Abstract:
A safety braking device configured for use with the counterbalancing system of a garage door. The safety braking device includes a support bracket, a ratchet wheel, a pawl arm, and a biasing spring. The support bracket is rigidly connected to a fixed structure and has a guiding slot. The ratchet wheel is securely mounted about the overhead shaft of the counterbalancing system and has at least one notch. The pawl arm has first and second ends, the first end of the pawl arm being pivotally connected to the support bracket and the second end of the pawl arm cooperating with the guiding slot and being movable with respect to the support bracket along said guiding slot. The first and second ends of the pawl arm are further connected to flanges of a plug on either side of the overhead shaft. The biasing spring is operatively connected between the support bracket and the pawl arm so as to exert a biasing force for biasing the pawl arm towards the ratchet wheel. The pawl arm is devised so that, an element thereof is adjacent to the ratchet wheel, said element being shaped and sized to be removably insertable into at least one notch of the ratchet wheel so as to block rotation of the ratchet wheel, and thus block rotation of the overhead shaft, in the event of a failure of the counterbalancing system of the door.
Abstract:
A hydraulic governor device for use with a rotational shaft of a door assembly for controlling a rotation of said rotational shaft. The device includes a sleeve; first and second end coverings mounted respectively onto first and second ends of the sleeve so as to define an hydraulic flow path; a fluid substantially filling the hydraulic flow path; an input shaft extending through the ends coverings and the chamber, and being operatively connected to the rotational shaft of the door assembly; first and second pistons disks positioned inside the chamber and mounted about the input shaft, the pistons disks being connected to each other and being slidably movable along the input shaft; and a reciprocating assembly operatively connected between the input shaft and the piston disks and cooperating with the same for converting a rotation of the input shaft into a reciprocating movement of the pistons disks within a chamber, so that said reciprocating movement of the pistons disks inside the chamber causes in turn the fluid to travel along a reciprocating movement along the hydraulic flow path, said reciprocating movement of the fluid along the hydraulic flow path causing a damping effect of the rotation of the input shaft and thus controlling the rotation of the rotational shaft of the door assembly via a damping effect.