The invention relates to a battery pack for an electrical device and to an electrical device, in particular a handheld power tool, as defined generically by the preambles to independent claims 1 and 8.
There are numerous electric tools that are equipped with replaceable battery packs for supplying power to them. The battery packs are usually designed especially for a specific electric tool. Other battery packs, not intended for the electric tool, for instance with a different rated voltage, must not be used for the electric tool, so that the battery pack and/or the electric tool will not become damaged. To ensure the association of the proper battery pack with an electric tool, it is known to use mechanical coding systems, which allow the battery pack to be inserted and electrically contacted only whenever the battery pack has a code that corresponds with the counterpart code of the electric tool. In German Patent Disclosure DE 10 2005 008 036 A1, for instance, an insertable battery pack for an electric tool is described that has a mechanical coding system, and the code has at least one indentation cooperating on opposed sides with at least one protrusion forming the counterpart code on the tool.
Especially whenever a plurality of different battery packs for different electrical devices are available, when a battery pack is replaced it must reliably be prevented that the wrong battery pack be assigned to the electric tool. A secure and essentially tamperproof coding system is therefore necessary.
The invention is based on a battery pack for an electrical device, in particular for a handheld power tool, which has means for mechanical coding for cooperation with corresponding coding means on an electrical device.
According to the invention, the coding means are disposed relative to one another, with respect to a first axis in the insertion direction, a second axis transverse to the insertion direction, and a third axis transverse to the insertion direction and transverse to the second axis, in such a way that they form a three-dimensional coding system, A three-dimensional coding system is understood to be a coding system whose coding means are operative in all three coordinate axes with respect to the insertion direction. The three-dimensional code results not only from the three-dimensional shape of the coding means but also from the spatial disposition of the coding means relative to one another. This makes an even greater number of combinations of coding means possible, even if the coding means have the same three-dimensional shape. The three-dimensional coding system according to the invention reliably makes it possible to prevent mistakes in manipulation, or in other words associating the wrong battery packs with an electrical device. The coding means and counterpart coding means must fit one another not only dimensionally but also in their spatial disposition. If a coding means does not correspond precisely with a counterpart coding means dimensionally and/or in its spatial disposition, then the battery pack and the electrical device cannot be connected to one another. It is thus ensured that only the correct battery packs are associated with an electrical device.
Within the scope of the present invention, the first axis is defined as the axis which extends parallel to the insertion direction. The second axis is formed by the axis that extends in a first direction transverse to the insertion direction, while the third axis is the axis which extends transversely both to the insertion direction and to the second axis. The spatial orientation of the three axes, which are at a right angle from one another, depends on the insertion direction of the battery pack. The battery pack may for instance be intended for being mounted on the lower free end of the handle of a handheld power tool, so as to form a base for the tool to stand on. In that case, the insertion direction is located in the horizontal direction, so that the first axis in the insertion direction, as well as the second axis transverse to the insertion direction, are horizontal axes, while the third axis transverse to the insertion direction is a vertical axis. However, there are also battery packs which for example are introduced into the handle in the vertical direction on the lower free end of the handle. In that case, the insertion direction is in the vertical direction. The second axis transverse to the insertion direction and the third axis transverse to the insertion direction are conversely horizontal axes. In principle, a battery pack can also be inserted at an arbitrary angle relative to a handheld power tool. In a further alternative, the battery pack can also be mounted on the handheld power tool by a pivoting motion. In such a battery pack, a three-dimensional coding system can also be used, and an insertion direction can be defined accordingly.
The coding means are preferably disposed in the vicinity of the interface between the battery pack and the electrical device. Electrical contact elements for the power supply and optionally further contact elements, for instance for data exchange, are present in the vicinity of the interface as well. A locking device, with which the battery pack can be connected detachably but securely to the electrical device, can also be disposed in the vicinity of the interface.
Coding along the first axis in the insertion direction is effected for instance by disposing two coding means offset from one another in the insertion direction. The coding means on a battery pack may for instance be coding ribs. The counterpart coding means on a handheld power tool are accordingly formed by corresponding coding ribs. For instance, if two coding ribs in the first axis are offset from one another, then the corresponding coding ribs along the first axis are embodied with different lengths. An offset of the coding means in the first axis can be combined for example with an offset in the second axis, so that the coding means are not aligned with one another in the insertion direction, but are offset both longitudinally of one another and laterally.
Coding along the second axis transverse to the insertion direction is effected for instance by disposing two coding means offset from one another transverse to the insertion direction. In addition, the coding means offset from one another transversely to the insertion direction in the second axis may be identical or different. For instance, they can have a different length along the second axis. Thus the coding means may for instance be coding ribs, which are of the same length or different lengths along the second axis. The counterpart coding means must accordingly have corresponding coding ribs of identical or different lengths along the third axis.
Coding along the third axis transverse to the insertion direction and transverse to the second axis is effected for instance by disposing two coding means offset from one another in the third axis. This can be done for instance by providing that the coding means in the third axis have a different length. In a battery pack with a horizontal insertion direction, the third axis is oriented vertically, so that the coding means have a different vertical length.
Alternatively, the coding means in the third axis may be offset from one another, in that the coding means are disposed in at least two different coding planes. A coding plane is defined by two of the three axes. For instance, in a battery pack with a horizontal insertion direction, the first and second axes define a horizontal coding plane. In the coding plane, the coding means are disposed such that they form a three-dimensional coding system. To enable disposing the coding means offset from one another in the third axis as well, two or more parallel coding planes are preferably provided. In a battery pack with a horizontal insertion direction, two horizontal, parallel coding planes can be disposed longitudinally of one another with a vertical offset, for instance in the insertion direction. The two horizontal, parallel coding planes can also be disposed such that they are offset laterally and vertically transversely to the insertion direction. Analogously, in a battery pack with a vertical insertion direction, two vertical, parallel coding planes can be provided longitudinally of one another in the insertion direction or laterally and with a horizontal offset. It is moreover possible to provide more than two coding planes, which can be offset from one another longitudinally and/or laterally in the insertion direction. A three-dimensional coding system with two or more coding planes considerably increases the number of possible combinations of coding means. Combining a battery pack with an electrical device for which the battery pack is not intended can thus be prevented all the more securely. In particular, coding planes that are parallel to one another but offset from one another have the advantage that the three-dimensional coding system can be accommodated in the smallest possible space yet with a great many possible coding options.
Instead of two or more parallel coding planes, two or more coding planes can be at a right angle to one another. For instance, in a battery pack with a horizontal insertion direction, one horizontal and one vertical coding plane may be provided, and the horizontal coding plane is defined by the first and second axes, while the vertical coding plane is defined by the first and third axes. The coding planes disposed perpendicular to one another can thus be equipped with coding means in such a way that a three-dimensional coding system is formed. Coding planes disposed perpendicular to one another can be used for instance in battery packs with a vertical insertion direction, since then as a rule, despite the compactness of the battery packs and of the electrical devices, there is more space available for the coding means in the vicinity of the interface.
The three-dimensional coding system includes at least two coding means. If there are only two coding means, then they are offset from one another with respect to the first axis, second axis, and third axis, in order to form a three-dimensional coding system. These two coding means may for instance be coding ribs, which are offset from one another in the first and second axes and as a result are offset from one another in the third axis because they have a different length along the third axis. The two coding means may, however, also have the same length along the third axis but be disposed in different coding planes.
If the three-dimensional coding system includes at least three coding means, then two coding means may also be offset from one another with respect to only two of the three axes, if the three coding means overall are offset from one another in all three planes; that is, all combinations of two coding means at a time must result in an offset of the coding means in all three axes.
The more coding means are used, the higher is the number of possible combinations of coding means. Combining a battery pack with an electrical device that is not suitable for the electrical device can thus be effectively prevented. The more complex the three-dimensional coding system is, the less is the risk that the coding system can be tampered with by improper handling, for instance by removing or bypassing coding ribs.
The coding means on the counterpart coding means themselves have a three-dimensional shape. The coding means are in particular coding ribs. The counterpart coding means are accordingly formed by corresponding coding ribs. The coding ribs can also have rounded edges or corners, or instead of a polygonal cross section, they may generally have a round or other kind of cross section. The coding ribs may be provided on the battery pack, while a battery-operated electrical device has corresponding coding ribs as its counterpart coding means. On the other hand, naturally the electrical device, in particular the handheld power tool, may be provided with coding ribs that cooperate with corresponding coding ribs on a battery pack.
A battery-operated electrical device, in particular a handheld power tool, forms a further subject of the invention. The electrical device is suitable for being connected to the battery pack of the invention. To that end, the electrical device has means for mechanical coding which form a coding system that is compatible with the coding system of the battery pack of the invention. The coding means of the electrical device are disposed relative to one another with respect to a first axis in the insertion direction, a second axis transverse to the insertion direction, and a third axis transverse to the insertion direction, such that they form a three-dimensional coding system.
The invention is described in further detail below in conjunction with the accompanying drawings.
The three-dimensional coding system 20 is disposed in the vicinity of the interface 12 between the battery pack 10 and the handheld power tool. Electrical contact elements 13 for the power supply are also present in the vicinity of the interface 12. A locking device 14 with a bolt, with which the battery pack 10 can be connected detachably but securely to a handheld power tool, is also disposed in the vicinity of the interface 12. The battery pack 10 is moreover equipped with guide means 15, in the form of guide grooves. The guide means 15 facilitate the correct introduction of the battery pack 10 into the battery pack receptacle of a handheld power tool. As can be seen from
The coding means 23, 24, 25, 26, in the embodiment shown in
The coding means 23, 24, 25, 26 are disposed relative to one another, with respect to a first axis 1, which extends parallel to the insertion direction, a second axis 2, which extends in a first direction transverse to the insertion direction, and a third axis 3, which extends in a second direction transverse to the insertion direction and transverse to the second axis 2, in such a manner that they form a three-dimensional coding system 20. In
The three-dimensional coding system 20 of
An interface 42 of a handheld power tool, corresponding to the interface 12 of the battery pack 10, is shown in perspective in
In
Number | Date | Country | Kind |
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10 2007 044 501.8 | Sep 2007 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP08/59867 | 7/28/2008 | WO | 00 | 3/15/2010 |