CN219727271U - Heating plate for tyre mould - Google Patents

Abstract

The present utility model provides a tire mold heating plate comprising a flow path having an inlet and an outlet and extending therebetween. The top wall, bottom wall, and side walls at least partially define a flow path. The top wall and the bottom wall are spaced from each other in the axial direction. The flow path has an inward extension and an outward extension in a radial direction and a circumferential extension in a circumferential direction. The circumferential extension is located between the inward extension and the outward extension. The inward extension and the outward extension have a longer length in the radial direction than the circumferential extension. The sidewall has a plurality of recessed sections that are closer to a radially inward end of the flow path than a radially outward end in a radial direction.

Description

Heating plate for tyre mould

Technical Field

The present utility model relates to a heating plate for a tire mold, which can provide heat for vulcanizing a tire during the tire production process. More particularly, the present utility model relates to a heating plate having fluid flow characteristics and other geometric properties to facilitate optimizing heat transfer from the heating plate.

Background

The production of tires includes the step of placing the green tire in a mold during which heat and pressure are applied to the green tire to change its state to a cured state. During the vulcanization process, the green tire is placed inside a metal mold that surrounds the exterior of the green tire. When the green tire is inside the mold, the expandable rubber bladder is disposed inside the green tire and expands to apply pressure to the inner surface of the green tire. The pressure exerted by the expandable bladder causes the green tire to bear against the mold, thereby placing the green tire under pressure. While applying heat and applying a combination of heat and pressure for a specified time completes the curing process. Subsequently, the cured tire is removed from the mold and transported downstream for subsequent processing.

During the curing process, the steam enclosure may be used to provide heat transferred to the tire. However, such a design unnecessarily consumes a large amount of energy, and has a problem of low heating efficiency. These steam jacket arrangements are replaced by heating plates that transfer heat to the tire via conduction. The hot fluid is transported through the heating plate and its heat is transferred from the heating plate to the tyre for vulcanisation. The use of the heating plate improves the energy consumption and efficiency of the vulcanization process of the steam enclosure.

Heating plates for tire molds have been provided with a plurality of baffles that direct the flow of heating fluid through the heating plate. The baffles are arranged to achieve a desired heating profile on the surface of the heating plate for subsequent transfer to the mold or tire. However, the passage of heating fluid through the heating plate causes a pressure loss at the turn, which then would require an increase in energy to complete the heating and thus result in a low heating efficiency. The air flow channels in some heating plates may have large variations in cross-sectional dimensions, thus resulting in pressure loss and again in reduced efficiency. In addition, condensate may accumulate in the air flow channels and impede the flow of heating fluid through the heating plate. This accumulation of condensate will also lead to reduced efficiency in the heat transfer process. Accordingly, there is room for variation and improvement in this field.

Disclosure of Invention

To solve the above-described problems in the prior art, the present utility model provides a heating plate having fluid flow characteristics and other geometric properties to facilitate optimizing heat transfer from the heating plate.

The present utility model provides a heating plate for tire vulcanization, comprising: a central axis extending in an axial direction, a radial direction extending perpendicular to the central axis, and a circumferential direction extending around the central axis; a flow path having an inlet and an outlet and extending from the inlet to the outlet, wherein the top wall, the bottom wall, and the side walls at least partially define the flow path, the top wall and the bottom wall being spaced from each other in an axial direction; wherein the flow path has an inward extension in a radial direction and has an outward extension in a radial direction, the flow path having a circumferential extension in a circumferential direction; wherein the circumferential extension is located between an inward extension and an outward extension, the inward extension and the outward extension having a longer length in a radial direction than the circumferential extension; wherein the flow path has a radially inward end and a radially outward end, wherein the radially inward end is closer to the central axis than the radially outward end in a radial direction, and the sidewall has a plurality of recessed sections that are closer to the radially inward end than the radially outward end in a radial direction.

Preferably, the inwardly extending portion and the outwardly extending portion have components extending in both the radial direction and the circumferential direction.

Preferably, the recessed section is closer to the central axis in the radial direction than said radially outward end in the radial direction.

Preferably, the inlet and outlet are both located at the radially outward end and are spaced from each other in the circumferential direction about the central axis by 20 degrees or less.

Preferably, the side wall has a plurality of portions having a first planar surface facing the flow path and an adjacent second planar surface, the first planar surface being oriented at an angle to the second planar surface such that the angle measured from between the planar surfaces within the flow path is greater than 180 degrees and less than 270 degrees.

Preferably, the convex transition is located between said first planar surface and an adjacent second planar surface.

Preferably, the flow path is the only path configured for the fluid containing heat transfer in the heating plate.

Preferably, two of the plurality of recessed sections are separated from each other by a protruding section of the sidewall.

Preferably, the circumferential extension has a component extending in both the radial direction and the circumferential direction, and the circumferential extension is longer in the circumferential direction than in the radial direction.

Preferably, the bottom wall is inclined such that it has a component extending in the axial direction when the flow path extends from the inlet to the outlet.

Preferably, the distance in the axial direction from the top wall to the bottom wall is from 8 to 30 mm and comprises 8 and 30 mm.

Preferably, the heating plate is located inside the top or bottom mold part of the mold.

Preferably, from 6 to 30 and including 6 and 30 baffles at least partially defining the sidewall are further included, wherein all baffles extend the same length in the circumferential direction along a majority of the length of the baffles in the radial direction.

Preferably, from 6 to 30 and including 6 and 30 baffles at least partially defining the sidewall are further included, wherein some baffles extend in the circumferential direction along a majority of the length of the baffles in the radial direction for a different length than other baffles.

Preferably, the material comprising the heating plate has a thermal conductivity greater than or equal to 35 watts/meter-kelvin, the outer surface of the heating plate configured to engage a mold has a surface roughness of 3.2 microns, and the surface of the heating plate configured to be in contact with a fluid for heat transfer has a surface roughness of 6.3 microns.

Drawings

A full and enabling disclosure of the present utility model, including the best mode thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures in which:

FIG. 1 is a schematic view of a mold with a heating plate in contact with the mold parts.

Fig. 2 is a schematic view of a mold with a heating plate located inside the mold part.

Fig. 3 is a top view of the heating plate.

Fig. 4 is a cross-sectional view taken along line 4-4 of fig. 3.

Fig. 5 is a perspective view of a first component of the heating plate.

Fig. 6 is a top view of the first component of fig. 5.

Fig. 7 is a cross-sectional view taken along line 7-7 of fig. 6.

Fig. 8 is a perspective view of a second component of the heating plate.

Fig. 9 is a top view of the second component of fig. 8.

Fig. 10 is a cross-sectional view taken along line 10-10 of fig. 9.

Fig. 11 is a top view of a heating plate according to various exemplary embodiments.

FIG. 12 is a close-up top view of a portion of a first component of a heating plate showing the flow path through an inward extension and a circumferential extension.

Fig. 13 is a cross-sectional view of an inner portion of the heating plate, showing a downward inclination of the flow path.

Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the utility model.

Detailed Description

Reference will now be made in detail to embodiments of the utility model, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the utility model, and is not intended to limit the utility model. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. The present utility model is intended to include these and other modifications and variations.

A heating plate 10 for providing heat to a tire curing mold 72 is provided. The heating plate 10 may be located in or adjacent to the top or bottom of a mold or press used in the tire manufacturing process. The heating plate 10 has an inlet 22 and an outlet 24 for transporting hot fluid within the flow path 20 of the heating plate 10. The flow path 20 travels through various inward extensions 32 and outward extensions 34, which inward extensions 32 and outward extensions 34 are connected to each other at some point via circumferential extensions 36. The flow path 20 is defined by the top wall 26, the bottom wall 28, and the side wall 30, the side wall 30 having a plurality of recessed sections 48, the recessed sections 48 being closer to the radially inward end 44 than the radially outward end 46 of the flow path 20. The recessed section 48 reduces the pressure drop of the fluid as it travels through the flow path 20, thereby reducing efficiency degradation in the system and improving heat transfer to the heating plate 10. The heating plate 10 may in some cases be provided with a bottom wall 28 having an angle 28 so as to be able to tilt when extending from the inlet 22 to the outlet 24. The angle 28 will assist in the removal of condensate from the flow path 20 and also improve the heat transfer performance of the device.

Referring to FIG. 1, a schematic diagram of a mold 72 is shown. The mold 72 includes an accessory that engages unvulcanized rubber and has molding elements thereon for forming structural features in the tire. The two mold parts are labeled as a top mold part 64 and a bottom mold part 66. The bladder inside the mold 72 provides force to the inside area of the green tire to push the tire against the mold members 64, 66 and other forming members to apply the required force to the tire for curing. In some cases, the mold members 64, 66 themselves may apply a force to the tire, causing the tire to be compressed between the mold members 64, 66 and the bladder. The application of heat supplements the force applied to the green tyre, thereby vulcanizing it, and this heat applied to the tyre may be supplied at least in part by two heating plates, a bottom heating plate 10 engaging the bottom mould part 66 and a top heating plate 11 engaging the top mould part 64. During the curing process, these heating plates 10, 11 provide heat to the mold parts 64, 66, which mold parts 64, 66 in turn transfer heat to the tire.

The heating plates 10, 11 are insulated on their sides facing away from the mould parts 64, 66, so that heat is not wasted. The top cover 82 covers the insulation 84, which insulation 84 in turn engages and insulates the top heating plate 11. The top heating plate 11 may be attached to the top cover 82 such that the top heating plate 11 and the insulation 84 are also moved when the top cover 82 is moved or opened. On the underside of the mould 72, the insulation 74 engages the bottom heating plate 10 to prevent heat loss from the bottom of the mould 72, thereby making the heating process more efficient. A bottom cover 76 of the frame or press may be below the insulation 74 such that the insulation is located between the bottom heating plate 10 and the bottom cover 76. The bottom cover 76 may be moved or remain stationary and, as with the top cover 82, the bottom cover 76 may or may not apply a force to the tire, it being understood that these components of the mold 72 may be variously configured in different mold 72 configurations. The bottom cover 76 may thus be considered part of a molding press or frame in various embodiments.

An alternative arrangement of the mold 72 is shown in the schematic diagram of fig. 2, wherein the top and bottom heating plates 11, 10 are located inside the top and bottom mold parts 64, 66. Other components of the mold 72 are configured identically to those of fig. 1, and no repetition of this information is necessary. The top heating plate 11 inside the top mold part 64 does not engage the heat insulator 84, and if the top mold part 64 itself moves, the top heating plate 11 may move together with the top mold part 64. In this configuration, the top heating plate 11 may not be attached to the top cover 82, such that the top heating plate 11 does not move when the top cover 82 and attached insulation 84 are opened or removed. Placing the top heating plate 11 inside the top mold part 64 reduces the overall height of the mold 72 compared to the fig. 1 configuration, whereby this configuration requires less space, in which the top heating plate 11 is instead located above and engaged with the top mold part 64, increasing the overall height of the mold 72. Placing the bottom heating plate 10 within the bottom mold part 66 also saves space at the level of the mold 72 compared to the embodiment of fig. 1, where the bottom heating plate 10 is located below the bottom mold part 66 and engages the bottom mold part 66 and the insulation 74. The disclosed heating plates 10, 11 may be used in a variety of mold 72 configurations, with the understanding that those disclosures are only some of the possible configurations.

Referring to fig. 3-10, an exemplary embodiment of the heating plate 10 is shown. The heating plate 10 is a bottom heating plate but may also be used as a top heating plate in the mold 72. The heating plate 10 has an opening through which the central axis 12 extends. The opening may be for receiving a bladder of the mold 72 or may be present because the area would pass through the central opening of the tire and need not be heated during tire curing. The heating plate 10 extends around the central axis 12 in the circumferential direction 18 and may in some cases extend practically completely 360 degrees around the central axis 12. The radial direction 16 of the heating plate 10 extends outwards from the central axis 12 so as to be perpendicular to the central axis 12. The heating plate 10 functions to contain the heated fluid and to transport the heated fluid through and out of the heating plate 10 such that heat from the heated fluid is transferred to the heating plate 10 and subsequently out of the heating plate 10 and to the mold sections 64, 66 for heating the mold 72. The fluid transported through the heating plate 10 may be oil, water, steam and water or any other type of heat transfer fluid. The heating fluid may be a gas or a liquid, or may be a gas/liquid combination.

Heating fluid is introduced to the heating plate 10 via an inlet 22 and moves through a flow path 20, said flow path 20 being defined by the heating plate 10. The flow path 20 terminates at an outlet 24 and the heating fluid exits the heating plate 10 from the outlet 24. During this transfer process, heat from the heating fluid is removed and absorbed by the material of the heating plate 10, thereby heating the heating plate 10 and subsequently the mold 72 again. The inlet 22 and the outlet 24 are arranged close to each other in the circumferential direction 18, and their distance from each other in the circumferential direction 18 is denoted as the interval 50. The spacing 50 is 20 degrees or less in the circumferential direction 18 about the central axis 12. In other embodiments, the spacing 50 is 25 degrees or less, 30 degrees or less, 35 degrees or less, 10 degrees or less, or 15 degrees or less in the circumferential direction 18 about the central axis 12. The inlet 22 and the outlet 24 may be arranged such that they share the same position in the circumferential direction 18 about the central axis 12 such that the spacing 50 is 0 degrees. In these cases, the inlet 22 and the outlet 24 may be located at different positions in the axial direction 14.

The heating plate 10 includes a plurality of baffles 68 and the flow path 20 must extend around the baffles 68 to establish a desired heat transfer profile on the heating plate 10. Fifteen baffles 68 are present, but from 6 to 30 (and including 6 and 30) baffles 68 may be present in other embodiments. The heating fluid enters the flow path 20 via the inlet 22 and into the inward extension 32 of the flow path 20. The heating fluid here extends in the radial direction 16 towards the central axis 12 and to a circumferential extension 36 of the flow path 20, the circumferential extension 36 of the flow path 20 being oriented mainly in the circumferential direction 18. The heating fluid then flows to the outwardly extending portion 34 of the flow path 20 and outwardly in the radial direction 16, thereby flowing around the baffle 68. The heating fluid will then flow to the subsequent inward extension 32 and around the subsequent baffle 68, and this process will repeat until the heating fluid reaches the outlet 24, where the heating fluid will be removed from the heating plate 10.

While described as an inward extension 32 and an outward extension 34, it should be understood that these extensions 32, 34 may have components that extend in both the radial direction 16 and the circumferential direction 18, and need not extend only in the radial direction 16. However, the length extending in the radial direction 16 may be longer than the length extending in the circumferential direction 18. When described as a circumferential extension 36, this is the case: the circumferential extension 36 may have a component that extends in both the radial direction 16 and the circumferential direction 18, although the circumferential extension 36 may extend longer in the circumferential direction 18 than the radial direction 16. The heating plate 10 may be arranged such that only a single flow path 20 is present in the heating plate 10, such that no additional flow path is present in the heating plate 10 other than the single flow path 20. In this regard, the heating fluid within the heating plate 10 has only a single flow path 20 through which it can flow.

The heating plate 10 is configured to withstand pressure and includes a plurality of features 88 configured to carry the load. The feature 88 may also be the baffle 68 in various embodiments and may partially define the flow path 20. Features 86 are also provided to enable the heater plate 10 to be properly positioned in the mold 72 to orient it in the correct position.

Referring particularly to fig. 4, the heating plate 10 is shown having a longer length in a radial direction 16 than an axial direction 14, the axial direction 14 being parallel to the central axis 12. The cross-sectional view passes through the circumferential extension 36, and the flow path 20 is defined by the top wall 26, the bottom wall 28, and the side walls 30 and has a rectangular cross-sectional shape. The top wall 26 and the bottom wall 28 are spaced from each other in the axial direction 14 and have flat surfaces. The side walls 30 are perpendicular to the top and bottom walls 26, 28 and have two sections spaced from each other longer than the distance from the top wall 26 to the bottom wall 28. The entire flow path 20 may have a rectangular cross-sectional shape. In some embodiments, the length of the air flow path 20 in the circumferential direction 18 is greater at all points than the length of the air flow path 20 in the axial direction 14. This is not the case in yet other embodiments, and in yet further embodiments the cross-sectional shape of the flow path 20 is not rectangular. The heating plate 10 may be constructed of one or more pieces, and as shown, the heating plate 10 includes a first piece 78 and an attached second piece 80. The second member 80 defines the top wall 26 of the flow path 20 and the first member 78 defines both the bottom wall 28 and the side wall 30. The height of the flow path 20 may be defined as the length of the flow path 20 in the axial direction 14, and may be from 8 to 30 millimeters and include 8 to 30 millimeters. In this regard, the top wall 26 to the bottom wall 28 may be 8 to 30 millimeters and include 8 to 30 millimeters.

Fig. 5 to 7 show a first part 78 of the heating plate 10. The inward extension 32 of the flow path 20 has a length 38 extending in the radial direction 16 and the outward extension 34 has a length 40 in the radial direction 16. These lengths 38, 40 may be equal to each other. The circumferential extension 36 of the flow path 20 has a length 42 in the radial direction 16. Length 42 is less than length 38 and length 42 is likewise less than length 40. The lengths 38, 40 may be greater than the circumferential lengths of the inward extension 32 and the outward extension 34 in the circumferential direction 18. The length 42 may be less than the length of the circumferential extension 36 in the circumferential direction 18.

The side wall 30 has a recessed section 48, which recessed section 48 is closer to the radially inward end 44 in the radial direction 16 than the radially outward end 46 in the radial direction 16. The heating fluid flowing radially inwardly through the flow path 20 in the inward extension will be directed by the recessed section 48, transitioning to flow in the circumferential direction 18. The recessed section 48 will minimize or reduce swirl flow at this section of the flow path 20, thereby improving the efficiency of the heating plate 10 and reducing pressure losses when passing therethrough. Due to the presence of the individual recessed sections 48, less energy is required to heat the fluid through the heating plate 10 and heat transfer from the heating plate 10 to the mold 72 is improved. The recessed section 48 is recessed with respect to an axis extending in the axial direction 14. Any number of recessed sections 48 may be present in the flow path 20. As shown, sixteen recessed sections 48 are present, but any number is possible in other forms of the flow path 20.

After passing through the recessed section 48, the heating fluid will flow past the protruding section 60 of the sidewall 30. The protruding section 60 is located at the radially inward end 44 and is protruding with respect to an axis parallel to the central axis 12. The protruding section 60 continues to direct the heating fluid through the flow path 20 in a stable manner without creating a pressure drop. In other designs, the protruding section 60 is not present, and the straight section of the sidewall 30 is located at this location for guiding the flow of the heating fluid. After flowing past the convex section 60, the heating fluid engages the subsequent concave section 48 of the sidewall 30 on the adjacent baffle 68. In this regard, the protruding section 60 is located between the two recessed sections 48 at the radially inward end 44, thereby facilitating the flow of the heating fluid through the flow path 20. This design improves the efficiency of the heating plate 10. In other arrangements, two recessed sections 48 are joined to one another, and no protruding section 60 or any other section of sidewall 30 is present between adjacent recessed sections 48.

The flow path 20 includes other features that enhance fluid flow to optimize efficiency during heat exchange. The sidewall 30 at the baffle 68 has a first planar surface 52 and a second planar surface 54. The second planar surface 54 is closer to the central axis 12 in the radial direction 16 than the first planar surface 52 is to the central axis 12 in the radial direction 16. The two planar surfaces 52, 54 are oriented at an angle 56 to one another, wherein the angle 56 is greater than 180 degrees and less than 270 degrees measured within the flow path 20. In this regard, "measured within the flow path" refers to an angular measurement that extends from the first planar surface 52 to the flow path 20 and then to the second planar surface 54. In a preferred embodiment, angle 56 is 110 degrees. The angle 56 facilitates the transport of the heating fluid along the flow path 20, thereby reducing pressure and improving heat transfer efficiency.

The first and second planar surfaces 52, 54 may form a portion of the inward extension 32 and/or the circumferential extension 36. On opposite sides of the baffle 68, the side walls 30 may be configured in a similar manner, with the two planar surfaces oriented at similar angles to each other. The straight or convex sections of the sidewall 30 may be located radially inward of the flow path 20 in the circumferential extension 36. It should be appreciated that the flow paths 20 extend around the baffles 68 such that the flow paths 20 are inward in the radial direction 16 from some baffles 68 and outward in the radial direction 16 from other baffles 68. The foregoing arrangement of planar surfaces 52, 54 may thus be applied to some of baffles 68, but not all of baffles 68. In other arrangements, the angle 56 is not present in the heating plate 10. The baffle 68 has a length 70 in the circumferential direction 18. The length 70 may be the distance in the circumferential direction 18 from the first planar surface 52 to the oppositely disposed first planar surface 52 on the same baffle 68. The length 70 of all baffles 68 may be the same as one another. This same length 70 can be described as: the same length 70 extends the same along most of the length of the baffle 68 in the radial direction 16. The cross-sectional shape of the flow path 20 is rectangular and the width at different points in the flow path 20 may vary. In this regard, the height, which is the distance in the axial direction 14 from the top wall 26 to the bottom wall 28, cannot be changed at all at any point in the flow path 20, but the width between the side walls 30 may actually be changed. Although the width (and thus the size) of the flow path 20 may vary at different points in the flow path 20, the cross-sectional shape of the flow path 20 remains rectangular. The side wall 30 may be a single continuous wall extending from the inlet 22 to the outlet 24 and back, and may be described in the context of the cross-sectional area of the flow path 20 as two walls.

Fig. 8-10 show a second piece 80 attached to the first piece 78 to form the heating plate 10. The second member 80 has a smaller length in the axial direction 14 than the length of the first member 78 in the axial direction 14. The second member 80 has an opening for receiving the baffle 68 to enable the feature 86 to be exposed to support the heating plate 10 when a force is applied thereto during the curing process. The second member 80 forms the top wall 26 of the flow path 20. Although shown as being constructed from two primary components (first component 78 and second component 80), any number of components may be used to construct heating plate 10. The components 78, 80 may be attached to each other by bolts, welding, a combination of both, mechanical fasteners, or by other forms of attachment.

An alternative embodiment of the heating plate 10 is shown in fig. 11. The heating plate may be the top heating plate 11 of the mould 72, but may also be used as a bottom heating plate in other moulds 72. Features previously described, such as the concave section 48, the convex section 60, the planar surfaces 52, 54 oriented at the angle 56, and the single flow path 20 between the inlet 22 and the outlet 24, may be the same as previously described, and this information need not be repeated. The heating plate 10 of fig. 11 is different in that: the length 70 of some baffles 68 is different from the length 70 of other baffles 68. In this regard, the length 70 is defined as the distance in the circumferential direction 18 from the first planar surface 52 of one of the baffles 68 to the other first planar surface 52 thereof along a majority of the length of the baffle 68 in the radial direction 16. The four baffles 68 have the same length 70 and eleven baffles 68 have the same length 70, but the same length 70 of eleven baffles 68 is shorter than the four baffles 68 previously mentioned. Two baffles 68 having a greater length 70 are arranged with features 86 interposed therebetween. The other two baffles 68 having the same greater length 70 have one of the baffles 68 of lesser length 70 therebetween, with the remaining smaller length baffles 68 being evenly distributed between the two sets of baffles 68 of greater length 70.

Fig. 12 is a close-up top view of a portion of the first component 78 showing the flow path 20 upon entering the first component 78 via the inlet 22. As previously discussed, the first planar surface 52 is oriented at an angle 56 to the second planar surface 54, and may be 180 to 270 degrees, as measured by measuring the angle through the flow path 20. However, the planar surfaces 52, 54 do not engage each other. The raised transition 58 is located between and engages the first planar surface 52 and the second planar surface 54. The second planar surface 54 terminates at a portion of the sidewall 30 disposed approximately 270 degrees relative to the first planar surface 52 and is a straight section of the sidewall 30. The second planar surface 54 may be disposed opposite the recessed section 48 and directly facing the recessed section 48. The flow path 20 may be arranged to: such that the straight section of the sidewall 30 extends from the recessed section 48 and is located at the radially inward end 44. The linear section may be parallel to the linear section of the sidewall 30 described above such that the length 42 extends therebetween. Length 38 may extend from radially outward end 46 to an axis of radius of curvature of recessed section 48.

Fig. 13 is a cross-sectional view of a portion of the heating plate 10 showing the flow path 20. During use of the heating plate 10, condensate may accumulate in the flow path 20, which may interfere with its function. To assist in the removal of condensate from the flow path 20, the bottom wall 28 may be angled relative to the axial direction 14 such that it is not perpendicular to the axial direction 14. In this regard, the angle 62 may be measured from the bottom wall 28 to a line parallel to the radial direction 16. As the flow path 20 extends from the inlet 22 to the outlet 24, the bottom wall 28 will thus have a component of its extension in the axial direction 14. The angle 62 may be referred to as the slope of the bottom wall 28 and may extend entirely from the inlet 22 to the outlet 24, and the slope may remain uniform at all points along its path from the inlet 22 to the outlet 24. In other cases, the angle 62 may vary at different points along the flow path 20, and at some points the angle 62 may be zero. According to various embodiments, the angle 62 may be 0.5 degrees, 6 degrees, 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 0.5 to 2.5 degrees, 0.5 to 6 degrees, 2.5 to 4.5 degrees, or 4.5 to 6 degrees. The angle 62 is optional and need not be present in all forms of the heating plate 10. When provided with the angle 62, the outlet 24 is located at a lower point in the axial direction 14 than the inlet 22. The angle 62 will assist in allowing condensate to flow down the bottom wall 28 and out of the heater plate 10.

Having a sufficient number of baffles 68 to adjust the configuration of the flow path 20 helps to heat uniformity of the heating plate 10 and can minimize temperature asymmetry of the heating plate 10. This arrangement enables to control the vulcanisation process by acting only on the heat required for the zone to be vulcanised. The surface of the first part 78 or the second part 80 that is in contact with the mold 72 may have a surface roughness of 3.2 micrometers (micrometers). This amount of roughness can maximize the heat exchange between the heating plate 10 and the mold 72. The surfaces of the top wall 26, bottom wall 28, and side walls 30 that are in contact with the heating fluid may have a surface roughness of 6.3 microns to facilitate fluid circulation to increase flow rates. In the case where the heating fluid is steam or water, condensate is more easily expelled from the flow path when the surface roughness of the walls 26, 28, 30 is 6.3 microns. The materials comprising the first and second members 78, 80 may have a thermal conductivity greater than or equal to 35 watts/meter-kelvin to achieve the desired heat transfer.

The heating plate 10 and its flow path 20 should be designed to maximize heat flow. This can reduce the time the tire is in the hot press, which increases the productivity of the tire manufacturing process. In order to maximize heat flow, the distance between the flow path 20 and the enclosure to be heated should be minimized. The exchange surface between the heating plate 10 and the die 72 should be as large as possible and the same logic applies to the surfaces 26, 28, 30 of the flow path 20 that are in contact with the heating fluid. The preheating time of the die 72 may be reduced to achieve an efficiency gain and once the target temperature is reached, the heating to the set point may be adjusted so that only the heat loss requires additional heat to bring the die 72 back to the operating temperature. The disclosed features such as the recessed section 48 and the angle 56 facilitate fluid flow and thereby improve the heat transfer process.

While the utility model has been described in connection with certain preferred embodiments, it is to be understood that the subject matter encompassed by way of the utility model is not limited to those specific embodiments. On the contrary, the subject matter of the present utility model is intended to cover all alternatives, modifications and equivalents that may be included within the spirit and scope of the claims.

Claims (15)

1. A tire mold heating plate, comprising:

a central axis extending in an axial direction, a radial direction extending perpendicular to the central axis, and a circumferential direction extending around the central axis;

a flow path having an inlet and an outlet and extending from the inlet to the outlet, wherein the top wall, the bottom wall, and the side walls at least partially define the flow path, the top wall and the bottom wall being spaced from each other in an axial direction;

wherein the flow path has an inward extension in a radial direction and has an outward extension in a radial direction, the flow path having a circumferential extension in a circumferential direction;

wherein the circumferential extension is located between an inward extension and an outward extension, the inward extension and the outward extension having a longer length in a radial direction than the circumferential extension;

wherein the flow path has a radially inward end and a radially outward end, wherein the radially inward end is closer to the central axis than the radially outward end in a radial direction, and the sidewall has a plurality of recessed sections that are closer to the radially inward end than the radially outward end in a radial direction.

2. The tire mold heating plate of claim 1, wherein the inward extension and the outward extension have components extending in both radial and circumferential directions.

3. Tyre mould heating plate according to claim 1 or 2, wherein the recessed section is radially closer to the central axis than the radially outer end in the radial direction.

4. The tire mold heating plate of claim 1, wherein the inlet and outlet are both located at radially outward ends and the inlet and outlet are spaced 20 degrees or less from each other about a central axis in a circumferential direction.

5. The tire mold heating plate of claim 1, wherein the sidewall has a plurality of portions having a first planar surface facing the flow path and an adjacent second planar surface, the first planar surface oriented at an angle to the second planar surface such that an angle measured from between the planar surfaces within the flow path is greater than 180 degrees and less than 270 degrees.

6. The tire mold heating plate of claim 5, wherein a raised transition is located between the first planar surface and an adjacent second planar surface.

7. The tire mold heating plate of claim 1, wherein the flow path is the only path configured for fluid containing heat transfer in the heating plate.

8. The tire mold heating plate of claim 1, wherein,

two of the plurality of recessed sections are separated from each other by a protruding section of the sidewall.

9. The tire mold heating plate of claim 1, wherein the circumferential extension has a component extending in both a radial direction and a circumferential direction, and the circumferential extension is longer in the circumferential direction than in the radial direction.

10. The tire mold heating plate of claim 1, wherein the bottom wall is sloped such that the bottom wall has a component extending in an axial direction as the flow path extends from the inlet to the outlet.

11. The tire mold heating plate of claim 1, wherein the distance in the axial direction from the top wall to the bottom wall is from 8 to 30 millimeters and includes 8 and 30 millimeters.

12. The tire mold heating plate of claim 1, wherein the heating plate is located inside a top mold part or a bottom mold part of a mold.

13. The tire mold heating plate of claim 1, further comprising from 6 to 30 baffles at least partially defining the sidewall and including 6 and 30 baffles, wherein all baffles extend the same length in the circumferential direction along a majority of the length of the baffles in the radial direction.

14. The tire mold heating plate of claim 1, further comprising from 6 to 30 baffles and including 6 and 30 baffles at least partially defining the sidewall, wherein some baffles extend in a circumferential direction along a majority of the length of a baffle in a radial direction for a different length than other baffles.

15. The tire mold heating plate of claim 1, wherein the material comprising the heating plate has a thermal conductivity greater than or equal to 35 watts/meter-kelvin, the outer surface of the heating plate configured to engage a mold has a surface roughness of 3.2 microns, and the surface of the heating plate configured to contact a fluid for heat transfer has a surface roughness of 6.3 microns.