FIELD OF INVENTION:
The present invention relates to a remote control valve linkage mechanism, which can
be used in a pick-and-carry type of mobile hydraulic crane.
BACKGROUND OF INVENTION:
The present invention relates to a remote valve linkage mechanism which can be used
in a pick-and-carry type of mobile hydraulic crane, which improves the safety of operator,
reduces heat and noise and, also improves the cabin aesthetically.
In the known control valve system operation for pick and carry type of mobile
hydraulic crane, the main valve is mounted near the driver seating area just below the
operating lever very near to operator. The hoses from the valve go to the bulk plate in the
cabin & from there its goes to the respective operations. This is required as there is
articulation movement.
The main disadvantage of the present control valve system is hydraulic control valve
block is mounted very near to operator posing hazard from very hot hydraulic oil flowing
continuously in the hydraulic hoses during machine operation. This makes operator being
constantly exposed to highly risky hydraulic oil. The hoses inside cabin increase further risk
from very hot hydraulic oil injury in case of hose failure
However in some of the existing control valve linkage mechanism, this valve and
hoses are made isolated with a partition inside cab. However such arrangement eats up the
space inside cab. Therefore this concept is major a constraint in specious cab design.
Another major disadvantage with existing control valve linkage mechanism is that,
the control valve lay open inside cab, thru' which oil spillage & other leakages remains
present inside cab during servicing or replacement of control valve, hydraulic hoses &
hydraulic fittings.

Another disadvantage of existing control valve linkage mechanism is the problem
associated with the attending or handling the control valve & related assembled components
i.e. relief valve, hydraulic hoses, hydraulic fittings in the limited space available around the
control valve mounting area.
Yet another disadvantage of the present control valve linkage mechanism is, that
valve block is operated through short levers this increases lever effort and reduces precision
of control
Yet another disadvantage of the present control valve linkage mechanism is, that the
hydraulic oil needs to circulate through more hoses thus heating more through friction
Yet another disadvantage of the present control valve linkage mechanism is, the
Hydraulic valve & hydraulic oil routing inside cab increases cab noise & temperature
Therefore, in view of the disadvantages stated above, the main objective of the
present invention is hydraulic control valve block is mounted outside the cabin thus
eliminating any chance of injury due to hot hydraulic oil.
Another objective of the present invention is, this mechanism requires no hoses inside
cabin thus increasing further safety from injury from very hot hydraulic oil incase of any hose
failure.
Another objective of the present invention is, the valve block is operated through
lever mechanism which reduces lever efforts & increases precision of control.
Another objective of the present invention is, the hydraulic oil directly routes to
Hydraulic cylinders without need of extra long hoses inside cabin thus preventing
overheating through friction

Yet another objective of the present invention is, that without any hydraulic valve &
hoses inside cabin; temperature and noise inside the cabin is reduced.
Further objective of the present invention is, this mechanism uses less no of parts
and cost for hydraulic control system.
We shall now describe the invention with reference to accompanying drawings which
are given for the sake of illustration, but do not restrict the scope of present invention.
Referring to drawings:-
Fig. 1 shows prior art hydraulic system for pick and carry type of mobile hydraulic
cranes
Fig. 2 shows prior art hydraulic system for pick and carry type of mobile hydraulic
cranes
Fig. 3 shows new remote control valve linkage mechanism of the present invention.
According to present invention there is provided an remote linkage mechanism for a
hydraulic valve as shown in Figure 3, block (5) and lever (8) are welded to the shaft (6) to
form a winch control assembly (9). Similarly extension control assembly (10), lift control
assembly (11) and steering control assembly (12) are also made.
Control assembly (9), (10), (11) and (12) are assembled together using four numbers
or more nylon bushes (7).
Lever Steering (1), lever lift (2), lever extension (3) and lever winch (4) are assembled
to block (5) of respective control assembly using locknut.
Rods (13), (14), (15) and (16) are assembled to lever (8) of respective control
assembly at one end and to respective spool on main valve at other end through fork and pin.

When lever winch (4) is moved in forward direction, winch control assembly (9)
rotates about its axis on the nylon bush (7), lever (8) moves in downward direction; this
pushes the winch rod (16) downwards which in turn presses the winch spool in main valve
(17) downwards.
When lever winch (4) is moved in reverse direction, winch control assembly (9)
rotates about its axis on the nylon bush (7), lever (8) moves in upward direction, and this
pulls the winch rod (16) upwards which in turn pulls the winch spool in main valve (17)
upwards.
Other spools are operated in a similar manner, by the respective levers (1), (2) and (3).
To obviate such constraints in designing a spacious, comfortable and a safe operator
environment inside the cabin, some of the construction equipments widely categorized as
slew crane, backhoe loaders, excavators use one or the other concept of remote control valve
linkage mechanism.
The background of invention is aimed at achieving the vary advantages of new design
remote control valve linkage mechanism suitable for pick and carry type of mobile hydraulic
cranes.
The background of invention also aimed at achieving the cost effective, easy to
operate, and with an ease of manufacturability remote linkage mechanism for pick and carry
type of mobile hydraulic cranes.