IMPROVED PROTECTIVE HELMET OF THE MOVABLE SEGMENT TYPE

Abstract: A protective helmet (10) comprises a plurality of segments (11, 12, 13) that are interhinged in a manner movable between an expanded operating position and a collapsed non-operating position, and reciprocal restraining and locking means (26, 27, 28, 29) acting between tha said segments to maintain them in the said expanded operating position. With the said retaining and locking means there also cooperate guide means (22, 23, 24, 25) adapted positively to guide the said segments (11, 12, 13) so as assure a correct moving of the segments and a correct reciprocal engagement of the said retaining means.

Description: The present invention relates to a protective helmet of the type comprising a plurality of segments hinged one to another in a manner movable between an expanded operating position and a collapsed non-operating position. A helmet of this type is for example described in U.S. Patents 3,514,787 and 3,991,422 and in EP-A-0 150 876. When in the collapsed position the segments, which are of a generally arcuate shape with different radii, arrange themselves one overlying the next, so as to occupy a minimun space. Especially for drivers of motorcycles, this characteristics is an important one inasmuch as during stops on the road a single-piece helmet is always awkward to carry about and, otherwise, calls for means for anchoring it to the motorcycle so as to prevent theft. On the other hand, a helmet with retractably movable segments can be placed in the box-shaped luggage carrier featured on many motorcycles, or in a small rucksack or even in a small bag. However, the embodiment of a protective helmet of the type mentioned above requires the solution of the not simple technical problem regarding the stability of the segments in the expanded position and also regarding the system of articulation, since this must be easy to operate. The overall object of the present invention is to solve the aforesaid technical problems and, in order to do so, the invention embodies a protective helmet of the type comprising: a plurality of segments that are interhinged in a manner movable between an expanded operating position and a collapsed non-operating position, and reciprocal restraining and locking means acting between the said segments to maintain them in the said expanded operating position, with the said retaining and locking means also cooperating guide means adapted positively to guide the said segments so as assure a correct moving of the segments and a correct reciprocal engagement of the said retaining means characterised in that said guide means consist of a series of cams and cam followers formed respectively on adjacent faces of the segments, and said locking means consists of ribs and complementary notches formed respectively on the inner and outer faces of the said segments. The structural and functional characteristics of the invention and its advantages will become more apparent from an examination of the following description, referred to the appended drawings which show an example of a helmet embodied according to the innovative principles of the invention. In the drawings: Figure 1 is a lateral elevation illustrating the said helmet in the expanded position; Figure 2 is a sectional view of the helmet of Figure 1; Figure 3 is a sectional view illustrating the helmet in the collapsed position; Figure 4 is a cross-sectional view taken on the line IV-IV of Figure 3; Figure 5 is a sectional view taken on the line V-V of Figure 2; Figure 6, 7 and 8 respectively show the three segments constituting the helmet; and Figure 9 is a detail of the system for expanding the segments. With reference to the drawings, the helmet in question is indicated overall by 10 and consists structurally of a plurality of segments, generally arc-shaped, which are hinged one to another so that they are able to dispose themselves in one of the two positions of expansion or collapse show in Figures 1 and 3 respectively. In the example shown, the helmet 10 comprises a central segment 11 and two terminal segments 12, 13, respectively front and rear. The segments 11, 12 and 13 are hinged one to another in the region of their opposite sides by the agency of two sets of cams, indicated overall by 14 and each able to be actuated by means of its own moving and locking knob 15 (Figure 4 and 8). Each set of cams comprises three discs 16, 17 and 18 mounted rotatably within complementary seats formed respectively in the segments 11, 12 and 13. Solid with the disc 18 there is a pin 19 which passes through eccentric holes of the discs 16 and 17 and projects outside the helmet as a terminal head 20 to which there is pivoted, at 21, the locking knob 15. The diameter and eccentricity of the discs 16, 17 and 18 are calculated so that the segments 11, 12 and 13 are caused reciprocally to approach each other and to move apart from each other as a result of rotation of the sets of cams 14 (the moved-apart position of the segments being indicated by a dashed-and-dotted line also in Figure 1), so as to permit the said segments to be interleaved one with another (in the collapsed position of Figure 3) or to be in the expanded position of Figure 1 in which the said segments are disposed in an essentially coplanar approached position, so as to form a hemispherical configuration. In accordance with the invention, the translation of the segments 11, 12 and 13 between the positions shown in Figures 1 and 3 is positively guided, on each side, by a pair of cam guides 22, 23 which act on respective cam followers in the form of pegs 24, 25. As Figure 4, 5, 6 and 8 of the drawings clearly show, the guides 22, 23 are respectively formed on the opposite inner faces of the segments 12, 13, while the pegs 24, 25 project from the opposite faces of the central segment 11. In this way the segments 11, 12 and 13, especially in the helmet-expanding phase (which is actuated by rotation in one direction of both sets of cams 14 by means of knobs 15) are positively guides so as to cause pairs of ribs 26 and 27, formed respectively on the opposite inner faces of the segments 11, 12, to engage complementary notches 28, 29 formed respectively on the outer faces of the segments 11, 13. The guides 22, 23 and respective pegs 24, 25 also act as limit switches and positively form the reciprocal angular position between the moved-apart and expanded segments (indicated by dots-and-dashes in Figure 1) and guide the radial approach movement determined by the rotation of the sets of cams 14. In this way the segments approach each other in a correct reciprocal angular position with no need for the user to maintain them in such position manually; for it would be problematical to bring about this position manually and also move the cams sets 14 by hand at the same time. The guided radial mutual approach movement of the segments as mentioned above also permits a sure and ready reciprocal mating of restraining means, shown in the form of ribs 26, 27 and complementary notches 28, 29, which ensure that the espanded 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 Figures 1 and 2. As will be clear, the locking of the segments in the aforesaid expanded position is actuated by moving the knobs 15 from the position of Figure 9 to the position of Figure 5, in which the toggle 30 exerts an action of reciprocal moving together (approach), and thus of stable clamping between the said segments 11, 12 and 13. In cooperation with the pegs 24, 25, the guides 22, 23 assure the correct disengagement of the ribs 26, 27 from the notches 28, 29 in the phase of collapsing the helmet into the position shown in Figure 3, such phase being actuated by rotation of the cam sets 14 in the direction opposite to the previous one. The object mentioned in the introductory part of the description is thus achieved.

Claims: Protective helmet of the type comprising a plurality of segments that are interhinged in a manner movable between an expanded operating position and a collapsed non-operating position, and reciprocal restaining and locking means acting between the said segments to maintain them in the said expanded operating position, with the said retaining and locking means also cooperating guide means adapted positively to guide the said segments so as assure a correct moving of the segments and a correct reciprocal engagement of the said retaining means characterised in that said guide means consist of a series of cams and cam followers formed respectively on adjacent faces of the segments, and said locking means consists of ribs and complementary notches formed respectively on the inner and outer faces of the said segments. Helmet as described in claim 1, wherein the said segments are interhinged, in the region of opposed sides, by means of two sets of cams each comprising a plurality of discs rotatably mounted within complementary seats formed in the said segments, there being solid with the innermost disc a pin which passes through eccentric holes of the other discs to project outside the helmet as a head to which is pivoted a knob for moving and locking purpose. Helmet as described in claim 1), wherein the said segments are three in number: one intermediate, one anterior and one posterior.

Inventors: VILLA, PAOLO
Applicants: SMI S.A.
Application year: 1987
Main classification: A42B3
IPC codes: A63B71, A42B1, A42B3