EP4402767A1

EP4402767A1 - Interface module for operating an electrical consumer with at least one exchangeable energy storage device and a method for controlling the electrical consumer by means of the interface module

Info

Publication number: EP4402767A1
Application number: EP22748306.2A
Authority: EP
Inventors: Uwe Engelfried; Gerhard Walter; Helge Kuebler
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2021-09-14
Filing date: 2022-07-08
Publication date: 2024-07-24
Also published as: CN117957741A; WO2023041218A1; DE102021210157A1

Abstract

The invention relates to an interface module (34) for operating an electrical consumer (20) of a defined voltage class with at least one exchangeable energy storage device (10) that is directly incompatible with the electrical consumer (20). It is proposed that the defined voltage class of the electrical consumer (20) corresponds to an integer multiple of a battery voltage (U_Batt) of the at least one exchangeable energy storage device (10) and that the interface module (34) has a control or regulating unit (68) that monitors at least one operating parameter (U, I, T) of the exchangeable energy storage device (10) and controls an electrical load (102) of the electrical consumer (20) as a function of the monitored operating parameter (U, I, T). In addition, the invention relates to a method for controlling an electrical consumer (20) by means of an interface module (34) according to the invention.

Description

title

Interface module for operating an electrical consumer with at least one exchangeable energy store and method for controlling the electrical consumer using the interface module

Description

The invention relates to an interface module for operating an electrical load of a defined voltage class with at least one replaceable energy store that is directly incompatible with the electrical load, and a method for controlling the electrical load using the interface module.

State of the art

A large number of electrical consumers are operated with rechargeable energy stores, which are discharged accordingly by the electrical consumer and can be recharged using a charger. As a rule, such energy stores consist of a plurality of energy storage cells connected in series and/or in parallel in order to achieve a required operating voltage or capacity. If the energy storage cells are designed as lithium ion cells (Li-ion), for example, a very high power and energy density can be achieved with particular advantage.

In recent years, electrical consumers have increasingly displaced their mains-operated counterparts because they enable significantly greater flexibility independent of a stationary energy supply and rechargeable energy storage devices have become more and more powerful, so that the performance of mains-operated consumers is often not only achieved but even exceeded. On the one hand, in order to offer the customer the widest possible range of To be able to offer electrical consumers and on the other hand to be able to use an already successful concept of exchangeable energy stores, in particular exchangeable battery packs, from a specific manufacturer, different manufacturers of electrical consumers have increasingly joined forces to form so-called battery alliances, in which the electrical consumers of the different manufacturers share a common Use energy storage platform. However, this often results in the problem of incompatibility between the electrical loads from one manufacturer and the exchangeable energy storage devices from the other manufacturer. It is therefore necessary for the manufacturers of the incompatible electrical loads to adapt their respective devices to the common energy storage platform in order to be able to use them. This is associated with sometimes complex and cost-intensive measures both with regard to the electromechanical interfaces and the consumer's own electronics.

A power tool is known from WO 2016/097081, which contains a control device and an electromechanical interface device for connecting a replaceable battery pack to the power tool and for supplying the power tool with an electrical voltage from the replaceable battery pack. The interface device has a first and a second connection point and can be adjusted into at least a first and a second position. The first connection point can be used to supply the power tool with electrical voltage from a first replaceable battery pack when the interface device is set in the first position, and the second connection point can be used to supply the power tool with electrical voltage from a second replaceable battery pack when the interface device is in the second position is set.

It is the object of the invention to provide an interface module for an electrical consumer that enables universal use of a normally incompatible, exchangeable energy store on the electrical consumer while complying with all prescribed safety measures.

Advantages of the Invention To solve the task, it is provided that the defined voltage class of the electrical consumer corresponds to an integer multiple of a battery voltage of the at least one exchangeable energy store and that the interface module has a control or regulating unit that monitors at least one operating parameter of the exchangeable energy store and as a function of the monitored operating parameter controls an electrical load of the electrical consumer. Not only can otherwise incompatible replaceable energy stores and electrical loads be connected to one another with particular advantage, it is also possible to effectively avoid damage to the energy store and/or the electrical load and thereby effectively increase safety during operation.

Electrical consumers in the context of the invention should be understood to mean, for example, power tools operated with a replaceable energy store, in particular a replaceable battery pack, for machining workpieces using an electrically driven insert tool. The power tool can be designed both as a hand-held power tool and as a stationary power tool. Typical power tools in this context are handheld or stationary drills, screwdrivers, percussion drills, hammer drills, planes, angle grinders, orbital sanders, polishing machines, circular saws, table saws, chop saws and jigsaws or the like. Measuring devices operated with a replaceable energy store, in particular a replaceable battery pack, such as range finders, laser levels, wall scanners, etc., as well as garden and construction equipment such as lawnmowers, lawn trimmers, pruning saws, motor and trench cutters, robot breaker and excavator also come as electrical consumers or the like and household appliances such as vacuum cleaners, blenders, etc. in question. The invention can also be applied to electrical consumers that are simultaneously supplied with a plurality of exchangeable battery packs in order to achieve a long service life and/or high performance.

The electrical load of the electrical consumer can be designed, for example, as a brushless direct current motor (EC or BLDC motor) controlled by means of a power output stage via pulse width modulation (PWM). Other inductive, capacitive and/or ohmic loads that can be supplied with energy electrically via the exchangeable energy store are also possible are. These are well known to those skilled in the art, so that they will not be discussed further at this point.

The battery voltage of a replaceable energy store is usually a multiple of the voltage of an individual energy storage cell and results from the interconnection (in parallel and/or in series) of the individual energy storage cells. An energy storage cell is typically configured as a galvanic cell having a configuration in which one cell pole is at one end and another cell pole is at an opposite end. In particular, the energy storage cell has a positive cell pole at one end and a negative cell pole at an opposite end. The energy storage cells are preferably designed as lithium-based energy storage cells, e.g. Li-Ion, Li-Po, Li-Metal or the like. However, the invention can also be used for energy stores with Ni-Cd, Ni-MH cells or other suitable cell types. With common Li-ion energy storage cells with a cell voltage of 3.6 V, battery voltages of 3.6 V, 7.2 V, 10.8 V, 14.4 V, 18 V, 36 V, 54 V, 72 V, etc. An energy storage cell is preferably designed as an at least essentially cylindrical round cell, with the cell poles being arranged at the ends of the cylindrical shape. However, the invention is not dependent on the type and design of the energy storage cells used, but can be applied to any energy storage and energy storage cells, e.g. pouch cells or the like in addition to round cells.

An electrical load that is directly incompatible with the exchangeable energy store should be understood to mean that the exchangeable energy store and the electrical load do not have any mutually compatible electromechanical interfaces for tool-free connection without additional means and/or that the electrical load has the operating data of the exchangeable device required for safe operation Can not read and evaluate energy storage without additional means. Only via mutually compatible, electromechanical interfaces can the exchangeable energy store then be detachably coupled to the electrical consumer without tools. It is therefore particularly advantageous for the interface module to have an electromechanical interface which is compatible with the electromechanical interface of the exchangeable battery pack. In each case, a first of the electrical contacts of the electromechanical interfaces as a with a first reference potential tial, preferably a supply potential, power supply contact that can be acted upon, and a second of the electrical contacts of the electromechanical interfaces is designed as a power supply contact that can be acted upon with a second reference potential, preferably a ground potential.

The electrical wiring of the exchangeable energy store connected to the interface module is designed in such a way that the defined voltage class of the electrical consumer must correspond to an integer multiple of the battery voltage of an individual exchangeable energy store. If the interface module has a plurality of electromechanical interfaces for a corresponding number of replaceable energy stores, then each energy store must have essentially the same battery voltage. With particular advantage, the interface module can compensate for certain voltage deviations between the resulting battery voltage of the connected exchangeable energy store and the voltage class of the electrical consumer. If the interface module is operated with only a single exchangeable energy store or a plurality of exchangeable energy stores connected in parallel, the defined voltage class of the electrical load is essentially the same as the battery voltage of the individual exchangeable energy store(s). In the case of a series connection of a plurality of exchangeable energy stores, the defined voltage class of the electrical load must essentially correspond to the sum of the battery voltages of the individual exchangeable energy stores.

To monitor the exchangeable energy store and to control or regulate the electrical load that can be derived from this, the interface module has an interface to the electrical load, via which the exchangeable energy store and the electrical load can send and/or receive information, in particular about the at least one operating parameter . Correspondingly, the electromechanical interfaces of the interface module and the replaceable energy store also have at least one third contact, designed as a signal or data contact, for transmitting the at least one operating parameter. The at least one operating parameter is preferably a voltage, a current, a current integrally, a temperature, information about a temperature resistance and/or information about a coding resistor or other values for identifying the exchangeable energy store. In the case of several operating parameters used for monitoring, it is possible to use further contacts of the electromechanical interfaces designed as signal or data contacts. Alternatively, however, it is also conceivable for the signal or data to be transmitted in the sense of a power line communication directly via the first and/or the second power supply contact of the electromechanical interfaces. Corresponding methods for power line communication are known to the person skilled in the art and will not be explained further here.

In a further embodiment, the interface module has at least one switching element, in particular at least one MOSFET, by means of which the control or regulating unit of the interface module can temporarily or permanently interrupt the energy supply from the exchangeable energy store to the electrical load if the at least one operating parameter in a store exceeds or falls below the limit value stored in the control or regulation unit and/or deviates from an expected value stored in the memory. Redundancy to the safety systems present in the electrical load and/or in the replaceable energy storage device can thereby be created with particular advantage, which further increases operational safety in the event of a fault. In addition, electrical consumers and/or exchangeable energy stores can also be operated safely that do not themselves have an integrated option for interrupting the energy supply. The limit value can be a minimum or maximum permitted voltage, a minimum or maximum permitted current or a maximum permitted temperature and the expected value as a current-time profile, a resistance value of the temperature resistor or the coding resistor, an identification value of the exchangeable energy storage device or information about an interruption in the connection to the temperature resistor or to the coding resistor.

In addition, it can be provided that the control or regulation unit, depending on the state of charge of a load capacitance of the electrical load, in particular an intermediate circuit capacitance of a power output stage, of the electrical consumer chers causes a start-up protection of the electrical load when energy is resupplied by the at least one switching element after an interruption and/or prevents the interface module from being automatically reset. Thus, for example, the operator can be protected from injury immediately after connecting a replaceable energy store to a consumer that was accidentally still switched on. A corresponding protection for the operator is offered by avoiding the automatic resetting of the interface module after a detected fault condition, for example as a result of the temperature of the energy storage device having fallen back to the normal value, a fault current falling to almost zero or the like, no longer exists.

In order to protect the at least one switching element from excessive load currents immediately after the operator has switched on the electrical consumer, it is only switched on permanently when the state of charge of the load capacity of the electrical consumer has risen to a defined threshold value, for example 90%. To precharge the load capacity of the electrical consumer before it is put into operation, the control or regulating unit of the interface module controls the at least one switching element in a clocked manner. Alternatively or additionally, a specially designed charging stage can also be provided in the interface module for precharging the load capacitance.

If the electrical consumer has an electronics unit that can be woken up, the interface of the interface module can send a wake-up signal to the electronics unit of the electrical consumer in a particularly advantageous manner via a release contact designed as an open collector output and/or wake-up contact. This makes sense in particular when the electronics unit of the electrical consumer is to be woken up by connecting the exchangeable energy store in order to achieve a particularly quick response to the operation of the main switch.

In order to indicate to the operator any error states detected by the interface module and/or an interruption in the energy supply to the electrical consumer, the interface module has an optical, acoustic and/or haptic indicator. This can, for example, be an HMI (Human Machine Interface) in the form of an LC, LED, OLED, AMOLED display or the like. A simple, in particular multicolored, LED can also serve as a simple HMI. A dynamic loudspeaker or piezo for the acoustic display or a vibration motor for the haptic display are also conceivable. Provision can also be made for the display means of the interface module to be used to display operating and/or error states of the electrical load. This is particularly advantageous when the electrical load itself does not have any corresponding display means.

So that the interface module can be used as flexibly and universally as possible for a wide variety of electrical consumers, it can be designed as an exchangeable adapter. The adapter can either be designed to be exchangeable by the operator without tools or only by the manufacturer or an authorized dealer using a suitable tool. In the case of tool-free interchangeability, it makes sense for the adapter to have two electromechanical interfaces that are compatible with the electromechanical interface of the exchangeable energy store on the one hand and with the electromechanical interface of the electrical load on the other. In this case, the second electromechanical interface between the interface module and the electrical consumers includes the interface mentioned at the outset for the bidirectional exchange of information in particular.

The invention also relates to a method for controlling an electrical load using the interface module according to the invention, with at least the following steps:

• Actuating a main switch of the electrical consumer to wake up a control or regulation unit of the interface module,

• switching on at least one switching element, in particular at least one MOSFET, of the interface module for supplying energy from an energy store connected to the electrical load to the electrical load,

• Switching on an electrical load of the electrical consumer when the at least one detected operating parameter meets an expected value stored in a memory of the control or regulation unit of the interface module and/or is within stored limit values. In this way, a wake-up process that is simple and safe for the operator to start up the electrical consumer can be implemented with particular advantage. In addition, a redundant safety concept can be implemented for the electrical consumer or the exchangeable energy store connected to it.

In addition, at least the following steps are provided after switching on the at least one switching element:

• waking up an electronic unit of the electrical consumer,

• Querying at least one operating parameter recorded in the interface module by the electronics unit of the electrical consumer or sending the at least one operating parameter recorded in the interface module to the electronics unit of the electrical consumer and

• Switching on the electrical load of the electrical consumer by the electronics unit of the electrical consumer when the at least one recorded operating parameter meets an expected value stored in a memory of the control or regulation unit of the interface module and/or is within stored limit values.

In this way, in connection with the interface module, safe operation of the exchangeable energy store can be made possible, particularly for electrical loads that already have an integrated electronic unit for controlling the electrical load.

In a further step of the method, it is provided that a load capacitance, in particular an intermediate circuit capacitance of a power output stage, of the electrical load is precharged before the at least one switching element is permanently closed, with the advantages already mentioned above.

In addition, to further improve operational safety, in a further step, the energy supply from the energy store to the electrical load can be interrupted by opening the at least one switching element and/or the interface module can send a switch-off command to the electronic unit of the electrical load via an enabling contact as soon as the at least one operating parameter has been detected does not meet the expected value stored in the memory of the control or regulation unit of the interface module and/or is outside the stored limit values. Does the electronic unit react If the electrical consumer does not respond to the switch-off command from the interface module, the interface module in turn opens the at least one switching element to interrupt the power supply in the sense of a redundant safety level. In the event of a short circuit, on the other hand, the power supply is immediately interrupted, independently of the electronic unit of the electrical load.

In a further step, the at least one switching element is opened to interrupt the energy supply if the discharge current has not dropped to approximately zero within a defined period of time after the electrical load has been switched off. In this way, any fault currents can be detected with particular advantage.

Provision is also made for the interface module to be supplied with energy for a follow-up time, in particular between 5 and 15 minutes, after the main switch has been released in a step of the method, before the control or regulating unit of the interface module, which has at least one switching element for interrupting the Energy supply to the electrical consumer opens. On the one hand, this ensures very quick restarting within the run-on time and, on the other hand, reliable monitoring of the operating parameters even after the electrical consumer has been switched off.

exemplary embodiments

drawing

The invention is explained below by way of example with reference to FIGS. 1 to 6, with the same reference symbols in the figures indicating the same components with the same function.

Show it:

Fig. 1: an exchangeable energy store, which is directly incompatible with the exchangeable energy store by means of different electrical consumers of a defined voltage class can be discharged and charged using a charger, in a schematic representation,

2: a block diagram of the exchangeable energy store, the electrical consumer directly incompatible with the exchangeable energy store and an interface module according to the invention,

3: a schematic representation of the interface module accommodated in the electrical load,

4: a schematic representation of the interface module designed as an exchangeable adapter on an electrical consumer designed as a hammer drill,

Fig. 5: a first embodiment of an electromechanical interface of the interface module or the adapter in a schematic representation and

6: a second embodiment of the electromechanical interface of the interface module or of the adapter in a schematic representation.

Description of the exemplary embodiments

1 shows a replaceable energy store 10 in the form of a rechargeable replaceable battery pack 12 with an electromechanical interface 16 having a plurality of electrical contacts 14. The replaceable battery pack 12 can be charged using a charger 18 and discharged by various electrical consumers 20. For this purpose, the charging device 18 and the electrical loads 20 must each have a further electromechanical interface 22 having a plurality of electrical contacts 14 which is both electrically and mechanically compatible with the electromechanical interface 16 of the replaceable battery pack 12 . FIG. 1 is intended to illustrate that the invention is suitable for a wide variety of electrical consumers 20. For example, a cordless vacuum cleaner 24, a cordless impact wrench 26 and a cordless lawn trimmer 28 shown. In the context of the invention, however, other power tools, measuring devices, gardening tools and household appliances can also be used as electrical loads 20 .

The exchangeable battery pack 12 comprises a housing 30 which has the electromechanical interface 16 on a side wall or on its upper side 32 for the tool-free, detachable connection to the compatible, further electromechanical interface 24 of the charging device 18 or the electrical consumer 20 . In conjunction with the electrical consumer 20, the electromechanical interfaces 16, 22 are primarily used to discharge the removable battery pack 12, while they are used in conjunction with the charger 18 to charge the removable battery pack 10. The exact design of the electromechanical interfaces 16, 22 depends on various factors, such as the voltage class of the electrical load 20, the charger 18 and the exchangeable battery pack 12, as well as various manufacturer specifications. For example, two or more electrical contacts 14 can be provided for energy and/or data transmission between the replaceable battery pack 12 and the charger 18 or the electrical load 20. A mechanical coding is also conceivable, so that the replaceable battery pack 12 can only be operated on specific electrical loads 20 . Corresponding exemplary embodiments are shown in FIGS. 5 and 6 below.

As mentioned at the beginning, different manufacturers of electrical consumers 20 have increasingly joined forces to form so-called rechargeable battery alliances, in which the electrical consumers 20 from the different manufacturers use a common energy storage platform in order to be able to offer the customer the widest possible range of electrical consumers 20 and on the other hand, to be able to use an already successful and established concept of interchangeable battery packs 12 from a specific manufacturer. However, the problem often arises here that the electromechanical interfaces of the electrical consumers 20 from one manufacturer and the electromechanical interface 16 of the interchangeable battery packs 12 from the other manufacturer are incompatible with one another. It is therefore necessary to adapt the incompatible electrical loads 20 to the common energy storage platform by means of an interface module 34 (cf. FIG. 2) described below. The replaceable battery pack 12 has a mechanical locking device 36 for locking the positively and/or non-positively releasable connection of the electromechanical interface 16 of the replaceable battery pack 12 to the corresponding mating interface 22 of the interface module 34 mounted on or in the electrical consumer 20. The locking device 36 is a spring-loaded pusher 38 is formed, which is operatively connected to a locking member 40 of the exchangeable battery pack 12. Due to the springiness of the pusher 38 and/or the locking member 40, the locking device 36 automatically engages when the replaceable battery pack 12 is pushed into the mating interface 22 of the interface module 34. If an operator presses the push button 38 in the insertion direction, the lock is released and the operator can remove or push out the replaceable battery pack 12 from the electrical consumer 20 or the interface module 34 in the opposite direction to the insertion direction.

FIG. 2 shows a block diagram consisting of the replaceable energy store 10 designed as a rechargeable replaceable battery pack 12 on the left-hand side and an electrical consumer 20 that is normally incompatible with the replaceable battery pack 12 on the right-hand side. In order to establish compatibility between the exchangeable battery pack 12 and the electrical load 20, the electrical load 20 has the interface module 34, which is designed, for example, as a printed circuit board with corresponding electronic components and a mating interface 22 that matches the electromechanical interface 16 of the exchangeable battery pack.

The mutually compatible electromechanical interfaces 16 and 22 are each provided with a plurality of electrical contacts 14, with a first of the electrical contacts 14 as a power supply contact 42 that can be charged with a first reference potential Vi, preferably a supply potential V+, and a second of the electrical contacts 14 as a power supply contact 44 that can be charged with a second reference potential V2, preferably a ground potential GND. About the first and the second power supply contact 42, 44, the removable battery pack 12 on the one hand discharged by the electrical load 20 with a discharge current I and on the other hand charged by the charger 18 with a charging current (not shown in Figure 2). The current strengths of charging and discharging current can differ significantly from each other. So the discharge current at accordingly designed electrical consumers 20 can be up to 10 times higher than the charging current of the charger 18. The term "can be acted upon" is intended to make it clear that the potentials V+ and GND are not permanently applied to the energy supply contacts 42, 44, but only after the connection of the electromechanical interfaces 16, 22 of the exchangeable battery pack 12 and the interface module 34. The same applies to a discharged exchangeable battery pack 12 after connection to the charger 16.

The replaceable battery pack 12 has a plurality of energy storage cells 46, which are shown in Figure 2 as a series circuit, but can alternatively or additionally also be operated in a parallel circuit, the series circuit using the energy supply contacts 42, 44 dropping battery voltage Ußatt or voltage class of the removable battery pack 12 is defined, while connecting individual energy storage cells 46 in parallel primarily increases the capacity of the removable battery pack 12 . As already mentioned, individual cell clusters consisting of energy storage cells 46 connected in parallel can also be connected in series in order to achieve a specific battery voltage U ßatt of the exchangeable battery pack 12 with a simultaneously increased capacity. In conventional lithium-ion energy storage cells 46 with a cell voltage Uceii of 3.6 V each, a battery voltage U ßatt =Vi -V2 of 5×3.6 V=18 V drops across the energy supply contacts 42, 44 in the present exemplary embodiment. Depending on the number of energy storage cells 46 connected in parallel in a cell cluster, the capacity of common exchangeable battery packs 12 can be up to 12 Ah or more. However, the invention is not dependent on the type, design, voltage, current delivery capability, etc. of the energy storage cells 46 used, but can be applied to any exchangeable battery pack 12 and energy storage cell 46 .

An SCM preliminary stage 48 (single cell monitoring) is provided for monitoring the individual energy storage cells 46 or cell clusters of the exchangeable battery pack 12 connected in series. The SCM preliminary stage 48 has a multiplexer measuring device 50 which can be connected to corresponding taps 54 of the poles of the energy storage cells 46 or cell cluster via filter resistors 52 with high resistance. In the following, the term energy storage cell should also include the cell cluster, since these only have an influence on the capacity of the exchangeable battery pack 12, but are of equal importance for the detection of the cell voltages Uceii. tend to be. The filter resistors 54, which are designed in particular to have a high resistance, can prevent dangerous heating of the measuring inputs of the multiplexer measuring device 50, particularly in the event of a fault.

The multiplexer measuring device 50 can be switched over via a monitoring unit 56 integrated in the exchangeable battery pack 12 or also directly within the SCM preliminary stage 50 . In addition, switching elements 60 of the SCM preliminary stage 50 that are connected in parallel with the energy storage cells 46 can be closed or opened in this way in order to bring about a so-called balancing of the energy storage cells 46 in order to achieve uniform charging or discharging states of the individual energy storage cells 46. It is also conceivable that the SCM preliminary stage 50 forwards the measured cell voltages Uceii to the monitoring unit 56, so that the actual measurement of the cell voltages Uceii is carried out directly by the monitoring unit 56, for example via a corresponding analog-to-digital converter (ADC).

The monitoring unit 56 can be designed as an integrated circuit in the form of a microprocessor, ASICs, DSPs or the like. However, it is also conceivable that the monitoring unit 56 consists of a plurality of microprocessors or at least partially of discrete components with appropriate transistor logic. In addition, the monitoring unit 56 can have a memory for storing at least one operating parameter of the replaceable battery pack 12, such as the battery voltage Ußatt, the cell voltages Uceii, the charging or discharging current I, a current integral, a temperature T or the like.

A temperature sensor 66, which is arranged in the replaceable battery pack 12 and is preferably embodied as an NTC and is in close thermal contact with at least one of the energy storage cells 46, is used to measure the temperature T of the replaceable battery pack 12 or the energy storage cells 46 using a measuring circuit 64 integrated in the replaceable battery pack 12. The temperature T measured in this way can then be evaluated by a control or regulating unit 68 of the interface module 34 via a first contact 14 of the electromechanical interfaces 16 , 22 embodied as a signal or data contact 70 . So that the interface module 34 of the electrical consumer 20 can identify the replaceable battery pack 12 and, if necessary, release it for discharging, the replaceable battery pack 12 has a coding resistor 72 which is connected to the measuring circuit 62 . The resistance value of the coding resistor 72 measured with the measuring circuit 62 can then be evaluated by the control or regulating unit 68 of the interface module 34 via a further contact 14 embodied as a signal or data contact 74 of the electromechanical interfaces 16 , 22 . If the resistance value of the coding resistor 72 matches an expected value stored in a memory of the control or regulation unit 68 of the interface module 34 , then the discharging process of the replaceable battery pack 12 is released by the control or regulation unit 68 of the interface module 34 . Instead of just one coding resistor 72, several coding resistors can also be provided in the replaceable battery pack 12 for the charging and discharging process. If the measured resistance values of the coding resistors do not match the expected values according to the look-up table, the charging or discharging process of the exchangeable battery pack 12 is interrupted or not permitted. This particularly advantageously allows the operation of exchangeable battery packs 12 of different performance classes with identical electromechanical interfaces 16 and 22.

In addition to the measured temperature T or the resistance value of the temperature sensor 66 and/or the coding resistor 72, the other operating parameters already mentioned can also be transmitted via the first and/or second signal or data contact 70 or 74 from the replaceable battery pack 12 to the interface module 34 for evaluation there be transmitted by means of the control or regulation unit 68. In addition, the signal or data contacts 70 or 74 can also be bidirectional for the mutual exchange of information between the replaceable battery pack 12 and the electrical load 20 . In this way, interface module 44 can control replaceable battery pack 12 via monitoring unit 56 located there or, if necessary, also directly if the at least one operating parameter exceeds or falls below a limit value stored in the memory of control or regulating unit 68 of interface module 34 and/or from a expected value stored in the memory. In this case, for example, a shunt resistor 76 of the interface module 34 is used to measure the discharge current I. In addition, the interface module 34 can have a temperature sensor, not shown, for measuring the temperature T. A direct measurement of the battery voltage U.sub.Batt present at the energy supply contacts 42, 44 of the interface module 34 by means of the control and regulation unit 68 is also conceivable. The limit value can consequently be a minimum or maximum permissible voltage value, a minimum or maximum permissible current value or a maximum permissible temperature value and the expected value can be a current-time profile, a resistance value of the temperature resistor 66 or the coding resistor 72, another identification value of the replaceable battery pack 12 or a Information about an interruption in the connection to the temperature resistor 66 or to the coding resistor 72 be. It is also conceivable that the signal or data transmission takes place via the first and/or the second energy supply contact 42, 44 in the sense of a power line communication instead of via the additional signal or data contacts 70, 74.

If the discharge current I measured by means of the shunt resistor 76 exceeds a maximum permissible current value, for example, or if the battery voltage Ußatt measured by the control or regulating unit 68 of the interface module 34 is outside the voltage class of the electrical consumer 20, i.e. below a minimum permissible or above a maximum permissible voltage value, the discharge current I from the replaceable battery pack 12 to the electrical load 20 can be temporarily or permanently interrupted by the control or regulating unit 68 of the interface module 34 opening a switching element 78 in the ground path (low side) of the interface module 34. However, it is also conceivable for one or more switching elements 78 to be arranged in the supply path (high side). Likewise, at least one switching element 78 can be provided both in the supply path and in the ground path. Switching element 78 is preferably designed as a MOSFET, with other switching elements such as a relay, an IGBT, a bipolar transistor or the like also being conceivable. Thus, using the interface module 34, electrical consumers 20 and/or exchangeable energy stores 10 can also be operated safely, which themselves do not have an integrated option for interrupting the energy supply. As shown in FIG. 2, the exchangeable battery pack 12 itself can also have a corresponding switching element 80 for interrupting the discharging or charging current I, which is controlled by means of the monitoring unit 56 located there. This then receives via the at least one designed as a signal or data contact 70, 72 contact 14 of the electromechanical Interfaces 16, 20 of the replaceable battery pack 12 and the interface module 34 see a corresponding switching command from the control or regulation unit 68 of the interface module 68. To adapt the signals or data transmitted via the signal or data contacts 70, 72 between the monitoring unit 56 or the measuring circuit 62 of the replaceable battery pack 12 and the control or regulation unit 68 of the interface module 34, the interface module 34 has corresponding analog or analog-to-digital converters 82, each of which is located between the signal or data contacts 70, 72 and the control or regulation unit 68 are switched.

To control or regulate the electrical consumer 20, the control or regulation unit 68 of the interface module 34 is connected to an electronic unit 86 of the electrical consumer 20 via a further interface 84. For this purpose, the further interface 84 has contact points 88 which are designed, for example, as soldering or plug-in contacts of the interface module 34 designed as a printed circuit board. A first of these contact points 88 serves as a particularly bidirectional data contact 90 and a second contact point 88 as a release contact 92 between electronics unit 86 and a protection circuit 94 of interface module 34. Protection circuit 94 adjusts the level of any voltage differences between electronics unit 86 of electrical load 20 and the control or regulating unit 68 of the interface module 34. To this end, it separates the corresponding signals from one another via two different ground potentials. These two ground potentials can also be electrically isolated from one another. While a first ground potential is at the ground potential GND of the exchangeable battery pack 12 , the second ground potential is defined via the electrical load 20 . The control or regulating unit 68 of the interface module 34 can optionally send a wake-up signal to the electronics unit 86 of the electrical consumer 20 via a third contact point 88 of the interface 84 configured as a wake-up contact 96 if the electronics unit 86 cannot be woken up directly via the enable contact 92. The outputs of the protective circuit 94 connected to the enabling contact 92 or the wake-up contact 96 are preferably designed as open collector outputs which draw the respective collector to the second ground potential of the electrical load 20 when the associated transistor is closed. In order to put the electrical load 20 into operation, the operator actuates a main switch 98 of the electrical load 20 (cf. also FIG. 1 in this regard). This wakes up the control or regulating unit 68 of the interface module 34 via a wake-up sleep detection circuit 100 connected to the main switch 98 by means of a fourth contact point 88 of the interface 84 . The control or regulating unit 68 then closes the previously open switching element 78 of the interface module 34 in order to enable the power supply from the exchangeable battery pack 12 to the electrical consumer 20 . The waking up of the control and regulation unit 68 of the interface module 34 also wakes up the electronics unit 86 of the electrical load 20 via the enable contact 92 or the wake-up contact 96 . This is particularly useful if the electronics unit 86 of the electrical load 20 is to be woken up by plugging in the replaceable battery pack 12 in order to achieve a particularly quick response to the operation of the main switch 98 .

Electronics unit 86 then queries the at least one operating parameter recorded by interface module 34, or interface module 34 in turn sends the at least one recorded operating parameter to electronics unit 86. If the at least one recorded operating parameter is within those stored in the memory of control or regulating unit 68 of interface module 34 limit values or if it meets an expected value stored there, the electronics unit 86 of the electrical load 20 switches on an electrical load 102 which is connected to the first and the second energy supply contact 42, 44 of the electromechanical interface 22 of the interface module 34 and to which the battery voltage Ußatt is present . The electrical load 102 can be configured, for example, as a brushless direct current motor (EC or BLDC motor, not shown) of the cordless vacuum cleaner 24, the cordless impact wrench 26 or the cordless lawn trimmer 28, which is controlled by means of a power output stage 104 via pulse width modulation (PWM). A detailed description of these devices will be dispensed with since they are well known to those skilled in the art and are therefore not essential to the invention. A B6 bridge or the like can be considered as the power output stage 104 , which drives a three-phase BLDC motor to change its speed and/or torque with pulse width modulation, which has a direct influence on the discharge current I of the replaceable battery pack 12 . The power output stage 104 generally has a load capacitance 108 embodied as an intermediate circuit capacitance 106 . the invention However, the application is neither limited to loads 102 driven by electric motors in general nor to BLDC motors controlled by power output stage 104 in particular. Thus, the electrical load 102 can also have an electric motor with brushes or be designed as a non-motor. Numerous variants of possible electrical loads are known to a person skilled in the art, so that there is no need to go into further detail here.

In the event that electrical load 20 itself does not have an electronics unit 86, it can alternatively also be provided that control or regulation unit 68 of interface module 34 switches on electrical load 102 in electrical load 20 if the at least one operating parameter recorded in the The expected value stored in the memory of the control or regulation unit 68 is met and/or is within stored limit values.

In order to protect the operator from injury immediately after connecting the replaceable battery pack 12 to an electrical load 20 that is accidentally still switched on, the control or regulating unit 68 of the interface module 34 can use a start-up protection circuit 110, depending on the state of charge of the load capacitance 108, to provide start-up protection via the electronic unit 86 of the electrical load 20 cause. Additionally or alternatively, the start-up protection circuit 110 can also be used to prevent the interface module 34 from being automatically reset. In this way it can be ensured that an energy supply interrupted by the switching element 78 of the interface module 34 as a result of a detected error condition after the error condition has been eliminated, for example because the temperature T or a fault current of the replaceable battery pack 12 has fallen below the respective limit value again, by automatic closing of the switching element 78 is restored.

In order to also protect the switching element 78 of the interface module 34 from an excessively high discharge current I immediately after the operator has switched on the electrical load 20, the switching element 78 is only switched on permanently when the state of charge of the load capacitance 108 of the electrical load 20 is on a defined threshold value, for example 90%, has increased. For this purpose, the control or regulation unit 68 of the interface module 34 controls the at least one switching element 78 after actuation ment of the main switch 98 until the defined threshold value for the state of charge is reached. Alternatively or additionally, a specially configured charging stage 112 can also be provided in the interface module 34 for clocked or non-clocked precharging of the load capacitance 108 .

A further protective measure results from the fact that the energy supply is interrupted by the opening of the switching element 78 if the discharge current I has not dropped to approximately zero a defined period of time _T off after the electrical load 20 has been switched off. In this way, any fault currents can be detected.

Provision is also made for the interface module 34 to be supplied with energy for a follow-up time T _post , in particular between 5 and 15 minutes, after the main switch 98 has been released, before the control or regulating unit 68 of the interface module 34 switches the at least one switching element 78 to the Interruption of the power supply to the electrical load 20 opens. This ensures, on the one hand, a very quick restart within the run-on time T _post and, on the other hand, reliable monitoring of the operating parameters even after the electrical consumer 20 has been switched off.

In order to indicate to the operator any error states detected by interface module 34 and/or an interruption in the power supply to electrical load 20, interface module 34 has an LED 112, which is preferably located at a location on electromechanical interface 22 of the interface module that is clearly visible from the outside 34 is provided. However, other optical, acoustic and/or haptic display means are also suitable for the display, such as an HMI (Human Machine Interface) in the form of an LC, LED, OLED, AMOLED display or the like, a dynamic loudspeaker or piezo and/or or a small vibration motor. It is also conceivable that display means already contained in the electrical load 20 are used, which can be controlled via the control and regulation unit 68 of the interface module 34 and the electronics unit 86 of the electrical load 20 . Provision can also be made for the display means of the interface module 34 to be used to display operating and/or error states of the electrical load 20 . This makes sense in particular when the electrical consumer itself does not have a corresponding display device. Figure 3 shows a section through the base 114 of the electrical load 20 designed as a drill impact driver 26. The interface module 34 together with the associated electromechanical interface 22 is accommodated in a half-shell 116 of the base 114 in such a way that the removable battery pack 12 (not shown) with its electromechanical interface 16 can be connected directly can be inserted into the foot 114 and then locked there with its locking member 40 in a not shown depression of the electromechanical interface 22 of the interface module 34 shown only schematically. The interface module 34 is designed as a cast circuit board 118 which is electrically connected to the electronics unit 86 of the impact drill 26 via the interface 84 . The power output stage 104 as part of the electrical load 102 is only indicated in outline. However, the structure of the impact drill 26 is known to a person skilled in the art, so that it will not be discussed further at this point.

So that the interface module 34 can be used flexibly and universally for a wide variety of electrical consumers 20, it is configured in FIG. 4 as an adapter 120 that can be changed without tools. The adapter 120 has at least two different electromechanical interfaces 22, 122, the first electromechanical interface 22 being compatible with the electromechanical interface 16 of the replaceable battery pack 12 and the at least one second electromechanical interface 122 being compatible with an electromechanical interface 124 of the electrical load embodied as a rotary hammer 126 20 is. For this purpose, the at least one second electromechanical interface 122 has the electrical contact points 88 of the interface 84 . A particularly high level of flexibility can be achieved if the at least one second electromechanical interface 122 of the adapter 120 is designed to be exchangeable on the adapter 120 for different electrical loads 20 . Here, however, it makes sense that the at least one second electromechanical interface 122 can only be replaced by the manufacturer. It is also conceivable that the entire adapter 120 can only be replaced by the manufacturer of the electrical consumer 20 using the appropriate tool. Compared to the interface module 34 designed as a cast printed circuit board 118, this results in the additional advantage that the interface module 34 can be more easily replaced by the manufacturer of the electrical load 20. The electrical load 20 can also be replaced more quickly in this way back to its original electromechanical interface 124.

FIG. 4 also shows the possibility of configuring the adapter 120 in such a way that it has two first electromechanical interfaces 22 for two parallel or series-connected exchangeable battery packs 12 each with the same battery voltage Ußatt for particularly powerful electrical consumers 20 of a defined voltage class. In the case of a parallel connection of the two exchangeable battery packs 12, the voltage class of the electrical load 20 must then correspond to the respective battery voltage Ußatt of a single exchangeable battery pack 12, while the voltage class of the electrical load 20 in a series connection of the two exchangeable battery packs 12 must be twice as high as the battery voltage Ußatt a single exchangeable battery pack 12. Accordingly, electronics must then also be provided in the adapter 120 or in the interface module 34, which is suitable for managing the two exchangeable battery packs 12. In addition, the electronics are advantageously able to compensate for certain voltage deviations between the resulting battery voltage Ußatt of the connected exchangeable battery packs 12 and the defined voltage class of the electrical load 20 . However, since such electronics are known to those skilled in the art, they will not be discussed in any more detail.

In order to indicate to the operator any error states detected by interface module 34 of adapter 120 and/or an interruption in the power supply to electrical load 20, adapter 120 has an optical, acoustic, and/or haptic indicator 128, which is the same as that already mentioned above LED 112 or another suitable HMI can be formed. Here, too, the display means 128 of the adapter 120 can also be used to display operating and/or error states of the rotary hammer 126, particularly if the latter does not have its own corresponding display means.

FIGS. 5 and 6 show two possible configurations of the electromechanical interface 22 of the interface module 34 or of the adapter 120 for tool-free connection to various exchangeable battery packs 12 for two different battery voltages Ußatt or voltage classes. In Figure 5 is the electromechanical interface 22 is designed, for example, for a battery voltage Ußatt of 18 V and in FIG. 6 for a battery voltage Ußatt of 10.8 V.

The electromechanical interfaces 22 each have the electrical contacts 14 shown in FIG second reference potential V2, preferably ground potential GND, power supply contact 44 that can be acted upon, and a third and fourth of the electrical contacts 14 each serve as a signal or data contact 70 or 74, respectively. The electrical contacts 14 are attached to a contact carrier 130, which is preferably made of plastic, or is partially encapsulated by it. In addition, the contact carrier 130 has mechanical codings 132, so that the electromechanical interface 22 is only compatible with replaceable battery packs 12 of a specific voltage and/or power class.

In contrast to the contact holder 130 shown in Figure 6, the contact holder 130 shown in Figure 5 is resiliently mounted on the interface module 34 or adapter 120 via a compression spring 134, so that the electromechanical interface 22 is better protected against vibrations during the operation of the electrical load 20 . This is particularly advantageous in particular in the case of electrical consumers 20 in higher power classes.

Analogously to the electromechanical interface 22, the second electromechanical interface 122 of the adapter 120 indicated in FIG. However, its structure depends significantly on the configuration of the electromechanical interface 124 of the electrical load 20 .

Finally, it should also be pointed out that the invention is neither limited to the forms and proportions of the exemplary embodiments shown in FIGS. 1 to 6 nor to the values and numerical data given as examples in the description.

Claims

- 25 - claims

1. Interface module (34) for operating an electrical load (20) of a defined voltage class with at least one exchangeable energy store (10) that is directly incompatible with the electrical load (20), characterized in that the defined voltage class of the electrical load (20) has a corresponds to integer multiples of a battery voltage (Ubatt) of the at least one exchangeable energy store (10) and that the interface module (34) has a control or regulating unit (68) which has at least one operating parameter (U, I, T) of the exchangeable energy store (10) monitored and depending on the monitored operating parameters (U, I, T) controls an electrical load (102) of the electrical consumer (20).

2. Interface module (34) according to claim 1, characterized in that the interface module (34) has an interface (84) to the electrical load (20) via which the exchangeable energy store (10) and the electrical load (20) information, in particular can send and/or receive via the at least one operating parameter (U, I, T).

3. Interface module (34) according to any one of the preceding claims, characterized in that the at least one operating parameter (U, I, T) is a voltage (U), a current (I), a current integral, a temperature (T), information via a temperature resistor (66) and/or information about a coding resistor (72) or other values for identifying the exchangeable energy store (10).

4. Interface module (34) according to one of the preceding claims, characterized in that the interface module (34) has at least one switching element (78), in particular at least one MOSFET, by means of which the control or regulating unit (68) controls the energy supply from the exchangeable energy store (10) to the electrical consumer (20) can be interrupted temporarily or permanently if the at least one operating parameter meter (U, I, T) exceeds or falls below a limit value stored in a memory of the control or regulation unit (68) and/or deviates from an expected value stored in the memory. Interface module (34) according to Claim 4, characterized in that the limit value is a minimum or maximum permissible voltage, a minimum or maximum permissible current or a maximum permissible temperature and the expected value is a resistance value of the temperature resistor (66) or the coding resistor (72) or information about an interruption in the connection to the temperature resistor (66) or to the coding resistor (72) is formed. Interface module (34) according to one of the preceding claims 4 or 5, characterized in that the control or regulating unit (68) depending on the state of charge of a load capacitance (106) of the electrical load (102), in particular an intermediate circuit capacitance (108) of a power output stage ( 104), the electrical load (20) causes a start-up protection of the electrical load (20) when power is supplied again by the switching element (78) after an interruption and/or prevents the interface module (34) from being automatically reset. Interface module (34) according to Claim 6, characterized in that the control or regulating unit (68) controls the at least one switching element (78) in a clocked manner in order to precharge the load capacitance (106) of the electrical consumer (20) before it is put into operation. Interface module (34) according to one of the preceding claims, characterized in that the interface (84) of the interface module (34) has a release contact (92) and/or wake-up contact (96) designed as an open collector output for sending a wake-up signal to an electronic unit (86) of the electrical load (20). Interface module (34) according to one of the preceding claims, characterized in that the interface module (34) has a display means (112, 128) for displaying a detected fault condition and/or an interruption in the power supply to the electrical consumer (20). Interface module (34) according to one of the preceding claims, characterized in that the interface module (34) has an electromechanical interface (22) which is compatible with an electromechanical interface (16) of the exchangeable energy store (10). Interface module (34) according to one of the preceding claims 2 to 10, characterized in that the interface module (34) is designed as an exchangeable adapter (120) for the electrical load (20), the adapter (120) having a first, for electromechanical Interface (16) of the exchangeable energy store (10) compatible, electromechanical interface (22) and a second, to an electromechanical interface (124) of the electrical load (20) compatible, electromechanical interface (122), which includes the interface (84). . Method for controlling an electrical consumer (20) by means of an interface module (34) according to one of the preceding claims, having at least the following steps:

• Actuating a main switch (98) of the electrical consumer (20) to wake up a control or regulating unit (68) of the interface module (34),

• switching on at least one switching element (78), in particular at least one MOSFET, of the interface module (34) for supplying energy from at least one exchangeable energy store (10) connected to the electrical load (20) to the electrical load (20) and

• Switching on an electrical load (102) of the electrical consumer (20) when the at least one detected operating parameter (U, I, T) meets an expected value stored in a memory of the control or regulation unit (68) of the interface module (34) and/ or is within stored limit values. Method according to Claim 12, characterized by the further steps after switching on the at least one switching element (78):

• waking up an electronic unit (86) of the electrical consumer (20),

• Queries at least one operating parameter (U, I, T) recorded in the interface module (34) by the electronic unit (86) of the electrical connection - 28 - consumer (20) or sending the at least one operating parameter (U, I, T) recorded in the interface module (34) to the electronics unit (86) of the electrical consumer (20) and

• Switching on the electrical load (102) of the electrical consumer (20) by the electronics unit (86) of the electrical consumer (20) when the at least one recorded operating parameter (U, I, T) has a value stored in the memory of the control or regulation unit ( 68) of the interface module (34) and/or is within stored limit values. Method according to one of the preceding claims 12 or 13, characterized in that in one step a load capacitance (106) of the electrical load (102), in particular an intermediate circuit capacitance (108) of a power output stage (104), of the electrical consumer (20) before the permanent Closing the switching element (78) is charged. Method according to one of the preceding claims 12 to 14, characterized in that in one step the energy supply from the energy store (10) to the electrical consumer (20) is interrupted by opening the at least one switching element (78) and/or that the interface module (34) sends a switch-off command via a release contact (92) designed as an open collector output to the electronic unit (86) of the electrical consumer (20) as soon as the at least one recorded operating parameter (U, I, T) exceeds the value in the memory of the control or regulation unit (68) of the interface module (34) is not met and/or is outside the stored limit values. Method according to one of the preceding claims 12 to 15, characterized in that in one step the at least one switching element (78) is opened to interrupt the energy supply if the discharge current (I) a defined period of time (T _O ff) after switching off the electrical consumer (20) has not fallen anywhere near to zero. Method according to one of the preceding claims 12 to 16, characterized in that after the main switch (98) is released, the interface module (34) supplies energy in one step for a run-on time (T _pos t), in particular between 5 and 15 minutes is before the control or regulation unit (68) of the interface module (34) that at least - 29 - a switching element (78) to interrupt the power supply to the electrical consumer (20) opens.