a cooling fan.

The electric drive motor of the hand-held power tool, which generates heat during operation, can be cooled by the cooling fan.

Hand-held power tools, in particular a hammer drill or combination hammer, can be selectively supplied with electric power by a storage battery or a power supply unit if they are connected to the hand-held power tools. For this purpose, the power supply unit has a power cable which establishes a connection to the mains power supply (also referred to as a power outlet).

The present invention also relates to a fanless storage battery for a hand-held power tool, with the fanless storage battery being designed to be replaceably received inside a receiving recess of a hand-held power tool.

The present invention further relates to a tool system comprising a hand-held power tool and a fanless storage battery.

The object of the present invention is to provide a hand-held power tool, a storage battery and a tool system with improved cooling properties.

With regard to the hand-held power tool, the object is achieved by the tool housing having a first vent portion which is located in the receiving recess and through which a volume flow generated by the cooling fan can be guided.

According to an advantageous embodiment of the present invention, the first vent portion can be provided such that the volume flow can be guided through the storage battery received in the receiving recess with a partial open surface. The storage battery can be hereby efficiently cooled by means of the cooler of the hand-held power tool without a separate cooler having to be provided in the storage battery.

In order to provide a direct cooling flow for the hand-held power tool and in particular for the drive motor which ensures efficient cooling, it may be advantageous for the tool housing to have a second vent portion that is different from the first vent portion and is located outside of the receiving recess and through which the volume flow generated by the cooling fan can be at least partially guided.

According to a further advantageous embodiment, it may be possible for the hand-held power tool to have a flow control means which is designed to distribute a volume flow generated by the cooling fan between the first vent portion and the second vent portion. The volume flow of the cooling fan can be hereby controlled such that both the storage battery and the drive motor are cooled.

Since the temperature of the storage battery can rise to a critical value during its use in the hand-held power tool, whereby the performance or even the functionality of the storage battery is negatively affected, it may be advantageous for the flow control means to be regulatable depending on a temperature measured in the storage battery.

According to a preferred embodiment of the present invention, it may be advantageous for the flow control means to be regulatable depending on at least one temperature measured in the hand-held power tool. The hand-held power tool and in particular the drive motor can be hereby effectively and targetedly cooled with the aid of the volume flow of the cooling fan when they have reached a critical temperature.

In order to allow the entire volume flow of the cooling fans to flow either only through the storage battery or only through the hand-held power tool in order to therefore reach maximum cooling either of the storage battery or the hand-held power tool, it may be advantageous for the flow control means to be designed as a change-over flap that can be actuated by a control device, the change-over flap closing the first vent portion in a first switch position and closing the second vent portion in a second switch position.

According to an advantageous embodiment of the present invention, the change-over flap can be set in at least one switch position between the first switch position and the second switch position whereby a higher proportion of volume flow is allocated either through the first vent portion or the second vent portion. Either stronger cooling of the storage battery and weaker cooling of the hand-held power tool or else stronger cooling of the hand-held power tool and weaker cooling of the storage battery can be hereby achieved. Furthermore, identically strong cooling of the storage battery and the hand-held power tool is also simultaneously possible.

It has been found to be advantageous when the first vent portion and the second vent portion are associated with vents that are different to each other. Alternatively, the first vent portion and the second vent portion can belong to the same vent. The first vent portion and the second vent portion are preferably located substantially perpendicular to each other.

With regard to the fanless storage battery for a hand-held power tool that has a receiving recess designed to replaceably receive the storage battery and an electric drive motor having a cooling fan, the present object is achieved by the fanless storage battery having an inner ventilation channel that is open to the environment via which the fanless storage battery can be force-cooled by means of a volume flow generated by the cooling fan of the hand-held power tool when the fanless storage battery is received in the receiving recess of the hand-held power tool.

With regard to the tool system, the present object is achieved by a tool system which has a previously described hand-held power tool and a previously described fanless storage battery.

Further advantages will emerge from the following description of the figures. Different exemplary embodiments of the present invention are represented in the figures. The figures, the description and the claims contain numerous features in combination. The person skilled in the art will also expediently consider the features individually and combine them to form appropriate further combinations.

The same and similar components are numbered with the same reference numerals.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1shows a fanless storage battery200according to the invention. The storage battery200is designed to be replaceably received without using a tool in a receiving recess80not shown (seeFIG. 2), with a representation of fastening means being dispensed with in this case.

The storage battery200contains an inner ventilation channel210via which the storage battery200is force-cooled. The inner ventilation channel210runs between a front vent211and a rear vent212which are located on opposing front sides of the storage battery200. The storage battery200as well as the cells and electronics, which are located inside the storage battery200, can be cooled with the aid of the inner ventilation channel210or a ventilation flow guided through the ventilation channel210. The cells and the electronics of the storage battery200are not shown in the figures. The storage battery200has an open surface through the front vent211and rear vent212.

A first embodiment of a hand-held power tool100according to the invention in the form of a hammer drill is represented inFIG. 2. The hand-held power tool100in this case contains substantially one tool housing90which has a receiving recess80designed to replaceably receive a storage battery200. The receiving recess80serves to replaceably receive the storage battery200. An electric drive motor70having a cooling fan60as well as a control device30are further positioned in the tool housing90. The drive motor70serves to generate a torque which is transferred via a gear mechanism to a tool. Neither the gear mechanism nor the tool is represented in the figures. The control device30serves to control and regulate the drive motor70, a change-over flap20as well as a first and second slat arrangement10a,10b.The control device30is for this purpose connected via lines that are not shown to the drive motor70, the change-over flap20and the slat arrangements10a,10b.The change-over flap20as well as the first and second slat arrangement10a,10bare described below in detail.

As is also visible inFIG. 2, the tool housing90contains a first vent portion40. The first vent portion40substantially constitutes one opening into the tool housing90through which the cooling fan60can suction cooling air from the environment U. The first vent portion40is in this case arranged towards the receiving recess80such that the front vent211of the storage battery200rests on the vent portion40when the storage battery200is connected to the hand-held power tool100in the receiving recess80. A volume flow, which is suctioned by the cooling fan60inside the hand-held power tool100from the environment U, can flow through the storage battery200with the aid of the previously described inner ventilation channel210in order to cool the storage battery. The volume flow V in this case enters through the rear vent212into the storage battery200, crosses the ventilation channel210, enters through the front vent211from the storage battery200and enters through the first vent portion40into the tool housing90. The storage battery200is thus cooled by the volume flow V of the cooling fan60.

FIG. 3shows a second embodiment of the hand-held power tool100according to the invention which is substantially identical to the first embodiment. Unlike the first embodiment, the tool housing90contains a second vent portion50in addition to the first vent portion40. As is visible inFIG. 3, the first vent portion40and the second vent portion50are associated with vents that are different to each other which are located perpendicular to each other on the tool housing90. The second vent portion50, like the first vent portion40, constitutes an opening into the tool housing90through which a volume flow V generated by the cooling fan60can be suctioned from the environment U into the inside of the hand-held power tool100. In this case, a first volume flow V1is suctioned through the first vent portion40and a second volume flow V2is suctioned through the second vent portion50. According to the second embodiment, in relation to the first embodiment, separate cooling in the form of the volume flow V2is provided for the drive motor70through the second vent portion50which is not guided through the storage battery200and consequently is also not heated by the storage battery200.

FIGS. 4, 5 and 6show the hand-held power tool100according to the invention according to a third embodiment. The hand-held power tool100according to the third embodiment is substantially identical to the hand-held power tool100according to the second embodiment. Unlike the hand-held power tool100according to the second embodiment, the hand-held power tool100according to the third embodiment, also contains a flow control means which is configured to distribute the volume flow V generated by the cooling fan60between the first vent portion40and the second vent portion50. As represented inFIGS. 4, 5 and 6, the flow control means is configured in the form of a change-over flap20. The change-over flap20is in this case located in the tool housing90such that it can be pivoted continuously and reversibly between a first switch position20A and a second switch position20B. The change-over flap20can also be set in a middle switch position20M between the first switch position20A and the second switch position20B.

FIG. 4shows the change-over flap20in the first switch position20A in which the change-over flap20completely closes the second vent portion50such that no cooling air can be suctioned from the environment U through the second vent portion50into the inside of the tool housing90. At the same time, the first vent portion40is completely closed so that the volume flow V is suctioned only through the first vent portion40into the inside of the tool housing90. The storage battery200thereby experiences maximum cooling. The change-over flap20is horizontal for this purpose.

FIG. 5shows the change-over flap20in the middle switch position20M in which the first vent portion40and the second vent portion50are partially open. In the middle switch position20M cooling air can flow both in the form of a volume flow V1through the first vent portion40and in the form of a volume flow V2through the second vent portion50.

FIG. 6shows the change-over flap20in the second switch position20B in which the change-over flap20completely closes the first vent portion40such that no cooling air can be suctioned from the environment U through the first vent portion40into the inside of the tool housing90. At the same time, the second vent portion50is completely open such that the volume flow V is suctioned only through the second vent portion50into the inside of the tool housing90. The storage battery200thereby experiences no cooling in the form of cooling air flowing through the inner ventilation channel210. The drive motor70, in contrast, experiences maximum cooling.

The switch position of the change-over flap20is controlled and regulated by means of the control device30. The control device30is connected to a first temperature sensor and a second temperature sensor. The first temperature sensor is in this case positioned such that it measures the temperature of the storage battery200. The second temperature sensor is, in contrast, positioned such that it measures the temperature of the drive motor. The temperature data measured by the respective temperature sensors are sent to the control device30. The control device30can determine whether an excessively high and therefore critical temperature has been reached for the storage battery200and/or the drive motor70by way of a comparison with reference temperature values stored in the control device30. If the measured temperature value indicates a storage battery200that is too warm, the control device30sends a corresponding signal to the change-over flap20such that the change-over flap20either opens further (i.e. the change-over flap20moves in the direction R) or completely pivots into the first switch position20A. However, if the measured temperature value indicates a drive motor70that is too warm, the control device30sends a corresponding signal to the change-over flap20such that the change-over flap20either opens further (i.e. the change-over flap20moves in the direction R′) or completely pivots into the second switch position20B. If the measured temperature values indicate simultaneous heating of the storage battery200and the drive motor70, the control device30adjusts the change-over flap20to a middle switch position20M such that both the storage battery200and the drive motor70are correspondingly cooled. In this case, it should be noted that the control device30can adjust the change-over flap20to any possible switch position between the first switch position20A and the second switch position20B.

The first temperature sensor and the second temperature sensor are not represented in the figures. Likewise, the connections from the control device30to the change-over flap20or to the temperature sensors are also not represented.

FIG. 7shows the hand-held power tool100according to the invention according to a fourth embodiment. The hand-held power tool100according to the fourth embodiment is substantially identical to the hand-held power tool100according to the third embodiment. Unlike the hand-held power tool100according to the third embodiment, the flow control means is configured in the form of a first slat arrangement300and a second slat arrangement400. The first slat arrangement300is in this case positioned on the first vent portion40and the second slat arrangement400is positioned on the second vent portion50. Depending on the position of the first slat arrangement300, the first vent portion40can either be completely opened, partially closed or completely closed. The first slat arrangement300and the second slat arrangement400can for this purpose be reversibly pivoted in the direction of the arrows inFIG. 7. Accordingly, depending on the position of the second slat arrangement400, the second vent portion50can either be completely opened, partially closed or completely closed. The first and second slat arrangement300,400is shown inFIG. 7in a partially closed position. The position of the slat arrangement300,400for this purpose serves to increase or reduce the respective volume flow through the first vent potion40and the second vent portion50.

The slat arrangements300,400are connected to the control device30such that (as already described above with respect to the third embodiment) the control device30either further opens or closes the slat arrangements300,400corresponding to the respectively measured temperature value in the storage battery200or in the drive motor70.

LIST OF REFERENCE NUMERALS

V volume flow

U environment

20A first switch position

20M middle switch position

20B second switch position

70electric drive motor

100hand-held power tool