JP2004058281A - Tire mold manufacturing method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire with a good RFV when the tire is manufactured using a tire mold by manufacturing the tire mold having an enhanced RRO or the like on a tread molding face. <P>SOLUTION: When the tire mold 100 to be used during vulcanizing the tire is manufactured, segments 103 corresponding to the plurally divided shape of the tire mold 100 in a peripheral direction are circumferentially arranged on a platen 2 so as to match the segments 103 with the tire mold 100. Further, the segments 103 are fixedly held by a container 3 arranged around the segments 103 and the tread forming faces 102 formed by connecting the faces 102 peripherally inside each of the segments 103, are continuously finish-worked in the peripheral direction. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for manufacturing a tire mold.
[0002]
[Prior art]
In the case of manufacturing a tire, in the process of vulcanizing a raw tire, a tire mold is used to adjust the raw tire to the outer shape of a product tire.
As shown in FIG. 6, the tire mold 100 has a donut shape, in which a disk-shaped molding space 101 (loading space for a raw tire) corresponding to the outer shape of a product tire is formed. In the molding space 101, a tread forming surface 102 for forming a tread surface of a tire is formed at a portion corresponding to a disk-shaped outer peripheral surface. 22809).
[0003]
Such a tire mold 100 is divided into a plurality (8 to 9) in the circumferential direction. Each of the divided parts is called a segment 103.
Conventionally, when such a tire mold 100 is manufactured, first, the individual segments 103 are separately manufactured, and then, the segments 103 are assembled in a circumferential arrangement on a predetermined installation table (not shown) for a vulcanization process. Was taking. That is, the tire mold 100 is formed by assembling the plurality of segments 103.
[0004]
Although illustration is omitted, the production of each segment 103 is performed by fixing a rough block-shaped material prepared by casting or shaving to a surface plate of a machine tool (milling machine or the like) and processing the material according to a design drawing. Is what you do. Therefore, in order to manufacture one tire mold 100, the fixing operation and the processing operation of the block-shaped material to the machine tool are repeated by the required number of segments 103.
[0005]
[Problems to be solved by the invention]
In the conventional method of manufacturing the tire mold 100, in the process of manufacturing the individual segments 103, even if it is performed carefully so as to obtain high accuracy in the work of fixing and processing the block-shaped material to the machine tool, there is only a slight However, if an error occurs, the error is accumulated when the tire mold 100 is assembled.
Therefore, such a cumulative error may cause an adverse effect on the RRO (roundness) of the tread forming surface 102 of the tire mold 100 as a whole.
[0006]
Needless to say, the RRO error appearing on the tread forming surface 102 leads to the RRO error on the tread surface of a tire manufactured using the tire mold 100, and as a result, the radial force variation (RFV: radial direction) of the tire (Fluctuation amount of force).
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a tire mold manufacturing method and a manufacturing apparatus capable of manufacturing a tire mold with an increased RRO or the like on a tread forming surface. .
[0007]
The ultimate object of the present invention is to make it possible to manufacture such a tire mold, thereby enabling the manufacture of a tire having good RFV.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has taken the following measures.
That is, in the method of manufacturing the tire mold 100 according to the present invention, the tire mold 100 is assembled by arranging the segments 103 having a plurality of shapes divided in the circumferential direction on the surface plate 2 in a circumferential arrangement.
The position of the segment 103 is fixed by holding the container 103 around the container 3.
[0009]
Next, the tread forming surface 102 formed over all the segments 103 in the tire mold 100 is processed and finished continuously in the circumferential direction.
In the tire mold 100 manufactured in this manner, the segments 103 are connected to each other in a predetermined circumferential arrangement to form an integrated state, and the tread forming surface 102 formed between these segments 103 is continuously formed. Since the work is finished, a work with continuity in the circumferential direction can be obtained as the work accuracy, and as a result, the RRO of the tread forming surface 102 can be increased.
[0010]
As a result, the tire manufactured using the tire mold 100 has a good RFV.
When processing the tread forming surface 102 of the tire mold 100 fixed on the surface plate 2, the tool 25 is held in a laterally projecting shape from the central space of the tire mold 100 toward the tread forming surface 102. The tread forming surface 102 may be machine-finished by the tool 25 while relatively rotating the surface plate 2 and the processing device 4.
[0011]
With this, the size and simplicity of the surface plate and the processing device can be reduced, and further, the processing accuracy can be easily increased, and the processing operation can be facilitated.
On the other hand, the apparatus for manufacturing a tire mold 100 according to the present invention has a platen 2 capable of supporting the tire mold 100 used at the time of vulcanizing a tire, and a circumferential arrangement on the platen 2 assuming the tire mold 100. A container 3 for holding a plurality of arranged segments 103, and a tread forming surface formed by being connected to the segments 103 fixed on the surface plate 2 corresponding to the tire mold 100 in the circumferential direction inside the segments 103. And a processing device 4 for continuously processing and finishing 102 in the circumferential direction.
[0012]
With such a configuration, the method for manufacturing the tire mold 100 according to the present invention can be easily performed.
In this case, the processing device 4 holds the tool 25 in a laterally projecting shape from the center space to the tread forming surface 102 with respect to the tire mold 100 fixed on the surface plate 2. Can be moved up and down in accordance with the width of the tread forming surface 102.
On the other hand, the surface plate 2 may be provided on the turntable 7 so as to be capable of turning.
[0013]
As a result, the structure is simplified and high-precision processing can be performed. In order to fix the container 3 to the surface plate 2, it is preferable to adopt the following structure.
As an example, a pressing plate 17 for positioning the segment 103 in the container 3 at a predetermined position by pressing the container 3 toward the surface plate 2 all around is prepared, and this pressing plate 17 is moved to the surface plate 2. There is a bolted structure.
This structure has the advantages that it is extremely simple in structure and can be implemented at low cost.
[0014]
Here, "predetermined positioning" means that when the tire mold 100 is fixed to the surface plate 2, the sidewall plate 10 is disposed at the center of the position. An outer peripheral position based on the reference (the segment 103 is arranged at this outer peripheral position) is assumed.
Therefore, by pressing the container 3 toward the surface plate 2 by the pressing plate 17, each segment 103 is accurately positioned around the side wall plate 10 as a reference.
[0015]
As another example, a pressing plate 17 for positioning the segment 103 in the container 3 at a predetermined position by pressing the container 3 toward the surface plate 2 over the entire circumference is prepared, and the pressing plate 17 is directed to the surface plate 2. And a pressing device 30 (for example, a hydraulic or pneumatic cylinder) that can be pressed by fluid pressure.
With this structure, there is an advantage that the pressing plate 17 can be quickly and easily changed to the pressed state or the released state.
"Predetermined positioning" is the same as above.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a first embodiment of a tire mold manufacturing apparatus 1 according to the present invention.
The tire mold manufacturing apparatus 1 includes a surface plate 2, a container 3, and a processing device 4.
The platen 2 is capable of supporting the tire mold 100 (see FIG. 6). Needless to say, this “tire mold” refers to an object to be processed.
[0017]
That is, the tire mold 100 is formed by assembling a plurality of (8 to 9) segments 103 in a circumferential arrangement. Inside the tire mold 100, a molding space 101 (space for loading a raw tire) corresponding to the outer shape of the product tire is formed, and a tread forming surface 102 is formed in the molding space 101.
The surface plate 2 is preferably set on a turntable 7 (see FIG. 4) and can be turned (see arrow P in FIG. 1).
[0018]
The container 3 holds and fixes the tire mold 100 on the surface plate 2. That is, the plurality of segments 103 forming the tire mold 100 are fixed while being circumferentially arranged.
An example of a specific structure of the container 3 is a combination of a pair of upper and lower sidewall plates 10, a sector 11, an actuator 12, a pair of upper and lower platens 13, and the like (see FIG. 4). A circumferential recess 14 for fitting the tire mold 100 is formed in the sector 11. In addition, the segments 103 are arranged on the upper and lower sidewall plates 10 at the outer peripheral positions thereof.
[0019]
In such a combination, the tapered surface 11a which spreads downward is formed on the outer peripheral surface of the sector 11, and the tapered surface 12a which is upwardly tapered is formed on the inner peripheral surface of the actuator 12 correspondingly. ing.
Then, by pressing the actuator 12 toward the sector 11 in a state where these tapers 11a and 12a are in contact with each other, the sector 11 is pushed in the diameter reducing direction, and is thereby fitted into the circumferential concave portion 14 of the sector 11. The tire mold 100 is tightened all around.
[0020]
The container 3 is assembled on the surface plate 2 in a state in which the tire mold 100 is incorporated in the circumferential concave portion 14 of the sector 11. Then, the holding plate 17 is put on the upper part of the container 3.
The holding plate 18 is formed in the shape of a donut plate that can press the container 3 (the upper platen 13) all around. The holding plate 17 is bolted to the surface plate 2 by bolts 18.
[0021]
Thus, all the segments 103 in the container 3 are accurately positioned around the sidewall plate 10 as a reference, and then fixed on the surface plate 2.
The processing device 4 continuously forms a tread forming surface 102 formed over all the segments 103 in a molding space 101 of the tire mold 100 fixed via the container 3 on the surface plate 2 in a circumferential direction. It is to be processed and finished.
The processing device 4 is provided in a state of being bent laterally so as to assume an L-shape at a tip end (lower end) thereof via an extension shaft 22 with respect to a spindle head 21 extending from the machine tool 20 and protruding therefrom. ing.
[0022]
As shown in FIGS. 2 and 3, the extension shaft 22 is provided at its upper end with a shank 23 that enables concentric fitting to the spindle head 21, and a pull stud 24 is protruded from a protruding end of the shank 23. Have been.
The machine tool 20 can move a portion provided with the spindle head 21 horizontally (fore and aft movement or left and right movement), and also can move this portion up and down. That is, when the Y-axis shown in FIG. 1 is moved forward and backward, a left-right axis (not shown, but a so-called X-axis) orthogonal to the Y-axis in a horizontal plane and a vertical Z-axis Has become possible.
[0023]
Further, a cradle movement (see arrow R) about the horizontal swing axis Q is also possible.
Thereby, when the extension shaft 22 is connected to the main spindle head 21 and the processing device 4 is provided at the lower end of the extension shaft 22, when the tire mold 100 is fixed on the surface plate 2, the tire mold 100 comes into contact with the tire mold 100. The processing device 4 can be moved in and out of the central space of the tire mold 100 without causing interference.
[0024]
A tool 25 such as an end mill can be attached to the front end of the processing device 4 in a laterally projecting state. The tool 25 is driven by a motor (not shown) incorporated in the processing apparatus 4 and is rotatable around a rotation axis along a laterally projecting direction.
As is clear from these descriptions, the tool 25 is provided in the molding space 101 of the tire mold 100 so as to protrude laterally toward the tread forming surface 102 formed over all the segments 103.
[0025]
The tool 25 allows the machine tool 20 to move the spindle head 21 along the X-axis, Y-axis, and Z-axis (including S-axis motion by a combination of Y-axis motion and Z-axis motion). In addition, as a comprehensive combination of being capable of cradle movement about the Q axis, a complex movement corresponding to the movement in the width direction of the tread molding surface 102 and the tread pattern (not shown) formed on the tread molding surface 102 Movements are possible.
In the tire mold manufacturing apparatus 1 having such a configuration, the tire mold 100 is fixed on the surface plate 2 by using the container 3, and then the portion of the machine tool 20 where the spindle head 21 is provided is moved to perform processing. The device 4 is inserted into the central space of the tire mold 100, and a motor (not shown) built in the processing device 4 is operated to rotate the tool 25.
[0026]
Then, the platen 2 is rotated while the tip of the tool 25 is pushed up to the tread forming surface 102 in the molding space 101 of the tire mold 100.
Further, the processing device 4 is moved up and down along the width of the tread forming surface 102 and the tread pattern while the processing of the tread forming surface 102 by the tool 25 is continued in this manner.
As a result, the tread forming surface 102 (formed by connecting all the segments 103) in the molding space 101 is continuously and continuously processed on the entire circumference by the tool 25 of the processing device 4.
[0027]
Therefore, the tread forming surface 102 of the tire mold 100 as a whole is finished with a high RRO (roundness).
If a tire is manufactured using the tire mold 100 manufactured in this manner, it goes without saying that the manufactured tire has a good radial force variation (RFV: variation in radial force).
FIG. 5 shows a second embodiment of the tire mold manufacturing apparatus 1 according to the present invention.
[0028]
The most different point of the tire mold manufacturing apparatus 1 of the second embodiment from the first embodiment is a structure for fixing the container 3 to the surface plate 2.
That is, in the second embodiment, the holding plate 17 is drawn to the container 3 by the pressing device 30 (a hydraulic or pneumatic cylinder or the like) connected to the platen 2, and the container 3 is moved to the platen 2. It is designed to be pressed.
It is preferable that a plurality of such pressing devices 30 be provided so as to surround the container 3 in a uniform arrangement, but a structure in which only one is provided and an engaging portion such as a hook is provided at another location may be provided.
[0029]
By the way, the present invention is not limited to the above embodiments, and can be appropriately changed according to the embodiments.
The processing device 4 may be configured such that a cutting tool is provided at an end thereof through an arm portion bent in an L-shape with respect to the spindle head 21 of the machine tool 20. That is, the machine tool 20 is used as a boring machine.
Instead of turning the surface plate 2 by the turntable 7, the processing device 4 may be turned.
[0030]
【The invention's effect】
As is apparent from the above description, the tire mold manufacturing method and manufacturing apparatus according to the present invention can manufacture a tire mold with an increased RRO or the like on the tread forming surface.
Therefore, if a tire is manufactured using this tire mold, the resulting tire can have a good RFV.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a first embodiment of a tire mold manufacturing apparatus according to the present invention.
FIG. 2 is a side view showing the processing apparatus employed in the first embodiment.
FIG. 3 is a perspective view of the processing apparatus shown in FIG. 2;
FIG. 4 is an exploded perspective view showing a container and the like for easy understanding.
FIG. 5 is a side sectional view showing a second embodiment of the tire mold manufacturing apparatus according to the present invention.
FIG. 6 is a perspective view showing a tire mold.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 tire mold manufacturing device 2 surface plate 3 container 4 processing device 7 turntable 17 holding plate 24 pull stud 25 tool 30 pressing device 100 tire mold 102 tread forming surface 103 segment

Claims (6)

In a method of manufacturing a tire mold (100) used at the time of vulcanizing a tire,
The segments (103) having a shape divided into a plurality in the circumferential direction are arranged in a circumferential arrangement on the surface plate (2) to assemble the tire mold (100), and the segments (103) are held by containers (3) arranged around the tire mold (100). A tire mold characterized by fixing the position of (103) and thereafter continuously processing and finishing a tread forming surface (102) formed over all the segments (103) in the tire mold (100) in a circumferential direction. Production method. For the tire mold (100) fixed on the surface plate (2), there is provided a processing device (4) for holding a tool (25) in a laterally projecting shape from a central space toward a tread forming surface (102). The tire according to claim 1, wherein the tread forming surface (102) is machine-finished by a tool (25) while relatively rotating the surface plate (2) and the machining device (4). Mold making method. A surface plate (2) capable of supporting a tire mold (100) used at the time of vulcanizing a tire, and a plurality of segments arranged on the surface plate (2) in a circumferential arrangement assuming the tire mold (100) ( A container (3) for holding 103) and a segment (103) fixed on the surface plate (2) corresponding to the tire mold (100) by being circumferentially connected inside the segments (103). A processing device (4) for continuously processing and finishing the tread forming surface (102) in the circumferential direction. A pressing plate (17) for positioning the segment (103) in the container (3) in a predetermined position by pressing the container (3) toward the surface plate (2) all around is provided. The tire mold manufacturing apparatus according to claim 3, wherein the board (17) can be bolted to the surface plate (2). A pressing plate (17) for positioning the segment (103) in the container (3) in a predetermined position by pressing the container (3) toward the surface plate (2) all around is provided. The tire mold manufacturing apparatus according to claim 3, further comprising a pressing device (30) capable of pressing the holding plate (17) toward the surface plate (2) by fluid pressure. The processing device (4) holds a tool (25) in a laterally projecting shape from a central space thereof toward a tread forming surface (102) with respect to a tire mold (100) fixed on a surface plate (2). And the tool (25) can be moved up and down in accordance with the width of the tread forming surface (102), and the platen (2) is provided on a turntable (7) for turning. The tire mold manufacturing apparatus according to any one of claims 3 to 5, wherein the apparatus is enabled.

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