﻿ 基于激光测距的节温器检测
 光学仪器  2020, Vol. 42 Issue (2): 14-19 PDF

Thermostat detection based on laser ranging technology
ZHANG Zhaohai, GAO Hongbo, ZHOU Xianpeng, ZHANG Yinfeng, WANG Xin
Air Force Early Warning Academy, Wuhan 430000, China
Abstract: Thermostat, as the automatic temperature control device of the cooling system of the engine, has an important effect on the engine. In order to solve the problems in traditional mechanical thermostat performance detection, such as data deficiency, low measuring accuracy, high security risk, and inconvenience to operate. We find a non-contact way to get the real time lift of the thermostat based on laser ranging technology, and get the synchronous temperature by the temperature sensor. In this way, we can obtain the complete data of the thermostat. This method is an accurate, safe, convenient, and non-contact way, temperature measurement accuracy is 0.1 °C, and lift measurement accuracy is 1 mm. We setup a thermostat detection system and verify it by experiments with the Jiefang J6 thermostat. The result shows this system can detect the performance of thermostat accurately and efficiently, such as temperature stability, performance consistency, and fault diagnosis criterion. It is applicable to ordinary engine maintenance as well as educational practices.
Key words: thermostat    laser ranging    performance detection    non-contact detection

1 节温器工作原理

 图 1 发动机节温器工作原理 Figure 1 Working principle of engine thermostat
2 检测原理 2.1 激光测距原理

2.2 节温器阀升程测量原理

 图 2 节温器阀升程测量原理 Figure 2 Measurement principle of thermostat valve lift

 $\Delta {d_{\rm{t}}} = {D_0} - {D_{\rm{t}}}$ (1)

 ${S_{\rm{h}}} = 2{d_{\rm{h}}} \cdot {n_1}$ (2)
 $\varepsilon = 2{d_{\rm{h}}} \cdot ({n_1} - {n_0})$ (3)

3 检测系统

 图 3 节温器检测系统结构示意图 Figure 3 Structure diagram of thermostat testing system

 图 4 节温器检测系统实物图 Figure 4 Photo of thermostat testing system
4 实验及分析 4.1 节温器升程-温度曲线及温度稳定性测量

 图 5 解放J6节温器升程–温度关系曲线（单个节温器温度稳定性测量拟合） Figure 5 Relation curve between lift and temperature of Jiefang J6 thermostat（fitting from temperature stability test of single thermostat）

4.2 同一型号节温器性能一致性测量

 图 6 解放J6节温器升程–温度关系曲线（多个节温器性能一致性测量拟合） Figure 6 Relation curve between lift and temperature of Jiefang J6 thermostat（fitting from performance consistency test of multiple thermostats）
4.3 故障节温器的判断

5 结论

 [1] 牟红雨, 金研, 郝世杨, 等. 汽车发动机冷却系统检测与维修研究[J]. 时代汽车, 2018(7): 192–193. DOI:10.3969/j.issn.1672-9668.2018.07.087 [2] 于增信. 汽车发动机构造、原理与维修[M]. 北京: 机械工业出版社, 2014. [3] 王佳. 发动机冷却系统节温器的原理与检修[J]. 时代农机, 2016, 43(8): 14, 16. [4] 聂永涛, 张志伟, 陈绍志. 汽车发动机节温器的检修[J]. 轻型汽车技术, 2016(1/2): 66–67. [5] 陈家瑞, 马天飞. 汽车构造[M]. 北京: 人民交通出版社, 2006. [6] 谭晓瑞. 相位式激光测距系统设计[D]. 太原: 中北大学, 2016. [7] 郑大青, 陈伟民, 陈丽, 等. 一种基于相位测量的快速高精度大范围的激光测距法[J]. 光电子•激光, 2015, 26(2): 303–308. [8] 郁道银, 谈恒英. 工程光学[M]. 4版. 北京: 机械工业出版社, 2016. [9] 郑玉祥, 陈良尧. 近代光学[M]. 北京: 电子工业出版社, 2011. [10] ARICI O, JOHNSON J H, KULKARNI A J. The vehicle engine cooling system simulation part 1-model development[R]. Houghton: SAE, 1999. [11] 孟令宾, 李二倩, 田茂再. 基于鞍点逼近的二项抽样下优势比的置信区间构造[J]. 数理统计与管理, 2017, 36(1): 85–102.