Section frame with thermal insulation between the inner and outer frame section
United States Patent 1191 Jacob [451 Apr. 22, 1975 1 1 SECTION FRAME WITH THERMAL INSULATION BETWEEN THE INNER AND OUTER FRAME SECTION [75] Inventor: Gernot Jacob, Deggendorf, Germany [73] Assignee: Gotz Metallbau GmbI-I,  
 Grosswa1ding, Germany 22 Filed: Apr. 9, 1973 2&#39;11 App1.No.:349,385  
 {30] Foreign Application Priority Data Apr. 13, 1972 Germany 2217877 July 28, 1972 Germany 2237245 [52] U.S. C1. 52/403; 52/616; 49/D1G. 1 [51] Int. Cl. E061) l/l8 [58] Field of Search 52/397, 398, 399, 400, 52/502, 616, 472, 403, 475, 494, 465, 466, 467, 468, 563, 564, 479, 481, 508; 49/DIG. 1  
 [56] References Cited UNITED STATES PATENTS 2,877,515 3/1959 Haas 52/398 X 3,114,219 12/1963 Bradley 52/396 Primary E.\&#39;aminerErnest R. Purser Assistant Examiner-Carl D. Friedman [57] ABSTRACT The invention concerns section frames with thermal insulation between the inner and outer frame section each of which is provided with pairs of opposite section grooves opening out at right angles to the plane of the frame, whereby section lugs pertaining to insulation sections connecting the frame sections with one another and clamped in&#39;the direction of the section grooves engage the said section grooves.  
 11 Claims, 11 Drawing Figures PATENTED 3.878.660  
 SdEET 1 [IF 3 FIG. 2 6  
 PATENTED PRZZIB S 3. 878.660  
 sum 2 OF 3 FIG. 4 F165 FIG. 6  
 PATENTEDAPRZZIQZE sum 3 I 3 FIG. 7  
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 SECTION FRAME WITH THERMAL INSULATION BETWEEN THE INNER AND OUTER FRAME SECTION DISCUSSION OF PRIOR ART With a section frame of this type known from the German Pat. No. 1.214.375 insulation sections arranged opposite one another are so connected with one another by means of spaced rivets. screws or adhesive bonds that the section lugs of the said insulation sections are maintained in engagement with the section grooves of the frame sections.  
  A disadvantage of the known design consists in the fact that sufficient strength cannot be achieved between the insulation sections by providing fastening rivets or fastening screws at relatively&#39; large distances from one another, and this is particularly disadvantageous if relatively high forces act on the joint between the insulation sections. for instance because of pressure glazing. If. on the other hand, screws or rivets are closely spaced the production of the entire section frame is made more difficult and costly.  
  Although a method known from the German Publication Print 1.659.428 which consists in pressing the section flanges of an insulation section into the appropriate section groove of an inner and outer frame section by means of filler bars produces a firm connection between the frame sections. the process of assembly is relatively difficult and necessitates special devices enabling the fillerbars to be pressed in in such a way as to ensure that they will retain their position after assembly.  
  Finally a method is known from the German Utility Model 1.987350 according to which the thermal insulation between the inner and the outer sides of a window case is achieved by means ofa thermally insulating glazing section in conjunction with a window case seal consisting of thermally insulating material whereas with this known design the problem of the mechanical strength of the connection between an inner frame section and an outer frame section does not in any case arise. it should be noted that the window case of the known window constitutes a thermal short circuit between the inside and the outside so that condensation occurs if there are considerable differences in temperature and humidity.  
 SUMMARY OF THE INVENTION The invention is intended to solve the problem of designing a thermally insulating connection structure between inner and outer frame sections in such a way that using a minimum of individual elements a connection between the frame sections is achieved which is so firm that even relatively high reactions such as may occur in the course of pressure glazing can be safely absorbed even for a prolonged period of time.  
  According to the invention, this problem has been solved with a section frame of the type briefly de scribed above by providing the insulation sections with integrally formed anchoring flanges provided with barbs engaging at the rear of serrated projections which are firmly connected with at least one of the frame sections.  
  The anchoring flange and the serrated projections are in particular so dimensioned and arranged that in the engaged position of the start the insulation sections are elastically deformed in the direction of the movement causing the engagement. The insulation sections are. as a result. pre-stressed in the section grooves of the frame sections. whereby the pre-stress counteracts the forces applied. for instance. by pressure glazing or by a closing mechanism pressing a window casement against the window case. so as to prevent movement due to play.  
  In accordance with an advantageous embodiment two opposite. substantially T-shaped insulation sections are provided. the transverse part of which has short section lugs located parallel to the longitudinal web and engaging the section grooves. whereby the longitudinal web of one of the insulation sections has at its end facing the other insulation section an arrow shaped cross section whereas at the corresponding end of the longitudinal web of the other insulation section is provided with tongue-type barbs encompassing the arrowshaped end of the first insulation section when the two sections are engaged. On the other hand. another embodiment is provided with opposite. substantially T- shaped insulation sections with longitudinal webs having a hook-shaped cross section, which are hooked together in the engaged position.  
 In order to avoid the difficulty that the insulation sec- I tions which are generally made of plastic and preferably produced by extrusion in many cases have an insufficient fatigue strength within the temperature range for which the section frame is intended so that special materials and special manufacturing processes are required. the insulation sections are provided with a longitudinally-arranged metal insert strip. in accordance with an advantageous embodiment.  
  The metal insert strip is in particular provided within the transverse part of the substantially T-shaped insulation sections and equipped with edge flanges which project into the section lugs of the insulationsections.  
  According to a very advantageous characteristic of the section frame of this type the metal insert strip is perforated throughout thus reducing the heat conducting cross section of the metal without any noticeable reduction of mechanical strength.  
  A reduced flexibility and rigidity of the insulation sections owing to the metal insert strips is compensated in an appropriate embodiment of the invention by providing. with a T-shape of the plastic insulation sections. the outer edges with sealing strips consisting of soft plastic which attach tightly against the sections grooves of the frame sections when the section lugs of the insulation sections are pressed into the latter.  
 BRIEF DESCRIPTION OF THE DRAWINGS Certain embodiments are explained below with reference to the drawing.  
  FIG. I shows a part of a section frame in accordance with the invention in cross section.  
  FIGS. Ia and lb are cross-sectional views of a design of the insulation sections which by comparison with FIG. I is modified. at two different stages of assembly.  
  FIG. 2 shows another embodiment of the invention in which the section frames are provided with very wide frame sections.  
  FIG. 3 shows a cross-sectional view of another embodiment of the invention corresponding to FIG. 1.  
  FIG. 3a, shows an embodiment of the invention which has been modified in respect of FIG. 3 and corresponds to the left-hand part of FIG. 2. 4  
  FIG. 4 shows yet another embodiment of the invention than that shown in FIG. 3a.  
  FIG. shows a partial cross section of a window with a section frame in accordance with the invention as shown in FIG. 1 and with a casement frame, thermal insulation of which is achieved by a glazing section which as regards its insulating effect has been designed parallel with the insulation structure of the window case frame,  
  FIG. 6 shows a window of similar type as in FIG. 5 but with fixed glazing,  
  FIG. 7 shows a perspective and partly cross-sectional view of a section frame in accordance with a further embodiment of theinvention. and  
  FIG. 8 shows the detail of the section frame in accordance with FIG. 7.  
 DETAILED DESCRIPTION OF EMBODIMENTS In FIG. I a part of an inner frame section has been designated 1 and a part of an outer frame section 2. The cross section of the frame sections is so designed by provision of hook-shaped section lugs as shown in FIG. 1 or by appropriate shaping of the entire section that each section frame has section grooves 3 and 4 as well as 5 and 6 opening out at right angles&#39;to the plane of the frame.  
  The section lugs 7 and 8 of an insulation section 9 having a substantially T-shaped cross section engage the section grooves 3 and 5, whereas the section lugs 10 and II of section 12, which has also a substantially T-shapcd cross section, engage the section grooves 4 and 6. The insulation sections 9 and 12 each have. by way of longitudinal webs of their T-shaped cross section, an anchoring flange 13 or 14, whereby the outer end of the anchoring flange 13 has an arrow-shaped crossscction whereas the outer end of the anchoring flange 14 is tongue-shaped and is provided with barbs facing inward, the said barbs gripping the outer end of the anchoring flange 13 when the two sections are engaged.  
  In FIG. 1 dash-dotted lines indicate that position of the insulation sections 9 and 12 which these parts would assume in their relaxed state when they are not engaged.  
  During assembly of the frame sections with the insulation sections the cam bered transverse part of each insulation section is so deformed that eventually the anchoring flanges snap in whereafter the deformation of the insulation sections is however maintained and produces a pre-stress capable of restricting the mutual movements of the frame sections 1 and 2.  
  The FIGS. Ia and lb show a cross section of the insulation sections 9 and 12 which is somewhat modified in respect of FIG. 1. The anchoring flange 13 of the insulation section 9 has an arrow-shaped projection 13&#39; extending beyond the barbs of this anchoring flange, whereby the tongue-shaped anchoring flange 14 of the insulation section 12 first cooperates with the said arrow-shaped projection 13&#39; if the two insulation sections 9 and 12 are assembled with relatively little effort without the frame sections being already attached. Disassembly state is shown in FIG. 10. If the insulation sections 9 and 12 are completely compressed after attachment of the frame sections until the barbs of the tongue-shaped anchoring flange l4 engage at the rear of the barbs of anchoring flange 13, the section projection 13&#39; penetrates into a section groove 14 of the anchoring flange 14, the width of which corresponds to the maximum transverse dimension of the section projection 13&#39;.  
  This assembly state is shown in FIG. 1b. The section projection 13&#39; has thus two functions, that of permitting a loose connection of the insulation sections prior to firm assembly of the insulation sections and the frame sections and that of enabling the insulation sections of supporting each other in the state shown in FIG. lb so as to obviate the need of providing an articulated joint in the region of mutual engagement of the anchoring flanges hence the frame sections 1 and 2 can neither lose their alignment nor be displaced parallel to one another even though the entire section system has not yet been assembled to form a frame, inasmuch as individual longitudinal elements of the section system already possess adequate strength for clamping with a view to producing the mitres or corner connecting holes. Of course the design shown in FIGS. 10 and 1b can be applied also to the designs shown in FIGS. 2, 5 and 6, as appropriate.  
  If wide frame sections such as transom sections are to be assembled over an insulating structure in accordance with the invention, the embodiment shown in FIG. 2 may be applied. According to this, insulation sections of the type designated 12 in FIG. 1 are used and again inserted with their section lugs 10 and 11 into section grooves 4 or 6, respectively, and maintained within these section grooves by means of the anchoring flange l4. Contrary to the embodiment shown in FIG. 1, the outer end of the anchoring flange 14 does not, however. grip the corresponding outer end of the anchoring flange of the opposite insulation section but an arrow-shaped section element 15 of a hook-shaped flange produced in one of the frame sections. On the left-hand side of FIG. 2 there is an insulation structure which is symmetrical to the insulation structure that has just been described. With the section frame shown in FIG. 2 the insulation sections 12 can engage the frame sections without any need for the cavity designated 16 in FIG. 2 to be accessible.  
  Whereas with the embodiment in accordance with FIG. 1 differently designed insulation sections 9 and 12 are used, the embodiment according to FIG. 3 is characterised by insulation sections 9a and 9b having identical cross section, whereby the anchoring flanges or 13b, respectively, have a barb-shaped cross section at their outer end so that if the section lugs are pressed into the section grooves of the frame sections thus causing elastic deformation of the insulation sections the barbs are moved into a position in which they engage each other. The barb faces designated l7 are so agled that, on the one hand, excessive deformation of the insulation sections is not required in order to achieve the engagement position, while, on the other hand, the barbs are maintained in the engaged position by the pre-stress of the insulation section, owing to the orientation of the faces 17.  
  FIG. 3a shows that the insulation sections 9a or 9b, respectively, shown in FIG. 3 can also be used in conjunction with a design in which the anchoring flange 13 engages at the rear ofa section element 18 of one of the frame sections whereby the outer end of the section element 18 has a ratchet tooth the face 19 of which is orientated in accordance with the angle of the barb face 17 so that the anchoring flange 13a is again drawn towards the section element 18, owing to the elastic prestressing of the insulation section 9a. once engagement has been brought about. It should be noted that the design shown in FIG. 30 may form part of a section frame with two symmetricallyarranged securing structures approximately as shown in FIG. 2. The same applies also to the insulation design shown in FIG. 4 where however the insulation section 9c is provided with an anchoring flange having a fork-shaped cross section. the fork legs of the said flange being provided with barbs facing in opposite directions. These barbs engage behind engaging projections of opposite section elements 21 and 22 of the frame sections which are to be connected. In all other respects. they function in a similar way as the embodiments described above.  
  FIG. 5 shows a partial section through a window with a window case generally designated 23 and with a casement frame generally designated 24. The window case 23 possesses an insulating structure in accordance with FIG. 1 having the insulation sections 9 and 12 which thermally separate the frame sections 1 and 2 while mechanically connecting them with one another in a very reliable manner.  
  As can be seen in FIG. 5, the frame section 2 is drawn up and rests with its section lug 25 against the glazing section 27 comprising the twin glass panels 26, the said glazing section consisting of synthetic rubber. preferably chlorobutatine.  
  The glazing section 27 is attached to the casement section by means of two anchoring elements 28 and 29, the said casement section being provided with section grooves or slots for the insertion of the anchoring elements 28 and 29. After assembly of the glazing section 27 with the easement section 30 the glass panels 26 are fitted. whereupon the glazing section 27 is sealed over the glass panels by means of a filler bar 31 consisting of the same or similar material.  
  It will be seen that the glazing section 27 substantially located in front of the casement section 30 constitutes a thermal insulation which within the easement frame is parallel to the thermal insulation of the window case. Since there are no other fixing sections. in particular of a metallic nature. which might constitute a thermal bridge to the frame section 2 on that side of the casement frame which faces the letter. It is also significant that the space designated 32 in FIG. 5 and located above the insulation section 12 is protected by a dual seal from moisture when the window is closed. i.e. owing to the section element 25 which firmly attaches to the glazing section 27 and secondly by a sealing lip 33 facing away from the glazing section. whereby the said sealing lip cooperates with a leg 34 of the frame section 1. Any water entering space 32 while the window is open can be drained through apertures in the frame section 2 which are above the insulation section 12 and are not shown in FIG. 5.  
  Entry of water from space 32 into the spaces designated 35 in FIG. 5 is impossible since the section legs of the insulation sections 9 and 12 or 9a, 917 or 90. respectively. are provided with sealing lips and are pressed into the section grooves of the frame sections. The sealing lips are indicated in FIGS. 1, 3, 3a and 4 but are not detailed.  
  FIG. 6 illustrates the application of a section frame in accordance with the invention to fixed glazing systems. In order to enable the twin panels 26 to be located in the same position in respect of the frame section 2 as in the case of casement windows bracket elements 36 engage the frame section 1 in the manner shown in FIG. 6. whereby the said bracket elements36 grip flange 34 of the frame section I by means of a claw-type section element 37, whereas with the embodiment in accordance with FIG. 5 the said flange cooperated with the sealing lip 33. A hook 38 engages a section groove 39 of the frame section 1 with a view to fixing the bracket elements 36.  
  A glazing section 40 which in turn consists of synthetic rubber. preferably chlorobutatine. encompasses the twin panels 26, rests on the bracket elements 36 and bridges the gap between the said bracket elements and the frame section 2 or its section element 25, respectively.  
  The assembly consisting of the twin panels 26 and the glazing section 40 is pressed against the frame section 2 by means of a glazing bar 41 engaging the bracket element 36.  
  Even with fixed glazing in accordance with FIG. 6 the glazing section constitutes an insulation stucture which is parallel to the insulation structure of the window case and at the same time seals the space 32 above the insulation section 12 against moisture. which would reduce the insulating effect of the system.  
 The embodiments in accordance with FIGS. 5 and 6 have this in common. that owing to the reliable connection of the frame sections 1 and 2 by means of the insulation sections it is possible to clamp the glazing section 27 or 40, respectively. between the outer. drawn up section frame and an inner part of the window frame or a casement frame pressed on by means of a closure mechanism. At the same time this insulation structure can be assembled so easily that even at the corners sound sealing of the cavities of the insulation structure can be achieved without difficulty.  
  It should be noted with the embodiments in accordance with FIGS. 5 and 6 that the cross section of the frame comprises at least two chambers filled with static air or free from convection. thus acieving improved insulation capacity as if these chambers were completely filled with an insulating material.  
  The section frame shown in FIG. 7 has two frame sections 1 and 2 which are connected with one another and thermally insulated from one another. these frame sections being only partly and schematically drawn. The frame sections 1 and 2 have section elements with hook-shaped cross sections. which form section grooves 3, 4, 5 and 6 facing away from each other along the respective frame sections. The section lugs 7 and 8 or 10 and 11, respectively. of insulation sections 9 and 12 having sutstantially T-shaped cross sections are inserted in these section grooves as can be seen from FIG. 7.  
  An anchoring flange 13 of the insulation section 9 is provided with a tongue-shaped section which grips a substantially arrow-shaped section element of an anchoring flange 14 of the insulation section 12 if the section flanges 7, 8, l0 and 11 of the insulation sections are pressed into the section grooves of the frame sections 1 and 2 thus causing permanent elastic deformation of the transverse parts of the insulation sections 9 and 12, as described before.  
  A longitudinal metal insert strip consisting of a substantially C -formed aluminium strip 42 which is perforated and about 0.5 mm thick is moulded within the transverse parts of the insulation sections 9 and 12, the said aluminum strip 42 absorbing the mechanical forces acting between the frame sections 1 and 2 and preventing independent expansion of the plastic of insulation sections 9 and 12. Surprisingly enough. the metal insert strip or aluminium insert strip 42 does not increase the heat transfer between the frame sections 1 and 2 to any significant extent. especially because of the perforation. so that the insulating effect of the insulation sections is retained while the mechanical strength is considerably increased.  
  The outer edges of the substantially T-shaped plastic insulation sections 9 and 12 preferably consisting of hard polyvinylchlorides are provided with longitudinal sealing strips 43 consisting of soft polyvinlychloride which attach to the abutting parts of the frame sections 1 and 2 and thus constitute seals. if the section lugs of the insulation sections are pressed into the section grooves of the frame sections.  
 What is claimed is:  
 1. An insulating frame comprising:  
 inner frame means, said inner frame means being provided with a planar side wall portion and at least a first projection extending outwardly therefrom, said first projection having a part extending generally parallel to and spaced from said inner frame means planar side wall portion and cooperating .with said side wall portion to define a first open groove between said projection and said inner frame means side wall portion;  
 outer frame means. said outer frame means being provided with a planar side wall portion and at least a first projection extending inwardly therefrom toward said inner frame means. said outer frame means first projection having a part extending generally parallel to and spaced from said inner frame means planar side wall portion and cooperating with said outer frame means side wall portion to define a second open groove between said projection and said outer frame means side wall portion, said. first and second grooves facing in the same direction, the said first projections of said inner and outer frame means being generally aligned with and spaced apart from one another;  
 insulating means structurally interconnecting said inner and outer frame means. said insulating means including a bridging portion having end flanges extending generally transversely from the opposite ends thereof in a direction opposite to the facing direction of said grooves and engaging said first and second grooves, said insulating means further including an anchoring portion integral with said bridging portion. said anchoring portion extending from said bridging portion intermediate said inner and outer frame means and in a direction generally parallel to said planar side walls of said inner and outer frame means, said anchoring portion being provided with at least a first shoulder adjacent the end thereof disposed away from said bridging portion; and projection means integral with and extending from one of said inner and outer frame means. said projection means having a free end. said projection means engaging said first shoulder of said insulat- 8 ing means anchoring portion and loading said bridging portion in a direction to urge said end flanges into said grooves whereby said insulating means flanges are retained in engagement with said frame means grooves.  
  2. The insulating frame of claim I wherein said end flanges on said bridging portion of said insulating means are provided with serrations which engage the walls of said grooves on said inner and outer frame means.  
  3. The apparatus of claim 1 wherein said inner and outer frame means are each provided with at least a second projection extending from said planar side wall portions in the same direction as said first projections 15 to define longitudinal grooves opening in a direction opposite to that of the grooves defined by said first projections whereby the grooves defined by said second frame means projections may be structurally interconnected by a second of said insulating means.  
 4. The insulating frame of claim 3 further comprising:  
 second projection means extending from one of said sides of said frame means. said second projection means being adapted to engage the anchoring portion first shoulder of a second insulating means to retain the flanges of a second insulating means in engagement with the frame means grooves defined by said second projections.  
  5. The apparatus of claim 1 wherein said insulating frame has an opening for a window section. and further including:  
 a glazing section consisting of thermally-insulating material adjacent said frame opening, at least part of said glazing section abutting on one side directly against said outer frame means.  
 6. The apparatus of claim 5 wherein:  
 said glazing section has integrally formed retaining elements connected to corresponding grooves of a casement frame, said glazing section being clamped between the said casement frame and said outer frame means when the window is closed thus forming a thermal insulation section.  
 7. The apparatus of claim 5 including:  
 bracket means connected to said inner frame section means; and  
 glazing bar means connected to said bracket means;  
 said bracket means supporting a part of said glazing section, said glazing section together with the window being pressed against the outer frame means by said glazing bar.  
 8. The apparatus of claim 1 including:  
 a longitudinal reinforcing strip in said insulating means.  
 9. The apparatus of claim 8 wherein:  
 said reinforcing strip is in said bridging portion of said insulating means and extends with edge flanges into said end flanges of said insulating means.  
 10. The apparatus of claim 8 wherein said reinforcing strip is a perforated metal strip.  
 11. The apparatus of claim 8 wherein:  
 the outer edges of said bridging portion of said insulating means have sealing strips of soft plastic.