CN111486929A

CN111486929A - Three-wire linear liquid level sensor based on magnetic resistance non-contact

Info

Publication number: CN111486929A
Application number: CN202010377439.1A
Authority: CN
Inventors: 方锡邦; 吕小雪; 鲁海林
Original assignee: Hefei Bangli Electronic Co ltd
Current assignee: Hefei Bangli Electronic Co ltd
Priority date: 2020-05-07
Filing date: 2020-05-07
Publication date: 2020-08-04
Anticipated expiration: 2040-05-07
Also published as: CN111486929B

Abstract

The invention discloses a magnetic resistance non-contact based three-wire linear liquid level sensor which comprises a signal wire harness and an information pipe, wherein a floater is arranged on the information pipe, a magnet is fixed in the floater, a circuit board is arranged in the information pipe, and a three-wire circuit is printed on the circuit board. The invention has the advantages that based on the magneto-resistance effect, when the floater is positioned at different positions, the magneto-resistance elements at corresponding positions are triggered to be conducted, so that the position of the floater is detected, and a resistance signal is output; the circuit board is sealed in the pipeline and isolated from the fuel oil, and has strong corrosion resistance, safety and reliability.

Description

Three-wire linear liquid level sensor based on magnetic resistance non-contact

Technical Field

The invention relates to the technical field of liquid level sensors, in particular to a linear liquid level sensor with three wires based on magnetic resistance non-contact.

Background

The sensor for measuring the oil level of the oil tank in the existing vehicle is mainly a dry reed type oil level sensor and outputs resistance signals. The resistance signal is converted into a current or voltage signal through an external conversion circuit. The reed switch is easy to damage in the assembling and welding process due to the glass packaging structure, so that the reliability and the accuracy of the reed switch are influenced. The reed switch is a mechanical structure, and the service life and the vibration resistance of the reed switch are inferior to those of a semiconductor electronic device.

Disclosure of Invention

The invention aims to provide a three-wire linear liquid level sensor based on magnetic resistance non-contact, which solves the problems of poor reliability and accuracy and short service life of the traditional liquid level sensor.

The invention realizes the purpose through the following technical scheme:

a three-wire system linear liquid level sensor based on magnetic resistance non-contact comprises a signal wire harness and an information pipe, wherein a floater is arranged on the information pipe, a magnet is fixed in the floater, a circuit board is arranged in the information pipe, a three-wire system circuit is printed on the circuit board and consists of a signal output end, a grounding end, a power end, a resistor string and a magnetic resistance chip sequence, the end of the resistor string is connected with the signal output end, the signal pin of each magnetic resistance element in the magnetic resistance chip sequence is correspondingly connected with the resistor in the resistor string one by one, the power pin of each magnetic resistance element is connected with the power end, and the grounding pin of each magnetic resistance element is connected with the grounding end;

and the signal output end, the grounding end and the power supply end are all connected with a signal wire harness.

The liquid level sensor is further improved in that the liquid level sensor further comprises a top seat used for fixing the information pipe, an oil suction pipe and an oil return pipe which are used for supplying oil to a vehicle engine are mounted on the top seat, and the oil suction pipe, the oil return pipe and the information pipe are arranged side by side.

The further improvement is that the top seat is also provided with a heating pipe, the heating pipe is connected with circulating cooling liquid of a vehicle engine, and the heating pipe surrounds the lower half parts of the oil suction pipe and the oil return pipe.

The liquid level sensor is further improved in that the liquid level sensor further comprises a buffer tray, and the buffer tray is used for fixing the bottoms of the oil suction pipe, the oil return pipe and the heating pipe.

The invention has the beneficial effects that: based on the magneto-resistance effect, when the floater is positioned at different positions, the magneto-resistance elements at corresponding positions are triggered to be conducted, so that the position of the floater is detected, a resistance signal is output, the circuit board directly outputs the resistance signal by using a three-wire system resistance output mode, the signal at a using end is not required to be changed, and only a power supply signal is required to be provided; the circuit board is sealed in the pipeline and isolated from the fuel oil, and has strong corrosion resistance, safety and reliability.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a circuit configuration diagram of a three-wire circuit;

in the figure: 1. a signal harness; 2. information management; 3. a float; 4. a top seat; 5. an oil suction pipe; 6. an oil return pipe; 7. heating a tube; 8. a buffer tray.

Detailed Description

The present application will now be described in further detail with reference to the drawings, it should be noted that the following detailed description is given for illustrative purposes only and is not to be construed as limiting the scope of the present application, as those skilled in the art will be able to make numerous insubstantial modifications and adaptations to the present application based on the above disclosure.

Referring to fig. 1 and 2, a linear liquid level sensor based on three wire systems without contact of magnetic resistance is disclosed, the liquid level sensor includes a signal wire harness 1 and an information tube 2, a float 3 is disposed on the information tube 2, a magnet is fixed inside the float 3, a circuit board is disposed in the information tube 2, and a three wire system circuit is printed on the circuit board, the three wire system circuit is composed of a signal output end (OUT), a ground end (GND), a power end (VCC), a resistor string (R1, R2, R3 … … RX), and a magnetoresistive chip sequence (Q1, Q2, Q3 … … QX), wherein an end of the resistor string is connected with the signal output end, a signal pin of each magnetoresistive element in the magnetoresistive chip sequence is connected with resistors in the resistor string in a one-to-one correspondence manner, that is, Q1 is connected with R1, Q2 is connected with R2, and the like, a power pin of each magnetoresistive element is connected with the power end; the signal output end, the grounding end and the power supply end are all connected with the signal wire harness 1.

When the circuit board is used, when the floater 3 is at different positions, the magnetic resistance elements at corresponding positions are triggered to be conducted, the signal wire harness 1 outputs corresponding resistance signals, and therefore the position of the floater 3 is detected. The invention CAN also output different signals such as current, voltage, CAN signals and the like according to the requirements of the using end.

As a preferred embodiment, the liquid level sensor further comprises a top seat 4 for fixing the information pipe 2, the top seat 4 is installed on an engine oil tank, an oil suction pipe 5 and an oil return pipe 6 for supplying oil to an engine of a vehicle are installed on the top seat 4, the oil suction pipe 5 and the oil return pipe 6 are arranged side by side with the information pipe 2, and when the engine works, oil is sucked from the oil suction pipe 5, and redundant oil is guided back to the oil tank from the oil return pipe 6. Still install heating pipe 7 on footstock 4, heating pipe 7 connects the recirculated coolant liquid of vehicle engine, and heating pipe 7 encircles and inhale oil pipe 5 and return oil pipe 6 lower half, and during operation heating pipe 7 is in circulating the engine coolant liquid of high temperature to the oil tank, for fuel heating, is convenient for supply with the use. The liquid level sensor further comprises a buffer tray 8, the buffer tray 8 is used for fixing the bottoms of the oil suction pipe 5, the oil return pipe 6 and the heating pipe 7, and the bottom of the buffer tray 8 is abutted to the bottom of an oil tank, so that the firmness of the liquid level sensor can be increased.

The integrated structure has compact design and small volume, reduces the layout of the pipeline of the whole vehicle and simplifies the installation procedure; in addition, the whole product adopts die-casting aluminum materials and laser welding precision packaging technology, and the water circulation heating pipeline part adopts stainless steel materials, so that the strength and the sealing effect of the product are ensured, the leakage of anti-freezing solution is avoided, the corrosion resistance is strong, and the cleanness of fuel is ensured.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.

Claims

1. The utility model provides a three-wire system linear type liquid level sensor based on magnetic resistance non-contact, liquid level sensor includes signal harness (1) and information pipe (2), be equipped with float (3) on information pipe (2), its characterized in that: a magnet is fixed inside the floater (3), a circuit board is arranged in the information tube (2), a three-wire system circuit is printed on the circuit board and consists of a signal output end, a grounding end, a power supply end, a resistor string and a magneto-resistance chip sequence, wherein the end of the resistor string is connected with the signal output end, the signal pin of each magneto-resistance element in the magneto-resistance chip sequence is correspondingly connected with the resistor in the resistor string one by one, the power supply pin of each magneto-resistance element is connected with the power supply end, and the grounding pin of each magneto-resistance element is connected with the grounding end;

and the signal output end, the grounding end and the power supply end are all connected with the signal wire harness (1).

2. A magnetoresistive non-contact based three-wire linear level sensor as claimed in claim 1, wherein: the liquid level sensor further comprises a top seat (4) used for fixing the information pipe (2), an oil suction pipe (5) and an oil return pipe (6) used for supplying oil to a vehicle engine are mounted on the top seat (4), and the oil suction pipe (5), the oil return pipe (6) and the information pipe (2) are arranged side by side.

3. A magnetoresistive non-contact based three-wire linear level sensor as claimed in claim 2, wherein: the heating pipe (7) is further mounted on the top seat (4), the heating pipe (7) is connected with circulating cooling liquid of a vehicle engine, and the heating pipe (7) surrounds the lower half portions of the oil suction pipe (5) and the oil return pipe (6).

4. A magnetoresistive non-contact based three-wire linear level sensor as claimed in claim 3, wherein: the liquid level sensor further comprises a buffer tray (8), and the buffer tray (8) is used for fixing the bottoms of the oil suction pipe (5), the oil return pipe (6) and the heating pipe (7).