Method for producing pressing plates for irons, and plates obtained using this method

Description

[0001] It is known that industrial-type steam irons are fed with steam supplied from an external source by means of a pipe to the pressing plate.

[0002] The plate is so shaped internally as to prevent water droplets, which inevitably form as the result of part of the steam condensing in the pipe leading from the supply to the plate, from reaching the fabric and interfering with perfect ironing.

[0003] The steam is thus made to flow through a succession of adjacent vertical traps inside the plate, into which the water droplets present in the steam fall and are caught, later returning to a gaseous state as a result of the heat given off by the pressing plate.

[0004] The steam is finally conveyed to a chamber inside the plate, featuring holes in its bottom surface that are arrayed in a "V" shape, with the point directed towards the apex of the latter, and through which the steam flows out, moistening the fabric.

[0005] Plates of this type are produced using a process known as chill casting, and the spaces inside the plate, namely the traps and chamber, are obtained using suitably shaped cores held in place by supports.

[0006] These cores are made of a material which can, once the plate has hardened, easily be smashed and pulverised using known processes, (for example, by subsequently reheating them), and then removed from within the plate through the holes left along the border of the latter by the supports.

[0007] Production of the plate as described above involves certain problems.

[0008] In the first place, chill casting gives the plate a porous surface which must therefore undergo finishing in subsequent stages of the process.

[0009] Furthermore, the production of a high number of traps, as is necessary for optimum plate operation, requires the use of a high number of cores and, consequently, of supports.

[0010] Since the supports inevitably leave holes that bring the internal ducts into communication with the outside environment, these must later be closed off, this subsequently involving long operations, the results of which are not always satisfactory, above all as a result of the materials normally used in the production of the plates.

[0011] The zones occupied by those holes remain easily visible, however, detracting from the aesthetic appeal of the product.

[0012] It should finally be emphasised that the chill casting process gives rise to a high number of imperfect products, that must thus be scrapped later on, and is furthermore characterised by notably complex operations, such as, for example, the preparation of the chills, which can only be used for a limited number of castings. The above-mentioned drawbacks have a negative effect on the overall cost of the article.

[0013] The use of "die-casting" for the production of plates shaped as described above, has also shown itself to be difficult and unsuitable, producing unsatisfactory results regarding both the traps and chamber.

[0014] In particular, it is necessary to make a long slit along the edges of the apex in order to extract the core from the plate, this detracting from the aesthetic appeal of the product, and also resulting in poor chamber sealing.

[0015] From the document US-A-2 431 545 it is known a pressing plate having a plurality of connecting bores, which are provided with steam by an inlet connection.

[0016] A first bore is connected with the inlet connection and with an enlarged second bore through a third transverse bore.

[0017] The second and third bores are closed by means of screw plugs.

[0018] A cross fourth bore connects the second enlarged bore with a fifth longitudinal enlarged bore which in turn is connected with a sixth enlarged bore by a seventh cross bore.

[0019] The sixth bore is lastly connected with two consecutive inclined bores which crosses each other in the fore part of the plate.

[0020] All bores fourth, fifth, sixth, seventh and the inclined ones, are closed by means of screw plugs.

[0021] The inclined bores have series of ports through the bottom of the plate so that the steam may discharge onto the work material being pressed.

[0022] Helically grooved heat conductive members are placed into the enlarged bores to re-vaporize supersaturate steam.

[0023] An electric heating element is disposed in a horse-shoe shape and arranged in heating relation to the plate.

[0024] The object of the present invention is to propose a method enabling pressing plates to be produced with increased productivity, in terms of number of plates per unit of time, than has until now been effected, giving rise to a lower number of scrap pieces, and, in addition, obtaining qualitatively superior results.

[0025] The aforesaid objects are achieved by means of a method for producing steam iron pressing plates, designed to be supplied with steam fed from an external source, with each plate featuring an internal pathway for conveying the steam itself to a plurality of outlet holes produced in the base of said plate; the said method being characterised by the fact that it includes: the production by die-casting of a plate featuring a plurality of blind ducts, respectively first, second and third, that run alongside one another, originating in the rear edge of the said plate, as well as further ducts, respectively fourth and fifth, each originating in one side of the apex of the plate itself, the fourth joining the inside end of the said third duct, and the fifth being incident to the fourth and joining it at an intermediate point; the production, by drilling, of further ducts, respectively sixth and seventh, for connecting, respectively, the first and second, and second and third of the said ducts; the extension, by drilling, of the said fifth duct, for a predetermined portion, extending beyond the said fourth duct; the production of a plurality of holes in the base of the said plate, corresponding with the said fourth duct and aforementioned extended portion; the closure of the outside ends, along the edges of the said plate, corresponding to the said second, third, fourth, fifth, sixth and seventh ducts.

[0026] The characteristics of the invention, that do not emerge from that described above, are emphasised hereinafter with specific reference to the accompanying drawings, in which:

• figures 1 and 2 illustrate a completed plate, produced as in the method that is the subject of the present invention, as seen from above and from behind respectively;
• figures 3 and 4 illustrate the same plate as seen, respectively, in cross section at lines I-I and II-II in figures 1 and 2.
• figure 5 illustrates a plate in an intermediate stage of the process as seen in cross section at line II-II in fig. 2.

[0027] With reference to the aforesaid figures, 10 shows a pressing plate for a steam iron designed to be supplied with steam fed from an external source.

[0028] The plate is made by die-casting as in the method that is the subject of the present invention.

[0029] The tubular ducts are produced during this process by means of suitably placed metal cores.

[0030] As shown in fig. 5, three ducts 11, 12 and 13, respectively first, second and third, running side by side and originating in the rear edge of the plate, extend a predetermined length within the plate, and are closed at the ends opposite the rear edge of the plate. Two further ducts, 14 and 15, respectively fourth and fifth, originate at the two side edges of the apex of the plate, close to its tip.

[0031] The fourth duct 14 joins the inside end of the third duct 13, whilst the fifth duct 15, incident to the fourth, joins it laterally at an intermediate point.

[0032] An electric heating element 19, for heating the plate, is placed above the second and third ducts, and above part of the the fourth duct, during the process, and held in place by means of suitable supports, not illustrated, remaining enclosed within a corresponding channel 18, as shown in fig. 1.

[0033] Two further ducts 16 and 17, sixth and seventh respectively, perpendicular to ducts 11, 12 and 13, are subsequently produced by drilling.

[0034] The sixth duct 16, originating at the side edge of the plate nearest to the first duct 11, and corresponding with its inside end, serves to connect the latter with the inside end of the second duct 12.

[0035] The seventh duct 17, originating at the opposite side edge of the plate, corresponding with the outer end of the third duct 13, serves to connect the latter to the outer end of the second duct 12.

[0036] The fifth duct 15 is extended by drilling a portion 15b, extending beyond the fourth duct 14, below a part of channel 18.

[0037] A pathway is thus created, consisting of, in order, the first duct 11, the sixth duct 16, the second duct 12, the seventh duct 17, the third duct 13, the fourth duct 14 and the extended portion 15b.

[0038] Equidistant holes 20 are made corresponding with the latter two ducts, forming a "V" shape with the point directed towards the apex of the plate.

[0039] The holes located along the edges of the plate, corresponding to ducts 14, 15, 16 and 17, in other words the fourth, fifth, sixth and seventh ducts, are closed off using known processes, and the initial portions of the three ducts 11, 12 and 13 are threaded.

[0040] The plate then undergoes subsequent finishing processes. During assembly of the steam iron, three filter elements 22, made of heat-resistant material, are inserted in the three ducts 11, 12 and 13, serving to collect the water droplets suspended in the steam, which are then returned to a gaseous state as a result of the heat given off by the plate.

[0041] The second and third ducts are then closed by means of screw-in plugs 21, whilst the first duct is connected to the steam supply pipe.

[0042] The method that is the subject of the present invention for producing pressing plates has obvious advantages. In the first place, the use of die-casting instead of "chill casting" enables higher quality plates to be produced more quickly, with a lower number of scrapped products, without necessitating additional operations for removing the cores.

[0043] The use of this process is made possible by the special design of the ducts, which is in turn made practicable by the use of filter elements, replacing the traps in the version referred to in the introduction.

[0044] The replacement of the chamber, present in the models produced as decribed in the introduction, with duct 14 and extended portion 15b, forming a "V" shape, is a further decisive factor in achieving the goal of being able to produce the plate using die-casting.

[0045] Furthermore, the increase in quality obtained using this process, reduces the finishing processes subsequently undergone by the plate.

[0046] The possibility of enclosing the plate heating element during the casting stage represents a considerable advantage in terms of time saving during the steam iron assembly stage.

[0047] Finally, the layout of the ducts within the plate makes it easy for the drilling stages to be automated, with the obvious consequent advantages.

Claims

1. Method for producing steam iron pressing plates, designed to be supplied with steam fed from an external source, with each plate (1) featuring an internal pathway for conveying the steam itself to a plurality of outlet holes (20) produced in the base of the said plate; the said method being characterised by the fact that it includes: the production by die-casting of a plate (1) featuring a plurality of blind ducts (11, 12, 13), respectively first, second and third, that run alongside one another, originating in the rear edge of the said plate, as well as further ducts (14, 15), respectively fourth and fifth, each originating in one side of the apex of the plate (1) itself, the fourth joining the inside end of the said third duct (13), and the fifth being incident to the fourth and joining it at an intermediate point; the production, by drilling, of further ducts (16, 17), respectively sixth and seventh, for connecting, respectively, the first (11) and second (12), and second (12) and third (13) of the said ducts; the extension, by drilling, of the said fifth duct, for a predetermined portion (15b), extending beyond the said fourth duct (14); the production of a plurality of holes in the base of the said plate, corresponding with the said fourth duct (14) and aforementioned extended portion (15b); the closure of the outside ends, along the edges of the said plate, corresponding to the said second (12), third (13), fourth (14), fifth (15), sixth (16) and seventh (17) ducts.

2. Method, as in claim 1, for producing steam iron pressing plates, each plate being fitted with an electric heating element (19), characterised by the fact that the stage in which the said plate (10) is produced by die-casting includes the production of a channel (18) located above the said first (11), second (12), third (13) and fourth (14) ducts, and above the aforementioned extended portion (15b), within which the above-mentioned electric heating element (19) is enclosed at the same time.

3. Method as in claim 1, characterised by the fact that it includes the threading of the initial portion of the said first duct (11).

4. Method as in claim 1, characterised by the fact that it includes the insertion of filter elements, serving to collect water droplets suspended in the steam, in the said first (11), second (12) and third (13) ducts, before the above-mentioned closure of the ducts.

5. Method as in Claim 1, characterised in that it includes making a channel (18) above said conducts, within which an electric heating element (19) is enclosed.

Revendications

1. Procédé pour la production de plaques de pression de fers à vapeur, destinés à recevoir la vapeur d'une source extérieure, avec chaque plaque (10) formant un passage à l'intérieur pour l'acheminement de la vapeur vers une série de trous débouchants (20) percés dans la base de ladite plaque; ledit procédé étant caractérisé en ce qu'il comprend: la production, par moulage sous pression, d'une plaque (10) contenant plusieurs conduits aveugles (11, 12, 13), respectivement appelés premier, deuxième et troisième conduits, situés l'un à côté de l'autre et partant de l'arrière de ladite plaque, ainsi que d'autres conduits (14, 15), respectivement appelés quatrième et cinquième conduits, partant chacun d'un côté du sommet de ladite plaque (10), le quatrième étant relié à l'extrémité intérieure dudit troisième conduit (13) et le cinquième étant relié au quatrième en un point intermédiaire; la production, par perçage, d'autres conduits (16, 17), respectivement appelés sixième et septième conduits, pour relier, respectivement, le premier (11) et le deuxième (12), ainsi que le deuxième (12) et le troisième (13) desdits conduits; l'extension, par perçage, dudit cinquième conduit, sur un tronçon prédéterminé (15b), allant au delà dudit quatrième conduit (14); la production d'une série de trous dans la base de ladite plaque, au niveau dudit quatrième conduit (14) et dudit tronçon (15b); la fermeture des extrémités extérieures, le long des bords de ladite plaque, au niveau desdits deuxième (12), troisième (13), quatrième (14), cinquième (15), sixième (16) et septième (17) conduits.

2. Procédé selon la revendication 1, pour la production de plaques de pression de fers à vapeur, chaque plaque étant dotée d'un élément électrique de chauffage (19), caractérisé en ce que le stade de production de ladite plaque (10), par moulage sous pression, comporte la production d'un canal (18) situé au-dessus desdits premier (11), deuxième (12), troisième (13) et quatrième (14) conduits, et au-dessus du tronçon d'extension (15b), à l'intérieur duquel est placé ledit élément électrique de chauffage (19).

3. Procédé selon la revendication 1, caractérisé en ce qu'il comprend le filetage d'une portion initiale dudit premier conduit (11).

4. Procédé selon la revendication 1, caractérisé en ce qu'il comprend l'introduction d'éléments de filtrage, servant à recueillir les gouttes d'eau en suspension dans la vapeur, à l'intérieur desdits premier (11), deuxième (12) et troisième (13) conduits, avant la fermeture des conduits.

5. Procédé selon la revendication 1, caractérisé en ce qu'il comprend la réalisation d'un canal (18) au-dessus desdits conduits et à l'intérieur duquel est introduit un élément électrique de chauffage (19).

Ansprüche

1. Verfahren zur Herstellung von Dampfbügeleisenplatten, ausgelegt für die Dampfversorgung aus einer externen Quelle, wobei jede Platte (10) eine innere Bahn für die Dampfzufuhr zu mehreren Auslaßöffnungen (20) aufweist, welche an er Unterseite der genannten Platte vorgesehen sind; genanntes Verfahren ist dadurch gekennzeichnet, daß es folgendes umfaßt: die Herstellung durch Druckgießen einer Platte (10), welche mehrere Blindleitungen (11, 12, 13), jeweils die erste, zweite und dritte Leitung, aufweist, welche ausgehend vom hinteren Rand der genannten Platte nebeneinander verlaufen, sowie weitere Leitungen (14, 15), jeweils die vierte und die fünfte, welche jeweils von einer Seite der Spitze der Platte (10) ausgehen, wobei die vierte in das innere Ende der genannten dritten Leitung (13) übergeht und die fünfte winkelig zur vierten angeordnet ist und in mittlerer Stellung in diese übergeht; die Herstellung durch Bohren von weiteren Leitungen (16, 17), jeweils die sechste und die siebente, zur Verbindung zwischen der ersten (11) und der zweiten (12) sowie zwischen der zweiten (12) und der dritten (13) der genannten Leitungen; die Verlängerung durch Bohren der genannten fünften Leitung über einen bestimmen Abschnitt (15b), der über die genannte vierte Leitung (14) hinausgeht; die Herstellung von mehreren Bohrungen im Unterteil der genannten Platte in Übereinstimmung mit der genannten vierten Leitung (14) und dem vorgenannten verlängerten Abschnitt (15b); das Verschließen der äußeren Enden längs der Ränder der genannten Platte entsprechend der genannten zweiten (12), dritten (13), vierten (14), fünften (15), sechsten (16) und siebenten (17) Leitung.

2. Verfahren gemäß Anspruch 1 zur Herstellung von Dampfbügeleisenplatten, wobei jede Platte mit einem elektrischen Heizelement (19) ausgestattet ist, dadurch gekennzeichnet, daß bei der Herstellung durch Druckgießen der genannten Platte (10) gleichzeitig ein Kanal (18) angefertigt wird, der über genannter ersten (11), zweiten (12), dritten (13) und vierten (14) Leitung, und dem genannten verlängerten Abschnitt (15b) angeordnet ist, in dem gleichzeitig das genannte elektrische Heizelement (19) aufgenommen ist.

3. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, daß es die Herstellung eines Gewindes im anfänglichen Teil der genannten ersten Leitung (11) umfaßt.

4. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, daß es das Einsetzen von Filterelementen zum Auffangen der im Dampf enthaltenen Wassertröpfchen, in genannter ersten (11), zweiten (12) und dritten (13) Leitung vor dem genannten Verschließen der Leitungen umfaßt.

5. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, daß es die Herstellung eines Kanals (18) über genannten Leitungen umfaßt, in dem ein Heizelement (19) untergebracht ist.

Drawing