Residual Concrete Removal from Ready Mixed Concrete Drums

A nozzle housing assembly for a concrete drum cleaning system, comprising:

• a. a nozzle housing having a proximal end configured for attachment to an elongated boom and a leading end, the nozzle housing having an outer surface;
• b. a discharge slot formed through the nozzle housing proximate the leading end;
• c. a high-pressure nozzle rotatably mounted within the nozzle housing, the high-pressure nozzle including a discharge aperture;
• d. a motor operably coupled to the high-pressure nozzle and configured to oscillate the high-pressure nozzle through an angular stroke range;
• and
• e. a fluid conduit interface configured to receive high-pressure water from a source of high-pressure water and to deliver the high-pressure water to the high-pressure nozzle;
• wherein a standoff distance between the discharge aperture and the outer surface of the nozzle housing proximate the leading end is less than about 1 inch;
• and wherein the discharge slot has a length and shape sufficient to align with the discharge aperture throughout the angular stroke range.

A system for removing residual concrete from an interior of a rotatably mounted ready mixed concrete truck drum, comprising:

• a. an elongated boom configured to be inserted into the drum;
• b. a nozzle housing coupled to a leading end of the elongated boom;
• c. a nozzle carried by the nozzle housing and configured to discharge a high-pressure water jet;
• d. a hinge assembly coupling the nozzle housing to the elongated boom to permit pivoting of the nozzle housing relative to the elongated boom about a pivot axis;
• e. a breakaway mechanism associated with the hinge assembly and configured to separate the nozzle housing from the elongated boom when a force or torque between the nozzle housing and the elongated boom reaches a predetermined breakaway threshold;
• and
• f. a source of high-pressure water fluidically coupled to the nozzle;
• wherein the predetermined breakaway threshold is less than a force or torque that would plastically deform the elongated boom.

A breakaway hinge assembly for coupling a nozzle housing to an elongated boom of a concrete drum cleaning system, comprising:

• a. a boom-side hinge body having a plurality of fastener apertures configured to receive fasteners for securing the boom-side hinge body to the elongated boom;
• b. a plurality of pin mounts carried by the boom-side hinge body, the plurality of pin mounts configured to receive a pivot pin that also passes through corresponding pin mounts of the nozzle housing to define a pivot axis about which the nozzle housing pivots relative to the elongated boom;
• c. an actuator mount configured to receive a pin for coupling the breakaway hinge assembly to a hydraulic actuator that pivots the nozzle housing about the pivot axis;
• and
• d. a breakaway structure configured to fail when a force or torque transmitted through the breakaway hinge assembly reaches a predetermined breakaway threshold, thereby enabling separation of the nozzle housing from the elongated boom;
• wherein the predetermined breakaway threshold is less than a force or torque that would plastically deform the elongated boom.