Mike Krzyzewski is really a famous coach of Dream Team. She has coached north america men's basketball team for some time, that's clinched numerous medals for his country. Following Londonfl jerseys supplyn Olympic was over, Krzyzewski told The Associated Press that this game will be his final one as national coach, a job he's held for seven years. He had left open the possibility of swomen nfl jerseystaying with the team beyond the London Games, when practice on Saturday said these will be his last Olympics.When asked if he was sure, Krzyzewski didn't hesitate before again saying, "yecheap nfl jerseys wholesales," this will be his last game "If we could win it, then it might be three major championships in a row, i always do not know when that has been done because we haven't usually won http://govoriotkrito.bg/libs/nflcn08.htmthe globe championships," Krzyzewski said. "It becomes an enormous thing for the program." Whatever, he's an awesome coach. His achievement are going to be remembered by the country.cheap nfl jerseys
新闻动态 News
搜索 Search
你的位置:首页 > 新闻动态 > 行业新闻

小型继电器的外形和工作原理

2014/1/8 20:17:37点击:

小型继电器的外形和工作原理

外形:尺寸20×10×15.5mm(长×宽×高) ; 小型1c接点继电器; 可以5A开闭(NO接点);小型继电器 确保耐冲击高压8KV 小型继电器具体型号: PQ1A-3V PQ1A工作原理:继电器有各种各样的结构形式,最常用的是双金属片式结构,图!"为热继电器的结 构原理图。双金属片!是小型继电器用两种不同线膨胀系数的金属片,小型继电器通过机械辗压在一起制成的,一端 固定,另一端为自由端。当双金属片的温度升高时,由于两种金属的线膨胀系数不同,小型继电器所以它 将弯曲。小型继电器热元件串接在电动机定子绕组中,小型继电器电动机绕组电流即为流过热元件的电流。当电 动机正常运行时,热元件产生的热量虽能使双金属片!弯曲,但不足以使继电器动作;当电动 机过载时,热元件产生的热量增大,小型继电器使双金属片弯曲位移量增大,经过一段时间后,双金属片弯 曲推动导板,并通过补偿双金属片与推杆'将触点(和)分开,触点(和)为热继电器串 于接触器线圈回路的动断触点,小型继电器断开后使接触器失电,接触器的动合触点断开电动机等负载回 路,保护了电动机等负载。 补偿双金属片可以在规定范围内( +,-"+,)补偿环境温度对热继电器的 影响。如果周围环境温度升高,双金属片向 左弯曲程度加大,然而补偿双金属片也向 左弯曲,使导板与补偿双金属片之间距离 保持不变,故继电器特性不受环境温度升高 的影响,反之亦然。有时可采用欠补偿,使 补偿双金属片向左弯曲的距离小于双金 属片!因环境温度升高向左弯曲的变动值, 以便在环境温度较高时,热继电器动作较 快,更好地保护电动机。 小型继电器调节旋钮''是一个偏心轮,它与支撑 件'!构成一个杠杆,转动偏心轮,即可改变图!"热继电器的结构原理 补偿双金属片与导板的接触距离,小型继电器从而 达到调节整定动作电流值的目的。此外,小型继电器靠调节复位螺钉.来改变动合静触点的位置使热 继电器能工作在手动复位和自动复位两种工作状态。调试手动复位时,在故障排除后需按下 按钮'+才能使动触点(恢复与静触点)相接触的位置参考资料: