DD160250A3 - ARRANGEMENT FOR PHASE INTERFACE CONTROL USING THE HALLE EFFECT SENSOR - Google Patents

Abstract

The invention includes a phase control, which is based on the superposition of two magnetic fields, one of which is changed network synchronously, while the second is also changed by an operating member. The field strength is evaluated by a Hall effect sensor, which activates the circuit breaker. The arrangement allows a great deal of freedom in the design of the controls and allows the supply of Hilfsgroessen (extension to the controller) and a remote control. Compared to conventional solutions, a much better functional reliability is available under unfavorable environmental conditions. Application examples include impact drills, hand mixers, vacuum cleaners and other devices.

Description

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Title de? invention

Arrangement for phase-cutting control by means of Hall effect sensor

Field of application of the invention

The invention relates to a phase sense control, which can also be extended to a control when needed, preferably for small electrical appliances, in soft high requirements with regard to contamination and vibration and wear-free adjustability exist · This concerns z. Electric drills, ordinary home improvement machines, hand mixers, food processors and vacuum cleaners ·

Characteristic of the known technical solutions

Known devices have invariably variable resistors for setpoint input, followed by a corresponding circuit for changing the ignition angle. The tolerances are usually compensated by setting resistances. These components are sensitive to increased dirt and high mechanical load device ·

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Arrangements with Hall sensors are known in which the sensitivity range of the sensor is changed by means of externally mounted magnetic auxiliaries or a correction of errors (temperature variation) takes place (US Pat. No. 3,974,425) (BRD AS 23 37 691) Permanent magnet is generated by a rotating flywheel alternating field in a pulsating DC magnetic field (BRD OS 25 39 548) V

It is furthermore state of the art that, in the case of phase-angle controllers, a sawtooth voltage is compared with a variable direct voltage in order to derive therefrom a change in the ignition angle.

Object of the invention

The aim of the invention is a simple reliable solution that replaces the previously used adjustment resistor while allowing a low circuit complexity

 In addition, the designer should be given greater freedom for the structural design of the control »

Explanation of the essence of the invention

The object of the invention is to find an arrangement with which a direct implementation of a desired magnetic variable in a corresponding variable ignition angle can be done ¹ ;

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By an electronic circuit a saw tooth-like magnetic field is generated in a magnetic coil, which runs synchronously with the mains frequency.

This magnetic field is superimposed on another variable field.

If one assigns a Hall sensor with threshold value switch in the area of influence of both fields, the ignition angle can be adjusted by changing a magnetic field via the switching threshold of the Hall sensor.

Depending on the data and accuracy of the Hall sensor, the response or shutdown threshold can be used. Furthermore, an arrangement of the magnetic fields additively or subtractively possible, so that there are four variants. In order to bring the Hall sensor at every NuIldurchgang the AC voltage with certainty in the starting position, the superposition of the sawtooth-like magnetic field with a needle pulse before the end of each half wave is appropriate.

embodiment

The function will be explained in more detail with reference to a practical example according to FIG. 1.

By the control electronics 1, a magnetic field according to curve a is generated in the winding 2. This second magnetic field is added by the permanent magnet 3 located on the axis of the operating element. Assume the case that both fields are opposite and the Hall sensor 6 indicates the extinction of the fields. The function is now

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as a. Magnetic comparator to understand, the switching operation at the output of the Hall sensor is always at equality of both fields, By changing the permanent magnet 3 shifts the intersection of the fields and thus the switching operation in the phase angle ·

The output of the Hall sensor triggers the ignition of the triac or thyristor in a known manner from «The adjustment of the arrangement is purely magnetic by adjusting the permanent magnet 3 on the axis and a variable magnetic shunt. 4

In an additionally arranged winding 5, an auxiliary variable can be entered so that a control loop is created «

In Fig. 1, diagram a, the magnetic field strength in relation to the mains AC voltage is entered; mo is the magnetic zero position. On the line A ^ (high output), the ignition pulse is triggered, by varying this threshold, the phase shift of the output signal (ignition pulse) occurs · On the line A- ^ (output low), the arrangement is reset by the needle pulse.

Claims (1)

-S 227 Invention claim: Arrangement for phase-angle control by means of Hall effect sensor, which is arranged in the air gap of a magnetic circuit and which is influenced by a DC magnetic field, with a coil which generates a phase-synchronous magnetic field, characterized in that the coil (2) is connected to an electronic control unit (1), such that the phase-synchronous magnetic field having a sawtooth waveform superimposed on a needle pulse at the end of each half-period is generated in the coil, that an auxiliary winding and a rotatable permanent magnet are arranged in series in the magnetic circuit, with which the direct magnetic field -r can be changed '·