EP3560063A1

EP3560063A1 - Hand tool system

Info

Publication number: EP3560063A1
Application number: EP17822192.5A
Authority: EP
Inventors: Juergen Mack
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2016-12-21
Filing date: 2017-12-08
Publication date: 2019-10-30
Also published as: DE102016225730A1; WO2018114394A1; CN110168851A; US20190326771A1

Abstract

The invention describes a hand tool system comprising a hand-held power tool (300), a rechargeable battery pack (100), a charger (700), at least one temperature sensor, at least one interface (780) for electrically and/or mechanically coupling the charger to the rechargeable battery pack to be charged and a control unit for controlling the charging operation, wherein the hand tool system also comprises at least one heating means for heating the charger and/or the rechargeable battery pack, and wherein the control unit is set up to receive at least one temperature signal from the temperature sensor. In this case, the temperature signal represents a temperature of the charger and/or of the rechargeable battery pack and/or of rechargeable battery cells in the rechargeable battery pack. The control unit is also set up to compare the transmitted temperature with a predefined threshold value and to heat the charger and/or the rechargeable battery pack before the start of the charging operation via the heating means if the temperature transmitted using the temperature signal is below the predefined threshold value.

Description

title

H a d d w th k s u g s vste m

The present invention relates to a hand tool system according to claim 1.

Electric hand tool machines, such as impact wrenches, drills, angle grinders, jigsaws, circular saws or planing machines for craftsmen or DIY needs usually have either an AC motor or a DC motor as the drive motor. While the former is usually fed via a mains cable with AC power from the grid, the electrical energy for supplying the DC motor usually comes from a so-called battery pack, a rechargeable battery in a couplable to the housing of the power tool housing, the coupling of the both housing is electrically connected to the power supply lines of the DC motor.

Such battery packs are basically known and have rechargeable accumulators, usually a plurality of battery cells connected in parallel and / or series connection. In the course of this application is under a battery pack thus preferably consisting of several electrically interconnected battery cells Akkumulatorenpaket understand that can store electrical energy and supplies the energy for the operation of the power tool and interchangeable in a chamber, an interface or the like of the power tool is added.

Charging the battery packs is usually done via a coupling of the battery pack to a charger, so that electrical energy can be transmitted via cable and conductor. Alternatively, the charging via a wireless and wireless power transmission is possible, the technique is usually based on the near field transmission. These are in particular the Coupling by magnetic induction (MI), magnetic resonance (MR) and capacitive fields. In inductive coupling with magnetic induction, energy is transferred from the energy transmitter, the primary coil, to the energy receiver, the secondary coil, via magnetic fields. In this principle, an RF alternating current with a frequency of 100 kHz to 205 kHz in the primary coil generates a magnetic field which is induced in the secondary coil and generates an induction voltage there.

In the case of the battery packs, it proves to be disadvantageous that charge temperature ranges specified by the cell manufacturer must be adhered to in order to avoid damage to the battery cell and / or the battery pack. This is especially important for battery packs with chemically lithium-based battery cells. For the user or customer of the power tool, however, this can mean that a desired charging process does not start or has to be delayed and / or terminated prematurely, which may mean that a minimum amount of charge necessary for operation can not be achieved, which in turn does not allow operation of the power tool is ensured and there can be an inevitable interruption of work.

In addition, the charging of the battery packs is more often on the move and the classic areas, such as the workshop or the like leaves and thus the charging must be done under widely varying temperature conditions. Especially when charging in motor vehicles is to be expected with particularly difficult climatic conditions, since too low outside temperatures specified by the cell manufacturer charging temperature ranges can not be met, so that the battery packs to be charged must first be removed from the vehicle and warmed up in a warmer environment ,

Disclosure of the invention

The object of the invention is to improve the abovementioned disadvantages and to provide a hand tool system with an optimized charging process, which is constructed inexpensively and simply. This object is achieved by a hand tool system according to claim 1. Advantageous embodiments, variants and developments of the invention can be found in the dependent claims.

According to the invention, a hand tool system comprises a hand tool, a battery pack, a charger, at least one temperature sensor, at least one interface for the electrical and / or mechanical coupling of the charger to the battery pack to be charged and a control unit for controlling the charging process; the charger for the

Charging the battery pack of the power tool is suitable and has a charging electronics. According to the invention it is provided that the hand tool system further comprises at least one heating means for heating the charger and / or the battery pack, and that the control unit is arranged for receiving at least one temperature signal of the temperature sensor.

In this case, the temperature signal is a temperature of the charger and / or the battery pack and / or located in the battery pack rechargeable batteries again. The control unit is further configured to compare the transmitted temperature with a predefined threshold value and to heat the charger and / or the battery pack via the heating medium before starting the charging process when the temperature transmitted via the temperature signal is below the predefined threshold value. As a result, the entire environment of the hand tool system, the charger and / or the battery pack and / or located in the battery pack rechargeable battery cells is heated.

Advantageously, the charger is an inductive charger for contactless and / or wireless energy transmission. It is advantageous if the charger comprises at least one designed as a primary coil induction coil, which is intended, in at least one operating state by an applied electrical energy, in particular by an AC voltage, a

To generate magnetic field, which generates in at least one formed as a secondary coil inductive coil of the battery pack an induced AC voltage, which is used after rectification for charging the battery pack. In principle, the primary coil is intended to convert an electromagnetic alternating field into an alternating electrical current and / or vice versa. versa. It is advantageous if the alternating field has a frequency of 10 - 500 kHz, particularly preferably 100 - 150 kHz. Basically, different hand tool with different battery packs require different charging voltages, so that the primary and secondary coils must be adapted to the respective devices.

In a preferred embodiment, the control unit is configured to compare the transmitted temperature upon request of a loading operation by a user with the predefined threshold value.

In a particularly preferred embodiment, the control unit is further configured to heat the heating means to a previously defined optimum charging temperature, wherein the optimum charging temperature is preferably greater than or equal to the predefined threshold value. Thus, the charging process is started as soon as the temperature of the battery cells is within a permissible charging temperature range. Thus, the waiting time to reuse of the battery pack can be significantly reduced by the warm-up. In addition, a removal of the rechargeable batteries from the vehicle is unnecessary to heat them otherwise.

It has proven to be particularly advantageous that the control unit is set up to emit a signal upon reaching the previously defined optimum charging temperature and / or begins charging. Preferably, the heating power of the heating element is between 0.2 watts and 20 watts, advantageously between 0.5 watts and 15 watts, more preferably between 2 watts and 10 watts, particularly preferably between 5 watts and 10 watts. Advantageously, the control unit is designed such that when the defined optimum charging temperature is reached, the charging process only begins when a charging capacity of the battery pack falls below a predetermined limit value. In a preferred embodiment, the control unit is configured to receive at least a first temperature signal and / or a second temperature signal via the interface. It has proven to be an advantage that the first temperature signal is suitable for transmitting the temperature of the battery pack and / or the temperature of the battery cells in the battery pack and that the second temperature signal is suitable for transmitting the temperature of the charger.

In a particularly preferred embodiment, at least one contact element of the interface comprises at least one temperature sensor.

According to the invention it is particularly advantageous if the heating means is designed as an electric heating element, and is preferably formed by a coil used in the charging electronics of the charger, particularly preferably by an energy-emitting primary coil. In this case, the primary winding is subjected to a substantially kind of DC voltage, whereby a power loss sets by which the entire hand tool system and thus the battery pack can be heated. This embodiment is particularly advantageous, since it firstly uses the existing primary coil for heating, and secondly always faces the primary coil of the secondary coil of the battery pack, whereby a directed and direct heat transfer can take place. Accordingly, cost savings and a faster warm-up phase are achieved through better coupling and better directed heat exchange. It has been found to be advantageous that the control unit is adapted to supply the coil used as a heating element via a relay with DC voltage and electrically connect to a local ground. In this case, the heating element is at least as long as the battery cells too cold or the charging system is too cold with energy.

In an alternative embodiment, at least one heating element, preferably two heating elements and / or a separate heating electronics are arranged within the battery pack, wherein the control unit or the heating electronics is adapted to the at least one heating element, preferably all used heating elements of the battery pack via the charger with power supply. In general, under a hand tool machine in the context of the application all hand tool machines with a displaceable in rotation or translation tool carrier, which is driven directly by a drive motor via a gear or a planetary gear, such as a drill, a drill and / or percussion hammer, a Saw, a planer, a screwdriver, a milling cutter, a grinder, an angle grinder, a garden implement, in particular a mower, a sucker and / or a multi-function tool are understood. As transmission of electrical energy should be understood in this context, in particular, that the power tool is powered by the battery pack with energy.

Battery cells with a cell chemistry which provides a high power and / or energy density are preferably suitable for supplying power to the handheld power tool. In principle, the battery cells used can be lead-acid cells, NiCd battery cells, NiMH battery cells, but in particular lithium-ion cells. The battery cells can be formed by battery cells of different nominal voltages, for example rated voltages of 1.2 V, 1.5 V or advantageously approximately 3.6 V. The battery cells preferably have a cylindrical shape, whereby other forms that appear appropriate to the person skilled in the art are possible. Advantageously, the battery pack has a plurality of battery cells, for example at least two, three, four, five or ten. The battery cells are connected in parallel and / or in series. In particular, in the case of lithium-ion cells, it is possible to combine a plurality of battery cells into battery cell blocks in which a plurality of battery cells are connected in a parallel circuit. It is particularly advantageous that the cell holder can accommodate battery cells with different diameters and lengths, whereby the application of the cell holder or the cell carrier can be achieved in different battery packs. It is also conceivable that the battery pack is also realized as a fuel cell, capacitor or as otherwise, one skilled in the art seemingly energy storage or as a combination / increase of those.

In this context, a "battery pack" is to be understood as meaning, in particular, an energy storage unit, in particular an inductive charging coupler Energy storage unit, understood to have at least one formed as a secondary coil induction coil.

An inductive charging unit is to be understood as meaning a unit for charging the battery cell, which receives a charging current via induction and which comprises at least the inductive charging coil and, advantageously, inductive charging electronics. The inductive charging unit preferably also comprises at least one coil core for increasing an inductance of the at least one inductive charging coil.

In this context, a coil core should in particular be understood to mean a device which is intended to bundle an electromagnetic field. In particular, the coil core is at least essentially formed by a magnetic material, in particular a ferromagnetic material, in particular a soft magnetic material.

In this context, an inductive charging coil is to be understood as meaning, in particular, a coil having at least one winding of an electrically conductive material which is provided to receive, in at least one operating state, an electrical energy which is emitted during a charging process by an inductive charging coil of an inductive charging device and to supply via the charging electronics of a battery cell. In particular, the inductive charging coil is provided to convert an electromagnetic alternating field into an alternating electrical current and / or vice versa. The alternating field preferably has a frequency of 10 to 500 kHz, particularly preferably of 100 to 150 kHz.

Before preferably the inductive charging coil is formed as a wound coil, alternatively, the coil could be formed as a coil applied to a circuit board. In particular, a charging process is to be understood as a process in which an energy is inductively transmitted from the inductive charger 700 to the battery pack.

Other features, applications and advantages of the invention will become apparent from the following description of the embodiments of the invention, which are illustrated in the figures. It should be noted that the features shown have only a descriptive character and also in Combination with features of other developments described above and are not intended to limit the invention in any way.

drawings

The invention will be explained in more detail below with reference to preferred embodiments, wherein the same reference numerals are used for the same features. The drawings are schematic and show:

1 shows an example of a view of a hand tool with an inserted battery pack.

Fig. 2 is a perspective view of a charger;

3 is a perspective view of a battery pack;

4 is a side view of a first embodiment of a battery pack that may be used in a hand tool system according to the present invention;

Fig. 5 is a side view of a second embodiment of a battery pack that may be used in a hand tool system according to the present invention;

Fig. 6 is a plan view of a third embodiment of a battery pack which may be used in a hand tool system according to the present invention; and

Fig. 7 is a detail of a block diagram of a possible embodiment of a charging electronics of an inductive charger, which can be used in a hand tool system according to the present invention. FIG. 1 shows an electrical appliance embodied as a handheld power tool 300, which is configured by way of example as a cordless drill / driver. Accordingly, the power tool 300 in the illustrated embodiment for off-grid power supply is mechanically and electrically connected to a battery pack 100. It should be noted, however, that the present invention is not limited to cordless drill drivers, but rather may be applied to various handheld power tools 300. The portable power tool 300 has a gear 330 arranged in a housing 305 for transmitting a torque generated by a drive motor 335 to a drive shaft rotating about an axis x, to which a tool holder 320 for a tool, not shown, is attached, and a handle 315 , Within the housing 305, an electronics 370 is arranged, which is in electronic and / or mechanical contact with the drive motor 335 and / or the gear 330. The handle 315 serves as a support surface for a hand of an operator of the portable power tool 300 and typically has a longitudinal axis y, a front side 317, which points along an axis x in the direction of the tool holder 320, a rear side 316, and two side surfaces 318. In the region of the handle 315, a first operating element 310 for the power supply of the drive motor 335 is arranged, wherein the first operating element 310 protrudes out of the housing 305 for the user manually accessible, so that in a known manner by a pressure movement of the first operating element 310, a control and / or regulation of the drive motor preferably in dependence on the adjustment path of the first

Operating element 310 can be made possible, and also the power supply for the drive motor 335 can be switched on and / or off. Furthermore, the handheld power tool 300 has a second operating element 312 in the form of a slide switch for setting the direction of rotation of the drive motor 335 of the handheld power tool 300. The second operating element 312 is displaceably arranged perpendicular to the axis of rotation x of the drive shaft, in particular the tool holder 320 of the handheld power tool 300, so that the second operating element 312 can be moved between a first position, a second position and a third position when actuated. The first and second positions respectively define a direction of rotation of the drive motor. Thus, the user of the portable power tool 300 can already recognize from the positions of the second operating element 312 in which working mode the portable power tool 300 operates. In addition, the second switching element between the first position and the second position, a third position, for example, a center position, wherein in the third

Position an electrical, electro-mechanical and / or mechanical interruption of the motor current takes place. For example, the operation of the first switching element 310 may be mechanically locked, wherein the second operating element 312 acts on the first switching element 310 in a locking manner when moving into a third position. In this case, the second operating element 312 as shown as

Slide switch or alternatively be designed as a toggle switch.

The first operating element 310 and the second operating element 312 are arranged along the axis of rotation x such that it is possible to operate both the first and the second operating element 310, 312 with the index finger or middle finger. The distance between the first operating element 310 and the second operating element 312 is selected such that one-handed operation of the handheld power tool 300 is possible. Both operating elements 310, 312 are furthermore arranged in a region below the axis of rotation x and protrude out of the housing 305.

In the position shown in Figure 1, the battery pack 100 is attached to the handle 315 of the power tool 300 and locked by locking means. The arrangement of the battery pack 100 below the handle 315, the operation of the power tool 300 is not disturbed. The locking means, not shown in detail, include, inter alia, a locking element and an actuating element 220. By actuation of the actuating means 220, the battery pack 100 can be released from the handle 315 of the portable power tool 300. Furthermore, the handheld power tool 300 has an interface 380.

The battery pack 100 shown in FIG. 1 is designed as a sliding coupler, and has an interface 180 corresponding to the interface 380 of the portable power tool 300. As an alternative to Schiebeakkupack also a version as a swivel or Schwenkakkupack is possible, wherein the battery pack 100th On the opposite side of the pivot axis by latching, screwing, jamming or clamping on the housing 305 of the power tool 300 can be releasably locked. In this way, a possible drop of the battery pack from the housing 305 can be effectively counteracted.

For releasably attaching the battery pack 100 to a hand tool 300 or to a charger 700, the battery pack 100 has an interface 180 for releasable mechanical and electrical connection to a corresponding interface 380 of the power tool 300 or a corresponding interface 780 of the charger 700. The battery pack 100 can be assigned to the handheld power tool 300 and / or the charger 700 via the interfaces 180, 380, 780.

FIG. 2 shows a charging device 700. The charging device 700 is connected to the power supply via a mains cable 790 and has charging electronics, not shown, which is designed to control the charging process of a battery pack 100 shown in detail in FIGS. 3 to 6.

The charging device 700 illustrated in FIG. 2 has a charging interface 780 in order to produce a mechanical and electrical connection between the charging device 700 and the battery pack 100 with a corresponding interface 180 of the battery pack 100 shown in FIG. In the illustrated embodiment, the charging interface 780 has mating contact elements 740 that cooperate with corresponding contact elements 140 of the battery pack 100 in order to both transfer charge current and to exchange information between the charger 700 and the battery pack 100. In this case, each of the mating contact elements 740 is assigned a specific function which is fixed and can not be changed. This specific function can be, for example, the transmission of predefined information in the form of a signal transmitted by a corresponding contact element of the battery pack 100 or the contacting of a fixed electrical pole of the battery pack 100 during the charging process. FIGS. 3 to 6 show various possible embodiments of a battery pack 100 that can be used in the hand tool system according to the present invention. The battery pack in each case has a housing 110 which, for example, as shown in FIG. 3, comprises a first housing component 120 and a second housing component 130. Within the housing 1 10 takes the battery pack 100 at least one, preferably and shown here a plurality of parallel or series-connected battery cells 400. The battery pack 100 is formed at least in the embodiment variant shown in Figure 3 as Schiebeakkupack.

The embodiment of a battery pack 100 shown in FIG. 4 has ten battery cells 400, which are arranged in two layers with five battery cells 400 each. Furthermore, the battery pack has three heating elements 670 and a heating control 680. In each case one heating element 670 is arranged above and one below the battery cells 400 and a third heating element 670 is arranged horizontally between the two layers of battery cells 400.

By contrast, the embodiment of a 100 shown in FIG. 5 has only one layer with five battery cells 400, so that a heating element 670 is arranged above the battery cells 400 and a heating element 670 is arranged underneath the battery cells.

6 shows a further embodiment of a battery pack 100 shown in a plan view, wherein it can be seen that in each case a heating element 670 is arranged laterally from the battery cells 400.

In principle, it is advantageous in all embodiments of the battery pack 100 with heating element 670 if the control unit or the heating electronics 680 is set up to supply the heating elements 670 used via the charging device 700 and not via the battery cells 400.

Not shown in detail, but in principle it is advantageous if the control unit is configured to receive a first temperature signal and / or a second temperature signal via the interface and / or at least one contact element of the interface directly forms a temperature sensor. FIG. 7 shows a block diagram of an inductive charging device 700 that can be used in a hand-held power system according to the present invention for contactless and / or wireless energy transmission. In the block diagram of the charging electronics of the inductive charger 700, the heating element 670 is designed in the form of a primary coil L1. The skilled artisan will take this circuit diagram directly that the capacitor C1, two switches S1 and S2, and the relay K1 cooperate such that, if necessary, the primary coil L1 is energized to retrieve the heating effect of the primary coil L1. If this is the case, the primary coil L1 is connected via the relay K1 with a DC voltage, as well as with the local ground. In this case, the capacitor C1 is bypassed. Furthermore, the S1 and S2 are switching elements of the half-bridge, for the present invention, no further explanation is required for the skilled person.

The heating power of the heating element is in the range between 0.2 watts and 20 watts, advantageously between 0.5 watts and 15 watts, more preferably between 2 watts and 10 watts, particularly preferably between 5 watts and 10 watts. In this case, the control unit of the hand tool system is designed in such a way that when the defined optimum charging temperature is reached, the charging process only begins when a charging capacity of the battery pack 100 falls below a predetermined limit value

In an alternative embodiment, not shown in detail, it would also be possible to exchange the arrangement of L1 and C1, in which case bridging C1 would no longer be necessary due to the ground reference of L1.

In addition to the described and illustrated embodiments, further embodiments are conceivable which may include further modifications and combinations of features.

Claims

claims

1 . Hand tool system comprising o a hand tool (300),

o a battery pack (100);

o a charger, wherein the charger (700) for charging the battery pack (100) of the power tool (300) is suitable and includes a charging electronics;

o at least one temperature sensor;

o at least one interface (780) for the electrical and / or mechanical coupling of the charger with an interface 180) of the battery pack (100) to be charged; and

o a control unit for controlling the charging operation, characterized in that the hand tool system further comprises at least one heating means for heating the charger and / or the battery pack (100), and that the control unit is adapted to receive at least one temperature signal of the temperature sensor, the temperature signal a Temperature of the charger and / or the battery pack (100) and / or located in the battery pack (100) battery cells (400) reproduced, wherein the control unit is further adapted to compare the transmitted temperature with a predefined threshold and the charger (700) and / or to heat the battery pack (100) via the heating element (670) prior to commencement of the charging process, when the temperature transmitted via the temperature signal is below the predefined threshold value.

2. Hand tool system according to claim 1, characterized in that the charger (700) is an inductive charger (700) for contactless and / or wireless energy transfer.

3. Hand tool system according to claim 1 or 2, characterized in that the control unit is adapted to compare the transmitted temperature when requesting a loading by a user with the predefined threshold.

4. Hand tool system according to one of claims 1 to 3, characterized in that the control unit is adapted to heat the heating element (670) to a previously defined optimum charging temperature, wherein the optimum charging temperature is preferably greater than or equal to the predefined threshold.

5. Hand tool system according to one of claims 1 to 4, characterized in that the control unit is adapted to emit a signal upon reaching the previously defined optimum charging temperature and / or starts the charging process.

6. Hand tool system according to one of claims 1 to 5, characterized in that the heating power of the heating element (670) between 0.2 watts and 20 watts, advantageously between 0.5 watts and 15 watts, more preferably between 2 watts and 10 watts, more preferably between 5 watts and 10 watts.

7. Hand tool system according to one of claims 1 to 6, characterized in that the control unit is designed such that upon reaching the defined optimum charging temperature only the charging process begins when a charging capacity of the battery pack (100) falls below a predetermined limit.

8. Hand tool system according to one of claims 1 to 7, characterized in that the control unit is adapted to receive at least a first temperature signal and / or a second temperature signal via the interface (780).

9. hand tool system according to claim 8, characterized in that the first temperature signal is adapted to the temperature of the battery pack (100) and / or the temperature of the battery pack (100) located Akkuzel- len (400) to transmit and that the second temperature signal suitable for transmitting the temperature of the charger (700).

10. Hand tool system according to one of claims 1 to 9, characterized in that at least one contact element of the interface (780) on the charger (700) comprises the at least one temperature sensor.

Hand tool system according to one of claims 1 to 10, characterized in that the heating element (670) as an electric heating element (670) is formed, and preferably by a in the charging electronics of the charger (700) used coil (L1), particularly preferably by an energy emitting primary coil is formed.

12. Hand tool system according to claim 10, characterized in that the control unit is adapted to supply the heating element (670) used as coil (L1) via a relay (K1) with DC voltage and electrically connect to a local ground.

13. Hand tool system according to one of claims 1 to 10, characterized in that the at least one heating element (670), preferably two heating elements (670) and / or separate heating electronics (680) within the battery pack (100) are arranged.

14. Hand tool system according to claim 13, characterized in that the control unit or the heating electronics (680) is adapted to the at least one heating element (670), preferably all the heating elements used

(670) of the battery pack (100) via the charger (700) with power.