WO2007034269A1

WO2007034269A1 - Stemmed glass tumbler forming apparatus

Info

Publication number: WO2007034269A1
Application number: PCT/IB2006/002445
Authority: WO
Inventors: Wladimiro Lumare
Original assignee: Olivotto Glass Technologies S.P.A.
Priority date: 2005-09-23
Filing date: 2006-08-28
Publication date: 2007-03-29
Also published as: ITTO20050656A1

Abstract

Two gripping devices (10, 33) that are vertically movable under control of respective actuators are adapted to retain the foot and the lip of a vertically hanging, upside-down cup and to move away from each other to stretch the neck of the cup, which is made plastic by a nozzle heater (54), to form a thin stem. An annular heater (30) then melts a thin annular area of the cup to detach its moil, which drops by gravity and is unloaded.

Description

STEMMED GLASS TUMBLER FORMING APPARATUS

The present invention relates to a stemmed glass goblet forming apparatus, and more precisely to an apparatus for transforming a hollow glass cup or blank into a long- stemmed goblet.

In the production of long-stemmed glass goblets, a stemless cup is initially manufactured, for example by means of a press-and-blow machine of the type described in IT-2003-A- 623, then the almost cold cup is transferred, at first, to a stretching apparatus, where the foot of the cup is heated again to its plastic state and is mechanically stretched to form the stem. Subsequently, the so-shaped goblet is transferred to a cutting machine, where an annular scrap, so-called "moil", which was used during the machining for manipulating the goblet, is removed from the mouth of the goblet. This removal of the scrap generally concludes the goblet-manufacturing operations, except for possible finishing operations, such as annealing, and the like.

With the known stretching-and-cutting process, a loading machine delivers the cup, in an upright position, to the stretching apparatus, which grips the lip of the cup, while a lower gripping device grips the foot. The neck of the foot is then heated by nozzle burners, and the lower gripping device is progressively lowered, thereby stretching the neck of the foot to form the stem. After cooling, the goblet is drawn by an unloading machine, is turned upside down, and then is trasferred to a subsequent moil-cutting device.

The above process requires various transfers and manipulations of the article under processing, each of which is a complex and delicate operation. The cup at first is transferred from the press-and-blow machine to the stretching machine, and then from the latter to the final, cutting machine. Each of these transfers not only lengthens the production times, but gives rise to a certain percentage of breakages or scraps too.

Furthermore, both the stretching and the cutting machine usually are complex carousel machines, which consequently have a considerable intrinsic cost, to which the cost of the machines for loading/unloading the articles from one station to the next one must be added.

Therefore, it is a main object of the present invention provide the formation of the stem and the removal of the "moil" in a single machine.

It is another scope of the invention to reduce the total cost of the apparatus for stretching and cutting the goblet.

The above object, together with other scopes and advantages that will clearly appear from the following description, are achieved by the invention with a stemmed glass goblet forming apparatus having the features recited in claim 1. The dependent claims state other innovating, though secondary features of the invention.

The invention will be now described in more detail on the basis of a preferred embodiment and with reference to the attached drawings shown by way of non limiting example . In the drawings :

Fig. 1 is a broken away view in side elevation of a long-stemmed glass goblet forming apparatus according to a preferred embodiment of the invention;

Fig. 2 is a plan view from above of the lower part of the apparatus of Fig. 1, in a slightly reduced scale;

Figs. 3-8 are views similar to Fig. 1 showing the forming apparatus in a few subsequent operative steps, in a significantly reduced scale.

With reference to Fig. 1, an upper gripping device 10 comprises a support 12 that is vertically movable under control of an actuator (not shown), such as a pneumatic cylinder. Tie rods 14 project downstream from the support and sustain a horizontal pad 16 made of an elastomeric material. Three jaws 18 (only one jaw is shown in Fig. 1) are equally spaced around pad 16 and are pivoted to move between an open position (shown with dashed lines) and a close position, in which they bias against pad 16 to clamp the foot of an upside-down glass cup 20, as will be better described below.

The jaws are operated via connecting rods 22 by a spider 24 that is vertically slidable under control of a pneumatic cylinder 26, against the returning action of compression springs 28. Therefore, the jaws are normally close under the returning action of the springs, and may be opened by operating cylinder 26.

An annular burner 30, that will be further described below, is coaxially arranged below gripping device 10 and is supported at an invariable height by a stationary bracket 32.

A lower gripping device 33 is mounted below annular burner 30 and comprises a support 34, which is vertically movable under control of an actuator (not shown) and has a rod 36 housed therein which is slidable coaxial to annular burner 30 and supports a plate 38 having a guide 40 that slidably engages the upper end of rod 36 for centering purposes.

A few equally-spaced jaws 42 (only one of which is shown in Fig. 1 for better clarity) are pivoted about respective horizontal axes and engage the lower lip of cup 20, as will be described below. Jaws 42 are provided with respective toothed sectors 44 that mesh with a cylindrical rack 46 surrounding rod 36 and slidable within a vertical seat in support 34.

Rod 36 is elastically pulled downwards by a helical spring 48, but can be pushed upwards by a pushing member 50 arranged below. In its movements, the rod draws rack 46 via a partially yelding connection consisting of a helical spring 52.

Finally, having now reference also to Fig. 2, the goblet forming apparatus comprises a nozzle-burner heater 54 provided with an arcuate yoke 56 which supports a plurality of nozzles 58 and is movable horizontally between a withdrawn position, as shown in Fig. 1 , and an overhanging position (shown with dashed lines in Fig. 2) in which yoke 56, and consequently nozzles 58, surround the neck of cup 20 for heating it, as will be described below. Heater 54 is supported on support means and actuators not shown as obvious to the person skilled in the art.

Having reference also to Figs. 3-9, the operation of the above-described forming apparatus will be now described. While gripping device 10 is in its raised position, a conventional loading device (not shown as obvious to the person skilled in the art) delivers cup 20 to it in an upside-down position, by bringing the cup foot near to pad 16. Then jaws 18 are closed for sustaining the upside-down cup (Fig. 1). Then the gripping device is lowered (Fig. 3) and passes through annular burner 30, until the lower edge contacts plate 38, then jaws 42 close around the bead that delimits the edge of the mouth of the cup under the action of return spring 48.

Yoke-shaped heater 54 now moves forward and surrounds the cup (Fig. 4), and the nozzles are ignited for heating the glass of the neck to its plastic state. While the glass becomes plastic, gripping member 10 is raised, whereby the neck of the cup is progressively stretched to form a stem (Fig. 5). At this step, the foot of the cup is clamped between pad 16 and jaws 18, while the lip is clamped between plate 38 and jaws 42.

At the end of the stretching of the stem, yoke-shaped heater 54 is withdrawn, and the cup progressively becomes cold. At this point, pushing member 50 raises rod 36 to open jaws

42, and support 34 is lowered of a few millimeters in order to slightly move plate 38 away from the lip of the cup (Fig. 6), while the cup is still retained by gripping member 10.

Annular burner 30 is ignited to project an intense, laminar heat flux onto the desired cutting area of the moil to cause the local melting of the glass, thereby causing the moil to detach and to drop on the plate immediately below.

Support 34 is now lowered (Fig. 7) by its actuator (not shown) until it is completely disengaged from annular burner 30 and braket 32, while rod 36 makes an extra-stroke in order to raise plate 38 with respect to support 34, thereby disengaging the plate from jaws 42 in a vertical direction. The moil is now unloaded from the plate (Fig. 8) by any suitable known means, such as a transversal air blow or a push-away shovel, such as the shovel that is diagrammatically referred to with 60.

Finally, gripping device 10 is raised again for disengaging the finished goblet from burner 30 and nozzle heater 56, the goblet is gripped by an unloading device (not shown), jaws 18 are opened, and the goblet is drawn away.

Of course, as usual in the technique of machining hollow glass, and as will be obvious to the person skilled in the art, for better uniformity of the thermal treatment, during the stretching process the upper and lower gripping devices are preferably wheeled synchronously about their common axis, and the same rotation can also be provided during the cutting operation.

The loading/unloading of the cups to/from the upper gripping device can be performed by anyone of the suitable loaders or unloaders known to the person skilled in the art, because the delivery and the drawing of a hollow glass article to/from a gripping device as described above does not give rise to any specific problem that could require particular tricks. Therefore, the loaders and unloaders are not described herein and they are not within the scope of the invention. The above described device is normally destined to be incorporated in a multiple machine, for example a rotative machine comprising a few tenths of such devices mounted on a rotating carousel cooperating with a conventional loader and a conventional unloader which are arranged at predetermined stationary positions along the periphery of the carousel. The general organization of such machine does not belong to the invention and will be obvious to the person skilled in the art.

A preferred embodiment of the invention has been described herein, but many changes to the various parts are possible within the scope of the inventive concept. Therefore, the upper gripping device, rather than a jaw-based device, could be a sucker-based device having a seat for receiving the foot of the cup, to which an air suction is applied. The heater shaped as an arcuated yoke with nozzles could also be modified, for example, it could comprise two semi-lunar members adapted to close around the cup. The lower gripping device could also be different from what shown in Fig. I₅ both in the shape of the jaws and in the driving mechanism, as well as in the shape of the plate, also in relation to the unloading of the scrap. Finally, it is evident that the approaching movements and the movements of the parts away from each other, particularly of the two gripping devices, could be obtained with relative movements of a different type.

Claims

1. A stemmed glass goblet forming apparatus, characterized in that it comprises:

- an upper gripping device (10) movable vertically under control of first driving means and adapted to retain the foot of a cup (20) hanging vertically in an upside-down position;

- a first heater (54) movable between a disengaged position and a position surrounding the cup near the foot, and adapted to locally heat the cup to its plastic state;

- a lower gripping device (33) coaxially arranged below said upper gripping device (10) and adapted to grip the lip of the mouth of said cup;

- a second annular heater (30) coaxially arranged between said two gripping devices, and adapted to locally heat an annular area of the cup to cause the melting thereof;

whereby the relative movement of the upper gripping device and the lower gripping device away from each other, while they respectively retain the foot and the lip of the mouth of a cup, and the first heater heats an intermediate area between the foot and the cup, causes the formation of said stem, and whereby, after release of the lip of the cup by means of the lower gripping device and the relative approaching of the upper gripping device to the annular heater, the latter causes an annular scrap of the cup to detach and to drop.

2. The stemmed glass goblet forming device of claim 1, characterized in that the lower gripping device (33) also is vertically movable under control of second driving means, whereby it can move away from the upper gripping device (10) at the time of loading/unloading the goblet or cup.

3. The stemmed glass goblet forming device of claim 1 or 2, characterized in that the upper gripping device (10) comprises a pad (16) and a number of jaws (18) arranged around the pad and adapted to close against the outer edge of the foot of said cup.

4. The stemmed glass goblet forming device of claim 1 or 2, characterized in that the upper gripping device (10) comprises a sucker-based locking device adapted to act upon the lower surface of the foot of the cup under processing.

5. The stemmed glass goblet forming device of any of claims 1 to 4, characterized in that the lower gripping device (33) comprises a plate (38) for supporting the lip of the cup and a number of jaws (42) arranged around the plate and adapted to close against an end bead of the mouth of said cup.