RU2213660C1 - Device for manufacture of articles by inflation - Google Patents

Abstract

FIELD: devices for formation of various articles, in particular, of plastic materials. SUBSTANCE: the device has half-moulds with a mechanism of their jointing and confinement, mould stretching assembly, block inflation assembly. The mould stretching assembly is installed on a movable platform that is linked with the half-mould by means of rods. The movable platform and half-moulds are hinge-joined by rods. The mould stretching assembly has a spring-loaded air cylinder installed on the movable platform and can be removed and a stretching air cylinder installed on it. A compactor is installed on the upper cover of the stretching air cylinder and has a hole, through which compressed air from the inflation assembly is fed to the mould. EFFECT: reduced overall dimensions of the device and enhanced efficiency of its operation. 1 dwg

Description

 The invention relates to devices for forming various products, in particular from thermoplastic materials.

 A device for the manufacture of containers such as bottles by blowing from preheated thermoplastic blanks, which contains half-molds with a mechanism for their closure, a device for sealing and stretching the preforms that are mounted on the bed (see patent RU 2129957 C1, CL 29 C 49/28 publ. 10.05.99). The mechanism for moving the preform stretching device by means of rigid joints is fixedly mounted on the bed and fixedly connected to the half-molds.

 Also known installation for the manufacture of containers of platmas, consisting of a bed on which the parts of the mold (movable and fixed) are installed (see RU 2139190 C1, CL 29 C 49/00, publ. 10.10.1999). The blowing module is installed on the crossbar, with which the frames are connected, on which the mold parts are also installed. These frames and the crossbar are brutally connected to the bed and are power elements that provide rigidity and structural strength.

 In these known devices, the force from the mechanism of movement of the rod, the tensile preform, is transmitted to the frame, the frame of the mold, which forces them to make more durable, with a large mass.

 The closest analogue of the device according to the invention is a device for the manufacture of plastic products by blowing, containing mold half-molds with a mechanism for their closure and retention, a preform stretching unit, including a compressive tensile pneumatic cylinder mounted on the platform, a blank inflating unit, and the platform is connected to the press semi-molds forms of articulated levers (autosw. SU 509437 A, class B 29 C 49/28, publ. 05/04/1976).

 The disadvantages of this and other known installations is that all the efforts from the blowing mechanism — the workpiece stretching and the half-molds that occur when the molds are closed — are transferred to the supporting structural elements of the machine on which the mold is installed — the frame (bed). To impart stability and structural strength, the metal consumption of these elements is increased, the installations have a large mass and are complex in design.

 The technical result of the invention is to reduce the size of the device for the manufacture of plastic products by blowing with increasing efficiency.

 The invention is aimed at achieving a technical result, which consists in creating such a molding unit in which all dynamic forces from working mechanisms, namely those arising from the action of working pneumatic cylinders (tensile and compressive), will not be transmitted to the supporting structural elements of the machine, but will be redistributed in a closed the contour inside the mechanism (between the half-plate plates and the pneumatic cylinders). This will make it possible to reduce the metal consumption of the entire structure due to the lightening of the frame (bed) or complete elimination, to reduce the dimensions of the device while increasing the efficiency of its work and the ability to use this design not only in production shops, but also at home. The degree of freedom of such a device is not more than 5.

 The technical result indicated by the applicant is achieved due to the fact that the device for manufacturing plastic products by blowing contains mold half-molds with mechanisms for locking and holding them at a minimum distance between them, a preform stretching assembly including a clamping pneumatic cylinder mounted on a movable platform and mounted on a stretching pneumatic cylinder, and a workpiece inflating assembly, while the movable platform is connected to the mold half-forms by means of rods articulated, and The heater installed on the top cover of the stretching pneumatic cylinder has an opening through which compressed air from the blowing unit is supplied to the preform.

 The invention is illustrated in the drawing, which shows a device for the manufacture of plastic products by blowing.

 A device for the manufacture of various types of products, in particular plastic blow molded products, consists of two mold half-forms 1a and 1b (although their number is not limited), which, closing by a mechanism (not shown), move on rolling or sliding bearings, which freely move along the guides 2 connected to the frame 3 of the structure. The presence of such guides is optional, the half-molds can move on any surface, preferably having a low coefficient of friction to reduce the efforts spent on their closure. The half-molds on the outside have “earring” fastenings 4a, 4b, to which metal rods 5a, 5b, corresponding to the loads, are attached at one end to the loads (or from any other material). These rods with opposite ends are pivotally connected to the platform 6.

 The drawing shows a design with two rods, each of which is attached to one half-mold. Their number can vary, as well as the number of half-forms. Thus, the platform 6 hangs freely on the above rods 5 and gets the opportunity to make movements consistent with the mold half-forms. On the platform without special fastening, also with the possibility of removal, a preform stretching unit 7 is installed, which includes a compression cylinder 8 and a stretching pneumatic cylinder 9 mounted on it. The pneumatic cylinder 9 has a retractable stretching rod 10. A seal 11 mounted on the top cover of the pneumatic cylinder 9, has an opening through which compressed air from the blowing unit (not shown) is supplied to the preform and inflates it to a predetermined size. The seal 11 is a ring that seals the neck of the preform, fixed by the inner diameter formed when the half-forms are closed on their lower face.

 The proposed device operates as follows.

 The mold half-molds 1a and 1b are brought to the minimum distance to each other by means of a closing mechanism for the half-molds. Between them in the formulating space place the preform. Next, a compression pneumatic cylinder 8 comes into operation, which raises the stretching pneumatic cylinder 9 towards the half-molds. A seal 11 is mounted on the top cover of the tensile pneumatic cylinder, which is fed to the hole for the tensile rod 10 in the mold half-molds and seals the formed space. The rod 10 stretches the workpiece in its axial longitudinal direction to a predetermined final length, and then compressed air is supplied from the blower assembly (not shown) through the gap between the rod and the seal, which inflates the workpiece in the form of the internal forming surface of the mold. The installation of a movable pneumatic cylinder 8 under the tensile 9 makes it possible to reduce the distance from the stretching pneumatic cylinder to the half-plate plates by at least the total length of the movable pneumatic cylinder. Thus, the linear dimensions of the blowing module are reduced by eliminating the need for a special tensile rod moving through the sealing pneumatic cylinder. A conventional tensile air cylinder is used.

 The pneumatic cylinder 8, having a protrusion on its lower surface, is installed in the groove of the platform 6. Thus, it simply rests on the platform. The pneumatic cylinder 8 can be installed on the platform 6 (base plate) without mounting and, if necessary, it can be replaced by another without any special additional effort.

 Since the platform 6 of the preform stretching device is movable and connected with the mold half-molds, it is possible to install it without additional efforts parallel to the plane of the lower face of the half-molds at the moment of contact of the sealing ring 11 and the mold half-molds. This makes it possible to ensure the most tight fit of this rubber ring, which most fully seals the inner space of the preform and, as a result, will increase the efficiency of the blowing device.

 Dynamic forces from the pneumatic cylinder block (preform stretching device) will not be transmitted to the supporting parts of the structure, but will be redistributed inside. The “half-form-pneumatic cylinders” mechanism is closed to itself by means of rods which, with the help of “earrings”, connect the preforms and the support of the pneumatic cylinders. This mechanism can be used without an external frame.

 Thus, the forces from the stretching device of the preform and the claimed device arising from the formation of the product by blowing will be redistributed in a closed loop without affecting the supporting structural members, frame (bed). This will reduce the metal consumption of the device, reduce its weight while increasing the efficiency of its work.

 The device has a simplified design, low cost, it is convenient for installation and maintenance.

Claims (1)

 A device for the manufacture of plastic products by blowing, containing mold half-molds with a mechanism for locking and holding them at a minimum distance between them, a preform stretching unit, including a pressing pneumatic cylinder mounted on a movable platform and a stretching pneumatic cylinder mounted on it, and a blank inflating unit, while the movable platform is connected to the mold half-forms by means of rods pivotally, and the seal installed on the top cover of the stretching pneumatic cylinder has a hole through which compressed air from the blowing unit is fed into the preform.