SPECIFICATIONProtective helmet for driversThe invention relates to protective helmets particularly for use by drivers of motor vehicles, the helmets comprising a strong outer helmet shell which has a visor opening and to which a visor of transparent material is pivoted on both sides of the visor opening to swing over the visor opening.
The invention is based on the problem of providing a protective helmet of this kind with an antidazzle means which is adjustable in its anti-dazzle effect according to particular circumstances and requirements, and which does not require any modifications to the helmet shell for fitting the anti-dazzle means to the helmet, so that already existing helmets can be subsequently readily provided with the anti-dazzle means,According to the invention, a protective helmet comprises an outer helmet shell which has a visor opening and to which a visor of transparent material, which is pivotal over the visor opening, is mounted on both sides of the visor opening, and a protective screen member of transparent tinted material provided externally over the visor and arranged so that when the visor is pivoted into a position in front of the visor opening, the protective screen member, independently of the visor, can be pivoted between a lower position in which it covers at least the upper part of the visor opening and an upper position in which it is clear of the visor opening, the protective screen member being mounted either jointly with the visor on a common pivot axis on the helmet shell or being mounted on a pivot axis on the visor which is separate from the axis of the visor.
If the helmet is one in which nut members that are resistant to compression and tensile stresses and are non-rotatable are let into the helmet shell for connecting the visor, a preferred embodiment of the invention is characterised in that a mounting plate is secured with an interposed mounting trunnion nonrotatably relatively to each nut member and the visor and the protective screen member have openings fitted on the mounting trunnions, the protective screen member being resiliently deformed and by virtue of such deformation clamped with frictional restraint between the visor and the mounting plate.
The mounting plate may advantageously have abutment projections which are directed towards the shell of the helmet and which project into openings which extend in the visor and in the protective screen member over the respective angle of pivotal movement thereof in order to limit the pivotal movement.
If on the other hand the protective screen member is mounted on the visor with its pivot axis remote from that of the visor, the arrangement is preferably such that mounting trunnions which define the pivot axis for the protective screen member are provided on the visor, with the protective screen member being carried by means of mounting openings on the mounting trunnions, and that a plate between which and the visor the protective screen member is clamped is provided on each mounting trunnion.
The mounting trunnions may be formed by screws.
Moreover, it is desirable for the plate to have two projections which are directed substantially perpendicularto each other and which are bent to lie against the visor beyond an area around the trunnions and which are so secured to the visor that the plate is non-rotatable relatively to the visor. A pressure member which urges the mounting disc towards the visor is provided on the mounting trunnion. This arrangement provides that, although the protective screen member is gripped between the and the plate and is therefore held in its selected pivotal position by the frictional restraint which is produced by the gripping action, the plate is also pre-stressed against the pressure member and therefore does not lie against the visor if the protective screen member is removed from between the visor and the plate.This makes it possible, as is highly advantageous, for the mounting openings in the protective screen member to be shaped so as to open into slots extending towards the edge of the protective screen member, each slot being initially narrower in width than the diameter of the associated mounting opening and increasing in width towards the edge of the protective screen member.
Thus, after final assembly of the mounting trunnion, the plate and the pressure member, the protective screen member only needs to be inserted into the space between the visor and the plate and pushed so that the slots travel over the mounting trunnions until, after passing the narrowest position in the slots, the mounting trunnions latch into the mounting openings. As a result, the protective screen member can be readily replaced.
The advance achieved by the invention is substantially that the protective helmet according to the invention is provided with a light-attenuating protective screen member which is adjustable independently of the visor and which can be set into and retained in its selected position by frictional forces, as required. In addition, another important factor is that the protective screen member can be mounted on the helmet without alterations to the helmet shell.
Even existing helmets can be readily subsequently fitted with the protective screen member. This can be effected alternatively either by the protective screen member being mounted jointly with the visor on the helmet shell or by the visor being replaced by a structure which has a protective screen member already mounted on the visor. Obviously, however, it is also possible to retain an existing visor and in this case simply to provide the visor with two holes for receiving the mounting trunnions which are required for fixing the protective screen member.
In orderthatthe invention may be clearly understood and readily carried into effect, protective helmets in accordance therewith will now be described, by way of example, with reference to the accompanying drawings, in which:Figure 1 shows a side view of a protective helmet, with a visor and a protective screen member each lowered to a lowermost pivotal position;Figure 2 shows a front view of the helmet of Figure 1;Figure 3 shows an exploded view of a fixing for the protective screen member on the helmet of Figures 1 and 2;Figure 4 shows a side view of a nut member forming part of the helmet of Figures 1 to 3;Figure 5shows a side view of a modification of the helmet of Figures 1 to 4;Figure 6 shows a front view of the helmet of Figure 5;Figure 7shows a section taken along line VII-VII inFigure 5; andFigure 8 shows a section taken along line IIX-IIX inFigure 7.
In the protective helmet for vehicle drivers shown in Figures 1 to 4, a strong outer helmet shell is denoted generally by reference numeral 1. The helmet is in the form of a so-called integral helmet, which means that the helmet is provided with a front chin portion 1.1. Between the chin portion 1.1 and the forehead portion 1.2 the shell 1 is provided with a visor opening 2. A visor 3 of transparent clear material is mounted on the helmet shell 1 on both sides of the visor opening 2. The visor 3 can be pivoted over the visor opening 2 to close the visor opening. Hinges 4 on which the visor 3 is mounted are located approximately in the temple regions of the helmet. The visor 3 can be fixed relatively to the helmet shell 1 by press stud connections 6, as shown in Figures 1 and 2 in which the visor covers the visor opening 2.A protective screen member 5 of transparent tinted material is provided externally over the visor 3. When the visor 3 is in its effective position in front of the visor opening 2, the protective screen member 5 can be pivoted, independently of the visor, between a lower position in which it covers at least the upper part of the visor opening 2 and an upper position in which the visor opening 2 is free.
Figure 1 shows the lower position in solid lines, and the upper position in broken lines. More particularly, as shown in Figures 1 to 4, the protective screen member 5 is mounted jointly with the visor 3 by common hinges 4 on the shell 1. Alternatively as shown in Figures 5 to 8, the protective screen member can be mounted on the visor 3 with its own hinges 4'.
Nut members 7 are let into the helmet shell 1 so as to be capable of resisting compression and tensile stresses and so as to be non-rotatable, for mounting the visor 3. In the embodiment shown in Figures 1 to 4, mounting plates 8 with interposed mounting trunnions are secured by screws 9 to the nut members 7. The screw connections are nonrotatable, for which purpose face protections 11 are provided on the mounting trunnions and engage in radial slots 12 in the nut members 7. The visor 3 and the protective screen member 5 are mounted on the mounting trunnions, by way of respective openings 13 and 14.The visor 3 and the protective screen member 5 are subjected to resilient deformation by bending to conform to the shape of the helmet and, as a result of the bending stresses which are thereby produced, are clamped with frictional restraint between the helmet shell 1 and the mounting plates 8.
The frictional restraint can be readily overcome when the protective screen member 5 is pivoted by hand, but the frictional restraint is sufficient to retain the protective screen member 5 in its selected position so that there is no need for special locking means. Moreover, the mounting plates 8 have projections 15 which are directed towards the helmet shell 1 and which project into arcuate openings 16 in the visor 3 and in the protective screen member 5 over the respective angles of pivotal movement thereof, for limiting the pivotal movement.
In the embodiment shown in Figures 5 to 8, mounting trunnions 17 are provided on the visor 3, to provide the hinges 4' for the protective screen member 5. The protective screen member 5 has openings 18 that engage the mounting trunnions 17.
On each mounting trunnion 17 is provided a plate 19, secured so that protective screen member 5 is frictionally clamped between the plate 19 and the visor 3. Thus, in this case also the protective screen member 5 can be adjusted against frictional restraint but is frictionally held in its adjusted position. Each plate 19 has two integral projections 20 which are directed substantially perpendicularly to each other.
The projections 20 bear against the visor 3 beyond an area around the trunnions and are secured to the visor beyond bent portions 21 of the projections in such a way that the plate 19 is non-rotatable relatively to the visor 3. In the embodiment illustrated, this is achieved by the projections 20 being bent around the edge of the visor 3, as indicated at 22. Moreover, a pressure member 23 which presses the plate 19 towards the visor 3 is provided on the mounting trunnion 17. In the embodiment illustrated, each mounting trunnion 17 is formed by a countersunk head screw which is let into the visor 3 and the pressure member 23 is a nut which is screwed onto this screw.The mounting openings 18 (Figure 8) of the protective screen member 5 open towards the edge of the protective screen member in the form of a slot 24 which initially, at the mounting opening 18, is of smaller width than the diameter of the opening, but which increases in width towards the edge of the protective screen member 5, at least to the diameter ofthe mounting opening 18. Therefore, the protective screen member 5 can be pushed by way of the slots 24 over the mounting trunnions 17 until, after passing the narrowest points in the slots, the mounting trunnions 17 latch into the mounting openings 18. Conversely, the protective screen member 5 can be pulled off the mounting trunnions 17 while the mounting trunnions 17 come out of the openings 18 through the slots 24. The protective screen member 5 can therefore be replaced without the necessity to release the counter- sunk head screws which form the mounting trunnions 17 and the plates 19 with their projections 20, from their respective positions. Even when the protective screen member 5 has been removed from the mounting trunnions 17, the plates 19 do not lie against the visor 3 as the plates 19, held on its projections 20, press resiliently against their respective pressure members 23. The space between the visor 3 and each plate 19 therefore remains open so that the protective screen member can be readly inserted between the visor 3 and the plate 19 and can be fitted by engaging the slot 24 and the mounting opening 18 over the mounting trunnion 17.