The present invention has been developed for application in a production line of the kind that includes a rotatable table or disc and a number of production line working stations, disposed around the periphery of the disc, either completely or partially above the upper peripheral surface of said disc.

A series of open chain links, which together will ultimately form a chain structure, are fed down to the edge region of the table or disc, with the open links loosely linked together, prior to said open links being closed by welding in a link- welding arrangement, whereafter the links are cooled and their temperature low- ered in a link-cooling arrangement.

Such positioning of the links on an edge region of the rotatable or pivotal disc is described and illustrated more specifically in Swedish Patent Application No. 0003587-3, filed on October 4,2000, with the title"A chain feeding arrange- ment".

This open-link chain is then fed through a link welding arrangement by the rotational movement of the disc, and then fed to a link-cooling arrangement.

A link-welding arrangement is described and illustrated more specifically in Swedish Patent Application No. 0004064-2, filed on the same day as the above mentioned patent application, with the title"A link-welding arrangement".

Such a production line also includes an arrangement for removing burrs or slag formed during the welding process.

Such an arrangement is described and illustrated in more detail in Swed- ish Patent Application No. 0003879-4, filed on October 25,2000, with the title"An arrangement for removing burrs".

As in the case of earlier techniques, the inventive link-cooling arrangement is based on the use of means for lowering the temperature of the welded links in the chain with the aid of an inert cooling gas.

Description of the prior art Several different designs of such link-cooling arrangements that use an inert cooling gas to lower the temperature of the welded chain links are known to the art.

With respect to the known prior art in a production line, particularly in- tended for the present invention, reference is made to the contents of the Interna- tional Patent Application PCT/SE 83/00371, having the International Patent Appli- cation number WO 84/01788.

This publication illustrates and describes a method and apparatus for pro- ducing non-allergenic objects, particularly objects made from metals that are in- tended for direct contact with the skin of a living creature, wherewith the present invention is also intended to fulfil such requirements.

By way of example of objects of this nature can be mentioned chains of different kinds that have different link structures, necklaces, bracelets, armbands, earring and/or nose rings, pieces of jewellery, watches, spectacles, etc., where completely pure metal, particularly precious metals such as gold, silver, platinum, palladium or rhodium, are alloyed with optimally pure sink, copper, aluminium, nickel or chromium, and where treatment processes carried out within heating and cooling stations are performed without access to air and without any contact with surface reacting substances, such as salts or acids, but take place in an inert envi- ronment.

The heating and cooling processes will preferably be carried out with the use of a protecting or shielding gas.

This prior publication teaches a production line for producing a flexible chain that contains a series of closed links, from a series of chain-orientated open links.

This production line includes workings stations, to which a first station, in which open links chain structure are positioned onto the disc to form an elongated orientation, a second station, in which mutually facing end surfaces of respective open links are welded together to form closed links, a third station, in which the newly welded links are cooled, and a fourth station, in which cooled links in a chain structure is fed from the production line.

More specifically, it is shown that in order to be able to carry out the method it is necessary for the arrangement to include a rotatable or pivotal table

or disc (61) so as to allow cold-worked objects (66), in the form of an open-linked chain structure, to pass through a link welding arrangement (63) or channel, while using a heating gas and/or a protecting or shielding gas (70), and also to include a subsequent link-cooling arrangement (68) or cooling channel, which utilises waste gases taken from the link welding arrangement (63) and passed as a cooling and a protecting and shielding gas through channels (71,73) during the cooling se- quence, wherewith displacement of the object (66) in the cooling channel takes place concurrently with the supply of said cooling and shielding gas.

Figure 7 of the drawings in this prior patent application can be considered of particular significance with regard to the earlier standpoint of techniques in rela- tion to the present invention.

Summary of the invention Technical problem When taking into consideration the technical deliberations that a person skilled in this particular art must make in order to provide a solution to one or more technical problems that he/she encounters, it will be seen that on the one hand it is necessary initially to realise the measures and/or the sequence of measures that must be undertaken to this end, and on the other hand to realise which means is/are required in solving one or more of said problems. On this basis, it will be evident that the technical problems listed are highly relevant to the develop- ment of the present invention.

When considering the earlier standpoint of techniques, as described above, it will be seen that a technical problem resides in providing a link-cooling arrangement that can be used directly in a production line, in which a series of closed links that form a chain can be produced from a series of open links, by cre- ating conditions, via the link-cooling arrangement, immediately followed by a link- welding arrangement, which utilise the fact that said link-cooling arrangement con- sists of at least one, preferably several, helical cooled gas conducting surfaces, whose inwardly facing edge lines are adapted to co-act with one or more helical pipes, intended for conducting a cooling fluid, and causing the closed-link chain to pass through an aperture or recess, formed in said gas conducting surface.

Another technical problem is one of creating with the aid of simple meas- ures in a link-cooling arrangement conditions which allow the cooling effect in said

arrangement to be adapted to take up an adapted amount of thermal energy from the links and therewith lower the link temperature in an inert atmosphere, resulting in the formation of intact closed links at the end of the link-cooling arrangement.

In addition, a technical problem resides in the ability to realise the signifi- cance of and the advantages associated with allowing said link-cooling arrange- ment to consist of a plurality of parallel helical gas conducting surfaces, whose in- wardly facing edge lines are adapted for co-action in a corresponding plurality of parallel helical pipes, intended to conduct cooling media in accordance with the counter flow principle, wherewith closed chain links are adapted to pass through apertures or recesses, formed in said gas conducting surface.

Another technical problem resides in the ability to realise the significance of and the advantages afforded by giving said aperture or recess a curvature that corresponds to a part of a radius of a rotatable table or disc.

A further technical problem resides in the ability to realise the significance of the advantages afforded by adapting said gas conducting surface for edge-line- related co-action with said pipe in a region located within and adjacent to the boundary surface of an adjacent pipe section.

A further technical problem resides in the ability to realise the significance of and the advantages afforded by guiding the cooling gas between said surfaces, and by surrounding the edge lines of said surfaces with a casing, that has the form of part of a torus-shaped casing.

Another technical problem resides in the ability to realise the significance of and the advantages afforded by causing a plurality of parallel gas streams in said casing to flow in a direction opposite to a chosen flow direction of gas cooling fluid in a corresponding number of parallel pipes.

A further technical problem is one of being able to realise the significance of and the advantages afforded by choosing said number of helical gas conduct- ing surfaces from between 2 and 5 parallel-related continuously helical wall por- tions.

Another technical problem resides in the ability to realise the significance of and the advantages afforded by choosing said helical fluid conducting pipes in a number ranging between 2 and 5 parallel-related continuously helical pipe sec- tions.

Another technical problem is one of realising the significance of and the

advantages afforded by allowing some of said cooling gas to consist of part of the waste gases, obtained from an upstream link-welding arrangement, and cooling the waste gases used to this end.

Another technical problem resides in the ability to realise the significance of and the advantages afforded by cooling said gas to a temperature around and preferably beneath 0°C, and by cooling said fluid to a temperature around and preferably somewhat above 0°C.

A further technical problem resides in the ability to realise the significance of and the advantages afforded by giving the torus-formed casing along the pe- ripheral surface region of the disc an extension, corresponding to an angle of be- tween 110° and 140°, preferably about 130°.

Yet another technical problem resides in the ability to realise the signifi- cance of and the advantages afforded by giving the torus-formed casing a diame- ter which in relation to the disc diameter has values lying between 5/45 and 10/45, such as about 6/45.

Solution The present invention thus takes as its starting point a link-cooling ar- rangement for inclusion in a production line for producing from a series of open links a series of closed links such as to form a chain.

The link-cooling arrangement is preferably adapted for inclusion as a part of a production line, which utilises a rotatable table or disc to whose peripheral edge region there is fed an open-link chain structure with the individual chain links loosely linked together, wherein said links are advanced to a link-welding ar- rangement through the rotational movement of the disc, and from there to a link- cooling arrangement in accordance with the present invention, and then to an ar- rangement for removing slag or burrs, wherein, with the intention of solving one or more of the aforesaid technical problems, the link-cooling arrangement is com- prised of one or more helical cooling-gas conducting surfaces, whose respective inwardly facing edge lines are adapted to co-act with one or more helical pipes, that function to conduct a cooling fluid, and wherein the closed-link chain is adapted to pass through an aperture or recess formed in said gas conducting sur- faces.

By way of suggested embodiments, that lie within the scope of the present

invention, it is proposed that said aperture or recess is given a curvature that cor- responds to a part of a radius of the rotatable disc.

It is also proposed that said gas conducting surfaces shall be adapted for co-action with said pipes within a region located within the boundary surface of adjacent pipes.

It is also proposed that the gas can be conducted between said surfaces, and that said surfaces are surrounded by a casing, formed by part of a torus..

The gas is caused to flow in said casing in a direction opposite to the cho- sen flow direction of said fluid.

It is also proposed that the number of helical gas conducting surfaces is chosen from between 2 and 5 parallel-related continuously helical wall portions.

It is also proposed that the number of helical fluid conducting pipes is cho- sen to be between 2 and 5 parallel-related continuously helical pipe portions.

The cooling gas is comprised of cooled waste gases taken from an up- stream link welding arrangement.

This gas is cooled to a temperature of about 0°C, preferably beneath 0°C, and said fluid is cooled to a temperature of about 0°C, preferably somewhat above 0°C.

It is also proposed that the casing, which has a part-torus shape, is given along the peripheral surface region of the disc an extension corresponding to an angle of between 110 and 140°, preferably about 130°.

It is also proposed that the casing is given a diameter, which in relation to the diameter of the disc has the values lying between 5/45 and 10/45, such as about 6/45.

Advantages Those advantages primarily characteristic of an inventive link-cooling ar- rangement reside in the creation of conditions for achieving highly effective se- quential cooling of links, welded in a link-welding arrangement so that conditions can be created in a simple manner at the end of the link-cooling arrangement such that the amount of thermal energy, that has been taken successively from the links, has been adapted so as not only to achieve an adapted low temperature at the end of the arrangement, but that cooling has also been achieved in an atmosphere in which the links are intact.

The primary characteristic features of an inventive link-cooling arrange- ment are set forth in the characterising clause of the accompanying claim 1.

Brief description of the drawings A link-cooling arrangement at present preferred and having features sig- nificant of the present invention will now be described in more detail with reference to the accompanying drawings, in which; Figure 1 illustrates a production line that includes a number of working sta- tions for producing, from a series of open chain links structure, a flexible chain consisting of a series of closed links, while using, i. a., a link-welding arrangement and an inventive link-cooling arrange- ment as working stations; Figure 2 is a horizontal view of the casing for an inventive link-cooling ar- rangement; Figure 3 is a side view of the arrangement shown in fig. 2; Figure 4 is a sectioned side view showing co-ordination between three helical waste gas conducting surfaces and helical pipes; Figure 5 is an enlarged view of a part shown in fig. 4; Figure 6 shows one of three helical surfaces used to conduct cooled waste gases; and Figure 7 shows one of three helical pipes used to conduct cooling medium.

Description of an embodiment at present preferred It will be noted that in the following description of an exemplary embodi- ment at present preferred and having the significant characteristic features of the invention illustrated in the various figures of the accompanying drawings, there have been used particularly terms and a particular terminology with the primary in- tention of clarifying the inventive concept.

However, the expressions and terms used shall not be seen as limiting the scope of the invention, and it will be understood that each term chosen shall be in- terpreted to include all technical equivalents that function in the same or essential- ly the same way, so as to be able to achieve the same or essentially the same in-

tention and/or technical effect.

Illustrated in fig. 1 is a production line 1 for producing a chain 2 consisting of a series of closed links, from a series of open links structure, forming a chain co-ordination 2'.

The open links in fig. 1 are referenced 21', 22'and 23'respectively, while the closed links are referenced 21,22, and 23.

The welds 21 a, 22a made in openings 21 a', 22a'and closing the links 21, 22 are made in a link-welding arrangement.

The open links 21', 22'and 23'are fed down onto a planar upper surface 3'of a rotatable table or disc 3, in a position referenced 3a.

The down feed of the chain co-ordination consisting of open links 21', 22', 23'is illustrated and described in more detail in Swedish Patent Application No. 00 03587-3, filed on October 4,2000, the contents of which application shall be con- sidered as forming part of the instant or present application, so as to make more apparent an appropriate use application of the present invention in a production line, that includes mutually sequential working stations.

The open-link chain 2'resting on the planar upper surface 3'of the disc 3 is transported, section by section, through a working station that functions as a welding or soldering station 31, and a following cooling station 32, wherewith the chain now consisting of mutually joined and closed links 21,22,23 is advanced along a radius-related circular section 3b of the disc 3.

A link-welding arrangement is illustrated and described in more detail in Swedish Patent Application No. 00 04064-2, filed on the same day as the applica- tion mentioned above, with the title"Link-welding arrangement", wherewith the contents of said application shall be considered as forming part of the present ap- plication, so as to make more apparent an appropriate use application of the pre- sent invention in a production line, that includes mutually sequential working sta- tions.

Thus, the chain 2, consisting of a series of closed links 21,22,23, shall be adapted for transportation in an arc along the surface section 3b of the rotatable disc 3.

A chain deflecting roller 4 is adapted to move the chain 2 and its chain sections from the upper planar surface 3'of the disc 3 radially outwards from said disc 3 in an arcuate path, and out over the rounded edge 3c of the disc 3.

In this regard, there is utilised the rotational movement of the deflecting roller 4 about its centre axis 4c, in the direction of the arrow.

This arrangement also includes an abrasive disc 6, which functions to abrade any burrs or slag that may have fastened to the planar surface 3'of the disc 3.

In the illustrated case, the chain 2 includes a section 2a, which leaves the link-cooling arrangement 32 and which has a section 2c that shall be curved around the deflecting roller 4, and also a section 2e which, as a result of its intrin- sic weight, presses the section 2c against the peripheral surface 4a of the roller 4.

Deflection 2c of the closed-link chain 2 around the deflecting roller 4 with pertinent devices forms a working station for removing slag and/or burrs that have adhered to the links in the welding station 31.

This arrangement is illustrated and described in more detail in Swedish Patent Application No. 00 03879-4, filed on October 25,2000, with the title"An ar- rangement for removing burrs", wherewith the contents of this application shall be considered to form part of the instant or present application, so as to make more apparent an appropriate use application of the present invention in a production line that includes mutually sequential working stations.

The present invention thus relates to a link-cooling arrangement 32 that can be used in the production line shown in fig. 1 and having the illustrated work- ing stations (3a, 31,32 and 4).

As will be seen from fig. 2, the link-cooling arrangement 32 includes a cas- ing 32a that has an inlet opening 32b in an upstream oriented or situated end por- tion 32c, and an outlet opening 32b'in a downstream oriented or situated end part 32d.

The casing 32a has an outer shape corresponding to part of a torus..

Located adjacent the downstream end-part 32d are a number of connec- tions 32e, three such connections in the illustrated case, which are connected to cooling fluid hoses.

Located adjacent the upstream end part 32b is a connection 32f by means of which a cooled inert gas is delivered to the arrangement 32.

This cooled inert gas consists of gas portion taken from the waste gases formed in an upstream link-welding arrangement 31.

Attached to the casing 32a, adjacent the end part 32c, is a connection

32e'for"shunted"fluid. Attached to the casing 32a, adjacent the end part 32d, is a connection 32f'for conducting away waste gases.

The structural design of the link-cooling arrangement 32 will now be de- scribed in more detail with reference to figs. 4 to 7.

The arrangement 32 consists partly of one or more pipe sections, three in the case of the illustrated example.

One pipe shall be wound tightly with a constant radius of curvature and a constant pitch, such as to form a helix.

Two pipes shall be orientated parallel with one another and wound tightly with a constant radius of curvature and a constant pitch, wherein one of said pipes forms a helix, whose pitch is twice that of the pitch of one other pipe.

Figure 7 shows one pipe 32k of the three pipes used, with a constant ra- dius"r"of curvature and with a pitch"s", which is adapted so at to enable two fur- ther such pipes to be inserted in the helical form, shown in fig. 7, as illustrated in figs. 4 and 5.

Shown in fig. 6 is one of three gas conducting flanges 32n, that have mu- tually opposite gas conducting surfaces 32n', 32n".

The illustrated flange 32n has a constant radius of curvature"r1", which corresponds generally to the radius of curvature of a virtual cylinder, surrounding the pipe 32k.

Also in this case there is shown a pitch"s", which is adapted so as to en- able two further flanges 320, 32p to be inserted into the helical form, shown in fig.

6.

The co-ordination of three pipes 32k, 321 and 32m having three flanges 32n, 32o and 32p will best be seen from fig. 5.

The inner edge line 32na of the flange 32n is adapted for co-action with the pipe 32k, and the outer edge line 32nb of the flange 32n is adapted for co- action with the inner surface 32a'of the casing 32a.

Thus, the present invention comprises one or a number of helical gas conducting surfaces 32n'and 32n"respectively, wherewith the inwardly facing edge line 32na of said surfaces is adapted for co-action with a helical pipe 32k, and more specifically orientated between adjacent pipes.

These pipes are thus intended to conduct cooling fluid, such as water, and to dissipate thermal energy, taken up by the flanges, from the newly welded links.

The closed chain-links 21,22,23 are adapted to pass through a recess or aperture, formed in the gas conducting surface.

A line 60, in fig. 6, indicates that for each turn of the flange 32n (and natu- rally also of the other flanges 320, 32p) the flange has been formed with an aper- ture within a surface region adjacent the disc 3, where the dimension of said aper- ture only slightly exceeds the cross-sectional dimension of the links.

Thus, the casing 32a is provided with a slot adjacent the disc, such as to form said aperture.

The aperture has a curvature"R1"corresponding to a part of the radius "R"of the rotatable disc 3.

The gas conducting surfaces 32n are adapted, via edge lines 32na, for heat conducting co-action with said pipes within an area situated within a bound- ary region between adjacent pipes.

The cooled waste gas is conducted, via the connection 32f, between said three parallel surfaces, and the surfaces are surrounded by a casing 32a of part- torus shape.

The waste gases are caused to pass in said casing in a direction opposite to the chosen direction in which said fluid flows through said pipe sections.

The helical gas conducting flanges and their respective surfaces are cho- sen in number from between two (2) and five (5) parallel-related continuously heli- cal wall sections.

The helical fluid conducting pipes are chosen in number from between two (2) and five (5) parallel-related continuous helical pipe sections.

The casing 32a has along the peripheral surface region of the disc 3 an extension corresponding to an angle of between 110 and 140°, preferably about 130°.

The casing 32a has a diameter (D1), which has values lying between 5/45 and 10/45, such as about 6/45 in relation to a disc diameter (D2 = 2R).

It will be understood that the invention is not restricted to the afore de- scribed and illustrated exemplifying embodiment thereof and that modifications can be made within the scope of the inventive concept as illustrated in the accom- panying claims.