DEVELOPMENT OF HIGH-SPEED PRECISION LASER SCANNER WITH LOW POWER CONSUMPTION

近年来，激光扫描仪电机的转速一直在迅速提高。但是，提高转速会导致多边形镜的风阻功率损失很大。这就导致了机壳温升过大、扫描电机功耗过大等问题。在本研究中，我们提出了一种新的降低激光扫描镜面宽功耗的方法。这种方法利用了鱼骨气体滑动轴承的泵送效应。该轴承可用作粘性真空泵，将空气从扫描仪外壳内部抽出。由于外壳内的压力几乎降至真空，因此在该扫描仪中，风阻功率损失几乎为零。我们用真空泵制造了这种类型的激光扫描仪电机。然后，测量了该激光扫描电机的风阻功率损失、壳体内压、鱼骨轴承泵送效应、噪声水平和电机转速波动(抖动)等各项性能。此外，还研究了带真空泵的鱼骨轴承的承载特性。可以清楚地看到，在30000rpm时，所提出的扫描仪的功率损耗约为传统扫描仪的一半，并且所研制的扫描仪电机的抖动优于传统扫描仪电机。结果表明，该方法对减小激光扫描镜的风损是非常有效的。

Recently, rotational speed of a laser scanner motor has been rapidly increasing. But an increase in the rotational speed induces large windage power loss of a polygon mirror. This causes various problems such as considerable temperature rise of a housing and large power consumption of a scanner motor.In this research, we proposed a newly developed reduction method of wihdage power loss of a laser scanner mirror. This method uses the pumping effect of a herring-bone gas journal bearing. This bearing can function as a viscous vacuum pump and pump the air out from the inside of the scanner housing. Since the pressure in the housing reduces to almost a vacuum, the windage power loss becomes to be nearly zero in this scanner. We manufactured this type of laser scanner motor with a vacuum pump. Then, we measured various performances of this laser scanner motor such as the windage power loss, the inner pressure of the housing, the pumping effect of the herring-bone journal bearint, the noise level and the fluctuation of motor rotational speed (jitters). Furthermore, bearing characteristics of herring-bone bearing with a vacuum pump were investigated. It was clearly seen that the power loss of the proposed scanner was about a half of that of the conventional one at 30000rpm and the jitters of the developed scanner motor was superior to the conventional scanner motor. As a result, it can be concluded that the proposed method is very effective for reducing the windage power loss of a laser scanner mirror.