US3645058A

US3645058A - Mullion device for window

Info

Publication number: US3645058A
Application number: US805164A
Authority: US
Inventors: Allan I Jacobson; Philip J M Fisher
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-03-07
Filing date: 1969-03-07
Publication date: 1972-02-29
Anticipated expiration: 1989-02-28

Abstract

A removable mullion device or grill, for use with a single-light window to simulatively convert same to multiple light, fabricated of hollowed-out mullion tubes which can be joined together to make selectively variable patterns and sizes utilizing crossjoint connectors for the intersecting angular joints of the mullion tubes, utilizing inserting members for fastening the mullion tubes at the corners of the sash and with the cross-joint connectors, angle-joint connectors and inserting members being received and carried interiorly of the mullion tubes. Also discloses two methods of heat bonding to structurally bond and unite the connectors with the plastic mullion tubes to make permanent cross joints and angle joints. Also discloses bevel cutting of the mullion tubes for cam or wedge locking of the mullion tubes with the window sash. Also discloses an adaptation of the cross-joint connectors for use with runners of a suspension grid for ceilings to form a variety of diamond-shaped patterns. Also discloses an adaptation of the cross-joint connectors, and the use of a cross-joint connector with a T-joint connector, for geodesic structure.

Description

Q United States Patent [151 3,645,058

Jacobson et al. 1 Feb. 29, 1972 [54] MULLION DEVICE FOR WINDOW 3,372,522 3/1968 Engstrom ..52/507 X 721 Inventors: Allan I. Jacobson, 48-6 Woodlake Rd, gggfigi 232: fgggf "3528; f Albany 12203; Philip 3 386 219 6/l968 Beil.........::::: :52/507 x Fisher, 81 Fairfield Ave, Albany, NY. 421-205.

Primary Examiner-Alfred C. Perham [22] Filed: Mar. 7, 1969 Attorney-Walter F. Wessendorf, Jr.

[21] Appl. No; 805,164 [57] ABSTRACT l, A removable mullion device or for use with a singleJighl 52/5 5 28 -3 A window to simulatively convert same to multiple light, [51] Int- Cl- 04 /5 fabricated of hollowed-out mullion tubes which can be joined [58] Field of Search ..52/31 1, 309, 484, 507, 456, together to make selectively variable patterns and sizes utiliz- 52/648, 656, 658, 663, 665; 287/1 89.36 A, 20.92 E; ing cross-joint connectors for the intersecting angular joints of 46/26, 29 the mullion tubes, utilizing inserting members for fastening the mullion tubes at the comers of the sash and with the cross- [56] References Cited joint connectors, angle-joint connectors and inserting members being received and carried interiorly of the mullion tubes. N TED TATE PATENTS Also discloses two methods of heat bonding to structurally 1,912,920 6/1933 Saunders ..52/4s4 with "F 2 063 895 12/1936 M to make permanent cross olnts and angle oints. Also dlsack ..46/29 X 3 358 412 l2/l967 52/3 closes bevel cutting of the rnulllon tubes for cam or wedge 3'004784 10/1961 S lb 92 locking of the mullion tubes with the window sash. Also dis- 08336 0 963 e y closes an adaptation of the cross-joint connectors for use with 1 l1 Tate "52/311 runners of a suspension grid for ceilings to form a variety of 3J4} 7/1964 P 52/406 X diamond-shaped patterns. Also discloses an adaptation of the 330358] 2,1967 Levmson'" x cross-joint connectors, and the use of a cross-joint connector K 'f with a T-joint connector, for geodesic structure. neger..... 3,355,206 i 1/1 967 Valsvik ..52/665 X 36 Claims, 20 Drawing Figures Patented Feb. 29, 1972 4 Sheets-Sheet 1 FIG.|.

Patented Feb. 29, 1972 3,645,058

4 Sheets-Sheet 5 F|G.l6.

INVENTORS ALLAN I- JACOBSON PHILIP J.M.F|SHER Patented Feb. 29, 1972 4 ts-Sheet 4.

INVENTORS ALLAN I. JACOBSON MULLION DEVICE FOR WINDOW This invention relates to a removable mullion device or grill for use with a single-light window to simulatively convert same to multiple light.

In multiple-light windows and single-light windows converted to give the appearance of multiple lights, the lights are either of square or rectangular shape, or are of diamond or triangular shape. With respect to the former, the mullion bars intersect normal to each other. With respect to the latter, the mullion bars intersect at an angle to each other. With respect to the intersecting mullion bars of both, the mullion bars are mitered and then coped to effectuate complemental fit at the cross joints. This necessary mitering and concomitant coping of the mullion bars to achieve complemental fit by and of itself presents a manufacturing problem, involves a high degree of quality control and results in materials waste, and thereby increases the manufacturing costs of the mullion devices. These described factors which materially contribute to increased manufacturing costs are especially prevalent in the manufacturing of mullion bars for the diamond-shaped lights. One of the objects of this invention, therefore, is to contribute to the solution of this discussed problem of the art by providing mullion bars to form the cross joints, and which mullion bars when utilized with the cross-joint connectors of the invention need only be mitered at 90 degree angles but are not required to be coped.

Another problem in this art is the cross joint itself and the means by. which the intersecting mullion bars are joined together at their cross joints. Conventionally, the intersecting mullion bars at their cross joints are joined together either by gluing them together, by inserting a pin through a hole formed in a mullion bar and then attaching the pin to the other mullion bars by means of specially formed adapter or grommets carried by these other mullion bars, or by combinations of these two described means. The conventional means by which the intersecting mullion bars are joined together at their cross joints likewise is a problem in this art and materially contributes to increased manufacturing costs of the mullion devices. Another object of this invention, therefore, is to contribute to the solution of this additional problem of the art by providing and utilizing simple, inexpensive but durable, universal cross-joint connectors which are inserted interiorly of the mullion tubes or bars, and which structurally cooperate with the mullion tubes to join together the mullion tubes normal to each other or at optional angles to each other depending upon the particular pattern of the diamond-shaped lights.

Another problem in this art is encountered especially in fastening a mullion tube to the sash comer when the pattern is that of diamond-shaped or triangle-shaped lights. Conventionally, the mullion tube is mitered and then fastened in such comer by an inserting member or fastening member carried by the mullion tube and then engaging the fastening member with a corner plate or other element mounted in the corner of the sash to thereby fasten the mullion tube to the comer of the sash. This problem not only increases the materials costs of manufacturing the mullion device, but also adds to the amount of time required to mount the mullion device on the window sash. A further object of this invention is to contribute to the 60 joint connector;

solution of this discussed problem in the art by providing a universal-type inserting member which is received interiorly of the mullion tube and carried thereby, and which is utilized to fasten the mullion tube to the corner of the sash. Another important and unique structural feature of this universal-type inserting member is the fact, that the mullion tube with respect to its longitudinal axis can be mounted at an angle ranging from 28 to 62 relative to the' stiles or rails with respect to their axes.

Another problem in the art is encountered in the angular joints formed by the mullion tubes which intersect angularly at. the lateral sides of the mullion device for the pattern of diamond-shaped lights. Conventionally, the intersecting-mullion tubes are mitered, grommets are insertedwithinthe mul-s then the pin is bent to the required angle to dispose the intersecting mullion tubes at the correct angle for the angular joint. This problem not only increases the materials cost of manufacturing the mullion device, but also adds to the amount of time required to construct the angular joints of the intersecting mullion tubes. A still further object of this invention is to contribute to the solution of this discussed problem in the art by providing and utilizing a connector whose ends are simply inserted interiorly of the intersecting mullion tubes after same have been mitered, and then simply bending the connector to the required angle of the angular joint.

The cross-joint and angle-joint connectors of the invention are removable from the mullion tubes and can be reinserted in the mullion tubes.

The cross-joint and angle-joint connectors inserted in the mullion tubes can be permanently bonded to their mullion tubes by a modification of the invention which involves providing the ends of the connector with a surface roughness and by utilizing two methods of heat-bonding the connectors to their mullion tubes to structurally bond and unite the connector ends with the mullion tubes.

A significant structural feature of the invention is the bevel cutting of the mullion tubes to provide thereby cam or wedge locking of the mullion tubes with respect to the sash and thereby eliminate the need for the inserting members for fastening the mullion tubes at the comer joints of the sash. This cam or wedge locking can be provided at either the angular joints and/or at the corner joints of the mullion tubes. The dimensional measurement of the required length of the mullion tubes is governed by the width and height of the visible glass surface area. The bevel cut passes through the center of the mullion tubes in order that the downward or bottom portions of the mullion tubes facing the surface of the single-light window are dimensionally undercut and the upper portions of the mullion tubes are dimensionally overcut. Hence their center portions of their center bevel cuts will correspond to the required lengths dimensionally of the mullion tubes, by width and height, to fit the visible glass surface area.

A significant adaptation of the invention is the use of the cross-joint connectors with runners of suspension grids for ceilings to form a variety of diamond-shaped patterns.

A further significant adaptation of the invention is the use of the cross-joint connectors, and the use of a cross-joint connector with a T-joint connector for each T-joint, for geodesic structures.

These objects and other objects of the invention should be discerned and appreciated from the detailed specification taken in conjunction with the drawings, wherein like reference numerals refer to similar parts throughout the several views, in which:

FIG. 1 is a view of a diamond-shaped mullion device,

FIG. 2 is a view, partly in section, of a cross joint formed by the intersecting mullion tubes joined together by the crossjoint connector;

FIG. 3 is a view of a cross-joint connector;

FIG. 4 is a view, partly in section, of an angular joint formed by intersecting mullion tubes and joined together by an angle- FIG. 5 is a view of an angle-joint connector;

FIG. 6 is a sectional view, taken in the direction of the arrows 66 in FIG. 1, and shows the inserting member, received and carried interiorly of a mullion tube, utilized to fasten the mullion tube to the comer of the sash;

FIG. 7 is a view of the inserting member;

FIG. 8 is a view of the inserting member taken in the direction of the arrow 8 in FIG. 7

FIG. 9 is a view, in perspective, of the inserting member;

FIG. 10 is a view, partly in section, taken in the direction of the arrow 10 in FIG. 4, of the angular joint and further shows the bevel cut of the mullion tube for cam or wedge locking of the mullion device with respect to the window sash;

FIG 11 is a partialview of the angle-joint connector and lion tubes, both ends of a pin are inserted in the grommets and shows the rough surface of one of its end portions;

FIG. 12 is a sectional view of a mullion tube taken in the direction of the arrows 12--12 in FIG. 1;

FIG. 13 is a view of a suspension grid for a ceiling in a diamond-shaped pattern;

FIG. 14 is a view of a cross joint formed by intersecting runners joined together by cross-joint connectors;

FIG. 15 is a sectional view taken in the direction of the arrows 15-15 in FIG. 14;

FIG. 16 is a view taken in the direction of the arrow 16 in FIG. 14;

FIG. 17 is a view of a geodesic structure;

FIG. 18 is a view taken in the direction of the arrow 18 in FIG. 17 and shows an assembled T-joint;

FIG. 19 is a view, in perspective, of a T-joint connector and a cross-joint connector;

FIG. 20 is a view, partly in section, taken in the direction of the arrows 20-20 in FIG. 18.

To facilitate the understanding in conjunction with the drawings, a nomenclature list is herewith provided.

1 mullion device or grill 3 mullion tube 5 mullion tube 7 mullion tube 9 mullion tube 11 mullion tube 13 mullion tube 15 mullion tube 17 mullion tube 19 flat upper surface 21 flat lower surface 23 flat top surface 25 flat bottom surface 27 inclined web 29 inclined web 31 inclined web 33 inclined web 35 stile 37 stile 39 rail 41 rail 43 window 45 single light 47 cross joint 49 cross joint 51 angular joint 53 angular joint 55 corner joint 57 comer joint 59 comer joint 61 comer joint 63 inserting member 65 inserting member 67 inserting member 69 inserting member 71 cross-joint connector 73 raised, shoulder portion 75 remaining portion 77 end 79 end 81 radius 83 radius 85 radius 87 radius 89 angle-joint connector 91 end 93 end 95 reduced center portion 97 plane 99 projecting point 101 neck 103 serrated flange 105 main body portion 107 transverse wing portion 109 transverse wing portion l 11 piercing point 113 lateral edge 115 lateral edge 117 lateral side 119 lateral side 121 longitudinal slot 123 right edge 125 left edge 127 bevel cut 129 overcut upper portion 131 undercut lower portion 133 rough surface 135 generally refers to diamond-shaped suspension grid I37 cross-joint connector 139 runner 141 vertical web 143 tubular ridge 145 flange 147 flange 149 wire 151 ceiling panel 153 generally refers to geodesic structure 155 cross joint 157 cross joint 159 cross joint 161 cross joint 163 cross joint 165 crossjoint 167 cross joint 169 T-joint 171 T-joint 173 T-joint 175 mullion tube 177 mullion tube 179 mullion tube 181 cross-joint connector 183 T-joint connector 185 remaining portion 187 end 189 end 191 remaining portion 193 end 195 end 197 tenninal hook portion other.

In FIG. 1 of the drawings, reference numeral 1 generally refers to the mullion device or grill of diamond-shaped and triangle-shaped pattern mounted and fastened to the window sash. The mullion device or grill 1 comprises the mullion bars or

tubes

3, 5, 7, 9, 11, 13,15 and 17.

The mullion tubes, each of which is of integral, one-piece construction, are extruded of medium rigid polyvinyl chloride plastic to maintain their uniform shapes. Each mullion tube has relatively flat upper and

lower surfaces

19 and 21 symmetrically disposed with respect to each other and relatively flat top and

bottom surfaces

23 and 25 symmetrically disposed with respect to each other.

Inclined webs

27, 29, 31 and 33 joint the

surfaces

19 and 23, 23 and 21, 21 and 25, and 25 and 19, respectively. The interior surfaces of

webs

27, 29, 31 and 33 are substantially parallel to their respective outer surfaces; and the interior surfaces of 19, 21, 23 and 25 are substantially parallel to their respective outer surfaces. These described details are shown in FIG. 12.

The mullion device 1 is shown mounted in FIG. 1 with respect to the

stiles

35 and 37, and rails 39 and 41, of window 43, and with respect to the single light 45. The intersecting mullion tubes 3, 5, 7 and 9, and the intersecting

mullion tubes

11, 13, 15 and 17, are joined together in removable cross joints 47 and 49, respectively. The intersecting mullion tubes 7 and 11, and the intersecting mullion tubes 9 and 13, are joined together in removable

angular joints

51 and 53, respectively. Four corner joints 55, 57, 59 and 61 are formed by the stile 35 and rail 39, rail 39 and stile 37, stile 37 and rail 41, and rail 41 and stile 35, respectively. The

mullion tubes

3, 5, 17 and 15 are fastened to the comer joints 55, 57, 59 and 61,

respectively, by respective inserting

members

63, 65, 67 and 69.

Cross joint 47 is shown in greater detail in FIG. 2. The cross joint 47 is made of the four mullion tubes 3, 5, 7 and 9 whose ends have been mitered by 90 degree cuts only, without coping, and structurally joined together by two cross-joint con nectors 71. A cross-joint connector 71 is shown in greater detail in FIG. 3. Connector 71 is preferably made of aluminum and is of right circular cylindrical configuration having a raised, shoulder portion 73 in the middle which functions as a limit stop, having a half-cylindrical portion removed from the middle thereby leaving a remaining portion or recess 75, and having two ends 77 and 79. As shown in FIGS. 2 and 3, the remaining portion or recess 75 is defined by a bottom wall and two end walls. The width of the bottom wall is the same as the diameter of connector 71. The length of the bottom wall is greater than its width. The cross-sectional view of the mullion tube in FIG. 12 is bisected by construction (not shown) and has four

equidistant radii

81, 83, 85 and 87 radiating from the center to the interior surfaces of the

inclined webs

27, 29, 31 and 33. The radial distances enumerated by reference numerals are the shortest radial distances from the center of the bisected section to the interior surfaces of these inclined webs.

Radii

81, 83, 85 and 87 are less than the co-equal radii of the ends 77 and 79 of cross-joint connector 71. Accordingly, retentive interference fit is provided by those portions of the interior surfaces of the

inclined webs

27, 29, 31 and 33 whose

respective radii

81, 83, 85 and 87 are dimensionally less than the radius of each of the ends 77 and 79 of cross-joint connector 71 when an end of cross-joint connector 71 is inserted interiorly of a mullion tube. The radius of the raised, shoulder portion 73 is slightly greater dimensionally than the radii of ends 77 and 79 such that slightly greater interference fit results upon initial engagement of shoulder portion 73 with the interior of the mullion tube.

As the shoulder portion 73 is further inserted interiorly of the mullion tube, the interference fit increases to a point of engagement whereat and whereby shoulder portion 73 functions as a limit stop to prevent further interior insertion. Shoulder portion 73 is arranged and constructed to admit of sufficient interior insertion to allow the mullion tubes to be disposed in abutting relationship and such point of limit-stop engagement is where the mullion tubes are thusly disposed in such abutting relationship. When an end of cross-joint connector 71 is inserted interiorly of a mullion tube in a direction of coincidence of the longitudinal axes of the cross-joint connector 71 and the mullion tube, such cross-joint connector end can only be inserted interiorly of the mullion tube to such point of limit-stop engagement of the shoulder portion 73 with the interior of the mullion tube.

Cross joint 47 is assembled, and other cross joints would similarly be assembled, by partially inserting the ends of a crossjoint connector 71 interiorly of the mitered ends of mullion tubes 5 and 7, and then the ends of the other cross-joint connectors are partially inserted interiorly of the mitered ends of mullion tubes 3 and 9. The cross-joint connectors 71 are disposed relative to each other such that their respective bottom walls are in abutting relationship similar to a blind-halved lap joint, and then the mullion tubes 3, 5, 7 and 9 are pushed together sufficiently such that their mitered ends are in abutting relationship with one another as shown in FIG. 2. This described assembly results in a structural cross joint. The mullion tubes 3, 5, 7 and 9 forming cross joint 47 can be disassembled by simply extending mullion tubes 3 and 9 outwardly, and extending mullion tubes 5 and 7 outwardly, sufficiently to disengage these mullion tubes from the ends of their crossjoint connectors 71. l

In the assembly of the cross-joint connectors 71, their longitudinal axes constitute intersecting straight lines denoted as intersecting straight lines for purposes of the explanation to be afforded herein and form thereby two pairs of vertical angles whose nonadjacent angles are equal and each of whose adjacent angles are supplementary. As viewed in FIG. 2, mullion tubes 3 and 7 form an acute angle equal to its nonadjacent angle formed by mullion tubes 5 and 9, and mullion tubes 3 and 5 form an obtuse angle equal to its nonadjacent angle formed by mullion tubes 7 and 9. As may be expressed more clearly and briefly, mullion tubes 3 and 7, and 5 and 9, form acute vertical angles that are equal; and mullion tubes 3 and 5, and 7 and 9, form obtuse vertical angles that are equal. Therefore, it should be appreciated that, on the one hand, engagement of the end walls of one cross-joint connector with the other cross-joint connector, and vice versa, detennine and limit the smallest acute angle formed by each of the mullion tubes 3 and 7, and 5 and 9, and the greatest obtuse angle formed by each of the mullion tubes 3 and 5, and 7 and 9; and, on the other hand, with such described type of assembly of the connectors 71 assumed, that increase in the length of the bottom walls ofthe connectors 71 will correspondingly decrease the angle of the acute angle fonned by 'eachof the mullion tubes 3 and 7, and 5 and 9, and correspondingly increase the angle of the obtuse angle fonned by each of the mullion tubes 3 and 5, and.7 and 9. It should further be appreciated that relative movement of the connectors 71 permits the one pair of vertical angles to vary and range from acute to obtuse and the other pair of vertical angles to correspondingly vary and range from obtuse to acute.

It should also be appreciated that the described structure of the crossjoint connectors 71 and the description of how the mullion tubes 3, 5, 7 and 9 and cross-joint connectors 71 are assembled to form structural cross joint 47 would apply similarly to the assembly of structural cross joint 49 and other cross joints. It should further be appreciated that the mullion tubes and cross-joint connectors 71 can be utilized to form structural cross joints for colonial patterns wherein the lights are square-shaped or rectangular-shaped, and that the cross-. joint connectors 71 can be utilized with the mullion tubes to form a variety of cross joints with the mullion tubes intersecting at a variety of angles.

Angular joint 51 is shown in greater detail in FIG. 4. The angular joint 51 is made of the two mullion tubes 7 and 11 whose ends have been mitered by cuts only, without coping, and structurally joined together by the angle-joint connector 89. An angle-joint connector 89 is shown in greater detail in FIG. 5. Connector 89 is preferably made of aluminum and is of right circular cylindrical configuration having two ends 91 and 93 of equal radii separated by a reduced center portion whose radius is less than the radii of

ends

91 and 93. The ends 91 and 93 of the angle-joint connector 89 have the same radii as those of the ends 77 and 79 of the cross-joint connector 71. Hence, retentive interference fit is provided by those portions of the interior surfaces of the

inclined webs

27, 29, 31 and 33 of the mullion tubes whose

respective radii

81, 83, 85 and 87 are dimensionally less than the radius of each of the

ends

91 and 93 of the angle-joint connector 89 when an end of anglejoint connector 89 is inserted interiorly of a mullion tube. Angular joint 51 is assembled, and other angular joints would similarly be assembled, by inserting the ends of the angle-j oint connector 89 interiorly of the ends of the mitered mullion tubes 7 and 11 sufficiently such that the common mitered ends of mullion tubes 7 and 11 are in abutting relationship when the reduced center portion 95 is bent to conform to the required angle ofv the angular joint 51 and such that no portion of the thusly, angularly bent, reduced center portion 95 will protrude beyond the plane 97 formed by the aligned mitered ends of the mullion tubes 7 and 11. This described assembly results in a structural angular joint. The mullion tubes 7 and 11 forming angular joint 51 can be disassembled by simply extending mullion tubes 7 and 11 outwardly sufficiently to disengage these mitered ends of the mullion tubes from the ends of their anglejoint connector 89.

FIG. 6 of the drawings shows the end of mullion tube 3 fastened to the corner joint 55 by means of the inserting member 63. The inserting members are made of a high impact thermoplastic of thestyrene classof plastics and are formed by injection molding. lnaddition to FIG. 6 of the drawings,

further details of an inserting member are shown in FIGS. 7, 8 and 9. Except for its projecting point 99, the inserting member is of integral, one-piece construction and has a neck 101, serrated flange 103, main body portion 105 and two symmetrical,

transverse wing portions

107 and 109 extending oppositely outwardly from the main body portion 105. The projecting point 99 is centrally imbedded in one end of the main body portion 105 and is made of stiff wire of high carbon steel whose piercing point 11 l is ground. The lateral edges 1 13 and 115 of the respective

transverse wing portions

107 and 109 are rounded, as shown. The symmetrical,

lateral sides

117 and 119 of respective

transverse wing portions

107 and 109 are formed at the angle, as shown. If coincidental, imaginary lines coplanar with the planes of

lateral sides

117 and 119 were extended to meet and form the apex of a triangle, the included angle would be 56 degrees. A longitudinal slot 121 is formed through the flat upper surface 19 of the mullion tube 3. The width of longitudinal slot 121 is dimensionally less than the width of neck 101 to provide thereby interference fit when inserting member 63 is inserted interiorly of mullion tube 3. The rounded lateral edges 1 13 and 115 of

transverse wing portions

107 and 109 are guided by the respective interior surfaces of

surfaces

25 and 23, and the bottom surface of serrated flange 103 is guided by its abutting relationship with flat upper surface 19. As viewed in FIGS. 7 and 8, the portion of the serrated flange 103 that extends to the right beyond the edge 123 is slightly greater than the length of the projecting point 99 that extends beyond the left edge 125 in order that, when the projecting point 99 is fully engaged in the corner 55, the serrated flange 103 will fully cover the longitudinal slot 121. Miter cuts of 90 degrees are made at the end of the mullion tube 3 to be fastened to the corner joint 55, the inserting member 63 is inserted interiorly of this mullion tube 3 and then the inserting member 63 is moved in a direction toward the comer joint 55 sufficiently to engage the projecting point 99 in the corner joint 55. To remove the mullion tube 3 fastened to comer joint 55, the inserting member is simply moved in the opposite direction to disengage the projecting point 99 from the corner joint 55. It should be appreciated that the description with respect to FIG. 6 would apply similarly to inserting

members

65, 67 and 69 and their

respective mullion tubes

5, 17 and 15, as well as with respect to other inserting members utilized to fasten other mullion tubes. The described structure of the inserting member 63 and the method of fastening permits the longitudinal axis of the mullion tube to be disposed relative to either the stile 35 or rail 39 at angles ranging from 28 to 62 degrees. This range of 28 to 62 degrees was determined to be the practical operating range at which mullion tubes would be thusly disposed to form patterns of diamond-shaped lights. This range of 28 to 62 degrees is not to be a limitation of the structure of the inserting members. The inserting members in their presently embodied structure can be utilized to fasten mullion tubes in colonial-type patterns where the mullion tubes are fastened at intersecting angles of 90. The inserting members can be utilized to fasten the mullion tubes at less than 28 and more than 62 by correspondingly lengthening the longitudinal slot 121, by correspondingly increasing the length of the serrated flange portion that extends to the right beyond the edge 123 and by correspondingly decreasing the included angle formed by the

lateral sides

117 and 119.

FIG. of the drawings shows the bevel cutting feature of the invention to provide cam or wedge locking. FIG. 4 shows that the mitered ends of mullion tubes 7 and 11 are aligned with the plane 97 and this plane is represented by reference numeral 97 applied in FIG. 10. Plane 97 also represents the correct dimensional measurement of the required length of these mullion tubes at their center portions governed by the width and height of the visible glass surface area. This correct dimensional measurement is ascertained and, instead of a miter cut being made coplanar with plane 97, a miter cut in the form of a bevel cut 127 at angle of 3 is made to pass through the center of

surfaces

23 and 25 and bisect the plane 97 limited, for purposes of explanation herein, to the dimension of upper to lower surfaces 19 to 21. This bevel cut 127 results in an overcut upper portion 129 and an undercut lower portion 131. This bevel cut is performed at the lateral side of angular joint 51 adjacent stile 35 and a similar bevel cut is performed at the lateral side of angular joint 53 adjacent stile 37. The described bevel cuts eliminate the need for inserting

members

63, 65, 67 and 69 to fasten

respective mullion tubes

3, 5, 17 and 15 to their respective corner joints 55, 57, 59 and 61. Except for these inserting members and their corresponding longitudinal slots 121, the mullion device 1 is assembled to fit and be secured to window 43. Then the

angular joints

51 and 53 are pushed downwardly such that the lower surfaces 21 of

mullion tubes

7, 9, 11 and 13 are in abutting relationship with light 45. The overcut upper portions 129 are retentively cam or wedge locked against

stiles

35 and 37, and cause axial distortions along the longitudinal axes of

mullion tubes

7, 9, 11 and 13. These axial distortions are transmitted to cross

joints

47 and 49, and which cause the mullion tubes 3, 5, 7 and 9 of cross joint 47, and

mullion tubes

11, 13, 15 and 17 of cross joint 49, to impinge against light 45 to effectuate vibration dampening of light 45 thereby minimizing window rattle and making a stronger window. The axial distortions transmitted to cross

joints

47 and 49 are further transmitted along the longitudinal axes of mullion tubes 3, 5, l5 and 17 with the further result that the mitered ends of

mullion tubes

3, 5, 17 and 15 retentively impinge against their respective corner joints 55, 57, 59 and 61. The axial distortions described herein resulting from the bevel cuts and utilized cam or wedge locking, and the transmitted axial distortions, are minimal and imperceptible to the naked eye. The bevel cuts could also be made at the ends of the

mullion tubes

3, 5, 17 and 15 which would be disposed in abutting relationship with respective comer joints 55, 57, 59 and 61 to achieve cam or wedge locking. In mullion device patterns of multiple diamondshaped lights, preferably the bevel cuts would be made at all the angular joints to uniformly distribute and transmit the resulting axial distortions. This cam or wedge locking feature can similarly be utilized and achieved for retention of the mullion tubes in patterns of colonial-type lights.

FIG. 11 of the drawings shows the rough surface 133 on an end of an angle-joint connector 89. The surface roughness is at least 50 microinches root mean square. This surface roughness is provided on

ends

91 and 93 of angle-joint connector 89 in order that ends 91 and 93 can be permanently bonded to their mullion tubes by either of two methods of heat bonding. In the first method the angle-joint connector 89 is heated to a range of between 400550 F., and the

ends

91 and 93 are inserted interiorly of the mullion tubes which remain at room temperature, and which causes the plastic of the mullion tubes to flow and heat set around the rough surfaces of

ends

91 and 93. When the plastic cools, the mullion tubes and angle-joint connector 89 are structurally bonded and united permanently. In the second method of heat-bonding, the ends 91 and 93 of the angle-joint connector 89 are inserted interiorly of the mullion tubes, and heat ranging from 400550 F. is induced into the angle-joint connector 89 by high-frequency current of a conventional high-frequency induction heater, which causes the plastic of the mullion tubes to flow and heat set around the rough surfaces 133 of

ends

91 and 93. When the plastic cools, the mullion tubes and anglejoint connector are structurally bonded and united permanently. The ends 77 and 79 of the cross-joint connectors 71 similarly would have a rough surface of at least 50 microinches root mean square, and would be structurally bonded and united permanently with their mullion tubes by either of the two methods of heat bonding described with reference to the angle-joint connector 89. As a practical matter, when the second method of heat-bonding is utilized, the mullion device 1 with its mullion tubes, cross-joint connectors and angle-joint connectors would first be assembled, and then the required heat would be induced into the cross-joint connectors 71 and angle-joint connectors 89. Of course, the

nun-1: MA!

mullion devices of colonial patterns would only have crossjoint connectors 71 joining the mullion tubes.

In FIG. 13, reference numeral 135 generally refers to the suspension grid for a ceiling in a diamond-shaped pattern, its runners and flanges, and the diamond-shaped ceiling panels disposed and carried on the flanges. The suspension grid comprises runners which intersect at angles at their cross-joints and are joined together at such cross joints by cross-joint connectors.

Cross-joint connector 137, preferably made of aluminum, is similar to cross-joint connector 71 with the exception that cross-joint connector 137 does not have the raised, shoulder portion 73 found in cross-joint connector 71.

Runner 139, shown in more detail in FIGS. 14, and 16, is of integral, one-piece construction and is made of metal or a plastic such as the type used for the mullion tubes. Runner 139 is in the shape of an inverted T. As viewed in FIG. 15, runner 139 has a vertical web 141, at the top of which is a tubular ridge 143 and at the bottom of which are two symmetrical,

transverse flanges

145 and 147 extending oppositely outwardly. Each cross joint is made of the four runners 139 whose

flanges

145 and 147 have been mitered to fit by 90 degree cuts only, without coping, and is structurally joined together by two cross-joint connectors 139.

As shown in FIGS. 13, 14 and 16, and as viewed relative to the longitudinal axes of the runners 139, it should be noted that at the ends of the runners 139 their

flanges

145 and 147 extend beyond their vertical webs 141 and tubular ridges 143 in order that, at the variety of angles at which the runners 139 may intersect, the vertical webs 141 and tubular ridges will not touch one another thereby limiting the variety of angles of the intersecting runners 139 and otherwise interfering in the assembly of the structural cross joint, and in order that space is provided, as shown in FIG. 16, in which a wire 149 secured to the ceiling can be attached or otherwise connected to the assembled cross-joint connector 137 of the cross joint, as shown.

The assembly of the crossjoint connectors 137 and runners 139 to form a structural cross joint would be similar to the described assembly of the cross-joint connectors 71 and mullion tubes to form a structural cross joint. Similarly, when a permanent structural cross joint is desired, the runners utilized would be plastic, the ends of the cross-joint connectors 137 would have a surface roughness of at least 50 microinches root mean square and one of the described methods of heat bonding would be employed. After the diamond-shaped suspension grid of intersecting runners 139 and cross-joint connectors 137 is assembled and connected to the ceiling, corresponding and complemental diamond-shaped ceiling panels 151 are disposed to be supported by the flanges by having the edges of the panels rest on the flanges, or are supported by the flanges entering kerfs in the edges of the panels. It should further be appreciated that the runners 139 and cross-joint connectors 137 in their described structural embodiments can be utilized to assemble suspension grids for square or rectangular-shaped patterns to support ceiling panels of square or rectangular shape.

In FIG. 17 of the drawings, reference numeral 153 generally refers to the geodesic structure of elongated members which are joined together at their cross joints and T-joints. Geodesic structure, in the form shown and in other forms, can be utilized structurally or decoratively to form its own curved surface or in abutting relationship against a cbmplemental surface.

The intersecting, elongated members are joined together in removable cross joints 155, 157, 159, 161, 163, 165 and 167, as shown, or as permanent cross joints. The elongated membets are similar to the mullion tubes utilized and described with reference to FIG. 1. And, the cross-joint connectors 71 utilized to join those mullion tubes together are similarly utilized to join together these elongated members at their cross joints. The previously described method of heat-bonding may be employed to make the assembled cross joints pennanent.

The intersecting, elongated members are joined together in removable T-

joints

169, 171 and 173, as shown. Likewise, the previously described methods of heat-bonding may be employed to make the assembled T-joint structures permanent.

T-joint 173 is shown in FIG. 18 and consists of

mullion tubes

175, 177 and 179, which when assembled, intersect to form a T-joint. Mullion tube 175 has one 45 degree miter cut performed on its end relative to its longitudinal axis, as shown.

Mullion tubes

177 and 179 have 45 miter cuts performed on their ends relative to their longitudinal axes, as shown.

The connectors utilized to assemble the

mullion tubes

175, 177 and 179 to form T-joint 173 consist of a cross-joint connector 181 and a T-joint connector 183.

Cross-joint connector 181 is similar to cross-joint connector 137. Connector 181 is preferably of aluminum and is of right circular cylindrical configuration, has a half-cylindrical portion removed from the middle thereby leaving a remaining portion or recess 185 and has two

ends

187 and 189. As shown in FIG. 19, the remaining portion or recess 185 is defined by a bottom wall and two end walls. The width of the bottom wall is the same as the diameter of connector 181. The length of the bottom wall is greater than its width.

T-joint connector 183 is preferably of aluminum and is of right circular cylindrical configuration, has a half-cylindrical portion removed thereby leaving a remaining portion or recess 191 and an end 193. The other end 195 is tapered and its terminal portion 197 is in the configuration of a hook, as shown. As shown in FIGS. 19 and 20, the remaining portion or recess 19] is defined by a bottom wall and two end walls. The length of the bottom wall is greater than the greatest diameter or width of T-joint connector 183.

Arbitrarily transposing the reference numerals of mullion tube 3 shown in cross section in FIG. 12 to the

mullion tubes

175 and 179 for purposes of further description, end 195 and its terminal hook portion 197 are complementally received in abutting relationship with the respective interior surfaces of

inclined webs

29 and 27.

In assembly, T-joint connector 183 is disposed relative to cross-joint connector 181 as shown in FIGS. 19 and 20. The ends of cross-joint connector 181 are inserted interiorly of

mullion tubes

175 and 179, the end 193 of T-joint connector 183 is inserted interiorly of the mullion tube 177, and then the

mullion tubes

175, 177 and 179 are disposed relative to one another such that their respective miter cuts are in abutting relationship as shown in FIG. 18.

As utilized in the claims, the term elongated member refers to either a mullion tube or a runner.

Having thusly described our invention, we claim:

1. Cross-joint structure of angularly intersecting elongated members and cross-joint connectors; said cross-joint connectors having ends and recesses, said recesses having bottom walls and end walls, said ends of said cross-joint connectors carrying said elongated members, said bottom walls being in abutting relationship, said bottom walls having lengths greater than their widths thereby permitting relative disposition of said cross-joint connectors at a variety of angles.

2. The structure in accordance with claim 1, wherein said elongated members have ends remote from their cross-joint structure for attachment to support structure and wherein said elongated members are adapted for such attachment through cam or wedge locking witI-I said support structure by bevel cutting of their remote ends.

3. The structure in accordance with claim 2, wherein said bevel-cut remote ends of said elongated members have overcut upper portions, undercut lower portions, and center portions between said overcut upper portions and undercut lower portions, and wherein said center portions correspond to the required dimensions to fit said support structure.

4. 'The structure in accordance with claim 3, wherein the bevel cuts are made at angles of 3.

5. The structure in accordance with claim 1, wherein said elongated members have ends remote from their cross-joint structure for fastening to support structure, wherein are ill further provided inserting members, wherein said remote ends of said elongated members carry said inserting members, wherein said inserting members are adapted for engagement with said support structure, and wherein said elongated members are fastened to said support structure by engagement of said inserting members with said support structure.

6. The structure in accordance with claim 5, wherein said remote ends of said elongated members interiorly carry said inserting members, wherein each inserting member has a projecting point, neck, serrated flange, main body portion and two, symmetrical, transverse wing portions, wherein said projecting point is centrally imbedded in said main body portion, wherein said transverse wing portions extend oppositely outwardly from said main body portion, have rounded lateral edges and symmetrical, angled, lateral sides, wherein said elongated members have longitudinal slots formed through their remote ends, wherein said longitudinal slot engaged said neck, wherein the width of each of said longitudinal slots in less than the width of each of said necks to thereby provide interference fit, wherein said elongated members have interior surfaces, wherein said interior surfaces guide said transverse wing portions, wherein said serrated flanges facilitate manipulation of said inserting members, wherein each of said serrated flanges has a bottom surface, wherein each of said elongated members has a flat upper surface in abbuting relationship with, and guiding, said bottom surface of said serrated flange, wherein said serrated flange covers said longitudinal slot, wherein each of said projecting points of said inserting members engages said support structure to fasten its associated elongated member with said support structure, and wherein said angled, lateral sides of said traNsverse wing portions adapt said elongated members for fastening to said support structure at a variety of angles.

7. The structure in accordance with claim 1, wherein said elongated members have angularly intersecting ends remote from their cross-joint structure, wherein are further provided angle-joint connectors, and wherein said angle-joint connectors structurally join together said angular intersecting ends of said elongated members to form angular joints.

8. The structure in accordance with claim 7, wherein each angle-joint connector is of right circular cylindrical configuration and has two ends of equal radii separated by a reduced center portion whose radius is less than the radii of said ends, wherein one remote end of an angularly intersecting elongated member interiorly receives and carries one end of an anglejoint connector and the other remote end of an angularly intersecting elongated member interiorly receives and carries the other end of said angle-joint connector, wherein said elongated members have interior surfaces, and wherein said interior surfaces have portions whose radial distances are less than the radii of said angle-joint connector ends thereby providing interference fit.

9. The structure in accordance with claim 1, wherein said elongated members are mullion tubes of a mullion device or grill simulatively converting a single-light window to multiple light, wherein each of said mullion tubes has relatively flat upper and lower surfaces symmetrically disposed with respect to each other, has relatively flat top and bottom surfaces symmetrically disposed with respect to each other, has inclined webs, one of said webs joining said flat upper surface and flat top surface, another of said webs joining said flat lower surface and flat bottom surface, and the other of said webs joining said flat bottom surface and flat upper surface, said flat upper and lower surfaces, flat top and bottom surfaces and inclined webs having interior surfaces substantially parallel to their respective outer surfaces, wherein each of said crossjoint connectors is of right circular cylindrical configuration and its said ends are of equal radii separated in the middle by a raised, shoulder portion of slightly greater radius, wherein said interior surfaces of said inclined webs have portions whose radial distances are less than the radii of said cross-joint connector ends thereby providing interference fit, wherein said raised, shoulder portion structurally functions as a limit stop to prevent further insertion of said cross-joint connector interiorly of said mullion tube upon establishment of abutting relationship of said mullion tubes.

10. The structure in accordance with claim 1, wherein said elongated members are runners adapted to form a ceiling suspension grid for holding ceiling panels, wherein each of said runners is in the shape of an inverted T, has a vertical web, at the top of which is a tubular ridge and at the bottom of which are two symmetrical, transverse flanges extending oppositely outwardly, wherein each of said cross-joint connectors is of right circular cylindrical configuration and its said ends are of equal radii, wherein said tubular ridge interiorly receives and retentively carries an end of said cross-joint connector and wherein the radius of the interior of said tubular ridge is less than the radii of said cross-joint connector ends thereby providing interference fit.

11. The structure in accordance with claim 1, wherein said intersecting elongated members form a geodesic configuration.

12. The structure in accordance with claim 11, wherein some of said elongated members angularly intersect to form T- joints, wherein are further provided T-joint connectors and cross-joint connectors, and wherein said T-joint connectors and cross-joint connectors structurally joining together said intersecting elongated members forming said T-joints form said T-joints.

13. The structure in accordance with claim 12, wherein each T-joint comprises a cross-joint connector and a T-joint connector, wherein said cross-joint connector of said T-joint has ends and a recess, said cross-joint connector recess of said T-joint having a bottom wall and end walls, said cross-joint connector ends of said T-joint carrying said elongated members, wherein said T-joint connector has ends and a recess, said T-joint connector recess having a bottom wall and end walls, wherein one T-joint connector end carries one of said elongated members, wherein the other T-joint connector end is tapered and has its terminal portion in the configuration of a hook, wherein said cross-joint connector bottom wall of said T-joint and said T-joint connector bottom wall are in abutting relationship, and wherein said terminal hook portion of said T- joint connector end is disposed relative to and hooked over said cross-joint connector bottom wall of said T-joint.

14. The structure in accordance with claim 12, wherein one of said elongated members forming said T-joint has on its end a 45 miter cut relative to its longitudinal axis, and wherein said remaining elongated members forming said T-joint have on their ends 45 miter cuts relative to their longitudinal axes.

15. An inserting member adapted for use in fastening the ends of a mullion tube to window sash structure at a variety of angles, said mullion tube end interiorly carrying said inserting member, said mullion tube having relatively flat upper and lower surfaces symmetrically disposed with respect to each other, relatively flat top and bottom surfaces symmetrically disposed with respect to each other, inclined webs, one of said webs joining said flat upper surface and flat top surface, another of said webs joining said flat top surface and flat lower surface, another of said webs joining said flat lower surface and flat bottom surface, and the other of said webs joining said flat bottom surface and flat upper surface, said flat upper and lower surfaces, flat top and bottom surfaces and inclined webs having interior surfaces substantially parallel to their respective outer surfaces, said mullion tube end having a longitudinal slot formed through said flat upper surface, said inserting member having a projecting point, neck, serrated flange, main body portion and two, symmetrical, transverse wing portions, said serrated flange, neck and transverse wing portions terminating in the common planar surface of said main body portion, said projecting point being centrally imbedded in said main body portion and extending from said common planar surface of said main body portion, said transverse wing portions extending oppositely outwardly from said main body portion, said transverse wing portions having rounded lateral edges and symmetrical, acute-angled, planar lateral sides immediately diverging from said common planar surface of said main body portion, said longitudinal slot engaging said neck, the width of said longitudinal slot being less than the width of said neck thereby providing interference fit, said interior surfaces of said flat top and bottom surfaces guiding said transverse wing portions, said serrated flange facilitating manipulation of said inserting member, said serrated flange having a bottom surface, said flat upper surface of said mullion tube being in abutting relationship with, and guiding, said bottom surface of said serrated flange, said serrated flange covering said longitudinal slot, and said projecting point being engaged with said window sash structure to fasten said mullion tube to said window sash structure.

16.Cross-joint connectors adapted for use with angularly intersecting elongated members in structurally joining together said elongated members in a cross joint, said crossjoint connectors having ends and recesses, said recesses having bottom walls and end walls, said ends of said cross-joint connectors being adapted for carrying said elongated members, said bottom walls being in abutting relationship, said bottom walls having lengths greater than their widths thereby permitting relative disposition of said cross-joint connectors at a variety of angles.

17. The structure in accordance with claim 16, wherein said recesses are of half-cylindrical configurations.

18. The structure in accordance with claim 16, wherein each of said cross-joint connectors is of right circular cylindrical configuration.

19. The structure in accordance with claim 16, wherein said cross-joint connector ends are of equal radii, wherein said elongated members have interior surfaces, wherein said crossjoint connector ends are adapted to be received interiorly by said interior surfaces of said elongated members, wherein said elongated-member interior surfaces have portions whose radii are less than the radii of said cross-joint connector ends thereby providing interference fit.

20. The structure in accordance with claim 16, wherein said cross-joint connectors have slightly raised, shoulder portions separating said cross-joint connector ends, and wherein said raised, shoulder portions structurally function as limit stops after points of limit-stop engagement of said shoulder portions interiorly of said elongated members to prevent further interior insertion of said cross-joint connectors interiorly of said elongated members upon establishment of abutting relationship of said elongated members.

21. The structure in accordance with claim 18, wherein said recesses are of half-cylindrical configuration.

22. The structure in accordance with claim 19, wherein said recesses are of half-cylindrical configuration.

23. The structure in accordance with claim 19, wherein said cross-joint connectors have slightly raised, shoulder portions separating said cross-joint connector ends, and wherein said raised, shoulder portions structurally function as limit stops after points of limit-stop engagement of said shoulder portions interiorly of said elongated members to prevent further interior insertion of said cross-joint connectors interiorly of said elongated members upon establishment of abutting relationship of said elongated members.

24. The structure in accordance with claim 23, wherein said recesses are of half-cylindrical configuration.

25. The structure in accordance with claim 23, wherein each of said cross-joint connectors is of right circular cylindrical configuration.

26. The structure in accordance with claim 16, wherein said cross-joint connector ends are of equal radii, wherein said elongated members have tubular ridges, wherein said crossjoint connector ends are adapted to be received interiorly of said tubular ridges, wherein said tubular ridges have interiors, and wherein said tubular-ridge interiors have radii less than the radii of said cross-joint connector ends thereby providing interference fit.

27. The structure in accordance with claim26, wherein said recesses are of half-cylindrical configuration.

28. A T-joint connector and a cross-joint connector adapted for use with elongated members to form a structural T-joint, said T-joint connector having ends and a recess, said recess having a bottom wall and end walls, the length of said bottom wall being greater than its width, one of said T-joint connector ends being adapted for carrying one of said elongated members, the other T-joint connector end being tapered and having its terminal portion in the configuration of a hook, said cross-joint connector having ends and a recess, said recess having a bottom wall and end walls, the length of said crossjoint connector bottom wall being greater than its width, said cross-joint connector ends being adapted for carrying said elongated members, said bottom walls of said T-joint and cross-joint connectors being in abutting relationship, said terminal hook portion of said T-joint connector being disposed relative to and hooked over said cross-joint connector bottom wall, and the greater lengths of said bottom walls of said T.- joint and cross-joint connectors relative to their respective widths permitting thereby relative disposition of said T-joint connector and cross-joint connector at a variety of angles.

29. A suspension grid for suspended ceilings and for use in holding and supporting ceiling panels of diamond shape, square shape or rectangular shape, said suspension grid comprising runners and cross-joint connectors, said cross-joint connectors having ends and recesses, said recesses having bottom walls and end walls, said cross-joint connector ends carrying said runners, said bottom walls of said cross-joint connectors being in abutting relationship, said bottom walls having lengths greater than their widths thereby permitting relative disposition of said cross-joint connectors at a variety of angles to correspondinglysupport by such relative disposition of said cross-joint connectors said ceiling panels of diamond shape, square shape or rectangular shape.

30. The structure in accordance with claim 29, wherein each of said runners is in the shape of an inverted T, has a vertical web at the top of which is a tubular ridge and at the bottom of which are two symmetrical, transverse flanges extending oppositely outwardly, wherein said tubular ridges are arranged and constructed to receive said cross-joint connector ends and to be retentively carried by said cross-joint connector ends, and wherein said cross-joint connector ends thereby carry said runners.

31. The structure in accordance with claim 30, wherein said flanges support said ceiling panels.

32. A geodesic structure having elongated members forming cross joints, said geodesic structure comprising elongated members and cross-joint connectors, said cross-joint connectors having ends and recesses, said recesses having bottom walls and end walls, said cross-joint connector ends carrying said elongated members, said bottom walls of said cross-joint connectors being in abutting relationship, said cross-joint connector bottom walls having lengths greater than their widths thereby permitting relative disposition of said cross-joint connectors at a variety of angles.

33. The structure in accordance with claim 32, wherein are further provided T-joints formed by T-joint connectors, crossjoint connectors and elongated members, and wherein each T- joint has a T-joint connector and a cross-joint connector.

34. The structure in accordance with claim 33, wherein each of said T-joint connectors has ends and a recess, wherein said T-joint connector recess has a bottom wall and end walls, wherein one T-joint connector end carries one of said elongated members, wherein the other T-joint connector end is tapered and has its terminal portion in the configuration of a hook, wherein said cross-joint connectors associated with said T-joints are similar in form and construction to said cross-joint connectors utilized for said cross joints, wherein said bottom walls of said T-joint connector and said associated cross-joint connector are in abutting relationship, and wherein said terminal hook portion of said T-joint connector end is disposed relative to and is hooked over said bottom wall of said associated cross-joint connector.

35. The structure in accordance with claim 33, wherein one of said elongated members forming said T-joint has on its end a 45 miter cut relative to its longitudinal axis, and wherein said remaining elongated members forming said T-joint have on their ends 45 miter cuts relative to their longitudinal axes.

36. The structure in accordance with claim 35, wherein said 45 degree miter cuts on the ends of said remaining elongated members are at an angle of 90 relative to each other.

nun-u

Claims

1. Cross-joint structure of angularly intersecting elongated members and cross-joint connectors; said cross-joint connectors having ends and recesses, said recesses having bottom walls and end walls, said ends of said cross-joint connectors carrying said elongated members, said bottom walls being in abutting relationship, said bottom walls having lengths greater than their widths thereby permitting relative disposition of said crossjoint connectors at a variety of angles.

2. The structure in accordance with claim 1, wherein said elongated members have ends remote from their cross-joint structure for attachment to support structure and wherein said elongated members are adapted for such attachment through cam or wedge locking witH said support structure by bevel cutting of their remote ends.

4. The structure in accordance with claim 3, wherein the bevel cuts are made at angles of 3* .

5. The structure in accordance with claim 1, wherein said elongated members have ends remote from their cross-joint structure for fastening to support structure, wherein are further provided inserting members, wherein said remote ends of said elongated members carry said inserting members, wherein said inserting members are adapted for engagement with said support structure, and wherein said elongated members are fastened to said support structure by engagement of said inserting members with said support structure.

8. The structure in accordance with claim 7, wherein each angle-joint connector is of right circular cylindrical configuration and has two ends of equal radii separated by a reduced center portion whose radius is less than the radii of said ends, wherein one remote end of an angularly intersecting elongated member interiorly receives and carries one end of an angle-joint connector and the other remote end of an angularly intersecting elongated member interiorly receives and carries the other end of said angle-joint connector, wherein said elongated members have interior surfaces, and wherein said interior surfaces have portions whose radial distances are less than the radii of said angle-joint connector ends thereby providing interference fit.

9. The structure in accordance with claim 1, wherein said elongated members are mullion tubes of a mullion device or grill simulatively converting a single-light window to multiple light, wherein each of said mullion tubes has relatively flat upper and lower surfaces symmetrically disposed with respect to each other, has relatively flat top and bottom surfaces symmetrically disposed with respect to each other, has inclined webs, one of said webs joining said flat upper surface and flat top surface, another of said webs joining said flat lower surface and flat bottom surface, and the other of said webs joining said flat bottom surface and flat upper surface, said flat upper and lower surfaces, flat top and bottom surfaces and inclined webs having interior surfaces substantially parallel to their respective outer surfaces, wherein each of said cross-joint connectors is of right circular cylindrical configuration and its said ends are of equal radii separated in the middle by a raised, shoulder portion of slightly greater radius, wherein said interior surfaces of said inclined webs have portions whose radial distances are less than the radii of said cross-joint connector ends thereby providing interference fit, wherein said raised, shoulder portion structurally functions as a limit stop to prevent further insertion of said cross-joint connector interiorly of said mullion tube upon establishment of abutting relationship of said mullion tubes.

12. The structure in accordance with claim 11, wherein some of said elongated members angularly intersect to form T-joints, wherein are further provided T-joint connectors and cross-joint connectors, and wherein said T-joint connectors and cross-joint connectors structurally joining together said intersecting elongated members forming said T-joints form said T-joints.

13. The structure in accordance with claim 12, wherein each T-joint comprises a cross-joint connector and a T-joint connector, wherein said cross-joint connector of said T-joint has ends and a recess, said cross-joint connector recess of said T-joint having a bottom wall and end walls, said cross-joint connector ends of said T-joint carrying said elongated members, wherein said T-joint connector has ends and a recess, said T-joint connector recess having a bottom wall and end walls, wherein one T-joint connector end carries one of said elongated members, wherein the other T-joinT connector end is tapered and has its terminal portion in the configuration of a hook, wherein said cross-joint connector bottom wall of said T-joint and said T-joint connector bottom wall are in abutting relationship, and wherein said terminal hook portion of said T-joint connector end is disposed relative to and hooked over said cross-joint connector bottom wall of said T-joint.

14. The structure in accordance with claim 12, wherein one of said elongated members forming said T-joint has on its end a 45* miter cut relative to its longitudinal axis, and wherein said remaining elongated members forming said T-joint have on their ends 45* miter cuts relative to their longitudinal axes.

16. Cross-joint connectors adapted for use with angularly intersecting elongated members in structurally joining together said elongated members in a cross joint, said cross-joint connectors having ends and recesses, said recesses having bottom walls and end walls, said ends of said cross-joint connectors being adapted for carrying said elongated members, said bottom walls being in abutting relationship, said bottom walls having lengths greater than their widths thereby permitting relative disposition of said cross-joint connectors at a variety of angles.

19. The structure in accordance with claim 16, wherein said cross-joint connector ends are of equal radii, wherEin said elongated members have interior surfaces, wherein said cross-joint connector ends are adapted to be received interiorly by said interior surfaces of said elongated members, wherein said elongated-member interior surfaces have portions whose radii are less than the radii of said cross-joint connector ends thereby providing interference fit.

26. The structure in accordance with claim 16, wherein said cross-joint connector ends are of equal radii, wherein said elongated members have tubular ridges, wherein said cross-joint connector ends are adapted to be received interiorly of said tubular ridges, wherein said tubular ridges have interiors, and wherein said tubular-ridge interiors have radii less than the radii of said cross-joint connector ends thereby providing interference fit.

27. The structure in accordance with claim 26, wherein said recesses are of half-cylindrical configuration.

28. A T-joint connector and a cross-joint connector adapted for use with elongated members to form a structural T-joint, said T-joint connector having ends and a recess, said recess having a bottom wall and end walls, the length of said bottom wall being greater than its width, one of said T-joint connector ends being adapted for carrying one of said elongated members, the other T-joint connector end being tapered and having its terminal portion in the configuration of a hook, said cross-joint connector having ends and a recess, said recess having a bottom wall and end walls, the length of said cross-joint connector bottom wall being greater than its width, said cross-joint connector ends being adapted for carrying said elongated members, said bottom walls of said T-joint and cross-joint connectors being in abutting relationship, said terminal hook portion of said T-joint connector being disposed relative to and hooked over said cross-joint connector bottom wall, and the greater lengths of said bottom walls of said T-joint and cross-joint connectors relative to their respective widths permitting thereby relative disposition of said T-joint connector and cross-joint connector at a variety of angles.

29. A suspension grid for suspended ceilings and for use in holding and supporting ceiling panels of diamond shape, square shape or rectangular shape, said suspension grid comprising runners and cross-joint connectors, said cross-joint connectors having ends and recesses, said recesses having bottom walls and end walls, said cross-joint connector enDs carrying said runners, said bottom walls of said cross-joint connectors being in abutting relationship, said bottom walls having lengths greater than their widths thereby permitting relative disposition of said cross-joint connectors at a variety of angles to correspondingly support by such relative disposition of said cross-joint connectors said ceiling panels of diamond shape, square shape or rectangular shape.

33. The structure in accordance with claim 32, wherein are further provided T-joints formed by T-joint connectors, cross-joint connectors and elongated members, and wherein each T-joint has a T-joint connector and a cross-joint connector.

35. The structure in accordance with claim 33, wherein one of said elongated members forming said T-joint has on its end a 45* miter cut relative to its longitudinal axis, and wherein said remaining elongated members forming said T-joint have on their ends 45* miter cuts relative to their longitudinal axes.

36. The structure in accordance with claim 35, wherein said 45 degree miter cuts on the ends of said remaining elongated members are at an angle of 90* relative to each other.