FIELD OF INVENTION
This invention relates to a mother boom having a single or a plurality of boom sections. By way of example, the boom of the present invention can advantageously in a crane.
BACKGROUND OF INVENTION
Telescopic booms for use in a crane are known in the art and whereby the operating length of the boom can be increased or decreased. In such a construction, the extended boom is slidably or telescopically disposed with respect to the mother boom. A multistage or multiple cylinders are provided for actuating the extended boom.
OBJECTS OF THE INVENTION
An object of this invention is to propose a novel construction of motive means for the extended sections of a boom.

Another object of this invention is to propose a boom which can have a short length during movement of the crane.
Still another object of this invention is to propose a construction of a boom which is compact and has a minimum overhang during movement of the crane.
Yet another object of this invention is to propose a boom for use in a crane which is efficient.
Further objects and advantages of this invention will be more apparent from the ensuing description.
STATEMENT OF THE INVENTION
According to this invention there is provided a fully powered four parts extendable boom for a. crane comprising (a) a mother or main boom; (b) at least ore and upto three boom sections slidably disposed within said mother boom; (c) power means for actuating said boom section; (d) said power means comprising a

hydraulic cylinder actuated by a motive source; (e) said hydraulic cylinder having a movement and held to the first boom section.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings and wherein:
Fig. 1 shows: extension of first boom section with boom cylinder.
Fig.2 shows: extension of second boom section with extension
rope.
Fig. 3 shows: extension of thire boom section with extension
rope.
DETAILED DESCRIPTION WITH REFERENCE TO ACCOMPANYING DRAWINGS:-

In accordance with this invention, the fully powered boom as shown in fig. 1 comprises a main or mother boom (3) with at least one boom section (1) that can be easily disposed within the mother boom. To extend the boom section, a cylinder (4) is

adapted to be held to the boom section, and such that axial movement of the cylinder results in a corresponding movement of said boom section. The cylinder is adapted to move along a rod (5), held to the mother boom. The main boom is having an anchor point (2) for one end of the cylinder (4) to be anchored with. The cylinder can be hydraulically operated so as to cause a retraction or extension of said boom section.
In accordance with another embodiment of this invention ( as shown in fig. 2 and 3), the boom comprises a second and third boom section (5 and 4) and such that the hydraulic means for the first boom section results in a corresponding movement of the second and third boom sections.

For this purpose with particular reference to fig. 2 one or proximal end (1) of a pair of rope is held to the proximal end of said mother boom (2) and extends over a pair of pulleys (4) mounted on the distal end of the slidable telescopic cylinder (3) and then anchored to the proximal end (5) of the second boom section (5). Thus, a movement of the cylinder results in a simultaneous movement of the second boom section.
In accordance with this invention and referring to fig. 3 a third boom section (4) is provided with said mother boom and such that a movement of the cylinder results in a movement of the first, second and third boom sections (2, 3 and 4). For this purpose a second pair of rope |6) is anchored to the proximal end of said first boom section and extends over the length of said first boom section and passes over a pair of pulleys (5) mounted on the distal end of said second boom section and to the proximal end (5') of said anchored third boom section.

It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims: -

WE CLAIM:
1. A fully powered four parts extendable boom for a crane
comprising:
(a) a mother or main boom;
(b) at least one and upto three boom sections slidably disposed within said mother boom;
(c) power means for act mating said boom section;
(d) said power means comprising a hydraulic cylinder actuated by a motive source;
(e) said hydraulic cylinder having a movement and held to the first boorn section.
2. A fully powered four paris extendable boom as claimed in
claim 1 wherein proximal and of said second boom section
is anchored to one end of a pair of rope, other end of
which is held to the proximal end of a main boom and
extends over a pair of palieys mounted on the distal end
of the telescopic cylinder

3. A fully powered four parts extendable boom as claimed in claim 1 wherein, proximal end of said third boom section is anchored with a second pair of rope, other end of which held to the proximal end of said first boom section and extends over the length of said first boom section and passes over a pair of pulleys mounted on the distal end of said second boom section.
4. A fully powered four parts extendable boom as claimed in any of the preceding claims wherein the cylinder is held to the first boom section.
5. A fully powered four parts extendable boom for a crane substantially as herein described with reference to accompanying drawings.