The invention relates to an ear protection to be fastened to a protective helmet, particularly for forestry workers, comprising two ear protectors each of which comprises: a fork-like supporting bracket on which an ear protection capsule is pivotably supported, a rotary plate jointedly connected to the supporting bracket in relation to which the supporting bracket is bistably tiltable into an extended and into a retracted position, and a receiving part attachable or attached to a helmet in which the rotary plate is rotatably supported and which is pivotable between an operating position and a parking position defined by stoppers.
Such an ear protection is known from the DE 10 2007 011 110 A1 which will be referred to in more detail further below.
A protective helmet comprising such an ear protection is known from the document DE 8714490 U1. The protective helmet is comprised of a helmet shell and 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 distance between the head and the helmet shell. The helmet has, at its outer circumference, a protrusion encompassing the lateral and the rear part of the helmet which is provided with four recesses for fastening the crossed strap and other recesses for fastening additional attachment elements at the lower edge. The additional attachment elements may be added or removed as required. At the broadest positions of the helmet a recess is provided on the outside of the protrusion encompassing the largest part of the helmet. This is the attachment position of, among other items, the ear protection. The ear protection is comprised of two ear protectors respectively comprising a wire bracket and an ear protection capsule. The ear protection is, together with a face protection, fixed to the outside of the helmet by means of a common connecting piece which is inserted into the protrusion. Disadvantageous in a helmet equipped like such is that, in use, obstacles the helmet passes engage behind the brackets of the ear protection capsules and, in this way, impair the wearer of the helmet on duty or may tear the helmet from his or her head and thereby endanger the wearer.
An ear protection known from the DE 10 2007 011 110 A1 already mentioned in the beginning comprises a device for attaching an ear protection capsule to the outside of a protective helmet. Here, a protective helmet is referred to in which the helmet design is, by default, customized so that two ear protectors can be releasably attached to the outside of the helmet at its edge on each side of the helmet above the position of the ear in a slot or the like provided in the helmet there. For this purpose, a receiving part or each ear protector is formed so that it can be fixed in the slot by means of a snap-on fastening. The ear protectors are worn in an operating position during work in which the ear protection capsules are in a retracted position in which they tightly abut the ears. The ear protectors can be moved into a standby position from the operating position if the ear protection is temporarily unnecessary. In this position, the ear protection capsules are located in an extended position in which they are still positioned above the ears, however, pivoted away from the ears to the outside. The ear protection capsules may also be retained in this position, for example, to enable a conversation during work. Finally, a break or parking position exists for the ear protectors. In the parking position, the ear protection capsules are pivoted upwards from the operating position towards the rear side and on the outside of the helmet. For the ear protection capsules to be movable past the edge of the helmet into the parking position, it is required to first bring the ear protectors into the standby position. Retaining each ear protection capsule in the extended or retracted position is rendered possible by a double-tongued leaf spring jointedly connecting the supporting bracket of the ear protection capsule to a rotary plate of the ear protector and having two bistable positions.
One problem to be solved by the known ear protection is seen in retaining the supporting bracket including the ear protection capsule in the parking position since the ear protection capsule, due to gravity, strives to rotate downwards and back into the standby position from the parking position. To prevent such a downwards rotation, it was common that the user pivots the supporting bracket to the inside in its parking position in which it is tilted upwards so that the bistable leaf spring presses the ear protection capsule to the helmet shell from the outside. In this way, relatively large forces were generated on the helmet, for example, at the mount of the supporting bracket on the helmet, which gave rise to the risk that the helmet and/or the supporting bracket were damaged. The known ear protection is therefore formed so that a safe positioning of each ear protection capsule in an upturned parking position outside of the helmet is effected. To this end, the receiving part comprises a projection protruding substantially parallel to the axis of rotation which restricts a movement of the rotary plate in a specific rotational position when abutting to the supporting bracket in the known ear protection. In the known ear protection, the solution of the problem is complicated by the use of a bistable leaf spring which is, indeed, supposed to render it possible that the supporting bracket, together with the ear protection capsule, occupies a defined extended or retracted posture in the operating or standby position, but, at the same time serves to jointedly connect the supporting bracket to the rotary plate and can therefore not have an exactly defined tilting point and cannot ensure a defined exertion of pressure on the ear by the ear protection capsule in case of different head sizes of helmet users. Since the jointed connection between the supporting bracket and the rotary plate is only established by the bistable leaf spring and depends on its two bistable end positions, the supporting bracket neither has an exactly defined extended position nor an exactly defined retracted position which impedes an adjustment of the ear protection to different head sizes.
The fixation of the ear protector in the parking position is effected with the aid of a stopper supported by the leaf spring abutting on a projection of the receiving part. However, this support is dependent on the friction of the leaf spring on the projection and may therefore change in the course of time. The force in the direction towards the operating position required on the rotary plate to move the mentioned stopper out of engagement may therefore decrease in the course of time so that the user might, nevertheless, attempt to prevent an undesired downwards rotation of the supporting bracket with the aid of the ear protection capsule by pivoting the ear protectors inwards on the outside of the helmet in the parking position so that the ear protection capsule is pressed against the helmet shell from the outside.
It is the object of the invention to design an ear protection of the type mentioned in the beginning so that the abovementioned problems are eliminated, i.e., in particular that the risk that a helmet may get caught on obstacles in use due to the ear protection attached to it and that an ear protector may unintentionally rotate back into the protecting position from the parking position is removed.
According to the invention, this object is solved by the supporting bracket and the rotary plate being connected to each other by a tilting joint, a tilting axis of which penetrates the supporting bracket and the rotary plate, by a yoke spring disposed adjacent to the tilting joint between the rotary plate and a free end of the supporting bracket pre-stressing the supporting bracket to abut on additional stoppers defining the extended and the retracted position to thereby effect its bistable tiltability and by the receiving part being designed for an attachment on the inside of a helmet.
According to the invention, the receiving part is mounted on the inside of a helmet so that the ear protection capsules and the associated supporting brackets are located substantially within the perimeter of the protective helmet. The helmet therefore does not offer any possibilities for obstacles such as branches and the like to get caught on its outside. If the ear protection is not required, the ear protectors may be rotated backwards into the parking position which is located within the helmet within the perimeter of the protective helmet.
Due to the attachment of the receiving part of each ear protector on the inside of the helmet, particularly on the inside of the helmet shell, in addition to the supporting brackets and the ear protection capsules, the receiving parts are also protected against an external exertion of a force by obstacles the helmet may contact. Furthermore, the supporting brackets are pivotable between the standby position and the parking position within a clearance between helmet shell and interior fittings due to the receiving parts being mounted on the inside of the helmet, i.e., they are always located within the perimeter of the helmet shell. Accordingly, the supporting bracket and the ear protection capsules do not offer any catching or engagement points for obstacles in either position.
Due to the fact that in each ear protector of the ear protection according to the invention the supporting bracket and the rotary plate are connected to each other by a tilting joint a tilting axis of which penetrates the supporting bracket and the rotary plate, the drawbacks resulting from a bistable leaf spring being used for jointedly connecting the supporting bracket to the rotary plate are eliminated. In the ear protection according to the invention, the tilting axis constitutes a defined centre of rotation which does not change in the course of time. Furthermore, according to the invention, the yoke spring being located adjacent to the tilting joint between the rotary plate and a free end of the supporting bracket and pre-stressing the supporting bracket only ensures the build-up of a force between the supporting bracket and the rotary plate, i.e., it does not simultaneously define the extended and the retracted position of the supporting bracket. These positions are rather determined by defined stoppers. The yoke spring only provides the force for moving the supporting bracket towards these stoppers. The yoke spring together with the other stoppers therefore establishes defined end positions for the supporting bracket when it is extended and retracted and thus ensures its bistable tiltability between defined stoppers.
In the ear protection according to the invention, the yoke spring does not have the function of a joint supporting the supporting bracket but only serves to build up a force with the aid of which the supporting bracket can be retained in a defined extended and in a defined retracted position on the additional stoppers. The problem of an undesired downward rotation of the ear protector from the parking position downwards in the direction of the standby position is strongly reduced if not eliminated by the ear protection according to the invention because the ear protection capsule will be positioned on the inside of the helmet and on the outside of interior fittings of the helmet in the parking position and will therefore have a substantially reduced tendency to rotate downwards from the parking position as a result of pressure from both sides.
Advantageous embodiments of the ear protection according to the invention constitute the subject matter of the subclaims.
In one embodiment of the ear protection according to the invention, an eccentric bolt for adjusting the initial load applied to the supporting bracket by the yoke spring is rotatably arranged in the rotary plate and in contact with the yoke spring. It is therefore possible to adjust the magnitude of the force with which the ear protection capsule is pressed against the ear in the retracted position of the supporting bracket in a simple manner.
In a further embodiment of the ear protection according to the invention, a slide pre-stressed in the direction towards the rotary plate by a pressure spring is shiftably supported at the free end of the supporting bracket, said slide comprising a retaining lug which can be brought in contact with a slide path on the receiving part and being prevented from being shifted in its retracted position and not being prevented from being shifted in its extended position by the supporting bracket and releasably retaining the supporting bracket in its parking position by means of an engagement in a recess in the slide path of the receiving part. The spring pre-stressed slide is, in this embodiment of the invention, retained in engagement with the rotary disk in a position in which the free end of the supporting bracket engages in a recess of the slide. The recess of the slide thus forms one of the additional stoppers defining the retracted position of the supporting bracket. On the other hand, the free end of the supporting bracket abuts to the rotary disk in a recess which consequently constitutes one of the other stoppers and defines the extended position of the supporting bracket. In this latter position, the slide is shiftable on the supporting bracket along the slide path on the receiving part in the direction opposite to the rotary plate against the force of the pressure spring so that the supporting bracket including the rotary plate can be pivoted in the receiving part and the supporting bracket including the ear protection capsule can be located in the parking position.
In a further embodiment of the ear protection according to the invention, a groove extending at least over a semi-circle for accommodating a circular arc-shaped shoulder of the rotary plate is formed in the receiving part. The rotary plate is guided in the receiving part during its rotation.
In a further embodiment of the ear protection according to the invention, a resilient tongue protruding from the receiving part engages in a complementary depression in the rotary plate for locking the mutual engagement of the receiving part and the rotary plate, and a push button for releasing the fixation is arranged in the rotary plate. The supporting bracket may, in this way, be locked in place by a snap-on fastening together with its rotary plate in the receiving part and released by operating the push button.
Embodiments of the invention will be described in more detail below with reference to the drawings in which:
A protective helmet designated by 30 in its entirety and comprising an ear protection 33 according to the invention which is designed, particularly for use in forestry, is shown in different views in
Three supporting arms formed as spacers of which only the supporting arms 54 and 55 can be seen in
A mounting device for the ear protection 33 comprises two receiving parts 80a, 80b attached to the inside of the helmet shell 36. The receiving parts 80a, 80b are pivot bearings for supporting brackets 37a, 37b together with the ear protection capsules 35a or 35b as described in more detail further below. The receiving parts 80a, 80b are respectively integrally formed on the inside of the helmet shell 36 as a bearing cup of the pivot bearings or, preferably, fixedly mounted as additional parts.
The ear protection 33 will now be described in more detail with reference to the drawings, particularly to
The two ear protectors 34a, 34b comprise the two ear protection capsules 35a, 35b which are pivotably supported in the fork-like supporting bracket 37a or 37b, respectively. The inside of the helmet shell 36 is provided with the fixedly attached receiving parts 80a, 80b. In the receiving parts 80a, 80b, the supporting brackets 37a, 37b are rotatably supported with rotary plates 39a or 39b jointedly attached to their free ends as can be seen in
Each supporting bracket 37a, 37b is designed so as to be spring pre-stressed 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 pivoted away from the ear in the non-bent position of each supporting bracket 37a, 37b, respectively, as shown in
In addition, each receiving part 80a, 80b and each supporting bracket 37a, 37b including the rotary plate 39a, 39b are formed so that the supporting bracket can only be pivoted backwards from the position shown in
According to the representation in
In the standby position of the ear protector 34a,b shown in
The pivotability and non-pivotability of the rotary plate 39a,b are determined by a slide 98a,b shown in a sectional view in
In the receiving part 80a,b, a groove 85a,b is formed which extends over at least a semi-circle and serves to accommodate a circular arc-shaped shoulder 49a,b of the rotary plate 39a,b as can be seen in
Each ear protection capsule 35a,b is concavely curved in the longitudinal direction on its side facing the ear so that it can more readily adjust to the shape of the ear and the head. This results in an improved pressure distribution on the ear and enables a better closure against the entry of noise in combination with a reduced application of pressure.
Number | Date | Country | Kind |
---|---|---|---|
102010026997.2 | Jul 2010 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP2011/061882 | 7/12/2011 | WO | 00 | 2/21/2013 |