Side stowable jib for crane booms and jib mounting

Claim 2

In a crane, an extensible boom having a base section and a fly section, a jib attachable to the nose of the fly section in a forwardly extending use position, and means to support the jib in a stowed position along one side of the boom base section and to facilitate coupling the jib to said nose in said use position, said means including spaced front and rear bracket assemblies on one side of the boom base section to support the jib bodily with the base end of the jib disposed forwardly in the stowed position in spaced relation to said nose of the fly section, means forming a first pivotal connection between the jib and front bracket assembly and allowing swinging of the base end of the jib on a radius around said means forming said first pivotal connection from the stowed position where it is spaced outwardly from the nose laterally inwardly into an aligned coupling position with said nose, said first pivotal connection including a releasable securing means for the jib on the front bracket assembly, separable means forming a second pivotal connection between the base end of the jib and said nose in the aligned coupling position and allowing further swinging of the jib on the axis of the second pivotal connection to said use position upon release of said releasable securing means, and separable coupling means locking the jib in said use position rigidly.

Claim 3

The structure of claim 1, and the base end of said jib including two laterally spaced pairs of apertured coupling elements with the coupling elements in each pair vertically spaced and having their apertures in vertical alignment in the pairs, said separable means forming a second pivotal connection comprising a pair of axially aligned pivot pins engageable through the apertures of one vertically aligned pair of said elements and through registering apertures in parts of said nose.

Claim 4

The structure of claim 2, and said nose including a pair of vertically spaced horizontal shafts whose opposite ends are slotted to receive said pairs of coupling elements and apertured to register with the apertures in said coupling elements when the latter are in the slots of said shafts.

Claim 5

The structure of claim 3, and said separable coupling means locking said jib comprising another pair of vertically aligned pins engaging through the other pair of coupling elements on the base end of the jib and through the other slotted apertured ends of said shafts.

Claim 6

The structure of claim 1, and said front bracket assembly being bodily adjustable on the boom base section in at least two directions, said Rear bracket assembly including a jib support member which is bodily adjustable in at least one direction relative to said base section.

Claim 7

The structure of claim 1, and said front bracket assembly comprising a mounting member secured to one side wall of the boom base section, a vertical axis pivot element on the mounting member, a jib retainer unit having a pivotal connection with the vertical axis pivot element and having upper and lower side opening sockets for a pair of corner bars of the jib, and a pair of removable retainer pins engaging across the open sides of said sockets to lock the jib corner bars therein.

Claim 8

The structure of claim 6, and lockable screw-threaded means to adjust the mounting member upwardly and downwardly on the side wall of the boom base section, and a separate lockable screw-threaded means to adjust the upper socket and the upper end of said pivot element inwardly and outwardly relative to the side wall of the boom base section.

Claim 9

The structure of claim 6, and each socket comprising a pair of spaced apertured plates projecting outwardly of said pivot element, and said removable retainer pins engageable through the apertures of said socket forming pairs of plates.

Claim 10

The structure of claim 1, and said rear bracket assembly comprising substantially horizontal support member rigid with one side of the boom base section and projecting laterally thereof, a vertically adjustable and lockable track member on said horizontal support member including an inclined ramp element at the outer end of the track member, a socket and abutment element on the track member near its inner end adapted to receive a guide roller means on the inner lower corner bar of the jib, and a three position pivoted latch plate on the track member near the outer end thereof, and means to releasably lock the latch plate rigidly in a jib locking position and in an intermediate safety position, the third position of the latch plate being a free-hanging position where the latch plate is clear of the top of the track member and said ramp element.

Claim 11

The structure of claim 9, and said latch plate having a finger extension which overlies the outer lower corner bar of the jib in said jib locking position, said finger extension being vertically disposed in the path of horizontal swinging movement of the outer lower jib corner bar when the latch plate is locked in said intermediate safety position.

Claim 12

The structure of claim 1, and interengaging rigid means on the telescoping sections of the extensible boom to prevent axial twisting of the boom sections caused by the weight of the jib when the latter is extending transversely of the boom during its pivotal movement from its side stowed position to its forwardly extending use position.

Claim 13

The structure of claim 1, and said means forming a first pivotal connection being on the boom base section and being formed by a stationary unit of the front bracket assembly attached to the base section and a movable unit of the front bracket assembly attachable to the jib.

Claim 14

The structure of claim 1, and said means forming a first pivotal connection comprising a pivot element on the jib connected with a part of the front bracket assembly and spaced laterally outwardly of the boom base section.

Claim 15

A boom jib mounting comprising in combination a crane boom having a nose element, a jib for the crane boom attachable to the nose element in a forwardly extending use position and being stowable at one side of the boom with the base end of the jib projecting forwardly and laterally outwardly spaced from the nose element in the stowed position, a front support bracket assembly for the jib on said one side of the boom including a jib holding unit which is pivotal on a substantially vertical axis and which includes releasable jib retaining means, a rear jib supporting bracket assembly on said one side of the boom spaced substantially rearwardly of the front bracket assembly and including a multi-position jib latch which in one position locks the jib rigidly to the rear bracket assembly and in another position releases the jib so that it can move clear of the rear bracket assembly, the latch when in an intermediate safety position allowing restricted movement of the jib on the rear bracket assembly when the jib is pivoting with the jib holding unit of the front bracket assembly, means to pivotally interconnect the base end of the jib with said nose element when the jib base end pivots with said jib holding unit laterally inwardly along a radius about said substantially vertical axis bringing the base end of the jib into a registered interconnecting position with said nose element and when said latch is in the intermediate position, and means to rigidly couple the base end of the jib to the nose element after the jib has been further swung substantially 180 degrees on the pivot axis of the connection between the jib and nose element and after the latch has been moved to the jib release position and after release of said jib retaining means on the pivotal jib holding unit of the front bracket assembly.

Claim 16

A boom jib mounting comprising in combination a crane boom having a nose element, a jib for the crane boom attachable to the nose element in a forwardly extending use position and being stowable at one side of the boom with the base end of the jib projecting forwardly and laterally outwardly spaced from the nose element in the stowed position, a front support bracket assembly for the jib on said one side of the boom including a jib holding unit which is pivotal on a substantially vertical axis and which includes releasable jib retaining means, a rear jib supporting bracket assembly on said one side of the boom spaced substantially rearwardly of the front bracket assembly and including a multi-position jib latch which in one position locks the jib rigidly to the rear bracket assembly and in another position releases the jib so that it can move clear of the rear bracket assembly, the latch when in an intermediate safety position allowing restricted movement of the jib on the rear bracket assembly when the jib is pivoting with the jib holding unit of the front bracket assembly, means to pivotally interconnect the base end of the jib with said nose element when the jib base end pivots with said jib holding unit laterally inwardly along a radius about said substantially vertical axis bringing the base end of the jib into a registered interconnecting position with said nose element and when said latch is in the intermediate position, and means to rigidly couple the base end of the jib to the nose element after the jib has been further swung substantially 180 degrees on the pivot axis of the connection between the jib and nose element and after the latch has been moved to the jib release position and after release of said jib retaining means on the pivotal jib holding unit of the front bracket assembly.

Claim 17

The structure of claim 14, and said jib retaining means comprising removable locking pin means on said pivotal jib holding unit.

Claim 18

The structure of claim 14, and said means to pivotally interconnect the base end of the jib with said nose element and the means to rigidly couple the base end to the nose element both comprising removable pin means.

Claim 19

A boom jib mounting comprising in combination a crane boom having a nose assembly, a jib having a base end attachable to the nose assembly in a forwardly extending use position, means pivotally connecting said jib to one side of the boom base section for mounting said jib in a stowed position along one side of the boom base section whereby the base end of said jib is spaced laterally outwardly from said nose assembly and is pivotal from the stowed position laterally inwardly into registration with said nose assembly along a radius around said pivotal connection means, second means forming a second pivotal connection between the base end of said jib and said nose assembly on the same side of said boom as said first pivotal connection means and allowing further pivotal swinging of said jib about said second means to said forwardly extending use position upon release of said first pivotal connection means.

Claim 20

A boom jib mounting comprising in combination a crane boom having a nose assembly, a jib having a base end attachable to the nose assembly in a forwardly extending use position, means pivotally connecting said jib to one side of the boom base section for mounting said jib in a stowed position along one side of the boom base section whereby the base end of said jib is spaced laterally outwardly from said nose assembly and is pivotal from the stowed position laterally inwardly into registration with said nose assembly along a radius around said pivotal connection means, second means forming a second pivotal connection between the base end of said jib and said nose assembly on the same side of said boom as said first pivotal connection means and allowing further pivotal swinging of said jib about said second means to said forwardly extending use position upon release of said first pivotal connection means.