JPH0460522B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is used, for example, in an angle detector used to detect the accelerator opening and vehicle height of automobiles.

(Prior art) A device that detects two positions, an upper command area and a lower command area, by arranging two magnetoelectric transducers was developed in 1983-
Although disclosed in Japanese Patent No. 104710, this conventional device only detects two positions and cannot detect changes in the rotation angle of a lever or the like.

On the other hand, as shown in FIG.
The strip plates 2 made of a magnetic material in the shape of a letter are combined, and the strip plates 2
After forming a magnetic path for the main magnetic flux and positioning the magnetically sensitive element 4 disposed on the rod 3 between the opposing walls of the strip plate 2, the rod 3 is moved and the magnetically sensitive element 4 is placed between the magnet 1 and the magnetically sensitive element 4. When the leakage magnetic flux is measured by the magnetic sensing element 4 while changing the dimension X between the two, a relationship as shown in FIG. 5 is obtained. That is, as the dimension X between the magnet 1 and the magnetic sensing element 4 increases, the density of the detected leakage magnetic flux decreases, and the relationship shown by the solid line is obtained. This solid line is relatively gentle and substantially straight.

(Problems to be Solved by the Present Invention) The present invention utilizes the relationships shown in FIG.
That is, the problem to be solved is to confirm the position of the magnetically sensitive element with respect to the magnet by detecting leakage magnetic flux, and to make it possible to detect angular changes, which was previously impossible.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention arranges a magnetically sensitive element at the tip of a lever that is rotatable with respect to the case, and between the opposing walls of the arc-shaped strip plate. A technical means is used to measure the change in the relative rotation angle of the lever and the case by positioning a magnetically sensitive element and detecting the leakage magnetic flux from the strip.

(Operation) When the lever rotates and the magnetically sensitive element moves from one position to another, the amount of leakage magnetic flux measured also changes according to the relationship shown in FIG. Since this change represents a certain circular arc (because the magnetic sensing element moves in a circle), it can necessarily be converted into a change in the angle of the lever. In this way, the relative rotation angle between the lever and the case can be detected.

(Example) Refer to Figures 1-3. A lever 6 made of a non-magnetic material is rotatably supported at a proper position of a case 5 made of a non-magnetic material. The shaft portion of the lever 6 is extended to the outside of the case 5, and the link 7 is fixed to the shaft portion with a bolt 8. The link 7 is connected to an accelerator opening and vehicle height detection mechanism. A magnetic sensing element 4 for detecting leakage magnetic flux is fixed to the tip of the lever 6, and a lead wire 9 for the element is extended to the outside.

A magnet 1 and an arc-shaped strip plate 10 are fixed inside the case 5. The strip plate 10 has a substantially horizontal U-shape and is made of a magnetic material, and its end portion is coupled to the magnet 1. The strip 10 thus forms a magnetic path for the main magnetic flux. The magnetic sensing element 4 fixed to the lever 6 is attached to the strip plate 10.
between the opposite walls. Since the arc of the strip 10 coincides with the movement of the magnetically sensitive element 4 about the shaft of the lever 6, the magnetically sensitive element 4 is always placed between the opposing walls of the strip 10 while the lever 6 is rotating. This means that 11 is a cover made of non-magnetic material. Note that the lead wire 9 is connected to a magnetic flux measuring device (not shown).

In the state shown in FIG. 3, first, the leakage magnetic flux from the strip plate 10 is detected by the magnetic sensing element 4, and this detected amount is supplied to the measuring instrument via the lead wire 9 and stored. Next, link 7 moves and lever 6
When the magnetic sensing element 4 rotates about its shaft, the position of the magnetic sensing element 4 also changes, and the amount of leakage magnetic flux detected also changes. Therefore, the amount of leakage magnetic flux detected at the new position of the magnetically sensitive element 4 is compared with the stored magnetic flux amount at the previous position to determine the amount of movement of the magnetically sensitive element 4. In fact, since the magnetically sensitive element 4 moves on an arc whose radius is the length of the lever 6, the measurement of the amount of movement is immediately converted into an angle by a measuring device.
In this way, the relative rotation angle between the link 7 and the lever 6 can be known.

(Effects) The angle detector according to the present invention has a simple structure because the arc drawn by the magnetically sensitive element during movement is simply made to substantially coincide with the arc of the strip.

[Brief explanation of drawings]

FIG. 1 is a plan view of an angle detector as an example of the present invention;
2 is a sectional view taken from the direction of the arrow in FIG. 1, FIG. 3 is a perspective view showing a strip plate and a lever, FIG. 4 is a perspective view showing an example of a device for measuring leakage magnetic flux, and FIG.
The figure is a graph diagram showing the relationship between the distance X from the magnet and the leakage magnetic flux density. In the figure: 1... Magnet, 4... Magnetic sensing element, 6...
...Lever, 10...Strip plate.

Claims (1)

[Claims] 1. A magnet, an arc-shaped strip made of a magnetic material connected to the magnet and forming a magnetic path for the main magnetic flux, and a magnetically sensitive element at the tip of the arc-shaped strip that is rotatably directed to a case that holds the strip. and a lever made of a non-magnetic material, wherein the magnetic sensing element is located on the opposing wall surface of the strip plate, detects leakage magnetic flux from between the opposing walls, and detects the relative rotation angle between the case and the lever. An angle detector characterized by detecting.