A new-type bike features that its pedal crank has an arc rack bar acting on the ratchet gear in single direction and in turn driving the drive chain wheel, a reset unit composed of crank mechanism is used to make left and right pedal cranks be pedaled alternatively, and its front movable saddle plate is connected via connecting rod to pedal crank for making rider comfortable. Its advantages are high drive performance and efficiency and saving labour.

一種新式自行車com超碰在，其最大特點(diǎn)是蹬踏桿上含有一弧形齒條欧美性爱视频在线观看鲁片，由該弧形齒條上的輪齒作用于具有單向離合的棘齒輪色人人国产，從而帶動(dòng)主動(dòng)鏈輪轉(zhuǎn)動(dòng)亚洲免费aa视频，由曲柄機(jī)構(gòu)組成的復(fù)位器使左右蹬踏桿能夠交替連續(xù)踩踏以驅(qū)動(dòng)自行車行駛，前活動(dòng)座板與蹬踏桿由連桿相連結(jié)日韩妓女精品影院视频播放，從而實(shí)現(xiàn)同步擺動(dòng)給以乘騎者踩踏感到舒適国产一级特黄特色多人视频，該發(fā)明具有傳動(dòng)性能好，效率高欧美日产国产变态精品，力損耗小等優(yōu)點(diǎn)日韩性爱黄片。

crank brace with ratchet：帶有棘爪手搖鉆

crank bearing 曲軸軸承 | crank brace with ratchet 帶有棘爪手搖鉆 | crank brass 曲柄銷軸承銅襯

starting crank ratchet：起動(dòng)曲柄棘輪機(jī)構(gòu)

starting crank pin ==> 起動(dòng)曲柄銷 | starting crank ratchet ==> 起動(dòng)曲柄棘輪機(jī)構(gòu) | starting crank shaft ==> 起動(dòng)曲柄軸