US2577584A

US2577584A - Manufacture of meshlike ornamental articles

Info

Publication number: US2577584A
Application number: US9426A
Authority: US
Inventors: Hofreiter Alois
Original assignee: Tyrolit-Schleifmittelwerke Swarovski KG
Current assignee: Tyrolit-Schleifmittelwerke Swarovski KG
Priority date: 1946-08-12
Filing date: 1948-02-19
Publication date: 1951-12-04
Anticipated expiration: 1968-12-04

Description

Dec. 4, 1951 HQFREITER 2,577,584

MANUFACTURE OF MESH-LIKE ORNAMENTAL ARTICLES Filed Feb. 19, 1948 0v mew roe.-

ALO/S HOF E/TER BY ATTORNEY.

Patented Dec. 4, 1951 MANUFACTURE OF MESHLIKE ORNA- MENTAL ARTICLES Alois Hofreiter, Wattens, Tirol, Austria, assignor to D. Swarovski Glasfabrik und Tyrolit Schleifmittel-Werke, Wattens, Tirol, Austria,

Application February 19, 1948, Serial No. 9,42ii

v In Austria August 12, 1946 Section 1, Public Law 690, August 8,- 1946 Patent expires August 12, 1966 7 Claims. (01. 1836) Hitherto ribbons comprising decorative elements arranged on crossed connecting means such as threads or wires, which are embedded in the elements during the moulding of the same, have been produced in such a way that the two crossed sets of connecting means have been inserted into grooves provided in the, surface of the lower part of the mould, where they have been secured during the moulding operation. (See Austrian Patent No. 131,193, Figs. 7-10.) In order to prevent flowing of the material of which the elements are cast, out of the cavities for moulding and into the grooves, the latter are made so small that they are just able to receive the threads or wires. The tensioned longitudinal and transversal threads are substantially in the same plane but are bent thereout at their crossing points whereby the upper thread is lifted out of the groove at the margin of the mould and loose their hold therein. Therefore the upper threads are liable to be caught between the surfaces of the two parts of the mould when the upper part of the same is applied, thus preventing the mould from being completely closed whereby the elements are undesirably enlarged and thin plates are produced between the molds which plates envelope the free portions of the threads. Obviating of such defects is either not possible at all, or at least difiicult and uneconomic, and unobjectionable appearance is scarcely attainable. The portions of the threads between the elements, if enveloped in the material are no longer suii'lciently yieldable, and stiffen the ribbon.

One may think of making the grooves deeper for receiving the first inserted threads running in the same direction. However, in such a case, it would be necessary to provide small ribs at the upper part of the mould which ribs close those portions of the grooves which are not filled up with the threads, thus preventing the molding material from entering the said cavities. In this way the product would be improved in principle but difificulties arise in connection with the sealing of the mould, since it is not possible in such a case to bring the adjacent surfaces of the two parts of the mould in close contact with one another by simply grinding them at one another. The necessary hardening of the elements by heating also changes the contact surfaces of the molds and would necessitate a troublesome finishing of the surfaces latticed in such a way. Manufacture of the moulds and keeping them in good repair would be too expensive.

The invention relates to ribbons or the like .of elements into which the connecting means are embedded during the moulding of the elements as well as to a process of and an apparatus for producing the same, an object of the invention being obviating the aforementioned drawbacks.

This object is attained according to the invention by arranging the two sets of parallel connecting means adjacent and in two planes, one above another. A plane imagined through the joint separating the two parts of the mould coincides with the plane where the two sets of connecting means come in contact and with the plane from which taper in opposite directions the upperand, lower portions of the decorative elements. Thereby the ribbons according to the in vention differ from conventional ones at the first glance, as in case of conventional products said plane is situated outside the two sets of connecting means, where it becomes distinctly-visible, whereas it is less visible in the objects according to the invention.

According to the invention the ribbons are manufactured in such a way, that one of the two sets of parallel connecting means is secured in the grooves of the lower part of the mould during the moulding of the elements,- whereas the other set is secured in the grooves of the upper part. According to a modified embodiment of the invention thethreads, especially the transversal ones to be inserted into the grooves of the upper part, may be connected by a preparatory operation, and embedded in moulded and parallel bars which are preferably placed in the upper part of the mold. The finished bands are cut into individual pieces by cutting through the wires or the like adjacent the bars. Tensioning of the threads or wires is effected by forcing the bars into corresponding cavities of the mould. In case only short pieces of ribbons are to be produced the described operation may as well be used in connection with the longitudinal threads which are secured by bars in grooves of the lower part of the mould.

An embodiment of the invention is represented by way of example in the drawing.

Fig. 1 is a sectional view of a ribbon, the elements made of moulded material of which form at the same time mountings of jewels,

, Fig. 2 is a sectional view of a mould for spraycasting, showing the inserted connecting means,

Figs. 3 and 4 are perspective partial views of the lower part and the upper part of the mould respectively, the surfaces of contact of the two parts being visible,

3 Figs. 5 and 6 are similar views of the two parts of the mould, showing the longitudinal threads and the transversal ones inserted,

Fig. '7 illustrates a band of threads held in position by means of bars moulded in a preparatory I operation.

Elements I (Fig. 1) have been moulded into mountings of jewels 2 and overlap them slightly at the edges in the neighborhood of the greatest diameter of the jewel. The two sets of the crossed connecting means 3, 4 composed of threads or wires, are disposed in two adjacent planes in such a way, that they just touch without displacing one another. The plane dividing the moulded parts into portions 1' and I" is situated between the two sets of threads or string means 3 and 4 as is seen in the drawing. Although it is advantageous to dimension the portion I with a-smaller diameter, it is not essential and is not a substantial feature of the invention.

The mould (Fig. 2') is composed of the lower part l2 and the upper part 6. The cavities corresponding'to the portions I, I"' of the moulded elements which are shaped in the present case into semi-pearls and are not provided with jewels, are denominated l and 10". The threads 3 are placed into grooves 1 of the upper part 6, and the threads 4 into grooves l3 of the lower part l2. The two sets of threads arekept under tension, which may be effected according to the invention by

moulding bars

8, 8", 3 by pairs in equal distances on tensioned parallel threads, for instance the threads .3 (Fig. 3). by a preparatory operation, which bars join the threads into a band. For inserting the threads joined in the described way into the respective part of the mould, the threads are cut through. at I9 between the bars'8, 8", and. so on. The .bars'8', 8" bordering a section of the band are forced into cavities 9 of the part .6 .of the mould, the distance of the cavities being such as to subject the threads to a tension. H are channels .for' supplying the moulding material.

As seen in Figs. 3' and 4 the grooves I and I 3 have the same depth. The depth and width of the grooves are such as to tightly surround the threads not leaving any space through which moulding material may enter.

As seen from the Figs. 5 and, 6 the threads "'4' are the longitu'dinal'threads of the ribbon tobe produced, whereas the threads 3 form the transversal threads. Feeding on of the longitudinal threads is done from the right of the lower part of Fig. 5 to the left of the upper-part. The piece of the ribbon produced in the previous moulding operation and provided with moulded parts I4 is already outside of the mould, but its last row [5 is inserted in cavities of the lower part t2 of the mould, to which cavities no liquid moulding material is supplied as they are provided only 'for support forenabling the threads 4 to be tensioned at the feeding side, which may be effected in the known manner by applying springs, for 'in-, stance on the bobbins from which the threads run off. The surfaceof the upper part 6 of the mould (Fig. 6) is provided with a row of cavities l5 adapted .to receive portions of the momentarily final row l5, projecting from the lower part of the mould. The transversal threads 3 are inserted by forcing the bars 8 of the prepared threadband (Fig. 7) into the grooves of the upper part of the mould whereby the mould is made ready to be closed for carrying out the next moulding operation. The top part I6 is adapted for supplyin the moulding material to the injection channels or in-gates II. The parts of the mould are immovably secured to one another in the usual way by pins l1 and bores IS.

The moulded bars 8 are already removed from the finished piece of ribbon represented in Fig. 5.

Instead of moulding the bars by pairs in a preparatory operation, there may be provided a single bar which is moulded in the groove 9 at the feeding side of the transversal threads, provided one has taken care in another way that the threads are tensioned when the moulded bar is inserted into the other groove 9 after the transversal threads have been advanced. On the other hand, finished pieces of thread-bands according to Fig. 7 may be used in the lower part of the mould.

In other respects the ribbons are produced by conventional methods. After injecting the moulding material, effecting at the same time moulding of the decorative elements and embedding the threads and, if desired, the jewels or the like too, the mould is opened, the upper part of the mould is removed, and the finished ribbon is lifted out of the mould after the burrs have been removed, whereupon, if desired, after supplying the cavities of the lower part of the mould again with jewels, the ribbon is advanced as far as to enable the final row IE to be forced into the cavities [5, the threads running off the spring retarded bobbins in a tensioned state. Finally, the bars 8 01 the pieces of threads-band are forced into the grooves 9, whereupon the mould is closed for the next moulding operation.

The threads need not be provided by pairs. The number and the arrangementof the threads with regard to one another as well as the angle of crossing may be chosen at will. The threads of-the two sets may also be arranged in parallel, offering an advantage in view of a certain manner of fixing the ribbon.

In addition to obviating the aforesaid drawbacks, the invention oifers the advantage that the mould for producing the ribbons is a very simple one, permanent sealing of the parts of the mould is attainable by simple means, and the appearance of the ribbon is improved by placing the plane where the upper portion of the moulded elements meets the lower portion to coincide with the plane between the two sets of connectingmeans. v

The ribbons according to the invention are excellently suitable for mass production. Hitherto production of jewelry ribbons with crossed connecting means suffered from diillculties in manu facture. However compared with ribbons showing only longitudinal threads and staggered moulded parts alternatively connecting two neighbouring threads, the ribbons with crossed threads offer the special advantage that they, in the same way as fabrics, are not extensible in the longitudinal and the transversal direction resulting in increased applicability.

What I claim is:

1. The method of producing ribbons composed of a plurality of molded decorative elements, each element having 'a face portion and a rear portion and a portion of maximum cross-section disposed therebetween, and two groupsv of string means placed in parallel planes and extending through said elements near their maximum crosssections; which method comprises setting one group of string means in a plane in a half-mold in transverse relation to cavities corresponding to' the face portions of the elements and having their maximum cross-section adjacent to said plane,

5, setting another group of string means independently of the first group in a plane in a half-mold complementing the first half-mold and in transverse relation to cavities'corresponding to the rear portion of the elements, placing 'said-ha1fmolds adjacent to one another to close the cavities and to place the planes in which the two groups of string means are located parallel to one another, and filling the cavities with a molten material.

2. The method of producing ribbons composed of a plurality of molded decorative'elements, each element having a portion of maximum cross section, and two groups of string means extending through said elements at their maximum cross section and in two parallel planes, which-method comprises setting a group of string means in a plane in a mold in transverse relation to cavities having their maximum cross section parallel to and adjacent said plane, setting another group of string means within the mold independently of and substantially transversely to the string means of the first group and in a plane parallel to the plane of the first group and also adjacent the maximum cross section of the cavities, and pouring a molten material into the mold while tensioning individually the groups of string means.

3. The method of producing ribbons composed of a plurality of molded decorative elements, each element having a portion of maximum cross section, and two groups of parallel string means extending through said elements at their maximum cross section and in two parallel planes, which method comprises embedding the ends of the string means of one group in bars extending crosswise to the string means, setting the group of string means with the-bars in a plane in a mold in transverse relation to cavities having their maximum cross section parallel to and adjacent said plane, setting a group of continuous string means within the mold independently of and substantially transversely to the string means of the first group and in a plane parallel to the plane of the first group and also adjacent the maximum cross section of the cavities, pouring a molten material into the mold, and severing the bars from the string means after the material has hardened.

4. The method of producing ribbons composed of a plurality of molded decorative elements, each element having a portion of maximum cross section and two groups of parallel string means extending through said elements at their maximum cross section and in two parallel planes, which method comprises embedding the ends of the string means of one group in bars extending crosswise to the string means, tensioning the string means of said group across the maximum cross section of cavities in a mold by pressing the bars in corresponding grooves in the mold, setting another group of string means within the mold independently of the first group and in a plane parallel to the first group and adjacent the maximum cross section of the cavities, pouring a molten material into the mold, and severing the bars from the string means after the material has hardened.

5. A mold for producing ribbons composed of a plurality of molded decorative elements, each element having a portion of maximum cross section, and two groups of string means extending through said elements at their maximum cross section and in two parallel planes, the string means of one group extending substantially transversely to those of the other group; saidmold comprising an upper part and a lower part, said upper part having a plurality of rows of cavities negatively conforming with the portion of the elements above their maximum cross section, an in-gate for each cavity, and having grooves for receiving the string means of one group; said lowerpart having a plurality of rows'of cavities negatively conforming with the portion of the elements below their maximum cross section, and grooves extending substantially transversely to and in a plane different from the plane of the grooves in the upper part of the mold, for receiving the string means of the other group.

6. A mold for producing ribbons composed of a plurality of molded decorative elements, each element having a portion of maximum cross section, and two groups of string means extending through said elements at their maximum cross section and in different parallel planes, the string means of one group extending substantially transversely to those of the other group, the string means of one group being short and having their ends embedded in bars for facilitating setting the group in the mold which bars are severed when the ribbon is completed, and the string means of the other group being continuous; said mold comprising an upper and a lower part, the upper part having a plurality of rows of cavities negatively conforming with the portion of the elements above their maximum cross section, an in-gate for each cavity, and having grooves receiving the string means of one group; said lower part having a plurality of cavities negatively conforming with the portion of the elements below their maximum cross section, and grooves extending substantially transversely to and in a plane different from the plane of the grooves in the upper part of the mold, for receiving the string means of the other group; and additional grooves in one of said parts conforming with and receiving said bars.

7. The method of producing a ribbon composed of a plurality of molded decorative elements, each element having a portion of maximum cross-section, and two groups of parallel string means placed individually in parallel planes and extending through the portion of maximum cross-section of said elements, the string means of one group being relatively short and disposed transversely and adjacent to those of the other group which are continuous; said method comprising connecting the ends of a group of parallel string means to a bar extending across said ends, molding a second bar to said string means at a distance from the first bar corresponding substantially to the width of the ribbon, molding a third bar to said string means parallel to and at a distance from the second bar for permitting cutting of the string means between the second and third bar, molding a fourth bar to the string means at a distance from the third bar corresponding substantially to the width of the ribbon, molding a fifth bar in the same close relation to the fourth bar as the second and third bars and so forth for preparing a continuous band of prefabricated groups of parallel string means, severing the string means between the second and third bars, between the fourth and fifth bars, andso forth for producing a supply of elements having parallel string means of a length corresponding substantially to the width of the finished ribbon, secured between bars; setting a prefabricated element in a.mold with the string means transverse to cavities corresponding in shape to that of the decorative elements, setting another group of continuous parallel string means transversely to the cavities in the mold with the'string means of the other group transverse and adjacent to those of the prefabricated element, tensioning the string means of the other group, pouring a molten material into the cavities of themold, severing the bars from the string means of the prefabricated element after the material has hardened and taking the so produced portion of the ribbon out of the mold, placing a second prefabricated element in the mold, advancing the string means of the other group and placing same transversely to the cavities in the mold and transversely and adjacent to the string means of the prefabricated elements, pouring a molten material into the cavities of the mold while the string means of the'other group are held under tension, severing ALOIS HOFREITER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 215,231 Manly May 13, 1879 2,163,814 Swarovski June 27, 1939 2,253,659 Swarovski Aug. 26, 1941 2,276,380 English Mar. 17, 1942