WO2008140361A1

WO2008140361A1 - Mounting device, joint construction, ventilating arm, ventilating system

Info

Publication number: WO2008140361A1
Application number: PCT/SE2007/000460
Authority: WO
Inventors: Lars Karlander
Original assignee: Fumex AB
Current assignee: Fumex AB
Priority date: 2007-05-11
Filing date: 2007-05-11
Publication date: 2008-11-20
Anticipated expiration: 2009-11-11
Also published as: CN101678408B; EP2144718A4; CN101678408A; EP2144718A1

Abstract

This invention concerns a mounting device (1) for the mounting of an arrangement (2) or (3) on a ventilating arm (4) where the ventilating arm (4) comprises tube-shaped elements (5) joined to, and mobile relative to, each other by a rotating joint construction (6). The mounting device (1) is comprised within the joint construction (6) and offers a region (1.2)a at which the arrangement (2) or (3) is attached. The invention concerns also a joint construction (6), a ventilating arm (4) and a ventilating system A.

Description

Mounting device, joint construction, ventilating arm and ventilating system

This invention concerns a mounting device that makes possible the mounting of an arrangement on a ventilating arm according to the introduction to claim 1 , a joint construction of a ventilating arm according to the introduction to claim 10, a ventilating arm according to the introduction to claim 21 , and a ventilating system according to the introduction to claim 22.

Ventilating systems of various types are used to ventilate various spaces. Ventilating systems comprise air extraction arrangements and are used to transport away undesired airborne particles and substances, airborne contaminants, in various types of work environment. One example is the type of ventilating system that is used in laboratories, during assembly work, or during other types of work. A simple description of such a ventilating system is that it comprises an air-transport channel, an air-extraction unit at one end of the channel and an extraction mouthpiece at the second end of the channel, which is arranged at the source of the contamination or at a region that it is desired should be kept free of contaminants.

Such a ventilating system often comprises a ventilating arm that constitutes a part of the airtransport channel, that part that is located closest to the source of contamination or the region that is to be held free of contaminants. The ventilating arm in turn comprises parts that are connected to each other in such a manner that they can be bent, and their positions relative to each other can be adjusted, such that an extraction mouthpiece arranged at the outermost free end of the ventilating arm can be placed in the region of interest, where the contaminant is present or where it is not desired. Different designs of joint are available for this purpose. The rear part of the arm is connected to the air-transport channel, to tubes or to lines, or to both tubes and lines, through which the air is transported away.

In order for it to be possible to move the arm and lock it into a position, the arm comprises various forms of arrangement that can be activated and deactivated and that influence, guide and lock the motion of the ventilating arm. The arm comprises, for example, handles that can be gripped by a user who desires to move the ventilating arm, the extraction mouthpiece, to the desired location. The arm comprises also spring arrangements that make it possible to balance the arm's weight.

These arrangements, such as the said handles and spring arrangements, have previously been attached using various forms of attachment fittings that have been present on the external surface of the ventilating arms. Various types of tensioned straps, for example, attached around the tube elements of the arm have been used.

These attachments have led to long arrangements attached to various tube elements on each side of a joint functioning well in certain positions, while the arrangement in question has, in other positions, obstructed the ventilating arm, the mobile parts of the arm, the tube elements, or the joint. Alternatively, the joint, or one or both of the tube elements in the vicinity of the joint, have obstructed the arrangement. In those cases in which the arrangement comprises a spring or a spring-like construction, its function has ended when it has been "broken" by the joint or by the tube elements in the vicinity of the joint. The rotation in the joint, which is used to obtain motion of the tube elements relative to each other, has entailed too large a displacement of one of the attachment points of the arrangement in the ventilating arm. This has led to the ventilating arm becoming locked in certain positions, or reaching a position outside of a position at which the arrangement, the springs, no longer have functioned in the desired way.

Those parts of the arrangement that previously have been attached to the outer surfaces of the arms in order to make possible the mounting of these arrangements also themselves constitute obstructions during movement of the ventilating arm and its parts. They tend also to age and exhibit impaired function. Sometimes, they are not specially adapted for the area of application and this constitutes a further risk for safety and function. Also other parts and fittings that have been attached to the outer surfaces of the arms in order to make it possible to mount other fittings suffer from these problems.

One purpose of the present invention is to offer a mounting device that makes possible a simple and safe mounting of various arrangements onto a ventilating arm. Further purposes of the invention are to offer a joint construction that ensures a simple and safe mounting of various arrangements onto a ventilating arm, a ventilating arm to which arrangements can be simply and safely mounted, and a ventilating system that comprises a ventilating arm to which it is possible to attach arrangements simply and safely.

This purpose is achieved with a mounting device with the characteristics that are specified in the characterising part of claim 1 , a joint construction according to claim 10, a ventilating arm according to claim 21 and a ventilating system according to claim 22.

The invention will be described in more detail below with reference to Figures 1-7. Parts and fittings are labelled with reference numbers in the drawings. Parts and fittings that correspond to each other, or that are identical, in different drawings and in different embodiments have been given the same reference numbers.

Figure 1 shows a ventilating arrangement according to the invention.

Figure 2 shows a joint construction according to the invention.

Figure 3 shows a section through the joint construction shown in Figure 2.

Figure 4 shows a mounting device according to the invention.

Figure 5 shows also a mounting device according to the invention.

Figure 6 shows a joint construction according to the invention to which a spring arrangement has been attached. Figure 7 shows a joint construction according to the invention to which a handle has been attached.

A mounting device 1 according to the invention, see Figures 1 , 4 and 5, makes it possible to mount different arrangements 2 and 3 onto a ventilating arm 4, where the ventilating arm 4 comprises tube-shaped elements 5 connected to each other, and that can be rotated relative to each other, through joint constructions 6.

The ventilating arm 4 shown in Figure 1 comprises four tube-shaped elements 5, three joint constructions 6 and three mounting devices 1. The different arrangements that are attached to the ventilating arm 4 are a spring arrangement 2 and a handle 3. A mounting device 1 according to the invention can be used also to attach other types of arrangement to a ventilating arm.

Three mounting devices 1 according to the invention are shown in Figure 1. Each mounting device 1 is attached connected to a joint construction 6 as shown in Figures 2-4. The mounting device 1 comprises a first part 1.1 that is integrated with, and that is comprised within, the joint construction 6. The mounting device 1 comprises a second part 1.2 that protrudes from the joint construction 6 and that comprises a region 1.2a to which an arrangement 2 or 3 that it is desired to mount onto the ventilating arm 4 can be attached. The second part 1.2 of the mounting device 1 comprises, within the attachment region 1.2a, an attachment arrangement 7, or a part of an attachment arrangement that makes it possible to attach an arrangement 2 or 3, the spring arrangement 2 or a handle 3, that is to be mounted on the ventilating arm 4. The attachment arrangement 7 comprises, for example, a through hole 7.1 , see Figure 4, in which attachment means 8 can be arranged for interaction with, and the fixture of, the arrangement 2 or 3, the spring arrangement 2 or the handle 3, that is to be mounted on the ventilating arm 4. The attachment arrangement 7 may be also of any other suitable type that offers an attachment point with the desired properties. Each joint construction 6, which is a frictional joint, is arranged between and connected to two extended tube-shaped elements 5. Each tube-shaped element 5 comprises a hollow centre 5a and a first 5.1 open end and a second 5.2 open end. The tube-shaped elements 5 may be circular or elliptical when viewed in cross-section, they may have corners, or they may have another shape that functions well for the flow of air through it.

Each tube element comprises a first end 5.1 and a second end 5.2 directed towards and connected to a joint construction 6, an extraction mouthpiece 9, or an air extraction arrangement 10. The outer end 4.1 , which is free and which can be moved - the outermost first end 5.1 of the outermost tube element - of the ventilating arm comprises or is connected to an extraction mouthpiece 9 or similar, which facilitates the capture of air, the contaminant, that it is desired to remove. Each tube element 5 comprises a first end 5.1 that is directed towards the outermost, free, displaceable end 4.1 of the ventilating arm independent of its location at - along - the ventilating arm 4. Each tube element 5 comprises a second end 5.2 that is directed towards the rear end 4.2 of the ventilating arm, that end of the ventilating arm 4 that is connected to an air extraction arrangement 10, through which the air is filtered or transported away, or both. The rear end 4.2 of the ventilating arm, comprising the air extraction arrangement 10, is often mounted at some type of holding, supporting, construction, such as, for example a roof, a wall, a trolley, a framework, or similar.

Each joint construction 6 joins the first end 5.1 of a tube-shaped element to a second end 5.2 of a second tube-shaped element. The joint construction 6 joins these tube elements 5 with each other and makes it possible to adjust the positions of the tube elements 5 relative to each other.

Each joint construction 6 comprises an open inner space 6a in connection with the open inner spaces 5a of the tube elements 5, which are joined to each other through the joint construction 6 and through which air that is to be removed can pass.

The joint construction 6 comprises two joint halves 6.1 that are essentially identical and that are joined to each other and the relevant tube element 5. Each joint half 6.1 has the shape, in principle, of a cup, a cone that has been provided with a base. This shape entails inner side surfaces that direct and facilitate the flow of air through the joint construction 6, and the design offers also a shape that is easy to manufacture. It is easy, for example, to achieve the release of a joint half from a mould, if such is used for the manufacture, when the joint half has such an open shape. The joint construction 6 is manufactured from a plastic material or a composite material and it is shaped by methods that are previously known for these materials. Each joint half 6.1 comprises a bottom 11 , side parts 12, and a body 13 comprising a first opening 14 directed towards one of the tube elements 5 in order to achieve connection with the same. The body 13 is directed radially outwards from the joint half 6.1 , at its bottom 11. Each joint half 6.1 comprises further a second opening 15 corresponding to the opening of a cup if the joint half is viewed standing as a cup directed towards the second joint half. The joint halves 6.1 are mounted on each other with the relevant second openings 15 directed towards each other such that the inner compartment 6a of the joint comprises the inner compartments 6.1 a of the two joint halves and is contained by the two joint halves 6.1.

Each joint half 6.1 is principally cone-shaped in its design and construction, and it is circular when viewed from the direction of the second opening. This makes it possible to rotate the two joint halves 6.1 relative to each other around a central axis X, the central axis 6A of the joint construction, without this entailing any change of shape of the joint construction that introduces the risk of leakage. It is such a rotation of the two joint halves relative to each other that results in a change of position of the two tube elements 5 that are joined to each other by the joint construction.

The joint halves 6.1 are held together with the aid of a holder 16 that acts between the two joint halves 6.1. The holder 16 comprises an extended fixing element, a shaft element 16.1. The shaft element 16.1 has a design similar to that of a bolt that passes between the two joint halves 6.1 , passing through the complete joint construction 6 from the bottom 11 of one joint half through the open inner compartment 6a within the joint construction 6 to the bottom 11 of the second joint half. The shaft element 16.1 is placed under tension in this position.

The shaft element 16.1 comprises a construction 16.2 that is similar to a head at one end 16.1a and it has a fixture 16.3, which comprises, for example, an outer thread, at its second end 16.1b, and this makes it possible to attach a fixing device 16.4, for example a construction that is similar to a nut with an internal thread, to the shaft element 16.1 and to the fixture 16.3, and in this way to influence the active length L of the shaft element, which in turn makes it possible to place the two joint halves 6.1 in tension against each other under the influence of a force that can be varied. The construction 16.2 that is similar to a head may be arranged on the outer surface 6.1a of one of the joint halves or it may be an integral part of, or in, the joint half 6.1 , or its bottom 11. The fixing device 16.4 may be simply a nut, or a knob, or similar. The fixing device 16.4 may also make it possible to tighten the joint by screwing to a pre-determined torque through, for example, a certain length of thread, a stop peg on one of the interacting parts, or similar. The longitudinal axis 16A of the shaft element, the central axis, coincides with the central axis 6A of the joint construction. Rotation of the two joint halves 6.1 relative to each other takes places around the longitudinal axis 16A of the shaft element, the central axis 6A of the joint construction.

A joint arrangement 18 is arranged in each joint construction 6, between the joint halves 6.1 , between the edge surfaces 17 of the joint halves that face each other. The joint arrangement 18 is located between the two joint halves 6.1 and it ensures that the joint construction 6 does not leak. The joint arrangement 18 makes it possible also to rotate the two joint halves 6.1 , and thus also the two tube elements 5 that are connected to the relevant joint half 6.1 , relative to each other.

Each joint arrangement 18 of the ventilating arm 4 shown comprises a mounting device 1 according to the invention. The mounting device 1 comprises, as has previously been described, a first part 1.1 that is integrated with, that is comprised within, the joint construction 6, in the joint arrangement 18, and a second part 1.2 that protrudes from the joint construction 6. The mounting device 1 , the first part 1.1 , is a ring-shaped construction that has the form of a washer, that makes contact with and is fixed attached to one of the joint halves 6.1 , against the edge 17 of its surface.

The joint arrangement 18 comprises also a joint arrangement part 19, which is a ring-shaped construction similar to a washer, and which makes contact with, and is attached to, the other joint half 6.1. When the joint halves 6.1 are mounted against each other, the mounting device 1 and the joint arrangement part 19 make contact with each other and constitute the direct contact surfaces between the joint halves 6.1. The mounting device 1 and the joint arrangement part 19 form a lining for the original edge surfaces 17 of the joint halves 6.1.

The mounting device 1 , the first part 1.1 of the mounting device, and the joint arrangement part 19 both have a circular shape with an open inner section 1A and 19A, the sizes of which correspond essentially with each other, and which make possible the passage of air through the joint construction 6. The diameter of the open inner parts 1A and 19A correspond in principle with the diameter of the inner compartment 6a of the joint construction in the region that is limited by the areas 6.1a of the bodies that are directed towards each other.

The mounting device 1 , the first part 1.1 of the mounting device, and the joint arrangement part 19 make contact with the surface edge 17 of the relevant joint half and are connected to the joint half 6.1 in such a manner that when the joint halves 6.1 are mounted together, when the mounting device 1 and the joint arrangement part 19 are arranged against each other, a fixed connection arises between the relevant joint half 6.1 , the edge surface 17 of the joint half, and the mounting device 1 , the first part 1.1 of the mounting device, or the joint arrangement part 19. This fixed connection may, alternatively, already have been obtained before the component parts of the joint construction are assembled together.

The mounting device 1 comprises fixtures 20 on the surface 1a of the mounting device 1 , the first part 1.1 of the mounting device, that make contact with the joint construction 6, against the edge surface 17 of the joint half. The fixtures 20 lock the mounting device 1 in place relative to the joint construction 6 in a manner that allows it to be removed and to be locked again, such that the position of the mounting device 1 relative to the joint construction 6 can be adjusted, whereby the location of the attachment region 1.2a can be influenced and varied.

The fixtures 20 interact in a manner that retains in place and locks in position attachment means 21 comprised within the edge surfaces 17 of the joint half such that the mounting device 1 is retained in place in the desired position relative to the joint half 6.1 and the complete joint construction 6 and also the tube elements 5, principally when the joint halves 6.1 are arranged against each other, placed in tension in contact with each other. The fixtures 20 comprise protruding members 20a that are brought into interaction with, inserted into, the attachment means 21 that comprise indentations 21a that agree in shape with the protruding members 20a. The protruding members 20a and the indentations 21a may also be arranged in the opposite manner, such that the protruding members 20a constitute parts of the surface edge 17 of the joint half while the indentations 21a constitute parts of the surface 1 a of the mounting device.

This construction with fixtures 20 and attachment means 21 makes it possible to determine the position of the second part 1.2 of the mounting device, which protrudes from the joint construction 6, from the joint arrangement 18, relative to the joint construction 6. The mounting device 1 can be rotated around the central axis 6A of the joint construction following the edge surface 17 of the joint half and the existing fixtures 20 and attachment means 21 can be brought into contact with each other in a freely chosen manner within certain limits, these limits being determined by the distance between the fixtures 20 and the attachment means 21.

The determination of position and the positioning of the second half 1.2 of the mounting device entails also the determination of position of the mounting area 1.2a, the attachment arrangement 7, the hole 7.1 , relative to the joint construction 6 and the tube elements 5. The mounting device 1 can, before the joint construction 6 has been assembled, be rotated around the central axis 6A of the joint construction and it can be placed and its position locked relative to the joint construction 6, the relevant joint half 6.1 , at different positions such that the protruding second part 1.2 of the mounting device 1 is at a position at which it is desired to have an attachment point, that the mounting region 1.2a and thus the attachment arrangement 7 are placed at a location that can be selected and that can be changed. The number of fixtures 20 and attachment means 21 along the surfaces 2a and 17 that face in opposing directions can be selected such that the precision desired in determining the position of the protruding part 1.2 is obtained. The determination of position can take place with greater precision if the joint arrangement 18 comprises many fixtures 20 and attachment means 21 , than it can if they comprise few. The number of attachment means 21 can be lower than the number of fixtures 20, the number of protruding members 20a can be lower than the number of indentations 21a.

The joint arrangement 18 comprises also a sealing part 22, a sealing ring, that is arranged between the mounting device 1 and the joint arrangement part 19, in a space 23 between the mounting device 1 and the joint arrangement part 19 formed by an indentation 23a in the mounting device 1 and an indentation 23b in the joint arrangement part 19.

The sealing ring 22 is manufactured from a material that ensures the sealing function and the function as a connecting link between the mounting device 1 and the joint arrangement part 19, and it makes possible also rotation of the two joint halves 6.1 relative to each other, and thus also rotation of the two tube elements 5 that are connected to the relevant joint half 6.1.

The arrangements 2 and 3 that it is desired should be mounted on the ventilating arm 4 may be of different types, for example a spring arrangement 2 and a handle 3, as shown in the drawings.

Spring arrangements 2 of different types are used in order to balance the weight of the ventilating arm 4, which arrangements are arranged between the different mobile parts, most often between two tube elements 5 connected to each other through a joint construction 6. With a mounting device 1 according to the invention attached to the joint construction 6, one of the joint halves 6.1, it is possible to attach a first end 2a of the spring 2 to the mounting device 1 , to the protruding part 1.2, and in this way thus to the joint construction 6, to the joint half 6.1 of the tube elements that is connected to the tube element 5 to which this end 2a of the spring is to be attached. A second end 2b of the spring 2 can now be attached in a freely chosen manner and at a freely chosen location to the second tube element 5 that is located on the other side of the joint construction 6 and that is attached to the second joint half 6.1. The mounting device 1 offers a protruding part 1.2 that is indirectly connected to a tube element 5 to which the first end 2a of the spring is to be attached, and the second end 2b of the spring is attached at a freely chosen location on a second tube element 5. This means that the spring 2 acts between two different tube elements 5, while the attachment point of the first end 2a of the spring is not located on the other side of the joint construction 6, and for this reason there will not arise any placement of this attachment point, this end 2a of the spring, that entails any one of the joint halves 6.1 being locked by the spring 2 during its displacement, nor that the spring 2 will be subject to a bending moment at any position of the joint halves 6.1 or tube elements 5. A gas-filled spring will function admirably, since the motion will be accurately controlled in both directions.

Also the handle 3 is attached to a mounting device 1 according to the invention. The handle 3 comprises a first fixture 3a that is attached to the mounting device 1 , to the protruding part 1.2, with the aid of an attachment means 24. The handle 3 comprises further a second fixture 3b that attaches the handle 3 to the outer surface 6.1a of the joint construction, to the bottom 11 of the relevant joint half. The second fixture 3b is fixed attached with the aid of the holder 16. The second fixture 3b is held fixed against the joint construction 6 with the same force as that which holds together the joint halves 6.1. The second fixture 3b is held by compression between the fixture 16.4 and the joint construction 6, the joint half 6.1 , the outer surface 6.1a of the joint half, the bottom 11 of the joint half.

A mounting device 1 according to the invention, a joint construction 6 comprising such a mounting device 1 , a ventilating arm 4 comprising such a joint construction 6 and thus also such a mounting device 1 , constitute parts of a complete ventilating system A, as is shown in Figure 1 , and they facilitate the use of the complete system A in that it will be easier to mount arrangements 2 and 3 that facilitate the use and the handling of the system A. The ventilating system A comprises in addition to a mounting device 1 , a joint construction 6 comprising such a mounting device 1 , and a ventilating arm 4 comprising such a joint construction 6, a channel 25 for withdrawal with an air withdrawal unit 26 connected to the ventilating arm 4.

This description of different embodiments of the invention and of alternative designs of its fittings is not to be seen as a limitation of the invention: it is to be interpreted in its widest meaning such that it does not unnecessarily limit the protective scope according to the attached patent claims. Changes that lie within the expertise of one skilled in the arts lie within the protective scope of the innovative concept. The various designs of the fittings that are mentioned in the description above can be freely used and combined, provided that the desired function is obtained.

Claims

1. A mounting device (1 ) for the mounting of an arrangement (2, 3) on a ventilating arm (4) where the ventilating arm (4) comprises tube-shaped elements (5) joined to, and mobile relative to, each other by a rotating joint construction (6), c h a r a c t e r i s e d in that the mounting device (1) is comprised within the joint construction (6) and offers a region (1.2a) at which the arrangement (2, 3) is attached.

2. The mounting device (1) according to claim 1 , where the mounting device (1) comprises a first part (1.1 ) comprised within the joint construction (6).

3. The mounting device (1) according to claim 2, where the first part (1.1) is a ring-shaped construction that is similar to a washer, arranged between two parts (6.1 ) of the joint construction (6).

4. The mounting device (1 ) according to claim 2 or 3, where the first part (1.1) is circular with an open inner part (1A) that makes possible the passage of air through the joint construction (6).

5. The mounting device (1 ) according to any one of claims 1-4, where the mounting device (1) comprises a second part (1.2) that protrudes from the joint construction (6) and that comprises the region (1.2a) at which the arrangement (2, 3) is attached.

6. The mounting device (1 ) according to claim 5, where the region (1.2a) of attachment comprises an attachment arrangement 7 or a part of an attachment arrangement, that interacts with and retains the arrangement (2, 3).

7. The mounting device (1 ) according to any one of claims 1-6, comprising fixtures (20) on one surface (1a) of the mounting device (1 ) that make contact with the joint construction (6) and where the fixtures (20) lock the mounting device (1) in a fixed position relative to the joint construction (6) in a manner that allows it to be removed and locked again such that the position of the mounting device (1 ) can be adjusted relative to the joint construction (6) whereby the location of the region (1.2a) of attachment can be varied.

8. The mounting device (1) according to claim 7, where the fixtures (20) interact with attachment means (21 ) comprised within the joint construction (6).

9. The mounting device (1 ) according to claim 8, where the fixtures (20) or the attachment means (21) comprise protruding parts (20a) that interact with indentations (21a) comprised within the attachment means (21 ) or the fixtures (20).

10. A joint construction (6) comprising a mounting device (1) according to claim 1 , that makes it possible to mount an arrangement (2, 3) on a ventilating arm (4) comprising tube-shaped elements (5) joined by, and mobile relative to, each other through the joint construction (6) and that offers a region (1.2a) at which the arrangement (2, 3) is attached.

11. The joint construction (6) according to claim 10, where the joint construction (6) comprises two joint halves (6.1 ) that are joined to each other and together limit the inner compartment (6a) of the joint construction.

12. The joint construction (6) according to claim 10 or 11 , where each joint half (6.1) comprises a first opening (13) directed towards one of the tube elements (5) for connection to the same, and a second opening (15) directed towards the second joint half (6.1), towards the second opening (15) of the other joint half, for connection with the same.

13. The joint construction (6) according to claim 11 or 12, where the two joint halves (6.1) can be rotated relative to each other around the central axis (6A) of the joint construction while the form and the function of the joint construction (6) are retained.

14. The joint construction (6) according to any one of claims 11-13, comprising a holder 16 that acts between the joint halves (6.1 ), and holds them together.

15. The joint construction (6) according to any one of claims 11-14, comprising a joint arrangement (18) arranged between the joint halves (6.1), between their edge surfaces (17) that are directed towards each other.

16. The joint construction (6) according to claim 15, where the joint arrangement (18) comprises the mounting device (1).

17. The joint construction (6) according to claim 15 or 16, where the joint arrangement (18) comprises a joint arrangement part (19).

18. The joint construction (6) according to any one of claims 15-17, where the joint arrangement (18) comprises a sealing part (22) arranged between the mounting device (1) and the joint arrangement part (19).

19. The joint construction (6) according to any one of claims 10-18, comprising attachment means (21) that interact with fixtures (20) comprised within the mounting device (1) and lock the position of the mounting device (1 ) relative to the joint construction (6) in a manner that allows it to be released and relocked such that the position of the mounting device (1 ) can be adjusted relative to the joint construction (6) whereby the location of the attachment region (1.2a) can be varied.

20. The joint construction (6) according to claim 19, where the fixtures (20) or the attachment means (21) comprise protruding parts (20a) that interact with indentations (21a) comprised within the attachment means (21 ) or the fixtures (20).

21. A ventilating arm (4) comprising a joint construction (6) according to claim 10, which joint construction in turn comprises a mounting device (1) according to claim 1.

22. A ventilating system (A) comprising a ventilating arm (4) according to claim 21 , the ventilating arm comprising a joint construction (6) according to claim 10, which joint construction in turn comprises a mounting device (1 ) according to claim 1.

23. A mounting device (1 ) for the mounting of an arrangement (2, 3) on a ventilating arm (4) according to claim 1 , where the arrangement (2) is a spring arrangement (2).

24. A mounting device (1) for the mounting of an arrangement (2, 3) on a ventilating arm (4) according to claim 1 , where the arrangement (3) is a handle (3).