Claims:1. A center mechanism for manipulating a bladder in a tire curing press comprising,
at least one top ring cylinder rod 10 having at least one fastener 11 for at least one top clamp ring clamp 12 adapted to manipulating a bladder in a tire curing press;
at least one cylinder guide 14 adapted to provide a passage for slidable movement of the at least one top ring cylinder rod 10;
at least one lower ring cylinder rod 35;
at least one top ring cylinder 16;
at least one cylinder guide shaft 18;
wherein the center mechanism is characterized in that the at least one lower ring cylinder front flange 36 is mounted directly on the at least one cylinder guide 14 and the at least one lower ring cylinder rod 35 is coupled directly with the at least one top ring cylinder front flange 37.

2. The center mechanism as claimed in claim 1, wherein the at least one fastener 11 for the at least one top clamp ring clamp 12 is coupled with the at least one top ring cylinder rod 10.

3. The center mechanism as claimed in claim 1, further comprises the at least one guide shaft 24 threaded to lower clamp ring hub 13

4. The center mechanism as claimed in claim 1 further comprises at least one linear position sensing device 19 having at least one linear position sensing device guard 20.

5. The center mechanism as claimed in claim 1 further comprises at least one mold register ring 21, and at least one cap plate 31.

6. The center mechanism as claimed in claim 1 further comprises at least one cure media supply pipe 22 adapted to carry at least one curing media during the curing process.

7. The center mechanism as claimed in claim 1, wherein the at least one lower ring cylinder 15 further comprises at least one lower ring cylinder linear position sensing device 23.

8. The center mechanism as claimed in claim 1 further comprises at least one guide plate 24 mounted to at least one lower ring cylinder mid flange 34. Guide plate 24 is adapted to provide a passage for at least one top ring cylinder 16, the at least one cylinder guide shaft 18, the at least one cure media supply pipe 22 and at least one curing medium pipe bush 29.

9. The center mechanism as claimed in claim 1, wherein the at least one lower ring cylinder 15 is mounted directly on the at least one cylinder guide 14 using a lower ring cylinder front flange 36.

10. The center mechanism as claimed in claim 1, wherein the at least one lower ring cylinder rod 35 is coupled directly with the at least one top ring cylinder 16 using a nut 17.

11. The center mechanism as claimed in claim 1, wherein the center mechanism is characterized in that having less number of parts and reduction in overall height of the assembly.

12. The center mechanism as claimed in claim 1, wherein the center mechanism is further characterized in that the at least one lower ring cylinder rod 35 is coupled directly with the at least one top ring cylinder 16 using a nut 17 to provide the at least one lower ring cylinder rod 35 to serve as an additional guide.

13. The center mechanism as claimed in claim 1, further comprises at least one cylinder guide having at least one cylinder guide bush 26 adapted to guide the at least one lower ring cylinder piston rod 35 and the at least one cylinder guide shaft 18 during lower ring cylinder 15 stroke

14. The center mechanism as claimed in claim 1, further comprises at least one cylinder guide having at least one guide plate 24 and at least one cylinder guide bush 26, the at least one cylinder guide bush 26 adapted to guide at least one cylinder guide shaft 18 during lower ring cylinder 15 stroke

15. The center mechanism as claimed in claim 1, further comprises at least one guide plate 24 having at least one cure media pipe bush 29, the at least one cure media pipe bush 29 adapted to guide at least one cure media supply pipe 22 during lower ring cylinder 15 stroke.
, Description:TECHNICAL FIELD

[001] The present subject matter described herein, in general, relates to a tire curing press, and more particularly to a center mechanism of a tire curing press which holds and lifts a bladder assembly. More specifically, to a center mechanism which is able to easily mount and remove the bladder assembly.

BACKGROUND

[002] As conventionally known, Tire curing is the process of applying pressure to the green tire in a mold in order to give it its final shape, and applying heat energy to stimulate the chemical reaction between the rubber and other materials.

[003] Numerous types of presses for shaping and curing tires have been developed over the years. One major construction feature of such presses is the mechanism for actuating the upper and lower mold sections for opening and closing the press to permit removal of a cured tire and insertion of an uncured tire on the one hand and the controlled pressurizing and heating of the tires within the mold sections on the other hand. In this respect, successful mechanisms for opening and closing presses have been developed that feature both mechanical and hydraulic actuation.

[004] Another significant feature of such tire curing presses is the center mechanism, which provides the primary interaction between the press and a tire band being processed by the press, particularly during the manipulations of loading and unloading tires into the press. While various types of center mechanisms have been developed over the years, the most universally accepted have employed a flexible, generally cylindrical bladder or bag member that is secured to the press and that is capable of manipulation to be inserted within a tire band, radially distended in order to apply shaping pressure and curing pressure and heat to the interior of the tire band, and to strip the bladder from the tire after the curing process is completed.

[005] The factors involved in operation of a center mechanism bladder in conjunction with conventional bias-ply tires were relatively simple due to the cylindrical form of the uncured tire. With the wide acceptance of radial-ply tires, bladder manipulations assumed more complex and significant implications. Since uncured or green radial tire carcasses must be at least partially preformed before the breaker ply is positioned and affixed, the bead portions are, therefore, necessarily in closer axial proximity to each other in that the preformed tire band approximates, to a substantial extent, the configuration of the cured tire, as contrasted with the substantially cylindrical uncured configuration of a conventional bias-ply tire. As a result, the bead-to-bead dimension interiorly of a preformed radial tire substantially exceeds the axial distance between the beads. Therefore, a bladder or bag that has an axial extent that approximates the bead-to-bead dimension interiorly of a tire will, when axially upwardly extended to receive the tire, project a substantial distance above the upper bead of the tire. In such instances, movement of the upper and lower bead area of a bladder, together with control of the internal pressure, are significant in accurately concentrically locating the bladder within the tire to complete shaping and perform curing of a green radial tire band.

[006] Center mechanisms employing a generally cylindrical bag or bladder member have assumed many forms in the commercial environment; however, it has been realized in recent years that the configuration of the bladder and its accuracy of placement within an uncured tire band are highly significant to the uniformity and, therefore, performance of the resultant cured tire. Many center mechanisms have inherent weaknesses or disadvantages based solely upon the construction of the bag or bladder and the manner in which it is attached to and manipulated by components of a center mechanism. For example, a bladder that is not symmetrical about both horizontal and vertical axes can readily lead to a lack of uniformity in the resultant tires. In instances where the bladder beads are fixed, the girth of the bladder is limited. In bladders having fixed beads at one end and a free end of the bladder, there is necessarily poor control over the free end of the bladder during bladder insertion into the uncured tire band. Further, in some instances, large volumes of curing media are required due to the bladder and center mechanism configuration. Most prior-art center mechanisms that are currently in commercial use suffer from one or more of the above limitations. One prior-art center mechanism that is not subject to the above-described disadvantages is the Bag-O-Matic center mechanism.

[007] Current technology has a center mechanism which clamps the bladder between top clamp ring and lower clamp ring and lifts a bladder assembly which is used for shaping and curing of tires. The center mechanism comprises the bladder assembly with the top and lower ends of a bladder clamped with top clamp ring and lower clamp ring support mem¬bers, a hydraulic cylinder for positioning the top clamp ring, which manipulates a bladder position relative to a tire. The center mechanism also comprises two more hydraulic cylinders which lifts the lower clamp ring along with the bladder so as to eject the tire from lower mold. Center mechanism has singular or plurality of pathway to supply and drain curing media such as, but not limited to steam, hot water and nitrogen.

[008] Bladder control mechanism encompasses two functions, first hydraulic cylinder (called as Top ring cylinder) inbuilt with Linear position sensing device, which manipulated the bladder height relative to tire. The second function, using two hydraulic cylinders (also called as lower ring cylinders) which lift the top ring hydraulic cylinder along with top clamp ring, bladder and lower clamp ring, this in turn ejects the tire from the lower mold. Apart from these functions the bladder control mechanism also used to supply and drain cure media which could be hot water, steam or nitrogen, but not limited to only these.
[009] However, in conventional methods, the arrangement of lower ring cylinders and top ring cylinders is complex and has many parts. The overall height also is more which needs higher pit depths to accommodate center mechanism. Thus, there was a need to reduce the number of parts required in the center mechanism, to make the arrangement simpler, and to reduce the overall height of center mechanism.

[0010] The above-described deficiencies of today's Bladder control mechanisms are merely intended to provide an overview of some of the problems of conventional systems, and are not intended to be exhaustive. Other problems with conventional systems and corresponding benefits of the various non-limiting embodiments described herein may become further apparent upon review of the following description.

SUMMARY OF THE INVENTION

[0011] 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.

[0012] An object of the present invention is to provide a bladder control mechanism, more specifically center mechanism with reduction in number of parts and overall height of assembly.

[0013] Another object of the present invention is to provide a bladder control mechanism, more specifically center mechanism, having additional guide of positioning bladders and stripping tires in a tire curing press.

[0014] Accordingly, a center mechanism for a press for shaping and curing tires is disclosed. The center mechanism includes at least one top ring cylinder rod having at least one fastener for at least one top clamp ring clamp adapted to manipulating a bladder in a tire curing press; at least one cylinder guide adapted to provide a passage for slidable movement of the at least one top ring cylinder rod; at least one lower ring cylinder; at least one top ring cylinder; and at least one cylinder guide shaft. The center mechanism is characterized in that the at least one lower ring cylinder is mounted directly on the at least one cylinder guide and the at least one lower ring cylinder is coupled directly with the at least one top ring cylinder.

[0015] In contrast to the prior-art, the present invention provides the at least one lower ring cylinder is mounted directly on the at least one cylinder guide and the at least one lower ring cylinder is coupled directly with the at least one top ring cylinder, which enables reduction in number of parts and overall height of assembly. Further, the present invention enables the Lower Ring Cylinder Piston rod to serve as additional guide.

[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 a cross-sectional side view of Center Mechanism with press in closed condition having top ring cylinder and lower ring cylinder are in fully retracted condition, top clamp ring, bottom clamp ring, bladder, tire and mold shown, in accordance with an embodiment of the present invention.

[0019] Figure 2 illustrates a cross-sectional side view of center mechanism with press in open condition having top ring cylinder in extended, lower ring cylinder in fully retracted condition, bladder in stretched condition, top clamp ring and lower clamp ring shown, in accordance with an embodiment of the present invention.

[0020] Figure 3 illustrates a cross-sectional side view of center mechanism with top ring cylinder and lower ring cylinder in extended condition, bladder in stretched condition, top clamp ring and lower clamp ring shown, in accordance with an embodiment of the present invention.

[0021] Figure 4 illustrates a cross-sectional front view of center mechanism with top ring cylinder and lower ring cylinder fully retracted condition, top clamp ring and bottom clamp ring shown, in accordance with an embodiment of the present invention.

[0022] Figure 5 illustrates a cross-sectional front view of center mechanism with Top ring cylinder fully retracted, lower ring cylinder in extended condition, top clamp ring and bottom clamp ring shown, in accordance with an embodiment of the present invention.

[0023] Figure 6 illustrates a top cross-sectional view of center mechanism guide plate construction showing position of top ring cylinder, lower ring cylinder, cure media supply pipe, cylinder guide, in accordance with an embodiment of the present invention.

[0024] Figure 7 illustrates a top cross-sectional view of center mechanism having RTD, top ring cylinder, bottom ring cylinder and seal shown, in accordance with an embodiment of the present invention.

[0025] Figure 8 illustrates a bottom view of centre mechanism, in accordance with an embodiment of the present invention.

[0026] Figure 9 illustrates a general view of centre mechanism, in accordance with an embodiment of the present invention.

[0027] Figure 10 illustrates a cross-sectional side view of center mechanism with top ring cylinder and lower ring cylinder in fully retracted condition, in accordance with an embodiment of the present invention.

[0028] Figure 11 illustrates a cross-sectional side view of center mechanism with top ring cylinder retracted condition and lower ring cylinder in extended condition, in accordance with an embodiment of the present invention.

[0029] 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 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

[0030] 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.

[0031] 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.

[0032] 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.

[0033] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] The present invention relates to apparatus for utilization in tire curing presses for clamping bladder with top and lower rings, positioning bladder, stretching bladder, shaping bladder, stripping or ejecting tire from lower mold and curing tires. The present invention relates to apparatus for handling and positioning bladders and stripping tires. More particularly the present invention relates to a simple arrangement of top ring and lower ring (bead lift) actuating devices. The total assembly is called as center mechanism or bladder control mechanism. The present invention is capable of supplying, circulating and draining of the cure media as listed, but not limited to steam, hot water and nitrogen, in the bladder used to cure the tires at prescribed pressure, temperature and duration as well as control the bladder according to the aspect ratio of the bladder for shaping, curing and vacuum. The present invention is capable of forcefully strip or eject tire from lower half of mold, so as to unload the cured tire.

[0038] The present invention relates the machinery for manufacturing tires in motor vehicles of nearly all sizes.

[0039] The components given in the figures are individually numbered where the numbers refer to the following:
1. Top clamp ring
2. Lower Clamp Ring
3. Tire
4. Top Mold
5. Bottom Mold
6. Bladder
7. Platen
8. Platen Support
9. Platen Insulation
10. Top Ring Cylinder Rod
11. Fastener for Top Clamp Ring Clamp
12. Top Clamp Ring Clamp
13. Lower Clamp Ring Hub
14. Cylinder Guide
15. Lower Ring Cylinder
16. Top Ring Cylinder
17. Nut For Connecting Lower Ring Cylinder to Top Ring Cylinder
18. Cylinder Guide Shaft
19. Linear Position Sensing Device
20. Linear Position Sensing Device Guard
21. Mold Register Ring
22. Cure Media Supply Pipe
23. Lower Ring Cylinder Linear Position Sensing Device
24. Guide Plate
25. Lower Clamp Ring Hub Insulation
26. Cylinder Guide Bush
27. Top Ring Cylinder Rod Bush
28. Seal
29. Curing Medium Pipe Bush
30. Lower Clamp Ring/Hub Threads
31. Cap Plate
32. Resistance Temperature Detector (RTD )
33. Top ring Cylinder Port
34. Lower Ring Cylinder Mid Flange
35. Lower Ring Cylinder Rod
36. Lower ring Cylinder front flange
37. Top ring cylinder front flange

[0040] In one implementation, a center mechanism for manipulating a bladder in a tire curing press is disclosed. The center mechanism includes at least one top ring cylinder rod 10 having at least one fastener 11 for at least one top clamp ring clamp 12 adapted to manipulating a bladder in a tire curing press; at least one cylinder guide 14 adapted to provide a passage for slidable movement of the at least one top ring cylinder rod 10; at least one lower ring cylinder rod 35; at least one top ring cylinder 16; at least one cylinder guide shaft 18. The center mechanism is characterized in that the at least one lower ring cylinder 15 is mounted directly on the at least one cylinder guide 14 and the at least one lower ring cylinder rod 35 is coupled directly with the at least one top ring cylinder front flange 37.

[0041] In one implementation, the at least one fastener 11 for the at least one top clamp ring clamp 12 is coupled with at least one top ring cylinder rod 10.

[0042] In one implementation, the center mechanism further includes at least one linear position sensing device 19 having at least one linear position sensing device guard 20.

[0043] In one implementation, the center mechanism further includes at least one mold register ring 21, and at least one cap plate 31.

[0044] In one implementation, the center mechanism further includes at least one guide plate 24 mounted to at least one lower ring cylinder mid flange 34. Guide plate 24 is adapted to provide a passage for at least one top ring cylinder 16, the at least one cylinder guide shaft 18, the at least one cure media supply pipe 22 and at least one curing medium pipe bush 29.

[0045] In one implementation, the center mechanism further includes at least one cylinder guide shaft 18 threaded to lower clamp ring hub 13, that is getting guided in cylinder guide 14 and guide plate 24 by using at least one cylinder guide bush 26. The center mechanism further includes at least one cylinder guide 14, at least one guide plate 24, and at least one cylinder guide bush 26, guide the guide shaft 18 during lower ring cylinder 15 stroke.

[0046] In one implementation, the at least one lower ring cylinder 15 is mounted directly on the at least one cylinder guide 14 using a lower ring cylinder front flange 36.

[0047] In one implementation, the at least one lower ring cylinder rod 35 is coupled directly with the at least one top ring cylinder front flange 37 using a nut 17.

[0048] In one implementation, the bottom mold section 12 is located on an upper surface of the heat plate 6 connected to a top surface of the squeeze cylinders pistons 16.

[0049] Figure 1 illustrates the cross-section of the present invention in closed condition of the tire curing press and Figure 2 illustrates the open condition. The tire is cured in mold which is made up of two halves; the lower mold 5 is fixed to the bottom platen 7, by plurality of fasteners. Lower mold 5 is registered to mold register ring 21. Bottom platen 7 is fixed to bottom platen support 8, by plurality of fasteners. Bottom platen 7 and bottom platen support 8 are separated by a non-asbestos insulation plate 9. Figure 1 illustrates the press in curing condition, top clamp ring 1 is fixed to top clamp ring cylinder rod 10, using a clamp 12 and fasteners 11. Lower clamp ring 2 and lower clamp ring (LCR) hub 13 have threads 30 on them. They are connected to each other by these threads 30. Bladder 6 is clamped between top clamp ring 1 and lower clamp ring 2. Bladder 6 is shaped with cure media at high pressure and temperature to cure tire 3. Tire 3 is enclosed between top mold 4 and bottom mold 5. Cure media is supplied by cure media supply pipe 22. Cure media supply pipe 22 and lower clamp ring hub 13 are connected by plurality of fasteners. Cylinder guide 14, guide plate 24, and cure medium pipe bush 29 guides the cure media supply pipe 22 during lower ring cylinder 15 stroke.

[0050] Cylinder guide 14 is registered and fixed to bottom platen support 8 by plurality of fasteners. Lower ring cylinder front flange 36, is fixed to cylinder guide 14 by plurality of fasteners. Lower ring cylinder rod 35 end is registered to top ring cylinder front flange 37 and secured with a nut 17. Mold Register ring 21 is fixed to cylinder guide 14. in the present invention lower ring cylinder 15 is directly connected to cylinder guide 14 and coupled with top ring cylinder 16, thereby reducing number of parts and overall height of assembly. Lower ring cylinder 15 is having a mid flange 34. Top ring cylinder 16 is having front flange and downward facing ports 34 for easy coupling with lower ring cylinder 15.

[0051] Lower clamp ring 1 is actuated by lower ring cylinders 15, which lifts the top ring cylinder 16, lower clamp ring hub 13, lower clamp ring 2, thereby ejecting the tire 3 from bottom mold 5. Lower ring cylinder rod 35 is guided by cylinder guide 14 by using cylinder guide bush 26. During actuation of lower ring cylinder 15, guide shafts 18 provide additional support to lower ring cylinder 16 rods. Guide plate 24 guides the guide shaft 18 during actuation of lower ring cylinder 16. Guide plate 24 is connected to lower ring cylinder mid flange 34 by plurality of fasteners. For this lower ring cylinder 15 is having a mid flange 34. Bush 26 and 29 are provided in cylinder guide 14 and guide plate 24 to guide, guide shafts 18 and to take care of friction during actuation of lower ring cylinder.

[0052] Top clamp ring 1 is actuated by top ring cylinder 16 as shown in figure 2. The position of top clamp ring 1 is manipulated relative to tire 3 with linear position sensing device 19. Linear position sensing device 19 is inbuilt in top ring cylinder 16. Linear position sensing device 19 is protected by guard 20. Actuation of the lower ring cylinder 15 is sensed by a linear position sensing device 23. Linear position sensing device 23 is inbuilt in one lower ring cylinder 15.

[0053] Bottom mold 5 is registered to ring register 21. Register ring 21 is registered to cylinder guide 14. Cure media supply and drain pipes 22 are fixed to lower clamp ring hub 13. Top ring cylinder rod bush 27 is registered and fixed to lower clap ring hub 13, and takes care of friction between top ring cylinder rod 10 and lower clamp ring hub 13. Seal 28 prevents curing media from leaking. RTD 32 senses the temperature of cure media inside the bladder 6. Cap plate 31 serves as retainer for seal assembly.

[0054] Referring now to figure 3 a cross-sectional side view of center mechanism with top ring cylinder and lower ring cylinder in extended condition, bladder in stretched condition, top clamp ring and lower clamp ring is illustrated in accordance with an embodiment of the present invention.

[0055] Figure 4 a cross-sectional front view of center mechanism with top ring cylinder and lower ring cylinder fully retracted condition, top clamp ring and bottom clamp ring is illustrated, in accordance with an embodiment of the present invention.

[0056] Referring now to figure 5 a cross-sectional front view of center mechanism with top ring cylinder fully retracted, lower ring cylinder in extended condition, top clamp ring and bottom clamp ring is illustrated in accordance with an embodiment of the present invention.

[0057] Referring now to figure 6 a top cross-sectional view of center mechanism guide plate construction showing position of top ring cylinder, lower ring cylinder, cure media supply pipe, and cylinder guide is illustrated in accordance with an embodiment of the present invention.

[0058] Referring now to figure 7 a top cross-sectional view of center mechanism having RTD, top ring cylinder, bottom ring cylinder and seal is illustrated in accordance with an embodiment of the present invention.

[0059] Referring now to figure 8 a bottom view of centre mechanism is illustrated in accordance with an embodiment of the present invention.

[0060] Referring now to figure 9 a general view of centre mechanism is illustrated in accordance with an embodiment of the present invention.

[0061] Referring now to figure 10 a cross-sectional front view of center mechanism with top ring cylinder and lower ring cylinder fully retracted condition, in accordance with an embodiment of the present invention is illustrated.

[0062] Referring now to figure 11 a cross-sectional front view of center mechanism with top ring cylinder fully retracted and lower ring cylinder fully extended condition, in accordance with an embodiment of the present invention is illustrated.

[0063] Although an improved center mechanism of tire curing press is disclosed, 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 the improved center mechanism of tire curing press.