CN102003248A - Method for measuring lubricating oil level and sensor - Google Patents

Method for measuring lubricating oil level and sensor Download PDF

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Publication number
CN102003248A
CN102003248A CN 201010529788 CN201010529788A CN102003248A CN 102003248 A CN102003248 A CN 102003248A CN 201010529788 CN201010529788 CN 201010529788 CN 201010529788 A CN201010529788 A CN 201010529788A CN 102003248 A CN102003248 A CN 102003248A
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heating wire
oil level
lubricating oil
resistance
wire
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CN 201010529788
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CN102003248B (en )
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刘桂兴
沈刚
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江阴众和电力仪表有限公司
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Abstract

The invention relates to a method for measuring lubricating oil level and a lubricating oil level sensor. The oil level is measured through the impedance change of a straight electric heating wire, namely the electric heating wire is excited by alternating current or direct current to emit heat, and the temperatures of the electric heating wire in two media, namely air and lubricating oil, are different, so the resistance of the electric heating wire changes with the position of the oil, and the lubricating oil level is determined according to the change law of the resistance. In the lubricating oil level sensor, the straight electric heating wire and a power amplifier for providing the alternating current or direct current to heat the electric heating wire are arranged on a framework; amplitude stabilized alternating current is adopted; and a sine wave generator outputs an amplitude stabilized signal at a certain frequency at the front end of the power amplifier, so the pressure drop of the two ends of the electric heating wire changes with the oil level linearly and quasilinearly, the resistance of the straight electric heating wire correspondingly changes with the pressure drop of the two ends of the corresponding electric heating wire, and the resistance of the electric heating wire is measured.

Description

一种润滑油位测量的方法及传感器 A lubricating oil level measuring method and sensor

技术领域 FIELD

[0001] 本发明涉及一种润滑油位测量的方法及传感器。 [0001] The present invention relates to a method and a lubricating oil level sensor measurements. 是机械设备润滑油位测量装置。 Machinery and equipment lubricating oil level measuring device. 背景技术 Background technique

[0002] 测量润滑油位置的传感器种类较多,大多设备采用间接测量的方式。 [0002] more types of sensors measuring the position of the lubricating oil, most of the indirect way of measuring equipment. 较常规的都带有一浮球驱动测量传感器或单点测量,因浮球受安装空间限制或润滑油粘度大等因素测量不可靠,单点测量无法形成连续的在线监测。 Are presented with a more conventional float measuring sensor drive or single point measurement, due to space constraints or float mounted by large factors of lubricating viscosity measurements are not reliable, single point measurement can not form a continuous online monitoring. 安装简便可连续测量的润滑油位置传感器具有广泛的市场前景。 The lubricant is easy to install position sensors continuously measure has broad market prospect.

发明内容 SUMMARY

[0003] 本发明的目的是提出一种润滑油位测量的方法及检测机械设备润滑油油位装置, 即润滑油油位传感器,可以实现小量程高精度连续测量,结构简单体积小,可应用于小型设备和复杂的润滑油液位测量环境。 [0003] The object of the present invention is to propose a method of detecting the mechanical equipment and the oil level measuring device of a lubricating oil level, i.e., the oil level sensor can achieve small-scale continuous measurement with high accuracy, small size of simple structure, can be applied small devices and sophisticated lubricant level measurement environment.

[0004] 本发明的技术解决方案是:润滑油位测量的方法,其特征是通过一直线状的电热丝的阻抗变化测量油位,即通过一交流电流或直流电流激励电热丝发热,电热丝在空气和润滑油两种介质中的温度存在差异,因此电热丝的电阻也随着油的位置而变化,根据电阻的变化规律来确定润滑油位。 [0004] The technical solution of the invention is: A method of measuring the lubricating oil level, characterized in that the impedance is varied by the heating wire has a linear measuring the oil level, i.e. excitation by an electric heating wire alternating current or direct current, electric wire there is a difference in air temperature and the lubricating oil in the two media, so that the resistance heating wire also varies as the position of the oil, lubricating oil level is determined according to the variation of resistance.

[0005] 润滑油位传感器,在一骨架上设有直线状电热丝,由功率放大器提供交流电流或直流电流(如IOOmA交流电流)对电热丝加热,使用交流电流时采用稳幅交流电流时频率固定在某一频率,频率范围不限(如1Hz),功率放大器前端由一正弦波发生器输出某一频率如IHz频率的稳幅信号,设有测量电热丝的电阻的电路,电热丝的电阻大小对应润滑油位的高低,加热后根据油和空气两种介质散热差改变了电热丝的电阻,因此电热丝两端的压降随着油位的高低线性或准线性变化,根据相应的电热丝两端的压降大小,直线状电热丝的电阻亦相应有大小,通过测量电热丝的电阻,在交流测量时通过整流滤波转换成直流电压信号来测量电阻,根据需要也可以变换成电流信号。 When [0005] the lubricating oil level sensor is provided with a linear heating wire on a bobbin, there is provided an alternating current or a direct current (e.g., alternating current IOOmA) by a wire heating power amplifiers, leveled using alternating current AC current frequency fixed resistors certain frequency, the frequency range is not limited (e.g., 1Hz), the front end of the power amplifier output by a frequency of the sine wave generator as a steady increase IHz signal frequency, a circuit for measuring the resistance heating wire, the heating wire corresponding to the magnitude of the level of lubricating oil level, the oil and air heating in accordance with the difference between the two media change heat resistance heating wire, so the voltage drop across the heating wire with low oil level linear or quasi-linear change, depending on the respective heating wire the size of the voltage drop across the resistance heating wire also linearly corresponding in size, by measuring the resistance heating wire, when measuring AC converter into a DC voltage by rectifying the filtered signal to the measuring resistor, according to need may be converted into a current signal. 本发明还可以用于其它绝缘且安全的油品的油位传感器。 The present invention may also be used other insulating oil level sensor and safe oil. 电热丝两端的压降随着油位的高低线性或准线性变化(可以经过CPU校准),因电热丝在空气中散热要比在油中散热差,如散热差则电热丝的热阻大,相应的电热丝两端的压降大,通过测量电热丝的电阻,在交流测量时通过整流滤波转换成直流电压信号来测量电阻,根据需要也可以变换成电流信号。 The voltage drop across the heating wire with the oil level of a linear or quasi-linear variation (can be calibrated via CPU), due to the heating wire in the air heat dissipation than the difference in oil, such as poor heat dissipation of the high thermal resistance of the heating wire, corresponding large voltage drop across the heating wire, by measuring the resistance heating wire, when measuring AC converter into a DC voltage by rectifying the filtered signal to the measuring resistor, according to need may be converted into a current signal. 本发明还可以用于其它绝缘且安全的油品的油位传感器。 The present invention may also be used other insulating oil level sensor and safe oil.

[0006] 电热丝均为电阻丝,常用的如康铜丝、铬铜丝;相应的电阻与润滑油位结果的对应关系是:电阻愈小,润滑油油位愈低。 [0006] The resistance wire heating wire are commonly used as constantan wire, copper-chromium; corresponding resistance correspondence between bit result lubricants are: the smaller the resistance, the lower the oil level.

[0007] 所述直线状电热丝是一根直线状电热丝或平行固定一对直线电热丝,平行固定一对直线电热丝是一根电热丝,绕制在一骨架上。 The [0007] linear is a linear heating wire or heating wires fixed to a pair of linear parallel heating wires are fixed in parallel pair of linear electric wire is an electric wire, wound on a bobbin. 绕制在一骨架上,直线状电热丝采用平行固定一对直线电热丝较好,单根电热丝还需要导线构成回路,也可以采取N根平行绕制的电热丝,当然,采用偶数根在接线上更加方便。 Wound on a bobbin, using a linear heating wire fixed in parallel is preferably a pair of linear heating wire, a single wire heating wire required circuit configuration, can also take the N of parallel heating wires wound, of course, employed in even number easier on the terminal. [0008] 本发明的有益效果是:本发明提出的润滑油位置传感器,通过精度高且最容易实现的的电阻测量可连续测量润滑油位置(只需要在输出端口不断取出信号即可),相比传统单点测量方法更直观,实时信号可远传到终端仪表或管理系统。 [0008] Advantageous effects of the present invention is that: the position sensor lubricant proposed by the present invention, high precision and the easiest to implement resistance measurement can be continuously measured lubricants position (just need to keep out a signal to the output port), with more intuitive than conventional single point measuring method, real-time signal to a remote terminal may be a meter or system management. 较小体积和先进的测量方式可应用在复杂的环境。 Smaller volume and advanced measurement can be applied in a complex environment. 本发明其结构简单,可靠性高,对终端仪表电路的要求低,现场安装维护容易,使用方便。 The present invention is of simple structure, high reliability, low demand meter circuit terminal, installation and maintenance, easy to use.

附图说明 BRIEF DESCRIPTION

[0009] 图1是本发明结构示意图。 [0009] FIG. 1 is a structural diagram of the present invention.

[0010] 图2是本发明测量电路框图(原理图)。 [0010] FIG. 2 is a block diagram of a measurement circuit of the present invention (schematic diagram).

具体实施方式 detailed description

[0011] 本发明的具体实施方式如下: [0011] embodiment of the present invention are as follows:

传感器原理是(图1)通过骨架上固定一电热丝1,连接到金属防护外壳内功能电路,外壳上有电缆引出装置,安装固定传感器采用螺纹螺钉均可,电热丝部分根据油箱深度制定长度。 Is the sensor principle (FIG. 1) fixed to the skeleton by a heating wire 1, connected to the metal shielding function circuit within the housing, the cable lead-out means, the sensor fixed on the housing can be threaded screws, the length of the heating wire partially developed according to the depth of the tank.

图2是传感器测量电路原理图,在一骨架上平行固定一电热丝,由功率放大器提供IOOmA交流电流对电热丝加热,频率固定在1HZ,功率放大器前端由一正弦波发生器输出IHZ的稳幅信号,加热后根据油和空气两种介质散热差改变了电热丝的电阻,因此电热丝两端的压降随着油位的高低线性变化,再通过整流滤波转换成直流信号,根据需要也可以变换成电流信号。 FIG 2 is a schematic circuit diagram of sensor measurement, a heating wire fixed in parallel on a backbone, alternating current provided by the power amplifier to IOOmA wire heating, 1HZ fixed frequency, a sine wave generator from the front end of the power amplifier output leveled IHZ signal, after heating oil and air in accordance with the difference between the two media change heat resistance heating wire, so the voltage drop across the heating wire varies linearly with the height of the oil level, and then converted into a DC signal by the rectifier filter, if necessary, can be converted a current signal.

[0012] 本发明的润滑油传感器采取新颖的设计,把电热丝的热阻变化变换成液位测量信号,变送后输出工业标准的(Γ20πιΑ)交流电流信号,本发明解决了润滑油连续测量的技术空白,小体积简单结构应用范围较广。 [0012] The sensor of the present invention the lubricating oil taken novel design, the change in resistance of the heating wire into a level measurement signal, the output of the industry-standard transmitter (Γ20πιΑ) alternating current signal, the present invention solves the continuous measurement of the lubricating oil technology gaps, simple structure and small size wider range of applications.

1、取合金电阻丝IOOmm固定在绝缘骨架上,两端用电阻脚焊接后拉直,悬空在骨架体上,骨架上刻有标尺,试验传感器直流电阻18. 2欧姆,输入电压10VDC,恒定电流100mA, 润滑油sae30装入透明量杯中,环境温度25C°,在暴露在空气中测量传感器两端电压为: 2.45VDC,完全插入装有润滑油中侧得为:1. 87 VDC,按每IOmm插入润滑油中分别测得传感器两端电压(表1)。 1, taken IOOmm alloy resistance wire is fixed to the insulating housing, and rear ends of the feet by resistance welding straightened, hanging in the frame body, a scale engraved on the bobbin, DC resistance of the test sensor 18.2 ohms, 10VDC input voltage, a constant current 100mA, lubricants sae30 into a transparent cup, the ambient temperature 25C °, measured after exposure to air as the voltage across the sensor: 2.45VDC, full insertion side with a lubricating oil obtained is:. 1 87 VDC, per IOmm insert the lubricating oil measured voltage across the sensor, respectively (table 1).

[0013] 2、由功率放大器提供IOOmA交流电流对电热丝加热,频率固定在1HZ,功率放大器前端由一正弦波发生器输出IHZ的稳幅信号,交流电压峰峰值20VAC,按每IOmm插入润滑油中分别测得传感器两端电压(表1)。 [0013] 2, the alternating current provided by the power amplifier to IOOmA wire heating, 1HZ fixed frequency, the power amplifier by a distal fixed amplitude sinusoidal signal generator IHZ alternating voltage peak 20VAC, lubricants inserted per IOmm respectively measured voltage across the sensor (table 1).

[0014] 3、本发明的润滑油位传感器,电热丝置于需要测量的油的容器内,设有正弦波发生电路和功率发生器或恒流发生器,功率发生器或恒流发生器的输出连接电热丝,电阻的测量电路是整流电路经信号放大电路和电压测量电路即(图中的变送电路)至测量的输入输出端口。 [0014] 3, lubricating oil level sensor of the present invention, the heating wire is placed within the oil vessel to be measured with a sine wave generating circuit or a constant current generator and a power generator, the power generator or a constant current generator heating wire output connection, the resistance measuring circuit is a rectifier circuit and a signal amplifying circuit via the voltage measurement circuit i.e. (transmission circuit in the drawing) to measure the input and output ports.

[0015] 4、所述正弦波发生电路是常规电路,可以是常规的阻容振荡电路,也可以采用微处理器产生的正弦波发生电路。 [0015] 4, the sine wave generating circuit is a conventional circuit, may be a conventional RC oscillator circuit, the microprocessor may be generated sine wave generating circuit. 功率发生器或恒流发生器是恒电流放大电路(如共基极放大电路),功率发生器或恒流发生器的输出连接电热丝,电阻的测量电路是对电阻丝两端的电压测量来实现的,通过二级管桥式整流电路和经信号放大电路对电阻二端电压进行测量,图中的变送电路至测量的输入输出端口,输入输出端口接一微处理器,可根据电压的测量值可由微处理器进行定标(确定一定温度下电阻与电压的对应曲线)。 A power generator or a constant current generator is a constant current amplifying circuit (e.g. common base amplifier circuit), the output of the power generator or a constant current generator is connected to the heating wire, the resistance of the measurement circuit is the voltage measured across the resistance wire to achieve enlarged by the diode bridge rectifier circuit and a signal circuit via the two-terminal resistance measurement voltage, the transmission circuit to the FIG measured input and output ports, an output port connected to a microprocessor input, the voltage may be measured according to scaling value by a microprocessor (corresponding to the curve determining resistor and a voltage at a certain temperature).

[0016] 5、如采用直流电源,对电热丝上的电阻测量取样可通过一电桥来实现。 [0016] 5. The DC power supply, measuring the resistance heating wire can be realized by a sampling bridge. 通过常规的电桥可以高精度的测量电阻。 May be measured by a conventional resistance bridge with high accuracy.

[0017]表 1 [0017] TABLE 1

插入深度匪 测量电压VDC 测量电压VAC0 2. 451 1. 73310 2. 407 1. 70220 2. 347 1. 65930 2. 287 1. 61740 2. 220 1. 57050 2. 163 1. 52960 2. 101 1. 48570 2. 041 1. 44380 1. 977 1. 39890 1. 922 1. 359100 1. 871 1. 323 Bandit insertion depth measured voltage VDC measured voltage VAC0 2. 451 1. 73310 2. 407 1. 70220 2. 347 1. 65930 2. 287 1. 61740 2. 220 1. 57050 2. 163 1. 52960 2. 101 1. 48 570 2.041 1.44380 1.977 1.39890 1.922 1.871 1.323 1.359100

根据测量结果,电热丝两端略有线性误差,通过分析后发现是固定电热丝的金属焊脚引起的,实际应用中两端预留5mm可避免测量误差。 According to the measurement result, both ends of the heating wire slightly linearity error is found by the analysis of a metal heating wire fixed to the fillet caused by the practical application of both ends of the reservation 5mm measurement errors can be avoided.

[0018] 图中所述直线状电热丝1是平行固定一对直线电热丝,偶数根均是可取的方案, 平行固定一对直线电热丝是一根电热丝,绕制在一长条状骨架上。 [0018] FIG straight in the heating wire 1 is fixed to a pair of linear parallel heating wires even number are preferable embodiment, a parallel pair of linear heating wire is fixed is a heating wire, wound in a long strip backbone on. 绕制在一骨架的直线状电热丝可以置于一套管2内,图中其它标志:传感器外壳3、引出线4、润滑油5。 Wound heating wire in a linear backbone may be placed inside a sleeve 2, FIG other flags: sensor housing 3, lead wire 4, the lubricating oil 5.

Claims (6)

  1. 1.润滑油位测量的方法,其特征是通过一直线状的电热丝的阻抗变化测量油位,即通过一交流电流或直流电流激励电热丝发热,电热丝在空气和润滑油两种介质中的温度存在差异,因此电热丝的电阻也随着油的位置而变化,根据电阻的变化规律来确定润滑油位。 1. A method of measuring the lubricating oil level, characterized in that the straight line through the measured impedance variation oil heating wire, the heating wire that is excited by an alternating current heating or direct current, electric wire and air lubricating the two media in differences in temperature, so that the resistance heating wire also varies as the position of the oil, lubricating oil level is determined according to the variation of resistance.
  2. 2.润滑油位传感器,其特征是在一骨架上设有直线状电热丝,设有功率放大器提供交流电流或直流电流对电热丝加热,使用交流电流时采用稳幅交流电流,功率放大器前端由一正弦波发生器输出某一频率的稳幅信号,设有测量电热丝的电阻的电路,电热丝的电阻大小对应润滑油位的高低,加热后根据油和空气两种介质散热差改变了电热丝的电阻,因此电热丝两端的压降随着油位的高低线性或准线性变化,根据相应的电热丝两端的压降大小,直线状电热丝的电阻亦相应有大小,通过测量电热丝的电阻。 2. The lubricating oil level sensor, characterized in that the heating wire has a linear shape on a backbone, with the power amplifier provides alternating current or direct current wire heating using alternating current is leveled using the alternating current, the front end amplifier a fixed amplitude sine wave generator output signal of a certain frequency, a circuit measuring the electrical resistance heating wire, resistance heating wire size corresponding to the level of the lubricating oil level, after heating the heat differential is changed in accordance with oil and air heating two mediums resistance wire, and therefore the voltage drop across the heating wire with the oil level of a linear or quasi-linear change, according to the size of the voltage drop across the respective heating wire, resistance heating wire also linearly corresponding in size, by measuring the heating wire resistance.
  3. 3.根据权利要求2所述的润滑油位传感器,其特征是在交流测量时通过整流滤波转换成直流电压信号来测量电阻。 3. The lubricating oil level sensor according to claim 2, wherein the conversion is measured by rectifying and smoothing AC voltage into a DC signal measuring resistor.
  4. 4.根据权利要求2所述的润滑油位传感器,其特征是所述直线状电热丝是一根直线状至N根电热丝,N是整数,平行绕制在一骨架上。 4. The lubricating oil level sensor according to claim 2, characterized in that the heating wire is a straight linear electrical heating wires to N, N being an integer, parallel wound on a bobbin.
  5. 5.根据权利要求2所述的润滑油位传感器,其特征是所述一对直线电热丝绕制在一骨 The lubricating oil level sensor according to claim 2, wherein said pair of linear heating wire wound in a bone
  6. 6.根据权利要求2所述的润滑油位测量传感器,其特征是电热丝置于需要测量的油的容器内,设有正弦波发生电路和功率发生器或恒流发生器,功率发生器或恒流发生器的输出连接电热丝,电阻的测量电路是整流电路经信号放大电路和电压测量电路即至测量的输入输出端口。 The lubricating oil level measurement sensor according to claim 2, characterized in that the heating wire is placed within the oil vessel to be measured with a sine wave generating circuit or a constant current generator and a power generator, the power generator or a constant current generator is connected to the output of the heating wire, the resistance of the measurement circuit via a rectifier circuit and a signal amplifying circuit to measure the voltage measuring circuit i.e. input and output ports.
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CN102444445A (en) * 2011-10-26 2012-05-09 潍柴动力股份有限公司 Engine oil liquid level measuring device and method thereof
CN102620796A (en) * 2012-04-10 2012-08-01 无锡盛邦电子有限公司 Electronic engine oil liquid level sensor
CN104677460A (en) * 2015-03-23 2015-06-03 上海理工大学 Level detection device
CN106289445A (en) * 2015-06-03 2017-01-04 江阴市全盛自动化仪表有限公司 Current transmitter for measuring oil level
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CN106289445A (en) * 2015-06-03 2017-01-04 江阴市全盛自动化仪表有限公司 Current transmitter for measuring oil level
CN106499464A (en) * 2016-11-22 2017-03-15 天津梦琪科技有限公司 Detection device for engine oil amount early warning and display system thereof

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