CN110702188A - Device and method for measuring oil quantity of oil tank of zero-turning-radius mower - Google Patents
Device and method for measuring oil quantity of oil tank of zero-turning-radius mower Download PDFInfo
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- CN110702188A CN110702188A CN201910953869.0A CN201910953869A CN110702188A CN 110702188 A CN110702188 A CN 110702188A CN 201910953869 A CN201910953869 A CN 201910953869A CN 110702188 A CN110702188 A CN 110702188A
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- plate
- oil tank
- capacitor
- oil
- voltage
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/26—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields
- G01F23/263—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/26—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields
- G01F23/263—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors
- G01F23/266—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors measuring circuits therefor
Abstract
The invention discloses a device and a method for measuring the oil quantity of an oil tank of a zero-turning-radius mower, wherein the device comprises an oil tank, a capacitor plate and a control module, a rectangular groove is formed in the bottom of a cavity of the oil tank, insulating materials are coated on the side wall and the bottom wall of the rectangular groove, the upper plate of the capacitor plate is arranged in the rectangular groove in a vertically movable mode, the lower plate of the capacitor plate is embedded in the bottom wall of the rectangular groove, a sealed space is formed between the upper plate and the lower plate of the capacitor plate and the side wall of the rectangular groove, and the capacitor plate is connected to the control module. According to the invention, the output digital signal is acquired and processed through voltage feedback generated by the change of the oil quantity in the oil tank, and the corresponding relation curve of the oil output quantity and the voltage is calculated and fitted, so that the real-time oil quantity of the oil tank in the driving process of the mower can be obtained through the corresponding relation curve, the measurement is convenient, and the working efficiency is high.
Description
Technical Field
The invention relates to an oil tank oil mass measuring technology, in particular to a device and a method for measuring the oil mass of an oil tank of a zero-turning-radius mower.
Background
Zero turning radius mowers are often applied to complex work environments such as slopes and depressions, and therefore overturning and rolling are prone to occur, and injuries and deaths of drivers are caused. The center of mass position of the zero-turning-radius mower is one of important factors influencing the transverse and longitudinal stability of the mower. The mass center of the oil tank can affect the mass center of the whole mower, particularly the critical position of the mower when the mower rolls, wherein the mass center of the oil tank is particularly affected by the mass of the oil tank. Therefore, the oil quantity monitoring of the oil tank of the mower is very important.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide a device and a method for measuring the oil quantity of an oil tank of a zero-turning-radius mower, and solves the problem of oil quantity monitoring of the oil tank of the mower. The oil quantity of the oil tank is accurately measured, the measurement cost is low, and the voltage converted by the capacitance value changes along with the change of the oil quantity, so that the oil quantity detection is accurate and convenient, and the working efficiency is high.
The technical scheme is as follows: the invention discloses a measuring device for the oil quantity of an oil tank of a zero-turning-radius mower, which comprises an oil tank, a capacitor plate and a control module, wherein a rectangular groove is formed in the bottom of a cavity of the oil tank, insulating materials are coated on the side wall and the bottom wall of the rectangular groove, the upper plate of the capacitor plate is arranged in the rectangular groove in a vertically movable mode, the lower plate of the capacitor plate is embedded in the bottom wall of the rectangular groove, a sealing space is formed between the upper plate and the lower plate of the capacitor plate and the side wall of the rectangular groove, and the capacitor plate is connected to the control module.
Furthermore, the upper pole plate and the lower pole plate of the capacitor pole plate are both connected with a mower battery for power supply.
Furthermore, the upper pole plate and the lower pole plate of the capacitor pole plate are sealed through insulating materials. The insulating material may be epoxy or plastic, etc.
Furthermore, the control circuit of the control module comprises a voltage conversion circuit and a voltage acquisition circuit; the voltage conversion circuit is connected between the capacitor plate and the voltage acquisition circuit to realize the conversion of capacitor voltage between the capacitor plate and the voltage acquisition circuit; the voltage acquisition circuit is connected with the output end of the voltage conversion circuit and acquires the output digital quantity.
Further, the voltage conversion circuit includes two operational amplifiers AR1 and AR2, a capacitor C, resistors R1 and R2; the inverting input end of the operational amplifier AR1 is connected with a constant voltage power supply through a capacitor C, the non-inverting input is grounded, and a feedback loop is connected with the two ends of a capacitor plate and then connected with the inverting input end; the output end of the operational amplifier AR1 is connected with the inverting input end of the operational amplifier AR2 through a resistor R1, the non-inverting input end of the operational amplifier AR2 is grounded, the feedback loop is connected back to the inverting input end through a resistor R2, and the output end is connected with the voltage acquisition circuit.
Further, the voltage acquisition circuit comprises a comparator C, D/A converter, a counter, a pulse source, a control gate G and an output register; the non-inverting input end of the comparator C is connected with the output end of the capacitance-voltage conversion circuit, and the inverting input end of the comparator C is connected with the output end of the D/A converter; the pulse source is connected with the clock signal input end of the counter through the control gate G, and the output end of the counter is connected with the input end of the D/A converter and is connected with the output register.
The invention also provides a method for measuring the oil quantity of the oil tank of the zero-turning-radius mower, which comprises the following steps: in the running process of the mower, the oil quantity in the oil tank is reduced to reduce the liquid level pressure of the upper pole plate of the capacitor pole plate, the closed space formed by the upper pole plate and the lower pole plate of the capacitor pole plate arranged in the oil tank is increased, and the upper pole plate of the capacitor pole plate moves upwards to reduce the capacitance; the voltage output by the voltage conversion circuit increases along with the reduction of the capacitance of the capacitor plate; and finally, acquiring the change of the output signal in real time through a voltage acquisition circuit, fitting a corresponding relation curve of the voltage and the oil quantity of the oil tank, and obtaining the corresponding oil quantity along with the output signal through the curve.
Compared with the prior art, the technical scheme of the invention has the following beneficial effects:
(1) the liquid level pressure of the oil quantity is converted into voltage by arranging a sealed space, so that the influence of liquid shaking, concave convex surface and other reasons on the measurement precision is avoided;
(2) the oil quantity state of the oil tank can be known at any time by the measuring device when the mower runs, and the oil quantity is ensured to meet the requirement of smooth running of the mower;
(3) high-cost electronic control units and sensors are not used, and the cost of oil consumption detection is reduced.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic view of the internal structure of the fuel tank;
FIG. 3 is a schematic diagram of a voltage conversion circuit;
fig. 4 is a schematic diagram of a voltage acquisition circuit.
DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
The invention is further described below with reference to the following figures and examples:
as shown in fig. 1 and 2, the device for measuring the oil mass of the oil tank of the zero-turning-radius mower comprises an oil tank 1, a capacitor plate 2 and a control module 3, wherein a rectangular groove 4 is formed in the bottom of a cavity of the oil tank 1, an upper plate of the capacitor plate 2 is vertically movably arranged in the rectangular groove 4, a lower plate of the capacitor plate 2 is embedded in the bottom wall of the rectangular groove 4, the upper plate and the lower plate of the capacitor plate 2 and the side wall of the rectangular groove 4 form a sealed space, the side wall and the bottom wall of the rectangular groove 4 are both coated with an insulating material, because the space between the two plates is isolated from the outside, the capacitor plate 2 is connected to the control module 3, the side wall and the bottom wall of the rectangular groove 4 are insulated to prevent the two plates from being short-circuited, the insulating material can be epoxy resin and the like, and thus the distance between the upper plate and the lower plate of the capacitor plate 2 can, which corresponds to a capacitance of variable value;
the upper pole plate and the lower pole plate of the capacitor pole plate 2 are both connected with a mower battery 5 for power supply, and the upper pole plate and the lower pole plate of the capacitor pole plate 2 are both sealed by insulating materials, wherein the insulating materials can be epoxy resin or plastic and the like;
the control circuit of the control module 3 comprises a voltage conversion circuit and a voltage acquisition circuit; the voltage conversion circuit is connected between the capacitor plate 2 and the voltage acquisition circuit to realize the conversion of the capacitor voltage between the capacitor plate 2 and the voltage acquisition circuit; the voltage acquisition circuit is connected with the output end of the voltage conversion circuit and acquires the output digital quantity.
As shown in fig. 3, the voltage conversion circuit includes two operational amplifiers AR1 and AR2, a capacitor C, and resistors R1 and R2; the inverting input end of the operational amplifier AR1 is connected with a constant voltage power supply through a capacitor C, the non-inverting input is grounded, and the feedback loop is connected with the two ends of the capacitor plate and then connected with the inverting input end; the output end of the operational amplifier AR1 is connected with the inverting input end of the operational amplifier AR2 through a resistor R1, the non-inverting input end of the operational amplifier AR2 is grounded, the feedback loop is connected back to the inverting input end through a resistor R2, and the output end is connected with the voltage acquisition circuit;
as shown in fig. 4, the voltage acquisition circuit includes a comparator C, D/a converter, a counter, a pulse source, a control gate G, and an output register; the non-inverting input end of the comparator C is connected with the output end of the capacitance voltage conversion circuit, and the inverting input end of the comparator C is connected with the output end of the D/A converter; the pulse source is connected with the clock signal input end of the counter through the control gate G, and the output end of the counter is connected with the input end of the D/A converter and is connected with the output register.
A method for measuring the oil quantity of an oil tank of a zero-turning-radius mower comprises the following steps: during the driving process of the mower, the oil quantity in the oil tank 1 is reduced to cause the liquid level pressure of the upper pole plate of the capacitor pole plate 2 to be reduced, the closed space formed by the upper pole plate and the lower pole plate of the capacitor pole plate 2 arranged in the oil tank 1 is increased, the upper pole plate of the capacitor pole plate 2 moves upwards, and the capacitance is related to the cross section area and the pole plate distance of the capacitor pole plate 2 according to the formula
Wherein epsilon represents a dielectric constant, a represents a cross-sectional area, and d represents a plate pitch; when the upper electrode plate moves upwards, the distance between the electrode plates is increased, and the capacitance is reduced;
in the voltage conversion circuit, as known from the first operational amplifier AR1 circuit, a constant voltage power supply continuously charges the capacitor C and the capacitor plate 2, and as known from the concept of virtual short and virtual break, the voltage at the inverting input terminal and the non-inverting input terminal of the operational amplifier AR1 is 0, as represented by the formula Q ═ C · U, where Q represents the charge amount of the capacitor plate, C represents the capacitance,u represents the voltage across the capacitor, the output voltage of the operational amplifier AR1 can be represented by the formula C (U)0-0)＝c·(0-Ui) Wherein C represents the capacitance of the fixed capacitor plate, U0Representing the input voltage, c representing the capacitance of the capacitor plate, UiRepresenting the output voltage, the output voltage
Wherein "-" indicates that the output voltage polarity is opposite to the input voltage polarity, after passing through the inverting amplifier AR2, the output voltage polarity is the same as the input voltage polarity, the output voltage increases with the decrease of the capacitance of the capacitor plate, and the voltage output by the voltage conversion circuit increases with the decrease of the capacitance of the capacitor plate;
as shown in fig. 4, the voltage at the two ends of the capacitor is output after passing through the conversion circuit, the output voltage enters the voltage acquisition circuit to be converted, the voltage Ux to be converted enters the non-inverting input end of the comparator, the analog voltage quantity Uy converted by the D/a converter enters the inverting input end of the comparator to be compared with Ux, if Ux > Uy, the output of the comparator is high level, otherwise, the output is low level; when the pulse is high level, the pulse from the pulse source is applied to the clock signal input end CLK of the counter through the control gate G, and the counter starts to count up. Since the number in the counter changes continuously during the conversion, an output register is provided at the output for this purpose, the state of the output register being used as the final output signal; and finally, acquiring the change of the output signal in real time through a voltage acquisition circuit, listing the output signal and the specific oil quantity according to the same time, fitting a corresponding relation curve of the voltage and the oil quantity of the oil tank, and obtaining the corresponding oil quantity along with the output signal through the curve.
Claims (7)
1. The utility model provides a measuring device of zero turning radius lawn mower oil tank oil mass which characterized in that: including oil tank, electric capacity polar plate and control module, the cavity bottom of oil tank is equipped with the rectangle recess, the lateral wall and the diapire of rectangle recess have all been coated with insulating material, the last polar plate of electric capacity polar plate can set up in the rectangle recess with reciprocating, and the bottom plate of electric capacity polar plate is embedded in the diapire of rectangle recess, and the last polar plate of electric capacity polar plate and the lateral wall of bottom plate and rectangle recess form sealed space, the electric capacity polar plate is connected to control module.
2. The device for measuring the oil content in the oil tank of the zero-turning-radius mower according to claim 1, wherein: and the upper pole plate and the lower pole plate of the capacitor pole plate are both connected with a mower battery for power supply.
3. The device for measuring the oil content in the oil tank of the zero-turning-radius mower according to claim 1, wherein: and the upper pole plate and the lower pole plate of the capacitor pole plate are both sealed by insulating materials.
4. The device for measuring the oil content in the oil tank of the zero-turning-radius mower according to claim 1, wherein: the control circuit of the control module comprises a voltage conversion circuit and a voltage acquisition circuit; the voltage conversion circuit is connected between the capacitor plate and the voltage acquisition circuit to realize the conversion of capacitor voltage between the capacitor plate and the voltage acquisition circuit; the voltage acquisition circuit is connected with the output end of the voltage conversion circuit and acquires the output digital quantity.
5. The device for measuring the oil content in the oil tank of the zero-turning-radius mower according to claim 4, wherein: the voltage conversion circuit comprises two operational amplifiers AR1 and AR2, a capacitor C, and resistors R1 and R2; the inverting input end of the operational amplifier AR1 is connected with a constant voltage power supply through a capacitor C, the non-inverting input is grounded, and a feedback loop is connected with the two ends of a capacitor plate and then connected with the inverting input end; the output end of the operational amplifier AR1 is connected with the inverting input end of the operational amplifier AR2 through a resistor R1, the non-inverting input end of the operational amplifier AR2 is grounded, the feedback loop is connected back to the inverting input end through a resistor R2, and the output end is connected with the voltage acquisition circuit.
6. The device for measuring the oil content in the oil tank of the zero-turning-radius mower according to claim 4, wherein: the voltage acquisition circuit comprises a comparator C, D/A converter, a counter, a pulse source, a control gate G and an output register; the non-inverting input end of the comparator C is connected with the output end of the capacitance-voltage conversion circuit, and the inverting input end of the comparator C is connected with the output end of the D/A converter; the pulse source is connected with the clock signal input end of the counter through the control gate G, and the output end of the counter is connected with the input end of the D/A converter and is connected with the output register.
7. The method for measuring the oil quantity of the oil tank of the zero-turning-radius mower is characterized by comprising the following steps of: in the running process of the mower, the oil quantity in the oil tank is reduced to reduce the liquid level pressure of the upper pole plate of the capacitor pole plate, the closed space formed by the upper pole plate and the lower pole plate of the capacitor pole plate arranged in the oil tank is increased, and the upper pole plate of the capacitor pole plate moves upwards to reduce the capacitance; the voltage output by the voltage conversion circuit increases along with the reduction of the capacitance of the capacitor plate; and finally, acquiring the change of the output signal in real time through a voltage acquisition circuit, fitting a corresponding relation curve of the voltage and the oil quantity of the oil tank, and obtaining the corresponding oil quantity along with the output signal through the curve.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910953869.0A CN110702188A (en) | 2019-10-09 | 2019-10-09 | Device and method for measuring oil quantity of oil tank of zero-turning-radius mower |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910953869.0A CN110702188A (en) | 2019-10-09 | 2019-10-09 | Device and method for measuring oil quantity of oil tank of zero-turning-radius mower |
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| CN110702188A true CN110702188A (en) | 2020-01-17 |
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