CN106404124B

CN106404124B - Liquid level sensor

Info

Publication number: CN106404124B
Application number: CN201610397417.5A
Authority: CN
Inventors: 杨杰; 别亮亮; 李蓉
Original assignee: Guangdong University of Technology
Current assignee: Guangdong University of Technology
Priority date: 2016-06-06
Filing date: 2016-06-06
Publication date: 2023-05-09
Anticipated expiration: 2036-06-06
Also published as: CN106404124A

Abstract

The present invention provides a liquid level sensor comprising: a resistor pad base; the resistor disc is fixedly arranged on the resistor disc base; the bracket is provided with a sliding contact piece which can slide on the resistor piece; a lever arm mounted on the bracket; a float mounted on the lever arm; the cover body is used for forming an enclosing space, the enclosing space is provided with an opening relative to the liquid level, the opening is used for enabling the lever arm to freely move, and the resistor disc and the sliding contact disc are at least partially located in the enclosing space. The liquid level sensor of the invention can still maintain the accuracy of measurement after long-time use.

Description

Liquid level sensor

Technical Field

The invention relates to a liquid level sensor, in particular to a liquid level sensor for measuring the height of an oil level in a vehicle oil tank.

Background

In automotive instruments, the indication of the amount of oil is of considerable importance, whereas the indication of the amount of oil depends on a level sensor. Among the prior art, there is a liquid level sensor to drive the lever arm through the float, and the lever arm drives the sliding contact piece that sets up on the support again and slides on the resistance card to change liquid level information into resistance change information, rethread signal circuit and output interface are with liquid level signal output to the instrument, in order to let people acquire liquid level information.

However, the sliding contact piece is contacted with the resistor piece for a long time and is influenced by factors such as oil component difference, impurities and the like, and after the liquid level sensor is used for a long time, the contact of the sliding contact piece and the resistor piece is changed, so that the output resistance value deviates from the standard resistance value, the output electric signal representing the liquid level value is changed, and finally, the pointer cannot accurately reflect the change of the liquid level.

Disclosure of Invention

In order to overcome the above-mentioned difficulty, the present invention aims to provide a liquid level sensor, which can reduce or avoid the influence of gasoline on a sliding contact piece and a resistance piece, so that the liquid level sensor can still maintain the accuracy of measurement after long-time use.

The present invention provides a liquid level sensor comprising: a resistor pad base; the resistor disc is fixedly arranged on the resistor disc base; the bracket is provided with a sliding contact piece which can slide on the resistor piece; a lever arm mounted on the bracket; a float mounted on the lever arm; the cover body is used for forming an enclosing space, the enclosing space is provided with an opening relative to the liquid level, the opening is used for enabling the lever arm to freely move, and the resistor disc and the sliding contact disc are at least partially located in the enclosing space.

Preferably, the cover is integrally formed.

Preferably, the liquid level sensor further comprises a cover body, a connecting arm and a shell, wherein the connecting arm is connected with the cover body and the shell, and the cover body is mounted on the cover body.

Preferably, the portable electronic device further comprises a cover body, a connecting arm and a shell, wherein the connecting arm is connected with the cover body and the shell, the cover body is mounted on the shell, and the shell and the cover body jointly form the enclosing space.

Preferably, the cover is detachably mounted on the housing.

Preferably, the cover is integrally formed with the housing.

Preferably, the cover has a top body, a side body and a front body; the resistor disc and the sliding contact disc are close to the top surface body.

Preferably, the resistor disc base is bent to form a first horizontal portion and a first vertical portion, the bracket is bent to form a second horizontal portion and a second vertical portion corresponding to the resistor disc, the resistor disc is located on the first horizontal portion, and the sliding contact is arranged on the second horizontal portion.

Preferably, the liquid level sensor further comprises a guide rail for assisting in mounting and positioning of the resistor disc base.

According to the liquid level sensor, the contact time of the resistance sheet and the sliding contact sheet with gasoline is reduced, and even the resistance sheet and the sliding contact sheet are not contacted with the gasoline in a manner of forming a surrounding space through the cover body. Compared with the prior art, the contact between the sliding contact sheet and the resistor sheet in the prior art can be changed to cause the output resistance value to deviate from the standard resistance value, and the liquid level sensor can still maintain the measurement accuracy after long-time use.

Drawings

FIG. 1 is a schematic view showing a liquid level sensor according to a first embodiment of the present invention installed in a gasoline tank;

FIG. 2 is an exploded view of the fluid level sensor shown in FIG. 1;

FIG. 3 is a cross-sectional view of the fluid level sensor shown in FIG. 1;

FIG. 4 is a schematic view of a liquid level sensor according to a second embodiment of the present invention;

FIG. 5 is an exploded view of the fluid level sensor shown in FIG. 4;

FIG. 6 is a schematic view of the enclosure shown in FIG. 4;

FIG. 7 is an exploded view of a fluid level sensor according to a third embodiment of the present invention;

FIG. 8 is a schematic view of the internal structure of the housing assembly shown in FIG. 7;

FIG. 9 is a schematic diagram of a combination of the resistor plate, resistor plate base, slip contact, bracket, lever arm of the level sensor of FIG. 7.

Description of the reference numerals

Cover 10 attachment arm 20

Lever arm 3 free section 31 intermediate section 32

Indication section 33 front flat wall 41 of housing 4

Guide rail 5, 5 'blocking block 6, 6' ramp surface 61

Resistor pad base 7 resistor pad 15 first horizontal portion 71

First vertical portion 72 supports 8 and sliding contacts 9

A second horizontal part 81 and a second vertical part 82 of the fixed clamping block 80

Front body 21 and rear body 22 of cover 2

Side body 23 top body 24

Float 12 encloses and covers space 13

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The liquid level sensor of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 to 3 are schematic views of a first embodiment.

As shown in fig. 1, the liquid level sensor of the present invention is installed in a gasoline tank, and has a float 12 fixed to a lever arm 3. The position of the floater 12 is changed along with the change of the liquid level of the gasoline, so that the lever arm 3 is driven to deflect, and the deflection of the lever arm 3 causes the resistance to change and reflect the resistance to the instrument, so that people acquire the liquid level information.

As shown in fig. 2, the liquid level sensor includes a cover 10, a connecting arm 20, and a substantially cylindrical housing 4 from top to bottom, the cover 10 being fixed to an upper surface of the gasoline tank, the connecting arm 20 being fixedly connected to the cover 10 and the housing 4. The housing 4 has a front flat wall 41. The front flat wall 41 is provided with a pair of guide rails 5 and a blocking block 6, and the blocking block 6 is positioned between the guide rails 5.

The liquid level sensor further comprises a resistor disc base 7, a resistor disc 15, a sliding contact disc 9, a bracket 8, a lever arm 3, a cover body 2 and a floater 12.

The resistor 15 is fixedly mounted on the resistor base 7, and the bracket 8 is rotatably mounted on the resistor base 7. Referring to fig. 3, rotation of the lever arm 3 rotates the bracket 8 about the central axis i-i. The support 8 is provided with a sliding contact piece 9, and the sliding contact piece 9 is elastically abutted with the resistor piece 15. When the bracket 8 rotates relative to the resistor disc base 7, the sliding contact 9 slides on the resistor disc 15, so that the resistor is changed.

Two pairs of fixing clamping blocks 80 are provided on the bracket 8 for clamping the lever arm 3 fixed in a cylindrical state, whereby the lever arm 3 is detachably mounted on the bracket 8. The lever arm 3 consists of three sections, namely a free section 31 fixedly connected to the float 12, an indicator section 33 in line with the extension direction of the support 8 and a middle section 32 connecting the former two. The indicator section 33 mates with the fixed clamp block 80.

When the resistor disc base 7, the resistor disc 15, the sliding contact disc 9, the bracket 8 and the lever arm 3 form a combined body, the combined body slides to the upper part of the front flat wall surface 41 from bottom to top through the guide rail 5, and the blocking block 6 is provided with a slope surface 61 (see fig. 3), so that the combined body can gradually transition until being positioned above the blocking block 6, but the top surface of the blocking block 6 is perpendicular to the front flat wall surface 41, so that the combined body cannot fall down.

The cover 2 is mounted on the front flat wall 41 of the housing 4 such that a housing space 13 is formed between the cover 2 and the front flat wall 41. In this embodiment, the cover 2 is composed of four faces, namely a top face 24, two side faces 23 and a front face 21, which are shaped like a cuboid, and the rear face corresponding to the front flat wall 41 is absent, and the bottom face is absent. When the cover 2 is mounted on the front flat wall 41, only the bottom end of the corresponding enclosure 13 is not sealed for flexible movement of the lever arm 3.

When the gasoline tank is filled with oil, the gas is filled in the enclosing space 13 formed in the cover body 2, the cover body 2 is only provided with the opening at the bottom end, the position of the opening at the bottom end is plugged by the oil, so that the gas cannot be discharged, at the moment, although the liquid level of the gasoline tank gradually rises, the liquid level in the cover body 2 is kept unchanged, thus, the gas is sealed in the enclosing space 13 enclosed by the cover body 2 and the front plane wall 41 together, the resistor 15 and the sliding contact 9 are positioned in the enclosing space 13 filled with air, thereby avoiding the possibility that the resistor 15 and the sliding contact 9 are soaked in gasoline, avoiding the corrosion of the resistor 15 and the sliding contact 9 by the gasoline, avoiding the influence of impurities in the oil on the resistor 15 and the sliding contact 9, and keeping the contact sensitive and accurate.

Of course, in other embodiments, if the opening of the bottom end of the cover 2 is too upward, the enclosure space 13 formed between the cover 2 and the front flat wall 41 is not large enough, so that the resistor 15 and the sliding contact 9 are partially located in the enclosure space 13, so that when the gasoline tank is filled with gasoline, it is still possible for the resistor 15 and the sliding contact 9 to have the lower portion located in the gasoline soak, which is still within the spirit of the present invention. Thus, the arrangement of the enclosing space reduces the degree of soaking the resistor disc 15 and the sliding contact sheet 9 in gasoline, reduces the influence of impurities in the oil on the resistor disc 15 and the sliding contact sheet 9, and ensures that the sliding of the sliding contact sheet 9 on the resistor disc 15 is influenced by gasoline as little as possible so as to keep the sensitivity and accuracy of contact as much as possible.

Therefore, in the present embodiment, the top surface body 24 of the cover body 2 is positioned as close as possible to the upper end of the housing 4, and thus, the resistor 15 and the slide contact 9 are mounted as close as possible upward. In this way, it is possible to ensure that the enclosure space 13 formed in the housing 2 is more reliable, the less likely the resistive sheet 15 and the wiping sheet 9 will come into contact with the petrol when the petrol starts to be consumed. In this way, the application function of the enclosure 13 is more ensured.

Fig. 4 to 6 are schematic views of a second embodiment.

The second embodiment differs from the first embodiment in the structure and position of the cover. As shown in fig. 5 and 6, in the second embodiment, the cover 2' is composed of five faces, including a front body 21, a rear body 22, two side bodies 23 and a top body 24, resembling a rectangular parallelepiped, with only the bottom body being absent to form an opening relative to the liquid surface, adapted to the free movement of the lever arm 3. The rear body is attached to the front flat wall 41.

The guide rail 5' and the stopper 6' are not provided on the front flat wall surface 41 of the housing 4, but the guide rail 5' and the stopper 6' are provided on the inner wall surface of the cover 2', in this embodiment, on the wall surface of the rear body 22 facing the enclosure space. As shown in fig. 4, the entire cover 2' is fixedly mounted on the cover 10. As shown in fig. 6, arrow a indicates the sliding-in direction of the resistor pad base 7.

In the first embodiment, since the cover 2 and the front flat wall 41 of the housing need to be fitted together to form the enclosure space 13 with a common surrounding wall, the fitting installation needs to be careful about sealability; however, the cover 2 'of the second embodiment does not need to form a housing space together with the front flat wall surface 41 of the housing, and the cover 2' of the second embodiment is integrally formed, avoiding the trouble of installation with the housing 4. In addition, the cover body 2 'is directly mounted on the cover body 10, and the mounting position of the cover body 10 is the top surface of the oil tank, so that the enclosing space formed inside the cover body 2' is almost at the highest position inside the oil tank, so that the possibility of soaking in gasoline is avoided or reduced to the greatest extent by the resistor sheet 15 and the sliding contact sheet 9.

Fig. 7 to 9 are schematic views of a third embodiment.

As shown in fig. 7, the liquid level sensor includes a cover 10, a connecting arm 20, and a substantially cylindrical housing 4 from top to bottom, the cover 10 being fixed to an upper surface of the gasoline tank, the connecting arm 20 being for fixedly connecting the cover 10 and the housing 4. The liquid level sensor further comprises a resistor pad base, a resistor pad 15, a sliding contact pad 9, a bracket, a lever arm 3, a cover body 2 and a floater 12.

As shown in fig. 8 and 9, the cover 2 has a top surface body 24, two side surface bodies 23, and a front surface body 21; the resistor disc base is bent to form a first horizontal part 71 and a first vertical part 72, the bracket is bent to form a second horizontal part 81 and a second vertical part 82 corresponding to the resistor disc base, the resistor disc 15 is positioned on the first horizontal part 71, and the sliding contact 9 is arranged on the second horizontal part 81; the first horizontal portion 71 and the second horizontal portion 81 are each abutted against the top surface body 24, in other words, the first horizontal portion 71 and the second horizontal portion 81 are each parallel to the top surface body 24; the second vertical portion 82 corresponding to the bracket is correspondingly mounted on the first vertical portion 72 of the resistor pad base. It will be appreciated that the axis of rotation of the bracket relative to the resistor disc base is located on the second vertical portion 82.

When the lever arm 3 rotates, the second vertical part 82 of the bracket is driven to rotate, the second vertical part 82 and the second horizontal part 81 are integrally formed, and the rotation of the second vertical part 82 necessarily drives the rotation of the second horizontal part 81; however, the first horizontal portion 71 of the resistor pad base is fixedly mounted on the top surface body 24 of the cover body 2, and the first horizontal portion 71 of the resistor pad base is integrally formed with the first vertical portion 72, and therefore, the first horizontal portion 71 and the first vertical portion 72 remain stationary. Thus, the resistor 15 is stationary and the trolley 9 is dynamic.

In summary, the liquid level sensor of the present invention adopts the cover body to form the enclosed space, the enclosed space is opposite to the opening of the liquid level, when the liquid level rises in the oiling process, the opening is blocked by the oil, the gas in the enclosed space is enclosed inside, so that the relative movement of the sliding contact piece and the resistor piece occurs in the enclosed space filled with the gas, and therefore, the liquid level sensor is not soaked by the gasoline, the influence of the gasoline can be reduced, and the sensitive contact is maintained, so that the accurate measurement value is obtained.

It should be understood that the cover may be not only integrally formed with the housing, but also removably mounted to the housing; or the cover body is independently formed into a single-opening enclosure body.

It should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the scope of the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted equally without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A liquid level sensor, comprising:

a resistor pad base;

the resistor disc is fixedly arranged on the resistor disc base;

the bracket is provided with a sliding contact piece which slides on the resistor piece;

a lever arm mounted on the bracket;

a float mounted on the lever arm;

wherein the resistor disc base, the resistor disc, the sliding contact disc, the bracket and the lever arm form a combination body; and

the cover body is used for forming an enclosing space, the enclosing space is provided with an opening relative to the liquid level, the opening is used for enabling the lever arm to freely move, and the resistor disc and the sliding contact piece are at least partially positioned in the enclosing space;

the shell is connected with the cover body and provided with a front flat wall surface, a pair of guide rails and a blocking block are arranged on the front flat wall surface, and the blocking block is positioned between the guide rails; the blocking block is provided with a slope surface; the combination body slides to the upper part of the front flat wall surface through the guide rail, and the combination body is positioned above the blocking block.

2. The fluid level sensor of claim 1, further comprising a cover, a connecting arm connected to the cover and the housing, the housing being mounted to the housing, the housing and the housing collectively forming the enclosure.

3. The fluid level sensor of claim 1, wherein the cover is removably mounted to the housing.

4. The fluid level sensor of claim 1, wherein the cover is integrally formed with the housing.

5. The fluid level sensor of claim 1, wherein the housing has a top body, a side body, and a front body; the resistor disc and the sliding contact disc are close to the top surface body.