WO2012153085A1

WO2012153085A1 - Connector for component connection in a modular construction set

Info

Publication number: WO2012153085A1
Application number: PCT/GB2012/000415
Authority: WO
Inventors: Philip Ross NORMAN
Original assignee: Robosynthesis Limited
Priority date: 2011-05-06
Filing date: 2012-05-04
Publication date: 2012-11-15
Also published as: GB2490550A; GB2490550B; GB201107622D0

Abstract

A connector (10) for component connection in a modular construction set comprises a connection body of electrically insulating, for example plastics, material defining a disc (11) provided on at least one of its sides, preferably each of its sides, with an axial projection (12) having connecting means for selectable mechanical connection of the disc of another such connector in orthogonal relationship or mechanical and electrical connection of at least one other component (20, 30) in axial relationship. Such a component can be a coupling peg (20) or coupling adapter (30), which are preferably electrically conductively connectible with, respectively, an electrically conductive internal surface (17a) and an electrically conductive external surface (17b) of a sleeve (17) located in the axial projection

Description

CONNECTOR FOR COMPONENT CONNECTION IN A MODULAR CONSTRUCTION

SET

The present invention relates to a connector for component connection in a construction set and has particular reference to power supply via such a connector.

Construction sets are known in various forms for constructing assemblies or subassemblies in which the constituent parts have differing angular and rotational relationships so as to form complex modular structures in two and three dimensions. Such assemblies or subassemblies can be, for example, essentially static constructions such as models, support structures and mounts or movable or mobile constructions such as robotic assembly and fabrication tools or self-propelled robots for various purposes. A construction set focussed on enabling creation of assemblies and subassemblies with such capabilities is disclosed in International Patent Specification WO 2008093028. The components of such a set provide mechanical connectors, but if power is to be conducted through an assembly or subassembly created by the components this has to be achieved by way of separately provided conductors such as wires, which gives rise to additional cost in terms of material and labour and can create susceptibilities to failure due to conductor breakage or short-circuiting. This results in loss of operational power or interruption of data transmission channels.

It is therefore the principal object of the present invention to provide a connector intended for component connection in a modular construction set to enable not only mechanical, but also electrical connection, particularly without the use of separate electrical conductors.

Other objects and advantages of the invention will be apparent from the following description.

According to a first aspect of the present invention there is provided a connector for component connection in a modular construction set, the connector comprising a connector body of electrically insulating material defining a disc provided on at least one side thereof with an axial projection, the axial projection being provided with connecting means for a selectable one of mechanical connection of the disc of another such connector in orthogonal relationship and joint mechanical and electrical connection of at least one other component in axial relationship. A connector embodying the present invention has a dual connecting capability in that it allows not only mechanical connection of other set components in axial and orthogonal relationships, but also electrical connection - by one and the same connecting means - of a component mechanically connected in axial relationship, so that current for drive power or signal or data transmission can be conducted through the connector and axially connected component without the need for separate conductors. Integration of an electrical connection capability in this manner represents a substantial saving of material and complication when current transfer is required in a modular assembly or subassembly and reduces the susceptibility to disruption or interruption of current conduction paths, particularly by the elimination of separately provided wiring.

For preference, the connecting means comprises a sleeve engageable by way of an at least partly electrically conductive internal or external surface thereof with the at least one other component for the mechanical and electrical connection in axial relationship. A sleeve, able to function as a plug and/or a socket, represents a particularly simple form of connecting device readily capable of accommodation within the axial projection. Dual functioning as both a plug and a socket is advantageously possible in an embodiment in which the sleeve is engageable by way of at least partly electrically conductive and mutually electrically insulated internal and external surfaces thereof with the at (east one other component for the mechanical and electrical connection in axial relationship. Thus, use is made of both the internal and external surfaces of the sleeve for mechanical and electrical connection purposes, whether with one component or more than one component; in the latter case, separate components can be individually connected with the two surfaces.

The sleeve preferably comprises a substantially annular body of electrically insulating material provided with internal and external layers of electrically conductive material to form the internal and external surfaces. Provision of layers in this manner allows construction of the sleeve with the requisite conductive and insulation properties in particularly simple and economic manner. In that case, the insulating material can be an electrically non-conductive plastics material and the electrically conductive material a metallic material, whereby manufacture can be way of, for example, an injection-moulded part. For preference, the layers are provided by a coating of the electrically conductive material on the substantially annular body and the mutual electrical insulation of the internal and external surfaces of the body is provided by uncoated areas at the axial ends thereof. This form of construction can be achieved by coating, for example electroplating, the core body and then selective removal of the coating at predetermined areas by grinding or other mechanical or chemical processes.

In a preferred embodiment the internal surface of the sleeve conically tapers inwardly in a direction away from the free end of the axial projection over at least a part of the length of the sleeve to permit mechanical connection of the at least one other component by a friction couple. Such a conical taper allows a firm interference fit to be created with a suitably shaped component on insertion into the sleeve. Similarly, the external surface of the sleeve can conically taper inwardly in a direction towards the free end of the axial projection over at least a part of the length of the sleeve to permit mechanical connection of the at least one other component by a friction couple. Thus, a firm interference fit can also be produced with a suitably shaped component into which the sleeve is plugged.

For preference, the connector body has a passage axially through the disc and through the axial projection, the sleeve extending in the passage and connected with the connector body by way of webs engaged in slots in the sleeve. This represents a particularly simple method of coupling the sleeve with the connector body, particularly if the webs are formed integrally with the body. The webs are also then available for additional supporting or locating functions.

In a preferred construction of the connector the disc is provided with two such axial projections one on each side thereof, in which case the sleeve of the connecting means of each projection can be provided by a respective part of a single member. In effect, a single, generally tubular component can be located within the connector body to provide the sleeves of the connecting means on the two sides of the disc. Alternatively, the disc can be provided with the axial projection on only one side, in which case the sleeve can be mechanically and electrically connectible on the other side of the disc with a further component, including a power source or different forms of coupling elements.

The connecting means of the or each axial projection preferably comprises at least one transverse groove for receiving part of the disc of another such connector for the mechanical connection thereof in orthogonal relationship. Further details with respect to a connection of that kind are provided in WO 2008/093028. It is then advantageous if the connecting means of the or each axial projection comprises at least two such transverse grooves extending perpendicularly to one another, whereby the orthogonal relationship can be created in two different mutually perpendicular settings. In addition, the or each axial projection is preferably provided with apertures receiving or for receiving locking means extending into the region of the connecting means to lock another such connector or another component connected with the connecting means. Locking means of this kind ensure that interconnected parts, which may otherwise be coupled merely by friction, are mechanically positively secured together.

According to a second aspect of the present invention there is provided a connecting device for component connection in a modular construction set, comprising a connector according to the first aspect and a coupling peg mechanically and electrically connectible with the connecting means of the at least one projection of the connector in axial relationship and with the connecting means of the at least one projection of another such connector or with a further component.

Such a coupling peg thus represents a component - distinct from another connector - connectible with the connector and can be employed for both axial stiffening of a created assembly or subassembly and power transmission between interconnected elements.

In the case where the connecting means of the axial projection of the connector comprises the afore-mentioned sleeve the peg is preferably engageable with the internal surface of the sleeve for the mechanical and electrical connection with the connecting means, the peg thus functioning as a simple form of plug coupling. The peg itself can be made of or coated with electrically conductive material, especially metallic material, and can be economically produced by, for example, casting from aluminium or injection-moulding from plastic material and coated with copper or other metallic material.

If the internal surface of the sleeve of the connector has the afore-mentioned conical taper the peg preferably has a connecting region with an external surface substantially complementary in shape to and engageable with the internal surface of the sleeve. The peg and sleeve thus represent mutually co-operating elements of a taper coupling system. The frictional couple able to be generated in that case can be amplified if the peg has an axial through bore and is slotted in the connecting region to permit resilient contraction of the peg under pressurable engagement with the internal surface of the sleeve. With respect to coupling of the peg with another such connector or a further component the peg can be provided with two such connecting regions oriented in opposite sense, whereby the peg is insertable from either end into the sleeve and does not require any particular attention to orientation prior to insertion. In that case, the connecting regions can be separated by a collar sealably engageable with a free end of the sleeve, in particular to exclude the ingress of moisture or contaminants which may impair the electrical connection.

According to a third aspect of the present invention there is provided a connecting device for component connection in a modular construction set, comprising a connector according to the first aspect of the invention and a coupling adapter mechanically and electrically connective with the connecting means of the at least one projection of the connector in axial relationship and with the connecting means of the at least one projection of another such connector or with a further component.

Such an adapter has a function analogous to the afore-mentioned coupling peg, but can be constructed particularly for mechanically positive coupling, in conjunction with locking means, rather than primarily axial stiffening. In a case where the connecting means of the axial projection of the connector incorporates the afore-mentioned sleeve the adapter is preferably engageable with the external surface of the sleeve for the mechanical and electrical connection with the connecting means, in which case it can be employed by itself or together with the coupling peg. Similarly to the peg, the adapter can be made of or coated with electrically conductive material using the same construction techniques.

If the external surface of the sleeve of the connector has the afore-mentioned conical taper the adapter can then have a connecting region with an internal surface substantially complementary in shape to and engageable with the external surface of the sleeve, which, as in the case of the coupling peg, then forms together with the sleeve the two elements of a taper coupling system.

For preference, the adapter has an axial through bore and is slotted in the connecting region to permit resilient expansion of the adapter under pressurable engagement with the external surface of the sleeve, which ensures firm frictional interengagement resisting separation up to a certain level of axial separating load. Again, in analogous manner to the coupling peg the adapter can have two such connecting regions oriented in opposite sense so that the adapter can be fitted from either end. In terms of construction the adapter preferably comprises an annular body provided at each end region thereof with a radially extending flange, the connecting regions including the flanges and being separated by a central length portion of the annular body. It is particularly convenient, in the case of a connector with a sleeve retained by webs as described in connection with the first aspect of the invention, if these webs are engageable in slots of either one of the connecting regions of the adapter - when that region is connected with the sleeve - so as to secure the adapter against rotation relative to the connector. The webs thus have the additional function of locating the adapter in a defined rotational relationship to the connector.

The adapter flanges can also participate in a locking function, particularly if the or each axial projection of the connector is provided with apertures receiving, or for receiving, locking means co-operable with a flange received in the respective projection so as to lock the adapter in the projection.

If the connecting device comprises both the coupling peg and the coupling adapter it is advantageous if, when the peg and the adapter are both connected with the connecting means, the peg and adapter are electrically insulated from one another by an air gap. This air gap can be readily achieved by appropriate dimensioning and arrangement of the peg, the adapter and the connecting means.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which

Fig. 1 is a schematic perspective view of a connector embodying the invention in company with a separate coupling peg as a component axially connectible with the connector, the connector and peg together forming a connecting device;

Fig. 2 is a view similar to Fig. 1 , but showing the connector and peg mechanically and electrically connected in axial relationship; Fig. 3 is a view similar to Fig. 2, but additionally showing a separate coupling adapter as a component axially connectible with the connector either by itself or together with the peg, the connector and the adapter or the connector, adapter and peg together forming a connecting device;

Fig. 4 is a view similar to Fig. 3, but showing the connector and peg on the one hand and the connector and adapter on the other hand mechanically and electrically connected in axial relationship; and

Fig. 5 is a perspective view of two such connectors each mechanically and electrically connected with such a peg and such an adapter.

Referring now to the drawings there is shown in Fig. 1 a connector 10 of the kind referred to in the introduction, the connector comprising a connector body made of an electricaliy insulating material, in particular injection-moulded plastics material, and consisting of a disc 1 with an axial passage and, on each side of the disc, a hollow axial projection 12 of substantially cylindrical form. Each axial projection 12 is provided with connecting means for connection with other connectors or other components, the connecting means in part being provided by two mutually perpendicular pairs of parallel grooves 13 formed in the free end portion of the respective projection and dimensioned to receive, in a frictional interference fit, the disc 11 of another such connector 10. Two connectors 10 can thereby be mechanically connected together in orthogonal relationship.

Each projection 12 is additionally provided with four equidistantly spaced apertures 14 which each communicate with a respective one of the grooves 13 and serve to receive a locking projection of a locking clip or ring (not shown) applied to the outer circumference of the respective axial projection. The disc 1 1 has a plurality of equidistantly spaced radial slots 15 so that when the disc, with appropriate rotational orientation, is inserted into a groove 13 of another connector such a locking projection can pass through the slot. The disc 1 1 is provided in each face with at least one annular channel 16 arranged so that when a disc 1 1 of one connector 10 is inserted in a groove 13 of another connector 10 a locking projection which extends into that groove and has entered that slot can pass into the channel 16 when either the disc is rotated or the locking clip or ring with the projection is turned. The two connectors connected in mutually orthogonal relationship are then locked together. Such an orthogonal mechanical coupling of connectors, which is generally in the manner described and illustrated in WO 2008/093028, represents one connection facility offered by the connecting means of the connector 10.

The connecting means of each axial projection 12 of the connector 1 1 also provides the facility for connection of another, i.e. different, component in axial relationship both mechanically and electrically. The electrical aspect of this connection provides a means whereby current can be passed on to the connected component and for preference, by that component to a downstream component, including another connector 10. A modular assembly constructed with use of a plurality of such connectors and interconnected components can thereby incorporate integrated power transmission paths capable of conducting drive current for consumers or signals representing commands and/or data.

The connection facility offered for this purpose by the connecting means comprises a sleeve 17 which is located in at least one of the axial projections 12, but in the illustrated embodiment in both projections, and has the form of a single member extending through the axial passage of the disc 1 1 and centrally in the interior of each axial projection 12. The sleeve 7 thereby provides a respective mechanical and electrical connection facility on each side of the disc 11. The sleeve 17 comprises a substantially annular body of electrically insulating material, particularly injection-moulded plastics material, which is formed around its outer circumference with four equidistantly spaced axially extending slots each receiving a respective web 18 integral with the connector body, whereby the sleeve is fixedly connected with the connector body. As explained below, the sleeve is tapered towards its ends, whereby the slots - which are present in a central region of the sleeve - one open-ended to allow sliding reception of the webs during assembly of its connector.

The sleeve 17 has two connecting regions each associated with a respective side of the disc 11 or respective one of the axial projections 12 and each characterised by an internal surface 17a which conically tapers inwardly in direction towards the disc and an external surface 1 b which conically tapers inwardly in direction away from the disc. In effect, the thickness of the wall of the sleeve constantly narrows in direction away from the disc. Intermediate these two connecting regions, the sleeve can be substantially cylindrical, i.e. without taper. Each of the internal and external surfaces of each connecting region of the sleeve 17 is electrically conductive, which is conveniently achieved by coating the sleeve as a whole with a coating of metallic material, such as copper. The coating material can be removed, such as by grinding, at each axial end of the sleeve so as to electrically insulate the electrically conductive internal and external surfaces 17a, 17b of the sleeve connecting regions from one another by the electrically insulating material of the annular body of the sleeve.

As will be evident from the foregoing description, the conically tapered forms of the electrically conductive internal and external surfaces 17a and 17b of the sleeve offer the possibility of frictional coupling of components with coupling surfaces of complementary shapes, whereby both a firm mechanical connection and a reliable electrical connection can be achieved.

One such component is shown in Fig. 1 , namely a coupling peg 20 intended to co-operate with the internal surface 17a of the sleeve 17 and also the internal surface of the sleeve 17 of another such connector 10, as evident from the connector assembly shown in Fig. 5. The coupling peg 20 is made of or coated with electrical conductive, preferably metallic, material and comprises two connecting regions 20a and 20b each having an external surface tapering inwards towards a respective free end of the peg. The tapering external surface of each connecting region is complementary in shape to and engageable with either one of the internal surfaces 17a of the sleeve 17 of the connector. The connecting region not so engaged is available for engagement in corresponding manner with the sleeve of another such connector, whereby the peg 20 is mechanically and electrically connectible with two connectors in axial relationship as evident in Fig. 5.

Each of the tapered connecting regions 20a, 20b of the peg 20 is formed with a plurality of axial extending slots 21 which permit resilient compression of the connecting region on insertion into the sleeve 17, so as to ensure firm mechanical and electrical connection. The connecting regions are separated by a collar 22 which is provided with a silicone coating and which when a connecting region 20a or 20b of the peg is inserted into the sleeve bears against the axial end of the sleeve to provide a seal against penetration of moisture or dust, as shown in Fig. 2. The connector 10 together with the coupling peg 20 form a connecting device for connecting purposes as described.

Another component mechanically and electrically connective with the connector 10 in axial relationship is shown in Fig. 3, namely a coupling adapter 30. The adapter 30 is made of or coated with electrically conductive, preferably metallic, material and comprises an annular body 31 provided at each axial end thereof with two radially outwardly extending circular flanges 32, each of which can seat in either one of the axial projections 12 of the connector. The adapter 30 has, similarly to the peg 20, two connecting regions 30a and 30b which each include a respective one of the flanges 32 and part of the annular body 31 and which are each provided with an internal surface of complementary shape to and engageable with the conically tapering external surface 17b of either one of the connecting regions of the sleeve 17, whereby a mechanical and electrical connection of the adapter with the sleeve is created. Each connecting region 30a and 30b of the adapter is provided with a plurality of equidistantly spaced slots 33 extending radially in the associated flange and partly in the annular body 31, which allow the respective connecting region 30a or 30b to resiliency expand when the adapter 30 is plugged onto a connecting region of the sleeve 17. The resilient expansion provides a firm mechanical and secure electrical connection of the adapter 30 with the sleeve 17. The free flange 32 of the adapter 30 is available for connection with another component, including another connector 10, as evident from Fig. 5.

The flanges 32 of the adapter 30 are co-operable with the afore-mentioned projections of locking clips or rings (not shown) for securing the respective flange against axial withdrawal. The slots 33 are arranged in the flanges 32 so as to be able to receive the webs 18 connecting the sleeve 17 with the connector body of the connector 10, whereby the adapter is secured against rotation relative to the connector.

The combination of the connector 10 and the adapter 30 represents another form of connecting device for the described connecting purposes.

Fig. 4 shows the adapter 30 connected with connector 10, which also contains a connected peg 20. The peg 20 and adapter 30, mechanically and electrica/ly connected in axial relationship, are separated by an insulating air gap, whereby two discrete electrically conductive paths are available for opposite polarities. The combination of the connector 10, peg 20 and adapter 30 represents another connecting device.

The connector or any one of the connecting devices embodying the invention can be used in conjunction with like or similar components for construction of modular assemblies and sub-assemblies with a power transmission capability integrated in the parts themselves and without requiring separate current conductors such as wires. Metallisation of the sleeve 17 incorporated in the conductor 10 provides an effective means of achieving electrically conductivity whilst utilising an inexpensive mouldable base body, the material of which has insulating properties and can divide the coating into separate conductor tracks by the simple expedient of removal of the coating at end faces of the sleeve.

Claims

1 . A connector for component connection in a modular construction set, the connector comprising a connector body of electrically insulating material defining a disc provided on at least one side thereof with an axial projection, the axial projection being provided with connecting means for a selectable one of mechanical connection of the disc of another such connector in orthogonal relationship and joint mechanical and electrical connection of at least one other component in axial relationship.

2. A connector according to claim 1 , the connecting means comprising a sleeve engageable by way of an at least partly electrically conductive internal or external surface thereof with the at least one other component for the mechanical and electrical connection in axial relationship.

3. A connector according to claim 2, wherein the sleeve is engageable by way of at least partly electrically conductive and mutually electrically insulated internal and external surfaces thereof with the at least one other component for the mechanical and electrical connection in axial relationship.

4. A connector according to claim 3, wherein the sleeve comprises a substantially annular body of electrically insulating material provided with internal and external layers of electrically conductive material to form the internal and external surfaces.

5. A connector according to claim 4, wherein the insulating material is an electrically non-conductive plastics material and the electrically conductive material is metallic material.

6. A connector according to claim 4 or claim 5, wherein the layers are provided by a coating of the electrically conductive material on the substantially annular body and the mutual electrical insulation of the internal and external surfaces of the body is provided by uncoated areas at the axial ends thereof.

7. A connector according to any one of claims 2 to 6, wherein the internal surface of the sleeve conically tapers inwardly in a direction away from the free end of the axial projection over at least a part of the length of the sleeve to permit mechanical connection of the at least one other component by a friction couple.

8. A connector according to any one of claims 2 to 7, wherein the external surface of the sleeve conically tapers inwardly in a direction towards the free end of the axial projection over at least a part of the length of the sleeve to permit mechanical connection of the at least one other component by a friction couple.

9. A connector according to any one of claims 2 to 8, wherein the connector body has a passage axially through the disc and through the axial projection, the sleeve extending in the passage and connected with the connector body by way of webs engaged in slots in the sleeve.

10. A connector according to any one of claims 2 to 9, wherein the disc is provided with two such axial projections one on each side thereof, the sleeve of the connecting means of each projection being provided by a respective part of a single member.

11. A connector according to any one of claims 2 to 9, wherein the disc is provided with the axial projection on only one side thereof, the sleeve being mechanically and electrically connectible on the other side of the disc with a further component.

12. A connector according to any one of the preceding claims, wherein the connecting means of the or each axial projection comprises at least one transverse groove for receiving part of the disc of another such connector for the mechanical connection thereof in orthogonal relationship.

13. A connector according to claim 12, wherein the connecting means of the or each axial projection comprises at least two such transverse grooves extending perpendicularly to one another.

14. A connector according to any one of the preceding claims, wherein the or each axial projection is provided with apertures receiving or for receiving locking means extending into the region of the connecting means to lock another such connector or another component connected with the connecting means.

15. A connecting device for component connection in a modular construction set, comprising a connector according to any one claims 1 to 14 and a coupling peg mechanically and electrically connectible with the connecting means of the at least one projection of the connector in axial relationship and with the connecting means of the at least one projection of another such connector or with a further component.

16. A connecting device according to claim 15, wherein the connector is as claimed in any one of claims 2 to 1 and the peg is engageable with the internal surface of the sleeve for the mechanical and electrical connection with the connecting means. 7. A connecting device according to claim 16, wherein the peg is made of or coated with electrically conductive material.

18. A connecting device according to claim 16 or claim 17, wherein the connector is as claimed in claim 7 and the peg has a connecting region with an external surface substantially complementary in shape to and engageable with the internal surface of the sleeve.

19. A connecting device according to claim 18, wherein the peg has an axial through bore and is slotted in the connecting region to permit resilient contraction of the peg under pressurable engagement with the internal surface of the sleeve.

20. A connecting device according to claim 18 or claim 19, wherein the peg has two such connecting regions oriented in opposite sense.

21. A connecting device according to claim 25, wherein the connecting regions are separated by a collar sealably engageable with a free end of the sleeve.

22. A connecting device for component connection in a modular construction set, comprising a connector according to any one claims 1 to 21 and a coupling adapter mechanically and electrically connectible with the connecting means of the at least one projection of the connector in axial relationship and with the connecting means of the at least one projection of another such connector or with a further component.

23. A connecting device according to claim 22, wherein the connector is as claimed in any one of claims 2 to 11 and the adapter is engageable with the external surface of the sleeve for the mechanical and electrical connection with the connecting means.

24. A connecting device according to claim 23, wherein the adapter is made of or coated with electrically conductive material.

25. A connecting device according to claim 23 or claim 24, wherein the connector is as claimed in claim 8 and the adapter has a connecting region with an internal surface substantially complementary in shape to and engageabie with the external surface of the sleeve.

26. A connecting device according to claim 25, wherein the adapter has an axial through bore and is slotted in the connecting region to permit resilient expansion of the adapter under pressurable engagement with the external surface of the sleeve.

27. A connecting device according to claim 25 or claim 26, wherein the adapter has two such connecting regions oriented in opposite sense.

28. A connecting device according to claim 27, wherein the adapter comprises an annular body provided at each end region thereof with a radially extending flange, the connecting regions including the flanges and being separated by a central length portion of the annular body.

29. A connecting device according to claim 28 when appended to claim 26, wherein the connector is as claimed in claim 9 and the webs of the connector are so engageabie in slots of either one of the connecting regions of the adapter when that region is connected with the sleeve as to secure the adapter against rotation relative to the connector.

30. A connecting device according to claim 28 or claim 29, wherein the or each axial projection of the connector is provided with apertures receiving or for receiving locking means co-operable with a flange of the adapter received in the respective projection so as to lock the adapter in the projection.

31. A connecting device according to any one of claims 22 to 36 when appended to any one of claims 15 to 21 , wherein the peg and the adapter when both connected with the connecting means are electrically insulated from one another by an air gap.