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Patent Searching and Data


Title:
SPRAY HEAD
Document Type and Number:
WIPO Patent Application WO/2007/051897
Kind Code:
A1
Abstract:
Spray head, especially for forming and spraying a mist, said spray head comprising a frame part (1), an inlet (2) and a main channel (5) formed in the frame part and leading from the inlet to at least one opening (4) formed in the wall of the frame part, characterized in that the spray head comprises at least one second part (7) arranged in it, in which second part is formed at least one opening (8) which, together with the opening (4) formed in the wall of the frame part, constitutes a spraying nozzle.

Inventors:
SUNDHOLM GOERAN (FI)
METZGER HARRY (FI)
Application Number:
PCT/FI2006/000346
Publication Date:
May 10, 2007
Filing Date:
October 31, 2006
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
MARIOFF CORP OY (FI)
SUNDHOLM GOERAN (FI)
METZGER HARRY (FI)
International Classes:
A62C31/02; A62C31/05; A62C37/08; A62C37/11; B05B1/02; B05B1/30; B05B7/04; B05B1/14; B05B1/16; A62C
Domestic Patent References:
WO2005102536A12005-11-03
Foreign References:
EP0927562A21999-07-07
JPS60241461A1985-11-30
US6318474B12001-11-20
US20050011652A12005-01-20
US5944113A1999-08-31
Other References:
See also references of EP 1942994A4
Attorney, Agent or Firm:
HEINÄNEN OY (Helsinki, FI)
Download PDF:
Claims:

Claims

1. Spray head, especially for forming and spraying a mist, said spray head comprising a frame part (1), an inlet (2) and a main channel (5) formed in the frame part and leading from the inlet to at least one opening (4) formed in the wall of the frame part, characterized in that the spray head comprises at least one second part (7) arranged in it, in which second part is formed at least one opening (8) which, together with the opening (4) formed in the wall of the frame part, consti- tutes a spraying nozzle.

2. Spray head according to claim 1, characterized in that the second part (7) is arranged inside the frame part.

3. Spray head according to claim 1, characterized in that the second part (7) is arranged outside the frame part (1).

4. Spray head according to claim 2, characterized in that the second part (7) is arranged in the main channel (5) of the frame part.

5. Spray head according to claim 2 or 3, characterized in that the second part (7) is a sleeve-like part, the opening (8) being formed through the wall, especially a side wall, of said sleeve-like part.

6. Spray head according to any of claims 1 - 5, characterized in that the opening (8) in the second part (7) is arranged at substantially the same angle with the opening (4) in the frame part (1).

7. Spray head according to any of claims 1 - 6, characterized in that the opening (8) in the second part is arranged at a different angle

(α) relative to the opening (4) in the frame part.

8. Spray head according to any of claims 1 - 7, characterized in that it has one opening (8) of the second part in the coverage area of the opening (4) in the frame part.

9. Spray head according to any of claims 1 - 8, characterized in that it has at least two openings (8', 8") of the second part in the coverage area of the opening (4) in the frame part.

10. Spray head according to any of claims 1 -9, characterized in that the openings (8, 8', 8") arranged in the second part (7), i.e. in the sleeve part, are arranged at an angle (β) relative to a central channel (9).

11. Spray head according to any of claims 1 - 10, characterized in that the openings (8', 8") provided in the second part (7) are arranged at a different angle relative to each other.

12. Spray head according to any of claims 1 - 11, characterized in that the second part (7) is arranged to be movable.

13. Spray head according to any of claims 1 - 12, characterized in that the second part (7) is arranged to be movable between at least two positions, a first position, in which at least one first opening (8') is in the coverage area of the opening (4) in the frame, and a second position, in which at least one second opening (8") is in the coverage area of the opening (4) in the frame.

14. Spray head according to any of claims 1 - 13, characterized in that the second part (7) is arranged to be movable by the sprayed medium.

15. Spray head according to any of claims 1 - 14, characterized in that the sleeve part (7) is arranged to be movable by a pressure dif- ference.

16. Spray head according to any of claims 1 - 15, characterized in that it has a constriction region (19) arranged in the second part (7).

17. Spray head according to any of claims 1 - 16, characterized in that it comprises a valve element (6) slidably arranged in the main channel (5) of the spray head or in the channel (9) in the second part,

said valve element (6) being movable between at least two positions, a first position, in which it blocks the passage between the inlet (2) and at least one nozzle (4, 8, 8', 8"), and a second position, in which the passage from the inlet to the at least one nozzle is open.

18. Spray head according to any of claims 1 - 17, ch a ra cte ri zed in that, in the direction of medium flow, the first opening (8, 8', 8") of the nozzle is smaller than the second opening (4).

19. Spray head according to any of claims 1 - 18, ch a ra cte ri zed in that the diameter (d) of the first opening (8, 8', 8") equals 0.1 - 0.9 times the diameter (D) of the second opening.

20. Spray head according to any of claims 1 - 19, ch a ra cte ri zed in that a medium passage (23) is provided between at least some of openings (4).

21. Spray head according to any of claims 1 - 20, cha racterized in that the second part (7) and/or the frame part (1) are/is provided with a groove (23) or the like.

22. Spray head according to any of claims 1 - 21, ch a ra cte rized in that the second part (7) has openings (8) arranged in the coverage area of only some of the openings (4) in the spray head frame.

23. Spray head according to any of claims 1 - 22, ch a ra cte ri zed in that some of the openings (4) in the frame function as medium spraying openings and those of the openings opposite which there is no opening (8) in the sleeve can function as air supply openings (4').

24. Spray head according to any of claims 1 - 23, ch a racterized in that every second hole (4) functions as a nozzle whereas air flows in through the other every second hole (4') when the nozzle (8, 4) functions like an ejector.

Description:

SPRAY HEAD

Background of the Invention

The invention relates to a spray head as defined in the preamble of claim 1.

Prior-art spray heads known in fire-fighting technology include spray heads, especially sprinkler heads, provided with a valve element which, when in a non-activated state, blocks the liquid passage and when the sprinkler is activated upon being triggered, e.g. by a thermally activated ampoule being broken, assumes a position in which the extinguishing medium can flow into one or more nozzles. A sprinkler head of this type is disclosed in US patent 6,318,474. In the solution presented in this specification, the nozzles are formed by making in a frame a first boring and a second boring, each nozzle being formed by these borings together. The first boring has a first diameter, and the second boring has a second diameter. The spray head produces medium mist very efficiently. However, the disclosed solution is demanding in respect of manufacturing technology and imposes restrictions regarding the dimensions of the first boring and the second boring on the one hand and, on the other hand, regarding their mutual orientations.

The object of the present invention is to produce a completely new type of solution for use in conjunction with spray heads, in particular sprinkler heads, that will make it possible to achieve a structure improved in respect of manufacturing technology. Another object of the invention is to create a spray head whose properties can be varied according to need, e.g. in a manner optimized for each application.

Brief description of the invention

The invention is based on a concept whereby the frame of the spray head is provided with a second part, such as a sleeve part, the wall of which is provided with at least one opening, so that the opening in the second part and the opening arranged in the frame part together form at least one nozzle of the spray head. According to the concept of the

invention, the second part may be provided with at least one opening formed in a desired manner, whose dimensions, shape and/or orientation can be formed and, if necessary, optimized according to the application. According to yet another concept of the invention, the second part may be formed to be movable.

In more accurate terms, the spray head of the invention is characterized in that the spray head is provided with at least one second part with at least one opening formed in it, which opening together with the opening formed in the wall of the frame part forms a spraying nozzle.

The spray head of the invention is additionally characterized by what is stated in claims 2 - 24.

The solution of the invention has numerous significant advantages. The spraying properties of the spray head can be varied according to the application by using different combinations of frame and second part, such as sleeve part. The spray head of the invention is very reliable in operation. It has a very good structure in respect of manufacturing technology. The invention allows e.g. solutions in which the dimensions and/or orientations of the nozzle opening formed in the frame and of that formed in the second part differ considerably from each other. This makes it possible to achieve a considerably larger range of application and/or range of variation of nozzle properties than in the case of prior- art solutions, especially when compared to a nozzle head in which the openings, such as borings, formed by the nozzle are made in the same body, such as the frame of the nozzle head. By using an arrangement where the orientation of the opening formed in the second object and the orientation of the opening formed in the frame are at an angle rela- tive to each other, the shape of the spray can be adjusted by varying the angle. This allows a very large range of variation of the spraying properties of the spray head. The openings in the frame and in the second part may be oriented in mutually different directions not only in relation to the vertical axis of the spray head but also tangentially relative to each other.

The solution of the invention permits several openings to be formed in the second part, which are in connection with, i.e. in the coverage area of the nozzle opening formed in frame of the nozzle head. By forming two or more holes in the second part in connection with the opening formed in the frame, it is possible to adjust the shape of the spray delivered by the nozzle. Thus, it is also possible to achieve a spray with a better penetration as necessary, which has a great importance in certain fire-fighting applications, especially those based on liquid mist.

By forming a connection between the different nozzles in the nozzle head, e.g. by forming a medium channel between the frame and the second part, it is possible to further extend the properties of the spray head. The medium channel can be effectively created e.g. by forming a groove in the second part or in the frame or in both. In this case, by providing the second part, such as a sleeve part, with openings in conjunction with only some of the openings in the frame of the spray head, the spraying properties of the spray head can be further extended. Some of the openings function as nozzles, and those of the openings opposite which there is no opening in the second part, such as a sleeve, can now function as air supply openings. The second part, such as a sleeve, may have a groove formed in the area opposite to the holes bored in the frame, so that at least some of the holes communicate with each other. Thus, e.g. every second hole functions as a nozzle whereas air flows in through the other every second hole when the nozzle func- tions like an ejector. The additional air supply holes make it possible to influence the shape and penetration of the spray discharged. Without supplementary air, the spray produced is e.g. broader and/or softer, whereas by using supplementary air e.g. a narrower and/or sharper spray is produced.

The second part, such as a sleeve, and the frame can be arranged to be movable relative to each other. Preferably the second part is formed to be movable in the frame between at least two positions. This makes it possible to arrange for structural features giving a particular spraying property to be in alignment with each other between the frame and the second part in a first position, and for structural features giving a different spraying property to be in alignment with each other in a second

position. In this case, e.g. when the sprayed medium has a higher pressure, the spray head can be arranged to have different properties than if the pressure of the sprayed medium were lower. By using the medium pressure and a counter-element for it, such as a pre-tensioning element, especially a spring element, it is possible to achieve a solution for varying the properties of a spray head that is very reliable in operation and advantageous in respect of manufacturing technology. By using a sleeve element as the second part, a very advantageous solution is achieved. By forming a throttle element in the sleeve element and using a counter-element, a very usable and reliable solution for moving the second element by the medium pressure is obtained. By providing the upper end of the sleeve with a throttle hole, a pressure difference is produced which, at higher outputs of sprayed medium, presses the sleeve down, giving a different spray. With a lower output of medium, the pressure difference decreases and the spring used as a counter- element causes the sleeve to rise upwards and a new hole gives a new type of spray.

Brief description of the figures

In the following, the invention will be described in detail by referring to an example and the attached drawings, wherein

Fig. 1 represents a spray head according to the invention, especially a sprinkler head, sectioned in a readiness position along line A-A in Fig. la,

Fig. Ia represents a sprinkler head according to the invention as seen from the end opposite the medium supply channel,

Fig. 2 represents the sprinkler head of Fig. 1, sectioned in an activated position,

Fig. 3 represents a magnified detail of a spray head nozzle in sectioned view,

Fig. 4 represents magnified detail of a spray head nozzle,

Fig. 5 represents a magnified detail of a second embodiment of the spray head nozzle,

Fig. 6 represents a magnified detail of the spray head nozzle,

Fig. 7 represents a magnified detail of an embodiment of the spray head nozzle in sectioned view,

Fig. 8 represents a magnified detail of an embodiment of the spray head nozzle in sectioned view,

Fig. 9 represents a second embodiment of the spray head of the inven- tion in a first position,

Fig. 10 represents a second spray head according to the invention in a second position,

Fig. 11 represents yet another embodiment of the spray head,

Fig. 12 represents the spray head sectioned along line B-B in Fig. 11, and

Fig. 13 represents a detail of the spray head, sectioned along line XIII- XIII in Fig. 12.

Detailed description of the invention

Figs. 1, Ia and 2 represent a spray head according to the invention. The spray head illustrated in the figures is a sprinkler head specifically designed for fire-fighting. The spray head is intended particularly for spraying a medium mist. The spray head has a frame part 1 and an inlet 2 for supplying a medium to be sprayed to the spray head. The frame part 1 is provided with a boring 5. Arranged in the boring 5 is a second part 7, preferably a sleeve-like part having a first end 10 and a

second end 11. The second part contains at least one channel 9 forming a passage through it from the first end 10 to the second end 11. At least one first opening 8 is formed through the wall of the second part. The frame part 1 has at least one opening 4. The opening 8 in the sec- ond part 7 and the opening 4 in the frame part 1 are arranged to function together so that, when a medium is flowing through them, the nozzle head produces a medium spray, especially a medium mist spray. The opening 8 in the second part is thus in the coverage area of the frame part. In the embodiments presented in Figs. 1 and 2, the spray head comprises a valve element 6 which, in the position shown in Fig. 1, is arranged to block the medium flow passage from the inlet 2 to the nozzle formed by the openings 8, 4. By providing the second part with opening 8 and the frame part with opening 4, it will be possible to advantageously vary different frame part 1 - second part 7 combinations with openings 8, 4 having different properties. In the figures, the second part 7 is arranged inside the frame part 1, in a channel 5, but alternatively it is conceivable that the second part could be arranged outside the frame part, at least in the area where at least some of the nozzle holes of the frame part are arranged.

Arranged in the boring in the frame is a sealing element 12 or the like. The sealing element 12 is preferably placed in the boring, pressed between the second part 7 and the part 3 on the inlet side, so that it, together with the valve element 6 movably arranged in the boring in the frame, closes the passage into the channel 9 in the sleeve. In its first position, the valve element 6, i.e. plunger blocks the medium flow passage to the nozzles 8, 4. In the case of Fig. 1, the valve element is locked in the first position by locking means 14, 15. In the embodiment in the figure, the means for locking and/or releasing the valve element comprise a heat-sensitive element 14. The heat-sensitive element 14 may be e.g. an ampoule known in itself in fire-fighting technology, which breaks at a certain temperature. Similarly, the heat-sensitive element 14 may melt at a certain temperature. Naturally, the means for releasing the valve element may also consist of other types of devices, and they could conceivably function e.g. on the basis of a signal coming from the control system of a fire-fighting system. Formed in the valve element 6 is a boring 16, into which the upper end 18 of the ampoule

14 as seen in the figure is arranged to fit. The total length of the ampoule 14 and valve element 6 is fitted to be such that, when the ampoule is in position, the valve element is in a blocking position.

When the spray head is activated as the heat-sensitive element is broken, the medium pressure acting on the valve element 6 end facing towards the inlet 2 causes the valve element 6 to move to a second position (Fig. 2), in which the passage to at least one nozzle 8, 4 is open.

In the embodiment in the figure, the valve element 6 has at least one opening 17 formed in it, extending from space 9 into boring 16. The boring can now act as a spraying nozzle when the spray head is in the activated state, in a situation as illustrated in Fig. 2.

Figs. 3 and 4 present a magnified detail of a spray head according to the invention. According to these figures, the opening 4 formed in the frame part 1 has a larger diameter D than the opening formed in the second part 7, which has diameter d. In this embodiment, the openings are disposed coaxially relative to each other.

Figs. 5 and 6 present a second embodiment, in which the opening in the second part is arranged to be at an angle α relative to the opening 4 formed in the frame. In this embodiment of the invention, the size and shape and orientation of the opening can be easily varied by using a dif- ferent second part 7. In respect of manufacturing technology as well, it is possible to achieve more versatile spray head solutions when a separate second part is used, as compared e.g. to a solution where the nozzle openings are arranged in the same body. By using an arrangement where the orientation of the opening formed in the second body and the orientation of the opening formed in the frame are at an angle relative to each other, the shape of the spray can be controlled by varying the angle. This allows a very large range of variation of the spraying properties of the spray head. The openings in the frame and in the second part may be oriented in mutually different directions not only in relation to the vertical axis of the spray head but also tangentially relative to each other.

Figs. 7 and 8 present yet another preferred embodiment, in which the second part is provided with several openings 8', 8", which are simultaneously in the coverage area of the opening 4 formed in the frame. The openings formed in the second part may differ from each other in re- gard of their dimensions and orientations. By forming two or more holes in the second part 7 in conjunction with the opening 4 formed in the frame 1, it is possible to influence the shape of the spray delivered by the nozzle. Thus, it is also possible to achieve a spray with a better penetration as necessary, which has a great importance in certain fire- fighting applications, especially in those based on liquid mist.

Figs. 11, 12 and 13 present a third embodiment of the solution of the invention, wherein some of the openings 4 formed in the frame are arranged to function as air passages. In this case, a connection is pro- vided between different openings 4, e.g. by forming a medium channel 23 between the frame 1 and the second part 7, allowing the properties of the spray head to be further extended. The medium channel 23 can be effectively created e.g. by forming a groove 23 in the second part 7 (Fig. 13) or in the frame or in both. In this case, by providing the sec- ond part with openings in conjunction with only some of the openings in the frame of the spray head, the spraying properties of the spray head can be further extended. Some of the openings function as nozzles, and those of the openings opposite which there is no opening 8 in the sleeve can now function as air supply openings. The sleeve 7 may have a groove formed in the area opposite to the holes bored in the frame, so that at least some of the holes communicate with each other. Thus, e.g. every second hole functions as a nozzle whereas air flows in through the other every second hole when the nozzle functions like an ejector. The additional air supply holes make it possible to influence the shape and penetration of the spray discharged. If no supplementary air is used, e.g. a broader and/or softer spray can be produced, whereas by using supplementary air e.g. a narrower and/or sharper spray can be produced.

Figs. 9 and 10 present yet another embodiment of the invention. The second part 7, such as a sleeve part, and the frame 1 can be arranged to be movable relative to each other. Preferably the sleeve part 7 is

formed to be movable in the frame, e.g. in the channel 5, between at least two positions. In Fig. 9, the sleeve part is in a first position, and in Fig. 10 the sleeve part is in a second position. The second part is slidably arranged in the channel 5. In the embodiment illustrated in the figures, the second part 7 comprises a groove with a sealing element 22, such as an O-ring or the like, arranged in it. It is now possible to arrange for structural features, such as the size, shape and/or orientation of the openings 8', 8" (and 4) giving a particular spraying property to be in alignment with each other between the frame 1 and the second part 7 in the first position, and for structural features giving a different spraying property to be in alignment with each other in the second position. In this case, e.g. when the sprayed medium has a higher pressure, the spray head can be arranged to have different properties than if the pressure of the sprayed medium were lower. Such cases can be utilized e.g. in fire-fighting applications. By using the medium pressure and a counter-element for it, such as a pre-tensioning element, especially a spring element 20, 21, to assist the motion of the second part, it is possible to achieve a solution for varying the properties of the spray head that is very reliable in operation and advantageous in respect of manu- facturing technology. By using a sleeve element as the second part 7, a very advantageous solution is achieved. By forming a throttle element 19 in the sleeve element and using a counter-element 20, 21, a very usable and reliable solution for moving the second part 7 by the medium pressure is obtained. By providing the upper end 10 of the sleeve with a throttle hole 19, a pressure difference is produced which, at higher outputs of sprayed medium, presses the sleeve 7 down (Fig. 10), giving a different spray. With a lower output of medium, the pressure difference decreases and the spring 20,21 used as a counter-element causes the sleeve to rise upwards and a new hole 8' gives a new type of spray (Fig. 9).

According to an embodiment, the counter-element is a pre-tensioning element, especially a spring element 20, 21. The pre-tensioning element is preferably a cup spring element 20, 21.

Thus, the invention relates to a spray head for spraying a mist, said spray head comprising a frame part 1, an inlet 2 and a main channel 5

formed in the frame part and leading from the inlet to at least one opening 4 formed in the wall of the frame part. Arranged in the spray head is at least one second part 7 with at least one opening 8 formed in it, which, together with the opening 4 made in the wall of the frame, forms a spraying nozzle.

According to a preferred embodiment, the second part 7 is arranged inside the frame part 1.

According to a preferred embodiment of the invention, the second part 7 is arranged in the main channel 5 of the frame part. In the embodiments illustrated in the figures, the second part 7 is a sleeve-like part, and the opening 8 is formed through the wall, especially a side wall, of the sleeve.

In an embodiment, the opening 8, 8', 8" in the second part is arranged to be at substantially the same angle with the opening 4 in the frame part (Fig. 3).

According to another embodiment, the opening 8 in the second part is arranged to be at a different angle α relative to the opening 4 in the frame part. Fig. 5 additionally shows certain other angles. Angle β indicates the direction of the opening 8 relative to the main direction of the spray head channel 9. Angle βr represents the direction of opening 4 relative to the main direction of the channel 9. In spray heads implemented according to the invention, angle β may vary within a considerably larger range than usual. For example, US 6,318,474 gives some values between 0 - 120°. In the solution of the invention, angle α may vary considerably from prior-art solutions, because neither manufactur- ing technology nor the dimensions of the opening 4 impose any restrictions regarding the making of the opening 8, 8', 8" to be formed in the second body. Thus, the size and shape and orientation of the opening 8, 8', 8" can be optimized in accordance with the desired spraying properties.

According to a third embodiment of the invention (Fig. 7), it is even possible to provide more than one opening of the second part in the

coverage area of the opening in the frame part. In Fig. 7 ', the spray head has at least two openings of the second part in the coverage area of the opening in the frame part.

The openings provided in the second part 7, i.e. in the sleeve part in the embodiment illustrated in the figures, are arranged at angle β relative to the central channel of the sleeve. The openings 8', 8" provided in the second part 7 are arranged at a different angle relative to each other.

The second part 7, which according to an embodiment is a sleeve part, is arranged to be movable. The sleeve part 7 is arranged to be movable between at least two positions, a first position, in which at least one first opening 8' is in the coverage area of the opening 4 in the frame, and a second position, in which at least one second opening 8" is in the coverage area of the opening 4 in the frame.

The sleeve part 7 is arranged to be movable by the sprayed medium. The sleeve part 7 is arranged to be movable by a pressure difference.

The sleeve part 7 has a constriction region 19 arranged in it. Arranged in the spray head is a counter-element, such as a pre-tensioning element, especially a spring element, preferably a cup spring element 20, 21. Thus, the sleeve part remains in the first position and will not move to the second position until the medium pressure in the spray head is sufficiently high. After the pressure has fallen, the spring element returns the sleeve element back to the first position again.

Slidably arranged in the main channel 5 of the spray head or in the channel 9 in the second part is a valve element 6, said valve element 6 being movable between at least two positions, a first position, in which it blocks the passage between the inlet 2 and at least one nozzle 4, 8, 8', 8", and a second position, in which the passage from the inlet to the at least one nozzle is open.

In the direction of medium flow, the first opening 8, 8', 8" of the nozzle in the embodiments illustrated in the figures is smaller than the second opening 4.

The diameter d of the first opening 8, 8', 8" is typically 0.1 - 0.9 times the diameter D of the second opening 4. Typical parameters and measurements related to the dimensions of the spray head openings are pre- sented in US patent 6,318,474. The dimensions of the nozzles described in this specification have been found to be advantageous in the spraying of liquid-containing mist. Naturally, other opening sizes may be usable depending on the application.

In yet another embodiment, a medium passage is provided between at least some of openings 4. The second part 7 and/or the frame part 1 is provided with a groove 23 or the like.

The second part 7 may have openings 8 arranged in the coverage area of only some of the openings 4 in the spray head frame. Some of the holes 4 function as nozzles, and those of the holes opposite which there is no opening 8 in the sleeve can thus function as air supply openings.

In the embodiment in Fig. 12, every second hole 4 functions as a nozzle whereas air flows in through the other every second hole 4' when the nozzle 8, 4 works like an ejector. As the medium spray is discharged through the opening 8 in the second part and the opening 4 in the frame, it creates a suction, so that air flows in through opening 4' and is passed via the medium passage, such as a groove 23, to opening 4 and is mixed into the spray discharged from the spray head. In Fig. 12, the directions of flow are visualized by arrows.

The general operation of the spray head of the invention is not explained in detail in the description, but it is assumed to be obvious to a person skilled in the art. In this connection, reference is made to US patent 6,318,474.

It is obvious to a person skilled in the art that the invention is not limited to the embodiments described above, but that it can be varied within the scope of the claims presented below. Features that may have been presented together with other features in the above description may also, if necessary, be independent features. Alternatively, it is conceivable that the second part is arranged outside the frame part 1. In

this case, the dimensions and orientations of the openings 4, 8, 8', 8" in parts 1 and 7 respectively are mutually reversed relative to those presented in the figures. The second part may also be other than a sleeve- like part. It is likewise conceivable that the second part comprises sev- eral components or is formed from several components.