US 4,570,348 A · Measuring apparatus

Abstract

Apparatus for measuring length of an elongate cable. A frame having a hole therethrough includes a pair of rollers mounted for rotation thereon. The circumferences of the rollers are rollingly engaged with one another over the hole and a cable which is to be measured is held between the rollers and passed downwardly through the hole thereby rotating the rollers. A magnet is mounted on one of the rollers adjacent the circumference thereof. Mounted on the frame adjacent the circumference of the roller having the magnet mounted thereon is a magnetically-activated switch which closes each time the magnet passes thereby. The switch provides an input to a transmitter which generates a signal including pulses indicative of the number of rotations of the wheel having the magnet mounted thereon. The signal is received by a receiver and the pulses are counted and displayed in order to provide a visual indication of the number of pulses, such being directly proportional to the length of cable which passes between the rollers.

Claims13

Dependent claims

A measuring apparatus comprising:

a substantially planar frame;
a first axle support mounted on the upper side of said frame;
a first axle mounted on said first axle support;
a first roller rotatably mounted on said first axle;
a second axle support mounted on the upper side of said frame;
a second axle mounted on said second axle support;
a second roller rotatably mounted on said second axle, said first and second axles being substantially parallel and the edges of said rollers being opposite one another;
a tubular base extending downwardly from the lower side of said frame with the axis of said base being at a substantially right angle to said frame;
an opening in said frame to permit communication between the interior of said base and the upper side of said frame;
a first slot formed in said frame and extending from one edge thereof to said opening;
a second slot formed axially in said tubular base along the length thereof, said first and second slots being in alignment with one another;
a magnet mounted on one of said rollers adjacent the circumference thereof;
and
means for detecting a magnetic field mounted on said frame adjacent the circumference of the roller having said magnet mounted thereon.

11 more elements

Apparatus for providing a measurement of the amount of cable lowered into a well bore having a cylindrical tube extending from the top thereof, said apparatus comprising:

a substantially planar platform;
a tubular base extending downwardly from the lower side of said platform with the axis of said base being at a substantially right angle to said platform, said base having a diameter which permits sliding coaxial engagement with said cylindrical tube;
a bore formed in said platform to permit communication between the interior of said base and the top of said platform;
a first slot formed in said platform and extending from one edge thereof to said bore;
a second slot formed axially in said tubular base along the length thereof, said first and second slots being in alignment with one another;
a roller mounted for rotation on top of said platform adjacent said bore;
means for engaging such a cable which extends through said bore with said roller so that for a given length of cable passed through said bore, said roller rotates through a predetermined arc;
a magnet mounted on said roller adjacent the circumference thereof;
and
means for detecting a magnetic field mounted on said platform adjacent the circumference of said rollers.

7 more elements

Dependencies are inferred from the claim text.

Measuring apparatus

Life of this patent

Measuring apparatus

Life of this patent

Abstract

Claims13