Mobile crane with jib extension

Claim 2

Crane structure comprising: a base; a main boom pivotally mounted on said base, said main boom including an inner boom section of rectangular construction and at least one extension section mounted for telescopic movement relative to said inner section; a jib boom; means mounting said jib boom for movement between a usable position in alignment with said main boom and a storage position located along one of the vertical sides of said inner boom section, said mounting means including attachment means on said jib boom and connection means on said extension section engageable with said attachment means, said connection means being provided on a connection member which is mounted for movement about an upright pivot axis on said extension section that is generally perpendicular to the length of said main boom, means releasably retaining said connection member in a first position for supporting said jib section in said usable position, the pivotal connection between said connection member and extension section allowing said connection member and jib section to swing in a generally horizontal plane between said usable and storage positions upon release of said retaining means, disengagement of said attachment means and connection means allowing said extension section to be extended and retracted when said jib section is in the storage position; and support means at one side of said inner section transversely attached to the bottom wall of said inner boom section and extending laterally outward for positively retaining said jib section in said storage position.

Claim 3

Crane structure as set forth in claim 1 wherein said support means is defined by longitudinally spaced support members positioned beneath said jib section when said jib section is in said storage position.

Claim 4

Crane structure as set forth in claim 1 including stabilizing means connected between said main boom and said jib section for supporting said jib section in said usable position.

Claim 5

Crane struCture as set forth in claim 3 wherein said stabilizing means is defined by at least one elongate member connected at one end adjacent the end of said jib section, and detachably connected at the opposite end to said main boom.

Claim 6

Crane structure as set forth in claim 4 including means on said jib section for supporting said stabilizing member when said section is in said storage position.

Claim 7

Crane structure as set forth in claim 1 wherein said jib section includes a main portion and a further portion telescopically positioned therein.

Claim 8

Crane structure comprising: a base; a main boom pivotally mounted on said base, said main boom including an inner boom section having a bottom and sides and at least one extension section mounted for telescopic movement relative to said inner section; a further extension section; means mounting said further extension section for movement between a usable position in alignment with said main boom and a storage position located along one side of said inner boom section, said mounting means including attachment means on said further extension section and connection means on said extension section cooperable with said attachment means, said attachment means and connection means defining an upright pivot axis adjacent one side of the outer end of said extension section, said pivot axis being generally perpendicular to the length of said main boom; means releasably retaining said further extension section in said usable position, said pivot axis allowing said further extension section to swing in a generally horizontal plane between said usable and storage positions upon release of said retaining means, disengagement of said attachment means and connection means allowing said extension section to be extended and retracted when said further extension section is in the storage position; first and second longitudinally spaced support members extending generally transversely outwardly from said one side of said inner section adjacent the lower portion thereof, said support members each defining an upper support surface and said support surfaces collectively defining an upwardly facing shelf upon which said further extension section rests in said storage position; and cooperating means on said inner section and said further extension section means for releasably retaining said further extension section in said storage position on the upwardly facing shelf defined by said support surfaces, the cooperating means on said inner section and said further extension section being positioned in operative association when said further extension section is in the storage position, whereby said cooperating means can be engaged independently of telescopic movement of the extension section of the main boom.

Claim 9

Crane structure comprising: a base; a main boom pivotally mounted on said base, said main boom including an inner boom section having a bottom and sides and at least one extension section mounted for telescopic movement relative to said inner section; a further extension section; means mounting said further extension section for movement between a usable position in alignment with said main boom and a storage position located along one side of said inner boom section, said mounting means including attachment means on said further extension section and connection means on said extension section cooperable with said attachment means, said attachment means and connection means defining an upright pivot axis adjacent one side of the outer end of said extension section, said pivot axis being generally perpendicular to the length of said main boom; means releasably retaining said further extension section in said usable position, said pivot axis allowing said further extension section to swing in a generally horizontal plane between said usable and storage positions upon release of said retaining means, disengagement of said attachment means and connection means allowing said extension section to be extended and retracted when said further extension section is in the storage position; first and second longitudinally spaced support members extending generally transversely outwardly from said one side of said inner section adjacent the lower portion thereof, said support members each defining an upper support surface and said support surfaces collectively defining an upwardly facing shelf upon which said further extension section rests in said storage position; and cooperating means on said inner section and said further extension section means for releasably retaining said further extension section in said storage position on the upwardly facing shelf defined by said support surfaces, the cooperating means on said inner section and said further extension section being positioned in operative association when said further extension section is in the storage position, whereby said cooperating means can be engaged independently of telescopic movement of the extension section of the main boom.

Claim 10

Crane structure as set forth in claim 7 wherein said support means includes longitudinally spaced support members on said inner section positioned to engage said further extension section at positions spaced a substantial distance outwardly of the mid-portion of said further extension section.

Claim 11

Crane structure as set forth in claim 7 wherein said support means and said cooperating means retain said further extension section in spaced parallel relationship with said inner section in said storage position.

Claim 12

Crane structure as set forth in claim 7 in which said connection means includes a female element at each side of the outer end of the extension section, and wherein said attachment means includes a male element at each side of said further extension section, each male element being insertable in one of said female elements when said further extension section is in the usable position.

Claim 13

Crane structure as set forth in claim 10 wherein said mounting means further includes pin means for releasably retaining said male elements in said female elements.

Claim 14

Crane structure as set forth in claim 7 wherein said pivot axis is provided by aligned openings in said attachment means and connection means.

Claim 15

Crane structure as set forth in claiM 7 wherein said extension section and said further extension section include identical connection means and attachment means, respectively, at opposite sides thereof.

Claim 16

Crane structure as set forth in claim 13 wherein the connection means and attachment means on the side of said extension section and further extension section opposite from said pivot axis define the means for releasably retaining the further extension section in the usable position.