Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
207 words
A telescopic strut jib crane comprising: a crane base, a turntable pivotally mounted to said base, a jib mounted to said turntable so as to be able to elevate or lower about a pivot at the base of the jib, said jib comprising at least three telescopic sections, each section telescoping one within the next adjacent telescopic station said sections comprising an outer section, at least one intermediate section and a base section, telescope means for extending telescopically jib sections from said base section, support pulley means mounted to said turntable to the rear of said jib, tie rope means of fixed length, said rope means passing from an anchorage at the head of said intermediate section to and around first extension pulley means at the base of said outer section to and around second extension pulley means at the head of said outer section to and around said support pulley means to and around third extension pulley means at the head of said intermediate section down said intermediate section and around fourth extension pulley means at the base of said intermediate section and to the head of the adjacent lower section, whereby each said section is supported by said rope means from said support pulley means.
Claim 2
Dependent Claim
207 words
A telescopic strut jib crane comprising: a crane base, a turntable pivotally mounted to said base, a jib mounted to said turntable so as to be able to elevate or lower about a pivot at the base of the jib, said jib comprising at least three telescopic sections, each section telescoping one within the next adjacent telescopic station said sections comprising an outer section, at least one intermediate section and a base section, telescope means for extending telescopically jib sections from said base section, support pulley means mounted to said turntable to the rear of said jib, tie rope means of fixed length, said rope means passing from an anchorage at the head of said intermediate section to and around first extension pulley means at the base of said outer section to and around second extension pulley means at the head of said outer section to and around said support pulley means to and around third extension pulley means at the head of said intermediate section down said intermediate section and around fourth extension pulley means at the base of said intermediate section and to the head of the adjacent lower section, whereby each said section is supported by said rope means from said support pulley means.
Claim 3
Dependent Claim
65 words
A crane as claimed in claim 1 wherein the tie rope means has first and second ends, said first end at said anchorage at the head of said intermediate section and said second end at the foot of the intermediate section immediately adjacent the base section, the tie rope means then extending to a fifth extension pulley means at the head of the base section.
Claim 4
Dependent Claim
30 words
A crane as claimed in claim 2 wherein there are three telescopic sections, the tie rope means extending from the fifth extension pulley means to the fourth extension pulley means.
Claim 5
Dependent Claim
27 words
A crane as claimed in claim 1 wherein said tie rope means comprises two tie ropes, one said rope being provided on each side of said jib.
Claim 6
Dependent Claim
34 words
A crane as claimed in claim 1 wherein the support pulley means is provided at the head of a derrick mast, the lower end of the mast being pivotally mounted to the crane turntable.
Claim 7
Dependent Claim
26 words
A crane as claimed in claim 5 wherein the derrick mast is raised or lowered by a hydraulic ram acting between the mast and the turntable.
Claim 8
Dependent Claim
19 words
A crane as claimed in claim 1 wherein said crane base comprises the chassis of a mobile crane vehicle.