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Patent Searching and Data


Title:
A SPACER PROFILE WITH SEALING ELEMENT
Document Type and Number:
WIPO Patent Application WO/2022/269029
Kind Code:
A1
Abstract:
A spacer profile (1) extending in a longitudinal direction Z and comprising a spacer body (10), where said spacer body (10) comprises an inner wall (11) being perpendicular to the longitudinal direction Z, an outer wall (12) and two side walls (13, 14) and two outer connection walls (15, 16), the inner wall (11), the outer wall (12), the two side walls (13,14) and the two outer connection walls together forming a chamber (50) suitable for a desiccant. The spacer profile (1) further comprises a sealing element (100) for keeping the primary sealant out of the intervening space in an insulating glass unit. The sealing element is in form of an elongated appendix and being part of the profile body.

Inventors:
PEDERSEN PETER (DK)
Application Number:
PCT/EP2022/067321
Publication Date:
December 29, 2022
Filing Date:
June 24, 2022
Export Citation:
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Assignee:
ROLLTECH AS (DK)
International Classes:
E06B3/663
Foreign References:
DE202016008421U12017-11-16
US20130305656A12013-11-21
DE102011011549A12012-08-23
DE3321878A11984-12-06
US5512341A1996-04-30
Attorney, Agent or Firm:
CHAS. HUDE A/S (DK)
Download PDF:
Claims:
CLAIMS

1. A spacer profile (1) extending in a longitudinal direction Z and comprising a spacer body (10), said spacer body comprising:

- an inner wall (11) having a first width, said inner wall being perpendicular to the longitudinal direction Z,

- an outer wall (12) having a second width, said outer wall and said inner wall being separated by a first distance d1,

- two sidewalls (13, 14) having a height h, said two sidewalls being separated by a second distance d2,

- the inner wall (11), the outer wall (12) and the two side walls (13, 14) together are forming a chamber (50) suitable for containing a desiccant,

- optionally the spacer body further comprises two outer connection walls (15, 16) extending between said two side walls (13, 14) and said outer wall (12) such that the inner wall (11), the outer wall (12), the two side walls (13, 14) and the outer connection walls (15, 16) together are forming the chamber (50) suitable for containing a desiccant,

- optionally the spacer body further comprises two inner connection walls (17, 18) extending between said two side walls (13, 14) and said inner wall (11) such that that the inner wall (11), the outer wall (12), the two side walls (13, 14) and the inner connection walls together (17, 18) are forming the chamber (50) suitable for containing a desiccant; wherein spacer profile (1) further comprises a sealing element (100) characterized in that the sealing element (100) is in form of an elongated appendix (104) wherein:

- said elongated appendix (103) is connected to the spacer body at a position being no more than 1/3 of the first distance d1 away from the inner wall (11)

- said elongated appendix (103) extends in a direction from the inner wall and outwardly and forming an angle a with an extension line of the side wall between 2 and 80 degrees

- said elongated appendix (103) has a length L1 being no more than ½ of the height h of the side walls (13, 14).

2. A spacer profile according to claim 1, wherein the elongated appendix is connected to the spacer body at the position of the inner wall.

3. A spacer profile according to claim 1 or 2, wherein said spacer body (10) further comprises a groove (104).

4. A spacer profile according to claim 3, wherein the groove (104) has a length L2 being larger than the length L1.

5. A spacer profile according to claims 1-4, wherein the spacer profile further comprises a diffusion barrier (60).

6. A spacer profile according to claim 5, wherein the diffusion barrier (60) is made of a polymeric material optionally sputtered with SiOx, where X is a number from and including 0 up to and including 2.

7. A spacer profile according to claim 6, wherein the diffusion barrier (60) has a bending pattern comprising at least four bendings, where the first bending (61) is a bending of at least 80°, preferably at least 90° and/or a last bending (62) of 180° thereby forming two substantially parallel and overlapping layers.

8. A spacer profile according to claim 5, wherein the groove (104) is formed by the diffusion barrier (60) .

9. A spacer profile according to any one of the preceding claims, wherein at least part of the profile body is made of a polymeric material .

10. A spacer profile according to claim 9, wherein elongated appendix (103) and the profile body is made of the same polymeric material.

11. An IG unit comprising at least two panes (4, 5) arranged opposite to each other and spaced apart with a spacer frame thereby forming an intervening space (3) therebetween, said spacer frame is made from a spacer profile (1) comprising a spacer body (10), said spacer body (10) comprising:

- an inner wall (11) having a first width, said inner wall being perpendicular to the longitudinal direction Z,

- an outer wall (12) having a second width, said outer wall (12) and said inner wall (11) being separated by a first distance d1 ,

- two side walls (13, 14) having a height h, said two side walls (13, 14) being separated by a second distance d2,

- the inner wall (11), the outer wall (12) and the two side walls (13, 14) together are forming a chamber (50) suitable for containing a desiccant

- optionally the spacer body (10) further comprises two outer connection walls (15, 16) extending between said two side walls (13, 14) and said outer wall (12) such that the inner wall (11), the outer wall (12), the two side walls (13, 14) and the outer connection walls (15, 16) together are forming the chamber (50) suitable for containing a desiccant

- optionally the spacer body (10) further comprises two inner connection walls (17, 18) extending between said two side walls (13, 14) and said inner wall (11) such that that the inner wall (11), the outer wall (12), the two side walls (13, 14) and the inner connection walls (17, 18) together are forming the chamber (50) suitable for containing a desiccant

- a primary sealant (6), characterized in that the IG unit (2) further comprises a sealing element (100) positioned on and/or adjacent to an outer surface (32) of the side walls of the spacer body (10) said sealing element (100) is in form of an elongated appendix (103) wherein:

- said elongated appendix is connected to the spacer body at a position being no more than 1/3 of the first distance d1 away from the inner wall (11)

- said elongated appendix extends in a direction from the inner wall (11) and outwardly and forming an angle a with an extension line of the side wall between 2 and 80 degrees

- said elongated appendix has a length L1 being no more than ½ of the height h of the side walls (13, 14).

12. An IG unit comprising a spacer profile according to any one of claims 1- 9.

13. Use of a spacer profile according to any one of claims 1-9 in an IG unit.

14. A method for producing an IG unit comprising the steps of providing at least two panes bending a spacer profile into a spacer frame, wherein the spacer profile comprises a spacer body, said spacer body comprising: o an inner wall having a first width, said inner wall being perpendicular to the longitudinal direction Z, o an outer wall having a second width, said outer wall and said inner wall being separated by a first distance, o two side walls having a height h, said two side walls being separated by a second distance, o the inner wall, the outer wall and the two side walls together are forming a chamber suitable for containing a desiccant, o optionally the spacer body further comprises two outer connection walls extending between said two side walls and said outer wall such that the inner wall, the outer wall, the two side walls and the outer connection walls together are forming the chamber suitable for containing a desiccant, sealing the at least two panes to the spacer frame by means of a primary sealant, optionally fixing and/or further sealing with a secondary sealant, characterized in that the spacer body further a sealing element in form of an elongated appendix and is attached to the at least two panes, to the spacer profile or to the spacer frame in such a manner that the sealing element is positioned between the primary sealant and an intervening space formed by the spacer frame and the at least two panes.

Description:
TITLE

A spacer profile with sealing element

FIELD OF THE INVENTION

The present invention relates to a spacer profile with improved sealing for mounting between glass panes for forming an intervening space between said glass panes.

DESCRIPTION OF PRIOR ART

It is well known to provide spacer profiles in order to define the spacing between the panes of insulating glazing consisting of a plurality of parallel glass panes spaced by an insulating cavity.

Spacer profiles made of various materials and of various shapes are known in the art. Spacer profiles made by roll forming of a metal foil are widely used in the art and considered to be one of the preferred alternatives because of their stability and their low gas diffusion properties. Another type of widely used spacer profiles are hybrid spacer profiles having a profile body fully or partly made of a plastic material and provided with a foil made of materials such as metal, polymers or combinations thereof.

Insulating Glass Units (IG units) having a plurality of glass panes are made by automatic manufacturing machines. Spacer profiles are automatically bent to the desired size and shape and are arranged between two neighboring glass panes. Spacer profiles made of metal foils can be easily bent and will remain in the bent position.

Usually, a primary sealant is used between the sides of the spacer profile and the glass panes. Polyisobutylene (PIB) is the most common primary seal. The purpose of the primary seal is to make a gastight seal between the panes and the spacer. This is done to keep the gas inside the sealed space between the panes and the spacer and also to keep moisture out of the IG unit. The primary seal is usually supplemented with a secondary seal provided on the edge of the spacer and the glass panes so as to provide elastic structural bonding of the assembly. Solutions are seen, where the primary and the secondary sealant are the same component.

The primary sealant such as PIB has a limited adhesion property that can be used to hold the spacer in position during production, but the main purpose of the PIB is to maintain the gastight seal during stretching and compression as a result of pumping actions caused by sun and wind. However, when heated the PIB becomes less viscous and the pumping action of the panes causes the PIB to leak into the visible area of the IG unit. This phenomenon is known as creep. The problem with migration or creeping is increasing and it is expected that the global warming will add further to the problem.

Creep is not only an aesthetic problem. If it becomes too large, the IG unit must be changed, as there is a risk that the seal no longer is tight when the PIB is cooled during winter. If small pores are made when the butyl glue retracts then the gas between the panes can leak and/or humidity can enter the space between the panes.

The problem is of particular importance for bend profiles due to the traditional bending process. In the bending process mechanical support is applied to the sides of the spacer profile during the bending. Thereby it is secure that during the bending excess material does not enlarge the width of the spacer profile. This means that excess material is forced inwardly instead, and this can result is small cracks, pores or wrinkles on the outer side surface in the corners of the bend spacer profile. These, cracks, pores or wrinkles act as channels for the PIB during the pumping actions cause by sun and wind.

One attempt to solve this problem is to provide a groove in the spacer between the PIB and the interior of the IG unit. The groove functions as a reservoir, into which the PIB can expand when heated and from which it can retract when cooled. However, experience has shown that the reservoir becomes filled and thereafter the creep continues. Obvious solutions would be to increase the reservoir size and/or make additional reservoirs. Both solutions mean more complex profiles which increases production price and means increased risk of production errors. Thus, there is a need for a simpler solution that prevents the PIB from creeping into the visible area of the IG unit.

SUMMARY OF THE INVENTION

An object of the present invention is to solve the problem of PIB creep. More specifically, it is an object of the present invention to provide a spacer profile for mounting between glass panes for forming an intervening space between said glass panes, where the risk of PIB creep is significantly reduced. Further, it is an object of the present invention to provide an IG unit comprising at least two panes and a spacer profile, where the risk of PIB creep into the visible area of the IG unit is reduced. Finally, it is an object of the invention to provide a method for producing IG units comprising at least two panes and a spacer profile, where the resulting IG unit has a reduced risk of PIB creep into the visible area of the IG unit.

In general, the problem has been solved by adding a sealing element preferably positioned on or adjacent to the outer surface of the side walls of the spacer body of a spacer profile. With a sealing element is meant a construction which helps to prevent or limit the unintentional transition of a substance from one space to another. When the sealing element is used as described, it prevents or limits the PIB from creeping from the sealing position into the interior space of the IG unit.

According to the invention there is provided:

A spacer profile extending in a longitudinal direction Z and comprising a spacer body, said spacer body comprising:

- an inner wall having a first width, said inner wall being perpendicular to the longitudinal direction Z,

- an outer wall having a second width, said outer wall and said inner wall being separated by a first distance d1 ,

- two side walls having a height h, said two side walls being separated by a second distance d2,

- the inner wall, the outer wall and the two side walls together are forming a chamber suitable for containing a desiccant,

- optionally the spacer body further comprises two outer connection walls extending between said two side walls and said outer wall such that the inner wall, the outer wall, the two side walls and the outer connection walls together are forming the chamber suitable for containing a desiccant,

- optionally the spacer body further comprises two inner connection walls extending between said two side walls and said inner wall such that that the inner wall, the outer wall, the two side walls and the inner connection walls together are forming the chamber suitable for containing a desiccant, wherein the spacer profile further comprises a sealing element.

Preferably, the sealing element is positioned on and/or adjacent to an outer surface of the side walls or being or forming an overhang over the side walls. In a particularly suited embodiment the sealing element is in form of an elongated appendix, preferably of a synthetic material. The elongated appendix is connected to the spacer body at a position being no more than 1/3 of the first distance d1 away from the inner wall, preferably no more than 1/6 of the first distance d1 away from the inner wall. Preferably the elongated appendix is connected to the spacer body at the position of the inner wall.

Preferably the elongated appendix extends in a direction from the inner wall and outwardly and forming an angle a with an extension line of the side wall between 2 and 80 degrees, preferably between 3 and 60 degrees, more preferably between 5 and 45 degrees and most preferred between 10 and 40 degrees.

Preferably the distance between an extension line of the side wall and a line parallel therewith and touching the end of the elongated appendix is between between 0.05 and 1 mm, preferably between 0.1 and 0.8 mm and more preferably between 0.2 and 0.6 mm. By having the elongated appendix extending further out than the sidewalls the primary sealant is prevented from entering the interior of an IGU.

Preferably the elongated appendix has a length L1 being no more than ½ of the height h of the side wall, preferably no more than 1/3 of the height h of the side walls and most preferred no more that ¼ of the height h of the side walls.

The advantages of this combination of the length L1 of the elongated appendix, the position at which it is attached to the spacer body and the angle are multiple:

Firstly, during bending the elongated appendix will be squeezed towards the side wall of the spacer body during bending, but is will reposition itself after the bending and thereby cover any cracks, pores or wrinkles formed during the bending. Thus, it will improved the sealing in the bend regions of the spacer body.

Secondly, it leaves room on the side walls for the primary sealant and forms a barrier between the primary sealant and the intervening space between the panes. Thereby butyl creep is prevented during the pumping actions caused by sun and wind. Thirdly, the elongated appendix will always follow the panes and their movement during pumping actions and thereby a tight connection is kept.

Fourthly, a sharp uniform surface is visual from the outside, when looking into the IGU unit because no sealant is visible. Further, no metal, when used, will be visible as well. This is desired by customers

In a particular suited embodiment the elongated appendix is combined with a groove positioned behind the elongated appendix. Preferably the groove has a length L2 being larger than the length L1.

The advantage of the combination of the elongated appendix and the groove is that the groove will function as a reservoir capable of store the butyl that might migrate during the pumping actions cause by sun and wind.

It is to be noted that the primary sealant usually will be put on the side wall and not on the elongated appendix. Thus any migrating primary sealant will be stopped by the elongated appendix and forced into the groove thereby keeping the visible area of the IG unit free from primary sealant.

When the groove has a length L2 being larger than the length L1 of the elongated appendix the elongated appendix can flip into the groove during the bending operation and thereby provide further protection of the elongated appendix during bending. After the bending operation the elongated appendix returns to its original position.

Preferably the synthetic material of elongated appendix is same synthetic material that is used for the spacer body.

Preferably the synthetic material of the elongated appendix is selected from the group consisting of: polyolefins such as polyethylene, polypropylene and polyethylene terephthalate; polyamides, polyesters, ethylene-vinyl acetate, polycarbonates, ABS, SAN, PCABS. Co-polymers of the mentioned polymers can also be used When referring to the inner or outer surface of the inner wall, the outer wall, the side walls, the outer connection walls or the inner connection walls, respectively, the inner surface is the surface towards the chamber and the outer surface is the surface opposite to the chamber. The spacer body can be made of various materials such as metals, polymers and/or combinations thereof.

The spacer body can be in form of a folded metal sheet, in which case the spacer body is exclusively made of metal, such as aluminum and stainless steel. Upon such a spacer body, a sealing element can be attached by use of an adhesive.

Alternatively, the spacer body can be made of a polymeric material, where the sealing element can either be attached to or be an integral part of the spacer body. An integral part is to be understood as the sealing element being molded/extruded/co-extruded together with the spacer body so that it is a continuous part of the spacer body.

In another variant the spacer body is a hybrid materiel comprising both polymeric material, reinforcements made of metal and optionally diffusion barriers made of metal or polymeric foils.

In a preferred embodiment the spacer body is be made of a polymeric material, where the elongated appendix is either be attached to or be an integral part of the spacer body. An integral part is to be understood as the sealing element being molded/extruded/co- extruded together with the spacer body so that it is a continuous part of the spacer body

In general, spacer profiles comprising spacer bodies made of thin walled stainless steel, plastic or hybrid materials are known as warm edge profiles. The invention is suitable for all types of warm edge profiles.

In preferred embodiments, the inner wall comprises opening so that there can be communication between the chamber and the intervening space of the IG unit. Thereby, the desiccant can remove any moisture entering the intervening space.

In variants, the chamber defined by the inner wall, the outer wall, the side walls and optionally inner connection walls and/or outer connection walls can be further divided into smaller chambers. This can be done by applying separation walls in the chamber. The separation walls have the advantage that they can support the structure of the spacer body and/or during use of multiple desiccants and keep them separated. In one embodiment, the sealing element is in form of an adhesive polymer. In a preferred embodiment, the sealing member in form of an adhesive polymer has an elongated shape with a rectangular, trapezoid or parallelogrammical cross section. It is particularly preferred that the adhesive polymer is positioned on the outer surface of the side walls of the spacer body but in a way leaving part of the outer surface of the side walls free so that the primary sealant can be applied there. In a preferred version, the adhesive polymer is positioned on the outer surface of the side walls in such a way that at least 1/6 of the surface is free, preferably more that 1/3 of the of the surface is free, even more preferred ½ of the surface is free, particularly it is preferred that ¾ of the surface is free and especially preferred 5/6 of the surface is free. This leaves room for the primary sealant to be positioned on the outer surface of the side walls and below the sealing element made of an adhesive polymer.

In an alternative embodiment, the sealing element in form of an adhesive polymer is in form of a shoulder joining the inner wall of the spacer body of the spacer profile. The shoulder extends from the inner wall and at least down to 1/3 of the height of the side walls, preferably at least down to 1/6 of the height of the side walls.

The sealing element in form of an adhesive polymer can be used on both a space profile made of folded metal, on spacer profiles made of a polymeric material and on hybrid spacer profiles made of a combination of a polymeric material and metals.

Particularly suited adhesive polymers are made of polyamides, polyesters, ethylene-vinyl acetate, polyurethanes, and a variety of block copolymers and elastomers such as butyl rubber, ethylene-propylene copolymer, styrene-butadiene rubber and EDPM rubbers.

In another embodiment, the sealing element is in form of an elongated body with a rectangular, trapezoid or parallelogrammical cross section made of a first polymeric material. At least one of the sides of said elongated body is provided with an adhesive.

Preferred polymers for the first polymeric material are polymeric foams, natural rubbers, synthetic rubbers and EDPM rubbers. Suitable polymeric foams are foams such as a polyurethane foam or a polyisocyanurate foam. Preferred adhesives are epoxies, polyurethanes, polyimides.

According to the invention, there is further provided an IG unit comprising at least two panes arranged opposite to each other and spaced apart with a spacer frame thereby forming an intervening space therebetween, said spacer frame is made from a spacer profile comprising a spacer body, said spacer body comprising:

- an inner wall having a first width, said inner wall being perpendicular to the longitudinal direction Z,

- an outer wall having a second width, said outer wall and said inner wall being separated by a first distance d1 ,

- two side walls having a height h, said two side walls being separated by a second distance d2,

- the inner wall, the outer wall and the two side walls together are forming a chamber suitable for containing a desiccant,

- optionally the spacer body further comprises two outer connection walls extending between said two side walls and said outer wall such that the inner wall, the outer wall, the two side walls and the outer connection walls together are forming the chamber suitable for containing a desiccant,

- optionally the spacer body further comprises two inner connection walls extending between said two side walls and said inner wall such that that the inner wall, the outer wall, the two side walls and the inner connection walls together are forming the chamber suitable for containing a desiccant,

- a primary sealant, wherein the IG unit further comprises a sealing element sealing element is in form of an elongated appendix wherein:

- said elongated appendix is connected to the spacer body at a position being no more than 1/3 of the first distance d1 away from the inner wall

- said elongated appendix extends in a direction from the inner wall and outwardly and forming an angle a with an extension line of the side wall between 2 and 80 degrees

- said elongated appendix has a length L1 being no more than ½ of the height h of the side walls.

In a preferred embodiment, the sealing element in the IG unit is in form of an adhesive polymer. In a preferred embodiment, the sealing member in form of an adhesive polymer has an elongated shape with a rectangular, trapezoid or parallelogrammical cross section. It is particularly preferred that the adhesive polymer is positioned on the outer surface of the side walls of the spacer but in a way leaving part of the outer surface of the side walls free so that the primary sealant can be applied there. In a preferred version the adhesive polymer is positioned on the outer surface of the side walls in such a way that at least 1/6 of the surface is free, preferably more than 1/3 of the of the surface is free, even more preferred ½ of the surface is free, particularly it is preferred that ¾ of the surface is free and especially preferred 5/6 of the surface is free. This leaves room for the primary sealant to be positioned on the outer surface of the side walls and below the sealing element made of an adhesive polymer.

In another embodiment of the IG unit, the sealing element is in form of an elongated body with a rectangular, trapezoid or parallelogrammical cross section made of a first polymeric material. At least one of the sides of said elongated body is provided with an adhesive. Suitable materials for the first polymeric material are polymeric foams, natural rubbers, synthetic rubbers and EDPM rubbers. Suitable polymeric foams are foams such as a polyurethane foam or a polyisocyanurate foam.

According to the invention, there is further provided a method for producing IG units comprising the steps of:

Providing at least two panes

Bending a spacer profile into a spacer frame, wherein the spacer profile comprises a spacer body, said spacer body comprising: o an inner wall having a first width, said inner wall being perpendicular to the longitudinal direction Z, o an outer wall having a second width, said outer wall and said inner wall being separated by a first distance, o two side walls having a height h, said two side walls being separated by a second distance, o the inner wall, the outer wall and the two side walls together are forming a chamber suitable for containing a desiccant, o optionally the spacer body further comprises two outer connection walls extending between said two side walls and said outer wall such that the inner wall, the outer wall, the two side walls and the outer connection walls together are forming the chamber suitable for containing a desiccant, sealing the at least two panes to the spacer frame by means of a primary sealant, optionally fixing and/or further sealing with a secondary sealant,

- wherein a sealing element in form of an elongated appendix is attached to the at least two panes, to the spacer profile or to the spacer frame in such a manner that the sealing element is positioned between the primary sealant and an intervening space formed by the spacer frame and the at least two panes.

Preferably, the sealing element is attached to the at least two panes, to the spacer profile or to the spacer frame prior to the primary sealant. The advantage of attaching the sealing element prior to applying the primary sealant is that it decreases the risk of the primary sealant entering the intervening space i.e. the visible area of the IG unit.

The invention further relates to a particularly suited spacer profile.

The particularly suited spacer profile is extending in a longitudinal direction Z and comprising a spacer body, said spacer body comprising:

- an inner wall having a first width, said inner wall being perpendicular to the longitudinal direction Z,

- an outer wall having a second width, said outer wall and said inner wall being separated by a first distance d1 ,

- two side walls having a height h, said two side walls being separated by a second distance d2,

- two outer connection walls extending between said two side walls and said outer wall, where the inner wall, the outer wall, the two side walls and the two connection walls together are forming a chamber suitable for containing a desiccant, the spacer body further comprises a sealing element in form of an elongated appendix.

The particularly suited spacer profile may further comprise a diffusion barrier, where the diffusion barrier can be a barrier made of metal or a barrier made of a polymeric material. The diffusion barrier can be a single sheet, or it can be of multiple overlapping sheets.

Suitable polymeric diffusion barriers are made of materials such as ethylene-vinyl-alcohol copolymers (EVOH). Another suitable polymer-based diffusion barrier is made of polyethylene (PE) or polyethylene terephthalate (PET) preferably sputtered with a SiO x material where 0 £ X £ 2.

In a preferred version, at least part of the profile body is made of a polymeric material. Preferably, the polymeric material is a poor heat conduction. Suited polymeric materials can be selected from the group consisting of Polyolefins such as polypropylene or polyethylene terephthalate, polyamides, polycarbonates, ABS, SAN, PCABS. Co-polymers of the mentioned polymers can also be used.

In a preferred embodiment, the elongated appendix is made of a polymer selected from the group consisting of polyamides, polyesters, ethylene-vinyl acetate, polyurethanes. Alternatively, the elongated appendix can be made of a variety of block copolymers and elastomers such as butyl rubber, ethylene-propylene copolymer, styrene-butadiene rubber and EDPM rubbers. Particularly preferred are EDPM rubbers and polyamides.

In a preferred embodiment, the elongated appendix forms an overhang over the side walls.

Preferably, the profile body further comprises a groove in the side walls. The groove being positioned so that at least a part of the elongated appendix fits into the groove. The elongated appendix can then be partly pushed into the groove, when pressure is applied on the outer side. Thereby, a tight but flexible sealing is obtained, and the risk of the primary sealant, usually in form of PIB, creeping into the visible part of the IG unit is minimized.

Preferably, the elongated appendix is bendable so that it will bend towards the side walls, when light to moderate pressure is applied on the outside. With light to moderate pressure is understood the forces usually applied when mounting the spacer profile in an IG unit.

In a variant of the particularly suited spacer profile, the profile body is at least partly made of a polymeric material of the above kind, and the spacer profile comprises a diffusion barrier of metal being firmly bonded with the profile body. The diffusion barrier comprises at least four (4) bendings, where the first bending is a bending of at least 80°, preferably at least 90°. This combination provides a spacer profile that has suitable stiffness while still having very few wrinkles when bent into a frame during production of IG units. The diffusion barrier can also comprise a bending of 180° thereby forming two substantially parallel overlapping layers. This gives an increased stiffness and especially when combined with a first bending of at least 90°.

In a particularly suited variant the groove behind the elongated appendix is formed by the diffusion barrier.

LIST OF FIGURES

Fig. 1 is a schematic illustration of a spacer profile.

Figs. 2a-d are illustrations of the spacer profiles with various cross sections.

Figs. 3a-b illustrate spacer profiles with a sealing element.

Figs. 4a-b illustrate spacer profiles with a variant of the sealing element.

Fig. 5 illustrates a spacer profile with a sealing flange.

Fig. 6 illustrates a spacer profile with a sealing element in form of an elongated appendix. Fig. 7 illustrates an IG unit with a sealing element.

Fig. 8 illustrates an IG unit comprising a spacer profile with a sealing element in form of an elongated appendix.

Fig. 9 illustrates a spacer profile with a sealing element in form of an elongated appendix

Fig. 10 illustrates a spacer profile with a sealing element in form of an elongated appendix and a groove formed by the diffusion barrier

DESCRIPTION OF DRAWINGS

In figure 1 , a spacer profile 1 is illustrated. The spacer profile 1 comprises a profile body 10, where the profile body comprises an inner wall 11 and an outer wall 12 being separated from the inner wall 11 by a first distance d1. When mounted between the panes in an IG unit, the inner wall is facing towards the interior of the IG unit, i.e. the intervening space formed between the panes and the spacer. The profile body in figure 1 further comprises two side walls 13, 14. The side walls 13, 14 can be parallel to each other or they can be slightly slanted. The angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h. In figure 1, the inner wall and the outer wall are illustrated as being parallel, but that does not have to be the case. Solutions exist, where the inner wall and the outer wall are separated by a first distance d1 , and where they are slanted, curved etc. relative to each other. The inner wall 11, the outer wall 12 and the two side walls 13, 14 define a chamber 50, the chamber being suitable for containing a desiccant.

Figure 2 a-d illustrate a cross section of four different spacer profiles. In figure 2a, the spacer comprises a profile body 10 which comprises an inner wall 11 and an outer wall 12 being separated from the inner wall 11 by a first distance d1. The profile body 10 further comprises two sidewalls 13, 14 of a height h. Their orientation relative to the inner wall can be as described for figure 1. The two side walls 13, 14 are separated by a second distance d2. Together the inner wall 11, the outer wall 12 and the two side walls 13, 14 define a chamber 50 suitable for containing a desiccant. The side walls 13, 14 have an inner surface 31 and an outer surface 32, where the inner surface is the surface towards the chamber 50, and the outer surface 32 is the opposite side. Usually, the outer surface 32 is the place where a primary sealant such as PIB is applied, when the spacer profile is mounted in an IG unit.

The spacer profile in figure 2b differs from the spacer profile in figure 2a in that the spacer body 10 further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outer wall 12. Together the inner wall 11 , the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The outer connection walls can be straight as illustrated, but other shapes such as curved, concave, convex etc. can also be useable. As can be seen from figure 2b, the height h of the side walls are decreased, when the outer connection walls 13, 14 are present compared to the height of a the side walls, when the profile body does not comprise outer connection wall as illustrated in figure 2a.

The spacer in figure 2c differs from the spacer in figure 2a in that the spacer body 10 further comprises two inner connection walls 17, 18. The inner connection walls 17, 18 connect the sidewalls 13, 14 with the inner wall 11. Together the inner wall 11 , the outer wall 12, the two side walls 13, 14 and the two inner connection walls 17, 18 define a chamber 50 suitable for containing a desiccant. The advantage of the inner connection walls is that they provide a surface upon which a sealing element can be attached. Thus, a sealing element can be secured by both a part of the outer surface 32 of the connection walls and at least a part of the inner connection walls. The inner connection walls 17, 18 can be straight, curved, have a roughened outer surface, be corrugated or the like in order to improve the fixation properties. The fixation to the inner connection walls 17, 18 is illustrated in figures 4a and 4b.

The spacer in figure 2d differs from the spacer in figure 2a in that the spacer body 10 further comprises two outer connection walls 15, 16 and two inner connection walls 17, 18. The outer connection walls 15, 16 connect the side walls 13, 14 with the outer wall 12. The inner connection walls 17, 18 connect the side walls 13, 14 with the inner wall 11. Together the inner wall 11, the outer wall 12, the two side walls 13, 14, the two inner connection walls 17, 18 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The side walls 13, 14 have a height h.

Figures 3a-b illustrate the spacer from figure 2b with sealing elements 100. As is evident from figures 3a and 3b, the sealing elements could be attached to any one of the spacer profiles in figures 2a-d, and the sealing element could also be utilized together with other design variant of spacer profiles. Figure 3a illustrates a spacer profile 1 comprising a spacer body 10. The spacer body 10 comprises an inner wall 11 and an outer wall 12 being separated by a first distance d1. The profile body 10 further comprises two side walls 13, 14. The side walls 13, 14 can be parallel to each other, or they can be slightly slanted. The angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h. The profile body 10 further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outerwall 12. Together the inner wall 11 , the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The spacer profile 1 further comprises two sealing elements 100 attached to the sidewalls 13, 14 of the profile body 10. In the embodiment in figure 3a, the sealing elements 100 covers 1/3 of the height h of the outer surface 32 of the side walls. The sealing element 100 can be made of a single polymer, or it can be a composite material. Further, the sealing elements 100 can have inherent adhesive properties, or an adhesive can be applied to the surface being connected to the side walls 13, 14. When the spacer profile 1 is positioned in an IG unit, the primary sealant, typically PIB, is positioned on the outer surface 32 of the sidewalls 13, 14 and on the part of the outer surface of the sidewall 101 extending from the sealing element and towards the outer connection elements 15, 16. The primary sealant typically will extend onto the surface of the outer connection elements, where the primary sealant meets with a secondary sealant. In case on a primary sealing being used, it typically covers the outer surface of the outer wall. Figure 3b is a variant of figure 3a, where the sealing elements 100 covers ½ of the height h of the outer surface 32 of the side walls.

Figures 4a-b illustrate embodiments, where the sealing elements 100 are fixed at least to a part of the outer surface of the inner connection elements 15,16. Figure 4a illustrates a spacer profile 1 comprising a profile body 10, where the profile body 10 comprises an inner wall 11 and an outer wall 12 being separated by a first distance d1. The side walls 13, 14 can be parallel to each other or they can be slightly slanted. The angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h. The two side walls 13, 14 are separated by a second distance, and they have a height h. The spacer body 10 further comprises two outer connection walls 15, 16 and two inner connection walls 17,18. The outer connection walls 15, 16 connect the side walls 13, 14 with the outer wall 12. The inner connection walls 17, 18 connect the side walls 13, 14 with the inner wall 11. In the embodiment illustrated in figure 4a, the spacer profile further comprises two sealing elements 100, where the sealing element 100 is attached to at least a part of the outer surface of the inner connection walls 17,18 and being adjacent to the outer surface 32 of the side walls 13, 14. The advantage of using inner connection wall 17,18 for fixing the sealing element is that a long fixation surface can be obtained while maintaining the same height of the spacer and leaving more space on the outside of the side walls 13,14 for the primary sealant. Thereby, a better sealing can be obtained while still having sealing element 100 for keeping the primary sealant out of the interior of an IG unit. In the embodiment in figure 4a, the sealing element 100 roughly extends along the inner connection walls 17, 18 and to the point where the sidewalls 13,14 begin. This leaves alle the outer surface of the side wall 13,14 free for the primary sealant. The primary sealant can then be applied to the free area 101 of the outer surface 32 of the side walls 13, 14. The embodiment in figure 4b differs from the embodiment in figure 4a in that the sealing element extends 1/2 way down of the height h of the outer side 32 of the side walls 13, 14. In this way, the sealing element 100 forms a shoulder like structure on the outside of the profile body 10. The advantage of extending the sealing element down on the outer surface 32 of the side walls 13, 14 is that the sealing effect is increased so as to better keep the primary sealant out of the intervening spacer of the IG unit. The embodiment in figure 4b illustrates that the sealing element extends 1/2 of the height of the side walls. However other solutions such as 1/6, 1/3 or ¾ are contemplated.

Figure 5 illustrates an embodiment, where the sealing element 100 is an integral part of the profile body 10. The spacer profile 1 illustrated in figure 5 comprises a profile body 10, where the profile body comprises an inner wall 11 being perpendicular to the longitudinal direction Z and an outer wall 12 being separated from the inner wall 11 by a first distance d1. The profile body 10 further comprises two side walls 13, 14. As described earlier, the side walls 13, 14 can be parallel to each other or they can be slightly slanted. When slanted, the angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h

The profile body further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outer wall 12. Together the inner wall 11, the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The profile body 10 further comprises a sealing element 100, here in form of a sealing flange 102. In a suitable embodiment, the profile body is at least partly made of a first polymeric material, and the sealing flange can be of the same polymeric material, or in variants it can be of a second polymeric material. The spacer profile 1 may further comprise a diffusion barrier 60 firmly bonded with the profile body. The diffusion barrier 60 can be of a metal material, or it can be a polymeric material. In case of a polymeric material the barrier can be sputtered with SiO x where X can be any number from and including 0 up to and including 2. The spacer profile 1 can further comprise reinforcement elements such as a wire in the profile body, or the barrier material is bended so as to increase stiffness. A preferred solution is to use a diffusion barrier 60 made of a metal such as aluminium or stainless steel. Such a barrier can be bended so as to increase the stiffness of the spacer profile 1. A preferred bending pattern comprises at least four (4) bendings, where the first bending 61 is a bending of at least 80°, preferably at least 90°. Another preferred bending pattern comprises a 180° bend as the last bending 62 thereby forming two substantially parallel overlapping layers. An even more preferred bending pattern comprises a first bending 61 of at least 90° and a last bending 62 of 180° thereby forming two substantially parallel overlapping layers. The overlapping layers are not shown in the figure. The sealing flange 102 is illustrated as being positioned in level with the inner wall 11. However, other positions and extensions are possible. The sealing flange can be positioned in the first ½ of the height h of the side walls 13,14 measured from the inner wall 11. More preferred is a position within the first 1/3 of the height h measured from the inner wall 11. Preferably, the position and the width of the sealing flange leaves at least 1/6 of the outer surface 32 free, preferably more than 1/3 of the of the outer surface 32 is free, even more preferred is ½ of the outer surface 32 free, particularly it is preferred that ¾ of the outer surface 32 is free and especially preferred 5/6 of the outer surface 32 is free. The free area 101 of the outer surface can be used for sealing with the primary sealant when mounting the panes in the IG unit.

Figure 6 illustrates a variant of the spacer in figure 5. The spacer profile in figure 6 comprises a profile body 10, where the profile body comprises an inner wall 11 being perpendicular to the longitudinal direction Z and an outer wall 12 being separated from the inner wall 11 by a first distance d1. The profile body 10 further comprises two side walls 13, 14. As described earlier, the side walls 13, 14 can be parallel to each other or they can be slightly slanted. When slanted, the angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h. The profile body further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outer wall 12. Together the inner wall 11 , the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The profile body 10 further comprises a sealing element 100, here in form of an elongated appendix 103 extending from the profile body. In a preferred embodiment, the spacer profile 1 further comprises a groove 104 into which at least a part of the elongated appendix can fit. The profile body 10 is at least partly made of a first polymeric material and the elongated appendix can be of the same polymeric material, or in variants the elongated appendix can be of a second polymeric material. The spacer profile 1 further comprises a diffusion barrier 60 firmly bonded with the profile body. The diffusion barrier 60 can be of a metal material, or it can be a polymeric material. In case of a polymeric material, the barrier can be sputtered with SiO x where X can be any number from and including 0 up to and including 2. The spacer profile 1 can further comprise reinforcement elements such as a wire in the profile body, or the barrier material is bended so as to increase stiffness. A preferred solution is to use a diffusion barrier 60 made of a metal such as aluminium or stainless steel. Such a barrier can be bended so as to increase the stiffness of the spacer profile 1. A preferred bending pattern comprises at least four (4) bendings, where the first bending 61 is a bending of at least 80°, preferably at least 90°. Another preferred bending pattern comprises a 180° bend as the last bending 62 thereby forming two substantially parallel overlapping layers. An even more preferred bending pattern comprises a first bending 61 of at least 90° and a last bending 62 of 180° thereby forming two substantially parallel overlapping layers. The overlapping layers are not shown in the figure.

Figure 7 illustrates an IG unit 2 comprising a spacer profile 1 and two panes 4, 5 arranged with the spacer between them so as to keep a distance between the panes 4, 5 and thereby defining an intervening space 3. The spacer profile 1 comprises a profile body 10 comprising an inner wall 11 and an outer wall 12 being separated from the inner wall 11 by a first distance d1. The inner wall 10 is facing towards the intervening space 3 of the IG unit 2. The profile body 10 further comprises two side walls 13, 14. The side walls 13, 14 can be parallel to each other or they can be slightly slanted. The angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105° or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h. The profile body 10 further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outer wall 12. Together the inner wall 11, the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The IG unit 2 further comprises two sealing elements 100 attached to the sidewalls 13, 14 of the profile body 10 and/or to the panes 4,5. In the embodiment in figure 7, the sealing elements 100 covers 1/3 of the height h of the outer surface 32 of the side walls. The sealing element 100 can be made of a single polymer, or it can be a composite material. Further, the sealing elements 100 can have inherent adhesive properties, or an adhesive can be applied to the surface being connected to the side walls 13, 14. The IG unit further comprises a primary sealant 6 located on the outer surface 32 of the side walls and on the opposite side of the sealing member than the intervening space 3 of the IG unit. The IG unit 2 further comprises an optional secondary sealant 7.

Figure 8 illustrates an IG unit 2 comprising a spacer profile 1 as described in figure 6 and two panes 4,5 arranged with a spacer profile between them so as to keep a distance between the panes 4,5 and thereby defining an intervening space 3. The IG unit further comprises a primary sealant 6 located on the outer surface 32 of the side walls and on the opposite side of the sealing member than the intervening space 3 of the IG unit. The IG unit 2 further comprises an optional secondary sealant 7. When the panes 5,6 are being fixed in the IG unit 2, the elongated appendix 103 will bend towards the profile body and thereby forming a tight seal keeping the primary sealant 6 out the of intervening space 3.

Figure 9 illustrates an embodiment, where the sealing element 100 is an integral part of the profile body 10 an is in form of an elongated appendix 103 having a length L. The spacer profile 1 illustrated in figure 5 comprises a profile body 10, where the profile body comprises an inner wall 11 being perpendicular to the longitudinal direction Z and an outer wall 12 being separated from the inner wall 11 by a first distance d1. The profile body 10 further comprises two side walls 13, 14. As described earlier, the side walls 13, 14 can be parallel to each other or they can be slightly slanted. When slanted, the angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h

The profile body further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outer wall 12. Together the inner wall 11, the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The profile body 10 further comprises a sealing element 100, here in form of an elongated appendix 103. In a suitable embodiment, the profile body is at least partly made of a first polymeric material, and the sealing flange can be of the same polymeric material, or in variants it can be of a second polymeric material. The spacer profile 1 may further comprise a diffusion barrier 60 firmly bonded with the profile body. The diffusion barrier 60 can be of a metal material, or it can be a polymeric material. In case of a polymeric material the barrier can be sputtered with SiO x where X can be any number from and including 0 up to and including 2. The spacer profile 1 can further comprise reinforcement elements such as a wire in the profile body, or the barrier material is bended so as to increase stiffness. A preferred solution is to use a diffusion barrier 60 made of a metal such as aluminium or stainless steel. Such a barrier can be bended so as to increase the stiffness of the spacer profile 1. A preferred bending pattern comprises at least four (4) bendings, where the first bending 61 is a bending of at least 80°, preferably at least 90°. Another preferred bending pattern comprises a 180° bend as the last bending 62 thereby forming two substantially parallel overlapping layers. An even more preferred bending pattern comprises a first bending 61 of at least 90° and a last bending 62 of 180° thereby forming two substantially parallel overlapping layers. The overlapping layers are not shown in the figure. Elongated appendix 103 is illustrated as being positioned in level with the inner wall 11. However, other positions and extensions are possible. The elongated appendix 103 forms an angle a with the extension line 110 of the sidewalls 13, 14 between 2 and 80 degrees, preferably between 3 and 60 degrees, more preferably between 5 and 45 degrees and most preferred between 10 and 40 degrees.

The length L of the elongated appendix is no more than ½ of the height h of the side wall, preferably no more than 1/3 of the height h of the side walls and most preferred no more that ¼ of the height h of the side walls. Thereby, the position and the length of the elongated appendix 103 leaves at least 1/6 of the outer surface 32 free, preferably more than 1/3 of the of the outer surface 32 is free, even more preferred is ½ of the outer surface 32 free, particularly it is preferred that ¾ of the outer surface 32 is free and especially preferred 5/6 of the outer surface 32 is free. The free area 101 of the outer surface can be used for sealing with the primary sealant when mounting the panes in the IG unit and the elongated appendix prevents it from creeping into the interior of the IGU.

Figure 10 illustrates spacer profile which comprises a profile body 10, where the profile body comprises an inner wall 11 being perpendicular to the longitudinal direction Z and an outer wall 12 being separated from the inner wall 11 by a first distance d1. The profile body 10 further comprises two side walls 13, 14. As described earlier, the side walls 13, 14 can be parallel to each other or they can be slightly slanted. When slanted, the angle Q between the side walls 13, 14 and the inner wall 11 can be between 60° and 120°, preferably between 60° and 105°, or even more preferably between 75° and 105°. The two side walls 13, 14 are separated by a second distance d2, and they have a height h. The profile body further comprises two outer connection walls 15, 16. The outer connection walls 15, 16 connect the sidewalls 13, 14 with the outer wall 12. Together the inner wall 11 , the outer wall 12, the two side walls 13, 14 and the two outer connection walls 15, 16 define a chamber 50 suitable for containing a desiccant. The profile body 10 further comprises a sealing element 100, here in form of an elongated appendix 103 extending from the profile body. The elongated appendix 103 forms an angle a with the extension line 110 of the sidewalls 13, 14 between 2 and 80 degrees, preferably between 3 and 60 degrees, more preferably between 5 and 45 degrees and most preferred between 10 and 40 degrees.

The length L of the elongated appendix is no more than ½ of the height h of the side wall, preferably no more than 1/3 of the height h of the side walls and most preferred no more that ¼ of the height h of the side walls. Thereby, the position and the length of the elongated appendix 103 leaves at least 1/6 of the outer surface 32 free, preferably more than 1/3 of the of the outer surface 32 is free, even more preferred is ½ of the outer surface 32 free, particularly it is preferred that ¾ of the outer surface 32 is free and especially preferred 5/6 of the outer surface 32 is free

The profile body 10 is at least partly made of a first polymeric material and the elongated appendix can be of the same polymeric material, or in variants the elongated appendix can be of a second polymeric material. The spacer profile 1 further comprises a diffusion barrier 60 firmly bonded with the profile body. The diffusion barrier 60 can be of a metal material, or it can be a polymeric material. In case of a polymeric material, the barrier can be sputtered with SiO x where X can be any number from and including 0 up to and including 2. The spacer profile 1 can further comprise reinforcement elements such as a wire in the profile body, or the barrier material is bended so as to increase stiffness. A preferred solution is to use a diffusion barrier 60 made of a metal such as aluminium or stainless steel. Such a barrier can be bended so as to increase the stiffness of the spacer profile 1. A preferred bending pattern comprises at least four (4) bendings, where the first bending 61 is a bending of at least 80°, preferably at least 90°. Another preferred bending pattern comprises a 180° bend as the last bending 62 thereby forming two substantially parallel overlapping layers. An even more preferred bending pattern comprises a first bending 61 of at least 90° and a last bending 62 of 180° thereby forming two substantially parallel overlapping layers. The overlapping layers are not shown in the figure.

In the embodiment illustrated in figure 10 the spacer profile 1 further comprises a groove 104 with a length L2 into which the elongated appendix can fit. The groove 104 is formed by the diffusion barrier 60. Alternatively the groove 104 can be formed in the sidewall itself.

In the embodiment illustrated in figure 10 the extension line of the sidewalls 110 and a line being parallel therewith and touching the end of the elongated appendix is separated by a third distance d3. The third distance can be between 0.05 and 1 mm, preferably between 0.1 and 0.8 mm and more preferably between 0.2 and 0.6 mm.

REFERENCES

I - Spacer profile 2 - IG unit

3 - intervening space 4, 5 - panes

6 - primary sealant

7 - secondary sealant 10 - profile body

II - inner wall 12 - outer wall 13,14 - side walls

15,16 - outer connection walls 17,18 - inner connection walls

31 - inner surface

32 - outer surface 50 - chamber

60 - diffusion barrier

61 - first bending

62 - last bending

100 - sealing element

101 - area of outer surface

102 - sealing flange

103 - elongated appendix

104 - groove

110 - extension line of side walls

III - a line parallel with the extension line of the side walls and touching the end of the elongated appendix d1 - first distance d2 - second distance d3 - third distance

L1 - length of elongated appendix

L2 - length of groove a - angle between elongated appendix and the extension line of side walls h - height Q - angle