US Patent 7992685 Optical cable lubricator with reservoir

A cable is installed in a duct by means of blowing (and, optionally, synergetic pushing) and lubricating the cable during field installation. Lubricating the cable is done after the cable exits from the cable blowing equipment and hence takes place in a pressurized airflow passage. Lubricant supplied from an external reservoir drains into a pressurized lubricator space through which the cable moves. Foam-plugs seal the entrance and the exit of the lubricator space. The cable is wetted by the lubricant as it moves through the lubricator space, and excess lubricant is wiped by the foam plug, leaving only a thin film of lubricant on the cable as it moves out of the lubricator. In one embodiment, the lubricator is fitted with a single wiping member in the form of an annular plug of open cell foam material, and the cable passes through laterally opposite sections of the annular plug. The lubricator housing is formed in mating sections, and the internal lubricator is also formed in mating sections. The lubricator is integrated with cable blowing equipment in one embodiment. A bundle of guide tubes is lubricated in another embodiment.