DK202170623A1

DK202170623A1 - A noise suppressor for a firearm

Info

Publication number: DK202170623A1
Application number: DKPA202170623A
Authority: DK
Inventors: Lund Thomas; Hagstrøm Christen; Due Jensen Niels
Original assignee: Due Jensen Niels
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2023-08-31
Also published as: DK181359B1; WO2023110046A1

Abstract

The present invention relates to a noise suppressor for a firearm, the noise suppressor is monolithic and comprises a casing and a number of baffles arranged within said interior of the casing to divide said interior into a number of chambers, each of said baffles comprising a projectile opening positioned and dimensioned to allow said projectile to go through in its way from the entry opening and to the exit opening. A shield is provided enclosing at least a part of the casing, said shield comprising one or more coherent structures having a plurality of through going openings and being connected to an outer surface of the casing by one or more connecting members extending between an inner surface of the shield and an outer surface of the casing thereby providing a distance between the inner surface of the shield and the outer surface of the casing.

Description

DK 2021 70623 A1 1

A NOISE SUPPRESSOR FOR A FIREARM

FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION

Noise suppressors, sometime also referred to as silencers, for a firearm are often heavy due to being designed with an aim to being durable. As a noise suppressor is arranged at the mouth of a barrel, the weight distribution of the firearm with noise suppressor often becomes less attractive for the user.

Further, gasses leaving the mouth of a barrel in relation to firing a projectile are hot, resulting in that after firing relatively few rounds with the firearm, the noise suppressor becomes so warm that it poses a safety risk e.g. burning a user accidentally touching the silencer. In addition, a relative high mass of a noise suppressor may delay the point in time, where its temperature reaches a safety limit due to the specific heat capacity of the material from which the noise suppressor is made, but also prolongs the time it takes before it is cooled down.

Hence, an improved noise suppressor would be advantageous, and, in particular, a noise suppressor of low weight and/or a noise suppressor mitigating the problems with respect to heating of the noise suppressor would be advantageous.

DK 2021 70623 A1 2

OBJECT OF THE INVENTION

It is an object to the invention to provide a noise suppressor having low weight and/or a noise suppressor mitigating the problems with respect to heating of the noise suppressor.

It is a further object of the present invention to provide an alternative to the prior art.

SUMMARY OF THE INVENTION

Thus, the above-described object and several other objects are intended to be obtained in a first aspect of the invention by providing a noise suppressor for a firearm, the noise suppressor is monolithic and comprises e a casing having an interior, said casing having an entry opening at a first end of the casing for entry of a projectile and an exit opening at a second end of the casing for exit of said projectile; e a number of baffles arranged within said interior of the casing to divide said interior into a number of chambers, each of said baffles comprising a projectile opening positioned and dimensioned to allow said projectile to go through in its way from the entry opening and to the exit opening.

A noise suppressor as disclosed herein refers to a device that reduces the noise created by firing a firearm. By this, a noise suppressor according to the present invention does not make the firing totally silent, but reduces the noise compared to the noise emitted with no noise suppressor equipped.

A shield is preferably provided enclosing at least a part of the casing, said shield comprising one or more coherent structures having a plurality of through going openings and being connected to an outer surface of the casing by one or more connecting members extending between an inner surface of the shield and an outer surface of the casing, thereby providing a distance between the inner surface of the shield and the outer surface of the casing, wherein a total cross sectional area of the one or more connecting members evaluated at the outer surface of the casing is less than 10% of the total area of the outer surface of the casing enclosed by the shield.

DK 2021 70623 A1 3

By preferred embodiments of the invention the heat transfer from the casing to the surroundings are mostly heat radiation and since the shield comprises a plurality of through going openings, allowing the radiated heat to effectively be absorbed by the surroundings, the result is a noise suppressor for most uses, which can be handled without the risk of serious burns, since the temperature of the shield does not reach a temperature where a human may burn his skin.

Besides suppressing noise created by the firearm, the suppressor has also shown to reduce the recoil from a shot. In some preferred embodiments, where baffles are curved, the reduction of recoil is found to be even higher than for e.g. baffles being non-curved.

Further embodiments are presented in the following as well as in the appended claims.

BRIEF DESCRIPTION OF THE FIGURES

The present invention and in particular preferred embodiments thereof will now be disclosed with reference to the accompanying figures. The figures show ways of implementing the present invention and are not to be construed as being limiting to other possible embodiments falling within the scope of the attached claim set.

Figure 1 illustrates a first embodiment according to the invention; the embodiment is shown in a number of views including end views, side views and cross sectional views.

Figure 2 illustrates a second embodiment according the invention; the embodiment is shown only in cross sectional view similar to the cross sectional view of fig. 1 (the dimensions indicated are examples not limiting the scope of the invention).

Figure 3 illustrates a third embodiment according to the invention; the embodiment is shown in a side view and in a cross sectional view.

DK 2021 70623 A1 4

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[1] Reference is made to fig. 1 illustrating a noise suppressor 1 for a firearm according to a first embodiment of the invention. The noise suppressor is monolithic which is preferably to be understood as the various elements making up the noise suppressor not being assembled post production, but provided during the production, in a material addition process such as 3D-printing.

In the illustrated embodiment, the noise suppressor comprising a casing 2 having an interior 3. As most clearly seen in the cross sectional view of fig. 1, the casing has entry opening 4 at a first end 5 of the casing 2. This entry opening is provided for entry of a projectile. As will become apparent from the below, the illustrated embodiment has a tubular section 16 having a thread for co-operation of a thread provided on a barrel, so that the noise suppressor is arranged on the barrel by screwing the noise suppressor unto the barrel with a section of the barrel extending into the tubular section 16, thereby placing the mouth of the barrel at the entry opening 4.

The casing 2 also has an exit opening 6 for exit of a projectile and the exit opening 6 is provided at a second end 7 of the casing.

Suppression of the shot sound is at least partially provided by a number of baffles 8, which are arranged longitudinally distributed, as illustrated, within the interior of the casing 2. These baffles extend across the longitudinal direction of the noise suppressor and divide the interior 3 into a number of chambers 9. In the embodiment illustrated, seven baffles 8 are providing eight chambers 9, but the invention is not limited to seven baffles as another number of baffles 8 may be provided.

To allow for a projectile passage from entry opening 4 to exit opening 6, each of the baffles 8 has a projectile opening 10 positioned and dimensioned to allow said projectile to go through in its way from the entry opening 4 and to the exit opening 6.

The baffles are preferably rotationally symmetric around an axis passing through the center of the projectile opening. As can be seen in fig. 1, the casing and the

DK 2021 70623 A1 baffles are in the illustrated embodiment rotationally symmetric around an axis passing through the centre of the entry opening 4 and the exit opening 6, but asymmetric configurations are considered to be within the scope of the present invention. 5

The noise suppressor comprising a shield 11 enclosing at least a part of the casing 2. In the illustrated embodiment in fig. 1, the shield 11 encloses the casing 2 in full, except from the ends, but a shield 11 only enclosing for instance a mid- section or one or more end sections, are also considered to be within the scope of the invention.

As illustrated, the shield comprising a coherent structure having a plurality of through going openings 12. In other embodiments, the shield comprising more than one coherent structure e.g. by the shield only encasing first end 5 and the second end 7, leaving a middle section with no shield 11.

The shield 11 is connected to an outer surface of the casing 2 by one or more connecting members 19 extending between an inner surface of the shield 11 and an outer surface of the casing 2, thereby providing a distance d between the inner surface of the shield 11 and the outer surface of the casing 2.

During use of the noise suppressor, heat produced inside the casing and to minimize the amount of heat being transferred to the shield by heat conduction, which heat conduction occur mainly through the material of the connecting members 13, the total cross sectional area of the one or more connecting members 19 evaluated at the outer surface of the casing 2 is preferably less than 10% of the total area of the outer surface of the casing 2 enclosed by the shield 11. By this, the shield may be seen as being thermic isolated from the casing, whereby the outer surface of the shield 11 does not get so warm that a human would be burned by touching the shield 11. This effect is pronounced by distance d between the inner surface of the shield and the outer surface of the casing 2, as the void thereby created contains air that also acts as an insulator. Thus, without being bound by theory, the heat transfer from the casing to the surroundings are mostly heat radiation and since the shield comprising a plurality of through going openings, allowing the radiated heat to effectively be absorbed by the

DK 2021 70623 A1 6 surroundings, the result is a noise suppressor that for most uses can be handled without the risk of serious burns.

[2] In preferred embodiments of the noise suppressor, the total area of the through going openings 12 occupies at least 50% of the total area of the shield 11. By total area of the shield is preferably meant the area of the shield including the openings and may be evaluated as

Y=" Area of opening (i)

Total area of shield including hte area of the openings

In other embodiments, the through going openings occupy at least 75%, such as at least 80% and preferably less than 95% of the total area of the shield 11. By such large area occupied by the openings, the radiation of heat to the surroundings may occur effectively thereby contributing to an efficient cooling of the casing 2.

[3] The distance d (see fig. 1 detail D) between the inner surface of the shield 11 and the outer surface of the casing is preferably larger than 0.5 mm, such as larger than 1.0 mm, such as larger than 2.0 mm, such as larger than 3.0 mm and smaller than 5.0 mm. By this, the air in-between the outer surface of the casing 2 and the inner surface of the shield may provide a heat insulation thereby at least contributing to decreasing heat being transferred to the shield 11.

[4] The shield will represent some heat capacity being able to store energy in form of heat. Such a heat capacity governed by at least two factors, namely the specific heat capacity Cp (J kg"? K?) for the material from which the shield is made and the total mass of the shield. To keep the total mass of the shield 11 low and thereby its heat capacity low, the shield is preferably given a substantial uniform thickness being larger than 0.5 mm, such as larger than 1.0 mm, such as larger than 2.0 mm and smaller than 4.0 mm. Providing the shield with a thickness larger than 1.0 mm further more incorporates a safety function into the shield 11, namely that it may function as a device preventing fractures from the casing 2 or from the interior component to be spread to the surroundings, as the shield may catch such fractures. Such fractures may originate from e.g. a projectile unintendedly hitting e.g. one of the baffles 8. It is noted that the size and shape

DK 2021 70623 A1 7 of the through going openings 12 in the shield may be shaped also to catch fractures of a certain size.

[5] In the illustrated embodiment of fig. 1 and 2, the through going openings 12 are uniformly arranged in the shield 11, but may be arranged differently, either based on physical considerations as discussed above and/or even based on creating a certain aesthetic appearance. [6] For instance the shape of the through going openings may be rectangular, circular, square, rhombus, parallelogram, elliptical, triangular, kite, trapezoid, pentagonal, hexagonal or octagonal, or other shapes not mentioned.

[7] As the shield 11 is connected to the casing by the connecting members 19 as disclosed herein, the shield 11 may be subjected to being bend inwardly towards the casing 2, when e.g. being handled and/or transported. While the material of the shield may be selected with a suitable elasticity to allow for such bending it may be preferred to limit the amount of bending e.g. to avoid fatigue of the material and/or plastic deformations of the shield 11. To this, the shield 11 may be provided with a number of protrusions 13 (see fig. 1 detail D)) extending from an inner surface of the shield 11 towards an outer surface of the casing 2, leaving a clearance between a distal end 14 and the inner outer surface of the casing 2.

Alternatively or in combination, the outer surface of the casing may be provided with such protrusions 14 extending from the outer surface of the casing towards the inner surface of the shield leaving a clearance between the distal end 14 and the inner surface of the shield 11.

The distal end 14 being opposite to a proximal end from which the protrusions 13 extend from said inner surface of the shield 11 or from the outer surface of the casing 2. By such protrusions 13, the displacement of the shield towards the casing is limited by the amount of the clearance in the regions of the shield, where the protrusion is provided. The clearance between the the distal end 14 of protrusion and the outer surface of the casing 2 or inner surface of the shield 11 may be less than 1/10'" of the distance d between the inner surface of the shield 11 and outer surface of the casing 2. [8] In preferred embodiments, the protrusions 13 may taper in the direction towards the casing 2 as illustrated in fig. 1, detail D) or may taper in the direction towards the inner surface of the shield

DK 2021 70623 A1 8 11 in embodiments where the protrusions 13 extend from the casing towards the shield 11.

[9] In the illustrated embodiment of fig. 1, the shield 11 is connected by the connecting members 19 to the outer surface of the casing 2 only at the first end 5 and at the second end 7 and has a number of protrusions 13 uniformly distributed along the shield 11.

[10] In the illustrated embodiment of fig. 2, the shield 11 is connected by a plurality of connecting members 19 to the outer surface of the casing 2 and no protrusions 13 are provided although such protrusions 13 may be provided. The plurality of connecting members 19 are distributed evenly between the first end 5 and the second end 7.

[11] It is often beneficial to place weight of a firearm as close as possible to the handle of the firearm to avoid introducing too much weight at the end of a barrel.

Although noise suppressors according to the present invention may be manufactured with a relatively low weight, preferred embodiments may comprise a tubular section 16 extending, in an longitudinal direction of the noise suppressor, a distance inwardly from the first end 5 so as to define a cavity configured for receiving an end of a barrel of a firearm with the entry opening 4 positioned at the internal end of the tubular section 16. By this, the noise suppressor may be placed with its centre of gravity closer to the handle of the firearm.

[12] To attach the noise suppressor 1 to a barrel of a firearm, the noise suppressor may further comprise a thread 17 typically provided at the first end 5.

Such a thread is configured to co-operate with a thread provided at the end of a barrel of a firearm, so as to arrange the noise suppressor on the barrel by a screwing action. In embodiments, where the noise suppressor is made by an additive material process such as 3D-printing, the thread may be provided during the additive material process and optionally refined afterwards or cut afterwards.

[13] In the embodiments disclosed in figures, the thread 17 is provided at the internal end of the tubular section 16.

DK 2021 70623 A1 9

[14] Preferred embodiments are designed with the aim of keeping the total weight of the noise suppressor low and by this reducing the wall thickness of the elements of the noise suppressor in particular the thickness of the casing 2 and the thickness of the baffles 8. In order to achieve a low weight, it may be beneficial to the structural strength of the noise suppressor to provide support elements internally in the noise suppressor. To this, some embodiments may comprise a number of radial support struts 15a as illustrated in e.g. fig. 1. As seen from the figures, these radial support struts extend between the tubular section 16 and interior surface of the casing 2 with a radial component. By radial component is typically meant that the strut have a component in the radial direction (from centre towards casing), when projected onto the radial direction.

[15] Another way to increase the structural strength of the noise suppressor is to provide a number of longitudinal support struts 15b extending with a longitudinal component in the longitudinal direction between a first baffle 8 and the tubular section 16 as illustrated in the figures. The first baffle 8 is the one being closest to the entry opening 4. By a component in the longitudinal direction is typically meant that the strut have a component in the direction (longitudinal direction of the noise suppressor), when projected onto the longitudinal direction. While it may be preferred to provide both the longitudinal and the radial struts 15a, 15b, one of them may be omitted.

[16] Another measure to increase the structural integrity of the noise suppressor, which may be used together with the radial support struts 15a and the longitudinal support struts 15b, is to provide longitudinal support struts (15b) extending between a first baffle 8 and an adjacent second baffle 8, where the first baffle 8 is the one closest to the entry opening 4 and the adjacent baffle is the one next to the first baffle in the direction towards the exit opening 6. Further longitudinal struts 15b extending between the second baffle 8 and an adjacent third baffle 8 may also be provided. This is illustrated in figs. 1-3.

While use of such supports 15a, 15b do indeed provide a structural integrity and allows for reduction of the wall thickness of the casing 2 and the baffles 8, the baffles which due to the suppressor being monolithic are made integral with the

DK 2021 70623 A1 10 casing 2 provide a good structural integrity of the suppressor as the casing 2 and the baffles support each other. Further, in embodiments as the one illustrated in fig. 1, the region where the baffles proceed into the casing is curved in a manner so that stress concentration is less prone, which may be accomplished by the second derivative of the generatrix being close to zero.

[17] Without being bound by theory, it is suggested by the present invention that a noise suppressor having a chamber 9 with different volumes provides a more efficient suppression of noise and possibly also recoil. In preferred embodiments of the invention, this has been utilized by designing the noise suppressor with the volume of the chambers decreasing from chamber to chamber in a direction from the first 5 end to the second end 7.

[18] In preferred embodiments, the cross sectional areas of projectile openings 10 are increasing in the direction from the first 5 end to the second end 7, such as to provide a conical projectile opening. By this, the projectile opening may be made relatively narrow close to the mouth of the barrel and at the same time be relatively wide at the exit opening 6. By this a distortion between centre line of the barrel and centre line of the noise suppressor may be allowed, which may reduce the high manufacturing precision demand for e.g. attachment of the noise suppressor to the barrel, which in turn may reduce the manufacturing costs for the noise suppressor.

[19] It has been found in connection with the present invention that while baffles being a general flat member can suppress noise, it may be beneficial to used baffles 8, which are curved. In the illustrated embodiments, all of the baffles 8 are curved and essentially rotational symmetric around a longitudinal axis (centre axis) of the noise suppressor. However, some of the baffles 8 may be shaped differently. The illustrated baffles 8 have a curve shape wherein the generatrix of a cross sectional view of a baffle 8 proceed from the projectile opening 10 of the baffle towards the inner wall of the casing in concave shape with the cavity of the concave shape facing the first end 5. By this the baffles have been given a form, which is believed to fertilise creation of gas motion having a torus like a vortex structure, since the flow of gases is directed by the curved shaped producing a vortex.

DK 2021 70623 A1 11

It is suggested, that producing such a vortex may reduce the magnitude of the recoil, as the curved shape of the baffles will provide a thrust reversing in a fluid dynamical smooth manner.

Further, the curved shape of the baffles in combination with the connections to the casing are also found to strengthen the structural integrity as the baffles 8 and the casing 2 structurally support each other.

[20] Although not illustrated, one or more such as all baffles 8 may have penetration to allow fluid to pass through the surface of the baffles 8.

[21] Noise suppressors according to preferred embodiments of the invention may be designed to depart from having a casing, which are cylindrically shaped from end to end. In the illustrated embodiments, the outer shape of the casing 2 and the shield are both tapered towards first end 2 and the second end 7 and being cylindrically shaped in between the taperings, or being substantially ellipsoid.

Besides from serving a technical purpose, this also opens up for designing the suppressor to have a certain aesthetic design.

[22] It is often desirable to provide information on a noise suppressor to e.g. identify the noise suppressor and/or the owner. To this, the shield may comprise an outwardly facing labelling section 18 (cf. fig. 1) having an area configured to hold information, such as identification information, such as a serial number, logo, name, wherein said information is provided so as to allow a human to read the identification number by the naked eye. In preferred embodiments, such information is preferably provided during manufacturing of the noise suppressor.

[23] It may be relevant for e.g. the user and/or the manufacturer of the noise suppressor to monitor certain parameters related to the use of the noise suppressor and to this the noise suppressor may comprise one or more electronic elements embedded in the noise suppressor. Such electronic elements may be a data collecting element, collecting data pertaining to the operation of the noise suppressor during use, such as speed of the projectile, temperature of the noise suppressor, g-actions on the noise suppressor. Other electronic elements, such as

DK 2021 70623 A1 12 a clock device logging the time a shot is fired, a counting device counting the total number of shots either after a re-set and/or the total number of shots fired since first-time use of the suppressor, an accelerometer determining the amount of vertical displacement of the suppressor when a shot is fired, typically determined when a projectile passes through the suppressor.

The suppressor may also be equipped with a camera at the exit opening of the suppressor and having a field of view including an expected target position for the projectile.

To power the electronic elements, a battery such as a rechargeable battery, or capacitor may be embedded in the noise suppressor. In case of a rechargeable battery or capacitor, inductive charging may be applied so that physical access to the battery or capacitor is not needed.

[24] Electrical power may also be provided by embedding a linear generator. Such a linear generator may be powered by the pressure build up in the gas in the suppressor during a shot and/or through the recoil motion.

Embedded is to be understood in broad terms preferably to mean one or more cavities in which the electronic elements are placed. The cavity/cavities may or may not be accessible from the outside of the suppressor.

By embedding the electronic elements in the suppressor, heat either generated by the electronic elements or transferred to the electronic elements will be transferred to the surroundings as disclosed in the above with reference to the shield and reduction of heat transfer to the shield by conduction.

To access the data collected, a transmission element such as a wireless transmission or wired transmission for transmitting collected data to a receiver is typically provided.

[25] While a noise suppressor according to the present invention may be made by virtually any material, which can provide sufficient strength and allow the noise suppressor to be monolithic, it is often preferred to produce the noise suppressor

DK 2021 70623 A1 13 from titanium or a fibre reinforced composite. [26] Preferably, a noise suppressor to the invention may be manufactured by an additive manufacturing process such as 3D-printing.

Fig. 3 illustrates in a cross sectional, a third embodiment according to the invention. The embodiment comprising the same feature as the first embodiment shown in fig. 1, but no shield has been provided. A noise suppressor with no shield is also considered within the scope of the invention.

Although the present invention has been described in connection with the specified embodiments, it should not be construed as being in any way limited to the presented examples. The scope of the present invention is set out by the accompanying claim set. In the context of the claims, the terms “comprising” or “comprises” do not exclude other possible elements or steps. Also, the mentioning of references such as “a” or “an” etc. should not be construed as excluding a plurality. The use of reference signs in the claims with respect to elements indicated in the figures shall also not be construed as limiting the scope of the invention. Furthermore, individual features mentioned in different claims, may possibly be advantageously combined, and the mentioning of these features in different claims does not exclude that a combination of features is not possible and advantageous.

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List of reference symbols used: 1 Noise suppressor 2 Casing 3 Interior 4 Entry opening 5 First end 6 exit opening 7 Second end 8 Baffle 9 Chamber 10 Projectile opening (in baffle) — preferably circular 11 Shield 12 Through going opening 13 Protrusion 14 Distal end 15a Radial support strut 15b Longitudinal support strut 16 Tubular section 17 Thread 18 Labelling section 19 Connecting member d Distance

Claims

DK 2021 70623 A1 15 CLAIMS

1. A noise suppressor (1) for a firearm, the noise suppressor is monolithic and comprises e a casing (2) having an interior (3), said casing having an entry opening (4) at a first end (5) of the casing (2) for entry of a projectile and an exit opening (6) at a second end (7) of the casing (2) for exit of said projectile; e a number of baffles (8) arranged within said interior of the casing (2) to divide said interior (3) into a number of chambers (9), each of said baffles (8) comprising a projectile opening (10) positioned and dimensioned to allow said projectile to go through in its way from the entry opening (4) and to the exit opening (6); e a shield (11) enclosing at least a part of the casing (2), said shield comprising one or more coherent structures having a plurality of through going openings (12) and being connected to an outer surface of the casing (2) by one or more connecting members (19) extending between an inner surface of the shield (11) and an outer surface of the casing (2) thereby providing a distance (d) between the inner surface of the shield (11) and the outer surface of the casing (2), wherein a total cross sectional area of the one or more connecting members (19) evaluated at the outer surface of the casing (2) is less than 10%, such as less than 7%, such as less than 5% of the total area of the outer surface of the casing (2) enclosed by the shield (11).

2. A noise suppressor (1) according to claim 1, wherein the total area of the through going openings (12) occupy at least 50% of the total area of the shield (11), such as at least 75%, preferably at least 80% and less than 95% of the total area of the shield (11).

3. A noise suppressor (1) according to claim 1 or 2, wherein said distance (d) between the inner surface of the shield (1) and the outer surface of the casing is larger than 0.5 mm, such as larger than 1.0 mm, such as larger than 2.0 mm, such as larger than 3.0 mm and smaller than 5.0 mm.

4. A noise suppressor according to any one of the preceding claims, wherein said shield has a substantial uniform thickness, said thickness being larger than 0.5

DK 2021 70623 A1 16 mm, such as larger than 1.0 mm, such as larger than 2.0 mm and smaller than

4.0 mm.

5. A noise suppressor according to any one of the preceding claims, wherein the through going openings (12) are uniformly arranged in the shield (11).

6. A noise suppressor according to any one of the preceding claims, wherein the shape of the through going openings is rectangular, circular, square, rhombus, parallelogram, elliptical, triangular, kite, trapezoid, pentagonal, hexagonal or octagonal.

7. A noise suppressor (1) according to any one of the preceding claims, wherein the shield (11) comprising a number of protrusions (13) extending from an inner surface of the shield (11) towards an outer surface of the casing (2) leaving a clearance between a distal end (14) of each of said protrusions (13) and the inner outer surface of the casing (2), and/or the casing (2) comprising a number of protrusions (13) extending from the outer surface of the casing (2) towards the inner surface of the shield (11) leaving a clearance between a distal end (14) of each of said protrusion and the inner surface of the shield (11), where said distal end (14) being opposite to a proximal end from which the protrusions (13) extend either from said inner surface of the shield (11) or from said outer surface of the casing (2).

8. A noise suppressor (1) according to claim 7, wherein the said protrusions (13) are tapering in the direction towards the casing (2) when extending from the inner surface of the shield (11) towards the casing (2) and are tapering in the direction towards the shield (11) when extending from the casing (2) towards the shield (11).

9. A noise suppressor according to any one of the preceding claims, where the shield (11) is connected by the connecting members (19) to the outer surface of the casing (2), preferably only, at the first end (5) and at the second end (7).

10. A noise suppressor according to any one of the preceding claims, where the shield (11) is connected by a plurality of connecting members (19) to the outer

DK 2021 70623 A1 17 surface of the casing (2), wherein said plurality of connecting members (19) being distributed, preferably evenly, between the first end (5) and the second end (7).

11. A noise suppressor (1) according to any one of the preceding claims, further comprising a tubular section (16) extending, in an longitudinal direction of the suppressor, a distance inwardly from the first end (5) so as to define a cavity configured for receiving an end of a barrel of a firearm with the entry opening (4) positioned at the internal end of the tubular section (16).

12. A noise suppressor (1) according to any one of the preceding claims, further comprising a thread (17) provided at the first end (5) said thread being configured to co-operate with a thread provided at the end of a barrel of a firearm so as to arrange the noise suppressor on the barrel by a screwing action.

13. A noise suppressor according to claim 12, when dependant on claim 11, wherein said thread (17) is provided at the internal end of the tubular section (16).

14. A noise suppressor according to any one of the preceding claims 11-13, further comprising a number of radial support struts (15a) extending with a radial component between the tubular section (16) and an interior surface of the casing.

15. A noise suppressor according to any one of the preceding claims 11-14, further comprising a number of longitudinal support struts (15b) extending with a longitudinal component in the longitudinal direction between a first baffle (8) and the tubular section (16), said first baffle (8) being the one closest to the entry opening (4).

16. A noise suppressor according to any one of the preceding claims, further comprising longitudinal support struts (15b) extending between a first baffle (8) and an adjacent second baffle (8), said first baffle (8) being the one closest to the entry opening (4), and preferably also further longitudinal struts (15b) extending between said second baffle (8) and an adjacent third baffle (8).

DK 2021 70623 A1 18

17. A noise suppressor according to any one of the preceding claims, wherein the volume of the chambers is decreasing from chamber to chamber in a direction from the first (5) end to the second end (7).

18. A noise suppressor according to any one of the preceding claims, wherein the cross sectional areas of projectile openings (10) are increasing in the direction from the first (5) end to the second end (7), preferably to provide a conical projectile opening.

19. A noise suppressor according to any one of the preceding claims, wherein one or more such as all of the baffles (8) are curved and essentially rotational symmetric around a longitudinal axis of the noise suppressor, wherein the generatrix of a cross sectional view of a baffle (8) proceed from the projectile opening (10) of the baffle towards the inner wall of the casing in concave shape with the cavity of the concave shape facing the first end (5).

20. A noise suppressor according to any one of the preceding claims, wherein one or more such as all baffles (8) comprising penetration to allow fluid to pass through the surface of the baffles (8).

21. A noise suppressor according to any one of the preceding claims, wherein the outer shape of the casing (2) and the shield both are tapered towards first end (2) and the second end (7) and being cylindrically shaped in between the taperings, or being substantially ellipsoid.

22. A noise suppressor according to any one of the preceding claims, wherein the shield comprising an outwardly facing labelling section (18) having an area configured to hold information, such as identification information, such as a serial number, logo, name, wherein said information is provided so as to allow a human to read the identification number by the naked eye, where said information preferably is provided during manufacturing of the noise suppressor.

23. A noise suppressor according to any one of the preceding clams, wherein the noise suppressor comprising one or more electronic elements embedded in the noise suppressor, said electronic elements comprising a data collecting element

DK 2021 70623 A1 19 collecting data pertaining to the operation of the noise suppressor during use, such as speed of the projectile, temperature of the noise suppressor, g-actions on the noise suppressor, a clock device logging the time a shot is fired, a counting device counting the total number of shots either during a re-set and/or the total number of shots fired since first-time use of the suppressor, an accelerometer determining the amount of vertical displacement of the suppressor when a shot is fired, typically determined when a projectile passes through the suppressor, a camera at the exit opening of the suppressor and having a field of view including an expected target position for the projectile, a battery such as a rechargeable battery, or capacitor and a transmission element, such as a wireless transmission or wired transmission, for transmitting collected data to a receiver.

24. A suppressor according to any one of the preceding claims further comprising a linear generator configured to be powered by gas pressure build-up and/or recoil motion.

25. A noise suppressor according to any one of the preceding claims, wherein the noise suppressor is made from titanium or a fibre reinforced composite.

26. A noise suppressor according to any one of the preceding claims, wherein the noise suppressor is manufactured by an additive manufacturing process such as 3D-printing.