Claims:1. An apparatus for unloading at least one cured tire from a tire curing press, said apparatus comprising:
at least one chuck supporting shaft having at least one centering plate at one end and plurality of chucking paddle at other end, wherein said chucking paddle is slidably engaged with plurality of sliding rod;
at least one cam plate rotatably engaged with said chuck supporting shaft, said cam plate includes plurality of cam roller;
at least one rotating gear to provide at least one rotation to said cam plate, wherein said gear is actuated by linear displacement at least one supporting rack and at least one rotatable pinion;
wherein, said chucking paddle, activated based on rotation of said cam plate, said chucking plate adapted to slide inwards and/or outwards along said sliding rod and thereby grip at least one bead of said cured tire during unloading; and
said centering plate enabled to adjust centering of said paddle by plurality of centering blocks

2. The apparatus as claimed in claim 1, wherein said cam roller adapted to circumferentially move along a cam profile of said cam plate based on said rotation of said cam plate during unloading.

3. The apparatus as claimed in claim 1, wherein said supporting rack is coupled to said rotating gear at one end and at least one pneumatic cylinder at other end.

4. The apparatus as claimed in claim 3, comprises at least one idler roller to provide meshing between said supporting rack and said rotating gear.

5. The apparatus as claimed in claim 4, wherein said supporting rack is extended and/or retracted by means of said pneumatic cylinder to actuate said rotating gear.

6. The apparatus as claimed in claim 1, wherein said chucking paddle is mounted to at least one paddle block secured to said sliding rod.

7. The apparatus as claimed in claim 1, wherein said centering plate is adapted to maintain parallelism by means of plurality of fasteners.

8. The apparatus as claimed in claim 1, comprises plurality of fasteners to maintain concentricity and parallelism of said chuck support shaft.

9. The apparatus as claimed in claim 1, wherein the sliding rod having substantially square cross section.

10. The method for unloading at least one cured tire from a tire curing press using an unloading apparatus, said method comprising:
extending, by means of one or more pneumatic cylinder, at least one supporting rack for providing at least one linear displacement to said supporting rack;
actuating, by said linear displacement of said supporting rack, at least one rotating gear for providing at least one rotation to said rotating gear;
rotating, by said rotation of said rotating gear, at least one cam plate and thereby enabling said cam plate and plurality of cam roller to rotate;
sliding, by said rotation of said cam plate, said chucking paddles inwards on at least one sliding rod and thereby collapsing, said unloading apparatus;
adjusting, by means of at least one rotating arm, said unloading apparatus based on height of said cured tire;
retracting, by means said pneumatic cylinder, said supporting rack and thereby providing at least one reverse rotation to said rotating gear;
sliding, by said reverse rotation of said rotating gear, said chucking paddles outwards on said sliding rod until gripping at least one tire beads of said cured tire; and thereby
unloading, said cured tire by vertically displacing said rotating arm.

11. The method as claimed in claim 10, comprises centering of chucking paddles by adjusting plurality vertical faces of the at least one centering plate by means of plurality of fasteners mounted on plurality of centering blocks.

12. The method as claimed in claim 10, comprises parallelism adjustment of chucking paddles by adjusting plurality of horizontal face of one centering plate by means of plurality of fasteners.
, Description:TECHNIAL FIELD

[001] The present invention described herein, in general, relates to an unloader for unloading a cured/vulcanized tire in a tire curing machine. More particularly, the invention relates to a chuck assembly in the unloader for gripping and/or unloading the cured/vulcanized tire of nearly all sizes from the tire curing machine to a post-cure apparatus.

BACKGROUND

[002] A tire curing press has in its construction the capacity to cure different sizes of tires. An uncured or green tire is loaded in a special molds where all patterns and side wall branding of the tire occurs during a process of curing inside the tire curing press and thereby obtain a cured tire. The cured tire is then removed using a tire unloader apparatus, from the confines of the mold of the tire curing press for the next cycle of curing to start.

[003] The tire unloader is a pick and place apparatus customarily used with tire curing presses that aids in the process of removal of cured tire from a tire curing press. The cured tire is comprised of three major parts, namely the bead, the sidewall and the tread. Different sizes of tires have different bead sizes. One of the methods for handling of cured tires i.e. their removal from the press after curing is carried out by gripping or holding the bead of the tire. Accordingly, the tire unloader apparatus has a sub-assembly for gripping the bead of the cured tire namely a chuck assembly.

[004] Reference is made to US patent number 3,564,649, wherein a device for automatically loading and unloading a tire vulcanizing press. A loading and unloading chuck having gripping means is controlled by a pivoted motor so that tires, particularly large and heavy tires, can be adequately and safely carried to and from the press. The pivoted motor enables the chuck to maintain a sufficient and substantially constant radial holding force on the bead area of the tire so that no slippage occurs. The tire band holding or chuck assembly using a plurality of gripping paddle members, affords a wide range of radial adjustment by virtue of the plurality of curved guideways. Rotation of the plate causes rollers to move in guideways which, in turn, moves the paddle carrying trolley assemblies radially outward on spokes. To assure the trolleys do not move too far in either direction, boom is equipped with a stop switch, which will contact a projecting lug on plate to turn off the power that rotates plate. To supply that power for rotating plate and to assure that assembly provides a substantially constant radial force on the tire bead, particularly of a large and heavy tire, there is a provided a pivoting motor drive assembly. This device is having a complex arrangement without any concentricity and parallelism adjustment and therefore is less accurate.

[005] Reference is made to US patent number 4,614,485 wherein an unloader for a tire curing machine is improved in that a tire gripping device in the unloader is composed of a chuck base for depressing an upper bladder clamp ring upon lowering an arm which supports the tire gripping device to form a space for inserting chuck claws between inner circumferential portions of a bladder and a cured tire, chuck claws mounted on the chuck base so as to be expansible and contractible, and a chuck claw expansion/contraction hydraulic cylinder mounted on the chuck base. The prior art is also devoid of concentricity and parallelism adjustment and work with only two paddle configurations and thus there are chances of tire slipping during unloading if the tire is not parallel to mold after stripping.

[006] Reference is made to US patent number 4,401,422 wherein A chuck assembly for use in a loader of a tire vulcanizer including a ring-shaped chuck main casing having an inner cylinder of a bore long enough to allow entry of a press center mechanism including a center post, a bladder and so forth, an outer cylinder concentrically surrounding the periphery of the inner cylinder and an upper cover connecting the inner and outer cylinders, rails radially aligned between the inner and outer cylinders in the main casing, a plurality of chucking paddles held by sliders slidably extending on a respective one of the rails for movement along the rails, and a ring-shaped chuck cam rotatably disposed about a rotational axis of the inner cylinder in the chuck main casing, wherein slider shafts of one of the respective paddles are slidably engaged with working cam grooves radially aligned in the chuck cam. The arrangement described in the prior art is complex and is also devoid of concentricity and parallelism adjustment.

[007] Thus, keeping in view the existing unloader in tire curing press as mentioned above, the need to provide gripping of the tires involves a complex arrangement in the conventional mechanism. Further, most of such unloader are limited to unloading of only a single size of cured/vulcanized tire or additional adjustment mechanism are needed to unload different tire sizes. Furthermore, the convention unloader failed to adjust concentricity and parallelism of the cured tires with respect to other components or sub-assemblies. In recent years, the manufacture of tires has demanded excellence in uniformity and other properties of tires as well as high operating performances of tire vulcanizer.

[008] Therefore, there exists a dire need to provide a simple arrangement for gripping or holding tire and thereby unloading the said cured tire from the tire curing machine. Further the arrangement is able to cater to the need of concentricity and parallelism adjustment during the unloading mechanism.

SUMMARY OF THE INVENTION

[009] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[0010] The main object of the present invention is to provide an improved unloader for a tire curing machine having a simple arrangement and that overcomes the above mentioned drawbacks of the existing mechanism.

[0011] Another object of the present invention is to provide an improved cam-operated chuck assembly in unloader for gripping or holding cured tire and thereby enhancing the working efficiency of the unloading mechanism.

[0012] Yet another object of the present invention is to provide a simple arrangement for unloading one or more cured tire/vulcanized tire of different sizes without any additional alteration and adjustments required in the arrangement.

[0013] Still another object of the present invention is to provide an unloader for unloading a cured/vulcanized tire by converting a rotation motion of a cam plate in the cam-operated chuck assembly to the linear motion of the paddles.

[0014] Accordingly, in the first aspect of the present invention, there is provided an apparatus for unloading at least one cured tire from a tire curing press, said apparatus comprising:

at least one chuck supporting shaft having at least one centering plate at one end and plurality of chucking paddle at other end, wherein said chucking paddle is slidably engaged with plurality of sliding rod;
at least one cam plate rotatably engaged with said chuck supporting shaft, said cam plate includes plurality of cam roller;
at least one rotating gear to provide at least one rotation to said cam plate, wherein said gear is actuated by linear displacement at least one supporting rack and at least one rotatable pinion;
wherein, said chucking paddle, activated based on rotation of said cam plate, said chucking plate adapted to slide inwards and/or outwards along said sliding rod and thereby grip at least one bead of said cured tire during unloading; and
said centering plate enabled to adjust centering of said paddle by plurality of centering blocks.

[0015] In the second aspect of the present invention, there is provided a method for unloading at least one cured tire from a tire curing press using an unloading apparatus, said method comprising:
· extending, by means of one or more pneumatic cylinder, at least one supporting rack for providing at least one linear displacement to said supporting rack;
· actuating, by said linear displacement of said supporting rack, at least one rotating gear for providing at least one rotation to said rotating gear;
· rotating, by said rotation of said rotating gear, at least one cam plate and thereby enabling said cam plate and plurality of cam roller to rotate;
· sliding, by said rotation of said cam plate, said chucking paddles inwards on at least one sliding rod and thereby collapsing, said unloading apparatus;
· adjusting, by means of at least one rotating arm, said unloading apparatus based on height of said cured tire;
· retracting, by means said pneumatic cylinder, said supporting rack and thereby providing at least one reverse rotation to said rotating gear;
· sliding, by said reverse rotation of said rotating gear, said chucking paddles outwards on said sliding rod until gripping at least one tire beads of said cured tire; and thereby
· unloading, said cured tire by vertically displacing said rotating arm.

[0016] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0017] The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:
[0018] Figure 1 illustrates the left side view of the Cam operated Chuck with Paddles in collapsed position, in accordance with an embodiment of the present invention.
[0019] Figure 2 illustrates the front view of the Cam operated Chuck with Paddles in collapsed position, in accordance with an embodiment of the present invention.
[0020] Figure 3 illustrates the top view of the Cam operated Chuck, in accordance with an embodiment of the present invention
[0021] Figure 4 illustrates the Isometric view of Cam operated Chuck, in accordance with an embodiment of the present invention
[0022] Figure.5 illustrates the Bottom view of the Cam operated Chuck with Paddles in both collapsed and fully out positions, in accordance with an embodiment of the present invention
[0023] Figure.6 illustrates Cross-sectional view of Cam operated Chuck, in accordance with an embodiment of the present invention

[0024] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0025] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0026] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0027] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0028] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0029] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0030] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0031] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0032] In one implementation, the present invention provides a cam operated chuck assembly to fulfill the objectives of the present invention.

[0033] In one implementation, reference is made to figure 1 wherein the left side view of the Cam operated Chuck with Paddles in collapsed position is illustrated.

[0034] In one implementation, reference is made to figure 2 wherein the front view of the Cam operated Chuck with Paddles in collapsed position is illustrated.

[0035] In one implementation, reference is made to figure 3 wherein the top view of the Cam operated Chuck is illustrated.

[0036] In one implementation, reference is made to figure 4 wherein the isometric view of Cam operated Chuck is illustrated.

[0037] In one implementation, reference is made to figure.5 wherein the bottom view of the Cam operated Chuck with Paddles in both collapsed and fully out positions is illustrated.

[0038] In one implementation, reference is made to figure.6 wherein a cross-sectional view of Cam operated Chuck is illustrated.

[0039] In one implementation, the components as shown in figure 1-6 are individually numbered where the numbers refer to the following:
1. Paddle or chucking paddles
2. Paddle Block
3. Cam Plate
4. Square Sliding Rod
5. Cam Rollers
6. Cam Lock Nut
7. Lock Pin
8. Chuck Support Shaft
9. Rotating Arm (Not a part of current inventive apparatus).
10. Rack
11. Pneumatic Cylinder
12. Gear
13. Chuck Support Shaft Bush
15. Idler Roller Pin
16. Idler Roller
17. Centering Plate
18. Centering Block
20. Cylinder Trunnions
21. Shaft Lock Pin
22. Fastener set
23. Fastener set

[0040] In one implementation, the cam operated chuck assembly comprises:
· at least one chuck support shaft (8);
· at least four square sliding rods (4) which are mounted to the chuck support shaft (8) held by four lock pins (7);
· at least four paddle blocks (2) which slide in and out over the square sliding rods (4);
· at least four paddles (1) which are mounted to the paddle blocks (2);
· at least four cams rollers (5) which move between a cam profile in the cam plate (3);
· at least four cam lock nuts (6) which hold the cam rollers (5) in position with the paddle block (2);
· at least one gear (12) which are mounted to the cam plate (3) with a plurality of fasteners;
· at least two chuck support shaft bushes (13) which support the chuck support shaft (8) providing bushing to the support shaft inside a rotating arm (9) bore;
· at least two cylinder Trunnions (20) which are mounted to the rotating arm (9) with a plurality of fasteners;
· at least one pneumatic cylinder (11) which is mounted to the cylinder trunnion (20);
· at least one rack (10) whose one end is connected to the pneumatic cylinder (11) which also meshes with the gear (12);
· at least one idler roller pin (15) mounted to the rotating arm (9) which also houses the idler roller (16) which ensures the meshing between the rack (10) and the gear (12);
· at least one centering plate (17) which is connected to the top end of the chuck support shaft (8) with a fastener;
· at least four centering blocks (18) which are connected to the rotating arm (9) with a plurality of fasteners;
· at least one shaft lock pin (21) which secures the chuck support shaft (8) with the rotating arm (9);
· at least four sets of fasteners (Hexagonal Head Bolt with full thread and Nut) (22) for maintaining concentricity of chuck support shaft (8);
· at least four sets of fasteners (Hexagonal Head Bolt with full thread and Nut) (23) for maintaining parallelism of chuck support shaft (8)

[0041] The present invention provides an apparatus with a simple arrangement of unloading a cured tire and a method thereof. In one implementation, a rotational motion of a cam plate about its axis is which is initiated by an arrangement of rack and pinion and this circular motion is translated into the linear movement of chucking paddles which move circumferentially in or out which responsible for gripping of the tire’s bead. For gripping the bead of the tires, the chucking paddles collapse for the chuck to enter into the bead. After the paddles enter between the beads, they move circumferentially out until the bead comes into contact. Arrangements of linkages or a cam and cam follower mechanism are historically used to perpetuate this motion. In the present invention, a simple cam and cam follower mounted to a paddle block which slides over a square sliding rod is used convert the rotational motion of the cam to the linear movement of the paddles.

[0042] In one implementation, when the necessity arises for the cured tire to be removed from the tire curing press for the next cycle to start, the rotating arm (9) may swing inwards until the chuck assembly and the curing mold are concentric with each other. Simultaneously, the collapsing of the chuck which refers to the movement of the paddles (1) circumferentially inwards takes place.

[0043] In one implementation, the chuck collapse occurs when a control system operates the pneumatic cylinder (11) displacing the rack (10) linearly which in turn rotates the gear (12) due to the rack and pinion arrangement. The cam plate (3) rotates along with the rotating gear (12) as it is held together by a plurality of fasteners. The rotation of the cam plate (3) makes the plurality of cams rollers (5) follow cam profiles machined out of the cam plate (3) causing the paddles blocks (2) move circumferentially inwards while sliding over a plurality of substantially square sliding rods (4) mounted to the chuck support shaft (8). Since the chucking paddles (1) are mounted to the paddle block (2) the collapsing of chuck occurs as shown in figure 1 and 2.

[0044] In one implementation, when the chuck assembly collapses, the rotating arm (9) may vertically displace and stopped at a point depending upon the height of the cured tire when the paddles (1) are between the beads of the tire. The pneumatic cylinder (11) is now operated with a control input which retracts the rack (10) which reverses the gear (12) motion causing the paddles (1) to move circumferentially outwards. This motion continues until the paddles (1) come into contact with the bead of the tire gripping it. Further movement of the paddles is controlled by a stopper block which may be placed to arrest its movement depending on the size of the bead. After gripping the tire, the rotating arm (9) moves vertically up to pick up or remove the cured tire from the mold and place it on conveyors or auxiliary apparatuses for further processing or are directed for inspection. At this instance, the cam operated chuck assembly is in fully out position as shown in figure 5.

[0045] In one implementation, the cam plate (3) when rotates, may slide over the chuck support shaft (8) provided with bushes (12). The chuck support shaft (8) is mounted to the rotating arm (9) with a shaft lock pin (21) and plurality of fasteners. Over the top surface of the chuck support shaft (8) is a centering plate (17) mounted. The centering of paddles (1) is carried out by adjusting the four vertical faces of the square centering plate (17) by means of a plurality of fasteners (22) mounted on a plurality of centering blocks (18) mounted to the rotating arm (9). Another functionality of the centering plate (17) is to maintain parallelism with the help of a plurality of fasteners (23).

[0046] In one implementation, the pneumatic cylinder (11) is mounted to the rotating arm (9) on a pair of cylinder trunnions (20). The meshing of the rack (10) and the gear (12) is ensured by an idler roller (16) which is mounted to the rotating arm (9) with an idler roller pin (15) and a plurality of fasteners. The square sliding rods (4) are mounted to the chuck support shaft (8) with a plurality of lock pins (7). The centering plate (17) is registered and mounted to the chuck support shaft (8), thus any adjustments for concentricity and parallelism to the former changes the position of the chuck support shaft (8).

[0047] Some of the important features of the present invention, considered to be noteworthy are mentioned below:

· The apparatus and method of the present invention provides gripping tire with cam plate, square sliding rod, cam roller, rack and pinion, chuck support shaft and pneumatic cylinder.
· The apparatus and method of the present invention provides parallelism and concentricity adjustment with centering plate, chuck support shaft, adjustment blocks, fasteners and lock nuts.
· The present invention involves reduced number of components with respect to conventional mechanism equipment, thereby reducing cost.
· The present invention includes an intrinsic assembly feature for concentricity and parallelism adjustment.
· The apparatus of the present invention is easy to manufacture, reducing lead time.
· The apparatus of the present invention is easy to assemble due to the reduced number of components than conventional mechanism.
· The apparatus of the present invention includes a simple operation.
· The apparatus of the present invention is easy to maintain.

[0048] It may be understood by the person skilled in that art that, the coupling, joining, fitting, fastening, of the two components mentioned the present invention may be achieved by any of the existing coupling techniques that may include but not limited to nuts and screws, stepper bolt, hexagonal bolt with or without full thread or any combination thereof.

[0049] Although an apparatus for unloading a vulcanized tire and a method thereof have been described in language specific to structural features, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or methods or devices described. Rather, the specific features are disclosed as examples of implementations of an apparatus for unloading a vulcanized tire and a method thereof