FI20225514A1 - Pressure controlling structure and method for controlling pressure - Google Patents

Abstract

The disclosure relates to a pressure controlling structure (1) comprising a first wall (2) extending from an inlet opening (3) at least in a first direction (4) and at least partly defining a first space (5) extending in a direction parallel to the first direction (4); at least one first opening (6) provided in the first wall (2), the first opening (6) having a first cross-sectional area, and the first opening (6) connecting the first space (5) to a second space (7), which second space (7) is provided on the opposite side of the first wall (2) in relation to the first space (5); at least two first side walls (8) extending from the first wall (2) in a direction angled in relation to the first wall (2); a second wall (9) extending between the two first side walls (8); and at least two second openings (10), each of the second openings having a second cross-sectional area, and the second openings (10) connecting the second space (7) to a third space (11), which third space (11) is provided on the opposite side of the second wall (9) in relation to the second space (7). The number of the second openings (10) is larger than the number of the first openings (6), the second cross-sectional area of each second opening (10) is smaller than the first cross-sectional area of each first opening (6), and a combined cross-sectional area of all the second openings (10) is larger than a combined cross-sectional area of all the first openings (6).

Description

PRESSURE CONTROLLING STRUCTURE AND METHOD FOR CONTROLLING

PRESSURE

BACKGROUND

The present disclosure relates to controlling propagation of pressure within a structure, and more particularly to a pressure controlling structure and a method for controlling pressure.

Pressure needs to propagate within a structure in many kinds of applications. If this takes place in an uncontrolled and non-optimal manner, it may cause unexpected and non- desirable side effects. These side effects may comprise for instance sounds and even affect functionality of the object.

An example of pressure propagating in a structure are high-temperature and high-pressure propellant gases escaping and escaping from a muzzle of a firearm, which can generate a shockwave that produces a loud muzzle blast.

Known solutions typically aim at slowing down the pressure propagation and using plate- like structures often provided in a direction transverse to the main direction of movement of the pressure to reflect sound waves to dampen them. More particularly, traditional silencers, also known as sound suppressors, suppressors, or sound moderators, are muzzle devices that reduce the acoustic intensity of the muzzle report by modulating the speed and pressure of the propellant gas from the muzzle and, hence, suppressing the muzzle blast. This, however, does not enable optimal prevention of non-desirable sounds, and slowing down the pressure wave typically causes structures heating up and similar effects accelerating the wear of the parts, especially the edges of the structure, for example.

N BRIEF DESCRIPTION OF THE DISCLOSURE

S 25 An object of the present disclosure is to provide a new pressure controlling structure and

O method for controlling pressure. 2 The object of the disclosure is achieved by a method and pressure controlling structure

E which are characterized by what is stated in the independent claims. Some embodiments 3 of the disclosure are disclosed in the dependent claims. io 30 The disclosure is based on the idea of controlling propagation of pressure within a structure

N such that the pressure is dispersed by walls and openings provided in the structure in a

N direction radial in relation to the inlet direction of the pressure.

An advantage of the method and structure of the disclosure is that undesired sound waves and interference of pressure waves within the structure can be reduced. Thus, the sounds caused by the pressure waves can be minimized and the pressure can be guided to move in an optimal way within the structure.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the disclosure will be described in greater detail by means of preferred embodiments with reference to the accompanying drawings, in which

Figure 1 illustrates schematically a pressure controlling structure according to an embodiment;

Figure 2 illustrates schematically a pressure controlling structure according to an embodiment in a cross-sectional side view;

Figure 3 illustrates schematically the pressure controlling structure of Figure 2 seen in the direction D-D;

Figure 4 illustrates schematically the pressure controlling structure of Figure 2 seen in the direction E-E;

Figure 5 illustrates schematically a pressure controlling device according to an embodiment; and

Figure 6 illustrates a method for controlling pressure.

The figures are provided for illustrating some features of the disclosure only and are not shown to scale. Same reference numbers are used for similar features in different figures and embodiments. Not all similar features are necessarily provided with reference numbers for the sake of clarity.

N

& DETAILED DESCRIPTION OF THE DISCLOSURE © The disclosure relates to controlling propagation of pressure within a structure, and more oS o 25 particularly to a pressure controlling structure and a method for controlling pressure.

I According to an embodiment, the pressure controlled in the pressure controlling structure

Za + and/or in the method for controlling pressure may comprise a shockwave. According to an = embodiment, the shockwave may comprise a shockwave generated by a controlled

N explosion or another type of a pressure source. A shockwave comprises a propagating

S 30 disturbance that moves faster than the local speed of sound in the medium. Such a supersonic shockwave, or supersonic pressure wave, breaks the sound barrier, causing a sound. A shockwave carries energy and can propagate through a medium. A shockwave is typically abrupt, nearly discontinuous, change in pressure, temperature and/or density of the medium. While the pressure controlling structure and the method are particularly suitable in connection with controlling such shockwaves, they are also applicable for controlling a more continuous pressure propagations and pressure waves in other types of applications.

Figure 1 illustrates schematically a pressure controlling structure according to an embodiment, Figure 2 illustrates schematically a pressure controlling structure according to an embodiment in a cross-sectional side view, Figure 3 illustrates schematically the pressure controlling structure of Figure 2 seen in the direction D-D, and Figure 4 illustrates schematically the pressure controlling structure of Figure 2 seen in the direction E-E.

Pressure controlling structures 1, such as the pressure controlling structures 1 of Figures 1-4, may be used in different kinds of applications, where pressure is configured to led or propagated through the structures. Such pressure controlling structures 1 may be particularly beneficial in applications, in which sound wave or interfering reflections of pressure should be avoided. According to an embodiment, the pressure may comprise a shockwave, and controlling the shockwave may comprise dissipating the shockwave.

It should be understood that the primary purpose of the pressure controlling structure 1 may be controlling and guiding the movement of pressure, such as a shockwave, inside the structure, but that is not necessarily the case. It should also be understood that the pressure controlling structures of the attached figures only illustrate the basic principles and certain embodiments of a pressure controlling structure 1 of the disclosure, and that the details of the pressure controlling structure may, thus, vary in different embodiments.

A pressure controlling structure 1, such as a pressure controlling structure 1 of at least one

N of the Figures 1-4, comprises a first wall 2 extending from an inlet opening 3 at least in a

O 25 first direction 4 and at least partly defining a first space 5 extending in a direction parallel

O to the first direction 4. = The inlet opening 3 refers to the opening, through which the pressure is configured to be > received in the pressure controlling structure 1. The pressure may, thus, be configured to

E enter the pressure controlling structure 1 through the inlet opening 3. According to an

N 30 embodiment, such as the embodiment of Figure 1, the first wall 2 may be curved in at least

LO one direction, preferably curved about a direction parallel with the first direction 4.

N According to an embodiment, such as the embodiment of Figure 1, the first wall 2 may s comprise a round cross section. The round cross section may comprise an annular shape, for example. According to another embodiment, the first wall 2 may comprise a cross section that forms a part of a round or annular shape, whereby multiple pressure controlling structures 1 may be brought together to form the round or annular first wall 2.

The first direction 4 may comprise a direction perpendicular to a plane defined by the inlet opening 3. The first direction 4 may also comprise a main direction of movement of the pressure. It other words, the pressure may exit the pressure controlling structure 1 at an end opposite to the inlet opening 3.

According to an embodiment, the one or more first walls 2 form a continuous first space 5 extending from a first end 25 of the pressure controlling structure 1 to the other of the pressure controlling structure 1, which is opposite to the first end 25. According to an embodiment, the first space 5 defined by one or more first walls 2 has a cylindrical shape.

According to an embodiment, the first space 5 has a cylindrical shape and the longitudinal direction of the first space 5 extends in the first direction 4 or in a direction parallel to the first direction 4.

The pressure controlling structure 1 further comprises at least one first opening 6 provided in the first wall 2, the first opening 6 having a first cross-sectional area, and the first opening 6 connecting the first space 5 to a second space 7. The second space 7 is provided on the opposite side of the first wall 2 in relation to the first space 5. In other words, the first wall 2 extends between the first space 5 and the second space 7 and separates the first space 5 from the second space 7. The at least one first opening 6, thus, connect the first space 5 to the second space 7. Thereby, the at least one first opening 6 enables the pressure being released from the first space 5 to the second space 7. According to an embodiment, the at least one first opening 6 enables the pressure being released from the first space 5 to the second space 7 in a radial direction 23. According to an embodiment, the pressure controlling structure 1 may comprise two or more first openings 6.

N 25 The pressure controlling structure 1 further comprises at least two first side walls 8

N extending from the first wall 2 in a direction angled in relation to the first wall 2. According <Q to an embodiment, the at least two first side walls 8 extend from the first wall 2 in a direction = radial and/or perpendicular in relation to the first wall 2. According to an embodiment, the

E at least two first side walls 8 extend from the first wall 2 in a direction perpendicular in + 30 relation to the first direction 4.

LO The pressure controlling structure 1 further comprises a second wall 9 extending between

N two first side walls 8. According to an embodiment, such as the embodiment of Figure 1, s the second wall 9 may be curved in at least one direction, preferably curved about a direction parallel with the first direction 4. According to an embodiment, such as the embodiment of Figure 1, the second wall 9 may comprise a round cross section. The round cross section may comprise an annular shape, for example. According to another embodiment, the second wall 9 may comprise a cross section that forms a part of a round or annular shape, whereby multiple pressure controlling structures 1 may be brought 5 together to form the round or annular second wall 9.

At least two of the first side walls 8 may, thus, be connected to the first wall 2 at one end and to the second wall 9 at the opposite end of the first side wall 8. According to an embodiment comprising more than two first side walls 8, each one of the first side walls 8 may be connected to the first wall 2 at one end and/or to the second wall 9 at the opposite end of the first side wall 8. According to another embodiment comprising more than two first side walls 8, two of the first side walls 8 may be connected, in each case, to the first wall 2 at one end and/or to the second wall 9 at the opposite end of the first side wall 8.

According to a further embodiment comprising more than two first side walls 8 and also comprising more than one first walls 2 and/or second walls, at least two of the first side walls 8 may be connected to a same first wall 2 at one end and/or to a same second wall 9 at the opposite end of the first side wall 8.

The pressure controlling structure 1 further comprises at least two second openings 10, each of the second openings 10 having a second cross-sectional area, and the second openings 10 connecting the second space 7 to a third space 11. The third space 11 is provided on the opposite side of the second wall 9 in relation to the second space 7. In other words, the second wall 9 extends between the second space 7 and the third space 11 and separates the second space 7 from the third space 11. The at least two second openings 10, thus, connect the second space 7 to the third space 11. Thereby, the at least two second openings 10 enable the pressure being released from the second space 7 to

N 25 the third space 11. According to an embodiment, the at least two second openings 10

S enable the pressure being released from the second space 7 to the third space 11 in a

O radial direction 23. According to an embodiment, the pressure controlling structure 1 may

O comprise three or more second openings 10.

E In the pressure controlling structure 1, the number of the second openings 10 is larger than 3 30 the number of the first openings 6, the second cross-sectional area of each second n opening 10 is smaller than the first cross-sectional area of each first opening 6, and a

N combined cross-sectional area of all the second openings 10 is larger than a combined

S cross-sectional area of all the first openings 6. According to an embodiment, the volume of the second space 7 may be larger than the volume of the first space 5. According to an embodiment, the volume of the third space 11 may be larger than the volume of the second space 7. In more general terms, according to an embodiment, the volume of an outer space may, in each case, be larger than a space inner compared to the outer space.

An advantage of such embodiments is that they enable controlling the propagation, or movement, of the pressure in such a manner that the pressure is released from the first space 5 through the second space 7 to the third space 11, while sound waves are, at least mostly, kept in the spaces closer to the first space 5. As the combined cross-sectional area of the outer openings, such as the second openings 10, is larger than the combined cross- sectional area of the inner opening(s), such as the first opening(s) 6, the pressure tends to propagate towards the larger combiner cross-sectional area. As the cross-sectional area of each one of the outer openings, such as the second openings 10, is smaller than the cross-sectional area of each one of the inner opening(s), such as the first opening(s) 6, the velocity of the pressure flow increases.

According to an embodiment, the pressure controlling structure 1 may further comprise at least two second side walls 12 extending from the second wall 9 in a direction angled in relation to the second wall 9; a third wall 13 extending between the two second side walls 12; and at least three third openings 14, each of the third openings having a third cross- sectional area, and the third openings 14 connecting the third space 11 to a fourth space 15, which fourth space 15 is provided on the opposite side of the third wall 13 in relation to the third space 11. The number of the third openings 14 may be larger than the number of the second openings 10. The third cross-sectional area of each third opening 14 may be smaller than the second cross-sectional area of each second opening 10, and a combined cross-sectional area of all the third openings 14 may be larger than a combined cross-sectional area of all the second openings 10.

According to an embodiment, the at least two second side walls 12 may extend from the

N 25 second wall 9 in a direction radial and/or perpendicular in relation to the second wall 9.

N According to an embodiment, the at least two second side walls 12 extend from the second

S wall 9 in a direction perpendicular in relation to the first direction 4. = According to an embodiment, such as the embodiment of Figure 1, the third wall 13 may

E be curved in at least one direction, preferably curved about a direction parallel with the first + 30 direction 4. According to an embodiment, such as the embodiment of Figure 1, the third io wall 13 may comprise a round cross section. The round cross section may comprise an

N annular shape, for example. According to another embodiment, the third wall 13 may

N comprise a cross section that forms a part of a round or annular shape, whereby multiple pressure controlling structures 1 may be brought together to form the round or annular third wall 13.

According to an embodiment, at least two of the second side walls 12 may, thus, be connected to the second wall 9 at one end and to the third wall 13 at the opposite end of the second side wall 12. According to an embodiment comprising more than two second side walls 12, each one of the second side walls 12 may be connected to the second wall 9 at one end and/or to the third wall 13 at the opposite end of the second side wall 12.

According to another embodiment comprising more than two second side walls 12, two of the second side walls 12 may be connected, in each case, to the second wall 9 at one end and/or to the third wall 13 at the opposite end of the second side wall 12. According to a further embodiment comprising more than two second side walls 12 and also comprising more than one second walls 9 and/or third walls 13, at least two of the second side walls 12 may be connected to a same second wall 9 at one end and/or to a same third wall 13 at the opposite end of the second side wall 12.

According to an embodiment, the volume of the third space 11 may be larger than the volume of the second space 7.

According to an embodiment, the pressure controlling structure 1 may further comprise at least one first dividing wall 16 extending from the first wall 2 in a direction angled in relation to the first wall on the side of the first wall opposite to the first space 5 and also extending in a direction parallel to the first direction 4. According to an embodiment, the at least one first dividing wall 16 may extend from the first wall 2 in a direction radial in relation to the first wall 2. In an embodiment, where the first wall 2 and the second wall 9 comprise an annular shape, the first dividing wall(s) 16 may, thus, split the second space 7 into segments.

According to an embodiment, the pressure controlling structure may further comprise at least one second dividing wall 17 extending from the second wall 9 in a direction angled

N 25 in relation to the second wall on the side of the second wall opposite to the second space

N 7 and also extending in a direction parallel to the first direction 4. According to an

S embodiment, the at least one second dividing wall 17 may extend from the second wall 9 2 in a direction radial in relation to the second wall 9. In an embodiment, where the second

E wall 9 and the third wall 13 comprise an annular shape, the second dividing wall(s) 17 may, 3 30 thus, split the third space 11 into segments. io According to an embodiment, the first wall 2, the two first side walls 8 and the second wall

N 9 may define the second space 7 and/or the second wall 9, the two second side walls 12

N and the third wall 13 may define the third space 11.

According to an embodiment, the first wall 2, the two first side walls 8, the at least one first dividing wall 16 and the second wall 9 may define the second space 7 and/or the second wall 9, the two second side walls 12, the at least one second dividing wall 17 and the third wall 13 define the third space 11.

According to an embodiment, at least one of the walls 2, 8, 9, 12, 13, 16, 17 may be provided with at least one protrusion 18 protruding in the first space 5, the second space 7, the third space 11 and/or the fourth space 15 to further control waves of the pressure.

According to an embodiment, at least one of the walls 2, 8, 9, 12, 13, 16, 17 may be shaped to form at least one protrusion 18 protruding in the first space 5, the second space 7, the third space 11 and/or the fourth space 15 to further control waves of the pressure. In other words, the protrusion(s) 18 may comprises separate shapes protruding to one of the spaces 5, 7, 11, 15 from the corresponding wall 2, 8, 9, 12, 13, 16, 17, or at least one of the walls 2, 8, 9, 12, 13, 16, 17 may itself be shaped to form the protrusion(s) 18. Such shapes may comprise for instance spikes, waves, indentation, or the like.

According to an embodiment, the pressure controlling structure 1 may be formed of at least two sections 19 split in a direction parallel to the first direction 4, such as in the embodiment of Figure 5. According to other embodiments, the pressure controlling structure 1 may comprise four, six, eight or twelve sections 19. Embodiments comprising multiple sections 19 may be beneficial for instance from cleaning and maintaining point of view. According to an embodiment, each section 19 may comprise at least one first dividing wall 16.

According to an embodiment, the pressure controlling device 1 may be formed of at least two parts 20 split in a direction transverse to the first direction 4, wherein each part 20 comprises at least one first side wall 8. According to an embodiment, each part 20 may comprise two or more first side walls 8 forming two or more second spaces 7 adjacent to

N 25 each other in the first direction 4 in the part 20.

N According to an embodiment, at least one of the sections 19 and/or parts 20 may be formed

YT as a separate structural part. According to another embodiment, the pressure controlling - structure 1 may be formed as one uniform structural part. t According to an embodiment, one or more third dividing walls 21 may be provided in an

N 30 outermost space 11, 21 to divide the outermost space into two or more space sections.

E According to an embodiment, in the area of at least a part 20 of the pressure controlling

S structure 1 closest to a first end 25 of the pressure controlling structure 1 provided with the inlet end 3, the first space 5 may be connected to an outermost space 11, 21 via openings 6, 10, 14, and in the area of at least a part 20 of the pressure controlling structure 1 closest to an end opposite to the first end 25 in the first direction 4, the first space 5 may not be connected to the outermost space via openings 6, 10, 14.

According to an embodiment, the pressure controlling structure 1 may comprise further spaces (not shown) provided between the first space 5 and an outermost space, such as a third space 11 or a fourth space 15.

According to an embodiment, at least the first openings 6 and the second openings 10 may be spread evenly along the 360 degrees circumference surrounding the first space 5 and the second space 7 in such a manner that pressure provided in the first space 5 can be dispersed evenly outwards from the first space 5. According to an embodiment, the first cross-sectional area of each first opening 6 may be smaller than the cross-sectional area of the first space 5, and the combined cross-sectional area of all the first openings 6 along the 360 degrees circumference and provided, in each case, between two adjacent first side walls 8 in the first direction 4 is larger than the cross-sectional area of the first space 5. An advantage of such embodiments is that the velocity of the pressure flow, such as the shockwave, may be accelerated, especially in the radial direction 23, simultaneously as the pressure, especially the pressure in the first space 5, is decreased. This may be particularly beneficial in connection with embodiments, where an object, such as a projectile, is configured to move in the first space 5 in the first direction 4, because the pressure behind the object, and preferably also before the object, in the first direction may be dissipated, or dispersed, in the radial direction 23, thus reducing interference to the movement of the object, and accelerates the velocity of the pressure flow, especially in the outermost space. This may further enhance the dispersion and dissipation of the pressure from the first space 5, especially behind the object in relation to the direction of movement of the object, as the object moves forward in the first direction 4 in the first space 5 from

N 25 one first side wall 8 to the next first side wall 8. This is because the moving object may

S expose a new group of first openings 6 behind the object each time the object passes a

O first side wall 8. In other words, as the object reaches a first side wall 8, a connection may o be formed from the first space 5 through a further group of first openings 6 between the > object and the inlet opening 3, namely the first openings 6 provided between the last i. 30 passed first side wall 8 and the previous passed first side wall 8, towards the second space = 7 and radially outwards from there through further openings 10, 14.

N According to an embodiment, the pressure controlling structure 1 may comprise a metal

S material, such as titanium, steel or aluminium or an alloy thereof, a ceramic material or a plastic material, such as a polymeric material. These materials may be particularly beneficial in connection with embodiments where high pressured and/or temperatures are involved, such as in embodiments related to guns or similar, whereas also other materials may be suitable in other embodiments and applications.

Although the cross-sections and circumferences may comprise a round shape, as shown in Figures 1, 3, 4 and 5, for example, in some embodiments, the walls, spaces and/or other structures may comprise a different shape. Preferably, the shape, round, or other shape, is configured to extend 360 degrees around the first space 5.

Figure 5 illustrates schematically a pressure controlling device according to an embodiment. According to an embodiment, a pressure controlling device 30, such as a pressure controlling device of Figure 5, may comprise a pressure controlling structure 1 according to an embodiment or a combination of embodiments described in this disclosure.

Depending on the embodiment, the pressure controlling device 30 may further have other structural parts, such as a distal end cap 31, a housing 32, a dividing sleeve 33, and a proximal end cap 34.

According to an embodiment, the pressure controlling device 30 may comprise a sound dampening device for an exhaust pipe of a vehicle, a catalytic converter of a vehicle, a ventilation device, a pneumatic drill, or similar device, in which a controlled explosion or a pressure source may cause a shockwave. In such embodiments, a pressure controlling structure 1, a pressure controlling device 30 and/or a method for controlling pressure according to an embodiment or a combination of embodiments disclosed in this description may be (configured to be) used to dampen sound caused by shockwave(s).

According to another embodiment, such as the embodiment of Figure 5, the pressure controlling device 30 may preferably comprise a sound dampening device for a gun, such as a firearm. In such embodiments, a pressure controlling structure 1, a pressure

N controlling device 30 and/or a method for controlling pressure according to an embodiment

N 25 or a combination of embodiments disclosed in this description may be (configured to be)

N used to dampen sound caused by shockwave(s). = More particularly, the pressure controlling structure 1, the pressure controlling device 30 > and/or the method for controlling pressure may be (configured to be) used for dissipating & a shockwave caused by a controlled explosion or a pressure source. Preferably the

N 30 shockwave is dissipated to all directions perpendicular to the first direction 4, in other

LO words radially in relation to the first direction 4. The shockwave is, thus, dissipated to

N spread evenly along the 360 degrees, such as towards the 360 degrees circumference s surrounding the first space 5 and the second space 7.

According to an embodiment, in which the pressure controlling structure 1 may be configured to be used in a connection of a gun or the pressure controlling device 30 comprises a sound dampening device for a gun, the pressure controlling structure 1 or the pressure controlling device 30 may form a silencer, a sound suppressors, a suppressor, or a sound moderator for a gun, or a part of one. The pressure controlling structure 1, the pressure controlling device 30 and/or the method for controlling pressure may be particularly beneficial in such embodiments, because the pressure controlling structures 1, as described in this disclosure, are configured to enable dissipation of pressure, such as a shockwave, after entering the pressure controlling structure 1 through the inlet opening 3, radially in relation to the first direction 4. This, together with the structure(s) of the pressure controlling structure 1 according to an embodiment or a combination of embodiments disclosed in this description enables the pressure, such as the shockwave, to be directed to the outer circumference of the pressure controlling structure, such as to the outermost space 11, 21. Thereby, when a projectile (not shown), such as a bullet, is pushed to the first space 5 via the inlet opening 3 and forward inside the first space 5, by the pressure, such as the shockwave, the pressure is, thus, dissipated to the outermost space and forward in the first direction 4 inside the outermost space. Thereby the pressure does not bypass the projectile in the first space 5, before the projectile exits the end of the pressure controlling structure 1 opposite to the first end 25. This has the further advantage that the pressure dissipated does not interfere with the projectile, whereby optimal accuracy and flight dynamics of the projectile can be achieved.

According to an embodiment, such as the embodiment of Figure 5, the pressure controlling device 30 may comprise a dividing sleeve 33. The dividing sleeve 33 may be configured to extend over the area of at least a part 20 of the pressure controlling structure 1 closest «N 25 to an end opposite to the first end 25 in the first direction 4. Thereby, a space may be

O formed between the dividing sleeve 33 and a housing 32 in the area of the at least one

O part 20 of the pressure controlling structure 1 closest to an end opposite to the first end 25 = in the first direction 4, into which the first space 5 may not be connected in the area of the

T at least one part 20 of the pressure controlling structure 1 closest to an end opposite to

E 30 the first end 25, but into which the first space 5 is connected to via openings 6, 10, 14 at < least in the area of at least one part 20 of the pressure controlling structure 1 closest to io the first end 25. This may be particularly beneficial, as the pressure is typically at its highest

N at the point it enters the first space 5 at the inlet opening 3. According to an embodiment,

N this space closest to the housing 32 may form the outermost space. The dividing sleeve 33 may comprise radial protrusions dividing the outermost space into segments, which are preferably arranged symmetrically and equally along the outermost space.

Figure 6 illustrates a method for controlling pressure. A method for controlling pressure, such as the method of Figure 6, comprises controlling 61 pressure by a pressure controlling structure 1 according to an embodiment or a combination of embodiments disclosed in this disclosure, or a pressure controlling device 30 described in this disclosure.

According to an embodiment, the method comprises dampening a sound caused by a pressure entering the pressure controlling structure 1 in the first direction 4 through an inlet opening 3 provided at a first end 25 of the pressure controlling structure 1 by dispersing the pressure from a first space outwards in a radial direction 23.

It is obvious for a person skilled in the art that, as the technology advances, the concept of this disclosure may be implemented in various ways. The disclosed solution and its embodiments are not limited to the examples described in this description but may vary within the scope of the claims.

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Claims (23)

1. A pressure controlling structure, characterized in that the pressure controlling structure comprises a first wall extending from an inlet opening at least in a first direction and at least partly defining a first space extending in a direction parallel to the first direction; at least one first opening provided in the first wall, the first opening having a first cross- sectional area, and the first opening connecting the first space to a second space, which second space is provided on the opposite side of the first wall in relation to the first space; at least two first side walls extending from the first wall in a direction angled in relation to the first wall; a second wall extending between the two first side walls; and at least two second openings, each of the second openings having a second cross- sectional area, and the second openings connecting the second space to a third space, which third space is provided on the opposite side of the second wall in relation to the second space; wherein the number of the second openings is larger than the number of the first openings, the second cross-sectional area of each second opening is smaller than the first cross-sectional area of each first opening, and a combined cross-sectional area of all the second openings is larger than a combined cross-sectional area of all the first openings.

2. Apressure controlling structure according to claim 1, wherein the pressure controlling structure further comprises N at least two second side walls extending from the second wall in a direction angled in N 25 relation to the second wall; N a third wall extending between the two second side walls; and <? at least three third openings, each of the third openings having a third cross-sectional - area, and the third openings connecting the third space to a fourth space, which fourth E space is provided on the opposite side of the third wall in relation to the third space; + 30 wherein the number of the third openings is larger than the number of the second io openings, the third cross-sectional area of each third opening is smaller than the N second cross-sectional area of each second opening, and a combined cross-sectional N area of all the third openings is larger than a combined cross-sectional area of all the second openings.

3. A pressure controlling structure according to claim 2, wherein the volume of the third space is larger than the volume of the second space.

4. A pressure controlling structure according to any one of claims 1-3, wherein the pressure controlling structure further comprises at least one first dividing wall extending from the first wall in a direction angled in relation to the first wall on the side of the first wall opposite to the first space and also extending in a direction parallel to the first direction.

5. A pressure controlling structure according to any one of claims 1-4, wherein the pressure controlling structure further comprises at least one second dividing wall extending from the second wall in a direction angled in relation to the second wall on the side of the second wall opposite to the second space and also extending in a direction parallel to the first direction.

6. A pressure controlling structure according to any one of claims 1-5, wherein the first wall, the two first side walls and the second wall define the second space and/or the second wall, the two second side walls and the third wall define the third space.

7. A pressure controlling structure according to any one of claims 1-5, wherein the first wall, the two first side walls, the at least one first dividing wall and the second wall define the second space and/or the second wall, the two second side walls, the at least one second dividing wall and the third wall define the third space.

8. A pressure controlling structure according to any one of claims 1-7, wherein at least one of the walls is provided with at least one protrusion protruding in the first space, the second space, the third space and/or the fourth space to further control waves of the pressure.

O

9. A pressure controlling structure according to any one of claims 1-8, wherein at least o 25 one of the walls is shaped to form at least one protrusion protruding in the first space, I the second space, the third space and/or the fourth space to further control waves of - the pressure. Xx a

10. A pressure controlling structure according to any one of claims 1-9, wherein the N pressure controlling device is formed of at least two sections split in a direction parallel N 30 to the first direction.

11. A pressure controlling structure according to claim 10, wherein each section comprises at least one first dividing wall.

12. A pressure controlling structure according to any one of claims 1-11, wherein the pressure controlling device is formed of at least two parts split in a direction transverse to the first direction, wherein each part comprises at least one first side wall.

13. A pressure controlling structure according to claim 12, wherein each part comprises two or more first side walls forming two or more second spaces adjacent to each other in the first direction in the part.

14. A pressure controlling structure according to any one of claims 10-13, wherein at least one of the sections and/or parts is formed as a separate structural part.

15. A pressure controlling structure according to any one of claims 1-13, wherein the pressure controlling structure is formed as one uniform structural part.

16. A pressure controlling structure according to any one of claims 1-15, wherein one or more third dividing walls are provided in an outermost space to divide the outermost space into two or more space sections.

17. A pressure controlling structure according to any one of claims 1-16, wherein in the area of at least a part of the pressure controlling structure closest to a first end of the pressure controlling structure provided with the inlet end the first space is connected to an outermost space via openings, and in the area of at least a part of the pressure controlling structure closest to an end opposite to the first end in the first direction the first space is not connected to the outermost space via openings. N <

18. A pressure controlling structure according to any one of claims 1-17, wherein the O pressure controlling structure comprises further spaces provided between the first oS o space and an outermost space. = 25

19. A pressure controlling structure according to any one of claims 1-18, wherein at least o < the first openings and the second openings are spread evenly along the 360 degrees [o circumference surrounding the first space and the second space in such a manner LO N that pressure provided in the first space can be dispersed evenly outwards from the

O . N first space.

20. A pressure controlling structure according to claim 19, wherein the first cross-sectional area of each first opening is smaller than the cross-sectional area of the first space, and the combined cross-sectional area of all the first openings along the 360 degrees circumference and provided, in each case, between two adjacent first side walls in the first direction is larger than the cross-sectional area of the first space.

21. A pressure controlling device comprising a pressure controlling structure according to any one of claims 1-20.

22. A method for controlling pressure, characterized in that the method comprises controlling pressure by a pressure controlling structure of any one of claims 1-20 or a pressure controlling device according to claim 21.

23. A method according to claim 22, wherein the method comprises dampening a sound caused by a pressure entering the pressure controlling structure in the first direction through an inlet opening provided at a first end of the pressure controlling structure by dispersing the pressure from a first space outwards in a radial direction. N N O N O <Q o I Za o + LO LO N N O N