Glass manufacturing – Preform reshaping means – Cylindrical preform
Patent
1996-06-18
1998-08-04
Griffin, Steven P.
Glass manufacturing
Preform reshaping means
Cylindrical preform
65108, 65109, 65276, 65278, 65293, 65297, 65DIG9, 72121, 72122, C03B 23045, C03B 2309
Patent
active
057887330
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a device for the shaping of glass tubes, with at least one shaping tool which can be set in rotational movement and which can be pressed against the circumference of the softened glass tube, in order to produce a contraction of the glass tube, said contraction corresponding to the profile of said shaping tool.
In glass processing machines for producing small bottles from glass tubes, devices of the above type are used for shaping the necks of the bottles. In a relevant device known from DE 17 96 100 B2, the shaping tools formed by a pair of shaping rollers are held by jib arms which are pivotable to and fro in opposite directions and which, during the shaping process, are moved towards the longitudinal axis of the glass tube in such a way that the latter is gripped in a pincer-like manner by the shaping rollers. As soon as contact occurs between the glass tube and the shaping rollers, these are taken up by the glass tube held in a rotating clamping chuck and are set in rotational movement, the final rotational speed of the shaping rollers being determined by the rotational speed of the glass tube, narrow limits being placed on said rotational speed, as is known, in order to avoid a so-called whiplash effect. In the light of the circumstances described, during the shaping of the glass tube the work has to be carried out with comparatively long advances per revolution of the glass tube, since a lengthening of the processing times is out of the question, not only for economic reasons, but also because the cooling curve of the glass opposes it. The relatively long advances per revolution entail the disadvantage that normal and tangential forces are exerted on the softened part of the glass tube and may lead to undesirable deformations, that is to say to rejects being produced.
The object on which the invention is based is to provide a device of the relevant generic type, by means of which, whilst adhering to a processing time predetermined by the softening state of the glass, it is possible to shape a glass tube carefully and with high accuracy by means of short advances of the shaping tools per tube revolution. This object is achieved, according to the invention, in that the device has a turntable which rotates about the longitudinal axis of the glass tube during the shaping process and on which the shaping tool is mounted rotatably and so as to be displaceable perpendicularly to the longitudinal axis of the glass tube.
The device according to the invention makes it possible for the distance, over which the shaping operation takes place during a predetermined shaping time, to be increased markedly in comparison with known constructions, in that the rotational speed of the turntable is increased in relation to the rotational speed of the glass tube, in practise by 5 to 10 times, depending on the dimensions of the glass tube. Furthermore, it is even possible for processing to be carried out on a stationary glass tube.
Further details and features of the invention emerge from the subclaims, the accompanying drawing and its following description.
BRIEF DESCRIPTION OF THE DRAWING
The single drawing FIGURE illustrates, in section, an apparatus for shaping glass tubes, in accordance with the present invention.
The particularly advantageous device represented in the drawing has a turntable 2 which is arranged at the upper end of a drive shaft 1 designed as a hollow shaft and which carries two diametrically opposed shaping tools 3 and 4 designed as ballbearing-mounted profile rollers. The ball bearings 5 and 6 for the shaping tools 3, 4 are mounted on a cylindrical journal 7, the longitudinal axis 8 of which is offset relative to the longitudinal axis 9 of a shaft 10 by an amount which corresponds to half the possible total advance of the respective shaping tool 3 or 4. The cylindrical journal (7) is carried by the shaft 10. Connected fixedly in terms of rotation to the shaft 10 is a gearwheel 11 which meshes with a toothed ring 12 at the upper end of a sleeve 15 supported via ball bearings
REFERENCES:
patent: 2392104 (1946-01-01), Smith
patent: 3171730 (1965-03-01), Zauner
patent: 3360352 (1967-12-01), Sundstrom et al.
patent: 4055977 (1977-11-01), Haswell
patent: 4144732 (1979-03-01), Franks et al.
patent: 4441908 (1984-04-01), Zauner
patent: 4830654 (1989-05-01), Dichter
patent: 5300134 (1994-04-01), Mannl et al.
Dichter Hans-Joachim
Griffin Steven P.
Stone Mark P.
LandOfFree
Device for the shaping of glass tubes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for the shaping of glass tubes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for the shaping of glass tubes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1172726