Unit tray hold down mechanism

摘要

The hold down apparatus securely engages a unit onto a tray. The tray includes an opening having a front block on the underside of the tray at the opening. The front block also includes a pin. The apparatus comprises a housing having an internal space and is placed in the unit such that the housing space is opened to an opening in the bottom of the unit. A control shaft extends from outside the apparatus and into the housing space to the backplate of the housing. The portion of the control shaft in the housing space is threaded. The external portion of the control shaft is accessible from the front of the unit. An L-shaped pawl has a foot and a rise, the foot of the pawl having a notch in the front edge of the foot. The pawl also has a threaded hole in the rise along an axis parallel to the foot such that when the control shaft is turned the foot of the pawl extends into the opening of the tray from an initial recessed position in the housing space, and is then moved forward causing the notch of the foot to engage the pin of the tray thereby securely holding the unit to the tray.