Design Methodology

Abstract

This invention provides a design method that allows for the precise placement of vent holes in a short amount of time. [Solution] The present invention is a design method for arranging vent holes 2 in a vulcanization molding die 1 for a tire T. The vulcanization molding die 1 includes a plurality of pitch P pattern components 3 corresponding to the tread pattern of the tire T. In the vulcanization molding die 1, the arrangement of holes 2 for a representative pitch P1, which is one of the plurality of pitches P, is set, thereby setting the arrangement of all holes 2 for the plurality of pitches P.

Description

Technical Field

[0001] The present invention relates to a design method for arranging vent holes in a mold for vulcanizing and molding tires.

Background Art

[0002] In a mold for vulcanizing and molding tires, vent holes for discharging air during vulcanizing and molding are arranged. For example, Patent Document 1 below proposes a vulcanizing mold that can suppress clogging of the vent passage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to mainly improve noise performance, it has been common practice to use pattern components with different pitches as the tread pattern of a tire. The arrangement of vent holes needs to be set for each of a plurality of pitches, which has required a great deal of design time. In particular, in recent years, spring vents and vent pieces are often adopted, and since the amount of air discharged is restricted, it has been necessary to arrange a large number of vent holes, and the design time has tended to increase further.

[0005] The present invention has been devised in view of the above actual situation, and the main object thereof is to provide a design method capable of accurately setting the arrangement of vent holes in a short time.

Means for Solving the Problems

[0006] The present invention relates to a design method for arranging vent holes in a mold for vulcanizing a tire, wherein the vulcanizing mold includes a plurality of pitch pattern components corresponding to the tread pattern of the tire, and the design method involves setting the arrangement of the holes for a representative pitch, which is one of the plurality of pitches, in the vulcanizing mold, thereby setting the arrangement of all the holes for the plurality of pitches. [Effects of the Invention]

[0007] The design method of the present invention, by having the above-described configuration, allows for the precise arrangement of vent holes to be set in a short amount of time. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view of a vulcanizing mold set up by the design method of the present invention. [Figure 2] This is a partial unfolded view of the first mold, showing an example of a pattern component. [Figure 3] This is a partial diagram showing the pattern components of a representative pitch. [Figure 4] This is a partial unfolded diagram showing the arrangement of holes at a typical pitch. [Figure 5] This is a partial unfolded view showing the arrangement of the holes for the second pitch. [Figure 6] This is a flowchart of the design method. [Figure 7] This is a flowchart of the second step. [Figure 8] This is the flowchart for the third step. [Figure 9] This is a partial unfolded diagram showing the arrangement of holes of various pitches, representing a typical size. [Figure 10] This is a partial unfolded view showing the arrangement of holes of the second size with multiple pitches. [Modes for carrying out the invention]

[0009] One embodiment of the present invention will be described in detail below with reference to the drawings. Figure 1 is a cross-sectional view of the vulcanization mold 1 as set out by the design method of this embodiment. As shown in Figure 1, the vulcanization mold 1 for tire T is provided with a number of vent holes 2 for releasing air during the vulcanization molding of tire T. Such a vulcanization mold 1 can release air during vulcanization molding and suppress molding defects.

[0010] The vulcanization molding die 1 includes, for example, a first die 1A for molding the tread portion of a tire T, and a pair of second dies 1B for molding the sidewall portion. It is preferable that the vent holes 2 are located in the first die 1A and the second die 1B. The design method of this embodiment is a method for arranging the vent holes 2 in the first die 1A of the vulcanization molding die 1 for a tire T.

[0011] Figure 2 is a partially unfolded view of the first mold 1A showing an example of a pattern component 3. As shown in Figure 2, the first mold 1A of the vulcanization molding mold 1 of this embodiment includes a plurality of pattern component 3 with pitches P corresponding to the tread pattern (not shown) of the tire T. In Figure 2, for illustrative purposes, a pitch P with a constant width W1 in the tire axial direction is shown as an example, but the embodiment is not limited to this, and can be applied to various pitches P as long as the pitch P corresponds to the tread pattern of the tire T.

[0012] The pattern component 3 preferably consists of multiple pitches P with different pitch lengths arranged randomly. A tire T formed with such a vulcanizing mold 1 can suppress the generation of noise at specific frequencies and improve noise performance.

[0013] Figure 3 is a partially unfolded view showing a pattern component 3 with a representative pitch P1. As shown in Figure 3, the vulcanization mold 1 includes, for example, a pattern component 3 corresponding to at least one of the lateral grooves and sipes of the tire T.

[0014] At a plurality of pitches P with different pitch lengths, it is common for the relative distances between the pattern components 3 to be different. On the other hand, the vent holes 2 are not necessarily arranged in proportion to the relative distances between the pattern components 3. Therefore, in order to arrange the holes 2 at optimal positions with respect to the pattern components 3, it was necessary to individually set all the holes 2 at a plurality of pitches P.

[0015] FIG. 4 is a partial development view showing the arrangement of the holes 2 at the representative pitch P1, and FIG. 5 is a partial development view showing the arrangement of the holes 2 at the second pitch P2. As shown in FIGS. 4 and 5, the design method of the present embodiment is such that, in the vulcanization molding die 1, by setting the arrangement of the holes 2 at the representative pitch P1, which is one of the plurality of pitches P, the arrangements of all the holes 2 at the plurality of pitches P are set.

[0016] Such a design method does not require individually setting the arrangements of all the holes 2 at a plurality of pitches P, and can shorten the design time. Therefore, the design method of the present embodiment can accurately set the arrangement of the vent holes 2 in a short time.

[0017] In a more preferred aspect, while referring to FIGS. 1 to 5, the specific steps of the design method will be described. FIG. 6 is a flowchart of the design method of the present embodiment. As shown in FIG. 6, in the design method of the present embodiment, first, a first step S1 of setting a development rule for arranging the holes 2 is performed. The development rule is preferably set by an operator. The development rule may be set by a computer based on, for example, the big data of the vulcanization molding die 1 up to now.

[0018] The development rule is set with setting conditions such as, for example, whether the parameters related to the arrangement of the holes 2 are variables that change according to changes in the pitch P and the width W1, or constants that do not change. Such a development rule helps to develop the arrangement of the holes 2 at the representative pitch P1 to the arrangements of all the holes 2 at a plurality of pitches P other than the representative pitch P1.

[0019] In the design method of this embodiment, following the first step S1, a second step S2 is performed to set the arrangement of the holes 2. Figure 7 is a flowchart of the second step S2. As shown in Figure 7, the second step S2 of this embodiment first involves an input step S21 in which pattern data of the tread pattern of the tire T is acquired. It is desirable that the pattern data be automatically acquired by a computer by inputting the design data of the tire T.

[0020] If each of the multiple pitches P contains multiple pattern component 3, for example, it may become unclear which pattern component 3 of the representative pitch P1 corresponds to the pattern component 3 of the second pitch P2, which is different from the representative pitch P1. In other words, there is a risk that the corresponding pattern component 3 may be misrecognized for multiple pitches P.

[0021] In this embodiment, the second step S2 is an area setting step S22 in which an area 4 is set for identifying the pattern component 3 of the representative pitch P1. Since area 4 is set in such an area setting step S22, misrecognition of the corresponding pattern component 3 can be suppressed.

[0022] Figure 3 illustrates a case where the pattern component 3 includes a first element 3a and a second element 3b. In the area setting step S22, for example, area 4 is set as a first area 4a including the first element 3a and a second area 4b including the second element 3b. Area 4 is preferably set manually by an operator. Area 4 may also be set automatically by a computer based on the pattern component 3, for example.

[0023] Figure 3 illustrates an area 4 that divides the pitch P in the circumferential direction of the tire. However, area 4 is not limited to this configuration and may also be divided in the axial direction of the tire, for example. Furthermore, area 4 does not necessarily have to include pattern components 3, and may include multiple pattern components 3 as long as different pattern components 3 can be individually recognized.

[0024] In this embodiment, the second step S2, following the area setting step S22, is a identification step S23 in which pattern component 3 is identified in area 4 of the representative pitch P1. The identification step S23 identifies, for example, the first element 3a of the first area 4a and the second element 3b of the second area 4b. It is desirable that the pattern component 3 included in area 4 be identified automatically by a computer. The pattern component 3 included in area 4 may also be identified manually by an operator, for example, or the operator may modify what has been identified by the computer.

[0025] In this embodiment, the second step S2, following the specific step S23, is a hole setting step S24 in which the arrangement of holes 2 in area 4 is set. Preferably, the arrangement of holes 2 in area 4 is set manually by an operator. The arrangement of holes 2 in area 4 may be set automatically by a computer, for example, or the arrangement set by the computer may be modified by an operator.

[0026] Figure 4 illustrates a case in which the holes 2 set at the representative pitch P1 include the first holes 2a and 2b located in the first area 4a, and the third holes 2c and 4th holes 2d located in the second area 4b.

[0027] In this embodiment, hole 2 corresponds to at least one of a vent hole, a vent piece, and a spring vent. The vent hole helps reduce the manufacturing and maintenance costs of the vulcanization molding die 1 because it does not require other components. The vent piece helps reduce the amount of rubber entering hole 2 because it can restrict the flow rate of the exhausted air. The spring vent can suppress the entry of rubber into hole 2 because it can close the valve when rubber pressure is applied.

[0028] The inner diameter r of the hole 2 provided in the vulcanization mold 1 is preferably 0.1 mm or more. Having an inner diameter r of 0.1 mm or more ensures that air inside the vulcanization mold 1 can be reliably discharged during the vulcanization molding of the tire T. From this viewpoint, the inner diameter r of the hole 2 is more preferably 0.2 mm or more, and even more preferably 0.3 mm or more.

[0029] The inner diameter r of the hole 2 provided in the vulcanization mold 1 is preferably 5.0 mm or less. By having an inner diameter r of 5.0 mm or less, the amount of rubber that enters the inside of the hole 2 during the vulcanization molding of the tire T can be reduced. From this viewpoint, the inner diameter r of the hole 2 is more preferably 2.0 mm or less, and even more preferably 1.5 mm or less.

[0030] Based on these considerations, the inner diameter r of the hole 2 provided in the vulcanization mold 1 is preferably 0.1 to 5.0 mm, more preferably 0.2 to 2.0 mm, and even more preferably 0.3 to 1.5 mm. The combination of the upper and lower limits within these numerical ranges can be arbitrarily selected.

[0031] Preferably, there is one or more holes 2 in area 4. Having one or more holes 2 in area 4 ensures that air near area 4 is reliably discharged. From this viewpoint, more preferably, there are two or more holes 2 in area 4, and even more preferably, three or more.

[0032] The number of holes 2 arranged in area 4 is preferably 200 or less. Having 200 or fewer holes 2 in area 4 helps to prevent area 4 from becoming excessively large and helps to suppress misrecognition of pattern components 3. From this viewpoint, the number of holes 2 arranged in area 4 is more preferably 100 or less, and even more preferably 50 or less.

[0033] Based on these considerations, the number of holes 2 arranged in area 4 is preferably 1 to 200, more preferably 2 to 100, and even more preferably 3 to 50. The combination of the upper and lower limits within these numerical ranges can be arbitrarily selected.

[0034] In this embodiment, the second step S2, following the hole setting step S24, is an acquisition step S25 in which parameters related to the development rules for the arrangement of holes 2 in area 4 are acquired. It is desirable that the parameters related to the development rules for the arrangement of holes 2 be automatically identified by a computer. Such an acquisition step S25 is useful for expanding the arrangement of holes 2 at a representative pitch P1 to multiple pitches P other than the representative pitch P1.

[0035] Parameters in the first area 4a include, for example, the first distance L1, second distance L2, third distance L3, and fourth distance L4 relating to the first hole 2a and the second hole 2b. Here, the first distance L1 is the distance in the tire axis direction between the center of the first hole 2a and the edge 4c of the first area 4a. The second distance L2 is the distance in the tire circumferential direction between the center of the first hole 2a and the first element 3a. The third distance L3 is the distance in the tire axis direction between the center of the second hole 2b and the edge 4c of the first area 4a. The fourth distance L4 is the distance in the tire circumferential direction between the center of the second hole 2b and the first element 3a.

[0036] Parameters in the second area 4b include, for example, the fifth distance L5, sixth distance L6, seventh distance L7, and eighth distance L8 with respect to the third hole 2c and fourth hole 2d. Here, the fifth distance L5 is the distance in the tire axis direction between the center of the third hole 2c and the edge 4c of the second area 4b. The sixth distance L6 is the distance in the tire circumferential direction between the center of the third hole 2c and the second element 3b. The seventh distance L7 is the distance in the tire axis direction between the center of the fourth hole 2d and the edge 4c of the second area 4b. The eighth distance L8 is the distance in the tire circumferential direction between the center of the fourth hole 2d and the second element 3b.

[0037] In this embodiment, the second step S2, following the acquisition step S25, is an unfolding step S26 in which unfolding rules are applied to multiple pitches P other than the representative pitch P1 to set the arrangement of holes 2. Figure 5 illustrates a second pitch P2, which has a pitch length greater than the representative pitch P1, as one of the multiple pitches P other than the representative pitch P1.

[0038] In Figure 5, the second pitch P2 has the same arrangement as the representative pitch P1, with the first hole 2a, second hole 2b, third hole 2c, and fourth hole 2d. Parameters in the first area 4a of the second pitch P2 include, for example, the ninth distance L9, tenth distance L10, eleventh distance L11, and twelfth distance L12 relating to the first hole 2a and the second hole 2b.

[0039] Here, the 9th distance L9 of the second pitch P2 is the parameter corresponding to the 1st distance L1 of the representative pitch P1. The 10th distance L10 of the second pitch P2 is the parameter corresponding to the 2nd distance L2 of the representative pitch P1. The 11th distance L11 of the second pitch P2 is the parameter corresponding to the 3rd distance L3 of the representative pitch P1. The 12th distance L12 of the second pitch P2 is the parameter corresponding to the 4th distance L4 of the representative pitch P1.

[0040] Parameters in the second area 4b of the second pitch P2 include, for example, the 13th distance L13, the 14th distance L14, the 15th distance L15, and the 16th distance L16 with respect to the 3rd hole 2c and the 4th hole 2d.

[0041] Here, the 13th distance L13 of the second pitch P2 is the parameter corresponding to the 5th distance L5 of the representative pitch P1. The 14th distance L14 of the second pitch P2 is the parameter corresponding to the 6th distance L6 of the representative pitch P1. The 15th distance L15 of the second pitch P2 is the parameter corresponding to the 7th distance L7 of the representative pitch P1. The 16th distance L16 of the second pitch P2 is the parameter corresponding to the 8th distance L8 of the representative pitch P1.

[0042] The development rule in this embodiment is a setting condition for parametrically developing the parameters of the arrangement of holes 2 in area 4. For example, the development rule sets the parameters of the first hole 2a and the third hole 2c as constants that are not linked to the pitch P, and sets the parameters of the second hole 2b and the fourth hole 2d as variables that vary proportionally to the pitch P. Such a development rule can be parametrically developed so that the arrangement of holes 2 is optimized when the pitch P is changed.

[0043] In this case, according to the expansion rules, the 9th distance L9 and 10th distance L10 of the second pitch P2 are equal to the 1st distance L1 and 2nd distance L2 of the representative pitch P1, respectively. On the other hand, the 11th distance L11 and 12th distance L12 of the second pitch P2 are greater than the 3rd distance L3 and 4th distance L4 of the representative pitch P1, respectively.

[0044] Similarly, the 13th distance L13 and the 14th distance L14 of the second pitch P2 are equal to the 5th distance L5 and the 6th distance L6 of the representative pitch P1, respectively. On the other hand, the 15th distance L15 and the 16th distance L16 of the second pitch P2 are greater than the 7th distance L7 and the 8th distance L8 of the representative pitch P1, respectively.

[0045] In the deployment rule of this embodiment, the inner diameter r of hole 2 is set as a constant that is not linked to the pitch P. Such a deployment rule allows for the commonization of vent pieces and spring vents provided in hole 2, which helps to reduce manufacturing costs.

[0046] The unfolding rules are not limited to this form, and various setting conditions for parametric unfolding can be adopted. In this design method, by setting the arrangement of holes 2 at a representative pitch P1, the computer can automatically set the arrangement of all holes 2 at multiple pitches P.

[0047] As shown in Figure 6, in the design method of this embodiment, a third step S3 is performed in which the arrangement of holes 2 for a tire T different from the tire T in which the holes 2 were set in the second step S2 is set. With this design method, by setting the arrangement of holes 2 for a representative pitch P1 of a representative size, the arrangement of holes 2 for all pitches P of all tire sizes can be set.

[0048] Figure 8 is a flowchart of the third step S3. As shown in Figure 8, the third step S3 of this embodiment is an input step S31 in which pattern data for tread patterns of all tire sizes is acquired. It is desirable that the pattern data be automatically acquired by the computer by inputting the design data of the tire T.

[0049] In this embodiment, the third step S3, following the input step S31, is a full development step S32 in which a development rule is applied to all of the multiple pitches P of the vulcanization mold 1 corresponding to all tire sizes to set the arrangement of the holes 2. Such a third step S3 can suppress setting errors and allows for the accurate setting of the arrangement of the vent holes 2 for all tire sizes in a short time.

[0050] The arrangement of holes 2 with multiple pitches P for all tire sizes may be set, for example, by applying an expansion rule to the arrangement of holes 2 with a representative pitch P1 for a representative size, or it may be set based on the arrangement of holes 2 with approximately the same size pitch P that has already been set. It is desirable that the pitch P to which the expansion rule is applied is selected to be one that can be set accurately in a short amount of time.

[0051] Figure 9 is a partial unfolded view showing the arrangement of holes 2 with multiple pitches P of a representative size, and Figure 10 is a partial unfolded view showing the arrangement of holes 2 with multiple pitches P of a second size. Figure 9 illustrates the representative pitch P1 and second pitch P2 of the representative size. Figure 10 illustrates the representative pitch P3 and second pitch P4 of the second size. The width W2 of the area 4 of the second size is exemplified to be larger than the width W1 of the area 4 of the representative size.

[0052] As shown in Figures 9 and 10, the arrangement of holes 2 with a representative pitch P3 of the second size is preferably set based on the representative pitch P1 of the representative size. The arrangement of holes 2 with a representative pitch P3 of the second size may also be set based on, for example, the second pitch P2 of the representative size.

[0053] Similarly, the arrangement of the holes 2 with a representative pitch P3 of the second size may be set based on, for example, the representative pitch P1 of the representative size, the second pitch P2 of the representative size, or the representative pitch P3 of the second size.

[0054] Figure 10 illustrates a second pitch P4 in which, in addition to the first hole 2a, second hole 2b, third hole 2c, and fourth hole 2d, fifth hole 2e and sixth hole 2f are additionally arranged as holes 2. Thus, the development rule of this embodiment has a setting condition to add holes 2 when the arrangement parameter of holes 2 exceeds a predetermined value. Similarly, the development rule may have a setting condition to delete holes 2 when, for example, the arrangement parameter of holes 2 falls below a predetermined value.

[0055] It is desirable that the arrangement of the holes 2, which are to be increased or decreased, be predetermined based on the tread pattern of the tire T. In other words, the deployment rule of this embodiment allows for an increase or decrease in the number of holes 2, which are predetermined based on the tread pattern of the tire T. Such a deployment rule can suppress poor air discharge during vulcanization molding and allows for accurate setting of the arrangement of holes 2 in a short amount of time.

[0056] Although particularly preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above and can be implemented in various modified forms.

[0057] [Note] The present invention is as follows:

[0058] [Invention 1] A design method for arranging vent holes in a mold for vulcanizing tires, The vulcanization molding die includes a plurality of pattern components with pitches corresponding to the tread pattern of the tire, In the vulcanizing mold, by setting the arrangement of the holes for a representative pitch which is one of the plurality of pitches, the arrangement of all the holes for the plurality of pitches is set. Design method.

[0059] [Invention 2] A first step is to set development rules for arranging the aforementioned holes, The second step includes setting the arrangement of the holes, The second step is, An input process for acquiring the pattern data of the aforementioned tread pattern, Area setting step: Setting an area for identifying the pattern components of the representative pitch, A process for identifying the pattern components in the area of ​​the representative pitch, A hole setting step of setting the arrangement of the holes in the area, A step of acquiring parameters related to the development rule for the arrangement of the holes in the area, The design method according to the present invention 1, comprising a development step of applying the development rule to a plurality of pitches other than the representative pitch to set the arrangement of the holes.

[0060] [Invention 3] The third step includes setting the arrangement of the holes, which are of a different tire size than the aforementioned tire, The third step is, The entire input process involves acquiring the pattern data for the tread patterns of all the aforementioned tire sizes, The design method according to the present invention, comprising a full unfolding step of applying the unfolding rule to all of the plurality of pitches of the vulcanizing mold corresponding to all of the aforementioned tire sizes to set the arrangement of the holes.

[0061] [4th Invention] The design method according to invention 2 or 3, wherein the development rule is a setting condition for parametrically developing the parameters of the arrangement of the holes in the area.

[0062] [5th ​​Invention] The design method according to any one of inventions 2 to 4, wherein the deployment rule allows for an increase or decrease in the number of pre-set holes based on the tread pattern.

[0063] [Invention 6] The design method according to any one of inventions 2 to 5, wherein the number of holes arranged in the area is 1 to 200.

[0064] [7th Invention] The design method according to any one of inventions 1 to 6, wherein the hole corresponds to at least one of a vent hole, a vent piece, and a spring vent.

[0065] [8th Invention] The design method according to any one of invention 1 to 7, wherein the inner diameter of the hole is 0.1 to 5.0 mm.

[0066] [Invention 9] The design method according to any one of inventions 1 to 8, wherein the pattern component corresponds to at least one of the lateral grooves and sipes of the tire. [Explanation of Symbols]

[0067] 1. Vulcanizing mold 2 holes 3 Pattern Components

Claims

1. A design method for arranging vent holes in a mold for vulcanizing tires, The vulcanization molding die includes a plurality of pattern components with pitches corresponding to the tread pattern of the tire, In the vulcanizing mold, by setting the arrangement of the holes for a representative pitch which is one of the plurality of pitches, the arrangement of all the holes for the plurality of pitches is set. Design method.

2. A first step is to set development rules for arranging the aforementioned holes, The second step includes setting the arrangement of the holes, The second step is, An input process for acquiring the pattern data of the aforementioned tread pattern, Area setting step: Setting an area for identifying the pattern components of the representative pitch, A process for identifying the pattern components in the area of ​​the representative pitch, A hole setting step of setting the arrangement of the holes in the area, A step of acquiring parameters related to the development rule for the arrangement of the holes in the area, The design method according to claim 1, comprising a development step of applying the development rule to a plurality of pitches other than the representative pitch to set the arrangement of the holes.

3. The third step includes setting the arrangement of the holes for a tire of a different size than the aforementioned tire, The third step is, The entire input process involves acquiring the pattern data for the tread patterns of all the aforementioned tire sizes, The design method according to claim 2, comprising a full unfolding step of applying the unfolding rule to all of the plurality of pitches of the vulcanizing mold corresponding to all of the tire sizes to set the arrangement of the holes.

4. The design method according to claim 3, wherein the development rule is a setting condition for parametrically developing the parameters of the arrangement of the holes in the area.

5. The design method according to claim 4, wherein the deployment rule allows for an increase or decrease in the number of pre-set holes based on the tread pattern.

6. The design method according to any one of claims 2 to 5, wherein the number of holes arranged in the area is 1 to 200.

7. The design method according to any one of claims 1 to 5, wherein the hole corresponds to at least one of a vent hole, a vent piece, and a spring vent.

8. The design method according to any one of claims 1 to 5, wherein the inner diameter of the hole is 0.1 to 5.0 mm.

9. The design method according to any one of claims 1 to 5, wherein the pattern component corresponds to at least one of the lateral grooves and sipes of the tire.

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