GB2207459A

GB2207459A - Articulated connection between two plastics members

Info

Publication number: GB2207459A
Application number: GB08818156A
Authority: GB
Inventors: Willibald Kraus; Hans-Werner Ruckwardt
Original assignee: TRW United Carr GmbH and Co
Current assignee: TRW United Carr GmbH and Co
Priority date: 1987-07-30
Filing date: 1988-07-29
Publication date: 1989-02-01
Anticipated expiration: 2008-07-29
Also published as: DE3725352C2; FR2618839B1; GB8818156D0; DE3725352A1; SE470071B; SE8802761D0; FR2618839A1; CA1303309C; GB2207459B; SE8802761L; NL8801894A

Description

1 b 11 2207459 Articulated connection between two plastics members The

invention relates to an articulated connection between two plastics members such that one member is at least partially rotatable in relation to the other member.

As state of the art, one such construction is already known, for example, wherein the two plastics members, one of which is constructed in the form of a bearin- member and the other in the form of halves of clamping jaws, are connected to one another throukh a short one-piece strap hinge as an articulated connection (DE-OS 30 14 578). In such constructions which use a strap hinge as an articulated connection, it is a disadvantage that the risk of fracture of the hinge is considerable with hard material as'a result of the requiredbending range of about 900 for example. Furthermore, a material dependence on the film hinge results in a disadvantageous manner, that is to say the whole constructionhas to be adapted to the design of this hinge with regard to resilience.

With a so-called two-component injection-moulding process, a further disadvantage results in that here a material has to be used which is "adapted to the design of this hinge member.

1 2 As an alternative to this known state of the art, it is generally known to manufacture the two plastics members individually and to connect them to one another but in this case,, high production costs and costs for individual parts result. Two moulds are needed for the production of the corresponding parts and various stocks have to be kept while the two parts have to be assembled together in order to obtain a unit ready for use.

It is the object of the present invention to develop a construction of the kind mentioned at the beginning so that, independently of the material, an improvement is provided in the flexibility between two plastics members with simple and cheap production.

is The invention provides a plastics component comprising two members articulated together by a connection such that they are at least partially relatively rotatable, the connection having an outer element which is f ormed on one of the members and an inner element which is formed on the other member and which is at least partially located within the outer element, both elements being moulded in the same mould, the inner element being moulded within the outer element in the said mould. This results in the advantage of simple and cost-saving production as a result of the use of a single mould in the joint region, while the two plastics members are movably 3 connected to one another by this Joint region. Since there is no connection in the form of a hinge between the two plastics members, there is no longer any risk of fracture at the pivot point, which is an advantage. Moreover, there is no dependence on material f or the articulated connection according to the invention. The articulated connection is ideally suited for hard materials.

Since there is no material dependence f or the articulated connection according to the invention, the best materials, which render possible satisfactory adhesion between the f irst component and the second component, can be selected, particularly with a view to a two-component injection-moulding process.

If the articulated connection according to the invention has to take up relatively great forces, this can always be achieved by larger dimensioning of the inner and outer elements.

In one embodiment described hereinafter the inner element has an at least partially cylindrical outer surface for cooperation therewith but of small radius to provide a spacing between the substantially cylindrical surfaces of the elements.

In this embodiment the outer element is provided with a cavity spaced outwardly of and substantially coextensive with the substantially cylindrical inner surface thereof.

4 At least one breakable distance piece may be moulded between the two elements.

In two other embodiments described hereinafter, the connection comprises two lengthwise extending portions, the element cross-sections of one portion corresponding to that of the other portion but rotated through 1800 relative thereto.

In these embodiments, in each said portion the outer element has an inner surface configuration comprising a planar and a curved surface and the inner element has an outer surface configuration comprising a curved and a planar surface. In one of these embodiments said portions extend to each other from respective opposed ends of the connection. In the other of these embodiments said portions extend from respective opposed ends of the connection, and the elements define a cavity between said portions. 20 The above-mentioned cavity may be bounded by: (i) on the outer element, respective opposed plane surf aces disposed between the curved surf ace of the outer element in each said portion and the planar surface thereof in the other said portion. and respective further surfaces extending inwardly from said plane surfaces to said planar surfaces; and (ii) on the inner element, surfaces disposed oppositely to 1 t, 1 k v 1 said further surfaces on the outer element, and surf aces of a web interconnecting the parts of the inner element in the portions of the connection.

In another embodiment described hereinafter the outer element has a continuous inner surface defining a cavity within which said inner element is located.

As illustrated the continuous inner surface is cylindrical and said inner element has a substantially.cylindrical outer surface.

Furthermore the inner and outer elements have respective webs connecting them to the remainder of the respective members on which they are provided.

The invention also includes an articulated connection between two plastics members wherein the one member is at least partially rotatable in relation to the other member, characterised in that the articulated connection consists of a shell-shaped outer element on the one plastics member and an inner element which is at least partially encased in the outer element, on the other plastics member and that both elements are produced from one mould, being injection-moulded one inside the other.

In order that the invention may be better understood, the above-mentioned embodiments thereof, which are given by way of example only, will now be described in more detail with reference to the accompanying drawings, in which:

6 Figure 1 shows a side view of an articulated connection; Figure 2 shows the articulated connection of Figure 1 in a front view, partly broken away; Figure 3 shows another form of embodiment of the articulated connection in side view; Figure 4 shows a vertical section through the articulated connection of Figure 3 in front view; Figure 5 shows a further possible embodiment of the articulated connection in side view; Figure 6 shows a section through the articulated connection of Figure 5 in front view; Figure 7 shows a front view of a form of application of the articulated connection according to the invention in a mounting element; Figure 8 shows a further possible embodiment of the articulated connection according to the invention in front view; and Figure 9 shows a plan view of the articulated connection of Figure 8, partly broken away.

In Figure 1, a plastics member 1 is illustrated diagrammatically, which is connected to a plastics member 2 through an articulated connection 3. In this case, the articulated connection 3 consists of a shell-shaped outer element 4 on the one plastics member 1 and an inner element 5, which is pin-shaped and at least partially enclosed by the outer element c Y 7 4, on the other plastics member 2. Both elements 4 and 5 are produced from one mould being injection moulded one inside the other.

As can be seen, the outer element 4 has an inner surface which is cylindrical and the inner element 5 has a part- cylindrical outer surface for cooperation therewith, but of smaller radius to provide a spacing or gap 7. Moulded between the two elements 4 and 5 is a breakable distance piece 6 which is ruptured on action as an articulated connection so that afterwards the pin-shaped inner element 5 can move like a joint in the outer element 4 of shell- shaped construction. In order to match the pivotal characteristics better, a cavity 8 spaced outwardly and substantially coextensive with the cylindrical surface of the outer element may be provided in the outer element 4 and may be equidistant from the cylindrical surface as shown. The inner element 5 of pin-shaped construction is connected to the plastics member 2 via a web 25. The pivoting permitted by the articulated connection depends on the thickness of this web and on the size of the opening in the outer element 4 in the region of the web.

In the example of embodiment shown in Figures 3 and 4, the connection 3 comprises two lengthwise extending portions I and II..

The element cross-sections of each portion 8 corresponds to that of the other portion but is rotated through 1800 relative thereto. As illustrated, the outer element 41 in each portion I, II has an inner surface configuration comprising a planar surface 9 and a curved surface 10.

It can be seen from Figure 4. that in the portion I, the plane face 9 is situated at the top and in the portion II the plane face 9 is situated at the bottom. The curved surfaces 10 lie correspondingly diagonally in portions I and II.

Each portion I, II of the inner element 5 1 is constructed in the f orm of a pin and has an outer surface configuration comprising a curved surface 11 and a plane surf ace 12. As can again be seen f rom, Figure 4, in portion I, the plane surface 12 is at the top and is thus - situated opposite the plane face 9 of the outer element 41 whereas the curved surface 11 of the inner element 51 is situated opposite the curved face 10 of the outer element 41. There is a corresponding arrangement in portion II. There is a greater degree of freedom of the articulated connection as a result of the gaps between the surfaces 10 and 11 or 9 and 12 respectively.

The embodiment shown in Figures.5 and 6 is -similar to that shown in Figures 3 and 4 in that the connection portions I, II extend from respective opposed ends of the connection. However, whilst the 1 i t 9 portions I, II extend to meet each other at a central part of the connection in the embodiment of Figures 3 and 4, they do not do so in the embodiment of Figures 5 and 6. Instead the elements of the connection define a cavity (designated 13 in the upper portion of Figure 6 and 14 in the lower portion thereof) in the connection between the portions I and II.. As illustrated the cavity is bounded by surf aces 15 and 16 of the outer element and surfaces 17 and web 18 of the inner element.

The surfaces 15 are opposed plane surfaces disposed outwardly o;E the outer element curved surface 10 of each portion I. II and between that surface and the planar surface 9 of the other portion, the surfaces 16 extending inwardly from the surfaces 15 to the planar surfaces 9. As illustrated the surfaces 16 are at right-angles to the surfaces 15. The surfaces 17 are disposed oppositely to the faces 16 and extend outwardly f rom the web 18, which interconnects the parts of the inner element in the portions I and II of the connection, to the curved surface 11 of the inner element in each portion I. II.

In view of the provision of the cavity 13. 14 and the consequent ability for the inner and outer elements to move axially. or lengthwise, with respect to each other the connection illustrated in Figures 5 and 6 has a f urther degree of f reedom compared with X the connection of Figures 3 and 4. As will be appreciated the amount of relative axial movement depends on the size of the cavity in the axial, or lengthwise, direction of the connection.

A use of the connection shown in Figures 3 and 4 is illustrated in Figure 7, which shows a plastics component comprising a mounting member 19 to which a shell member 21 is articulated by such a connectionthe outer connection element 41 being provided on member 19 and the inner connection element being provided on member 21. Also articulated to the- member 19 is a further shell member 20. However, in this case the articulation is achieved by a non-illustrated so-called plastic or film, hinge formed by a flexible connecting region of reduced cross-section.

As can be seen, the shell member 21 can cover a large pivotal range as a result of this construction and is thus more resilient in its mobility than the shell member 20. of course, the shell member -20 could be connected to the member 19 with an articulated connection similar to the articulated connection between the shell member 21 and the mounting member 19.

A further embodiment of an articulated connection is illustrated in Figures 8 and 9. -As can be seen, in this case, the outer element 41 has a closed peripheral region which is formed by a ring 22 having c 1 11 a continuous inner surface defining a cavity within which the inner element 51 is located. This inner element is of pin-shaped construction being formed as a pin 2 3. In this case, in the drawing of Figure 8, there is a large gap between the pin 23 and the ring 22 but this could also be made smaller according to outer element 411 is 1 via a web 24; the part, secured to the the constructive design. The mounted on the plastics member inner element 5 1 ' is, f or its plastics member 2 via a web 25.

All the above-mentioned articulated connections are produced from one mould being injection-moulded one inside the other in the joint region, while the two plastics members 1 and 2 are movably connected to one another in the corresponding joint region 3. As a result of this articulated connection, there is no risk of fracture in the pivot point while, in addition, there is no dependence on material for the formation of the articulated connection which is an advantage.

lz

Claims

CLAIMS:

1. A plastics component comprising two members articulated together by a connection such that they are at least partially relatively rotatable, the connection having an outer element which is formed on one of the members and an inner element which is formed on the other member and which is at least partially located within the outer element, both elements being moulded in the same mould, the inner element being moulded within the outer element in the said mould.

2. A component as claimed in claim 1, wherein the outer element has an at least partially cylindrical inner surface and the inner element has an at least partially cylindrical outer surface for cooperation therewith but of small radius to provide a spacing between the substantially cylindrical surfaces of the elements.

3. A component as claimed in claim 2, wherein the outer element is provided with a cavity spaced outwardly of and substantially coextensive with the substantially cylindrical inner surface thereof.

4. A component as claimed in claim 1.. 2 or 3 j, 11 V 1 wherein at least one breakable distance piece is moulded between the two elements.

5. A component as claimed in claim 1, wherein said connection comprises two lengthwise extending portions, the element cross-sections of one portion corresponding to that of the other portion but rotated through 1800 relative thereto.

6. A component as claimed in claim 5. wherein in each said portion the outer element has an inner surface configuration comprising a planar and a curved surface and the inner element has an outer surface configuration comprising a curved and a planar surface.

7. A component as claimed in claim 5 or 6, wherein said portions extend to each other from respective opposed ends of the connection.

8. A component as claimed in claim 5 or 6, wherein said portions extend from respective opposed ends of the connection, and the elements define a cavity between said portions.

g. A component as claimed in claim 8, wherein said 7 ) Ll- cavity is bounded by: (i) on the outer element, respective opposed plane surfaces disposed between the curved surface of the outer element in each said portion and the planar surf ace thereof in the other said portion, and respective further surfaces extending inwardly f rom said plane surf aces to said planar surfaces; and (ii) on the inner element, surf aces disposed oppositely to said further surfaces on the outer element, and su2faces of a web interconnecting the parts of the inner element in the portions of the connection.

10. A component as claimed in claim 1, wherein the outer element has a continuous inner surface defining a cavity within which said inner element is located.

11. A component as claimed in claim 10, wherein said continuous inner surface is cylindrical and said inner element has a substantially cylindrical outer surface.

12. A component as claimed in claim 10 or 11, wherein said inner and outer elements have respective webs connecting them to the remainder of the respective members on which they are provided.

13. An articulated connection between two plastics t 1 Is- members wherein the one member is at least partially rotatable in relation to the other member, characterised in that the articulated connection (3) consists of a shell-shaped outer element (4, 41, 411) on the one plastics member (1) and an inner -element (5,51,511), which is at least partially encased in the outer element (3), on the other plastics member (2) and that both elements (4,5; 41.. 51, 411, 51) are produced from one mould, being injection-moulded one 10 inside the other.

14. An articulated connection according to claim 13, characterised in that the outer element (4) has an at least partially circular peripheral region in which the inner element (5) of pin-shaped construction is 15 enclosed with spacing (Figures 1, 2).

15. An articulated connection according to claim 13 or 14, characterised in that a breakable distance piece (6) is moulded between the two elements (4,,5) (Figures 1, 2).

16. An articulated connection according to claim 14. characterised in that the outer element (4) comprises, spaced apart from the circular peripheral region, an opening (8) surrounding this (Figures 1, 2).

H1:1

17. An articulated connection according to claim 1, characterised in that the outer and inner elements (41, 51) each comprise two regions (I, II) turned through 1800.

18. An articulated connection according to claim 17, characterised in that the respective region of the Quter element (41) is bounded by one plane and one curved end face (9, 10) and that the respective-region of the inner element (51) is constructed in the form 10 of a pin with one curved and one plane surf ace (11,, 12) (Figures 3. 4).

19. An articulated connection according to claim 17 or 18, characterised in that the respective regions (I, II) of the inner and outer elements (51, 41) 15 extend as far as the middle.

20. An articulated connection according to claim 17 or 18, characterised in that the outer and inner elements comprise an opening (13.. 14) in the middle between the two regions each turned through 1800.

21. An articulated connection according to claim 20, characterised in that the opening (13, 14) is bounded k 1 1 by a plane surface (15) spaced apart from the particular curved end face (10) and by a surface (16) disposed at right angles thereto in the outer element (41) on the one hand and by a vertical surface (17) spaced apart from the surface (16) of the outer element (41) and by a connecting member (18) between the two regions of the inner element (51) on the other hand (Figures 51 6).

22. An articulated connection according to claim 13 or 14, characterised in that the outer element (411) has a closed peripheral region in which the inner element (511) of pin- like construction is enclosed (Figures 8, 9).

23. An articulated connection according to any one of claims 13 to 23, characterised in that the inner and outer elements are each mounted on the respective plastics member (1, 2) via a web (24, 25).

24. A plastics component comprising two members articulated together by a connection which comprises inner and outer elements and which is substantially as herein described with reference to the accompanying drawings.

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