Hilti Aktiengesellschaft

Michael Lacher

Stefan Ringler

Christian Sattler

Jerome Jaromin

Manel Ouni

Roland Schwab

A power tool is provided having a motor and a motor shaft, wherein a fan wheel in the power tool is designed to generate an air flow for cooling the motor. The power tool provides a coupling formed magnetically between the fan wheel and the motor shaft such that the motor shaft drives the fan wheel in a rotary movement with a speed that is less than a speed of the motor shaft. As a result of the magnetic coupling of the fan wheel and motor shaft, the movements of the two components can be decoupled from one another such that an increase in the rotational speed of the motor shaft does not also result in an increased speed at the fan wheel. As a result, fan losses can be considerably reduced and the efficiency of the motor of the power tool can be significantly improved. A method is also provided for cooling a motor of a power tool, wherein there is a magnetic coupling between a fan wheel and a motor shaft of the power tool.

Magnetic coupling between power tool motor shaft and fan wheel

Methods for activating and deactivating a spindle lock in a power tool, wherein the spindle lock can be activated, for example, by an intuitive movement by the user. In particular, the spindle lock can be activated by a rotary movement of the user on the tool fitting, which is recognized by the device electronics of the power tool. Exceeding a limit value for an angle of rotation or a rotational speed can be used by the device electronics as an activation signal for the spindle lock. The spindle lock can be deactivated if the device electronics detect a rotary movement of the tool fitting in the opposite direction. In further aspects, the invention relates to a power tool with which the methods for activating and deactivating a spindle lock can be carried out.

Method for activating and deactivating a spindle lock in a power tool, and power tool

A power tool having a first accumulator and a second accumulator, wherein the power tool has a first power electronics system with a first inverter and a second power electronics system with a second inverter, wherein the first inverter is electrically connected to the first accumulator and the second inverter is electrically connected to the second accumulator. The first power electronics system includes a first charge equalization device while the second power electronics system includes a second charge equalization device. The charge equalization devices are configured to carry out charge equalization between the accumulators. Furthermore, the power tool includes a device for speed control. In a second aspect, the invention relates to a method for carrying out charge equalization between two accumulators in a power tool. In this case, the charge equalization is preferably carried out by different load splitting via the charge equalization devices of the power electronics systems.

Power tool and method for carrying out charge equalization between accumulators in a power tool

An apparatus for supplying a power tool with electrical energy is provided. The apparatus can be used, for example, to connect the power tool to an energy network so that it can perform the function of a mains adapter. The apparatus includes a first component for converting an AC voltage into a DC voltage, as well as a second component which is configured to convert the DC voltage generated by the first component into a device DC voltage. In a second aspect, the invention relates to a system which includes a apparatus and a power tool, wherein the power tool can be supplied with electrical energy using the apparatus. A use of the apparatus for supplying a power tool with electrical energy. Advantageously, particularly high power densities can be achieved with the invention and powers of more than 1700 watts can be provided.

Apparatus and system for supplying a power tool with electrical energy, and use of the apparatus for this purpose

A device for supplying a power tool with electrical energy is provided. The device has a load resistor for absorbing electrical energy, which may be in particular electrical energy that is produced or released when a power tool or its tool is braked. In addition, the released braking energy can be converted into heat by the load resistor. A system which includes a device and a power tool, a load resistor of the device being set up to absorb electrical energy that is released during a braking process of the power tool. The released braking energy can be converted into heat by the load resistor. The use of a load resistor for absorbing such electrical energy released during a braking process of a power tool or for converting the braking energy into thermal energy, as well as an operating method for a system which includes a energy supply device and a power tool.

Device for supplying a power tool with electrical energy, as well as the use of a load resistor for absorbing and/or converting electrical energy, system and operating method

Growing community of inventors

Schwabmuenchen, Germany

Michael Lacher