Abstract: The invention relates to a regulator circuit for controlling the power fed to an electric motor from a voltage source, wherein the regulator circuit comprises a semiconductor switching element connected in series to the electric motor and the voltage source for the purpose of controlling the power fed to the electric motor, a control circuit for controlling the semiconductor switching element, and a first operating element for operating the control circuit by means of an operating signal generated by the operating element and fed to the control circuit, wherein a microprocessor is incorporated in the control circuit. The microprocessor can be adapted to control numerous functions within the regulator circuit, in particular monitoring and safety functions. It is however also possible for the microprocessor to be adapted to control the power fed to the electric motor subject to the operating signal.

Abstract: The invention relates to a switch for electrical hand tools, comprising: a housing, switch means incorporated in the housing, at least one wire opening arranged in the housing for throughfeed of a connecting wire, at least one contact incorporated in the housing for making galvanic contact between a connecting wire placed through the opening and the switch means, and at least one sealing element fitting into the at least one wire opening, manufactured from a flexible material and provided with a throughfeed opening, wherein the sealing element has a first part in which a throughfeed opening has a diameter decreasing in the direction toward the interior of the housing. Due to this measure a very effective seal is obtained since the opening with decreasing diameter is widened slightly when the wire is inserted, whereby the seal is forced closely against the wire.

Abstract: The invention relates to a control circuit for controlling a DC voltage power supply, whereby the control circuit comprises a switching element connected in series to the motor and a bypass switch connected in parallel to the electromotor for braking the electromotor by means of bypassing, with the bypass switch being formed by a semiconductor and the control circuit comprising a control circuit for controlling the bypass switch and a detector connected to the control circuit for detecting the status of the switching element. Semiconductors are less sensitive to vibrations and dirt. They are furthermore so small that they can easily be mounted on the same carrier as the other components of the control circuit. The control circuit is preferably arranged for gradually increasing the conductivity of the bypass switch once the switching element is open. Mechanical shocks when the tool is switched off are prevented by means of the partial conductivity of the semiconductor switch.

Abstract: The invention relates to an assembly of a carrier for electrical components that are arranged for producing more heat than can be dissipated via natural cooling at least under certain operating conditions and a cooling body mechanically and thermally connected thereto, whereby the carrier is provided with a metal part that is connected to the cooling body by means of a metallic connection. Mounting a metal part on the carrier makes it possible to form a metallic connection between the metal part and the metal cooling body. The invention also relates to a method for assembling an assembly of a carrier for heat-producing electrical components and a cooling body mechanically and thermally connected thereto, whereby the components are initially mounted on the carrier and a metal part of the carrier is then connected to the cooling body by means of a metallic connection.

Abstract: The invention relates to a control circuit for controlling the power supplied from a power source to an electromotor, whereby the control circuit comprises a semiconductor switching element connected in series to the electromotor and the power source for controlling the power supplied to the electromotor and operating means connected to the semiconductor switching element for controlling the semiconductor switching element, whereby the operating means are arranged for controlling the semiconductor switching element when the control range of the semiconductor switching element is exceeded for at least a moment in a fully conducting state. Because the current reaches this value for at least a moment, the switch no longer has to interrupt a relatively large current.

Abstract: The invention relates to a switch for controlling the power to be fed to an electric motor of an electrical hand tool, which comprises a power supply connection, a motor connection, a controllable semiconductor connected between the motor connection and the power supply connection, a control circuit for controlling the semiconductor, and a safety circuit, wherein the switch comprises a cumulation circuit which is adapted to repeatedly measure a quantity prevailing in the switch or in its vicinity, assign a count value to the measured value of the quantity, cumulate the count values and generate a signal when the cumulated count value reaches a predetermined value. As a result of these measures the prior history of a component is included in the assessment of whether a situation is occurring which threatens the quality of this component.

Abstract: The invention relates to a switch unit for an electric tool, wherein the switch unit comprises heat-dissipating components, wherein the switch unit comprises a fan, which is adapted to cool the heat-dissipating components. The fan will herein generate an airflow which is guided via the relevant components. The heat developed in these components can be discharged so that the relevant components, even in the case of high power, can be given small dimensions. According to a particular preferred embodiment, the heat-dissipating components are thermally coupled to a cooling body, and the fan is adapted to cool the cooling body.

Abstract: A hybrid printed circuit carrier including a ceramic carrier, traces applied on the carrier, circuit components located on said carrier and a plurality of switch contacts. The switch contacts form a portion of a movable switch and are fixedly applied on the same surface of the carrier as the traces and the circuit components. The application of at least a portion of the fixed contacts of the moving switch allows these contacts to be located on the carrier in the same process step as the location of the other components to be located on the carrier. This application can be executed easily using a pick-and-place apparatus, thereby avoiding labor-intensive manual processing. Also, contact elements for a plug connection with wires can be applied on the carrier. The location of the contact elements onto said carriers obviates the need for screw connections, etcetera for making electrical connections with the switch unit, which are classically formed by wires.

Abstract: A switch for electric hand-tools includes: a switch housing with a switching device arranged therein; and a carriage arranged movably in the housing and which is drivable by a trigger connected thereto. The carriage is provided with at least one slider for sliding over a potentiometer track and with at least one movable contact of a mechanical switch. The switch housing is provided with an electrical connecting system which, when a module is arranged on the switch housing, is adapted to form an electrical connection between the switch housing and the module. The switch housing with the switching device arranged therein can be adapted, by connecting a module thereto, to provide an additional switch function and to adapt to a specific method of connection of the wires to be connected to the switch.

Abstract: The invention relates to an adjustable resistor comprising a strip of resistance material arranged on an insulating carrier and a slider made of conductive material guidable along the strip and contacting the strip, wherein the slider is manufactured from elastomeric material. A slider manufactured from an elastomeric material will, as a result of its flexibility, make contact with the resistance strip over a relatively large part of the width of the resistance strip so flat the problems of an uneven current distribution associated with one-point contact are avoided. The use of an elastomeric material further provides the option of dimensioning and shaping the slider such that it can be handled easily by means of a positioning machine, and the problems of the usually elongate rigid sliders on the production line are avoided. The slider is preferably manufactured from conductive rubber or a conductive plastic.

Abstract: The invention relates to a switch comprising a carrier which is manufactured substantially from plastic and in which fixed contacts are arranged, and a part which is movable relative to the carrier and in which movable contacts are arranged, wherein the fixed contacts are enclosed by plastic on at least a part of all their sides, so that the fixed contacts are fixed in plastic. According to a first preferred embodiment at least one plastic element extends at least on a first side of the fixed contacts, which plastic element leaves clear a part of the surface on the first side of the fixed contacts. Sufficient fixation is herein obtained by the plastic element, while it will be apparent that a contact face of the contacts must remain free in order to be able to function as a contact.