3. PREAMBLE TO THE DESCRIPTION

a. Background:

Against the background of safety, the consciousness is important criteria for riders. People are cautioned to wear helmets in order to reduce the impact on head. Even though helmets are satisfying primary safety features the prime drawback of helmets are bulky and takes more space. The main objective of the foldable helmet is to develop a comfortable, self adjusting compact helmet and to reduce the overall dimensions with weight. The present invention relates to a Motorcycle helmets, in particular for motorcycles riders, it is difficult to carry due to bulky in nature and also there are chances of helmet theft with the present locking system. To overcome the said problem, the foldable helmet has been developed.

b. Description of Related Art:
The helmet of the similar type described in U.S Patent no. 3514787, 3991422, 4827537 are only suitable in the field of construction works and bicycle riding. In these helmets there is no protection for lower Jaw, there is no interlocking between the plates and also the plate side locking system is complicated. Here the developed foldable motorcycle helmet is used for motorcycle riding and it has extra protection on the lower jaw from sudden impact.

c. Summary of invention:

The objective of the present invention is to design protective helmet and also to reduce the size of the helmet. Foldable helmet consists of five plates of different radius which are pivoted at a point, each plate slides one upon the other about the pivot at specified angles and gains the shape of the helmet. Each plate is interlocked with respective adjacent plates by moving with certain degree of rotation. Self interlocking of extreme plates has been made with locking hocks. Finally all the plates are locked using lock plates on either side.

PROVISIONAL COMPLETE
The following specification describes The following specification particularly describes the invention invention and the manner in which it is to be performed

4. DESCRIPTION

BRIEF DESCRIPTION OF THE DRAWING
Other features and advantages of the present invention will be appreciated, as well as methods of operation and the function of the related parts, from a study of the following detailed description, the appended claims, and the drawings, all of which form a part of this application. In the drawings:

FIG. 1 is a cross-sectional side view of the helmet in the expanded position.

FIG. 2 is a cross-sectional side view of the helmet in the folded position.

FIG. 3 is a detail of the lock plate for locking the segments.

FIG. 4 is a Pictorial cross-sectional view illustrating the said helmet in the expanded position.

FIG. 5 is a schematic perspective view of the helmet in accordance with the invention in its operational configuration in the folded position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings, the helmet in question is indicated overall by 22 and consists structurally of a plurality of plates which are dragged one inside the other so that they are able to dispose themselves or collapse in FIGS. 2.

In the examples shown, the helmet 22 comprises a central plate 3, four terminal plates 4, 5, 2 and 1 respectively front and rear.

The plates 1, 2, 3, 4 and 5 are dragged one over other in the region of their opposite sides by the agency of a set of lock plates having pins indicated overall in FIG. 3 by 8, 9, 10, 11 and 12 which are able to be actuated by means of its own moving and locking knob 6 and 7 which are indicated in FIG. 1.

Each lock plates consists of five pins 8, 9, 10, 11, and 12 mounted radially, where each pin passes to the respective holes of corresponding plates. FIG. 4, shows respectively all the plates and the lock plates which are pivoted.

In accordance with the invention, the translation of the plates 1, 2, 3,4, and 5 between the positions shown in FIG. 4 are positively guided and the lock plate pins 8, 9, 10, 11 and 12 (FIG. 3) are inserted in to the corresponding holes of the plates.

Self locking is provided between the two plates 1 and 5 by hook 19 shown in FIGS. 4 and 5 respectively. When the helmet is expanded the hook 19 (FIG. 4) is engaged. Each plate is interlocked with respective adjacent plates by moving to certain degree of rotation. Self interlocking of extreme plates has been made with locking hooks.

As show in the FIG. 1 and 4, The fixed inner plate 1 of least radius of 130mm from the pivot axis and thickness of 6mm This plate covers the rear of the portion head. This plate has effective cushioning facility in comparison with all other plates. It provides housing for all other plates during folding.

From the plate 2, as shown in the FIG. 1 and 4, The adjacent to plate 1 of increasing radius of 138mm and thickness of 6mm which slides upon plate 1 about 48 degree during folding. This plate main function is to protect from rear impact.

From the plate 3, as shown in the FIG. 1 and 4, This plate having radius of 149mm and thickness of 9mm in which 6mm is plate and 3mm is rubber material for cushioning. This plate is considered as an important plate among all the plates this plate is located at the top portion of head for this purpose we provide a rubber material. In addition to sponge cushioning rubber cushioning provides still more extra cushioning effect.

From the plate 4, as shown in the FIG. 1 and 4, It is having a radius of 157mm and thickness of 6nim this plate is provided with a movable fiber glass with up and down motion. This glass can be lowered as per user's requirement. The main aim of providing this glass is to prevent the entering of dust to the eye's of user during riding and also to prevent injuries on face during crash.

From the plate 5, as shown in the FIG. 1 and 4, This is the final plate having radius of 168nmi and thickness of 8mm in which 6mm is plate thickness and 2mm is rubber layer on plate. This plate is provided with ventilation facility for breathing of the user.

The side two lock plates are provided as shown in FIG. 3, This lock plate is fixed on pivot on either side having the facility of moving inward and outward about the same pivot. This lock plate is in the form of steps it prevents the backward movement of plates.

The lock is Locking between 1 and 5 as shown in FIG. 4, it is provided because to avoid the backward movement of individual plates after helmet is opened. The Lock is spring actuated and fixed in plate and going to lock in plate during dragging the plates.

As shown in the FIG. 4, The cross-sectional view of helmet shows the locking systems. Initially each plates slides upon each other and locks together by projection of 20 degrees inclination on both sides. In between the contact edge of the plates the rubber is provided is to avoid the penetration of water, dust, and air.

In this way, Foldable helmet consists of 5 plates of different radius which are pivoted at common end point. Each plate slides one upon the other about the pivot at specified angles and gains the shape of helmet as shown in FIG. 4. Each plate is interlocking with respective adjacent plate after moving certain degree of rotation by self interlocking. Sliding of the plates can be achieved by connecting all the plates with the help of projections on the plates.

The expanded helmet is monolithic as is called for by the function of the expanded helmet which is to resist impacts, including violent impact. The helmet is in this manner kept positively locked in the expanded operating position shown in FIG. 1.

As will be clear, the locking of the plates in the aforesaid expanded position is actuated by moving lock plate 7 from the position of the FIG. 3. In which adjacent sides of the section are slightly spaced from each other, to the position of the FIG. 1 and also another locking hook 19 from the position of FIG. 4. Thus causes adjacent sides of the sections to engage each other and there by to produces a stable clamping between the said segments 1,2, 3,4 and 5.

In cooperation with lock plate pins 8, 9, 10, 11 and 12 and lock hook 19 guides the correct disengagement between segments in the phase of folding the helmet into the position shown in
FIG. 5.

5. CLAIMS (not applicable for provisional specification. Claims should start with the preamble - "I/We claim" on separate page)
I / We claim that -

1. FIG. 1, 4 and 5 shows the protective helmet of the type comprising a plurality of plates which are sliding one over other radial movement with common pivot 6, the two adjacent sections of lock plate 7 having pins which are firmly locked and also there is another lock hock 19 is placed in between plates, in the expanded position and in the folded non operating position lock plate and lock hock is disengaged where the plates slides one over the other with common pivot.

2. FIG. 4 shows the protective helmet as described in claim 1, locking between the plates 1,2,3,4 and 5 (20 and 21) with certain angle which avoids the disengagement between the plates.

3. FIG. 1 shows the protective helmet as described in claim 1, lock plate 7 with five pins 8, 9, 10, 11 and 12 is inserted into each hole of the plates with common pivot 6 when in expanded position.

4. FIG. 4 shows the protective helmet as described in claim 1, lock hock 19 is placed in between two extreme plates 1 and 5 when helmet is in expanded position.

5. FIG. 1 and 4 shows the protective helmet as described in claim 1, front side two plates 4 and 5 are provided for jaw protection and visibility.