In recent years, a new type of gear named Logix gea r was developed. Actually, the tooth profile of this new type of gear is composed of lots of micro-segment involute curves, and on the profile, there exist lots of p...In recent years, a new type of gear named Logix gea r was developed. Actually, the tooth profile of this new type of gear is composed of lots of micro-segment involute curves, and on the profile, there exist lots of points, which their relative curvatures are equal to zero. This can result in the sliding coefficient smaller between two meshed Logix gears, and the mesh ch aracteristic becomes almost rolling transmission from sliding transmission accor dingly. So, this new type of gear has lots of advantages such as higher contact intensity, longer useful life and can easily realize power transfer of bigger tr ansmission ratio than standard involute gear. Study results showed that the cont act fatigue strength is 3 times larger, the bend fatigue strength is 2.5 times l arger, and the minimum tooth number can be decreased to 3, much smaller than tha t of standard involute gear. In this paper, following studies had been done: 1) The formation principle of Logix gear tooth profile was studied. The theoreti cal models describing the geometrical formations of this type of gear and its re lative Logix rack had been deduced. 2) While cutting a Logix gear, its tooth profile is decided by its normal tooth profile of Logix rack. Besides the basic parameters of standard involute gear, L ogix rack has its own specific parameters such as preliminary pressure angle, re lative pressure angle, and preliminary referential circle radius etc. So, the in fluence of connatural parameters of Logix rack on the tooth profile of Logix gea r had been farther studied. Reasonable selection for these parameters had been d iscussed. 3) Several kinds of transition curves for gear’s tooth profile had been introdu ced, its selection used by Logix gear had been described, and also its mathemati cal description model had been deduced. 4) The mesh theories of Logix gears had been developed. It had been proved that the transmission performance between Logix gears coincides with E-W theorem as that of ordinary standard involute gears. The formula calculating superposition coefficient was deduced according to its definition. Different from standard inv olute gears, the parameter of gear number has no effect on the superposition coe fficient of the Logix gears. Accordingly, bigger ratio transmission can be acqui red by means of decreasing the gear number, and its minimum gear number can be r eached to 3, much smaller than the minimum gear number of ordinary standard invo lute gear: 14~17. This is very important to realize the miniaturization of prod uction design. 5) The CAD special software was developed to design all kinds of Logix gears, an d a solid design example was offered. To sum up, by means of above study, the system info about Logix gear had been de veloped and enriched. This has most significant impact on its widely promotion a nd practical application, on the improvement of carrying capacity, miniaturizati on, and life of kinetic transmission products.展开更多
THE pine trees of the Huangshan Mountains surprise many people because of their different artistic and expressive shapes. All through the ages many people have carved poems at the top of the Taishan Mountains. However...THE pine trees of the Huangshan Mountains surprise many people because of their different artistic and expressive shapes. All through the ages many people have carved poems at the top of the Taishan Mountains. However, my favorite spot is the Heavenly Pond on top of the Changbai Mountains. The Changbai Mountains are located in Antu County in the Yanbian Korean Autonomous Prefecture of Jilin Province.展开更多
SOON we’ll celebrate the new year. According to Hangzhou tradition, every family will cook a hot dish for this feast which will include shredded winter bamboo shoots, hotbed chives, shredded meat and smoked bean curd...SOON we’ll celebrate the new year. According to Hangzhou tradition, every family will cook a hot dish for this feast which will include shredded winter bamboo shoots, hotbed chives, shredded meat and smoked bean curd. In addition, some families will also cook a dish of "展开更多
EVER since ancient times Shanghai people have pursued beauty. The Shanghai History Museum, mounted an exhibition entitled "Spectacular Garments, Cultural Relics and Documents of Modern Shanghai" which certai...EVER since ancient times Shanghai people have pursued beauty. The Shanghai History Museum, mounted an exhibition entitled "Spectacular Garments, Cultural Relics and Documents of Modern Shanghai" which certainly proved this point. This exhibit showed that throughout Shanghai’s long history, dress and personal adomment have been important to the residents. During the展开更多
A middle aged woman from Shandong Province showed us her embroidered shirt. The shirt was made of chiffonelle, with embroidered flowers on the front. The shirt was very cool and comfortable, beautiful and dignified, a...A middle aged woman from Shandong Province showed us her embroidered shirt. The shirt was made of chiffonelle, with embroidered flowers on the front. The shirt was very cool and comfortable, beautiful and dignified, and priced reasonably. These cotton shirts are mostly sold overseas. Shandong Weifang Woolen Clothing Factory is a union of 15 township-owned enterprises in several cities展开更多
文摘In recent years, a new type of gear named Logix gea r was developed. Actually, the tooth profile of this new type of gear is composed of lots of micro-segment involute curves, and on the profile, there exist lots of points, which their relative curvatures are equal to zero. This can result in the sliding coefficient smaller between two meshed Logix gears, and the mesh ch aracteristic becomes almost rolling transmission from sliding transmission accor dingly. So, this new type of gear has lots of advantages such as higher contact intensity, longer useful life and can easily realize power transfer of bigger tr ansmission ratio than standard involute gear. Study results showed that the cont act fatigue strength is 3 times larger, the bend fatigue strength is 2.5 times l arger, and the minimum tooth number can be decreased to 3, much smaller than tha t of standard involute gear. In this paper, following studies had been done: 1) The formation principle of Logix gear tooth profile was studied. The theoreti cal models describing the geometrical formations of this type of gear and its re lative Logix rack had been deduced. 2) While cutting a Logix gear, its tooth profile is decided by its normal tooth profile of Logix rack. Besides the basic parameters of standard involute gear, L ogix rack has its own specific parameters such as preliminary pressure angle, re lative pressure angle, and preliminary referential circle radius etc. So, the in fluence of connatural parameters of Logix rack on the tooth profile of Logix gea r had been farther studied. Reasonable selection for these parameters had been d iscussed. 3) Several kinds of transition curves for gear’s tooth profile had been introdu ced, its selection used by Logix gear had been described, and also its mathemati cal description model had been deduced. 4) The mesh theories of Logix gears had been developed. It had been proved that the transmission performance between Logix gears coincides with E-W theorem as that of ordinary standard involute gears. The formula calculating superposition coefficient was deduced according to its definition. Different from standard inv olute gears, the parameter of gear number has no effect on the superposition coe fficient of the Logix gears. Accordingly, bigger ratio transmission can be acqui red by means of decreasing the gear number, and its minimum gear number can be r eached to 3, much smaller than the minimum gear number of ordinary standard invo lute gear: 14~17. This is very important to realize the miniaturization of prod uction design. 5) The CAD special software was developed to design all kinds of Logix gears, an d a solid design example was offered. To sum up, by means of above study, the system info about Logix gear had been de veloped and enriched. This has most significant impact on its widely promotion a nd practical application, on the improvement of carrying capacity, miniaturizati on, and life of kinetic transmission products.
文摘THE pine trees of the Huangshan Mountains surprise many people because of their different artistic and expressive shapes. All through the ages many people have carved poems at the top of the Taishan Mountains. However, my favorite spot is the Heavenly Pond on top of the Changbai Mountains. The Changbai Mountains are located in Antu County in the Yanbian Korean Autonomous Prefecture of Jilin Province.
文摘SOON we’ll celebrate the new year. According to Hangzhou tradition, every family will cook a hot dish for this feast which will include shredded winter bamboo shoots, hotbed chives, shredded meat and smoked bean curd. In addition, some families will also cook a dish of "
文摘EVER since ancient times Shanghai people have pursued beauty. The Shanghai History Museum, mounted an exhibition entitled "Spectacular Garments, Cultural Relics and Documents of Modern Shanghai" which certainly proved this point. This exhibit showed that throughout Shanghai’s long history, dress and personal adomment have been important to the residents. During the
文摘A middle aged woman from Shandong Province showed us her embroidered shirt. The shirt was made of chiffonelle, with embroidered flowers on the front. The shirt was very cool and comfortable, beautiful and dignified, and priced reasonably. These cotton shirts are mostly sold overseas. Shandong Weifang Woolen Clothing Factory is a union of 15 township-owned enterprises in several cities