SPRING-ASSISTED MECHANISM FOR RAISING AND LOWERING A LOAD

摘要

An apparatus for selectively raising, lowering or otherwise moving load such or panel, or other article such as a pet door comprises a frame, a panel, a motor, a constant tension spring, and a control system. The panel is carried by the frame for movement between an open position and a closed position. The spring is attached to the panel to bias the panel open. The frame includes a plurality of groves retaining seals such as fibrous weatherscal to sea] the interface between the panel and the frame against penetration by the elements. The control system is in communication with the motor to actuate the motor, thereby moving the panel with the assistance of the spring. The control system includes an antenna in the panel for emitting a low frequency (RFID) signal, and a fob that is worn by a pet to communicate with the antenna to actuate the motor.