RADIATOR SUPPORT PLUG

Abstract: A radiator support plug comprises a first portion (16, 33) adapted to be removably inserted into a fluid flow connection (35) of a radiator. A second portion (18, 37) of the plug is adapted to co-operate with a radiator supporting arrangement. The first portion may be inserted into and removed from the fluid flow connection of the radiator by means of a push fit.

Description: LASER SYSTEM WITH PROJECTED REFERENCE PATTERN FIELD OF THE INVENTION The present invention relates to a radiator support plug. BACKGROUND OF THE INVENTION Conventionally, central heating radiators are mass produced in steel. They are then suspended from a conveyor system for painting and subsequent drying or curing of the paint, in an oven. In an existing arrangement radiators are suspended by way of threaded plugs which are screwed into the fluid flow connections of a radiator. The exposed part of each plug includes a circumferential channel which enables the plug, and therefore a radiator, to be supported by an aperture, usually keyhole shaped, in a strip of metal suspended from a conveyor system. Radiators may thus be supported whilst allowing the majority of their outside surface to be exposed for painting. The plugs also prevent paint from entering radiators through their fluid flow connections. Plugs are usually inserted into all the fluid flow connections of a radiator before painting. A problem with existing plugs is that once a radiator has been painted and the paint dried or cured, the dried paint around the plug makes it difficult to unscrew it from the radiator, so that the radiator may be plumbed in. This problem is particularly acute if paint penetrates along the threaded part of the plug screwed into the radiator. This is likely if a plug is not fully screwed in. To try and overcome this problem, existing plugs are provided with a hexagonal head, so that they may be unscrewed with a spanner. However, applying sufficient force to break the paint seal to remove a plug occasionally results in the plug breaking, in which case it must be drilled out, or the radiator scrapped. Also, rotation of a plug, to remove it, can damage the paint surface around the fluid flow connection. Screwing in and out plugs is also time consuming. It is an object of the present invention to provide a means for supporting radiators for painting which overcomes or at least mitigates the above mentioned problems. STATEMENTS OF INVENTION According to the present invention there is provided a radiator support plug comprising a first portion adapted to be removably inserted into a fluid flow connection of a radiator, and a second portion adapted to co-operate with a radiator supporting arrangement, wherein the first portion may be inserted and removed with a push fit. Preferably the first and second portions are separate elements which are connectable together when said first portion is located within said fluid flow connection. Preferably the second portion of the plug defines a slot or channel to enable the plug to be supported in an aperture of a support element forming part of said radiator supporting arrangement. The aperture may be provided in a strip of metal or other material, the edge of the strip around the aperture being received into the slot or channel. The first portion of the plug may be formed from any suitable material, for instance a plastics material such as acetol. Preferably the plug includes releasable locking means to prevent removal of the plug from the fluid flow connection. In one embodiment to the present invention, the plug is formed of generally rigid material and is provided with at least one integral member movable relative to the remainder of the first portion for engagement with the inside surface of the fluid flow connection. Preferably the first portion is generally cylindrical in shape and the at least one integral member is in the form of a longitudinally extending finger resiliently deformable in a radial direction. More preferably each finger includes a radially outwardly extending projection for engagement with the inner surface of the fluid flow connection. In a preferred example of a first embodiment of the present invention, the plug is a generally cylindrical hollow body, one end of which is formed from a plurality of resilient fingers each of which includes a radially outwardly extending projection, and the second portion provides releasable locking means and is slidably mountable within said first portion to prevent said fingers being moved radially inwardly. The second portion has an outer generally cylindrical surface for fitting within the hollow body of the first portion. Part of the second portion fits closely inside the body of the first portion and, when extended into that part of the body formed from the plurality of resilient fingers, prevents fingers and the projections thereon being moved radially inwardly. In a second embodiment in accordance with the present invention the plug includes a resiliently deformable outer liner having a closed end, said liner been insertable into the fluid flow connection and the first portion being insertable into the liner to cause the liner to make sealing engagement between the inner surface of the fluid flow connection and the outer surface of the first portion. The inner wall of the liner may taper inwardly in a direction towards the base of the liner. The plug may further include a longitudinally slotted guide ring for location between the liner and the first portion. In one form the guide ring may include a single slot extending its entire length. In another form the guide ring may include a plurality of peripherally spaced apart fingers extending from one end of the ring to a position spaced from the other end of the ring, the free ends of said fingers being, in use, located between the first portion and the liner. In general a plug in accordance with the present invention is preferably operative to close the fluid flow connection into which it is inserted, thereby to prevent paint passing into the radiator through the connection when the radiator is painted. An example of the problems arising when the plug does not make a sealing connection with the inner surface of the fluid flow connection can be explained in terms of the painting steps which a typical radiator encounters. The radiator is first dipped into a bath of priming paint which is a water based paint. If there is a leaky connection between a plug and a fluid flow connection, then water may enter the interior of the radiator. The radiator is then subjected to a powder coating step during which water in the radiator is turned into steam and causes the surface of the radiator to reach a temperature at which the powder coating will not adhere to the radiator surface. Support plugs according to the present invention represent a considerable improvement over existing screw-in plugs. They are much less likely to present difficulty in removal after a radiator has been painted. This seems to be because they can simply be withdrawn, they do not need to be rotated, which also reduces the risk of damage to the paint surrounding the plug. The problem of paint penetrating along the thread of a plug is completely eliminated. They may be inserted and removed more quickly and conveniently than conventional threaded plugs. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a cross-sectional view through a conventional radiator support plug, screwed to the fluid flow connection of a central heating radiator; Figure 2 shows a cross-sectional view through a radiator support plug according to the invention, inserted into the fluid flow connection of a central heating radiator, in an unlocked state; Figure 3 shows a similar view to Figure 2, but with the plug in a locked state; Figure 4 shows a perspective view of a radiator support plug body and locking member according to the invention; Figure 5 shows a perspective view of the plug body of Figure 4 with the locking member positioned ready for insertion into the plug body; Figure 6 shows a perspective view of the plug body of Figure 4 with the locking member fully inserted; Figure 7 shows a rear view of a central heating radiator fitted with support plugs according to the invention, suspended by two strips of metal; Figure 8 shows a strip of metal similar to those shown in Figure 7; Figure 9 shows the components and assembly of a second embodiment of a radiator support plug according to the invention; Figure 10 shows the components and assembly of a third embodiment of a radiator support plug in accordance with the present invention; Figure 11 shows the components and assembly of a fourth embodiment of a radiator support plug in accordance with the present invention; and Figure 12 shows the components and assembly of a fifth embodiment of radiator support plug in accordance with the present invention. DETAILED DESCRIPTION OF THE INVENTION The invention will now be described, by way of examples only, with reference to the accompanying drawings. Figure 1 shows a conventional radiator support plug 1, screwed into a fluid flow connection 2 of a central heating radiator. The plug 1, includes an externally threaded portion 3, for engagement with the internally threaded opening 4 of the fluid flow connection 2, flange 5 which abuts the periphery of the threaded opening 4 when the plug is fully screwed in, and a hexagonal head 6 which enables the plug to be turned with a spanner. The flange 5 and hexagonal head 6 define between them a channel. A problem with this type of plug is that once a radiator has been painted and the paint dried in an oven, the plug is often difficult to remove. This is due to paint surrounding, and possibly penetrating between, the plug 1 and the fluid flow connection of the radiator. It is often necessary to use a spanner to unscrew such plugs, and this occasionally leads to the plug breaking in the fluid flow connection. Referring to Figures 2 to 6, there is shown a radiator support plug according to the invention. The same reference numerals are used to indicate corresponding parts of the plug in each figure. The plug comprises a plug body 10 which includes a hollow, generally cylindrical portion 1 1 adapted for push fit insertion into a fluid flow connection 13 of a radiator and a flange 12 arranged to lie adjacent to the periphery of the opening of the fluid flow connection 13 when the plug 10 is fully inserted. The plug body 10 is formed from a plastics material, for example, acetol. The generally cylindrical portion 1 1 of the plug body 10 includes a number of fingers 14, which, because of the material from which the plug is formed are resiliently movable radially relative to plug body 10, and preferentially return to the position in which they are illustrated. It is to be understood that any number of fingers could be used as desired or as appropriate. For example, the cylindrical body could be divided into two fingers each one being generally of the form of a semi-circular arc, in cross- section. The free end of each finger 14 includes an angled projection 14a, projecting radially outward from the plug body 10. The plug body 10 is so dimensioned that the cylindrical portion 11 fits closely within the fluid flow connection 13 of a radiator into which the plug is to be inserted but the outside diameter of the body including the projections 14a exceeds the internal diameter of the fluid flow connection. As such, when the plug body 11 is inserted into a fluid flow connection the projections 14a contact the inside of the fluid flow connection 13 and the fingers 14 are resiliently deformed radially inwardly. As such, the projections 14a are urged towards the inside surface of the fluid connection 13. Fluid flow connections 13 to radiators usually include an internally threaded portion which opens out into a region of increased internal diameter. The plug body 10, is also so dimensioned that the distance between the flange 12 and the projections 14a is similar to, or slightly exceeds that of the length of the internally threaded part of the fluid flow connection 13, into which the plug is intended to be inserted. Thus, when the plug is fully inserted into the fluid flow connection 13, so that the flange 12 abuts the periphery of the opening to the connection, then the projections 14a located at the end of each finger 14 will pass beyond the end of the internally threaded portion and will spring radially outward, back to their original position. The projections will catch on the inside of the fluid flow connection retaining the plug in place. Alternatively, if the plug body 10, is not fully inserted or if the finger 14 are shorter, relative to the length of the threaded part of the fluid flow connection, then the projections will be urged towards and engage with the threaded part of the fluid flow connection. The projections 14a, are arranged so that the plug body 10 may be removably inserted into a fluid flow connection 13. All that is required is for the plug body to be pulled with sufficient force so that the projections 14a and hence fingers 14 are deformed radially inwardly by the inside of the fluid flow connection, so that the plug body will slide out. In order that the plug body 10 may be more securely retained in place, there is also provided a locking member 15 comprising a generally cylindrical member 16, 17 with a radially projecting flange 18 and a generally circular head 18a at one end. The flange 18 and head 18a define a circumferential channel 19. The locking member 15 is slidably mounted within the plug body 10. The locking member 15 is formed from the same material as the plug body. The generally cylindrical member comprises two portion. The first portion 16, is of an external diameter which closely fits within an aperture 12a in the flange 12 of the plug body. The second portion 17, is of a greater diameter and will not pass through aperture 12a. The diameter of the second portion 17 is such that it closely fits within the plug body 10. The length of the second portion 17 corresponds to the length of the cylindrical portion 1 1 of the plug body 10 which is not formed from fingers. When the locking member 15 is withdrawn to the maximum extent from the valve body 11 , then the arms 13 may flex radially inwardly, allowing for insertion into and removal from a fluid flow connection. When the locking member is pushed home, into the plug, as shown in figure 3, then its second portion 17 prevents the fingers 14 from being flexed inwardly and hence insertion or removal of the plug. When the finger si 4 are deformed inwardly by contact with the inside of the fluid flow connection, then when the locking member 15 is pushed home it will operate to urge the projections 14a towards the inside surface of the fluid flow connection, and hence restrict removal of the plug body 10. In use, a plug is inserted into a fluid flow connection with the locking member in a withdrawn position. The locking member is then pushed home to lock the arms in place and prevent removal of the plug. A radiator may then be suspended using the plug. Once the radiator has been painted, and the paint dried, then the locking member is moved to the withdrawn position and the plug pulled out of the fluid flow connection. This is considerably easier than unscrewing a conventional threaded plug as the plug does not need to be turned, rather it can be simply pulled out. This makes in easier to break any paint seal which may have formed around the plug, as compared to a conventional threaded plug and represents a considerable improvement over the prior art. Figure 5 shows a locking member ready for insertion into a plug body through aperture 12a (not visible). The material from which the locking member 15 and plug body 10 are formed will yield sufficiently to allow portion 17 to be forced into the plug body 10, but will subsequently prevent removal of the locking member 15 from the plug body 10, during normal use of the plug. Figures 7 and 8 show how a radiator is suspended for painting using support plugs. Referring to these figures, a conventional single panel central heating radiator 20 includes four fluid flow connections 21. A radiator support plug 22 is inserted into each connection 21. Support plugs on opposite sides of the radiator are supported within key shaped holes 23 in strips of metal 24, which are suspended from a conveyor system (not shown). The above embodiment is described by way of example only. Many variations are possible without departing from the invention. For instance, rather than arranging for the plug body to be inserted and withdrawn from a fluid flow connection and locked in place with a locking member, the projections could be larger so that a locking member is not required, but joined frangibly to the arms so that a sharp pull causes them to break off or bend permanently out of position allowing the plug to be withdrawn, but not reused. Referring to Figure 9 of the accompanying drawing, a second embodiment of a radiator support plug in accordance with the present invention comprises a solid plastic plug member 31 having a first portion 33, of generally cylindrical shape, which is adapted to be removably inserted into a fluid flow connection 35 of a radiator. At one end first portion 33 of plug member 31 is chamfered and at its other end it is integrally joined to second portion 37 which is provided with two spaced apart flanges 39 and 41. These flanges together define an annular channel 43 which enables the plug to be supported by, for instance, an aperture in a strip of metal or other material forming part of a radiator supporting arrangement. The radiator support plug shown in Figure 9 includes a liner 43 in the form of a hollow rubber plug member having a base 45 and a cylindrical side wall 47. At its open end liner 43 has an outwardly extending annular flange 49. As illustrated in Figure 9, the length of liner 43 is approximately that of the threaded inner surface of the fluid flow connection 35. In use, the liner 43 is first pushed into fluid flow connection 35 and then the plastic plug member 31 is pushed constantly or intermittently, for instance by hammering into the liner 43 until the flange 41 of plug member 31 makes contact with the flange 49 of liner 43. In this position the free chamfered end of first portion 33 of plug member 31 engages the base 45 of liner 43. The outer dimension of first portion 33 of plug member 31 is greater than the inner dimension of the rubber liner 43. The rubber liner is deformable and insertion of plug member 31 into the liner causes the latter to expand into the threads of the fluid flow connection 35 thereby making a watertight joint. After painting, the plug member 31 may be pulled out of fluid flow connection 35 and the liner 43 may then easily be extracted from the fluid flow connection 35. At least the plug member 31 may then be reused. Referring to Figure 10 of the accompanying drawings, there is illustrated a radiator support plug broadly similar to that described above with reference to Figure 9. The same reference numerals will be used where appropriate. The plug includes plug member 31 in the form of a plastic plunger similar to the corresponding member in Figure 9. The plug also includes a liner 43 in the form of a rubber sock but in this case it has an inner surface which tapers inwardly from its open end at flange 49 to base 45. When the plug member 31 is inserted within liner 43, the liner wall will then tend to taper outwardly, thereby making the connection with the interior surface of a fluid flow connection increasingly effective in a direction towards the base of the liner. Referring to Figure 11 of the accompanying drawings, a further embodiment of a radiator support plug of the invention includes a solid plastic plug member 51 broadly similar to plug member 31 of the Figure 9 embodiment but having an enlarged free end portion 53. This embodiment also includes a liner 55 in the form of a rubber sock broadly similar to liner 43 of the Figure 9 embodiment. In this case, however, the end flange 57 extends not only outwardly but also inwardly and in a direction towards base 59 so that the open end of the liner 55 has a reduced diameter. In addition, this embodiment of a plug of the present invention includes a longitudinally split guide sleeve or ring 61 formed or rigid material and having a length equal to that of a distance between base 59 and the inner edge of the reduced diameter end portion of liner 55. Figure 11 shows the plug in its assembled condition with the liner 55 supported on guide ring 61 and with plug member 51 inserted within the guide ring 61. It will be appreciated that the plug can be easily located within a fluid flow connection of a radiator. The liner 55, supported on guide ring 61, is first inserted into the fluid flow connection by squeezing the outside of the liner to close guide ring 61 sufficiently to allow easy insertion. The plug member 51 is then pushed or hammered into position within guide ring 61. When the plug is to be removed from the fluid flow connection, the plug member 51 is first extracted, following which it is easy to remove the sleeve and guide ring by squeezing on the exposed end of the sleeve. Referring to Figure 12 of the accompanying drawing, a further embodiment of a radiator support plug in accordance with the present invention includes a plug member 71 which is generally similar to the corresponding plug member 51 of the Figure 1 1 embodiment. The plug is also provided with a short liner 73 in the form of a rubber cap. Additionally, the plug includes a longitudinally slotted ring 75 which is made of plastic and is of generally hollow cylindrical shape. At one end ring 75 is formed with a flange 77 which extends both radially outwardly and radially inwardly. Over most of its length ring 75 is provided with spaced apart longitudinally extending fingers 79. To insert this radiator support plug into a fluid flow connection of a radiator the plug member 71 is first inserted sufficiently into ring 75 that the enlarged end portion 81 of plug member 71 is forced past flange 77 of ring 71. The outer diameter of enlarged portion 81 is the same as the inner diameter of ring 75 beyond flange 77. The outer diameter of the main body of plug member 71 is the same as the inner diameter of flange 77. The rubber cap 73 is next pushed onto the ends of fingers 79, thereby compressing them inwardly. The entire assembly is then pushed into a fluid flow connection 83 of a radiator until flange 77 engages with the end of the fluid flow connection. Finally plug member 71 is pushed or hammered further into ring 75 until its enlarged end 81 enters rubber cap 73 and forces outwardly the fingers 79. In this way, the cylindrical wall of rubber cap 73 is forced into engagement with the inner threaded surface of fluid flow connection 83, thereby making a good sealing connection between fluid flow connection 83 and the plug. When the plug is to be removed the plug member 71 is first pulled out until the enlarged end portion 81 engages with inner edge of flange 77. This allows the ends of fingers 79 to collapse inwardly and therefore for the entire plug to be easily removable from the fluid flow connection 83.

Claims: CLAIMS 1. A radiator support plug comprising a first portion adapted to be removably inserted into a fluid flow connection of a radiator, and a second portion adapted to co-operate with a radiator supporting arrangement, wherein the first portion may be inserted and removed with a push fit. 2. A plug according to claim 1 wherein the first and second portions are separate elements which are connectable together when said first portion is located within said fluid flow connection. 3. A plug according to claim 1 or claim 2 wherein the second portion of the plug defines a slot or channel to enable the plug to be supported in an aperture of the support element forming part of said radiator supporting arrangements. 4. A plug according to any of the preceding claims wherein the plug includes a releasable locking means to prevent removal of the plug from the fluid flow connection. 5. A plug according to any of the preceding claims wherein the first portion is formed of generally rigid material and is provided with at least one integral member movable relative to the remainder of the first portion for engagement with the inside surface of the fluid flow connection. 6. A plug according to claim 5 wherein the first portion is generally cylindrical in shape and the at least one integral member is in the form of a longitudinally extending finger resiliently deformable in a radial direction. 7. A plug according to claim 6 wherein the or each finger includes a radially outwardly extending projection for engaging with the inner surface of the fluid flow connection. 8. A plug according to claim 4 wherein the first portion is a generally cylindrical hollow body one end of which is formed from a plurality of resilient fingers each of which includes a radially outwardly extending projection and the second projection provides the releasable locking means and is slidably mountable within said first portion to prevent said fingers been moved inwardly. 9. A plug according to claim 1 wherein the plug includes a resiliently deformable outer liner having a closed end, said liner being insertable into the fluid flow connection and the first portion being insertable into the liner to cause the liner to make locking and sealing engagement between the inner surface of the fluid flow connection and the outer surface of the first portion. 10. A plug according to claim 9 wherein the inner wall of the liner tapers inwardly in a direction towards the base of the liner. 11. A plug according to claim 9 or claim 10 wherein the plug further includes a longitudinally slotted ring for location between said liner and said first portion. 12. A plug according to claim 1 1 wherein said ring includes a single slot extending its entire length. 13. A plug according to claim 11 wherein said ring includes a plurality of peripherally spaced apart fingers extending from one end of the ring to a position spaced from the other end of the ring, the free ends of said fingers being, in use, located between the first portion and the liner.

Inventors: DAVIDSON PAUL ANTHONY, DAVIDSON, PAUL, ANTHONY
Applicants: DAVIDSON PAUL ANTHONY, VARLEY MARTIN, DAVIDSON, PAUL, ANTHONY, VARLEY, MARTIN
Application year: 1999
Main classification: F24D19
IPC codes: F24D19