Device for locking an electric tool with a rechargeable battery pack

1. A device for locking an electric tool with a rechargeable battery pack, comprising at least one locking bar mounted an one element selected from the group consisting of the electric tool and the rechargeable battery pack in a manner that allows it to move against a spring force, whereby when the electric tool and the rechargeable battery pack are joined, said looking bar is engaged in succession in a first and a second recess of the other element selected from the group consisting of the electric tool and the rechargeable battery pack, and is retained tightly in said second recess by a force of a spring and, to release a lock, is manually disengaged from said second recess, wherein said locking bar is engaged in said first recess while being disengaged from said second recess, and wherein during engagement of said locking bar in said first recess, said rechargeable battery pack is retained against unintended disengagement from the electric tool.

2. A device as defined in claim 1 , wherein said locking bar and said recesses are configured so that, when the rechargeable battery pack is being detached from the electric tool, said locking bar is disengaged from said first recess by the force of said spring.

3. A device as defined in claim 1 , wherein said locking bar and said recesses are formed so that when the electric tool and rechargeable battery pack are joined, said locking bar is automatically engaged in said first recess against the force of said spring.

4. A device as defined in claim 3 , wherein said locking bar has a slanted edge that interacts with another slanted edge when the electric tool and rechargeable battery pack are joined, to move the locking bar into said first recess.

5. A device as defined in claim 1 , wherein said first recess is larger than said second recess.

6. A device as defined in claim 1 , wherein said locking bar is movable transversely to a direction of motion during joining and engages in said first or second recess with diametrically opposite ends.

7. A device as defined in claim 1 , wherein said locking bar is pivotable and has two arms that engage with said first or second recess when said locking bar is swiveled.

8. A device as defined in claim 1 ; and further comprising another locking bar, said locking bars being located in succession in said one element selected from group consisting of the electric tool and the rechargeable battery pack and engage in said recesses in diametrically opposed surfaces of the other element selected from the group consisting of the electric tool and the rechargeable battery pack.

9. An electric tool system, comprising an electric tool; a rechargeable battery pack; and a device for locking said electric tool with said rechargeable battery pack, said locking device including at least one locking bar mounted on one element selected from the group consisting of the electric tool and the rechargeable battery pack in a manner that allows it to move against a spring force, whereby when the electric tool and the rechargeable battery pack are joined, said locking bar is engaged in succession in a first and a second recess of the other element selected from the group consisting of the electric tool and the rechargeable battery pack, and is retained tightly in said second recess by a force of a spring and, to release a lock, is manually disengaged from said second recess, wherein said locking bar is engaged in said first recess while being disengaged from said second recess, and wherein during engagement of said locking bar in said first recess, said rechargeable battery pack is retained against unintended disengagement from the electric tool.

10. An electric tool system as defined in claim 9 , wherein said locking bar is provided in said electric tool while said recesses are provided in said rechargeable battery pack.