1、回转式风机和罗茨风机的原理很不一样，罗茨风机依靠的是利用两个叶形转子在气缸内作相对运动来压缩和输送气体的回转压缩机。而回转式风机是靠汽缸内偏置的转子偏心运转，并使转子槽中的叶片之间的容积变化将空气吸入、压缩、吐出。在运转中利用鼓风机的压力差自动将润滑送到滴油嘴，滴入汽缸内以减少摩擦及噪声，同时可保持汽缸内气体不回流。
1. The principle of rotary fan is very different from that of Roots blower. Roots blower relies on a rotary compressor that compresses and transports gas by using the relative motion of two blade rotors in the cylinder. The rotary fan is operated eccentrically by the offset rotor in the cylinder, and the volume change between the blades in the rotor slot will suck in, compress and spit out the air. During operation, the pressure difference of the blower is used to automatically send lubrication to the oil drip nozzle and drip it into the cylinder to reduce friction and noise, while keeping the gas in the cylinder from flowing back.
2、在结构上，回转式风机由鼓风机本体、空气室、空气过滤器、滴油嘴、底座（兼油箱）、电机六部份组成。回转风机主体是制造压缩空气的心脏部件，采用汽缸偏心方式，加工精度高，因此也是运转时噪音较小的原因之一。罗茨风机的结构就比较简单，由机壳、墙板、叶轮、油箱、消声器五大部分组成的。
2. In structure, the rotary fan is composed of six parts: blower body, air chamber, air filter, drip nozzle, base (also used as oil tank) and motor. The main body of the rotary fan is the heart part for manufacturing compressed air. It adopts the cylinder eccentric method and has high processing accuracy. Therefore, it is also one of the reasons for low noise during operation. The structure of Roots blower is relatively simple, which is composed of five parts: casing, wallboard, impeller, oil tank and muffler.

3、他们的压力范围是不一样的，回转风机的风量只能去到10立方每分钟，压力是0.5公斤，所以使用的范围比较窄。而罗茨风机的压力流量范围都比他要广。
3. Their pressure range is different. The maximum air volume of the rotary fan can only reach 10 cubic meters per minute, and the maximum pressure is 0.5 kg, so the range of use is relatively narrow. The pressure and flow range of Roots blower is wider than that of others.
4、性不同，回转式鼓风机将润滑油滴入汽缸内时，会有微量的油进入水体，而且排气口会有油雾出现，如果是运用在食品行业，更多人会选择罗茨风机。因为罗茨鼓风机的内腔不需要润滑油，只需对风机齿轮添加齿轮油，而回转式风机在运转中为减少摩擦和噪声，会利用压力差自动将润滑油送到滴油嘴，滴入汽缸内，因此罗茨鼓风机输送的气体是干净的，无污染。
4. The environmental protection is different. When the rotary blower drips lubricating oil into the cylinder, a small amount of oil will enter the water body, and there will be oil mist at the exhaust port. If it is used in the food industry, more people will choose Roots blower. Because the inner chamber of Roots blower does not need lubricating oil, only the gear oil needs to be added to the fan gear. In order to reduce friction and noise during the operation of rotary fan, the pressure difference will automatically send lubricating oil to the drip nozzle and drip into the cylinder, so the gas delivered by Roots blower is clean and pollution-free.