WO2019102649A1

WO2019102649A1 - Method for manufacturing tire mold

Info

Publication number: WO2019102649A1
Application number: PCT/JP2018/027958
Authority: WO
Inventors: 石原　泰之
Original assignee: 株式会社ブリヂストン
Priority date: 2017-11-27
Filing date: 2018-07-25
Publication date: 2019-05-31
Also published as: JP2019093672A; CN111465478A

Abstract

The purpose of the present invention is to enable easy manufacturing of a divided mold of a tire mold to improve the efficiency of manufacturing the tire mold. Provided is a method for manufacturing a tire mold having a plurality of divided molds arranged in a ring shape along a tire circumferential direction. The method for manufacturing the tire mold comprises: a step of forming a plurality of protrusion parts (16) coupled together by a coupling part (17); a step of manufacturing a mold body cast (20); a step of attaching the plurality of protrusion parts (16) to the mold body cast (20); and a step of removing the coupling part (17) from the plurality of protrusion parts (16) to manufacture a divided mold having the mold body cast (20) and the plurality of protrusion parts (16).

Description

Method of manufacturing mold for tire

The present invention relates to a method for manufacturing a tire mold having a plurality of divided molds arranged in a ring along the tire circumferential direction.

In the split mold of the tire mold, the shape of the molding portion for molding the tire is complicated, and the molding portion is formed into a shape which is difficult to form by machining corresponding to the shape of the tread portion of the tire. Therefore, a casting method is widely adopted for the production of the split mold. In addition, conventionally, there is known a method for manufacturing a tire molding mold in which a set of sectional molds (divided molds) is manufactured from a single ring-shaped casting (see Patent Document 1).

The manufacturing efficiency is enhanced by manufacturing one set of divided molds for a tire mold from one casting. Moreover, in all the division molds, casting conditions become the same and casting results (shrinkage amount etc.) become uniform. However, as the tire molded by the tire mold becomes larger, the weight of the casting increases and casting becomes difficult. In addition, due to the increase in casting time and solidification time, high technology is required to prevent casting defects. Depending on the weight of the casting, the weight of the melt may exceed the pourable weight.

Therefore, in general, when manufacturing a tire mold smaller than a truck-bus tire (or a comparable tire), a set of divided molds is manufactured from one casting. When manufacturing a tire mold of a size larger than that of a truck / bus tire, castings (raw materials) of split molds are separately cast to produce one split mold from one raw material. In particular, in the case of molds for large tires, it is difficult to directly form the molding portion of the split mold (material) by precision casting from the viewpoint of dimensional accuracy, and the molding portion of the material is processed by machining.

FIGS. 20 to 25 are diagrams showing a manufacturing procedure of the conventional tire mold 100, and schematically show the material 120 or the split mold 110 of the split mold 110 at each stage. In FIG. 20 to FIG. 24, the shape of the split mold 110 and the like are indicated by a dashed line on the material 120. FIGS. 20 to 23 show the processing procedure of one split mold 110 (material 120), and FIGS. 24 and 25 show the processing procedure of a plurality of split molds 110. FIG. Also, FIGS. 20B to 23B show the material 120 as viewed in the direction of arrow V1 in FIGS. 20A to 23A, respectively. 24A and 25A are plan views of the plurality of materials 120 or the plurality of divided molds 110, and FIGS. 24B and 25B are cross-sectional views taken along line V2-V2 of FIGS. 24A and 25A, respectively.

As shown, the block-shaped material 120 is formed by casting (see FIG. 20). At the same time, a solidified portion (pouring portion 121) of the solidified feeder is formed integrally with the material 120. Subsequently, the feeder portion 121 is cut from the material 120 (see FIG. 21). The one end (first end 122) of the material 120 is machined to form the reference surface 111 of the split mold 110 on the material 120 (see FIG. 22). Further, the two side portions 123 of the material 120 are processed to form the two divided surfaces 112 of the split mold 110 on the material 120 (see FIG. 23).

Next (see FIG. 24), the plurality of materials 120 are combined in a ring shape in a state where the divided surfaces 112 are in contact with each other. In this state, the other end (second end 124) of the plurality of raw materials 120 is processed by machining (see FIG. 25) to form the end face 113 of the split mold 110 on the raw material 120. Further, the inner circumferential portion 125 and the outer circumferential portion 126 of the plurality of materials 120 are processed to form the molding portion 114 and the back surface portion 115 of the split mold 110 as the material 120. Further, the molding portion 114 is provided with a projection 116 for molding a recess in the tread portion of the tire.

When it is not possible to manufacture one set of split molds 110 of the tire mold 100 from one ring-shaped casting, the material 120 of the split molds 110 is cast separately and one split mold 110 is machined by one material 120 Although it manufactures, processing of the raw material 120 of the split mold 110 takes time and effort. In particular, since the forming portion 114 is provided with the protruding portion 116, the shape becomes complicated, and it takes a lot of labor and time to process. Therefore, it is difficult to improve the manufacturing efficiency of the split mold 110, and the work period for manufacturing the tire mold 100 becomes long. On the other hand, if the material 120 is formed in a shape close to the completed shape of the split mold 110, machining of the material 120 is simplified. However, in this case, it takes time and effort to process a mold for casting the material 120. From the above, it is required to improve the manufacturing efficiency of the tire mold 100 so that the tire mold 100 can be manufactured in a shorter construction period.

Unexamined-Japanese-Patent No. 2004-358849

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to improve manufacturing efficiency of a mold for a tire by enabling easy manufacture of a divided mold for a mold for a tire.

The present invention is a method for manufacturing a tire mold having a plurality of divided molds arranged in a ring along the tire circumferential direction. The method for manufacturing a mold for a tire comprises the steps of: forming a plurality of projections connected by a connecting portion; manufacturing the mold body mold; assembling the plurality of projections on the mold body mold; and forming the plurality of projections And removing the connecting portion from the mold to produce a split mold having a mold main body type and a plurality of protrusions.

ADVANTAGE OF THE INVENTION According to this invention, the division mold of the mold for tires can be manufactured simply, and the manufacturing efficiency of the mold for tires can be improved.

It is a figure which shows the mold for tires of 1st Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 1st Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 1st Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 1st Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 1st Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 1st Embodiment. It is a perspective view when the mold for tires is completed. It is a perspective view which shows the manufacturing procedure of the mold for tires of 2nd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 2nd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 2nd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 2nd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 2nd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 2nd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 3rd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 3rd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 3rd Embodiment. It is a figure which shows the hole and groove | channel of a projection part. It is a perspective view which shows the manufacturing procedure of the mold for tires of 3rd Embodiment. It is a perspective view which shows the manufacturing procedure of the mold for tires of 3rd Embodiment. It is a figure which shows the manufacturing procedure of the conventional mold for tires. It is a figure which shows the manufacturing procedure of the conventional mold for tires. It is a figure which shows the manufacturing procedure of the conventional mold for tires. It is a figure which shows the manufacturing procedure of the conventional mold for tires. It is a figure which shows the manufacturing procedure of the conventional mold for tires. It is a figure which shows the manufacturing procedure of the conventional mold for tires.

One embodiment of a method for manufacturing a tire mold of the present invention will be described with reference to the drawings.
In the method for manufacturing a mold for a tire of the present embodiment, a mold for a tire and a divided mold for a mold for a tire are manufactured. The tire mold is a molding for a tire, and is used at the time of molding of the tire (during vulcanization). A tire is vulcanized while being molded by a tire mold.

First Embodiment
FIG. 1 is a view showing the tire mold 1 of the first embodiment. FIG. 1A is a plan view of the tire mold 1 viewed from the outer side in the width direction of the tire, and FIG. 1B is a cross-sectional view of the tire mold 1 cut along line X1-X1 of FIG. 1A.
As illustrated, the tire mold 1 is a ring-shaped outer mold for molding the outer surface of the tire, and is provided in a tire molding apparatus (vulcanization apparatus). The tire mold 1 forms a tread portion of a tire around a ring-shaped tire.

With respect to the direction of the tire mold 1, the width direction (mold width direction W1) of the tire mold 1 coincides with the tire width direction (tire width direction). The radial direction (mold radial direction K1) of the tire mold 1 coincides with the radial direction of the tire (tire radial direction), and the circumferential direction (mold circumferential direction S1) of the tire mold 1 corresponds to the circumferential direction of the tire (mold circumferential direction S1). Match the tire circumferential direction).

The tire mold 1 has a plurality of (here, 18) divided molds 10 arranged in a ring along the mold circumferential direction S1 (tire circumferential direction), and the tire is formed by the plurality of divided molds 10 . The plurality of divided molds 10 are segments divided in the mold circumferential direction S1, and are tread molds for molding the tread portion of the tire. The plurality of divided molds 10 move in a mold radial direction K1 (tire radial direction) in the tire molding apparatus. The tire mold 1 includes a reference surface 11 as a processing reference, an end surface 12 opposite to the reference surface 11, a molding portion 13 formed on the tire side, and a rear surface side in each of the divided molds 10. It has a formed back portion 14 and two divided surfaces 15.

The reference surface 11 is one end surface in the mold width direction W1 (tire width direction) of the split mold 10. The end face 12 is the other end face in the mold width direction W1 of the split mold 10. The molding portion 13 is an inner peripheral portion of the tire mold 1 and is located inside the mold radial direction K1. The back surface portion 14 is an outer peripheral portion of the tire mold 1 and is an inclined surface located on the opposite side of the molding portion 13 (outside of the mold radial direction K1). The dividing surfaces 15 are side surfaces positioned on both sides of the mold circumferential direction S <b> 1 of the dividing mold 10.

At the time of molding of the tire, the plurality of divided molds 10 of the tire mold 1 are arranged in order along the mold circumferential direction S1 with the divided surfaces 15 in contact with each other. Thereby, a plurality of divided molds 10 are combined in a ring shape to surround the tire. In that state, the tire mold 1 and the molding portion 13 are disposed along the mold width direction W1. The tire mold 1 contacts the tire (tread portion) at the molding portion 13 of the split mold 10 and shapes the tire by the molding portion 13. The molding portion 13 is provided with a protrusion 16. The forming portion 13 forms a recess (for example, a groove, a sipe) in the tread portion of the tire by the projection 16.

Next, a method of manufacturing the tire mold 1 of the first embodiment will be described.
2 to 6 are perspective views showing the manufacturing procedure of the tire mold 1 of the first embodiment. 2 to 6 show one of the divided molds 10 of the tire mold 1. FIG. 7 is a perspective view when the tire mold 1 is completed, and also a perspective view when the tire mold 1 in the second embodiment described later is completed.

When manufacturing the mold 1 for tires, the several projection part 16 connected by the connection part 17 is formed. Further, the mold body mold 20 is manufactured, and the plurality of protrusions 16 are assembled to the mold body mold 20. The connecting portion 17 is removed from the plurality of protrusions 16 to manufacture a split mold 10 having the mold main body 20 and the plurality of protrusions 16. Hereinafter, each process of the manufacturing method of these mold 1 for tires is demonstrated in detail.

At the process of forming the several projection part 16 connected by the connection part 17, the plate-shaped projection raw material 30 is prepared. One protrusion material 30 corresponds to one part of the split mold 10, and is, for example, a forging made of steel. Here, although the projection material 30 to be prepared is 18 in one set of the tire mold 1 here, it is not limited to this. As shown in FIG. 2, the outer surface (inner circumferential surface, outer circumferential surface, upper surface, lower surface, etc.) of the prepared protrusion material 30 is machined (turned, milled, etc.) to adjust the surface shape of the protrusion material 30.

Subsequently, as shown in FIG. 3, the projection material 30 with the surface shape adjusted is subjected to a shape removal process, and an unnecessary portion is removed from the projection material 30. The shape removal processing is, for example, mechanical processing such as milling, wire electric discharge processing, melting cutting (gas melting, arc cutting), plasma cutting, abrasive water jet (high pressure water cutting) and the like. By the shape removal process, the projection material 30 is left except for the plurality of protrusions 16, the connection portion 17, the one end joint portion (here, the upper end joint portion 18), and the other end joint portion (here, the lower end joint portion 19). Cut out the unnecessary part from. Thus, the connecting portion 17 and the plurality of protruding portions 16 are formed on the protruding material 30.

The connecting portion 17 is a member for connecting the protruding portions 16 separated from each other, and also serves as a reinforcing portion for reinforcing a connecting body having the connecting portion 17 and the plurality of protruding portions 16. All protrusions 16 of one split mold 10 are connected by the connecting portion 17. The upper end joint portion 18 and the lower end joint portion 19 are members for holding the plurality of protrusions 16 and the connecting portion 17, and are connected to the upper and lower end portions of the plurality of protrusions 16 and the connecting portion 17. A machining allowance is attached to the plurality of protrusions 16 and the connecting portion 17, and the plurality of protrusions 16 and the connecting portion 17 are formed to be larger than the respective final shapes.

It is preferable to use melting (especially gas melting), plasma cutting, or abrasive water jet in shape removal processing of the projection material 30. That is, in the case of melting, plasma cutting, and abrasive water jet, the separation speed of unnecessary portions is extremely high. Therefore, the number of processing steps for shape removal processing can be reduced to 50% or less, as compared with other processing.

After cutting unnecessary portions of the projection material 30 (removing the shape), as shown in FIG. 4, machining such as NC milling is performed on the plurality of projections 16 and the connection portion 17, and the plurality of projections 16 and the connection portion 17 Adjust the shape of At this time, the connecting portion 17 is processed into a shape recessed from the protrusion 16. As a result, when the plurality of protrusions 16 are assembled to the mold body mold 20, a gap is formed between the connecting portion 17 and the mold body mold 20. The upper end joint portion 18 and the lower end joint portion 19 are grip portions and can be gripped by a processing machine at the time of machining.
As described above, by subjecting the plate-like protrusion material 30 to various kinds of machining, the plurality of protrusion portions 16 connected by the connection portion 17 are formed. At this time, the upper end joint portion 18 and the lower end joint portion 19 are connected to the upper and lower end portions of the plurality of protrusions 16 and the connecting portion 17.

Next, in the process of manufacturing the mold body mold 20, as shown in FIG. 5, a block-shaped mold body mold material 31 is prepared. One mold body mold material 31 corresponds to one part of the split mold 10, and is formed, for example, by forging or casting. Although the mold main body type material 31 to be prepared is 18 in one set of the tire mold 1 here, it is not limited to this. Various machining is performed on the prepared mold main body mold material 31. As a result, the reference surface 11, the end surface 12, the molding portion 13, the back surface portion 14, and the two divided surfaces 15 are formed on the mold body mold material 31 (mold body mold 20).
As described above, the mold main body mold 20 is manufactured by performing various kinds of machining on the block-shaped mold main body mold material 31.

Next, in the step of assembling the plurality of protrusions 16 to the mold body mold 20, the plurality of formed protrusions 16 are assembled to the manufactured mold body mold 20. That is, as shown in FIG. 5, while fixing the mold main body mold 20 and grasping the upper end joint portion 18 and the lower end joint portion 19, the plurality of protrusions 16 are assembled to the molding portion 13 of the mold main body mold 20. At the time of assembly of the plurality of protrusions 16 to the mold main body mold 20, for example, the plurality of protrusions 16 and the molding portion 13 of the mold main body mold 20 are joined by welding around the protrusions 16. On the other hand, when assembling the plurality of protrusions 16 into the mold main body 20, for example, a fixing member such as a screw may be used, or welding and a screw may be used in combination.

Next, the connecting portion 17 is removed from the plurality of protrusions 16 to manufacture the split mold 10 having the mold main body 20 and the plurality of protrusions 16. At that time, as shown in FIG. 6, all the connecting portions 17 and the two

joint portions

18 and 19 are removed by machining such as milling. When the connecting portion 17 is removed, a gap is formed between the connecting portion 17 and the molding portion 13 of the mold main body 20. Therefore, the connecting portion 17 can be easily removed without damaging the molding portion 13 of the mold main body mold 20. After removing the connecting portion 17, the plurality of protrusions 16 are subjected to mechanical processing such as milling to finish the plurality of protrusions 16.
As described above, by removing the connecting portions 17 and the like from the plurality of protrusions 16, one split mold 10 having the mold main body 20 and the plurality of protrusions 16 is manufactured.

Through the above steps, one set (18 pieces) of split molds 10 for the tire mold 1 is manufactured, and the 18 split molds 10 are arranged in a ring and combined. Thus, one tire mold 1 shown in FIG. 7 is manufactured.

As described above, the projection material 30 is machined separately from the fabrication of the mold main body mold 20 to form the plurality of projections 16 connected by the connecting part 17. Therefore, the plurality of protrusions 16 can be easily manufactured, and the mold main body mold 20 can also be easily manufactured. In addition, even if the plurality of protrusions 16 and the mold main body 20 have a shape that is difficult to form, the respective processing can be easily performed. Therefore, the manufacturing efficiency of the split mold 10 and the mold 1 for a tire can be improved, and thereby, the mold 1 for a tire can be manufactured in a short construction period.

Moreover, the division mold 10 is manufactured by combining the several protrusion part 16 and the mold main body type | mold 20 which were manufactured at separate processes. Along with this, standardization of the plurality of protrusions 16 and the mold main body mold 20 is facilitated. The standardization of the plurality of protrusions 16 and the mold main body type 20 makes it possible to improve the efficiency of the work and shorten the manufacturing period of the tire mold 1. The processing accuracy of the plurality of protrusions 16 and the mold main body mold 20 can also be improved.

Next, another embodiment will be described. With regard to the following embodiments, the description of the same matters as the first embodiment is omitted, and the matters different from the first embodiment will be described.
Second Embodiment
The manufacturing method of the mold 1 for tires of 2nd Embodiment is demonstrated.
8 to 13 are perspective views showing a manufacturing procedure of the tire mold 1 of the second embodiment.

In the step of forming the plurality of protrusions 16 connected by the connecting portion 17, the protrusion material 30 is prepared. The protrusion material 30 is ring-shaped (annular), and is formed by casting, for example. A plurality of projections 16 provided on the plurality of divided molds 10 are formed from the one ring-shaped projection material 30. Here, the plurality of projections 16 of the nine divided molds 10 are formed on one projection material 30. The tire mold 1 has 18 divided molds 10. Therefore, in order to manufacture one tire mold 1, two ring-shaped projection materials 30 are prepared. However, the number of the plurality of protrusions 16 formed from one ring-shaped protrusion material 30 and the number of the protrusion materials 30 to be prepared are not limited to this. As shown in FIG. 8, the outer surface (inner circumferential surface, outer circumferential surface, upper surface, lower surface, etc.) of the prepared ring-shaped protrusion material 30 is machined (turned, milled, etc.) to adjust the surface shape of the protrusion material 30. .

Subsequently, as shown in FIG. 9, the ring-shaped projection material 30 whose surface shape is adjusted is subjected to shape extraction processing so that unnecessary portions are removed from the projection material 30. Unnecessary portions are cut out from the projection material 30, leaving the plurality of protrusions 16, the connection portion 17, the upper end joint portion 18, the lower end joint portion 19, and the ring joint portion 21 by shape removal processing. The ring joint portion 21 is a portion connecting the plurality of projections 16 and the connecting portion 17 of each of the divided molds 10, and here, connects the plurality of projections 16 and the connecting portion 17 of the nine divided molds 10.

After cutting unnecessary portions of the ring-shaped projection material 30 (removing the shape), as shown in FIG. 10, the plurality of projections 16 and the connecting portion 17 are machined by NC milling or the like, and the plurality of projections 16 and Adjust the shape of the connecting portion 17. At this time, the connecting portion 17 is processed into a shape recessed from the protrusion 16.
Subsequently, as shown in FIG. 11, the ring-shaped projection material 30 from which unnecessary portions are cut is subjected to machining such as milling, wire electric discharge machining, fusion cutting, plasma cutting, abrasive water jet and the like. Thereby, the ring joint portion 21 is cut out from the projection material 30.
As described above, by subjecting one ring-shaped protrusion material 30 to various kinds of machining, the plurality of protrusions 16 and the connecting portions 17 of nine divided molds 10 are formed at one time. At this time, the upper end joint portion 18 and the lower end joint portion 19 are connected to the upper and lower end portions of the plurality of protrusions 16 and the connecting portion 17.

Next, in the process of manufacturing the mold main body mold 20, as in the first embodiment, the block main body mold material 31 is subjected to various kinds of machining to manufacture the mold main body mold 20.

Next, in the step of assembling the plurality of projections 16 into the mold body mold 20, as shown in FIG. 12, the plurality of projections 16 are joined to the molding portion 13 of the mold body mold 20 as in the first embodiment. Assemble by.

Next, the connecting portion 17 is removed from the plurality of protrusions 16 to manufacture the split mold 10 having the mold main body 20 and the plurality of protrusions 16. At that time, as shown in FIG. 13, all the connecting portions 17 and the two

joint portions

18 and 19 are removed by machining such as milling as in the first embodiment. Thereafter, the plurality of protrusions 16 are machined to finish the plurality of protrusions 16. As a result, the connecting portions 17 and the like are removed from the plurality of protrusions 16 to manufacture one split mold 10 having the mold main body 20 and the plurality of protrusions 16.

As described above, since the projection material 30 is a ring-shaped member, it is possible to form a plurality of projections 16 provided on the plurality of divided molds 10 at one time from one ring-shaped projection material 30. Therefore, the number of processing steps can be significantly reduced, and the efficiency of forming the plurality of protrusions 16 can be further improved. In addition, by forming the plurality of protrusions 16 simultaneously from one ring-shaped protrusion material 30, it is possible to suppress variations among the plurality of protrusions 16.

Third Embodiment
Next, a method of manufacturing the tire mold 1 of the third embodiment will be described.
Here, unlike the first and second embodiments, assembly of the projection 16 to the mold main body mold 20 is performed by brazing, and the projection 16 and the mold main body mold 20 are joined by brazing.
14 to 16, 18, and 19 are perspective views showing a part of the manufacturing procedure of the tire mold 1 of the third embodiment. FIG. 17 is a view showing the holes 33 and the grooves 34 of the protrusion 16. 17A shows the holes 33 and the grooves 34 viewed from the direction of arrow Y1 in FIG. 16, and FIG. 17B shows the holes 33 and the grooves 34 viewed from the direction of arrow Y2 in FIG.

At the process of forming the several projection part 16 connected by the connection part 17, the plate-shaped projection raw material 30 is prepared similarly to 1st Embodiment. Further, as shown in FIG. 14, machining (turning, milling, etc.) is performed on the outer surface (inner peripheral surface, outer peripheral surface, upper surface, lower surface, etc.) of the prepared protrusion material 30 to adjust the surface shape of the protrusion material 30.
Subsequently, as shown in FIG. 15, the projection material 30 with the surface shape adjusted is subjected to shape removal processing, and the unnecessary portions are removed from the projection material 30. Unnecessary portions are cut out from the projection material 30 by leaving the plurality of protrusions 16, the connection portion 17, the upper end joint portion 18, and the lower end joint portion 19 by shape removal processing.

After cutting unnecessary portions of the projection material 30 (removing the shape), as shown in FIG. 16, machining such as NC milling is performed on the plurality of projections 16 and the connecting portion 17, and the plurality of projections 16 and the connecting portion 17 Adjust the shape of In addition, a plurality of holes 33 are provided in each protrusion 16. Each hole 33 penetrates the protrusion 16. In addition to the holes 33, as shown in FIG. 17, a groove 34 is provided on the surface of the protrusion 16 on the side to be bonded to the molding portion 13 of the mold main body 20. The plurality of holes 33 open at the bottom of the groove 34, and the groove 34 leads to the plurality of holes 33.
As described above, by subjecting the protrusion material 30 to various kinds of machining, the plurality of protrusion portions 16 connected by the connection portion 17 are formed.

Next, in the process of manufacturing the mold main body mold 20, the mold main body mold 20 is manufactured by performing various kinds of machining on the block-shaped mold main body mold material 31 as in the first or second embodiment.

Next, in the step of assembling the plurality of protrusions 16 into the mold main body mold 20, as shown in FIG. 18, the mold main body die 20 is disposed laterally below the plurality of protrusions 16. Subsequently, a plurality of laterally oriented protrusions 16 are disposed on the mold main body mold 20 and assembled to the molding portion 13 of the mold main body mold 20. The plurality of holes 33 are disposed along the vertical direction above the mold body mold 20. In this state, the projection 16 and the mold main body mold 20 are joined by brazing, and the projection 16 is assembled to the mold main body mold 20. Specifically, a brazing material is put in advance in the plurality of holes 33 provided in the projection 16, and the mold main body mold 20 and the plurality of projections 16 are put into the heating furnace. In the heating furnace, the mold body mold 20 and the plurality of projections 16 are heated to melt the brazing material in the plurality of holes 33.

The brazing material melts from the holes 33 toward the grooves 34 and spreads throughout the grooves 34. Further, the brazing material enters between the projection 16 and the molding portion 13 of the mold main body mold 20, and joins the projection 16 and the molding portion 13 of the mold main body mold 20. As a result, the plurality of protrusions 16 are assembled to the molding portion 13 of the mold main body mold 20. Subsequently, the closing member is driven into a plurality of holes 33 provided in each of the protrusions 16 to close the holes 33. Thereafter, the surface of the hole 33 is finished.

Next, the connecting portion 17 is removed from the plurality of protrusions 16 to manufacture the split mold 10 having the mold main body 20 and the plurality of protrusions 16. At that time, as shown in FIG. 19, all the connecting portions 17 and the two

joint portions

18 and 19 are removed by machining such as milling as in the first and second embodiments. Thereafter, the plurality of protrusions 16 are machined to finish the plurality of protrusions 16. As a result, the connecting portions 17 and the like are removed from the plurality of protrusions 16 to manufacture one split mold 10 having the mold main body 20 and the plurality of protrusions 16.

As described above, when assembling the plurality of protrusions 16 into the mold main body 20, the protrusions 16 and the mold main body 20 are joined by brazing, whereby the protrusions 16 and the molded portion 13 of the mold main body 20 are assembled. Can be joined in a more gap-free state. As a result, the projection 16 can be firmly attached to the mold body 20. In addition, since the bonding is performed by brazing, the projection 16 and the mold main body mold 20 can be easily connected, and the number of assembling operations can be significantly reduced. By supplying the brazing material from the hole 33 to the groove 34, the shortage of the brazing material can be prevented, and the projection 16 and the mold main body mold 20 can be reliably joined. Since a gap is formed between the connecting portion 17 and the molding portion 13 of the mold main body mold 20, it is possible to prevent the connecting portion 17 from being bonded to the mold main body mold 20 by the brazing material.

In addition, although assembly | attachment of the projection part 16 to the mold main body type | mold 20 arrange | positions the mold main body type | mold 20 below, joins and assembles the projection part 16 from upper direction, it is not limited to this. For example, the positions of the mold body mold 20 and the plurality of protrusions 16 may be reversed, the mold body mold 20 may be disposed on the upper side, and the plurality of protrusions 16 may be joined and assembled from below. However, in the case where the plurality of protrusions 16 are joined from below and assembled, the workability is deteriorated and the plurality of protrusions 16 may be damaged.

The bonding of the plurality of protrusions 16 and the mold main body 20 by brazing is not limited to the above embodiment. For example, the hole 33 for containing the brazing material may be provided in the mold main body mold 20 instead of the protrusion 16. In this case, the holes 33 pass through the mold body mold 20 and the brazing material is put into the holes 33 of the mold body mold 20.
Further, the plurality of projections 16 or the holes 33 provided in the mold main body mold 20 may not penetrate through the projections 16 or the mold main body mold 20. In this case, an amount of brazing material necessary for brazing is put in the holes 33 in advance before the projection 16 is assembled to the mold body mold 20. Since the holes 33 provided in the projection 16 or the mold main body mold 20 are not penetrated, the holes 33 can be closed after assembly, and the surface can not be subjected to finish processing.

(Production test of tire mold 1)
In order to confirm the effects of the present invention, a manufacturing test of the tire mold 1 was performed.
First, the dimensions (see FIG. 1) of the tire mold 1 will be described. The inner diameter N (diameter) is about 3500 mm, the height H of the split mold 10 is about 750 mm, the width B of the reference surface 11 of the split mold 10 is about 450 mm, and the height P of the projection 16 provided on the molding portion 13 (projection size) Of the back surface 14 is about 17 °. The split mold 10 is a casting (carbon steel (SS 400) equivalent material), and was manufactured by casting.
In the manufacturing test of the mold 1 for a tire, the mold 1 for a tire was manufactured by the manufacturing method shown to the following comparative example 1 and Example 1, 2, 3, and each work period was compared. The work period to be compared is each work period of the production of the material, the formation of the projection, the formation of the outer portion, the assembling, and the finishing process. In addition, we also compared the overall construction period, which is the sum of these construction periods.

(Comparative example 1)
In Comparative Example 1, the mold for tire 100 was manufactured by the conventional manufacturing method (FIGS. 20 to 25). That is, the material of the split mold 110 was manufactured by near-net casting with a finishing cost of about 10 mm (production of material). The material was machined to process a plurality of projections 116 and an outer portion (formation of projections, formation of outer portion). Next, machining was performed on the molding portion 114 and the plurality of projections 116 to finish the molding portion 114 and the plurality of projections 116 (finish processing), and the split mold 110 was manufactured. The tire mold 100 is manufactured by arranging and combining the 18 divided molds 110 in a ring shape.

Example 1
In Example 1, the mold 1 for a tire was manufactured by the manufacturing method (FIGS. 8 to 13 and 7) of the second embodiment. That is, the ring-shaped projection material 30 and the mold main body type material 31 were manufactured by casting (production of material). The ring-shaped projection material 30 was machined by milling to form a plurality of projections 16 (formation of projections). Further, the mold main body material 31 was machined to produce a mold main body die 20 (formation of an outer portion). A plurality of protrusions 16 were joined and assembled to the mold body mold 20 (assembly). Next, machining was performed on the molding portion 13 and the plurality of projections 16 to finish the molding portion 13 and the plurality of projections 16 (finish processing), and the divided mold 10 was manufactured. The tire mold 1 is manufactured by arranging and combining the 18 divided molds 10 in a ring shape.

(Example 2)
The second embodiment is basically the same as the first embodiment, but differs in the following matters. That is, when forming the plurality of protrusions 16 (forming the protrusions), the machining applied to the ring-shaped protrusion material 30 was not performed by milling but was performed by plasma cutting. Thus, the mold for tire 1 is manufactured by manufacturing the mold part 10 and arranging and combining the 18 mold parts 10 in a ring shape.

(Example 3)
The third embodiment is basically the same as the second embodiment, but differs in the following matters. That is, when the projection 16 is joined and assembled to the mold main body mold 20 (assembly), the projection 16 and the mold main body mold 20 are joined by the brazing described in the third embodiment. As the brazing material, Cu-30% Zn-based brazing material was used. In brazing, the mold main body mold 20 and the plurality of protrusions 16 are heated to 850 ° C. and gradually cooled in an N ₂ displacement furnace. Thus, the mold for tire 1 is manufactured by manufacturing the mold part 10 and arranging and combining the 18 mold parts 10 in a ring shape.

(Test results)
The results of manufacturing tests of the tire mold 1 are shown in Table 1 below.
In addition, in Table 1, the whole construction period in the conventional manufacturing method which is the comparative example 1 is set to 1, and the index of each construction period was computed. Moreover, the numerical value in () is an index of each construction period at the time of setting production of the raw material of the comparative example 1 to one.

The overall construction term index of Examples 1, 2 and 3 is 0.79, 0.62, and 0.54, which is lower than the construction term index of Comparative Example 1. That is, in the manufacturing method shown in Examples 1, 2 and 3, the working period for manufacturing the tire mold 1 is shortened as compared with the conventional manufacturing method.

DESCRIPTION OF SYMBOLS 1 ... Mold for tires, 10 ... Division mold, 11 ... Reference surface, 12 ... End surface, 13 ... Molding part, 14 ... Back surface part, 15 ... Division surface, 16 ··· Protrusions, 17 · · · Connecting portions, 18 · · · Upper end joint portion, 19 · · · Lower end joint portion, 20 · · · Mold body type, 21 · · · Ring joint portion, 30 · · · · · · Material, 31: mold body material, 33: hole, 34: groove.

Claims

A manufacturing method of a tire mold having a plurality of divided molds arranged in a ring along a tire circumferential direction, the method comprising the steps of:
Forming a plurality of projections connected at the connection;
Manufacturing a mold body mold;
Assembling the plurality of protrusions into the mold body mold;
Removing the connecting portion from the plurality of protrusions to produce a split mold having the mold main body type and the plurality of protrusions;
A method of manufacturing a mold for a tire, comprising:
In the method of manufacturing a mold for a tire according to claim 1,
A method of manufacturing a mold for a tire, comprising the steps of: forming a plurality of protrusions, removing a unnecessary portion from a protrusion material, and forming a plurality of protrusions and a connecting portion.
In the method of manufacturing a mold for a tire according to claim 2,
A method of manufacturing a mold for a tire, wherein the projection material is ring-shaped.
In the method of manufacturing a mold for a tire according to any one of claims 1 to 3,
The tire mold is characterized in that the projection is assembled to the mold body mold by providing a hole in the projection or the mold body mold, inserting a brazing material into the hole, and bonding the projection and the mold body mold by brazing. Manufacturing method.
In the method of manufacturing a mold for a tire according to any one of claims 1 to 4,
What is claimed is: 1. A method of manufacturing a mold for a tire, comprising: forming a gap between the connecting portion and the mold body mold when the plurality of projections are assembled to the mold body mold.