CN220936941U - Adjustable headband for a helmet and helmet provided with one such headband - Google Patents

Abstract

The utility model relates to an adjustable headband for a helmet comprising a strap (5) forming at least a part of a loop around the head of a user. The adjusting means (6) adjusts the circumference of the ring by moving one end of the strap (5) fixed to the attachment point (9), the attachment point (9) being movable relative to the body. The rotary actuator (10) is functionally connected to the adjustment device (6) by means of a transmission, such that rotation of the rotary actuator (10) results in a movement of the attachment point (9). The adjusting device (6) comprises a threaded section (11) and a nut (12). The nut (12) and the threaded section (11) form a screw connection, and rotation of the rotary actuator (10) causes the nut (12) to move along the threaded section (11). The nut (12) or the threaded section (11) moves along the longitudinal axis of the threaded section (11) and supports the attachment point (9). The utility model also relates to a helmet provided with such a headband.

Description

Adjustable headband for a helmet and helmet provided with one such headband

Technical Field

The present utility model relates to an adjustable headband for a helmet and a helmet provided with such a headband.

Background

In many fields, in particular mountain climbing and high-altitude work, it is common practice to use helmets. To improve ergonomics, helmets equipped with adjustable headbands are often used. Depending on the configuration, the circumference or shape of the headband may be adjustable. The headband takes the form of a ring whose circumference can be adjusted to fit the user's head.

The headband has one or two straps and an adjustment means for adjusting the overlap length between the straps or at the ends of the straps. Document EP0558427 describes a helmet provided with a headband in the form of a loop having a system for adjusting the circumference of the headband, said system being a rack system fixed to the crown. The rack system can adjust the circumference of the headband and also move the front and pillow portions of the headband relative to the crown. This solution is complex and expensive to implement. This embodiment is attractive but is tuned by a plurality of predefined recesses. The front portion of the headband and the rear portion of the headband may be differently adjusted.

It is also known to provide the adjustment means by means of a rope fixed to the crown. The cord is associated with a clip, such as a cotta cord clip (tanka cord clamp), that stretches the neck strap portion of the headband to adjust the circumference of the headband. Only the rear of the headband is adjustable.

Document US 2015/032767 discloses a protective helmet provided with a neck strap that can be deformed to fit the head size of the user.

It is apparent that the prior art arrangements are not always very practical and there is a need for improved headband arrangements.

Disclosure of utility model

It is an object of the present utility model to remedy these drawbacks, and more particularly to provide a headband that is easier to use than prior art arrangements, and in particular has better adjustment finesse.

These drawbacks are often overcome by the headgear of protective helmets for mountain climbing and high-altitude work, including:

-a loop designed to bypass the user's head;

-a first strip forming at least part of a loop;

-a first adjustment device configured to adjust the circumference of the ring by moving one end of the first strap, the first adjustment device having a first body designed to be fixed to the crown of the protective helmet;

-at least one first attachment point to which an end of the first strap is fixed, the first attachment point being movable relative to the first body to define a circumference of the ring;

A first rotary actuator functionally connected to the first adjustment means by means of a first transmission means, such that rotation of the first rotary actuator causes the first attachment point to move relative to the first body.

The head band is remarkable in that the first adjustment means comprises a first main thread section with a first thread and a first main nut, the first main nut and the first main thread section forming a screw connection, rotation of the first rotary actuator causing the first main nut to move along the first main thread section, at least one of the first main nut and the first main thread section to move along a longitudinal axis of the first main thread section and to support the first attachment point.

According to one feature of the utility model, the second strip forms at least a part of a loop. The first adjustment device has a first secondary threaded section with a second thread, a first secondary nut sliding along the first secondary threaded section, and one end of the second strap is secured to a first additional attachment point supported by one of the first secondary nut and the first secondary threaded section.

Preferably, the value of the first thread is different from the value of the second thread.

In a particular embodiment, the first main thread section belongs to a first screw and the second main thread section belongs to a second screw, the first screw and the second screw being functionally connected to the first rotary actuator by a first transmission or a second transmission such that rotation of the first rotary actuator causes rotation of the first screw and the second screw.

Advantageously, the first main flight section and the first secondary flight section belong to a single first screw.

In a specific embodiment, the main thread section is separated from the first secondary thread section by a connection region, on which the first transmission exerts a force to rotate the first screw.

Preferably, the headband comprises a second adjustment device configured to adjust the circumference of the loop, the second adjustment device being provided with a second main thread section and a second main nut having a first thread, the second main nut and the second main thread section forming a screw connection, at least one of the second main nut and the second main thread section being movable along a longitudinal axis of the second main thread section and supporting a second attachment point mounted movable relative to the body of the second adjustment device, the second attachment point being fixed to the other end of the first strap or to another strap, the second adjustment device being connected to the first rotary actuator or the second rotary actuator by a second transmission, rotation of the second rotary actuator causing the second main nut to move along the first main thread section.

It is a further object of the present utility model to provide a helmet comprising a headband according to any one of the preceding constructions and a crown to which the headband is fixed.

Advantageously, the first adjustment means are fixed to a lateral portion of the crown.

Drawings

Other advantages and features will become more apparent from the following description of specific embodiments and implementations of the utility model, given by way of non-limiting example only, and illustrated in the accompanying drawings, in which:

fig. 1 schematically shows a side view of a helmet;

FIG. 2 schematically illustrates a perspective view of a headband in accordance with one embodiment;

FIG. 3 schematically illustrates a bottom view of the headband illustrated in FIG. 2 without the rotary actuator;

FIG. 4 schematically illustrates a perspective view of the headband shown in FIG. 2 with two straps removed from the adjustment device;

FIG. 5 schematically illustrates an exploded view of the headband of FIG. 2;

Fig. 6 schematically illustrates an exploded view of another embodiment of an adjustment device for a headband.

Detailed Description

Fig. 1 shows a protective helmet 1 provided with a headband 2, the circumference of the headband 2 being adjustable. Figures 2, 3, 4 and 5 show a headband 2 having a loop whose circumference is adjustable.

The protective helmet 1 comprises a crown 3, which crown 3 is made of a material that prevents it from folding onto itself. The crown 3 may preferably be made of a plastic material, for example of injected polycarbonate or ABS or of polystyrene or of expanded polypropylene, or of any other plastic material, in particular of injected or thermoformed plastic or foam.

The crown 3 comprises a front portion 3a at the front (i.e. close to the forehead of the user) and a pillow portion 3b at the rear. The front portion 3a is separated from the pillow portion 3b by two side portions 3c, a right side portion 3c and a left side portion 3c, respectively. The protective helmet 1 is provided with a headband 2 having a front part and a rear part. The rear portion may be a neck strap 4. The headband 2 is secured to the crown 3 to form a loop designed to encircle the head of a user.

The headband 2 has one or more connectors for securing the headband 2 to the crown 3. The connection between the headband 2 and crown 3 may be detachable or non-detachable. The connectors may define a rigid or flexible connection between the headband 2 and the crown 3. The securing of the headband 2 to the crown 3 may be performed using only rigid connections, only flexible connections, or a mixture comprising one or more rigid connections and one or more flexible connections.

The headband 2 has at least a first strap 5 and at least a first adjustment means 6. The first strip 5 forms at least part of a loop. The first adjusting means 6 are used to adjust the circumference of the ring. The first strap 5 is designed to contact the head to press on the head and support the crown 3.

In the embodiment shown in fig. 2 to 6, the headband 2 has a first strap 5 and a second strap 7 and a first adjusting device 6 and a second adjusting device 8. The first adjusting means 6 and the second adjusting means 8 are configured to adjust the circumference of the ring.

The first adjusting means 6 and the second adjusting means 8 may or may not be operated independently, depending on the configuration. In one configuration, the first and second adjustment means 6, 8 may act on the front and rear portions of the ring during adjustment. Alternatively, one of the first and second adjustment means 6, 8 acts on the front part of the ring, while the other acts on the rear part of the ring. Depending on the configuration, the first adjusting means 6 and the second adjusting means 8 are operated simultaneously, or they are operated independently in time.

In one configuration a single strap is used and passed around the user's head together with the first adjustment means 6. The first adjusting means 6 are fixed to at least one end of the first strip 5. In another configuration, multiple strips are used, as shown two strips are used. The first adjustment means 6 move the first 5 and second 7 strips to change the circumference of the ring, if applicable. The ring may also be formed in part by the crown 3. For example, the front part of the ring is formed by a crown, and the first strip 5 forms the rear part of the ring. The opposite configuration is possible.

The first adjustment means 6 are used to adjust the circumference of the ring by moving one end of the first strap 5. The first end of the first strap 5 moves relative to the crown 3. The first adjustment means 6 have a first body designed to be fixed to the crown 3 of the protective helmet 1. The first body may be removable or non-removable with respect to the crown 3. The first body may be fixedly mounted on the crown 3 or may be slightly movable relative to the crown.

The headband 2 has a first attachment point 9 movably mounted with respect to the first body of the first adjustment device 6. The first attachment point 9 is mounted movable relative to the crown 3. The end of the first strap 5 is fixed to a first attachment point 9. The end of the first strap 5 may be detachably or non-detachably fitted with respect to the first attachment point 9. In the embodiment shown, the end of the first strip 5 defines a hole, preferably a through hole 5a. The first attachment point 9 is formed by a pin inserted into the hole to secure the first end of the first strap 5 to the first attachment point 9. An opposite configuration is possible in which the end of the first strap 5 has a pin and the first attachment point 9 defines a hole. Another system for fixing the end of the first strap 5 to the first attachment point 9 is possible.

In order to change the circumference of the ring, the headband 2 has a first rotary actuator 10, the first rotary actuator 10 being functionally connected to the first adjustment means 6 by means of a first transmission means, such that rotation of the first rotary actuator 10 causes the first attachment point 9 to move relative to the first body. The first rotary actuator 10 is actuated in rotation, i.e. it rotates about its rotation axis, and the rotation of the first rotary actuator 10 causes a movement of the first attachment point 9 and the end of the first strap 5 with respect to the first body and with respect to the crown 3 to increase or decrease the circumference of the ring.

In order to provide a continuous adjustment of the circumference of the ring so as to more easily match the exact circumference of the user's head, the first adjustment means 6 comprises a first main thread segment 11 with a first thread and a first main nut 12. The nut 12 and the first main thread section 11 form a screw connection. Rotation of the first rotary actuator 10 causes the first main nut 12 to move along the first main thread section 11 and vice versa. At least one of the first main nut 12 and the first main thread section 11 moves along the longitudinal axis of the first main thread section 11 and supports the first attachment point 9.

In the illustrated arrangement, the first attachment point 9 is fixedly mounted on the first main nut 12. Rotation of the first rotary actuator 10 causes rotation of the first main thread segment 11, resulting in movement of the first main nut 12 relative to the body along the longitudinal axis of the first main thread segment 11. In the particular embodiment shown, the first main thread section 11 is only rotationally movable about an axis of rotation corresponding to the longitudinal axis of the first main thread section 11. The first strap 5 is fixed to the first main nut 12 and rotation of the first rotary actuator 10 causes translation of the first attachment point 9.

In an alternative embodiment, the first attachment point 9 is mounted on the first main thread section 11. Rotation of the first rotary actuator 10 causes rotation of the first main nut 12, thereby rotating the first main thread segment 11. The first strip 5 is fixed to the first main thread section 11. Rotation of the first actuator 10 results in rotation of the first main nut 12 and translation of the first main thread segment 11. The first main thread segment 11 moves relative to the crown 3 in translation along the longitudinal axis of the first main thread segment 11.

Other more or less complex constructions with more or less large volumes are possible using at least the first main thread section 11 and the first main nut 12 to move the first attachment point 9 when the first rotary actuator 10 is rotated.

In the embodiment shown, the first rotary actuator 10 is mounted around a rotation axis 13 fixed to the first body of the first adjustment device 6. In an alternative embodiment, the first rotary actuator 10 is located at a distance from the first body. The first rotary actuator 10 is functionally connected to the screw connection by a first transmission comprising a flexible transmission shaft. The first transmission means may also be a cable or any other means for converting the torque exerted on the first rotary actuator into a force or torque on the first adjustment means 6.

It is particularly advantageous to use a screw connection between the first main nut 12 and the first main thread section 11 to adjust the circumference of the ring. Such a mechanical connection enables precise and continuous adjustment of the circumference of the ring. The screw connection enables the first main nut 12 to move relative to the first main thread section 11 and the position of the first main nut 12 relative to the first main thread section 11 to be maintained when a force is exerted on the first main nut 12 or the first main thread section 11. The first rotary actuator 10 is able to adjust the circumference of the ring, but the force exerted on the straps of the headband has little or no effect on the movement of the first main nut 12 relative to the first thread segments 11. The same mode of operation is obtained in an adjustable wrench that also uses a screw connection.

In the advantageous embodiment shown in fig. 2 to 5, the headband 2 has a second strap 7 forming at least part of a loop. The first adjusting device 6 has a first secondary thread segment 14 with a second thread. The first secondary nut 15 slides along the first secondary thread segment 14. One end of the second strap 7 is fixed to a first additional attachment point 16 supported by one of the first secondary nut 15 and the first secondary threaded section 14. The first adjusting device 6 has two threaded sections, a first main threaded section 11 and a first secondary threaded section 14, with two nuts 12 and 15 arranged to define two screw connections. The two screw connections are connected to two different points of the ring. In a preferred manner, the two screw connections enable the circumference of the ring to be varied at its front and rear to keep the helmet 1 centred with respect to the user's front mid-plane.

It is particularly advantageous that the first rotary actuator 20 is functionally connected to the first main screw connection and the first secondary screw connection. The first main screw connection is formed by a first main thread section 11 and a first main nut 12.

The first secondary screw connection is formed by a first secondary screw thread section 14 and a first secondary nut 15.

In a particular configuration, the first primary screw connection and the first secondary screw connection are mechanically connected by an additional transmission such that the first screw connection can be actuated simultaneously. Thus, rotation of the first rotary actuator 10 simultaneously actuates the first primary screw connection and the first secondary screw connection. In a preferred manner, the first main screw connection generates a first movement value of the first main attachment point 9 for a predetermined rotation of the first rotary actuator 10, which first attachment point 9 movement value is different from the movement value of the first additional attachment point 16.

This difference in movement length can be obtained by a difference in rotational speed of the first screw connection relative to the rotational speed of the second screw connection. In the embodiment shown in fig. 6, the additional transmission may be formed by a gear mechanism, at least a belt or any other equivalent means that introduces such a difference in rotational speed. Alternatively or additionally, the first main thread segment 11 has a first thread which is different from the second thread of the first secondary thread segment 14.

In another configuration, the first main thread segment 11 and the first secondary thread segment 14 are each independently connected to the first rotary actuator 10.

The use of two movable attachment points, namely a primary first attachment point 9 and a first additional attachment point 16 connected to both ends of two strips or a single strip, enables centering of the crown with respect to the anterior-medial plane for better control of the circumference of the different rings.

Preferably, the ratio between the first thread and the second thread maintains the front midplane of the head coincident with the front midplane of the helmet. It is advantageous to have a first thread that is larger than the second thread, so that one rotation of the first rotary actuator has a greater effect on the front of the ring than on the rear of the ring.

The first adjusting means 6 provided with the first main thread segment 11 and the first secondary thread segment 14 may be realized in different forms.

In a particular embodiment, the first main flight 11 belongs to a first screw and the first auxiliary flight 14 belongs to a second screw. In the illustrated configuration, the first and second screws are functionally connected to the first rotary actuator 10 such that rotation of the first rotary actuator 10 simultaneously results in rotation of the first and second screws. The first and second screws may be functionally connected to the first rotary actuator 10 by a first transmission or by a first and second transmission such that rotation of the first rotary actuator 10 results in rotation of the first screw and rotation of the second screw.

As shown in fig. 6, the first screw may be connected to the second screw by one or more gears such that the rotational speed between the first screw and the second screw is different for a given rotational speed of the first rotary actuator. One or more gears may be replaced with a belt or any other equivalent drive system. Alternatively or in combination, the first rotary actuator 10 is connected to the first screw via a first transmission, and the first rotary actuator 10 is connected to the second screw via a second transmission. The first transmission may be different from the second transmission to vary the rotational speed of the first screw relative to the second screw for a given rotational speed of the first rotary actuator 10.

In another embodiment, the first main flight segment 11 and the first secondary flight segment 14 belong to a single first screw.

In one embodiment, the first main thread section 11 is separated from the first secondary thread section 14 by a connection region 17. The first transmission exerts a force on the connection region 17 to rotate the first main thread segment 11 and the first secondary thread segment 14. In an advantageous configuration shown in fig. 5, the first transmission has a gear wheel which meshes with the first screw.

When the first rotary actuator 10 is firmly fixed to the first body of the first adjustment device 6, it is advantageous that the first rotary actuator 10 is in the form of a gear with a groove extending over the wheel periphery. The grooves engage with other grooves formed on the circumference of the first screw. Rotation of the first rotary actuator 10 causes rotation of the first screw. The grooves form the connection areas 17.

More generally, the first rotary actuator 10 is preferably connected to the first screw at a connection region 17 between the first main thread section 11 and the first secondary thread section 14. This configuration makes it easier to obtain a connection zone 17 that is substantially fixed with respect to the crown 3, i.e. it does not move in translation along the longitudinal axis of the screw.

In order to make the adjustment of the circumference of the ring easier, it is advantageous to use a first adjustment means 6 and a second adjustment means 8. The use of two adjustment means enables an increase in the adjustment amplitude of the circumference of the ring, preferably a doubling of the adjustment amplitude of the circumference.

Preferably, a second adjusting device 8 is used which is identical or substantially identical to the first adjusting device 6. The second adjustment means may assume one of a plurality of configurations as defined above. The structure of the second adjusting means 8 is independent of the structure of the first adjusting means 6.

In the embodiment shown, a second rotary actuator 18 is used, which is connected to the second adjusting device 8 via a second transmission.

The second adjusting means 8 are used to adjust the circumference of the ring. The second adjusting means 8 is provided with a second main thread section 19 with a first thread and a second main nut 20. The second main nut 20 and the second main thread section 19 form a screw connection. At least one of the second main nut 20 and the second main thread section 19 moves along the longitudinal axis of the second main thread section 19 and supports the second main attachment point. The second main attachment point is mounted movable relative to the second body of the second adjustment device 8. The second main attachment point is fixed to the other end of the first strap 5 or to the other strap 7. The second adjusting device 8 is connected to the first rotary actuator 10 or to the second rotary actuator 18 via a second transmission. Rotation of the first or second rotary actuator causes the second main nut 20 to move along the second main thread section 19.

Advantageously, the second adjusting means 8 have a second secondary threaded section 22 cooperating with a second secondary nut 23 to form a second secondary screw connection. The function of the screw connection is the same as the function of the first adjusting means 6 described above.

The second adjusting device 8 may have a single screw or two screws. The first strap 5 is fixed to the primary attachment point and the second strap 7 is fixed to the secondary attachment point. In the illustrated embodiment, the secondary attachment point is formed by two nuts, namely a second primary nut 20 and a second secondary nut 23.

It is advantageous to mount the first adjusting means 6 and the second adjusting means 8 as right adjusting means and left adjusting means. The use of the first adjustment means 6 and the second adjustment means 8 enables to increase the extent of the change of circumference and/or to reduce the volume of each adjustment means. It is thus easier to integrate the adjustment means within the volume delimited by the crown 3. It is easier to install the adjustment means in the thickness of the foam provided between the crown 3 and the user's head.

In a preferred manner, the first value of the first thread of the first adjusting means 6 is the same as the first value of the first thread of the second adjusting means 8. The same is preferable for the value of the second thread.

In the second adjusting device, the second main thread section 19 is separated from the second secondary thread section 22 of the second screw by a connection region 17, the connection region 17 being functionally connected with the second transmission device for actuation by the second rotary actuator 18.

In the embodiment shown, the first rotary actuator 10 is mounted to rotate about an axis of rotation that is perpendicular or substantially perpendicular to the wall of the crown 3 near its attachment point. This configuration enables the first rotary actuator 10 to be more easily integrated into the internal space of the helmet delimited by the crown 3. This arrangement makes it easier to adjust the circumference of the headband when the helmet is worn without changing the configuration of the crown 3.

In another embodiment, the first rotary actuator 10 is mounted to rotate about an axis of rotation that is parallel or substantially parallel to the wall of the crown 3 near its attachment point. It is advantageous to form a hole in the crown 3 to access the first rotary actuator 10 and rotate the first rotary actuator 10.

In the embodiment shown, each of the first adjustment means 6 and the second adjustment means 8 is directly fixed to the crown 3, and each of the first adjustment means 6 and the second adjustment means 8 defines a rotation axis 13 arranged in a fixed manner for the rotation of the first rotary actuator 10 and the second rotary actuator 18.

In a particular embodiment, the first rotary actuator 10 is connected to the first adjustment means 6 by a first transmission means and to the second adjustment means 8 by a second transmission means. The first and second transmissions transmit the torque of the first rotary actuator 10 to the first and second adjustment devices 6, 8.

In a particular embodiment, the first rotary actuator 10 is mounted at the rear of the crown 3 and is connected by first and second adjustment means to first and second adjustment means 6 and 8 mounted on the left and right sides of the crown 3. In an alternative embodiment, the first rotary actuator 10 is mounted on another part of the crown 3.

In the embodiment shown, the first body of the first adjusting means 6 and the second body of the second adjusting means 8 are formed by two shells 6a or 8a surrounding a screw or rod.

Fig. 6 shows an embodiment with two screws mechanically connected to each other by two gears such that the two screws rotate simultaneously. The embodiment of fig. 6 also shows actuation of both screws by the gear system 24.

In a preferred form, the headband 2 is provided with a neck strap 4, i.e. the rear of the loop mounted rotatably relative to the front of the loop. Advantageously, the rotation axis of the neck strap is formed by an attachment point so as to have a movable rotation axis moved by the first rotary actuator 10.

In the embodiment shown, each adjustment device has a body which is firmly fitted to the crown 3 by means of a connector defining a rigid connection.

Claims (5)

1. Headband (2) for a protective helmet (1), comprising:

-a loop designed to bypass the user's head;

-at least a first strip (5) forming at least part of a loop;

-a second strip (7) forming at least a portion of the loop;

-a first adjustment device (6) configured to adjust the circumference of the ring by moving one end of the first strap (5), the first adjustment device (6) having a first body designed to be fixed to the crown (3) of the protective helmet (1);

-at least a first attachment point (9), an end of the first strap (5) being fixed to the first attachment point (9), the first attachment point (9) being movable relative to the first body to define a circumference of the ring, the first adjustment device (6) being configured to move the first attachment point (9) to adjust the circumference of the ring;

-a first rotary actuator (10) functionally connected to the first adjustment means (6) by means of a first transmission means, such that rotation of the first rotary actuator (10) causes the first attachment point (9) to move relative to the first body;

Wherein the first adjusting device (6) comprises a first main thread section (11) with a first thread and a first main nut (12), the first main nut (12) and the first main thread section (11) forming a screw connection, rotation of the first rotary actuator (10) causing the first main nut (12) to move along the first main thread section (11), at least one of the first main nut (12) and the first main thread section (11) to move along a longitudinal axis of the first main thread section (11) and to support the first attachment point (9), and

Wherein the first adjusting device (6) has a first secondary threaded section (14) with a second thread, a first secondary nut (15) sliding along the first secondary threaded section (14), one end of the second strap (7) being fixed to a first additional attachment point (16), which first additional attachment point (16) is supported by one of the first secondary nut (15) and the first secondary threaded section (14),

Characterized in that the first main thread section (11) and the first auxiliary thread section (14) belong to a single first screw rod, and the first main thread section (11) is separated from the first auxiliary thread section (14) by a connection region (17), and the first transmission device exerts a force on the connection region (17) to rotate the first screw rod.

2. Headband (2) according to claim 1, characterized in that the value of the first thread is different from the value of the second thread.

3. Headband (2) according to claim 1, characterized in that it comprises a second adjustment device (8), the second adjustment device (8) being configured to adjust the circumference of the loop, the second adjustment device (8) being provided with a second main threaded section (19) with a first thread and a second main nut (20), the second main nut (20) and the second main threaded section (19) forming a screw connection, at least one of the second main nut (20) and the second main threaded section (19) being movable along the longitudinal axis of the second main threaded section (19) and supporting a second attachment point, the second attachment point being fitted movable relative to the body of the second adjustment device (8), the second attachment point being fixed to the other end of the first strap (5) or to the other strap (7), the second adjustment device (8) being connected to the first rotary actuator (10) or the second rotary actuator (18) by means of a second transmission, rotation of the second rotary actuator (18) causing the second main nut (20) to move along the second main threaded section (19).

4. Helmet (1), characterized by comprising a headband (2) according to claim 1 and a crown (3), the headband (2) being fixed to the crown (3).

5. Helmet (1) according to claim 4, characterized in that the first adjustment means (6) are fixed to the sides of the crown (3).