WO1988002229A1

WO1988002229A1 - A frame structure

Info

Publication number: WO1988002229A1
Application number: PCT/SE1986/000440
Authority: WO
Inventors: Bo Reinhold Ulfsson Queckfeldt
Original assignee: Q-Bo Mekaniska Aktiebolag
Priority date: 1985-07-08
Filing date: 1986-10-02
Publication date: 1988-04-07
Also published as: SE8503384L; SE8503384D0; SE451175B

Abstract

A frame structure comprising U-shaped frame sections (1-4) each having a front wall (5), a rear wall (6) and a side wall (7) therebetween and being provided with a T-shaped groove (12) consisting of an inner, wider part (13) and an outer, narrower part (14), and said frame structure also comprising junction pieces (22) and locking means (23) to join and hold the frame sections (1-4) together, each junction piece (22) comprising two shanks (24, 25) each having an inner section (26, 27) to be received in said inner part (13) of the groove (12). According to the invention, each shank (24, 25) also comprises an outer section (28, 29) arranged to extend at an angle to the inner section (26, 27) in a space (9) defined by the front, rear and side walls (5, 6, 7) and a transition section (44, 45) between said inner and outer sections (26, 28; 27, 29) arranged to extend through the outer part (14) of the groove (12). Furthermore, each frame section is provided with two slits (20, 21) in the rear wall (6), each slit (20, 21) being arranged at a predetermined distance from an adjacent end joint surface (17 and 18 respectively) so that the outer section (28, 29) of a junction piece (22) inserted in the groove (12) is located within the confines of the slit (20, 21). Said locking means (23) comprise locking fingers (35, 36) for each junction piece (22) to be inserted in said slits (20, 21) to be brought into a position enabling cooperation with the outer sections (28, 29) of the junction piece (22) in order at least to prevent the junction piece (22) being withdrawn from the frame sections (1-4).

Description

A frame structure

The present invention relates to a frame structure comprising a plurality of U-shaped frame sections, the abutting end surfaces of which having acute angles, each frame section having a front wall, a rear wall and a side wall connecting the front and rear walls and being provided internally at its end joint surface with a substantially T-shaped longitudinal groove consisting of an inner, wider part and an outer, narrower part, said groove extend¬ ing at least a predetermined distance from the end joint surface, and said frame structure also comprising angular junction pieces and locking means to join and hold the frame sections together, each of said angular junction pieces comprising two shanks, each having an elongate inner section arranged to be received in said inner part of the groove.

When manufacturing frames for framing various objects, a nail or screw joint is normally used and in many cases even a welded joint in the case of metal frames. It has been time-consuming to make these different types of joints and the welding method has also necessitated finishing the welds by grinding and polishing. Various junction pieces have therefore been suggested for connec¬ ting two frame sections without the use of non-detachable joints such as nails, screws or welds. However, difficulties have then been encountered in obtaining joints which are firmly hold to¬ gether. Furthermore, the frame cannot then be disassembled or is not easily disassembled, which may often be desired to change the object, for instance. The following patents disclose frames hav¬ ing junction pieces of the type described above : SE 7215162-4, GB 2064053, GB 649455, DE 2255378 and DE 2623752. The main object of the present invention is to el iminate the above-mentioned problems and achieve a frame construction entire¬ ly without non-detachable joints of the type mentioned above, which is easy and simple to assemble and disassemble and which can be assembled so that the joints are completely tight in that the end joint surfaces of two frame sections abutting each other.

According to the invention, this object is achieved in that the frame structure has the following main features: that each shank of said junction piece also comprises an outer section arranged to extend at an angle in relation to the inner section in a space defined by the front, rear and side walls of said frame section, and a transition section between said inner and outer sections arranged to extend through the outer, narrower part of the groove; that each frame section is provided with two slits arranged in the rear wall at a predermined distance from and parallel to the side wall, each slit being arranged at a predetermined distance from an adjacent end joint surface, so that the outer section of a junction piece inserted in the groove is located within the confines of the slit; and that said locking means comprise lock¬ ing fingers for each junction piece arranged to be inserted in said slits to be brought into a position enabling cooperation with the outer sections of the junction piece in order at least to prevent the junction piece being withdrawn from the frame sec- tions, whereby said frame structure can be assembled and dis¬ assembled repeatedly without need of tools.

According to a preferred embodiment of the invention said locking fingers are arranged to be brought into engagement with the outer sections of the junction piece and urge these away from the abut¬ ting end joint surfaces, thereby urging the end joint surfaces firmly against each other. The locking means for each junction piece in this case preferably consists of a plate and two locking fingers projecting at right angles therefrom.

The invention will be described further in the following with re¬ ference to the accompanying drawings, in which

Figure 1 shows a picture framing from the rear having a frame structure according to a preferred embodiment of the invention,

Figure 2 is a cross section through the picture framing according to the line II-II in Figure 1,

Figure 3 is an exploded view of a corner of the frame structure,

Figure 4 shows a corner joint while assembling two frame sections and the position of an inner junction piece, indicated by broken lines, and

Figures 5 and 6 show the corner joint in accordance with Figure 4 after application of a locking means for said inner junction piece.

Figure 1 shows a finished picture framing from the rear which has been prepared by means of a frame structure according to a pre¬ ferred embodiment of the invention. The frame structure is compo¬ sed of four straight frame sections 1, 2, 3, 4 having the same cross section. The frame sections are form pressed from a suitable material, preferably aluminium or aluminium alloy and can be easi- ly obtained by cutting a section blank into suitable lengths. Each frame section has a substantially U-shaped cross section and consists of a flangelike front wall 5 of predetermined width, a flangelike rear wall 6, either narrower or of substantially the same width as the front wall 5, and a side wall 7 having prede¬ termined width and rigidly connecting the front wall 5 and rear wall 6 together. The frame section is thus made in one piece with¬ out screw joints or other attachment elements.

The centre plane of the frame is designated 8 (Figure 2). The front wall 5 and rear wall 6 of each frame section is parallel to this plane, whereas the side wall 7 is perpendicular thereto, and thus also to the front wall 5 and rear wall 6.

The inwardly directed front and rear walls 5, 6 of each frame section define between them a longitudinal space 9 (Figure 2), which is open inwardly to receive the edge sections of an object 10 to be mounted in the frame. This object may be composed of different layers or sheets such as a picture, photograph, paint¬ ing or other illustration, passepartout, rear support and front glass. The groove 9 is of predetermined width, suited to the thickness of the object 10 it is to receive, i.e. it is slightly wider than said object so that a gap 11 is formed after framing, between the object 10 and rear wall 6 of each frame section 1-4 (Figure Z) .

Each frame section 1-4 is provided with a longitudinal groove 12 of predetermined size, this groove being on the inside of the front wall 5 and extending without interruption from one end of the frame section to the other, as can be seen in the preferred embodiment shown in the drawings. The groove 12 has generally the form of T or dovetail in cross-section and has an inner part 13 and an outer part 14 which is slightly narrower than the inner part 13, and relatively low. These groove parts 13, 14 are de¬ fined by two flanges 15, 16 facing each other, the distance between the flanges corresponding to the width of the outer part 14 of the groove.

The ends of each frame section are acute-angled to form flat end joint surfaces 17, 18 at an angle of 45° to the side wall 7. Each end joint surface 17, 18 thus lies in a plane at right angles to the centre plane 8. The outer, straight, pointed, edge part thus extends perpendicular to said centre plane 8 and also to the front and rear walls 5, 6.

Furthermore, in the preferred embodiment shown, each frame sec- tion 1-4 is provided with two short slits 20, 21 in the rear wall 6, said slits being in line with each other and parallel to the side wall 7. The slits 20, 21 are through-slits and each is arran¬ ged at a predetermined distance from the side wall 7 so as to be within the area for and aligned with the groove 12 opposite on the inside of the front wall 5. The slits 20, 21 are also arranged at a predetermined and equivalent distance from the end joint surface 17 or 18, respectively.

Said grooves 12 and slits 20, 21, their location and design are important features of the frame structure according to the in¬ vention. Other important features of the invention are that it comprises a specifically shaped corner junction piece 22 and a specifically shaped locking means 23 for each corner junction piece (Figure 3).

As can be seen more clearly in Figure 3, said corner junction piece 22 is shaped as an integral angle plate and comprises two shanks 24, 25 rigidly connected toghether. These shanks have inner sections 26, 27 forming a right angle, and outer, tongue¬ like sections 28, 29 constituting upwardly bent extentions of the sections 26, 27. The outer sections 28, 29 are directed substan¬ tially at right angles to the inner sections 26, 27 and their ex¬ tended planes intersect each other at right angles. The inner sections 26, 27 of the shanks are flat and are located in one and the same plane. Furthermore, each shank 24, 25 has a transition section 44, 45 extending between the outer and inner sections 26, 28 and 27, 29, respectively. The transition sections 44, 45 are suitably curved in order to achieve better spring action when the shank is of a spring material, which is preferred. The transition sections 44, 45 are thus narrower than the inner sections 26, 27 of the shanks and slightly narrower than the width of the outer part 14 of the groove 12, in order not to prevent insertion of the shanks 24, 25 into the groove. The inner sections 26, 27 and transition sections 44, 45 of the corner junction piece are thus intended to be received in the grooves 12, and the outer sections 28, 29 in the spaces 9 of two adjacent frame sections, e.g. 1 and 2, located at right angles to each other. The width of the inner section 26, 27 of a shank 24, 25 and the width of the inner part 13 of the groove 12 are thus adapted to each other to enable the shank to slide into the groove 12 without obstruction, i.e. a small clearance exists between opposing surfaces, but not so great as to cause instability in the frame structure. The portion 30 of the inner section 26, 27 nearest to the transition section 44, 45 is suitably somewhat narrower, e.g. the same width as the transition section, as shown in Figure 3, and partially wedge- shaped. Insertion of the shank into the groove 12 is thereby fa- cilitated. The length of each shank 24, 25 and the distance of the slit 20, 21 to the end joint surface 17, 18 are adapted to each other so that the outer section 28, 29 of the shank is located within the area of and in line with the slit 20, 21 and so that this outer section 28, 29 is thus inside and at a predetermined distance from the outer edge 31 located nearest the end joint surface 17, 18.

To achieve fast and immediate alignment of two opposite end joint surfaces 17, 18 of two frame sections 1, 2 which are to form a corner, it is advantageous to limit the extent to which the shanks 24, 25 can be inserted. With a continuous groove 12 this is achieved in that the inner edge 32 (Figure 3) of the groove 12 is located in the plane of the end joint surface 17, 18 to pro- vide a stop for the other shank when the first shank is inserted in the groove 12.

Said locking means 23 for each corner junction piece may consist of two separate clamps (not shown) of spring material, each hav- ing a finger which is inserted in to the slit 20, 21 and will therefore be pressed both against the upwardly directed outer section 28, 29 of the shank 24, 25 and against the outer edge 31 of the slit 20, 21, which thus serves as a support so that the outer section 28, 29 and thus the shank 24, 25 is urged away from the end joint surface 17, 18, respectively. If, therefore, both shanks 24, 25 are inserted in the grooves of their respective frame sections, the end joint surfaces 17, 18 will be drawn to¬ wards each other to give a tight and firm joint. Such a clamp has a snap lock which cooperates with the free edge of the rear wall of the frame section so that the clamp is retained in its locking position. Figure 4 shows a locking means 23 which is preferred over the em¬ bodiment described above. It consists of an integral unit having a flat plate 34 and two rigid locking fingers 35, 36 extending therefrom at right angles. The extended planes of the locking fingers 35, 36 intersect each other at right angles and they are spaced from each other to enable simultaneous insertion into the slits 20, 21 of two frame sections 1, 2 set at an angle to each other, thus engaging with the upwardly directed outer sections 28, 29 of the corner junction piece so that each outer section 28, 29 and the entire shank 24, 25 are urged away from the end joint surfaces 17, 19 abutting each other. It will be understood that in this case it is not the position of the outer edge 31 of the slits 20, 21 which is critical, at least not with respect to achieving the pressure forces acting upon the outer sections 28, 29 of the shanks 24, 25. However, each slit 20, 21 must be suffi¬ ciently long to allow the locking fingers 35, 36 of the plate to be inserted through them to achieve the desired cooperation with the outer sections 28, 29 of the corner junction pieces. The ope¬ rative side surfaces 46, 47 (Figure 3) of the locking fingers 35, 36 of the plate 33 are inclined in that the free ends of the locking fingers are bevelled to wedge shape. Since the corner junction piece consists of a spring material, e.g. tempered sheet iron, these outer sections 28, 29 will yield resiliently to pressure from the locking fingers 35, 36 on the plate 33, thus gradually producing a pressure while at the same time exerting a locking effect on the plate 33 itself so that this is retained in its operative position in contact with the rear wall 6 of the frame section and hidden in a recess 37 therein. However, it is preferred that the distance between the outer edge 31 of the slit 20, 21 and the outer section 28, 29 of a corner junction piece is somewhat less than the width of the locking finger 35, 36 so that this outer edge 31 serves as support for the locking finger 35,36 while the outer section 28, 29 is resiliently bent away by the locking finger.

As will be seen in Figures 1 and 2, the frame structure according to the invention also includes two specially shaped holders 38 each having a part which is generally U-shaped having a first shank 39 extended to a tongue 40 projecting freely from the frame section 2 and having an aperture 41 for attachment of a wire or the like, to enable suspension of the frame. The first shank 39 extends along the inside of the rear wall 6 of the frame section while the other shank 42 is received and slides along in the groove 12 on the inside of the front wall 5 of the frame section. The length of the second shank 42 is limited to slightly less than the width of the inner part 13 of the groove 12 to allow movement of the holder 38 along the groove 12 without it becoming wedged or caught in some other way. Similarly there is some clearance between the first shank 39 and the inside of the rear wall 6 for the same reason. The holder 38 is thus arranged per¬ pendicular to the frame sections 2, 4, and is displaceable in the groove 12 and space 9 in the longitudinal direction of the frame section, enabling it to be set in the desired position along the frame section. The holder has a suitable width, e.g. 5-20 mm, depending on the dimensions of the frame section.

The frame structure according to the invention also includes a special clamping means 43 to position both the object 10 to be framed and the holders 38. According to the preferred embodiment shown, the clamping means consists of a flexible hose 43 of pre¬ determined length, compressible in transverse direction for com- press ion in the space 9 between rear wall 6 and front wall 5 thus pressing the framed object against the inside of the front wall 5 and at the same time clamping the holders 38 in the positions set, the hose 43 pressing them towards the inside of the rear wall 6. The hose can thus easily be released. The hose should preferably be long enough to reach around the entire frame, at least one end, e.g. the end 48, being allowed to protrude from the space 9 of the frame section 1 in order to be easily accessible when the frame is to be disassembled to exchange the object, adjust it or merely adjust the positions of the holders 38 which can then be moved freely without being obstructed by the framed object 10. The other end of the hose is preferably inserted into the space 9 and completely hidden there. Although a hose is preferred as clamping means, since the hollow space facilitates compression to an oval shape (see Figure 2), a solid strip of flexible material may be used which can be correspondingly compressed. The clamping means generally possesses sufficient friction to ensure that it cannot slip out of position. Another extremely important function of the clamping means 43 is to seal the framed object 10 so that dust, moisture, etc will be prevented from penetrating into the spaces 9 and thus keeping the picture, photograph, painting or other illustration intact.

The frame structure according to the invention can also be used for other types of objects to be framed, such as mirrors, panels of various types such as decorative panes of glass, etc.

A frame structure is thus obtained which can be easily and simply assembled and disassembled repeatedly, without requiring special tools, the finished frame having completely tight joints and be¬ ing as firm as a nailed, screwed or wel ded joint.

Claims

___________L

1. A frame structure comprising a plurality of substantially U-shaped frame sections (1, 2, 3, 4), the abutting end surfaces (17, 18) of which having acute angles, each frame section having a front wall (5), a rear wall (6) and a side wall (7) connecting the front and rear walls and being provided internally at its end joint surface (17, 18) with a substantially T-shaped longitudinal groove (12) consisting of an inner, wider part (13) and an outer, narrower part (14), said groove extending at least a predetermined distance from the end joint surface (17, 18), and said frame structure also comprising angular junction pieces (22) and lock¬ ing means (23) to join and hold the frame sections (1, 2, 3, 4) together, each of said angular junction pieces (22) comprising two shanks (24, 25), each having an elongate inner section (26, 27) arranged to be received in said inner part (13) of the groove (12), characterized in that each shank (24, 25) of said junction piece (22) also comprises an outer section (28, 29) arranged to extend at an angle in relation to the inner section (26, 27) in a space (9) defined by the front, rear and side walls (5, 6, 7) of said frame section, and a transition section (44, 45) between said inner and outer sections (26, 28; 27, 29) arranged to extend through the outer, narrower part (14) of the groove (12); that each frame section is provided with two slits (20, 21) arranged in the rear wall (6) at a predermined distance from and parallel to the side wall (7), each slit (20, 21) being arranged at a pre- determined distance from an adjacent end joint surface (17 and 18, respectively) so that, the outer section (28, 29) of a junction piece (22) inserted in the groove (12) is located within the confines of the slit (20, 21); and that said locking means (23) comprise locking fingers (35, 36) for each junction piece (22) arranged to be inserted in said slits (20, 21) to be brought into a position enabling cooperation with the outer sections (28, 29) of the junction piece (22) in order at least to prevent the junc- tion piece (22) being withdrawn from the frame sections (1-4), whereby said frame structure can be assembled and disassembled repeatedly without need of tools.

2. A frame structure according to claim 1, characterized in that said locking fingers (35, 36) are arranged to be brought into engagement with the outer sections (28, 29) of the junction piece (22) and urge these away from the abutting end joint surfaces (17, 18), thereby urging the end joint surfaces firmly against each other.

3. A frame structure according to claim 1 or 2, characteri¬ zed in that said locking means for each junction piece consists of a plate (33) and two locking fingers (35, 36) projecting at right angles therefrom.

4. A frame structure according to claim 3, characterized in that the distance between the edge (31) of the slit (20, 21) nearest the end joint surface (17, 18) and the outer section (28, 29) of a junction piece (22) inserted in the groove (12) is some¬ what less than the width of the locking finger (35, 36) so that this outer edge (31) serves as support for the locking finger (35, 36) while it is bending away the outer section (28, 29).

5. A frame structure according to any of the preceding claims, characterized in that the groove (12) at one end joint surface (17) of the frame section extends to the other end joint surface (18) of the frame section, thus forming a through-running groove.

6. A frame structure according to any of cl aims 2 to 5, characterized in that said transition section (44, 45) of each shank (24, 25) has a curved form with a predetermined radius and in that the junction piece (22) consists of a spring material so that said locking fingers (35, 36), which are relatively stiff, are arranged to urge aside the outer sections (28, 29), which are thus resilient, while producing a clamping tension in the junc- tion piece.

7. A frame structure according to any of the preceeding claims, characterized in that the lateral surface of each locking finger (35, 36) cooperating with the outer section is bevelled in order gradually to urge aside the outer section (28, 29) in a direction away from the end joint surface (17, 18) when the locking finger is inserted through the slit (20, 21).

8. A frame structure according to any of the preceeding claims, characterized in that it also includes holders (38) for suspending the frame together with the framed object (10), said holders (38) having a part which is generally U-shaped having a first shank (39) extended to a tongue (40) projecting freely in¬ wards from the frame section and having an attachment (41) for attachment of a wire or the like, and a secon shank (42) arrangedd to be received and to slide into said groove (12), said holders being arranged in two parallel frame sections (2, 4), at right angles thereto and displaceable in the groove (12) and space (9) in a frame section enabling them to be adjusted and locked in the desired position.

9. A frame structure according to any of the preceeding claims, characterized in that it also includes a clamping means (43) to position both the object to be framed (10) and the holder onto the frame sections, said clamping means consisting of a hose, band or the like of an elastic material arranged while in com¬ pressed state to be inserted into the space (9) in order to urge the framed object (10) against the inside of the front wall (5) and at the same time clamp the holders (38) in the positions set, the clamping means pressing them towards the inside of the rear wall (6).

10. A frame structure according to claim 8, characterized in that the length of the clamping means (43) corresponds substan¬ tially to the circumference of the frame.

11. A frame structure according to claim 10, characterized in that the clamping means (43) is arranged to seal the framed ob¬ ject (10) and its edges against dust, moisture and the like.