JPS61195809A - Manufacture of mold for shaping tire - Google Patents

Abstract

PURPOSE:To contrive to reduce the time and the cost of manufacture of the title object by laser machining the side wall of ribs and/or lugs at the manufacture of a net ring. CONSTITUTION:At machining process, a net ring stock material 3' provided with a stationary part 15 is produced. The shaping of the side wall parts 6-1, 7-1, 8-1 of ribs 6, lugs 7, shoulder flames 8 and the shaping of a connecting member 14 are completed by laser machining. That is, e.g. the laser beam 16' emitted from a laser machining device capable of controlling five axes by NC method is made to pass along a specified route. Then, because the tem perature of the periphery of a closed loop is rapidly heightened, the machining position where unit hour machining is to be performed is kept away. Next, the machining of the top parts 6-2, 7-2, 8-2 of the ribs 6, the lug 7 and the shoulder frame 8 are achieved by electric discharge machining.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a mold for forming a tire, and particularly to a method for manufacturing a mold for a tire to be molded on a profile ring having a contour surface corresponding to the tread surface of the tire to be molded. In a method for manufacturing a tire molding die, in which a net ring made of ribs and/or lugs for forming a recess is placed, in manufacturing the net ring, the ribs and/or lugs are placed. The present invention also relates to a method for manufacturing a tire mold in which the manufacturing time is significantly reduced by laser processing the side wall portions of the lugs.

(Problems to be Solved by the Prior Art and the Invention) In general, tire molding molds, as shown in FIG.
The inner surface of the mold has a design corresponding to the outer shape of the tire to be molded, that is, a tread portion 1 corresponding to the tread of the tire and a rib portion 2 corresponding to the concave portion of the tire. It is well known that the design and dimensional accuracy formed by the bone portion 2 affect the tire's characteristics such as maneuverability, running performance, ground contact, and noise prevention.

Conventionally, the above-mentioned tire molding molds were made using plaster molding method,
The tread portion 1 and the bone portion 2 are integrally molded by a manufacturing method such as a sand casting method, a ceramic casting method, a mold casting method, other precision casting methods, an engraving method, or an electric discharge machining method, or It is installed in advance by welding the bone part 2 to the inner circumferential surface of the tread part 1. Therefore, every time the design of the tire is updated in order to improve the tire properties described above, it is necessary to renew the entire mold. Furthermore, it not only increases the cost of mold manufacturing, as it requires a huge amount of man-hours to rework and finish.
There were drawbacks such as a significantly longer manufacturing period.

In order to solve the above-mentioned drawbacks, the applicants of the present application have already made a series of proposals regarding a so-called net-ring type tire molding mold as shown in FIG. , patent application Sho 58-9530
No. 2).

FIG. 4(A) is a developed plan view of the mold surface in one embodiment of the tire molding mold proposed above, and FIG. 4(B) is
A) A sectional view taken along the arrow A--A; FIG. 4C shows a perspective view of the net ring. In the figure, 3 is a net ring, 3-1 is a joint surface, 4 is a profile ring, 4-1 is a contour surface, 4-2 is a profile ring outer peripheral surface, 5 is a holder, and 5-1 is a Holder inner peripheral surface, 6 is a rib, 6-1 is a rib side wall, 6-2 is a rib top, 7 is a lug, 7-1 is a lug side wall, 7-2 is a lug top, 8 is a shoulder bone (Although it corresponds to a lug in the present invention, it is called a shoulder bone portion to distinguish it from the lug 7.) 8-1 is a shoulder bone side wall portion, 8-
Reference numeral 2 represents the top of the shoulder bone, 9 represents a taper pin, 10 to 13 represent a bold, and 14 represents a connecting member.

The tire molding die illustrated in FIGS. 4(A) and 4(B) includes a profile ring 4 having a contour surface 4-1 corresponding to the outer shape including the tread of the tire to be molded;
a rib 6 having a joint surface 3-1 that contacts the contour surface 4-1 and forming a recess of the tire to be molded;
Net ring 3 with lugs 7, shoulder bones 8, etc.
It consists of That is, as shown in FIG. 4(B), the net ring 3 has a profile
A tapered bottle (a straight bottle may also be used) 9 or a bold bottle 10 is placed on the contour surface 4-1 of the ring 4. ,l
The profile ring 4 is further fixed to the profile ring 4 by the bold 12.1.
3 to be fixed to the holder 5.

In manufacturing the net ring 3, first, a net ring material is prepared which has a joint surface 3-1 that comes into contact with the contour surface 4-1 and has processing allowances for the ribs 6, lugs 7, etc. After manufacturing, the net ring material is processed using a processing means such as electrical discharge machining or laser machining, thereby manufacturing the net ring 3 as shown in FIG. 4(C).

Then, the net ring 3 has the above profile.
After performing predetermined positioning with respect to the ring 4, as described above, for example, taper bottle 9, bold bottle 10.1)
It is fixed by a fixing means such as. Note that the connecting member 14
is removed after the above positioning.

In the manufacturing process of the net ring 3 explained above, since the processing speed of the laser processing is high, the parts that can be processed by the laser processing include the ribs 6, the lugs 7, and the shoulder bones, which are straight parts in cross-section. The above-mentioned laser processing is used for processing each side wall portion 6-1.7-1.8-1 of 8. However, while laser machining has the advantage of being warmer and faster in machining speed than machining methods such as electric discharge machining, it is also processed at high temperatures, so the temperature effect on the workpiece is It becomes a problem.

In particular, if laser processing is performed locally and continuously for a long time on the ring-shaped net/ring material,
There is an undesirable problem in that a local temperature rise occurs and the roundness of the net ring material is deformed, making it impossible to perform highly accurate processing.

(Means for Solving the Problems) The present invention aims to solve the above-mentioned problems, and therefore, the method for manufacturing a tire molding mold of the present invention provides at least the tread surface of a tire to be molded. a profile ring having a contour surface corresponding to the profile ring; and a net ring comprising ribs and/or lugs having a joint surface that abuts the contour surface of the profile ring and forming the recess of the tire to be formed. In the method for manufacturing a tire molding die, the net ring is placed on the contour surface of the profile ring, the profile having a contour surface corresponding to the tread surface of the tire to be molded.・A profile ring production process for producing a ring, and a net ring consisting of ribs and/or lugs that have a joint surface that comes into contact with the contour surface of the profile ring and that is used to form the concave portion of the tire to be formed. It has a net ring manufacturing process that produces
A net ring material having a joint surface that comes into contact with the contour surface of the profile ring and a machining allowance for the ribs and/or lugs is manufactured, and the ribs and/or lugs to be processed on the net ring material are manufactured. After processing the side wall portion, which is a straight line portion in the cross-sectional shape of the lug, by laser processing, the rib to be processed and/or the top portion, which is a curved portion in the cross-sectional shape of the lug, is finished using an arbitrary finishing method. A net ring is manufactured by performing this process, and the net ring manufactured by the net ring manufacturing process is used as a profile ring manufactured by the above profile ring manufacturing process.
It is characterized by being manufactured so as to be placed on the contour surface of the ring. This will be explained below with reference to the drawings.

(Embodiments of the Invention) Fig. 1 (A) to F) is an explanatory diagram of an embodiment of the production process of a net ring in the present invention, and Fig. 2 is an embodiment of the production process of a profile ring in the present invention. An explanatory diagram, FIG. 3 is an explanatory diagram of an embodiment of the holder in the present invention,
FIGS. 4(A) to 4(C) show the construction of an embodiment of a tire molding mold manufactured according to the present invention.

In the figure, 3 is a net ring, 3-1 j171 joint surface, 3
' is the net ring material, 4 is the profile ring,
4-1 is a contour surface, 4-2 is an outer peripheral surface, 5 is a holder, 5
-1 is the inner peripheral surface, 6 is the rib, 7 is the lug, 8 is the shoulder bone, 6-1 to 8-1 is the side wall, 6-2 to 8-2 is the top of the head, 9 is the taper pin, 10 13 to 13 are bold, 9' to 13' are insertion holes, 12'' and 13'' are screw holes, 14 is a connecting member, 15 is a fixing part during processing, 16 is a laser processing device, 16' is a laser beam, 17 and 1
8 represents an electrode.

Figure 1 (A) shows the net ring manufacturing process in the present invention.
This will be explained in relation to or F). First, a net ring material 3' having a fixing part 15 during processing as shown in FIG. 1(A) is manufactured by machining. In addition, when producing the net ring material 3',
At least the joint surface 3-1 is processed with high precision using, for example, an NC lathe. Figure 1 (B
) is a sectional view taken along arrow B-B in FIG. 1(A).

Then, through laser machining and electrical discharge machining, which will be explained below,
Ribs 6 illustrated by dotted lines in FIG. 1(B),
The lug 7, shoulder bone portion 8 and connecting member 14 are molded.

As is generally well known, laser machining performs linear machining, and its machining speed is significantly higher than that of machining methods such as electrical discharge machining. By performing so-called 5-axis control, the ribs 6, lugs 7, shoulder bones 8 and other side wall portions 6-1, ? -1, 8-1, etc. processing can be performed. Therefore, in the present invention, as shown in FIG. Molding is done by laser processing. That is,
For example, a laser processing device 1 capable of 5-axis control using NC control
The above laser processing is performed by causing the laser beam 16' output from 6 to run along a predetermined route. Note that in FIG. 1(C), only the side wall portion 6-1.8-1 is shown due to the cross-sectional position.
It goes without saying that the other side wall portions 7-1 and connecting members 14 can be processed in the same manner.

As explained at the beginning of this specification, when the laser processing is performed locally for a long time, the net ring material 3' deforms due to the local temperature rise. occurs, which hinders high-precision machining.

Therefore, in the present invention, for example, as shown in FIG.
The machining positions are dispersed according to the machining order indicated by [phase]. That is, if, for example, the closed loop machining of ■, O20, and @ shown in FIG.
As mentioned above, the temperature around the closed loop increases rapidly, which is not preferable. Note that FIG. 1(D) is for explaining that the laser processing in the present invention is performed by sequentially distributing the positions, and the present invention is not limited to this. Limiting continuous unit time machining within a predetermined machining time,
The machining positions at which the respective unit time machining operations are performed may be performed so as not to be close to each other.

Next, the rib 6, the lug 7, and the top portion 6-2 of the shoulder bone portion 8 are processed by electric discharge machining (as shown in FIGS. 1(E) and 1(F)).
7-2. Perform the processing in 8-2. The electrical discharge machining may basically be carried out as already proposed by the applicants of the present application (eg, Japanese Patent Application No. 58-33994). Therefore, although a detailed explanation will be omitted, for example, as shown in FIGS. 1(E) and (F), the portion shown by the arrow C is formed by electrical discharge machining in which the electrode 17 is fed in the direction of the arrow X. , and the portion indicated by the arrow in the figure is formed by electric discharge machining in which the electrode 18 is fed in the composite direction XZ of the arrow X direction and the Z direction in the figure. In this way, the net ring 3 as shown in the perspective view of FIG. 4(C) is completed. The net ring 3 was cut off at the position indicated by the arrow [F] in FIG. 1(F) after the electrical discharge machining described above, and the fixing portion 15 was removed during machining. In addition, the rib 6,
Lug 7, top of shoulder bone 8 6-2.7-2.8-
Although it has been explained that the machining in step 2 is performed by electric discharge machining, it goes without saying that other machining means such as manual machining may be used.

Next, the manufacturing process of the profile ring 4 will be explained. In the manufacturing process, as shown in FIG. 2, a contour surface 4-1 corresponding to the tread surface of the tire to be molded, that is, the bonding surface 3-1 of the net ring 3, and a fixing surface for the holder 5, which will be described later, are formed. The outer circumferential surface 4-2 is provided with an outer circumferential surface 4-2, as well as bold insertion holes 10' and 1)' for inserting the bold 10.1) for fixing the net ring 3, and for setting the taper pin 9. It is manufactured to have a taper pin insertion hole 9', a bold insertion hole 12' for inserting a ball (12) for fixing the profile ring 4 to the holder 5, a screw hole 13'' for setting the bold 13, etc. Ru.

Furthermore, a holder 5 for fixing the profile ring 4 is manufactured as shown in FIG. That is, the inner peripheral surface 5-1 of the holder 5 is the same as the outer peripheral surface 4 of the profile ring 4.
-2. The holder 5 has a screw hole 12'' of the bold 12 for fixing the profile ring 4, and a bold insertion hole 13' for inserting the bold 13.

By combining the net ring 3, profile ring 4, and holder 5 manufactured based on the manufacturing processes described above as shown in FIGS. 4(A) and 4(B) at the beginning of this specification, The tire molding mold of the invention is completed. The order of assembly is such that the net ring 3 and profile ring 4 are first assembled and fixed, and then the profile ring 4 is fixed to the holder 5.

Furthermore, in the tire molding mold manufactured by the manufacturing method of the present invention, when removing the profile ring 4 and the net ring 3 from the holder 5, for example when updating the tire design, All you have to do is reverse the assembly procedure above.

As explained above, in the present invention, the net ring 3, the profile ring 4, and the holder 5 are individually manufactured as in the embodiment shown in FIGS.
A ring 3 and a profile ring 4 are placed on a holder 5. Then, when updating the tire design, for example, only the net ring 3 and/or profile ring 4 can be replaced while leaving the holder 5 as is. Also, net ring 3
In the manufacturing process, laser machining is limited to a predetermined time and is repeated at different positions, thereby preventing the effects of temperature rise and achieving high speed and high accuracy. be able to.

In addition, in the above explanation, "net ring" and "
Although the word "ring" was used, the above "ring" is
Needless to say, it includes a ring-shaped structure formed by connecting arc-shaped bodies.

Further, in the description of the present invention, it has been explained that the net ring 3, profile ring 4, and holder 5 are manufactured individually, but the profile ring 4 and the holder 5 may also be manufactured integrally. good.

(Effects of the Invention) As explained above, according to the present invention, it is possible to prevent temperature effects during laser processing, so that nets and rings that require high precision can be processed at high speed by laser processing. I can do it. Therefore, it is possible to provide a method for manufacturing a tire mold that greatly contributes to a significant reduction in manufacturing time and manufacturing cost.

[Brief explanation of drawings]

1(A) to F) are explanatory diagrams of one embodiment of the manufacturing process of a net ring according to the present invention, FIGS. The figure is an explanatory diagram of an embodiment of the holder according to the present invention.
FIGS. 4(A) to 4(C) are block diagrams of one embodiment of a tire molding mold manufactured according to the present invention, and FIG. 5 is a sectional view showing a general example of a tire molding mold. In the figure, 3 is a net ring, 3' is a net ring material, 3-1 is a joint surface, 4 is a profile ring, 4
-1 is the contour surface, 5 is the holder, 6 is the rib, 7 is the lug,
8 is the shoulder bone part, 6-1 to 8-1 are the side wall parts, 6-
2 to 8-2 are the top of the head, 9 is a taper pin, IO to 13 are bold, 14 is a connecting member, 15 is a fixing part during processing, 16 is a laser processing device, 16' is a laser beam,
17 and 18 represent electrodes.

Claims (4)

[Claims] (1) A profile ring having at least a contour surface corresponding to the tread surface of the tire to be molded, and a joint surface that abuts the contour surface of the profile ring, and for molding the recess of the tire to be molded. A method for manufacturing a tire molding die comprising a net ring consisting of ribs and/or lugs, the net ring being placed on the contour surface of the profile ring, wherein the tire to be molded is a profile ring manufacturing process for manufacturing a profile ring having a contour surface corresponding to the tread surface of the profile ring; It has a net ring manufacturing process of manufacturing a net ring consisting of ribs and/or lugs, and in the net ring manufacturing process,
A net ring material having a joint surface that comes into contact with the contour surface of the profile ring and a machining allowance for the ribs and/or lugs is manufactured, and the ribs and/or lugs to be processed on the net ring material are manufactured. After processing the side wall portion, which is a straight line portion in the cross-sectional shape of the lug, by laser processing, the rib to be processed and/or the top portion, which is a curved portion in the cross-sectional shape of the lug, is finished using an arbitrary finishing method. A net ring is manufactured by performing this process, and the net ring manufactured by the net ring manufacturing process is used as a profile ring manufactured by the above profile ring manufacturing process.
1. A method for manufacturing a tire molding die, characterized in that the mold is manufactured by being placed on the contour surface of a ring. (2) The laser processing in the net ring manufacturing process is performed by irradiating a laser beam from the joint surface side of the net ring material. A method for manufacturing a tire mold. (3) The laser processing in the net ring manufacturing process is performed repeatedly in a unit time limited to a predetermined time. 2) The method for manufacturing a tire molding mold as described in item 2). (4) Manufacture of a tire molding mold according to claim (1), wherein the finishing of the top of the rib and/or lug in the net ring manufacturing process is performed by electrical discharge machining. Method.