GB2184640A

GB2184640A - Ventilated safety helmet

Info

Publication number: GB2184640A
Application number: GB08529337A
Authority: GB
Inventors: Frank Gourley Thompson
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-11-28
Filing date: 1985-11-28
Publication date: 1987-07-01
Also published as: GB8529337D0

Abstract

The chin guard of a full-face visored motor cyclist's helmet is formed with an array of perforations (19) through which airflows to a plenum chamber (21) fixed to the inside surface of the chin guard. Tubular ducts (22) lead from the plenum chamber (21) to the base of the visor (12) so as to prevent misting over of the visor (12). <IMAGE>

Description

SPECIFICATION Ventilated safety helmet Fieldoftheinvention The invention relates to full-face safety helmets.

Afull4ace safety helmet is a helmet in which the helmet shell extends down around the wearer's ears and also extends forward to encasethewearers mouth and to form a chin guard.

Review ofart known to the appllcant Full-face safety helmets are worn by motorcyclists (amongst other potential users) and almost always incorporate a transparentvisor which, in use, covers the relatively small face opening ofthe helmet. The visor is usually unperforated. The helmet shell is usually extensively padded to fit tightly on the wearer's head. For these reasons, the visored helmet can become uncomfortably hot and also tends to mist up inside.

Forthese reasons it is common to see motor cyclists travelling with their visors partly orfully raised. This, however, can be dangerous. Few, if any, visors are designed to stay up properly when the motor cyclist is moving at speed. In such conditions the air pressure around the base ofthe raised visor can tend to pull the helmet offthe wearer's head and can generate unpleasant wind noise. More annoying still, and potentially more dangerous, isthatthere is nothing to stop insects and grit being carried into the motor cyclist's eyes when travelling with the visor partly orfully raised; and certain designs of visor in certain partly or fully raised positions can create air flows which positively encourage this.

Forthese reasons the conventional visored helmet is unsatisfactory. All the indications are, however, that modern motorcyclists in particularwill notgive upthefull-face type of helmet. There is thus a continuing problem two which the known art provides no solution.

Summary ofthe invention According to the invention a full-facevisored safety helmet has its chin guard perforated and incorporates means to duct air, entering the helmet through the perforations, to the base region ofthe inside face ofthe visor.

Such a helmet, in use, admits an airflow to the inside face of the visor which helps to keep the visor from misting over and to keep the wearer's face from becoming unduly hot. Because the air enters atthe base of the visor, rather than in line with the wearer's eyes, and provided of course thatthe perforations are kept suitably small, the risk of insects or grit entering the wearer's eyes is greatly reduced if not virtually eliminated.

Preferably, the perforations comprise an array of individually separate holes piercing the chin guard.

Thisminimisesthe riskofinsectsorgritenteringthe helmet when compared with the use of one volumetrically equivalent larger perforation.

Preferably also the perforations lead initially into a plenum chamber within the helmet, from which chamber a plurality of ducts leads to the base region of the inside face ofthe visor. The use of a plenum chamber in this way again reduces the risk of or insects being taken straight to the base of the visor through the ducts.

The ducts, including the chamber if a chamber is incorporated, may be constructed from components which are fixed to the inside ofthe helmet shell in the chin guard region and are then covered by the internal padding ofthe helmet.

However, as the internal padding of the helmet may well need to be cut away to surround the ducts (and the chamber is used) without unduly deforming the padding, it may alternatively be possible for the ducts (and chamber if used) to be cut into the padding and for the padding then to be fixed in place sufficiently to define the ducts (and optional chamber).

For ease of manufacture and also for a relatively pleasing appearance when the chin guard is viewed externally, the perforations may all be of identical shape and may be spaced from one another in a geometrically regular and/or symetrical pattern.

Such a pattern could form a diamond or a square or a circle envelope of perforations.

Alternatively, or additionally, the pattern of perforations could deliberately spell out some readily recognised trade mark such as the helmet manufacturer's name or the trade mark by which that particular helmet is known.

The perforations may be countersunk into the chin guard region ofthe helmetshellfrom inside the shell, ratherthan being simple parallel-walled through-bores. The incoming airfinding its way through these divergent perforations will then not be simply admitted with undiminished force (as it would be ifthe perforations were parallel-sided). Nor will it be positively accelerated (as it would be if the perforations converged in the direction of the incoming airflow) The effect could be to admit a full quantity of airto the wearer's face whilst diffusing the airflow considerably and hence promoting safety of use.

Briefdescription ofthe drawings The accompanying drawings show by way of example the best way currently known to the applicant of putting the invention into practice. In these drawings: Figure 1 shows a full-face helmet in side elevation and with its visor down; Figure 2, shows in sectioned side elevation the chin guard region ofthe helmet; and Figure 3, again enlarged like Figure 2,showsthe Figure 2 region of the helmet in sectioned perspective view.

Description of the preferred embodiment Afull-face helmetshell 11 has itsface opening covered, in use, by a transparent visor 12 which can be raised and lowered about pivots 13, one on each opposite side ofthe helmet. The helmet is a motor cyclist's safety helmet and is conventionally padded internally over virtually its entire surface. The helmet incorporates a chin harness whose details form no essential part of the invention.

With thevisordown, as Figure 2 illustrates, the base region ofthe visor rests against a plastics lip 14 which is continuous and lips the periphery of the helmetfaceopening. A similar lip 15 (Figure 3) is also continuous and lips the bottom periphery of the helmet.

Each ofthe lips 14 and 15 has a projection respectively 16, 17 which is co-extensive with the lip and which projects into the helmet. Foamed plastics padding 18 fits between the two projections 16 and 17 in the chin guard region ofthe helmetshell.

An array of perforations 19 in the chin guard allows air to enter a circular-cylindrical plenum chamber 21 fixed to the inside surface of the chin guard. Respective tubular ducts 22 lead from the plenum chamber 21 along the inside surface of the chin guard to the projection 16 of the base opening lip 14wheretheythen open into the helmet adjacent the inside face of the base region ofthe visor 12.

The padding 18 is suitably cut awayto accommodate the plenum chamber 21 and the array of ducts 22.

Claims

1. A full-face visored safety helmet having its chin guard perforated and which incorporates means to duct air, entering the helmet through the perforations, to the base region ofthe inside face of the visor.

2. Asafety helmetaccording to Claim 1,which has an array of individually separate perforations piercing the chin guard.

3. A safety helmet according to Claim 2, wherein the perforations lead initially into a plenum chamber, from which chamber a plurality of ducts leads to the base region ofthe inside face ofthe visor.

4. A safety helmet according to Claim 1 wherein the duct means are constructed from components fixed to the inside ofthe helmet shell in the chin guard region and are then covered by the internal padding ofthehelmet.

5. A safety helmet according to Claim 4, wherein the chin guard region is bounded by upperand iower lips between which the padding is fitted.

6. Amethodofpreventing mistingoverofthe visor of a full-face visored safety helmet, which comprises providing duct means fixed to the helmet shell in the chin guard region thereof and covered by the internal padding ofthe helmet, said duct means providing fortheflowofairfrom the chin guard region of the helrnettothe inside face ofthevisor.

7. A fuil-face visored safety helmet substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

8. A method of preventing misting over of the visor of a full4aced visored motor cyclist's helmet substantially as hereinbefore described with referencetoand as illustrated in the accompanying drawings.