DE102005060906A1 - Speed and position detection device - Google Patents

Abstract

The invention is based on a speed and position detection device for detecting speeds and / or positions of a rotatable body (22), with at least two sensor elements (12, 16) which, with their active surfaces (14, 18), are in a sensing area (24) of the body (22) are arranged. DOLLAR A It is proposed that the sensor elements (12, 16) be aligned with their active surfaces (14, 18) at least almost parallel, the active surfaces (14, 18) having an angle (alpha) between 0 ° and 10 ° to one another.

Description

State of technology

The The invention is based on a speed and position detection device according to the preamble of claim 1.

to Detecting speed or position / position detection will be today Application-specific sensors for a wide variety of applications, so-called ASICS, which i.a. Sinusoidal signals as output signal output.

Become high requirements regarding accuracy, such as aggregates in power splitters Hybrid drives, the resolver principle is used. This kind The position and speed sensing is costly.

From the EP 740776 B1 a device for angle measurement in a rotatable body is known, in which two Hall sensor elements are used, which are arranged offset by 90 ° to each other on a shaft to be sensed.

From the EP 0877916 B1 is a device with absolute sensors known, with which rotation angle of more than 360 ° can be detected.

From the EP 1 460 764 A1 is a resolver known that can be used at high rotational speeds.

epiphany the invention

It becomes a speed and position detection device for detection of rotational speeds and / or position of a rotatable body, with proposed at least two sensor elements whose active surfaces in a sensing area of the body are arranged, wherein the sensor elements with their active surfaces almost are aligned parallel and the active surfaces with an angular offset an angle between 0 ° and 10 ° to each other exhibit. Unlike conventional Systems where sensor active surfaces around 90 ° or 45 ° tilted against each other could be, is only a small or vanishing angular misalignment of active surfaces provided, preferably, the angular offset is less than 10 °. Through this simple and inexpensive arrangement Nevertheless, a high measurement accuracy can be achieved. The usual sinusoidal and cosinusoidal Output signals via Be a predetermined mechanical or electrical rotation range. It can commercial ASIC modules (Application-Specific Integrated Circuit) in combination be arranged so that two electrically phase-shifted output signals the absolute value of the position of a sen sorelements output and also the errors of both sensor elements are averaged.

In a cheap one Embodiment are the sensor elements as integrated semiconductor devices formed, preferably as a commercial application-specific Sensors designed to detect absolute angles. This poses a very inexpensive training.

In a cheap one Design, the sensor elements are similar.

In In an alternative embodiment, the sensor elements are different designed so that the one sensor element n vibrations as an output signal Spends while the other sensor element outputs more or less than n vibrations, when the body turns by a certain angle. Preferably, the differ emitted as output signal oscillations of the sensor elements about a vibration. In the type of vernier principle can with this embodiment more than one revolution of the body in Absolute values are sensed.

Basically be provided that the sensor elements rotate with the body and a magnetic signal from a fixed magnetic device detect.

drawings

Further Embodiments, Aspects and advantages of the invention are also independent of their summary in claims, without restriction to the general public, illustrated below by means of drawings embodiments the invention.

in the Show:

1 a representation of typical output signals of a conventional absolute encoder system;

2 a representation of typical output signals of a preferred speed and position detection device;

3 a preferred embodiment of a speed and position detection device according to the invention; and

4 Output signals of a preferred speed and position detection device with different sensor elements.

1 shows a representation of typical output signals of a conventional absolute encoder system for a speed and position detection Recognizable are the usual sinusoidal and cosinusoidal output signals S as a function of an electrical rotation angle φ1 and a mechanical rotation angle φ2 corresponding thereto.

2 shows a representation of typical output signals S of a preferred speed and position detection device 10 as they are in 3 is shown. Two sensor elements 12 . 16 a rotatable body 22 are with their active areas 14 . 18 in a sensing area 24 of the body 22 arranged and detect, for example, a temporally periodically variable magnetic field of a magnet 20 ,

The sensor elements 12 . 16 are with their active areas 14 . 18 aligned almost parallel, with the active surfaces 14 . 18 have a small angular offset with an angle α to each other, which is preferably less than 10 °. The angle α can also be 0 °, so that the active surfaces 14 . 18 are parallel.

The sensor elements 12 . 16 are integrated as semiconductor devices, in particular as a commercial application-specific sensors (ASICs) for detecting absolute angles.

The output signals S of 2 show in comparison with those of 1 over the same angular range of electrical and mechanical angles of rotation φ1, φ2 of the body 22 the double number of signals in regular phase relationship, corresponding to the fact that the sensor elements 12 . 16 are formed similar and in particular have the same principle of action, for example after the Hall effect or the magnetorestrictive effect and the like. More.

In 4 are output signals of a preferred speed and position detection device 10 with different Sensorele elements 12 . 16 shown. The arrangement of the components corresponds to that in 3 , whose description is referenced.

By means of the vernier principle here is the one sensor element 12 or 16 n oscillations as output signal S out, while the other sensor element 16 or 12 more or less than n outputs vibrations. In the 4 are the sensor elements 12 . 16 chosen so that the one n oscillations per mechanical revolution of the body 22 outputs and the other n + 1 vibrations. This allows revolutions of more than 360 ° to be detected.

Claims (7)

Speed and position detecting device for detecting rotational speeds and / or positions of a rotatable body ( 22 ), with at least two sensor elements ( 12 . 16 ), with their active surfaces ( 14 . 18 ) in a sensing region ( 24 ) of the body ( 22 ) are arranged, characterized in that the sensor elements ( 12 . 16 ) with their active surfaces ( 14 . 18 ) are aligned at least nearly parallel, wherein the active surfaces ( 14 . 18 ) have an angle (α) between 0 ° and 10 ° to each other. Device according to claim 1, characterized in that the sensor elements ( 12 . 16 integrated) are designed as semiconductor components. Device according to claim 1 or 2, characterized in that the sensor elements ( 12 . 16 ) are designed as commercially available application-specific sensors for detecting absolute angles. Device according to one of the preceding claims, characterized in that the sensor elements ( 12 . 16 ) are formed identically. Device according to one of claims 1 to 3, characterized in that the sensor elements ( 12 . 16 ) are formed differently such that the one sensor element ( 12 or 16 ) outputs vibrations as an output signal while the other sensor element ( 16 or 12 ) outputs more or less than n vibrations. Device according to Claim 5, characterized in that the oscillations of the sensor elements output as output signals ( 12 . 16 ) to distinguish one vibration. Device according to one of the preceding claims, characterized characterized in that the angular offset (α) is less than 10 °.