DE29920094U1 - Fitting of an at least fixable, but preferably also movable wing of a window or a door - Google Patents

Description

S199127G Applicant: SIEGENIA-FRANK KG, Eisenhüttenstraße 22,

57074 Siegen, Germany
REF: 1 004 808

Fitting of a window or door wing that can at least be lifted, but preferably also moved

The innovation relates to a fitting of an at least liftable, but preferably also movable, sash of a window or door, with a guide rail, wherein an actuating rod is located on the sash, which has a drive rod that can be moved downwards by means of an actuating member to lower the sash.

Lowering the sash therefore causes it to close due to its own weight.

As a rule, liftable sashes are also adjusted after being lifted, particularly moved to the side. In the case of a door, this creates a passage opening. In the closed position, the sash must be as sealed as possible from the fixed frame. For this purpose, it is equipped with sealing strips or similar, which rest against corresponding counter-sealing surfaces on the fixed frame when the sash is lowered. Accordingly, such sealing strips are located not only at the top and bottom ends, but also on the two longitudinal beams. If the sash is only lifted, the top and bottom seals are released, but not the side seal. If this sash is to be lowered again, the friction of the seals counteracts the lowering movement. With a relatively light and high sash, this friction can reach a value that can no longer be ignored, which counteracts the lowering movement resulting from the weight of the sash in such a way that the sash is not lowered, or at least not completely. At the end of the lowering movement, the transverse seals must also be pressed

-2-

If such a wing can also be tilted, for example, there may also be problems with the locking mechanisms required for this.

In order to remedy this situation, a device has become known from DE 8809998 U1 which causes the sash to be lowered forcibly. It essentially consists of a sliding element and a double-armed lever arranged between this and the vertical drive rod which is usually present on the closing side anyway. At least during the final lowering movement, a downward-facing surface of the drive rod presses against the lever arm of the double-armed lever, the other lever arm of which rests against a downward-facing surface, in particular the lower end surface of the sliding element. During the final lowering movement, at least the upper end of the sliding element rests against a part which is fixed to the frame, which could be an upper guide rail for example. The further downward movement of the drive rod via the double-armed lever mounted on the sash causes the sash to be forced down.

In order to achieve increased protection against burglary while simultaneously forcing the sash to be lowered, a locking mechanism is not visible in the embodiment - lowering device in engagement with the locking element. There is no locking in the direction of displacement according to this design variant, even if it does have resistance to displacement, which is only declared as frictional resistance. As a result, additional locking mechanisms are required for this fitting variant to also secure the sash against displacement. In a design variant that consists of three sash components, with two fixed sashes arranged on the respective outer sides of the frame and the sliding or tilting sash mounted in the middle between the two fixed sashes and where the sliding sash does not have a vertical frame wood with locking elements, the known lowering device can only be used with a large amount of component expenditure - not shown.

Other lowering devices are known from EP 0152791 B1. This device also serves to lower the sliding sash using a vertical actuating rod, which causes the sliding sash to be moved and raised and to close it under its own weight. This is done by means of a slider which is driven by a reversing pinion and thus works in the opposite direction to the

The drive rod is movable, with the entire adjustment device being housed in a U-shaped faceplate profile. In the locked position, the sash rests against the vertical plane of the frame and a locking member passes through a slot-like opening in the faceplate profile. The drive rod is moved downwards, which engages behind the locking member, with the slider moving upwards in the opposite direction. The end has a support stop that rests against the locking member and thus forcibly lowers the sash.

This known design is also not designed to cover all design variants. Furthermore, both known designs have a one-piece design, so that the one-piece design is used even for heavy wings that have no problem lowering themselves due to their own weight. As a result, the fitting becomes unnecessarily expensive.

The innovation is therefore based on the task of achieving increased burglary protection with the lowest possible component expenditure, whereby all possible design variants of a sash that can at least be lifted and preferably moved should be covered.

This object is achieved according to the innovation in that the fitting has a locking device which can be coupled to the actuating rod and has a drive rod section which can be moved against the drive rod of the actuating rod, wherein a latch is provided on the drive rod section which, in the locking position, is in engagement with a latch engagement and rests against a contact edge of the latch engagement and that the latch engagement is directly assigned to one of the guide rails.

The new fitting has the significant advantage that the existing fitting can be retrofitted with a locking device at any time, and also has a locking element and a locking engagement, thus increasing protection against burglary, while at the same time forcing the sash to be lowered via the contact edge of the locking engagement. It is also possible to cover all design variants of a window or door sash that can at least be lifted, but preferably also moved, using a locking device and locking engagements that are specific to the design.

Another preferred development provides that the locking device has a faceplate profile which is essentially U-shaped and accommodates all components of the locking device.
5

The advantage here is that the locking device is based on the external conditions of the operating rod and, due to the integral design, facilitates installation on the inner wing.

In order to further improve the locking device, a clearance for receiving a guide part is provided on the end of the faceplate profile facing the guide rail and is firmly connected to the guide part by means of a fastening means.

This design also proves to be a significant simplification of assembly, since the clearance allows for immediate alignment of the locking device with the guide part and the fastening means can be attached quickly. In addition, the locking device is simultaneously firmly aligned on the sash.

Another feature is that the end of the faceplate profile facing the operating rod has a cover.

In order to cover the interface between the locking device and the operating rod as far as possible, it is recommended to punch out the side parts of the U-shaped faceplate profile in order to bend the cover plate so far that the operating rod is partially covered. This creates a simple cover without the need for a second component.

A practical, simple and cost-effective production of the locking device is ensured if the faceplate profile is divided into two cross sections, one cross section serving to guide the drive rod section and the other cross section accommodating a number of parts of the locking device, including a sliding element which is guided and held in the cross section.

A further feature of the innovation is that the sliding element is kept in constant drive connection with the drive rod section by at least one reversing pinion.

The advantage here is that the reversing pinion generates the actual reversing movement in order to ultimately lower the sash and enable it to engage the upper locking latches.

According to the invention, it is structurally simple and particularly economical to manufacture if a component takes on several functions that have a particularly advantageous effect on the locking device. The sliding element is one of these components, which has a coupling shoe with two fastening means for receiving a connecting element at one end and the other end is L-shaped, with one side having an elongated hole for guiding the reversing pinion and the other side containing a toothing. The toothing transfers the rotary movement of the reversing pinion into a reverse sliding movement on the drive rod section of the locking device.

A practical and simple assembly of the locking device is ensured if the locking device has two bearing plates onto which a certain number of individual parts of the locking device can be pre-assembled in order to then install them in the locking device. At the same time, this pre-assembly measure is recommended in order to give the reversing pinion the necessary support that is required in the event of unforeseen forces.

Another advantageous way to simplify assembly is to use at least two round bushings with a cutout to attach the bearing plates to the pre-assembled individual parts. The bearing plates with the pre-assembled parts are then inserted and adjusted using at least two dowel pins that are pushed through the faceplate profile and the round bushings and are then fixed to the faceplate profile, for example using rivets.

Another advantage is that no additional space is required on the bearing plates to fix them using dowel pins, and at the same time no additional material is required.

A further feature is that a coupling shoe is mounted on the ends of the actuating rod facing the locking device, said coupling shoe having two fastening means for receiving and fastening the connecting element.

The advantage here is that the fastening means provide a further adjustment option for positioning the locking device.

A practical, simple and cost-effective production of the latch is ensured if the latch is manufactured as a stamped and bent part. At the same time, this gives the component a high level of strength, which is considered essential in the event of a possible break-in attempt. The latch also has a lead-in slope that makes it easier to lock into the latch engagement, but which also acts as a pull on the sash.

Another preferred development is characterized in that the locking engagements are held displaceably on the respective guide rails.

A particularly advantageous feature is that the closing position of the movable sash can be precisely adjusted and readjusted at any time. If, for example, the sash does not have a proper seal on the sealing strips, the seal can be adjusted after loosening at least two fastening elements that hold the locking mechanism firmly connected to the guide rail.

According to a further feature of the innovation, it is advantageous that the locking engagements are held on the guide rail in such a way that the peripheral shape of one locking engagement is adapted to the inner region of the guide rail and in the case of the other locking engagement the inner region encompasses the outer section of the guide rail.

The advantage here is that no additional component is required to hold the locking engagements on the guide rail, but only the shape is adapted to suit the respective guide rail.

In order to further improve the locking engagements, the innovation provides that a circumferential run-in slope is provided on the recesses of the locking engagements and that the recess has a slope at the end shown on the inside.

In any case, a perfect entry of the bolt into the respective bolt engagement is guaranteed, whereby the bevel shown on the inside should also ensure the necessary pressure of the sash.

Another feature of the innovation is that the locking engagements have clearances to reduce the amount of material used and are therefore more cost-effective to manufacture, and that the locking engagements are made of plastic, preferably a cast material, so that all functional features of the locking engagement are formed in a one-piece design. Furthermore, the design of the shape is simple to manufacture and can be implemented in any way, particularly in the case of the locking engagements that are held so that they can move on the guide rail, since these locking engagements are also visible in the locked position.

Further advantages of the innovation emerge from the description and the drawing, which are described in more detail using several embodiments shown in the drawing.

It shows:

Fig. 1 the closing end of a lift-sliding sash with associated fixed frame in plan view,

Fig. 2 a plan view of the front side of the closing end of this wing,

Fig. 3 a sectional view of the upper closing end of the lifting-sliding sash of the fitting,

Fig. 4a the upper closing end of this wing in raised, opened

Position,
30

Fig. 4b is a corresponding plan view according to Fig. 4a,

Fig. 5a the upper closing end of this wing in lowered closing position,

•
• ··· ·
•
• •
• •
• •
« *·
*
· · · •
··· •
• •
••t •
♦ ·· •
·· •
·%

Fig. 5b a corresponding representation in plan view with lowered wing according to Fig. 5a,

Fig. 6a

and 6b a representation corresponding to Fig. 4a and 4b of a second embodiment, with a different guide rail,

Fig. 7a

and 7b a representation corresponding to Fig. 5a and 5b of the embodiment according to Fig. 6a and 6b,

Fig. 8a

and 8b shows a representation corresponding to Fig. 4a and 4b of a further

embodiment,
15

Fig. 9a

and 9b a representation corresponding to Fig. 5a and 5b of the embodiment according to Fig. 8a and 8b,

Fig. 10 is a plan view of the closure device,

Fig. 11 is a plan view of Fig. 10 with pre-assembled individual parts of the locking device and

Fig. 12 is a list of design variants that are used according to the embodiments.

In a fixed frame 1, a wing 2 can be lifted in the direction of arrow 3 and then moved in the direction of arrow 4, with arrow 4 symbolizing the opening direction. The wing is lifted in a known manner by means of an actuating element 5 designed as a handle, which is pivoted in the direction of arrow 6 for this purpose. The rotary movement is transmitted to a drive rod 8 in particular via an actuating rod 7 of known design. The fastening rod 7 is also coupled in a known manner to a front carriage 10 via a lower corner deflection 9. A connecting rod 11 leads to a second or rear carriage.

If the drive rod 8 is moved upwards in the direction of arrow 12 of the sliding direction by means of a rotary movement 6 of the actuating element 5, this causes the carriage to be moved relative to the lower end of the sash in the sliding direction of arrow 13. A known pushing device connected between the carriage and the lower end of the sash, for example with tabs or lifting cams, simultaneously causes the sash to be raised in the direction of arrow 3 of the lifting direction relative to the carriage or the fixed frame 1.

The sash is sealed at its lower end against the fixed frame, for example by two sealing strips 14 and 15 embedded in the lower cross member, whereby in the embodiment these sealing strips are pressed sealingly against the horizontal legs of a guide rail 16. When the sash is lowered, upper sealing strips 17 and 18 are pressed against the associated profile end of an upper guide rail 19. Corresponding sealing strips are also located on the vertical members. If the sash is initially only raised, i.e. moved along its plane, the lower and upper sealing strips 14, 15, 17 and 18 are released, but the sealing strips on the vertical members remain under tension. Accordingly, both raising and lowering the sash in a pure lifting and lowering movement within the sash plane is associated with a correspondingly strong friction. This can be so strong that a tall, narrow and light sash will not lower itself under its own weight when its lowering stroke is released. Furthermore, with narrow and light sashes in locking position 58, it is also possible to lift the sash 2 and lift it out accordingly. In order to counteract this possibility, but at the same time to provide all variants according to Fig. 12 with increased burglary protection while simultaneously forcing the sash to be lowered, the new locking device 20 is installed, for example, on the upper end of the sash on the locking side and, depending on the variant, the locking engagements 25, 47 and 48 provided for this have been designed.

Essential elements of this locking device 20 are, in addition to the already mentioned and usually at this point, i.e. in particular on the closing-side wing vertical beam, the existing drive rod 8, a guide part 30, a locking engagement 25 according to one of the embodiments and finally, according to Fig. 3, the locking device 20 itself. The actuating rod 7 has at its upper end in the direction of the locking device 20 a coupling shoe 42 which is connected to the drive rod

8 of the actuating rod 7 is in a positive connection and for further transmission of the stroke to the locking device 20, a connecting element 37, for example in the form of a square pin, which consists of at least one fastening means 43, but preferably of two fastening means 43 as shown in Fig. 3. The readjustment and fastening of the connecting element 37 takes place via the fastening means 43 which can be actuated through a clearance 63 of the faceplate profile 64.

The end of the locking device 20 pointing towards the actuating rod 7 also has a coupling shoe 35, whereby the connecting element 37 can be adjusted and fastened by means of two fastening elements 36, as in the actuating rod 7, through a clearance 62 in the faceplate profile 28. In order to cover the interface between the locking device 20 and the actuating rod 7 as far as possible, a cover 31 is provided which is designed to be long enough that even an inaccurate interface of the actuating rod 7 can be covered in any case. By transferring the lifting movement of the actuating rod 7 via the connecting element 37 to the sliding element 27, which has a toothing 40, a reversing pinion 34 is provided which holds a drive rod section 22 to which a bolt 23 is fastened so that it can be moved in the opposite direction. If, for example - as shown in Fig. 3 - the locking device 20 is in the open sliding position and the wing is to be brought into a lowered locking position 58, the drive rod of the actuating rod 7 moves in the direction of the carriage 10 and the drive rod section 22 of the locking device 20 in the arrow sliding direction 12, whereby the bolt 23 is then in engagement with the bolt engagement 25. In order to achieve the best possible inclusion in the bolt engagement 25, a run-in slope 55, 55', 55" and a run-in slope 45 on the bolt 23 are provided, as is the case with the bolt engagements 47 and 48 in the exemplary embodiments.

Finally, in the recess of the locking engagement 25, 47 and 48 there is a bevel 56, 56' and 56", which causes a corresponding tightening of the wing 2 to the frame 1. An upper locking-side guide part 30 ensures that the wing 2 is guided and held on the frame 1. The locking device 20 is designed in the area of the guide part 30 by means of a clearance 29 so that the clearance

ensures early adjustment or fixation until finally the closure device 20 is firmly connected to the guide part 30 by means of a fastening means 44.

Fig. 4a and 4b show the upper locking-side section of the locking device 20 with one of the locking engagements 47 in the open position, whereby the actuating member is rotated by 180° and the sash 2 is held in a raised position so that it can be moved over one of the guide rails 46. In Fig. 4b it can be seen that the peripheral shape 50 of the locking engagement 47 is adapted to the inner region 52. The further shape of the locking engagement 47 is freely selectable and can be adapted to the design of the window or door due to the visible area. From Fig. 4a it can be seen that the locking engagement 47 is provided with clearances 57 which on the one hand contribute to saving material, which means that the material or the locking engagement 47 itself is cost-effective to manufacture and on the other hand the strength is increased depending on the choice of material.

The design shown in Fig. 5a and 5b is the locking position 58 of the design variant shown in Fig. 4a and 4b. The contact edge 26 of the locking engagement 47 is essential here, as it helps to forcibly lower the sash 2 against the frame 1. The locking engagement 47 can be precisely positioned and secured in the guide rail 46 using the fastening means 49. The locking engagement 47 can also be released accordingly using the fastening means 49 if, for example, the position of the sash 2 has to be changed due to the sealing.

In Fig. 6a and 6b, as well as in Fig. 7a and 7b, a further embodiment is shown which differs from Fig. 4a and 4b or Fig. 5a and 5b in that the locking engagement 25 is adapted to a different guide rail 19. Fig. 6b shows that the outer section 53 of the guide rail 19 is encompassed by the inner region 51 of the locking engagement 25 and is clamped and held in position by the fastening means 49. The design of the locking engagement 25 also has clearances 57 which, as with the locking engagement 47, contribute to the material or the locking engagement 25 itself being cost-effective to manufacture and, depending on the choice of material, the strength is increased.

In the illustrated embodiment according to Fig. 8 a and 8b or according to Fig. 9a and 9b, a further locking engagement 48 has been designed, which is attached to the vertical wing spars

24 is attached directly in order to finally cover all the design variants shown in Fig. 12. The locking engagement 48 also has the recess 54" as well as the inlet slope 55", the slope 56" and the clearance 57". The advantage here is that the locking device 20 is used for all the design variants shown in Fig. 12 without any changes and that therefore only the locking engagements have to be adapted accordingly.

As can be seen in particular from Fig. 11, individual functional components of the locking device 20 are pre-assembled in bearing plates 41. The flanged bushings 59 are designed in such a way that, for example, the sliding element 27 and also the reversing pinion 34 can be moved freely between the bearing plates 41. In order to offer as much resistance as possible in the event of a possible break-in attempt, the reversing pinion is mounted in the bearing plates 41, which are made of a solid material. In addition, the flanged bushings 59 have an opening 60 through which the pre-assembled functional component shown in Fig. 11 is fixed by means of dowel pins 61 in the overall component according to Fig. of the locking device 20 on the faceplate profile 28 transversely to the direction of movement of the locking device 20 and fastened, for example, by riveting.

Applicant: SIEGENIA-FRANK KG, : .· . 2 · ·
· * *
... · *·· ··· ■ · · ·
... ··♦ 57074 Siegen, Germany S199127G ANO.: 1 004 808 Eisenhüttenstrasse 22, 5

10 LIST OF REFERENCE SYMBOLS

1 Frame -2-
··· ···· ·· ·· *· ·· **
φ · · #·········
····· · · · · · · · ·
• · · · ······ » m ·
··· « #····
··· ···· ···· ·· ·· ···· ·· ·« ·· · · · ·
····· ····
······ ·* *
• · ··♦···· · · ·
· · · · · ·
·· ·· ·· ··· 2 wing 3 Lifting direction L5 4 Opening direction 5 Actuator 6 rotational movement 7 Operating linkage 8th Drive rod 20 9 Corner deflection 10 Carriage 11 Connecting rod 12 Sliding direction 13 Sliding direction 25 14 Sealing strip 15 Sealing strip 16 Track 17 Sealing strip 18 Sealing strip 30 19 Guide rail 20 Locking device 21 fitting 22 Drive rod section 23 bars

24 ,54' vertical wing spar 25 '55' Latch engagement 26 ,56' Investment edge 27 ,57' Sliding element 5 28 Faceplate profile 29 Clearance 30 Guide part 31 cover 32 cross-section 10 33 cross-section 34 Reversing pinion 35 Clutch shoe 36 Fasteners 37 Connecting element 15 38 L-shaped 39 Long hole 40 Gearing 41 Bearing plate 42 Clutch shoe 20 43 Fasteners 44 Fasteners 45 Inlet slope 46 Guide rail 47 Latch engagement 25 48 Latch engagement 49 Fasteners 50 Circumferential shape 51 inner area 52 inner area 30 53 outer section 54 ,54" recess 55 ,55" inlet slope 56 ,56" slope 57 ,57" clearance 35 58 Locking position :··.:··· .··.."..*·. .··..". ·····'*::. : : · : : :·· .· ·..: ·..: 4 ···:··: ··:· : : j..*:... ·&iacgr;·. ··* ··* .. ·

• ■ · ·

59 collar bushing 60 breakthrough 61 Clamping pins 62 Clearance 63 Clearance 64 Faceplate profile

Claims (18)

1. Fitting ( 21 ) of an at least liftable, but preferably also movable wing ( 2 ) of a window or a door, with a guide rail ( 19 , 46 ), wherein an actuating rod ( 7 ) is located on the wing ( 2 ), which has a drive rod ( 8 ) which can be moved downwards by means of an actuating member ( 5 ) to lower the wing ( 2 ), characterized in that the fitting ( 21 ) has a locking device ( 20 ) which can be coupled to the actuating rod ( 7 ) and has a drive rod section ( 22 ) which can be moved against the drive rod ( 8 ) of the actuating rod ( 7 ), wherein a latch ( 23 ) is provided on the drive rod section ( 22 ) which in the locking position ( 58 ) engages with a Latch engagement ( 25 , 47 , 48 ) and rests against a contact edge ( 26 ) of the latch engagement ( 25 , 47 , 48 ) and that the latch engagement ( 25 , 47 , 48 ) is directly assigned to one of the guide rails ( 19 , 46 ). 2. Fitting ( 21 ) according to claim 1, characterized in that the locking device ( 20 ) has a faceplate profile ( 28 ) which is essentially U-shaped and accommodates all components of the locking device ( 20 ). 3. Fitting ( 21 ) according to at least one of claims 1 to 2, characterized in that a clearance ( 29 ) for receiving a guide part ( 30 ) is provided on the faceplate profile ( 28 ) at the end facing the guide rail ( 19 , 46 ) and is firmly connected to the guide part ( 30 ) by means of a fastening means ( 44 ). 4. Fitting ( 21 ) according to at least one of claims 1 to 3, characterized in that the faceplate profile ( 28 ) has a cover ( 31 ) of the end pointing in the direction of the actuating rod ( 7 ). 5. Fitting ( 21 ) according to at least one of claims 1 to 4, characterized in that the faceplate profile ( 28 ) is divided into two cross sections ( 32 , 33 ), one cross section ( 32 ) serving to guide the drive rod section ( 22 ) and the other cross section ( 33 ) receiving a number of parts of the locking device ( 20 ), including a sliding element ( 27 ) which is guided and held in the cross section ( 32 ). 6. Fitting ( 21 ) according to at least one of claims 1 to 5, characterized in that the sliding element ( 27 ) is held in constant drive connection with the drive rod section ( 22 ) by at least one reversing pinion ( 34 ). 7. Fitting ( 21 ) according to at least one of claims 1 to 6, characterized in that the sliding element ( 27 ) carries at one end a coupling shoe ( 35 ) with two fastening means ( 36 ) for receiving a connecting element ( 37 ) and the other end is L-shaped ( 38 ), wherein one side has an elongated hole ( 39 ) for guiding the reversing pinion ( 34 ) and the other side contains a toothing ( 40 ). 8. Fitting ( 21 ) according to at least one of claims 1 to 7, characterized in that the locking device ( 20 ) has two bearing plates ( 41 ) onto which a certain number of individual parts of the locking device ( 20 ) can be pre-assembled in order to then subsequently install them in the locking device ( 20 ). 9. Fitting ( 21 ) according to claim 8, characterized in that at least two flange bushings ( 59 ) with an opening ( 60 ) are used to fasten the bearing plates ( 41 ) with the pre-assembled individual parts in order to fix the bearing plates ( 41 ) with the pre-assembled individual parts to the faceplate profile ( 28 ) by means of at least two clamping pins ( 61 ) after insertion and adjustment of the bearing plates (41). 10. Fitting ( 21 ) according to at least one of claims 1 to 9, characterized in that a coupling shoe ( 42 ) is mounted on the end of the actuating rod ( 7 ) pointing towards the locking device ( 20 ), which coupling shoe has two fastening means ( 43 ) in order to be able to receive and fasten the connecting element ( 37 ). 11. Fitting ( 21 ) according to claim 1, characterized in that the latch ( 23 ) is preferably manufactured as a stamped and bent part. 12. Fitting ( 21 ) according to claim 1, characterized in that the bolt ( 23 ) has a run-in slope ( 45 ). 13. Fitting ( 21 ) according to claim 1, characterized in that the locking engagements ( 25 , 47 ) are held displaceably on the respective guide rails ( 19 , 46 ). 14. Fitting ( 21 ) according to claim 13, characterized in that the peripheral shape ( 50 ) of one locking engagement ( 47 ) is adapted to the inner region ( 52 ) of the guide rail ( 46 ), and in the case of the other locking engagement ( 25 ) the inner region ( 51 ) encompasses the outer section ( 53 ) of the guide rail ( 19 ). 15. Fitting ( 21 ) according to at least one of claims 13 to 14, characterized in that the locking engagement ( 25 , 47 ) has at least one fastening means ( 49 ), preferably two fastening means ( 49 ), which hold the locking engagement ( 25 , 47 ) on the guide rail ( 19 , 46 ) in a fixed connection. 16. Fitting ( 21 ) according to one or more of claims 1 to 15, characterized in that the locking engagements ( 25 , 47 , 48 ) have a recess ( 54 , 54 ', 54 ") which has a circumferential run-in slope ( 55 , 55 ', 55 ") towards the outward-facing end and has a slope ( 56 , 56 ', 56 ") at the inward-facing end. 17. Fitting ( 21 ) according to one or more of claims 1 to 16, characterized in that the locking engagements ( 25 , 47 , 48 ) have clearances ( 57 , 57 ', 57 ") for reducing material. 18. Fitting ( 21 ) according to one or more of claims 1 to 17, characterized in that the locking engagements ( 25 , 47 , 48 ) are made of plastic, preferably of a cast material.