Effect of gear tooth fillet radius on the performance of injection molded Nylon 6/6 gears

Dynamic interaction between contact loads and tooth wear of engaged plastic gear pairs

Study on development of polyamide gears for improvement of load-carrying capacity

http://e-university.tu-sofia.bg/e-publ/files/7932_Applications%20of%20dry%20%EF%AC%81lm%20lubricants%20for%20polymer%20g.pdf

Applications of dry film lubricants for polymer gears

Finite element method model to predict bulk and flash temperatures on polymer gears

Plastic gears have many excellent characteristics which are locking in metallic gears, such as corrosion resistance, self-lubrication, quiet running, and so forth. The meshing behavior of plastic gears is very different from that of metallic gears. Therefore, the life estimation is very difficult for plastic gears. In this paper, generating and growing mechanisms of abnormal wear which appears fatally near the root of plastic tooth are analyzed, and then it is clarified that tooth fractures which take place frequently near pitch point are caused by abnormal wear. Additionally, some methods for extending the life of plastic gears are proposed.

https://www.jstage.jst.go.jp/article/jsme1958/29/251/29_251_1598/_pdf

Development of Plastic Gear for Power Transmission : Abnormal Wear on the Tooth Root and Tooth Fracture near Pitch Point

The plastic gears excel in the self-lubrication, the low noise and others over the steel ones. But they are not suitable for power transmission because of their low load carrying capacity and short lifetime. In the present paper, the power transmission mechanism of the plastic gears is clarified theoretically and experimentally. And then the causes for the melting and the partially large wear which occurs on the tooth surface are analyzed through the mechanism. As a result of these analyses, the plastic gears, whose contact ratio is more than two and whose tooth profile deflected by the load agrees with the normal involute, are recommended in order to increase the load capacity and the life time.

DEVELOPMENT OF PLASTIC GEARS FOR POWER TRANSMISSION : Power Transmission Mechanism of Plastic Gears

As a prevention method of tooth profile change of a nylon gear, which meshes with a steel gear, this paper proposes a profile modification of steel gear. And a reasonable amount of modification is obtained by experiments. From the results, it is clear that the expression of the amount of profile modification Δα (minutes) of steel gear is as follows. Δα = ζ (Tc·T/9.8b) + ξ ζ : Change value of pressure angle change (minutes)/(N·m/m)·s, Tc : Contact period of teeth of nylon gear (second), T : Torque acting on nylon gear (N·m), b : Face width (m), ξ : Basic value of pressure angle change (minutes).

Investigation about the Prevention of Tooth Profile Change of Plastic Gears : 1st Report; Amount of Profile Modification of the Steel Gear, which Meshed with the Nylon Gear

Two prevention methods are proposed in the previous report as the prevention methods of tooth profile change in the course of operation of a nylon gear which transmits the power. And their effect is confirmed by experiments. In this report as a method simpler than those methods, a plus profile shifting of nylon gear is proposed. In the plus profile shifted gear, the tooth thickness of tooth flank increases and the tooth is less liable to deflect. Meanwhile the sliding of tooth is large. In this report the abrasion of tooth of nylon gear is investigated under several profile modification coefficients and this method is examined to see how useful it is as the prevention method of tooth profile change.

Jiasun Shi

Papers

Development of Plastic Gear for Power Transmission : Abnormal Wear on the Tooth Root and Tooth Fracture near Pitch Point

DEVELOPMENT OF PLASTIC GEARS FOR POWER TRANSMISSION : Power Transmission Mechanism of Plastic Gears

Investigation about the Prevention of Tooth Profile Change of Plastic Gears : 1st Report; Amount of Profile Modification of the Steel Gear, which Meshed with the Nylon Gear

Investigation about the Prevention of Tooth Profile Change of Nylon Gears : 3rd Report, Wear and Tooth Profile Change in Profile Shifted Nylon Gears