Protective helmet with strap set and buckle

Abstract: The disclosure relates to a strap set for a protective helmet and a buckle therefor. The strap set consists of a rear strap (3) which is secured in the rear portion of the helmet, a front strap (2) which is secured in the front portion of the helmet, and a chinstrap (4). The three straps are united by a buckle (5) which may be displaced along that strap which is constituted by the front strap (2) and the chinstrap. The front strap and the chinstrap (4) are led through a guide and lead device (8) on a rotary portion (7) of the buckle (5), and the rear strap (3) is adjustably secured in the body (9) of the buckle (5). The body (9) is an approximately oblong plate which has a circular aperture (13) where the rotary portion (7) is located. In its turn, the rotary portion (7) has two slits (19, 20) such that a boom (23) is formed. The front strap (2)/the chinstrap (4) is passed around the boom (23).

Description: TECHNICAL FIELD The present invention relates to a protective helmet, eg a bicycle helmet, comprising a strap set having straps on either side of the helmet , namely a first strap constituting a front strap which is secured in a front side portion of the helmet; a second strap constituting a rear strap which is secured in a rear side portion or a neck portion of the helmet, the opposite end of said rear strap being connected to a buckle , said first strap extending through a guide or lead device in the buckle by means of which the buckle is adjustable along the first strap, said first strap also constituting a chinstrap extending from the buckle and having a locking member for fixedly locking the chinstrap in a corresponding locking member in a chinstrap from the opposite side of the helmet. BACKGROUND ART Protective helmets for cyclists are known in numerous different versions and have various types of strap sets and buckles included therein. One design and construction which is common on the market has a rear strap, a neck strap, manufactured in one piece with a front strap which is secured in the front side portion of the helmet. In the central region of this rear/front strap, there is disposed a buckle with two obliquely inclined slits through which the front and rear parts of the strap run, the longitudinal direction of the slits being approximately at right angles to the longitudinal directions of the strap parts. In a lower region of the buckle, the strap extends through a further slit from one side of the buckle to the other, so that hereby the strap will be folded double in the region of the buckle, with one strap portion substantially on each side thereof. The prior art helmet's strap set further has a chinstrap which is secured in the above-mentioned buckle. The prior art design and construction may function under certain conditions but suffers from considerable drawbacks, principally in that the strap is folded in a manner other than in accordance with the requirements dictated by the geometry of the buckle. This involves unaesthetic creases and also oblique loadings in the strap. Further, the adjustment possibilities of the strap set are very poor, in that only the position of the buckle along the combined neck strap/front strap can be varied. There is no possibility of varying the length of the neck strap. US 5 272 773 discloses a helmet according to the preamble of present claim 1 having a similar strap set. Thus this patent discloses a helmet which consists of a hood which includes a shock-absorbing inner portion , an outer shell, inner cushions, and also straps at the temples and from the neck of the wearer of the helmet, respectively. The straps are secured in three points in the inside of the outer shell. The straps from the neck and the straps from the wearer's temples are united on each side of the helmet in adjustment plates. The front strap is through-going and continues downwards in order to be tightened around the chin of the wearer. This helmet has the same drawbacks as the one described above. GB 2 303 168 discloses a helmet, for example, a bicycle helmet with an adjustable and lockable strap set having a strap divider which is intended to be employed on, for example, bicycle helmets. The straps form, on each side of the helmet, a Y-shaped arrangement. The strap divider has a rotary element with a knob. On tightening, the rotary element presses the straps against one another and against the rear wall of a body portion. In one embodiment, the rotary element is connected to the body portion by means of threads, but other embodiments also occur as regards realising the clamping action between the element and the body portion. Although this strap divider offers a good adjustment range to the strap there is still a risk that the strap be wrinkled or obliquely loaded. PROBLEM STRUCTURE The present invention has for its object to design the strap set disclosed by way of introduction such that it will be easy to adapt to each individual wearer and thereafter will be self-adjusting to a certain degree. The present invention also has for its object to design the strap set such that it may be manufactured simply and economically and that it will be both functionally reliable and aesthetically attractive. SOLUTION The objects forming the basis of the present invention will be attained of the protective helmet is designed as described in the characterizing part of claim 1. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS The present invention will now be described in greater detail hereinbelow, with reference to the accompanying Drawings. In the accompanying Drawings: Fig. 1 shows a bicycle helmet from the side, fitted with the strap set according to the present invention; Fig. 2 shows a buckle included in the strap set, seen from the outside, i.e. from that side facing away from the head of the helmet wearer; Fig. 3 shows the buckle according to Fig. 2, seen from the inside; and Fig. 4 is a perspective view of a rotary portion included in the buckle according to Figs. 2 and 3. DESCRIPTION OF PREFERRED EMBODIMENT In Fig. 1, which shows a protective helmet, for example a bicycle helmet, straight from the side, reference numeral 1 relates to a helmet shell included in the helmet, reference numeral 2 relates to a first strap constituting a front strap and reference numeral 3 to a second strap constituting a rear strap, a neckstrap, and reference numeral 4 relates to a chinstrap, also constituted in said first strap for the helmet. The first strap extends through a buckle 5. The upper/front end of the front strap 2 is secured in a front side portion of the helmet shell 1, while the rear/upper end portion of the rear strap 3 is correspondingly secured in a rear side portion of the helmet shell 1, or possibly in the neck portion of the helmet. The exact appearance of the anchorage of the front and rear straps in the helmet shell constitutes no germane part of the present invention. Given that the front strap 2 and the chinstrap 4 are through-going through the buckle 5, this may be displaced along the longitudinal direction of the front strap /chinstrap. By adapting the slip resistance between the buckle 5 and straps by employing a friction device, the strap set may be largely made self-adjusting when the helmet is put on, at the same time as a pre-set adjustment is retained. The rear strap 3 is secured in a rear end of the buckle 5 which has the approximate configuration of a slightly elongate plate. The rear strap 3 is secured by means of an anchorage device 6 which permits simple longitudinal adjustment of the strap 3 in the buckle. As a result, the length of the rear strap can be simply adjusted, at the same time as the position of the buckle 5 along the front strap / chinstrap may be readily adjusted, possibly be entirely self-adjusting when the helmet is put on. That described above in respect of the straps 2-4 as well as the helmet, the buckle 5 and its anchorage device 6 has its counterpart in an identical set of straps etc., on the opposite side of the helmet 1. If, in Fig. 1, the position of the buckle 5 is varied in the vertical direction, it will readily be perceived that the front strap 2 will be directed differently to that shown in the Figure. If, for example, the buckle is displaced greatly upwards, the front strap 2 will slope more markedly in relation to the horizontal plane. For such a change in the orientation of the strap not to cause fold-formation or oblique loading on the straps, the buckle includes a rotary portion 7 which supports the lead or guide device 8 through which the strap 2, 4 is passed. As was intimated above, the buckle 5 is approximately of the shape of a somewhat elongate plate with a plane of extent which, when the straps 2-4 hang freely as in Fig. 1, is approximately parallel with the plane which is defined by the straps 2-4. The axis of rotation of the rotary potion 7 is transversely directed, preferably at right angles, to the plane of extent of the buckle 5 and, thereby, also at right angles to the plane of the straps 2-4. Fig. 2 shows the buckle 5 seen from the same side as in Fig. 1, i.e. from the outside of the buckle and the strap set. The buckle has a body portion 9 which may be preferably of one piece manufacture from a suitable plastic material. The anchorage device 6 for the rear strap 3 is formed direct in the body portion 9 and includes two mutually approximately parallel slits 10 and 11 and a boom 12 extending therebetween. An adjustable anchorage device 6 according to this type is previously known and functions such that a free end portion of the rear strap from the inside of the buckle (the side facing away from the observer of Fig. 2) is passed through the slit 11, up over the boom 12 and back again through the slit 10. Suitably, the boom 12 may, along its side facing towards the slit 11, have a friction or engagement-increasing device in the form of a toothed or grooved portion or the like. Such devices are also previously known in the art. The body portion 9 has, in its end facing away from the anchorage device 6, a cylindrical aperture 13 in which the rotary portion 7 is rotatably secured. Approximately in the centre of the thickness direction of the body portion 9, the cylindrical aperture 13 has a rib 14 of square or rectangular cross section. The rib extends into the aperture and extends along its entire circumference. The rib 14 serves for securing the rotary portion 7. The rotary portion 7, which is shown in perspective in Fig. 4, has a substantially cylindrical peripheral surface 15 which is of such diameter that it may abut rotatably against the radial inner surface of the rib 14, which itself is also suitably cylindrical. In order to prevent the rotary portion 7 from falling through the aperture in the body portion 9, the rotary portion has, on its outside (facing towards the observer of Fig. 2), a radially projecting, circumferential flange 16. When the rotary portion 7 is mounted in the aperture 13, the flange 16 rests on the flank surface-of the rib 14. Hereby, the rotary portion 7 is prevented from being displaced from the outside of the buckle through the aperture to the inside of the buckle. It should be noted that, when the buckle is used, the major loadings on the rotary portion will lie in this direction, i.e. from the outside towards the inside. In order to retain the rotary portion 7 in the aperture 13, the rotary portion has, on its inside, at least two but possibly more radially projecting heels 17 which may be snapped into the inside of the rib 14. In order to permit such snap-action, the heels 17 are provided, on their inside, with conical ramp surfaces 18 which strive to press both of the heels in towards the centre of the rotary portion when the rotary portion is axially pressed into the aperture. The rotary portion 7 has two mutually approximately parallel grooves 19 and 20 which have open ends 21 and 22, respectively. On inward pressing of the diametrically opposed heels 17, these may spring in radially through deformations in the material in the region of the closed ends of the grooves 19 and 20. The grooves 19 and 20 form between them an elongate boom 23 whose detailed design will be described more closely below. The grooves 19 and 20 and the boom 23 serve the purpose of lead or guide device 8 for leading or guiding the straps 2, 4. In such instance, the strap 2 enters in on the rear side of the buckle 5, extends through the groove 20 to the outside of the boom 23, along its elongate outside 24 and back in through the second groove 19. By a suitable formation of the defining surfaces of the grooves 19 and 20, the formation and possible surface structure of the outside 24 of the boom 23, and in particular the corner regions between the boom and the two slits, the boom and the slits may together be given the function of friction device which controls the resistance exercised when the buckle is displaced along the strap 2, 4. It will be apparent from Fig. 4 that the boom 23 has an elongate, outer surface 24 against which abuts the inside of the strap 2, 4. This elongate surface is located at the closed ends of the grooves 19 and 20, flush with the outer surface 25 of the rotary portion 7. The opposite end of the elongate surface 24 is located a distance in behind the outer surface 25 of the rotary portion, and suitably somewhat in the region of the rear side of the rotary portion 7. As a result, the transition region between the straps 2 and 4 will be inclined in relation to the plane of extent of the buckle 5 such that the edge portion of the strap 2, 4 facing towards the rear strap 3 is located inside the outer surface 25 of the rotary portion. As a result, there will be achieved a further reduction of the risk of fold-formation and oblique loadings on the straps when the chinstrap 4 is angled in obliquely forwards under the chin of the helmet wearer. The present invention may be modified without departing from the scope of the appended Claims.

Claims: A protective helmet, eg a bicycle helmet, comprising a strap set having straps on either side of the helmet (1), namely a first strap constituting a front strap (2) which is secured in a front side portion of the helmet; a second strap constituting a rear strap (3) which is secured in a rear side portion or a neck portion of the helmet, the opposite end of said rear strap being connected to a buckle (5), said first strap extending through a guide or lead device (8) in the buckle by means of which the buckle is adjustable along the first strap, said first strap also constituting a chinstrap (4) extending from the buckle and having a locking member for fixedly locking the chinstrap in a corresponding locking member in a chinstrap from the opposite side of the helmet, characterized in that the guide or lead device (8) is rotatably provided in the buckle (5) about an axis that is substantially normal to a plane defined by the front strap (2), the rear strap (3) and the chinstrap (4) when the straps are hanging freely. Protective helmet as claimed in claim 1, characterized in that the buckle (5) is plate shaped with its plane of extent approximately with the plane of the straps (2, 3, 4). Protective helmet as claimed in claim 1 or 2, characterized in that the guide or lead device (8) is disposed on a separate part (7), which is rotary in relation to the rest of the buckle (5). Protective helmet as claimed in claim 3, characterized in that the buckle (5) has a body portion (9) of the approximate configuration of a slightly elongate plate, in whose one end portion a circular aperture (13) is provided; and that the rotary portion (7) has the approximate configuration of a circular plate which is rotatably secured in the aperture, the axis of rotation of the rotary portion (7) being transversely directed in relation to the plane of extent of the body portion (9). Protective helmet as claimed in any of claims 3 or 4, characterized in that the rotary portion (7) has two grooves (19, 20, respectively) which are open at their one end (21, 22) and between which an approximately diametrically directed boom (23) is formed, the first strap (2, 4) being passable from the one side of the rotary portion (7), through one (20) of the grooves, around the boom (23) and back via the other (19) of the grooves. Protective helmet as claimed in claim 5, characterized in that the elongate surface (24) of the boom (12) intended for abutment against the first strap (2, 4) is located with its one end at one side of the rotary portion (7), while the elongate surface (24) is located with its opposite end at the opposite side of the rotary portion.

Inventors: GUSTAVSSON PETER, GUSTAVSSON, PETER
Applicants: STARFLEX AB
Application year: 1998
Main classification: A42B3
IPC codes: A42B3, A44B11