2. It is frequently necessary and/or desirable to releasably connect, or assemble together, rods, tubes or the like for various purposes, and to be able readily to disconnect them after the purpose for their assembly has been completed. Many and various temporary two and three-dimensional structures are constructed for many purposes but one of the most important and useful purposes for my invention is in the field of education and teaching.

3. In modem education it is frequently necessary to demonstrate to students, inter alia, the theory and practice of geometry and the use of angles in structural design and other areas. For this purpose it is desirable to be able readily to construct articles in two or three-dimensions to demonstrate what is being taught. The construction should be able to be produced quickly and cheaply from parts which are cheap and relatively easily available and usually reusable.

4. Whilst the following descriptions will be in relation to the educational applications of my invention the invention is also applicable in other fields. Other examples of such purposes include the assembly of bean-poles into"wigwams"to support climbing plants such as sweet-peas and climbing-beans by gardeners who dismantle the wigwams at the end of the growing season. Another useful application is in the construction of kites.

5. There are many construction kits on the market which are used in education to construct models, shapes, etc. to demonstrate various aspects of the subject being taught as outlined above but they are all"dedicated" and relatively inflexible when being used for'open ended'project or imaginative work. They are all based upon rigid comer joints and, to be useful for construction purposes, require various 90-degree comer joints for different situations and separate joints for angles, such as 45 degrees, therefore restricting user's choice. Altematively large unwieldy spheres are used with many holes to cater for variously angled connections. Most require the use of manufactured, pre-cut, fixed length rods which are limiting both visually and practically during construction demonstrations. I have now discovered that most of the aforesaid disadvantages can be overcome simply and cheaply using my invention.

6. My invention is a connector-module, which comprises two or more blocks, preferably formed of moulded plastic, each block containing a straight passageway through it, the connector-module being characterised in that the blocks are flexibly linked together by a flexible hinge at or near the surface of the blocks, the flexible hinge being at ninety degrees to the passageway through the blocks. The connector-modules may be formed from individual blocks which are subsequently joined together, formed as individual connector-modules, i. e. two blocks flexibly connected together or the connector-modules may be formed in lengths comprising a multiplicity of flexibly- hinged blocks which can be used in various numbers and from which individual connector-modules can be cut. The flexible hinge may be an integral part of the mouldings or applied to the blocks or connector-modules after they have been formed. The flexible joint allows for a rod inserted into the passageway in a block in a connector- module to rotate through any angle up to 180 degrees with respect to the rod inserted into the passageway in the other block of the connector-module. Whilst the passageway is usually circular in section it may be of other section e. g. square, oval or triangular. For three-dimensional constructions the blocks in the connector-module contains one or more additional holes at an angle (s), preferably 90 degrees to the passageway. The hole (s) may or may not penetrate through both walls of the connector-module.

7. For economic reasons it is preferable that the connector-modules of my invention can be used to produce both two and three-dimensional structures and, therefore, I prefer that the blocks used in the connector-modules contain both a passageway and one or more additional holes as discussed above.

8. In general the blocks/connector-modules of my invention can be made from any suitable material, e. g. wood, thermo-plastic or the like, but it is important that the flexible hinge is formed from a material which can with stand repeated flexing without failing. Whilst it is possible to use different materials for the blocks and the flexible hinges, as when the blocks are produced individually and the flexible hinge material applied afterwards, it is preferable that the same material is used for both the blocks and flexible hinge. Suitable materials for the blocks/connector- modules and the flexible hinges are polythene, nylon-6 or nylon-12 but it is preferable in my experience to use polypropylene.

9. The flexible hinge may extend over the whole side of the block (s) to which it is attached, but in general it is preferable that it is only attached to part of the length of the block. Whilst it may extend over any portion of the block it will normally extend over that part of the block through which the passageway exits. The requirement is that the flexible connection should be flexible enough to satisfy its purpose, but rigid enough to maintain its structural function. Thus the thickness of the flexible hinge may vary according to its length and to the distance between the blocks of the connector-module. Also its thickness may vary along its width between the blocks, narrowing towards the centre to produce a hinge line.

10. Generally the connector-modules of my invention are used in conjunction with wooden dowel or rod, which can be purchased in any length and cut to size as use dictates, although any other elongate article as hereinbefore discussed can be used.

11. As indicated above a two-dimensional comer joint having an angle variable between 0 and 180 degrees can be made by using a connector-module composed of two blocks, flexibly linked by a flexible hinge. Rods placed in the passageways in the two blocks can be moved through any angle up to 180 degrees relative to each other. If three more similar joints are connected together with equal length rods a square or a variable angle parallelogram can be very simply produced.

12. To convert a two-dimensional shape into three-dimensional form, three dimensional comer joints are used.

Such joints comprise a connector-module, formed of two blocks flexibly linked together by an integral flexible hinge, each block containing both a passageway and hole at angle to the passageway within it. The hole may be at any angle to the passageway but is usually 90 degrees thereto.

13. To convert from a two dimensional form to a to three-dimensional form vertical rods are placed into the holes in the three-dimensional comer joints and a further two dimensional replica of the first form is positioned above it with the vertical rods positioned in the hole in the respective three-dimensional comer joint of the upper form. The three-dimensional form may lack rigidity because of the flexible hinges, but this can be overcome by providing triangulation-rigidity by the use of extra rod (s) attached at an angle (s) between the vertical and/or horizontal rods by means of further connector-modules.

14. Although a connector-module comprising two flexibly/connected blocks is the most common form of my invention other constructions can be made that use a multiplicity of connector-modules linked together.

15. To make the assembly of structures easier, the passageway within the blocks, may include a longitudinal slot along its length to allow a length of rod to enter the passageway at one time rather i. e. a'click joint'into the passageway, rather than the rod having to be inserted from one end. Fast assembly is achieved by pushing a'click joint'over a rod, the'click joint'opens as it is pushed down then closes around the rod.

16. If it is desired to make assembled structures more permanent this can be achieved in various ways such as placing a pin through the connector and the rod or by using a screw or bolt that holds the connector-module joint to the rod or by using glue.

17. My invention allows teachers to demonstrate to their students various aspects of structural design and spatial awareness in both two and three-dimensions. It has many uses e. g. in design technology and engineering it can be used to teach the concepts of stability and the use of triangulation to provide rigidity in structures such as bridges.

In science it can be used to construct replica molecular structures and in mathematics it is useful in the teaching of developments, surface area, volume, symmetry, and practical applications can be demonstrated, e. g. in the construction of geodesic domes.

18. As part of a construction kit it can also be used to make models of vehicles, houses etc. to the user's own needs. Larger versions are useful for dismountable display structures. A significant advantage of my invention is that it can be used to build large structures quickly and it is not restricted to having to use predetermined lengths of rods. Also parts can readily be added to, or removed from, a structure without disturbing other parts. A further advantage of my invention is that users only need a few'strips'of connector-modules and some lengths of connecting rods, which are easily cut to size, to make a great variety of structures. Gone is the need to stock up with many and various connector types and different rod lengths and the connectors and rods are cheap enough to be considered as consumable items.

19. Construction of a structure is extremely fast because the two and three-dimensional joints are made simply by clicking, and/or pushing the connecting rods into place. The rods of an assembled structure can be added to or removed from quickly without disturbing the main structure.

20. All joints between a connector-module and a rod are assembled in the same plane, as opposed to other kits where the assembled parts overlap. Thus a simple frame shape, such as a square, can be assembled by laying the rods down on a flat surface ready for the connectors to be'pushed'and/or'clicked'into place, giving the user more control and the ability to work directly on a'plan drawing'.

21. The rods used can be cut to any length required, rather than restricted to fixed lengths, as provided by most kits.

22. Because of the inherent flexibility of the linkage between the connector-modules it is possible to produce items having movable parts.

23. My invention is easily integrated with other kits'parts to construct more complex items.

24. The connector-modules may be supplied with passageways of various sizes and/or sections, and thus a range of kits can easily be produced for use with various sizes and sections of rod.

25. The rods may be made from various materials such as solid wood or plastic dowel and are normally round but can replaced by other materials and/or shapes, e. g. hollow plastic or metal tubes of, oval, hexagonal or triangular section.

26. A further advantage of my invention is that the connectors can be moved along the rods by sliding and pivoting action, and no tools are required in assembly or disassembly of articles made.

REFERRING TO DRAWINGS (on Drawing pages 1 to 12) 27. Fig. 1.1 a shows a two-dimensional connector-module (1a) comprising two blocks (11) each containing a passageway (4) into which rods can be pushed. Fig. 1.1b shows an alternative to Fig. 1. la that has'click joints' (4b) and holes (6). The'plan view'diagram drawing Fig. 1. lc shows the connector-module in plan view and Fig. 1.1d shows the connector-module with the flexible hinge bent at ninety degrees. The thick black line (5) indicates the side that includes the flexible hinge.

28. Fig. 1.2a shows a two-dimensional connector-module (1b) comprising three blocks (11) each containing a passageway (4) into which rods can be pushed. Fig. 1.2b shows an alternative to Fig. 1.2a that has'click joints' (4b) and holes (6). The'plan view'diagram drawing Fig. 1.2c shows the connector-module in plan view. Fig. 1.2d and Fig 1.2e shows two other ways the flexible hinge may be flexed. The thick black line (5) indicates the side that includes the flexible hinges.

29. Fig. 1.3a shows a two-dimensional connector-module (1 c) comprising four or more blocks (11) each containing a passageway (4) into which rods can be pushed. Fig. 1.3b shows an alternative to Fig. 1.3a that has 'click joints' (4b) and holes (6). The'plan view'diagram drawing Fig. 1.2c shows the connector-module in plan view. Fig. 1.3d how the connector-module may be used using the flexible hinges. The thick black line (5) indicates the side that includes the flexible hinges 30. Fig. 2.1a shows a two-dimensional connector-module (1a) comprising two blocks (11) each containing a passageway (4) into which rods (3) have been pushed. Fig. 2.1b shows an alternative to Fig. 2.1a that has'click joints' (4b) and holes (6). Fig. 2.1c shows Fig 2.1a after it has been flexed through 90 degrees.

31. Fig. 2.2a shows a two-dimensional connector-module (1b) comprising three blocks (11) each containing a passageway (4) into which rods (3) have been pushed. Fig. 2.2b shows an alternative to Fig. 2.2a that has'click joints' (4b) and holes (6).). Fig. 2.2c shows Fig 2.2a after the outside blocks have been flexed through 90 degrees relative to the central block.

32. Fig. 2.3a shows a two-dimensional connector-module (1c) comprising four blocks (11) each containing a passageway (4) into which rods (3) have been pushed. Fig. 2.3b shows an alternative to Fig. 2.3a that has'click joints' (4b) and holes (6).

33. Fig. 3.1 a shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) and holes (6) into which rods can be pushed. Fig. 3.1 b shows an alternative to Fig. 3.1a that has 'click joints' (4b). The'plan view'drawing Fig. 3.1c shows the a three-dimensional connector-module in plan view and Fig. 3.1d shows the a three-dimensional connector-module with the flexible hinge bent at 90 degrees. The thick black line (5) indicates the side that includes the flexible hinge.

34. Fig. 3.2a shows a three-dimensional connector-module (2b) comprising three blocks (11) each containing a passageway (4) and holes (6) into which rods can be pushed. Fig. 3.2b shows an alternative to Fig. 3.2a that has 'click joints' (4b). The'plan view'drawing Fig. 3.2c shows the connector-module in plan view and Fig. 3.2d shows Fig 3.2a after the two outside blocks (11) have each been flexibly hinged through 90 degrees with respect to the centre block. The thick black line (5) indicates the side that includes the flexible hinges.

35. Fig. 3.3a shows a three-dimensional connector-module (2c) comprising four blocks (11) each containing a passageway (4) and holes (6) into which rods can be pushed. Fig. 3.3b shows an altemative to Fig. 3.2a that has 'click joints' (4b). The'plan view'drawing Fig. 3.3c shows the connector-module in plan view and Fig. 3.2d shows Fig 3.2a after the blocks (11) have each been flexibly hinged with respect to each other. The thick black line (5) indicates the side that includes the flexible hinges.

36. Fig. 3.4a represents a three-dimensional connector-module (2a) comprising five or more blocks (11) each containing a passageway (4) and holes (6) into which rods can be pushed. Fig. 3.4b shows an alternative to Fig. 3.4a that has'click joints' (4b).

37. Fig. 4.1a shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) into which rods can be inserted. Two rods are shown in the horizontal plane and a third rod is shown upright, illustrating how a three-dimensional comer can be achieved. Fig. 4.1b is the same as Fig. 4.1a except that two horizontal rods are clipped into place using click joints (4b).

38. Fig. 4.2a shows a three-dimensional connector-module (2b) comprising three blocks (11) each containing a passageway (4) into which two rods have been pushed right through the passageways (4). The two horizontal rods are shown parallel to one another and a third rod is shown vertically producing a three-dimensional form. Fig.

4.2b is using the same a three-dimensional connector-module (2b) but the two end blocks (11) have been hinged through 90 degrees using the flexible hinge (5), relative to the central block (11).

39. Fig. 5.1a shows a strip of two-dimensional connector-modules (7) as it could be manufactured. It comprises six blocks (11) each containing a passageway (4) into which rods can be pushed. The blocks being flexibly linked with a flexible hinge (5). The end user is then free to cut off the number of two-dimensional connector-modules required for a particular need.

40. Fig. 5.1b shows a strip of two-dimensional connector-modules (7) as it could be manufactured. It comprises six blocks (11) each containing a click joint (4b) into which rods can be clicked and holes (6) into which rods can be pushed. The blocks being flexibly linked with a flexible hinge (5). The end user is then free to cut off the number of three-dimensional connector-modules required for a particular need.

41. Fig. 5.2a shows a strip of three-dimensional connector-modules (8) as it could be manufactured. It comprises six blocks (11) each containing a passageway (4) and a hole (6) into which rods can be pushed. The blocks being flexibly linked with a flexible hinge (5). The end user is then free to cut off the number of three-dimensional connector-modules required for a particular need.

42. Fig. 5.2b shows a strip of three-dimensional connector-modules (8) as it could be manufactured. It comprises six blocks (11) each containing a hole (61) into which rods can be pushed and a click joint (4b) into which rods can be clicked. The blocks being flexibly linked with a flexible hinge (5). The user can cut off the number of three- dimensional connector-modules required for a particular need.

43. Fig. 5.3 shows a strip of three-dimensional connector-modules (8) with an electrical kit part (a1) ready to be plugged into two of the holes (6). This is shown to illustrate how other parts, such as electric or electronic kits can be used with this invention.

44. Fig 6. la shows the plan view of a square shape made from four two-dimensional connector-modules (1a) and four rods (3).

45. Fig. 6.1 b shows a pictorial view of the square shape as described in Fig 6.1 a. The rods (3) are assembled by pushing the rods into the passageways (4).

46. Fig. 6.1c shows a pictorial view of the square shape as described in Fig 6.1 a. The rods (3) being assembled by clicking the rods into the click joints (4b).

47. Fig 6.2a shows the plan view of a square shape made from four three-dimensional connector-modules (2a) and four rods (3).

48. Fig. 6.2b shows a pictorial view of the square shape as described in Fig 6.2a. The horizontal rods (3) are assembled by pushing the rods into the passageways (4). The vertical rods (3) are pushed into the holes (6). It illustrates how a three-dimensional square form can be made.

49. Fig. 6.2c shows a pictorial view of the square shape as described in Fig 6.2a. The horizontal rods (3) are assembled by clicking the rods into the click joints (4b). The vertical rods (3) are pushed into the holes (6). It illustrates how a three-dimensional square form can be made.

50. Fig7.1 shows how a bridge structure shape can be made using seven rods (3) and three types of connectors- modules. [either two or three-dimensional types] i. e. (1a) or (2a), (1 b) or (2b) and (1c) or (2c).

[Note- (2a) being a three-dimensional connector-module comprising two blocks. (2b) being a three-dimensional connector-module comprising three blocks. (2c) being a three-dimensional connector-module comprising four blocks.] 51. Fig. 7.2 shows how three types of connectors-module [two or three-dimensional] (1 a) or (2a), (1 b) or (2b) and (1c) or (2c) can be made into a rectangular framework together with a few rods (3). In order to make the framework rigid the diagonal strut is added as shown. [Note- (2a) being a three-dimensional connector-module comprising two blocks. (2b) being a three-dimensional connector-module comprising three blocks. (2c) being a three-dimensional connector-module comprising four blocks.] 52. Fig. 8 shows the beginnings of a fairground big wheel model. It is made up from two three-dimensional connector-modules types (2a) and (2b) together with rods (3).

53. Fig. 9.1a shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) into which rods can be pushed. Pin holes (9) are shown on the side of the two blocks into which a pin or similar can be placed in order to lock the rod and block.

54. Fig. 9.1b shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing click joints (4b) into which rods can be clicked into place. Pin holes (9) are shown in the side of the two blocks into which a pin can be placed in order to lock the rod and block.

55. Fig. 9.1c shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4b) into which rods are pushed. A drawing pin (a2) is shown pushed through the wall of the block and into the rod to lock the rod in place.

56. Fig. 9.2a shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) into which rods can be pushed. Threaded holes (10) are shown on the side of the two blocks into which bolts or set screws can be placed in order to lock the rods in place.

57. Fig. 9.2b shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing click joints (4b) into which rods can be clicked into place. Threaded holes (10) are shown on the side of the two blocks into which a bolt or set screw can be placed in order to lock the rod in place.

58. Fig. 9.2c shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4b) into which rods are placed. A set screw (a3) is shown in use in one of the blocks (11) to hold the rod (3) in place.

59. Fig. 9.3a shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4). The right hand rod (3) is smaller than the passageway allowing the rod to act as an axle. The left hand rod (3) is hollow and held in the passageway. Inside this rod is a shaft (a5) that can freely rotate.

60. Fig. 9.3b shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a click joint (4b). The right hand rod (3) is smaller than the passageway allowing the rod to tum and act as an axle.

The left hand rod (3) is hollow and held in the passageway. Inside the hollow rod is a shaft (a5) that can freely rotate.

61. Fig. 10. la shows a three-dimensional connector-module (2a) comprising two blocks (11) with rods placed inside them. The blocks being linked together with a flexible hinge (5).

62. Fig. 10.1b shows a three-dimensional connector-module (2a) comprising two blocks (11) with rods placed inside them. The dotted lines indicate the range of movement the top rod (3) can move relative to the bottom rod.

The range of movement shown ranges from 0 to 180 degrees.

63. Fig. 10.2a shows a three-dimensional connector-module (2a) comprising three blocks (11) with three rods (3) placed inside them. The maximum movement is shown. The arrows indicate the range of movement the each rod can make relative to each other.

64. Fig. 10.2b shows a three-dimensional connector-module (2a) comprising three blocks (11) with one long rod placed through the two outside blocks (11). The effect is that the vertical rod is fixed at 90 degrees to the long rod.

65. Fig. 10.3a shows a three-dimensional connector-module (2a) comprising four blocks (11) with four rods (3) placed inside them. A range of movement is shown.

66. Fig. 10.3b shows a three-dimenional connector-module (2a) comprising four blocks (11) with one long rod placed through the two outside blocks (11). The effect being that the two middle blocks and the rods contained therein are fixed relative to the long horizontal rod.

67. Fig. 11.1 shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) and additional holes (6). The shape of the blocks being a square form with a tube form on top for the hole (6).

68. Fig. 11.2 shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) and additional holes (6). The shape of the blocks being a square form with a truncated form on top for the hole (6).

69. Fig. 11.3 shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) and additional holes (6). The shape of the blocks being a long square upright prism form.

70. Fig. 11.4 shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) and additional holes (6). The shape of the blocks being rounds upright prisms.

71. Fig. 11.5 shows a three-dimensional connector-module (2a) comprising two blocks (11) each containing a passageway (4) and additional holes (6). The shape of the blocks being made up from an intersecting round upright prism and a horizontal round prism. 72. Fig. 12.1 shows plan view of a three-dimensional connector-module (2a) comprising two blocks (11) with two holes (6). The flexible hinge (5) has a bend focus at the hinge line (12).

73. Fig. 12.2 shows a selection of possible hole (6) shapes and various shaped rods (3) placed in the holes.