DESC:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
AND
The Patents Rules, 2003

COMPLETE SPECIFICATION
(Section 10 and Rule 13)

TITLE
A SYSTEM TO PREVENT IMPACT OF BODY ON MAINFRAME OF A VEHICLE

APPLICANT
(a) BEML LTD.
(b) An Indian Company,
(c) BEML Soudha,
No 23/1, IV Main, Sampangiramanagar,
Bengaluru, Karnataka, India

PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.
FIELD OF THE INVENTION
This invention relates to a system to prevent impact of body on mainframe of a vehicle. Particularly this invention relates a system to prevent the impact of a dump body on mainframe of a truck / dump truck while lowering the dump body and in turn avoids failures of structural components due to body impact.
STATE OF THE ART IN THE FIELD
Dump trucks are known in the art and are used for transporting construction materials, excavated earth and rocks material from working site to a dump yard. The dump trucks comprise a slow return valve arrangement to bring the dump body back on main frame / chassis of the vehicle / truck in a controlled manner within a predefined time duration of 18 seconds.
There are disadvantages associated with the conventional system. One of the disadvantages with the conventional system is that the existing slow return valve the body is lowering at little high speed causing an impact on the mainframe / chassis resulting in failures of structural aggregates.
Another disadvantage associated with the conventional system is that the maintenance cost of the truck is increased.
Yet another disadvantage associated with the conventional system is that the durability of the truck is reduced.
OBJECTS OF THE INVENTION
Therefore, an object of the present invention is to provide a system to prevent impact of body on mainframe of a vehicle which obviates the disadvantages associated with conventional system.
Another object of the present invention is to provide a system to prevent impact of body on mainframe of a vehicle having additional cushioning so as to provides smooth and non-impact type body lowering.
Yet another object of the present invention is to provide a system to prevent impact of body on mainframe of a vehicle and therefore enhances the durability of structural aggregates.
Still another object of the present invention is to provide a system to prevent impact of body on mainframe of a vehicle which is capable to extend the controlled action at the last stage of the hoist cylinder while lowering the dump body without affecting the cycle time.
A further object of the present invention is to provide a system to prevent impact of body on mainframe of a vehicle which provides safety to structural components during hitting impact type body lowering.
SUMMARY OF THE INVENTION
According to this invention there is provided a system to prevent impact of body on mainframe of a vehicle comprising a pump to supply hydraulic oil from the hydraulic tank to a right hand side multistage hoist cylinder and also to a left hand side (LHS) multistage hoist cylinder through a hoist control valve provide for raising / lifting and / or lowering the dump body as and when required and means comprising cushioning manifold with built-in an orifice and a pilot line being provided to prevent impact of dumper body on the mainframe of the vehicle during lowering to rest on the main frame of the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
A system to prevent impact of body on mainframe of a vehicle according to a preferred embodiment of this invention is herein described and illustrated in the accompanying drawings, wherein;
Figure – 1, Illustrates block diagram of a system to prevent impact of body on mainframe of a vehicle.
DETAILED DESCRIPTION OF THE INVENTION
A system to prevent impact of body on mainframe in the vehicle is herein described and illustrated with numerous specific details so as to provide a complete understanding of the invention. However, these specific details are exemplary details and should not be treated as the limitation to the scope of the invention. The invention may be performed with slight modifications. Throughout this specification the word “comprise” or variations such as “comprises or comprising”, will be understood to imply the inclusions of a stated element, integer or step, or group of elements, integers or steps, but not the exclusions of any other element, integer or step or group of elements, integers or steps.
Referring to drawings, figure 1, a system to prevent impact of body on mainframe of a vehicle, for example a dump truck is shown. The system comprises a pump (1) to supply hydraulic oil from the hydraulic tank (2) to a right hand side (RHS) multistage hoist cylinder (3) and also to a left hand side (LHS) multistage hoist cylinder (4) through a hoist control valve (5) provide for raising / lifting and / or lowering the dump body (not shown) as and when required in a controlled manner so as to drop the material contained in the dump body. The multistage hoist cylinders (3 & 4) comprises, for example, three stage telescopic type hoist cylinder. According to an embodiment of this invention means, comprising cushioning manifold (6), built-in orifice (7) and a pilot line (8), are provided to prevent impact of dumper body on the mainframe of the vehicle during lowering of the dumper body to rest on the main frame of the vehicle. The cushioning manifold (6) is provided between slow return valve (9) and the hoist control valve (5) such that to control the movement of the dumper body during lowering stage in a controlled manner and without any kind of hitting impact on the main frame / chassis of the vehicle / truck. The orifice (7) is provided in the cushioning manifold (6) to facilitate exit of the hydraulic oil during third stage of hoist cylinders (3 & 4) as and when body lowering is done. The pilot line (8) is provided between the multistage telescopic type cylinders (3 & 4) and cushioning manifold (6). An outlet (10) is provided with the cushioning manifold (6) to facilitate exit of the oil therefrom to tank as and when body lowering is done.
During operation of the system the hoist control valve (5) acts like a direction control valve and is provided to supply hydraulic oil to the multistage telescopic type cylinders (4) so as to raise and lower the dump body. The cushioning means keep the oil path of the cushioning manifold fully OPEN and keep it fully OPEN during lowering of the dump body until two stages of hoist cylinders (3 & 4) closes. The rate at which dump body lowers until two stages of hoist cylinders (3 & 4) will be governed by slow return valve (9). But during the last stage of closing of the hoist cylinders (3 & 4), a solenoid valve provided in the cushioning manifold (6) gets actuated and restricts the oil path in such a way that free path is closed with the influence of pilot line (8) taken from pressure line and allows the complete oil to pass through an orifice (7) in-built in the cushioning manifold to achieve smooth landing of dump body on mainframe / chassis of the vehicle.
Certain features of the invention have been described with reference to the exemplary embodiments. However, the description is not intended to be construed in a limiting sense. Various modifications of the exemplary embodiments as well as other embodiments of the invention, which are apparent to the persons skilled in the art to which the invention pertains, are deemed to lie within the spirit and scope of the invention.
,CLAIMS:WE CLAIM:
1. A system to prevent impact of body on mainframe of a vehicle comprising a pump (1) to supply hydraulic oil from the hydraulic tank (2) to a right hand side (RHS) multistage hoist cylinder (3) and also to a left hand side (LHS) multistage hoist cylinder (4) through a hoist control valve (5) provide for raising / lifting and / or lowering the dump body (not shown) as and when required and means comprising cushioning manifold (6), an built-in orifice (7) and a pilot line (8) being provided to prevent impact of dumper body on the mainframe of the vehicle during lowering of the dumper body to rest on the main frame of the vehicle.
2. The system to prevent impact of body on mainframe of a vehicle as clamed in claim 1, wherein the multistage hoist cylinders (3 & 4) comprises, for example, three stage telescopic type hoist cylinder.
3. The system to prevent impact of body on mainframe of a vehicle as clamed in claim 1, wherein cushioning manifold (6) is provided between the slow return valve (9) and the hoist control valve (5) such that to control the movement of the dumper body during lowering of third stage in a controlled manner and without any kind of hitting impact on the main frame / chassis of the vehicle / truck.
4. The system to prevent impact of body on mainframe of a vehicle as clamed in claim 1, wherein the orifice (7) is provided in the cushioning manifold (6) to facilitate exit of the hydraulic oil from the hoist cylinders (3 & 4) as and when dump body lowering is carried out during third stage
5. The system to prevent impact of body on mainframe of a vehicle as clamed in claim 1, wherein the pilot line (8) is provided between the multistage telescopic type cylinders (3 & 4) and cushioning manifold (8).
6. The system to prevent impact of body on mainframe of a vehicle as clamed in claim 1, wherein an outlet (10) is provided with the cushioning manifold (6) to facilitate exit of the oil therefrom as and when required.
Dated this 18th day of February, 2020

R. P. Yadav
IN/PA – 954
of sr4ipr Partners
Applicant’s Attorney