Suspension connectors for mast-supported street lights are well known in the prior art. Such connectors allow the bulbs of the street light to be changed without the need for a cherry-picker truck to lift a man to the top of the support mast. Such connectors generally comprise a female, spring clip electrical connector mounted within a bell-shaped housing which in turn is secured onto the arm of the support mast. The street lights are screwed into a fixture having a prong-type male electrical connector. The light fixture and male connector may be lifted and lowered with respect to the female connector by means of a cable connected to a hand-cranked winch located at the base of the mast. A latching mechanism is provided between the male and female connectors for latching and unlatching them whenever the male connector is forcefully engaged against the female connector for a predetermined distance (referred to hereinafter as the latching stroke distance).
When it becomes necessary to change a burned-out bulb or to perform some other maintenance operation on the light fixture, the system operator first obtains access to the winch (which is usually stored within a hollow section of the mast). The winch is then cranked so that the cable forcefully engages the male connector against the female connector. Such an action unlatches the cam-operated latching mechanism. The operator then unwinds the reel of the winch. The weight of the light fixture and male connector is greater than the frictional force between the prongs of the male connector and the blade-type receivers of the female connector. Consequently, the male connector and light fixture will disengage from the female connector. The operator can then gently lower the male connector and light fixture by unreeling the cable of the winch. After the light fixture has been lowered to a convenient height, the bulb replacement or other maintenance operation is performed. The light fixture and male connector are then raised via the cable of the hoisting mechanism both to reengage the male and female connectors and to relatch the latching mechanism.
Broadly speaking, the invention is an improved suspension connector assembly capable of reliably interconnecting a plurality of connector pins and barrels without the shortcomings associated with the prior art. The suspension connector assembly of the invention includes a female connector mounted within a stationary, bell-shaped housing, a movable male connector adapted to be raised and lowered toward and away from the female connector via a hoisting cable, a latching mechanism for latching and unlatching the male connector to and from the female connector, and a resilient mounting assembly for mounting the female connector within the interior of the housing. The mounting assembly includes one or more coil springs whose resiliency stroke is at least as long as the stroke distance required by the latching mechanism to latch and unlatch the male connector from the female connector. Additionally, the stiffness of the springs used in the mounting assembly is greater than the amount of force needed to completely insert the connector pins into their respective barrels. Hence, when the cable of the hoisting mechanism begins to push the connector pins of the male connector into the connector barrels of the female connector, the pins and barrels will become fully mated before the compression springs of the assembly become fully compressed. Because the resiliency stroke of the springs of the mounting assembly is greater than the stroke necessary for the latching mechanism to operate, the pins will not become partially withdrawn from their respective barrels at the completion of the latching stroke.
In the preferred embodiment, the resilient mounting assembly includes a pair of guide rods connected to a support plate which is mounted within the bell-shaped housing. The guide rods are slidably movable within guide sleeves disposed within bores present in the female connector. The aforementioned compression springs are concentrically disposed around the guide rods, and are compressed on one end by a top edge of a guide sleeve, and on the other end by the base plate. The resilient mounting assembly may further include a pair of retaining screws which not only retain the female connector to the base plate, but further define the stroke of the mounting assembly. In the preferred embodiment, the ends of the retaining screws are mounted on the base plate, while the heads are disposed within (and slidably movable within) bores present in the female connector. Retaining sleeves concentrically disposed at the top ends of the retaining bores prevent the heads of the retaining screws from being pulled out of the bores, thereby retaining the female connector to the support plate.
While this invention has been described with respect to a particular preferred embodiment, various modifications, variations, and additions will become apparent to persons skilled in the art. All such additions, modifications, and variations are intended to be encompassed within the scope of this patent, which is limited only by the claims appended hereto.
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