Method for manufacturing a hollow glass item

10822263 ยท 2020-11-03

Assignee

Inventors

Cpc classification

International classification

Abstract

The present disclosure relates to a method for manufacturing a hollow glass item and, specifically, to a method for manufacturing an item made of hollow pressed glass. The method includes a step of depositing at least one drop of molten glass into a mold intended for modelling a predetermined outer shape of the glass item to be manufactured; a step of pressing the molten glass into the mold by a shaping punch in order to shape the hollow glass item by hollowing out an inside space; a step of marking the glass item with a marking tool which is independent from the shaping punch, in order to imprint at least one raised and/or recessed pattern in the inside space of the glass item; a step of cooling the marked, pressed glass item; and a step of removing the glass item from the mold.

Claims

1. A manufacturing process of at least one item made of pressed hollow glass, the manufacturing process consisting of: depositing at least one drop of molten glass into a mold configured to model a predetermined outer shape of the at least one hollow glass item; pressing the at least one drop of molten glass against the mold by a forming punch such that an inner volume of the at least one hollow glass item is hollowed out and forms a final overall shape; marking the at least one hollow glass item by a marking tool independent of the forming punch and operable to print at least one of a relief pattern and a recessed pattern on an inner surface of the at least one hollow glass item; cooling the at least one hollow glass item; and demolding the at least one hollow glass item.

2. The manufacturing process according to claim 1, wherein the marking step is implemented when a temperature of the glass is between 725 and 775 degrees Celsius.

3. The manufacturing process according to claim 2, wherein the temperature of the glass is about 750 degrees Celsius.

4. The manufacturing process according to claim 1, wherein a marking time of the marking step is less than 0.6 seconds.

5. The manufacturing process according to claim 1, wherein a marking time of the marking step is less than 0.5 seconds.

6. The manufacturing process according to claim 1, wherein the at least one hollow glass item, after pressing, has a thickness greater than 1 mm.

7. The manufacturing process according to claim 1, wherein the at least one hollow glass item, after pressing, has a thickness greater than 2 mm.

8. The manufacturing process according to claim 1 further comprising burning the at least one hollow glass item by burners after the demolding step.

9. The manufacturing process according to claim 1, wherein a plurality of glass items are being manufactured and the pressing step and the marking step are implemented simultaneously for distinct glass items.

10. The manufacturing process according to claim 9, wherein a marking time of the marking step is less than a pressing time of the pressing step.

11. An equipment for manufacturing at least one glass item, the equipment comprising: a mold for modeling a predetermined outer shape of the at least one glass item; a forming punch; a marking tool independent of the forming punch; and a demolding tool, wherein the equipment is capable of manufacturing a plurality of hollow glass items according to the manufacturing process of claim 1.

Description

DRAWINGS

(1) In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

(2) FIGS. 1A, 1B, 1C, 1D, 1E, 1F, and 1G, illustrate schematic views of different steps of a manufacturing process of a pressed and customized glass item according to the present disclosure;

(3) FIGS. 2A and 2B, are sectional views of a hollow glass item and a portion of a marking tool during two different phases of a marking step according to one form of the present disclosure;

(4) FIG. 3 is a top view of the hollow glass item and the marking tool of FIGS. 2A and 2B during the marking step;

(5) FIGS. 4A and 4B are sectional views of a hollow glass item and a marking tool during two different phases of a marking step according to another form of the present disclosure;

(6) FIG. 5 is a perspective view of the marking tool of FIGS. 4A and 4B;

(7) FIG. 6 is a perspective view of a customized pad of a marking tool according to one form of the present disclosure; and

(8) FIG. 7 is a perspective view of a customized glass item according to the present disclosure.

(9) The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

(10) The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

(11) In a first deposition step illustrated in FIG. 1A, a precisely calibrated drop 3 of molten glass 2 is deposited into a mold 4 as illustrated by the arrow F1. The mold 4 is intended to model a predetermined outer shape of the glass item 1 to be manufactured.

(12) The glass drop 3, also called gob has a specific mass, namely that of the final item 1 to be manufactured.

(13) Once the drop 3 of molten glass 2 is deposited in the mold 4, said mold 4 is displaced under a forming punch 5 (see FIG. 1B) before the implementation of a pressing step (see FIG. 1C) in which the molten glass 2 deposited beforehand in the mold 4 is then pressed by the forming punch 5.

(14) The pressing of the molten glass 2 against the mold 4 is obtained by the forming punch 5 which is lowered by translating vertically towards the mold 4 as illustrated by the arrow F2 and which penetrates an inner space of the mold 4 in order to confer the shape to the hollow glass item 1 by hollowing an inner volume 6 out. Indeed, an inner wall of the mold 4 allows defining an outer envelope to the glass item 1 to be manufactured and an outer wall to said forming punch 5 allows defining an inner envelope, complementary to the outer envelope of the mold 4, of the Item 1 to be manufactured. In this way, this pressing step allows conferring to the glass item 1 its final and hollow overall shape.

(15) In one aspect, the mold 4 and the forming punch 5 are configured so that the glass item 1, after pressing, has a thickness greater than 1 mm and in one form has a thickness greater than 2 mm.

(16) Subsequently to this pressing step, the glass item 1 is displaced to another manufacturing station then customized during a marking step 7 by a marking tool independent of the forming punch 5 (see FIG. 1D).

(17) During this step, the marking tool penetrates at least partially the inner volume 6 of the glass item 1 and prints a relief and/or recessed pattern 8 against an inner surface of a wall of said glass item 1, being understood that the inner surface of the glass item is a surface of the wall of the item 1 facing the side of the inner volume 6. The marking step is illustrated in detail in FIGS. 2A, 2B, 3 and 4A, 4B, and 5.

(18) More specifically, the marking tool 7 comprises at least one arm 70 at the end of which is positioned a customized pad 80, this pad 80 being removable relative to said arm 70. An example of such a customized pad 80 is illustrated in FIG. 6.

(19) In each of the various forms illustrated in FIGS. 2A, 2B, 3, 4A, 4B and 5, it will be noted that the marking tool has two arms 70, in particular here arranged so as to be each capable of marking the glass of a pattern 8 and that both patterns 8 are opposite relative to each other with respect to a vertical axis of rotation X of the glass item 1 which has a rotational symmetry.

(20) During this marking step, and generally, the marking tool 7 brings the pad(s) 80 in contact and in abutment against an inner surface of a wall of the glass item 1, such as a lateral wall 11 of the glass item 1, as illustrated particularly in FIGS. 2B and 4B.

(21) In one form, the marking tool 7 is configured so that the contact is simultaneous at any point of the pattern 8 so as to improve the quality of its printing. More specifically here, the marking tool 7 performs, on the one hand, a substantially vertical movement to enter (arrow F3) the distal end 72 of each arm 70 carrying a pad 80 in the inner volume 6 of the glass item 1 as illustrated in particular in FIGS. 2A and 4A, and on the other hand, in successively and/or at least partly concomitantly, a substantially horizontal movement (F4) or substantially radial with respect to the glass item, to mark the item 1.

(22) Once the glass is marked, that is to say once the pad 80 printed the relief and/or recessed pattern 8 in the inner volume 6 of the glass item 1 in particular on an inner surface of one of its walls 11, 12 at least, the marking tool 7 lifts the end of each arm 70 up to bring it out of the inner volume 6. In one form, in the case where the marking device comprises several arms and is arranged to print several patterns 8 on the same item 1 as is the case here, the arms 70 are driven at approximately the same time to reduce the marking time.

(23) In this form, the substantially horizontal movement of the pad 80 is provided by rotation of the associated arm 70 but it might alternatively be driven, for example, by a translation cylinder. Here, in particularly, the rotation of the arms 70 may be implemented by an actuating device 71, for example by the rotation of a worm or by the translation of a rack aligned with the axis X, the worm or the rack is mesh with one or more toothed wheel(s), each of the toothed wheels being secured to one end 73 of an arm 70 opposite to the distal end 72. In this manner, the toothed wheel, then driven in rotation, causes the movement of the distal end 72 provided with the pad 80.

(24) Moreover, each arm 70 has at least one bend 74 between its two ends 72, 73 oriented outwardly so as to facilitate the access and the introduction of this distal end 72 into the inner volume 6 of the item 1 through its opening. This feature is particularly advantageous when the item should be printed in several patterns 8 and that several arms 70 should be implemented.

(25) Since the manufacturing process allows mass production of glass items 1, and that the marking tool 7 evacuates the end of the arm 70 provided with the pad 80 by bringing it out of the inner volume 6 of the item 1 at each marking, it is possible to implement a pad change step 80 of the marking tool 7 between two marking steps, this without interrupting the manufacturing of the glass items.

(26) This pad 80 changing step can be implemented in an automated manner or manually. The use of the pad 80, being sequenced, a manual change of the pad 80 has low risk for an operator who would be in charge of this step. A safety device may also be provided to inhibit an actuation of the marking tool 7 when handled by an operator during production. The unmarked glass items 1 can then be produced simultaneously during the change, without interrupting or suspending the manufacturing of the glass items.

(27) According to an alternative, the marking tool 7 may comprise a plurality of arms, only some of which are actuated, each of said arms being provided with a different pad 80. In such an form, the pad 80 change step is implemented by selecting the desired pattern 8 and by actuating the associated arm to the pattern selected at the marking step.

(28) Alternatively still, one arm may be provided with several pads 80, 80 each of said pads can be actuated independently relative to the each other. For example, one arm may include a different pad 80 corresponding to each letter of the alphabet and can be actuated depending on a desired combination of patterns 8 to form a word.

(29) It will be noted that in the particular case where it is not the lateral wall 11 of the glass item 1 which is marked, but the wall 12 forming the bottom, only a substantially vertical movement of the tool of the marking tool 7 is implemented.

(30) This marking step is performed when the glass temperature is between 725 and 775 degrees Celsius, such as around 750 degrees Celsius, to provide an improved printing quality, for a marking time of the marking step less than 0.6 seconds and in one form is less than 0.5 seconds so as not to impact the making time of a glass item 1, without deteriorating the quality of the customization.

(31) It will be further noted that, at the marking temperature, and during the press exerted by the pad 80 on the inner surface of the glass item 1, said pad 80 stops naturally because the glass wall is cooled sufficiently when in contact with the pad 80, which may be made of metal, to provide quality printing of the pattern 8, while avoiding any deformation of the glass wall 11, 12 when printing the pattern 8. Such an advantage is also particularly advantageous when the glass item 1, after pressing, has walls 11, 12 whose thickness is greater than 1 mm and in one form is greater than 2 mm.

(32) Advantageously, in the particular case where a plurality of items is marked with the same marking tool 7, there may be provided a cooling device of the pad 80 (not illustrated). Such a cooling device may, for example, comprise an integrated cooling circuit in the pad 80 itself, and/or also comprise one or more blowing nozzle(s) independent of the marking tool 7 and adapted for directing an air jet on the pad 80 between each marking step that said marking tool 7 implements.

(33) In the first case, this is an example of a cooling implemented continuously, even that it can be mastered in the time of pad 80, thanks to the presence of temperature sensors. In the second case, it provides an example of a cooling implemented discontinuously, between each marking step.

(34) Once marked or customized by the pattern 8, the glass item 1 is cooled during a cooling stage (see FIG. 1E) with ventilated air then demolded, that is to say removed from its mold 4.

(35) The demolding is performed by a demolding tool 10 forming the ejection arm inserted through a bottom of the mold 4 to push according to the arrow F5 the item 1 formed beforehand (see FIG. 1F).

(36) A burning step (see FIG. 1G) performed by burners 9 of the cooled and demolded glass item 1 allows, in particular, clearing the glass item 1 from its possible defects and making its glass walls smooth and shining. In this way, the pattern accordingly formed on the glass is also made smooth and shining as illustrated in FIG. 7.

(37) FIGS. 1A to 1G illustrate different steps of the manufacturing process of a hollow glass item 1. It is understood that the same process can be implemented in the manufacturing of a plurality of hollow glass items 1. In this case, the pressing and marking steps are implemented in a substantially concomitantly or simultaneously for distinct glass items 1. More generally, all the steps are implemented concomitantly for distinct glass items 1, this is to speed up the production speed.

(38) In one form, the marking time of the marking step is less than 0.5 seconds, and is also less than the pressing time of the pressing step. In this way, the marking step is carried out in masked time, during shut-down of the table supporting the mold 4 for the pressing of the next glass item.

(39) Glass items 1 are manufactured in line or in mass production and involves the use of adapted equipment. The equipment forming manufacturing unit comprises at least: a mold 4 intended for modeling a predetermined outer shape of the glass item 1 to be manufactured; a forming punch 5; a marking tool 7; and a demolding tool 10. The equipment allows manufacturing of all these hollow glass items 1 so that each glass is manufactured according to the manufacturing process described above.

(40) Such a device allows the subsequent manufacturing of each of the glass items 1.

(41) More specifically, the equipment forming manufacturing unit includes a rotary table on which are successively arranged molds 4, the rotary table being indexed. Each mold is associated with a single glass item 1. Indeed, at each step, the mold moves forward and progresses in a sequenced manner performing a down-time at each step, for example before the gob, that is to say substantially in line with a distribution channel of equipment, then in line with the forming punch, then at the marking tool 7, and then at the cooling nozzles, etc.

(42) It will be noted that in the case of the various forms as illustrated, the demolding tool 10 is associated with the mold 4 so that it follows the corresponding glass item 1 during manufacture.

(43) In this case, the longest step involving the most down-time is the pressing step. Consequently, the marking step is not likely to slow the production speed when performed in masked time. This allows in particular reducing the unit manufacturing cost of a glass item.

(44) The present disclosure is described above by way of example. It is understood that those skilled in the art are capable of carrying out various variants of the present disclosure without departing from the scope of the present disclosure.

(45) The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.