GB2572195A - Improvements in headgear - Google Patents

Abstract

A bump cap 1 comprising a flexible outer fabric portion 2,3,4,5 that can cover the cranial, forehead and temporal regions of a user’s head; a rigid shell member (17, fig. 3a) mountable within the fabric portion, and covering at least the cranial and forehead regions; a resilient cushioning member (12, fig. 2) being mountable within the shell member and shaped to cover at least the cranial and forehead front region; an elongate connector joining two regions 9 of the fabric portion that has an adjustable length to draw the regions together; and a wheel ratchet 10. The joining regions 9 are preferably at a cut away portion of the fabric, and form pockets. Each end of the connector has an anchor with a flat enlarged region, which may be sewn into the pockets. The anchor is preferably triangular. The top region of the bump cap may comprise an air permeable mesh.

Description

IMPROVEMENTS IN HEADGEAR

Field of the Invention

The invention relates to bump caps, and particularly to the use of particular mechanisms to secure such caps to a user’s head. The invention also relates to methods of attaching such mechanisms to a bump cap.

Background and Prior Art

There are many circumstances in which it is desirable to protect a user’s head from injuries that might occur from impacts, the construction and manufacturing industries being prime examples. If there is a risk that a worker might be struck by a falling object, then the appropriate protection is an industrial safety helmet, often referred to as a hard hat. These tend to have a rigid shell that is held away from a user’s skull by a cradle and an arrangements is of straps that are able to absorb much of the impact force, thereby significantly reduces the forces transferred to a user’s head.

In other circumstances, e.g. where there is no risk of falling objects, but where a worker might be employed within e.g. a factory environment having head-height structures, the main hazard is the risk of the worker accidentally striking their head against a hard stationary object. Such accidents tend to cause injuries such laceration to a user’s skin and other superficial injuries. In these circumstances, workers often wear caps that incorporate a hard shell to reduce the risk of penetration or laceration injury. Rather than being held away from the skull by a force-absorbing cradle and strap arrangement, the shell sits directly on top of the users head, separated by a cushioning material located between the shell and the head. This form of protection is often referred to as a “bump cap”, and the type of protective headgear to which this disclosure is directed.

In other fields, such as providing head protection to cyclists, skateboarders etc., the headgear must be designed to protect a user’s head primarily from a fall that causes the head to impact with the ground.

Bump caps are distinct from other types of head protection such as industrial safety helmets and cycle helmets as they have very different functions, and hence very different technical features. For example, the design of bump caps in Europe is regulated by European Standard EN812. A recent version of the standard (EN812:2012) explains that, unlike industrial helmets, bump caps are intended only to protect the wearer from static objects (e.g. walking into low ceilings or hanging obstructions). As such, impact tests are carried out similar to those required for industrial helmets, but using a lower energy level: a 5kg flat striker is dropped onto the bump cap from a height of 250mm, with a maximum allowable transmitted force of 15kN. Impacts are carried out on the front and rear of the helmet, with a headform 5 tilted at 30° and 60° to reflect the nature of any impacts likely in use. In terms of protection against penetration injury, bump caps are intended to provide protection against sharp or pointed objects (such as comers or protruding elements of static objects), and so a penetration test is required. The test is based on a method similar to the shock absorption test as described above, in that a striker is dropped from a set height onto the helmet fitted to a fixed headform. io However, in this case, the striker is a pointed cone, and rather than measure the transmitted force, the assessment is based on whether the striker makes contact with the headform underneath the helmet. The penetration test in EN 812 is carried out at a lower energy (500g striker dropped from 500mm) than that specified in the standard for industrial helmets, as required by European Standard EN 397.

In order to meet the requirements of EN397, industrial helmets must have attachment points for a chin strap. Such a requirement is not needed for a bump cap, and so the absence of a chin strap, or attachment points for such a strap is one of the characteristics of bump caps. By contrast to bump caps, industrial safety helmets meeting EN397 have a significantly more 20 stringent requirement for impact/shock absorption. For example, when a 5kg hemispherical striker is dropped onto an industrial helmet from a height of lm, the force transmission must not exceed 5kN. Penetration testing is again more rigorous, in which a 3kg pointed conical striker being dropped onto a helmet from a height of lm must not penetrate the helmet.

Cycle helmet requirements are described in European Standard EN1078, and have impact resistant standards appropriate for their intended purpose. For example, flat and kerbstone anvils are used with an impact velocity of ca. 5.4ms’¹ and 4.6ms’¹ respectively are used. In each impact, the deceleration of the helmet must not exceed 25 Og (with g being then acceleration due to gravity). In a similar way to industrial safety helmets, cycle helmets such so also be provided with retention systems such as chin straps.

It is clear that there is a great difference in requirements between head protection systems such as industrial safety helmets, cycle helmets, and the bump caps that are the focus of this present invention.

In order to provide the required protection, bump caps need not only to be sufficiently strong to mitigate the effects of the impacts described above, but need to be comfortable to wear, and to remain in place while needed.

Bump caps tend to have a fabric covering, into which a hard shell and cushioning material is secured. As the caps are not usually specifically made to fit a particular user’s head, not least for reasons of cost, they are usually provided with a means to enable the cap to either be adjustable to the size of a user’s head, or to adjust automatically. The adjustment means typically pulls an otherwise open region of the fabric cover together to effect the adjustment.

In simple forms, the adjustment means might merely consist of a length of elastic stretched between two points of the covering of the cap, or running completely around the cap in a seam. Whilst this type of arrangement gives a certain degree of stability to the cap, in use, elastic has the tendency to become less elastic over time, and after many uses, and becomes is less effective at securing the cap to a user’s head.

In another arrangement, an elastic or even inelastic cord might be used, e.g. within a seam surrounding the cap, or between two points of the fabric cover of the cap. A toggle is provided to releasably grip the two ends of the cord, thereby allowing the length to be adjusted to hold the cap in position. Whilst this can prove a secure fitting for the cap, the arrangement typically requires the user to use both hands to make the adjustment - one to pull the cords, and one to activate/release the toggle mechanism. In addition, the arrangement leaves the ends of the cords dangling from the toggle mechanism, which not only can be distracting when they contact the back of a user’s neck, but also run the risk of being caught up in head-height structures around which the user is working, causing the cap to be pulled off the user’s head.

In other arrangements, fabric or webbing straps provided on the cap, usually at the back, can be provided by a closure such as two cooperating regions of hook and loop fastening, such as so that sold under the registered trade mark Velcro®. While this is relatively convenient to use, and can sometimes be adjusted with a single hand, if the hook and loop regions are carefully positioned, the fastening rapidly becomes ineffective as the hooks tend to accumulate fibrous detritus in use, especially in the often dirty environments in which the caps are destined to be used.

Since the more widespread use of injection-moulded plastics, other more sophisticated fasteners have also been used. Among these are “snap fittings” that comprise two, typically plastic, strips; one strip is provided with a series of linearly-spaced apart holes, and the other with a corresponding series of mushroom-profile protrusions that can be releasably engaged into the holes to provide an adjustable-length strap. These however, need two hands to adjust, and can usually only be adjusted when the cap is not being worn, requiring a process of trial5 and-error to find the correct length. In another form of closure, a flat strip of plastics material is provided having a series of recessed ratchet elements that engage with corresponding protruding ratchet elements on a second such strip. One of the strips is provided with loop structures to receive the end of the other strip, and hold the ratchet elements together. The flexibility of the plastic allows the two ends of the strips to be pushed together to tighten the 10 fastening. Again, this requires two hands to make the adjustment: either one hand to pull the end of one of the strips while the other hand holds the cap or other strap to prevent rotation of the cap on the user’s head, or by gripping the ends of each of the straps with a corresponding hand, and pushing the ends together. This arrangement is quite difficult to adjust correctly, and especially difficult to increase the length of the strap arrangement against the action of the is ratchet. As a result, there is a risk that the cap will be badly adjusted, and be either prone to falling off a user’s head, or too tight to be comfortable.

The issue of single-handed adjustment is really quite important in the context of bump caps: they are often worn for long periods of time, and might need to be tightened onto the head 20 during use should they become loose for any reason. If such tightening requires a two-handed operation, this cannot be accomplished while a user is performing other tasks, such driving a fork-lift truck. In the situation where a bump cap needs to be removed in order to tighten its fit, this causes an even more serious problem that the user has no head protection while the cap is being adjusted.

It is among the objects of the present invention to attempt a solution to these and other problems.

Summary of the Invention

Accordingly, the invention provides a bump cap comprising: (a) a flexible outer fabric portion so sized and shaped as to cover the cranial, forehead and temporal region of a user’s head; (b) a substantially rigid shell member so sized and shaped as to cover at least the cranial and forehead region of a user’s skull said shell member being mountable within said fabric portion; (c) a resilient cushioning member so sized and shaped as to cover at least the cranial and forehead front region of a user’s skull said cushioning member being mountable within said shell member; (d) an elongate adjustable length connector joining two spaced-apart joining regions of said fabric portion such that reducing the length of the connector acts to draw said regions together, thereby securing said cap on the head of a user; wherein said adjustment member comprises a wheel ratchet.

Preferably, said joining regions are located at each end of a cut-away portion of said fabric 5 portion.

In any embodiment it is preferred that each end of said connector is provided with an anchor comprising a substantially flat enlarged region and each joining region is provided with a pocket to receive and hold a corresponding anchor. More preferably, each anchor is sewn 10 within its corresponding pocket.

Where such an anchor is used, it is preferred that said anchor is triangular.

In any aspect of the invention it is also preferred that said connector is configured to he is against a user’s occipital bone.

Also in any aspect of the invention it is preferred that a top region of said portion comprises an air-permeable mesh.

Brief Description of the Figures

The invention will be described with reference to the accompanying figures in which:

Figure 1 illustrates a rear view of an embodiment of a bump cap of the invention;

Figure 2 illustrates an interior view of an embodiment of a bump cap of the invention;

Figures 3A-3B illustrate a known shell forming part of an embodiment of a bump cap of the 25 invention in plan, rear elevation and side elevation respectively;

Figures 4A-4B illustrate parts of a known wheel ratchet forming part of an embodiment of a bump cap of the invention;

Figure 5 illustrates a tensioning member and cog forming part of an embodiment of a preferred connector of the invention; and so Figure 6-10 illustrate embodiments of bump caps of the invention.

Description of Preferred Embodiments

Figure 1 illustrates a rear view of an embodiment of a bump cap of the invention, generally indicated by 1. The cap 1 comprises an outer fabric portion 2 that is shaped and sized to cover 35 the cranial, forehead and temporal region of a user’s skull. The lower perimeter of the fabric portion lies approximately in a plane defined by the orbit of the skull, and the point of attachment of a user’s ears to the scalp. In this embodiment, the cover comprises a series of sewn-together fabric panels, including a cranial panel 3 comprising an air-permeable mesh to facilitate cooling of a user’s head, side panels 4 covering a user’s temples and inset panels 5 joining the side panels 4 to the cranial panel 3. In this embodiment, a shaped perimeter 6 of the fabric portion defines a “cut-away” region to allow the cap to be adjusted in size to snugly 5 fit a user’s head. In this view, the lower face of an attached peak 7 and the interior face of the forehead region 8 of the fabric portion can also be seen.

Extending from the perimeter of the fabric portion are two joining panels 9 providing attachment regions 32 for each end of an elongate adjustable-length connector 10. The io connector 10 comprises a wheel ratchet, which will be described below. On the face of the connector 10 that abuts a user’s head or neck, padding 11 may be provided to provide comfort to a user, and help secure the cap in position on the user’s head.

In this embodiment, the joining panels 9 are formed of reflective material to provide better visibility of the cap in low light conditions.

The side panels 4 also define a pocket within which an impact resistant material, such as a sheet of closed-cell foam may be located to provide protection to the temple region of a user’s head.

Figure 2 illustrates a view of the interior of a bump cap 1 of the invention. Elements of the cap 1 previously described are indicated by the same reference numbers. Located inside the cap 1 is a resilient cushioning member 12 formed of a suitable material such as a closed cell foam. The cushioning member 12 is releasably affixed to a substantially rigid shell (not visible), and the shell-cushioning assembly is held in position within the interior of the fabric portion by inserting the rear-facing end of the assembly into a rear pocket 13 in the fabric portion that has a forward-facing opening to receive the rear-facing end of the shellcushioning assembly. The front-facing end of the shell-cushioning assembly is held in place by a front pocket that, in this embodiment, comprises a portion of a sweatband 14 running so around the interior perimeter region of the cap 1.

The cushioning member is preferably in the form of a closed cell foam, to provide impact absorption, and may be made e.g. from a material such as polyethylene having a hardness of 35°+/-10° and a density of approximately 80+/-10kg.m³. In this embodiment, the cushioning 35 member has the form of an array of raised regions 15 having a height of ca. 10mm interspersed with holes 16 to allow air to flow to a user’s head.

Figures 3A-3C illustrate an embodiment of a substantially rigid shell member 17 forming part of an embodiment of a cap 1 of the invention in plan, end elevation and side elevation views respectively. The shell member 17, known in itself, is shaped so as to conform approximately to the shape of a typical user’s skull in the cranial, forehead and occipital regions. The primary purpose of the shell member 17 is to provide protection against penetrating injuries, and may be made of plastics, such as ABS (acrylonitrile butadiene styrene block copolymer). A particularly suitable material would be the ABS sold under the registered trade mark RONFALIN® STA32. This has a yield stress of 40 MPa, a flexural modulus of 2000 MPa at 23°C, a ball indentation hardness of 80 MPa, and an Izon impact (notched) value of 40 kJ/m² io at23°C.

The mechanical properties of the material, combined with the shape and thickness of the shell member 17 produce a shell that is substantially rigid (i.e. to hold its shape), but having enough flexibility to be able to conform more closely to a particular user’s skull when in use is in a bump cap 1.

The shell member is provided with an array of holes 18 to allow air to pass through, for ventilating the skull, and also a series of attachment lugs 19 to allow a cushioning member 12 to be affixed to the concave surface of the shell 17.

Figures 4A-4B illustrate, for reference, part of a known embodiment of a wheel ratchet mechanism for use in an embodiment of the invention. Within the mechanism is an annular ring 20 having a ratchet 21 defined on its inner surface. A double-pawl arrangement 22 is located for rotation within the ring 20, the arrangement 22 comprising two resilient pawls 23.

In use, torque may be applied to the pawl arrangement 22 via a pair of pins 24 attached to a tensioning knob (not illustrated). Turning the pins in a clockwise direction (as seen in Figure 4A) about the central axis, causes the pins to abut the pawl arrangement 22 and thereby turn it in a clockwise direction. The pawls 23 flex to allow them to pass over the ratchet features 21. When released, the interaction of the pawls 23 with the ratchet 21 prevent anti-clockwise movement of the pawl assembly 22.

When the pins 24 are rotated in an anticlockwise direction, they abut and flex the resilient pawls 23 inwardly, and thereby disengage them from the ratchet 21, allowing the adjustment to be reversible.

Figure 4B illustrates the rear face of the pawl assembly 22 onto which is fixed a cog 25. The cog 25 is not illustrated in Figure 4A, for sake of clarity.

Figure 5 illustrates part of an embodiment of a wheel ratchet mechanism for use in an embodiment of the invention. For sake of clarity, the pawl assembly 22 and ring 20 are not illustrated. Two elongate tensioning members 26 are slideably located in a channel 27. The 5 ends of the tensioning members within the channel are provided with teeth 28 to engage with the cog 25 portion of the pawl assembly 22. Together, these elements create a rack and pinion assembly such that rotational movement of the cog 25 is converted to opposing linear movement of the tensioning members 26, thereby allowing the length of the connector 10 to be adjusted.

io

Tn this embodiment of a connector, one end of each of the tensioning members 26 is provided with an anchor 29 in the form of a substantially flat enlarged portion (with respect to the dimension of the tensioning member’s arm 30). In the embodiment, each anchor is essentially triangular in shape, but other shapes are also envisaged, e.g. rectangular, T-shaped, circular is etc. Unlike known adjustable length connectors that are typically attached to cradles of safety helmets or cycle helmets, the provision of these anchors 29 allow the tensioning member 26 to be used in the context of fabric-covered bump caps.

In addition, the arms 30 of the tensioning members 26 are provided with a curved portion 31 20 so that, when attached to a bump cap, the toothed regions of the tensioning members 26 he approximately parallel to each other.

Figures 6-9 illustrate embodiments of bump caps 1 of the invention. Elements of the caps 1 previously described are indicated by the same reference numbers. In each embodiment an 25 adjustable length connector 26 comprising a wheel ratchet connects two spaced-apart joining regions 32 of the fabric portion 2 of the cap 1.

In the embodiment of Figure 6, the joining regions 32 are located at each end of a “cut-away” portion 33 at the rear of the fabric portion 2 of the cap 1. In this way, adjustment of the length 30 of the connector 26 draws the two sides of the cut-away portion 33 together, thereby allowing the cap 1 to be reversibly tightened onto the head of a user.

In the embodiment of Figure 7, the connector 26 is located in a temple region of the cap 1, with the joining regions 32 located at each side of a fabric panel 34. In a similar fashion, adjusting the length of the connector 26 draws the two joining regions 32 together, providing the required adjustment. Such connectors could be located on one or on both sides of the cap

1. It is preferred that the connector 26 is located at the rear of the cap 1, situated in use adjacent a nape region of a user’s neck, but an arrangement of the type shown in Figure 7 is an envisaged embodiment should there be a reason to avoid having the connector 26 located adjacent a user’s neck.

Figures 8 and 9 illustrates embodiments of a cap 1 of the invention in which the connector 26 is located at the rear of the cap 1 between two joining regions 32 located at either side of a fabric panel 34. As the length of the connector 26 is reduced, the joining regions are drawn together, causing the cap to be releasably tightened onto a user’s head. When so tightened, the fabric panel can ruck, as illustrated in Figure 9. In alternative embodiments, the fabric io panel 34 might also be formed from elastic or elasticated material to prevent such rucking.

In any of the embodiments of Figures 6-9, is especially preferred that the connector is joined to the fabric portion 2 of the cap 1 in the way now described with reference to Figure 10.

Figure 10 illustrates part of an embodiment of a bump cap of the invention, generally indicated by 1 in order to particularly describe a preferred method of fixing a connector 26 to a joining region 32 of the cap 1. Elements of the cap 1 previously described are indicated by the same reference numbers. In this embodiment the arms 30 of the tensioning members 26 forming part of the connector 26 are provided with an anchor 29 at one end. Such anchors 29 are described above. A joining region 32 of the fabric portion 2 of the cap 1 (in this embodiment, a downwardly-extending region of the fabric portion 2) is provided during manufacture with an anchor pocket 35, sized and shaped so as to be able to receive an anchor 29 of the tensioning member 26. Preferably, the pocket 35 is only just large enough to receive the anchor 29, so that the anchor 29 is snugly fitted within the pocket 35. Once inside the pocket 35, the anchor 29 can be secured in place by sewing though the material of the pocket 35 and the anchor 29. In this way, the pocket is closed, and a secure attachment is made between the connector 26 and the fabric portion 2.

It is to be understood that the use of the word “comprising” in this description also envisages so the optional use of the term “consisting of’, or “consisting essentially of’.

Claims (7)

1. A bump cap comprising:

(a) a flexible outer fabric portion so sized and shaped as to cover the cranial, forehead

5 and temporal region of a user’s head;

(b) a substantially rigid shell member so sized and shaped as to cover at least the cranial and forehead region of a user’s skull said shell member being mountable within said fabric portion;

(c) a resilient cushioning member so sized and shaped as to cover at least the cranial

10 and forehead front region of a user’s skull said cushioning member being mountable within said shell member;

(d) an elongate adjustable length connector joining two spaced-apart joining regions of said fabric portion such that reducing the length of the connector acts to draw said regions together, thereby securing said cap on the head of a user;

is wherein said adjustment member comprises a wheel ratchet.

2. A bump cap according to Claim 1 wherein said joining regions are located at each end of a cut-away portion of said fabric portion.

20

3. A bump cap according to either Claim 1 or Claim 2 wherein each end of said connector is provided with an anchor comprising a substantially flat enlarged region and each joining region is provided with a pocket to receive and hold a corresponding anchor.

4. A bump cap according to Claim 3 wherein each anchor is sewn within its corresponding 25 pocket.

5. A bump cap according to either Claim 3 or Claim 4 wherein said anchor is triangular.

6. A bump cap according to any preceding claim wherein said connector is configured to lie so against a user’s occipital bone.

7. A bump cap according to any preceding claim wherein a top region of said portion comprises an air-permeable mesh.