Through ratchet mechanism

The disclosed adjustable strap device may include a left strap having a first rack member and a right strap having a second rack member. The electrical unit may have an opening through which the shaft passes. The pinion member may be attached to a proximal end of the shaft and may be adapted to (a) engage the first and second rack members, and (b) translate the first and second rack members in opposite directions via rotation of the shaft. The ratchet member may be coupled to a distal end of the shaft and may include one or more pawls adapted to prevent rotation of the shaft when engaged. Various other methods, systems, and devices are also disclosed. 所公开的可调节带装置可包括具有第一齿条构件的左带和具有第二齿条构件的右带。电气单元可以具有开口，轴贯通该开口。小齿轮构件可以附接到轴的近端，并且可以适于(a)啮合第一齿条构件和第二齿条构件，以及(b)经由轴的旋转使第一齿条构件和第二齿条构件在相反的方向上平移。棘轮构件可以耦合到轴的远端，并且可以包括适于在啮合时防止轴的旋转的一个或更多个棘爪。还公开了多种其他方法、系统和设备。