WO2014129988A1

WO2014129988A1 - Air cooled polystyrene injection molding machine with multiple movable molds

Info

Publication number: WO2014129988A1
Application number: PCT/TR2014/000022
Authority: WO
Inventors: Umut Akkaya
Original assignee: Akkaya Eps Maki̇na İmalat Sanayi̇ Ve Ti̇caret Anoni̇m Şi̇rketi̇
Priority date: 2013-02-20
Filing date: 2014-01-29
Publication date: 2014-08-28

Abstract

Air cooled injection moulding machine (1) realizing the production of thin walled products such as decorative ceiling tiles, lamp centres and the like, comprising: at least one movable mould (80) capable of moving on the mould moving paths (73) arranged inside the machine body (2) at the top and bottom portions thereof; a filling station (10); a steam station (20) disposed adjacent to said filling station (10) and providing steam into the movable mould (80); a cooling station (30) cooling the material being filled into the movable mould (80) by blowing air; a discharge station (40) enabling the product with completed production process to be removed from the movable moulds (80); a double deck band unit (70) enabling the multiple movable moulds (80) to be advanced inside the machine body (2) so as to form a loop between the filling station (10), steam station (20), cooling station (30) and discharge station (40); a mould lowering lift (50) and a mould raising lift (60).

Description

DESCRIPTION

AIR COOLED POLYSTYRENE INJECTION MOLDING MACHINE WITH MULTIPLE MOVABLE MOLDS

TECHNICAL FIELD

The present invention relates to an injection molding machine used in the production of thin walled products such as decorative ceiling tiles, lamp centers and the like from a thermoplastic material referred to as expanded polystyrene rigid foam (EPS).

In particular, the present invention relates to a compact injection molding machine having, thanks to the multiple and movable mold mechanism comprised therein, a high rate of production, an easy mold changing feature, being cooled with air without the need for mold cooling water and vacuuming processes and consuming less energy than the existing systems.

PRIOR ART

In the prior art, expanded polystyrene rigid foam (EPS) is typically a white thermoplastic material in the form of a foam with closed cells derived from petroleum by means of polymerization of styrene monomer. In special productions, products of particles processed so as to reflect the long wave radiation are available in gray/black shades.

In the EPS products obtained by inflating and incorporating the polystyrene particles, pentane is the blowing gas used for inflating the particles and obtaining foam. After pentane, an organic compound, leads to the formation of a large number of small pores in the particles, it is replaced by air during and following the production in a very short period of time. The released pentane gas is converted into C0₂ and water vapor (H₂0) being already present in the atmosphere. Still air is trapped inside the large number of small pore closed cells comprised in the material (3-6 billion in 1 m³ of EPS depending on the density) upon releasing of pentane. 98% of the material is still air and the remaining 2% is polystyrene.

After the material is obtained as raw material in the form of small particles, it is subjected to pre-expansion process. Meanwhile, pentane gas inside the particles is replaced with air and desired density of the material is substantially obtained at this stage. Then, incorporation of the expanded particles being kept in the hoppers is provided inside the mold by means of water vapor and characteristics are conferred to the material. A continuous mass with a honeycomb appearance formed by fused polygons without any gaps therebetween emerges as a result of the fusion of the particles with one another. The subsequent production steps vary according to the area of use of the material.

The expandable polystyrene (EPS), mainly used as a material for thermal insulation and packaging, is also used in the production of decorative ceiling tiles and lamp centers. The existing machines in this sector operate with a single and fixed molding system. In the production technique, mold cooling water and vacuuming are used.

In the existing production systems, there are various disadvantages associated with the use of single and fixed molding systems and performing the cooling with water. Some of these disadvantages are as follows:

• Longer duration of mold change and inflexibility in production resulting from the use of single and fixed molds in the production;

• High cost of large single piece molds;

· Increased energy consumption due to the withdrawal by vacuuming of water used in the production for cooling the mold and the utilization of hydraulic machines in the production;

• Certain amount of investment in infrastructure being made for cooling water and vacuuming; and

· Enlargement of the machine size for obtaining more cells.

Consequently, injection molding machines for producing decorative ceiling tiles and lamp centers from polystyrene rigid foam are improved; thus, new structures which would eliminate the aforementioned drawbacks and offer solutions to the existing systems are needed. OBJECT OF THE INVENTION

The present invention relates to an injection molding machine, which meets the aforementioned requirements, eliminates all the drawbacks, and provides additional advantages.

An object of the present invention is to introduce a new injection molding machine capable of performing the production of decorative ceiling tiles and lamp centers from expandable polystyrene material with multiple and movable mold mechanism into the art.

Another object of the present invention is to reduce the infrastructure investment costs as well as production costs by simplifying the production technique of the injection molding production using polystyrene material.

Another object of the present invention is to shorten the mold change duration and enable production of different types of products (production flexibility) to be carried out thanks to the multiple and movable mold system.

Still another object of the present invention is to reduce the mold cost for each different type of products as compared to that of the normal production.

Shortening the duration of the production is intended thanks to the mold cooling water and vacuum free production processes.

Another object of the present invention is to reduce the production costs thanks to the lack of mold cooling water and vacuuming processes in the production technique.

Reducing the costs of the initial investment is intended by excluding the equipment required for mold cooling water and vacuuming processes thanks to the simpler air cooling system. Another object of the present invention is to reduce the size of the machine, thereby, providing space savings in the production site, thanks to a multi-mode and compact structure with a multiple and movable mold system moving in the top and bottom portions.

Another object of the present invention is to use an electric drive system instead of the hydraulic drive system in the production technique, thereby reducing energy consumption. Simultaneous progress of three different production stages by means of a single movement mechanism is intended.

Another object of the present invention is to increase the production rate and capacity of the injection molding machine used in the production of decorative ceiling tiles and lamp centers from polystyrene material and to reduce the production costs thereof.

The present invention, in order to achieve all the objects mentioned above and to be understood from the following detailed description, relates to an air cooled injection molding machine realizing the production of thin walled products such as decorative ceiling tiles, lamp bases and the like with a closed loop movement system in a sequential and rapid manner by filling thermoplastic materials such as expandable polystyrene, etc. from a filling station into the multiple and movable molds moving inside a carrier body. Said injection molding machine comprises the following:

• at least one movable mold capable of moving on the mold moving paths arranged inside the machine body at the top and bottom portions thereof;

• a filling station enabling the material used in the production to be transferred from a raw material receptacle into said movable mold;

• a steam station disposed adjacent to said filling station and providing steam into the movable mold;

• a cooling station cooling the material being filled into the movable mold by blowing air; • a discharge station enabling the product with completed production process to be removed from the movable molds;

• a double deck band unit enabling the multiple movable molds to be advanced inside the machine body so as to form a loop between the filling station, steam station, cooling station and discharge station;

• a mold lowering lift enabling the movable mold moving in the upper portion of said double deck band unit to be lowered to the lower deck; and

• a mold raising lift enabling the movable mold moving in the lower portion of said double deck band unit to be raised to the upper deck.

The structural and the characteristic features and all advantages of the present invention will be understood more clearly with the following figures and the detailed description written by referring to said figures; therefore, the evaluation needs to be done by taking said figures and the detailed description into consideration.

BRIEF DESCRIPTION OF THE FIGURES

Embodiment of the present invention and advantages thereof with the additional components must be considered together with the figures explained below in order to be fully understood.

Figure 1 : A three-dimensional front view of the injection molding machine according to the present invention.

Figure 2 : A three-dimensional rear view of the injection molding machine according to the present invention.

Figure 3 : A side view of the injection molding machine according to the present invention.

Figure 4 : Three-dimensional views from various angles of a preferred embodiment of the movable mold of the injection molding machine according to the present invention used in the production.

REFERENCE NUMERALS

1. Injection molding machine 2. Machine body

3. Raw material receptacle

10. Filling station

11. Upper body

12. Body mounting legs

13. Drive transmission rod

14. Filling injector

20. Steam station

21. Driving element

22. Steam room

23. Threaded shafts

30. Cooling station

31. Cooling fan

32. Cooling compartment

40. Discharge station

41. Driving element

42. Drive transmission rod

43. Mold opening apparatus

44. Product removal suction cups 45. Arrangement section

46. Suction cup piston

47. Filling tube blower

50. Mold lowering lift

51. Mold fixing piston

60. Mold raising lift

61. Mold fixing piston

70. Band unit

71. Driving element

72. Mold moving lever

73. Mold moving path

80. Movable mold

81. Car mechanism

82. Wheels

83. Filling hole 84. Steam holes

85. Mold body

86. Mold cover DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, preferred embodiments of the injection molding machine (1) according to the present invention are described only for a better understanding of the subject, without constituting any restrictive effect.

The present invention relates to an injection molding machine (1) used in the production of thin walled products such as decorative ceiling tiles, lamp centers and the like from a thermoplastic material referred to as expanded polystyrene rigid foam (EPS). In Figure 1 , a three-dimensional front view of the injection molding machine (1) according to the present invention is given. Accordingly, said injection molding machine (1) has a rectangular prismatic body (2) formed by horizontally and vertically by joining the metal carrying profiles. The mechanisms enabling the realization of the production in the injection molding machine (1) are disposed in said body (2).

The injection molding machine (1) according to the present invention primarily comprises the following: a filling station (10); a steam station (20); a cooling station (30); a discharge station (40); mold lowering (50) and raising (60) lifts; and a band unit (70) adapted inside the machine body (2). In Figure 2, a three-dimensional rear view of the injection molding machine (1) according to the present invention is given.

As can be seen in Figure 1 and Figure 2, the filling station (10) and the steam station (20) are disposed in the middle upper portion of the machine body (2) in the form of a rectangular prism. For these two stations (10, 20), the cooling station (30) is located next to the steam station (20) and the discharge station (40) is located next to the filling station. The mold lowering lift (50) and the mold raising lift (60) are located at both ends of the machine body (2). Said lifts (50, 60) are connected with a band unit (70) rotating the movable product mold inside the machine body (2) from the top portion to the bottom portion and vice versa. In Figure 3, a side view of the injection molding machine (1) according to the present invention is given. In this figure, all the operation stations (10, 20, 30, 40) disposed on the machine body (2), the band unit (70) and lift structures (50, 60) can be seen from the side profile. In the injection molding machine (1) according to the present invention, the filling station (10) is connected to the raw material receptacle (3) mounted to the machine body (2) by means of a long profile at a high level. Expandable polystyrene material is stored in said raw material receptacle (3). The upper body (1 1) roughly in the form of an X is located in the upper portion of the filling station (10). The upper body (11) is mounted to the machine body (3) by means of four body mounting legs (12). Said legs (12) provide the sufficient height to the upper body (1 1) in the form of an X so as to enable to move under the movable mold (80) and above the band unit (70). A filling injector (14) is disposed in the middle portion of the upper body (11). Said filling injector (14) enables the thermoplastic material disposed inside the raw material receptacle (3) to be transferred into the movable mold (80).

The station after the filling station (10) is the steam station (20). Steam is provided to the steam holes (84) disposed on the movable mold (80) by means of a steam room (22) disposed in said steam station (20). The steam room (22) is moved up and down by means of a driving element (21) connected thereto. Said driving element (21) is preferably an electric powered servo motor. Threaded shafts (23) are disposed at each corner of the rectangular form steam room (22). Said threaded shafts (23) are moved up and down by the driving element (servo motor) (21). Thus, the steam room (22) disposed on the shafts (23) are also moved up and down.

In the injection molding machine (1) according to the present invention, the station after the steam station (20) is the cooling station (30). The mold cooling fan (31) enabling the mold (80) to be cooled while moving on the band unit (70) is disposed in said cooling station (30). In this station (30), the movable mold (80) passes through a cooling compartment (32) with air blown therein by a cooling fan (31).

The station after the cooling station (30) is the discharge station (40). A mold opening apparatus (43) enabling the mold cover to be opened for removing the finished product from the mold (80) is disposed in the discharge station (40). The movement of said mold opening apparatus (43) is provided by a driving element (41) connected thereto. The driving element (41) is preferably an electric powered servo motor. After the mold (80) is opened by means of the mold opening apparatus (43), the removal of the product from the mold (80) is carried out by means of the product removal suction cups (44). Said suction cups (44) are moved up and down by means of a piston (46) connected thereto. The suction cups (44) adhere to the product, pull it upwards from the mold (80) and transfer it to the arrangement section (45). The arrangement section (45) is a rail platform extending outwardly from the machine body (3). The removal suction cups (44) move on said rail platform (45) and enable the product to be removed by the operator. A filling tube blower (47) disposed in the discharge station (40) transfers the material used in the production to the raw material receptacle (3).

In the injection molding machine (1) according to the present invention, a multiple mold system is used. 9 movable molds (80) can be simultaneously processed on the machine body. The production can be performed for a single product, as well as simultaneous production of different products using different molds (80). In Figure 4, three-dimensional views from various angles of a preferred embodiment of the movable mold (80) used in the production are given. Accordingly, the movable mold principally comprises a rectangular body (85) and a mold cover (86) enclosing said body (85). The mold is filled through a hole (83) disposed in the upper middle portion of the mold cover (86). The fluid raw material flowing through the channels disposed in the mold (80) takes the form of the product. Car mechanisms (81) are mounted on the two opposite sides of the mold (80). Said car mechanisms (81) are provided with wheels (82). Said structure provides moving ability to the mold (80).

In the injection molding machine (1) according to the present invention, the movable molds (80) comprising cars (81) with wheels (82) move on a double deck band unit (70). Said band unit (70) comprises a mold moving path (73) with two decks on top of each other passing through the filling (10), steam (20), cooling (30) and discharge (40) units from the top portion to the bottom portion and vice versa. The movable molds (80) can move on the mold moving path (73) sort of a rail system thanks to the car mechanisms (81) with wheels (82). The movement of the molds (80) is provided by a driving element (71) mounted to the machine body (2). Said driving element (71) is preferably an electric powered servo motor. The connection between the driving element (71) and the molds (80) is achieved by means of a mold moving lever (72). The mold moving lever (72) moves the mold (80) on the mold moving path (73) by directing the movement that it receives from the driving element (71).

Lift mechanisms (50, 60) are provided at both ends of the band unit (70). These are the mold lowering lift (50) and the mold raising lift (60). The function of the mold lowering lift (50) is to enable the mold (80) moving on the upper mold path (73) to be taken to the lower mold path (73) at the end of the band unit (70), while the function of the mold raising lift (60) is to enable the mold (80) moving on the lower mold path (73) to be taken to the upper mold path (73) at the end of the band unit (70). Thus, the movable mold (80) is enabled to make a loop inside the machine body (2). The multiple molds (80) processed at the stations (10, 20, 30, 40) disposed in the machine body (3) move in series and regularly during this loop. Mold fixing pistons (51 , 61) enabling fixing the movable molds (80) during the up and down transportation thereof are disposed in the mold lowering lift (50) as well as the mold raising lift (60).

Operating principle of the injection molding machine (1) according to the present invention used in the production of thin walled products such as decorative ceiling tiles, lamp centers and the like is as follows:

First, the molds (80) of the products to be produced are placed on the machine body (2). These molds (80) can belong to the same types of products; besides, molds (80) for different kinds of products can also be used. Different products can be produced at the same time. After the movable molds (80) are placed, the production data is entered from the control panel into the injection molding machine (1) and start command thereto is issued. In the filling station (10), expandable polystyrene material is transferred from the raw material receptacle (3) into the mold (80) disposed below the upper body (11) by means of the filling injector (14). After sufficient amount of material is transferred, the mold (10) is conveyed to the subsequent steam station (20) by means of the drive transmission rod (13). The movable mold (80) enters into the steam room (22) and the steam room (22) descends onto the mold (80) by means of the threaded shafts (23) driven by a servo motor (21) and steam is applied into the mold (80) through the steam holes (84) disposed on the mold (80). After the operation is completed, the steam room (22) ascends and the movable mold (80) reaches the mold lowering lift (50) by advancing of the mold moving path (73). In the lift (50), the movable mold (80) is first fixed by the mold fixing pistons (51) and then the mold (80) is lowered down. The movable mold (80) being lowered to the mold moving path (73) on the lower deck advances to the cooling station (30) and enters into the cooling compartment (32) disposed in the cooling station (30). In this section, the mold (80) is cooled by means of the air blown by the cooling fan (31).

After the cooling operation, the movable mold (80) continues to advance on the lower mold moving path (73) and reaches the mold raising lift (60) disposed at the end of the double deck band unit (70). Here, the movable mold (80) is first fixed by the mold fixing pistons (61) and then the movable mold (80) is transferred to the mold moving path (73) provided in the upper part of the double deck band unit (70) by the mold raising lift (60). The movable mold (80) advancing on the mold moving path (73) in the upper portion enters into the discharge station (40) disposed herein. The mold (80) entering the discharge station (40) is first intervened by the mold opening apparatus (43). The mold opening apparatus (43) moved by means of a driving element (41) descends onto the mold (80) and opens the mold cover (86) thereof and then lifts the cover (86) upwards. At this stage, product removal suction cups (44) are activated. The suction cups (44) moves over the product disposed inside the movable mold (80), lowered down by means of the pistons (46) and stick to the product. Then, the suction cups (44) stuck to the product are again moved upwards by means of the pistons (46), thereby removing the product from the mold (80). The product removal suction cups (44) advance towards the arrangement section (45) and the final product is packaged after being taken outside the machine (1) by the operator. Then, the movable mold (80) advances and reaches again the starting point, i.e. the filling station (10). The process described above continues as a loop with 9 movable molds (80).

Thanks to the present invention, a new injection molding machine (1) capable of performing the production of thin walled products such as decorative ceiling tiles, lamp centers and the like from expandable polystyrene material with multiple and movable mold (80) embodiment is introduced into the art. The mold cooling water and vacuuming processes of said water are excluded from the art; instead, an air cooled system is employed. In this regard, the machine is designed as a simpler structure and the initial investment costs are reduced. The mold (80) change duration is shortened thanks to the multiple and movable mold system. It is possible to produce different types of products by simultaneously placing different molds inside the machine body (2). In this regard, production speed and flexibility are provided. Duration of the production is shortened and production costs are reduced thanks to production technique free of the mold cooling water and vacuuming processes. In the production performed with the injection molding machine (1) according to the present invention, a multi-mode and compact structure is obtained by the multiple and movable mold system moving in the top and bottom portions. Thus, reducing the size of the machine and providing space savings in the production site are made possible. In addition, energy consumption is reduced by using an electric drive system instead of the hydraulic drive system in the production technique. Briefly, the production rate and capacity of the injection molding machine (1) used in the production of decorative ceiling tiles and lamp centers from polystyrene material are increased, and correspondingly the production costs thereof are reduced.

It is possible to produce products of different sizes and quantities by increasing and decreasing the number and size of the movable molds (80) in the present injection molding machine (1). The production of the products can be carried out by means of smaller and greater number of molds. As an alternative to the servo motors used as the driving element, driving elements operating with pneumatic or hydraulic systems can also be used.

Claims

An air cooled injection molding machine (1) realizing the production of thin walled products such as decorative ceiling tiles, lamp centers and the like with a closed loop movement system in a sequential and rapid manner by filling thermoplastic materials such as expandable polystyrene, etc. from a filling station (10) into multiple and movable molds (80) moving inside a carrier body (2), characterized in comprising the following;

• at least one movable mold (80) capable of moving on mold moving paths (73) arranged inside the machine body (2) at top and bottom portions thereof;

• a filling station (10) enabling the material used in the production to be transferred from a raw material receptacle (3) into said movable mold (80);

• a steam station (20) disposed adjacent to said filling station (10) and providing steam into the movable mold (80);

• a cooling station (30) cooling the material being filled into the movable mold (80) by blowing air;

• a discharge station (40) enabling the product with completed production process to be removed from the movable molds (80);

• a double deck band unit (70) enabling the multiple movable molds (80) to be advanced inside the machine body

(2) so as to form a loop between the filling station (10), steam station (20), cooling station (30) and discharge station (40);

• a mold lowering lift (50) enabling the movable mold (80) moving in the upper portion of said double deck band unit (70) to be lowered to the lower deck;

• a mold raising lift (60) enabling the movable mold (80) moving in the lower portion of said double deck band unit (70) to be raised to the upper deck.

The injection molding machine (1) according to claim 1 , characterized in comprising a car mechanism (81) mounted on two opposite sides of the movable mold (80) and enabling the movement of the mold (80) on the band unit (70).

3. The injection molding machine (1) according to claim 2, characterized in comprising the car mechanism (81) enabling the movement of the movable mold (80) on the band unit (70) preferably comprises wheels (82).

4. The injection molding machine (1) according to claim 1 , characterized in comprising at least one mold cooling fan (31) cooling the movable mold (80) by blowing air thereto while moving in the cooling station (30).

5. The injection molding machine (1) according to claim 1 , characterized in comprising a mold cooling compartment (32) directing the air blown by the cooling fan (31) onto the movable mold (80) while said movable mold (80) passes through the cooling unit (30).

6. The injection molding machine (1) according to claim 1 , characterized in comprising at least one mold fixing piston (51) securing the movable mold (80) for descending movement in the mold lowering lift (50).

7. The injection molding machine (1) according to claim 1 , characterized in comprising at least one mold fixing piston (61) securing the movable mold (80) for ascending movement in the mold raising lift (60).

8. The injection molding machine (1) according to claim 1 , characterized in comprising mold moving paths (73) provided on the double deck band unit (70) disposed inside the machine body (2) on which the movable molds (80) advance by means of the successive car mechanisms (81).

9. The injection molding machine (1) according to claim 1 , characterized in comprising at least one driving element (21) disposed in the steam station (20) and moving the steam room (22) up and down.

10. The injection molding machine (1) according to claims 1 and 9, characterized in that the driving element (21) disposed in the steam station (20) and moving the steam room (22) up and down is preferably an electric powered servo motor.

11. The injection molding machine (1) according to claims 1 and 9, characterized in comprising at least one driving element (71) providing the required driving for the movement of the multiple molds (80) on the double deck band unit (70).

12. The injection molding machine (1) according to claims 1 to 11 , characterized in that the driving element (71) providing the required driving for the movement of the multiple molds (80) on the double deck band unit (70) is preferably an electric powered servo motor.

13. The injection molding machine (1) according to claims 1 to 11 , characterized in that comprising a mold moving lever (72) providing the connection between the driving element (71) and the molds (80) and moving the molds (80) on the mold moving path (73) by directing the movement received from the driving element (71).

14. The injection molding machine (1) according to any one of the preceding claims, characterized in that the number of movable molds (80) disposed on the machine body (2) can be increased or decreased by changing the dimensions of the movable molds (80).

15. The injection molding machine (1) according to any one of the preceding claims, characterized in that the number of multiple molds (80) processed simultaneously on the machine body (2) can be increased by changing the length of the machine body (2) together with the band unit (70).

16. The injection molding machine (1) according to any one of the preceding claims, characterized in that molds (80) belonging to different products can be simultaneously used in the loop type production process.