Cable feeding apparatus
AssigneeArnco Corporation
InventorsGerald A. Kaminski, Dennis B. Laska, Joseph V. Negowski, Robert C. Brod
Life of this patent
Estimating the term…
Abstract
An improved cable feeder uses tractor type drive belts and compressed air to propel cable through a conduit. The axial force applied to the cable is sensed with a strain gauge near the conduit or a pressure detector in a hydraulic system powering the drive belts. If excessive force is applied, hydraulic fluid is diverted from the drive belts. The radial force applied to the cable is limited by a calibrated spring. The feeder can also be arranged in a mid-assist configuration. Conduits and the cable are sealed to maintain air pressure. A by-pass pipe is provided to convey pressurized air from a first conduit to a succeeding conduit.
Claims27
An apparatus for installing cable in a tubular conduit, comprising:
- a driver adapted to engage the cable for applying an axial compressive force on the cable to propel the cable forwardly into the conduit;
- and
- a sensor operatively connected to the conduit downstream of the driver for constantly measuring axial force applied to the conduit by the cable moving therethrough to indicate axial compressive loads applied to the cable by the driver, the sensor measuring the axial force on the conduit while the cable is propelled in an axial direction regardless of the deflection of the cable at the point of measurement, the sensor being connected to control the driver in response to a sensed force whereby limits of axial compressive loads on the cable may be set to protect the cable from excessive axial compressive loads before the cable is damaged but while it is still moving in an axial direction.
An apparatus for installing cable in a tubular conduit, comprising:
- a driver including a pair of opposed rotating members adapted to engage the cable for applying an axial compressive force on the cable to propel the cable into the conduit;
- a fitting adapted to be connected to a compressed air source, said fitting adapted to direct the air into the conduit to trap the air behind a dart connected to a leading end of the cable so as to create a tensile force on the cable to propel the cable through the conduit;
- a sensor operatively connected to the conduit downstream of the rotating members for constantly measuring axial force applied to the conduit by the cable moving therethrough to indicate axial compressive loads on the cable, the sensor measuring the axial force on the conduit while the cable is moving in an axial direction regardless of the deflection of the cable at the point of measurement, the axial compressive loads on the cable being applied primarily by the rotating members;
- a hydraulic system for powering the rotating members;
- and
- a control system connected to divert hydraulic fluid from the rotating members in response to a sensed axial force exceeding a specified limit whereby limits of axial compressive loads on the cable may be set to protect the cable from excessive axial compressive loads before the cable is damaged but while it is still moving in an axial direction.
An apparatus for installing fiber optic cable in a tubular conduit, comprising:
- a driver adapted to engage the cable for applying an axial compressive force on the cable to propel the cable forwardly into the conduit;
- a sensor operatively connected to the conduit for measuring axial force applied to the conduit by the cable moving therethrough to indicate axial compressive loads applied to the cable by the driver and connected to control the driver in response to a sensed force;
- and
- the sensor including a strain gauge rigidly mounted relative to and closely downstream from the driver, the conduit being rigidly mounted in a duct clamp, the clamp being moveably mounted relative to the driver and operably in contact with the strain gauge so that the strain gauge measures the axial force tending to move the conduit which is a measure of the axial compressive loads on the cable.
Dependencies are inferred from the claim text.