DESC:AN ARMLESS MACHINE FOR BI-AXIAL ROTATIONAL MOULDING

FIELD OF INVENTION

[0001] The present invention generally relates to the field of moulding machines. In particular, the present invention relates to an armless machine for bi-axial rotational moulding that uses a single-motor driving mechanism with a pulley mechanism.

BACKGROUND OF THE INVENTION

[0002] Presently, there are several rotational moulding machines available in the market. The available rotational moulding machines use an arm assembly with a set of bevel gears as a driving mechanism for providing biaxial motion to a mould. For achieving bi-axial motion, two individual motors are used in the available rotational moulding machines. Further, it is observed that in such machines the burner is mounted in a separate burner box above the blowers and the blower is mounted at the bottom. The blower throws hot air into the furnace from the bottom. The blower throws air into the furnace from the bottom to achieve circulation.

[0003] These rotational machines of the prior arts have the disadvantages the arm assembly of the existing mechanisms were heavy as it consisted of a U-shaped metallic arm for holding the mould and involved using two individual motors thereby leading to an increase in the manufacturing cost. Further, the size of the furnace was increased due to additional components/parts inside the furnace thereby leading to more heat consumption, making it cost intensive, increasing the complexity and reducing the energy efficiency of the machine.

[0004] Several attempts are made to design a machine that overcomes the abovementioned problems associated with biaxial moulding. For example:

[0005] CN210233719U discloses a rotational moulding machine for processing hot rotational moulding lining that comprises an opening formed at the top of the operation box; two supporting plates are welded to the bottom of the operation box. The same bottom plate is welded to the bottoms of the two supporting plates. A driving motor is fixedly mounted at the top of the bottom plate; a driving shaft is welded on an output shaft of the driving motor; a plurality of brush blades are fixedly mounted on the outer side of the driving shaft; a mounting cylinder with an opening in the top is contacted with the bottom inner wall of the operation box; a vertical hole is formed in the inner wall of the bottom of the mounting cylinder, a shaft hole is formed in the bottom of the operation box, the driving shaft is rotationally mounted in the shaft hole, the top end of the driving shaft penetrates through the vertical hole, multiple flanges are placed in the mounting cylinder, a screw cap is mounted at an opening of the mounting cylinder through threads, and a through hole is formed in the top end of the screw cap. The flange coating device is good in practicability, capable of automatically coating the inner surface of a flange, high in efficiency and capable of achieving uniform coating.

[0006] CN104908183A discloses a rotational moulding machine that relates to a rotational moulding machine. The rotational moulding machine comprises a base, a support rod, a frame, a heat-preserving furnace and a heating system. One end of the support rod is connected to the base and the other end of the support rod is connected to the frame. The heat-preserving furnace is a hollow furnace and two ends of the furnace are respectively fixed to the frame. The heating system is located at the inner side of the heat-preserving furnace and comprises a power supply and an electrothermal conduit. The electrothermal conduit is filled with heating wires.

[0007] Although there are a number of solutions in the form of rotational moulding machines, none of them is specially designed without arm assembly. Although some of the prior existing solutions attempt to create reliable and economical rotational moulding machines, this solution fails to meet the user’s requirement. In view of the above prior art, it can be understood that many rotational moulding machines have been designed in an attempt to provide a similar solution, however, they are bulky, expensive, and inefficient.

[0008] Therefore, there exists a need in the art for providing a bi-axial rotational machine that overcomes the abovementioned drawbacks of the prior arts.

OBJECTS OF THE INVENTION

[0009] An object of the present invention is to provide an armless machine for bi-axial rotational moulding, wherein the machine is economical and energy efficient as compared to the available machines.

[0010] Another object of the present invention is to provide an armless machine for bi-axial rotational moulding that is lightweight and compact when compared to the available machines.

[0011] Another object of the present invention is to provide an armless machine for bi-axial rotational moulding that takes less time and fuel to heat and cool the furnace.

SUMMARY OF THE INVENTION

[0012] The summary is provided to introduce aspects related to an armless machine for bi-axial rotational moulding and the aspects are further described below in the detailed description. This summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining or limiting the scope of the claimed subject matter.

[0013] In a preferred embodiment, the present invention provides an armless machine for bi-axial rotational moulding, comprising of an insulated heating chamber, said chamber having one or more walls forming a closed chamber; a pair of supporting frames suitably mounted on the wall of said insulated heating chamber, said supporting frames having a first frame mounted opposite to a second frame; a rotatable mould mounting frame supported by rollers on said supporting frames, said mould mounting frame includes at least one driven belt on the outer circumference of said mould mounting frame. at least two idler pulleys mounted on one frame, said idler pulley engages the driven belt on the mould mounting frame; a rotating pulley mounted on the said one frame, said rotating pulley engages the idler pulley and the driven belt on the mould mounting frame; a motor and gearbox drive coupled to the supporting frames and the said rotating pulley, said motor is operable to: rotatably drive the supporting frames thereby rotating the mould mounting frame in x-direction; rotatably drive the idler pulley thereby rotating the mould mounting frame in y-direction; wherein the motor and gearbox drive provides controllable bi-axial rotation to the mould mounting frame to provide mounted mould the same rotation enabling rotational moulding process to form the product.

[0014] In an embodiment, the pulley is an idler pulley and comprises a driving belt bearing surface.

[0015] In a further embodiment, the first supporting frame and the second supporting frame each include atleast 2 rollers.

[0016] In a further embodiment, the machine further comprise a rotating pulley comprises a driving belt bearing surface. The rotating pulley is a fixed pulley and imparts rotation to the idler pully.

[0017] In yet another embodiment, the driven belt on the mould mounting frame is a spring-embedded belt, which engages the idler pully and the rotating fixed pulley mounted on the supporting frame.

[0018] In yet another embodiment, the supporting frame includes a belt tensioning bracket, to provide necessary tension to the belt.

[0019] In another embodiment, the machine comprises a motor drive which is a single motor drive. The motor causes driving of the belt over the rotating pulley and the idler pulley.

[0020] In an embodiment, the supporting frames are rotatably mounted to the wall of the chamber through a bearing housing.

[0021] In a further embodiment, the walls of the closed chamber provides efficient air circulation within the chamber around the mould.

[0022] In yet another embodiment, the machine further embodied with a burner, said burner is positioned to blow hot air such that hot air is circulated within the closed chamber around the mould. The burner and the chamber together form a furnace for the moulding process. Further, a blower is mounted on the center-top of the chamber, the suction of blower is oriented such that its suction takes air in from the top centre of the furnace and forces air along the walls of the chamber so as to enable efficient cooling and heating of the mould.

[0023] In a preferred embodiment, the walls of the chamber are curved in shape.

[0024] In a further embodiment, the machine further comprises a drive gearbox for controlling the speed of rotation of the motor.

[0025] In yet another embodiment, the chamber provides atleast a first door and a second door, both first and second door located opposite to each other to provide direct air circulation. The first door has a first cavity for feeding the moulding material and the first door has a second cavity for inspection of process.

[0026] In a preferred embodiment, the supporting frame are made of light weight material. The supporting frames can have varying shapes and size to accommodate different size of moulds. Further, the mould mounting frames can have varying shapes and to accommodate different size and quantities of moulds.

[0027] Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings constitute a part of the description and are used to provide further understanding of the present invention. Such accompanying drawings illustrate the embodiments of the present invention which are used to describe the principles of the present invention. The embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this invention are not necessarily made to the same embodiment, and they mean at least one. In the accompanying drawings:

[0029] Fig. 1 illustrates a top view of illustrating the left-hand side arm, a right-hand side arm, single motor driving mechanism and a pulley mechanism of the armless machine for bi-axial rotational moulding in accordance with an embodiment of the present invention.

[0030] Fig. 2 illustrates an enlarged view of the pulley mechanism, as depicted in figure 1.

[0031] Fig. 3 illustrates top view illustrating the supporting frames and rotatable moulding drum.

[0032] Fig. 4 illustrates top view illustrating the pulley mechanism according to an embodiment of the present invention;

[0033] Fig 5 illustrates perspective view of the moulding machine according to an embodiment of the present invention;

[0034] Fig 6 illustrates side view of the moulding machine according to an embodiment of the present invention;

[0035] Fig 7 illustrates the furnace mechanism according to an embodiment of the present invention;

[0036] Fig 8 illustrates the air circulation within the closed chamber in accordance with the present invention; and

[0037] Fig 9 illustrates the door openings of the closed chamber in accordance with the present invention.

[0038] A more complete understanding of the present invention and its embodiments thereof may be acquired by referring to the following description and the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION

[0039] The detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced. Each embodiment described in this invention is provided merely as an example or illustration of the present invention, and should not necessarily be construed as preferred or advantageous over other embodiments. The detailed description includes specific details for the purpose of providing a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

[0040] Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “less than,” “approximately” etc. is not limited to the precise value specified. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value.

[0041] The terms “or” and “and/or” as used herein are to be interpreted as inclusive or meaning any one or any combination. Therefore, “A, B or C” or “A, B and/or C” mean “any of the following: A; B; C; A and B; A and C; B and C; A, B and C.” An exception to this definition will occur only when a combination of elements, functions, steps or acts are in some way inherently mutually exclusive.

[0042] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items.

[0043] The basic manufacturing process of moulding includes melting the plastic pellets or granules in the mould and solidifying the melted plastic pellets or granules to form the desired shape. The material is cooled, solidified and afterwards released by opening the two halves of the mould, in general. This is achieved by bi-axial rotation of mould drum once the pellets or granules are fed into the drum. The present invention provides an armless machine for bi-axial rotational moulting, which is light weight, compact and is efficient as explained hereinafter.

[0044] Fig. 1 illustrates a top-view of the armless machine (1) for bi-axial rotational moulding. The machine comprises a chamber/housing (2) formed by side walls thereby forming a closed chamber. The closed chamber provides a heating chamber in which the mould is prepared. As illustrated, a pair of supporting frames (3, 3’) are suitably mounted on the wall of said insulated heating chamber (2).

[0045] The supporting frames (3, 3’) is provided of suitable material which is light weight, so as to make the overall machine light weight and compact. The supporting frames (3, 3’) are typically constructed from lightweight yet strong material such as advanced aluminum alloys, or any other material suitable for molding applications. These materials are chosen to withstand the temperatures during the heating of the mould while minimizing the weight.

[0046] The supporting frames (3, 3’) are mounted on the wall of the chamber (2) though a bearing housing (11). The pair of supporting frames includes a first frame (3) and a second frame (3’), said first and said second frame mounted opposite to each other on the wall of the chamber (2). The central space between the first frame (3) and the second frame (3’) provides for mounting a rotatable mould mounting frame (4) which is supported by said frames. The supporting frames are sized and shaped to support a rotatable mould mounting frame (4), said rotatable mould is used for processing the pellets or granules.

[0047] The rotatable mould mounting frame (4) is supported by the supporting frames (3, 3’). In one embodiment, the rotatable mould mounting frame (4) is supported by rollers on supporting frames. The rotatable mould mounting frame (4) comprises atleast one belt (5) on the outer circumference of said frame. Said belt provides for a driven belt (5) which facilitates rotation of the rotatable mould mounting frame (4) around its axis. In an embodiment, the driven belt (5) on the mould mounting frame (4) is a spring-embedded belt.

[0048] The mould mounting frame (4) may embody a mould drum which can have various different shapes and sizes depending upon the product that is to be manufactured side. The mould drum is meticulously designed to have a specific geometry and profile to align with the type of product to be manufactured. In an exemplary embodiment, the shape of the mould drum is not limited to the cylindrical shape and may be engineered to change as per the requirements.

[0049] In an embodiment, the mould mounting frames (4) can have varying shapes and to accommodate different size and quantities of moulds.

[0050] In an embodiment, the supporting frames includes a pulley mechanism including a pair of idle pulley (6) and a rotatable pulley (7), which engages with the driven belt (5) of the rotatable mould mounting frame (4) to provide the rotation. The pulley mechanism provided on the supporting frame is explained herein after in more detail.

[0051] Figure 2 illustrates a top view and perspective view of the pulley mounted on the supporting frame. Each of the first and second mounting frame is mounted with idler pulleys (6) as illustrated. The idler pulley (6) includes a belt bearing surface. As illustrated, each of the first and second mounting frame is provided with two idler pulleys (6) on each side.

[0052] Figure 3 illustrates the top view of pulley system provided on the supporting frame. As illustrated, the supporting frames (3, 3’) is further provided with a rotatable pulley (7), which drives the idler pulley (6) by way of tensioning of belt. A driving belt is provided over the belt bearing surface of rotatable pulley (7) and the pair of idler pulleys (6) in such a manner that the rotation of rotatable pulley (7) drives the idler pulleys (6). In an embodiment, a belt tensioning bracket (10) is provided over the supporting frame as illustrated in figure 4, which may adjust the tension on the belt (5) which revolves arounds the rotatable pulley (7) and the pair of idler pulleys (6).

[0053] Figure 5 illustrates a view of the moulding machine in accordance with an embodiment of the present invention. In an embodiment, the idler pulleys (6) engage the spring embedded belt (5) on the rotatable moulding frame (4). The rotatable pulley (7) is coupled to a motor drive, which facilitates controllable rotation of the rotatable pulley. The rotation of the rotatable pulley imparts rotation to the idler pulley (6) by way of tensioning belt. As the idler pulleys rotates, it imparts rotation to the rotatable moulding frame (4) as the idler pulleys (6) are engaged with the spring-loaded belt on the outer circumference of the rotatable moulding frame (4).

[0054] In a further embodiment, each of the first and second supporting frame includes a pair of idler pulleys (6) mounted thereon and each of the first and second supporting frame includes a rotatable pulley (7). In this way, the idler pulleys (6) engage with the spring embedded belt on the mounting frame (4) from both sides, thereby providing controllable and efficient rotation of the rotatable mould mounting frame.

[0055] Further, the first and second supporting frame is coupled to wall through a bearing housing (11), which enable rotation of the first and second supporting frame with respect to chamber wall, when driven by the motor (8).

[0056] The present invention provides an advantage over the state of the art, in that the rotation of the supporting frames (3, 3’), i.e., the first and the second supporting frames and the rotation of the rotatable pulley on each side of first and second supporting frame is achieved through a single motor (8). In an embodiment, a drive gearbox (9) is provided for controlling the speed of rotation of the motor (8).

[0057] In a further embodiment, the motor (8) and gearbox drive (9) is coupled to the supporting frames (3, 3’) and the said rotating pulley (7), such that, when the motor (8) operates, it operates to rotatably drive the supporting frames (3, 3’) thereby rotating the mould mounting frame (4) in x-direction and drive the rotatable pulley (7) and idler pulley (6) thereby rotating the mould mounting frame (4) in y-direction. In this way, the motor (8) and gearbox (9) drive provide controllable bi-axial rotation to the mould mounting frame (4) to provide mounted mould the same rotation enabling rotational moulding process to form the product.

[0058] Figure 6 illustrates top view of the moulding machine in accordance with an embodiment of the present invention. When the rotatable mould frame (4) is rotated inside the chamber (i.e., bi-axially rotated as explained above), it is important to provide heating mechanism inside the chamber so that the granules inside the mould frame melt and achieves the desired shape and characteristics. Also, apart from heating, effective air circulation mechanism (A) is required for effective moulding process.

[0059] The machine of the present disclosure further provides a burner (12) for providing heat to the rotatable moulding frame (4) and a blower (13). In an embodiment, the burner (12) is placed below, on one side to the rotating mould frame (4). When the burner (12) is activated, heat is provided within the closed chamber required for moulding process, wherein the burner (12) and chamber together form a furnace for the moulding process. To make heating uniform within the chamber, a blower (13) is provided at the top center of the machine. The blower is coupled to a drive motor (15) which rotates the blower (13) at the desired speed.

[0060] As illustrated in Fig. 7, the blower (13) and the burner (12) operate such that that burner (12) is positioned to blow hot air and the hot air is circulated within the closed chamber around the mould. The blower mounted on the center-top of the chamber, the suction of blower (13) is oriented such that its suction takes air in from the top center of the furnace and forces air along the walls of the chamber so as to enable efficient cooling and heating of the mould.

[0061] In a preferred embodiment, as illustrated in Fig 8, the walls of the chamber are curved in shape, so that the walls of the closed chamber provides efficient air circulation within the chamber around the mould.

[0062] Once the desired heating and air circulation is achieved, it is essential to provide necessary cooling and air ventilation to facilitate solidification of mould. The present invention provides an efficient solution through the wall of the chamber itself.

[0063] As illustrated in Fig. 9, the chamber (2) may be made of one or more walls, which can be opened. In a particular embodiment, at least two portions of wall opposite to each other (provided by way of a door) can be opened as illustrated, which provides for cross air ventilation over the heated mould, thereby providing efficient cooling and solidification.

[0064] In a further embodiment, atleast the first door (14) and the second door (14’) may comprise a first cavity for feeding the moulding material and a second cavity for inspection of process.

[0065] The present invention provides an armless machine (1) for bi-axial rotational moulding that employs a single motor (8) that rotates the supporting frames (3, 3’)and the pulleys thereby causing the rotation of the mould drum in y-axis and x-axis in a direction perpendicular to each other. The said single motor rotates (8) the mould drum in both the axis y-axis and x-axis at a fixed speed ratio depending upon the product to be manufactured and required speed to be achieved.

[0066] The armless machine (1) for bi-axial rotational moulding of the present invention provides a housing that has no additional components/ parts like a U-shaped and other alike components for rotating the mould drum. This helps in reducing the overall size of the housing and also the manufacturing costs involved therein. Since there is a reduction in the overall size of the housing the heating and cooling of the mould can takes place in a timely and energy efficient manner.

[0067] Particularly, as mentioned in the background section, the moulding machine of the prior arts uses arm assembly which is generally very heavy and make the overall machine immovable from one place. The compact design of the moulding machine according to the present invention enables a person to easily move the machine from one place to another. Also, the operating conditions of the machine enables an ordinary person to afford and set up this moulding machine, which was not possible in prior machines which was generally very complex and required a whole set-up before the machine could be operated.

[0068] The present invention while provides a novel and inventive moulding machine, also adds to the economic significance.

[0069] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any disclosures or of what may be claimed, but rather as descriptions of features specific to particular embodiments of particular disclosures. Certain features that are described herein in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.

[0070] Thus, particular embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results.

[0071] It is to be understood that the disclosure is not to be limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation, unless described otherwise.
,CLAIMS:We Claim:

1. An armless machine (1) for bi-axial rotational moulding, comprising of:
an insulated heating chamber (2), said chamber having one or more walls forming a closed chamber;
a pair of supporting frames (3, 3’) suitably mounted on the wall of said insulated heating chamber (2), said supporting frames having a first frame (3) mounted opposite to a second frame (3’);
a rotatable mould mounting frame (4) supported by rollers on said supporting frames (3, 3’), said mould mounting frame includes at least one driven belt (5) on the outer circumference of said mould mounting frame (4).
at least two idler pulleys (6) mounted on one frame, said idler pulley engages the driven belt (5) on the mould mounting frame (4);
a rotating pulley (7) mounted on the said one frame, said rotating pulley (7) engages the idler pulley (6) and the driven belt (5) on the mould mounting frame (4);
a motor (8) and gearbox drive (9) coupled to the supporting frames (3, 3’) and the said rotating pulley (7), said motor (8) is operable to:
rotatably drive the supporting frames (3, 3’) thereby rotating the mould mounting frame (4) in x-direction;
rotatably drive the idler pulley (6) thereby rotating the mould mounting frame (4) in y-direction;
wherein the motor (8) and gearbox drive (9) provides controllable bi-axial rotation to the mould mounting frame (4) to provide mounted mould the same rotation enabling rotational moulding process to form the product.

2. The machine as claimed in claim 1, wherein the pulley is an idler pulley (6) and comprises a driving belt bearing surface.

3. The machine as claimed in claim 1, wherein the first supporting frame (3) and the second supporting frame (3’) each include atleast 2 rollers.

4. The machine as claimed in claim 1, wherein the rotating pulley (7) comprises a driving belt bearing surface.

5. The machine as claimed in claim 1, wherein the rotating pulley (7) is a fixed pulley and imparts rotation to the idler pully (6).

6. The machine as claimed in claim 1, wherein the driven belt (5) on the mould mounting frame (4) is a spring-embedded belt, which engages the idler pully (6) and the rotating fixed pulley (7) mounted on the supporting frame.

7. The machine as claimed in claim 1, wherein the supporting frame includes a belt tensioning bracket (10), to provide necessary tension to the belt (5).

8. The machine as claimed in claim 1, wherein the motor drive is a single motor drive (8).

9. The machine as claimed in claim 1, wherein the motor (8) causes driving of the belt (5) over the rotating pulley (7) and the idler pulley (6).

10. The machine as claimed in claim 1, wherein the supporting frames (3, 3’) are rotatably mounted to the wall of the chamber (2) through a bearing housing (11).

11. The machine as claimed in claim 1, wherein the walls of the closed chamber (2) provides efficient air circulation (A) within the chamber (2) around the mould.

12. The machine as claimed in claim 1, further comprising a burner (12), said burner is positioned to blow hot air such that hot air is circulated within the closed chamber (2) around the mould.

13. The machine as claimed in claim 12, further comprising a blower (13) mounted on the center-top of the chamber (2), the suction of blower (13) is oriented such that its suction takes air in from the top centre of the furnace and forces air along the walls of the chamber so as to enable efficient cooling and heating of the mould.

14. The machine as claimed in claim 11, wherein the wall of the chamber (2) are curved in shape.

15. The machine as claimed in claim 1, comprising a drive gearbox (9) for controlling the speed of rotation of the motor (8).

16. The machine as claimed in claim 1, wherein the chamber (2) provides atleast a first door (14) and a second door (14’), both first and second door located opposite to each other to provide direct air circulation (A).

17. The machine as claimed in claim 16, wherein the first door (14) has a first cavity for feeding the moulding material.

18. The machine as claimed in claim 16, wherein the first door (14’) has a second cavity for inspection of process.

19. The machine as claimed in claim 1, wherein the supporting frame (3, 3’) are made of light weight material.

20. The machine as claimed in claim 1, wherein the supporting frames (3, 3’) can have varying shapes and size to accommodate different size of moulds.

21. The machine as claimed in claim 1, wherein the mould mounting frames (3, 3’) can have varying shapes and to accommodate different size and quantities of moulds.