FORM 2
THE PATENT ACT, 1970 (39 of 1970)
&
THE PATENTES RULES, 2005
PROVISIONAL SPECIFICATION
(See section 10. rule 13)
1. TITLE OF THE INVENTION
"A Tilting Mechanism for Tilting Cargo Bed of a Vehicle"
2. APPLICANT(S)
(a) Name : MAH1NDRA & MAHINDRA LIMITED
(b) Nationality : Indian Company registered under the provisions
of the Companies Act, 1956
(c) Address : R&D Center, Automotive Sector,
89, M.I.D.C, Satpur, NASHIK - 422 007
Maharashtra State, India

3. PREAMBLE OF THE DESCRIPTION
PROVISIONAL
The following specification describes the invention

A Tilting Mechanism for Tilting Cargo Bed of a Vehicle
Field of the invention
The present invention is related to a tilting mechanism for tilting the cargo bed (goods container) of light commercial vehicles (LCVs) manually with respect to the chassis of the vehicle for maintenance.
Background of the invention
Cargo bed of a vehicle needs to be tilted about a transverse axis from normal operating position to inclined position to get access of the parts coming under cargo bed, such as battery pack on electric vehicle which requires maintenance of batteries at regular intervals. Various mechanisms are available to tilt the cargo bed of the vehicle with respect to chassis. Most of them are hydraulically operated systems which are meant for unloading the material from a loaded cargo bed. These systems consist of piston-cylinder arrangement mounted between the cargo (moving body) and chassis (stationary). Hydraulic fluid pump creates fluid pressure because of which piston moves up and down. Some other systems are there which uses electric motor or gear mechanism which works on the concept of screw jack or rack & pinion gear arrangement. Hydraulic lifter is the most popular one out of these because of its ergonomic aspects. But some economy trucks have cargo (goods container) behind the drivers cabin which needs to be lifted manually only to access the parts coming under the cargo and not for unloading the material from the cargo.
Prior art for the invention
US PATENT NO. 3617090 explains the tilting of a truck bed tilting mechanism which is used between the hauling bed and frame of a truck having a bed pivotally connected adjacent the rear of truck frame to permit relative rotation between the

hauling bed and frame. The tilting mechanism comprises of a multi-bar linkages (two or three interconnected links or more). A hydraulic ram is used to raise the linkages. By unfolding the linkages tilting bed is raised to the tilted position.
US Patent No.4066296 discloses the tilting mechanism for an overhauling bed pivotally connected to the frame of the vehicle. This mechanism also has the variable length hydraulic actuator which causes the folding and unfolding of the mechanism and hence tilt the truck bed. This mechanism comprises of four connected arms. First arm is connected to the frame: second one is connected to the bed and a third and fourth arm are connected between first and second arms and makes a parallelogram.
Deficiencies of the prior art
• All the patents listed in the prior art, tilting mechanism requires a pump to
actuate the fluid pressure inside the hydraulic ram.
• All the patents listed in the prior art have automated systems of cargo
tilting which requires power source to run the pump.
• All the systems are heavy which adds weight to the vehicle hence affects
the fuel economy.
• Also these systems occupy huge space under the cargo or bed of a truck
which affects the mountings for engine, transmission or battery pack.
• The hydraulic pump and hydraulic actuators used therein adds cost to the
vehicle which is not justified for the maintenance or servicing purpose only.
• The hydraulic ram and the system require maintenance at regular intervals.

Object of the present invention
Object of the present invention is to provide a tilting mechanism for tilting a cargo bed with respect to a chassis of a vehicle, which does not require any power source.
Another object of the present invention is to provide a tilting mechanism for tilting a cargo bed with respect to a chassis of a cargo vehicle, which is easy and safe to operate.
Yet another object of the present invention is to provide a tilting mechanism for tilting a cargo bed with respect to a chassis of a vehicle, which is operated manually with lesser efforts.
Further object of the present invention is to provide a tilting mechanism for tilting a cargo bed with respect to a chassis of a vehicle, which requires lesser time to lilt the cargo as compared to the mechanism of the prior art.
Yet another object of the present invention is to provide a tilting mechanism for tilting a cargo bed with respect to a chassis of a vehicle, which enables easy access to the engine, battery pack to facilitate servicing and other operation.
Another object of the present invention is to provide a tilting mechanism for tilting a cargo bed with respect to a chassis of a vehicle, which is economical in construction and light in weight.
Brief description of the invention
Further objectives and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein,

Figure 1 shows the side view of a chassis and a cargo bed in accordance with the present invention;
Figure 2 shows the side view of the present invention when the cargo bed is at fully tilted condition with respect to the chassis; and
Figure 3 shows the isometric view of figure 2.
Description of the invention:
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with the prior art techniques and approaches are overcome by the present invention as described below in the preferred embodiment.
The present invention provides a tilting mechanism for tilting the cargo bed. The tilting mechanism enables tilting the cargo bed at a pre-defined angle manually. Further, the tilting mechanism includes a gas strut and mechanical linkages for tilting the cargo bed. The tilting mechanism is preferably used for light commercial vehicles generally having payload capacity upto 1.5 tones. However. it can be successfully employed in the vehicles with the payload capacity greater than 1.5 tones. The light commercial vehicles usually have a driver's cabin at the front and a cargo bed mounted on a back portion of the chassis. Engine and a transmission partly come under the driver's cabin and partly come under the cargo bed. If it is an electric vehicle then there will be a big rectangular battery box containing number of batteries below the cargo bed. Also. most of the time complete drive system is disposed under the cargo if it is a rear wheel drive vehicle. For the maintenance purpose, access of the above mentioned parts is

required. For the purpose of maintenance of under-cargo systems/components, the cargo bed needs to be tilted,
This present invention is illustrated with reference to the accompanying drawings. throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.
Referring now to figure 1 shows the side view of a chassis (6) and a cargo bed (7) with the tilting mechanism (not numbered) in accordance with the present invention. Generally, a vehicle includes a cargo bed (7) and a chassis (6), The cargo bed (7) shown in horizontal (normal running) position is pivoted at the rear end of the chassis (6) for tilting with the help of a plurality of hinges (4). The cargo bed (7) is tilted from the hinge (4). In the normal running condition cargo bed (7) is positioned by means of a plurality of locators (12) which are fastened to the chassis (6) mountings and inserted into the mating holes on the cargo body mountings. In an embodiment, the locator (12) is a stud secured to the chassis (6) and a matching slot on the cargo bed (7). This arrangement restrict the cargo movement in horizontal plane..The locators (12) restrict movement of the cargo bed (7) with respect to the chassis (6). A toggle latch (11) is provided to clamp the cargo bed (7) with the chassis (6) in running condition of the vehicle.
The present invention includes a plurality of gas struts (1). a plurality of lower links (2) hingeably connected to a plurality of upper links (3) at poini (9). The upper links (3) are hingeably secured to the cargo bed (7) at points (8). The lower link (2) is hingeably secured to the chassis (6) at points (5). The gas strut (I) is hingeably secured to the point (13) and the other end of the gas strut (I) is secured to the lower link (2) at points (10). The upper link (3), the lower link (2). the cargo bed (7) and the chassis (6) configures a four bar mechanism having hinge points at (4), (8), (9) and (5).

The gas strut (1) includes a cylinder filed with nitrogen gas. a piston with a piston rod. It requires external force to be applied at both ends to get the gas compressed. The compression and expansion of the nitrogen gas enables retraction and extension of the piston rod therethrough. This property of the gas strut (I) is used to assist manual tilting of the cargo bed (7). Further, the orientation of the gas strut (1), the lower link (2) and the upper link (3) is kept such that while lifting the cargo bed (7) manually from the front end, initially small amount of manual effort is required which goes on decreasing up to a certain point and after that becomes negative that means cargo bed (7) goes up due to the expansion of (he gas in the gas strut (1) which reduces manual efforts. The piston of the gas strut (!) is extended to the maximum for tilting the cargo bed (7) (refer figure 2 & 3)
Further, for bringing the cargo bed (7) down to secure with the chassis (6). the cargo bed (7) can be slightly pushed/pulled down manually. Further, the cargo bed (7) can be pulled down by the gas strut (J) by compressing the air therein.
All hinged joints are provided with plastic bush to avoid metal to metal contact and for making smooth operation. The cylinder of the gas strut (1) is secured by female heim joint to the lower link (2). and ball joint is provided at the other end of the gas strut (1) to accommodate any undesirable non coplanar movement of links (2 & 3).
Figure 3 shows the isometric view of tilting mechanism in which the above mentioned mechanism is shown side by side fitted on the vehicle which facilitates the proper balancing of cargo bed (7) on the chassis (6).
Advantages of the present invention
Easy, quick and smooth operation of the mechanism.
Less amount of effort is required to lift the complete cargo body.
• Single person can operate the whole mechanism.

As it is a manually operated system, no external power source is required
which adds to the fuel efficiency.
• Less number of parts required.
As the complete mechanism is fitted outer side of the chassis. no additional space is required.
Facilitates complete access to the all components coming under the cargo body.
Suitable for low cost vehicles as the material cost is low compared to the other systems present for this application.
Safer in operation as it is operated from the side of the vehicle.
It should be understood that the present invention is not to be limited by the exact details of the illustrated embodiment. However, it is to be taken as the preferred example of the invention and that various changes may be resorted to by a person skilled in the art without departing from the spirit of the invention. Also. the terminologies used herein are for the purpose of description and should not be regarded as limiting.