Back to results
US 6,474,486 B1Granted
Method of telescoping a crane jib, apparatus for implementing the method, and a crane jib constituting an application thereof
AssigneeP P M
InventorRobert Baraniak
Life of this patent
Estimating the term…
Abstract
The invention relates an apparatus for hoisting and handling equipment wherein the apparatus includes locking members having a locking block (30) carried by each telescopic element and including clamping member which is clamped in a rest position, an immobilization piece (40) carried by each element outside the element carrying a block configured to cooperate with the clamping member.
Claims42
A method of telescoping a crane jib comprising a base element, at least one intermediate element and an end element placed in mutual bearing relationship by centering spacers, the method comprising the steps of:
- implementing an actuator for providing rectilinear displacement in opposite directions which is disposed inside the jib and which is connected to the base element of the jib;
- implementing on each element other than the base element a locking block comprising a clamping member movable between a clamped rest position and an unclamped position;
- causing the clamping member of each block to clamp at least one fixed-position immobilization piece belonging to the element disposed concentrically outside the element carrying the block;
- implementing on the actuator a driver member moving an engagement member suitable for acting selectively on each of the locking blocks and movable between a retracted position and an extended position such as:
- when moving from the retracted position to the extended position the engagement member firstly engages the locking block in order to connect the actuator to the block and secondly makes the clamping member moving from the clamped rest position to the unclamped position in order to unlock the locking block from the fixed-position immobilization piece;
- and when moving from the extended position to the retracted position the engagement member firstly makes the clamping member moving from the unclamped position to the clamped rest position in order to lock the locking block on the fixed-position immobilization piece and secondly disengages the locking block in order to release the actuator from the locking block.
3 more elements
An apparatus for telescoping a crane jib comprising a base element, at least one intermediate element and an end element, the apparatus comprising:
- an actuator for rectilinear displacement in both directions to connected inside the jib to a base element thereof, the actuator having a telescoping head;
- for each telescopic element other than the base element, a locking block comprising a clamping member movable between a clamped rest position and an unclamped position;
- for each telescopic element other than the end element, at least one immobilization piece to be fixed on said telescopic element, the immobilization piece being designed to co-operate with the clamping member of the locking block;
- driver means to be adapted on the telescoping head to displace an engagement member suitable for acting selectively on each of the locking blocks and movable between a retracted position and an extended position such as:
- when moving from the retracted position to the extended position the engagement member firstly engages the locking block in order to connect the telescoping head to the block and secondly makes the clamping member moving from the clamped rest position to the unclamped position in order to unlock the locking block from the fixed-position immobilization piece;
- and when moving from the extended position to the retracted position the engagement member firstly makes the clamping member moving from the unclamped position to the clamped rest position in order to lock the locking block on the fixed-position immobilization piece and secondly disengages the locking block in order to release the telescoping head from the locking block.
3 more elements
A crane jib comprising:
- a base element, at least one intermediate element and an end element placed in mutual bearing relationship by centering spacers;
- an actuator for rectilinear displacement in both directions, the actuator being inside the jib and connected to the base element and having a telescoping head;
- a locking block carried by each element other than the base element, the locking block comprising a clamping member movable between a clamped rest position and an unclamped position;
- at least one immobilization piece of fixed position on each telescopic element other than the end element and designed to co-operate with the clamping member of the locking block;
- driver means adapted on the telescoping head to displace an engagement member suitable for acting selectively on each of the locking blocks and movable between a retracted position and an extended position such as:
- when moving from the retracted position to the extended position the engagement member firstly engages the locking block in order to connect the telescoping head to the block and secondly makes the clamping member moving from the clamped rest position to the unclamped position in order to unlock the locking block from the fixed-position immobilization piece;
- and when moving from the extended position to the retracted position the engagement member firstly makes the clamping member moving from the unclamped position to the clamped rest position in order to lock the locking block on the fixed-position immobilization piece and secondly disengages the locking block in order to release the telescoping head from the locking block.
4 more elements
Dependencies are inferred from the claim text.