Model sxb 430 book sewing machine adopts stepless change device , central lubricating system , parallel control spring for sewing frame and has safety guards on all moving parts 该机采用无级调速装置,集中润滑系统和订书架的平衡控制,运动部位均设有安全防护罩,故机器运装平稳,噪音低。
control springとは意味:コントロール?スプリング、制御{せいぎょ}バネ control spring meaning:[Design engineering] "A spring designed so that its torque cancels that of the instrument of which it is a part, for all deflections of the pointer."control spring перевод:= controlling spring устанавливающая пружина, регулирующая пружина