Method for raising strut, and crane

Patent metadata

Field	Value
Publication number	US-10633227-B2
Application number	US-201815995362-A
Country	US
Kind code	B2
Filing date	Jun 1, 2018
Priority date	Jun 5, 2017
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

Disclosed is a technique of executing: a fixing step of coupling a pulling-raising rope 171 to a vicinity of a distal end 73 of a strut 70; a first raising step of pulling the pulling-raising rope 171 rearwardly to cause a swingable portion 78 of the strut 70 to swing upwardly and rearwardly; a second raising step of pulling the pulling-raising rope 171 rearwardly until a strut body portion 76 has a rearwardly inclined posture with respect to a vertical direction; a strut returning step of pulling a pulling-returning rope 23a forwardly to a position where a forward swinging movement of the swingable portion 78 with respect to the strut body portion 76 is restricted; and a coupling step of coupling the swingable portion 78 and the strut body portion 76 to each other in a non-swingable manner.

First claim

The invention claimed is:

1. A strut raising method used for a crane comprising: a crane base; a boom attached to the crane base in a raisable and lowerable manner; a jib attached to the boom in a raisable and lowerable manner; and a strut for supporting the jib, the strut having a base end attached to the boom in a raisable and lowerable manner and a distal end located on a side opposite to the base end, the strut raising method comprising:
configuring the strut such that it comprises: a strut body portion including the base end; a swingable portion including the distal end, the swingable portion being located closer to a distal edge of the strut than the strut body portion and swingably coupled to the strut body portion; and a restriction portion for restricting a swinging movement of the swingable portion with respect to the strut body portion;
fixing a pulling-raising rope to a vicinity of the distal end of the strut, in a state in which the strut is located forward of the boom in terms of a forward-rearward direction of the boom, wherein the boom and the strut are laid down along an installation surface of the crane, and wherein the strut body portion is disposed to extend forwardly from the boom, and the swingable portion is disposed to extend forwardly from the strut body portion;
performing a first raising operation of pulling the pulling-raising rope rearwardly to cause the swingable portion to swing upwardly and rearwardly with respect to the strut body portion after the fixing of the pulling-raising rope, up to a position where a rearward swinging movement of the swingable portion with respect to the strut body portion is restricted by the restriction portion;
performing a second raising operation of pulling the pulling-raising rope rearwardly until the strut body portion has a rearwardly inclined posture with respect to a vertical direction after the first raising operation, to cause the strut body portion to swing upwardly and rearwardly with respect to the boom;
pulling a pulling-returning rope coupled to the distal end of the strut forwardly to cause the swingable portion to swing forwardly with respect to the strut body portion after the second raising operation to thereby return the strut to a position where the strut body portion comes into contact with the swingable portion to thereby restrict the swingable portion from a relative forward swinging movement to the strut body portion; and
coupling the swingable portion and the strut body portion to each other so as to prevent the swingable portion and the strut body portion from relative swinging movement to each other after returning the strut to the position where the strut body portion comes into contact with the swingable portion.

2. A crane comprising:
a crane base;
a boom attached to the crane base in a raisable and lowerable manner;
a jib attached to the boom in a raisable and lowerable manner; and
a strut for supporting the jib, the strut having a base end attached to the boom in a raisable and lowerable manner and a distal end located on a side opposite to the base end,
wherein the strut comprises:
a strut body portion located on the side of the base end;
a swingable portion located on the side of the distal end and swingably coupled to the strut body portion;
a restriction portion for restricting the swingable portion from a relative swinging movement to the strut body portion in a direction causing the angle to be increased beyond the given value, when an angle between the strut body portion and the swingable portion becomes a given value; and
a swinging movement-restricting coupling portion capable of coupling the strut body portion and the swingable portion to each other so as to prevent the strut body portion and the swingable portion from a relative swinging movement to each other,

and wherein the strut has, in a vicinity of the distal end thereof, a first holding portion for allowing a pulling-raising rope for pulling the swingable portion toward the boom to be fixed thereto, and a second holding portion for allowing a pulling-returning rope for pulling the swingable portion in a direction away from the boom to be coupled thereto.

Assignees

• Kobelco Constr Mach Co Ltd

Inventors

• Brueckner Detlef

Classifications

• B66C23/68

  foldable or otherwise adjustable in configuration · CPC title

• B66C23/346 Primary

  with locking devices · CPC title

• B66C23/42

  with jibs of adjustable configuration, e.g. foldable · CPC title

• B66C23/82 Primary

  Luffing gear · CPC title