RU24813U1 - PRESS FORM OF VARIABLE VOLUME FOR MANUFACTURE OF TANKS FROM POLYETHYLENE REFTALATE - Google Patents

Abstract

1. A mold of variable volume for blowing containers of different capacities from heated PET preforms, characterized in that the forming cavity consists of welded cone-shaped and cylindrical parts with a detachable bottom, whose linear movement along the physical axis of symmetry of the mold is controlled by the forming volume using cylindrical bottom inserts. 2. The mold according to claim 1, characterized in that the height h of the cylindrical inserts under the bottom for blowing the containers of the required volume is determined by the calculation according to the formula h - the height of the insert under the bottom, corresponding to a decrease in volume by 0.25 l, mm; V is the required amount of volume change blown capacity, l; 0.25 - the initial value of the decrease in the maximum volume of capacity, l. 3. The mold according to claim 1, characterized in that the upper cylindrical part of the mold is made with annular grooves, which together with the ribs form a radiator.

Description

: .-:,.: ..-. t - .; ® ..; a.SV-sss "S s 6B29C 49 / 94,49 / 42,49AI8

Description of utility model.

"Mold of variable volume for the manufacture of containers from

ethylene terephthalate

RU2121922C1, 11.20.1998. RU2123934C1, 12/27/1998. RU2139190C1, 10.10.1999. US5085822A, February 4, 1999. RU2129957C1, 05/10/1999. WO96 / 30190AL 10/03/1996. RU2172247, 08.20.2001. RU2140853C1, 10.11.1999. RU2164471C1, 03/27/2001. EP0888863A1, 01/07/1999. SU564970A1.10.08. 1977. RU9599U1.16.04.1999.

The mold is designed for the manufacture of small containers (bottles) of various volumes from 0.33 to 2 liters. The area of application of the nress-form of the device for extracting bottles of heated preforms is preforms, the material for which is polyethylene terephthalate (PET).

Structurally, the mold is a combination of cylindrical and conical parts of the shape of the bottle with a detachable bottom (socket). The internal mold-forming volume of the mold is variable, which is achieved by the possibility of moving the attachment in the cylindrical part of the mold.

Molds in the well-known patented installations for blowing containers from heated preforms, as a rule, have a forming unit in the form of a set of interchangeable paired half-forms. Each volume of a pair corresponds to a paired half-form. Thus, a change in the volume of the bottle indirectly entails the need to manufacture a mold corresponding to this volume, and this is a labor-intensive, expensive and material-intensive process. The mass of the paired half-mold for two blown bottles with a capacity of 1.0 liter is 50 kg.

In a removable pair of half-forms, one of them is movable and moves along guides of a sufficiently large diameter from the condition of strength and with high quality processing. A technical solution variant in RU2172247C1, 08/20/2001, provides for the replacement of the translational movement of half-forms by its rotation around an axis fixed in a fixed loop. RU8304, 11.16.98U1, considered a variant of a blow mold for jars, but of a fixed volume and with a dismemberment area in the upper or middle part. However, the mentioned technical solutions do not exclude the need to have a set of half-forms for different volumes of containers.

The process of loading open paired half-forms and extracting blown containers is carried out manually, i.e. the operator’s hands are in contact with the moving parts of the blowing unit. In RU2172247C1, 09.27.2000. It is planned to use a special manipulator and spring-loaded the bottom of the fixed half-mold with a spring mechanism to facilitate the unloading process, but the volume of the molds remains unchanged, despite the significant complication of the loading and loading unit.

A block of interchangeable paired half-molds by design features limits the productive capabilities of PET blowing units. The design features include the mandatory water forced cooling in the process of blowing containers from PET.

Thus, the need is seen for a universal simple design of the mold, which can replace a pair of interchangeable half-molds for the manufacture of small containers up to 2 liters, increase the safety of the blowing installation, and eliminate forced cooling.

Accordingly, the constructive use of the proposed mold solves pressing problems, namely:

-increase safety when loading and unloading bottles;

-increase the performance of the installation of blowing;

-the ability to easily automate the loading of inflated bottles;

-exclusions of the need for forced cooling. The utility model is illustrated by drawings, which depict:

FIG. 1 - embodiment of the mold varies in cross-section;

FIG. 2 - change in the volume of mold formation using inserts;

FIG. 3 is an embodiment of installing molds on a plate of a blowing device (mold block).

The cylindrical part of the mold 1 (Fig. 1) is made of a pipe with a diameter of 102 mm with a wall thickness of 7 mm, and after appropriate processing is connected by welding to a conical part 1, the external surface of which has ribs and annular grooves forming a radiator 8 (Fig. 1 )

The connected cylindrical and conical parts form the movable upper part 1 of the mold. Donshiso 2 is rigidly attached to the plate with a bolt 3. The extruded diameter of the donppka is equal to the inner diameter of the cylindrical part. In the process of blowing, the cylindrical part 1 is pushed onto the bottom 2, closing the volume of the formation of the bottle. A change in the volume of forming is achieved by installing 2 inserts “in a cylindrical shape under the bottom” (Fig. 2).

The geometric size of the inserts "in provides a decrease in the capacity of the blown bottle by the required amount. In the proposed embodiment, the geometric size of one insert with a height h reduces the volume of the blown bottle by 0.25 liters.

Insert height hp to reduce the mold volume by the required value is calculated by the formula:

where A is equal to 43.4 mm;

U „is the required value of the change in the volume of the blown capacity. Moreover,

may be equal to more or less 0.25 liters.

The increase in the number of blown containers in one cycle is achieved by mounting on the pin 4 (Fig. 1) a device for blowing several molds (mold block).

The authors propose the option of installing a universal mold of different sizes, three in a row (Fig. 3) for a semiautomatic device blowing the development of the scientific production enterprise Spetspromavtomat.

This technical solution solves the problem of blowing for one cycle of containers of different displacement when changing the internal volume of the installed compression molds. A block of three cress forms of different volumes weighs 6.1 kg and is significantly less than the weight of the bunk mold on two bottles.

After the end of the blowing process, unloading the bottles involves the separation of the upper part 1 of the mold from the bottom 2 and the opening of the bottom of the mold, which makes it possible to automate the loading process.

The authors developed and implemented on a semiautomatic device for blowing containers a rotary automatic mechanism for unloading bottles from the cavity of the mold at the end of the blowing process. An automatic unloading mechanism transfers the mold block to the unloading zone, where after opening the holding locks with the help of special pushers, the blown bottles are pushed out of the mold cavity. Pushers are driven by a pneumatic scraper, which eliminates manual unloading and injuries to the operator.

The loading of the mold block is also safe, since the heated preforms are lowered into the open neck of the mold (Fig. 1).

h.h - mm, 0.25

surfaces with the external environment create an acceptable thermal regime of blowing without additional water cooling.

Thus, the application of the proposed design of a universal mold of variable volume allows us to fix the previously mentioned technical and operational problems of manufacturing PET containers for small containers.

Claims (3)

1. A mold of variable volume for blowing containers of different capacities from heated PET preforms, characterized in that the forming cavity consists of welded cone-shaped and cylindrical parts with a detachable bottom, whose linear movement along the physical axis of symmetry of the mold is controlled by the forming volume using cylindrical inserts under the bottom. 2. The mold according to claim 1, characterized in that the height h _{p of the} cylindrical inserts under the bottom for blowing containers of the required volume is determined by the calculation according to the formula

where h is the height of the insert under the bottom, corresponding to a decrease in volume of 0.25 l, mm;
V _p - the required value of the change in the volume of the blown capacity, l;
0.25 - the initial value of the decrease in the maximum capacity, l. 3. The mold according to claim 1, characterized in that the upper cylindrical part of the mold is made with annular grooves, which together with the ribs form a radiator.