The invention relates to a protective helmet, particularly for mountaineers and tree climbers, comprising a helmet shell, interior fittings comprising a subassembly contacting the head of at least one supporting cage, one head band and one neck strap, and means for fixing this subassembly to the helmet shell.
A protective helmet of this type is known from the document DE 87 14 490 U1. This known protective helmet is a basic helmet adjustable to the different purposes under different service conditions by exchanging accessory elements. The protective helmet consists of a helmet shell and minimum interior fittings. The interior fittings are comprised of a crossed strap by means of which the helmet is worn on the head and which ensures a shock-absorbing clearance between the head and the helmet shell. The helmet is, at its outer circumference, provided with a protrusion spanning the lateral and the rear part of the helmet and having four recesses for fixing the crossed strap at the lower edge and further recesses for fixing additional accessory elements. The basic version of the helmet may be used as a simple universal helmet without any accessories. The accessories may be added or removed as required. At the broadest sections of the helmet, a recess is provided at the outside of the protrusion spanning the largest part of the helmet. This is the mounting position for a face and ear protection. This protection consists of a visor and two ear protectors which respectively comprise a wire bracket and an ear protection capsule. The face and the ear protection are fixed to the helmet from the outside by means of a common connecting element which is inserted into the protrusion. A disadvantage of a helmet kitted out like this is that, in service, obstacles the helmet passes may get caught behind the brackets of the ear protection and/or the visor and thus become an encumbrance to the wearer of the helmet in the field or rip the helmet off his head and thereby imperil the wearer.
Other documents describing the mounting of helmet accessories such as a face and/or ear protection on the outside of a protective helmet are the DE 28 26 636 C2, DE 29 07 054 A1, DE 33 14 595 C2, DE 35 90 667 C2, DE 94 10 596 U1 and DE 297 08 134 U1. With the protective helmets known from these documents the wearer of the helmet may also be hampered or imperilled on duty if obstacles get caught on the brackets of the ear and/or face protection.
Further documents concerned with the mutual fixation of interior fitting subassembly and helmet shell, not, however, with mounting helmet accessories on the outside of the helmet shell, are listed below.
From the document DE 10 2004 004 044 B4 a protective helmet is known in which the interior fittings comprising a subassembly contacting the head and comprised of a supporting cage, a head band and a neck strap are provided with connecting elements which are inserted into a shield which, in turn, is fixed on the lower edge of the helmet shell.
From the document DE 698 11 738 T2 a protective helmet is known in which the interior fittings comprising a subassembly contacting the head and comprised of a supporting cage, a head band and a neck strap are fixed with the aid of anchoring links which are inserted into slots at four positions in the lower edge of a double-walled helmet shell. The head band is made of a flexible material which can be easily adjusted to the size and shape of the head of the wearer.
From the document WO 2005/027671 A1 a safety helmet is known in which a shock absorption unit surrounding the remaining interior fittings and comprising a subassembly contacting the head and comprised of a supporting cage, a head band and a neck strap is disposed in the helmet shell. On the inner side of the helmet shell protrusions are provided on which the shock absorption unit and the interior fitting subassembly can be fixed by means of screws. In this known safety helmet the shock absorption unit is formed so thick that it is possible to provide a recess in which a transmitter/receiver having a connection line leading to the outside may be accommodated in its outer side facing the inner side of the helmet.
It is common to all the known protective helmets mentioned above that a force acting on the helmet from above is substantially fully transmitted to the head of the wearer of the helmet via the interior fittings and particularly via a supporting cage formed by a crossed strap. Namely, the crossed strap can only fulfill a shock absorption function to a certain degree because it has the additional function to tightly hold the helmet on the head of the wearer.
There is therefore also a demand for a protective helmet having an improved shock absorption capability.
It is further common to all known protective helmets mentioned above that a force acting on the helmet from the side is also substantially fully transmitted to the head of the wearer of the helmet. In all known helmets the interior fittings extend at least along the lower edge of the helmet directly to the helmet shell so that, at best, padded lace often present at the lower edge of the helmet between the interior fittings and the helmet shell could provide for some shock absorption.
Finally there is the problem that a protective helmet intended for mountaineers and tree climbers has to be provided with a chin strap. The chin strap has to be fixed at the inner side of the helmet shell and at the interior fitting assembly. If a pull is exerted on the chin strap, for example during a tensile test as required for a certification of the protective helmet, the position of the fastening points of the chin strap on the protective helmet has to remain stable. The interior fittings may therefore not become separated from the helmet shell during the tensile test. When the protective helmet is in use the chin strap has to safely keep the protective helmet on the head irrespective of an exposure to an external force or impact.
It is the object of the invention to design a protective helmet of the type mentioned in the beginning and known from the first mentioned document so that it has a substantially improved shock absorption capability both with respect to forces acting on it from above and to forces acting on it from the sides.
The shock absorption capability is also to be improved in a protective helmet which is the subject matter of the non-prepublished German patent application no. 10 2010 027 012.1. In this prior suggestion of the applicant a clearance is present around the interior fitting assembly which provides for a free space of up to approx. 4 cm between the interior fittings and the inner side of the helmet shell on all sides. In case of forces acting from the sides this clearance is used to reduce the impact energy by a deformation of the helmet shell and the interior fitting assembly. The standard in fact also requires a clearance between the upper side of the interior fitting assembly and the inner side of the helmet shell disposed above it, however, the known protective helmets therefore only afford protection against impacts occurring from above, if any at all.
According to the invention the object is solved by the fixation means comprising at least three support arms formed as spacers which project laterally downwards from the support cage into the temple area or backwards and downwards in the area of the back of the head, by the helmet shell and the support arms being dimensioned so that the interior fixation subassembly is continuously held in a distance from the helmet shell along its entire outer circumference so that a clearance extending around the interior fixation subassembly on all sides for accommodating helmet accessories comprising at least ear protection capsules along with supporting brackets and a tightening unit for the neck strap as well as mounting devices for the ear protection and for other helmet accessories comprising at least a face protection and a chin strap exists between the interior fitting subassembly and the helmet shell, by the supporting arms being releasably fixed to the helmet shell at their free end, respectively, and by the releasable fixation of the support arm protruding backwards and downwards comprising a latch fastener effective in a longitudinal direction of the same at a rear fixation point on or in the helmet shell, and, in addition, a mounting suspension of this support arm on an upper fixation point above the latch fastener on the inside of the helmet shell.
In the protective helmet according to the invention a neck strap tightening unit and mounting devices for at least an ear protection as well as ear protection capsules are located inside of the helmet shell so that the supporting brackets and retaining arms of the face and ear protection are disposed within the perimeter of the protective helmet so that it offers no possibilities for an engagement of obstacles such as branches and the like on its outside. If the ear protection is not needed it may, furthermore, be pivoted backwards inside the perimeter of the protective helmet within the clearance present between the interior fitting subassembly and the helmet shell so that the helmet offers even less engagement positions for obstacles. Since the mounting devices for the face protection are also disposed in the clearance the visor can be designed so that it offers engagement possibilities for obstacles such branches or the like neither in the tilted-up nor in the tilted-down state. The support arms arranged as spacers between the interior fitting subassembly and the helmet shell and the clearance formed thereby, due to a space of up to 4 cm being present between the interior fitting subassembly and the inner side of the helmet shell on all sides, offer the possibility to absorb a force acting on the helmet from the outside by a deformation of the helmet shell and the interior fitting subassembly so that the protective helmet according to the invention has an altogether better shock absorption capability because less force is transmitted to the head of the wearer. As already explained above, the force may be exerted on the helmet from above or from the side. In case of a lateral exertion of a force the shock absorption will then be achieved by pivoting and shifting the helmet shell relative to the interior fixation subassembly According to the invention, this is rendered possible by the, as compared to the state of the art, wide clearance between the interior fixation subassembly and the helmet shell in which not only the helmet accessories can be accommodated, but in fact also with the aid of the support arms connected to the helmet shell, which do not only act as spacers but will, under a tensile load applied by the helmet shell when a force is exerted on it from above or from the side, deform themselves and the supporting cage to which they are connected, and absorb the energy applied by the effects of the blow in this way, and thereby protect the head from the effects of the impact.
In the protective helmet according to the invention the wide free space present between the helmet shell and the interior fittings around the interior fittings renders the accommodation of helmet accessories comprising at least ear protection capsules of an ear protection and a tightening unit for the neck strap possible. In the protective helmet according to the invention the support and shock absorption functions are combined in the supporting cage made of a stiff, elastically flexible material in combination with the helmet shell having a certain elastic plasticity at least about its longitudinal axis. In fulfilling the shock absorption function, therefore, the supporting cage is supported by the helmet shell since the support arms protruding laterally downwards support the supporting cage on the helmet shell with their free ends so that in case of an external pressure acting on the helmet shell from above a tensile load is applied to the supporting arms by the helmet shell whereby the supporting arms are striving to deform the helmet shell towards the inside. When a force is acting on the helmet from the side the shock absorption function is additionally supported by the helmet shell which is only connected to the interior fittings at three fixation points and widely spaced apart from the interior fittings all around being dislocated relative to the interior fittings. As a result of this dislocation, but also in consequence of the tensile and compressive forces transmitted to the support arms of the interior fixation subassembly protruding laterally downwards via the helmet shell these support arms are deformed, whereby a shock impulse acting on the helmet is alleviated.
According to the invention the releasable fixation of the support arm protruding backwards and downwards comprises a latch fastener effective in its longitudinal direction at a rear fixation point on the helmet shell and a mounting suspension or support effective in its transverse direction at an additional fixation point located on the inside of the helmet shell in a distance to the latch fastener. In this way the support arm protruding backwards and downwards is prevented from giving up its snap-on connection to the helmet shell or from allowing the helmet shell more tolerance than absolutely required for the dislocation. The helmet shell is thus dislocated or pivoted in a controlled manner when a lateral force is applied, and impact energy is dissipated thereby. The shock absorption function is mainly achieved by an elastic deformation of the supporting cage and the supporting arms protruding laterally downwards which are attached to it in case of a dislocation or pivoting motion. The additional fixation point may be disposed above or below the latch fastener.
The support arm protruding backwards and downwards and its fixation on and in the helmet shell have an important function here, which will be explained in more detail here. The helmet shell has a substantially elliptical cross section. The longitudinal axis of the ellipse extends in the direction from the front side to the rear side or vice versa. The smaller curvature radius of the ellipse is therefore located at the front and rear ends of the helmet shell. If the helmet shell is deformed by an external force acting on it or from the inside by the interior fixation subassembly being distorted more force is required for the deformation where the radius is smaller, i.e. on the front and on the rear side, than where the curvature radius is larger, i.e. at the two long sides of the helmet shell. In the area in which the ellipse has the smaller curvature radius, i.e., for example, on the rear side, the helmet shell is capable of enduring a larger tensile force. If, as a thought experiment, the same tensile force was acting on all areas of the helmet shell, i.e. on the lateral sections as well as on the rear and front section, the deformation of the lateral sections towards the inside would be much more intense because smaller tensile forces are sufficient to this end. The support arm protruding backwards and downwards has a flatter angle relative to the helmet shell than the supporting arms protruding laterally downwards. Therefore, more deformation force is applied to the rear section of the helmet shell than to the lateral sections, approximately 50% on the rear side and respectively 25% in the lateral sections. This results in a main difference to all known helmets. If the effects of an impact from above act on a known helmet only the top of the known helmet will be deformed. Given the same effects of an impact, however, the helmet shell of the protective helmet according to the invention will be deformed altogether, i.e. not only in the upper section, but also in the lateral areas. Even though, on principle, the deformation energy is introduced into the entire helmet shell in the protective helmet according to the invention, it is also so that, as a result of the flat inclination of the support arm protruding backwards and downwards, and due to the smaller radius at the rear end of the helmet shell, a greater force transmission takes place at the rear fixation point where the free end of the support arm protruding backwards and downwards is fixed to the helmet shell than in the area of the long sides of the helmet shell so that an altogether stable force effect on the entire helmet shell is achieved.
The mounting suspension of the support arm protruding backwards and downwards provides for additional support on the helmet shell in case of an impact effect from above. Furthermore, this additional mounting suspension counteracts tensile forces acting on the interior fixation subassembly by the chin strap when it is exposed to strain.
Finally, the three-point-fixation between the interior fixation subassembly and the helmet shell preferred for the protective helmet according to the invention provides for the required degrees of freedom between helmet shell and interior fixation subassembly Their mutual dislocation enables a distortion of at least the two supporting arms protruding laterally downwards and, with it, a corresponding deformation of the helmet shell and the interior fixation subassembly so that the protective helmet has excellent shock absorption capabilities even with regard to the effects of lateral impacts.
The particular advantage the invention offers with regard to the force transmission within the helmet shell is also based on the finding that, for this purpose, three fixation points between the interior fixation subassembly and the helmet shell are optimum. If the mounting suspension of the helmet shell on the interior fixation subassembly is implemented at four or more points as in the state of the art the combination of helmet shell and interior fixation subassembly becomes extremely stable. They can hardly pivot or dislocate relative to each other so that their deformation which would contribute to the shock absorption will hardly occur.
The support arm protruding backwards and downwards is prevented from giving up its snap-on connection to the helmet shell or from allowing the helmet shell more tolerance than absolutely required for the displacement by the additional mounting suspension or support in case of an external force effect acting on the helmet shell and manifesting itself in a tensile load applied to this supporting arm. The helmet shell is therefore dislocated or pivoted relative to the interior fixation subassembly in a controlled manner when a lateral force is applied so that impact energy is dissipated.
The additional mounting suspension or support of the support arm protruding backwards and downwards on the helmet shell offers additional advantages in the tensile strength test required for certification which has to be passed by such protective helmets before they are approved for sale. In this tensile strength test it is, among other things, examined whether a chin strap which is mandatory in some helmets, for example, mountaineer's and tree climber's helmets, is capable of separating the entire helmet from the head of the wearer at a prescribed tensile load. The mounting suspension does not only lead to a stabilisation of the fixation of the support arm protruding backwards and downwards on the helmet shell but also absorbs a large part of the force during the peeling test and prevents the supporting arm protruding backwards and downwards from being stained by the tensile load to the point that it gives up its snap-on connection to the helmet shell. The angle formed by the support arm protruding backwards and downwards and the longitudinal axis of the helmet shell is very flat so that a higher tensile force is applied to this supporting arm in case of a force acting on the helmet from above and may therefore render a correspondingly substantial contribution to the shock absorption in case of strain from above. Owing to the stabilisation resulting from the mounting suspension the tensile force absorption capacity of the support arm protruding backwards and downwards is considerably improved. According to the state of the art described in the beginning, for example according to the document DE 1 797 962 U1, the angle formed by the support straps on the supporting cage and the inner side of the helmet is so acute, that, in case of a force being applied from above, the force is virtually introduced into the helmet shell in the direction of the helmet shell via the support straps. Forces introduced into the helmet shell in this way are, of course, not capable of supporting the shock absorption function because they do not create any tendency to deform towards the inside in the area of its long edges. In the state of the art a substantial inwards deformation of the helmet shell would be rather counterproductive anyway because, other than in the protective helmet according to the invention in which an up to at least about 4 cm wide clearance is present between interior fittings and helmet shell on the level of the lower edge of the helmet shell. The helmet shell is already located very close to the head of the wearer of the helmet in the initial state The clearance permits a considerable deformation of the helmet shell towards the inside without there being the risk of the helmet shell contacting the head. It is rather ensured that in consequence of its deformation a substantial part of the impact energy is dissipated. The preferred three-point fastening of the helmet shell on the interior fixation subassembly and the wide clearance between them set the stage for this in the protective helmet according to the invention.
In case of a lateral load acting on the helmet shell the conditions in terms of shock absorption are even less favourable than in case of strain applied from above in the known protective helmets. In the known helmets as discussed in the beginning, typically, the interior fittings are mounted directly on the lower side of the helmet edge If a blow from the side acts on the helmet shell this blow will be directly transmitted to head. The fact that sometimes a padded lace is present between the helmet shell and the interior fittings on the level of the lower edge of the helmet shell like, for example, in the helmet according to the abovementioned document DE 1 797 962 U1 will be of no assistance either since such padded lace has only a small thickness and can therefore be compressed almost without resistance by the helmet shell moving inwards.
Advantageous embodiments of the protective helmet according to the invention from the subject matter of the sub-claims is.
In one embodiment of the protective helmet according to the invention an intermediate part of the support arm protruding backwards and downwards positioned in the clearance is fixable or fixed to a retaining part on the helmet shell disposed above or below it in a distance for connecting the support arm protruding backwards and downwards to the additional fixation point. In this way the supporting arm protruding backwards and downwards is, even under the most adverse force effect conditions acting on the helmet shell, prevented from giving up its snap-on connection to the helmet shell or from allowing the helmet shell more than the tolerance absolutely required for a dislocation relative to the interior fixation subassembly The additional fixation of the intermediate part of the supporting arm protruding backwards and downwards located in the clearance to a retaining part on the helmet shell located above it in a distance may, for example, be implemented by an arm extension, bridge or the like integrally formed on the intermediate part and establishing a substantially rigid connection between the intermediate part and the retaining part located above it on the helmet shell.
In another embodiment of the protective helmet according to the invention the supporting cage is formed of a stiff, elastically flexible material. In the protective helmet according to the invention the support and the shock absorption function are combined in the supporting cage of a stiff, elastically flexible material and the supporting arms protruding from it of the same or the identical material in this embodiment. In fulfilling the shock absorption function the supporting cage is supported by the helmet shell because the supporting arms protruding obliquely downwards or backwards support the supporting cage on the helmet shell with their free ends so that at least the laterally protruding supporting arms are exposed to a tensile load by the helmet shell and strive to deform the helmet shell towards the inside down to the lower edge at its long sides when an external pressure acts on the helmet shell from above.
In another embodiment of the protective helmet according to the invention the mounting device for the chin strap comprises two chin strap fastening points on the inside of the helmet shell to which suspension links of the chin strap can be connected and a rear chin strap fastening point on the interior fitting subassembly. The position of these fixation points for the chin strap ensures a safe fixation of the same.
In another embodiment of the protective helmet according to the invention the rear chin strap fixation point comprises an aperture in the support arm protruding rearwards and downwards to which another suspension link of the chin strap can be attached. The chin strap can thus be fixed to the interior fitting subassembly in a simple manner after the assembly of the interior fitting subassembly in the helmet shell. The use of suspension links in the three fixation points of the chin strap renders their convenient exchangeability possible, for example for cleaning purposes.
In another embodiment of the protective helmet according to the invention the supporting cage comprises, at its lower edge, a peripherally closed support strip on which the support arms are integrally formed. In this embodiment the supporting arms and the support strip form an integral component having the required stiffness and yet offering a sufficient shock absorption effect together with the remaining part of the supporting cage. Particularly in the area between this support strip and the helmet shell the latter is spaced apart from the supporting cage by at least about 4 cm along its entire circumference.
In another embodiment of the protective helmet according to the invention the neck strap is attached to the supporting cage and has two ends releasably connected in the neck area by a tightening unit accommodated in the clearance as another helmet accessory. The neck strap is thus also protected against the external effect of obstacles and still conveniently accessible for the operation by the wearer of the helmet.
In another embodiment of the protective helmet according to the invention the tightening unit comprises a supporting shell which can be tightened against the back of the head of the wearer of the helmet when tightening the neck strap with the aid of a latch flap. This embodiment ensures a reliable one-hand operation and, above that, permits the fixation of the interior fitting subassembly on the head in a simple manner. The use of a chin strap will then offer additional safety.
In another embodiment of the protective helmets according to the invention the chin strap is lead backwards to the tightening unit from the two front chin strap fixation points, ran through the supporting shell on both sides, and finally brought together at the rear chin strap fixation point. When a tensile load is applied to the chin strap its end which is attached to the supporting arm protruding backwards and downwards will pull downwards on the supporting cage. Directly above or below it the additional fixation point is located in which the supporting arm protruding backwards and downwards is suspended or supported on the inside of the helmet shell. The tensile force of the chin straps acting downwards is absorbed by the helmet shell in this way. The chin strap obtains the downwards direction of its tensile force by being led through the tightening unit in its sector located in front of the rear fixation point.
In another embodiment of the protective helmet according to the invention the support arms protruding laterally downwards in the two temple areas comprise means for a releasable fixation on the inside of the helmet shell. The interior fitting subassembly can therefore be readily and releasably attached to the helmet shell.
In another embodiment of the protective helmet according to the invention the fixation means on each of the support arms protruding laterally downwards are formed so that they can be brought in a positive engagement with the helmet shell. In this way, a force can be transferred through the mounting position for the interior fitting subassembly on the inside of the helmet shell in a simple manner.
In another embodiment of the protective helmet according to the invention the support arm protruding backwards and downwards comprises a locking device for a fixation of the support arm to the helmet shell for its latch lock at its free end. In this embodiment the helmet shell may simply have an aperture into which the free end of the above supporting arm is inserted so as to be latched to the helmet shell so as to be capable of transferring a force via the mounting position.
In another embodiment of the protective helmet according to the invention the fixation means on each of the supporting arms protruding laterally downwards comprises through-holes respectively encompassing rod-like protrusions on the helmet shell on a length at least equal to the inner width of the through-holes so that a force exerted to the supporting arms protruding laterally downwards as a result of a load acting on the helmet from above generates a momentum at these supporting arms which strives to deform the helmet shell towards the inside as far as to the lower edge. In this embodiment thus the shock absorption function of the interior fitting subassembly can be supported in a simple manner by the elastic deformation of the helmet shell. The through-holes at the free ends of the supporting arms are adjusted depending on the rod-like protrusions so that a leverage effect can be exerted on the rod-like protrusions when a force acts on the helmet shell. Here, the support of the shock absorption function will not only take place when a force acts on the helmet from above but also when a force is exerted on the helmet from the side. In the latter case a controlled dislocation or pivoting of the helmet shell relative to the interior fixation subassembly will lead to a tendency of the supporting arms to become distorted and therefore also of the supporting cage to become distorted which considerably contributes to the shock absorption. What is helpful here is that the supporting arms are designed so that they are extremely wide which facilitates their distortion by the helmet shell when they are dislocated or pivoted relative to the interior fixation assembly.
In another embodiment of the protective helmet according to the invention the supporting cage comprises two support arms protruding downwards to which the neck strap is respectively fixed on a selectable level. In this way the fit of the protective helmet can be improved in a simple manner.
In another embodiment of the protective helmet according to the invention the support arms and the support arms are further stiffened by integrally formed ribs. In this way, the force transmission via the mounting position can be ensured in a simple manner.
In another embodiment of the protective helmet according to the invention the intermediate part of the support arm protruding backwards and downwards disposed in the clearance is provided with at least one bridge protruding upwards or downwards for the additional mounting suspension or support in the additional fixation point on the helmet shell. The bridge ensures that a force exerted when a force acts on the support arm protruding downwards from above via the helmet shell will not only act on the free end of this support arm which is latched to the helmet shell but also on the intermediate part of this support arm disposed in the clearance. In case of a lateral force acting on the helmet the bridge will act as a stabiliser because it permits a dislocation or pivoting movement of the helmet shell relative to the interior fixation subassembly in case of a lateral force acting on the helmet shell but will prevent the snap-on connection between the supporting arm protruding backwards and the helmet shell from being released, loosened or becoming appreciably dislocated.
In another embodiment of the protective helmets according to the invention the bridge is integrally formed with the supporting arm protruding backwards and downwards. Since the supporting cage is preferably made of a plastic material and the supporting arm protruding backwards is integrally formed with the supporting cage the bridge can be integrally formed with the supporting cage in a simple manner.
In another embodiment of the protective helmets according to the invention the free end of the bridge is formed so that it is positively fixable to the retaining part on the helmet shell. This is the most effective way to accomplish that the bridge attached to the inside of the helmet shell behaves like the helmet shell and that their mutual connection can be readily designed so that can be easily detached, for example when dismounting the interior fitting subassembly from the helmet shell.
In another embodiment of the protective helmet according to the invention the supporting arm protruding backwards and downwards is bifurcated at its free end and latched on the helmet shell with both bifurcated ends thus formed and provided with a pair of the bridges which are aligned in parallel with respect to each other and spaced apart by the width of the arm in its intermediate part. This renders latching the fork-like free end in an aperture in the helmet shell possible in a simple manner while rapidly fixing the entire width of the supporting arm protruding backwards and downwards to the pair of bridges on the inside the helmet shell.
In another embodiment of the protective helmet according to the invention the support arms protruding laterally downwards form an angle in a range of approximately 30°-50° together with a straight line extending transversely relative to the longitudinal axis of the supporting cage and through the free ends of these support arms. Within this range, an optimum value for the force effect in terms of the desired support of the shock absorption function can be selected. A preferred value is approximately 45°.
In another embodiment of the protective helmet according to the invention the support arm protruding backwards and downwards forms an angle in a range of about 15°-25° with the longitudinal axis of the supporting cage. A preferred value is approximately 20°.
In another embodiment of the protective helmet according to the invention the support arms protruding laterally downwards are arrow-shaped in the forward direction and formed on the supporting cage in front of a central transverse axis of the supporting cage. The supporting arms protruding laterally downwards therefore do not protrude straightly sideward but transversely forward in this embodiment. In this way the forces can be more optimally distributed on the helmet shell from the pivot points. The good distribution of the forces on the helmet shell provides for the same being substantially evenly deformed all around.
In another embodiment of the protective helmet according to the invention the helmet shell comprises ventilation openings and guide slots for retaining elements of a ventilation gate at least in an area following the snap-on connection point of the support arm protruding backwards in the forward direction. The ventilation openings render a good ventilation of the clearances present between the helmet shell and the interior fixation subassembly possible. The guide slots enable the ventilation gate to be releasably and shiftably mounted on the helmet shell by means of retaining elements mounted on its bottom side.
In another embodiment of the protective helmet according to the invention the retaining elements of the ventilation gate comprise a pair of angle elements in its front section and a pair of resiliently deflectable retaining arms in its rear section which are shiftably and releasably held in their associated guide slots. A releasable installation of the ventilation gate on the helmet shell is therefore possible in a simple manner.
In another embodiment of the protective helmet according to the invention the ventilation gate is formed so that it shields the section of the helmet shell in which the support arm protruding backwards and downwards is fixable or fixed from the effects of impacts from the outside.
In the following, embodiments of the invention will be described in more detail with reference to the drawings in which:
An embodiment of a protective helmet according to the applicant's prior suggestion designated by 30 as a whole and formed particularly for the use in forestry is shown in a side view in
Three supporting arms 54, 55 and 56 formed as spacers of which the supporting arm 55 is not visible in
In the following the helmet shell 36, the interior fitting subassembly 40, its connection to the helmet shell 36 and then the helmet accessories comprising the ear protection 34, the face protection 32 as well as their mounting devices and the tightening unit 48 as well as the chin strap 300 and its fastening device 380 will be described in detail and in this order.
In the following, the helmet shell 36 will be described in detail with reference to the drawings, particularly to
The helmet shell 36 is formed as an integrally formed plastics moulding. A suitable plastic material for the helmet shell 36 is, for example, ABS. In
The lower edge of the helmet 30 is laterally drawn downwards in the area of the temples and in the area of the back of the head as can be seen in
In the abovementioned temple area three rod-like protrusions 74a or 74b to which the interior fitting subassembly 40 including the supporting arms 54 or 55 can be positively and releasably attached are integrally formed on each side of the inside of the helmet shell 36. The rod-like protrusions 74a, 74b can be seen in a side view in
At the centre of the rear end the helmet shell 36 is provided with a recess 76 at the lower edge behind which the tightening unit 48 of the neck strap 46 is located so as to be accessible for a manual operation for tightening or releasing the neck strap 46 when the helmet 30 is fully assembled.
To lock the supporting arm 56 on the helmet shell 36 it is provided with at least one slot 78 in the area of the back of the head in which the appropriately formed free end of the supporting arm 56 (
A mounting device 80 for the ear protection 34 comprises two ear protection supporting points 80a, 80b on the inside of the helmet shell 36. The ear protection supporting points 80a, 80b are pivot bearings integrally formed on the inside of the helmet shell 36 or, preferably, non-releasably mounted as additional parts. On the ear protection supporting points 80a, 80b, supporting brackets 37a, 37b including ear protection capsules 35a or 35b are pivotably supported as described in more detail further below.
A mounting device 84 for the face protection 32 is provided with two face protection supporting points 84a, 84b on the inside of the helmet shell 36. In the face protection supporting points 84a, 84b two retaining arms 132a, 132b of a visor 132 are pivotably supported. The face protection supporting points 84a, 84b are not integrally formed on the inside of the helmet shell 36 but respectively fit onto a connector 136a or 136b respectively snapped on the rod-like protrusions 74a or 74b to thereby simultaneously fix the free ends of the supporting arms 54, 55 on the rod-like protrusions. The face protection supporting points 84a, 84b including the connectors 36a or 36b allocated to them are located in the clearance 60 in the mounted state, namely in an area in which the helmet shell 36 is drawn downward at its lower edge as already explained above.
The interior fittings for the protective helmet 30 will be described in detail below with reference to the drawings, particularly
The supporting cage 42 is formed of a stiff, elastically flexible material, preferably of a plastic material such as polyamide. The support head 42 is respectively provided with a rigid supporting arm 54, 55 or 56 protruding obliquely downwards or backwards and downwards in two temple areas as well as in an area of the back of the head to form a three-point mount of the interior fittings to the helmet shell 36 and for enabling the clearance 60 continuously extending around the interior fittings in the helmet shell 36 to accommodate ear protection capsules 35a, 35b and other helmet accessories as well as mounting devices 80, 84 for the face and the ear protection 32 and 34. The supporting cage 42 is produced as an integrally formed plastic moulding in the embodiment described here. The supporting cage 42 is formed of two pairs of mutually spaced apart support strips 142, 144 which, according to the representation in
The supporting arms 54, 55, 56 protrude downwards from the supporting cage 42 at the connection points 146a, 146b, 146c. If it is assumed that the support strips 142 and 144 extend in a curve, preferably in a substantially circular arc, between the connection points 146a, 146b or 146c, 146d the supporting arms 54, 55 or 56 respectively protrude laterally downwards or backwards and downwards from the supporting cage 142 so as to be substantially tangential to the related curve as can be seen in
In the embodiment described above the supporting arms 54, 55 are, actually, attached to the helmet shell 36 in a different way from the supporting arm 56 however, this is not essential. The supporting arms 54, 55 may also be fixed to the helmet shell in the same way as the supporting arm 56 To this end, it would only be required that the supporting arms 54, 55 have fixation means identical to those of the supporting arm 56 which permit the supporting arms 54, 55 to be brought into a positive engagement with the helmet shell. In this case then the fixation means of the supporting arms 54, 55 would also be locking means which are, for example, inserted into slots in the helmet shell 36 to fix the supporting arms 54, 55 as well as the supporting arm 56 on the helmet shell by means of a locking connection.
The head band 44 is integrally formed on the peripherally closed support strip 148 via connecting strips 150 in a distance to the peripherally closed support strip 148. The supporting arms 54, 55, 56 and the support arms 47a, 47b are further reinforced by integrally formed ribs 152 or 154.
The supporting arms 54, 55 protruding laterally downwards in the two temple areas comprise means for the fixation to the inside of the helmet shell 36. The fixation means comprise three through-holes 156 or 158 in each of the supporting arms 54, 55 which can be brought into a positive engagement with the rod-like protrusions 74a or 74b on the helmet shell 36. The supporting arm 56 of the supporting cage 42 protruding backwards in the area of the back of the head is provided with the protrusions 56a, 56b which, as already explained above, form a locking device for releasably attaching the interior fitting subassembly 40 to the helmet shell 36.
In industrial and forestry workers' helmets a chin strap is usually fastened to the helmet shell or to the supporting cage. In the protective helmet 30′ according to the invention the chin strap 300 (
The mutual connection of the helmet shell 36 and the interior fitting subassembly 40 which was already partly described above will be explained in summary and complementary here with reference to
In the following the ear protection 34 including its mounting device 80 will be described in more detail with reference to the drawings, particularly
The ear protection 34 comprises two ear protection capsules 35a, 35b which are, respectively, pivotably supported in a fork-like supporting bracket 37a or 37b. The helmet shell 36 is provided with the fixed ear protection supporting points 80a, 80b at its inner side as can be seen in
Each supporting bracket 37a, 37b is formed so as to be spring-biased and bendable in an area between its two ends in which it extends within the clearance 60 so that the ear protection capsules 35a, 35b are respectively pivoted away from the ear in a non-bent posture of each supporting bracket 37a, 37b as shown in
Furthermore, each ear protection supporting point 80a, 80b and each supporting bracket 37a, 37b are formed so that the supporting bracket can only be pivoted backwards from the position shown in
In the following the face protection 32 will be described in more detail with reference to the drawings, particularly
The face protection 32 comprises the visor 132 comprising the two retaining arms 32a, 32b as well as two connectors 136a, 136b on which a face protection supporting point 84a or 84b is integrally formed as a mounting device 84 for the face protection 32, respectively. The connectors 136a, 136b are fitted on the rod-like protrusions 74a or 74b whereby the face protection supporting points 84a, 84b come to be positioned in the temple area on the inside the helmet shell 36. The connector 136b including the face protection supporting point 84b can be seen in
The visor 132 forms a fork together with each retaining arm 132a, 132b (
In the following the tightening unit 48 will be described in more detail. Alongside the ear protection 34, the tightening unit 48 is another helmet accessory which, like the ear protection 34, is always located within the perimeter of the helmet shell 36 so that, in the area of the tightening unit 48 as well, no protruding parts exist on which obstacles might get caught. The tightening unit 48 will be described with reference to the drawings, particularly to
The tightening unit 48 comprises a mount 168 into which the free ends of the neck strap 46 are inserted on both sides. The mount 168 is provided with angular cams which can be brought in engagement with angular orifices 176 of the neck strap 46. In this way the length of the neck strap 46 can be crudely adjusted depending on the size of the head. The adjustment is appropriately carried out so that the protective helmet 30 can be conveniently put on when the tightening unit is not operated. The tightening of the neck strap 46 will then be effected with the aid the tightening unit 48 after the helmet 30 was put on as explained below.
According to the representation in
The tightening unit 148 is operated by means of a latch flap 174 which is, according to
The operation of the tightening unit 48 is effected by means of the latch flap 174. If the latch flap 174 is pivoted clockwise and thus closed as shown in
Now, an embodiment of the protective helmet 30′ according to the invention mainly differing from the embodiment of the protective helmet 30 according to the applicant's prior suggestion in an additional stabilisation of the fixation points of the supporting 55 arm protruding backwards and downwards of the interior fixation subassembly 40 and in the accordingly modified embodiment of the fixation of this supporting arm on the helmet shell will be described with reference to
Another difference is the provision of the chin strap 300 and its type of fixation on the helmet shell 36 and the interior fixation subassembly 40 according to the illustration in
Finally, yet another difference resides in the design of the fixation of the ventilation gate 50′ which is tailored to the modified fixation of the supporting arm 56 on the helmet shell 36 according to the illustration in
The protective helmet 30 according to the applicant's prior suggestion can be provided with a helmet shell and interior fixation subassembly adapted to the differences described above and will then be equivalent to a protective helmet 30′ according to the present invention in all embodiments shown here and described for the prior suggestion which may then optionally be provided with a face protection, an ear protection and/or a tightening unit for the head band. The type of attachment of this helmet accessory would not differ from the type of attachment in the protective helmet 30 according to the applicant's prior suggestion so that the drawings and the description of the protective helmet 30 according to the applicant's prior suggestion are enclosed here for the sake of simplicity so as to avoid an additional illustration and description of the protective helmet 30′ according to the invention and of the mentioned helmet accessories and the associated repetitions which would be involved. The protective helmet 30 according to the applicant's prior suggestion, supplemented by the differences described above, is the protective helmet 30′ and therefore part the present invention.
The helmet shell 36 including the mounted interior fixation subassembly 40 is, in its entirety, shown in a plan view in
For its latch lock on the helmet shell 36 the supporting arm 56 protruding backwards and downwards has a latching device formed by the two bifurcated ends 157a, 157b and the slots 178, 179 on its free end. Each bifurcated end 175a, 177b narrows in the area of its protrusion 56a or 56b towards its free end, namely from a aperture 159a or 159b. During the assembly of the interior fixation subassembly 40 the helmet shell 36 is positively accommodated in the openings 159a, 159b. The intermediate part 200 of the supporting arm 56 is then positioned in the clearance 60 present between the inner side of the helmet shell 36 and the supporting cage 42 as soon as the interior fixation subassembly 40 is mounted in the helmet shell.
The intermediate part 200 (
The supporting arm 56 protruding backwards and downwards is latched in the slots 178, 179 at its two bifurcated ends 157a, 157b on the helmet shell 36 in the manner described above. The bridges 212, 214 are aligned in parallel relative to each other and spaced apart by the width of the supporting arm 56. The supporting arm 56 protruding backwards and downwards forms an angle β in a range of approx. 15°-25° with a longitudinal axis 242 of the supporting cage 42 (
For mounting the interior fixation subassembly 40 in the helmet shell 36 the interior fixation subassembly 40 is fit on the rod-like protrusions 74a, 74b on the helmet shell 36 with the fixation means on each of the supporting arms 54, 55 protruding laterally downwards which comprise through holes 156, 158. Prior to this, the supporting arm 56 protruding backwards and downwards is inserted into the slots 178, 179 with its bifurcated ends 157a, 157b until the helmet shell 36 is latched in the slots 178, 179. Then, the supporting arms 54, 55 protruding laterally downwards will abut on the base of the rod-like protrusions 74a, 75b. In the course of this process the two bridges 212, 214 have been shifted on the walls 220, 222 until openings 228, 230 formed in the bridges 212, 214 are latched on the retaining parts 210, 212 as shown in
As already explained above, the inclination angles formed by the supporting arms 54, 55 protruding laterally downwards and the supporting arm 56 protruding laterally backwards and a horizontal plane or an axis located in this plane constitute essential embodiments of the invention. So the supporting arms 54, 56 protruding laterally downwards and a straight line 244 extending perpendicular to the longitudinal axis 242 of the supporting cage 42 and through the free ends of said supporting arms 54, 55 form an angle α in a range of approx. 30°-50°. The supporting arm 56 protruding backwards and downwards and the longitudinal axis 242 of the supporting cage 42 form an angle β in a range of approx. 15°-25°. These angles are important for the force transmission into the helmet shell 36 so that it can be deformed so that it will optimally contribute to the overall damping capacity of the protective helmet 30′ when a load is applied from above or also from the side. Above that, it is an essential embodiment of the protective helmet 30′ according to the invention that the supporting arms 54, 55 protruding laterally downwards are swept-forward and formed on the supporting cage in front of the longitudinal centre of the supporting cage 42. The force transmission points are thereby shifted further towards the front side relative to the points on which the supporting arms 54, 55 are integrally formed on the supporting cage 42 whereby the force transmission into the helmet shell 36 is improved for the purpose of its enhanced deformability. Like in the protective helmet 30 described in the beginning the supporting cage 42 is formed of a stiff, elastically flexible material. On this supporting cage the supporting arms 54, 55 and 56 protruding laterally downwards and backwards and downwards are integrally formed, i.e. they consist of the same material. The supporting cage 42 is provided with the peripherally closed supporting strip 148 at its lower edge on which the supporting arms 54, 55, 56 are integrally formed. The neck strap 46 is likewise attached to the supporting cage 42 and has two ends releasably connected by a tightening unit 48 accommodated in the clearance 60 as another helmet accessory in the neck area in the supporting cage 42 according to the
The chin strap 300 constitutes a part of the helmet accessories of the protective helmet 30′ according to the invention. The chin strap 300 has to be provided on a protective helmet used as a mountaineering or tree climbing helmet. Two chin strap fixation points 310 for the chin strap 300 are provided on the inside of the helmet shell 36 in front of the temple areas, 311 (
The chin strap 300 is lead backwards to the tightening unit 48 from the two front chin strap fixation points 310, 311, run through the supporting shell 172 of the tightening unit 48 on both sides, and finally joined in the rear chin strap fixation point 312. Under each temple area the chin strap is lead to a redirecting lug 320 or 330. From the redirecting lug 320, the chin strap 300 extends under the chin to the other redirecting lug 330. In this area under the chin the chin strap 300 is additionally provided with a size adjustment lug.
When a tensile force is applied to the chin strap 300 its rear end on the supporting arm 56 which is led through the supporting shell 174 is pulled obliquely forward. In this way the fixation of the helmet on the head is stabilised. As a result of the additional fixation of the supporting arm 56 on the inner side the helmet shell 36 above of the supporting arm 56 via the bridges 212, 214 the tensile force of the chin straps 300 is optimally absorbed at their rear end. In this way the supporting arm 56 is prevented from being pulled out of the snap-on connection to the helmet shell 36 at its free end. Therefore, not only the snap-on connection between the supporting arm 56 and the helmet shell 36 is stabilised, but also the position of the rear chin strap fixation point 312. In this way it is possible for the supporting arm 56 to take up about 50% of the entire load introduced, while the supporting arms protruding laterally downwards can take up approximately 25%, respectively.
The helmet shell 36 of the protective helmet is provided with ventilation openings 53 and guide slots 250, 252, 260, 262 for retaining elements or cams of the ventilation gate 50′ at least in an area following the snap-on connection point of the supporting arm 56 protruding backwards and downwards in the forward direction. The retaining elements of the ventilation gate 50′ comprise a pair of angle elements 258, 260 in its front section and a pair of resiliently deflectable retaining arms 254, 256 in its rear section. The angle elements 258, 260 and the retaining arms 254, 256 are shiftably and releasably retained in their associated guide slots 260, 262 or 250, 252 when the ventilation gate 50′ is mounted as can be seen in
30, 30′ protective helmet
32 face protection
34 ear protection
35
a ear protection capsule
35
b ear protection capsule
36 helmet shell
37
a supporting bracket
37
b supporting bracket
40 interior fitting subassembly
42 supporting cage
44 head band
46 neck strap
47
a support arm
47
b support arm
48 tightening unit
49 bolt
50, 50′ ventilation slide
51 hole
52 ventilation orifice
53 ventilation orifice
54 support arm
55 support arm
56 support arm
56
a protrusion
56
b protrusion
60 clearance
62 reinforcing rib
64 reinforcing rib
66 guiding slot
68 retainer knob
70 retainer knob
72 guiding slot
74
a rod-like protrusion
74
b rod-like protrusion
76 recess
78 slot
80 mounting device ear protection
80
a ear protection supporting point
80
b ear protection supporting point
84 mounting device face protection
84
a face protection supporting point
84
b face protection supporting point
85
a cam
85
b cam
92
a yoke spring
92
b yoke spring
132 visor
132
a retaining arm
132
b retaining arm
134
a ring bearing bushing
134
b ring bearing bushing
136
a connector
136
b connector
142 supporting strip
144 supporting strip
146
a connecting point
146
b connecting point
146
c connecting point
146
d connecting point
148 supporting strip
149 padding material
150 connecting strip
152 ribs
154 ribs
156 through-hole
157
a bifurcated end
157
b bifurcated end
158 through-hole
168 mount for supporting shell
169 transfer lever
170 joint
171 joint
172 supporting shell
173 joint
174 latch flap
176 orifices
178 slot
179 slot
180 piece of padding material
200 intermediate part
210 retaining part
211 retaining part
212 bridge
214 bridge
220 wall
222 wall
228 aperture
230 aperture
242 longitudinal axis
244 straight line
250 guide slot
252 guide slot
254 retaining arm
256 retaining arm
258 angle element
259 angle element
260 guide slot
262 guide slot
270 cams
272 cams
280 wall
282 wall
300 chin strap
310 chin strap fixation point
311 chin strap fixation point
312 chin strap fixation point
314 mounting lug
316 mounting lug
318 mounting lug
320 redirecting lug
330 redirecting lug
340 aperture
380 mounting device
α angle
β angle
Number | Date | Country | Kind |
---|---|---|---|
10 2012 000 370.6 | Jan 2012 | DE | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2012/076253 | 12/19/2012 | WO | 00 |