Title of Invention | SLIDING TAILGATE ASSEMBLY FOR VEHICLES |
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Abstract | The present invention relates to the opening and closing mechanism of tailgates and more particularly to a sliding type tailgate for vehicles in which direct sliding up of the tailgate is not possible due to the design of the vehicle e.g. vehicles in which tailgates which arc not integral with the rear windscreen. The sliding tailgate assembly consists of a tailgate panel, a pair of guide channels provided on the tailgate panel, a lock unit with one part provided on the tailgate panel and another part on the vehicle rear, a pair of spring loaded struts fixed to the vehicle rear, a pair of rollers mounted at the end of each strut, at least two torsion spring loaded retainers on the tailgate within the guide channels, and a peg at the centre of the bottom face of the tailgate panel and a corresponding cavity is provided on the vehicle body to accommodate the said peg during normal closed position. In the closed position of the tailgate, the spring loaded struts are in a compressed state and the tailgate lock is engaged. When the tailgate lock is unlocked and the lock lever is pulled, the tailgate pops out to a small distance in order to prevent the interference with the rear windscreen while sliding and the tailgate can then be lifted upwards. |
Full Text | FORM 2 THE PATENTS ACT 1970 (39 of 1970) & THE PATENTS RULES, 2003 COMPLETE SPECIFICATION (See Section 10; rule 13) TITLE OF THE INVENTION SLIDING TAILGATE ASSEMBLY FOR VEHICLE APPLICANTS TATA MOTORS LIMITED, an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India INVENTORS Mr. Sachin Thakur and Mr.Preesty Thomas both Indian nationals of TATA MOTORS LIMITED an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India PREAMBLE TO THE DESCRIPTION The following Complete specification particularly describes the invention and the manner in which it is to be performed. FIELD OF INVENTION The present invention relates to the opening and closing mechanism of tailgates for vehicles and more particularly relates to a sliding type tailgate for vehicles. BACKGROUND OF INVENTION The present mechanisms of opening and closing for vehicle tailgates which are not integral with the rear windscreen are based on the hinge mechanisms with hinges at two ends of the tailgate, either in the horizontal or vertical axis. This mechanism of tailgate operation requires considerable space. Also, with there being a lot of demand for compact small cars it is necessary to have a compact tailgate operating mechanism. DE 3335699 describes tailgate on motor vehicles which is constructed as a sliding door and can be slid between a lower closed position and an upper limit position which exposes the loading opening, it being possible to lock the sliding door in the lower closed position and to hold it in the upper limit position. For the purpose of opening, the sliding door is therefore pushed upwards over the roof of the motor vehicle so that the loading opening and the loading space of the motor vehicle are freely accessible. Preferably, additionally spring-mounted compensation rollers are provided to compensate the weight of the door to permit easy manual operation of the sliding door. The above tailgate has limitations in cases for vehicles where due to aesthetic or other considerations the tailgate will not be able to slide directly upwards as it would interfere with the rear portion of the vehicle, more particularly when the 2 tailgate is not integral with the rear windscreen it would interfere with the rear windscreen while sliding up. The above shortcoming can be taken care of by having an extension mechanism for the tailgate which gives a free path for the tailgate to slide unhindered. OBJECTS OF INVENTION The main object of this invention is to provide a compact sliding type tailgate operating mechanism for vehicles. Yet another object of this invention is to provide a sliding type tailgate operating mechanism for vehicles which is simple in construction and cost effective. SUMMARY OF INVENTION The sliding tailgate assembly consists of a tailgate panel, a pair of guide channels provided on the tailgate panel, a lock unit with one part provided on the tailgate panel and another part on the vehicle rear, a pair of spring loaded struts fixed to the vehicle rear, a pair of rollers mounted at the end of each strut, at least two torsion spring loaded retainers on the tailgate within the guide channels, and a peg at the centre of the bottom face of the tailgate panel and a corresponding cavity is provided on the vehicle body to accommodate the said peg during normal closed position. In the closed position of the tailgate, the spring loaded struts are in a compressed state and the tailgate lock is engaged. When the tailgate lock is unlocked and the lock lever is pulled, the tailgate pops out to a small distance in order to prevent the interference with the rear windscreen while sliding and the tailgate can then be lifted upwards. 3 DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same, Fig. 1 shows a detailed cross-sectional view of the tailgate assembly in accordance with this invention. Fig. 2 shows a sectional view of the tailgate panel taken along the plane X-X from fig. 1 Fig. 3 shows the cross-sectional side view of the rear of a vehicle having a rear windscreen fixed to the vehicle and the tailgate assembly fitted in accordance with this invention. Referring to Fig 1, the tailgate assembly consists of a tailgate panel [1], one or more guide channels [2] provided on the said tailgate panel, a lock unit [3] with one part provided on the said tailgate panel and another part on the vehicle rear, one or more springs [4] provided on one or more spring loaded strut assemblies [5], one or more rollers [6] mounted at the end of each of the said strut assemblies , one or more torsion spring loaded retainers [7] provided on the said tailgate panel [1] within the said guide channels, and one or more pegs [8] are provided at the bottom face of the said tailgate panel. The lock unit [3] uses a conventional locking mechanism and has two parts, one part is integral with the said tailgate panel having a key slot provided so that the 4 unit can be locked from outside and also an engaging lever, and the second part is fitted to the vehicle body. The spring loaded strut assembly [5] consist of a piston cylinder arrangement wherein the cylinder is fixed and piston is movable, the said cylinder is mounted inside the rear compartment of the vehicle and piston is slidably fitted inside the said cylinder, the piston consists of a piston head and piston rod with the cross-section of the said piston head being greater than that of the piston rod. Also the end of the said cylinder is provided with a flange to prevent separation of the said piston from said cylinder and a spring is provided, one end of which is fitted rigidly to the said flange and the other end is fitted on the said piston rod through another flange. The spring stiffness is adjusted such that in the free state of the spring the strut extends as much as required for the sliding of the panel to take place without any interference from the fixed rear wind screen. The said torsion spring loaded retainer [7] is mounted inside a slot provided in the said guide channel [2] which would enable it to rotate through a right angle in both the directions and not provide any interference to the movement of the rollers [6] when a sufficient force is applied to the tailgate panel [1] in the direction of slide. The torsion spring stiffness is selected such that when the said tailgate panel is at its top most position the weight of the said tailgate panel is supported by the said torsion spring loaded retainer and on application of a force in the downward direction the said torsion spring loaded retainer rotates and lets the said tailgate panel to slide down. Fig 2 represents the sectional view along section X-X from fig. 1 showing the guide channel [2] and the manner in which the roller [6] is constrained in the said guide channel and mounted on to the strut [5]. The cross-section of the said 5 guide channel is such that the said roller does not come out of the said guide channel during normal operating conditions. Fig 3 shows the side view of the rear of a vehicle with the tailgate assembly, the extent of extension of the strut [5] Also, a cavity [9] is shown on the vehicle body at the bottom, this cavity is lined with a rubber grommet and the peg [8] is seated in this cavity when the tailgate panel [1] is in the closed position. This is to ensure low Noise, Vibration, Harshness (NVH) levels when the vehicle is in motion. In the closed position the tailgate is locked in its position by the lock unit, on opening the lock unit and pulling the lock lever the tailgate extends out. On lifting the tailgate, it slides upwards on the rollers. When the upper limit of travel is reached the roller passes over the spring loaded retainer in the guide channel and when the effort is removed the roller is prevented from passing over the retainer in the reverse direction due to the self weight of the tailgate panel. To close the tailgate, the tail gate is slid down to overcome the spring force of the retainer and the tailgate slides down on the rollers and on reaching the lower limit of travel the pushing of the tailgate engages the lock lever and can then be locked in that position. Also, for lesser effort in overcoming the torsion spring loaded retainer it is desirable that the leverage of effort is utilized by tilting the panel outwards when the retainer is encountered while sliding upwards and tilting the panel inwards when the retainer is encountered while sliding down. 6 The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof. 7 WE CLAIM: 1. Sliding tailgate assembly for vehicle comprising of a tailgate panel, a lock unit with one part provided on said tailgate panel and another part provided on the rear of vehicle, wherein the said tailgate panel is slidably fitted to the rear of vehicle through one or more strut assemblies, said tailgate panel is provided with one or more retaining means. 2. Sliding tailgate assembly as claimed in claim 1 wherein said tailgate panel is provided with one or more guide channels to facilitate sliding motion. 3. Sliding tailgate assembly as claimed in claims 1 and 2 wherein said strut assembly consists of a piston and cylinder arrangement, said cylinder is mounted inside the rear of vehicle and piston is slidably fitted inside the said cylinder, said piston have piston head and piston rod with the cross-section of the said piston head being greater than that of the said piston rod and the end of the said cylinder is provided with a flange to prevent separation of the said piston from said cylinder and a spring is provided on said piston rod with one end fitted rigidly to the said flange and the other end fitted on the said piston rod through another flange. 4. Sliding tailgate assembly as claimed in claims 1 to 3 wherein said strut assembly is provided with a roller at the end of said piston rod. 5. Sliding tailgate assembly as claimed in claims 1 to 4 wherein said roller is constrained within the said guide channel. 6. Sliding tailgate assembly as claimed in claims 1 to 4 wherein said retaining means is a torsion spring loaded retainer mounted inside a slot provided in the said guide channel. 8 7. Sliding tailgate assembly as claimed in claims 1 to 5 wherein said tailgate panel is provided with one or more pegs at the bottom face. 8. Vehicle fitted with a sliding tailgate assembly as claimed in claims 1 to 7. 9. Sliding tailgate assembly for vehicle substantially as herein described with reference to the accompanying drawings. 9 ABSTRACT “SLIDING TAILGATE ASSEMBLY FOR VEHICLE” The present invention relates to the opening and closing mechanism of tailgates and more particularly to a sliding type tailgate for vehicles in which direct sliding up of the tailgate is not possible due to the design of the vehicle e.g. vehicles in which tailgates which arc not integral with the rear windscreen. The sliding tailgate assembly consists of a tailgate panel, a pair of guide channels provided on the tailgate panel, a lock unit with one part provided on the tailgate panel and another part on the vehicle rear, a pair of spring loaded struts fixed to the vehicle rear, a pair of rollers mounted at the end of each strut, at least two torsion spring loaded retainers on the tailgate within the guide channels, and a peg at the centre of the bottom face of the tailgate panel and a corresponding cavity is provided on the vehicle body to accommodate the said peg during normal closed position. In the closed position of the tailgate, the spring loaded struts are in a compressed state and the tailgate lock is engaged. When the tailgate lock is unlocked and the lock lever is pulled, the tailgate pops out to a small distance in order to prevent the interference with the rear windscreen while sliding and the tailgate can then be lifted upwards. Fig 1 |
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586-MUM-2007-ABSTRACT(26-11-2010).pdf
586-MUM-2007-ABSTRACT(29-3-2007).pdf
586-MUM-2007-ABSTRACT(GRANTED)-(31-1-2012).pdf
586-MUM-2007-CANCELLED PAGES(8-8-2011).pdf
586-MUM-2007-CLAIMS(AMENDED)-(26-11-2010).pdf
586-MUM-2007-CLAIMS(AMENDED)-(8-8-2011).pdf
586-MUM-2007-CLAIMS(GRANTED)-(31-1-2012).pdf
586-mum-2007-correspondence(14-1-2008).pdf
586-MUM-2007-CORRESPONDENCE(30-11-2010).pdf
586-mum-2007-correspondence(ipo)-(27-11-2009).pdf
586-MUM-2007-CORRESPONDENCE(IPO)-(31-1-2012).pdf
586-mum-2007-correspondence-received.pdf
586-mum-2007-descripiton (complete).pdf
586-MUM-2007-DESCRIPTION(GRANTED)-(31-1-2012).pdf
586-MUM-2007-DRAIWNG(GRANTED)-(31-1-2012).pdf
586-MUM-2007-DRAWING(26-11-2010).pdf
586-MUM-2007-DRAWING(29-3-2007).pdf
586-MUM-2007-DRAWING(8-8-2011).pdf
586-MUM-2007-DRAWING(AMENDED)-(26-11-2010).pdf
586-mum-2007-form 1(11-1-2008).pdf
586-mum-2007-form 18(17-4-2007).pdf
586-MUM-2007-FORM 2(GRANTED)-(31-1-2012).pdf
586-MUM-2007-FORM 2(TITLE PAGE)-(COMPLETE)-(29-3-2007).pdf
586-MUM-2007-FORM 2(TITLE PAGE)-(GRANTED)-(31-1-2012).pdf
586-MUM-2007-FORM 3(26-11-2010).pdf
586-MUM-2007-FORM 8(30-11-2010).pdf
586-mum-2007-form 9(17-4-2007).pdf
586-MUM-2007-MARKED COPY(26-11-2010).pdf
586-MUM-2007-MARKED COPY(8-8-2011).pdf
586-mum-2007-petition under rule 137(14-1-2008).pdf
586-MUM-2007-REPLY TO EXAMINATION REPORT(26-11-2010).pdf
586-MUM-2007-REPLY TO HEARING(8-8-2011).pdf
586-MUM-2007-SPECIFICATION(AMENDED)-(26-11-2010).pdf
Patent Number | 250828 | |||||||||
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Indian Patent Application Number | 586/MUM/2007 | |||||||||
PG Journal Number | 05/2012 | |||||||||
Publication Date | 03-Feb-2012 | |||||||||
Grant Date | 31-Jan-2012 | |||||||||
Date of Filing | 29-Mar-2007 | |||||||||
Name of Patentee | TATA MOTAORS LIMITED | |||||||||
Applicant Address | BOMBAY HOUSE, 24 HOMI MODY STREET, HUTATMA CHOWK, MUMBAI 400 001 | |||||||||
Inventors:
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PCT International Classification Number | B60J5/12 | |||||||||
PCT International Application Number | N/A | |||||||||
PCT International Filing date | ||||||||||
PCT Conventions:
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