The present invention relates to An improved Compact Yoke Structure on
Mobile Crane Machine and more paliicularly an improved compact Yoke
structure on mobile Pick and CallY type of cranes and more paliicularly relates
to an efficient and compact Yoke stmcture on Pick and Carry type of Hydraulic
mohile cranes.
BACKGROUND OF THE INVENTION:
In the known art pick and cany types of mobile hydraulic cranes, many steel
welded structures are fitted together to fOlln the chassis in the useful manner to
enable the crane perfonn required function ofload lifting and traveling with and
without load.
Figs I and 2 of the accompanying drawings illustrate one such known compact
yoke structure. In the said figures, the yoke structure (8) is mounted on another
structure known as cradle (7). The tractor unit of crane is having allOther chassis
(10) structural member on which engine, transmission, axle, cab (12) and
counter weight (I I) are fitted. The tractor unit is pinned to cradle (7) on which
futiher yoke (8) is also fitted. While another structure mounts boom and is
known as main frame (6). The main fi'ame (6) is connected at one end to yoke
(8) at upper side. While another member know as A Frame (5) connects cradle
(7) and Main frame (6). These all members joined together perfonn the function
for crane operation; Refer figure ] and 2.
2
In the known prior att in industty pick and cany type mobile cranes as describe
in figure I have hydraulic and diesel tanks (9) mounted in fi'ont of the driver
cabin (12) on the tractor unit. Both these tanks (9) occupy space in the area
Yoke (8) stlUcture as required in the known crane layout.
\n the said configuration the yoke (8) stt'ucture in crane layout in figure 1 and 2
has a top beam (\ a) as shown in figure 3. This top beam has length more from
both the diesel and hydraulic tank width to accommodate them under the top
beam. Futther the top beam (Ia) member is connected by two side members
(2a) in a invetted V shape on both sides of beam. Thus Yoke structure has four
side members connected with top beam two on each side. These inverted V
slwpc member (2a) are fixed with Top beam member (la) of yoke (8) in such a
way that the tanks (9) remain below the top beam and inside invetted V shape
side members. Refer figure 3.
A disadvantage of the said anangement is that such a consttuction of Yoke
mounted in crane layout on space above the tanks; top beam of yoke is longer in
length and invetted V shape side members are more in height.
Another disadvantage of this arrangement is that since invetted V shape side
members need to be more in height this reduces buckling strength of yoke
structure.
Yet another disadvantage of this anangement is that since top beam member
need to be more in length this reduced bending stt'ength of yoke structure.
-'",'
Yet another disadvantage of this anangement is that to increase bucking
strength of side invet1ed V shape members and bending strength of top beam
member steel with more thickness is required which using more material to
construct the Yoke shucture. This increases weight of Yoke shUcture and
increases cost.
To overcome disadvantage of this crane layout and to have a more efficient
crane structure a compact yoke anangement is described along with placement
of hydraulic and diesel tanks outside of Yoke shucture.
OBJECT OF THE INVENTION
It is therefore, object of the invention to develop compact yoke structure which
obviates disadvantages ofpJior art discussed above.
Another object of the present invention there is provided an improved and more
efficient as well as an economical crane structure having compact yoke
anangement which overcomes disadvantages mentioned above.
To overcome disadvantage of this crane layout and to have a more efficient and
economical crane structure a compact yoke anangement is described along with
placement of hydraulic and diesel tanks outside of yoke stmcture.
At the outset of the description which follows, it is to be understood that the
ensuring description only illustrates a pat1icular fonn of its invention. Howevec
such a pm1icular form is only an exemplary embodiment and without intending
to be understood as an exemplary embodiment and teaching of the invention
and not intended to be taken restrictively.
The nature of the invention, its object and fut1her advantages residing in the
same will be apparent ft-omthe following description made with reference to the
non-limiting exemplary embodiment of the invention represented in the
accompanying infonnal drawing and pm1icularly figures 3 and 4.
An improved layout of crane involves in placement of diesel and hydraulic
tanks (9) outside the Yoke structure (8) members as shown in Figure I and 2; In
such configuration of crane layout the space inside the Yoke structure that is
earlier occupied by diesel and hydraulic tanks is available for utilization of other
purposes.
In order to overcome earlier described disadvantages of Yoke structure with
long top beam member and more in height side inve11edV shape members, an
efficient and compact yoke structure follows with narrow length top beam (I b)
member.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
We shall now describe the present invention with reference to accompanying
drawings and particularly figures 3 and 4 which are given by way of illustration
but which does not restrict scope of the present invention.
Refening to drawings:-
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Fig.) shows PRIOR ART Pick and carry crane layout showing major structural
elements;
Fig 2 shows Pick and Cany crane layout showing application of the modified
Yoke;
Fig.3 shows Plior A11Yoke structural member;
Fig.4 shows New Compact Yoke Structural Member.
DESCRIPTION OF THE INVENTION
According to the present invention there is provided an improved Compact
Yoke Structure on Mobile Crane Machine comprises of steel profiled plates
welded to fonn an integrated fabricated structure consisting of the top beam and
four side members along with gussets to strengthen joints of top beam and side
members and the said two side members forming an invel1ed V shape are placed
on both sides of top beam wherein the two side members fonning an inverted V
shape at both sides of top beam are bent so as to achieve a nan'ow spacing on
top which accommodates top beam of sh0l1er length.
Rib gussets inside side bent members and top beam which are provided at both
front and rear sides of yoke stmcture.
An exclusive rib gussets are provided outside at both sides of yoke structure
wherein the side bent members join in shape of invel1ed Vat the top.
Along with placement of diesel and hydraulic tanks outside the yoke structure
members wherein leaving outside space above the hydraulic and diesel for other
requirements and mounting other equipment for applications for crane
operation.
Forms part of an integrated and improved layout of pick and cany type of
hydraulic mobile cranes.
Etlicient and Compact Yoke Structure on Mobile Crane Machine, the four side
members of Yoke structure are having a bend across the height. Two of these
bend side members are connected on each side of top beam. These bend
members placed on each side of top beam thus fonn an inverted V shape.
These bent invel1ed V shape members (2b) are further fixed with naITOWtop
beam member (I b) on each side as shown in Figure 4. These bend side members
thus fonTIshape of inve11edV. The side members are thus wider at bottom (1b)
for connection with cradle stmcture (7) and naITOWat top on crane assembly.
FU1therto the present invention these bend side inve11edV shape members have
a profiled gusset (3b) that is fixed on inside of each bend side member (2b) and
to the top with top beam member (I b). Such a placement of profiles gussets
provides yoke structure with sufficient strength to perfonn work in crane layout.
FUlther another gusset (4b) is placed outside of bend inverted V shaped
members (2b) for joining them together each side of nalTOWbeam where bend
invel1ed V member joins top beam sides.
The yoke (8) structure thus produced has reduced thickness of steel material to
manufacture top beam which is very narrow in length. This results in Top beam
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with a highly improved resistance to bending. This resistance to bending is a
result of nanow length of top beam member.

1. An improved Compact Yoke Structure on Mobile Crane Machine
compnses of steel profiled plates welded to fonn an integrated fabricated
structure consisting of the top beam and four side members along with gussets
to strengthen joints of top beam and side members and the said two side
members fanning an inverted V shape are placed on both sides of top beam
wherein the two side members fonning an invel1ed V shape at both sides of top
beam are bent so as to achieve a nan"ow spacing on top which accommodates
top beam of sh0l1er length.
2. An improved Compact Yoke Structure on Mobile Crane Machine as
claimed in claim 1, wherein rib gussets inside side bent members and top beam
are provided at both front and rear sides of yoke structure.
3. An improved Compact Yoke Structure on Mobile Crane Machine as
claimed in claim I, wherein an exclusive rib gussets are provided outside at
both sides of yoke structure wherein the side bent members join in shape of
invel1ed V at the top.
4. An improved Compact Yoke Structure on Mobile Crane Machine as
claimed in claim 1. wherein along with placement of diesel and hydraulic tanks
outside the yoke structure members are provided wherein leaving outside space
above the hydraulic and diesel for other requirements and mounting other
equipment for applications for crane operation.
5. An improved Compact Yoke Stmcture on Mobile Crane Machine as
claimed in claim ], which fonns part of an integrated and improved layout of
pick and carry type of hydraulic mobile cranes.