(1) TITLE OF THE INVENTION
Flexible tube clamp
(2) BACKGROUND TO THE INVENTION
The coupling of flexible tubes of a fairly stiff substance such as HDPE, of a larger than everyday diameter and that is intended to withstand a substantial pressure requires a strong connection In addition to rendering a strong connection a further aspect that is often required to be addressed is the rapidity with which such coupling can be made while the simplicity of equipment used contributes to its ease of use It is an object of this invention to provide a clamp that is robust and easy to use while resulting in a strong coupling once operativeiy fitted
(3) FIELD OF THE INVENTION
This invention relates to a clamp for securing at least one flexible tube of firm but yieldable material to a socket member used for desirable further connection of such tube
(4) PRIOR ART DESCRIPTION
Pipe couplings for coupling pipes of large diameter are known in the art According to one arrangement a collar of plastic or rubber enbeddmg electric current conducting elements is fitted to the ends of the tubes to be joined and a current passed though the collar This results in the collar being melted to the ends of the tubes to be joined This process is known in the trade as the Fusomatic method Although this method performs a proper function external equipment in the form of current generating equipment is required for its use It is often impractical to have such equipment available
(5) SUMMARY OF THE INVENTION
According to the invention there is provided a clamp for securing at least one flexible tube of firm but yieldable material to a socket member used for desirable further connection of such tube
(6) BRIEF DESCRIPTION OF THE DRAWING
The invention is now described, by way of example, with reference to the accompanying drawings In the drawings
Figure 1 shows a clamp, according to the invention, as formed into to a hoop force exerting formation, in side elevation,
Figure 2 shows the clamp as viewed in the direction of arrow A in figure 1 ,
Figure 3 shows the clamp as viewed in the direction of arrow B in figure 1 ,
Figure 4 shows the clamp according to section line C-C in figures 2 and 3,
Figure 5 shows the one of the members of the clamp of which a plurality of four are end on inter-secured into forming the clamp as shown in figures 1 to 4 however differing slightly from the figures 1 to 4 embodiment in the form of the end lips,
Figure 6 shows the member of figure 5 in side elevation,
Figure 7 shows the member in direction D in figures 5 and 6,
Figure 8 shows the clamp in sectioned side elevation as operativeiy fitted into securing tubes of flexible material via a socket member to one another, and
Figure 9 shows the clamp in sectioned side elevation as operativeiy fitted into securing a tube to a socket connection arranged for suitable futher connection
(7) DETAILED DESCRIPTION OF THE DRAWINGS
Referring to figure 1 to 7 of the drawings, a clamp according to the invention is generally indicated by reference numeral 10 The clamp 10 comprises a plurality of four similar complementing members 12 formed into a hoop force exerting formation 14 Each member 12 presents an arcuate section by way of its inwardly facing side 16 with the members 12 being securable into their combined hoop force exerting relationship via progressively tightenable securing means as provided by inter-securing formations in the form of opposite end lips 18 on each member 14 through which bores 20 are formed that come into registration with the bores 20 along end lips 18 of adjacent members 12 on end on positioning of the members 12 with respect to one another Inter-secuπng of the members 12 is thus achieved by bolting them together by means of bolts and nuts 22, as passing along registering bores 20 While figures 1 to 4 show the lips 18 as also extending beyond the outer periphery of the, figures 5 to 9 show them as only extending between the outer flanges 32 The formation of the lips 18 is only a function of the size of the clamp 10 Where it is large nuts and bolts 22 can be accomodated between the flanges 32, as shown in figures 5 to 9 When the clamp 10 is smaller the nuts and bolts 22 must be fitted outside the flanges 32 resuting in the lips 18 being formed to extend beyond the outer periphery of the flanges 32, as shown in figures 1 to 4 The clamps 10 are formed by opposite outer flanges 32 that are connected at their ends by integrally extending lips 18
The number of members 12 is determined by the requirement that each must promote adequate arcuate contiguity with the outside surface of an appropriate tube on being located there against without requiring to be forced onto such tube This is of particular importance where the material of such tube is of stiff material even though yiedable to some extent This is typically found in the case of HDPE plastic tubing The smaller the arcuate lengths of the inwardly facing sides 16 of the members 12, the larger the extent of contiguity The number of members 12 must however still be limited to a practical number It has thus been found for the specific embodiment described that four members 12 fulfill the requirement
Referring to figure 8 as well, and in one embodiment, the members 12, as extending about a central axis 24, are arranged to exert an at least non-extended area pinching action on tubes 26 fitted from opposite ends onto a socket formation 28 on being bolted into the hoop force exerting formation 14 on operative fitting of the clamp 12 This is achieved by the disposition of the arcuate sections of the members 12, as provided by their sides 16, of which each presents an integral pressure exerting formation layout provided by two arcuately extending ribs 27 extending spaced from one another by being provided by the inner sections 30 of integrally extending opposite end flanges 32 of each member 14 As the members 12 are the same, the flanges 32 and thus the ribs 27 come into alignment with one another on inter- secuπng the members 12 into the hoop force exerting formation 14 into forming fully circumferentially extending ribs 34
While centralised location of the members 12 onto a socket formation 28 on forming the formation 10 is normally no problem, centralisation may be facilitated by aligning features in the form of centrally extending arcuate grooves 36 that come into alignment with one another on securing the members 12 into the formation 10 A fully circumferential central groove is thus formed that matches with a central rib 37 on the socket formation 28 once the formation 10 is properly positioned with respect to the socket formation 28 Although the socket formation 28 shown in figure 8 presents grooves into which the ribs 27 are received on its operative fitting, as discussed below, it need not be so formed as a uniform length socket will also suffice
Referring to figures 1 to 7 and figure 9, and in another embodiment, the members 12, as extending about a central axis 38, are arranged to exert a pinching action on one tube end 40 in a similar way as in the figure 8 embodiment This is again achieved by way of a circumferential rib 42 defined by the inner part of a flange 44 that is constituted by aligned end flange sections along one end of each of the members 12 coming into alignment with one another on inter-securing the members 12 into the hoop force exerting formation 14 Where the opposite end region of the socket formation 46 makes provision for its conventional further connection by way of, for example, a screw threading (not shown), a bridging effect connection by the hoop force exerting formation 14 is achieved by the
members 12 making provision for their circumferential engagement to the socket formation 46 by way of complementing engaging formations in the form of socket engaging ribs 48 on being formed into the formation 10 Similar to the forming up of the rib 42 on the opposite end of the formation 10, the ribs 48 form up a circumferential nb 50 as provided by the inner part of an end flange To serve the desired bridging function the rib 50 comes into engagement with a circumferential groove 53 in the socket formation 46 on operative fitting of the clamp 12 When the positioning and depth of the groove 52 is suitably selected the clamp 12 used in the figure 9 embodiment is the same as that used for the figure 8 embodiment
While an ordinary socket formation can be used to connect tubes by means of the clamp 12 of the invention, use can also be made of a specifically developed socket formation 28, as shown in figure 8, that provides seating grooves 54 into which the circumferential ribs 34 formed on inter-secunng of the members 12 become seated In the process of fitting a clamp 12 the tube ends thus become sandwitched into the grooves 54 The invention thus also extends to a set comprising the clamp 10 and a socket formation 28 The same applies to the case of the figure 9 socket formation 46 forming a set in combination with the clamp 10