One type of lobe pump is actually the cycloidal lobe pump, which is not very popular and has great disadvantages, but it is an important part of those special industries or special products. Today Ace Pumps is here to tell you about the structure and working principle of the cycloidal lobe pump.
The construction of the cycloidal lobe pump is as follows.
The pump is made up of a pair of internal rotors and pump bodies, pump covers, etc. The inner rotor is an external drive gear, and its tooth profile is an external cycloid; the outer rotor is an internal drive gear, and the tooth profile is an arc-shaped curve. The inner and outer rotors have different centres of rotation and are eccentric to each other e. The number of teeth of the inner rotor can be eight, 10, etc. The outer rotor has one more tooth than the inner rotor. The more teeth the inner rotor has, the lower the oil pulsation will be. In general, the inner rotor of the cycloidal lobe pumps commonly used in automatic transmissions have all 10 teeth.
The cycloidal lobe pump works as follows.
When the diesel engine is running, it drives the rotor inside and outside the petrol pump in the same direction. The inner rotor has positive teeth, while the outer rotor is driven one tooth per revolution slower than the inner rotor. The tooth profile of the inner rotor and the outer rotor is a pair of conjugate point curve, which ensures that when the petrol pump is running, no matter what position the inner and outer rotor turns to, all the teeth are in the case of the teeth together, i.e. there is always a point on the tooth profile curve of each tooth of the inner rotor and the tooth profile curve of the outer rotor touching, thus producing the same number of working chambers in the middle of the inner rotor and outer rotor as the number of teeth of the inner rotor. When the rotor rotates clockwise, the capacity of each working cavity on the right side of the centre line of the inner and outer rotor increases from small to partial vacuum pumps, which suck in the gear oil from the inlet hole; the capacity of each working cavity on the left side of the centre line of the inner and outer rotor decreases from large to small, which discharges the gear oil from the oil outlet. This is the whole process of the oil valve of the cycloidal lobe pump.
The exhaust volume of a cycloidal lobe pump lies in the number of teeth of the inner rotor, the tooth profile, the tooth width and the eccentricity of the inner and outer rotor. The greater the number of teeth, the tooth type, the tooth width and the eccentricity, the greater the exhaust volume.
Some people say that the cycloidal lobe pump and the internal gear pump, only the tooth type is not the same, this kind of understanding is incorrect, in fact, their differences are very big. The first is the number of teeth of the internal drive gear and the transmission gear are not the same; the second is the oil transport method is not the same, one is the internal drive gear and transmission gear mutually generated oil transport cavity oil transport, the other is the internal drive gear and transmission gear must have the crescent groove to produce oil transport cavity.
Warm reminder: The above is the introduction to the structure and working principle of the cycloidal lobe pump. If you need to have a specific cycloidal lobe pump you can contact Ace Pumps, Ace will produce the corresponding cycloidal lobe pump according to your needs.