Compact Chuck Assembly For Tire Curing Press Field of the invention

The present invention relates to a tire loader in a tire curing press, and more particularly, the present invention relates to a compact chuck assembly for loading and unloading in the tire curing press.

Background of the invention

Conventionally, tire to be cured in a tire curing presses were loaded by hand and later by automatic loading mechanisms which positions the tire to be cured on a lower mold section of the tire curing press. By automating the gripping, transporting and releasing the tires, cost of manual labor was eliminated.

With the wide acceptance of radial ply tires, accurate positioning of uncured tire with respect to the lower mold cavity of the tire curing press have become increasingly important to produce good quality tires. The repeatability of this process for a large number of cycle is also very important for the tire manufactures. It is required that the tire loader should make sure that this repeated accuracy and reliability is provided to the tire curing press. The tire loader assembly includes two separate parts such as a swing arm assembly and chuck assembly which work in conjunction to provide repeated accuracy to the process of tire placement in the lower mold cavity of the curing press.

Specifically, the swing arm assembly should have repeated accuracy to move the tire from one point to another in a horizontal plane. The paddles of the chuck assembly should maintain precise concentricity with a axis thereof. For providing precise repeated concentricity of the paddles with the center of the chuck, each paddle should be provided with provision for individual position adjustment and provision for synchronized movement of all paddles should also be there. During the synchronized motion of the paddles for holding different bead sizes, the paddle assembly should maintain precise concentricity with the chuck axis. There should also be provision for individual adjustment of the paddle so that the fine tuning of the paddle assembly can easily be done without the requirement of dismantling the paddle assembly.

Various mechanisms are available to perform the above mentioned functions. In some cases, the paddles moving through a slide bushes actuated by cam or linkages are used. Alternatively, individual cylinders for actuating each paddle are used. Also, various mechanism are employed for individual adjustment of the paddle which include tedious process of dismantling of different parts of the assembly. Further, different methods of paddle synchronization, which includes rollers, retainers, linkages and guided rings are also available. Most of these mechanisms are very heavy, very time consuming and with very little repeatability due to high wear and tear.

Specifically, US Patent application No. 20100159048 discloses a loader basket for gripping, transporting, and releasing tires, including a fixed ring, a rotating ring operatively interrelated with the fixed ring, a plurality of shoe arms pivotally attached to the fixed ring, shoe assemblies pivotally mounted on each of the shoe arms, alignment links pivotally mounted on the fixed ring and pivotally attached to each of the shoe assemblies, shoe arm actuating rods pivotally attached to each of the shoe arms and the rotating ring for pivoting the shoe arms about the fixed rings while maintaining, the shoe assemblies in concentric relation during movement between collapsed and expanded positions, and an actuator for selectively moving the rotating ring relative to the fixed ring.

Another US Patent No. 4,744,739 discloses a tire press having upper and lower cavity molds with a tire loader which is vertically and horizontally movable and has a chuck which grips a tire by the tread rather than the bead. The gripper has plural gripping shoes movable by bell-cranks and piston actuators. The chuck of the invention grips a tire by the tread and positions it adjacent a mold where the tire bead is gripped by a second chuck (not claimed) which deposits the tire in the mold.

Yet another US Patent No. 4,279,438 discloses loader for tire machinery such as tire presses, in which loader is supported from a vertically and horizontally movable frame and which includes a vertical shaft or sleeve journaled with respect to the frame with a horizontal plate secured for rotation therewith. Loader shoes are mounted on the frame for radial movement and respective links interconnect the plate and each loader shoe, each link extending at a common angle with respect to a radius from the center of rotation of the plate, and rotation of the plate in one direction will reduce the angle accordingly moving the shoes radially outwardly and rotation of the plate in the opposite direction will increase the angle moving the shoes radially inwardly. Each link is adjustable in length and the extent of rotation of the plate in one or both directions is limited by adjustable stops. The loader shoes remain parallel throughout their movement and are supported for radial movement by self-aligning slider blocks.

Still another US Patent No. 4,401,422 discloses 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.

One more US Patent Application No. 2011/088812 discloses a combination loader and post cure tire inflator for use with a tire press is provided. A post cure inflator for inflating and curing vulcanized tires includes a plurality of inflator stations with each inflator station including a pair of axially aligned, vertically separable tire inflating chuck rings. A loading apparatus includes a loading arm movable along a linear track relative to the plurality of inflator stations to load and unload each vulcanized tire in a selected one of the plurality of inflator stations without rotating the vulcanized tires in a turnover operation.

The abovementioned patents and current technology used for loading and unloading a tire in the tire curing press has drawbacks of higher weight of the assembly due to heavy linear motion arrangement of the paddle (or tire shoe), lack of repeatability due to high wear and tear, lack of easy paddle adjustment mechanism in accuracy, lack of wide bead range and infinite bead diameter adjustment mechanism, complex and larger in size, more number of parts and the like.

Accordingly, there exists a need to provide a chuck assembly for a tire loader which overcomes drawbacks of the prior art.

Objects of the invention

An object of the present invention is to provide a compact and simpler chuck assembly for a tire loader in a tire curing press which can pick up, transport and place a uncured tire from a holder to the mold cavity of the curing press and from mold cavity to the conveyor system with repeated accuracy.

Another object of the present invention is to provide easily adjustable chuck assembly for any bead size while precisely maintaining the concentricity of a paddle with the chuck center.

Yet another object of the present invention is to provide paddle in a chuck assembly which is moving through a circular path in which the concentricity of the paddle with the chuck center is maintained through a slider crank mechanism.

Still another aspect of this invention is to provide paddles in a chuck assembly which are inter connected through adjustable linkages there by making the synchronization of the paddle motion easier with practically less sliding or rolling friction and through adjustable paddles made the easy adjustment of individual paddle with respect to the center of the chuck as well as other paddles possible.

Further object of this invention is to provide a chuck assembly of a tire loader where the paddles are interconnected through linkages thereby eliminating a large number of parts like slide bushes, guided rings and roller as seen in many other available mechanisms.

Furthermore object of the invention is to provide a chuck assembly of tire loader where number of parts is reduced to bare minimum by interconnecting the paddles through linkages thereby providing a mechanism which is compact and less in weight.

One more object of the present invention is to provide light weight and compact chuck assembly for the tire loader which provides a wide range of bead diameter for accommodating a large verity of tires with the possibility of infinite adjustment in the bead diameter.

Another object of the invention is to provide paddles and paddle arms pivot with a center within a slider crank mechanism which stay within the structure of the chuck assembly even in the maximum expanded condition of the paddles.

Yet another object of the present invention is to provide a chuck assembly of tire loader where adjustments for individual paddles to ensure the concentricity of the paddle assembly with chuck center as well as the adjustment for collapsed and extended position of the chuck could be done without involving the dismantling of any part of the chuck assembly.

Summary of the invention

Accordingly, the present invention provides a chuck assembly for loading and unloading a tire in a tire curing press. The chuck assembly comprises a main frame having a guide plate configured along circumference thereof, a plurality of paddles, and a plurality of paddle arms. Each paddle arm of the plurality of paddle arms includes a proximal end connected to a paddle of the plurality of paddles and a distal end connected to the main frame. The chuck assembly further comprises a paddle actuation link capable of moving the plurality of paddle arms in a circular path thereby actuating the plurality of paddles and a plurality of rollers guided in a plurality of slots which holds a plurality of paddles in concentric position. Each roller is fastened to the top of a paddle of the plurality of paddles and guided on a slot of the plurality of slots on a guide plate. The chuck assembly furthermore comprises a plurality of linkages. Each linkage connects one paddle arm to other paddle arm of the plurality of paddle arms thereby providing a synchronized motion of the plurality of paddle arms.. The chuck assembly also comprises of a plurality of length adjustable linkages which provides for individual paddle concentricity adjustment of each paddle of the plurality of paddle by varying pivot length of the plurality of adjustable links.

Brief description of the drawings

Figure 1 shows a top view of a compact chuck assembly for loader and unloader in tire curing press, in accordance with the present invention; and

Figure 2 shows a bottom view of a compact chuck assembly for loader and unloader in tire curing press, in accordance with the present invention; and

Figure 3 shows a paddle arm region of the compact chuck assembly of figure 1. Detailed description of the invention

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.

The present invention provides a chuck assembly for loading and unloading a tire in a tire curing press. The chuck assembly is compact and lighter in weight as compared to existing mechanisms. The slider crank mechanism gives accurate concentricity of paddles with a chuck center. All components of the chuck assembly are rigidly integrated, which provides repeatable accuracy and can be easily adjusted for any bead size within its designed specifications. The chuck assembly of the present invention has provision for individual position adjustment for each paddle so that precise concentricity of the paddle assembly with respect to the chuck centre could be maintained.

Referring now to figure 1 and 2, there is shown a chuck assembly (100) for loading and unloading a tire in a tire curing press, in accordance with the present invention. The chuck assembly (100) includes a main frame (10), a plurality of paddles (20), a plurality of length adjustable linkages (30), a plurality of paddle arms (40), a paddle actuation link (50), and a plurality of linkages (60).

The main frame (10) includes a guide plate (08) configured along circumference thereof. Specifically, the main frame (10) is in circular in shape. The guide plate (08) includes slot (06) configured therein to accommodate the plurality of rollers(22).

The plurality of paddles (20) is arranged on the main frame (10) by the plurality of paddle arms (40) and the plurality of rollers (22) guided on the plurality of slots (06) on the guide plate (08) for holding different bead size tires.

Specifically, the plurality of rollers (22) guided on the plurality of slots (06) on guide plate (08) maintains the plurality of paddles in concentric position. Specifically each roller, for example, roller (22a) of the plurality of rollers (22) is fastened to the top of a paddle (20a) of the plurality of paddles (20) as shown in figure 3. Further, the roller (22a) is movably secured to a slot (06a) of plurality of slots (06) cut of the guide plate (08).

Further, each paddle arm, for example, a paddle arm (40a) of the plurality of paddle arms (40) includes a proximal end (32) pivotally connected to a paddle, for example, the paddle (20a) of the plurality of paddles (20) and a distal end (34) pivotally connected to the main frame (10). Specifically, the proximal end (32) of the of paddle arm (40a) is connected to the paddle, for example, the paddle (20a) of the plurality of paddles (20) through a first pin joint and the distal end (34) of the of paddle arm (40b) is connected to the main frame (10) through a second pin joint.

The plurality of paddle arms (40) are moved by the paddle actuation link (50) in a circular path thereby actuating the plurality of paddles (20). The paddle actuation link (50) is actuated with the help of a cylinder (52). In an embodiment, the paddle actuation link (50) is a fixed extension of the paddle arm of the plurality of paddle arms (40).

The plurality of linkages (60) connects the plurality of paddle arms (40) together. Specifically, each linkage, for example, a linkage (60a) connects one paddle arm, for example, the paddle arm (40a) to other paddle arm, for example, a paddle arm (40b) of the plurality of paddle arms (40) thereby providing a synchronized motion of the plurality of paddle arms (40) when rotated by the paddle actuation link (50).

The plurality of length adjustable linkages (30) provides for individual concentricity adjustment of each paddle of the plurality of paddles (20) by varying a pivot length of the plurality of adjustable links (30).

Specifically, a slider crank mechanism formed by plurality of linkages (60), the plurality of paddle arms (40) , a the plurality of rollers(22) and a plurality of slots (06) guides the plurality of paddles (20) through a concentric path between collapsed and expanded positions.

Further a stud (54), nuts (56), (58) and a stopper (42) are used to position plurality of paddles (20) at infinite bead diameters within the design range in the chuck assembly (100).

Advantages of the invention

1. The chuck assembly (100) is very compact and light compared to existing mechanisms.

2. The slider crank mechanism of the chuck assembly (100) gives accurate concentricity of the paddles with the chuck center.

3. In the chuck assembly (100), all the parts are rigidly integrated, which provides repeatable accuracy.

4. The chuck assembly's (100) slider crank mechanism can be easily adjusted for any bead size within its design specifications.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

We Claim

1. A chuck assembly for loading and unloading a tire in a tire curing press, the chuck assembly comprising:
a main frame having a guide plate configured along circumference thereof;
a plurality of paddles;
a plurality of rollers capable of holding the plurality of paddles in concentric position, each roller of the plurality of rollers is fastened to the top of a paddle of the plurality of paddles and secured on a slot of the plurality of slots made on the guide plate;
a plurality of paddle arms, each paddle arm of the plurality of paddle arms having a proximal end connected to the paddle of the plurality of paddles and a distal end connected to the main frame;
a paddle actuation link capable of moving the plurality of paddle arms in a circular path thereby actuating the plurality of paddles; and
a plurality of linkages, each linkage connecting one paddle arm to other paddle arm of the plurality of paddle arms thereby providing a synchronized motion of the plurality of paddle arms
a plurality of length adjustable linkages provides for individual concentricity adjustment of each paddle of the plurality of paddles by varying pivot length of the plurality of adjustable links.

2. The chuck assembly as claimed in claim 1, wherein the paddle actuation link is a fixed extension of the paddle arm of the plurality of paddle arms.

3. The chuck assembly as claimed in claim 1, wherein the proximal end of the of paddle arm is connected to the paddle of the plurality of paddles through a joint pin and the distal end of the of paddle arm is connected to the main frame through a pin joint.

4. The chuck assembly as claimed in claim 1, wherein the roller of the plurality of the rollers moves through a slot of the plurality of slots cut on the guide plate.