DE2753738A1 - Angular speed measurement device - has circular magnet array on rotating body and has induction coil pick=up sensors - Google Patents

Abstract

An angular speed measurement device has a number of signal generator devices arranged in a circle on a rotating part (6) and working in conjunction with two sensors placed apart. It achieves higher accuracy than usual using simple techniques and exactly determines angular speed variations. The speed is derived from the duration of a pulse whose beginning and end are defined by the same signal generator as it passes the first and second sensor. The tipole magnets (1, 2) are induction coils and the generator multipole magnets consisting of smooth locally magnetised discs (4).

Description

Winkelgeschwindigkeltsinesser

The invention relates to an angular speedometer in which a number of encoder elements arranged on a circle on a rotating part that work together with two spaced apart sensors.

Such a Winliel speedometer is belvannt tDE-oS 24 46 132). The encoder elements are teeth that are on the circumference of a non-magnetized Wheel made of ferromagnetic material are arranged. The sensors are from two formed in the vicinity of the circumference of the wheel arranged magnetic cores on which a winding is provided in each case, and a first alternating current excitation generator, which is connected to send a first phase carrier signal to one of the Windings conducts, a second alternator, which is so connected, that it feeds a second carrier signal to a second phase of the other winding, wherein the second phase is 180 ° with respect to the first phase, and one balanced output circuit with an output terminal to which a composite Signal is present, which results from the carrier signals and dwr Rotatio- of the wheel. By arranging two sensors in the manner described, it is possible to evaluate the zero crossing as a defined position of each tooth. This will Although the impulse of each tooth is always measured in the same position to the sensor, however, the inaccuracies caused by an incorrect division persist of the gear. These division errors falsify the measurement result.

The invention is based on the object, with simple means, a Angle speedometer to provide great accuracy at. the changes the angular velocity can be determined exactly.

This object is achieved in that as a measure for the angular velocity is the duration of a pulse, its beginning or end from one and the same encoder while passing the first or second sensor is determined.

Since in the arrangement according to the invention, the measuring path through the distance of the sensors is given and always remains constant, division errors go with the Encoder arrangement is not included in the measurement result.

Appropriate sensors and transmitters are proposed in claims 2 to 4. The embodiment according to claim 2 is suitable due to the low air friction losses for systems with low power. The sensors according to claim 3 can easily parts available on the market. Finally, the sensors can according to claim 4 also work with non-magnetizable encoders. Otherwise are still numerous other sensors and transmitters are conceivable that are used in the angular velocity meter according to the invention can be applied.

With known electronic aids, it is possible to achieve precise Detection of the signal interval from the signal of the first sensor the leading edge and from the signal of the second sensor to the backward edge of a pulse form, the duration of which is a measure of the angular velocity. The distance of the two sensors is expediently chosen to be somewhat smaller than the distance the teeth. However, special processing electronics also leave a larger one Sensor distance to.

The change in the pulse duration is a measure of the change in angular velocity and this in turn provides information about the presence and in certain cases Extent of pressure vibrations.

An exemplary embodiment of the invention is shown in the drawing.

Fig. 1 shows the schematic structure of an angular velocity meter according to the invention, Fig. 2 shows the processing of the signals in a diagram.

In a carrier 3, sensors 1 and 2 are at a fixed distance a arranged from each other. Encoder elements 4, which rotate on a rotating in the direction of rotation 6 Disc 5 are arranged, move at a small distance from the sensors 1 and 2 over. The distance between the sensors 4 can be chosen arbitrarily, as one Measured value is only assigned to one encoder element. But should rapid changes in angular velocity determined is a narrow one for adequate resolution, but not equal encoder distribution necessarily required.

In Figure 2 are the signal sequences of the first and second sensor 1, 2 applied one on top of the other. In the lower part of the diagram is the processed Output signal shown over time, its leading edge 7 from a signal 8 of the sensor 1 and its rear edge 9 from a signal 10 of the sensor 2 is formed. Both signals are generated by the same encoder.

L e r s e i t e

Claims (4)

Claims angular speed meter, in which a number of boar learners are arranged on a circle on a rotating part, the cooperate with two spaced apart sensors, thereby characterized in that the duration of a pulse as a measure of the angular velocity serves, the beginning or end of which by one and the same encoder (4) while passing of the first or second sensor (1, 2) is determined. 2. Angular velocity meter according to claim 1, characterized in that that the sensors (1, 2) consist of induction coils and the transmitter (4) of one rotating multipolar magnet formed from a smooth, locally magnetized disc. 3. Angular speed meter according to claim 1, characterized in that that the sensors (1, 2) consist of magnetically controllable semiconductors and the Encoder (4) are formed by a rotating, multi-pole magnet. 4. Angular speed meter according to claim 1, characterized by Sensors (1, 2), which consist of two coils excited by a high frequency voltage.