Hand-held power tool and battery pack for a hand-held power tool

Abstract

The application relates to a battery pack (100) for a hand-held power tool (300), having at least one interface (180) for establishing an electrical connection of the battery pack with the hand-held power tool and / or a charger, • wherein the interface has contact elements (140) for electrically contacting corresponding counter contact elements (340) on the hand-held power tool and / or corresponding counter contact elements on the charger, • wherein at least one contact element is a signal contact element (143) which is electrically connected to at least one coding element (141) of the battery pack; • a battery pack electronics, wherein the battery pack electronics is designed to provide information about the battery pack via the at least one signal contact element, wherein the information about the battery pack is at least partially stored in the at least one coding element; • wherein the at least one coding element is connected in parallel to a dynamic circuit route in the battery pack electronics (800).

Description

TECHNICAL FIELD

[0001] The application relates to a battery pack for a hand-held power tool, to a hand-held power tool and to a charger. BACKGROUND

[0002] Electric hand-held power tools are known per se and are supplied with power via a mains connection. Alternatively, battery-operated appliances enable high flexibility in operation, since they are, inter alia, independent of the mains current. In this way, for example, outdoor work can also be carried out conveniently, so that it is often provided to use a battery pack when operating a hand-held power tool.

[0003] Such battery packs are known per se and generally have a plurality of rechargeable batteries connected in parallel and / or in series, such as three cylindrical lithium-ion cells of, for example, 3.6 volts each connected in series, which have a total voltage of 10.8 volts. The connected battery cells are connected on the one hand to the battery pack electronics and on the other hand to one another. The battery pack generally also comprises a battery pack housing, in which the battery cells are received, in particular completely or partially, by means of cell holders. Alternatively, the cell holders themselves form a battery pack housing element of the battery pack housing.

[0004] In the context of the present application, a battery pack is thus to be understood as a battery pack which preferably comprises a plurality of electrically connected, electrically chargeable battery cells which provide the energy required for the operation of a hand-held power tool and which can be installed in a replaceable manner in a cavity, an interface or the like of the hand-held power tool and of the charger. An interface is understood in particular as a device which is provided for establishing an electrical connection, directly or indirectly, with the charger and / or the discharge side, i.e. the hand-held power tool, and, if necessary, also providing a mechanical connection thereof.

[0005] The coupling of the battery pack to the hand-held power tool is done by plugging or pushing the interface of the battery pack into a complementary receptacle of the appliance housing. The interface has a contact gap in which contact elements can be arranged. If the energy of the battery pack is consumed, it can be removed and connected to a charging station with corresponding counter contact elements. If a plurality of battery packs are available, it is possible to remove the discharged battery pack from the hand-held power tool and to exchange it for a fully charged battery pack. Here, the power and the operating time of the hand-held power tool are generally determined in correspondence with the nominal voltage and the capacity of the battery pack used. It is thus important that the tool and the charger have information about the battery pack, such as the maximum charging and discharging current and the current operating temperature and internal resistance of the battery pack.

[0006] It is known from the prior art that different hand-held power tools of one voltage class have non-compatible battery packs, whereas battery packs of different hand-held power tools within one volt class, for example, screwdrivers, battery drills, impact drills, jigsaws, multi- functional tools and / or drill-screwdrivers, are generally compatible.

[0007] It is also known that battery packs can be mutually identified by means of coding with the charger and the hand-held power tool, so that other battery packs not provided for the hand-held power tool, for example, with a different nominal voltage, are not accepted by the hand-held power tool, so that the battery pack and / or the hand-held power tool are not damaged. In other cases, information is transmitted for optimizing the matching of the battery pack and the hand-held power tool or the charger.

[0008] In the prior art, this is achieved, for example, by signal contact elements arranged in the interface of the battery pack, by means of which battery pack-specific information can be transmitted to corresponding contact elements of the hand-held power tool and / or the charger. It is also possible in some cases that information is exchanged between the battery pack and the hand-held power tool and / or the charger, i.e. that information can be transmitted bidirectionally.

[0009] The signal contact elements are generally connected in the prior art on the battery pack side with coding elements, for example, coding resistors. A pull-up resistor is generally provided in the corresponding mating contact elements of the hand-held power tool and / or the charger, via which the coding resistor on the battery pack side is supplied with voltage. A measuring circuit in the hand-held power tool or the charger ascertains the resistance connected to the signal contact element, which is interpreted by the corresponding controller of the hand-held power tool or the charger as battery pack-specific information.

[0010] In parallel to the coding resistor, a capacitor or a diode is generally connected in the battery pack electronics, for example, as protection against electrostatic discharge (ESD).

[0011] It proves to be disadvantageous in principle in this context that only a limited number of information can be transmitted by the coding element according to the above-described coding element method, since the battery pack as well as the hand-held power tool and the charger and the corresponding interface are constantly being developed, wherein it is generally necessary to implement additional contact elements and mating contact elements in the interface in order to exchange additional information between the appliances. However, it is desirable for reasons of ease of use and ease of handling of the battery pack as well as the hand-held power tool to keep the required installation space for the interface as compact as possible. Furthermore, it is also necessary for reasons of compatibility with past models to change the geometry of the interface with respect to past models as little as possible. SUMMARY

[0012] It is the task of the present invention to improve the above-mentioned disadvantages and to provide an improved battery pack of the type mentioned at the outset, which can be used in a plurality of different hand-held power tools, wherein as many pieces of information as possible should be transmitted via the battery pack interface, which is as compact as possible, while being fully compatible with older hand-held power tools. Neither the recognition of the correct coding element nor the possible digital communication via the same route is restricted here.

[0013] It is a further task of the present invention to provide a corresponding hand-held power tool and a corresponding charger, which can read as many pieces of information as possible from the battery pack while being fully compatible with conventional battery packs.

[0014] These tasks are solved by the battery pack according to the present application as well as the hand-held power tool and the charger. Advantageous configurations, variants and extensions are proposed by the present invention.

[0015] The battery pack for a hand-held power tool according to the present invention has at least one interface for establishing an electrical connection of the battery pack to a hand-held power tool and / or to a charger, wherein the interface has contact elements for electrically contacting corresponding counter-contact elements on the hand-held power tool and / or on the charger, wherein at least one contact element is a signal contact element, which is electrically connected to at least one coding element of the battery pack.

[0016] a battery pack electronics,

[0017] wherein the battery pack electronics is configured to provide information about the battery pack via the at least one signal contact element, wherein the information about the battery pack is at least partially stored in the at least one coding element; and wherein the at least one coding element is electrically connected in parallel to a dynamic circuit route in the battery pack electronics.

[0018] In the context of the present application, a dynamic circuit route is understood to be a circuit route, which is variable, i.e. changing, in terms of certain electrical properties, in particular in terms of the voltage applied to the circuit route and / or the current strength flowing through the circuit route, over time. In the context of the present application, the properties of a dynamic circuit route are also referred to as temporal behavior.

[0019] The person skilled in the art recognizes that the dynamics or temporal behavior of the circuit route connected in parallel to the coding element provides the possibility to encode and transmit at least one further 1-bit information via the signal contact element in addition to the coding resistance to the hand-held power tool and / or to the charger, whereby the arrangement of a further signal contact element for transmitting said additional information is superfluous. This is achieved in such a way that the controller of the hand-held power tool or of the charger recognizes the dynamics and interprets it accordingly.

[0020] Advantageously, the temporal behavior is electrically adapted in a favorable manner, such that the dynamics required for the digital communication between the battery pack and the hand-held power tool or the charger are changed at most in an unnoticeable manner. In particular, it is ensured that the required switching threshold is not significantly influenced in time. It is thereby ensured that the function is not influenced, but at the same time at least one further information can be transmitted via the coded interface analogously.

[0021] In an embodiment, the battery pack electronics are provided for delivering the supply voltage to the at least one coded element via a series resistor in the hand-held power tool or the charger, wherein a dynamic circuit route is provided for influencing the temporal course of the measured voltage on the coded element. In this embodiment, the existence of the temporal behavior is measured, for example, by a microcontroller on the hand-held power tool side or the charger side, in that the voltage curve on the coded element is measured during and after the charging process of the circuit. In connection therewith, arbitrary 1-bit information can be coded. For a higher information depth, properties of the temporal behavior can be evaluated, for example, the slope of the voltage curve on the coded element.

[0022] Advantageously, the dynamic circuit route is provided for influencing the temporal course of the measured voltage on the at least one coded element only within a defined time period after the supply voltage is applied from the corresponding hand-held power tool and / or the corresponding charger, wherein the defined time period is preferably between 0 milliseconds and 10 milliseconds, particularly preferably between 0 milliseconds and 1 millisecond. In this way, it can be achieved in specific cases that the temporal behavior is advantageously electrically adapted in such a way that it already reaches an end value during the static identification of the coded element, for example, in such a way that the end value of the voltage difference on the signal contact element due to the dynamic circuit route is approximately zero volts. In other words, after the end of the temporal behavior, the voltage on the coded element corresponds to the voltage that also exists without the dynamic circuit route parallel to the coded element.

[0023] Preferably, in the battery pack electronics, the signal contact element and the dynamic circuit route are parallel between the common ground connection and the signal contact element.

[0024] In a preferred embodiment, the dynamics in time are achieved in that the dynamic circuit route comprises at least one first capacitor and a first resistor in series. Here, the first capacitor and the first resistor can be arranged in an RC series circuit or a CR series circuit in a known manner. The dynamics of the dynamic circuit route are produced here in that, for example, in the case of the application of a direct-current supply voltage via a pull-up resistor arranged in the interface of the hand-held power tool or the charger, the first capacitor is charged within a defined time and the voltage present on the first resistor during the charging decreases in a known manner until the current is zero when the first capacitor is fully charged. The voltage present on the first resistor is then likewise zero.

[0025] ​In one embodiment, the capacity Cx of the at least one first capacitor and the resistance value Rx of the at least one first resistor are selected such that the time constant τ = Rx * Cx of the first capacitor has a value τ < 10 milliseconds, preferably τ < 1 millisecond.

[0026] In one embodiment of the application, the dynamic circuit path comprises two or more first capacitors in parallel and / or in series and / or two or more first resistors in parallel and / or in series.

[0027] In another embodiment, the dynamic circuit path has a defined capacity value Cx and / or a defined resistance value Rx for a battery pack or a battery pack type, which produces a defined temporal behavior of the measured voltage on the coding element when a supply voltage is applied on the signal contact element from the hand-held power tool or the charger, wherein the temporal behavior can be distinguished from the temporal behavior of other battery packs or other battery pack types, for example, which do not have a dynamic circuit path or have a different type of dynamic circuit path.

[0028] In this way, in principle any number of different capacity values Cx and / or resistance values Rx can be distinguished in the temporal progression, for example, to implement an 8-bit coding.

[0029] In another embodiment, the battery pack electronics 800 comprise two or more dynamic circuit paths, wherein each of the plurality of dynamic circuit paths is connected in parallel to the at least one coding element, and wherein each of the plurality of dynamic circuit paths has at least one first resistor with a resistance value Rx,i and at least one first capacitor with a capacity Cx,i connected in series, wherein each combination of the two or more dynamic circuit paths produces a distinguishable temporal behavior on the interface to the hand-held power tool and / or the charger within the battery pack to be distinguished. In this way, in principle any number of bits can be coded, as in the previously discussed embodiments.

[0030] In general, in one embodiment it is provided that the battery pack electronics comprise two or more dynamic circuit paths, wherein each of the two or more dynamic circuit paths is connected in parallel to the at least one coding element, and wherein each of the two or more dynamic circuit paths is constructed analogously to the first dynamic circuit path in terms of its electrical zero components and its wiring.

[0031] In one embodiment of the application, a protective capacitor or a protective diode is connected in parallel to the at least one coding element. This makes it possible to protect the circuit against electrostatic discharge.

[0032] Preferably, the at least one coding element is a coding resistor, particularly preferably an ohmic resistor. In this embodiment, the ohmic resistance value of the ohmic resistor can be considered as the coding value of the at least one first coding element.

[0033] According to another aspect, the application comprises a hand-held power tool, comprising: a battery pack as described above; an interface for electrically coupling the battery pack with the hand-held power tool; at least one signal counter contact element corresponding to the signal contact element of the battery pack; and a control unit, wherein the control unit is configured to receive information about the battery pack via the at least one signal counter contact element; wherein the control unit is configured to detect and analyze the temporal progression of a measured voltage present on the at least one signal counter contact element.

[0034] The application likewise comprises a charger for charging a battery pack as described above, the charger comprising: an interface for electrically coupling the charger with the battery pack, the interface comprising at least one charging counter contact element corresponding to the signal contact element of the battery pack; and a control unit, wherein the control unit is configured to receive information about the battery pack via the at least one charging counter contact element; wherein the control unit is configured to detect and analyze the temporal progression of a measured voltage present on the at least one charging counter contact element.

[0035] Compared to the prior art, the hand-held power tool according to the application and the charger according to the application enable the reading of at least one further information with simple coding elements, for generating a distinguishable plurality of temporal progressions corresponding to a plurality of information in the case of a battery pack as described above.

[0036] It can be provided here that, on the hand-held power tool side, on the charger side, a pull-up resistor is electrically connected to the at least one signal counter contact element, respectively to the at least one charging counter contact element.

[0037] Further features, possibilities of application and advantages of the application result from the following description of embodiments of the application, which are shown in the drawings. It is to be noted here that the features shown only have a descriptive character and can be used in combination with the features of the other extensions described above and should not be understood as limiting the application in any form. BRIEF DESCRIPTION OF DRAWINGS

[0038] The application is described in detail below with reference to the drawings, in which the same reference designations are used for identical features. The drawings are schematic and show:

[0039] Figure 1 An exemplary illustration of a hand-held power tool with a battery pack according to the application is shown;

[0040] Figure 2 a perspective exploded view of an embodiment of a battery pack according to the present application is shown;

[0041] Figure 3 a schematic diagram of the electrical contact between the signal contact element on the battery pack side and the signal counter contact element on the machine side according to the prior art is shown;

[0042] Fig. 4 shows a schematic diagram of the electrical contact between the signal contact element on the battery pack side and the signal counter contact element on the machine side according to an embodiment of the present application at different points in time;

[0043] Fig. 5 shows a schematic diagram of the electrical contact between the signal contact element on the battery pack side and the signal counter contact element on the machine side according to an embodiment of the present application at different points in time; and

[0044] Figure 6 a diagram showing a voltage curve measured on a signal contact element according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0045] Figure 1 An electric power tool is shown which is constructed as a hand-held power tool 300, which is exemplarily constructed as a battery-powered screwdriver drill. Accordingly, the hand-held power tool 300 is in the shown embodiment mechanically and electrically connected with a battery pack 100 for an independent current supply from the power grid. It is pointed out, however, that the present application is not limited to a battery-powered screwdriver drill, but can be used for different hand-held power tools 300. The hand-held power tool 300 has a transmission 330 arranged in a housing 305 for transmitting a torque generated by a drive motor 335 to a drive shaft which is rotatable about an axis x, on which a tool receptacle 320 for a not shown tool is fastened. Electronic components 370 are arranged within the housing 305, which are in electronic and / or mechanical contact with the drive motor 335 and / or the transmission 330. The handle 315 serves as a placement surface for the hand of an operator of the hand-held power tool 300 and generally has a longitudinal axis y, a front face 317 which faces in the direction of the tool receptacle 320 along the axis x, a back face 316 and two side faces 318.

[0046] In the region of the handle 315, a first operating element 310 for driving the energy supply of the drive motor 335 is arranged, wherein the first operating element 310 projects from the housing 305 in a manner that is manually accessible to a user, such that, in a known manner, control and / or adjustment of the drive motor, preferably in accordance with an adjustment displacement of the first operating element 310, is possible by a pressing movement on the first operating element 310 and / or the voltage supply for the drive motor 335 can be switched on and / or off. The hand-held power tool 300 also has a second operating element 312 in the form of a push switch for setting the direction of rotation of the drive motor 335 of the hand-held power tool 300. The second operating element 312 is arranged displaceably perpendicular to the rotation axis x of the drive shaft, in particular of the tool receptacle 320 of the hand-held power tool 300, such that the second operating element 312 can be moved back and forth between a first position, a second position and a third position when being actuated. Here, the first and second positions each determine one direction of rotation of the drive motor. The user of the hand-held power tool 300 thus already recognizes in which mode of operation the hand-held power tool 300 is operating in accordance with the position of the second operating element 312. In addition, the second operating element has a third position, for example an intermediate position, between the first position and the second position, in which an electrical, electromechanical and / or mechanical interruption of the motor current takes place. For example, the operation of the first operating element 310 can be mechanically blocked, wherein the second operating element 312 acts lockingly on the first operating element 310 when being moved into the third position. Here, the second operating element 312 can be embodied as a push switch as shown or, alternatively, as a rocker switch.

[0047] The first operating element 310 and the second operating element 312 are arranged along the rotation axis x such that the first operating element and the second operating element 310, 312 can be actuated with the index finger or the middle finger. Here, the spacing between the first operating element 310 and the second operating element 312 is chosen such that one-handed operation of the hand-held power tool 300 is possible. Furthermore, both operating elements 310, 312 are arranged in the region below the rotation axis x and project from the housing 305.

[0048] In Figure 1 In the position shown, the battery pack 100 is fastened on the handle 315 of the hand-held power tool 300 and is locked by locking means. By arranging the battery pack 100 below the handle 315, the operation of the hand-held power tool 300 is not disturbed. The locking means, which are not shown in detail, comprise in particular a locking element and an actuating element 220. By actuating the actuating means 220, the battery pack 100 can be detached from the handle 315 of the hand-held power tool 300. The hand-held power tool 300 also has an interface 380.

[0049] In Figure 1The battery pack 100 shown in Fig. 1 is embodied as a push-in battery pack and has an interface 180 that corresponds to an interface 380 of the hand-held power tool 300. Instead of a push-in battery pack it is also possible to embody a swivel battery pack or a pivot battery pack, wherein the battery pack 100 can be detachably locked on the housing 305 of the hand-held power tool 300 on the side opposite the pivot axis by means of a click, a screw, a clamping or a clamping. In this way it is effectively prevented that the battery pack falls possibly from the housing 305.

[0050] For detachable mounting of the battery pack 100 on the hand-held power tool 300 or on a charger, the battery pack 100 has an interface 180 for releasable mechanical and electrical connection with a corresponding interface 380 of the hand-held power tool 300 or with a corresponding interface of the charger. When mounting the battery pack 100, receiving means, for example guide grooves and guide ribs, of the hand-held power tool 300 or of the charger form a fit with corresponding guide elements of the battery pack 100 for receiving the battery pack 100, wherein the battery pack 100 is inserted along the receiving means and the interface 180 of the battery pack 100 is pushed into the corresponding interface 380 of the hand-held power tool 300 or into the corresponding interface of the charger. By means of the interface 180, 380 the mechanical configuration can attribute the battery pack 100 to the hand-held power tool 300 and / or to the charger.

[0051] For the sake of brevity, in the following Figure 2 In the embodiments of Figs. 1 to 5, the hand-held power tool 300 represents the appliance to which the battery pack is connected, and it will not always be mentioned that the appliance to which the battery pack 100 is connected also relates to the battery 700. Figure 3 The embodiments of Figs. 1 to 5 are also similarly applicable to the arrangement of the battery pack 100 on the charger 700.

[0052] For locking the battery pack 100 on the handle 315 of the hand-held power tool 300, the battery pack 100 is pushed along the handle 315 and more precisely along a lower surface of the handle 315 that is oriented essentially perpendicular to the longitudinal direction y of the handle 315. In the Figure 1 In the position shown in Fig. 1, the battery pack 100 is locked on the handle 315 by means of locking means. The locking means comprise in particular the locking element 210 and the actuating element 220 shown in Figure 2 By actuating the actuating means 220 the battery pack 100 can be detached from the handle 315 of the hand-held power tool 300. After unlocking the battery pack 100 it can be detached from the handle 315. In mounting the battery pack 100 on the hand-held power tool 300, the locking element 210 forms a fit with a corresponding receiving portion, not shown in detail, in the handle 315 of the hand-held power tool 300.

[0053] As in the embodiments of Figs. 1 to 5, the battery pack 100 is embodied as a push-in battery pack and has an interface 180 that corresponds to an interface 380 of the hand-held power tool 300. Instead of a push-in battery pack it is also possible to embody a swivel battery pack or a pivot battery pack, wherein the battery pack 100 can be detachably locked on the housing 305 of the hand-held power tool 300 on the side opposite the pivot axis by means of a click, a screw, a clamping or a clamping. In this way it is effectively prevented that the battery pack falls possibly from the housing 305. Figure 2The interface 180, which is identifiable in the exploded view, also comprises contact elements 140 for electrical contacting of the battery pack 100 with the hand-held power tool 300 or the charger. The contact elements 140 comprise voltage contact elements which serve as charging and / or discharging contact elements and comprise signal contact elements which enable signal transmission from the battery pack 100 to the hand-held power tool 300 and / or signal transmission from the hand-held power tool 300 to the battery pack 100, wherein "signal transmission" is understood here as the transmission of information, which in the simplest case is a 1-bit information such as "0" or "1", but can also be, for example, a value of a voltage or a resistance.

[0054] As mentioned in the introduction, the determined signal contact elements are connected on the battery pack side with coding elements, for example coding resistors, which encode information for the hand-held power tool 300 or the charger, for example the maximum charging and discharging current, the current operating temperature and the internal resistance of the battery pack. In the corresponding mating contact elements of the hand-held power tool and / or the charger, a pull-up resistor is usually arranged, via which the coding resistor on the battery pack side is supplied with a voltage.

[0055] The simplest circuit diagram of this known arrangement is shown in Figure 3 . In Figure 3 Figs. 1 to 5, the interface between the battery pack 100 or the battery pack electronics 800 and the hand-held power tool 300 or the charger is shown by dashed lines. In Figure 3 Figs. 1 to 5, the connection between the electronics of the battery pack and the electronics of the hand-held power tool 300 is shown in solid lines, the contact elements of the interface on the battery pack side and on the machine side, which are arranged between the appliances, are not shown. Also not shown is the configuration of the battery pack electronics for providing information about the battery pack 100 to further units of the hand-held power tool 300 via the at least one signal contact element 143. The information about the battery pack 100 is at least partially stored in the at least one coding element 141, which will be described in more detail later.

[0056] In the example shown in Figure 3 , the coding element 141 is a resistor with a resistance value Rc. A pull-up resistor 341 is shown on the hand-held power tool 300 side, via which the coding element 141 is supplied with a current. In the shown embodiment, a supply voltage Vcc is applied across the pull-up resistor 341 and the coding element 141. After application of the supply voltage Vcc, a measurement circuit in the hand-held power tool or the charger determines the resistance connected to the signal contact element, which is interpreted by a corresponding controller of the hand-held power tool or the charger as battery pack-specific information.

[0057] As mentioned at the outset, the type of information transmission is limited, in the embodiment shown to resistance values.

[0058] In order to eliminate this disadvantage and at the same time to ensure full compatibility and functionality with existing appliances, according to one aspect of the application it is maintained that the measuring voltage is applied to the at least one coding element 141 via the battery pack electronics 800. Furthermore, as shown in Figure 4b , according to the application the coding element 141 is connected in parallel to the dynamic circuit route in the battery pack electronics 800, which is described according to the embodiment shown in Fig. 4 of the application. In Figs. 4 and 5, the features already described in Figure 3 have the same reference numerals as in Figure 3 .

[0059] In the embodiment of Fig. 4, the dynamic circuit route comprises at least one first resistor 241 of resistance value Rx and a first capacitor 243 of capacity Cx, which are connected in series. Here, according to the embodiment of the application, viewed from the interface, the first resistor 241 is arranged before the first capacitor 243 (R-C-series circuit) or after the first capacitor (C-R-series circuit), which makes no difference for the technical effect desired here.

[0060] In the battery pack electronics 800, the coding element 141 and the dynamic circuit route are connected in parallel between a common ground connection and the signal contact element 143, which is schematically indicated by the respective ground symbols in the figure.

[0061] If a voltage Vcc is applied to Figure 4b the circuit shown, then, from an electrical point of view, for a first capacitor 243 which is completely discharged at the start, i.e. empty, the situation shown in Figure 4a occurs, in which the voltage on the dynamic circuit route and the static route containing the coding element 141 which is constant in time is divided by a voltage divider comprising the pull-up resistor 341 and a parallel circuit consisting of Rc and Rx. This is particularly advantageous, since it is thereby ensured that the switching threshold required in some cases for the digital communication between the battery pack 100 and the hand-held power tool 300 is exceeded without a noticeable additional time delay.

[0062] It is recognized that the capacitor 243 charges to its final value with a time constant τ = Rx*Cx according to its capacity Cx and the resistance Rx of the coding element 141 in the case of the application of the measuring voltage Vc. If the final value is reached, no current flows through the dynamic circuit route any more, and the static voltage value corresponds to the voltage divider comprising the pull-up resistor 341 and the coding element 141, which is shown schematically in Figure 4c . From an electrical point of view, the static system can thus be seen as if the dynamic circuit route did not exist.

[0063] In an embodiment of the application, the time constant τ = Rx*Cx is designed such that at the point in time of the static measurement of the encoding element 141 the first capacitor 243 is sufficiently charged so that deviations from the static system shown in Fig. 3 of the prior art can be neglected. Preferably, the capacity Cx of the at least one first capacitor 243 and the resistance value Rx of the at least one first resistor 241 are chosen such that the time constant τ = Rx*Cx of the first dynamic circuit route has a value τ < 10 milliseconds, preferably τ < 1 millisecond. Figure 3

[0064] In this embodiment, the dynamic circuit route is provided for influencing the temporal course of the measurement voltage Vc only within a defined time period after the connection of the battery pack 100 to the corresponding hand-held power tool 100 or to the corresponding charger 700. The influence on the temporal course of the measurement voltage Vc can be detected and analyzed by the correspondingly configured control unit of the hand-held power tool 300 or of the charger.

[0065] To illustrate this case, Figure 6 The temporal course of the voltage Vc present on the encoding element 141 after the application of the supply voltage Vcc is shown exemplarily as explained in connection with Fig. 4. On the horizontal x-axis is the time, on the vertical y-axis is the normalized voltage on the encoding element 141.

[0066] The temporal course identified with the curve 1001 provided with dots is based on the exemplary configuration of the circuit shown in Fig. 3 comprising the pull-up resistor 341, the encoding element 141 and the first resistor 241 and the first capacitor 243 forming an RC circuit. The consecutive curve 1002 not further identified corresponds to a circuit without dynamic circuit route implemented in accordance with the prior art, which has the further constant components: the pull-up resistor 341 and the encoding element 141. Figure 4b It can be seen that the small difference of the rising edge of the temporal courses 1001, 1002 immediately after the application of the supply voltage Vcc and the static state in which both temporal courses 1001, 1002 again approximate each other. The voltage curve measurable in the time window ΔT in between is characterized by the deviation of the two temporal courses 1001, 1002 in the area 1003, which is influenced by the electrical properties of the dynamic circuit route and allows to derive the capacity Cx and / or the resistance value Rx. The existence of the temporal manifestation can be monitored, for example, by the microcontroller of the hand-held power tool 300 or of the charger in that the voltage on the encoding element 141 is measured during the charging process of the circuit. Arbitrary 1-bit information can be coded in addition. For higher information depths, the properties of the temporal manifestation can be evaluated.

[0067]

[0068] ​​In order to protect the battery pack electronics 800 from electrostatic discharge, in the prior art a protective capacitor 145 or a protective diode can be connected in parallel to the at least one coding element 141, which is shown in Figure 5b . Figure 5b It is also shown that the circuit is extended according to the application with a dynamic circuit route, which comprises a first resistor 241 of resistance value Rx and a first capacitor 243 of capacity Cx, which are connected in series, as shown in Figure 4b .

[0069] If a voltage Vcc is applied to the circuit shown in Figure 5b , then, from an electrical point of view, the case shown in Figure 5a occurs, in which the protective capacitor 145 allows a short circuit to ground and begins to charge by means of the current.

[0070] The charging process results in that, immediately after the supply voltage Vcc is applied, the current on the first capacitor 241 is equal to zero and the first capacitor 241 only begins to charge as the protective capacitor 145 gradually charges. In the case where the protective capacitor 145 and the first capacitor 241 are fully charged, from an electrical point of view, the system shown in Figure 5c occurs, which is identical to the system in Figure 4c .

[0071] In a preferred embodiment, the dynamic circuit route is characterized by a capacity value Cx and / or a resistance value Rx, which is unique to the battery pack, which, in the case where a supply voltage is applied to the signal contact element from a hand-held power tool or a charger, produces a time behavior of the measured voltage on the coding element, which is unique to the battery pack, and which can be distinguished from the time behavior of other battery packs or battery pack types, which are characterized, for example, by a dynamic circuit route with different capacity values Cx and / or resistance values Rx or by not containing a dynamic circuit route.

[0072] In another embodiment, the battery pack electronics 800 comprise two or more dynamic circuit routes, wherein each of the plurality of dynamic circuit routes is connected in parallel to the at least one coding element 141, wherein each of the plurality of dynamic circuit routes has at least one first resistor 241 of resistance value Rx,i and at least one first capacitor 243 of capacity Cx,i, which are connected in series. In this way, in principle any number of bits can be coded, as in the previously discussed embodiments.

[0073] In general, in an embodiment, it is provided that the battery pack electronic component 800 comprises two or more dynamic circuit routes, wherein each of the plurality of dynamic circuit routes is parallel to the at least one coding element 141, wherein each of the plurality of dynamic circuit routes is constructed similar to the first dynamic circuit route in terms of its electrical zero component and its wiring.

[0074] Although the application has been explained in detail by preferred embodiments, those skilled in the art can also provide other combinations of the features mentioned without departing from the scope of protection of the application.

Claims

1. Battery pack (100) for a hand-held power tool (300), having: at least one interface (180) for establishing an electrical connection of the battery pack (100) with a hand-held power tool (300) and / or a charger, the interface (180) having a contact element (140) for electrically contacting a corresponding mating contact element (340) on the hand-held power tool (300) and / or a corresponding mating contact element on the charger, wherein one contact element (140) is a signal contact element (143) which is electrically connected with one coding element (141) of the battery pack (100), battery pack electronics (800), wherein the battery pack electronics (800) are provided for providing information about the battery pack (100) via the signal contact element (143), wherein the information about the battery pack (100) is at least partially stored in the coding element (141), characterized in that the battery pack electronics (800) comprise two or more dynamic circuit routes, wherein each of the two or more dynamic circuit routes is connected in parallel to the coding element (141), wherein each of the two or more dynamic circuit routes has at least one first resistor (241) and at least one first capacitor (243) connected in series, the first resistor having a resistance value and the first capacitor having a capacity, wherein each combination of the two or more dynamic circuit routes produces a distinguishable temporal behavior on the interface to the hand-held power tool (300) and / or the charger within a battery pack to be distinguished. The battery pack electronics (800) are provided for transmitting a supply voltage to the coding element (141) via a series resistor in the hand-held power tool or the charger, and the dynamic circuit routes are provided for influencing the temporal course of a measured voltage on the coding element (141). wherein The dynamic circuit routes are provided for influencing the temporal course of a measured voltage on the coding element (141) only within a defined time period after the supply voltage is applied from a corresponding hand-held power tool (300) or a corresponding charger (700), wherein the defined time period is between 0 milliseconds and 10 milliseconds. In the battery pack electronics (800), the signal contact element (143) and the dynamic circuit routes are connected in parallel between a common ground connection and the signal contact element (143). The capacity value Cx of the at least one first capacitor (243) and the resistance value Rx of the at least one first resistor (241) are selected such that the time constant τ = Rx * Cx of the first capacitor (243) has a value τ < 10 milliseconds. ​ ​ ​ ​ 2. The battery pack (100) according to claim 1, characterized in that ​ 3. The battery pack (100) according to claim 2, characterized in that ​ 4. The battery pack (100) according to claim 1 or 2, characterized in that ​ 5. The battery pack (100) according to claim 1 or 2, characterized in that ​ 6. The battery pack (100) according to claim 1 or 2, characterized in that The dynamic circuit path has a defined capacitance value Cx and / or a defined resistance value Rx, which, in the case of the supply voltage being applied to the signal contact element (143) from the hand-held power tool (300) or the charger (700), produces a defined temporal representation of the measured voltage on the coding element (141), wherein the temporal representation is distinguishable from the temporal representation of other battery packs or from the temporal representation of other battery pack types.

7. The battery pack (100) according to claim 3, characterized in that The defined time period is between 0 milliseconds and 1 millisecond.

8. The battery pack (100) according to claim 6, characterized in that The time constant τ = Rx * Cx of the first capacitor (243) has a value τ < 1 millisecond.

9. The battery pack (100) according to claim 1 or 2, characterized in that A protection capacitor (145) or a protection diode is connected in parallel to the coding element (141).

10. The battery pack (100) according to claim 1 or 2, characterized in that The coding element (141) is a coding resistor.

11. The battery pack (100) according to claim 1 or 2, characterized in that The coding element (141) is an ohmic resistor, and the coding value of the coding element (141) is the ohmic resistance value of the ohmic resistor.

12. A hand-held power tool (300), comprising a battery pack (100) according to any one of claims 1 to 11; an interface for electrically coupling the battery pack (100) with the hand-held power tool (300), the interface comprising at least one signal counter contact element corresponding to the signal contact element (143) of the battery pack (100); and a control unit, wherein the control unit is configured to receive information about the battery pack (100) via the at least one signal counter contact element; wherein the control unit is configured to detect and analyze the temporal course of a measured voltage present on the at least one signal counter contact element.

13. The hand-held power tool (300) according to claim 12, characterized by A pull-up resistor (341) is electrically connected to the at least one signal counter contact element.

14. A charger for charging a battery pack according to any one of claims 1 to 11, the charger comprising: an interface for electrically coupling the charger with the battery pack (100), the interface comprising at least one charging counter contact element corresponding to the signal contact element (143) of the battery pack (100); a control unit, wherein the control unit is configured to receive information about the battery pack (100) via the at least one charging counter contact element; wherein the control unit is configured to detect and analyze the temporal course of a measured voltage present on the at least one charging counter contact element.

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