CZ2003219A3 - Forming process of small glass blank pressings - Google Patents

Abstract

The invented process for forming small glass blank pressings (8) is characterized in that a rolled strip (4) of hot glass melt is supplied into a through hole (5) of a compression mold (2). In said compression mold through hole (5) a gob of glass is cut from the rolled strip (4) by a punch (7) producing a front or backside of the blank pressing (8). Between a first (7) and a second punch (9) and said mold (2) body, there is formed an opposite side of the blank pressing (8). After removing excess parison of the strip (4) by performing backward motion of the first punch (7) said blank pressing (8) is pushed out by the second punch (9) from the mold (2) body.

Description

Method of shaping small glass moldings

Technical field

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to machine forming small glass moldings.

BACKGROUND OF THE INVENTION

For machine shaping of small glass moldings without overprinting, so called shot, machines are used for metal-free forming of chandelier heads and trimmings on the principle of glass presses in special design and metal-free creep machines, so-called crushers. The creepless creeping machines are provided with a mold formed by a mold body, in which a through hole with a cross-section in the shape of the plan of the product is formed and accommodates two sliding punches forming the front and back sides of the molding. Further, a dispensing opening is formed in the mold body with an axis perpendicular to the axis of the working opening. In the known process, an exact batch of glass is usually formed in the form of a ball, the weight of which is equal to the weight of the future molding. Enamel dose - the ball is heated and introduced into the dispensing opening. After closing the working space of the mold with one punch, the second punch moves the enamel batch through the working opening to the working space where the product is molded.

The disadvantage of problem-free shaping of chandelier heads and trimmings is the repeated dosing of low-weight glass and the undesirable dispersion of batch weights which adversely affects the height of the compact.

The disadvantage of the method of shaping by means of the creep-free creeping machines is the necessity of an accurate batch of glass produced by the intermediate stage of production, while the preparation of warm and high-precision batches of glass is technically difficult and economically demanding.

SUMMARY OF THE INVENTION

The disadvantages of the present invention are eliminated by the method of forming the small glass moldings according to the invention. SUMMARY OF THE INVENTION The invention is based on the fact that a rolled hot-melt strip of a specified thickness is introduced into a through-hole of a mold, the body of which also has a cross-sectional through-hole in the circumferential part of the article. The glass gob is cut from the tape by a first punch that forms the front or back side of the molding, the opposite side of the molding being formed by the second punch when the article is molded between the first and second punches and the mold body. After molding the product whose height of the peripheral portion is equal to the thickness of the rolled glass melt, the excess glass melt is pulled up to the inner wall of the through hole by the backward movement of the first punch and the molding is pushed out of the mold body by the second punch.

The process according to the invention eliminates the technically and economically demanding intermediate step of producing a precise batch of glass.

Overview of the drawings

The accompanying drawing shows an embodiment of the invention. Fig. 1 is a cross-sectional view of a mold with a rolled glass melt; Fig. 2 shows cutting and molding of the molten glass by movement of a punch; Fig. 3 shows withdrawal of the remainder of the molten glass ribbon;

DETAILED DESCRIPTION OF THE INVENTION

The hot glass of circular cross-section 1 (FIG. 1) is rolled by a pair of rollers 3 with adjustable axial spacing to the molten glass strip 4 which is introduced into the through hole 5 of the mold body 2. By changing the axial pitch of the rolls 3, the desired thickness of the glass strip 4 is adjusted. 2 shows cutting of the glass gob from the strip 4 and pressing the molding 8. The mold body 2 has a working opening 6, the cross section of which has the shape of the periphery of the molding 8. The working opening 6 has slidingly mounted punches 7 and 9 forming and the reverse side 13 of the molding 8. The movement of the punch 7 discharges the glass gob from the strip 4 and molding the blank 8, the distance between the punch 7 and 9 being equal to the thickness of the glass glue 4. up to the inner wall 10 of the opening 5 by the movement of the punch 7, the molding 8 remaining in the working opening 6 of the mold body 2. In the direction of the arrow (FIG. 4), the glass ribbon 4 is released from the punch 7 and at the same time the punch 9 is moved in the direction of the arrow which pushes the compact 8 from the working hole 6 and the compact 8 falls out of the mold body.

Industrial applicability

The molding process according to the invention can also be used for precision pressing from other materials, such as plastics.

Claims (1)

Patent claims Method for forming small glass moldings (8) in a mold with two punches (7,9) transversely displaceable in a working opening (6) with a cross-section in the form of a peripheral part of the molding (8), characterized in that the strip (4) hot glass having a specified thickness south introduced into the through hole (5) of the die, in which the glass gob ejects the woman (4) through the first punch (7) forming the face (12) or back (13) side of the molding; = ku (8) and the subsequent pressing of the compact (8) between the first (7) and second punch (9) and the mold body (2), the opposite side of the compact (8) is formed and after the excess glass has been withdrawn (10) of the bore (5) by the backward movement of the first punch (7) and the molding (8) is pushed out of the mold body (2) by the second punch (9).