JP2001099687A - Self-holding position sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a self-holding position sensor with the use of an inversion chip inverting by a magnetic force. SOLUTION: As shown in (a), inversion chips 1 are arranged in one- dimensional direction so that an attraction force acts between different poles, and a rotary shaft 2 is supported by frames of both sides not shown. The inversion chip 1 is made rotatable the around the rotary shaft 2 as shown in (b)-(d). The inversion chip 1 stably self holds its attitude by an attraction force acting between the inversion chips 1 so long as no effect of the other magnetic force is strongly applied to the chip. When a magnet 3 moves in one direction in the vicinity of a rear face of the inversion chip 1 with one magnetic pole being directed to the inversion chip 1, the inversion chip 1 is inverted. As is clear from (b)-(d), when the magnet 3 moves up in accordance with a movement of a detect direction with an N pole approached to the inversion chip 1, an S pole of the inversion chip 1 to which the magnet 3 approaches is attracted to the N pole of the magnet 3 against the attraction force between the inversion chips 1, and is rotated as shown in (b)-(d). After the magnet 3 passes, the inversion chip 1 is inverted to have the rear face 1b turned front as shown in (e).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-holding type position sensor which can be used for detecting, for example, an alarm position of a float of an area flow meter.

[0002]

2. Description of the Related Art For example, there is known a conventional area-type flowmeter for detecting and displaying an upper / lower limit alarm position by combining a reed switch with a bias magnet.

[0003]

However, in general, reed switches are very delicate and require careful attention when handling them. Sensitivity may change.

A self-holding sensor manufactured in combination with a reed switch and a bias magnet is affected by terrestrial magnetism or has a long term because the bias magnet having a very small magnetic force holds the contact of the reed switch. When used over a range, the bias magnet may be degraded, making it difficult to maintain its original performance.

Furthermore, in the case of the optical type, the self-holding type reed switch is structurally self-holding, but relies on an electric circuit, and requires a backup power supply, an arithmetic circuit, an optical element, etc., and is inexpensive. It is difficult to make.

It is an object of the present invention to provide a self-holding position sensor which has the self-holding function, has a simple structure, and does not require a lead wire or the like, which solves the above-mentioned problems.

[0007]

A self-holding type position sensor according to the present invention for achieving the above object has magnets having opposite poles at both ends, different display surfaces on the front and back surfaces, and is parallel to the surface direction. And at least two reversing chips having a rotation axis in a direction orthogonal to the magnetic pole direction, facing the different poles so that a suction force acts between different poles between the different reversing tips, in a one-dimensional direction. By arranging one of the magnet poles attached to the detected end and having a stronger attraction force than the inversion chips between the inversion chips in the one-dimensional direction while approaching the inversion chip, The position of the detected end is detected by reversing the reversing tip around the rotation axis by a magnetic flux.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiment. FIG. 1 shows a principle diagram of a self-holding type position sensor according to the present invention. For example, three reversing tips 1 mainly composed of, for example, bar magnets having different magnetic poles at both ends are arranged in a one-dimensional direction so that an attractive force acts between different poles between different reversing tips 1. . Each reversing chip 1 is provided with a rotation axis 2 in a direction orthogonal to the direction between the magnetic poles, and the reversing chip 1 rotates around the rotation axis 2 so that the front surface 1 a or the back surface 1 a
b is displayed. And the inverted tip 1
The front surface 1a and the back surface 1b are provided with different colors, shades, marks, and the like so as to be visually or optically distinguishable. Then, a magnet 3 having an attraction force stronger than the attraction force acting between the reversing chips 1 is attached to a detected end (not shown), and is arranged movably along the one-dimensional direction in which the reversing chips 1 are arranged. I have.

For example, as shown in FIG. 1A, the reversing tips 1 are arranged in a one-dimensional direction so that a suction force acts between different poles, and the rotating shafts 2 are respectively supported by frames on both sides (not shown). The inverted tip 1 is shown in FIG.
It is rotatable as shown in (b) to (d).

As long as the reversing tip 1 is not strongly affected by other magnetic forces, its posture is stably held by the attraction force acting between the reversing tips 1. However, when the magnet 3 moves in a certain direction near the back side of the inverted tip 1 with one magnetic pole of the magnet 3 facing the inverted tip 1, the inverted tip 1 is inverted. For example, as shown in FIGS. 1B to 1D, when the N pole of the magnet 3 rises with the movement in the detected direction on the back side of the reversing chip 1, the reversing chip 1 in which the magnet 3 approaches is reversed. The S-pole is attracted to the N-pole of the magnet 3 against the attraction of the chips 1 and rotates as shown in FIGS. 1 (b) to (d) and FIGS. 2 (b) to (d),
After passing through the magnet 3, as shown in FIG. 1 (e) and FIG. 2 (e), the reversing chip 1 is turned over so that the back surface 1b can be seen.

In this state, the inverted tip 1
The two are self-held by the suction force between different poles, and the posture is stabilized. Here, when the magnet 3 descends, it returns to the state of FIG. 1A through the states of FIGS. 1D, 1C, and 1B, and self-holds the posture as it is.

FIG. 3 is a perspective view showing an example in which the present invention is applied to an area type flowmeter. The taper tube 11 through which a fluid to be measured passes is made of a non-magnetic material such as brass or glass. A float 12 which is a detection end is provided inside the fluid so as to float in the fluid and move up and down. A magnet 13 is attached to the float 12, and at the center of the outer surface of the tapered tube 11, for example, three reversing chips 1 are arranged in a vertically reversible manner.

In this case, since the float 11 is easily rotated about its central axis in the tapered tube 11, the magnet 3 as described in FIG. It is hard to let. Therefore, as shown in the enlarged perspective view of FIG. 4, two permanent magnets are directly connected to each other in the up-down direction. Thereby, the magnetic flux passing from the magnet 13 to the N pole can be largely bypassed, and an attractive force can be applied to the S pole of the reversing tip 1.

When the flow rate changes and the float 12 moves up and down, the front and back surfaces of the reversing chip 1 corresponding to the position of the float 12 are reversed according to the principle described with reference to FIG. Can be visually determined. For example, if the flow rate increases and the float 1
If 2 is higher than the position of the inverted tip 1,
The inverted chip 1 is supported in a state where the back surface 1b is displayed, and when the flow rate decreases and the float 12 is lowered, the inverted chip 1 indicates the front surface 1a.

This is because the float 12 moving up and down cannot be visually recognized from the outside, especially when the flow rate changes in the taper tube 11 made of metal. Can be visually recognized through the reversing chip 1.

Further, in the flow gauge, the sensors using the reversing tip can be arranged vertically and used as an upper limit alarm and a lower limit alarm. Further, the detection of the front and back of the display surface of the reversing chip can be performed photoelectrically by a photoelectric sensor.

In the above description, the inverted chips 1 are arranged vertically, but they can also be arranged horizontally or diagonally. Further, the magnet attached to the detected end may be an electromagnet instead of a permanent magnet.

[0018]

As described above, the self-holding type position sensor according to the present invention is attached to the detected end in the one-dimensional direction where the reversing chips are arranged, and has a magnet having a higher attraction force than the attraction force between the reversing chips. Is moved, the inverted chip is inverted to become an inverted display surface, and the position of the detected end can be detected by visually or photoelectrically determining the front and back surfaces of the inverted chip.

[Brief description of the drawings]

FIG. 1 is a principle diagram.

FIG. 2 is a front view of a reversing chip.

FIG. 3 is a perspective view when used in an area flow meter.

FIG. 4 is an enlarged perspective view of a magnet.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 inverted tip 1a front surface 1b back surface 2 rotating shaft 3, 13 magnet 11 taper tube 12 float

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F030 CA01 CE15 CF11 2F077 JJ23

Claims (2)

[Claims] 1. At least two inverting chips having magnets of opposite poles at both ends and different display surfaces on the front and back surfaces and having a rotation axis in a direction parallel to the surface direction and orthogonal to the magnetic pole direction are provided. A magnet having a stronger attraction force than the attraction force of the inverted chips attached to the detected end, with the different electrodes facing each other and arranged in a one-dimensional direction so that the attraction force acts between the different electrodes between the inverted chips. By moving any of the magnetic poles in the one-dimensional direction while approaching the reversing tip, the reversing tip is reversed around the rotation axis by the magnetic flux of the magnet, and the position of the detected end is changed. A self-holding position sensor characterized by detecting. 2. The self-holding type position sensor according to claim 1, wherein the position of the detected end is detected by photoelectrically detecting a display surface of the inverted chip.