Design And Manufacturing For Micro Three-gear Pump With Logix Gears And Its Flow Characteristics

At present, the research and development of high performance gear-drive hydraulic power components, especially the high pressure, high efficient hydraulic pump, has become one of the research topics at home and abroad. Gear pump has many advantages, such as simple structure, small volume, light weight, easy manufacturing, easy to maintenance. Involute gear and single-pump feed technology are difficult to satisfy the requirements of high-homogeneous-medium and low-loss situation. Developing a high flow pulsation performance micro pump is one of the trend of hydraulic power components. This paper is committed to developing such a micro pump.Firstly, in view of the traditional gear pump in miniaturization and flow pulsation problem, Logix gear and double-pump confluence technology is put forward respectively.With analysising the structure of the Logix gear tooth profile, it can lower undercutting tendency by taking an advantage of Logix gear that has less tooth, then miniaturize the pump.With analysising double-pump confluence technology, the flow pulsation can be reduced by phase compensation each other with double-pump confluence technology.Secondly, double-pump confluence technology is realized by using three-gear pump structure. Three gear pump has a less gear than two single pumps, which can reduce volume. Discussing the relationship of two brunch’s phase difference and the number of center gear. With double-pump confluence technology, compensating two brunch’s phase each other can reduce the flow pulsation.Afterwards, in order to avoid difficulties in direct modeling one-off drawing of Logix gear tooth profile, this paper draw tooth profile of the Logix gear tooth profile with iteration programming, then exrude it. On this basis, with selecting parameters, such as the modulus, this paper design gear and pump case. The pump has been manufactured by micro-milling in this study.In the end, this paper develops a pressure pulsation test device for three-gear pump with Logix gears.. Based on pressure pulsation test and comparison between the traditional gear pump and Logix gear pump, this paper verify the feasibility of test method and correctness of the predictions in flow pulsation of Logix gear pump.