Boom extension and contraction mechanism for crane apparatus
A boom extension and contraction mechanism for a crane apparatus includes: a flow passage switching mechanism that switches a flow passage of the hydraulic oil between the cylinder-to-boom connection switching cylinder side and the boom member connection switching cylinder side; a hose reel configured to reel out a hydraulic hose as a telescopic cylinder is extending, and to reel off the hydraulic hose as the telescopic cylinder is contracting; a cable used to supply power and transmit a signal between a swivel base and a boom; and a cord reel configured to reel out the cable as the telescopic cylinder is extending and to reel off the cable as the telescopic cylinder is contracting. The code reel and the hose reel are arranged on the base in a direction in which the boom extends and contracts.
1. A boom extension and contraction mechanism for a crane apparatus comprising:
a boom including a plurality of boom members, the boom extending and contracting by shifting next boom members in front of respective ones with respect to the boom members other than a top boom member;
a base configured to support a base end of a bottom boom member;
a telescopic cylinder including a cylinder rod and a cylinder tube, one of the cylinder rod and the cylinder tube being connected to the bottom boom member to extend and contract the boom;
a cylinder-to-boom connection mechanism configured to be able to connect and disconnect between the other of the cylinder rod and the cylinder tube and the boom members other than the bottom boom member;
a boom member connection mechanism configured to be able to connect between the boom members next to one another and release the boom members from being connected to one another;
a cylinder-to-boom connection switching cylinder configured to allow the cylinder-to-boom connection mechanism to perform one of a connecting operation and a disconnecting operation between the telescopic cylinder and a boom member by supplying hydraulic oil, and to allow the cylinder-to-boom connection mechanism to perform the other of the connecting operation and the disconnecting operation between the telescopic cylinder and the boom member by stopping supplying the hydraulic oil;
a boom member connection switching cylinder configured to allow the boom member connection mechanism to perform one of a connecting operation and a disconnecting operation between the boom members next to one another by supplying the hydraulic oil, and to allow the boom member connection mechanism to perform the other of the connecting operation and the disconnecting operation between the boom members next to one another by stopping supplying the hydraulic oil;
only one hydraulic hose configured to supply the hydraulic oil from the base side to the cylinder-to-boom connection switching cylinder and the boom member connection switching cylinder;
a flow passage switching mechanism configured to switch a flow passage of the hydraulic oil supplied via the hydraulic hose between the cylinder-to-boom connection switching cylinder side and the boom member connection switching cylinder side;
a hose reel configured to reel out the hydraulic hose as the telescopic cylinder is extending, and to reel off the hydraulic hose as the telescopic cylinder is contracting, the hose reel having a dimension in a direction of a rotating axis that allows the hydraulic hose to be wound around the hose reel in the direction of the rotating axis;
a cable used to supply power from the base side to equipment provided in the other of the cylinder rod and the cylinder tube of the telescopic cylinder, and to transmit a signal from the equipment to the base side; and
a cord reel configured to reel out the cable as the telescopic cylinder is extending and to reel off the cable as the telescopic cylinder is contracting, the cord reel having a dimension in the direction of the rotating axis that allows the cable to be wound around the cord reel in the direction of the rotating axis,
wherein the hose reel and the cord reel are arranged on the base in a direction in which the boom extends and contracts.