RU2458793C2 - Automatic pet-package blower - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to blowing hollow PET-containers. Proposed automatic blower comprises workpiece conveyor, heating furnace, PET-container blowing mechanism and mould closing mechanism. The latter is arranged inside container and consists of two fixed plates including frames, power cylinders and stops, and moving plates arranged the formed and including frames, moving plate retainers and closing cylinders with their cases attached to fixed plate frame via bracket. In blowing, high-pressure air from preheated preform creates counter pressure to rule out lengthwise opening of the mould due to crosswise fixing of retainers between moving plates with fixed half-moulds and power cylinders that prohibit opening of moving plates in filling molds with high-pressure air (up to 4.0 MPa).

EFFECT: creation of backup pressure, ruled out lengthwise mould opening in blowing.

7 dwg

Description

The invention relates to devices for the manufacture of hollow plastic products such as PET by molding by internal pressure.

A known installation for the manufacture of containers from hollow products, consisting of a bed and a pneumatic motor placed on it, a kinematic drive including a rocker arm, rods and trunnions, fixed frames and movable plates with molds, a hood assembly, a blower assembly including a sealing pneumatic cylinder and a blowing head , pneumatic automation unit (Multipurpose machine for blowing plastic bottles, model QCS-6 (China), accepted for operation according to the certificate of the Altai Center for Standardization, Metrology and Certification, 1996).

The disadvantage of this installation is cumbersome due to the large size of the kinematic assembly and the power piston, designed for tight closing and locking of the mold.

These shortcomings were eliminated: reducing the dimensions and weight, simplifying assembly and installation, increasing the reliability of the installation and unifying individual components, reducing the installation cost was achieved in domestic developments, in particular in the installation for the manufacture of containers made of plastic, consisting of a bed and placed on it a pneumatic motor, a kinematic drive, fixed frames and movable plates with molds, a blower assembly, an exhaust assembly and a pneumatic automation assembly, an air motor is used as a pneumatic motor rotary type, molds are located on opposite sides of the rotary type air motor, the kinematic drive is made of two identical nodes parallel to each other, each node being folding, and the blowing unit and the extraction unit form a blowing module (RU 2139190, В29С )

Closest to the claimed invention is a technical solution RU 11137, 1999, В29С 49/42 - installation of molding plastic containers by blowing, including a bed on which are mounted a conveyor belt and mechanisms for rotating and setting the blanks, a heating device, a locking mechanism for locking molds with levers and device for transporting workpieces and finished containers, a mechanism for stretching and blowing containers, a pneumatic control system of mechanisms with a compressed air supply circuit to which are connected all pneumatic cylinders and compressed air supply circuit for blowing blanks. In this known solution, the locking mechanism of the molds is used to ensure parallelism of the locked and fixed molds. A disadvantage of the known installation is that the stops used in it do not provide sufficient back pressure to exclude the longitudinal opening of the pres-forms at the time of blowing.

The task to which the claimed technical solution is directed is to provide back pressure during the drawing and formation of the PET product with high pressure air from the heated preform inside the mold block. In this case, backpressure, excluding the longitudinal opening of the molds at the time of the preliminary and main blowing of the product, is created due to the transverse fixation of the mechanism stops between the movable plates with fixed half-molds and power cylinders, which at the time of filling with high pressure air (simultaneously with the preliminary and main blowing of the product ) carry out the retention of movable plates from disclosure.

In this scheme, the high-pressure air source for blowing PET products and backpressure retention of the blowing unit is a common air system, the adjustment and distribution of which is carried out by means of a valve block controlled by a programmable controller.

A feature of this scheme is the exclusion of mechanical retention of movable plates, which does not lead to natural wear of the structure due to the absence of movements causing friction of individual elements. It also ensures the proportionality of the created holding pressure due to a single air supply source.

The technical result of the claimed invention is to ensure the creation of back pressure and the exclusion of the longitudinal opening of the molds at the time of blowing.

The technical result of the claimed invention is achieved due to the fact that the automatic machine for blowing PET containers includes a conveyor for moving blanks (forklift), a heating device (oven), a mechanism for blowing PET containers and a locking mechanism for molds (power unit). The locking mechanism of the molds (power unit) is located inside the container and consists of two fixed plates containing frames, power cylinders and stops, and located between the fixed plates of moving plates containing frames, locking mechanisms of moving plates and locking cylinders, the body of which is fixed to the frame of the fixed plate through the bracket, in this case, when the PET containers are blown out with high pressure air from the heated preform, counterpressure occurs, which excludes the longitudinal opening of the molds at the time of blowing out the PET containers, which creates is due to the transverse fixation of the stops between the movable plates with fixed half-molds and power cylinders, which at the time of filling the molds with high pressure air up to 4.0 MPa carry out the retention of the movable plates from opening.

The invention is illustrated by figures 1-7, which show the main elements of the machine.

Figure 1 - General view of the automatic blowing machine for PET containers

Figure 2 - container

Figure 3, 4 - oven

Figure 5 - section of the furnace

6 - power plant

7 - autoloader

The machine for blowing PET containers includes a conveyor for moving blanks (autoloader), a container 1 in which a preform heating unit 2 (oven) is installed, and a locking mechanism for locking molds 3 (power unit), a mechanism for blowing PET containers, consisting of a base 49 , a bottom lifting mechanism 61, an upper plate 62, a locking and blowing assembly 63, a valve block and distributors 70, two fixed plates 50 (each comprising a frame 51, a power cylinder 52 and stops 53), two movable plates 54 (each containing a frame 56, locking mechanism of movable plates 57 and locking cylinder 58, housing to which is fixed to the frame of the fixed plate through the bracket 59, and the rod to the frame of the movable plate through the bracket 60), while during the blowing of the PET containers from the heated preform with high pressure air (up to 4.0 MPa) backpressure is created by the power cylinders 52, which due to the transverse fixation of the stops 53 between the movable plates 54 with fixed half-molds and power cylinders 52 prevents the longitudinal opening of the movable plates 54.

The container 1 performs the function of a fence, the frame 7 of which can be made in two versions: prefabricated from individual purchased elements (profiles), or a welded frame with doors and panels made of sheet metal. The frame 7 of the container 1 is mounted on the base 8, which has a welded structure of a standard profile and sheet. A furnace 2 and a power plant 3 are also installed on the base. A control cabinet 5 and a control panel 6 are mounted on the frame 7. Inside the control cabinet 5, electronics and electrical equipment are mounted on a common panel. The control panel 6 has a programmable terminal and controls the basic functions of the machine.

The furnace 2 installed inside the container consists of a frame 9 welded from metal pipes of rectangular cross section and sheet metal. In the frame 9, preform heating blocks 10 are installed consisting of a duct 16, reflectors 11, lamp holders 12, halogen lamps 13, a fan for blowing the ends of the lamps 14 and supports of the preform heating unit 15. Due to the grooves made in the supports 15, it is possible to move the heating block preform 10 in horizontal and vertical directions. Several heating units 10 are installed on the furnace, which are connected at the bottom of the duct 16 by a channel of the hot air exhaust system 17, consisting of duct 18, a fan 19, and also connecting elements and gates 20. From the side of the reflectors 11, the preform heating blocks 10 are connected the channel of the boost system 21, consisting of a duct 22 and a fan 23.

The upper platform 24 of the frame 9 forms a channel, on the sides of which two collectors 25 are made, made of a profile having a cavity for the passage of coolant. A mechanism for moving the preforms 26 is also installed on the upper platform 24 of the frame 9, which consists of a frame 27 with bearing assemblies 28 mounted on it, in which two shafts 29 with mounted sprockets 30 are connected, connected by a chain 31. As a result, two parallel chain gears are formed interconnected by slats of carriers 32, on which rotators 33 are mounted, consisting of a cone 34, a housing 35 with axes of rotation and a gear pulley 36. Along the gear pulleys 36 on the frame 27 of the mechanism for moving the preform 26 is angled a profile with a toothed belt 37 fixed to it. The length of the profile with the belt 37 corresponds to the length of the straight section of the chain 31. A duct casing 38 is mounted on top of the frame 27, on one side of which a radiator (heat exchanger) 39 and fan 40 are fixed.

To ensure movement of the mechanism for moving the preforms 26, a gear motor 44 is mounted on the upper platform 24, which is connected by a chain gear 41 with an asterisk mounted on the shaft 29. On the opposite side, the shaft 29 of the mechanism for moving the preforms 26 by transmitting rotation through the sprocket and chain mounted on it the transmission 42 drives the bevel gear connected to the turnstile 43. Before the turnstile 43, under the upper platform 24, a shutoff device 45 is mounted. On the opposite side, under the upper platform 24, a mechanism g ebenki 46, consisting of a bracket with the sequence of execution slots arranged at a constant pitch with respect to each other, as well as cross-drives 47 and 48 longitudinal movement of the comb 46.

A power plant 3 is also installed inside the container 1. At the bottom of the power plant 3 there is a base 49, which is a metal structure welded from a standard metal profile and sheet. Two fixed plates 50 are installed on top of base 49, which consist of a frame 51, a power cylinder 52, and stops 53. Two movable plates 54 are also installed on base 49, which are fastened to the base 49 via rail rails 55. Movable plates 54 consist of a frame 56, the mechanism for fixing the movable plates 57 and the locking cylinders 58, the body of which is fixed to the frame of the fixed plate through the bracket 59, and the rod of the pneumatic cylinder is fixed to the frame of the movable plate through the bracket 60. Also, the bottom lifting mechanism 61 is installed on the base 49, tory is fixed to the base bracket 49 and is driven by a pneumatic cylinder.

An upper plate 62 is mounted on top of the fixed plates with bolted joints. A locking and blowing assembly 63 is installed on the upper plate 62, which consists of an arm 64 of the clamp mechanism 65 with blowing heads 66, as well as exhaust pneumatic cylinders 67 and rods 68 for drawing heated preforms under pressure mold 69. In addition to the locking and blowing unit 63, components of the pneumatic system and control 70 (valve and distributor blocks, etc.) are mounted on the top plate 62. A manipulator carriage 71 is attached to the lower plane of the upper plate 62, which consists of locking and transfer elements (grips, transfer and closing drives).

The autoloader 4 is arranged relative to the container 1 in the area of preform entry into the furnace. The relative position of the main elements of the autoloader 4 may vary depending on the process flows and the layout of the workshop.

The hopper 72 of the autoloader 4 consists of a frame 73, a box (hopper) 74, a vibration motor mounted on a spring-loaded platform in the bottom of the box and a photosensor for monitoring the level of the preform. Also on the hopper there is a connecting platform that connects the hopper 72 to the conveyor 75, which is mounted at a certain angle on the frame 76. The conveyor belt 75 moves due to the gear motor 77 installed on the upper shaft.

The orientator 78 consists of a frame 79 and a housing 80, in which two parallel shafts with an angle of inclination from 8 to 20 ° relative to the horizon, guides and a bump 81 are installed. The orientator shafts are rotated by an installed gear motor, which through a chain transmission system provides simultaneous rotation in opposite directions of both shafts. Rotation of the chipper is also carried out from an individual gear motor.

Slider 82 is attached to the body of the orientator 80, which consists of two parallel guides 83 made of an angular profile. An upper clamping bar and two photosensors, which control the level of filling of the slice with a preform, are installed on the slope. To the furnace 2 skliz 82 is attached with brackets.

The automatic blowing machine for PET containers is operating, cited as an example of the use of the invention, as follows.

The bunker 72 is loaded with the preform by any known method: a loader (skip loader SP-0.4) or manually. The preform from the hopper is captured by the blades of the belt conveyor 75 "scraper type", which at a certain angle moves the preform into the orientator 78. This conveyor is driven by a gear motor 77, which has a smooth speed control due to the installed frequency converter. During the operation of the machine, the preform level in the hopper 72 is constantly monitored due to the installed photosensor, which gives a signal if there is no preform in the field of vision. After receiving the signal from the photosensor mounted on the hopper, the controller gives a command to activate the vibration motor, which is installed in the bottom of the hopper on a spring-loaded platform. As a result of the operation of the vibration motor, the hanging preform is shed.

The conveyor 75 dumps the captured preform into the orientator 78, where it falls between two parallel shafts that are installed in the orientator housing at an angle of 8 to 20 ° relative to the horizon. These shafts rotate in opposite directions, thereby preform caught between them is oriented in a vertical position (neck up) and moves down the guide located above the rotating shafts. One of the shafts has the ability to move parallel to the axis of the second shaft to provide clearance adjustment depending on the use of different sizes of preforms. The preform, not oriented on the shafts, falls into the operating zone of the bump 81, which throws it into the upper part of the orientator to provide orientation, i.e. hit the base of the preform between the two shafts. Orientator shafts are rotated by an installed gear motor, which through a chain transmission system provides simultaneous rotation in opposite directions of both shafts. Rotation of the chipper is also carried out from an individual gear motor.

Further, the oriented preform from the guides of the orientator 78 is moved to the slide 82, which provides the feed of the preform from the orientator to the furnace 2. Two photosensors are installed on the slide which control the filling of the slide with the preform. One sensor is located at the bottom of the slope and controls the inclusion of conveyor 2 after the preform enters the field of vision, and the second is installed at the top and controls the stop of the conveyor after filling the preform with the slice.

From the slope, the preform enters the furnace 2, at the entrance to which a cutter 45 and a turnstile 43 are installed to ensure a consistent feed of the preform under the cone 34 of the rotator 33 mounted on the movement mechanism 26. In case of an emergency, the feed of the preform into the furnace can be stopped by the cutter 45 , which can be controlled both manually through management tools, and programmatically. The preform captured by the cones moves along the furnace, where its base is heated uniformly due to 10 halogen incandescent lamps installed in the heating blocks 13. Several lamps are installed in each heating block, the number of which depends on the length of the used preform. On the opposite side relative to the lamps, a reflector 11 is installed having a mirror surface that provides a more efficient distribution of thermal energy. To ensure uniform heating of the preform while moving along the furnace, it rotates around its axis, which is transmitted from the toothed belt 37 to the splined roller 36 installed in the upper part of the axis of the rotator 33. The atmosphere in the heating zone requires constant mixing and selection of hot air, which is provided by the systems boost 21 and air exhaust 17. The boost system 21 pumps air through the louvers of the reflector 11, thereby providing a more efficient heating of the base of the preform. Simultaneous air sampling takes place through the duct 18, located at the bottom of the heating units, which are connected by a common collector to the fan 19. The air injection rate is regulated by a frequency converter, and the air sampling rate is regulated by gates 20.

To prevent overheating of the ends of the lamps, a fan 14 is installed on each heating unit, which pumps air to the places where the lamps 12 are attached.

During the passage of the preform through the furnace 2, its threaded sign and girdle are constantly cooled, since the guides on which the preform girdle rests are made in the form of a collector 25 through which the coolant passes.

At the exit of the furnace, the cone of the rotator 33 is removed from the threaded preform sign. This is due to the fact that a copier having a stepped shape, which is a support for the belt of the cone of the rotator, is installed in the removal zone. When the cone belt hits the copier, it rises relative to the threaded sign of the preform, while the preform is fixed with its belt in the groove under the copier, thereby ensuring that the rotator cone is removed from the heated preform. After removing the cone, the rotators 33 on the chain 31 of the mechanism for moving the preforms 26 rise up, where the cooling box 38 of the circuit 31 is located, along which the cooled air is pumped through the heat exchanger 39 by the fan 40.

After removal, the heated preform is sequentially picked up by the comb mechanism 46 and aligned in a row at a certain distance. The number of preforms displayed is a multiple of the number of bottles blown per cycle.

After setting the required number of preforms in the zone of comb 46, a cycle of automatic blowing of products starts in the following order.

1. The blowing cycle is started by a signal from the photosensor at the output of the comb unit 46, plus a signal from the “End of danger zone” sensor on the comb from the power side.

2. With the simultaneous presence of the two above signals, the grips of the manipulator carriage 71 are triggered, i.e. the grippers are closed and they hold the heated preforms in the area of the threaded sign and at the same time hold the blown bottles in the mold 69.

3. After the sensor "Capture is closed", the movement of the carriage 71 from the furnace to the power plant begins.

4. When the sensor "Carriage in front" is activated, the bottom of the mold 61 rises.

5. After the sensor "bottom above", the mold 69 is closed.

6. After the sensors "Mold is closed", the grips of the manipulator carriage 71 are opened. At the same time, the locks of the locking mechanism of the movable plates 57 are lifted and the inflatable heads 66 and exhaust rods 68 of the locking and inflation unit 63 begin to lower.

7. After the “Capture open” sensor has been triggered, the carriage 71 returns to its original position (after the next batch of heated preforms), respectively, the remote captures of the carriage 71 approach the mold 69.

8. When the exhaust rods 68 move down, the “Rod up” sensor is turned off and the “Rod down” sensor is triggered.

9. The valves 70 of the preliminary blowing and filling of the power cylinders 52 of holding the molds during the preliminary blowing, which operate until the sensor "Rod below" is opened, open. In this case, the product is preliminarily inflated and the molds 69 are retained from opening by the power cylinders 52 at a pressure of 1.0-1.6 MPa. The existing program allows the inclusion of these valves 70 on the timer.

10. When the sensor "Rod below" is triggered, the valves of the main blowing 70 and filling of the power cylinders 52 of the mold holding during blowing are turned on, after which the products are filled and the molds 69 are kept from opening by the power cylinders 52 with high pressure air up to 4.0 MPa. The existing program allows the inclusion of these valves on a timer.

Both the preliminary and the main blowing have a lock in case of untimely lifting of the locks of the mold 69, in order to prevent breakage of the mechanisms for fixing the mold 57.

11. At the end of blowing, the air vent valve 70 from the product opens until the reset timer is completed.

12. At the end of the discharge, the inflatable heads 66 and exhaust rods 68 are returned to their original position, and the locks of the locking mechanism 57 are lowered.

13. The moment of raising the rods 68 up completes the first blowing cycle. Further, the controller expects the next operation of two sensors - see paragraph 1

14. After completing paragraph 2 of the blowing cycle, the mold 69 is opened by a signal from the “Capture Closed” sensor, while the blown products are simultaneously held in the mold zone and heated preforms in the comb zone 46.

15. By the signals of the sensors “Form is open” the bottom of the mold 61 is lowered.

16. At the same command, the carriage begins to move from the furnace to the power.

17. Then the cycle continues in order starting from point 4 of the blowing cycle.

So, it is obvious that, in contrast to the prototype, the locking mechanism 3 of the molds (power unit), consisting of two fixed plates 50 containing frames 51, power cylinders 52 and stops 53, and movable plates 54 containing frames located between the fixed plates 50 56, the locking mechanisms of the movable plates 57 and the locking cylinders 58, the housing of which is fixed to the frame of the fixed plate through the bracket 59, allows to obtain a different, non-obvious technical result. Namely, the creation of a backpressure that excludes the longitudinal opening of the molds at the time of blowing out the PET containers, which is created due to the lateral fixation of the stops 53 between the movable plates 54 with fixed half-molds and power cylinders 52, which at the time of filling the molds with high-pressure air up to 4.0 MPa carry retention of the movable plates 54 from disclosure. In the prototype, the locking mechanism of the molds is used to ensure parallelism of the locked and fixed molds.

Claims (1)

An automatic machine for blowing out PET containers, including a conveyor for moving the workpieces — an auto-loader, a heating device — an oven, a mechanism for blowing out PET containers, a locking mechanism for molds — a power unit, characterized in that the mechanism for locking the molds — a power plant — is located inside the container and consists of two fixed plates containing frames, power cylinders and stops, and located between the fixed plates of moving plates containing frames, locking mechanisms of movable plates and closing cylinders, the body of which is fixed to the frame a fixed plate through the bracket, in this case, when PET containers are blown out with high pressure air from the heated preform, counterpressure occurs, which excludes the longitudinal opening of the molds at the time of blowing out the PET containers, which is created due to lateral fixation of stops between movable plates with fixed half-molds and power cylinders which, at the time of filling the molds with high pressure air up to 4.0 MPa, hold the movable plates from opening.

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